1 // SPDX-License-Identifier: GPL-2.0
7  * Refer to Documentation/block/inline-encryption.rst for detailed explanation.
10 #define pr_fmt(fmt) "blk-crypto: " fmt
14 #include <linux/blk-crypto-profile.h>
19 #include "blk-crypto-internal.h"
23 		.name = "AES-256-XTS",
30 		.name = "AES-128-CBC-ESSIV",
44 		.name = "SM4-XTS",
62 		"Number of bio crypto contexts to preallocate");
84 	 * Validate the crypto mode properties.  This ideally would be done with  in bio_crypt_ctx_init()
85 	 * static assertions, but boot-time checks are the next best thing.  in bio_crypt_ctx_init()
114 	bc->bc_key = key;  in bio_crypt_set_ctx()
115 	memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun));  in bio_crypt_set_ctx()
117 	bio->bi_crypt_context = bc;  in bio_crypt_set_ctx()
122 	mempool_free(bio->bi_crypt_context, bio_crypt_ctx_pool);  in __bio_crypt_free_ctx()
123 	bio->bi_crypt_context = NULL;  in __bio_crypt_free_ctx()
128 	dst->bi_crypt_context = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);  in __bio_crypt_clone()
129 	if (!dst->bi_crypt_context)  in __bio_crypt_clone()
130 		return -ENOMEM;  in __bio_crypt_clone()
131 	*dst->bi_crypt_context = *src->bi_crypt_context;  in __bio_crypt_clone()
135 /* Increments @dun by @inc, treating @dun as a multi-limb integer. */
156 	struct bio_crypt_ctx *bc = bio->bi_crypt_context;  in __bio_crypt_advance()
158 	bio_crypt_dun_increment(bc->bc_dun,  in __bio_crypt_advance()
159 				bytes >> bc->bc_key->data_unit_size_bits);  in __bio_crypt_advance()
163  * Returns true if @bc->bc_dun plus @bytes converted to data units is equal to
164  * @next_dun, treating the DUNs as multi-limb integers.
171 	unsigned int carry = bytes >> bc->bc_key->data_unit_size_bits;  in bio_crypt_dun_is_contiguous()
174 		if (bc->bc_dun[i] + carry != next_dun[i])  in bio_crypt_dun_is_contiguous()
180 		if ((bc->bc_dun[i] + carry) < carry)  in bio_crypt_dun_is_contiguous()
191  * Checks that two bio crypt contexts are compatible - i.e. that
200 	return bc2 && bc1->bc_key == bc2->bc_key;  in bio_crypt_ctx_compatible()
205 	return bio_crypt_ctx_compatible(rq->crypt_ctx, bio->bi_crypt_context);  in bio_crypt_rq_ctx_compatible()
219 	return !bc1 || bio_crypt_dun_is_contiguous(bc1, bc1_bytes, bc2->bc_dun);  in bio_crypt_ctx_mergeable()
226 		bio->bi_crypt_context->bc_key->crypto_cfg.data_unit_size;  in bio_crypt_check_alignment()
240 	return blk_crypto_get_keyslot(rq->q->crypto_profile,  in __blk_crypto_rq_get_keyslot()
241 				      rq->crypt_ctx->bc_key,  in __blk_crypto_rq_get_keyslot()
242 				      &rq->crypt_keyslot);  in __blk_crypto_rq_get_keyslot()
247 	blk_crypto_put_keyslot(rq->crypt_keyslot);  in __blk_crypto_rq_put_keyslot()
248 	rq->crypt_keyslot = NULL;  in __blk_crypto_rq_put_keyslot()
254 	if (WARN_ON_ONCE(rq->crypt_keyslot))  in __blk_crypto_free_request()
257 	mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool);  in __blk_crypto_free_request()
258 	rq->crypt_ctx = NULL;  in __blk_crypto_free_request()
262  * __blk_crypto_bio_prep - Prepare bio for inline encryption
270  * kernel crypto API. When the crypto API fallback is used for encryption,
271  * blk-crypto may choose to split the bio into 2 - the first one that will
279  * Return: true on success; false on error (and bio->bi_status will be set
286 	const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key;  in __blk_crypto_bio_prep()
290 		bio->bi_status = BLK_STS_IOERR;  in __blk_crypto_bio_prep()
295 		bio->bi_status = BLK_STS_IOERR;  in __blk_crypto_bio_prep()
301 	 * in falling back to the crypto API.  in __blk_crypto_bio_prep()
303 	if (blk_crypto_config_supported_natively(bio->bi_bdev,  in __blk_crypto_bio_prep()
304 						 &bc_key->crypto_cfg))  in __blk_crypto_bio_prep()
316 	if (!rq->crypt_ctx) {  in __blk_crypto_rq_bio_prep()
317 		rq->crypt_ctx = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);  in __blk_crypto_rq_bio_prep()
318 		if (!rq->crypt_ctx)  in __blk_crypto_rq_bio_prep()
319 			return -ENOMEM;  in __blk_crypto_rq_bio_prep()
