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
15 struct scm_fp_list
16 {
17 struct list_head list;
18 int count;
19 struct file *fp[SCM_MAX_FD];
20 };
21
22 struct 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 unsigned long seq; /* Connection seqno */
30 };
31
32 extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
33 extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
34 extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
35 extern void __scm_destroy(struct scm_cookie *scm);
36 extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
37
38 #ifdef CONFIG_SECURITY_NETWORK
unix_get_peersec_dgram(struct socket * sock,struct scm_cookie * scm)39 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
40 {
41 security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
42 }
43 #else
unix_get_peersec_dgram(struct socket * sock,struct scm_cookie * scm)44 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
45 { }
46 #endif /* CONFIG_SECURITY_NETWORK */
47
scm_destroy(struct scm_cookie * scm)48 static __inline__ void scm_destroy(struct scm_cookie *scm)
49 {
50 if (scm && scm->fp)
51 __scm_destroy(scm);
52 }
53
scm_send(struct socket * sock,struct msghdr * msg,struct scm_cookie * scm)54 static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
55 struct scm_cookie *scm)
56 {
57 struct task_struct *p = current;
58 scm->creds.uid = current_uid();
59 scm->creds.gid = current_gid();
60 scm->creds.pid = task_tgid_vnr(p);
61 scm->fp = NULL;
62 scm->seq = 0;
63 unix_get_peersec_dgram(sock, scm);
64 if (msg->msg_controllen <= 0)
65 return 0;
66 return __scm_send(sock, msg, scm);
67 }
68
69 #ifdef CONFIG_SECURITY_NETWORK
scm_passec(struct socket * sock,struct msghdr * msg,struct scm_cookie * scm)70 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
71 {
72 char *secdata;
73 u32 seclen;
74 int err;
75
76 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
77 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
78
79 if (!err) {
80 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
81 security_release_secctx(secdata, seclen);
82 }
83 }
84 }
85 #else
scm_passec(struct socket * sock,struct msghdr * msg,struct scm_cookie * scm)86 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
87 { }
88 #endif /* CONFIG_SECURITY_NETWORK */
89
scm_recv(struct socket * sock,struct msghdr * msg,struct scm_cookie * scm,int flags)90 static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
91 struct scm_cookie *scm, int flags)
92 {
93 if (!msg->msg_control)
94 {
95 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
96 msg->msg_flags |= MSG_CTRUNC;
97 scm_destroy(scm);
98 return;
99 }
100
101 if (test_bit(SOCK_PASSCRED, &sock->flags))
102 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
103
104 scm_passec(sock, msg, scm);
105
106 if (!scm->fp)
107 return;
108
109 scm_detach_fds(msg, scm);
110 }
111
112
113 #endif /* __LINUX_NET_SCM_H */
114
115