Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next

Author: James Morris

Documentation/ABI/testing/ima_policy

@@ -20,17 +20,19 @@ Description:
 		action: measure | dont_measure | appraise | dont_appraise | audit
 		condition:= base | lsm  [option]
 			base:	[[func=] [mask=] [fsmagic=] [fsuuid=] [uid=]
-				 [fowner]]
+				[euid=] [fowner=]]
 			lsm:	[[subj_user=] [subj_role=] [subj_type=]
 				 [obj_user=] [obj_role=] [obj_type=]]
 			option:	[[appraise_type=]] [permit_directio]
 
 		base: 	func:= [BPRM_CHECK][MMAP_CHECK][FILE_CHECK][MODULE_CHECK]
 				[FIRMWARE_CHECK]
-			mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC]
+			mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
+			       [[^]MAY_EXEC]
 			fsmagic:= hex value
 			fsuuid:= file system UUID (e.g 8bcbe394-4f13-4144-be8e-5aa9ea2ce2f6)
 			uid:= decimal value
+			euid:= decimal value
 			fowner:=decimal value
 		lsm:  	are LSM specific
 		option:	appraise_type:= [imasig]

Documentation/kernel-parameters.txt

@@ -1398,7 +1398,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			The list of supported hash algorithms is defined
 			in crypto/hash_info.h.
 
-	ima_tcb		[IMA]
+	ima_policy=	[IMA]
+			The builtin measurement policy to load during IMA
+			setup.  Specyfing "tcb" as the value, measures all
+			programs exec'd, files mmap'd for exec, and all files
+			opened with the read mode bit set by either the
+			effective uid (euid=0) or uid=0.
+			Format: "tcb"
+
+	ima_tcb		[IMA] Deprecated.  Use ima_policy= instead.
 			Load a policy which meets the needs of the Trusted
 			Computing Base.  This means IMA will measure all
 			programs exec'd, files mmap'd for exec, and all files

security/integrity/ima/ima.h

@@ -115,7 +115,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
 		       const char *op, const char *cause);
 int ima_init_crypto(void);
 void ima_putc(struct seq_file *m, void *data, int datalen);
-void ima_print_digest(struct seq_file *m, u8 *digest, int size);
+void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
 struct ima_template_desc *ima_template_desc_current(void);
 int ima_init_template(void);
 

security/integrity/ima/ima_fs.c

@@ -190,9 +190,9 @@ static const struct file_operations ima_measurements_ops = {
 	.release = seq_release,
 };
 
-void ima_print_digest(struct seq_file *m, u8 *digest, int size)
+void ima_print_digest(struct seq_file *m, u8 *digest, u32 size)
 {
-	int i;
+	u32 i;
 
 	for (i = 0; i < size; i++)
 		seq_printf(m, "%02x", *(digest + i));

security/integrity/ima/ima_policy.c

@@ -27,6 +27,8 @@
 #define IMA_UID		0x0008
 #define IMA_FOWNER	0x0010
 #define IMA_FSUUID	0x0020
+#define IMA_INMASK	0x0040
+#define IMA_EUID	0x0080
 
 #define UNKNOWN		0
 #define MEASURE		0x0001	/* same as IMA_MEASURE */
@@ -42,6 +44,8 @@ enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
 	LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
 };
 
+enum policy_types { ORIGINAL_TCB = 1, DEFAULT_TCB };
+
 struct ima_rule_entry {
 	struct list_head list;
 	int action;
@@ -70,7 +74,7 @@ struct ima_rule_entry {
  * normal users can easily run the machine out of memory simply building
  * and running executables.
  */
-static struct ima_rule_entry default_rules[] = {
+static struct ima_rule_entry dont_measure_rules[] = {
 	{.action = DONT_MEASURE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_MEASURE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_MEASURE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
@@ -81,13 +85,29 @@ static struct ima_rule_entry default_rules[] = {
 	{.action = DONT_MEASURE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
 	{.action = DONT_MEASURE, .fsmagic = CGROUP_SUPER_MAGIC,
 	 .flags = IMA_FSMAGIC},
-	{.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
+	{.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC}
+};
+
+static struct ima_rule_entry original_measurement_rules[] = {
 	{.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
 	 .flags = IMA_FUNC | IMA_MASK},
 	{.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
 	 .flags = IMA_FUNC | IMA_MASK},
-	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ, .uid = GLOBAL_ROOT_UID,
-	 .flags = IMA_FUNC | IMA_MASK | IMA_UID},
+	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+	 .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_MASK | IMA_UID},
+	{.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
+	{.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
+};
+
+static struct ima_rule_entry default_measurement_rules[] = {
+	{.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
+	 .flags = IMA_FUNC | IMA_MASK},
+	{.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
+	 .flags = IMA_FUNC | IMA_MASK},
+	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+	 .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_INMASK | IMA_EUID},
+	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
+	 .uid = GLOBAL_ROOT_UID, .flags = IMA_FUNC | IMA_INMASK | IMA_UID},
 	{.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
 	{.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
 };
@@ -119,14 +139,29 @@ static struct list_head *ima_rules;
 
