crypto: skcipher - remove the "blkcipher" algorithm type

Now that all "blkcipher" algorithms have been converted to "skcipher",
remove the blkcipher algorithm type.

The skcipher (symmetric key cipher) algorithm type was introduced a few
years ago to replace both blkcipher and ablkcipher (synchronous and
asynchronous block cipher).  The advantages of skcipher include:

  - A much less confusing name, since none of these algorithm types have
    ever actually been for raw block ciphers, but rather for all
    length-preserving encryption modes including block cipher modes of
    operation, stream ciphers, and other length-preserving modes.

  - It unified blkcipher and ablkcipher into a single algorithm type
    which supports both synchronous and asynchronous implementations.
    Note, blkcipher already operated only on scatterlists, so the fact
    that skcipher does too isn't a regression in functionality.

  - Better type safety by using struct skcipher_alg, struct
    crypto_skcipher, etc. instead of crypto_alg, crypto_tfm, etc.

  - It sometimes simplifies the implementations of algorithms.

Also, the blkcipher API was no longer being tested.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Documentation/crypto/api-skcipher.rst

@@ -5,7 +5,7 @@ Block Cipher Algorithm Definitions
    :doc: Block Cipher Algorithm Definitions
 
 .. kernel-doc:: include/linux/crypto.h
-   :functions: crypto_alg ablkcipher_alg blkcipher_alg cipher_alg compress_alg
+   :functions: crypto_alg ablkcipher_alg cipher_alg compress_alg
 
 Symmetric Key Cipher API
 ------------------------
@@ -51,12 +51,3 @@ Asynchronous Cipher Request Handle - Deprecated
 
 .. kernel-doc:: include/linux/crypto.h
    :functions: crypto_ablkcipher_reqsize ablkcipher_request_set_tfm ablkcipher_request_alloc ablkcipher_request_free ablkcipher_request_set_callback ablkcipher_request_set_crypt
-
-Synchronous Block Cipher API - Deprecated
------------------------------------------
-
-.. kernel-doc:: include/linux/crypto.h
-   :doc: Synchronous Block Cipher API
-
-.. kernel-doc:: include/linux/crypto.h
-   :functions: crypto_alloc_blkcipher crypto_free_blkcipher crypto_has_blkcipher crypto_blkcipher_name crypto_blkcipher_ivsize crypto_blkcipher_blocksize crypto_blkcipher_setkey crypto_blkcipher_encrypt crypto_blkcipher_encrypt_iv crypto_blkcipher_decrypt crypto_blkcipher_decrypt_iv crypto_blkcipher_set_iv crypto_blkcipher_get_iv

Documentation/crypto/architecture.rst

@@ -201,8 +201,6 @@ the aforementioned cipher types:
 -  CRYPTO_ALG_TYPE_AEAD Authenticated Encryption with Associated Data
    (MAC)
 
--  CRYPTO_ALG_TYPE_BLKCIPHER Synchronous multi-block cipher
-
 -  CRYPTO_ALG_TYPE_ABLKCIPHER Asynchronous multi-block cipher
 
 -  CRYPTO_ALG_TYPE_KPP Key-agreement Protocol Primitive (KPP) such as

Documentation/crypto/devel-algos.rst

@@ -128,25 +128,20 @@ process requests that are unaligned. This implies, however, additional
 overhead as the kernel crypto API needs to perform the realignment of
 the data which may imply moving of data.
 
-Cipher Definition With struct blkcipher_alg and ablkcipher_alg
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Cipher Definition With struct skcipher_alg
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Struct blkcipher_alg defines a synchronous block cipher whereas struct
-ablkcipher_alg defines an asynchronous block cipher.
+Struct skcipher_alg defines a multi-block cipher, or more generally, a
+length-preserving symmetric cipher algorithm.
 
-Please refer to the single block cipher description for schematics of
-the block cipher usage.
+Scatterlist handling
+~~~~~~~~~~~~~~~~~~~~
 
-Specifics Of Asynchronous Multi-Block Cipher
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-There are a couple of specifics to the asynchronous interface.
-
-First of all, some of the drivers will want to use the Generic
-ScatterWalk in case the hardware needs to be fed separate chunks of the
-scatterlist which contains the plaintext and will contain the
-ciphertext. Please refer to the ScatterWalk interface offered by the
-Linux kernel scatter / gather list implementation.
+Some drivers will want to use the Generic ScatterWalk in case the
+hardware needs to be fed separate chunks of the scatterlist which
+contains the plaintext and will contain the ciphertext. Please refer
+to the ScatterWalk interface offered by the Linux kernel scatter /
+gather list implementation.
 
