public inbox for linux-audit@redhat.com
 help / color / mirror / Atom feed
From: Casey Schaufler <casey@schaufler-ca.com>
To: casey.schaufler@intel.com, jmorris@namei.org,
	linux-security-module@vger.kernel.org, selinux@vger.kernel.org
Cc: john.johansen@canonical.com, linux-kernel@vger.kernel.org,
	linux-audit@redhat.com, sds@tycho.nsa.gov
Subject: [PATCH v30 21/28] LSM: Extend security_secid_to_secctx to include module selection
Date: Tue, 23 Nov 2021 17:43:25 -0800	[thread overview]
Message-ID: <20211124014332.36128-22-casey@schaufler-ca.com> (raw)
In-Reply-To: <20211124014332.36128-1-casey@schaufler-ca.com>

Add a parameter to security_secid_to_secctx() to identify
which of the security modules that may be active should
provide the security context. If the parameter is greater
than or equal to zero, the security module associated with
that LSM "slot" is used. If the value is LSMBLOB_DISPLAY
the "interface lsm" is used. If the value is LSMBLOB_FIRST
the first security module providing a hook is used.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 drivers/android/binder.c                |  2 +-
 include/linux/security.h                |  7 +++++--
 include/net/scm.h                       |  2 +-
 kernel/audit.c                          |  4 ++--
 kernel/auditsc.c                        |  7 ++++---
 net/ipv4/ip_sockglue.c                  |  2 +-
 net/netfilter/nf_conntrack_netlink.c    |  4 ++--
 net/netfilter/nf_conntrack_standalone.c |  2 +-
 net/netfilter/nfnetlink_queue.c         |  2 +-
 net/netlabel/netlabel_unlabeled.c       | 11 +++++++----
 net/netlabel/netlabel_user.c            |  2 +-
 security/security.c                     | 19 +++++++++++++++++--
 12 files changed, 43 insertions(+), 21 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 7172d864579d..38987c68f4d5 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2721,7 +2721,7 @@ static void binder_transaction(struct binder_proc *proc,
 		size_t added_size;
 
 		security_cred_getsecid(proc->cred, &blob);
-		ret = security_secid_to_secctx(&blob, &lsmctx);
+		ret = security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_DISPLAY);
 		if (ret) {
 			return_error = BR_FAILED_REPLY;
 			return_error_param = ret;
diff --git a/include/linux/security.h b/include/linux/security.h
index a35618740b19..763dca314c00 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -184,6 +184,8 @@ struct lsmblob {
 #define LSMBLOB_INVALID		-1	/* Not a valid LSM slot number */
 #define LSMBLOB_NEEDED		-2	/* Slot requested on initialization */
 #define LSMBLOB_NOT_NEEDED	-3	/* Slot not requested */
+#define LSMBLOB_DISPLAY		-4	/* Use the "interface_lsm" slot */
+#define LSMBLOB_FIRST		-5	/* Use the first slot */
 
 /**
  * lsmblob_init - initialize an lsmblob structure
@@ -598,7 +600,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
 			 size_t size);
 int security_netlink_send(struct sock *sk, struct sk_buff *skb);
 int security_ismaclabel(const char *name);
-int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp);
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+			     int ilsm);
 int security_secctx_to_secid(const char *secdata, u32 seclen,
 			     struct lsmblob *blob);
 void security_release_secctx(struct lsmcontext *cp);
@@ -1459,7 +1462,7 @@ static inline int security_ismaclabel(const char *name)
 }
 
 static inline int security_secid_to_secctx(struct lsmblob *blob,
-					   struct lsmcontext *cp)
+					   struct lsmcontext *cp, int ilsm)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/include/net/scm.h b/include/net/scm.h
index b77a52f93389..f4d567d4885e 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -101,7 +101,7 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
 		 * and the infrastructure will know which it is.
 		 */
 		lsmblob_init(&lb, scm->secid);
-		err = security_secid_to_secctx(&lb, &context);
+		err = security_secid_to_secctx(&lb, &context, LSMBLOB_DISPLAY);
 
 		if (!err) {
 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, context.len,
diff --git a/kernel/audit.c b/kernel/audit.c
index 841123390d41..3c6e88a9ff62 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1443,7 +1443,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 
 		if (lsmblob_is_set(&audit_sig_lsm)) {
 			err = security_secid_to_secctx(&audit_sig_lsm,
-						       &context);
+						       &context, LSMBLOB_FIRST);
 			if (err)
 				return err;
 		}
@@ -2138,7 +2138,7 @@ int audit_log_task_context(struct audit_buffer *ab)
 	if (!lsmblob_is_set(&blob))
 		return 0;
 
-	error = security_secid_to_secctx(&blob, &context);
+	error = security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST);
 	if (error) {
 		if (error != -EINVAL)
 			goto error_path;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index bdb368382e5d..ded4e8740fa2 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1123,7 +1123,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
 	if (lsmblob_is_set(blob)) {
-		if (security_secid_to_secctx(blob, &lsmctx)) {
+		if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) {
 			audit_log_format(ab, " obj=(none)");
 			rc = 1;
 		} else {
@@ -1369,7 +1369,8 @@ static void show_special(struct audit_context *context, int *call_panic)
 			struct lsmblob blob;
 
 			lsmblob_init(&blob, osid);
-			if (security_secid_to_secctx(&blob, &lsmcxt)) {
+			if (security_secid_to_secctx(&blob, &lsmcxt,
+						     LSMBLOB_FIRST)) {
 				audit_log_format(ab, " osid=%u", osid);
 				*call_panic = 1;
 			} else {
@@ -1532,7 +1533,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 		struct lsmcontext lsmctx;
 
 		lsmblob_init(&blob, n->osid);
-		if (security_secid_to_secctx(&blob, &lsmctx)) {
+		if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) {
 			audit_log_format(ab, " osid=%u", n->osid);
 			if (call_panic)
 				*call_panic = 2;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 47d1085e037e..ebbde7d9d8bc 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -140,7 +140,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 		return;
 
 	lsmblob_init(&lb, secid);
-	err = security_secid_to_secctx(&lb, &context);
+	err = security_secid_to_secctx(&lb, &context, LSMBLOB_DISPLAY);
 	if (err)
 		return;
 
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 0c3e1a8aaf2b..dc31f7a68d6d 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -347,7 +347,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 	 * security_secid_to_secctx() will know which security module
 	 * to use to create the secctx.  */
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return 0;
 
@@ -658,7 +658,7 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
 	struct lsmblob blob;
 	struct lsmcontext context;
 
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return 0;
 
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index c8825e89a21e..541a49d5be9d 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -180,7 +180,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return;
 
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 69343275c54b..ea43bfd14544 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -316,7 +316,7 @@ static void nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
 		 * blob. security_secid_to_secctx() will know which security
 		 * module to use to create the secctx.  */
 		lsmblob_init(&blob, skb->secmark);
-		security_secid_to_secctx(&blob, context);
+		security_secid_to_secctx(&blob, context, LSMBLOB_DISPLAY);
 	}
 
 	read_unlock_bh(&skb->sk->sk_callback_lock);
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 60e36324568f..a70269367827 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -437,7 +437,8 @@ int netlbl_unlhsh_add(struct net *net,
 unlhsh_add_return:
 	rcu_read_unlock();
 	if (audit_buf != NULL) {
-		if (security_secid_to_secctx(lsmblob, &context) == 0) {
+		if (security_secid_to_secctx(lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -491,7 +492,8 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 					  addr->s_addr, mask->s_addr);
 		dev_put(dev);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -550,7 +552,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 					  addr, mask);
 		dev_put(dev);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -1120,7 +1123,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 		lsmb = (struct lsmblob *)&addr6->lsmblob;
 	}
 
-	ret_val = security_secid_to_secctx(lsmb, &context);
+	ret_val = security_secid_to_secctx(lsmb, &context, LSMBLOB_FIRST);
 	if (ret_val != 0)
 		goto list_cb_failure;
 	ret_val = nla_put(cb_arg->skb,
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 951ba0639d20..1941877fd16f 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -100,7 +100,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 
 	lsmblob_init(&blob, audit_info->secid);
 	if (audit_info->secid != 0 &&
-	    security_secid_to_secctx(&blob, &context) == 0) {
+	    security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST) == 0) {
 		audit_log_format(audit_buf, " subj=%s", context.context);
 		security_release_secctx(&context);
 	}
diff --git a/security/security.c b/security/security.c
index e776f71d126c..1d28d25d0ade 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2327,13 +2327,28 @@ int security_ismaclabel(const char *name)
 }
 EXPORT_SYMBOL(security_ismaclabel);
 
