linux/net/core/sock_diag.c

249 lines
5.7 KiB
C

#include <linux/mutex.h>
#include <linux/socket.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/net_namespace.h>
#include <linux/module.h>
#include <net/sock.h>
#include <linux/inet_diag.h>
#include <linux/sock_diag.h>
static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
static DEFINE_MUTEX(sock_diag_table_mutex);
static u64 sock_gen_cookie(struct sock *sk)
{
while (1) {
u64 res = atomic64_read(&sk->sk_cookie);
if (res)
return res;
res = atomic64_inc_return(&sock_net(sk)->cookie_gen);
atomic64_cmpxchg(&sk->sk_cookie, 0, res);
}
}
int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
{
u64 res;
if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE)
return 0;
res = sock_gen_cookie(sk);
if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1])
return -ESTALE;
return 0;
}
EXPORT_SYMBOL_GPL(sock_diag_check_cookie);
void sock_diag_save_cookie(struct sock *sk, __u32 *cookie)
{
u64 res = sock_gen_cookie(sk);
cookie[0] = (u32)res;
cookie[1] = (u32)(res >> 32);
}
EXPORT_SYMBOL_GPL(sock_diag_save_cookie);
int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype)
{
u32 mem[SK_MEMINFO_VARS];
mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
return nla_put(skb, attrtype, sizeof(mem), &mem);
}
EXPORT_SYMBOL_GPL(sock_diag_put_meminfo);
int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
struct sk_buff *skb, int attrtype)
{
struct sock_fprog_kern *fprog;
struct sk_filter *filter;
struct nlattr *attr;
unsigned int flen;
int err = 0;
if (!may_report_filterinfo) {
nla_reserve(skb, attrtype, 0);
return 0;
}
rcu_read_lock();
filter = rcu_dereference(sk->sk_filter);
if (!filter)
goto out;
fprog = filter->prog->orig_prog;
flen = bpf_classic_proglen(fprog);
attr = nla_reserve(skb, attrtype, flen);
if (attr == NULL) {
err = -EMSGSIZE;
goto out;
}
memcpy(nla_data(attr), fprog->filter, flen);
out:
rcu_read_unlock();
return err;
}
EXPORT_SYMBOL(sock_diag_put_filterinfo);
void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
{
mutex_lock(&sock_diag_table_mutex);
inet_rcv_compat = fn;
mutex_unlock(&sock_diag_table_mutex);
}
EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat);
void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
{
mutex_lock(&sock_diag_table_mutex);
inet_rcv_compat = NULL;
mutex_unlock(&sock_diag_table_mutex);
}
EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat);
int sock_diag_register(const struct sock_diag_handler *hndl)
{
int err = 0;
if (hndl->family >= AF_MAX)
return -EINVAL;
mutex_lock(&sock_diag_table_mutex);
if (sock_diag_handlers[hndl->family])
err = -EBUSY;
else
sock_diag_handlers[hndl->family] = hndl;
mutex_unlock(&sock_diag_table_mutex);
return err;
}
EXPORT_SYMBOL_GPL(sock_diag_register);
void sock_diag_unregister(const struct sock_diag_handler *hnld)
{
int family = hnld->family;
if (family >= AF_MAX)
return;
mutex_lock(&sock_diag_table_mutex);
BUG_ON(sock_diag_handlers[family] != hnld);
sock_diag_handlers[family] = NULL;
mutex_unlock(&sock_diag_table_mutex);
}
EXPORT_SYMBOL_GPL(sock_diag_unregister);
static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
int err;
struct sock_diag_req *req = nlmsg_data(nlh);
const struct sock_diag_handler *hndl;
if (nlmsg_len(nlh) < sizeof(*req))
return -EINVAL;
if (req->sdiag_family >= AF_MAX)
return -EINVAL;
if (sock_diag_handlers[req->sdiag_family] == NULL)
request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
NETLINK_SOCK_DIAG, req->sdiag_family);
mutex_lock(&sock_diag_table_mutex);
hndl = sock_diag_handlers[req->sdiag_family];
if (hndl == NULL)
err = -ENOENT;
else
err = hndl->dump(skb, nlh);
mutex_unlock(&sock_diag_table_mutex);
return err;
}
static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
int ret;
switch (nlh->nlmsg_type) {
case TCPDIAG_GETSOCK:
case DCCPDIAG_GETSOCK:
if (inet_rcv_compat == NULL)
request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
NETLINK_SOCK_DIAG, AF_INET);
mutex_lock(&sock_diag_table_mutex);
if (inet_rcv_compat != NULL)
ret = inet_rcv_compat(skb, nlh);
else
ret = -EOPNOTSUPP;
mutex_unlock(&sock_diag_table_mutex);
return ret;
case SOCK_DIAG_BY_FAMILY:
return __sock_diag_rcv_msg(skb, nlh);
default:
return -EINVAL;
}
}
static DEFINE_MUTEX(sock_diag_mutex);
static void sock_diag_rcv(struct sk_buff *skb)
{
mutex_lock(&sock_diag_mutex);
netlink_rcv_skb(skb, &sock_diag_rcv_msg);
mutex_unlock(&sock_diag_mutex);
}
static int __net_init diag_net_init(struct net *net)
{
struct netlink_kernel_cfg cfg = {
.input = sock_diag_rcv,
};
net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg);
return net->diag_nlsk == NULL ? -ENOMEM : 0;
}
static void __net_exit diag_net_exit(struct net *net)
{
netlink_kernel_release(net->diag_nlsk);
net->diag_nlsk = NULL;
}
static struct pernet_operations diag_net_ops = {
.init = diag_net_init,
.exit = diag_net_exit,
};
static int __init sock_diag_init(void)
{
return register_pernet_subsys(&diag_net_ops);
}
static void __exit sock_diag_exit(void)
{
unregister_pernet_subsys(&diag_net_ops);
}
module_init(sock_diag_init);
module_exit(sock_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG);