blob: 745460fa2f02cdd96e6b6befd79b8791d95965fd [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef __LINUX_NET_SCM_H
2#define __LINUX_NET_SCM_H
3
4#include <linux/limits.h>
5#include <linux/net.h>
Catherine Zhangdc49c1f2006-08-02 14:12:06 -07006#include <linux/security.h>
Pavel Emelyanovb4888932007-10-18 23:40:14 -07007#include <linux/pid.h>
8#include <linux/nsproxy.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07009
10/* Well, we should have at least one descriptor open
11 * to accept passed FDs 8)
12 */
Eric Dumazetbba14de2010-11-23 14:09:15 +000013#define SCM_MAX_FD 253
Linus Torvalds1da177e2005-04-16 15:20:36 -070014
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000015struct scm_fp_list {
David Millerf8d570a2008-11-06 00:37:40 -080016 struct list_head list;
Eric Dumazetbba14de2010-11-23 14:09:15 +000017 short count;
18 short max;
David Millerf8d570a2008-11-06 00:37:40 -080019 struct file *fp[SCM_MAX_FD];
Linus Torvalds1da177e2005-04-16 15:20:36 -070020};
21
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +000022struct scm_cookie {
Eric W. Biederman257b5352010-06-13 03:32:34 +000023 struct pid *pid; /* Skb credentials */
24 const struct cred *cred;
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 struct scm_fp_list *fp; /* Passed files */
Eric W. Biederman812e8762010-06-13 03:27:04 +000026 struct ucred creds; /* Skb credentials */
Catherine Zhang877ce7c2006-06-29 12:27:47 -070027#ifdef CONFIG_SECURITY_NETWORK
Catherine Zhangdc49c1f2006-08-02 14:12:06 -070028 u32 secid; /* Passed security ID */
Catherine Zhang877ce7c2006-06-29 12:27:47 -070029#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070030};
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
Catherine Zhangdc49c1f2006-08-02 14:12:06 -070038#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
Eric W. Biederman257b5352010-06-13 03:32:34 +000048static __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 = get_cred(cred);
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070066static __inline__ void scm_destroy(struct scm_cookie *scm)
67{
Eric W. Biederman257b5352010-06-13 03:32:34 +000068 scm_destroy_cred(scm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 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{
Eric W. Biederman257b5352010-06-13 03:32:34 +000076 scm_set_cred(scm, task_tgid(current), current_cred());
Benjamin LaHaise1d541dd2006-03-20 21:31:51 -080077 scm->fp = NULL;
Catherine Zhangdc49c1f2006-08-02 14:12:06 -070078 unix_get_peersec_dgram(sock, scm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 if (msg->msg_controllen <= 0)
80 return 0;
81 return __scm_send(sock, msg, scm);
82}
83
Catherine Zhang877ce7c2006-06-29 12:27:47 -070084#ifdef CONFIG_SECURITY_NETWORK
85static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
86{
Catherine Zhangdc49c1f2006-08-02 14:12:06 -070087 char *secdata;
88 u32 seclen;
89 int err;
90
91 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
92 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
93
94 if (!err) {
95 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
96 security_release_secctx(secdata, seclen);
97 }
98 }
Catherine Zhang877ce7c2006-06-29 12:27:47 -070099}
100#else
101static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
102{ }
103#endif /* CONFIG_SECURITY_NETWORK */
104
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
106 struct scm_cookie *scm, int flags)
107{
Eric Dumazetfd2c3ef2009-11-03 03:26:03 +0000108 if (!msg->msg_control) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
110 msg->msg_flags |= MSG_CTRUNC;
111 scm_destroy(scm);
112 return;
113 }
114
115 if (test_bit(SOCK_PASSCRED, &sock->flags))
116 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(scm->creds), &scm->creds);
117
Eric W. Biederman257b5352010-06-13 03:32:34 +0000118 scm_destroy_cred(scm);
119
Catherine Zhang877ce7c2006-06-29 12:27:47 -0700120 scm_passec(sock, msg, scm);
121
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 if (!scm->fp)
123 return;
124
125 scm_detach_fds(msg, scm);
126}
127
128
129#endif /* __LINUX_NET_SCM_H */
130