queue-5.1/crypto-vmx-ghash-do-nosimd-fallback-manually.patch

   1 From 357d065a44cdd77ed5ff35155a989f2a763e96ef Mon Sep 17 00:00:00 2001
   2 From: Daniel Axtens <dja@axtens.net>
   3 Date: Fri, 17 May 2019 01:40:02 +1000
   4 Subject: crypto: vmx - ghash: do nosimd fallback manually
   5
   6 From: Daniel Axtens <dja@axtens.net>
   7
   8 commit 357d065a44cdd77ed5ff35155a989f2a763e96ef upstream.
   9
  10 VMX ghash was using a fallback that did not support interleaving simd
  11 and nosimd operations, leading to failures in the extended test suite.
  12
  13 If I understood correctly, Eric's suggestion was to use the same
  14 data format that the generic code uses, allowing us to call into it
  15 with the same contexts. I wasn't able to get that to work - I think
  16 there's a very different key structure and data layout being used.
  17
  18 So instead steal the arm64 approach and perform the fallback
  19 operations directly if required.
  20
  21 Fixes: cc333cd68dfa ("crypto: vmx - Adding GHASH routines for VMX module")
  22 Cc: stable@vger.kernel.org # v4.1+
  23 Reported-by: Eric Biggers <ebiggers@google.com>
  24 Signed-off-by: Daniel Axtens <dja@axtens.net>
  25 Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
  26 Tested-by: Michael Ellerman <mpe@ellerman.id.au>
  27 Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
  28 Signed-off-by: Daniel Axtens <dja@axtens.net>
  29 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  30
  31 ---
  32  drivers/crypto/vmx/ghash.c |  212 ++++++++++++++++++---------------------------
  33  1 file changed, 86 insertions(+), 126 deletions(-)
  34
  35 --- a/drivers/crypto/vmx/ghash.c
  36 +++ b/drivers/crypto/vmx/ghash.c
  37 @@ -1,22 +1,14 @@
  38 +// SPDX-License-Identifier: GPL-2.0
  39  /**
  40   * GHASH routines supporting VMX instructions on the Power 8
  41   *
  42 - * Copyright (C) 2015 International Business Machines Inc.
  43 - *
  44 - * This program is free software; you can redistribute it and/or modify
  45 - * it under the terms of the GNU General Public License as published by
  46 - * the Free Software Foundation; version 2 only.
  47 - *
  48 - * This program is distributed in the hope that it will be useful,
  49 - * but WITHOUT ANY WARRANTY; without even the implied warranty of
  50 - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  51 - * GNU General Public License for more details.
  52 - *
  53 - * You should have received a copy of the GNU General Public License
  54 - * along with this program; if not, write to the Free Software
  55 - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  56 + * Copyright (C) 2015, 2019 International Business Machines Inc.
  57   *
  58   * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com>
  59 + *
  60 + * Extended by Daniel Axtens <dja@axtens.net> to replace the fallback
  61 + * mechanism. The new approach is based on arm64 code, which is:
  62 + *   Copyright (C) 2014 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org>
  63   */
  64
  65  #include <linux/types.h>
  66 @@ -39,71 +31,25 @@ void gcm_ghash_p8(u64 Xi[2], const u128
  67                   const u8 *in, size_t len);
  68
  69  struct p8_ghash_ctx {
  70 +       /* key used by vector asm */
  71         u128 htable[16];
  72 -       struct crypto_shash *fallback;
  73 +       /* key used by software fallback */
  74 +       be128 key;
  75  };
  76
  77  struct p8_ghash_desc_ctx {
  78         u64 shash[2];
  79         u8 buffer[GHASH_DIGEST_SIZE];
  80         int bytes;
  81 -       struct shash_desc fallback_desc;
  82  };
  83
  84 -static int p8_ghash_init_tfm(struct crypto_tfm *tfm)
  85 -{
  86 -       const char *alg = "ghash-generic";
  87 -       struct crypto_shash *fallback;
  88 -       struct crypto_shash *shash_tfm = __crypto_shash_cast(tfm);
  89 -       struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
  90 -
  91 -       fallback = crypto_alloc_shash(alg, 0, CRYPTO_ALG_NEED_FALLBACK);
  92 -       if (IS_ERR(fallback)) {
  93 -               printk(KERN_ERR
  94 -                      "Failed to allocate transformation for '%s': %ld\n",
  95 -                      alg, PTR_ERR(fallback));
  96 -               return PTR_ERR(fallback);
  97 -       }
  98 -
  99 -       crypto_shash_set_flags(fallback,
 100 -                              crypto_shash_get_flags((struct crypto_shash
 101 -                                                      *) tfm));
 102 -
 103 -       /* Check if the descsize defined in the algorithm is still enough. */
 104 -       if (shash_tfm->descsize < sizeof(struct p8_ghash_desc_ctx)
