5831 lines
141 KiB
C
5831 lines
141 KiB
C
/*
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* NSA Security-Enhanced Linux (SELinux) security module
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*
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* This file contains the SELinux hook function implementations.
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*
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* Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
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* Chris Vance, <cvance@nai.com>
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* Wayne Salamon, <wsalamon@nai.com>
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* James Morris <jmorris@redhat.com>
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*
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* Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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* Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
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* Eric Paris <eparis@redhat.com>
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* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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* <dgoeddel@trustedcs.com>
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* Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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* Paul Moore <paul.moore@hp.com>
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* Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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* Yuichi Nakamura <ynakam@hitachisoft.jp>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2,
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* as published by the Free Software Foundation.
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*/
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#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
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#include <linux/ext2_fs.h>
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#include <linux/sched.h>
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#include <linux/security.h>
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#include <linux/xattr.h>
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#include <linux/capability.h>
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#include <linux/unistd.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/slab.h>
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#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
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#include <linux/spinlock.h>
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#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
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#include <linux/mount.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/netfilter_ipv6.h>
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#include <linux/tty.h>
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#include <net/icmp.h>
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#include <net/ip.h> /* for local_port_range[] */
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#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <asm/atomic.h>
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#include <linux/bitops.h>
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#include <linux/interrupt.h>
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#include <linux/netdevice.h> /* for network interface checks */
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#include <linux/netlink.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
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#include <linux/un.h> /* for Unix socket types */
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#include <net/af_unix.h> /* for Unix socket types */
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#include <linux/parser.h>
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#include <linux/nfs_mount.h>
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#include <net/ipv6.h>
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#include <linux/hugetlb.h>
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#include <linux/personality.h>
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#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include "avc.h"
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#include "objsec.h"
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#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#define NUM_SEL_MNT_OPTS 5
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extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
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{
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unsigned long enforcing;
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if (!strict_strtoul(str, 0, &enforcing))
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selinux_enforcing = enforcing ? 1 : 0;
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return 1;
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}
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__setup("enforcing=", enforcing_setup);
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#endif
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#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
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int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
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static int __init selinux_enabled_setup(char *str)
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{
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unsigned long enabled;
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if (!strict_strtoul(str, 0, &enabled))
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selinux_enabled = enabled ? 1 : 0;
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return 1;
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}
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__setup("selinux=", selinux_enabled_setup);
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#else
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int selinux_enabled = 1;
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#endif
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static struct kmem_cache *sel_inode_cache;
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/**
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* selinux_secmark_enabled - Check to see if SECMARK is currently enabled
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*
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* Description:
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* This function checks the SECMARK reference counter to see if any SECMARK
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* targets are currently configured, if the reference counter is greater than
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* zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
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* enabled, false (0) if SECMARK is disabled.
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*
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*/
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static int selinux_secmark_enabled(void)
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{
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return (atomic_read(&selinux_secmark_refcount) > 0);
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}
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/*
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* initialise the security for the init task
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*/
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static void cred_init_security(void)
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{
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struct cred *cred = (struct cred *) current->real_cred;
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struct task_security_struct *tsec;
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tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
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if (!tsec)
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panic("SELinux: Failed to initialize initial task.\n");
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tsec->osid = tsec->sid = SECINITSID_KERNEL;
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cred->security = tsec;
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}
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/*
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* get the security ID of a set of credentials
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*/
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static inline u32 cred_sid(const struct cred *cred)
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{
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const struct task_security_struct *tsec;
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tsec = cred->security;
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return tsec->sid;
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}
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/*
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* get the objective security ID of a task
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*/
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static inline u32 task_sid(const struct task_struct *task)
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{
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u32 sid;
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rcu_read_lock();
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sid = cred_sid(__task_cred(task));
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rcu_read_unlock();
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return sid;
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}
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/*
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* get the subjective security ID of the current task
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*/
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static inline u32 current_sid(void)
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{
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const struct task_security_struct *tsec = current_security();
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return tsec->sid;
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}
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/* Allocate and free functions for each kind of security blob. */
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static int inode_alloc_security(struct inode *inode)
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{
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struct inode_security_struct *isec;
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u32 sid = current_sid();
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isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
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if (!isec)
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return -ENOMEM;
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mutex_init(&isec->lock);
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INIT_LIST_HEAD(&isec->list);
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isec->inode = inode;
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isec->sid = SECINITSID_UNLABELED;
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isec->sclass = SECCLASS_FILE;
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isec->task_sid = sid;
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inode->i_security = isec;
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return 0;
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}
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static void inode_free_security(struct inode *inode)
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{
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struct inode_security_struct *isec = inode->i_security;
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struct superblock_security_struct *sbsec = inode->i_sb->s_security;
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spin_lock(&sbsec->isec_lock);
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if (!list_empty(&isec->list))
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list_del_init(&isec->list);
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spin_unlock(&sbsec->isec_lock);
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inode->i_security = NULL;
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kmem_cache_free(sel_inode_cache, isec);
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}
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static int file_alloc_security(struct file *file)
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{
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struct file_security_struct *fsec;
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u32 sid = current_sid();
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fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
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if (!fsec)
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return -ENOMEM;
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fsec->sid = sid;
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fsec->fown_sid = sid;
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file->f_security = fsec;
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return 0;
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}
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static void file_free_security(struct file *file)
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{
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struct file_security_struct *fsec = file->f_security;
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file->f_security = NULL;
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kfree(fsec);
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}
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static int superblock_alloc_security(struct super_block *sb)
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{
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struct superblock_security_struct *sbsec;
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sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
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if (!sbsec)
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return -ENOMEM;
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mutex_init(&sbsec->lock);
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INIT_LIST_HEAD(&sbsec->isec_head);
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spin_lock_init(&sbsec->isec_lock);
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sbsec->sb = sb;
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sbsec->sid = SECINITSID_UNLABELED;
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sbsec->def_sid = SECINITSID_FILE;
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sbsec->mntpoint_sid = SECINITSID_UNLABELED;
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sb->s_security = sbsec;
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return 0;
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}
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static void superblock_free_security(struct super_block *sb)
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{
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struct superblock_security_struct *sbsec = sb->s_security;
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sb->s_security = NULL;
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kfree(sbsec);
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}
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/* The security server must be initialized before
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any labeling or access decisions can be provided. */
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extern int ss_initialized;
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/* The file system's label must be initialized prior to use. */
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static const char *labeling_behaviors[6] = {
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"uses xattr",
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"uses transition SIDs",
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"uses task SIDs",
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"uses genfs_contexts",
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"not configured for labeling",
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"uses mountpoint labeling",
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};
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static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
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static inline int inode_doinit(struct inode *inode)
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{
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return inode_doinit_with_dentry(inode, NULL);
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}
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enum {
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Opt_error = -1,
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Opt_context = 1,
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Opt_fscontext = 2,
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Opt_defcontext = 3,
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Opt_rootcontext = 4,
|
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Opt_labelsupport = 5,
|
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};
|
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|
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static const match_table_t tokens = {
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{Opt_context, CONTEXT_STR "%s"},
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{Opt_fscontext, FSCONTEXT_STR "%s"},
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{Opt_defcontext, DEFCONTEXT_STR "%s"},
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{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
|
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{Opt_labelsupport, LABELSUPP_STR},
|
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{Opt_error, NULL},
|
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};
|
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|
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#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
|
|
|
|
static int may_context_mount_sb_relabel(u32 sid,
|
|
struct superblock_security_struct *sbsec,
|
|
const struct cred *cred)
|
|
{
|
|
const struct task_security_struct *tsec = cred->security;
|
|
int rc;
|
|
|
|
rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
|
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FILESYSTEM__RELABELFROM, NULL);
|
|
if (rc)
|
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return rc;
|
|
|
|
rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__RELABELTO, NULL);
|
|
return rc;
|
|
}
|
|
|
|
static int may_context_mount_inode_relabel(u32 sid,
|
|
struct superblock_security_struct *sbsec,
|
|
const struct cred *cred)
|
|
{
|
|
const struct task_security_struct *tsec = cred->security;
|
|
int rc;
|
|
rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__RELABELFROM, NULL);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__ASSOCIATE, NULL);
|
|
return rc;
|
|
}
|
|
|
|
static int sb_finish_set_opts(struct super_block *sb)
|
|
{
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
struct dentry *root = sb->s_root;
|
|
struct inode *root_inode = root->d_inode;
|
|
int rc = 0;
|
|
|
|
if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
|
|
/* Make sure that the xattr handler exists and that no
|
|
error other than -ENODATA is returned by getxattr on
|
|
the root directory. -ENODATA is ok, as this may be
|
|
the first boot of the SELinux kernel before we have
|
|
assigned xattr values to the filesystem. */
|
|
if (!root_inode->i_op->getxattr) {
|
|
printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
|
|
"xattr support\n", sb->s_id, sb->s_type->name);
|
|
rc = -EOPNOTSUPP;
|
|
goto out;
|
|
}
|
|
rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
|
|
if (rc < 0 && rc != -ENODATA) {
|
|
if (rc == -EOPNOTSUPP)
|
|
printk(KERN_WARNING "SELinux: (dev %s, type "
|
|
"%s) has no security xattr handler\n",
|
|
sb->s_id, sb->s_type->name);
|
|
else
|
|
printk(KERN_WARNING "SELinux: (dev %s, type "
|
|
"%s) getxattr errno %d\n", sb->s_id,
|
|
sb->s_type->name, -rc);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
|
|
|
|
if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
|
|
printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
|
|
sb->s_id, sb->s_type->name);
|
|
else
|
|
printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
|
|
sb->s_id, sb->s_type->name,
|
|
labeling_behaviors[sbsec->behavior-1]);
|
|
|
|
if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
|
|
sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
|
|
sbsec->behavior == SECURITY_FS_USE_NONE ||
|
|
sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
|
|
sbsec->flags &= ~SE_SBLABELSUPP;
|
|
|
|
/* Special handling for sysfs. Is genfs but also has setxattr handler*/
|
|
if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
|
|
sbsec->flags |= SE_SBLABELSUPP;
|
|
|
|
/* Initialize the root inode. */
|
|
rc = inode_doinit_with_dentry(root_inode, root);
|
|
|
|
/* Initialize any other inodes associated with the superblock, e.g.
|
|
inodes created prior to initial policy load or inodes created
|
|
during get_sb by a pseudo filesystem that directly
|
|
populates itself. */
|
|
spin_lock(&sbsec->isec_lock);
|
|
next_inode:
|
|
if (!list_empty(&sbsec->isec_head)) {
|
|
struct inode_security_struct *isec =
|
|
list_entry(sbsec->isec_head.next,
|
|
struct inode_security_struct, list);
|
|
struct inode *inode = isec->inode;
|
|
spin_unlock(&sbsec->isec_lock);
|
|
inode = igrab(inode);
|
|
if (inode) {
|
|
if (!IS_PRIVATE(inode))
|
|
inode_doinit(inode);
|
|
iput(inode);
|
|
}
|
|
spin_lock(&sbsec->isec_lock);
|
|
list_del_init(&isec->list);
|
|
goto next_inode;
|
|
}
|
|
spin_unlock(&sbsec->isec_lock);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* This function should allow an FS to ask what it's mount security
|
|
* options were so it can use those later for submounts, displaying
|
|
* mount options, or whatever.
|
|
*/
|
|
static int selinux_get_mnt_opts(const struct super_block *sb,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
int rc = 0, i;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
char *context = NULL;
|
|
u32 len;
|
|
char tmp;
|
|
|
|
security_init_mnt_opts(opts);
|
|
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
return -EINVAL;
|
|
|
|
if (!ss_initialized)
|
|
return -EINVAL;
|
|
|
|
tmp = sbsec->flags & SE_MNTMASK;
|
|
/* count the number of mount options for this sb */
|
|
for (i = 0; i < 8; i++) {
|
|
if (tmp & 0x01)
|
|
opts->num_mnt_opts++;
|
|
tmp >>= 1;
|
|
}
|
|
/* Check if the Label support flag is set */
|
|
if (sbsec->flags & SE_SBLABELSUPP)
|
|
opts->num_mnt_opts++;
|
|
|
|
opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
|
|
if (!opts->mnt_opts) {
|
|
rc = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
|
|
opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
|
|
if (!opts->mnt_opts_flags) {
|
|
rc = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
|
|
i = 0;
|
|
if (sbsec->flags & FSCONTEXT_MNT) {
|
|
rc = security_sid_to_context(sbsec->sid, &context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & CONTEXT_MNT) {
|
|
rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = CONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & DEFCONTEXT_MNT) {
|
|
rc = security_sid_to_context(sbsec->def_sid, &context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & ROOTCONTEXT_MNT) {
|
|
struct inode *root = sbsec->sb->s_root->d_inode;
|
|
struct inode_security_struct *isec = root->i_security;
|
|
|
|
rc = security_sid_to_context(isec->sid, &context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & SE_SBLABELSUPP) {
|
|
opts->mnt_opts[i] = NULL;
|
|
opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
|
|
}
|
|
|
|
BUG_ON(i != opts->num_mnt_opts);
|
|
|
|
return 0;
|
|
|
|
out_free:
|
|
security_free_mnt_opts(opts);
|
|
return rc;
|
|
}
|
|
|
|
static int bad_option(struct superblock_security_struct *sbsec, char flag,
|
|
u32 old_sid, u32 new_sid)
|
|
{
|
|
char mnt_flags = sbsec->flags & SE_MNTMASK;
|
|
|
|
/* check if the old mount command had the same options */
|
|
if (sbsec->flags & SE_SBINITIALIZED)
|
|
if (!(sbsec->flags & flag) ||
|
|
(old_sid != new_sid))
|
|
return 1;
|
|
|
|
/* check if we were passed the same options twice,
|
|
* aka someone passed context=a,context=b
|
|
*/
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
if (mnt_flags & flag)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allow filesystems with binary mount data to explicitly set mount point
|
|
* labeling information.
|
|
*/
|
|
static int selinux_set_mnt_opts(struct super_block *sb,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int rc = 0, i;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
const char *name = sb->s_type->name;
|
|
struct inode *inode = sbsec->sb->s_root->d_inode;
|
|
struct inode_security_struct *root_isec = inode->i_security;
|
|
u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
|
|
u32 defcontext_sid = 0;
|
|
char **mount_options = opts->mnt_opts;
|
|
int *flags = opts->mnt_opts_flags;
|
|
int num_opts = opts->num_mnt_opts;
|
|
|
|
mutex_lock(&sbsec->lock);
|
|
|
|
if (!ss_initialized) {
|
|
if (!num_opts) {
|
|
/* Defer initialization until selinux_complete_init,
|
|
after the initial policy is loaded and the security
|
|
server is ready to handle calls. */
|
|
goto out;
|
|
}
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING "SELinux: Unable to set superblock options "
|
|
"before the security server is initialized\n");
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Binary mount data FS will come through this function twice. Once
|
|
* from an explicit call and once from the generic calls from the vfs.
|
|
* Since the generic VFS calls will not contain any security mount data
|
|
* we need to skip the double mount verification.
|
|
*
|
|
* This does open a hole in which we will not notice if the first
|
|
* mount using this sb set explict options and a second mount using
|
|
* this sb does not set any security options. (The first options
|
|
* will be used for both mounts)
|
|
*/
|
|
if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
|
|
&& (num_opts == 0))
|
|
goto out;
|
|
|
|
/*
|
|
* parse the mount options, check if they are valid sids.
|
|
* also check if someone is trying to mount the same sb more
|
|
* than once with different security options.
|
|
*/
|
|
for (i = 0; i < num_opts; i++) {
|
|
u32 sid;
|
|
|
|
if (flags[i] == SE_SBLABELSUPP)
|
|
continue;
|
|
rc = security_context_to_sid(mount_options[i],
|
|
strlen(mount_options[i]), &sid);
|
|
if (rc) {
|
|
printk(KERN_WARNING "SELinux: security_context_to_sid"
|
|
"(%s) failed for (dev %s, type %s) errno=%d\n",
|
|
mount_options[i], sb->s_id, name, rc);
|
|
goto out;
|
|
}
|
|
switch (flags[i]) {
|
|
case FSCONTEXT_MNT:
|
|
fscontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
|
|
fscontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= FSCONTEXT_MNT;
|
|
break;
|
|
case CONTEXT_MNT:
|
|
context_sid = sid;
|
|
|
|
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
|
|
context_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= CONTEXT_MNT;
|
|
break;
|
|
case ROOTCONTEXT_MNT:
|
|
rootcontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
|
|
rootcontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= ROOTCONTEXT_MNT;
|
|
|
|
break;
|
|
case DEFCONTEXT_MNT:
|
|
defcontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
|
|
defcontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= DEFCONTEXT_MNT;
|
|
|
|
break;
|
|
default:
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (sbsec->flags & SE_SBINITIALIZED) {
|
|
/* previously mounted with options, but not on this attempt? */
|
|
if ((sbsec->flags & SE_MNTMASK) && !num_opts)
|
|
goto out_double_mount;
|
|
rc = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (strcmp(sb->s_type->name, "proc") == 0)
|
|
sbsec->flags |= SE_SBPROC;
|
|
|
|
/* Determine the labeling behavior to use for this filesystem type. */
|
|
rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
|
|
if (rc) {
|
|
printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
|
|
__func__, sb->s_type->name, rc);
|
|
goto out;
|
|
}
|
|
|
|
/* sets the context of the superblock for the fs being mounted. */
|
|
if (fscontext_sid) {
|
|
rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
|
|
if (rc)
|
|
goto out;
|
|
|
|
sbsec->sid = fscontext_sid;
|
|
}
|
|
|
|
/*
|
|
* Switch to using mount point labeling behavior.
|
|
* sets the label used on all file below the mountpoint, and will set
|
|
* the superblock context if not already set.
