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192.168.1.100 / T106_DC / 4533d5f3498a591e58619e63ecd1c18d98c91b40 / . / ap / os / linux / linux-3.4.x / include / net / scm.h
blob: 9f211cff93bcaf1d26ed3b2fbac59329fb328f94 [file] [log] [blame]
lh9ed821d2023-04-07 01:36:19 -0700[diff] [blame]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, false);
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, bool forcecreds)
75{
76 memset(scm, 0, sizeof(*scm));
77 if (forcecreds)
78 scm_set_cred(scm, task_tgid(current), current_cred());
79 unix_get_peersec_dgram(sock, scm);
80 if (msg->msg_controllen <= 0)
81 return 0;
82 return __scm_send(sock, msg, scm);
83}
84
85#ifdef CONFIG_SECURITY_NETWORK
86static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
87{
88 char *secdata;
89 u32 seclen;
90 int err;
91
92 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
93 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
94
95 if (!err) {
96 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
97 security_release_secctx(secdata, seclen);
98 }
99 }
100}
101#else
102static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
103{ }
104#endif /* CONFIG_SECURITY_NETWORK */
105
106static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
107 struct scm_cookie *scm, int flags)
108{
109 if (!msg->msg_control) {
110 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
111 msg->msg_flags |= MSG_CTRUNC;
112 scm_destroy(scm);
113 return;
114 }
115
116 if (test_bit(SOCK_PASSCRED, &sock->flags))
117 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
118
119 scm_destroy_cred(scm);
120
121 scm_passec(sock, msg, scm);
122
123 if (!scm->fp)
124 return;
125
126 scm_detach_fds(msg, scm);
127}
128
129
130#endif /* __LINUX_NET_SCM_H */
131