Merge tag 'integrity-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity subsystem updates from Mimi Zohar:
"Except for extending the 'encrypted' key type to support user provided
data, the rest is code cleanup, __setup() usage bug fix, and a trivial
change"

* tag 'integrity-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
MAINTAINERS: add missing security/integrity/platform_certs
EVM: fix the evm= __setup handler return value
KEYS: encrypted: Instantiate key with user-provided decrypted data
ima: define ima_max_digest_data struct without a flexible array variable
ima: rename IMA_ACTION_FLAGS to IMA_NONACTION_FLAGS
ima: Return error code obtained from securityfs functions
MAINTAINERS: add missing "security/integrity" directory
ima: Fix trivial typos in the comments

Documentation/security/keys/trusted-encrypted.rst

···
 --------------
 
 Encrypted keys do not depend on a trust source, and are faster, as they use AES
-for encryption/decryption. New keys are created from kernel-generated random
-numbers, and are encrypted/decrypted using a specified ‘master’ key. The
-‘master’ key can either be a trusted-key or user-key type. The main disadvantage
-of encrypted keys is that if they are not rooted in a trusted key, they are only
-as secure as the user key encrypting them. The master user key should therefore
-be loaded in as secure a way as possible, preferably early in boot.
+for encryption/decryption. New keys are created either from kernel-generated
+random numbers or user-provided decrypted data, and are encrypted/decrypted
+using a specified ‘master’ key. The ‘master’ key can either be a trusted-key or
+user-key type. The main disadvantage of encrypted keys is that if they are not
+rooted in a trusted key, they are only as secure as the user key encrypting
+them. The master user key should therefore be loaded in as secure a way as
+possible, preferably early in boot.
 
 
 Usage
···
 
     keyctl add encrypted name "new [format] key-type:master-key-name keylen"
         ring
+    keyctl add encrypted name "new [format] key-type:master-key-name keylen
+        decrypted-data" ring
     keyctl add encrypted name "load hex_blob" ring
     keyctl update keyid "update key-type:master-key-name"
 
···
     default trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b3
     82dbbc55be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e0
     24717c64 5972dcb82ab2dde83376d82b2e3c09ffc
+
+Instantiate an encrypted key "evm" using user-provided decrypted data::
+
+    $ keyctl add encrypted evm "new default user:kmk 32 `cat evm_decrypted_data.blob`" @u
+    794890253
+
+    $ keyctl print 794890253
+    default user:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382d
+    bbc55be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e0247
+    17c64 5972dcb82ab2dde83376d82b2e3c09ffc
 
 Other uses for trusted and encrypted keys, such as for disk and file encryption
 are anticipated.  In particular the new format 'ecryptfs' has been defined

MAINTAINERS

···
 M:	Mimi Zohar <[e-mail]>
 L:	[e-mail]
 S:	Supported
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
 F:	security/integrity/evm/
+F:	security/integrity/
 
 EXTENSIBLE FIRMWARE INTERFACE (EFI)
 M:	Ard Biesheuvel <[e-mail]>
···
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
 F:	security/integrity/ima/
+F:	security/integrity/
 
 INTEL 810/815 FRAMEBUFFER DRIVER
 M:	Antonino Daplas <[e-mail]>
···
 F:	include/linux/keyctl.h
 F:	include/uapi/linux/keyctl.h
 F:	security/keys/
+
+KEYS/KEYRINGS_INTEGRITY
+M:	Jarkko Sakkinen <[e-mail]>
+M:	Mimi Zohar <[e-mail]>
+L:	[e-mail]
+L:	[e-mail]
+S:	Supported
+F:	security/integrity/platform_certs
 
 KFENCE
 M:	Alexander Potapenko <[e-mail]>

security/integrity/evm/evm_main.c

···
 	else
 		pr_err("invalid \"%s\" mode", str);
 