|
|
*/
|
|
if (context_sid) {
|
|
if (!fscontext_sid) {
|
|
rc = may_context_mount_sb_relabel(context_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
sbsec->sid = context_sid;
|
|
} else {
|
|
rc = may_context_mount_inode_relabel(context_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
if (!rootcontext_sid)
|
|
rootcontext_sid = context_sid;
|
|
|
|
sbsec->mntpoint_sid = context_sid;
|
|
sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
|
|
}
|
|
|
|
if (rootcontext_sid) {
|
|
rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
|
|
root_isec->sid = rootcontext_sid;
|
|
root_isec->initialized = 1;
|
|
}
|
|
|
|
if (defcontext_sid) {
|
|
if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING "SELinux: defcontext option is "
|
|
"invalid for this filesystem type\n");
|
|
goto out;
|
|
}
|
|
|
|
if (defcontext_sid != sbsec->def_sid) {
|
|
rc = may_context_mount_inode_relabel(defcontext_sid,
|
|
sbsec, cred);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
sbsec->def_sid = defcontext_sid;
|
|
}
|
|
|
|
rc = sb_finish_set_opts(sb);
|
|
out:
|
|
mutex_unlock(&sbsec->lock);
|
|
return rc;
|
|
out_double_mount:
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
|
|
"security settings for (dev %s, type %s)\n", sb->s_id, name);
|
|
goto out;
|
|
}
|
|
|
|
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
|
|
struct super_block *newsb)
|
|
{
|
|
const struct superblock_security_struct *oldsbsec = oldsb->s_security;
|
|
struct superblock_security_struct *newsbsec = newsb->s_security;
|
|
|
|
int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
|
|
int set_context = (oldsbsec->flags & CONTEXT_MNT);
|
|
int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
|
|
|
|
/*
|
|
* if the parent was able to be mounted it clearly had no special lsm
|
|
* mount options. thus we can safely deal with this superblock later
|
|
*/
|
|
if (!ss_initialized)
|
|
return;
|
|
|
|
/* how can we clone if the old one wasn't set up?? */
|
|
BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
|
|
|
|
/* if fs is reusing a sb, just let its options stand... */
|
|
if (newsbsec->flags & SE_SBINITIALIZED)
|
|
return;
|
|
|
|
mutex_lock(&newsbsec->lock);
|
|
|
|
newsbsec->flags = oldsbsec->flags;
|
|
|
|
newsbsec->sid = oldsbsec->sid;
|
|
newsbsec->def_sid = oldsbsec->def_sid;
|
|
newsbsec->behavior = oldsbsec->behavior;
|
|
|
|
if (set_context) {
|
|
u32 sid = oldsbsec->mntpoint_sid;
|
|
|
|
if (!set_fscontext)
|
|
newsbsec->sid = sid;
|
|
if (!set_rootcontext) {
|
|
struct inode *newinode = newsb->s_root->d_inode;
|
|
struct inode_security_struct *newisec = newinode->i_security;
|
|
newisec->sid = sid;
|
|
}
|
|
newsbsec->mntpoint_sid = sid;
|
|
}
|
|
if (set_rootcontext) {
|
|
const struct inode *oldinode = oldsb->s_root->d_inode;
|
|
const struct inode_security_struct *oldisec = oldinode->i_security;
|
|
struct inode *newinode = newsb->s_root->d_inode;
|
|
struct inode_security_struct *newisec = newinode->i_security;
|
|
|
|
newisec->sid = oldisec->sid;
|
|
}
|
|
|
|
sb_finish_set_opts(newsb);
|
|
mutex_unlock(&newsbsec->lock);
|
|
}
|
|
|
|
static int selinux_parse_opts_str(char *options,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
char *p;
|
|
char *context = NULL, *defcontext = NULL;
|
|
char *fscontext = NULL, *rootcontext = NULL;
|
|
int rc, num_mnt_opts = 0;
|
|
|
|
opts->num_mnt_opts = 0;
|
|
|
|
/* Standard string-based options. */
|
|
while ((p = strsep(&options, "|")) != NULL) {
|
|
int token;
|
|
substring_t args[MAX_OPT_ARGS];
|
|
|
|
if (!*p)
|
|
continue;
|
|
|
|
token = match_token(p, tokens, args);
|
|
|
|
switch (token) {
|
|
case Opt_context:
|
|
if (context || defcontext) {
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
context = match_strdup(&args[0]);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_fscontext:
|
|
if (fscontext) {
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
fscontext = match_strdup(&args[0]);
|
|
if (!fscontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_rootcontext:
|
|
if (rootcontext) {
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
rootcontext = match_strdup(&args[0]);
|
|
if (!rootcontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_defcontext:
|
|
if (context || defcontext) {
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
defcontext = match_strdup(&args[0]);
|
|
if (!defcontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
case Opt_labelsupport:
|
|
break;
|
|
default:
|
|
rc = -EINVAL;
|
|
printk(KERN_WARNING "SELinux: unknown mount option\n");
|
|
goto out_err;
|
|
|
|
}
|
|
}
|
|
|
|
rc = -ENOMEM;
|
|
opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
|
|
if (!opts->mnt_opts)
|
|
goto out_err;
|
|
|
|
opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
|
|
if (!opts->mnt_opts_flags) {
|
|
kfree(opts->mnt_opts);
|
|
goto out_err;
|
|
}
|
|
|
|
if (fscontext) {
|
|
opts->mnt_opts[num_mnt_opts] = fscontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
|
|
}
|
|
if (context) {
|
|
opts->mnt_opts[num_mnt_opts] = context;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
|
|
}
|
|
if (rootcontext) {
|
|
opts->mnt_opts[num_mnt_opts] = rootcontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
|
|
}
|
|
if (defcontext) {
|
|
opts->mnt_opts[num_mnt_opts] = defcontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
|
|
}
|
|
|
|
opts->num_mnt_opts = num_mnt_opts;
|
|
return 0;
|
|
|
|
out_err:
|
|
kfree(context);
|
|
kfree(defcontext);
|
|
kfree(fscontext);
|
|
kfree(rootcontext);
|
|
return rc;
|
|
}
|
|
/*
|
|
* string mount options parsing and call set the sbsec
|
|
*/
|
|
static int superblock_doinit(struct super_block *sb, void *data)
|
|
{
|
|
int rc = 0;
|
|
char *options = data;
|
|
struct security_mnt_opts opts;
|
|
|
|
security_init_mnt_opts(&opts);
|
|
|
|
if (!data)
|
|
goto out;
|
|
|
|
BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
|
|
|
|
rc = selinux_parse_opts_str(options, &opts);
|
|
if (rc)
|
|
goto out_err;
|
|
|
|
out:
|
|
rc = selinux_set_mnt_opts(sb, &opts);
|
|
|
|
out_err:
|
|
security_free_mnt_opts(&opts);
|
|
return rc;
|
|
}
|
|
|
|
static void selinux_write_opts(struct seq_file *m,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
int i;
|
|
char *prefix;
|
|
|
|
for (i = 0; i < opts->num_mnt_opts; i++) {
|
|
char *has_comma;
|
|
|
|
if (opts->mnt_opts[i])
|
|
has_comma = strchr(opts->mnt_opts[i], ',');
|
|
else
|
|
has_comma = NULL;
|
|
|
|
switch (opts->mnt_opts_flags[i]) {
|
|
case CONTEXT_MNT:
|
|
prefix = CONTEXT_STR;
|
|
break;
|
|
case FSCONTEXT_MNT:
|
|
prefix = FSCONTEXT_STR;
|
|
break;
|
|
case ROOTCONTEXT_MNT:
|
|
prefix = ROOTCONTEXT_STR;
|
|
break;
|
|
case DEFCONTEXT_MNT:
|
|
prefix = DEFCONTEXT_STR;
|
|
break;
|
|
case SE_SBLABELSUPP:
|
|
seq_putc(m, ',');
|
|
seq_puts(m, LABELSUPP_STR);
|
|
continue;
|
|
default:
|
|
BUG();
|
|
return;
|
|
};
|
|
/* we need a comma before each option */
|
|
seq_putc(m, ',');
|
|
seq_puts(m, prefix);
|
|
if (has_comma)
|
|
seq_putc(m, '\"');
|
|
seq_puts(m, opts->mnt_opts[i]);
|
|
if (has_comma)
|
|
seq_putc(m, '\"');
|
|
}
|
|
}
|
|
|
|
static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
|
|
{
|
|
struct security_mnt_opts opts;
|
|
int rc;
|
|
|
|
rc = selinux_get_mnt_opts(sb, &opts);
|
|
if (rc) {
|
|
/* before policy load we may get EINVAL, don't show anything */
|
|
if (rc == -EINVAL)
|
|
rc = 0;
|
|
return rc;
|
|
}
|
|
|
|
selinux_write_opts(m, &opts);
|
|
|
|
security_free_mnt_opts(&opts);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static inline u16 inode_mode_to_security_class(umode_t mode)
|
|
{
|
|
switch (mode & S_IFMT) {
|
|
case S_IFSOCK:
|
|
return SECCLASS_SOCK_FILE;
|
|
case S_IFLNK:
|
|
return SECCLASS_LNK_FILE;
|
|
case S_IFREG:
|
|
return SECCLASS_FILE;
|
|
case S_IFBLK:
|
|
return SECCLASS_BLK_FILE;
|
|
case S_IFDIR:
|
|
return SECCLASS_DIR;
|
|
case S_IFCHR:
|
|
return SECCLASS_CHR_FILE;
|
|
case S_IFIFO:
|
|
return SECCLASS_FIFO_FILE;
|
|
|
|
}
|
|
|
|
return SECCLASS_FILE;
|
|
}
|
|
|
|
static inline int default_protocol_stream(int protocol)
|
|
{
|
|
return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
|
|
}
|
|
|
|
static inline int default_protocol_dgram(int protocol)
|
|
{
|
|
return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
|
|
}
|
|
|
|
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
|
|
{
|
|
switch (family) {
|
|
case PF_UNIX:
|
|
switch (type) {
|
|
case SOCK_STREAM:
|
|
case SOCK_SEQPACKET:
|
|
return SECCLASS_UNIX_STREAM_SOCKET;
|
|
case SOCK_DGRAM:
|
|
return SECCLASS_UNIX_DGRAM_SOCKET;
|
|
}
|
|
break;
|
|
case PF_INET:
|
|
case PF_INET6:
|
|
switch (type) {
|
|
case SOCK_STREAM:
|
|
if (default_protocol_stream(protocol))
|
|
return SECCLASS_TCP_SOCKET;
|
|
else
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
case SOCK_DGRAM:
|
|
if (default_protocol_dgram(protocol))
|
|
return SECCLASS_UDP_SOCKET;
|
|
else
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
case SOCK_DCCP:
|
|
return SECCLASS_DCCP_SOCKET;
|
|
default:
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
}
|
|
break;
|
|
case PF_NETLINK:
|
|
switch (protocol) {
|
|
case NETLINK_ROUTE:
|
|
return SECCLASS_NETLINK_ROUTE_SOCKET;
|
|
case NETLINK_FIREWALL:
|
|
return SECCLASS_NETLINK_FIREWALL_SOCKET;
|
|
case NETLINK_INET_DIAG:
|
|
return SECCLASS_NETLINK_TCPDIAG_SOCKET;
|
|
case NETLINK_NFLOG:
|
|
return SECCLASS_NETLINK_NFLOG_SOCKET;
|
|
case NETLINK_XFRM:
|
|
return SECCLASS_NETLINK_XFRM_SOCKET;
|
|
case NETLINK_SELINUX:
|
|
return SECCLASS_NETLINK_SELINUX_SOCKET;
|
|
case NETLINK_AUDIT:
|
|
return SECCLASS_NETLINK_AUDIT_SOCKET;
|
|
case NETLINK_IP6_FW:
|
|
return SECCLASS_NETLINK_IP6FW_SOCKET;
|
|
case NETLINK_DNRTMSG:
|
|
return SECCLASS_NETLINK_DNRT_SOCKET;
|
|
case NETLINK_KOBJECT_UEVENT:
|
|
return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
|
|
default:
|
|
return SECCLASS_NETLINK_SOCKET;
|
|
}
|
|
case PF_PACKET:
|
|
return SECCLASS_PACKET_SOCKET;
|
|
case PF_KEY:
|
|
return SECCLASS_KEY_SOCKET;
|
|
case PF_APPLETALK:
|
|
return SECCLASS_APPLETALK_SOCKET;
|
|
}
|
|
|
|
return SECCLASS_SOCKET;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static int selinux_proc_get_sid(struct dentry *dentry,
|
|
u16 tclass,
|
|
u32 *sid)
|
|
{
|
|
int rc;
|
|
char *buffer, *path;
|
|
|
|
buffer = (char *)__get_free_page(GFP_KERNEL);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
|
|
path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
|
|
if (IS_ERR(path))
|
|
rc = PTR_ERR(path);
|
|
else {
|
|
/* each process gets a /proc/PID/ entry. Strip off the
|
|
* PID part to get a valid selinux labeling.
|
|
* e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
|
|
while (path[1] >= '0' && path[1] <= '9') {
|
|
path[1] = '/';
|
|
path++;
|
|
}
|
|
rc = security_genfs_sid("proc", path, tclass, sid);
|
|
}
|
|
free_page((unsigned long)buffer);
|
|
return rc;
|
|
}
|
|
#else
|
|
static int selinux_proc_get_sid(struct dentry *dentry,
|
|
u16 tclass,
|
|
u32 *sid)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
/* The inode's security attributes must be initialized before first use. */
|
|
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
|
|
{
|
|
struct superblock_security_struct *sbsec = NULL;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 sid;
|
|
struct dentry *dentry;
|
|
#define INITCONTEXTLEN 255
|
|
char *context = NULL;
|
|
unsigned len = 0;
|
|
int rc = 0;
|
|
|
|
if (isec->initialized)
|
|
goto out;
|
|
|
|
mutex_lock(&isec->lock);
|
|
if (isec->initialized)
|
|
goto out_unlock;
|
|
|
|
sbsec = inode->i_sb->s_security;
|
|
if (!(sbsec->flags & SE_SBINITIALIZED)) {
|
|
/* Defer initialization until selinux_complete_init,
|
|
after the initial policy is loaded and the security
|
|
server is ready to handle calls. */
|
|
spin_lock(&sbsec->isec_lock);
|
|
if (list_empty(&isec->list))
|
|
list_add(&isec->list, &sbsec->isec_head);
|
|
spin_unlock(&sbsec->isec_lock);
|
|
goto out_unlock;
|
|
}
|
|
|
|
switch (sbsec->behavior) {
|
|
case SECURITY_FS_USE_XATTR:
|
|
if (!inode->i_op->getxattr) {
|
|
isec->sid = sbsec->def_sid;
|
|
break;
|
|
}
|
|
|
|
/* Need a dentry, since the xattr API requires one.
|
|
Life would be simpler if we could just pass the inode. */
|
|
if (opt_dentry) {
|
|
/* Called from d_instantiate or d_splice_alias. */
|
|
dentry = dget(opt_dentry);
|
|
} else {
|
|
/* Called from selinux_complete_init, try to find a dentry. */
|
|
dentry = d_find_alias(inode);
|
|
}
|
|
if (!dentry) {
|
|
/*
|
|
* this is can be hit on boot when a file is accessed
|
|
* before the policy is loaded. When we load policy we
|
|
* may find inodes that have no dentry on the
|
|
* sbsec->isec_head list. No reason to complain as these
|
|
* will get fixed up the next time we go through
|
|
* inode_doinit with a dentry, before these inodes could
|
|
* be used again by userspace.
|
|
*/
|
|
goto out_unlock;
|
|
}
|
|
|
|
len = INITCONTEXTLEN;
|
|
context = kmalloc(len+1, GFP_NOFS);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
dput(dentry);
|
|
goto out_unlock;
|
|
}
|
|
context[len] = '\0';
|
|
rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
|
|
context, len);
|
|
if (rc == -ERANGE) {
|
|
kfree(context);
|
|
|
|
/* Need a larger buffer. Query for the right size. */
|
|
rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
|
|
NULL, 0);
|
|
if (rc < 0) {
|
|
dput(dentry);
|
|
goto out_unlock;
|
|
}
|
|
len = rc;
|
|
context = kmalloc(len+1, GFP_NOFS);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
dput(dentry);
|
|
goto out_unlock;
|
|
}
|
|
context[len] = '\0';
|
|
rc = inode->i_op->getxattr(dentry,
|
|
XATTR_NAME_SELINUX,
|
|
context, len);
|
|
}
|
|
dput(dentry);
|
|
if (rc < 0) {
|
|
if (rc != -ENODATA) {
|
|
printk(KERN_WARNING "SELinux: %s: getxattr returned "
|
|
"%d for dev=%s ino=%ld\n", __func__,
|
|
-rc, inode->i_sb->s_id, inode->i_ino);
|
|
kfree(context);
|
|
goto out_unlock;
|
|
}
|
|
/* Map ENODATA to the default file SID */
|
|
sid = sbsec->def_sid;
|
|
rc = 0;
|
|
} else {
|
|
rc = security_context_to_sid_default(context, rc, &sid,
|
|
sbsec->def_sid,
|
|
GFP_NOFS);
|
|
if (rc) {
|
|
char *dev = inode->i_sb->s_id;
|
|
unsigned long ino = inode->i_ino;
|
|
|
|
if (rc == -EINVAL) {
|
|
if (printk_ratelimit())
|
|
printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
|
|
"context=%s. This indicates you may need to relabel the inode or the "
|
|
"filesystem in question.\n", ino, dev, context);
|
|
} else {
|
|
printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
|
|
"returned %d for dev=%s ino=%ld\n",
|
|
__func__, context, -rc, dev, ino);
|
|
}
|
|
kfree(context);
|
|
/* Leave with the unlabeled SID */
|
|
rc = 0;
|
|
break;
|
|
}
|
|
}
|
|
kfree(context);
|
|
isec->sid = sid;
|
|
break;
|
|
case SECURITY_FS_USE_TASK:
|
|
isec->sid = isec->task_sid;
|
|
break;
|
|
case SECURITY_FS_USE_TRANS:
|
|
/* Default to the fs SID. */
|
|
isec->sid = sbsec->sid;
|
|
|
|
/* Try to obtain a transition SID. */
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
rc = security_transition_sid(isec->task_sid, sbsec->sid,
|
|
isec->sclass, NULL, &sid);
|
|
if (rc)
|
|
goto out_unlock;
|
|
isec->sid = sid;
|
|
break;
|
|
case SECURITY_FS_USE_MNTPOINT:
|
|
isec->sid = sbsec->mntpoint_sid;
|
|
break;
|
|
default:
|
|
/* Default to the fs superblock SID. */
|
|
isec->sid = sbsec->sid;
|
|
|
|
if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
|
|
if (opt_dentry) {
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
rc = selinux_proc_get_sid(opt_dentry,
|
|
isec->sclass,
|
|
&sid);
|
|
if (rc)
|
|
goto out_unlock;
|
|
isec->sid = sid;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
isec->initialized = 1;
|
|
|
|
out_unlock:
|
|
mutex_unlock(&isec->lock);
|
|
out:
|
|
if (isec->sclass == SECCLASS_FILE)
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
return rc;
|
|
}
|
|
|
|
/* Convert a Linux signal to an access vector. */
|
|
static inline u32 signal_to_av(int sig)
|
|
{
|
|
u32 perm = 0;
|
|
|
|
switch (sig) {
|
|
case SIGCHLD:
|
|
/* Commonly granted from child to parent. */
|
|
perm = PROCESS__SIGCHLD;
|
|
break;
|
|
case SIGKILL:
|
|
/* Cannot be caught or ignored */
|
|
perm = PROCESS__SIGKILL;
|
|
break;
|
|
case SIGSTOP:
|
|
/* Cannot be caught or ignored */
|
|
perm = PROCESS__SIGSTOP;
|
|
break;
|
|
default:
|
|
/* All other signals. */
|
|
perm = PROCESS__SIGNAL;
|
|
break;
|
|
}
|
|
|
|
return perm;
|
|
}
|
|
|
|
/*
|
|
* Check permission between a pair of credentials
|
|
* fork check, ptrace check, etc.
|
|
*/
|
|
static int cred_has_perm(const struct cred *actor,
|
|
const struct cred *target,
|
|
u32 perms)
|
|
{
|
|
u32 asid = cred_sid(actor), tsid = cred_sid(target);
|
|
|
|
return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
|
|
}
|
|
|
|
/*
|
|
* Check permission between a pair of tasks, e.g. signal checks,
|
|
* fork check, ptrace check, etc.
|
|
* tsk1 is the actor and tsk2 is the target
|
|
* - this uses the default subjective creds of tsk1
|
|
*/
|
|
static int task_has_perm(const struct task_struct *tsk1,
|
|
const struct task_struct *tsk2,
|
|
u32 perms)
|
|
{
|
|
const struct task_security_struct *__tsec1, *__tsec2;
|
|
u32 sid1, sid2;
|
|
|
|
rcu_read_lock();
|
|
__tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
|
|
__tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
|
|
rcu_read_unlock();
|
|
return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
|
|
}
|
|
|
|
/*
|
|
* Check permission between current and another task, e.g. signal checks,
|
|
* fork check, ptrace check, etc.
|
|
* current is the actor and tsk2 is the target
|
|
* - this uses current's subjective creds
|
|
*/
|
|
static int current_has_perm(const struct task_struct *tsk,
|
|
u32 perms)
|
|
{
|
|
u32 sid, tsid;
|
|
|
|
sid = current_sid();
|
|
tsid = task_sid(tsk);
|
|
return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
|
|
}
|
|
|
|
#if CAP_LAST_CAP > 63
|
|
#error Fix SELinux to handle capabilities > 63.
|
|
#endif
|
|
|
|
/* Check whether a task is allowed to use a capability. */
|
|
static int task_has_capability(struct task_struct *tsk,
|
|
const struct cred *cred,
|
|
int cap, int audit)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct av_decision avd;
|
|
u16 sclass;
|
|
u32 sid = cred_sid(cred);
|
|
u32 av = CAP_TO_MASK(cap);
|
|
int rc;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, CAP);
|
|
ad.tsk = tsk;
|
|
ad.u.cap = cap;
|
|
|
|
switch (CAP_TO_INDEX(cap)) {
|
|
case 0:
|
|
sclass = SECCLASS_CAPABILITY;
|
|
break;
|
|
case 1:
|
|
sclass = SECCLASS_CAPABILITY2;
|
|
break;
|
|
default:
|
|
printk(KERN_ERR
|
|
"SELinux: out of range capability %d\n", cap);
|
|
BUG();
|
|
return -EINVAL;
|
|
}
|
|
|
|
rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
|
|
if (audit == SECURITY_CAP_AUDIT) {
|
|
int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
|
|
if (rc2)
|
|
return rc2;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
/* Check whether a task is allowed to use a system operation. */
|
|
static int task_has_system(struct task_struct *tsk,
|
|
u32 perms)
|
|
{
|
|
u32 sid = task_sid(tsk);
|
|
|
|
return avc_has_perm(sid, SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, perms, NULL);
|
|
}
|
|
|
|
/* Check whether a task has a particular permission to an inode.
|
|
The 'adp' parameter is optional and allows other audit
|
|
data to be passed (e.g. the dentry). */
|
|
static int inode_has_perm(const struct cred *cred,
|
|
struct inode *inode,
|
|
u32 perms,
|
|
struct common_audit_data *adp,
|
|
unsigned flags)
|
|
{
|
|
struct inode_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid;
|
|
|
|
validate_creds(cred);
|
|
|
|
if (unlikely(IS_PRIVATE(inode)))
|
|
return 0;
|
|
|
|
sid = cred_sid(cred);
|
|
isec = inode->i_security;
|
|
|
|
if (!adp) {
|
|
adp = &ad;
|
|
COMMON_AUDIT_DATA_INIT(&ad, INODE);
|
|
ad.u.inode = inode;
|
|
}
|
|
|
|
return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
|
|
}
|
|
|
|
/* Same as inode_has_perm, but pass explicit audit data containing
|
|
the dentry to help the auditing code to more easily generate the
|
|
pathname if needed. */
|
|
static inline int dentry_has_perm(const struct cred *cred,
|
|
struct dentry *dentry,
|
|
u32 av)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct common_audit_data ad;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = dentry;
|
|
return inode_has_perm(cred, inode, av, &ad, 0);
|
|
}
|
|
|
|
/* Same as inode_has_perm, but pass explicit audit data containing
|
|
the path to help the auditing code to more easily generate the
|
|
pathname if needed. */
|
|
static inline int path_has_perm(const struct cred *cred,
|
|
struct path *path,
|
|
u32 av)
|
|
{
|
|
struct inode *inode = path->dentry->d_inode;
|
|
struct common_audit_data ad;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, PATH);
|
|
ad.u.path = *path;
|
|
return inode_has_perm(cred, inode, av, &ad, 0);
|
|
}
|
|
|
|
/* Check whether a task can use an open file descriptor to
|
|
access an inode in a given way. Check access to the
|
|
descriptor itself, and then use dentry_has_perm to
|
|
check a particular permission to the file.
|
|
Access to the descriptor is implicitly granted if it
|
|
has the same SID as the process. If av is zero, then
|
|
access to the file is not checked, e.g. for cases
|
|
where only the descriptor is affected like seek. */
|
|
static int file_has_perm(const struct cred *cred,
|
|
struct file *file,
|
|
u32 av)
|
|
{
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct common_audit_data ad;
|
|
u32 sid = cred_sid(cred);
|
|
int rc;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, PATH);
|
|
ad.u.path = file->f_path;
|
|
|
|
if (sid != fsec->sid) {
|
|
rc = avc_has_perm(sid, fsec->sid,
|
|
SECCLASS_FD,
|
|
FD__USE,
|
|
&ad);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
/* av is zero if only checking access to the descriptor. */
|
|
rc = 0;
|
|
if (av)
|
|
rc = inode_has_perm(cred, inode, av, &ad, 0);
|
|
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/* Check whether a task can create a file. */
|
|
static int may_create(struct inode *dir,
|
|
struct dentry *dentry,
|
|
u16 tclass)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct inode_security_struct *dsec;
|
|
struct superblock_security_struct *sbsec;
|
|
u32 sid, newsid;
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
dsec = dir->i_security;
|
|
sbsec = dir->i_sb->s_security;
|
|
|
|
sid = tsec->sid;
|
|
newsid = tsec->create_sid;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = dentry;
|
|
|
|
rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
|
|
DIR__ADD_NAME | DIR__SEARCH,
|
|
&ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
|
|
rc = security_transition_sid(sid, dsec->sid, tclass,
|
|
&dentry->d_name, &newsid);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(newsid, sbsec->sid,
|
|
SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
/* Check whether a task can create a key. */
|
|
static int may_create_key(u32 ksid,
|
|
struct task_struct *ctx)
|
|
{
|
|
u32 sid = task_sid(ctx);
|
|
|
|
return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
|
|
}
|
|
|
|
#define MAY_LINK 0
|
|
#define MAY_UNLINK 1
|
|
#define MAY_RMDIR 2
|
|
|
|
/* Check whether a task can link, unlink, or rmdir a file/directory. */
|
|
static int may_link(struct inode *dir,
|
|
struct dentry *dentry,
|
|
int kind)
|
|
|
|
{
|
|
struct inode_security_struct *dsec, *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
u32 av;
|
|
int rc;
|
|
|
|
dsec = dir->i_security;
|
|
isec = dentry->d_inode->i_security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = dentry;
|
|
|
|
av = DIR__SEARCH;
|
|
av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
|
|
rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
switch (kind) {
|
|
case MAY_LINK:
|
|
av = FILE__LINK;
|
|
break;
|
|
case MAY_UNLINK:
|
|
av = FILE__UNLINK;
|
|
break;
|
|
case MAY_RMDIR:
|
|
av = DIR__RMDIR;
|
|
break;
|
|
default:
|
|
printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
|
|
__func__, kind);
|
|
return 0;
|
|
}
|
|
|
|
rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
|
|
return rc;
|
|
}
|
|
|
|
static inline int may_rename(struct inode *old_dir,
|
|
struct dentry *old_dentry,
|
|
struct inode *new_dir,
|
|
struct dentry *new_dentry)
|
|
{
|
|
struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
u32 av;
|
|
int old_is_dir, new_is_dir;
|
|
int rc;
|
|
|
|
old_dsec = old_dir->i_security;
|
|
old_isec = old_dentry->d_inode->i_security;
|
|
old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
|
|
new_dsec = new_dir->i_security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
|
|
ad.u.dentry = old_dentry;
|
|
rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
|
|
DIR__REMOVE_NAME | DIR__SEARCH, &ad);
|
|
if (rc)
|
|
return rc;
|
|
rc = avc_has_perm(sid, old_isec->sid,
|
|
old_isec->sclass, FILE__RENAME, &ad);
|
|
if (rc)
|
|
return rc;
|
|
if (old_is_dir && new_dir != old_dir) {
|
|
rc = avc_has_perm(sid, old_isec->sid,
|
|
old_isec->sclass, DIR__REPARENT, &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
ad.u.dentry = new_dentry;
|
|
av = DIR__ADD_NAME | DIR__SEARCH;
|
|
if (new_dentry->d_inode)
|
|
av |= DIR__REMOVE_NAME;
|
|
rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
|
|
if (rc)
|
|
return rc;
|
|
if (new_dentry->d_inode) {
|
|
new_isec = new_dentry->d_inode->i_security;
|
|
new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
|
|
rc = avc_has_perm(sid, new_isec->sid,
|
|
new_isec->sclass,
|
|
(new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Check whether a task can perform a filesystem operation. */
|
|
static int superblock_has_perm(const struct cred *cred,
|
|
struct super_block *sb,
|
|
u32 perms,
|
|
struct common_audit_data *ad)
|
|
{
|
|
struct superblock_security_struct *sbsec;
|
|
u32 sid = cred_sid(cred);
|
|
|
|
sbsec = sb->s_security;
|
|
return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
|
|
}
|
|
|
|
/* Convert a Linux mode and permission mask to an access vector. */
|
|
static inline u32 file_mask_to_av(int mode, int mask)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if ((mode & S_IFMT) != S_IFDIR) {
|
|
if (mask & MAY_EXEC)
|
|
av |= FILE__EXECUTE;
|
|
if (mask & MAY_READ)
|
|
av |= FILE__READ;
|
|
|
|
if (mask & MAY_APPEND)
|
|
av |= FILE__APPEND;
|
|
else if (mask & MAY_WRITE)
|
|
av |= FILE__WRITE;
|
|
|
|
} else {
|
|
if (mask & MAY_EXEC)
|
|
av |= DIR__SEARCH;
|
|
if (mask & MAY_WRITE)
|
|
av |= DIR__WRITE;
|
|
if (mask & MAY_READ)
|
|
av |= DIR__READ;
|
|
}
|
|
|
|
return av;
|
|
}
|
|
|
|
/* Convert a Linux file to an access vector. */
|
|
static inline u32 file_to_av(struct file *file)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if (file->f_mode & FMODE_READ)
|
|
av |= FILE__READ;
|
|
if (file->f_mode & FMODE_WRITE) {
|
|
if (file->f_flags & O_APPEND)
|
|
av |= FILE__APPEND;
|
|
else
|
|
av |= FILE__WRITE;
|
|
}
|
|
if (!av) {
|
|
/*
|
|
* Special file opened with flags 3 for ioctl-only use.
|
|
*/
|
|
av = FILE__IOCTL;
|
|
}
|
|
|
|
return av;
|
|
}
|
|
|
|
/*
|
|
* Convert a file to an access vector and include the correct open
|
|
* open permission.
|
|
*/
|
|
static inline u32 open_file_to_av(struct file *file)
|
|
{
|
|
u32 av = file_to_av(file);
|
|
|
|
if (selinux_policycap_openperm)
|
|
av |= FILE__OPEN;
|
|
|
|
return av;
|
|
}
|
|
|
|
/* Hook functions begin here. */
|
|
|
|
static int selinux_ptrace_access_check(struct task_struct *child,
|
|
unsigned int mode)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_ptrace_access_check(child, mode);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (mode == PTRACE_MODE_READ) {
|
|
u32 sid = current_sid();
|
|
u32 csid = task_sid(child);
|
|
return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
|
|
}
|
|
|
|
return current_has_perm(child, PROCESS__PTRACE);
|
|
}
|
|
|
|
static int selinux_ptrace_traceme(struct task_struct *parent)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_ptrace_traceme(parent);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return task_has_perm(parent, current, PROCESS__PTRACE);
|
|
}
|
|
|
|
static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
|
|
kernel_cap_t *inheritable, kernel_cap_t *permitted)
|
|
{
|
|
int error;
|
|
|
|
error = current_has_perm(target, PROCESS__GETCAP);
|
|
if (error)
|
|
return error;
|
|
|
|
return cap_capget(target, effective, inheritable, permitted);
|
|
}
|
|
|
|
static int selinux_capset(struct cred *new, const struct cred *old,
|
|
const kernel_cap_t *effective,
|
|
const kernel_cap_t *inheritable,
|
|
const kernel_cap_t *permitted)
|
|
{
|
|
int error;
|
|
|
|
error = cap_capset(new, old,
|
|
effective, inheritable, permitted);
|
|
if (error)
|
|
return error;
|
|
|
|
return cred_has_perm(old, new, PROCESS__SETCAP);
|
|
}
|
|
|
|
/*
|
|
* (This comment used to live with the selinux_task_setuid hook,
|
|
* which was removed).
|
|
*
|
|
* Since setuid only affects the current process, and since the SELinux
|
|
* controls are not based on the Linux identity attributes, SELinux does not
|
|
* need to control this operation. However, SELinux does control the use of
|
|
* the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
|
|
*/
|
|
|
|
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
|
|
struct user_namespace *ns, int cap, int audit)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_capable(tsk, cred, ns, cap, audit);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return task_has_capability(tsk, cred, cap, audit);
|
|
}
|
|
|
|
static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int rc = 0;
|
|
|
|
if (!sb)
|
|
return 0;
|
|
|
|
switch (cmds) {
|
|
case Q_SYNC:
|
|
case Q_QUOTAON:
|
|
case Q_QUOTAOFF:
|
|
case Q_SETINFO:
|
|
case Q_SETQUOTA:
|
|
rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
|
|
break;
|
|
case Q_GETFMT:
|
|
case Q_GETINFO:
|
|
case Q_GETQUOTA:
|
|
rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
|
|
break;
|
|
default:
|
|
rc = 0; /* let the kernel handle invalid cmds */
|
|
break;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_quota_on(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__QUOTAON);
|
|
}
|
|
|
|
static int selinux_syslog(int type)
|
|
{
|
|
int rc;
|
|
|
|
switch (type) {
|
|
case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
|
|
case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
|
|
rc = task_has_system(current, SYSTEM__SYSLOG_READ);
|
|
break;
|
|
case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
|
|
case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
|
|
/* Set level of messages printed to console */
|
|
case SYSLOG_ACTION_CONSOLE_LEVEL:
|
|
rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
|
|
break;
|
|
case SYSLOG_ACTION_CLOSE: /* Close log */
|
|
case SYSLOG_ACTION_OPEN: /* Open log */
|
|
case SYSLOG_ACTION_READ: /* Read from log */
|
|
case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
|
|
case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
|
|
default:
|
|
rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
|
|
break;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Check that a process has enough memory to allocate a new virtual
|
|
* mapping. 0 means there is enough memory for the allocation to
|
|
* succeed and -ENOMEM implies there is not.
|
|
*
|
|
* Do not audit the selinux permission check, as this is applied to all
|
|
* processes that allocate mappings.
|
|
*/
|
|
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
|
|
{
|
|
int rc, cap_sys_admin = 0;
|
|
|
|
rc = selinux_capable(current, current_cred(),
|
|
&init_user_ns, CAP_SYS_ADMIN,
|
|
SECURITY_CAP_NOAUDIT);
|
|
if (rc == 0)
|
|
cap_sys_admin = 1;
|
|
|
|
return __vm_enough_memory(mm, pages, cap_sys_admin);
|
|
}
|
|
|
|
/* binprm security operations */
|
|
|
|
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
|
|
{
|
|
const struct task_security_struct *old_tsec;
|
|
struct task_security_struct *new_tsec;
|
|
struct inode_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
struct inode *inode = bprm->file->f_path.dentry->d_inode;
|
|
int rc;
|
|
|
|
rc = cap_bprm_set_creds(bprm);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* SELinux context only depends on initial program or script and not
|
|
* the script interpreter */
|
|
if (bprm->cred_prepared)
|
|
return 0;
|
|
|
|
old_tsec = current_security();
|
|
new_tsec = bprm->cred->security;
|
|
isec = inode->i_security;
|
|
|
|
/* Default to the current task SID. */
|
|
new_tsec->sid = old_tsec->sid;
|
|
new_tsec->osid = old_tsec->sid;
|
|
|
|
/* Reset fs, key, and sock SIDs on execve. */
|
|
new_tsec->create_sid = 0;
|
|
new_tsec->keycreate_sid = 0;
|
|
new_tsec->sockcreate_sid = 0;
|
|
|
|
if (old_tsec->exec_sid) {
|
|
new_tsec->sid = old_tsec->exec_sid;
|
|
/* Reset exec SID on execve. */
|
|
new_tsec->exec_sid = 0;
|
|
} else {
|
|
/* Check for a default transition on this program. */
|
|
rc = security_transition_sid(old_tsec->sid, isec->sid,
|
|
SECCLASS_PROCESS, NULL,
|
|
&new_tsec->sid);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, PATH);
|
|
ad.u.path = bprm->file->f_path;
|
|
|
|
if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
|
|
new_tsec->sid = old_tsec->sid;
|
|
|
|
if (new_tsec->sid == old_tsec->sid) {
|
|
rc = avc_has_perm(old_tsec->sid, isec->sid,
|
|
SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
|
|
if (rc)
|
|
return rc;
|
|
} else {
|
|
/* Check permissions for the transition. */
|
|
rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(new_tsec->sid, isec->sid,
|
|
SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Check for shared state */
|
|
if (bprm->unsafe & LSM_UNSAFE_SHARE) {
|
|
rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__SHARE,
|
|
NULL);
|
|
if (rc)
|
|
return -EPERM;
|
|
}
|
|
|
|
/* Make sure that anyone attempting to ptrace over a task that
|
|
* changes its SID has the appropriate permit */
|
|
if (bprm->unsafe &
|
|
(LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
|
|
struct task_struct *tracer;
|
|
struct task_security_struct *sec;
|
|
u32 ptsid = 0;
|
|
|
|
rcu_read_lock();
|
|
tracer = tracehook_tracer_task(current);
|
|
if (likely(tracer != NULL)) {
|
|
sec = __task_cred(tracer)->security;
|
|
ptsid = sec->sid;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (ptsid != 0) {
|
|
rc = avc_has_perm(ptsid, new_tsec->sid,
|
|
SECCLASS_PROCESS,
|
|
PROCESS__PTRACE, NULL);
|
|
if (rc)
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
/* Clear any possibly unsafe personality bits on exec: */
|
|
bprm->per_clear |= PER_CLEAR_ON_SETID;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
u32 sid, osid;
|
|
int atsecure = 0;
|
|
|
|
sid = tsec->sid;
|
|
osid = tsec->osid;
|
|
|
|
if (osid != sid) {
|
|
/* Enable secure mode for SIDs transitions unless
|
|
the noatsecure permission is granted between
|
|
the two SIDs, i.e. ahp returns 0. */
|
|
atsecure = avc_has_perm(osid, sid,
|
|
SECCLASS_PROCESS,
|
|
PROCESS__NOATSECURE, NULL);
|
|
}
|
|
|
|
return (atsecure || cap_bprm_secureexec(bprm));
|
|
}
|
|
|
|
extern struct vfsmount *selinuxfs_mount;
|
|
extern struct dentry *selinux_null;
|
|
|
|
/* Derived from fs/exec.c:flush_old_files. */
|
|
static inline void flush_unauthorized_files(const struct cred *cred,
|
|
struct files_struct *files)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct file *file, *devnull = NULL;
|
|
struct tty_struct *tty;
|
|
struct fdtable *fdt;
|
|
long j = -1;
|
|
int drop_tty = 0;
|
|
|
|
tty = get_current_tty();
|
|
if (tty) {
|
|
spin_lock(&tty_files_lock);
|
|
if (!list_empty(&tty->tty_files)) {
|
|
struct tty_file_private *file_priv;
|
|
struct inode *inode;
|
|
|
|
/* Revalidate access to controlling tty.
