3  * Encryption policy functions for per-file encryption support.
10  * Modified by Eric Biggers, 2019 for v2 policy support.
22  * @policy1: the first policy
23  * @policy2: the second policy
36 int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,  in fscrypt_policy_to_key_spec()  argument
39 	switch (policy->version) {  in fscrypt_policy_to_key_spec()
42 		memcpy(key_spec->u.descriptor, policy->v1.master_key_descriptor,  in fscrypt_policy_to_key_spec()
47 		memcpy(key_spec->u.identifier, policy->v2.master_key_identifier,  in fscrypt_policy_to_key_spec()
120 static bool supported_iv_ino_lblk_policy(const struct fscrypt_policy_v2 *policy,  in supported_iv_ino_lblk_policy()  argument
135 	if (policy->contents_encryption_mode != FSCRYPT_MODE_AES_256_XTS) {  in supported_iv_ino_lblk_policy()
137 			     "Can't use %s policy with contents mode other than AES-256-XTS",  in supported_iv_ino_lblk_policy()
149 			     "Can't use %s policy on filesystem '%s' because it doesn't have stable inode numbers",  in supported_iv_ino_lblk_policy()
157 			     "Can't use %s policy on filesystem '%s' because its inode numbers are too long",  in supported_iv_ino_lblk_policy()
163 			     "Can't use %s policy on filesystem '%s' because its block numbers are too long",  in supported_iv_ino_lblk_policy()
170 static bool fscrypt_supported_v1_policy(const struct fscrypt_policy_v1 *policy,  in fscrypt_supported_v1_policy()  argument
173 	if (!fscrypt_valid_enc_modes_v1(policy->contents_encryption_mode,  in fscrypt_supported_v1_policy()
174 				     policy->filenames_encryption_mode)) {  in fscrypt_supported_v1_policy()
177 			     policy->contents_encryption_mode,  in fscrypt_supported_v1_policy()
178 			     policy->filenames_encryption_mode);  in fscrypt_supported_v1_policy()
182 	if (policy->flags & ~(FSCRYPT_POLICY_FLAGS_PAD_MASK |  in fscrypt_supported_v1_policy()
185 			     policy->flags);  in fscrypt_supported_v1_policy()
189 	if ((policy->flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) &&  in fscrypt_supported_v1_policy()
190 	    !supported_direct_key_modes(inode, policy->contents_encryption_mode,  in fscrypt_supported_v1_policy()
191 					policy->filenames_encryption_mode))  in fscrypt_supported_v1_policy()
204 static bool fscrypt_supported_v2_policy(const struct fscrypt_policy_v2 *policy,  in fscrypt_supported_v2_policy()  argument
209 	if (!fscrypt_valid_enc_modes_v2(policy->contents_encryption_mode,  in fscrypt_supported_v2_policy()
210 				     policy->filenames_encryption_mode)) {  in fscrypt_supported_v2_policy()
213 			     policy->contents_encryption_mode,  in fscrypt_supported_v2_policy()
214 			     policy->filenames_encryption_mode);  in fscrypt_supported_v2_policy()
218 	if (policy->flags & ~(FSCRYPT_POLICY_FLAGS_PAD_MASK |  in fscrypt_supported_v2_policy()
223 			     policy->flags);  in fscrypt_supported_v2_policy()
227 	count += !!(policy->flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY);  in fscrypt_supported_v2_policy()
228 	count += !!(policy->flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64);  in fscrypt_supported_v2_policy()
229 	count += !!(policy->flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32);  in fscrypt_supported_v2_policy()
232 			     policy->flags);  in fscrypt_supported_v2_policy()
236 	if ((policy->flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) &&  in fscrypt_supported_v2_policy()
237 	    !supported_direct_key_modes(inode, policy->contents_encryption_mode,  in fscrypt_supported_v2_policy()
238 					policy->filenames_encryption_mode))  in fscrypt_supported_v2_policy()
241 	if ((policy->flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64) &&  in fscrypt_supported_v2_policy()
242 	    !supported_iv_ino_lblk_policy(policy, inode, "IV_INO_LBLK_64",  in fscrypt_supported_v2_policy()
252 	if ((policy->flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32) &&  in fscrypt_supported_v2_policy()
253 	    !supported_iv_ino_lblk_policy(policy, inode, "IV_INO_LBLK_32",  in fscrypt_supported_v2_policy()
257 	if (memchr_inv(policy->__reserved, 0, sizeof(policy->__reserved))) {  in fscrypt_supported_v2_policy()
258 		fscrypt_warn(inode, "Reserved bits set in encryption policy");  in fscrypt_supported_v2_policy()
266  * fscrypt_supported_policy() - check whether an encryption policy is supported
267  * @policy_u: the encryption policy
268  * @inode: the inode on which the policy will be used
270  * Given an encryption policy, check whether all its encryption modes and other
292  * @policy_u: input policy
296  * encryption policy.  @nonce must be a new random nonce.
308 		const struct fscrypt_policy_v1 *policy = &policy_u->v1;  in fscrypt_new_context()  local
313 			policy->contents_encryption_mode;  in fscrypt_new_context()
315 			policy->filenames_encryption_mode;  in fscrypt_new_context()
316 		ctx->flags = policy->flags;  in fscrypt_new_context()
318 		       policy->master_key_descriptor,  in fscrypt_new_context()
324 		const struct fscrypt_policy_v2 *policy = &policy_u->v2;  in fscrypt_new_context()  local
329 			policy->contents_encryption_mode;  in fscrypt_new_context()
331 			policy->filenames_encryption_mode;  in fscrypt_new_context()
332 		ctx->flags = policy->flags;  in fscrypt_new_context()
334 		       policy->master_key_identifier,  in fscrypt_new_context()
346  * @policy_u: output policy
355  * This does *not* validate the settings within the policy itself, e.g. the
370 		struct fscrypt_policy_v1 *policy = &policy_u->v1;  in fscrypt_policy_from_context()  local
372 		policy->version = FSCRYPT_POLICY_V1;  in fscrypt_policy_from_context()
373 		policy->contents_encryption_mode =  in fscrypt_policy_from_context()
375 		policy->filenames_encryption_mode =  in fscrypt_policy_from_context()
377 		policy->flags = ctx->flags;  in fscrypt_policy_from_context()
378 		memcpy(policy->master_key_descriptor,  in fscrypt_policy_from_context()
380 		       sizeof(policy->master_key_descriptor));  in fscrypt_policy_from_context()
385 		struct fscrypt_policy_v2 *policy = &policy_u->v2;  in fscrypt_policy_from_context()  local
387 		policy->version = FSCRYPT_POLICY_V2;  in fscrypt_policy_from_context()
388 		policy->contents_encryption_mode =  in fscrypt_policy_from_context()
390 		policy->filenames_encryption_mode =  in fscrypt_policy_from_context()
392 		policy->flags = ctx->flags;  in fscrypt_policy_from_context()
393 		memcpy(policy->__reserved, ctx->__reserved,  in fscrypt_policy_from_context()
394 		       sizeof(policy->__reserved));  in fscrypt_policy_from_context()
395 		memcpy(policy->master_key_identifier,  in fscrypt_policy_from_context()
397 		       sizeof(policy->master_key_identifier));  in fscrypt_policy_from_context()
405 /* Retrieve an inode's encryption policy */
406 static int fscrypt_get_policy(struct inode *inode, union fscrypt_policy *policy)  in fscrypt_get_policy()  argument
414 		/* key available, use the cached policy */  in fscrypt_get_policy()
415 		*policy = ci->ci_policy;  in fscrypt_get_policy()
426 	return fscrypt_policy_from_context(policy, &ctx, ret);  in fscrypt_get_policy()
430 				 const union fscrypt_policy *policy)  in set_encryption_policy()  argument
437 	if (!fscrypt_supported_policy(policy, inode))  in set_encryption_policy()
440 	switch (policy->version) {  in set_encryption_policy()
443 		 * The original encryption policy version provided no way of  in set_encryption_policy()
447 		 * encryption policy version fixes this and also implies use of  in set_encryption_policy()
451 		 * policy version for all new encrypted directories.  in set_encryption_policy()
453 …pr_warn_once("%s (pid %d) is setting deprecated v1 encryption policy; recommend upgrading to v2.\n…  in set_encryption_policy()
458 					       policy->v2.master_key_identifier);  in set_encryption_policy()
461 		if (policy->v2.flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32)  in set_encryption_policy()
462 …pr_warn_once("%s (pid %d) is setting an IV_INO_LBLK_32 encryption policy.  This should only be use…  in set_encryption_policy()
471 	ctxsize = fscrypt_new_context(&ctx, policy, nonce);  in set_encryption_policy()
478 	union fscrypt_policy policy;  in fscrypt_ioctl_set_policy()  local
485 	if (get_user(policy.version, (const u8 __user *)arg))  in fscrypt_ioctl_set_policy()
488 	size = fscrypt_policy_size(&policy);  in fscrypt_ioctl_set_policy()
503 	version = policy.version;  in fscrypt_ioctl_set_policy()
504 	if (copy_from_user(&policy, arg, size))  in fscrypt_ioctl_set_policy()
506 	policy.version = version;  in fscrypt_ioctl_set_policy()
526 			ret = set_encryption_policy(inode, &policy);  in fscrypt_ioctl_set_policy()
528 		   (ret == 0 && !fscrypt_policies_equal(&policy,  in fscrypt_ioctl_set_policy()
530 		/* The file already uses a different encryption policy. */  in fscrypt_ioctl_set_policy()
541 /* Original ioctl version; can only get the original policy version */
544 	union fscrypt_policy policy;  in fscrypt_ioctl_get_policy()  local
547 	err = fscrypt_get_policy(file_inode(filp), &policy);  in fscrypt_ioctl_get_policy()
551 	if (policy.version != FSCRYPT_POLICY_V1)  in fscrypt_ioctl_get_policy()
554 	if (copy_to_user(arg, &policy, sizeof(policy.v1)))  in fscrypt_ioctl_get_policy()
564 	union fscrypt_policy *policy = (union fscrypt_policy *)&arg.policy;  in fscrypt_ioctl_get_policy_ex()  local
568 	/* arg is policy_size, then policy */  in fscrypt_ioctl_get_policy_ex()
571 		     offsetof(typeof(arg), policy));  in fscrypt_ioctl_get_policy_ex()
572 	BUILD_BUG_ON(sizeof(arg.policy) != sizeof(*policy));  in fscrypt_ioctl_get_policy_ex()
574 	err = fscrypt_get_policy(file_inode(filp), policy);  in fscrypt_ioctl_get_policy_ex()
577 	policy_size = fscrypt_policy_size(policy);  in fscrypt_ioctl_get_policy_ex()
612  * fscrypt_has_permitted_context() - is a file's encryption policy permitted
624  * same encryption policy.  The pre-access check is needed to detect potentially
650 	 * encryption policy.  Compare the fscrypt_info structs if the keys are  in fscrypt_has_permitted_context()
675 	 * encryption policy, so that files with an unrecognized encryption  in fscrypt_has_permitted_context()
676 	 * policy can be deleted.  in fscrypt_has_permitted_context()
689  * Return the encryption policy that new files in the directory will inherit, or
710  * @inode: inode from which to fetch policy and nonce
768  * @dummy_policy: (input/output) the place to write the dummy policy that will
769  *	result from parsing the option.  Zero-initialize this.  If a policy is
780 	union fscrypt_policy *policy;  in fscrypt_parse_test_dummy_encryption()  local
786 	policy = kzalloc(sizeof(*policy), GFP_KERNEL);  in fscrypt_parse_test_dummy_encryption()
787 	if (!policy)  in fscrypt_parse_test_dummy_encryption()
791 		policy->version = FSCRYPT_POLICY_V1;  in fscrypt_parse_test_dummy_encryption()
792 		policy->v1.contents_encryption_mode = FSCRYPT_MODE_AES_256_XTS;  in fscrypt_parse_test_dummy_encryption()
793 		policy->v1.filenames_encryption_mode = FSCRYPT_MODE_AES_256_CTS;  in fscrypt_parse_test_dummy_encryption()
794 		memset(policy->v1.master_key_descriptor, 0x42,  in fscrypt_parse_test_dummy_encryption()
797 		policy->version = FSCRYPT_POLICY_V2;  in fscrypt_parse_test_dummy_encryption()
798 		policy->v2.contents_encryption_mode = FSCRYPT_MODE_AES_256_XTS;  in fscrypt_parse_test_dummy_encryption()
799 		policy->v2.filenames_encryption_mode = FSCRYPT_MODE_AES_256_CTS;  in fscrypt_parse_test_dummy_encryption()
801 				policy->v2.master_key_identifier);  in fscrypt_parse_test_dummy_encryption()
809 	if (dummy_policy->policy) {  in fscrypt_parse_test_dummy_encryption()
810 		if (fscrypt_policies_equal(policy, dummy_policy->policy))  in fscrypt_parse_test_dummy_encryption()
816 	dummy_policy->policy = policy;  in fscrypt_parse_test_dummy_encryption()
817 	policy = NULL;  in fscrypt_parse_test_dummy_encryption()
820 	kfree(policy);  in fscrypt_parse_test_dummy_encryption()
827  * @p1: the first test dummy policy (may be unset)
828  * @p2: the second test dummy policy (may be unset)
835 	if (!p1->policy && !p2->policy)  in fscrypt_dummy_policies_equal()
837 	if (!p1->policy || !p2->policy)  in fscrypt_dummy_policies_equal()
839 	return fscrypt_policies_equal(p1->policy, p2->policy);  in fscrypt_dummy_policies_equal()
855 	const union fscrypt_policy *policy = fscrypt_get_dummy_policy(sb);  in fscrypt_show_test_dummy_encryption()  local
858 	if (!policy)  in fscrypt_show_test_dummy_encryption()
861 	vers = policy->version;  in fscrypt_show_test_dummy_encryption()