 105 -           + crypto_shash_descsize(fallback)) {
 106 -               printk(KERN_ERR
 107 -                      "Desc size of the fallback implementation (%s) does not match the expected value: %lu vs %u\n",
 108 -                      alg,
 109 -                      shash_tfm->descsize - sizeof(struct p8_ghash_desc_ctx),
 110 -                      crypto_shash_descsize(fallback));
 111 -               return -EINVAL;
 112 -       }
 113 -       ctx->fallback = fallback;
 114 -
 115 -       return 0;
 116 -}
 117 -
 118 -static void p8_ghash_exit_tfm(struct crypto_tfm *tfm)
 119 -{
 120 -       struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
 121 -
 122 -       if (ctx->fallback) {
 123 -               crypto_free_shash(ctx->fallback);
 124 -               ctx->fallback = NULL;
 125 -       }
 126 -}
 127 -
 128  static int p8_ghash_init(struct shash_desc *desc)
 129  {
 130 -       struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
 131         struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 132
 133         dctx->bytes = 0;
 134         memset(dctx->shash, 0, GHASH_DIGEST_SIZE);
 135 -       dctx->fallback_desc.tfm = ctx->fallback;
 136 -       dctx->fallback_desc.flags = desc->flags;
 137 -       return crypto_shash_init(&dctx->fallback_desc);
 138 +       return 0;
 139  }
 140
 141  static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key,
 142 @@ -121,7 +67,51 @@ static int p8_ghash_setkey(struct crypto
 143         disable_kernel_vsx();
 144         pagefault_enable();
 145         preempt_enable();
 146 -       return crypto_shash_setkey(ctx->fallback, key, keylen);
 147 +
 148 +       memcpy(&ctx->key, key, GHASH_BLOCK_SIZE);
 149 +
 150 +       return 0;
 151 +}
 152 +
 153 +static inline void __ghash_block(struct p8_ghash_ctx *ctx,
 154 +                                struct p8_ghash_desc_ctx *dctx)
 155 +{
 156 +       if (!IN_INTERRUPT) {
 157 +               preempt_disable();
 158 +               pagefault_disable();
 159 +               enable_kernel_vsx();
 160 +               gcm_ghash_p8(dctx->shash, ctx->htable,
 161 +                               dctx->buffer, GHASH_DIGEST_SIZE);
 162 +               disable_kernel_vsx();
 163 +               pagefault_enable();
 164 +               preempt_enable();
 165 +       } else {
 166 +               crypto_xor((u8 *)dctx->shash, dctx->buffer, GHASH_BLOCK_SIZE);
 167 +               gf128mul_lle((be128 *)dctx->shash, &ctx->key);
 168 +       }
 169 +}
 170 +
 171 +static inline void __ghash_blocks(struct p8_ghash_ctx *ctx,
 172 +                                 struct p8_ghash_desc_ctx *dctx,
 173 +                                 const u8 *src, unsigned int srclen)
 174 +{
 175 +       if (!IN_INTERRUPT) {
 176 +               preempt_disable();
 177 +               pagefault_disable();
 178 +               enable_kernel_vsx();
 179 +               gcm_ghash_p8(dctx->shash, ctx->htable,
 180 +                               src, srclen);
 181 +               disable_kernel_vsx();
 182 +               pagefault_enable();
 183 +               preempt_enable();
 184 +       } else {
 185 +               while (srclen >= GHASH_BLOCK_SIZE) {
 186 +                       crypto_xor((u8 *)dctx->shash, src, GHASH_BLOCK_SIZE);
 187 +                       gf128mul_lle((be128 *)dctx->shash, &ctx->key);
 188 +                       srclen -= GHASH_BLOCK_SIZE;
 189 +                       src += GHASH_BLOCK_SIZE;
 190 +               }
 191 +       }
 192  }
 193
 194  static int p8_ghash_update(struct shash_desc *desc,
 195 @@ -131,49 +121,33 @@ static int p8_ghash_update(struct shash_
 196         struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
 197         struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 198
 199 -       if (IN_INTERRUPT) {
 200 -               return crypto_shash_update(&dctx->fallback_desc, src,
 201 -                                          srclen);
 202 -       } else {
 203 -               if (dctx->bytes) {
 204 -                       if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) {
 205 -                               memcpy(dctx->buffer + dctx->bytes, src,
 206 -                                      srclen);
 207 -                               dctx->bytes += srclen;
 208 -                               return 0;
 209 -                       }
 210 +       if (dctx->bytes) {
 211 +               if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) {
 212                         memcpy(dctx->buffer + dctx->bytes, src,
