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 struct list_head list;
17 int count;
18 struct file *fp[SCM_MAX_FD];
19};
20
21struct scm_cookie {
22 struct ucred creds; /* Skb credentials */
23 struct scm_fp_list *fp; /* Passed files */
24#ifdef CONFIG_SECURITY_NETWORK
25 u32 secid; /* Passed security ID */
26#endif
27};
28
29extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
30extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
31extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
32extern void __scm_destroy(struct scm_cookie *scm);
33extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
34
35#ifdef CONFIG_SECURITY_NETWORK
36static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
37{
38 security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
39}
40#else
41static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
42{ }
43#endif /* CONFIG_SECURITY_NETWORK */
44
45static __inline__ void scm_destroy(struct scm_cookie *scm)
46{
47 if (scm && scm->fp)
48 __scm_destroy(scm);
49}
50
51static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
52 struct scm_cookie *scm)
53{
54 struct task_struct *p = current;
55 scm->creds.uid = current_uid();
56 scm->creds.gid = current_gid();
57 scm->creds.pid = task_tgid_vnr(p);
58 scm->fp = NULL;
59 unix_get_peersec_dgram(sock, scm);
60 if (msg->msg_controllen <= 0)
61 return 0;
62 return __scm_send(sock, msg, scm);
63}
64
65#ifdef CONFIG_SECURITY_NETWORK
66static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
67{
68 char *secdata;
69 u32 seclen;
70 int err;
71
72 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
73 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
74
75 if (!err) {
76 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
77 security_release_secctx(secdata, seclen);
78 }
79 }
80}
81#else
82static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
83{ }
84#endif /* CONFIG_SECURITY_NETWORK */
85
86static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
87 struct scm_cookie *scm, int flags)
88{
89 if (!msg->msg_control) {
90 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
91 msg->msg_flags |= MSG_CTRUNC;
92 scm_destroy(scm);
93 return;
94 }
95
96 if (test_bit(SOCK_PASSCRED, &sock->flags))
97 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
98
99 scm_passec(sock, msg, scm);
100
101 if (!scm->fp)
102 return;
103
104 scm_detach_fds(msg, scm);
105}
106
107
108#endif /* __LINUX_NET_SCM_H */
109