-int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+			     int ilsm)
 {
 	struct security_hook_list *hp;
-	int ilsm = lsm_task_ilsm(current);
 
 	memset(cp, 0, sizeof(*cp));
 
+	/*
+	 * ilsm either is the slot number use for formatting
+	 * or an instruction on which relative slot to use.
+	 */
+	if (ilsm == LSMBLOB_DISPLAY)
+		ilsm = lsm_task_ilsm(current);
+	else if (ilsm == LSMBLOB_FIRST)
+		ilsm = LSMBLOB_INVALID;
+	else if (ilsm < 0) {
+		WARN_ONCE(true, "LSM: %s unknown interface LSM\n", __func__);
+		ilsm = LSMBLOB_INVALID;
+	} else if (ilsm >= lsm_slot) {
+		WARN_ONCE(true, "LSM: %s invalid interface LSM\n", __func__);
+		ilsm = LSMBLOB_INVALID;
+	}
 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
 		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
 			continue;
-- 
2.31.1

--
Linux-audit mailing list
Linux-audit@redhat.com
https://listman.redhat.com/mailman/listinfo/linux-audit


  parent reply	other threads:[~2021-11-24  2:06 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20211124014332.36128-1-casey.ref@schaufler-ca.com>
2021-11-24  1:43 ` [PATCH v30 00/28] LSM: Module stacking for AppArmor Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 01/28] integrity: disassociate ima_filter_rule from security_audit_rule Casey Schaufler
2021-12-06  2:43     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 02/28] LSM: Infrastructure management of the sock security Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 03/28] LSM: Add the lsmblob data structure Casey Schaufler
2021-12-06  2:44     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 04/28] LSM: provide lsm name and id slot mappings Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 05/28] IMA: avoid label collisions with stacked LSMs Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 06/28] LSM: Use lsmblob in security_audit_rule_match Casey Schaufler
2021-11-24 13:19     ` kernel test robot
2021-12-06  2:44     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 07/28] LSM: Use lsmblob in security_kernel_act_as Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 08/28] LSM: Use lsmblob in security_secctx_to_secid Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 09/28] LSM: Use lsmblob in security_secid_to_secctx Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 10/28] LSM: Use lsmblob in security_ipc_getsecid Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 11/28] LSM: Use lsmblob in security_task_getsecid Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 12/28] LSM: Use lsmblob in security_inode_getsecid Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 13/28] LSM: Use lsmblob in security_cred_getsecid Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 14/28] LSM: Specify which LSM to display Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 15/28] LSM: Ensure the correct LSM context releaser Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 16/28] LSM: Use lsmcontext in security_secid_to_secctx Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 17/28] LSM: Use lsmcontext in security_inode_getsecctx Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 18/28] LSM: security_secid_to_secctx in netlink netfilter Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 19/28] NET: Store LSM netlabel data in a lsmblob Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 20/28] binder: Pass LSM identifier for confirmation Casey Schaufler
2021-11-24  1:43   ` Casey Schaufler [this message]
2021-11-24  1:43   ` [PATCH v30 22/28] Audit: Keep multiple LSM data in audit_names Casey Schaufler
2021-12-06  2:44     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 23/28] Audit: Create audit_stamp structure Casey Schaufler
2021-12-06  2:44     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 24/28] Audit: Add framework for auxiliary records Casey Schaufler
2021-12-06  2:45     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 25/28] Audit: Add record for multiple task security contexts Casey Schaufler
2021-12-06  2:45     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 26/28] Audit: Add record for multiple object " Casey Schaufler
2021-11-24  7:41     ` kernel test robot
2021-11-24 13:40     ` kernel test robot
2021-12-06  2:45     ` Paul Moore
2021-11-24  1:43   ` [PATCH v30 27/28] LSM: Add /proc attr entry for full LSM context Casey Schaufler
2021-11-24  1:43   ` [PATCH v30 28/28] AppArmor: Remove the exclusive flag Casey Schaufler

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211124014332.36128-22-casey@schaufler-ca.com \
    --to=casey@schaufler-ca.com \
    --cc=casey.schaufler@intel.com \
    --cc=jmorris@namei.org \
    --cc=john.johansen@canonical.com \
    --cc=linux-audit@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=sds@tycho.nsa.gov \
    --cc=selinux@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox