[linux-2.6-block.git] / include / net / scm.h

#ifndef __LINUX_NET_SCM_H
#define __LINUX_NET_SCM_H

#include <linux/limits.h>
#include <linux/net.h>
#include <linux/security.h>
#include <linux/pid.h>
#include <linux/nsproxy.h>

/* Well, we should have at least one descriptor open
 * to accept passed FDs 8)
 */
#define SCM_MAX_FD	253

struct scm_creds {
	u32	pid;
	kuid_t	uid;
	kgid_t	gid;
};

struct scm_fp_list {
	short			count;
	short			max;
	struct file		*fp[SCM_MAX_FD];
};

struct scm_cookie {
	struct pid		*pid;		/* Skb credentials */
	const struct cred	*cred;
	struct scm_fp_list	*fp;		/* Passed files		*/
	struct scm_creds	creds;		/* Skb credentials	*/
#ifdef CONFIG_SECURITY_NETWORK
	u32			secid;		/* Passed security ID 	*/
#endif
};

extern void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm);
extern void scm_detach_fds_compat(struct msghdr *msg, struct scm_cookie *scm);
extern int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm);
extern void __scm_destroy(struct scm_cookie *scm);
extern struct scm_fp_list * scm_fp_dup(struct scm_fp_list *fpl);

#ifdef CONFIG_SECURITY_NETWORK
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
{
	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
}
#else
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
{ }
#endif /* CONFIG_SECURITY_NETWORK */

static __inline__ void scm_set_cred(struct scm_cookie *scm,
				    struct pid *pid, const struct cred *cred)
{
	scm->pid  = get_pid(pid);
	scm->cred = cred ? get_cred(cred) : NULL;
	scm->creds.pid = pid_vnr(pid);
	scm->creds.uid = cred ? cred->euid : INVALID_UID;
	scm->creds.gid = cred ? cred->egid : INVALID_GID;
}

static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
{
	put_pid(scm->pid);
	scm->pid  = NULL;

	if (scm->cred)
		put_cred(scm->cred);
	scm->cred = NULL;
}

static __inline__ void scm_destroy(struct scm_cookie *scm)
{
	scm_destroy_cred(scm);
	if (scm->fp)
		__scm_destroy(scm);
}

static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
			       struct scm_cookie *scm, bool forcecreds)
{
	memset(scm, 0, sizeof(*scm));
	if (forcecreds)
		scm_set_cred(scm, task_tgid(current), current_cred());
	unix_get_peersec_dgram(sock, scm);
	if (msg->msg_controllen <= 0)
		return 0;
	return __scm_send(sock, msg, scm);
}

#ifdef CONFIG_SECURITY_NETWORK
static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
{
	char *secdata;
	u32 seclen;
	int err;

	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
		err = security_secid_to_secctx(scm->secid, &secdata, &seclen);

		if (!err) {
			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
			security_release_secctx(secdata, seclen);
		}
	}
}
#else
static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
{ }
#endif /* CONFIG_SECURITY_NETWORK */

static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg,
				struct scm_cookie *scm, int flags)
{
	if (!msg->msg_control) {
		if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp)
			msg->msg_flags |= MSG_CTRUNC;
		scm_destroy(scm);
		return;
	}

	if (test_bit(SOCK_PASSCRED, &sock->flags)) {
		struct user_namespace *current_ns = current_user_ns();
		struct ucred ucreds = {
			.pid = scm->creds.pid,
			.uid = from_kuid_munged(current_ns, scm->creds.uid),
			.gid = from_kgid_munged(current_ns, scm->creds.gid),
		};
		put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(ucreds), &ucreds);
	}

	scm_destroy_cred(scm);

	scm_passec(sock, msg, scm);

	if (!scm->fp)
		return;
	
	scm_detach_fds(msg, scm);
}


#endif /* __LINUX_NET_SCM_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef __LINUX_NET_SCM_H
	2	#define __LINUX_NET_SCM_H
	3
	4	#include <linux/limits.h>
	5	#include <linux/net.h>
dc49c1f9	6	#include <linux/security.h>
b488893a PE	7	#include <linux/pid.h>
b488893a PE	8	#include <linux/nsproxy.h>
1da177e4 LT	9
	10	/* Well, we should have at least one descriptor open
	11	* to accept passed FDs 8)
	12	*/
bba14de9	13	#define SCM_MAX_FD 253
1da177e4	14
dbe9a417 EB	15	struct scm_creds {
	16	u32 pid;
	17	kuid_t uid;
	18	kgid_t gid;
	19	};
	20
fd2c3ef7	21	struct scm_fp_list {
bba14de9 ED	22	short count;
bba14de9 ED	23	short max;
f8d570a4	24	struct file *fp[SCM_MAX_FD];
1da177e4 LT	25	};
1da177e4 LT	26
fd2c3ef7	27	struct scm_cookie {
257b5358 EB	28	struct pid pid; / Skb credentials */
257b5358 EB	29	const struct cred *cred;
1da177e4	30	struct scm_fp_list fp; / Passed files */
dbe9a417	31	struct scm_creds creds; /* Skb credentials */
877ce7c1	32	#ifdef CONFIG_SECURITY_NETWORK
dc49c1f9	33	u32 secid; /* Passed security ID */
877ce7c1	34	#endif
1da177e4 LT	35	};
	36
	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);
	42
dc49c1f9 CZ	43	#ifdef CONFIG_SECURITY_NETWORK
	44	static __inline__ void unix_get_peersec_dgram(struct socket sock, struct scm_cookie scm)
	45	{
	46	security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
	47	}
	48	#else
	49	static __inline__ void unix_get_peersec_dgram(struct socket sock, struct scm_cookie scm)
	50	{ }
	51	#endif /* CONFIG_SECURITY_NETWORK */
	52
257b5358 EB	53	static __inline__ void scm_set_cred(struct scm_cookie *scm,
	54	struct pid pid, const struct cred cred)
	55	{
	56	scm->pid = get_pid(pid);
16e57262	57	scm->cred = cred ? get_cred(cred) : NULL;
dbe9a417 EB	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;
257b5358 EB	61	}
	62
	63	static __inline__ void scm_destroy_cred(struct scm_cookie *scm)
	64	{
	65	put_pid(scm->pid);
	66	scm->pid = NULL;
	67
	68	if (scm->cred)
	69	put_cred(scm->cred);
	70	scm->cred = NULL;
	71	}
	72
1da177e4 LT	73	static __inline__ void scm_destroy(struct scm_cookie *scm)
1da177e4 LT	74	{
257b5358	75	scm_destroy_cred(scm);
2a6c8c79	76	if (scm->fp)
1da177e4 LT	77	__scm_destroy(scm);
	78	}
	79
	80	static __inline__ int scm_send(struct socket sock, struct msghdr msg,
e0e3cea4	81	struct scm_cookie *scm, bool forcecreds)
1da177e4	82	{
16e57262	83	memset(scm, 0, sizeof(*scm));
e0e3cea4 ED	84	if (forcecreds)
e0e3cea4 ED	85	scm_set_cred(scm, task_tgid(current), current_cred());
dc49c1f9	86	unix_get_peersec_dgram(sock, scm);
1da177e4 LT	87	if (msg->msg_controllen <= 0)
	88	return 0;
	89	return __scm_send(sock, msg, scm);
	90	}
	91
877ce7c1 CZ	92	#ifdef CONFIG_SECURITY_NETWORK
	93	static inline void scm_passec(struct socket sock, struct msghdr msg, struct scm_cookie *scm)
	94	{
dc49c1f9 CZ	95	char *secdata;
	96	u32 seclen;
	97	int err;
	98
	99	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
	100	err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
	101
	102	if (!err) {
	103	put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
	104	security_release_secctx(secdata, seclen);
	105	}
	106	}
877ce7c1 CZ	107	}
	108	#else
	109	static inline void scm_passec(struct socket sock, struct msghdr msg, struct scm_cookie *scm)
	110	{ }
	111	#endif /* CONFIG_SECURITY_NETWORK */
	112
1da177e4 LT	113	static __inline__ void scm_recv(struct socket sock, struct msghdr msg,
	114	struct scm_cookie *scm, int flags)
	115	{
fd2c3ef7	116	if (!msg->msg_control) {
1da177e4 LT	117	if (test_bit(SOCK_PASSCRED, &sock->flags) \|\| scm->fp)
1da177e4 LT	118	msg->msg_flags \|= MSG_CTRUNC;
f78a5fda	119	scm_destroy(scm);
1da177e4 LT	120	return;
	121	}
	122
dbe9a417 EB	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),
	129	};
	130	put_cmsg(msg, SOL_SOCKET, SCM_CREDENTIALS, sizeof(ucreds), &ucreds);
	131	}
1da177e4	132
f78a5fda DM	133	scm_destroy_cred(scm);
f78a5fda DM	134
877ce7c1 CZ	135	scm_passec(sock, msg, scm);
877ce7c1 CZ	136
1da177e4 LT	137	if (!scm->fp)
	138	return;
	139
	140	scm_detach_fds(msg, scm);
	141	}
	142
	143
	144	#endif /* __LINUX_NET_SCM_H */
	145