[v10,22/25] Audit: Include object data for all security modules
diff mbox series

Message ID 20191113000022.5300-23-casey@schaufler-ca.com
State New
Headers show
Series
  • [v10,01/25] LSM: Infrastructure management of the sock security
Related show

Commit Message

Casey Schaufler Nov. 13, 2019, midnight UTC
When there is more than one context displaying security
module extend what goes into the audit record by supplimenting
the "obj=" with an "obj_<lsm>=" for each such security
module.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 kernel/audit.h   |   4 +-
 kernel/auditsc.c | 110 ++++++++++++++++++++++++-----------------------
 2 files changed, 58 insertions(+), 56 deletions(-)

Patch
diff mbox series

diff --git a/kernel/audit.h b/kernel/audit.h
index 29e29c6f4afb..af9a7d1fc069 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -91,7 +91,7 @@  struct audit_names {
 	kuid_t			uid;
 	kgid_t			gid;
 	dev_t			rdev;
-	u32			osid;
+	struct lsmblob		oblob;
 	struct audit_cap_data	fcap;
 	unsigned int		fcap_ver;
 	unsigned char		type;		/* record type */
@@ -165,7 +165,7 @@  struct audit_context {
 			kuid_t			uid;
 			kgid_t			gid;
 			umode_t			mode;
-			u32			osid;
+			struct lsmblob		oblob;
 			int			has_perm;
 			uid_t			perm_uid;
 			gid_t			perm_gid;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 46d7a58babd2..04367c3593e4 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -646,17 +646,15 @@  static int audit_filter_rules(struct task_struct *tsk,
 			if (f->lsm_rule) {
 				/* Find files that match */
 				if (name) {
-					lsmblob_init(&blob, name->osid);
 					result = security_audit_rule_match(
-								&blob,
+								&name->oblob,
 								f->type,
 								f->op,
 								f->lsm_rule);
 				} else if (ctx) {
 					list_for_each_entry(n, &ctx->names_list, list) {
-						lsmblob_init(&blob, n->osid);
 						if (security_audit_rule_match(
-								&blob,
+								&n->oblob,
 								f->type,
 								f->op,
 								f->lsm_rule)) {
@@ -668,8 +666,7 @@  static int audit_filter_rules(struct task_struct *tsk,
 				/* Find ipc objects that match */
 				if (!ctx || ctx->type != AUDIT_IPC)
 					break;
-				lsmblob_init(&blob, ctx->ipc.osid);
-				if (security_audit_rule_match(&blob,
+				if (security_audit_rule_match(&ctx->ipc.oblob,
 							      f->type, f->op,
 							      f->lsm_rule))
 					++result;
@@ -937,13 +934,57 @@  static inline void audit_free_context(struct audit_context *context)
 	kfree(context);
 }
 
+static int audit_log_object_context(struct audit_buffer *ab,
+				    struct lsmblob *blob)
+{
+	struct lsmcontext context;
+	const char *lsm;
+	int i;
+
+	/*
+	 * None of the installed modules have object labels.
+	 */
+	if (security_lsm_slot_name(0) == NULL)
+		return 0;
+
+	if (blob->secid[0] != 0) {
+		if (security_secid_to_secctx(blob, &context, 0)) {
+			audit_log_format(ab, " obj=?");
+			return 1;
+		}
+		audit_log_format(ab, " obj=%s", context.context);
+		security_release_secctx(&context);
+	}
+
+	/*
+	 * Don't do anything more unless there is more than one LSM
+	 * with a security context to report.
+	 */
+	if (security_lsm_slot_name(1) == NULL)
+		return 0;
+
+	for (i = 0; i < LSMBLOB_ENTRIES; i++) {
+		lsm = security_lsm_slot_name(i);
+		if (lsm == NULL)
+			break;
+		if (blob->secid[i] == 0)
+			continue;
+		if (security_secid_to_secctx(blob, &context, i)) {
+			audit_log_format(ab, " obj_%s=?", lsm);
+			continue;
+		}
+		audit_log_format(ab, " obj_%s=%s", lsm, context.context);
+		security_release_secctx(&context);
+	}
+	return 0;
+}
+
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 				 kuid_t auid, kuid_t uid,
 				 unsigned int sessionid,
 				 struct lsmblob *blob, char *comm)
 {
 	struct audit_buffer *ab;
-	struct lsmcontext lsmctx;
 	int rc = 0;
 
