Christophe Leroy christophe.leroy@c-s.fr writes:

Daniel Axtens dja@axtens.net a écrit :

Hi

I think you have to mention the upstream commit Id when submitting a patch to stable, see https://elixir.bootlin.com/linux/v5.2-rc1/source/Documentation/process/stabl...

Argh, right, sorry, still in Canonical Stable Release Update mode:

...

(backported from commit 357d065a44cdd77ed5ff35155a989f2a763e96ef)

I'll do a backport v2 with the correct format.

Regards, Daniel

Christophe

...

VMX ghash was using a fallback that did not support interleaving simd and nosimd operations, leading to failures in the extended test suite.

If I understood correctly, Eric's suggestion was to use the same data format that the generic code uses, allowing us to call into it with the same contexts. I wasn't able to get that to work - I think there's a very different key structure and data layout being used.

So instead steal the arm64 approach and perform the fallback operations directly if required.

Fixes: cc333cd68dfa ("crypto: vmx - Adding GHASH routines for VMX module") Cc: stable@vger.kernel.org # v4.1+ Reported-by: Eric Biggers ebiggers@google.com Signed-off-by: Daniel Axtens dja@axtens.net Acked-by: Ard Biesheuvel ard.biesheuvel@linaro.org Tested-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Herbert Xu herbert@gondor.apana.org.au

...

Signed-off-by: Daniel Axtens dja@axtens.net

drivers/crypto/vmx/ghash.c | 212 +++++++++++++++---------------------- 1 file changed, 86 insertions(+), 126 deletions(-)

diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c index dd8b8716467a..2d1a8cd35509 100644 --- a/drivers/crypto/vmx/ghash.c +++ b/drivers/crypto/vmx/ghash.c @@ -1,22 +1,14 @@ +// SPDX-License-Identifier: GPL-2.0 /**

• GHASH routines supporting VMX instructions on the Power 8

• • Copyright (C) 2015 International Business Machines Inc.
• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License as published by
• • the Free Software Foundation; version 2 only.
• • This program is distributed in the hope that it will be useful,
• • but WITHOUT ANY WARRANTY; without even the implied warranty of
• • MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
• • GNU General Public License for more details.
• • You should have received a copy of the GNU General Public License
• • along with this program; if not, write to the Free Software
• • Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

• • Copyright (C) 2015, 2019 International Business Machines Inc.
  • Author: Marcelo Henrique Cerri mhcerri@br.ibm.com
• • Extended by Daniel Axtens dja@axtens.net to replace the fallback
• • mechanism. The new approach is based on arm64 code, which is:
• • Copyright (C) 2014 - 2018 Linaro Ltd. ard.biesheuvel@linaro.org
  */

#include <linux/types.h> @@ -39,71 +31,25 @@ void gcm_ghash_p8(u64 Xi[2], const u128 htable[16], const u8 *in, size_t len);

struct p8_ghash_ctx {

• /* key used by vector asm */ u128 htable[16];

• struct crypto_shash *fallback;

• /* key used by software fallback */
• be128 key;

};

struct p8_ghash_desc_ctx { u64 shash[2]; u8 buffer[GHASH_DIGEST_SIZE]; int bytes;

• struct shash_desc fallback_desc;

};

-static int p8_ghash_init_tfm(struct crypto_tfm *tfm) -{

• const char *alg = "ghash-generic";
• struct crypto_shash *fallback;
• struct crypto_shash *shash_tfm = __crypto_shash_cast(tfm);
• struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
• fallback = crypto_alloc_shash(alg, 0, CRYPTO_ALG_NEED_FALLBACK);
• if (IS_ERR(fallback)) {

• printk(KERN_ERR
  

•        "Failed to allocate transformation for '%s': %ld\n",
  

•        alg, PTR_ERR(fallback));
  

• return PTR_ERR(fallback);
  

• }
• crypto_shash_set_flags(fallback,

• 	       crypto_shash_get_flags((struct crypto_shash
  

• 				       *) tfm));
  

• /* Check if the descsize defined in the algorithm is still enough. */
• if (shash_tfm->descsize < sizeof(struct p8_ghash_desc_ctx)

•    + crypto_shash_descsize(fallback)) {
  

• printk(KERN_ERR
  

•        "Desc size of the fallback implementation (%s) does not  
  

match the expected value: %lu vs %u\n",

•        alg,
  

•        shash_tfm->descsize - sizeof(struct p8_ghash_desc_ctx),
  

•        crypto_shash_descsize(fallback));
  

• return -EINVAL;
  

• }
• ctx->fallback = fallback;
• return 0;

-}

-static void p8_ghash_exit_tfm(struct crypto_tfm *tfm) -{

• struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
• if (ctx->fallback) {

• crypto_free_shash(ctx->fallback);
  

• ctx->fallback = NULL;
  

• }

-}

static int p8_ghash_init(struct shash_desc *desc) {

• struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm)); struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);

  dctx->bytes = 0; memset(dctx->shash, 0, GHASH_DIGEST_SIZE);

• dctx->fallback_desc.tfm = ctx->fallback;

• dctx->fallback_desc.flags = desc->flags;

• return crypto_shash_init(&dctx->fallback_desc);

• return 0;

}

static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key, @@ -121,7 +67,51 @@ static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key, disable_kernel_vsx(); pagefault_enable(); preempt_enable();

• return crypto_shash_setkey(ctx->fallback, key, keylen);

• memcpy(&ctx->key, key, GHASH_BLOCK_SIZE);
• return 0;

+}

+static inline void __ghash_block(struct p8_ghash_ctx *ctx,

• 		 struct p8_ghash_desc_ctx *dctx)
  

+{

• if (!IN_INTERRUPT) {

• preempt_disable();
  

• pagefault_disable();
  

• enable_kernel_vsx();
  

• gcm_ghash_p8(dctx->shash, ctx->htable,
  

• 		dctx->buffer, GHASH_DIGEST_SIZE);
  

• disable_kernel_vsx();
  

• pagefault_enable();
  

• preempt_enable();
  

• } else {

• crypto_xor((u8 *)dctx->shash, dctx->buffer, GHASH_BLOCK_SIZE);
  

• gf128mul_lle((be128 *)dctx->shash, &ctx->key);
  

• }

+}

+static inline void __ghash_blocks(struct p8_ghash_ctx *ctx,

• 		  struct p8_ghash_desc_ctx *dctx,
  

• 		  const u8 *src, unsigned int srclen)
  

+{

• if (!IN_INTERRUPT) {

• preempt_disable();
  

• pagefault_disable();
  

• enable_kernel_vsx();
  

• gcm_ghash_p8(dctx->shash, ctx->htable,
  

• 		src, srclen);
  

• disable_kernel_vsx();
  

• pagefault_enable();
  

• preempt_enable();
  

• } else {

• while (srclen >= GHASH_BLOCK_SIZE) {
  

• 	crypto_xor((u8 *)dctx->shash, src, GHASH_BLOCK_SIZE);
  

• 	gf128mul_lle((be128 *)dctx->shash, &ctx->key);
  

• 	srclen -= GHASH_BLOCK_SIZE;
  

• 	src += GHASH_BLOCK_SIZE;
  

• }
  

• }

}

static int p8_ghash_update(struct shash_desc *desc, @@ -131,49 +121,33 @@ static int p8_ghash_update(struct shash_desc *desc, struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm)); struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);

• if (IN_INTERRUPT) {

• return crypto_shash_update(&dctx->fallback_desc, src,
  

• 			   srclen);
  

• } else {

• if (dctx->bytes) {
  

• 	if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) {
  

• 		memcpy(dctx->buffer + dctx->bytes, src,
  

• 		       srclen);
  

• 		dctx->bytes += srclen;
  

• 		return 0;
  

• 	}
  

• if (dctx->bytes) {

• if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) {
  memcpy(dctx->buffer + dctx->bytes, src,
  

