diff mbox series

[v3,5/7] crypto: arm64/aes-neonbs - stop using SIMD helper for skciphers

Message ID 20210512184439.8778-6-ardb@kernel.org (mailing list archive)
State New, archived
Headers show
Series running kernel mode SIMD with softirqs disabled | expand

Commit Message

Ard Biesheuvel May 12, 2021, 6:44 p.m. UTC 
Calls into the skcipher API can only occur from contexts where the SIMD
unit is available, so there is no need for the SIMD helper.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/arm64/crypto/Kconfig           |   2 -
 arch/arm64/crypto/aes-neonbs-glue.c | 122 ++------------------
 2 files changed, 9 insertions(+), 115 deletions(-)

Comments

Eric Biggers May 12, 2021, 8:08 p.m. UTC | #1 
On Wed, May 12, 2021 at 08:44:37PM +0200, Ard Biesheuvel wrote:
> Calls into the skcipher API can only occur from contexts where the SIMD
> unit is available, so there is no need for the SIMD helper.
> 
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

It would be helpful if the commit message made it clear that "Calls into the
skcipher API can only occur from contexts where the SIMD unit is available" is
something that is now the case but wasn't the case previously.  Otherwise I
could see people backporting this patch without its prerequisites.

Likewise for some of the other patches in this patchset.

- Eric
Ard Biesheuvel May 12, 2021, 9:25 p.m. UTC | #2 
On Wed, 12 May 2021 at 22:08, Eric Biggers <ebiggers@kernel.org> wrote:
>
> On Wed, May 12, 2021 at 08:44:37PM +0200, Ard Biesheuvel wrote:
> > Calls into the skcipher API can only occur from contexts where the SIMD
> > unit is available, so there is no need for the SIMD helper.
> >
> > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
>
> It would be helpful if the commit message made it clear that "Calls into the
> skcipher API can only occur from contexts where the SIMD unit is available" is
> something that is now the case but wasn't the case previously.  Otherwise I
> could see people backporting this patch without its prerequisites.
>
> Likewise for some of the other patches in this patchset.
>

OK
diff mbox series

Patch

diff --git a/arch/arm64/crypto/Kconfig b/arch/arm64/crypto/Kconfig
index b8eb0453123d..ed1e8cadeb3a 100644
--- a/arch/arm64/crypto/Kconfig
+++ b/arch/arm64/crypto/Kconfig
@@ -122,8 +122,6 @@  config CRYPTO_AES_ARM64_BS
 	depends on KERNEL_MODE_NEON
 	select CRYPTO_SKCIPHER
 	select CRYPTO_AES_ARM64_NEON_BLK
-	select CRYPTO_AES_ARM64
 	select CRYPTO_LIB_AES
-	select CRYPTO_SIMD
 
 endif
diff --git a/arch/arm64/crypto/aes-neonbs-glue.c b/arch/arm64/crypto/aes-neonbs-glue.c
index fb507d569922..8df6ad8cb09d 100644
--- a/arch/arm64/crypto/aes-neonbs-glue.c
+++ b/arch/arm64/crypto/aes-neonbs-glue.c
@@ -63,11 +63,6 @@  struct aesbs_cbc_ctx {
 	u32			enc[AES_MAX_KEYLENGTH_U32];
 };
 
-struct aesbs_ctr_ctx {
-	struct aesbs_ctx	key;		/* must be first member */
-	struct crypto_aes_ctx	fallback;
-};
-
 struct aesbs_xts_ctx {
 	struct aesbs_ctx	key;
 	u32			twkey[AES_MAX_KEYLENGTH_U32];
@@ -207,25 +202,6 @@  static int cbc_decrypt(struct skcipher_request *req)
 	return err;
 }
 
-static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key,
-				 unsigned int key_len)
-{
-	struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
-	int err;
-
-	err = aes_expandkey(&ctx->fallback, in_key, key_len);
-	if (err)
-		return err;
-
-	ctx->key.rounds = 6 + key_len / 4;
-
-	kernel_neon_begin();
-	aesbs_convert_key(ctx->key.rk, ctx->fallback.key_enc, ctx->key.rounds);
-	kernel_neon_end();
-
-	return 0;
-}
-
 static int ctr_encrypt(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
@@ -292,29 +268,6 @@  static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
 	return aesbs_setkey(tfm, in_key, key_len);
 }
 
-static void ctr_encrypt_one(struct crypto_skcipher *tfm, const u8 *src, u8 *dst)
-{
-	struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
-	unsigned long flags;
-
-	/*
-	 * Temporarily disable interrupts to avoid races where
-	 * cachelines are evicted when the CPU is interrupted
-	 * to do something else.
-	 */
-	local_irq_save(flags);
-	aes_encrypt(&ctx->fallback, dst, src);
-	local_irq_restore(flags);
-}
-
-static int ctr_encrypt_sync(struct skcipher_request *req)
-{
-	if (!crypto_simd_usable())
-		return crypto_ctr_encrypt_walk(req, ctr_encrypt_one);
-
-	return ctr_encrypt(req);
-}
-
 static int __xts_crypt(struct skcipher_request *req, bool encrypt,
 		       void (*fn)(u8 out[], u8 const in[], u8 const rk[],
 				  int rounds, int blocks, u8 iv[]))
@@ -431,13 +384,12 @@  static int xts_decrypt(struct skcipher_request *req)
 }
 
 static struct skcipher_alg aes_algs[] = { {
-	.base.cra_name		= "__ecb(aes)",
-	.base.cra_driver_name	= "__ecb-aes-neonbs",
+	.base.cra_name		= "ecb(aes)",
+	.base.cra_driver_name	= "ecb-aes-neonbs",
 	.base.cra_priority	= 250,
 	.base.cra_blocksize	= AES_BLOCK_SIZE,
 	.base.cra_ctxsize	= sizeof(struct aesbs_ctx),
 	.base.cra_module	= THIS_MODULE,
-	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
 