 static DEFINE_MUTEX(ima_rules_mutex);
 
-static bool ima_use_tcb __initdata;
+static int ima_policy __initdata;
 static int __init default_measure_policy_setup(char *str)
 {
-	ima_use_tcb = 1;
+	if (ima_policy)
+		return 1;
+
+	ima_policy = ORIGINAL_TCB;
 	return 1;
 }
 __setup("ima_tcb", default_measure_policy_setup);
 
+static int __init policy_setup(char *str)
+{
+	if (ima_policy)
+		return 1;
+
+	if (strcmp(str, "tcb") == 0)
+		ima_policy = DEFAULT_TCB;
+
+	return 1;
+}
+__setup("ima_policy=", policy_setup);
+
 static bool ima_use_appraise_tcb __initdata;
 static int __init default_appraise_policy_setup(char *str)
 {
@@ -186,6 +221,9 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
 	if ((rule->flags & IMA_MASK) &&
 	    (rule->mask != mask && func != POST_SETATTR))
 		return false;
+	if ((rule->flags & IMA_INMASK) &&
+	    (!(rule->mask & mask) && func != POST_SETATTR))
+		return false;
 	if ((rule->flags & IMA_FSMAGIC)
 	    && rule->fsmagic != inode->i_sb->s_magic)
 		return false;
@@ -194,6 +232,16 @@ static bool ima_match_rules(struct ima_rule_entry *rule,
 		return false;
 	if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
 		return false;
+	if (rule->flags & IMA_EUID) {
+		if (has_capability_noaudit(current, CAP_SETUID)) {
+			if (!uid_eq(rule->uid, cred->euid)
+			    && !uid_eq(rule->uid, cred->suid)
+			    && !uid_eq(rule->uid, cred->uid))
+				return false;
+		} else if (!uid_eq(rule->uid, cred->euid))
+			return false;
+	}
+
 	if ((rule->flags & IMA_FOWNER) && !uid_eq(rule->fowner, inode->i_uid))
 		return false;
 	for (i = 0; i < MAX_LSM_RULES; i++) {
@@ -337,13 +385,27 @@ void __init ima_init_policy(void)
 {
 	int i, measure_entries, appraise_entries;
 
-	/* if !ima_use_tcb set entries = 0 so we load NO default rules */
-	measure_entries = ima_use_tcb ? ARRAY_SIZE(default_rules) : 0;
+	/* if !ima_policy set entries = 0 so we load NO default rules */
+	measure_entries = ima_policy ? ARRAY_SIZE(dont_measure_rules) : 0;
 	appraise_entries = ima_use_appraise_tcb ?
 			 ARRAY_SIZE(default_appraise_rules) : 0;
 
 	for (i = 0; i < measure_entries; i++)
-		list_add_tail(&default_rules[i].list, &ima_default_rules);
+		list_add_tail(&dont_measure_rules[i].list, &ima_default_rules);
+
+	switch (ima_policy) {
+	case ORIGINAL_TCB:
+		for (i = 0; i < ARRAY_SIZE(original_measurement_rules); i++)
+			list_add_tail(&original_measurement_rules[i].list,
+				      &ima_default_rules);
+		break;
+	case DEFAULT_TCB:
+		for (i = 0; i < ARRAY_SIZE(default_measurement_rules); i++)
+			list_add_tail(&default_measurement_rules[i].list,
+				      &ima_default_rules);
+	default:
+		break;
+	}
 
