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#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 253
14
15struct scm_fp_list {
16 struct list_head list;
17 short count;
18 short max;
19 struct file *fp[SCM_MAX_FD];
20};
21
22struct scm_cookie {
23 struct pid *pid; /* Skb credentials */
24 const struct cred *cred;
25 struct scm_fp_list *fp; /* Passed files */
26 struct ucred creds; /* Skb credentials */
27#ifdef CONFIG_SECURITY_NETWORK
28 u32 secid; /* Passed security ID */
29#endif
30};
31
32extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
33extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
34extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
35extern void __scm_destroy(struct scm_cookie *scm);
36extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
37
38#ifdef CONFIG_SECURITY_NETWORK
39static __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
44static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
45{ }
46#endif /* CONFIG_SECURITY_NETWORK */
47
48static __inline__ void scm_set_cred(struct scm_cookie *scm,
49 struct pid *pid, const struct cred *cred)
50{
51 scm->pid = get_pid(pid);
52 scm->cred = cred ? get_cred(cred) : NULL;
53 cred_to_ucred(pid, cred, &scm->creds);
54}
55
56static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
57{
58 put_pid(scm->pid);
59 scm->pid = NULL;
60
61 if (scm->cred)
62 put_cred(scm->cred);
63 scm->cred = NULL;
64}
65
66static __inline__ void scm_destroy(struct scm_cookie *scm)
67{
68 scm_destroy_cred(scm);
69 if (scm && scm->fp)
70 __scm_destroy(scm);
71}
72
73static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
74 struct scm_cookie *scm)
75{
76 memset(scm, 0, sizeof(*scm));
77 unix_get_peersec_dgram(sock, scm);
78 if (msg->msg_controllen <= 0)
79 return 0;
80 return __scm_send(sock, msg, scm);
81}
82
83#ifdef CONFIG_SECURITY_NETWORK
84static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
85{
86 char *secdata;
87 u32 seclen;
88 int err;
89
90 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
91 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
92
93 if (!err) {
94 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
95 security_release_secctx(secdata, seclen);
96 }
97 }
98}
99#else
100static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
101{ }
102#endif /* CONFIG_SECURITY_NETWORK */
103
104static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
105 struct scm_cookie *scm, int flags)
106{
107 if (!msg->msg_control) {
108 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
109 msg->msg_flags |= MSG_CTRUNC;
110 scm_destroy(scm);
111 return;
112 }
113
114 if (test_bit(SOCK_PASSCRED, &sock->flags))
115 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
116
117 scm_destroy_cred(scm);
118
119 scm_passec(sock, msg, scm);
120
121 if (!scm->fp)
122 return;
123
124 scm_detach_fds(msg, scm);
125}
126
127
128#endif /* __LINUX_NET_SCM_H */
129