[MLSXFRM]: Flow based matching of xfrm policy and state
This implements a seemless mechanism for xfrm policy selection and
state matching based on the flow sid. This also includes the necessary
SELinux enforcement pieces.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/security.h b/include/linux/security.h
index 4d7fb59..2c4921d 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -31,6 +31,7 @@
#include <linux/msg.h>
#include <linux/sched.h>
#include <linux/key.h>
+#include <linux/xfrm.h>
struct ctl_table;
@@ -825,9 +826,8 @@
* used by the XFRM system.
* @sec_ctx contains the security context information being provided by
* the user-level policy update program (e.g., setkey).
- * Allocate a security structure to the xp->security field.
- * The security field is initialized to NULL when the xfrm_policy is
- * allocated.
+ * Allocate a security structure to the xp->security field; the security
+ * field is initialized to NULL when the xfrm_policy is allocated.
* Return 0 if operation was successful (memory to allocate, legal context)
* @xfrm_policy_clone_security:
* @old contains an existing xfrm_policy in the SPD.
@@ -846,9 +846,14 @@
* Database by the XFRM system.
* @sec_ctx contains the security context information being provided by
* the user-level SA generation program (e.g., setkey or racoon).
- * Allocate a security structure to the x->security field. The
- * security field is initialized to NULL when the xfrm_state is
- * allocated.
+ * @polsec contains the security context information associated with a xfrm
+ * policy rule from which to take the base context. polsec must be NULL
+ * when sec_ctx is specified.
+ * @secid contains the secid from which to take the mls portion of the context.
+ * Allocate a security structure to the x->security field; the security
+ * field is initialized to NULL when the xfrm_state is allocated. Set the
+ * context to correspond to either sec_ctx or polsec, with the mls portion
+ * taken from secid in the latter case.
* Return 0 if operation was successful (memory to allocate, legal context).
* @xfrm_state_free_security:
* @x contains the xfrm_state.
@@ -859,13 +864,26 @@
* @xfrm_policy_lookup:
* @xp contains the xfrm_policy for which the access control is being
* checked.
- * @sk_sid contains the sock security label that is used to authorize
+ * @fl_secid contains the flow security label that is used to authorize
* access to the policy xp.
* @dir contains the direction of the flow (input or output).
- * Check permission when a sock selects a xfrm_policy for processing
+ * Check permission when a flow selects a xfrm_policy for processing
* XFRMs on a packet. The hook is called when selecting either a
* per-socket policy or a generic xfrm policy.
* Return 0 if permission is granted.
+ * @xfrm_state_pol_flow_match:
+ * @x contains the state to match.
+ * @xp contains the policy to check for a match.
+ * @fl contains the flow to check for a match.
+ * Return 1 if there is a match.
+ * @xfrm_flow_state_match:
+ * @fl contains the flow key to match.
+ * @xfrm points to the xfrm_state to match.
+ * Return 1 if there is a match.
+ * @xfrm_decode_session:
+ * @skb points to skb to decode.
+ * @fl points to the flow key to set.
+ * Return 0 if successful decoding.
*
* Security hooks affecting all Key Management operations
*
@@ -1343,10 +1361,16 @@
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);
- int (*xfrm_state_alloc_security) (struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx);
+ int (*xfrm_state_alloc_security) (struct xfrm_state *x,
+ struct xfrm_user_sec_ctx *sec_ctx, struct xfrm_sec_ctx *polsec,
+ u32 secid);
void (*xfrm_state_free_security) (struct xfrm_state *x);
int (*xfrm_state_delete_security) (struct xfrm_state *x);
- int (*xfrm_policy_lookup)(struct xfrm_policy *xp, u32 sk_sid, u8 dir);
+ int (*xfrm_policy_lookup)(struct xfrm_policy *xp, u32 fl_secid, u8 dir);
+ int (*xfrm_state_pol_flow_match)(struct xfrm_state *x,
+ struct xfrm_policy *xp, struct flowi *fl);
+ int (*xfrm_flow_state_match)(struct flowi *fl, struct xfrm_state *xfrm);
+ int (*xfrm_decode_session)(struct sk_buff *skb, struct flowi *fl);
#endif /* CONFIG_SECURITY_NETWORK_XFRM */
/* key management security hooks */
@@ -3050,9 +3074,18 @@
return security_ops->xfrm_policy_delete_security(xp);
}
-static inline int security_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx)
+static inline int security_xfrm_state_alloc(struct xfrm_state *x,
+ struct xfrm_user_sec_ctx *sec_ctx)
{
- return security_ops->xfrm_state_alloc_security(x, sec_ctx);
+ return security_ops->xfrm_state_alloc_security(x, sec_ctx, NULL, 0);
+}
+
+static inline int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
+ struct xfrm_sec_ctx *polsec, u32 secid)
+{
+ if (!polsec)
+ return 0;
+ return security_ops->xfrm_state_alloc_security(x, NULL, polsec, secid);
}
static inline int security_xfrm_state_delete(struct xfrm_state *x)
@@ -3065,9 +3098,25 @@
security_ops->xfrm_state_free_security(x);
}
-static inline int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 sk_sid, u8 dir)
+static inline int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir)
{
- return security_ops->xfrm_policy_lookup(xp, sk_sid, dir);
+ return security_ops->xfrm_policy_lookup(xp, fl_secid, dir);
+}
+
+static inline int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
+ struct xfrm_policy *xp, struct flowi *fl)
+{
+ return security_ops->xfrm_state_pol_flow_match(x, xp, fl);
+}
+
+static inline int security_xfrm_flow_state_match(struct flowi *fl, struct xfrm_state *xfrm)
+{
+ return security_ops->xfrm_flow_state_match(fl, xfrm);
+}
+
+static inline int security_xfrm_decode_session(struct sk_buff *skb, struct flowi *fl)
+{
+ return security_ops->xfrm_decode_session(skb, fl);
}
#else /* CONFIG_SECURITY_NETWORK_XFRM */
static inline int security_xfrm_policy_alloc(struct xfrm_policy *xp, struct xfrm_user_sec_ctx *sec_ctx)
@@ -3089,7 +3138,14 @@
return 0;
}
-static inline int security_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx)
+static inline int security_xfrm_state_alloc(struct xfrm_state *x,
+ struct xfrm_user_sec_ctx *sec_ctx)
+{
+ return 0;
+}
+
+static inline int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
+ struct xfrm_sec_ctx *polsec, u32 secid)
{
return 0;
}
@@ -3103,10 +3159,28 @@
return 0;
}
-static inline int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 sk_sid, u8 dir)
+static inline int security_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir)
{
return 0;
}
+
+static inline int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
+ struct xfrm_policy *xp, struct flowi *fl)
+{
+ return 1;
+}
+
+static inline int security_xfrm_flow_state_match(struct flowi *fl,
+ struct xfrm_state *xfrm)
+{
+ return 1;
+}
+
+static inline int security_xfrm_decode_session(struct sk_buff *skb, struct flowi *fl)
+{
+ return 0;
+}
+
#endif /* CONFIG_SECURITY_NETWORK_XFRM */
#ifdef CONFIG_KEYS
diff --git a/include/net/flow.h b/include/net/flow.h
index 1cee5a8..21d988b 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -86,10 +86,10 @@
#define FLOW_DIR_FWD 2
struct sock;
-typedef void (*flow_resolve_t)(struct flowi *key, u32 sk_sid, u16 family, u8 dir,
+typedef void (*flow_resolve_t)(struct flowi *key, u16 family, u8 dir,
void **objp, atomic_t **obj_refp);
-extern void *flow_cache_lookup(struct flowi *key, u32 sk_sid, u16 family, u8 dir,
+extern void *flow_cache_lookup(struct flowi *key, u16 family, u8 dir,
flow_resolve_t resolver);
extern void flow_cache_flush(void);
extern atomic_t flow_cache_genid;
diff --git a/net/core/flow.c b/net/core/flow.c
index 2191af5..6452411 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -32,7 +32,6 @@
u8 dir;
struct flowi key;
u32 genid;
- u32 sk_sid;
void *object;
atomic_t *object_ref;
};
@@ -165,7 +164,7 @@
return 0;
}
-void *flow_cache_lookup(struct flowi *key, u32 sk_sid, u16 family, u8 dir,
+void *flow_cache_lookup(struct flowi *key, u16 family, u8 dir,
flow_resolve_t resolver)
{
struct flow_cache_entry *fle, **head;
@@ -189,7 +188,6 @@
for (fle = *head; fle; fle = fle->next) {
if (fle->family == family &&
fle->dir == dir &&
- fle->sk_sid == sk_sid &&
flow_key_compare(key, &fle->key) == 0) {
if (fle->genid == atomic_read(&flow_cache_genid)) {
void *ret = fle->object;
@@ -214,7 +212,6 @@
*head = fle;
fle->family = family;
fle->dir = dir;
- fle->sk_sid = sk_sid;
memcpy(&fle->key, key, sizeof(*key));
fle->object = NULL;
flow_count(cpu)++;
@@ -226,7 +223,7 @@
void *obj;
atomic_t *obj_ref;
- resolver(key, sk_sid, family, dir, &obj, &obj_ref);
+ resolver(key, family, dir, &obj, &obj_ref);
if (fle) {
fle->genid = atomic_read(&flow_cache_genid);
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 3da67ca..79405da 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -597,7 +597,7 @@
/* Find policy to apply to this flow. */
-static void xfrm_policy_lookup(struct flowi *fl, u32 sk_sid, u16 family, u8 dir,
+static void xfrm_policy_lookup(struct flowi *fl, u16 family, u8 dir,
void **objp, atomic_t **obj_refp)
{
struct xfrm_policy *pol;
@@ -613,7 +613,7 @@
match = xfrm_selector_match(sel, fl, family);
if (match) {
- if (!security_xfrm_policy_lookup(pol, sk_sid, dir)) {
+ if (!security_xfrm_policy_lookup(pol, fl->secid, dir)) {
xfrm_pol_hold(pol);
break;
}
@@ -641,7 +641,7 @@
};
}
-static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl, u32 sk_sid)
+static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
{
struct xfrm_policy *pol;
@@ -652,7 +652,7 @@
int err = 0;
if (match)
- err = security_xfrm_policy_lookup(pol, sk_sid, policy_to_flow_dir(dir));
+ err = security_xfrm_policy_lookup(pol, fl->secid, policy_to_flow_dir(dir));
if (match && !err)
xfrm_pol_hold(pol);
@@ -862,19 +862,20 @@
u32 genid;
u16 family;
u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
- u32 sk_sid = security_sk_sid(sk, fl, dir);
+
+ fl->secid = security_sk_sid(sk, fl, dir);
restart:
genid = atomic_read(&flow_cache_genid);
policy = NULL;
if (sk && sk->sk_policy[1])
- policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, sk_sid);
+ policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
if (!policy) {
/* To accelerate a bit... */
if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT])
return 0;
- policy = flow_cache_lookup(fl, sk_sid, dst_orig->ops->family,
+ policy = flow_cache_lookup(fl, dst_orig->ops->family,
dir, xfrm_policy_lookup);
}
@@ -1032,13 +1033,15 @@
xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family)
{
struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+ int err;
if (unlikely(afinfo == NULL))
return -EAFNOSUPPORT;
afinfo->decode_session(skb, fl);
+ err = security_xfrm_decode_session(skb, fl);
xfrm_policy_put_afinfo(afinfo);
- return 0;
+ return err;
}
EXPORT_SYMBOL(xfrm_decode_session);
@@ -1058,14 +1061,11 @@
struct xfrm_policy *pol;
struct flowi fl;
u8 fl_dir = policy_to_flow_dir(dir);
- u32 sk_sid;
if (xfrm_decode_session(skb, &fl, family) < 0)
return 0;
nf_nat_decode_session(skb, &fl, family);
- sk_sid = security_sk_sid(sk, &fl, fl_dir);
-
/* First, check used SA against their selectors. */
if (skb->sp) {
int i;
@@ -1079,10 +1079,10 @@
pol = NULL;
if (sk && sk->sk_policy[dir])
- pol = xfrm_sk_policy_lookup(sk, dir, &fl, sk_sid);
+ pol = xfrm_sk_policy_lookup(sk, dir, &fl);
if (!pol)
- pol = flow_cache_lookup(&fl, sk_sid, family, fl_dir,
+ pol = flow_cache_lookup(&fl, family, fl_dir,
xfrm_policy_lookup);
if (!pol)
@@ -1298,6 +1298,8 @@
if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
return 0;
+ if (fl && !security_xfrm_flow_state_match(fl, dst->xfrm))
+ return 0;
if (dst->xfrm->km.state != XFRM_STATE_VALID)
return 0;
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 0021aad..be02bd9 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -367,7 +367,7 @@
*/
if (x->km.state == XFRM_STATE_VALID) {
if (!xfrm_selector_match(&x->sel, fl, family) ||
- !xfrm_sec_ctx_match(pol->security, x->security))
+ !security_xfrm_state_pol_flow_match(x, pol, fl))
continue;
if (!best ||
best->km.dying > x->km.dying ||
@@ -379,7 +379,7 @@
} else if (x->km.state == XFRM_STATE_ERROR ||
x->km.state == XFRM_STATE_EXPIRED) {
if (xfrm_selector_match(&x->sel, fl, family) &&
- xfrm_sec_ctx_match(pol->security, x->security))
+ security_xfrm_state_pol_flow_match(x, pol, fl))
error = -ESRCH;
}
}
@@ -403,6 +403,14 @@
* to current session. */
xfrm_init_tempsel(x, fl, tmpl, daddr, saddr, family);
+ error = security_xfrm_state_alloc_acquire(x, pol->security, fl->secid);
+ if (error) {
+ x->km.state = XFRM_STATE_DEAD;
+ xfrm_state_put(x);
+ x = NULL;
+ goto out;
+ }
+
if (km_query(x, tmpl, pol) == 0) {
x->km.state = XFRM_STATE_ACQ;
list_add_tail(&x->bydst, xfrm_state_bydst+h);
diff --git a/security/dummy.c b/security/dummy.c
index bd3bc5f..c1f1065 100644
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -835,7 +835,8 @@
return 0;
}
-static int dummy_xfrm_state_alloc_security(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx)
+static int dummy_xfrm_state_alloc_security(struct xfrm_state *x,
+ struct xfrm_user_sec_ctx *sec_ctx, struct xfrm_sec_ctx *pol, u32 secid)
{
return 0;
}
@@ -853,6 +854,23 @@
{
return 0;
}
+
+static int dummy_xfrm_state_pol_flow_match(struct xfrm_state *x,
+ struct xfrm_policy *xp, struct flowi *fl)
+{
+ return 1;
+}
+
+static int dummy_xfrm_flow_state_match(struct flowi *fl, struct xfrm_state *xfrm)
+{
+ return 1;
+}
+
+static int dummy_xfrm_decode_session(struct sk_buff *skb, struct flowi *fl)
+{
+ return 0;
+}
+
#endif /* CONFIG_SECURITY_NETWORK_XFRM */
static int dummy_register_security (const char *name, struct security_operations *ops)
{
@@ -1076,6 +1094,9 @@
set_to_dummy_if_null(ops, xfrm_state_free_security);
set_to_dummy_if_null(ops, xfrm_state_delete_security);
set_to_dummy_if_null(ops, xfrm_policy_lookup);
+ set_to_dummy_if_null(ops, xfrm_state_pol_flow_match);
+ set_to_dummy_if_null(ops, xfrm_flow_state_match);
+ set_to_dummy_if_null(ops, xfrm_decode_session);
#endif /* CONFIG_SECURITY_NETWORK_XFRM */
#ifdef CONFIG_KEYS
set_to_dummy_if_null(ops, key_alloc);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d67abf7..5c189da 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3468,7 +3468,7 @@