321 	*rq->crypt_ctx = *bio->bi_crypt_context;  in __blk_crypto_rq_bio_prep()
326  * blk_crypto_init_key() - Prepare a key for use with blk-crypto
330  * @key_type: type of the key -- either raw or hardware-wrapped
336  * Return: 0 on success, -errno on failure.  The caller is responsible for
351 		return -EINVAL;  in blk_crypto_init_key()
356 		if (key_size != mode->keysize)  in blk_crypto_init_key()
357 			return -EINVAL;  in blk_crypto_init_key()
360 		if (key_size < mode->security_strength ||  in blk_crypto_init_key()
362 			return -EINVAL;  in blk_crypto_init_key()
365 		return -EINVAL;  in blk_crypto_init_key()
368 	if (dun_bytes == 0 || dun_bytes > mode->ivsize)  in blk_crypto_init_key()
369 		return -EINVAL;  in blk_crypto_init_key()
372 		return -EINVAL;  in blk_crypto_init_key()
374 	blk_key->crypto_cfg.crypto_mode = crypto_mode;  in blk_crypto_init_key()
375 	blk_key->crypto_cfg.dun_bytes = dun_bytes;  in blk_crypto_init_key()
376 	blk_key->crypto_cfg.data_unit_size = data_unit_size;  in blk_crypto_init_key()
377 	blk_key->crypto_cfg.key_type = key_type;  in blk_crypto_init_key()
378 	blk_key->data_unit_size_bits = ilog2(data_unit_size);  in blk_crypto_init_key()
379 	blk_key->size = key_size;  in blk_crypto_init_key()
380 	memcpy(blk_key->bytes, key_bytes, key_size);  in blk_crypto_init_key()
388 	return __blk_crypto_cfg_supported(bdev_get_queue(bdev)->crypto_profile,  in blk_crypto_config_supported_natively()
393  * Check if bios with @cfg can be en/decrypted by blk-crypto (i.e. either the
394  * block_device it's submitted to supports inline crypto, or the
395  * blk-crypto-fallback is enabled and supports the cfg).
401 	    cfg->key_type == BLK_CRYPTO_KEY_TYPE_RAW)  in blk_crypto_config_supported()
407  * blk_crypto_start_using_key() - Start using a blk_crypto_key on a device
412  * supports the key's crypto settings, or the crypto API fallback has transforms
417  * Return: 0 on success; -EOPNOTSUPP if the key is wrapped but the hardware does
418  *	   not support wrapped keys; -ENOPKG if the key is a raw key but the
419  *	   hardware does not support raw keys and blk-crypto-fallback is either
420  *	   disabled or the needed algorithm is disabled in the crypto API; or
421  *	   another -errno code if something else went wrong.
426 	if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))  in blk_crypto_start_using_key()
428 	if (key->crypto_cfg.key_type != BLK_CRYPTO_KEY_TYPE_RAW) {  in blk_crypto_start_using_key()
430 		return -EOPNOTSUPP;  in blk_crypto_start_using_key()
432 	return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode);  in blk_crypto_start_using_key()
436  * blk_crypto_evict_key() - Evict a blk_crypto_key from a block_device
442  * keyslot(s) or blk-crypto-fallback keyslot it may have been programmed into.
456 	if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))  in blk_crypto_evict_key()
457 		err = __blk_crypto_evict_key(q->crypto_profile, key);  in blk_crypto_evict_key()
482 		return -EFAULT;  in blk_crypto_ioctl_import_key()
485 		return -EINVAL;  in blk_crypto_ioctl_import_key()
488 		return -EINVAL;  in blk_crypto_ioctl_import_key()
492 		ret = -EFAULT;  in blk_crypto_ioctl_import_key()
499 		ret = -EOVERFLOW;  in blk_crypto_ioctl_import_key()
506 		ret = -EFAULT;  in blk_crypto_ioctl_import_key()
525 		return -EFAULT;  in blk_crypto_ioctl_generate_key()
528 		return -EINVAL;  in blk_crypto_ioctl_generate_key()
534 		ret = -EOVERFLOW;  in blk_crypto_ioctl_generate_key()
541 		ret = -EFAULT;  in blk_crypto_ioctl_generate_key()
560 		return -EFAULT;  in blk_crypto_ioctl_prepare_key()
563 		return -EINVAL;  in blk_crypto_ioctl_prepare_key()
566 		return -EINVAL;  in blk_crypto_ioctl_prepare_key()
570 		ret = -EFAULT;  in blk_crypto_ioctl_prepare_key()
577 		ret = -EOVERFLOW;  in blk_crypto_ioctl_prepare_key()
584 		ret = -EFAULT;  in blk_crypto_ioctl_prepare_key()
599 		bdev_get_queue(bdev)->crypto_profile;  in blk_crypto_ioctl()
602 		return -EOPNOTSUPP;  in blk_crypto_ioctl()
612 		return -ENOTTY;  in blk_crypto_ioctl()