|
|
Use inode_has_perm on the tty inode directly rather
|
|
than using file_has_perm, as this particular open
|
|
file may belong to another process and we are only
|
|
interested in the inode-based check here. */
|
|
file_priv = list_first_entry(&tty->tty_files,
|
|
struct tty_file_private, list);
|
|
file = file_priv->file;
|
|
inode = file->f_path.dentry->d_inode;
|
|
if (inode_has_perm(cred, inode,
|
|
FILE__READ | FILE__WRITE, NULL, 0)) {
|
|
drop_tty = 1;
|
|
}
|
|
}
|
|
spin_unlock(&tty_files_lock);
|
|
tty_kref_put(tty);
|
|
}
|
|
/* Reset controlling tty. */
|
|
if (drop_tty)
|
|
no_tty();
|
|
|
|
/* Revalidate access to inherited open files. */
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, INODE);
|
|
|
|
spin_lock(&files->file_lock);
|
|
for (;;) {
|
|
unsigned long set, i;
|
|
int fd;
|
|
|
|
j++;
|
|
i = j * __NFDBITS;
|
|
fdt = files_fdtable(files);
|
|
if (i >= fdt->max_fds)
|
|
break;
|
|
set = fdt->open_fds->fds_bits[j];
|
|
if (!set)
|
|
continue;
|
|
spin_unlock(&files->file_lock);
|
|
for ( ; set ; i++, set >>= 1) {
|
|
if (set & 1) {
|
|
file = fget(i);
|
|
if (!file)
|
|
continue;
|
|
if (file_has_perm(cred,
|
|
file,
|
|
file_to_av(file))) {
|
|
sys_close(i);
|
|
fd = get_unused_fd();
|
|
if (fd != i) {
|
|
if (fd >= 0)
|
|
put_unused_fd(fd);
|
|
fput(file);
|
|
continue;
|
|
}
|
|
if (devnull) {
|
|
get_file(devnull);
|
|
} else {
|
|
devnull = dentry_open(
|
|
dget(selinux_null),
|
|
mntget(selinuxfs_mount),
|
|
O_RDWR, cred);
|
|
if (IS_ERR(devnull)) {
|
|
devnull = NULL;
|
|
put_unused_fd(fd);
|
|
fput(file);
|
|
continue;
|
|
}
|
|
}
|
|
fd_install(fd, devnull);
|
|
}
|
|
fput(file);
|
|
}
|
|
}
|
|
spin_lock(&files->file_lock);
|
|
|
|
}
|
|
spin_unlock(&files->file_lock);
|
|
}
|
|
|
|
/*
|
|
* Prepare a process for imminent new credential changes due to exec
|
|
*/
|
|
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
|
|
{
|
|
struct task_security_struct *new_tsec;
|
|
struct rlimit *rlim, *initrlim;
|
|
int rc, i;
|
|
|
|
new_tsec = bprm->cred->security;
|
|
if (new_tsec->sid == new_tsec->osid)
|
|
return;
|
|
|
|
/* Close files for which the new task SID is not authorized. */
|
|
flush_unauthorized_files(bprm->cred, current->files);
|
|
|
|
/* Always clear parent death signal on SID transitions. */
|
|
current->pdeath_signal = 0;
|
|
|
|
/* Check whether the new SID can inherit resource limits from the old
|
|
* SID. If not, reset all soft limits to the lower of the current
|
|
* task's hard limit and the init task's soft limit.
|
|
*
|
|
* Note that the setting of hard limits (even to lower them) can be
|
|
* controlled by the setrlimit check. The inclusion of the init task's
|
|
* soft limit into the computation is to avoid resetting soft limits
|
|
* higher than the default soft limit for cases where the default is
|
|
* lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
|
|
*/
|
|
rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
|
|
PROCESS__RLIMITINH, NULL);
|
|
if (rc) {
|
|
/* protect against do_prlimit() */
|
|
task_lock(current);
|
|
for (i = 0; i < RLIM_NLIMITS; i++) {
|
|
rlim = current->signal->rlim + i;
|
|
initrlim = init_task.signal->rlim + i;
|
|
rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
|
|
}
|
|
task_unlock(current);
|
|
update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Clean up the process immediately after the installation of new credentials
|
|
* due to exec
|
|
*/
|
|
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct itimerval itimer;
|
|
u32 osid, sid;
|
|
int rc, i;
|
|
|
|
osid = tsec->osid;
|
|
sid = tsec->sid;
|
|
|
|
if (sid == osid)
|
|
return;
|
|
|
|
/* Check whether the new SID can inherit signal state from the old SID.
|
|
* If not, clear itimers to avoid subsequent signal generation and
|
|
* flush and unblock signals.
|
|
*
|
|
* This must occur _after_ the task SID has been updated so that any
|
|
* kill done after the flush will be checked against the new SID.
|
|
*/
|
|
rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
|
|
if (rc) {
|
|
memset(&itimer, 0, sizeof itimer);
|
|
for (i = 0; i < 3; i++)
|
|
do_setitimer(i, &itimer, NULL);
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
|
|
__flush_signals(current);
|
|
flush_signal_handlers(current, 1);
|
|
sigemptyset(¤t->blocked);
|
|
}
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
}
|
|
|
|
/* Wake up the parent if it is waiting so that it can recheck
|
|
* wait permission to the new task SID. */
|
|
read_lock(&tasklist_lock);
|
|
__wake_up_parent(current, current->real_parent);
|
|
read_unlock(&tasklist_lock);
|
|
}
|
|
|
|
/* superblock security operations */
|
|
|
|
static int selinux_sb_alloc_security(struct super_block *sb)
|
|
{
|
|
return superblock_alloc_security(sb);
|
|
}
|
|
|
|
static void selinux_sb_free_security(struct super_block *sb)
|
|
{
|
|
superblock_free_security(sb);
|
|
}
|
|
|
|
static inline int match_prefix(char *prefix, int plen, char *option, int olen)
|
|
{
|
|
if (plen > olen)
|
|
return 0;
|
|
|
|
return !memcmp(prefix, option, plen);
|
|
}
|
|
|
|
static inline int selinux_option(char *option, int len)
|
|
{
|
|
return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
|
|
match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
|
|
}
|
|
|
|
static inline void take_option(char **to, char *from, int *first, int len)
|
|
{
|
|
if (!*first) {
|
|
**to = ',';
|
|
*to += 1;
|
|
} else
|
|
*first = 0;
|
|
memcpy(*to, from, len);
|
|
*to += len;
|
|
}
|
|
|
|
static inline void take_selinux_option(char **to, char *from, int *first,
|
|
int len)
|
|
{
|
|
int current_size = 0;
|
|
|
|
if (!*first) {
|
|
**to = '|';
|
|
*to += 1;
|
|
} else
|
|
*first = 0;
|
|
|
|
while (current_size < len) {
|
|
if (*from != '"') {
|
|
**to = *from;
|
|
*to += 1;
|
|
}
|
|
from += 1;
|
|
current_size += 1;
|
|
}
|
|
}
|
|
|
|
static int selinux_sb_copy_data(char *orig, char *copy)
|
|
{
|
|
int fnosec, fsec, rc = 0;
|
|
char *in_save, *in_curr, *in_end;
|
|
char *sec_curr, *nosec_save, *nosec;
|
|
int open_quote = 0;
|
|
|
|
in_curr = orig;
|
|
sec_curr = copy;
|
|
|
|
nosec = (char *)get_zeroed_page(GFP_KERNEL);
|
|
if (!nosec) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
nosec_save = nosec;
|
|
fnosec = fsec = 1;
|
|
in_save = in_end = orig;
|
|
|
|
do {
|
|
if (*in_end == '"')
|
|
open_quote = !open_quote;
|
|
if ((*in_end == ',' && open_quote == 0) ||
|
|
*in_end == '\0') {
|
|
int len = in_end - in_curr;
|
|
|
|
if (selinux_option(in_curr, len))
|
|
take_selinux_option(&sec_curr, in_curr, &fsec, len);
|
|
else
|
|
take_option(&nosec, in_curr, &fnosec, len);
|
|
|
|
in_curr = in_end + 1;
|
|
}
|
|
} while (*in_end++);
|
|
|
|
strcpy(in_save, nosec_save);
|
|
free_page((unsigned long)nosec_save);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_sb_remount(struct super_block *sb, void *data)
|
|
{
|
|
int rc, i, *flags;
|
|
struct security_mnt_opts opts;
|
|
char *secdata, **mount_options;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
return 0;
|
|
|
|
if (!data)
|
|
return 0;
|
|
|
|
if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
|
|
return 0;
|
|
|
|
security_init_mnt_opts(&opts);
|
|
secdata = alloc_secdata();
|
|
if (!secdata)
|
|
return -ENOMEM;
|
|
rc = selinux_sb_copy_data(data, secdata);
|
|
if (rc)
|
|
goto out_free_secdata;
|
|
|
|
rc = selinux_parse_opts_str(secdata, &opts);
|
|
if (rc)
|
|
goto out_free_secdata;
|
|
|
|
mount_options = opts.mnt_opts;
|
|
flags = opts.mnt_opts_flags;
|
|
|
|
for (i = 0; i < opts.num_mnt_opts; i++) {
|
|
u32 sid;
|
|
size_t len;
|
|
|
|
if (flags[i] == SE_SBLABELSUPP)
|
|
continue;
|
|
len = strlen(mount_options[i]);
|
|
rc = security_context_to_sid(mount_options[i], len, &sid);
|
|
if (rc) {
|
|
printk(KERN_WARNING "SELinux: security_context_to_sid"
|
|
"(%s) failed for (dev %s, type %s) errno=%d\n",
|
|
mount_options[i], sb->s_id, sb->s_type->name, rc);
|
|
goto out_free_opts;
|
|
}
|
|
rc = -EINVAL;
|
|
switch (flags[i]) {
|
|
case FSCONTEXT_MNT:
|
|
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
case CONTEXT_MNT:
|
|
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
case ROOTCONTEXT_MNT: {
|
|
struct inode_security_struct *root_isec;
|
|
root_isec = sb->s_root->d_inode->i_security;
|
|
|
|
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
}
|
|
case DEFCONTEXT_MNT:
|
|
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
default:
|
|
goto out_free_opts;
|
|
}
|
|
}
|
|
|
|
rc = 0;
|
|
out_free_opts:
|
|
security_free_mnt_opts(&opts);
|
|
out_free_secdata:
|
|
free_secdata(secdata);
|
|
return rc;
|
|
out_bad_option:
|
|
printk(KERN_WARNING "SELinux: unable to change security options "
|
|
"during remount (dev %s, type=%s)\n", sb->s_id,
|
|
sb->s_type->name);
|
|
goto out_free_opts;
|
|
}
|
|
|
|
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
rc = superblock_doinit(sb, data);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Allow all mounts performed by the kernel */
|
|
if (flags & MS_KERNMOUNT)
|
|
return 0;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = sb->s_root;
|
|
return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
|
|
}
|
|
|
|
static int selinux_sb_statfs(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = dentry->d_sb->s_root;
|
|
return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
|
|
}
|
|
|
|
static int selinux_mount(char *dev_name,
|
|
struct path *path,
|
|
char *type,
|
|
unsigned long flags,
|
|
void *data)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
if (flags & MS_REMOUNT)
|
|
return superblock_has_perm(cred, path->mnt->mnt_sb,
|
|
FILESYSTEM__REMOUNT, NULL);
|
|
else
|
|
return path_has_perm(cred, path, FILE__MOUNTON);
|
|
}
|
|
|
|
static int selinux_umount(struct vfsmount *mnt, int flags)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return superblock_has_perm(cred, mnt->mnt_sb,
|
|
FILESYSTEM__UNMOUNT, NULL);
|
|
}
|
|
|
|
/* inode security operations */
|
|
|
|
static int selinux_inode_alloc_security(struct inode *inode)
|
|
{
|
|
return inode_alloc_security(inode);
|
|
}
|
|
|
|
static void selinux_inode_free_security(struct inode *inode)
|
|
{
|
|
inode_free_security(inode);
|
|
}
|
|
|
|
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
|
|
const struct qstr *qstr, char **name,
|
|
void **value, size_t *len)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct inode_security_struct *dsec;
|
|
struct superblock_security_struct *sbsec;
|
|
u32 sid, newsid, clen;
|
|
int rc;
|
|
char *namep = NULL, *context;
|
|
|
|
dsec = dir->i_security;
|
|
sbsec = dir->i_sb->s_security;
|
|
|
|
sid = tsec->sid;
|
|
newsid = tsec->create_sid;
|
|
|
|
if ((sbsec->flags & SE_SBINITIALIZED) &&
|
|
(sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
|
|
newsid = sbsec->mntpoint_sid;
|
|
else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
|
|
rc = security_transition_sid(sid, dsec->sid,
|
|
inode_mode_to_security_class(inode->i_mode),
|
|
qstr, &newsid);
|
|
if (rc) {
|
|
printk(KERN_WARNING "%s: "
|
|
"security_transition_sid failed, rc=%d (dev=%s "
|
|
"ino=%ld)\n",
|
|
__func__,
|
|
-rc, inode->i_sb->s_id, inode->i_ino);
|
|
return rc;
|
|
}
|
|
}
|
|
|
|
/* Possibly defer initialization to selinux_complete_init. */
|
|
if (sbsec->flags & SE_SBINITIALIZED) {
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
isec->sid = newsid;
|
|
isec->initialized = 1;
|
|
}
|
|
|
|
if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (name) {
|
|
namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
|
|
if (!namep)
|
|
return -ENOMEM;
|
|
*name = namep;
|
|
}
|
|
|
|
if (value && len) {
|
|
rc = security_sid_to_context_force(newsid, &context, &clen);
|
|
if (rc) {
|
|
kfree(namep);
|
|
return rc;
|
|
}
|
|
*value = context;
|
|
*len = clen;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_FILE);
|
|
}
|
|
|
|
static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
|
|
{
|
|
return may_link(dir, old_dentry, MAY_LINK);
|
|
}
|
|
|
|
static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
return may_link(dir, dentry, MAY_UNLINK);
|
|
}
|
|
|
|
static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_LNK_FILE);
|
|
}
|
|
|
|
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_DIR);
|
|
}
|
|
|
|
static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
return may_link(dir, dentry, MAY_RMDIR);
|
|
}
|
|
|
|
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
|
|
{
|
|
return may_create(dir, dentry, inode_mode_to_security_class(mode));
|
|
}
|
|
|
|
static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
|
|
struct inode *new_inode, struct dentry *new_dentry)
|
|
{
|
|
return may_rename(old_inode, old_dentry, new_inode, new_dentry);
|
|
}
|
|
|
|
static int selinux_inode_readlink(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__READ);
|
|
}
|
|
|
|
static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__READ);
|
|
}
|
|
|
|
static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
u32 perms;
|
|
bool from_access;
|
|
|
|
from_access = mask & MAY_ACCESS;
|
|
mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
|
|
|
|
/* No permission to check. Existence test. */
|
|
if (!mask)
|
|
return 0;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, INODE);
|
|
ad.u.inode = inode;
|
|
|
|
if (from_access)
|
|
ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
|
|
|
|
perms = file_mask_to_av(inode->i_mode, mask);
|
|
|
|
return inode_has_perm(cred, inode, perms, &ad, flags);
|
|
}
|
|
|
|
static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
unsigned int ia_valid = iattr->ia_valid;
|
|
|
|
/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
|
|
if (ia_valid & ATTR_FORCE) {
|
|
ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
|
|
ATTR_FORCE);
|
|
if (!ia_valid)
|
|
return 0;
|
|
}
|
|
|
|
if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
|
|
ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
|
|
return dentry_has_perm(cred, dentry, FILE__SETATTR);
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__WRITE);
|
|
}
|
|
|
|
static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct path path;
|
|
|
|
path.dentry = dentry;
|
|
path.mnt = mnt;
|
|
|
|
return path_has_perm(cred, &path, FILE__GETATTR);
|
|
}
|
|
|
|
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
if (!strncmp(name, XATTR_SECURITY_PREFIX,
|
|
sizeof XATTR_SECURITY_PREFIX - 1)) {
|
|
if (!strcmp(name, XATTR_NAME_CAPS)) {
|
|
if (!capable(CAP_SETFCAP))
|
|
return -EPERM;
|
|
} else if (!capable(CAP_SYS_ADMIN)) {
|
|
/* A different attribute in the security namespace.
|
|
Restrict to administrator. */
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
/* Not an attribute we recognize, so just check the
|
|
ordinary setattr permission. */
|
|
return dentry_has_perm(cred, dentry, FILE__SETATTR);
|
|
}
|
|
|
|
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size, int flags)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
struct superblock_security_struct *sbsec;
|
|
struct common_audit_data ad;
|
|
u32 newsid, sid = current_sid();
|
|
int rc = 0;
|
|
|
|
if (strcmp(name, XATTR_NAME_SELINUX))
|
|
return selinux_inode_setotherxattr(dentry, name);
|
|
|
|
sbsec = inode->i_sb->s_security;
|
|
if (!(sbsec->flags & SE_SBLABELSUPP))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (!inode_owner_or_capable(inode))
|
|
return -EPERM;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
|
|
ad.u.dentry = dentry;
|
|
|
|
rc = avc_has_perm(sid, isec->sid, isec->sclass,
|
|
FILE__RELABELFROM, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = security_context_to_sid(value, size, &newsid);
|
|
if (rc == -EINVAL) {
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
return rc;
|
|
rc = security_context_to_sid_force(value, size, &newsid);
|
|
}
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(sid, newsid, isec->sclass,
|
|
FILE__RELABELTO, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = security_validate_transition(isec->sid, newsid, sid,
|
|
isec->sclass);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(newsid,
|
|
sbsec->sid,
|
|
SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__ASSOCIATE,
|
|
&ad);
|
|
}
|
|
|
|
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size,
|
|
int flags)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 newsid;
|
|
int rc;
|
|
|
|
if (strcmp(name, XATTR_NAME_SELINUX)) {
|
|
/* Not an attribute we recognize, so nothing to do. */
|
|
return;
|
|
}
|
|
|
|
rc = security_context_to_sid_force(value, size, &newsid);
|
|
if (rc) {
|
|
printk(KERN_ERR "SELinux: unable to map context to SID"
|
|
"for (%s, %lu), rc=%d\n",
|
|
inode->i_sb->s_id, inode->i_ino, -rc);
|
|
return;
|
|
}
|
|
|
|
isec->sid = newsid;
|
|
return;
|
|
}
|
|
|
|
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__GETATTR);
|
|
}
|
|
|
|
static int selinux_inode_listxattr(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__GETATTR);
|
|
}
|
|
|
|
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
|
|
{
|
|
if (strcmp(name, XATTR_NAME_SELINUX))
|
|
return selinux_inode_setotherxattr(dentry, name);
|
|
|
|
/* No one is allowed to remove a SELinux security label.
|
|
You can change the label, but all data must be labeled. */
|
|
return -EACCES;
|
|
}
|
|
|
|
/*
|
|
* Copy the inode security context value to the user.
|
|
*
|
|
* Permission check is handled by selinux_inode_getxattr hook.
|
|
*/
|
|
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
|
|
{
|
|
u32 size;
|
|
int error;
|
|
char *context = NULL;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
|
|
if (strcmp(name, XATTR_SELINUX_SUFFIX))
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* If the caller has CAP_MAC_ADMIN, then get the raw context
|
|
* value even if it is not defined by current policy; otherwise,
|
|
* use the in-core value under current policy.
|
|
* Use the non-auditing forms of the permission checks since
|
|
* getxattr may be called by unprivileged processes commonly
|
|
* and lack of permission just means that we fall back to the
|
|
* in-core context value, not a denial.
