crypto: skcipher - Add lskcipher

Add a new API type lskcipher designed for taking straight kernel
pointers instead of SG lists.  Its relationship to skcipher will
be analogous to that between shash and ahash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/Makefile

@@ -16,7 +16,11 @@ obj-$(CONFIG_CRYPTO_ALGAPI2) += crypto_algapi.o
 obj-$(CONFIG_CRYPTO_AEAD2) += aead.o
 obj-$(CONFIG_CRYPTO_GENIV) += geniv.o
 
-obj-$(CONFIG_CRYPTO_SKCIPHER2) += skcipher.o
+crypto_skcipher-y += lskcipher.o
+crypto_skcipher-y += skcipher.o
+
+obj-$(CONFIG_CRYPTO_SKCIPHER2) += crypto_skcipher.o
+
 obj-$(CONFIG_CRYPTO_SEQIV) += seqiv.o
 obj-$(CONFIG_CRYPTO_ECHAINIV) += echainiv.o
 

crypto/cryptd.c

@@ -929,7 +929,7 @@ 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_SKCIPHER:
+	case CRYPTO_ALG_TYPE_LSKCIPHER:
 		return cryptd_create_skcipher(tmpl, tb, algt, &queue);
 	case CRYPTO_ALG_TYPE_HASH:
 		return cryptd_create_hash(tmpl, tb, algt, &queue);

crypto/skcipher.c

@@ -24,8 +24,9 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <net/netlink.h>
+#include "skcipher.h"
 
-#include "internal.h"
+#define CRYPTO_ALG_TYPE_SKCIPHER_MASK	0x0000000e
 
 enum {
 	SKCIPHER_WALK_PHYS = 1 << 0,
@@ -43,6 +44,8 @@ struct skcipher_walk_buffer {
 	u8 buffer[];
 };
 
+static const struct crypto_type crypto_skcipher_type;
+
 static int skcipher_walk_next(struct skcipher_walk *walk);
 
 static inline void skcipher_map_src(struct skcipher_walk *walk)
@@ -89,11 +92,7 @@ static inline struct skcipher_alg *__crypto_skcipher_alg(
 static inline struct crypto_istat_cipher *skcipher_get_stat(
 	struct skcipher_alg *alg)
 {
-#ifdef CONFIG_CRYPTO_STATS
-	return &alg->stat;
-#else
-	return NULL;
-#endif
+	return skcipher_get_stat_common(&alg->co);
 }
 
 static inline int crypto_skcipher_errstat(struct skcipher_alg *alg, int err)
@@ -468,6 +467,7 @@ static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 				  struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 
 	walk->total = req->cryptlen;
 	walk->nbytes = 0;
@@ -485,10 +485,14 @@ static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 		       SKCIPHER_WALK_SLEEP : 0;
 
 	walk->blocksize = crypto_skcipher_blocksize(tfm);
-	walk->stride = crypto_skcipher_walksize(tfm);
 	walk->ivsize = crypto_skcipher_ivsize(tfm);
 	walk->alignmask = crypto_skcipher_alignmask(tfm);
 
+	if (alg->co.base.cra_type != &crypto_skcipher_type)
+		walk->stride = alg->co.chunksize;
+	else
+		walk->stride = alg->walksize;
+
 	return skcipher_walk_first(walk);
 }
 
@@ -616,6 +620,11 @@ int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
 	unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 	int err;
 
+	if (cipher->co.base.cra_type != &crypto_skcipher_type) {
+		err = crypto_lskcipher_setkey_sg(tfm, key, keylen);
+		goto out;
+	}
+
 	if (keylen < cipher->min_keysize || keylen > cipher->max_keysize)
 		return -EINVAL;
 
@@ -624,6 +633,7 @@ int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
 	else
 		err = cipher->setkey(tfm, key, keylen);
 
+out:
 	if (unlikely(err)) {
 		skcipher_set_needkey(tfm);
 		return err;
@@ -649,6 +659,8 @@ int crypto_skcipher_encrypt(struct skcipher_request *req)
 
 	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 		ret = -ENOKEY;
+	else if (alg->co.base.cra_type != &crypto_skcipher_type)
+		ret = crypto_lskcipher_encrypt_sg(req);
 	else
 		ret = alg->encrypt(req);
 
@@ -671,6 +683,8 @@ int crypto_skcipher_decrypt(struct skcipher_request *req)
 
 	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 		ret = -ENOKEY;
+	else if (alg->co.base.cra_type != &crypto_skcipher_type)
+		ret = crypto_lskcipher_decrypt_sg(req);
 	else
 		ret = alg->decrypt(req);
 
@@ -693,6 +707,9 @@ static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 
 	skcipher_set_needkey(skcipher);
 
+	if (tfm->__crt_alg->cra_type != &crypto_skcipher_type)
+		return crypto_init_lskcipher_ops_sg(tfm);
+
 	if (alg->exit)
 		skcipher->base.exit = crypto_skcipher_exit_tfm;
 
@@ -702,6 +719,14 @@ static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 	return 0;
 }
 
+static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
+{
+	if (alg->cra_type != &crypto_skcipher_type)
+		return sizeof(struct crypto_lskcipher *);
+
+	return crypto_alg_extsize(alg);
+}
+
 static void crypto_skcipher_free_instance(struct crypto_instance *inst)
 {
 	struct skcipher_instance *skcipher =
@@ -770,7 +795,7 @@ static int __maybe_unused crypto_skcipher_report_stat(
 }
 
 static const struct crypto_type crypto_skcipher_type = {
-	.extsize = crypto_alg_extsize,
+	.extsize = crypto_skcipher_extsize,
 	.init_tfm = crypto_skcipher_init_tfm,
 	.free = crypto_skcipher_free_instance,
 #ifdef CONFIG_PROC_FS
@@ -783,7 +808,7 @@ static const struct crypto_type crypto_skcipher_type = {
 	.report_stat = crypto_skcipher_report_stat,
 #endif
 	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
-	.maskset = CRYPTO_ALG_TYPE_MASK,
+	.maskset = CRYPTO_ALG_TYPE_SKCIPHER_MASK,
 	.type = CRYPTO_ALG_TYPE_SKCIPHER,
 	.tfmsize = offsetof(struct crypto_skcipher, base),
 };
@@ -834,23 +859,18 @@ int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask)
 }
 EXPORT_SYMBOL_GPL(crypto_has_skcipher);
 
-static int skcipher_prepare_alg(struct skcipher_alg *alg)
+int skcipher_prepare_alg_common(struct skcipher_alg_common *alg)
 {
-	struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
+	struct crypto_istat_cipher *istat = skcipher_get_stat_common(alg);
 	struct crypto_alg *base = &alg->base;
 
-	if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
-	    alg->walksize > PAGE_SIZE / 8)
+	if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8)
 		return -EINVAL;
 
 	if (!alg->chunksize)
 		alg->chunksize = base->cra_blocksize;
-	if (!alg->walksize)
-		alg->walksize = alg->chunksize;
 
-	base->cra_type = &crypto_skcipher_type;
 	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
-	base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
 
 	if (IS_ENABLED(CONFIG_CRYPTO_STATS))
 		memset(istat, 0, sizeof(*istat));
@@ -858,6 +878,27 @@ static int skcipher_prepare_alg(struct skcipher_alg *alg)
 	return 0;
 }
 
+static int skcipher_prepare_alg(struct skcipher_alg *alg)
+{
+	struct crypto_alg *base = &alg->base;
+	int err;
+
+	err = skcipher_prepare_alg_common(&alg->co);
+	if (err)
+		return err;
+
+	if (alg->walksize > PAGE_SIZE / 8)
+		return -EINVAL;
+
+	if (!alg->walksize)
+		alg->walksize = alg->chunksize;
+
+	base->cra_type = &crypto_skcipher_type;
+	base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
+
+	return 0;
+}
+
 int crypto_register_skcipher(struct skcipher_alg *alg)
 {
 	struct crypto_alg *base = &alg->base;

crypto/skcipher.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2023 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+#ifndef _LOCAL_CRYPTO_SKCIPHER_H
+#define _LOCAL_CRYPTO_SKCIPHER_H
+
+#include <crypto/internal/skcipher.h>
+#include "internal.h"
+
+static inline struct crypto_istat_cipher *skcipher_get_stat_common(
+	struct skcipher_alg_common *alg)
+{
+#ifdef CONFIG_CRYPTO_STATS
+	return &alg->stat;
+#else
+	return NULL;
+#endif
+}
+
+int crypto_lskcipher_setkey_sg(struct crypto_skcipher *tfm, const u8 *key,
+			       unsigned int keylen);
+int crypto_lskcipher_encrypt_sg(struct skcipher_request *req);
+int crypto_lskcipher_decrypt_sg(struct skcipher_request *req);
+int crypto_init_lskcipher_ops_sg(struct crypto_tfm *tfm);
+int skcipher_prepare_alg_common(struct skcipher_alg_common *alg);
+
+#endif	/* _LOCAL_CRYPTO_SKCIPHER_H */

include/crypto/internal/skcipher.h

@@ -36,10 +36,25 @@ struct skcipher_instance {
 	};
 };
 
+struct lskcipher_instance {
+	void (*free)(struct lskcipher_instance *inst);
+	union {
+		struct {
+			char head[offsetof(struct lskcipher_alg, co.base)];
+			struct crypto_instance base;
+		} s;
+		struct lskcipher_alg alg;
+	};
+};
+
 struct crypto_skcipher_spawn {
 	struct crypto_spawn base;
 };
 
+struct crypto_lskcipher_spawn {
+	struct crypto_spawn base;
+};
+
 struct skcipher_walk {
 	union {
 		struct {
@@ -80,6 +95,12 @@ static inline struct crypto_instance *skcipher_crypto_instance(
 	return &inst->s.base;
 }
 
+static inline struct crypto_instance *lskcipher_crypto_instance(
+	struct lskcipher_instance *inst)
+{
+	return &inst->s.base;
+}
+
 static inline struct skcipher_instance *skcipher_alg_instance(
 	struct crypto_skcipher *skcipher)
 {
@@ -87,11 +108,23 @@ static inline struct skcipher_instance *skcipher_alg_instance(
 			    struct skcipher_instance, alg);
 }
 
+static inline struct lskcipher_instance *lskcipher_alg_instance(
+	struct crypto_lskcipher *lskcipher)
+{
+	return container_of(crypto_lskcipher_alg(lskcipher),
+			    struct lskcipher_instance, alg);
+}
+
 static inline void *skcipher_instance_ctx(struct skcipher_instance *inst)
 {
 	return crypto_instance_ctx(skcipher_crypto_instance(inst));
 }
 
+static inline void *lskcipher_instance_ctx(struct lskcipher_instance *inst)
+{
+	return crypto_instance_ctx(lskcipher_crypto_instance(inst));
+}
+
 static inline void skcipher_request_complete(struct skcipher_request *req, int err)
 {
 	crypto_request_complete(&req->base, err);
@@ -101,29 +134,56 @@ int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
 			 struct crypto_instance *inst,
 			 const char *name, u32 type, u32 mask);
 
+int crypto_grab_lskcipher(struct crypto_lskcipher_spawn *spawn,
+			  struct crypto_instance *inst,
+			  const char *name, u32 type, u32 mask);
+
 static inline void crypto_drop_skcipher(struct crypto_skcipher_spawn *spawn)
 {
 	crypto_drop_spawn(&spawn->base);
 }
 
+static inline void crypto_drop_lskcipher(struct crypto_lskcipher_spawn *spawn)
+{
+	crypto_drop_spawn(&spawn->base);
+}
+
 static inline struct skcipher_alg *crypto_skcipher_spawn_alg(
 	struct crypto_skcipher_spawn *spawn)
 {
 	return container_of(spawn->base.alg, struct skcipher_alg, base);
 }
 
+static inline struct lskcipher_alg *crypto_lskcipher_spawn_alg(
+	struct crypto_lskcipher_spawn *spawn)
+{
+	return container_of(spawn->base.alg, struct lskcipher_alg, co.base);
+}
+
 static inline struct skcipher_alg *crypto_spawn_skcipher_alg(
 	struct crypto_skcipher_spawn *spawn)
 {
 	return crypto_skcipher_spawn_alg(spawn);
 }
 
+static inline struct lskcipher_alg *crypto_spawn_lskcipher_alg(
+	struct crypto_lskcipher_spawn *spawn)
+{
+	return crypto_lskcipher_spawn_alg(spawn);
+}
+
 static inline struct crypto_skcipher *crypto_spawn_skcipher(
 	struct crypto_skcipher_spawn *spawn)
 {
 	return crypto_spawn_tfm2(&spawn->base);
 }
 
+static inline struct crypto_lskcipher *crypto_spawn_lskcipher(
+	struct crypto_lskcipher_spawn *spawn)
+{
+	return crypto_spawn_tfm2(&spawn->base);
+}
+
 static inline void crypto_skcipher_set_reqsize(
 	struct crypto_skcipher *skcipher, unsigned int reqsize)
 {
@@ -144,6 +204,13 @@ void crypto_unregister_skciphers(struct skcipher_alg *algs, int count);
 int skcipher_register_instance(struct crypto_template *tmpl,
 			       struct skcipher_instance *inst);
 
+int crypto_register_lskcipher(struct lskcipher_alg *alg);
+void crypto_unregister_lskcipher(struct lskcipher_alg *alg);
+int crypto_register_lskciphers(struct lskcipher_alg *algs, int count);
+void crypto_unregister_lskciphers(struct lskcipher_alg *algs, int count);
+int lskcipher_register_instance(struct crypto_template *tmpl,
+				struct lskcipher_instance *inst);
+
 int skcipher_walk_done(struct skcipher_walk *walk, int err);
 int skcipher_walk_virt(struct skcipher_walk *walk,
 		       struct skcipher_request *req,
@@ -166,6 +233,11 @@ static inline void *crypto_skcipher_ctx(struct crypto_skcipher *tfm)
 	return crypto_tfm_ctx(&tfm->base);
 }
 
+static inline void *crypto_lskcipher_ctx(struct crypto_lskcipher *tfm)
+{
+	return crypto_tfm_ctx(&tfm->base);
+}
+
 static inline void *crypto_skcipher_ctx_dma(struct crypto_skcipher *tfm)
 {
 	return crypto_tfm_ctx_dma(&tfm->base);
@@ -209,21 +281,16 @@ static inline unsigned int crypto_skcipher_alg_walksize(
 	return alg->walksize;
 }
 
-/**
- * crypto_skcipher_walksize() - obtain walk size
- * @tfm: cipher handle
- *
- * In some cases, algorithms can only perform optimally when operating on
- * multiple blocks in parallel. This is reflected by the walksize, which
- * must be a multiple of the chunksize (or equal if the concern does not
- * apply)
- *
- * Return: walk size in bytes
- */
-static inline unsigned int crypto_skcipher_walksize(
-	struct crypto_skcipher *tfm)
+static inline unsigned int crypto_lskcipher_alg_min_keysize(
+	struct lskcipher_alg *alg)
+{
+	return alg->co.min_keysize;
+}
+
+static inline unsigned int crypto_lskcipher_alg_max_keysize(
+	struct lskcipher_alg *alg)
 {
-	return crypto_skcipher_alg_walksize(crypto_skcipher_alg(tfm));
+	return alg->co.max_keysize;
 }
 
 /* Helpers for simple block cipher modes of operation */
@@ -249,5 +316,24 @@ static inline struct crypto_alg *skcipher_ialg_simple(
 	return crypto_spawn_cipher_alg(spawn);
 }
 
+static inline struct crypto_lskcipher *lskcipher_cipher_simple(
+	struct crypto_lskcipher *tfm)
+{
+	struct crypto_lskcipher **ctx = crypto_lskcipher_ctx(tfm);
+
+	return *ctx;
+}
+
+struct lskcipher_instance *lskcipher_alloc_instance_simple(
+	struct crypto_template *tmpl, struct rtattr **tb);
+
+static inline struct lskcipher_alg *lskcipher_ialg_simple(
+	struct lskcipher_instance *inst)
+{
+	struct crypto_lskcipher_spawn *spawn = lskcipher_instance_ctx(inst);
+
+	return crypto_lskcipher_spawn_alg(spawn);
+}
+
 #endif	/* _CRYPTO_INTERNAL_SKCIPHER_H */
 

include/linux/crypto.h

@@ -24,6 +24,7 @@
 #define CRYPTO_ALG_TYPE_CIPHER		0x00000001
 #define CRYPTO_ALG_TYPE_COMPRESS	0x00000002
 #define CRYPTO_ALG_TYPE_AEAD		0x00000003
+#define CRYPTO_ALG_TYPE_LSKCIPHER	0x00000004
 #define CRYPTO_ALG_TYPE_SKCIPHER	0x00000005
 #define CRYPTO_ALG_TYPE_AKCIPHER	0x00000006
 #define CRYPTO_ALG_TYPE_SIG		0x00000007