commit 357d065a44cdd77ed5ff35155a989f2a763e96ef upstream. [backported: the VMX driver did not use crypto_simd_usable() until after 5.1]

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 ---

v2: do stable backport form correctly.

--- 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, }, };