 	.min_keysize		= AES_MIN_KEY_SIZE,
 	.max_keysize		= AES_MAX_KEY_SIZE,
@@ -446,13 +398,12 @@  static struct skcipher_alg aes_algs[] = { {
 	.encrypt		= ecb_encrypt,
 	.decrypt		= ecb_decrypt,
 }, {
-	.base.cra_name		= "__cbc(aes)",
-	.base.cra_driver_name	= "__cbc-aes-neonbs",
+	.base.cra_name		= "cbc(aes)",
+	.base.cra_driver_name	= "cbc-aes-neonbs",
 	.base.cra_priority	= 250,
 	.base.cra_blocksize	= AES_BLOCK_SIZE,
 	.base.cra_ctxsize	= sizeof(struct aesbs_cbc_ctx),
 	.base.cra_module	= THIS_MODULE,
-	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
 
 	.min_keysize		= AES_MIN_KEY_SIZE,
 	.max_keysize		= AES_MAX_KEY_SIZE,
@@ -462,13 +413,12 @@  static struct skcipher_alg aes_algs[] = { {
 	.encrypt		= cbc_encrypt,
 	.decrypt		= cbc_decrypt,
 }, {
-	.base.cra_name		= "__ctr(aes)",
-	.base.cra_driver_name	= "__ctr-aes-neonbs",
+	.base.cra_name		= "ctr(aes)",
+	.base.cra_driver_name	= "ctr-aes-neonbs",
 	.base.cra_priority	= 250,
 	.base.cra_blocksize	= 1,
 	.base.cra_ctxsize	= sizeof(struct aesbs_ctx),
 	.base.cra_module	= THIS_MODULE,
-	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
 
 	.min_keysize		= AES_MIN_KEY_SIZE,
 	.max_keysize		= AES_MAX_KEY_SIZE,
@@ -479,29 +429,12 @@  static struct skcipher_alg aes_algs[] = { {
 	.encrypt		= ctr_encrypt,
 	.decrypt		= ctr_encrypt,
 }, {
-	.base.cra_name		= "ctr(aes)",
-	.base.cra_driver_name	= "ctr-aes-neonbs",
-	.base.cra_priority	= 250 - 1,
-	.base.cra_blocksize	= 1,
-	.base.cra_ctxsize	= sizeof(struct aesbs_ctr_ctx),
-	.base.cra_module	= THIS_MODULE,
-
-	.min_keysize		= AES_MIN_KEY_SIZE,
-	.max_keysize		= AES_MAX_KEY_SIZE,
-	.chunksize		= AES_BLOCK_SIZE,
-	.walksize		= 8 * AES_BLOCK_SIZE,
-	.ivsize			= AES_BLOCK_SIZE,
-	.setkey			= aesbs_ctr_setkey_sync,
-	.encrypt		= ctr_encrypt_sync,
-	.decrypt		= ctr_encrypt_sync,
-}, {
-	.base.cra_name		= "__xts(aes)",
-	.base.cra_driver_name	= "__xts-aes-neonbs",
+	.base.cra_name		= "xts(aes)",
+	.base.cra_driver_name	= "xts-aes-neonbs",
 	.base.cra_priority	= 250,
 	.base.cra_blocksize	= AES_BLOCK_SIZE,
 	.base.cra_ctxsize	= sizeof(struct aesbs_xts_ctx),
 	.base.cra_module	= THIS_MODULE,
-	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
 
 	.min_keysize		= 2 * AES_MIN_KEY_SIZE,
 	.max_keysize		= 2 * AES_MAX_KEY_SIZE,
@@ -512,54 +445,17 @@  static struct skcipher_alg aes_algs[] = { {
 	.decrypt		= xts_decrypt,
 } };
 
-static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
-
 static void aes_exit(void)
 {
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(aes_simd_algs); i++)
-		if (aes_simd_algs[i])
-			simd_skcipher_free(aes_simd_algs[i]);
-
 	crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 }
 
 static int __init aes_init(void)
 {
-	struct simd_skcipher_alg *simd;
-	const char *basename;
-	const char *algname;
-	const char *drvname;
-	int err;
-	int i;
-
 	if (!cpu_have_named_feature(ASIMD))
 		return -ENODEV;
 
-	err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
-	if (err)
-		return err;
-
-	for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
-		if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
-			continue;
-
-		algname = aes_algs[i].base.cra_name + 2;
-		drvname = aes_algs[i].base.cra_driver_name + 2;
-		basename = aes_algs[i].base.cra_driver_name;
-		simd = simd_skcipher_create_compat(algname, drvname, basename);
-		err = PTR_ERR(simd);
-		if (IS_ERR(simd))
-			goto unregister_simds;
-
-		aes_simd_algs[i] = simd;
-	}
-	return 0;
-
-unregister_simds:
-	aes_exit();
-	return err;
+	return crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
 }
 
 module_init(aes_init);