-	return 0;
+	return 1;
 }
 __setup("evm=", evm_set_fixmode);
 

security/integrity/ima/ima_api.c

···
 	const char *audit_cause = "failed";
 	struct inode *inode = file_inode(file);
 	const char *filename = file->f_path.dentry->d_name.name;
+	struct ima_max_digest_data hash;
 	int result = 0;
 	int length;
 	void *tmpbuf;
 	u64 i_version;
-	struct {
-		struct ima_digest_data hdr;
-		char digest[IMA_MAX_DIGEST_SIZE];
-	} hash;
 
 	/*
 	 * Always collect the modsig, because IMA might have already collected
···
 		goto out;
 
 	/*
-	 * Dectecting file change is based on i_version. On filesystems
-	 * which do not support i_version, support is limited to an initial
-	 * measurement/appraisal/audit.
+	 * Detecting file change is based on i_version. On filesystems
+	 * which do not support i_version, support was originally limited
+	 * to an initial measurement/appraisal/audit, but was modified to
+	 * assume the file changed.
 	 */
 	i_version = inode_query_iversion(inode);
 	hash.hdr.algo = algo;

security/integrity/ima/ima_fs.c

···
 
 int __init ima_fs_init(void)
 {
+	int ret;
+
 	ima_dir = securityfs_create_dir("ima", integrity_dir);
 	if (IS_ERR(ima_dir))
-		return -1;
+		return PTR_ERR(ima_dir);
 
 	ima_symlink = securityfs_create_symlink("ima", NULL, "integrity/ima",
 						NULL);
-	if (IS_ERR(ima_symlink))
+	if (IS_ERR(ima_symlink)) {
+		ret = PTR_ERR(ima_symlink);
 		goto out;
+	}
 
 	binary_runtime_measurements =
 	    securityfs_create_file("binary_runtime_measurements",
 				   S_IRUSR | S_IRGRP, ima_dir, NULL,
 				   &ima_measurements_ops);
-	if (IS_ERR(binary_runtime_measurements))
+	if (IS_ERR(binary_runtime_measurements)) {
+		ret = PTR_ERR(binary_runtime_measurements);
 		goto out;
+	}
 
 	ascii_runtime_measurements =
 	    securityfs_create_file("ascii_runtime_measurements",
 				   S_IRUSR | S_IRGRP, ima_dir, NULL,
 				   &ima_ascii_measurements_ops);
-	if (IS_ERR(ascii_runtime_measurements))
+	if (IS_ERR(ascii_runtime_measurements)) {
+		ret = PTR_ERR(ascii_runtime_measurements);
 		goto out;
+	}
 
 	runtime_measurements_count =
 	    securityfs_create_file("runtime_measurements_count",
 				   S_IRUSR | S_IRGRP, ima_dir, NULL,
 				   &ima_measurements_count_ops);
-	if (IS_ERR(runtime_measurements_count))
+	if (IS_ERR(runtime_measurements_count)) {
+		ret = PTR_ERR(runtime_measurements_count);
 		goto out;
+	}
 
 	violations =
 	    securityfs_create_file("violations", S_IRUSR | S_IRGRP,
 				   ima_dir, NULL, &ima_htable_violations_ops);
-	if (IS_ERR(violations))
+	if (IS_ERR(violations)) {
+		ret = PTR_ERR(violations);
 		goto out;
+	}
 
 	ima_policy = securityfs_create_file("policy", POLICY_FILE_FLAGS,
 					    ima_dir, NULL,
 					    &ima_measure_policy_ops);
-	if (IS_ERR(ima_policy))
+	if (IS_ERR(ima_policy)) {
+		ret = PTR_ERR(ima_policy);
 		goto out;
+	}
 
 	return 0;
 out:
···
 	securityfs_remove(binary_runtime_measurements);
 	securityfs_remove(ima_symlink);
 	securityfs_remove(ima_dir);
-	return -1;
+
+	return ret;
 }

security/integrity/ima/ima_init.c

···
 	struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
 	struct ima_event_data event_data = { .iint = iint,
 					     .filename = boot_aggregate_name };
+	struct ima_max_digest_data hash;
 	int result = -ENOMEM;
 	int violation = 0;
-	struct {
-		struct ima_digest_data hdr;
-		char digest[TPM_MAX_DIGEST_SIZE];
-	} hash;
 
 	memset(iint, 0, sizeof(*iint));
 	memset(&hash, 0, sizeof(hash));

security/integrity/ima/ima_main.c

···
 		/* reset appraisal flags if ima_inode_post_setattr was called */
 		iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
 				 IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
-				 IMA_ACTION_FLAGS);
+				 IMA_NONACTION_FLAGS);
 
 	/*
 	 * Re-evaulate the file if either the xattr has changed or the
···
  *	      call to ima_post_load_data().
  *
  * Callers of this LSM hook can not measure, appraise, or audit the
- * data provided by userspace.  Enforce policy rules requring a file
+ * data provided by userspace.  Enforce policy rules requiring a file
  * signature (eg. kexec'ed kernel image).
  *
  * For permission return 0, otherwise return -EACCES.
···
 					    .buf = buf,
 					    .buf_len = size};
 	struct ima_template_desc *template;
-	struct {
-		struct ima_digest_data hdr;
-		char digest[IMA_MAX_DIGEST_SIZE];
-	} hash = {};
+	struct ima_max_digest_data hash;
 	char digest_hash[IMA_MAX_DIGEST_SIZE];
 	int digest_hash_len = hash_digest_size[ima_hash_algo];
 	int violation = 0;

security/integrity/ima/ima_policy.c

···
 	/*
 	 * ima_lsm_copy_rule() shallow copied all references, except for the
 	 * LSM references, from entry to nentry so we only want to free the LSM
-	 * references and the entry itself. All other memory refrences will now
+	 * references and the entry itself. All other memory references will now
 	 * be owned by nentry.
 	 */
 	ima_lsm_free_rule(entry);
···
 				     func, mask, func_data))
 			continue;
 
-		action |= entry->flags & IMA_ACTION_FLAGS;
+		action |= entry->flags & IMA_NONACTION_FLAGS;
 
 		action |= entry->action & IMA_DO_MASK;
 		if (entry->action & IMA_APPRAISE) {

security/integrity/ima/ima_template_lib.c

···
 	 * digest formats:
 	 *  - DATA_FMT_DIGEST: digest
 	 *  - DATA_FMT_DIGEST_WITH_ALGO: [<hash algo>] + ':' + '\0' + digest,
-	 *    where <hash algo> is provided if the hash algoritm is not
+	 *    where <hash algo> is provided if the hash algorithm is not
 	 *    SHA1 or MD5
 	 */
 	u8 buffer[CRYPTO_MAX_ALG_NAME + 2 + IMA_MAX_DIGEST_SIZE] = { 0 };
···
 int ima_eventdigest_init(struct ima_event_data *event_data,
 			 struct ima_field_data *field_data)
 {
-	struct {
-		struct ima_digest_data hdr;
-		char digest[IMA_MAX_DIGEST_SIZE];
-	} hash;
+	struct ima_max_digest_data hash;
 	u8 *cur_digest = NULL;
 	u32 cur_digestsize = 0;
 	struct inode *inode;

security/integrity/integrity.h

···
 #include <linux/types.h>
 #include <linux/integrity.h>
 #include <crypto/sha1.h>
+#include <crypto/hash.h>
 #include <linux/key.h>
 #include <linux/audit.h>
 
···
 #define IMA_HASH		0x00000100
 #define IMA_HASHED		0x00000200
 
-/* iint cache flags */
-#define IMA_ACTION_FLAGS	0xff000000
+/* iint policy rule cache flags */
+#define IMA_NONACTION_FLAGS	0xff000000
 #define IMA_DIGSIG_REQUIRED	0x01000000
 #define IMA_PERMIT_DIRECTIO	0x02000000
 #define IMA_NEW_FILE		0x04000000
···
 		u8 data[2];
 	} xattr;
 	u8 digest[];
+} __packed;
+
+/*
+ * Instead of wrapping the ima_digest_data struct inside a local structure
+ * with the maximum hash size, define ima_max_digest_data struct.
+ */
+struct ima_max_digest_data {
+	struct ima_digest_data hdr;
+	u8 digest[HASH_MAX_DIGESTSIZE];
 } __packed;
 
 /*

security/keys/Kconfig

···
 	select CRYPTO_RNG
 	help
 	  This option provides support for create/encrypting/decrypting keys
-	  in the kernel.  Encrypted keys are kernel generated random numbers,
-	  which are encrypted/decrypted with a 'master' symmetric key. The
-	  'master' key can be either a trusted-key or user-key type.
-	  Userspace only ever sees/stores encrypted blobs.
+	  in the kernel.  Encrypted keys are instantiated using kernel
+	  generated random numbers or provided decrypted data, and are
+	  encrypted/decrypted with a 'master' symmetric key. The 'master'
+	  key can be either a trusted-key or user-key type. Only encrypted
+	  blobs are ever output to Userspace.
+
+	  If you are unsure as to whether this is required, answer N.
+
+config USER_DECRYPTED_DATA
+	bool "Allow encrypted keys with user decrypted data"
+	depends on ENCRYPTED_KEYS
+	help
+	  This option provides support for instantiating encrypted keys using
+	  user-provided decrypted data.  The decrypted data must be hex-ascii
+	  encoded.
 
 	  If you are unsure as to whether this is required, answer N.
 

security/keys/encrypted-keys/encrypted.c

···
 	{Opt_err, NULL}
 };
 
+static bool user_decrypted_data = IS_ENABLED(CONFIG_USER_DECRYPTED_DATA);
+module_param(user_decrypted_data, bool, 0);
+MODULE_PARM_DESC(user_decrypted_data,
+	"Allow instantiation of encrypted keys using provided decrypted data");
+
 static int aes_get_sizes(void)
 {
 	struct crypto_skcipher *tfm;
···
  * datablob_parse - parse the keyctl data
  *
  * datablob format:
- * new [<format>] <master-key name> <decrypted data length>
+ * new [<format>] <master-key name> <decrypted data length> [<decrypted data>]
  * load [<format>] <master-key name> <decrypted data length>
  *     <encrypted iv + data>
  * update <new-master-key name>
···
  */
 static int datablob_parse(char *datablob, const char **format,
 			  char **master_desc, char **decrypted_datalen,
-			  char **hex_encoded_iv)
+			  char **hex_encoded_iv, char **decrypted_data)
 {
 	substring_t args[MAX_OPT_ARGS];
 	int ret = -EINVAL;
···
 				"when called from .update method\n", keyword);
 			break;
 		}
+		*decrypted_data = strsep(&datablob, " \t");
 		ret = 0;
 		break;
 	case Opt_load:
···
 static struct encrypted_key_payload *encrypted_key_alloc(struct key *key,
 							 const char *format,
 							 const char *master_desc,
-							 const char *datalen)
+							 const char *datalen,
+							 const char *decrypted_data)
 {
 	struct encrypted_key_payload *epayload = NULL;
 	unsigned short datablob_len;
···
 	unsigned int encrypted_datalen;
 	unsigned int format_len;
 	long dlen;
+	int i;
 	int ret;
 
 	ret = kstrtol(datalen, 10, &dlen);
···
 	format_len = (!format) ? strlen(key_format_default) : strlen(format);
 	decrypted_datalen = dlen;
 	payload_datalen = decrypted_datalen;
+
+	if (decrypted_data) {
+		if (!user_decrypted_data) {
+			pr_err("encrypted key: instantiation of keys using provided decrypted data is disabled since CONFIG_USER_DECRYPTED_DATA is set to false\n");
+			return ERR_PTR(-EINVAL);
+		}
+		if (strlen(decrypted_data) != decrypted_datalen) {
+			pr_err("encrypted key: decrypted data provided does not match decrypted data length provided\n");
+			return ERR_PTR(-EINVAL);
+		}
+		for (i = 0; i < strlen(decrypted_data); i++) {
+			if (!isxdigit(decrypted_data[i])) {
+				pr_err("encrypted key: decrypted data provided must contain only hexadecimal characters\n");
+				return ERR_PTR(-EINVAL);
+			}
+		}
+	}
+
 	if (format) {
 		if (!strcmp(format, key_format_ecryptfs)) {
 			if (dlen != ECRYPTFS_MAX_KEY_BYTES) {
···
 /*
  * encrypted_init - initialize an encrypted key
  *
- * For a new key, use a random number for both the iv and data
- * itself.  For an old key, decrypt the hex encoded data.
+ * For a new key, use either a random number or user-provided decrypted data in
+ * case it is provided. A random number is used for the iv in both cases. For
+ * an old key, decrypt the hex encoded data.
  */
 static int encrypted_init(struct encrypted_key_payload *epayload,
 			  const char *key_desc, const char *format,
 			  const char *master_desc, const char *datalen,
-			  const char *hex_encoded_iv)
+			  const char *hex_encoded_iv, const char *decrypted_data)
 {
 	int ret = 0;
 
···
 	}
 
 	__ekey_init(epayload, format, master_desc, datalen);
-	if (!hex_encoded_iv) {
-		get_random_bytes(epayload->iv, ivsize);
-
-		get_random_bytes(epayload->decrypted_data,
-				 epayload->decrypted_datalen);
-	} else
+	if (hex_encoded_iv) {
 		ret = encrypted_key_decrypt(epayload, format, hex_encoded_iv);
+	} else if (decrypted_data) {
+		get_random_bytes(epayload->iv, ivsize);
+		memcpy(epayload->decrypted_data, decrypted_data,
+				   epayload->decrypted_datalen);
+	} else {
+		get_random_bytes(epayload->iv, ivsize);
+		get_random_bytes(epayload->decrypted_data, epayload->decrypted_datalen);
+	}
 	return ret;
 }
 
 /*
  * encrypted_instantiate - instantiate an encrypted key
  *
- * Decrypt an existing encrypted datablob or create a new encrypted key
- * based on a kernel random number.
+ * Instantiates the key:
+ * - by decrypting an existing encrypted datablob, or
+ * - by creating a new encrypted key based on a kernel random number, or
+ * - using provided decrypted data.
  *
  * On success, return 0. Otherwise return errno.
  */
···
 	char *master_desc = NULL;
 	char *decrypted_datalen = NULL;
 	char *hex_encoded_iv = NULL;
+	char *decrypted_data = NULL;
 	size_t datalen = prep->datalen;
 	int ret;
 
···
 	datablob[datalen] = 0;
 	memcpy(datablob, prep->data, datalen);
 	ret = datablob_parse(datablob, &format, &master_desc,
-			     &decrypted_datalen, &hex_encoded_iv);
+			     &decrypted_datalen, &hex_encoded_iv, &decrypted_data);
 	if (ret < 0)
 		goto out;
 
 	epayload = encrypted_key_alloc(key, format, master_desc,
-				       decrypted_datalen);
+				       decrypted_datalen, decrypted_data);
 	if (IS_ERR(epayload)) {
 		ret = PTR_ERR(epayload);
 		goto out;
 	}
 	ret = encrypted_init(epayload, key->description, format, master_desc,
-			     decrypted_datalen, hex_encoded_iv);
+			     decrypted_datalen, hex_encoded_iv, decrypted_data);
 	if (ret < 0) {
 		kfree_sensitive(epayload);
 		goto out;
···
 
 	buf[datalen] = 0;
 	memcpy(buf, prep->data, datalen);
-	ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL);
+	ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL, NULL);
 	if (ret < 0)
 		goto out;
 
···
 		goto out;
 
 	new_epayload = encrypted_key_alloc(key, epayload->format,
-					   new_master_desc, epayload->datalen);
+					   new_master_desc, epayload->datalen, NULL);
 	if (IS_ERR(new_epayload)) {
 		ret = PTR_ERR(new_epayload);
 		goto out;