|
|
*/
|
|
error = selinux_capable(current, current_cred(),
|
|
&init_user_ns, CAP_MAC_ADMIN,
|
|
SECURITY_CAP_NOAUDIT);
|
|
if (!error)
|
|
error = security_sid_to_context_force(isec->sid, &context,
|
|
&size);
|
|
else
|
|
error = security_sid_to_context(isec->sid, &context, &size);
|
|
if (error)
|
|
return error;
|
|
error = size;
|
|
if (alloc) {
|
|
*buffer = context;
|
|
goto out_nofree;
|
|
}
|
|
kfree(context);
|
|
out_nofree:
|
|
return error;
|
|
}
|
|
|
|
static int selinux_inode_setsecurity(struct inode *inode, const char *name,
|
|
const void *value, size_t size, int flags)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 newsid;
|
|
int rc;
|
|
|
|
if (strcmp(name, XATTR_SELINUX_SUFFIX))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (!value || !size)
|
|
return -EACCES;
|
|
|
|
rc = security_context_to_sid((void *)value, size, &newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec->sid = newsid;
|
|
isec->initialized = 1;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
|
|
{
|
|
const int len = sizeof(XATTR_NAME_SELINUX);
|
|
if (buffer && len <= buffer_size)
|
|
memcpy(buffer, XATTR_NAME_SELINUX, len);
|
|
return len;
|
|
}
|
|
|
|
static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
*secid = isec->sid;
|
|
}
|
|
|
|
/* file security operations */
|
|
|
|
static int selinux_revalidate_file_permission(struct file *file, int mask)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
|
|
/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
|
|
if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
|
|
mask |= MAY_APPEND;
|
|
|
|
return file_has_perm(cred, file,
|
|
file_mask_to_av(inode->i_mode, mask));
|
|
}
|
|
|
|
static int selinux_file_permission(struct file *file, int mask)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 sid = current_sid();
|
|
|
|
if (!mask)
|
|
/* No permission to check. Existence test. */
|
|
return 0;
|
|
|
|
if (sid == fsec->sid && fsec->isid == isec->sid &&
|
|
fsec->pseqno == avc_policy_seqno())
|
|
/* No change since dentry_open check. */
|
|
return 0;
|
|
|
|
return selinux_revalidate_file_permission(file, mask);
|
|
}
|
|
|
|
static int selinux_file_alloc_security(struct file *file)
|
|
{
|
|
return file_alloc_security(file);
|
|
}
|
|
|
|
static void selinux_file_free_security(struct file *file)
|
|
{
|
|
file_free_security(file);
|
|
}
|
|
|
|
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int error = 0;
|
|
|
|
switch (cmd) {
|
|
case FIONREAD:
|
|
/* fall through */
|
|
case FIBMAP:
|
|
/* fall through */
|
|
case FIGETBSZ:
|
|
/* fall through */
|
|
case EXT2_IOC_GETFLAGS:
|
|
/* fall through */
|
|
case EXT2_IOC_GETVERSION:
|
|
error = file_has_perm(cred, file, FILE__GETATTR);
|
|
break;
|
|
|
|
case EXT2_IOC_SETFLAGS:
|
|
/* fall through */
|
|
case EXT2_IOC_SETVERSION:
|
|
error = file_has_perm(cred, file, FILE__SETATTR);
|
|
break;
|
|
|
|
/* sys_ioctl() checks */
|
|
case FIONBIO:
|
|
/* fall through */
|
|
case FIOASYNC:
|
|
error = file_has_perm(cred, file, 0);
|
|
break;
|
|
|
|
case KDSKBENT:
|
|
case KDSKBSENT:
|
|
error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
|
|
SECURITY_CAP_AUDIT);
|
|
break;
|
|
|
|
/* default case assumes that the command will go
|
|
* to the file's ioctl() function.
|
|
*/
|
|
default:
|
|
error = file_has_perm(cred, file, FILE__IOCTL);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
static int default_noexec;
|
|
|
|
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int rc = 0;
|
|
|
|
if (default_noexec &&
|
|
(prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
|
|
/*
|
|
* We are making executable an anonymous mapping or a
|
|
* private file mapping that will also be writable.
|
|
* This has an additional check.
|
|
*/
|
|
rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
|
|
if (rc)
|
|
goto error;
|
|
}
|
|
|
|
if (file) {
|
|
/* read access is always possible with a mapping */
|
|
u32 av = FILE__READ;
|
|
|
|
/* write access only matters if the mapping is shared */
|
|
if (shared && (prot & PROT_WRITE))
|
|
av |= FILE__WRITE;
|
|
|
|
if (prot & PROT_EXEC)
|
|
av |= FILE__EXECUTE;
|
|
|
|
return file_has_perm(cred, file, av);
|
|
}
|
|
|
|
error:
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_file_mmap(struct file *file, unsigned long reqprot,
|
|
unsigned long prot, unsigned long flags,
|
|
unsigned long addr, unsigned long addr_only)
|
|
{
|
|
int rc = 0;
|
|
u32 sid = current_sid();
|
|
|
|
/*
|
|
* notice that we are intentionally putting the SELinux check before
|
|
* the secondary cap_file_mmap check. This is such a likely attempt
|
|
* at bad behaviour/exploit that we always want to get the AVC, even
|
|
* if DAC would have also denied the operation.
|
|
*/
|
|
if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
|
|
rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
|
|
MEMPROTECT__MMAP_ZERO, NULL);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
/* do DAC check on address space usage */
|
|
rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
|
|
if (rc || addr_only)
|
|
return rc;
|
|
|
|
if (selinux_checkreqprot)
|
|
prot = reqprot;
|
|
|
|
return file_map_prot_check(file, prot,
|
|
(flags & MAP_TYPE) == MAP_SHARED);
|
|
}
|
|
|
|
static int selinux_file_mprotect(struct vm_area_struct *vma,
|
|
unsigned long reqprot,
|
|
unsigned long prot)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
if (selinux_checkreqprot)
|
|
prot = reqprot;
|
|
|
|
if (default_noexec &&
|
|
(prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
|
|
int rc = 0;
|
|
if (vma->vm_start >= vma->vm_mm->start_brk &&
|
|
vma->vm_end <= vma->vm_mm->brk) {
|
|
rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
|
|
} else if (!vma->vm_file &&
|
|
vma->vm_start <= vma->vm_mm->start_stack &&
|
|
vma->vm_end >= vma->vm_mm->start_stack) {
|
|
rc = current_has_perm(current, PROCESS__EXECSTACK);
|
|
} else if (vma->vm_file && vma->anon_vma) {
|
|
/*
|
|
* We are making executable a file mapping that has
|
|
* had some COW done. Since pages might have been
|
|
* written, check ability to execute the possibly
|
|
* modified content. This typically should only
|
|
* occur for text relocations.
|
|
*/
|
|
rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
|
|
}
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
|
|
}
|
|
|
|
static int selinux_file_lock(struct file *file, unsigned int cmd)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return file_has_perm(cred, file, FILE__LOCK);
|
|
}
|
|
|
|
static int selinux_file_fcntl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int err = 0;
|
|
|
|
switch (cmd) {
|
|
case F_SETFL:
|
|
if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
|
|
err = file_has_perm(cred, file, FILE__WRITE);
|
|
break;
|
|
}
|
|
/* fall through */
|
|
case F_SETOWN:
|
|
case F_SETSIG:
|
|
case F_GETFL:
|
|
case F_GETOWN:
|
|
case F_GETSIG:
|
|
/* Just check FD__USE permission */
|
|
err = file_has_perm(cred, file, 0);
|
|
break;
|
|
case F_GETLK:
|
|
case F_SETLK:
|
|
case F_SETLKW:
|
|
#if BITS_PER_LONG == 32
|
|
case F_GETLK64:
|
|
case F_SETLK64:
|
|
case F_SETLKW64:
|
|
#endif
|
|
if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
err = file_has_perm(cred, file, FILE__LOCK);
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_file_set_fowner(struct file *file)
|
|
{
|
|
struct file_security_struct *fsec;
|
|
|
|
fsec = file->f_security;
|
|
fsec->fown_sid = current_sid();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_file_send_sigiotask(struct task_struct *tsk,
|
|
struct fown_struct *fown, int signum)
|
|
{
|
|
struct file *file;
|
|
u32 sid = task_sid(tsk);
|
|
u32 perm;
|
|
struct file_security_struct *fsec;
|
|
|
|
/* struct fown_struct is never outside the context of a struct file */
|
|
file = container_of(fown, struct file, f_owner);
|
|
|
|
fsec = file->f_security;
|
|
|
|
if (!signum)
|
|
perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
|
|
else
|
|
perm = signal_to_av(signum);
|
|
|
|
return avc_has_perm(fsec->fown_sid, sid,
|
|
SECCLASS_PROCESS, perm, NULL);
|
|
}
|
|
|
|
static int selinux_file_receive(struct file *file)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return file_has_perm(cred, file, file_to_av(file));
|
|
}
|
|
|
|
static int selinux_dentry_open(struct file *file, const struct cred *cred)
|
|
{
|
|
struct file_security_struct *fsec;
|
|
struct inode *inode;
|
|
struct inode_security_struct *isec;
|
|
|
|
inode = file->f_path.dentry->d_inode;
|
|
fsec = file->f_security;
|
|
isec = inode->i_security;
|
|
/*
|
|
* Save inode label and policy sequence number
|
|
* at open-time so that selinux_file_permission
|
|
* can determine whether revalidation is necessary.
|
|
* Task label is already saved in the file security
|
|
* struct as its SID.
|
|
*/
|
|
fsec->isid = isec->sid;
|
|
fsec->pseqno = avc_policy_seqno();
|
|
/*
|
|
* Since the inode label or policy seqno may have changed
|
|
* between the selinux_inode_permission check and the saving
|
|
* of state above, recheck that access is still permitted.
|
|
* Otherwise, access might never be revalidated against the
|
|
* new inode label or new policy.
|
|
* This check is not redundant - do not remove.
|
|
*/
|
|
return inode_has_perm(cred, inode, open_file_to_av(file), NULL, 0);
|
|
}
|
|
|
|
/* task security operations */
|
|
|
|
static int selinux_task_create(unsigned long clone_flags)
|
|
{
|
|
return current_has_perm(current, PROCESS__FORK);
|
|
}
|
|
|
|
/*
|
|
* allocate the SELinux part of blank credentials
|
|
*/
|
|
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
|
|
{
|
|
struct task_security_struct *tsec;
|
|
|
|
tsec = kzalloc(sizeof(struct task_security_struct), gfp);
|
|
if (!tsec)
|
|
return -ENOMEM;
|
|
|
|
cred->security = tsec;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* detach and free the LSM part of a set of credentials
|
|
*/
|
|
static void selinux_cred_free(struct cred *cred)
|
|
{
|
|
struct task_security_struct *tsec = cred->security;
|
|
|
|
/*
|
|
* cred->security == NULL if security_cred_alloc_blank() or
|
|
* security_prepare_creds() returned an error.
|
|
*/
|
|
BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
|
|
cred->security = (void *) 0x7UL;
|
|
kfree(tsec);
|
|
}
|
|
|
|
/*
|
|
* prepare a new set of credentials for modification
|
|
*/
|
|
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
|
|
gfp_t gfp)
|
|
{
|
|
const struct task_security_struct *old_tsec;
|
|
struct task_security_struct *tsec;
|
|
|
|
old_tsec = old->security;
|
|
|
|
tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
|
|
if (!tsec)
|
|
return -ENOMEM;
|
|
|
|
new->security = tsec;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* transfer the SELinux data to a blank set of creds
|
|
*/
|
|
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
|
|
{
|
|
const struct task_security_struct *old_tsec = old->security;
|
|
struct task_security_struct *tsec = new->security;
|
|
|
|
*tsec = *old_tsec;
|
|
}
|
|
|
|
/*
|
|
* set the security data for a kernel service
|
|
* - all the creation contexts are set to unlabelled
|
|
*/
|
|
static int selinux_kernel_act_as(struct cred *new, u32 secid)
|
|
{
|
|
struct task_security_struct *tsec = new->security;
|
|
u32 sid = current_sid();
|
|
int ret;
|
|
|
|
ret = avc_has_perm(sid, secid,
|
|
SECCLASS_KERNEL_SERVICE,
|
|
KERNEL_SERVICE__USE_AS_OVERRIDE,
|
|
NULL);
|
|
if (ret == 0) {
|
|
tsec->sid = secid;
|
|
tsec->create_sid = 0;
|
|
tsec->keycreate_sid = 0;
|
|
tsec->sockcreate_sid = 0;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* set the file creation context in a security record to the same as the
|
|
* objective context of the specified inode
|
|
*/
|
|
static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
struct task_security_struct *tsec = new->security;
|
|
u32 sid = current_sid();
|
|
int ret;
|
|
|
|
ret = avc_has_perm(sid, isec->sid,
|
|
SECCLASS_KERNEL_SERVICE,
|
|
KERNEL_SERVICE__CREATE_FILES_AS,
|
|
NULL);
|
|
|
|
if (ret == 0)
|
|
tsec->create_sid = isec->sid;
|
|
return ret;
|
|
}
|
|
|
|
static int selinux_kernel_module_request(char *kmod_name)
|
|
{
|
|
u32 sid;
|
|
struct common_audit_data ad;
|
|
|
|
sid = task_sid(current);
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, KMOD);
|
|
ad.u.kmod_name = kmod_name;
|
|
|
|
return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
|
|
SYSTEM__MODULE_REQUEST, &ad);
|
|
}
|
|
|
|
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
|
|
{
|
|
return current_has_perm(p, PROCESS__SETPGID);
|
|
}
|
|
|
|
static int selinux_task_getpgid(struct task_struct *p)
|
|
{
|
|
return current_has_perm(p, PROCESS__GETPGID);
|
|
}
|
|
|
|
static int selinux_task_getsid(struct task_struct *p)
|
|
{
|
|
return current_has_perm(p, PROCESS__GETSESSION);
|
|
}
|
|
|
|
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
|
|
{
|
|
*secid = task_sid(p);
|
|
}
|
|
|
|
static int selinux_task_setnice(struct task_struct *p, int nice)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_task_setnice(p, nice);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return current_has_perm(p, PROCESS__SETSCHED);
|
|
}
|
|
|
|
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_task_setioprio(p, ioprio);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return current_has_perm(p, PROCESS__SETSCHED);
|
|
}
|
|
|
|
static int selinux_task_getioprio(struct task_struct *p)
|
|
{
|
|
return current_has_perm(p, PROCESS__GETSCHED);
|
|
}
|
|
|
|
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
|
|
struct rlimit *new_rlim)
|
|
{
|
|
struct rlimit *old_rlim = p->signal->rlim + resource;
|
|
|
|
/* Control the ability to change the hard limit (whether
|
|
lowering or raising it), so that the hard limit can
|
|
later be used as a safe reset point for the soft limit
|
|
upon context transitions. See selinux_bprm_committing_creds. */
|
|
if (old_rlim->rlim_max != new_rlim->rlim_max)
|
|
return current_has_perm(p, PROCESS__SETRLIMIT);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_task_setscheduler(struct task_struct *p)
|
|
{
|
|
int rc;
|
|
|
|
rc = cap_task_setscheduler(p);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return current_has_perm(p, PROCESS__SETSCHED);
|
|
}
|
|
|
|
static int selinux_task_getscheduler(struct task_struct *p)
|
|
{
|
|
return current_has_perm(p, PROCESS__GETSCHED);
|
|
}
|
|
|
|
static int selinux_task_movememory(struct task_struct *p)
|
|
{
|
|
return current_has_perm(p, PROCESS__SETSCHED);
|
|
}
|
|
|
|
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
|
|
int sig, u32 secid)
|
|
{
|
|
u32 perm;
|
|
int rc;
|
|
|
|
if (!sig)
|
|
perm = PROCESS__SIGNULL; /* null signal; existence test */
|
|
else
|
|
perm = signal_to_av(sig);
|
|
if (secid)
|
|
rc = avc_has_perm(secid, task_sid(p),
|
|
SECCLASS_PROCESS, perm, NULL);
|
|
else
|
|
rc = current_has_perm(p, perm);
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_task_wait(struct task_struct *p)
|
|
{
|
|
return task_has_perm(p, current, PROCESS__SIGCHLD);
|
|
}
|
|
|
|
static void selinux_task_to_inode(struct task_struct *p,
|
|
struct inode *inode)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 sid = task_sid(p);
|
|
|
|
isec->sid = sid;
|
|
isec->initialized = 1;
|
|
}
|
|
|
|
/* Returns error only if unable to parse addresses */
|
|
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
|
|
struct common_audit_data *ad, u8 *proto)
|
|
{
|
|
int offset, ihlen, ret = -EINVAL;
|
|
struct iphdr _iph, *ih;
|
|
|
|
offset = skb_network_offset(skb);
|
|
ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
|
|
if (ih == NULL)
|
|
goto out;
|
|
|
|
ihlen = ih->ihl * 4;
|
|
if (ihlen < sizeof(_iph))
|
|
goto out;
|
|
|
|
ad->u.net.v4info.saddr = ih->saddr;
|
|
ad->u.net.v4info.daddr = ih->daddr;
|
|
ret = 0;
|
|
|
|
if (proto)
|
|
*proto = ih->protocol;
|
|
|
|
switch (ih->protocol) {
|
|
case IPPROTO_TCP: {
|
|
struct tcphdr _tcph, *th;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
|
|
if (th == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = th->source;
|
|
ad->u.net.dport = th->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_UDP: {
|
|
struct udphdr _udph, *uh;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
|
|
if (uh == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = uh->source;
|
|
ad->u.net.dport = uh->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_DCCP: {
|
|
struct dccp_hdr _dccph, *dh;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
|
|
if (dh == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = dh->dccph_sport;
|
|
ad->u.net.dport = dh->dccph_dport;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
break;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
|
|
/* Returns error only if unable to parse addresses */
|
|
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
|
|
struct common_audit_data *ad, u8 *proto)
|
|
{
|
|
u8 nexthdr;
|
|
int ret = -EINVAL, offset;
|
|
struct ipv6hdr _ipv6h, *ip6;
|
|
|
|
offset = skb_network_offset(skb);
|
|
ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
|
|
if (ip6 == NULL)
|
|
goto out;
|
|
|
|
ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
|
|
ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
|
|
ret = 0;
|
|
|
|
nexthdr = ip6->nexthdr;
|
|
offset += sizeof(_ipv6h);
|
|
offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
|
|
if (offset < 0)
|
|
goto out;
|
|
|
|
if (proto)
|
|
*proto = nexthdr;
|
|
|
|
switch (nexthdr) {
|
|
case IPPROTO_TCP: {
|
|
struct tcphdr _tcph, *th;
|
|
|
|
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
|
|
if (th == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = th->source;
|
|
ad->u.net.dport = th->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_UDP: {
|
|
struct udphdr _udph, *uh;
|
|
|
|
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
|
|
if (uh == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = uh->source;
|
|
ad->u.net.dport = uh->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_DCCP: {
|
|
struct dccp_hdr _dccph, *dh;
|
|
|
|
dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
|
|
if (dh == NULL)
|
|
break;
|
|
|
|
ad->u.net.sport = dh->dccph_sport;
|
|
ad->u.net.dport = dh->dccph_dport;
|
|
break;
|
|
}
|
|
|
|
/* includes fragments */
|
|
default:
|
|
break;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
#endif /* IPV6 */
|
|
|
|
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
|
|
char **_addrp, int src, u8 *proto)
|
|
{
|
|
char *addrp;
|
|
int ret;
|
|
|
|
switch (ad->u.net.family) {
|
|
case PF_INET:
|
|
ret = selinux_parse_skb_ipv4(skb, ad, proto);
|
|
if (ret)
|
|
goto parse_error;
|
|
addrp = (char *)(src ? &ad->u.net.v4info.saddr :
|
|
&ad->u.net.v4info.daddr);
|
|
goto okay;
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
case PF_INET6:
|
|
ret = selinux_parse_skb_ipv6(skb, ad, proto);
|
|
if (ret)
|
|
goto parse_error;
|
|
addrp = (char *)(src ? &ad->u.net.v6info.saddr :
|
|
&ad->u.net.v6info.daddr);
|
|
goto okay;
|
|
#endif /* IPV6 */
|
|
default:
|
|
addrp = NULL;
|
|
goto okay;
|
|
}
|
|
|
|
parse_error:
|
|
printk(KERN_WARNING
|
|
"SELinux: failure in selinux_parse_skb(),"
|
|
" unable to parse packet\n");
|
|
return ret;
|
|
|
|
okay:
|
|
if (_addrp)
|
|
*_addrp = addrp;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* selinux_skb_peerlbl_sid - Determine the peer label of a packet
|
|
* @skb: the packet
|
|
* @family: protocol family
|
|
* @sid: the packet's peer label SID
|
|
*
|
|
* Description:
|
|
* Check the various different forms of network peer labeling and determine
|
|
* the peer label/SID for the packet; most of the magic actually occurs in
|
|
* the security server function security_net_peersid_cmp(). The function
|
|
* returns zero if the value in @sid is valid (although it may be SECSID_NULL)
|
|
* or -EACCES if @sid is invalid due to inconsistencies with the different
|
|
* peer labels.
|
|
*
|
|
*/
|
|
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
|
|
{
|
|
int err;
|
|
u32 xfrm_sid;
|
|
u32 nlbl_sid;
|
|
u32 nlbl_type;
|
|
|
|
selinux_skb_xfrm_sid(skb, &xfrm_sid);
|
|
selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
|
|
|
|
err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
|
|
if (unlikely(err)) {
|
|
printk(KERN_WARNING
|
|
"SELinux: failure in selinux_skb_peerlbl_sid(),"
|
|
" unable to determine packet's peer label\n");
|
|
return -EACCES;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* socket security operations */
|
|
|
|
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
|
|
u16 secclass, u32 *socksid)
|
|
{
|
|
if (tsec->sockcreate_sid > SECSID_NULL) {
|
|
*socksid = tsec->sockcreate_sid;
|
|
return 0;
|
|
}
|
|
|
|
return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
|
|
socksid);
|
|
}
|
|
|
|
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct common_audit_data ad;
|
|
u32 tsid = task_sid(task);
|
|
|
|
if (sksec->sid == SECINITSID_KERNEL)
|
|
return 0;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.sk = sk;
|
|
|
|
return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
|
|
}
|
|
|
|
static int selinux_socket_create(int family, int type,
|
|
int protocol, int kern)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
u32 newsid;
|
|
u16 secclass;
|
|
int rc;
|
|
|
|
if (kern)
|
|
return 0;
|
|
|
|
secclass = socket_type_to_security_class(family, type, protocol);
|
|
rc = socket_sockcreate_sid(tsec, secclass, &newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
|
|
}
|
|
|
|
static int selinux_socket_post_create(struct socket *sock, int family,
|
|
int type, int protocol, int kern)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
|
|
struct sk_security_struct *sksec;
|
|
int err = 0;
|
|
|
|
isec->sclass = socket_type_to_security_class(family, type, protocol);
|
|
|
|
if (kern)
|
|
isec->sid = SECINITSID_KERNEL;
|
|
else {
|
|
err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
isec->initialized = 1;
|
|
|
|
if (sock->sk) {
|
|
sksec = sock->sk->sk_security;
|
|
sksec->sid = isec->sid;
|
|
sksec->sclass = isec->sclass;
|
|
err = selinux_netlbl_socket_post_create(sock->sk, family);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/* Range of port numbers used to automatically bind.
|
|
Need to determine whether we should perform a name_bind
|
|
permission check between the socket and the port number. */
|
|
|
|
static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
|
|
{
|
|
struct sock *sk = sock->sk;
|
|
u16 family;
|
|
int err;
|
|
|
|
err = sock_has_perm(current, sk, SOCKET__BIND);
|
|
if (err)
|
|
goto out;
|
|
|
|
/*
|
|
* If PF_INET or PF_INET6, check name_bind permission for the port.
|
|
* Multiple address binding for SCTP is not supported yet: we just
|
|
* check the first address now.
|
|
*/
|
|
family = sk->sk_family;
|
|
if (family == PF_INET || family == PF_INET6) {
|
|
char *addrp;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct common_audit_data ad;
|
|
struct sockaddr_in *addr4 = NULL;
|
|
struct sockaddr_in6 *addr6 = NULL;
|
|
unsigned short snum;
|
|
u32 sid, node_perm;
|
|
|
|
if (family == PF_INET) {
|
|
addr4 = (struct sockaddr_in *)address;
|
|
snum = ntohs(addr4->sin_port);
|
|
addrp = (char *)&addr4->sin_addr.s_addr;
|
|
} else {
|
|
addr6 = (struct sockaddr_in6 *)address;
|
|
snum = ntohs(addr6->sin6_port);
|
|
addrp = (char *)&addr6->sin6_addr.s6_addr;
|
|
}
|
|
|
|
if (snum) {
|
|
int low, high;
|
|
|
|
inet_get_local_port_range(&low, &high);
|
|
|
|
if (snum < max(PROT_SOCK, low) || snum > high) {
|
|
err = sel_netport_sid(sk->sk_protocol,
|
|
snum, &sid);
|
|
if (err)
|
|
goto out;
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.sport = htons(snum);
|
|
ad.u.net.family = family;
|
|
err = avc_has_perm(sksec->sid, sid,
|
|
sksec->sclass,
|
|
SOCKET__NAME_BIND, &ad);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
switch (sksec->sclass) {
|
|
case SECCLASS_TCP_SOCKET:
|
|
node_perm = TCP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
case SECCLASS_UDP_SOCKET:
|
|
node_perm = UDP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
case SECCLASS_DCCP_SOCKET:
|
|
node_perm = DCCP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
default:
|
|
node_perm = RAWIP_SOCKET__NODE_BIND;
|
|
break;
|
|
}
|
|
|
|
err = sel_netnode_sid(addrp, family, &sid);
|
|
if (err)
|
|
goto out;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.sport = htons(snum);
|
|
ad.u.net.family = family;
|
|
|
|
if (family == PF_INET)
|
|
ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
|
|
else
|
|
ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
|
|
|
|
err = avc_has_perm(sksec->sid, sid,
|
|
sksec->sclass, node_perm, &ad);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
|
|
{
|
|
struct sock *sk = sock->sk;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
int err;
|
|
|
|
err = sock_has_perm(current, sk, SOCKET__CONNECT);
|
|
if (err)
|
|
return err;
|
|
|
|
/*
|
|
* If a TCP or DCCP socket, check name_connect permission for the port.
|
|
*/
|
|
if (sksec->sclass == SECCLASS_TCP_SOCKET ||
|
|
sksec->sclass == SECCLASS_DCCP_SOCKET) {
|
|
struct common_audit_data ad;
|
|
struct sockaddr_in *addr4 = NULL;
|
|
struct sockaddr_in6 *addr6 = NULL;
|
|
unsigned short snum;
|
|
u32 sid, perm;
|
|
|
|
if (sk->sk_family == PF_INET) {
|
|
addr4 = (struct sockaddr_in *)address;
|
|
if (addrlen < sizeof(struct sockaddr_in))
|
|
return -EINVAL;
|
|
snum = ntohs(addr4->sin_port);
|
|
} else {
|
|
addr6 = (struct sockaddr_in6 *)address;
|
|
if (addrlen < SIN6_LEN_RFC2133)
|
|
return -EINVAL;
|
|
snum = ntohs(addr6->sin6_port);
|
|
}
|
|
|
|
err = sel_netport_sid(sk->sk_protocol, snum, &sid);
|
|
if (err)
|
|
goto out;
|
|
|
|
perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
|
|
TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.dport = htons(snum);
|
|
ad.u.net.family = sk->sk_family;
|
|
err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
err = selinux_netlbl_socket_connect(sk, address);
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_listen(struct socket *sock, int backlog)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
|
|
}
|
|
|
|
static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
|
|
{
|
|
int err;
|
|
struct inode_security_struct *isec;
|
|
struct inode_security_struct *newisec;
|
|
|
|
err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
|
|
if (err)
|
|
return err;
|
|
|
|
newisec = SOCK_INODE(newsock)->i_security;
|
|
|
|
isec = SOCK_INODE(sock)->i_security;
|
|
newisec->sclass = isec->sclass;
|
|
newisec->sid = isec->sid;
|
|
newisec->initialized = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
|
|
int size)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__WRITE);
|
|
}
|
|
|
|
static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
|
|
int size, int flags)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__READ);
|
|
}
|
|
|
|
static int selinux_socket_getsockname(struct socket *sock)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
|
|
}
|
|
|
|
static int selinux_socket_getpeername(struct socket *sock)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
|
|
}
|
|
|
|
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
|
|
{
|
|
int err;
|
|
|
|
err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
|
|
if (err)
|
|
return err;
|
|
|
|
return selinux_netlbl_socket_setsockopt(sock, level, optname);
|
|
}
|
|
|
|
static int selinux_socket_getsockopt(struct socket *sock, int level,
|
|
int optname)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
|
|
}
|
|
|
|
static int selinux_socket_shutdown(struct socket *sock, int how)
|
|
{
|
|
return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
|
|
}
|
|
|
|
static int selinux_socket_unix_stream_connect(struct sock *sock,
|
|
struct sock *other,
|
|
struct sock *newsk)
|
|
{
|
|
struct sk_security_struct *sksec_sock = sock->sk_security;
|
|
struct sk_security_struct *sksec_other = other->sk_security;
|
|
struct sk_security_struct *sksec_new = newsk->sk_security;
|
|
struct common_audit_data ad;
|
|
int err;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.sk = other;
|
|
|
|
err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
|
|
sksec_other->sclass,
|
|
UNIX_STREAM_SOCKET__CONNECTTO, &ad);
|
|
if (err)
|
|
return err;
|
|
|
|
/* server child socket */
|
|
sksec_new->peer_sid = sksec_sock->sid;
|
|
err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
|
|
&sksec_new->sid);
|
|
if (err)
|
|
return err;
|
|
|
|
/* connecting socket */
|
|
sksec_sock->peer_sid = sksec_new->sid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_socket_unix_may_send(struct socket *sock,
|
|
struct socket *other)
|
|
{
|
|
struct sk_security_struct *ssec = sock->sk->sk_security;
|
|
struct sk_security_struct *osec = other->sk->sk_security;
|
|
struct common_audit_data ad;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.sk = other->sk;
|
|
|
|
return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
|
|
&ad);
|
|
}
|
|
|
|
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
|
|
u32 peer_sid,
|
|
struct common_audit_data *ad)
|
|
{
|
|
int err;
|
|
u32 if_sid;
|
|
u32 node_sid;
|
|
|
|
err = sel_netif_sid(ifindex, &if_sid);
|
|
if (err)
|
|
return err;
|
|
err = avc_has_perm(peer_sid, if_sid,
|
|
SECCLASS_NETIF, NETIF__INGRESS, ad);
|
|
if (err)
|
|
return err;
|
|
|
|
err = sel_netnode_sid(addrp, family, &node_sid);
|
|
if (err)
|
|
return err;
|
|
return avc_has_perm(peer_sid, node_sid,
|
|
SECCLASS_NODE, NODE__RECVFROM, ad);
|
|
}
|
|
|
|
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
|
|
u16 family)
|
|
{
|
|
int err = 0;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u32 sk_sid = sksec->sid;
|
|
struct common_audit_data ad;
|
|
char *addrp;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.netif = skb->skb_iif;
|
|
ad.u.net.family = family;
|
|
err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
|
|
if (err)
|
|
return err;
|
|
|
|
if (selinux_secmark_enabled()) {
|
|
err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
|
|
PACKET__RECV, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
|
|
if (err)
|
|
return err;
|
|
err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u16 family = sk->sk_family;
|
|
u32 sk_sid = sksec->sid;
|
|
struct common_audit_data ad;
|
|
char *addrp;
|
|
u8 secmark_active;
|
|
u8 peerlbl_active;
|
|
|
|
if (family != PF_INET && family != PF_INET6)
|
|
return 0;
|
|
|
|
/* Handle mapped IPv4 packets arriving via IPv6 sockets */
|
|
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
|
|
/* If any sort of compatibility mode is enabled then handoff processing
|
|
* to the selinux_sock_rcv_skb_compat() function to deal with the
|
|
* special handling. We do this in an attempt to keep this function
|
|
* as fast and as clean as possible. */
|
|
if (!selinux_policycap_netpeer)
|
|
return selinux_sock_rcv_skb_compat(sk, skb, family);
|
|
|
|
secmark_active = selinux_secmark_enabled();
|
|
peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return 0;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.netif = skb->skb_iif;
|
|
ad.u.net.family = family;
|
|
err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
|
|
if (err)
|
|
return err;
|
|
|
|
if (peerlbl_active) {
|
|
u32 peer_sid;
|
|
|
|
err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
|
|
if (err)
|
|
return err;
|
|
err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
|
|
peer_sid, &ad);
|
|
if (err) {
|
|
selinux_netlbl_err(skb, err, 0);
|
|
return err;
|
|
}
|
|
err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
|
|
PEER__RECV, &ad);
|
|
if (err)
|
|
selinux_netlbl_err(skb, err, 0);
|
|
}
|
|
|
|
if (secmark_active) {
|
|
err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
|
|
PACKET__RECV, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
|
|
int __user *optlen, unsigned len)
|
|
{
|
|
int err = 0;
|
|
char *scontext;
|
|
u32 scontext_len;
|
|
struct sk_security_struct *sksec = sock->sk->sk_security;
|
|
u32 peer_sid = SECSID_NULL;
|
|
|
|
if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
|
|
sksec->sclass == SECCLASS_TCP_SOCKET)
|
|
peer_sid = sksec->peer_sid;
|
|
if (peer_sid == SECSID_NULL)
|
|
return -ENOPROTOOPT;
|
|
|
|
err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
|
|
if (err)
|
|
return err;
|
|
|
|
if (scontext_len > len) {
|
|
err = -ERANGE;
|
|
goto out_len;
|
|
}
|
|
|
|
if (copy_to_user(optval, scontext, scontext_len))
|
|
err = -EFAULT;
|
|
|
|
out_len:
|
|
if (put_user(scontext_len, optlen))
|
|
err = -EFAULT;
|
|
kfree(scontext);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
|
|
{
|
|
u32 peer_secid = SECSID_NULL;
|
|
u16 family;
|
|
|
|
if (skb && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
else if (skb && skb->protocol == htons(ETH_P_IPV6))
|
|
family = PF_INET6;
|
|
else if (sock)
|
|
family = sock->sk->sk_family;
|
|
else
|
|
goto out;
|
|
|
|
if (sock && family == PF_UNIX)
|
|
selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
|
|
else if (skb)
|
|
selinux_skb_peerlbl_sid(skb, family, &peer_secid);
|
|
|
|
out:
|
|
*secid = peer_secid;
|
|
if (peer_secid == SECSID_NULL)
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
|
|
{
|
|
struct sk_security_struct *sksec;
|
|
|
|
sksec = kzalloc(sizeof(*sksec), priority);
|
|
if (!sksec)
|
|
return -ENOMEM;
|
|
|
|
sksec->peer_sid = SECINITSID_UNLABELED;
|
|
sksec->sid = SECINITSID_UNLABELED;
|
|
selinux_netlbl_sk_security_reset(sksec);
|
|
sk->sk_security = sksec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_sk_free_security(struct sock *sk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
sk->sk_security = NULL;
|
|
selinux_netlbl_sk_security_free(sksec);
|
|
kfree(sksec);
|
|
}
|
|
|
|
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct sk_security_struct *newsksec = newsk->sk_security;
|
|
|
|
newsksec->sid = sksec->sid;
|
|
newsksec->peer_sid = sksec->peer_sid;
|
|
newsksec->sclass = sksec->sclass;
|
|
|
|
selinux_netlbl_sk_security_reset(newsksec);
|
|
}
|
|
|
|
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
|
|
{
|
|
if (!sk)
|
|
*secid = SECINITSID_ANY_SOCKET;
|
|
else {
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
*secid = sksec->sid;
|
|
}
|
|
}
|
|
|
|
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
|
|
{
|
|
struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
|
|
sk->sk_family == PF_UNIX)
|
|
isec->sid = sksec->sid;
|
|
sksec->sclass = isec->sclass;
|
|
}
|
|
|
|
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
|
|
struct request_sock *req)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
int err;
|
|
u16 family = sk->sk_family;
|
|
u32 newsid;
|
|
u32 peersid;
|
|
|
|
/* handle mapped IPv4 packets arriving via IPv6 sockets */
|
|
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
|
|
err = selinux_skb_peerlbl_sid(skb, family, &peersid);
|
|
if (err)
|
|
return err;
|
|
if (peersid == SECSID_NULL) {
|
|
req->secid = sksec->sid;
|
|
req->peer_secid = SECSID_NULL;
|
|
} else {
|
|
err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
|
|
if (err)
|
|
return err;
|
|
req->secid = newsid;
|
|
req->peer_secid = peersid;
|
|
}
|
|
|
|
return selinux_netlbl_inet_conn_request(req, family);
|
|
}
|
|
|
|
static void selinux_inet_csk_clone(struct sock *newsk,
|
|
const struct request_sock *req)
|
|
{
|
|
struct sk_security_struct *newsksec = newsk->sk_security;
|
|
|
|
newsksec->sid = req->secid;
|
|
newsksec->peer_sid = req->peer_secid;
|
|
/* NOTE: Ideally, we should also get the isec->sid for the
|
|
new socket in sync, but we don't have the isec available yet.
|
|
So we will wait until sock_graft to do it, by which
|
|
time it will have been created and available. */
|
|
|
|
/* We don't need to take any sort of lock here as we are the only
|
|
* thread with access to newsksec */
|
|
selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
|
|
}
|
|
|
|
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
u16 family = sk->sk_family;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
/* handle mapped IPv4 packets arriving via IPv6 sockets */
|
|
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
|
|
selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
|
|
}
|
|
|
|
static int selinux_secmark_relabel_packet(u32 sid)
|
|
{
|
|
const struct task_security_struct *__tsec;
|
|
u32 tsid;
|
|
|
|
__tsec = current_security();
|
|
tsid = __tsec->sid;
|
|
|
|
return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
|
|
}
|
|
|
|
static void selinux_secmark_refcount_inc(void)
|
|
{
|
|
atomic_inc(&selinux_secmark_refcount);
|
|
}
|
|
|
|
static void selinux_secmark_refcount_dec(void)
|
|
{
|
|
atomic_dec(&selinux_secmark_refcount);
|
|
}
|
|
|
|
static void selinux_req_classify_flow(const struct request_sock *req,
|
|
struct flowi *fl)
|
|
{
|
|
fl->flowi_secid = req->secid;
|
|
}
|
|
|
|
static int selinux_tun_dev_create(void)
|
|
{
|
|
u32 sid = current_sid();
|
|
|
|
/* we aren't taking into account the "sockcreate" SID since the socket
|
|
* that is being created here is not a socket in the traditional sense,
|
|
* instead it is a private sock, accessible only to the kernel, and
|
|
* representing a wide range of network traffic spanning multiple
|
|
* connections unlike traditional sockets - check the TUN driver to
|
|
* get a better understanding of why this socket is special */
|
|
|
|
return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
|
|
NULL);
|
|
}
|
|
|
|
static void selinux_tun_dev_post_create(struct sock *sk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
/* we don't currently perform any NetLabel based labeling here and it
|
|
* isn't clear that we would want to do so anyway; while we could apply
|
|
* labeling without the support of the TUN user the resulting labeled
|
|
* traffic from the other end of the connection would almost certainly
|
|
* cause confusion to the TUN user that had no idea network labeling
|
|
* protocols were being used */
|
|
|
|
/* see the comments in selinux_tun_dev_create() about why we don't use
|
|
* the sockcreate SID here */
|
|
|
|
sksec->sid = current_sid();
|
|
sksec->sclass = SECCLASS_TUN_SOCKET;
|
|
}
|
|
|
|
static int selinux_tun_dev_attach(struct sock *sk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u32 sid = current_sid();
|
|
int err;
|
|
|
|
err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
|
|
TUN_SOCKET__RELABELFROM, NULL);
|
|
if (err)
|
|
return err;
|
|
err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
|
|
TUN_SOCKET__RELABELTO, NULL);
|
|
if (err)
|
|
return err;
|
|
|
|
sksec->sid = sid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
int err = 0;
|
|
u32 perm;
|
|
struct nlmsghdr *nlh;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
if (skb->len < NLMSG_SPACE(0)) {
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
nlh = nlmsg_hdr(skb);
|
|
|
|
err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
|
|
if (err) {
|
|
if (err == -EINVAL) {
|
|
audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
|
|
"SELinux: unrecognized netlink message"
|
|
" type=%hu for sclass=%hu\n",
|
|
nlh->nlmsg_type, sksec->sclass);
|
|
if (!selinux_enforcing || security_get_allow_unknown())
|
|
err = 0;
|
|
}
|
|
|
|
/* Ignore */
|
|
if (err == -ENOENT)
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
|
|
err = sock_has_perm(current, sk, perm);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_NETFILTER
|
|
|
|
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
|
|
u16 family)
|
|
{
|
|
int err;
|
|
char *addrp;
|
|
u32 peer_sid;
|
|
struct common_audit_data ad;
|
|
u8 secmark_active;
|
|
u8 netlbl_active;
|
|
u8 peerlbl_active;
|
|
|
|
if (!selinux_policycap_netpeer)
|
|
return NF_ACCEPT;
|
|
|
|
secmark_active = selinux_secmark_enabled();
|
|
netlbl_active = netlbl_enabled();
|
|
peerlbl_active = netlbl_active || selinux_xfrm_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return NF_ACCEPT;
|
|
|
|
if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
|
|
return NF_DROP;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.netif = ifindex;
|
|
ad.u.net.family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
|
|
return NF_DROP;
|
|
|
|
if (peerlbl_active) {
|
|
err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
|
|
peer_sid, &ad);
|
|
if (err) {
|
|
selinux_netlbl_err(skb, err, 1);
|
|
return NF_DROP;
|
|
}
|
|
}
|
|
|
|
if (secmark_active)
|
|
if (avc_has_perm(peer_sid, skb->secmark,
|
|
SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
|
|
return NF_DROP;
|
|
|
|
if (netlbl_active)
|
|
/* we do this in the FORWARD path and not the POST_ROUTING
|
|
* path because we want to make sure we apply the necessary
|
|
* labeling before IPsec is applied so we can leverage AH
|
|
* protection */
|
|
if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
|
|
return NF_DROP;
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_forward(unsigned int hooknum,
|
|
struct sk_buff *skb,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
int (*okfn)(struct sk_buff *))
|
|
{
|
|
return selinux_ip_forward(skb, in->ifindex, PF_INET);
|
|
}
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
static unsigned int selinux_ipv6_forward(unsigned int hooknum,
|
|
struct sk_buff *skb,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
int (*okfn)(struct sk_buff *))
|
|
{
|
|
return selinux_ip_forward(skb, in->ifindex, PF_INET6);
|
|
}
|
|
#endif /* IPV6 */
|
|
|
|
static unsigned int selinux_ip_output(struct sk_buff *skb,
|
|
u16 family)
|
|
{
|
|
u32 sid;
|
|
|
|
if (!netlbl_enabled())
|
|
return NF_ACCEPT;
|
|
|
|
/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
|
|
* because we want to make sure we apply the necessary labeling
|
|
* before IPsec is applied so we can leverage AH protection */
|
|
if (skb->sk) {
|
|
struct sk_security_struct *sksec = skb->sk->sk_security;
|
|
sid = sksec->sid;
|
|
} else
|
|
sid = SECINITSID_KERNEL;
|
|
if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
|
|
return NF_DROP;
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_output(unsigned int hooknum,
|
|
struct sk_buff *skb,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
int (*okfn)(struct sk_buff *))
|
|
{
|
|
return selinux_ip_output(skb, PF_INET);
|
|
}
|
|
|
|
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
|
|
int ifindex,
|
|
u16 family)
|
|
{
|
|
struct sock *sk = skb->sk;
|
|
struct sk_security_struct *sksec;
|
|
struct common_audit_data ad;
|
|
char *addrp;
|
|
u8 proto;
|
|
|
|
if (sk == NULL)
|
|
return NF_ACCEPT;
|
|
sksec = sk->sk_security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.netif = ifindex;
|
|
ad.u.net.family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
|
|
return NF_DROP;
|
|
|
|
if (selinux_secmark_enabled())
|
|
if (avc_has_perm(sksec->sid, skb->secmark,
|
|
SECCLASS_PACKET, PACKET__SEND, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
|
|
u16 family)
|
|
{
|
|
u32 secmark_perm;
|
|
u32 peer_sid;
|
|
struct sock *sk;
|
|
struct common_audit_data ad;
|
|
char *addrp;
|
|
u8 secmark_active;
|
|
u8 peerlbl_active;
|
|
|
|
/* If any sort of compatibility mode is enabled then handoff processing
|
|
* to the selinux_ip_postroute_compat() function to deal with the
|
|
* special handling. We do this in an attempt to keep this function
|
|
* as fast and as clean as possible. */
|
|
if (!selinux_policycap_netpeer)
|
|
return selinux_ip_postroute_compat(skb, ifindex, family);
|
|
#ifdef CONFIG_XFRM
|
|
/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
|
|
* packet transformation so allow the packet to pass without any checks
|
|
* since we'll have another chance to perform access control checks
|
|
* when the packet is on it's final way out.
|
|
* NOTE: there appear to be some IPv6 multicast cases where skb->dst
|
|
* is NULL, in this case go ahead and apply access control. */
|
|
if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
|
|
return NF_ACCEPT;
|
|
#endif
|
|
secmark_active = selinux_secmark_enabled();
|
|
peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return NF_ACCEPT;
|
|
|
|
/* if the packet is being forwarded then get the peer label from the
|
|
* packet itself; otherwise check to see if it is from a local
|
|
* application or the kernel, if from an application get the peer label
|
|
* from the sending socket, otherwise use the kernel's sid */
|
|
sk = skb->sk;
|
|
if (sk == NULL) {
|
|
if (skb->skb_iif) {
|
|
secmark_perm = PACKET__FORWARD_OUT;
|
|
if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
|
|
return NF_DROP;
|
|
} else {
|
|
secmark_perm = PACKET__SEND;
|
|
peer_sid = SECINITSID_KERNEL;
|
|
}
|
|
} else {
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
peer_sid = sksec->sid;
|
|
secmark_perm = PACKET__SEND;
|
|
}
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, NET);
|
|
ad.u.net.netif = ifindex;
|
|
ad.u.net.family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
|
|
return NF_DROP;
|
|
|
|
if (secmark_active)
|
|
if (avc_has_perm(peer_sid, skb->secmark,
|
|
SECCLASS_PACKET, secmark_perm, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (peerlbl_active) {
|
|
u32 if_sid;
|
|
u32 node_sid;
|
|
|
|
if (sel_netif_sid(ifindex, &if_sid))
|
|
return NF_DROP;
|
|
if (avc_has_perm(peer_sid, if_sid,
|
|
SECCLASS_NETIF, NETIF__EGRESS, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (sel_netnode_sid(addrp, family, &node_sid))
|
|
return NF_DROP;
|
|
if (avc_has_perm(peer_sid, node_sid,
|
|
SECCLASS_NODE, NODE__SENDTO, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
}
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
|
|
struct sk_buff *skb,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
int (*okfn)(struct sk_buff *))
|
|
{
|
|
return selinux_ip_postroute(skb, out->ifindex, PF_INET);
|
|
}
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
|
|
struct sk_buff *skb,
|
|
const struct net_device *in,
|
|
const struct net_device *out,
|
|
int (*okfn)(struct sk_buff *))
|
|
{
|
|
return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
|
|
}
|
|
#endif /* IPV6 */
|
|
|
|
#endif /* CONFIG_NETFILTER */
|
|
|
|
static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
|
|
err = cap_netlink_send(sk, skb);
|
|
if (err)
|
|
return err;
|
|
|
|
return selinux_nlmsg_perm(sk, skb);
|
|
}
|
|
|
|
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
|
|
{
|
|
int err;
|
|
struct common_audit_data ad;
|
|
u32 sid;
|
|
|
|
err = cap_netlink_recv(skb, capability);
|
|
if (err)
|
|
return err;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, CAP);
|
|
ad.u.cap = capability;
|
|
|
|
security_task_getsecid(current, &sid);
|
|
return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
|
|
CAP_TO_MASK(capability), &ad);
|
|
}
|
|
|
|
static int ipc_alloc_security(struct task_struct *task,
|
|
struct kern_ipc_perm *perm,
|
|
u16 sclass)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
u32 sid;
|
|
|
|
isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
|
|
if (!isec)
|
|
return -ENOMEM;
|
|
|
|
sid = task_sid(task);
|
|
isec->sclass = sclass;
|
|
isec->sid = sid;
|
|
perm->security = isec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ipc_free_security(struct kern_ipc_perm *perm)
|
|
{
|
|
struct ipc_security_struct *isec = perm->security;
|
|
perm->security = NULL;
|
|
kfree(isec);
|
|
}
|
|
|
|
static int msg_msg_alloc_security(struct msg_msg *msg)
|
|
{
|
|
struct msg_security_struct *msec;
|
|
|
|
msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
|
|
if (!msec)
|
|
return -ENOMEM;
|
|
|
|
msec->sid = SECINITSID_UNLABELED;
|
|
msg->security = msec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void msg_msg_free_security(struct msg_msg *msg)
|
|
{
|
|
struct msg_security_struct *msec = msg->security;
|
|
|
|
msg->security = NULL;
|
|
kfree(msec);
|
|
}
|
|
|
|
static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
|
|
u32 perms)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = ipc_perms->security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = ipc_perms->key;
|
|
|
|
return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
|
|
}
|
|
|
|
static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
|
|
{
|
|
return msg_msg_alloc_security(msg);
|
|
}
|
|
|
|
static void selinux_msg_msg_free_security(struct msg_msg *msg)
|
|
{
|
|
msg_msg_free_security(msg);
|
|
}
|
|
|
|
/* message queue security operations */
|
|
static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = msq->q_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = msq->q_perm.key;
|
|
|
|
rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(&msq->q_perm);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_msg_queue_free_security(struct msg_queue *msq)
|
|
{
|
|
ipc_free_security(&msq->q_perm);
|
|
}
|
|
|
|
static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = msq->q_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = msq->q_perm.key;
|
|
|
|
return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__ASSOCIATE, &ad);
|
|
}
|
|
|
|
static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
|
|
{
|
|
int err;
|
|
int perms;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case MSG_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return task_has_system(current, SYSTEM__IPC_INFO);
|
|
case IPC_STAT:
|
|
case MSG_STAT:
|
|
perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
|
|
break;
|
|
case IPC_SET:
|
|
perms = MSGQ__SETATTR;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = MSGQ__DESTROY;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(&msq->q_perm, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct msg_security_struct *msec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
isec = msq->q_perm.security;
|
|
msec = msg->security;
|
|
|
|
/*
|
|
* First time through, need to assign label to the message
|
|
*/
|
|
if (msec->sid == SECINITSID_UNLABELED) {
|
|
/*
|
|
* Compute new sid based on current process and
|
|
* message queue this message will be stored in
|
|
*/
|
|
rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
|
|
NULL, &msec->sid);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = msq->q_perm.key;
|
|
|
|
/* Can this process write to the queue? */
|
|
rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__WRITE, &ad);
|
|
if (!rc)
|
|
/* Can this process send the message */
|
|
rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
|
|
MSG__SEND, &ad);
|
|
if (!rc)
|
|
/* Can the message be put in the queue? */
|
|
rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__ENQUEUE, &ad);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
|
|
struct task_struct *target,
|
|
long type, int mode)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct msg_security_struct *msec;
|
|
struct common_audit_data ad;
|
|
u32 sid = task_sid(target);
|
|
int rc;
|
|
|
|
isec = msq->q_perm.security;
|
|
msec = msg->security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = msq->q_perm.key;
|
|
|
|
rc = avc_has_perm(sid, isec->sid,
|
|
SECCLASS_MSGQ, MSGQ__READ, &ad);
|
|
if (!rc)
|
|
rc = avc_has_perm(sid, msec->sid,
|
|
SECCLASS_MSG, MSG__RECEIVE, &ad);
|
|
return rc;
|
|
}
|
|
|
|
/* Shared Memory security operations */
|
|
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = shp->shm_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = shp->shm_perm.key;
|
|
|
|
rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
|
|
SHM__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(&shp->shm_perm);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_shm_free_security(struct shmid_kernel *shp)
|
|
{
|
|
ipc_free_security(&shp->shm_perm);
|
|
}
|
|
|
|
static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = shp->shm_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = shp->shm_perm.key;
|
|
|
|
return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
|
|
SHM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
/* Note, at this point, shp is locked down */
|
|
static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
|
|
{
|
|
int perms;
|
|
int err;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case SHM_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return task_has_system(current, SYSTEM__IPC_INFO);
|
|
case IPC_STAT:
|
|
case SHM_STAT:
|
|
perms = SHM__GETATTR | SHM__ASSOCIATE;
|
|
break;
|
|
case IPC_SET:
|
|
perms = SHM__SETATTR;
|
|
break;
|
|
case SHM_LOCK:
|
|
case SHM_UNLOCK:
|
|
perms = SHM__LOCK;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = SHM__DESTROY;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(&shp->shm_perm, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_shm_shmat(struct shmid_kernel *shp,
|
|
char __user *shmaddr, int shmflg)
|
|
{
|
|
u32 perms;
|
|
|
|
if (shmflg & SHM_RDONLY)
|
|
perms = SHM__READ;
|
|
else
|
|
perms = SHM__READ | SHM__WRITE;
|
|
|
|
return ipc_has_perm(&shp->shm_perm, perms);
|
|
}
|
|
|
|
/* Semaphore security operations */
|
|
static int selinux_sem_alloc_security(struct sem_array *sma)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = sma->sem_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = sma->sem_perm.key;
|
|
|
|
rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
|
|
SEM__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(&sma->sem_perm);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_sem_free_security(struct sem_array *sma)
|
|
{
|
|
ipc_free_security(&sma->sem_perm);
|
|
}
|
|
|
|
static int selinux_sem_associate(struct sem_array *sma, int semflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = sma->sem_perm.security;
|
|
|
|
COMMON_AUDIT_DATA_INIT(&ad, IPC);
|
|
ad.u.ipc_id = sma->sem_perm.key;
|
|
|
|
return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
|
|
SEM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
/* Note, at this point, sma is locked down */
|
|
static int selinux_sem_semctl(struct sem_array *sma, int cmd)
|
|
{
|
|
int err;
|
|
u32 perms;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case SEM_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return task_has_system(current, SYSTEM__IPC_INFO);
|
|
case GETPID:
|
|
case GETNCNT:
|
|
case GETZCNT:
|
|
perms = SEM__GETATTR;
|
|
break;
|
|
case GETVAL:
|
|
case GETALL:
|
|
perms = SEM__READ;
|
|
break;
|
|
case SETVAL:
|
|
case SETALL:
|
|
perms = SEM__WRITE;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = SEM__DESTROY;
|
|
break;
|
|
case IPC_SET:
|
|
perms = SEM__SETATTR;
|
|
break;
|
|
case IPC_STAT:
|
|
case SEM_STAT:
|
|
perms = SEM__GETATTR | SEM__ASSOCIATE;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(&sma->sem_perm, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_sem_semop(struct sem_array *sma,
|
|
struct sembuf *sops, unsigned nsops, int alter)
|
|
{
|
|
u32 perms;
|
|
|
|
if (alter)
|
|
perms = SEM__READ | SEM__WRITE;
|
|
else
|
|
perms = SEM__READ;
|
|
|
|
return ipc_has_perm(&sma->sem_perm, perms);
|
|
}
|
|
|
|
static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
|
|
{
|
|
u32 av = 0;
|
|
|
|
av = 0;
|
|
if (flag & S_IRUGO)
|
|
av |= IPC__UNIX_READ;
|
|
if (flag & S_IWUGO)
|
|
av |= IPC__UNIX_WRITE;
|
|
|
|
if (av == 0)
|
|
return 0;
|
|
|
|
return ipc_has_perm(ipcp, av);
|
|
}
|
|
|
|
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
|
|
{
|
|
struct ipc_security_struct *isec = ipcp->security;
|
|
*secid = isec->sid;
|
|
}
|
|
|
|
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
|
|
{
|
|
if (inode)
|
|
inode_doinit_with_dentry(inode, dentry);
|
|
}
|
|
|
|
static int selinux_getprocattr(struct task_struct *p,
|
|
char *name, char **value)
|
|
{
|
|
const struct task_security_struct *__tsec;
|
|
u32 sid;
|
|
int error;
|
|
unsigned len;
|
|
|
|
if (current != p) {
|
|
error = current_has_perm(p, PROCESS__GETATTR);
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
__tsec = __task_cred(p)->security;
|
|
|
|
if (!strcmp(name, "current"))
|
|
sid = __tsec->sid;
|
|
else if (!strcmp(name, "prev"))
|
|
sid = __tsec->osid;
|
|
else if (!strcmp(name, "exec"))
|
|
sid = __tsec->exec_sid;
|
|
else if (!strcmp(name, "fscreate"))
|
|
sid = __tsec->create_sid;
|
|
else if (!strcmp(name, "keycreate"))
|
|
sid = __tsec->keycreate_sid;
|
|
else if (!strcmp(name, "sockcreate"))
|
|
sid = __tsec->sockcreate_sid;
|
|
else
|
|
goto invalid;
|
|
rcu_read_unlock();
|
|
|
|
if (!sid)
|
|
return 0;
|
|
|
|
error = security_sid_to_context(sid, value, &len);
|
|
if (error)
|
|
return error;
|
|
return len;
|
|
|
|
invalid:
|
|
rcu_read_unlock();
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int selinux_setprocattr(struct task_struct *p,
|
|
char *name, void *value, size_t size)
|
|
{
|
|
struct task_security_struct *tsec;
|
|
struct task_struct *tracer;
|
|
struct cred *new;
|
|
u32 sid = 0, ptsid;
|
|
int error;
|
|
char *str = value;
|
|
|
|
if (current != p) {
|
|
/* SELinux only allows a process to change its own
|
|
security attributes. */
|
|
return -EACCES;
|
|
}
|
|
|
|
/*
|
|
* Basic control over ability to set these attributes at all.
|
|
* current == p, but we'll pass them separately in case the
|
|
* above restriction is ever removed.
|
|
*/
|
|
if (!strcmp(name, "exec"))
|
|
error = current_has_perm(p, PROCESS__SETEXEC);
|
|
else if (!strcmp(name, "fscreate"))
|
|
error = current_has_perm(p, PROCESS__SETFSCREATE);
|
|
else if (!strcmp(name, "keycreate"))
|
|
error = current_has_perm(p, PROCESS__SETKEYCREATE);
|
|
else if (!strcmp(name, "sockcreate"))
|
|
error = current_has_perm(p, PROCESS__SETSOCKCREATE);
|
|
else if (!strcmp(name, "current"))
|
|
error = current_has_perm(p, PROCESS__SETCURRENT);
|
|
else
|
|
error = -EINVAL;
|
|
if (error)
|
|
return error;
|
|
|
|
/* Obtain a SID for the context, if one was specified. */
|
|
if (size && str[1] && str[1] != '\n') {
|
|
if (str[size-1] == '\n') {
|
|
str[size-1] = 0;
|
|
size--;
|
|
}
|
|
error = security_context_to_sid(value, size, &sid);
|
|
if (error == -EINVAL && !strcmp(name, "fscreate")) {
|
|
if (!capable(CAP_MAC_ADMIN))
|
|
return error;
|
|
error = security_context_to_sid_force(value, size,
|
|
&sid);
|
|
}
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
new = prepare_creds();
|
|
if (!new)
|
|
return -ENOMEM;
|
|
|
|
/* Permission checking based on the specified context is
|
|
performed during the actual operation (execve,
|
|
open/mkdir/...), when we know the full context of the
|
|
operation. See selinux_bprm_set_creds for the execve
|
|
checks and may_create for the file creation checks. The
|
|
operation will then fail if the context is not permitted. */
|
|
tsec = new->security;
|
|
if (!strcmp(name, "exec")) {
|
|
tsec->exec_sid = sid;
|
|
} else if (!strcmp(name, "fscreate")) {
|
|
tsec->create_sid = sid;
|
|
} else if (!strcmp(name, "keycreate")) {
|
|
error = may_create_key(sid, p);
|
|
if (error)
|
|
goto abort_change;
|
|
tsec->keycreate_sid = sid;
|
|
} else if (!strcmp(name, "sockcreate")) {
|
|
tsec->sockcreate_sid = sid;
|
|
} else if (!strcmp(name, "current")) {
|
|
error = -EINVAL;
|
|
if (sid == 0)
|
|
goto abort_change;
|
|
|
|
/* Only allow single threaded processes to change context */
|
|
error = -EPERM;
|
|
if (!current_is_single_threaded()) {
|
|
error = security_bounded_transition(tsec->sid, sid);
|
|
if (error)
|
|
goto abort_change;
|
|
}
|
|
|
|
/* Check permissions for the transition. */
|
|
error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
|
|
PROCESS__DYNTRANSITION, NULL);
|
|
if (error)
|
|
goto abort_change;
|
|
|
|
/* Check for ptracing, and update the task SID if ok.
|
|
Otherwise, leave SID unchanged and fail. */
|
|
ptsid = 0;
|
|
task_lock(p);
|
|
tracer = tracehook_tracer_task(p);
|
|
if (tracer)
|
|
ptsid = task_sid(tracer);
|
|
task_unlock(p);
|
|
|
|
if (tracer) {
|
|
error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
|
|
PROCESS__PTRACE, NULL);
|
|
if (error)
|
|
goto abort_change;
|
|
}
|
|
|
|
tsec->sid = sid;
|
|
} else {
|
|
error = -EINVAL;
|
|
goto abort_change;
|
|
}
|
|
|
|
commit_creds(new);
|
|
return size;
|
|
|
|
abort_change:
|
|
abort_creds(new);
|
|
return error;
|
|
}
|
|
|
|
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
|
|
{
|
|
return security_sid_to_context(secid, secdata, seclen);
|
|
}
|
|
|
|
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
|
|
{
|
|
return security_context_to_sid(secdata, seclen, secid);
|
|
}
|
|
|
|
static void selinux_release_secctx(char *secdata, u32 seclen)
|
|
{
|
|
kfree(secdata);
|
|
}
|
|
|
|
/*
|
|
* called with inode->i_mutex locked
|
|
*/
|
|
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
|
|
{
|
|
return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
|
|
}
|
|
|
|
/*
|
|
* called with inode->i_mutex locked
|
|
*/
|
|
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
|
|
{
|
|
return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
|
|
}
|
|
|
|
static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
|
|
{
|
|
int len = 0;
|
|
len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
|
|
ctx, true);
|
|
if (len < 0)
|
|
return len;
|
|
*ctxlen = len;
|
|
return 0;
|
|
}
|
|
#ifdef CONFIG_KEYS
|
|
|
|
static int selinux_key_alloc(struct key *k, const struct cred *cred,
|
|
unsigned long flags)
|
|
{
|
|
const struct task_security_struct *tsec;
|
|
struct key_security_struct *ksec;
|
|
|
|
ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
|
|
if (!ksec)
|
|
return -ENOMEM;
|
|
|
|
tsec = cred->security;
|
|
if (tsec->keycreate_sid)
|
|
ksec->sid = tsec->keycreate_sid;
|
|
else
|
|
ksec->sid = tsec->sid;
|
|
|
|
k->security = ksec;
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_key_free(struct key *k)
|
|
{
|
|
struct key_security_struct *ksec = k->security;
|
|
|
|
k->security = NULL;
|
|
kfree(ksec);
|
|
}
|
|
|
|
static int selinux_key_permission(key_ref_t key_ref,
|
|
const struct cred *cred,
|
|
key_perm_t perm)
|
|
{
|
|
struct key *key;
|
|
struct key_security_struct *ksec;
|
|
u32 sid;
|
|
|
|
/* if no specific permissions are requested, we skip the
|
|
permission check. No serious, additional covert channels
|
|
appear to be created. */
|
|
if (perm == 0)
|
|
return 0;
|
|
|
|
sid = cred_sid(cred);
|
|
|
|
key = key_ref_to_ptr(key_ref);
|
|
ksec = key->security;
|
|
|
|
return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
|
|
}
|
|
|
|
static int selinux_key_getsecurity(struct key *key, char **_buffer)
|
|
{
|
|
struct key_security_struct *ksec = key->security;
|
|
char *context = NULL;
|
|
unsigned len;
|
|
int rc;
|
|
|
|
rc = security_sid_to_context(ksec->sid, &context, &len);
|
|
if (!rc)
|
|
rc = len;
|
|
*_buffer = context;
|
|
return rc;
|
|
}
|
|
|
|
#endif
|
|
|
|
static struct security_operations selinux_ops = {
|
|
.name = "selinux",
|
|
|
|
.ptrace_access_check = selinux_ptrace_access_check,
|
|
.ptrace_traceme = selinux_ptrace_traceme,
|
|
.capget = selinux_capget,
|
|
.capset = selinux_capset,
|
|
.capable = selinux_capable,
|
|
.quotactl = selinux_quotactl,
|
|
.quota_on = selinux_quota_on,
|
|
.syslog = selinux_syslog,
|
|
.vm_enough_memory = selinux_vm_enough_memory,
|
|
|
|
.netlink_send = selinux_netlink_send,
|
|
.netlink_recv = selinux_netlink_recv,
|
|
|
|
.bprm_set_creds = selinux_bprm_set_creds,
|
|
.bprm_committing_creds = selinux_bprm_committing_creds,
|
|
.bprm_committed_creds = selinux_bprm_committed_creds,
|
|
.bprm_secureexec = selinux_bprm_secureexec,
|
|
|
|
.sb_alloc_security = selinux_sb_alloc_security,
|
|
.sb_free_security = selinux_sb_free_security,
|
|
.sb_copy_data = selinux_sb_copy_data,
|
|
.sb_remount = selinux_sb_remount,
|
|
.sb_kern_mount = selinux_sb_kern_mount,
|
|
.sb_show_options = selinux_sb_show_options,
|
|
.sb_statfs = selinux_sb_statfs,
|
|
.sb_mount = selinux_mount,
|
|
.sb_umount = selinux_umount,
|
|
.sb_set_mnt_opts = selinux_set_mnt_opts,
|
|
.sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
|
|
.sb_parse_opts_str = selinux_parse_opts_str,
|
|
|
|
|
|
.inode_alloc_security = selinux_inode_alloc_security,
|
|
.inode_free_security = selinux_inode_free_security,
|
|
.inode_init_security = selinux_inode_init_security,
|
|
.inode_create = selinux_inode_create,
|
|
.inode_link = selinux_inode_link,
|
|
.inode_unlink = selinux_inode_unlink,
|
|
.inode_symlink = selinux_inode_symlink,
|
|
.inode_mkdir = selinux_inode_mkdir,
|
|
.inode_rmdir = selinux_inode_rmdir,
|
|
.inode_mknod = selinux_inode_mknod,
|
|
.inode_rename = selinux_inode_rename,
|
|
.inode_readlink = selinux_inode_readlink,
|
|
.inode_follow_link = selinux_inode_follow_link,
|
|
.inode_permission = selinux_inode_permission,
|
|
.inode_setattr = selinux_inode_setattr,
|
|
.inode_getattr = selinux_inode_getattr,
|
|
.inode_setxattr = selinux_inode_setxattr,
|
|
.inode_post_setxattr = selinux_inode_post_setxattr,
|
|
.inode_getxattr = selinux_inode_getxattr,
|
|
.inode_listxattr = selinux_inode_listxattr,
|
|
.inode_removexattr = selinux_inode_removexattr,
|
|
.inode_getsecurity = selinux_inode_getsecurity,
|
|
.inode_setsecurity = selinux_inode_setsecurity,
|
|
.inode_listsecurity = selinux_inode_listsecurity,
|
|
.inode_getsecid = selinux_inode_getsecid,
|
|
|
|
.file_permission = selinux_file_permission,
|
|
.file_alloc_security = selinux_file_alloc_security,
|
|
.file_free_security = selinux_file_free_security,
|
|
.file_ioctl = selinux_file_ioctl,
|
|
.file_mmap = selinux_file_mmap,
|
|
.file_mprotect = selinux_file_mprotect,
|
|
.file_lock = selinux_file_lock,
|
|
.file_fcntl = selinux_file_fcntl,
|
|
.file_set_fowner = selinux_file_set_fowner,
|
|
.file_send_sigiotask = selinux_file_send_sigiotask,
|
|
.file_receive = selinux_file_receive,
|
|
|
|
.dentry_open = selinux_dentry_open,
|
|
|
|
.task_create = selinux_task_create,
|
|
.cred_alloc_blank = selinux_cred_alloc_blank,
|
|
.cred_free = selinux_cred_free,
|
|
.cred_prepare = selinux_cred_prepare,
|
|
.cred_transfer = selinux_cred_transfer,
|
|
.kernel_act_as = selinux_kernel_act_as,
|
|
.kernel_create_files_as = selinux_kernel_create_files_as,
|
|
.kernel_module_request = selinux_kernel_module_request,
|
|
.task_setpgid = selinux_task_setpgid,
|
|
.task_getpgid = selinux_task_getpgid,
|
|
.task_getsid = selinux_task_getsid,
|
|
.task_getsecid = selinux_task_getsecid,
|
|
.task_setnice = selinux_task_setnice,
|
|
.task_setioprio = selinux_task_setioprio,
|
|
.task_getioprio = selinux_task_getioprio,
|
|
.task_setrlimit = selinux_task_setrlimit,
|
|
.task_setscheduler = selinux_task_setscheduler,
|
|
.task_getscheduler = selinux_task_getscheduler,
|
|
.task_movememory = selinux_task_movememory,
|
|
.task_kill = selinux_task_kill,
|
|
.task_wait = selinux_task_wait,
|
|
.task_to_inode = selinux_task_to_inode,
|
|
|
|
.ipc_permission = selinux_ipc_permission,
|
|
.ipc_getsecid = selinux_ipc_getsecid,
|
|
|
|
.msg_msg_alloc_security = selinux_msg_msg_alloc_security,
|
|
.msg_msg_free_security = selinux_msg_msg_free_security,
|
|
|
|
.msg_queue_alloc_security = selinux_msg_queue_alloc_security,
|
|
.msg_queue_free_security = selinux_msg_queue_free_security,
|
|
.msg_queue_associate = selinux_msg_queue_associate,
|
|
.msg_queue_msgctl = selinux_msg_queue_msgctl,
|
|
.msg_queue_msgsnd = selinux_msg_queue_msgsnd,
|
|
.msg_queue_msgrcv = selinux_msg_queue_msgrcv,
|
|
|
|
.shm_alloc_security = selinux_shm_alloc_security,
|
|
.shm_free_security = selinux_shm_free_security,
|
|
.shm_associate = selinux_shm_associate,
|
|
.shm_shmctl = selinux_shm_shmctl,
|
|
.shm_shmat = selinux_shm_shmat,
|
|
|
|
.sem_alloc_security = selinux_sem_alloc_security,
|
|
.sem_free_security = selinux_sem_free_security,
|
|
.sem_associate = selinux_sem_associate,
|
|
.sem_semctl = selinux_sem_semctl,
|
|
.sem_semop = selinux_sem_semop,
|
|
|
|
.d_instantiate = selinux_d_instantiate,
|
|
|
|
.getprocattr = selinux_getprocattr,
|
|
.setprocattr = selinux_setprocattr,
|
|
|
|
.secid_to_secctx = selinux_secid_to_secctx,
|
|
.secctx_to_secid = selinux_secctx_to_secid,
|
|
.release_secctx = selinux_release_secctx,
|
|
.inode_notifysecctx = selinux_inode_notifysecctx,
|
|
.inode_setsecctx = selinux_inode_setsecctx,
|
|
.inode_getsecctx = selinux_inode_getsecctx,
|
|
|
|
.unix_stream_connect = selinux_socket_unix_stream_connect,
|
|
.unix_may_send = selinux_socket_unix_may_send,
|
|
|
|
.socket_create = selinux_socket_create,
|
|
.socket_post_create = selinux_socket_post_create,
|
|
.socket_bind = selinux_socket_bind,
|
|
.socket_connect = selinux_socket_connect,
|
|
.socket_listen = selinux_socket_listen,
|
|
.socket_accept = selinux_socket_accept,
|
|
.socket_sendmsg = selinux_socket_sendmsg,
|
|
.socket_recvmsg = selinux_socket_recvmsg,
|
|
.socket_getsockname = selinux_socket_getsockname,
|
|
.socket_getpeername = selinux_socket_getpeername,
|
|
.socket_getsockopt = selinux_socket_getsockopt,
|
|
.socket_setsockopt = selinux_socket_setsockopt,
|
|
.socket_shutdown = selinux_socket_shutdown,
|
|
.socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
|
|
.socket_getpeersec_stream = selinux_socket_getpeersec_stream,
|
|
.socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
|
|
.sk_alloc_security = selinux_sk_alloc_security,
|
|
.sk_free_security = selinux_sk_free_security,
|
|
.sk_clone_security = selinux_sk_clone_security,
|
|
.sk_getsecid = selinux_sk_getsecid,
|
|
.sock_graft = selinux_sock_graft,
|
|
.inet_conn_request = selinux_inet_conn_request,
|
|
.inet_csk_clone = selinux_inet_csk_clone,
|
|
.inet_conn_established = selinux_inet_conn_established,
|
|
.secmark_relabel_packet = selinux_secmark_relabel_packet,
|
|
.secmark_refcount_inc = selinux_secmark_refcount_inc,
|
|
.secmark_refcount_dec = selinux_secmark_refcount_dec,
|
|
.req_classify_flow = selinux_req_classify_flow,
|
|
.tun_dev_create = selinux_tun_dev_create,
|
|
.tun_dev_post_create = selinux_tun_dev_post_create,
|
|
.tun_dev_attach = selinux_tun_dev_attach,
|
|
|
|
#ifdef CONFIG_SECURITY_NETWORK_XFRM
|
|
.xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
|
|
.xfrm_policy_clone_security = selinux_xfrm_policy_clone,
|
|
.xfrm_policy_free_security = selinux_xfrm_policy_free,
|
|
.xfrm_policy_delete_security = selinux_xfrm_policy_delete,
|
|
.xfrm_state_alloc_security = selinux_xfrm_state_alloc,
|
|
.xfrm_state_free_security = selinux_xfrm_state_free,
|
|
.xfrm_state_delete_security = selinux_xfrm_state_delete,
|
|
.xfrm_policy_lookup = selinux_xfrm_policy_lookup,
|
|
.xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
|
|
.xfrm_decode_session = selinux_xfrm_decode_session,
|
|
#endif
|
|
|
|
#ifdef CONFIG_KEYS
|
|
.key_alloc = selinux_key_alloc,
|
|
.key_free = selinux_key_free,
|
|
.key_permission = selinux_key_permission,
|
|
.key_getsecurity = selinux_key_getsecurity,
|
|
#endif
|
|
|
|
#ifdef CONFIG_AUDIT
|
|
.audit_rule_init = selinux_audit_rule_init,
|
|
.audit_rule_known = selinux_audit_rule_known,
|
|
.audit_rule_match = selinux_audit_rule_match,
|
|
.audit_rule_free = selinux_audit_rule_free,
|
|
#endif
|
|
};
|
|
|
|
static __init int selinux_init(void)
|
|
{
|
|
if (!security_module_enable(&selinux_ops)) {
|
|
selinux_enabled = 0;
|
|
return 0;
|
|
}
|
|
|
|
if (!selinux_enabled) {
|
|
printk(KERN_INFO "SELinux: Disabled at boot.\n");
|
|
return 0;
|
|
}
|
|
|
|
printk(KERN_INFO "SELinux: Initializing.\n");
|
|
|
|
/* Set the security state for the initial task. */
|
|
cred_init_security();
|
|
|
|
default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
|
|
|
|
sel_inode_cache = kmem_cache_create("selinux_inode_security",
|
|
sizeof(struct inode_security_struct),
|
|
0, SLAB_PANIC, NULL);
|
|
avc_init();
|
|
|
|
if (register_security(&selinux_ops))
|
|
panic("SELinux: Unable to register with kernel.\n");
|
|
|
|
if (selinux_enforcing)
|
|
printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
|
|
else
|
|
printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void delayed_superblock_init(struct super_block *sb, void *unused)
|
|
{
|
|
superblock_doinit(sb, NULL);
|
|
}
|
|
|
|
void selinux_complete_init(void)
|
|
{
|
|
printk(KERN_DEBUG "SELinux: Completing initialization.\n");
|
|
|
|
/* Set up any superblocks initialized prior to the policy load. */
|
|
printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
|
|
iterate_supers(delayed_superblock_init, NULL);
|
|
}
|
|
|
|
/* SELinux requires early initialization in order to label
|
|
all processes and objects when they are created. */
|
|
security_initcall(selinux_init);
|
|
|
|
#if defined(CONFIG_NETFILTER)
|
|
|
|
static struct nf_hook_ops selinux_ipv4_ops[] = {
|
|
{
|
|
.hook = selinux_ipv4_postroute,
|
|
.owner = THIS_MODULE,
|
|
.pf = PF_INET,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP_PRI_SELINUX_LAST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv4_forward,
|
|
.owner = THIS_MODULE,
|
|
.pf = PF_INET,
|
|
.hooknum = NF_INET_FORWARD,
|
|
.priority = NF_IP_PRI_SELINUX_FIRST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv4_output,
|
|
.owner = THIS_MODULE,
|
|
.pf = PF_INET,
|
|
.hooknum = NF_INET_LOCAL_OUT,
|
|
.priority = NF_IP_PRI_SELINUX_FIRST,
|
|
}
|
|
};
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
|
|
static struct nf_hook_ops selinux_ipv6_ops[] = {
|
|
{
|
|
.hook = selinux_ipv6_postroute,
|
|
.owner = THIS_MODULE,
|
|
.pf = PF_INET6,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP6_PRI_SELINUX_LAST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv6_forward,
|
|
.owner = THIS_MODULE,
|
|
.pf = PF_INET6,
|
|
.hooknum = NF_INET_FORWARD,
|
|
.priority = NF_IP6_PRI_SELINUX_FIRST,
|
|
}
|
|
};
|
|
|
|
#endif /* IPV6 */
|
|
|
|
static int __init selinux_nf_ip_init(void)
|
|
{
|
|
int err = 0;
|
|
|
|
if (!selinux_enabled)
|
|
goto out;
|
|
|
|
printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
|
|
|
|
err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
|
|
if (err)
|
|
panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
|
|
if (err)
|
|
panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
|
|
#endif /* IPV6 */
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
__initcall(selinux_nf_ip_init);
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
static void selinux_nf_ip_exit(void)
|
|
{
|
|
printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
|
|
|
|
nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
|
|
#endif /* IPV6 */
|
|
}
|
|
#endif
|
|
|
|
#else /* CONFIG_NETFILTER */
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
#define selinux_nf_ip_exit()
|
|
#endif
|
|
|
|
#endif /* CONFIG_NETFILTER */
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
static int selinux_disabled;
|
|
|
|
int selinux_disable(void)
|
|
{
|
|
extern void exit_sel_fs(void);
|
|
|
|
if (ss_initialized) {
|
|
/* Not permitted after initial policy load. */
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (selinux_disabled) {
|
|
/* Only do this once. */
|
|
return -EINVAL;
|
|
}
|
|
|
|
printk(KERN_INFO "SELinux: Disabled at runtime.\n");
|
|
|
|
selinux_disabled = 1;
|
|
selinux_enabled = 0;
|
|
|
|
reset_security_ops();
|
|
|
|
/* Try to destroy the avc node cache */
|
|
avc_disable();
|
|
|
|
/* Unregister netfilter hooks. */
|
|
selinux_nf_ip_exit();
|
|
|
|
/* Unregister selinuxfs. */
|
|
exit_sel_fs();
|
|
|
|
return 0;
|
|
}
|
|
#endif
|