linux/security/selinux/ss/policydb.h

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/*
* A policy database (policydb) specifies the
* configuration data for the security policy.
*
* Author : Stephen Smalley, <sds@epoch.ncsc.mil>
*/
/*
* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
* Support for enhanced MLS infrastructure.
*
* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
* Copyright (C) 2003 - 2004 Tresys Technology, LLC
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*/
#ifndef _SS_POLICYDB_H_
#define _SS_POLICYDB_H_
#include <linux/flex_array.h>
#include "symtab.h"
#include "avtab.h"
#include "sidtab.h"
#include "ebitmap.h"
#include "mls_types.h"
#include "context.h"
#include "constraint.h"
/*
* A datum type is defined for each kind of symbol
* in the configuration data: individual permissions,
* common prefixes for access vectors, classes,
* users, roles, types, sensitivities, categories, etc.
*/
/* Permission attributes */
struct perm_datum {
u32 value; /* permission bit + 1 */
};
/* Attributes of a common prefix for access vectors */
struct common_datum {
u32 value; /* internal common value */
struct symtab permissions; /* common permissions */
};
/* Class attributes */
struct class_datum {
u32 value; /* class value */
char *comkey; /* common name */
struct common_datum *comdatum; /* common datum */
struct symtab permissions; /* class-specific permission symbol table */
struct constraint_node *constraints; /* constraints on class permissions */
struct constraint_node *validatetrans; /* special transition rules */
};
/* Role attributes */
struct role_datum {
u32 value; /* internal role value */
SELinux: add boundary support and thread context assignment The purpose of this patch is to assign per-thread security context under a constraint. It enables multi-threaded server application to kick a request handler with its fair security context, and helps some of userspace object managers to handle user's request. When we assign a per-thread security context, it must not have wider permissions than the original one. Because a multi-threaded process shares a single local memory, an arbitary per-thread security context also means another thread can easily refer violated information. The constraint on a per-thread security context requires a new domain has to be equal or weaker than its original one, when it tries to assign a per-thread security context. Bounds relationship between two types is a way to ensure a domain can never have wider permission than its bounds. We can define it in two explicit or implicit ways. The first way is using new TYPEBOUNDS statement. It enables to define a boundary of types explicitly. The other one expand the concept of existing named based hierarchy. If we defines a type with "." separated name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t". This feature requires a new policy version. The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into kernel space, and the following patch enables to handle it. Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-08-28 09:35:57 +02:00
u32 bounds; /* boundary of role */
struct ebitmap dominates; /* set of roles dominated by this role */
struct ebitmap types; /* set of authorized types for role */
};
struct role_trans {
u32 role; /* current role */
u32 type; /* program executable type, or new object type */
u32 tclass; /* process class, or new object class */
u32 new_role; /* new role */
struct role_trans *next;
};
struct filename_trans {
u32 stype; /* current process */
u32 ttype; /* parent dir context */
u16 tclass; /* class of new object */
const char *name; /* last path component */
};
struct filename_trans_datum {
u32 otype; /* expected of new object */
};
struct role_allow {
u32 role; /* current role */
u32 new_role; /* new role */
struct role_allow *next;
};
/* Type attributes */
struct type_datum {
u32 value; /* internal type value */
SELinux: add boundary support and thread context assignment The purpose of this patch is to assign per-thread security context under a constraint. It enables multi-threaded server application to kick a request handler with its fair security context, and helps some of userspace object managers to handle user's request. When we assign a per-thread security context, it must not have wider permissions than the original one. Because a multi-threaded process shares a single local memory, an arbitary per-thread security context also means another thread can easily refer violated information. The constraint on a per-thread security context requires a new domain has to be equal or weaker than its original one, when it tries to assign a per-thread security context. Bounds relationship between two types is a way to ensure a domain can never have wider permission than its bounds. We can define it in two explicit or implicit ways. The first way is using new TYPEBOUNDS statement. It enables to define a boundary of types explicitly. The other one expand the concept of existing named based hierarchy. If we defines a type with "." separated name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t". This feature requires a new policy version. The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into kernel space, and the following patch enables to handle it. Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-08-28 09:35:57 +02:00