• 	       GHASH_DIGEST_SIZE - dctx->bytes);
  

• 	preempt_disable();
  

• 	pagefault_disable();
  

• 	enable_kernel_vsx();
  

• 	gcm_ghash_p8(dctx->shash, ctx->htable,
  

• 		     dctx->buffer, GHASH_DIGEST_SIZE);
  

• 	disable_kernel_vsx();
  

• 	pagefault_enable();
  

• 	preempt_enable();
  

• 	src += GHASH_DIGEST_SIZE - dctx->bytes;
  

• 	srclen -= GHASH_DIGEST_SIZE - dctx->bytes;
  

• 	dctx->bytes = 0;
  

• }
  

• len = srclen & ~(GHASH_DIGEST_SIZE - 1);
  

• if (len) {
  

• 	preempt_disable();
  

• 	pagefault_disable();
  

• 	enable_kernel_vsx();
  

• 	gcm_ghash_p8(dctx->shash, ctx->htable, src, len);
  

• 	disable_kernel_vsx();
  

• 	pagefault_enable();
  

• 	preempt_enable();
  

• 	src += len;
  

• 	srclen -= len;
  

• }
  

• if (srclen) {
  

• 	memcpy(dctx->buffer, src, srclen);
  

• 	dctx->bytes = srclen;
  

• 		srclen);
  

• 	dctx->bytes += srclen;
  

• 	return 0;
  

  }

• return 0;
  

• memcpy(dctx->buffer + dctx->bytes, src,
  

• 	GHASH_DIGEST_SIZE - dctx->bytes);
  

• __ghash_block(ctx, dctx);
  

• src += GHASH_DIGEST_SIZE - dctx->bytes;
  

• srclen -= GHASH_DIGEST_SIZE - dctx->bytes;
  

• dctx->bytes = 0;
  

• }
• len = srclen & ~(GHASH_DIGEST_SIZE - 1);
• if (len) {

• __ghash_blocks(ctx, dctx, src, len);
  

• src += len;
  

• srclen -= len;
  

  }
• if (srclen) {

• memcpy(dctx->buffer, src, srclen);
  

• dctx->bytes = srclen;
  

• }
• return 0;

}

static int p8_ghash_final(struct shash_desc *desc, u8 *out) @@ -182,25 +156,14 @@ static int p8_ghash_final(struct shash_desc *desc, u8 *out) struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm)); struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);

• if (IN_INTERRUPT) {

• return crypto_shash_final(&dctx->fallback_desc, out);
  

• } else {

• if (dctx->bytes) {
  

• 	for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++)
  

• 		dctx->buffer[i] = 0;
  

• 	preempt_disable();
  

• 	pagefault_disable();
  

• 	enable_kernel_vsx();
  

• 	gcm_ghash_p8(dctx->shash, ctx->htable,
  

• 		     dctx->buffer, GHASH_DIGEST_SIZE);
  

• 	disable_kernel_vsx();
  

• 	pagefault_enable();
  

• 	preempt_enable();
  

• 	dctx->bytes = 0;
  

• }
  

• memcpy(out, dctx->shash, GHASH_DIGEST_SIZE);
  

• return 0;
  

• if (dctx->bytes) {

• for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++)
  

• 	dctx->buffer[i] = 0;
  

• __ghash_block(ctx, dctx);
  

• dctx->bytes = 0;
  

  }
• memcpy(out, dctx->shash, GHASH_DIGEST_SIZE);
• return 0;

}

struct shash_alg p8_ghash_alg = { @@ -215,11 +178,8 @@ struct shash_alg p8_ghash_alg = { .cra_name = "ghash", .cra_driver_name = "p8_ghash", .cra_priority = 1000,

•  .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
  

  .cra_blocksize = GHASH_BLOCK_SIZE, .cra_ctxsize = sizeof(struct p8_ghash_ctx), .cra_module = THIS_MODULE,

•  .cra_init = p8_ghash_init_tfm,
  

•  .cra_exit = p8_ghash_exit_tfm,
  

  },

};

2.19.1