Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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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
8/* Well, we should have at least one descriptor open
9 * to accept passed FDs 8)
10 */
11#define SCM_MAX_FD (OPEN_MAX-1)
12
13struct scm_fp_list
14{
15 int count;
16 struct file *fp[SCM_MAX_FD];
17};
18
19struct scm_cookie
20{
21 struct ucred creds; /* Skb credentials */
22 struct scm_fp_list *fp; /* Passed files */
23#ifdef CONFIG_SECURITY_NETWORK
24 u32 secid; /* Passed security ID */
25#endif
26 unsigned long seq; /* Connection seqno */
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 = p->uid;
56 scm->creds.gid = p->gid;
57 scm->creds.pid = p->tgid;
58 scm->fp = NULL;
59 scm->seq = 0;
60 unix_get_peersec_dgram(sock, scm);
61 if (msg->msg_controllen <= 0)
62 return 0;
63 return __scm_send(sock, msg, scm);
64}
65
66#ifdef CONFIG_SECURITY_NETWORK
67static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
68{
69 char *secdata;
70 u32 seclen;
71 int err;
72
73 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
74 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
75
76 if (!err) {
77 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
78 security_release_secctx(secdata, seclen);
79 }
80 }
81}
82#else
83static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
84{ }
85#endif /* CONFIG_SECURITY_NETWORK */
86
87static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
88 struct scm_cookie *scm, int flags)
89{
90 if (!msg->msg_control)
91 {
92 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
93 msg->msg_flags |= MSG_CTRUNC;
94 scm_destroy(scm);
95 return;
96 }
97
98 if (test_bit(SOCK_PASSCRED, &sock->flags))
99 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
100
101 scm_passec(sock, msg, scm);
102
103 if (!scm->fp)
104 return;
105
106 scm_detach_fds(msg, scm);
107}
108
109
110#endif /* __LINUX_NET_SCM_H */
111