MLSXFRM: Default labeling of socket specific IPSec policies

This defaults the label of socket-specific IPSec policies to be the same as the socket they are set on.

---

include/linux/security.h        |   19 ++++++++++++++---
include/net/xfrm.h              |    2 -
net/key/af_key.c                |   15 ++++++++++---
net/xfrm/xfrm_state.c           |    2 -
net/xfrm/xfrm_user.c            |   13 ++++++++++-
security/dummy.c                |    3 +-
security/selinux/include/xfrm.h |    3 +-
security/selinux/xfrm.c         |   33 ++++++++++++++++++++----------
8 files changed, 66 insertions(+), 24 deletions(-)

@@ -826,8 +826,10 @@ struct swap_info_struct;
 *	used by the XFRM system.
 *	@sec_ctx contains the security context information being provided by
 *	the user-level policy update program (e.g., setkey).
+ *	@sk refers to the sock from which to derive the security context.
 *	Allocate a security structure to the xp->security field; the security
- *	field is initialized to NULL when the xfrm_policy is allocated.
+ *	field is initialized to NULL when the xfrm_policy is allocated. Only
+ *	one of sec_ctx or sock can be specified.
 *	Return 0 if operation was successful (memory to allocate, legal context)
 * @xfrm_policy_clone_security:
 *	@old contains an existing xfrm_policy in the SPD.

@@ -1346,7 +1348,8 @@ struct security_operations {

#endif /* CONFIG_SECURITY_NETWORK */

#ifdef CONFIG_SECURITY_NETWORK_XFRM
- int (*xfrm_policy_alloc_security) (struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx);
+ int (*xfrm_policy_alloc_security) (struct xfrm_policy *xp,

+			struct xfrm_user_sec_ctx *sec_ctx, struct sock *sk);
	int (*xfrm_policy_clone_security) (struct xfrm_policy *old, struct xfrm_policy *new);
	void (*xfrm_policy_free_security) (struct xfrm_policy *xp);
	int (*xfrm_policy_delete_security) (struct xfrm_policy *xp);

@@ -3028,7 +3031,12 @@ static inline void security_sk_secid(str
#ifdef CONFIG_SECURITY_NETWORK_XFRM
static inline int security_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx) {
- return security_ops->xfrm_policy_alloc_security(xp, sec_ctx);
+ return security_ops->xfrm_policy_alloc_security(xp, sec_ctx, NULL);
+}
+
+static inline int security_xfrm_sock_policy_alloc(struct xfrm_policy *xp, struct sock *sk) +{
+ return security_ops->xfrm_policy_alloc_security(xp, NULL, sk);
}

static inline int security_xfrm_policy_clone(struct xfrm_policy *old, struct xfrm_policy *new) @@ -3101,6 +3109,11 @@ static inline int security_xfrm_policy_a

	return 0;
}

+static inline int security_xfrm_sock_policy_alloc(struct xfrm_policy *xp, struct sock *sk) +{
+ return 0;
+}
+
static inline int security_xfrm_policy_clone(struct xfrm_policy *old, struct xfrm_policy *new)

{
	return 0;

@@ -363,7 +363,7 @@ struct xfrm_mgr

	char			*id;
	int			(*notify)(struct xfrm_state *x, struct km_event *c);
	int			(*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
-	struct xfrm_policy	*(*compile_policy)(u16 family, int opt, u8 *data, int len, int *dir);
+	struct xfrm_policy	*(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
	int			(*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
	int			(*notify_policy)(struct xfrm_policy *x, int dir, struct km_event *c);
};

@@ -816,7 +816,8 @@ static inline void dummy_sk_getsecid(str

#endif /* CONFIG_SECURITY_NETWORK */

#ifdef CONFIG_SECURITY_NETWORK_XFRM
-static int dummy_xfrm_policy_alloc_security(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx) +static int dummy_xfrm_policy_alloc_security(struct xfrm_policy *xp,
+ struct xfrm_user_sec_ctx *sec_ctx, struct sock *sk)

{
	return 0;
}

@@ -7,7 +7,8 @@

#ifndef _SELINUX_XFRM_H_
#define _SELINUX_XFRM_H_

-int selinux_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx); +int selinux_xfrm_policy_alloc(struct xfrm_policy *xp,
+ struct xfrm_user_sec_ctx *sec_ctx, struct sock *sk);
int selinux_xfrm_policy_clone(struct xfrm_policy *old, struct xfrm_policy *new); void selinux_xfrm_policy_free(struct xfrm_policy *xp);
int selinux_xfrm_policy_delete(struct xfrm_policy *xp);

@@ -208,10 +208,8 @@ static int selinux_xfrm_sec_ctx_alloc(st
 

	BUG_ON(uctx && pol);

- if (pol)
- goto from_policy;
-
- BUG_ON(!uctx);
+ if (!uctx)
+ goto not_from_user;

	if (uctx->ctx_doi != XFRM_SC_ALG_SELINUX)
		return -EINVAL;

@@ -251,11 +249,14 @@ static int selinux_xfrm_sec_ctx_alloc(st

	return rc;

-from_policy:
- BUG_ON(!pol);
- rc = security_sid_mls_copy(pol->ctx_sid, sid, &ctx_sid);
- if (rc)
- goto out;
+not_from_user:
+ if (pol) {
+ rc = security_sid_mls_copy(pol->ctx_sid, sid, &ctx_sid);
+ if (rc)
+ goto out;
+ }
+ else
+ ctx_sid = sid;

	rc = security_sid_to_context(ctx_sid, &ctx_str, &str_len);
	if (rc)

@@ -293,13 +294,23 @@ out2:
* LSM hook implementation that allocs and transfers uctx spec to
* xfrm_policy.
*/
-int selinux_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *uctx) +int selinux_xfrm_policy_alloc(struct xfrm_policy *xp,
+ struct xfrm_user_sec_ctx *uctx, struct sock *sk)

{
	int err;

+ u32 sid;

	BUG_ON(!xp);

+ BUG_ON(uctx && sk);
+
+ if (sk) {
+ struct sk_security_struct *ssec = sk->sk_security;
+ sid = ssec->sid;
+ }
+ else
+ sid = SECSID_NULL;

- err = selinux_xfrm_sec_ctx_alloc(&xp->security, uctx, NULL, 0);

+	err = selinux_xfrm_sec_ctx_alloc(&xp->security, uctx, NULL, sid);
	return err;
}

@@ -2843,14 +2843,14 @@ static int pfkey_send_acquire(struct xfr

	return pfkey_broadcast(skb, GFP_ATOMIC, BROADCAST_REGISTERED, NULL);
}

-static struct xfrm_policy *pfkey_compile_policy(u16 family, int opt, +static struct xfrm_policy *pfkey_compile_policy(struct sock *sk, int opt,
u8 *data, int len, int *dir)

{
	struct xfrm_policy *xp;
	struct sadb_x_policy *pol = (struct sadb_x_policy*)data;
	struct sadb_x_sec_ctx *sec_ctx;

- switch (family) {

+	switch (sk->sk_family) {
	case AF_INET:
		if (opt != IP_IPSEC_POLICY) {
			*dir = -EOPNOTSUPP;
@@ -2891,7 +2891,7 @@ static struct xfrm_policy *pfkey_compile
	xp->lft.hard_byte_limit = XFRM_INF;
	xp->lft.soft_packet_limit = XFRM_INF;
	xp->lft.hard_packet_limit = XFRM_INF;

- xp->family = family;
+ xp->family = sk->sk_family;

	xp->xfrm_nr = 0;
	if (pol->sadb_x_policy_type == IPSEC_POLICY_IPSEC &&
@@ -2907,8 +2907,10 @@ static struct xfrm_policy *pfkey_compile
		p += pol->sadb_x_policy_len*8;
		sec_ctx = (struct sadb_x_sec_ctx *)p;
		if (len < pol->sadb_x_policy_len*8 +
-		    sec_ctx->sadb_x_sec_len)
+		    sec_ctx->sadb_x_sec_len) {
+			*dir = -EINVAL;
			goto out;
+		}
		if ((*dir = verify_sec_ctx_len(p)))
			goto out;
		uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx);
@@ -2918,6 +2920,11 @@ static struct xfrm_policy *pfkey_compile
		if (*dir)
			goto out;
	}

+ else {
+ *dir = security_xfrm_sock_policy_alloc(xp, sk);
+ if (*dir)
+ goto out;
+ }

	*dir = pol->sadb_x_policy_dir-1;
	return xp;

@@ -1027,7 +1027,7 @@ int xfrm_user_policy(struct sock *sk, in

	err = -EINVAL;
	read_lock(&xfrm_km_lock);
	list_for_each_entry(km, &xfrm_km_list, list) {
-		pol = km->compile_policy(sk->sk_family, optname, data,
+		pol = km->compile_policy(sk, optname, data,
					 optlen, &err);
		if (err >= 0)
			break;

@@ -1756,7 +1756,7 @@ static int xfrm_send_acquire(struct xfrm

/* User gives us xfrm_user_policy_info followed by an array of 0
* or more templates.
*/
-static struct xfrm_policy *xfrm_compile_policy(u16 family, int opt, +static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt,
u8 *data, int len, int *dir)

{
	struct xfrm_userpolicy_info *p = (struct xfrm_userpolicy_info *)data;
@@ -1764,7 +1764,7 @@ static struct xfrm_policy *xfrm_compile_
	struct xfrm_policy *xp;
	int nr;

- switch (family) {

+	switch (sk->sk_family) {
	case AF_INET:
		if (opt != IP_XFRM_POLICY) {
			*dir = -EOPNOTSUPP;
@@ -1806,6 +1806,15 @@ static struct xfrm_policy *xfrm_compile_
	copy_from_user_policy(xp, p);
	copy_templates(xp, ut, nr);

+ if (!xp->security) {
+ int err = security_xfrm_sock_policy_alloc(xp, sk);
+ if (err) {
+ kfree(xp);
+ *dir = err;
+ return NULL;
+ }
+ }
+

	*dir = p->dir;

	return xp;

--
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