 Hashing [HASH]
 --------------

crypto/Makefile

@@ -16,7 +16,6 @@ obj-$(CONFIG_CRYPTO_ALGAPI2) += crypto_algapi.o
 obj-$(CONFIG_CRYPTO_AEAD2) += aead.o
 
 crypto_blkcipher-y := ablkcipher.o
-crypto_blkcipher-y += blkcipher.o
 crypto_blkcipher-y += skcipher.o
 obj-$(CONFIG_CRYPTO_BLKCIPHER2) += crypto_blkcipher.o
 obj-$(CONFIG_CRYPTO_SEQIV) += seqiv.o

crypto/api.c

@@ -406,7 +406,7 @@ EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
  *
  *	The returned transform is of a non-determinate type.  Most people
  *	should use one of the more specific allocation functions such as
- *	crypto_alloc_blkcipher.
+ *	crypto_alloc_skcipher().
  *
  *	In case of error the return value is an error pointer.
  */

crypto/cryptd.c

@@ -919,7 +919,7 @@ static int cryptd_create(struct crypto_template *tmpl, struct rtattr **tb)
 		return PTR_ERR(algt);
 
 	switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
-	case CRYPTO_ALG_TYPE_BLKCIPHER:
+	case CRYPTO_ALG_TYPE_SKCIPHER:
 		return cryptd_create_skcipher(tmpl, tb, &queue);
 	case CRYPTO_ALG_TYPE_HASH:
 		return cryptd_create_hash(tmpl, tb, &queue);

crypto/crypto_user_stat.c

@@ -213,10 +213,6 @@ static int crypto_reportstat_one(struct crypto_alg *alg,
 		if (crypto_report_cipher(skb, alg))
 			goto nla_put_failure;
 		break;
-	case CRYPTO_ALG_TYPE_BLKCIPHER:
-		if (crypto_report_cipher(skb, alg))
-			goto nla_put_failure;
-		break;
 	case CRYPTO_ALG_TYPE_CIPHER:
 		if (crypto_report_cipher(skb, alg))
 			goto nla_put_failure;

crypto/essiv.c

@@ -486,7 +486,7 @@ static int essiv_create(struct crypto_template *tmpl, struct rtattr **tb)
 	type = algt->type & algt->mask;
 
 	switch (type) {
-	case CRYPTO_ALG_TYPE_BLKCIPHER:
+	case CRYPTO_ALG_TYPE_SKCIPHER:
 		skcipher_inst = kzalloc(sizeof(*skcipher_inst) +
 					sizeof(*ictx), GFP_KERNEL);
 		if (!skcipher_inst)
@@ -586,7 +586,7 @@ static int essiv_create(struct crypto_template *tmpl, struct rtattr **tb)
 	base->cra_alignmask	= block_base->cra_alignmask;
 	base->cra_priority	= block_base->cra_priority;
 
-	if (type == CRYPTO_ALG_TYPE_BLKCIPHER) {
+	if (type == CRYPTO_ALG_TYPE_SKCIPHER) {
 		skcipher_inst->alg.setkey	= essiv_skcipher_setkey;
 		skcipher_inst->alg.encrypt	= essiv_skcipher_encrypt;
 		skcipher_inst->alg.decrypt	= essiv_skcipher_decrypt;
@@ -628,7 +628,7 @@ static int essiv_create(struct crypto_template *tmpl, struct rtattr **tb)
 out_free_hash:
 	crypto_mod_put(_hash_alg);
 out_drop_skcipher:
-	if (type == CRYPTO_ALG_TYPE_BLKCIPHER)
+	if (type == CRYPTO_ALG_TYPE_SKCIPHER)
 		crypto_drop_skcipher(&ictx->u.skcipher_spawn);
 	else
 		crypto_drop_aead(&ictx->u.aead_spawn);

crypto/skcipher.c

@@ -580,9 +580,6 @@ EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
 
 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
 {
-	if (alg->cra_type == &crypto_blkcipher_type)
-		return sizeof(struct crypto_blkcipher *);
-
 	if (alg->cra_type == &crypto_ablkcipher_type)
 		return sizeof(struct crypto_ablkcipher *);
 
@@ -595,105 +592,6 @@ static void skcipher_set_needkey(struct crypto_skcipher *tfm)
 		crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 }
 