 	for (i = 0; i < appraise_entries; i++) {
 		list_add_tail(&default_appraise_rules[i].list,
@@ -373,7 +435,8 @@ enum {
 	Opt_audit,
 	Opt_obj_user, Opt_obj_role, Opt_obj_type,
 	Opt_subj_user, Opt_subj_role, Opt_subj_type,
-	Opt_func, Opt_mask, Opt_fsmagic, Opt_uid, Opt_fowner,
+	Opt_func, Opt_mask, Opt_fsmagic,
+	Opt_uid, Opt_euid, Opt_fowner,
 	Opt_appraise_type, Opt_fsuuid, Opt_permit_directio
 };
 
@@ -394,6 +457,7 @@ static match_table_t policy_tokens = {
 	{Opt_fsmagic, "fsmagic=%s"},
 	{Opt_fsuuid, "fsuuid=%s"},
 	{Opt_uid, "uid=%s"},
+	{Opt_euid, "euid=%s"},
 	{Opt_fowner, "fowner=%s"},
 	{Opt_appraise_type, "appraise_type=%s"},
 	{Opt_permit_directio, "permit_directio"},
@@ -435,6 +499,7 @@ static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
 static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 {
 	struct audit_buffer *ab;
+	char *from;
 	char *p;
 	int result = 0;
 
@@ -525,18 +590,23 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 			if (entry->mask)
 				result = -EINVAL;
 
-			if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
+			from = args[0].from;
+			if (*from == '^')
+				from++;
+
+			if ((strcmp(from, "MAY_EXEC")) == 0)
 				entry->mask = MAY_EXEC;
-			else if (strcmp(args[0].from, "MAY_WRITE") == 0)
+			else if (strcmp(from, "MAY_WRITE") == 0)
 				entry->mask = MAY_WRITE;
-			else if (strcmp(args[0].from, "MAY_READ") == 0)
+			else if (strcmp(from, "MAY_READ") == 0)
 				entry->mask = MAY_READ;
-			else if (strcmp(args[0].from, "MAY_APPEND") == 0)
+			else if (strcmp(from, "MAY_APPEND") == 0)
 				entry->mask = MAY_APPEND;
 			else
 				result = -EINVAL;
 			if (!result)
-				entry->flags |= IMA_MASK;
+				entry->flags |= (*args[0].from == '^')
+				     ? IMA_INMASK : IMA_MASK;
 			break;
 		case Opt_fsmagic:
 			ima_log_string(ab, "fsmagic", args[0].from);
@@ -566,6 +636,9 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 			break;
 		case Opt_uid:
 			ima_log_string(ab, "uid", args[0].from);
+		case Opt_euid:
+			if (token == Opt_euid)
+				ima_log_string(ab, "euid", args[0].from);
 
 			if (uid_valid(entry->uid)) {
 				result = -EINVAL;
@@ -574,11 +647,14 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 
 			result = kstrtoul(args[0].from, 10, &lnum);
 			if (!result) {
-				entry->uid = make_kuid(current_user_ns(), (uid_t)lnum);
-				if (!uid_valid(entry->uid) || (((uid_t)lnum) != lnum))
+				entry->uid = make_kuid(current_user_ns(),
+						       (uid_t) lnum);
+				if (!uid_valid(entry->uid) ||
+				    (uid_t)lnum != lnum)
 					result = -EINVAL;
 				else
-					entry->flags |= IMA_UID;
+					entry->flags |= (token == Opt_uid)
+					    ? IMA_UID : IMA_EUID;
 			}
 			break;
 		case Opt_fowner:

security/integrity/ima/ima_template_lib.c

@@ -70,7 +70,8 @@ static void ima_show_template_data_ascii(struct seq_file *m,
 					 enum data_formats datafmt,
 					 struct ima_field_data *field_data)
 {
-	u8 *buf_ptr = field_data->data, buflen = field_data->len;
+	u8 *buf_ptr = field_data->data;
+	u32 buflen = field_data->len;
 
 	switch (datafmt) {
 	case DATA_FMT_DIGEST_WITH_ALGO: