lsm: use lsm_prop in security_inode_getsecid

Change the security_inode_getsecid() interface to fill in a
lsm_prop 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. Change the name to security_inode_getlsmprop().

Cc: linux-integrity@vger.kernel.org
Cc: selinux@vger.kernel.org
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subj line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>

Author: cschaufler

include/linux/lsm_hook_defs.h

@@ -176,7 +176,8 @@ LSM_HOOK(int, -EOPNOTSUPP, inode_setsecurity, struct inode *inode,
 	 const char *name, const void *value, size_t size, int flags)
 LSM_HOOK(int, 0, inode_listsecurity, struct inode *inode, char *buffer,
 	 size_t buffer_size)
-LSM_HOOK(void, LSM_RET_VOID, inode_getsecid, struct inode *inode, u32 *secid)
+LSM_HOOK(void, LSM_RET_VOID, inode_getlsmprop, struct inode *inode,
+	 struct lsm_prop *prop)
 LSM_HOOK(int, 0, inode_copy_up, struct dentry *src, struct cred **new)
 LSM_HOOK(int, -EOPNOTSUPP, inode_copy_up_xattr, struct dentry *src,
 	 const char *name)

include/linux/security.h

@@ -452,7 +452,7 @@ int security_inode_getsecurity(struct mnt_idmap *idmap,
 			       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_getlsmprop(struct inode *inode, struct lsm_prop *prop);
 int security_inode_copy_up(struct dentry *src, struct cred **new);
 int security_inode_copy_up_xattr(struct dentry *src, const char *name);
 int security_inode_setintegrity(const struct inode *inode,
@@ -1076,9 +1076,10 @@ 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_getlsmprop(struct inode *inode,
+					     struct lsm_prop *prop)
 {
-	*secid = 0;
+	lsmprop_init(prop);
 }
 
 static inline int security_inode_copy_up(struct dentry *src, struct cred **new)

kernel/auditsc.c

@@ -2276,13 +2276,17 @@ static void audit_copy_inode(struct audit_names *name,
 			     const struct dentry *dentry,
 			     struct inode *inode, unsigned int flags)
 {
+	struct lsm_prop prop;
+
 	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_getlsmprop(inode, &prop);
+	/* scaffolding */
+	name->osid = prop.scaffold.secid;
 	if (flags & AUDIT_INODE_NOEVAL) {
 		name->fcap_ver = -1;
 		return;

security/integrity/ima/ima_policy.c

@@ -649,8 +649,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
 		case LSM_OBJ_USER:
 		case LSM_OBJ_ROLE:
 		case LSM_OBJ_TYPE:
-			/* scaffolding */
-			security_inode_getsecid(inode, &prop.scaffold.secid);
+			security_inode_getlsmprop(inode, &prop);
 			rc = ima_filter_rule_match(&prop, lsm_rule->lsm[i].type,
 						   Audit_equal,
 						   lsm_rule->lsm[i].rule);

security/security.c

@@ -2724,16 +2724,15 @@ int security_inode_listsecurity(struct inode *inode,
 EXPORT_SYMBOL(security_inode_listsecurity);
 
 /**
- * security_inode_getsecid() - Get an inode's secid
+ * security_inode_getlsmprop() - Get an inode's LSM data
  * @inode: inode
- * @secid: secid to return
+ * @prop: lsm specific information to return
  *
- * Get the secid associated with the node.  In case of failure, @secid will be
- * set to zero.
+ * Get the lsm specific information associated with the node.
  */
-void security_inode_getsecid(struct inode *inode, u32 *secid)
+void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
 {
-	call_void_hook(inode_getsecid, inode, secid);
+	call_void_hook(inode_getlsmprop, inode, prop);
 }
 
 /**

security/selinux/hooks.c

@@ -3503,15 +3503,18 @@ static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t
 	return len;
 }
 
-static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
+static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
 {
 	struct inode_security_struct *isec = inode_security_novalidate(inode);
-	*secid = isec->sid;
+
+	prop->selinux.secid = isec->sid;
+	/* scaffolding */
+	prop->scaffold.secid = isec->sid;
 }
 
 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
 {
-	u32 sid;
+	struct lsm_prop prop;
 	struct task_security_struct *tsec;
 	struct cred *new_creds = *new;
 
@@ -3523,8 +3526,8 @@ static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
 
 	tsec = selinux_cred(new_creds);
 	/* Get label from overlay inode and set it in create_sid */
-	selinux_inode_getsecid(d_inode(src), &sid);
-	tsec->create_sid = sid;
+	selinux_inode_getlsmprop(d_inode(src), &prop);
+	tsec->create_sid = prop.selinux.secid;
 	*new = new_creds;
 	return 0;
 }
@@ -7174,7 +7177,7 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
-	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
+	LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
 	LSM_HOOK_INIT(path_notify, selinux_path_notify),

security/smack/smack_lsm.c

@@ -1649,15 +1649,17 @@ static int smack_inode_listsecurity(struct inode *inode, char *buffer,
 }
 
 /**
- * smack_inode_getsecid - Extract inode's security id
+ * smack_inode_getlsmprop - Extract inode's security id
  * @inode: inode to extract the info from
- * @secid: where result will be saved
+ * @prop: where result will be saved
  */
-static void smack_inode_getsecid(struct inode *inode, u32 *secid)
+static void smack_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
 {
 	struct smack_known *skp = smk_of_inode(inode);
 
-	*secid = skp->smk_secid;
+	prop->smack.skp = skp;
+	/* scaffolding */
+	prop->scaffold.secid = skp->smk_secid;
 }
 
 /*
@@ -5110,7 +5112,7 @@ static struct security_hook_list smack_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
 	LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
 	LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
-	LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
+	LSM_HOOK_INIT(inode_getlsmprop, smack_inode_getlsmprop),
 
 	LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
 	LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),