 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
@@ -953,15 +994,7 @@  static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", 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, LSMBLOB_FIRST)) {
-			audit_log_format(ab, " obj=(none)");
-			rc = 1;
-		} else {
-			audit_log_format(ab, " obj=%s", lsmctx.context);
-			security_release_secctx(&lsmctx);
-		}
-	}
+	rc = audit_log_object_context(ab, blob);
 	audit_log_format(ab, " ocomm=");
 	audit_log_untrustedstring(ab, comm);
 	audit_log_end(ab);
@@ -1187,26 +1220,14 @@  static void show_special(struct audit_context *context, int *call_panic)
 				context->socketcall.args[i]);
 		break; }
 	case AUDIT_IPC: {
-		u32 osid = context->ipc.osid;
+		struct lsmblob *oblob = & context->ipc.oblob;
 
 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
 				 from_kuid(&init_user_ns, context->ipc.uid),
 				 from_kgid(&init_user_ns, context->ipc.gid),
 				 context->ipc.mode);
-		if (osid) {
-			struct lsmcontext lsmcxt;
-			struct lsmblob blob;
-
-			lsmblob_init(&blob, osid);
-			if (security_secid_to_secctx(&blob, &lsmcxt,
-						     LSMBLOB_FIRST)) {
-				audit_log_format(ab, " osid=%u", osid);
-				*call_panic = 1;
-			} else {
-				audit_log_format(ab, " obj=%s", lsmcxt.context);
-				security_release_secctx(&lsmcxt);
-			}
-		}
+		if (audit_log_object_context(ab, oblob))
+			*call_panic = 1;
 		if (context->ipc.has_perm) {
 			audit_log_end(ab);
 			ab = audit_log_start(context, GFP_KERNEL,
@@ -1347,20 +1368,8 @@  static void audit_log_name(struct audit_context *context, struct audit_names *n,
 				 from_kgid(&init_user_ns, n->gid),
 				 MAJOR(n->rdev),
 				 MINOR(n->rdev));
-	if (n->osid != 0) {
-		struct lsmblob blob;
-		struct lsmcontext lsmctx;
-
-		lsmblob_init(&blob, n->osid);
-		if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) {
-			audit_log_format(ab, " osid=%u", n->osid);
-			if (call_panic)
-				*call_panic = 2;
-		} else {
-			audit_log_format(ab, " obj=%s", lsmctx.context);
-			security_release_secctx(&lsmctx);
-		}
-	}
+	if (audit_log_object_context(ab, &n->oblob) && call_panic)
+		*call_panic = 2;
 
 	/* log the audit_names record type */
 	switch (n->type) {
@@ -1908,17 +1917,13 @@  static inline int audit_copy_fcaps(struct audit_names *name,
 void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
 		      struct inode *inode, unsigned int flags)
 {
-	struct lsmblob blob;
-
 	name->ino   = inode->i_ino;
 	name->dev   = inode->i_sb->s_dev;
 	name->mode  = inode->i_mode;
 	name->uid   = inode->i_uid;
 	name->gid   = inode->i_gid;
 	name->rdev  = inode->i_rdev;
-	security_inode_getsecid(inode, &blob);
-	/* scaffolding until osid is updated */
-	name->osid = blob.secid[0];
+	security_inode_getsecid(inode, &name->oblob);
 	if (flags & AUDIT_INODE_NOEVAL) {
 		name->fcap_ver = -1;
 		return;
@@ -2268,14 +2273,11 @@  void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
 	struct audit_context *context = audit_context();
-	struct lsmblob blob;
 	context->ipc.uid = ipcp->uid;
 	context->ipc.gid = ipcp->gid;
 	context->ipc.mode = ipcp->mode;
 	context->ipc.has_perm = 0;
-	security_ipc_getsecid(ipcp, &blob);
-	/* scaffolding on the [0] - change "osid" to a lsmblob */
-	context->ipc.osid = blob.secid[0];
+	security_ipc_getsecid(ipcp, &context->ipc.oblob);
 	context->type = AUDIT_IPC;
 }