u32 bounds; /* boundary of type */
unsigned char primary; /* primary name? */
SELinux: add boundary support and thread context assignment The purpose of this patch is to assign per-thread security context under a constraint. It enables multi-threaded server application to kick a request handler with its fair security context, and helps some of userspace object managers to handle user's request. When we assign a per-thread security context, it must not have wider permissions than the original one. Because a multi-threaded process shares a single local memory, an arbitary per-thread security context also means another thread can easily refer violated information. The constraint on a per-thread security context requires a new domain has to be equal or weaker than its original one, when it tries to assign a per-thread security context. Bounds relationship between two types is a way to ensure a domain can never have wider permission than its bounds. We can define it in two explicit or implicit ways. The first way is using new TYPEBOUNDS statement. It enables to define a boundary of types explicitly. The other one expand the concept of existing named based hierarchy. If we defines a type with "." separated name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t". This feature requires a new policy version. The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into kernel space, and the following patch enables to handle it. Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-08-28 09:35:57 +02:00
unsigned char attribute;/* attribute ?*/
};
/* User attributes */
struct user_datum {
u32 value; /* internal user value */
SELinux: add boundary support and thread context assignment The purpose of this patch is to assign per-thread security context under a constraint. It enables multi-threaded server application to kick a request handler with its fair security context, and helps some of userspace object managers to handle user's request. When we assign a per-thread security context, it must not have wider permissions than the original one. Because a multi-threaded process shares a single local memory, an arbitary per-thread security context also means another thread can easily refer violated information. The constraint on a per-thread security context requires a new domain has to be equal or weaker than its original one, when it tries to assign a per-thread security context. Bounds relationship between two types is a way to ensure a domain can never have wider permission than its bounds. We can define it in two explicit or implicit ways. The first way is using new TYPEBOUNDS statement. It enables to define a boundary of types explicitly. The other one expand the concept of existing named based hierarchy. If we defines a type with "." separated name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t". This feature requires a new policy version. The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into kernel space, and the following patch enables to handle it. Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2008-08-28 09:35:57 +02:00
u32 bounds; /* bounds of user */
struct ebitmap roles; /* set of authorized roles for user */
struct mls_range range; /* MLS range (min - max) for user */
struct mls_level dfltlevel; /* default login MLS level for user */
};
/* Sensitivity attributes */
struct level_datum {
struct mls_level *level; /* sensitivity and associated categories */
unsigned char isalias; /* is this sensitivity an alias for another? */
};
/* Category attributes */
struct cat_datum {
u32 value; /* internal category bit + 1 */
unsigned char isalias; /* is this category an alias for another? */
};
struct range_trans {
u32 source_type;
u32 target_type;
u32 target_class;
};
/* Boolean data type */
struct cond_bool_datum {
__u32 value; /* internal type value */
int state;
};
struct cond_node;
/*
* The configuration data includes security contexts for
* initial SIDs, unlabeled file systems, TCP and UDP port numbers,
* network interfaces, and nodes. This structure stores the
* relevant data for one such entry. Entries of the same kind
* (e.g. all initial SIDs) are linked together into a list.
*/
struct ocontext {
union {
char *name; /* name of initial SID, fs, netif, fstype, path */
struct {
u8 protocol;
u16 low_port;
u16 high_port;
} port; /* TCP or UDP port information */
struct {
u32 addr;
u32 mask;
} node; /* node information */
struct {
u32 addr[4];
u32 mask[4];
} node6; /* IPv6 node information */
} u;
union {
u32 sclass; /* security class for genfs */
u32 behavior; /* labeling behavior for fs_use */
} v;
struct context context[2]; /* security context(s) */
u32 sid[2]; /* SID(s) */
struct ocontext *next;
};
struct genfs {
char *fstype;
struct ocontext *head;
struct genfs *next;
};
/* symbol table array indices */
#define SYM_COMMONS 0
#define SYM_CLASSES 1
#define SYM_ROLES 2
#define SYM_TYPES 3
#define SYM_USERS 4
#define SYM_BOOLS 5
#define SYM_LEVELS 6
#define SYM_CATS 7
#define SYM_NUM 8
/* object context array indices */
#define OCON_ISID 0 /* initial SIDs */
#define OCON_FS 1 /* unlabeled file systems */
#define OCON_PORT 2 /* TCP and UDP port numbers */
#define OCON_NETIF 3 /* network interfaces */
#define OCON_NODE 4 /* nodes */
#define OCON_FSUSE 5 /* fs_use */
#define OCON_NODE6 6 /* IPv6 nodes */
#define OCON_NUM 7
/* The policy database */
struct policydb {
int mls_enabled;
/* symbol tables */
struct symtab symtab[SYM_NUM];
#define p_commons symtab[SYM_COMMONS]
#define p_classes symtab[SYM_CLASSES]
#define p_roles symtab[SYM_ROLES]
#define p_types symtab[SYM_TYPES]
#define p_users symtab[SYM_USERS]
#define p_bools symtab[SYM_BOOLS]
#define p_levels symtab[SYM_LEVELS]
#define p_cats symtab[SYM_CATS]
/* symbol names indexed by (value - 1) */
struct flex_array *sym_val_to_name[SYM_NUM];
/* class, role, and user attributes indexed by (value - 1) */
struct class_datum **class_val_to_struct;
struct role_datum **role_val_to_struct;
struct user_datum **user_val_to_struct;
struct flex_array *type_val_to_struct_array;
/* type enforcement access vectors and transitions */
struct avtab te_avtab;
/* role transitions */
struct role_trans *role_tr;
/* file transitions with the last path component */
/* quickly exclude lookups when parent ttype has no rules */
struct ebitmap filename_trans_ttypes;
/* actual set of filename_trans rules */
struct hashtab *filename_trans;
/* bools indexed by (value - 1) */
struct cond_bool_datum **bool_val_to_struct;
/* type enforcement conditional access vectors and transitions */
struct avtab te_cond_avtab;
/* linked list indexing te_cond_avtab by conditional */
struct cond_node *cond_list;
/* role allows */
struct role_allow *role_allow;
/* security contexts of initial SIDs, unlabeled file systems,
TCP or UDP port numbers, network interfaces and nodes */
struct ocontext *ocontexts[OCON_NUM];
/* security contexts for files in filesystems that cannot support
a persistent label mapping or use another
fixed labeling behavior. */
struct genfs *genfs;
/* range transitions table (range_trans_key -> mls_range) */
struct hashtab *range_tr;
/* type -> attribute reverse mapping */
struct flex_array *type_attr_map_array;
struct ebitmap policycaps;
struct ebitmap permissive_map;
/* length of this policy when it was loaded */
size_t len;
unsigned int policyvers;
unsigned int reject_unknown : 1;
unsigned int allow_unknown : 1;
selinux: dynamic class/perm discovery Modify SELinux to dynamically discover class and permission values upon policy load, based on the dynamic object class/perm discovery logic from libselinux. A mapping is created between kernel-private class and permission indices used outside the security server and the policy values used within the security server. The mappings are only applied upon kernel-internal computations; similar mappings for the private indices of userspace object managers is handled on a per-object manager basis by the userspace AVC. The interfaces for compute_av and transition_sid are split for kernel vs. userspace; the userspace functions are distinguished by a _user suffix. The kernel-private class indices are no longer tied to the policy values and thus do not need to skip indices for userspace classes; thus the kernel class index values are compressed. The flask.h definitions were regenerated by deleting the userspace classes from refpolicy's definitions and then regenerating the headers. Going forward, we can just maintain the flask.h, av_permissions.h, and classmap.h definitions separately from policy as they are no longer tied to the policy values. The next patch introduces a utility to automate generation of flask.h and av_permissions.h from the classmap.h definitions. The older kernel class and permission string tables are removed and replaced by a single security class mapping table that is walked at policy load to generate the mapping. The old kernel class validation logic is completely replaced by the mapping logic. The handle unknown logic is reworked. reject_unknown=1 is handled when the mappings are computed at policy load time, similar to the old handling by the class validation logic. allow_unknown=1 is handled when computing and mapping decisions - if the permission was not able to be mapped (i.e. undefined, mapped to zero), then it is automatically added to the allowed vector. If the class was not able to be mapped (i.e. undefined, mapped to zero), then all permissions are allowed for it if allow_unknown=1. avc_audit leverages the new security class mapping table to lookup the class and permission names from the kernel-private indices. The mdp program is updated to use the new table when generating the class definitions and allow rules for a minimal boot policy for the kernel. It should be noted that this policy will not include any userspace classes, nor will its policy index values for the kernel classes correspond with the ones in refpolicy (they will instead match the kernel-private indices). Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-30 19:37:50 +02:00
u16 process_class;
u32 process_trans_perms;
};
extern void policydb_destroy(struct policydb *p);
extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
extern int policydb_context_isvalid(struct policydb *p, struct context *c);
extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
extern int policydb_read(struct policydb *p, void *fp);
extern int policydb_write(struct policydb *p, void *fp);
#define PERM_SYMTAB_SIZE 32
#define POLICYDB_CONFIG_MLS 1
/* the config flags related to unknown classes/perms are bits 2 and 3 */
#define REJECT_UNKNOWN 0x00000002
#define ALLOW_UNKNOWN 0x00000004
#define OBJECT_R "object_r"
#define OBJECT_R_VAL 1
#define POLICYDB_MAGIC SELINUX_MAGIC
#define POLICYDB_STRING "SE Linux"
struct policy_file {
char *data;
size_t len;
};
struct policy_data {
struct policydb *p;
void *fp;
};
static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
{
if (bytes > fp->len)
return -EINVAL;
memcpy(buf, fp->data, bytes);
fp->data += bytes;
fp->len -= bytes;
return 0;
}
static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
{
size_t len = bytes * num;
memcpy(fp->data, buf, len);
fp->data += len;
fp->len -= len;
return 0;
}
static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
{
struct flex_array *fa = p->sym_val_to_name[sym_num];
return flex_array_get_ptr(fa, element_nr);
}
selinux: dynamic class/perm discovery Modify SELinux to dynamically discover class and permission values upon policy load, based on the dynamic object class/perm discovery logic from libselinux. A mapping is created between kernel-private class and permission indices used outside the security server and the policy values used within the security server. The mappings are only applied upon kernel-internal computations; similar mappings for the private indices of userspace object managers is handled on a per-object manager basis by the userspace AVC. The interfaces for compute_av and transition_sid are split for kernel vs. userspace; the userspace functions are distinguished by a _user suffix. The kernel-private class indices are no longer tied to the policy values and thus do not need to skip indices for userspace classes; thus the kernel class index values are compressed. The flask.h definitions were regenerated by deleting the userspace classes from refpolicy's definitions and then regenerating the headers. Going forward, we can just maintain the flask.h, av_permissions.h, and classmap.h definitions separately from policy as they are no longer tied to the policy values. The next patch introduces a utility to automate generation of flask.h and av_permissions.h from the classmap.h definitions. The older kernel class and permission string tables are removed and replaced by a single security class mapping table that is walked at policy load to generate the mapping. The old kernel class validation logic is completely replaced by the mapping logic. The handle unknown logic is reworked. reject_unknown=1 is handled when the mappings are computed at policy load time, similar to the old handling by the class validation logic. allow_unknown=1 is handled when computing and mapping decisions - if the permission was not able to be mapped (i.e. undefined, mapped to zero), then it is automatically added to the allowed vector. If the class was not able to be mapped (i.e. undefined, mapped to zero), then all permissions are allowed for it if allow_unknown=1. avc_audit leverages the new security class mapping table to lookup the class and permission names from the kernel-private indices. The mdp program is updated to use the new table when generating the class definitions and allow rules for a minimal boot policy for the kernel. It should be noted that this policy will not include any userspace classes, nor will its policy index values for the kernel classes correspond with the ones in refpolicy (they will instead match the kernel-private indices). Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-30 19:37:50 +02:00
extern u16 string_to_security_class(struct policydb *p, const char *name);
extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
#endif /* _SS_POLICYDB_H_ */