-static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
-				     const u8 *key, unsigned int keylen)
-{
-	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
-	struct crypto_blkcipher *blkcipher = *ctx;
-	int err;
-
-	crypto_blkcipher_clear_flags(blkcipher, ~0);
-	crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
-					      CRYPTO_TFM_REQ_MASK);
-	err = crypto_blkcipher_setkey(blkcipher, key, keylen);
-	crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
-				       CRYPTO_TFM_RES_MASK);
-	if (unlikely(err)) {
-		skcipher_set_needkey(tfm);
-		return err;
-	}
-
-	crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
-	return 0;
-}
-
-static int skcipher_crypt_blkcipher(struct skcipher_request *req,
-				    int (*crypt)(struct blkcipher_desc *,
-						 struct scatterlist *,
-						 struct scatterlist *,
-						 unsigned int))
-{
-	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
-	struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
-	struct blkcipher_desc desc = {
-		.tfm = *ctx,
-		.info = req->iv,
-		.flags = req->base.flags,
-	};
-
-
-	return crypt(&desc, req->dst, req->src, req->cryptlen);
-}
-
-static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
-{
-	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
-	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
-	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
-
-	return skcipher_crypt_blkcipher(req, alg->encrypt);
-}
-
-static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
-{
-	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
-	struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
-	struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
-
-	return skcipher_crypt_blkcipher(req, alg->decrypt);
-}
-
-static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
-{
-	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
-
-	crypto_free_blkcipher(*ctx);
-}
-
-static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
-{
-	struct crypto_alg *calg = tfm->__crt_alg;
-	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
-	struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
-	struct crypto_blkcipher *blkcipher;
-	struct crypto_tfm *btfm;
-
-	if (!crypto_mod_get(calg))
-		return -EAGAIN;
-
-	btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
-					CRYPTO_ALG_TYPE_MASK);
-	if (IS_ERR(btfm)) {
-		crypto_mod_put(calg);
-		return PTR_ERR(btfm);
-	}
-
-	blkcipher = __crypto_blkcipher_cast(btfm);
-	*ctx = blkcipher;
-	tfm->exit = crypto_exit_skcipher_ops_blkcipher;
-
-	skcipher->setkey = skcipher_setkey_blkcipher;
-	skcipher->encrypt = skcipher_encrypt_blkcipher;
-	skcipher->decrypt = skcipher_decrypt_blkcipher;
-
-	skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
-	skcipher->keysize = calg->cra_blkcipher.max_keysize;
-
-	skcipher_set_needkey(skcipher);
-
-	return 0;
-}
-
 static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
 				      const u8 *key, unsigned int keylen)
 {
@@ -888,9 +786,6 @@ static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 	struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 	struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 
-	if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
-		return crypto_init_skcipher_ops_blkcipher(tfm);
-
 	if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type)
 		return crypto_init_skcipher_ops_ablkcipher(tfm);
 
@@ -973,7 +868,7 @@ static const struct crypto_type crypto_skcipher_type = {
 #endif
 	.report = crypto_skcipher_report,
 	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
-	.maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
+	.maskset = CRYPTO_ALG_TYPE_MASK,
 	.type = CRYPTO_ALG_TYPE_SKCIPHER,
 	.tfmsize = offsetof(struct crypto_skcipher, base),
 };

include/crypto/algapi.h

@@ -85,36 +85,6 @@ struct scatter_walk {
 	unsigned int offset;
 };
 
-struct blkcipher_walk {
-	union {
-		struct {
-			struct page *page;
-			unsigned long offset;
-		} phys;
-
-		struct {
-			u8 *page;
-			u8 *addr;
-		} virt;
-	} src, dst;
-
-	struct scatter_walk in;
-	unsigned int nbytes;
-
-	struct scatter_walk out;
-	unsigned int total;
-
-	void *page;
-	u8 *buffer;
-	u8 *iv;
-	unsigned int ivsize;
-
-	int flags;
-	unsigned int walk_blocksize;
-	unsigned int cipher_blocksize;
-	unsigned int alignmask;
-};
-
 struct ablkcipher_walk {
 	struct {
 		struct page *page;
@@ -133,7 +103,6 @@ struct ablkcipher_walk {
 };
 
 extern const struct crypto_type crypto_ablkcipher_type;
-extern const struct crypto_type crypto_blkcipher_type;
 
 void crypto_mod_put(struct crypto_alg *alg);
 
@@ -233,20 +202,6 @@ static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
 	}
 }
 
-int blkcipher_walk_done(struct blkcipher_desc *desc,
-			struct blkcipher_walk *walk, int err);
-int blkcipher_walk_virt(struct blkcipher_desc *desc,
-			struct blkcipher_walk *walk);
-int blkcipher_walk_phys(struct blkcipher_desc *desc,
-			struct blkcipher_walk *walk);
-int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
-			      struct blkcipher_walk *walk,
-			      unsigned int blocksize);
-int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
-				   struct blkcipher_walk *walk,
-				   struct crypto_aead *tfm,
-				   unsigned int blocksize);
-
 int ablkcipher_walk_done(struct ablkcipher_request *req,
 			 struct ablkcipher_walk *walk, int err);
 int ablkcipher_walk_phys(struct ablkcipher_request *req,
@@ -286,25 +241,6 @@ static inline void *crypto_ablkcipher_ctx_aligned(struct crypto_ablkcipher *tfm)
 	return crypto_tfm_ctx_aligned(&tfm->base);
 }
 
