1 #ifndef __LINUX_NET_SCM_H
2 #define __LINUX_NET_SCM_H
4 #include <linux/limits.h>
6 #include <linux/security.h>
8 #include <linux/nsproxy.h>
10 /* Well, we should have at least one descriptor open
11 * to accept passed FDs 8)
13 #define SCM_MAX_FD 253
24 struct file *fp[SCM_MAX_FD];
28 struct pid *pid; /* Skb credentials */
29 const struct cred *cred;
30 struct scm_fp_list *fp; /* Passed files */
31 struct scm_creds creds; /* Skb credentials */
32 #ifdef CONFIG_SECURITY_NETWORK
33 u32 secid; /* Passed security ID */
37 extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
38 extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
39 extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
40 extern void __scm_destroy(struct scm_cookie *scm);
41 extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);
43 #ifdef CONFIG_SECURITY_NETWORK
44 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
46 security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
49 static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
51 #endif /* CONFIG_SECURITY_NETWORK */
53 static __inline__ void scm_set_cred(struct scm_cookie *scm,
54 struct pid *pid, const struct cred *cred)
56 scm->pid = get_pid(pid);
57 scm->cred = cred ? get_cred(cred) : NULL;
58 scm->creds.pid = pid_vnr(pid);
59 scm->creds.uid = cred ? cred->euid : INVALID_UID;
60 scm->creds.gid = cred ? cred->egid : INVALID_GID;
63 static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
73 static __inline__ void scm_destroy(struct scm_cookie *scm)
75 scm_destroy_cred(scm);
80 static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
81 struct scm_cookie *scm, bool forcecreds)
83 memset(scm, 0, sizeof(*scm));
85 scm_set_cred(scm, task_tgid(current), current_cred());
86 unix_get_peersec_dgram(sock, scm);
87 if (msg->msg_controllen <= 0)
89 return __scm_send(sock, msg, scm);
92 #ifdef CONFIG_SECURITY_NETWORK
93 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
99 if (test_bit(SOCK_PASSSEC, &sock->flags)) {
100 err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
103 put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
104 security_release_secctx(secdata, seclen);
109 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
111 #endif /* CONFIG_SECURITY_NETWORK */
113 static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
114 struct scm_cookie *scm, int flags)
116 if (!msg->msg_control) {
117 if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
118 msg->msg_flags |= MSG_CTRUNC;
123 if (test_bit(SOCK_PASSCRED, &sock->flags)) {
124 struct user_namespace *current_ns = current_user_ns();
125 struct ucred ucreds = {
126 .pid = scm->creds.pid,
127 .uid = from_kuid_munged(current_ns, scm->creds.uid),
128 .gid = from_kgid_munged(current_ns, scm->creds.gid),
130 put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(ucreds), &ucreds);
133 scm_destroy_cred(scm);
135 scm_passec(sock, msg, scm);
140 scm_detach_fds(msg, scm);
144 #endif /* __LINUX_NET_SCM_H */