diff mbox series

[v37,12/33] LSM: Use lsmblob in security_inode_getsecid

Message ID 20220628005611.13106-13-casey@schaufler-ca.com (mailing list archive)
State New
Headers show
Series LSM: Module stacking for AppArmor | expand

Commit Message

Casey Schaufler June 28, 2022, 12:55 a.m. UTC
Change the security_inode_getsecid() interface to fill in a
lsmblob structure instead of a u32 secid. This allows for its
callers to gather data from all registered LSMs. Data is provided
for IMA and audit.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: linux-integrity@vger.kernel.org
Cc: linux-audit@redhat.com
---
 include/linux/security.h            | 13 +++++++------
 kernel/auditsc.c                    |  6 +++++-
 security/integrity/ima/ima_policy.c |  9 +++++----
 security/security.c                 | 19 +++++++++++++------
 4 files changed, 30 insertions(+), 17 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/security.h b/include/linux/security.h
index ce4a4af362f3..a478faa6124e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -476,7 +476,7 @@  int security_inode_getsecurity(struct user_namespace *mnt_userns,
 			       void **buffer, bool alloc);
 int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
 int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
-void security_inode_getsecid(struct inode *inode, u32 *secid);
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob);
 int security_inode_copy_up(struct dentry *src, struct cred **new);
 int security_inode_copy_up_xattr(const char *name);
 int security_kernfs_init_security(struct kernfs_node *kn_dir,
@@ -1022,9 +1022,10 @@  static inline int security_inode_listsecurity(struct inode *inode, char *buffer,
 	return 0;
 }
 
-static inline void security_inode_getsecid(struct inode *inode, u32 *secid)
+static inline void security_inode_getsecid(struct inode *inode,
+					   struct lsmblob *blob)
 {
-	*secid = 0;
+	lsmblob_init(blob, 0);
 }
 
 static inline int security_inode_copy_up(struct dentry *src, struct cred **new)
@@ -2034,8 +2035,8 @@  static inline void security_audit_rule_free(struct audit_lsm_rules *lsmrules)
 #if defined(CONFIG_IMA_LSM_RULES) && defined(CONFIG_SECURITY)
 int ima_filter_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
 			 int lsmslot);
-int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
-			  int lsmslot);
+int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
+			  void *lsmrule, int lsmslot);
 void ima_filter_rule_free(void *lsmrule, int lsmslot);
 
 #else
@@ -2046,7 +2047,7 @@  static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
 	return 0;
 }
 
-static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
+static inline int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
 					void *lsmrule, int lsmslot)
 {
 	return 0;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e5530bbfc83b..1d223176285b 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2306,13 +2306,17 @@  static 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, &name->osid);
+	security_inode_getsecid(inode, &blob);
+	/* scaffolding until osid is updated */
+	name->osid = lsmblob_first(&blob);
 	if (flags & AUDIT_INODE_NOEVAL) {
 		name->fcap_ver = -1;
 		return;
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 5c2bc6782e17..593b0ba51b6e 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -636,7 +636,7 @@  static bool ima_match_rules(struct ima_rule_entry *rule,
 		return false;
 	for (i = 0; i < MAX_LSM_RULES; i++) {
 		int rc = 0;
-		u32 osid;
+		struct lsmblob lsmdata;
 
 		if (!rule->lsm[i].rule) {
 			if (!rule->lsm[i].args_p)
@@ -648,8 +648,9 @@  static bool ima_match_rules(struct ima_rule_entry *rule,
 		case LSM_OBJ_USER:
 		case LSM_OBJ_ROLE:
 		case LSM_OBJ_TYPE:
-			security_inode_getsecid(inode, &osid);
-			rc = ima_filter_rule_match(osid, rule->lsm[i].type,
+			security_inode_getsecid(inode, &lsmdata);
+			rc = ima_filter_rule_match(&lsmdata,
+						   rule->lsm[i].type,
 						   Audit_equal,
 						   rule->lsm[i].rule,
 						   rule->lsm[i].rules_lsm);
@@ -657,7 +658,7 @@  static bool ima_match_rules(struct ima_rule_entry *rule,
 		case LSM_SUBJ_USER:
 		case LSM_SUBJ_ROLE:
 		case LSM_SUBJ_TYPE:
-			rc = ima_filter_rule_match(lsmblob_first(blob),
+			rc = ima_filter_rule_match(blob,
 						   rule->lsm[i].type,
 						   Audit_equal,
 						   rule->lsm[i].rule,
diff --git a/security/security.c b/security/security.c
index 1a4741178944..ad1080e01ba8 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1560,9 +1560,16 @@  int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer
 }
 EXPORT_SYMBOL(security_inode_listsecurity);
 
-void security_inode_getsecid(struct inode *inode, u32 *secid)
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob)
 {
-	call_void_hook(inode_getsecid, inode, secid);
+	struct security_hook_list *hp;
+
+	lsmblob_init(blob, 0);
+	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecid, list) {
+		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+			continue;
+		hp->hook.inode_getsecid(inode, &blob->secid[hp->lsmid->slot]);
+	}
 }
 
 int security_inode_copy_up(struct dentry *src, struct cred **new)
@@ -2804,15 +2811,15 @@  void ima_filter_rule_free(void *lsmrule, int lsmslot)
 	}
 }
 
-int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
-			  int lsmslot)
+int ima_filter_rule_match(struct lsmblob *blob, u32 field, u32 op,
+			  void *lsmrule, int lsmslot)
 {
 	struct security_hook_list *hp;
 
 	hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list)
 		if (hp->lsmid->slot == lsmslot)
-			return hp->hook.audit_rule_match(secid, field, op,
-							 lsmrule);
+			return hp->hook.audit_rule_match(blob->secid[lsmslot],
+							 field, op, lsmrule);
 
 	return 0;
 }