-static inline struct crypto_blkcipher *crypto_spawn_blkcipher(
-	struct crypto_spawn *spawn)
-{
-	u32 type = CRYPTO_ALG_TYPE_BLKCIPHER;
-	u32 mask = CRYPTO_ALG_TYPE_MASK;
-
-	return __crypto_blkcipher_cast(crypto_spawn_tfm(spawn, type, mask));
-}
-
-static inline void *crypto_blkcipher_ctx(struct crypto_blkcipher *tfm)
-{
-	return crypto_tfm_ctx(&tfm->base);
-}
-
-static inline void *crypto_blkcipher_ctx_aligned(struct crypto_blkcipher *tfm)
-{
-	return crypto_tfm_ctx_aligned(&tfm->base);
-}
-
 static inline struct crypto_cipher *crypto_spawn_cipher(
 	struct crypto_spawn *spawn)
 {
@@ -319,16 +255,6 @@ static inline struct cipher_alg *crypto_cipher_alg(struct crypto_cipher *tfm)
 	return &crypto_cipher_tfm(tfm)->__crt_alg->cra_cipher;
 }
 
-static inline void blkcipher_walk_init(struct blkcipher_walk *walk,
-				       struct scatterlist *dst,
-				       struct scatterlist *src,
-				       unsigned int nbytes)
-{
-	walk->in.sg = src;
-	walk->out.sg = dst;
-	walk->total = nbytes;
-}
-
 static inline void ablkcipher_walk_init(struct ablkcipher_walk *walk,
 					struct scatterlist *dst,
 					struct scatterlist *src,

include/crypto/internal/skcipher.h

@@ -182,10 +182,6 @@ static inline u32 skcipher_request_flags(struct skcipher_request *req)
 static inline unsigned int crypto_skcipher_alg_min_keysize(
 	struct skcipher_alg *alg)
 {
-	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
-	    CRYPTO_ALG_TYPE_BLKCIPHER)
-		return alg->base.cra_blkcipher.min_keysize;
-
 	if (alg->base.cra_ablkcipher.encrypt)
 		return alg->base.cra_ablkcipher.min_keysize;
 
@@ -195,10 +191,6 @@ static inline unsigned int crypto_skcipher_alg_min_keysize(
 static inline unsigned int crypto_skcipher_alg_max_keysize(
 	struct skcipher_alg *alg)
 {
-	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
-	    CRYPTO_ALG_TYPE_BLKCIPHER)
-		return alg->base.cra_blkcipher.max_keysize;
-
 	if (alg->base.cra_ablkcipher.encrypt)
 		return alg->base.cra_ablkcipher.max_keysize;
 
@@ -208,10 +200,6 @@ static inline unsigned int crypto_skcipher_alg_max_keysize(
 static inline unsigned int crypto_skcipher_alg_walksize(
 	struct skcipher_alg *alg)
 {
-	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
-	    CRYPTO_ALG_TYPE_BLKCIPHER)
-		return alg->base.cra_blocksize;
-
 	if (alg->base.cra_ablkcipher.encrypt)
 		return alg->base.cra_blocksize;
 

include/crypto/skcipher.h

@@ -241,10 +241,6 @@ static inline struct skcipher_alg *crypto_skcipher_alg(
 
 static inline unsigned int crypto_skcipher_alg_ivsize(struct skcipher_alg *alg)
 {
-	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
-	    CRYPTO_ALG_TYPE_BLKCIPHER)
-		return alg->base.cra_blkcipher.ivsize;
-
 	if (alg->base.cra_ablkcipher.encrypt)
 		return alg->base.cra_ablkcipher.ivsize;
 
@@ -290,10 +286,6 @@ static inline unsigned int crypto_skcipher_blocksize(
 static inline unsigned int crypto_skcipher_alg_chunksize(
 	struct skcipher_alg *alg)
 {
-	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
-	    CRYPTO_ALG_TYPE_BLKCIPHER)
-		return alg->base.cra_blocksize;
-
 	if (alg->base.cra_ablkcipher.encrypt)
 		return alg->base.cra_blocksize;
 

net/xfrm/xfrm_algo.c

@@ -626,8 +626,8 @@ static const struct xfrm_algo_list xfrm_aalg_list = {
 static const struct xfrm_algo_list xfrm_ealg_list = {
 	.algs = ealg_list,
 	.entries = ARRAY_SIZE(ealg_list),
-	.type = CRYPTO_ALG_TYPE_BLKCIPHER,
-	.mask = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
+	.type = CRYPTO_ALG_TYPE_SKCIPHER,
+	.mask = CRYPTO_ALG_TYPE_MASK,
 };
 
 static const struct xfrm_algo_list xfrm_calg_list = {