tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef __LINUX_NET_SCM_H
2#define __LINUX_NET_SCM_H
3
4#include <linux/limits.h>
5#include <linux/net.h>
6#include <linux/security.h>
7#include <linux/pid.h>
8#include <linux/nsproxy.h>
9
10/* Well, we should have at least one descriptor open
11 * to accept passed FDs 8)
12 */
13#define SCM_MAX_FD 255
14
15struct scm_fp_list
16{
17 struct list_head list;
18 int count;
19 struct file *fp[SCM_MAX_FD];
20};
21
22struct scm_cookie
23{
24 struct ucred creds; /* Skb credentials */
25 struct scm_fp_list *fp; /* Passed files */
26#ifdef CONFIG_SECURITY_NETWORK
27 u32 secid; /* Passed security ID */
28#endif
29};
30
31extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
32extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
33extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
34extern void __scm_destroy(struct scm_cookie *scm);
35extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
36
37#ifdef CONFIG_SECURITY_NETWORK
38static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
39{
40 security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
41}
42#else
43static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
44{ }
45#endif /* CONFIG_SECURITY_NETWORK */
46
47static __inline__ void scm_destroy(struct scm_cookie *scm)
48{
49 if (scm && scm->fp)
50 __scm_destroy(scm);
51}
52
53static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
54 struct scm_cookie *scm)
55{
56 struct task_struct *p = current;
57 scm->creds.uid = current_uid();
58 scm->creds.gid = current_gid();
59 scm->creds.pid = task_tgid_vnr(p);
60 scm->fp = NULL;
61 unix_get_peersec_dgram(sock, scm);
62 if (msg->msg_controllen <= 0)
63 return 0;
64 return __scm_send(sock, msg, scm);
65}
66
67#ifdef CONFIG_SECURITY_NETWORK
68static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
69{
70 char *secdata;
71 u32 seclen;
72 int err;
73
74 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
75 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
76
77 if (!err) {
78 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
79 security_release_secctx(secdata, seclen);
80 }
81 }
82}
83#else
84static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
85{ }
86#endif /* CONFIG_SECURITY_NETWORK */
87
88static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
89 struct scm_cookie *scm, int flags)
90{
91 if (!msg->msg_control)
92 {
93 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
94 msg->msg_flags |= MSG_CTRUNC;
95 scm_destroy(scm);
96 return;
97 }
98
99 if (test_bit(SOCK_PASSCRED, &sock->flags))
100 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
101
102 scm_passec(sock, msg, scm);
103
104 if (!scm->fp)
105 return;
106
107 scm_detach_fds(msg, scm);
108}
109
110
111#endif /* __LINUX_NET_SCM_H */
112