if (err)
goto out;
- err = selinux_xfrm_sock_rcv_skb(sock_sid, skb);
+ err = selinux_xfrm_sock_rcv_skb(sock_sid, skb, &ad);
out:
return err;
}
@@ -3720,7 +3720,7 @@
if (err)
goto out;
- err = selinux_xfrm_postroute_last(isec->sid, skb);
+ err = selinux_xfrm_postroute_last(isec->sid, skb, &ad);
out:
return err ? NF_DROP : NF_ACCEPT;
}
@@ -4633,6 +4633,9 @@
.xfrm_state_free_security = selinux_xfrm_state_free,
.xfrm_state_delete_security = selinux_xfrm_state_delete,
.xfrm_policy_lookup = selinux_xfrm_policy_lookup,
+ .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
+ .xfrm_flow_state_match = selinux_xfrm_flow_state_match,
+ .xfrm_decode_session = selinux_xfrm_decode_session,
#endif
#ifdef CONFIG_KEYS
diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h
index c96498a..f51a3e8 100644
--- a/security/selinux/include/xfrm.h
+++ b/security/selinux/include/xfrm.h
@@ -2,6 +2,7 @@
* SELinux support for the XFRM LSM hooks
*
* Author : Trent Jaeger, <jaegert@us.ibm.com>
+ * Updated : Venkat Yekkirala, <vyekkirala@TrustedCS.com>
*/
#ifndef _SELINUX_XFRM_H_
#define _SELINUX_XFRM_H_
@@ -10,10 +11,16 @@
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);
-int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx);
+int selinux_xfrm_state_alloc(struct xfrm_state *x,
+ struct xfrm_user_sec_ctx *sec_ctx, struct xfrm_sec_ctx *pol, u32 secid);
void selinux_xfrm_state_free(struct xfrm_state *x);
int selinux_xfrm_state_delete(struct xfrm_state *x);
-int selinux_xfrm_policy_lookup(struct xfrm_policy *xp, u32 sk_sid, u8 dir);
+int selinux_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir);
+int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x,
+ struct xfrm_policy *xp, struct flowi *fl);
+int selinux_xfrm_flow_state_match(struct flowi *fl, struct xfrm_state *xfrm);
+int selinux_xfrm_decode_session(struct sk_buff *skb, struct flowi *fl);
+
/*
* Extract the security blob from the sock (it's actually on the socket)
@@ -39,17 +46,21 @@
}
#ifdef CONFIG_SECURITY_NETWORK_XFRM
-int selinux_xfrm_sock_rcv_skb(u32 sid, struct sk_buff *skb);
-int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb);
+int selinux_xfrm_sock_rcv_skb(u32 sid, struct sk_buff *skb,
+ struct avc_audit_data *ad);
+int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb,
+ struct avc_audit_data *ad);
u32 selinux_socket_getpeer_stream(struct sock *sk);
u32 selinux_socket_getpeer_dgram(struct sk_buff *skb);
#else
-static inline int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb)
+static inline int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
+ struct avc_audit_data *ad)
{
return 0;
}
-static inline int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb)
+static inline int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb,
+ struct avc_audit_data *ad)
{
return 0;
}
diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index 6c985ce..a502b05 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -6,7 +6,12 @@
* Authors: Serge Hallyn <sergeh@us.ibm.com>
* Trent Jaeger <jaegert@us.ibm.com>
*
+ * Updated: Venkat Yekkirala <vyekkirala@TrustedCS.com>
+ *
+ * Granular IPSec Associations for use in MLS environments.
+ *
* Copyright (C) 2005 International Business Machines Corporation
+ * Copyright (C) 2006 Trusted Computer Solutions, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2,
@@ -67,10 +72,10 @@
}
/*
- * LSM hook implementation that authorizes that a socket can be used
- * with the corresponding xfrm_sec_ctx and direction.
+ * LSM hook implementation that authorizes that a flow can use
+ * a xfrm policy rule.
*/
-int selinux_xfrm_policy_lookup(struct xfrm_policy *xp, u32 sk_sid, u8 dir)
+int selinux_xfrm_policy_lookup(struct xfrm_policy *xp, u32 fl_secid, u8 dir)
{
int rc = 0;
u32 sel_sid = SECINITSID_UNLABELED;
@@ -84,27 +89,129 @@
sel_sid = ctx->ctx_sid;
}
- rc = avc_has_perm(sk_sid, sel_sid, SECCLASS_ASSOCIATION,
- ((dir == FLOW_DIR_IN) ? ASSOCIATION__RECVFROM :
- ((dir == FLOW_DIR_OUT) ? ASSOCIATION__SENDTO :
- (ASSOCIATION__SENDTO | ASSOCIATION__RECVFROM))),
+ rc = avc_has_perm(fl_secid, sel_sid, SECCLASS_ASSOCIATION,
+ ASSOCIATION__POLMATCH,
NULL);
return rc;
}
/*
+ * LSM hook implementation that authorizes that a state matches
+ * the given policy, flow combo.
+ */
+
+int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x, struct xfrm_policy *xp,
+ struct flowi *fl)
+{
+ u32 state_sid;
+ u32 pol_sid;
+ int err;
+
+ if (x->security)
+ state_sid = x->security->ctx_sid;
+ else
+ state_sid = SECINITSID_UNLABELED;
+
+ if (xp->security)
+ pol_sid = xp->security->ctx_sid;
+ else
+ pol_sid = SECINITSID_UNLABELED;
+
+ err = avc_has_perm(state_sid, pol_sid, SECCLASS_ASSOCIATION,
+ ASSOCIATION__POLMATCH,
+ NULL);
+
+ if (err)
+ return 0;
+
+ return selinux_xfrm_flow_state_match(fl, x);
+}
+
+/*
+ * LSM hook implementation that authorizes that a particular outgoing flow
+ * can use a given security association.
+ */
+
+int selinux_xfrm_flow_state_match(struct flowi *fl, struct xfrm_state *xfrm)
+{
+ int rc = 0;
+ u32 sel_sid = SECINITSID_UNLABELED;
+ struct xfrm_sec_ctx *ctx;
+
+ /* Context sid is either set to label or ANY_ASSOC */
+ if ((ctx = xfrm->security)) {
+ if (!selinux_authorizable_ctx(ctx))
+ return 0;
+
+ sel_sid = ctx->ctx_sid;
+ }
+
+ rc = avc_has_perm(fl->secid, sel_sid, SECCLASS_ASSOCIATION,
+ ASSOCIATION__SENDTO,
+ NULL)? 0:1;
+
+ return rc;
+}
+
+/*
+ * LSM hook implementation that determines the sid for the session.
+ */
+
+int selinux_xfrm_decode_session(struct sk_buff *skb, struct flowi *fl)
+{
+ struct sec_path *sp;
+
+ fl->secid = SECSID_NULL;
+
+ if (skb == NULL)
+ return 0;
+
+ sp = skb->sp;
+ if (sp) {
+ int i, sid_set = 0;
+
+ for (i = sp->len-1; i >= 0; i--) {
+ struct xfrm_state *x = sp->xvec[i];
+ if (selinux_authorizable_xfrm(x)) {
+ struct xfrm_sec_ctx *ctx = x->security;
+
+ if (!sid_set) {
+ fl->secid = ctx->ctx_sid;
+ sid_set = 1;
+ }
+ else if (fl->secid != ctx->ctx_sid)
+ return -EINVAL;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
* Security blob allocation for xfrm_policy and xfrm_state
* CTX does not have a meaningful value on input
*/
-static int selinux_xfrm_sec_ctx_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *uctx)
+static int selinux_xfrm_sec_ctx_alloc(struct xfrm_sec_ctx **ctxp,
+ struct xfrm_user_sec_ctx *uctx, struct xfrm_sec_ctx *pol, u32 sid)
{
int rc = 0;
struct task_security_struct *tsec = current->security;
- struct xfrm_sec_ctx *ctx;
+ struct xfrm_sec_ctx *ctx = NULL;
+ char *ctx_str = NULL;
+ u32 str_len;
+ u32 ctx_sid;
+
+ BUG_ON(uctx && pol);
+
+ if (pol)
+ goto from_policy;
BUG_ON(!uctx);
- BUG_ON(uctx->ctx_doi != XFRM_SC_ALG_SELINUX);
+
+ if (uctx->ctx_doi != XFRM_SC_ALG_SELINUX)
+ return -EINVAL;
if (uctx->ctx_len >= PAGE_SIZE)
return -ENOMEM;
@@ -141,9 +248,41 @@
return rc;
+from_policy:
+ BUG_ON(!pol);
+ rc = security_sid_mls_copy(pol->ctx_sid, sid, &ctx_sid);
+ if (rc)
+ goto out;
+
+ rc = security_sid_to_context(ctx_sid, &ctx_str, &str_len);
+ if (rc)
+ goto out;
+
+ *ctxp = ctx = kmalloc(sizeof(*ctx) +
+ str_len,
+ GFP_ATOMIC);
+
+ if (!ctx) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+
+ ctx->ctx_doi = XFRM_SC_DOI_LSM;
+ ctx->ctx_alg = XFRM_SC_ALG_SELINUX;
+ ctx->ctx_sid = ctx_sid;
+ ctx->ctx_len = str_len;
+ memcpy(ctx->ctx_str,
+ ctx_str,
+ str_len);
+
+ goto out2;
+
out:
*ctxp = NULL;
kfree(ctx);
+out2:
+ kfree(ctx_str);
return rc;
}
@@ -157,7 +296,7 @@
BUG_ON(!xp);
- err = selinux_xfrm_sec_ctx_alloc(&xp->security, uctx);
+ err = selinux_xfrm_sec_ctx_alloc(&xp->security, uctx, NULL, 0);
return err;
}
@@ -217,13 +356,14 @@
* LSM hook implementation that allocs and transfers sec_ctx spec to
* xfrm_state.
*/
-int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *uctx)
+int selinux_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *uctx,
+ struct xfrm_sec_ctx *pol, u32 secid)
{
int err;
BUG_ON(!x);
- err = selinux_xfrm_sec_ctx_alloc(&x->security, uctx);
+ err = selinux_xfrm_sec_ctx_alloc(&x->security, uctx, pol, secid);
return err;
}
@@ -329,38 +469,30 @@
* we need to check for unlabelled access since this may not have
* gone thru the IPSec process.
*/
-int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb)
+int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb,
+ struct avc_audit_data *ad)
{
int i, rc = 0;
struct sec_path *sp;
+ u32 sel_sid = SECINITSID_UNLABELED;
sp = skb->sp;
if (sp) {
- /*
- * __xfrm_policy_check does not approve unless xfrm_policy_ok
- * says that spi's match for policy and the socket.
- *
- * Only need to verify the existence of an authorizable sp.
- */
for (i = 0; i < sp->len; i++) {
struct xfrm_state *x = sp->xvec[i];
- if (x && selinux_authorizable_xfrm(x))
- goto accept;
+ if (x && selinux_authorizable_xfrm(x)) {
+ struct xfrm_sec_ctx *ctx = x->security;
+ sel_sid = ctx->ctx_sid;
+ break;
+ }
}
}
- /* check SELinux sock for unlabelled access */
- rc = avc_has_perm(isec_sid, SECINITSID_UNLABELED, SECCLASS_ASSOCIATION,
- ASSOCIATION__RECVFROM, NULL);
- if (rc)
- goto drop;
+ rc = avc_has_perm(isec_sid, sel_sid, SECCLASS_ASSOCIATION,
+ ASSOCIATION__RECVFROM, ad);
-accept:
- return 0;
-
-drop:
return rc;
}
@@ -371,7 +503,8 @@
* If we do have a authorizable security association, then it has already been
* checked in xfrm_policy_lookup hook.
*/
-int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb)
+int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb,
+ struct avc_audit_data *ad)
{
struct dst_entry *dst;
int rc = 0;
@@ -391,7 +524,7 @@
}
rc = avc_has_perm(isec_sid, SECINITSID_UNLABELED, SECCLASS_ASSOCIATION,
- ASSOCIATION__SENDTO, NULL);
+ ASSOCIATION__SENDTO, ad);
out:
return rc;
}