 213 -                              GHASH_DIGEST_SIZE - dctx->bytes);
 214 -                       preempt_disable();
 215 -                       pagefault_disable();
 216 -                       enable_kernel_vsx();
 217 -                       gcm_ghash_p8(dctx->shash, ctx->htable,
 218 -                                    dctx->buffer, GHASH_DIGEST_SIZE);
 219 -                       disable_kernel_vsx();
 220 -                       pagefault_enable();
 221 -                       preempt_enable();
 222 -                       src += GHASH_DIGEST_SIZE - dctx->bytes;
 223 -                       srclen -= GHASH_DIGEST_SIZE - dctx->bytes;
 224 -                       dctx->bytes = 0;
 225 +                               srclen);
 226 +                       dctx->bytes += srclen;
 227 +                       return 0;
 228                 }
 229 -               len = srclen & ~(GHASH_DIGEST_SIZE - 1);
 230 -               if (len) {
 231 -                       preempt_disable();
 232 -                       pagefault_disable();
 233 -                       enable_kernel_vsx();
 234 -                       gcm_ghash_p8(dctx->shash, ctx->htable, src, len);
 235 -                       disable_kernel_vsx();
 236 -                       pagefault_enable();
 237 -                       preempt_enable();
 238 -                       src += len;
 239 -                       srclen -= len;
 240 -               }
 241 -               if (srclen) {
 242 -                       memcpy(dctx->buffer, src, srclen);
 243 -                       dctx->bytes = srclen;
 244 -               }
 245 -               return 0;
 246 +               memcpy(dctx->buffer + dctx->bytes, src,
 247 +                       GHASH_DIGEST_SIZE - dctx->bytes);
 248 +
 249 +               __ghash_block(ctx, dctx);
 250 +
 251 +               src += GHASH_DIGEST_SIZE - dctx->bytes;
 252 +               srclen -= GHASH_DIGEST_SIZE - dctx->bytes;
 253 +               dctx->bytes = 0;
 254 +       }
 255 +       len = srclen & ~(GHASH_DIGEST_SIZE - 1);
 256 +       if (len) {
 257 +               __ghash_blocks(ctx, dctx, src, len);
 258 +               src += len;
 259 +               srclen -= len;
 260         }
 261 +       if (srclen) {
 262 +               memcpy(dctx->buffer, src, srclen);
 263 +               dctx->bytes = srclen;
 264 +       }
 265 +       return 0;
 266  }
 267
 268  static int p8_ghash_final(struct shash_desc *desc, u8 *out)
 269 @@ -182,25 +156,14 @@ static int p8_ghash_final(struct shash_d
 270         struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
 271         struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 272
 273 -       if (IN_INTERRUPT) {
 274 -               return crypto_shash_final(&dctx->fallback_desc, out);
 275 -       } else {
 276 -               if (dctx->bytes) {
 277 -                       for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++)
 278 -                               dctx->buffer[i] = 0;
 279 -                       preempt_disable();
 280 -                       pagefault_disable();
 281 -                       enable_kernel_vsx();
 282 -                       gcm_ghash_p8(dctx->shash, ctx->htable,
 283 -                                    dctx->buffer, GHASH_DIGEST_SIZE);
 284 -                       disable_kernel_vsx();
 285 -                       pagefault_enable();
 286 -                       preempt_enable();
 287 -                       dctx->bytes = 0;
 288 -               }
 289 -               memcpy(out, dctx->shash, GHASH_DIGEST_SIZE);
 290 -               return 0;
 291 +       if (dctx->bytes) {
 292 +               for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++)
 293 +                       dctx->buffer[i] = 0;
 294 +               __ghash_block(ctx, dctx);
 295 +               dctx->bytes = 0;
 296         }
 297 +       memcpy(out, dctx->shash, GHASH_DIGEST_SIZE);
 298 +       return 0;
 299  }
 300
 301  struct shash_alg p8_ghash_alg = {
 302 @@ -215,11 +178,8 @@ struct shash_alg p8_ghash_alg = {
 303                  .cra_name = "ghash",
 304                  .cra_driver_name = "p8_ghash",
 305                  .cra_priority = 1000,
 306 -                .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
 307                  .cra_blocksize = GHASH_BLOCK_SIZE,
 308                  .cra_ctxsize = sizeof(struct p8_ghash_ctx),
 309                  .cra_module = THIS_MODULE,
 310 -                .cra_init = p8_ghash_init_tfm,
 311 -                .cra_exit = p8_ghash_exit_tfm,
 312         },
 313  };