drivers/crypto/nx/nx-sha256.c

   1 /**
   2  * SHA-256 routines supporting the Power 7+ Nest Accelerators driver
   3  *
   4  * Copyright (C) 2011-2012 International Business Machines Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 only.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  *
  19  * Author: Kent Yoder <yoder1@us.ibm.com>
  20  */
  21
  22 #include <crypto/internal/hash.h>
  23 #include <crypto/sha.h>
  24 #include <linux/module.h>
  25 #include <asm/vio.h>
  26 #include <asm/byteorder.h>
  27
  28 #include "nx_csbcpb.h"
  29 #include "nx.h"
  30
  31
  32 static int nx_crypto_ctx_sha256_init(struct crypto_tfm *tfm)
  33 {
  34         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
  35         int err;
  36
  37         err = nx_crypto_ctx_sha_init(tfm);
  38         if (err)
  39                 return err;
  40
  41         nx_ctx_init(nx_ctx, HCOP_FC_SHA);
  42
  43         nx_ctx->ap = &nx_ctx->props[NX_PROPS_SHA256];
  44
  45         NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
  46
  47         return 0;
  48 }
  49
  50 static int nx_sha256_init(struct shash_desc *desc) {
  51         struct sha256_state *sctx = shash_desc_ctx(desc);
  52
  53         memset(sctx, 0, sizeof *sctx);
  54
  55         sctx->state[0] = __cpu_to_be32(SHA256_H0);
  56         sctx->state[1] = __cpu_to_be32(SHA256_H1);
  57         sctx->state[2] = __cpu_to_be32(SHA256_H2);
  58         sctx->state[3] = __cpu_to_be32(SHA256_H3);
  59         sctx->state[4] = __cpu_to_be32(SHA256_H4);
  60         sctx->state[5] = __cpu_to_be32(SHA256_H5);
  61         sctx->state[6] = __cpu_to_be32(SHA256_H6);
  62         sctx->state[7] = __cpu_to_be32(SHA256_H7);
  63         sctx->count = 0;
  64
  65         return 0;
  66 }
  67
  68 static int nx_sha256_update(struct shash_desc *desc, const u8 *data,
  69                             unsigned int len)
  70 {
  71         struct sha256_state *sctx = shash_desc_ctx(desc);
  72         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
  73         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
  74         struct nx_sg *out_sg;
  75         u64 to_process = 0, leftover, total;
  76         unsigned long irq_flags;
  77         int rc = 0;
  78         int data_len;
  79         u32 max_sg_len;
  80         u64 buf_len = (sctx->count % SHA256_BLOCK_SIZE);
  81
  82         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  83
  84         /* 2 cases for total data len:
  85          *  1: < SHA256_BLOCK_SIZE: copy into state, return 0
  86          *  2: >= SHA256_BLOCK_SIZE: process X blocks, copy in leftover
  87          */
  88         total = (sctx->count % SHA256_BLOCK_SIZE) + len;
  89         if (total < SHA256_BLOCK_SIZE) {
  90                 memcpy(sctx->buf + buf_len, data, len);
  91                 sctx->count += len;
  92                 goto out;
  93         }
  94
  95         memcpy(csbcpb->cpb.sha256.message_digest, sctx->state, SHA256_DIGEST_SIZE);
  96         NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
  97         NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
  98
  99         max_sg_len = min_t(u64, nx_ctx->ap->sglen,
 100                         nx_driver.of.max_sg_len/sizeof(struct nx_sg));
 101         max_sg_len = min_t(u64, max_sg_len,
 102                         nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 103
 104         data_len = SHA256_DIGEST_SIZE;
 105         out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
 106                                   &data_len, max_sg_len);
 107         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 108
 109         if (data_len != SHA256_DIGEST_SIZE) {
 110                 rc = -EINVAL;
 111                 goto out;
 112         }
 113
 114         do {
 115                 int used_sgs = 0;
 116                 struct nx_sg *in_sg = nx_ctx->in_sg;
 117
 118                 if (buf_len) {
 119                         data_len = buf_len;
 120                         in_sg = nx_build_sg_list(in_sg,
 121                                                  (u8 *) sctx->buf,
 122                                                  &data_len,
 123                                                  max_sg_len);
 124
 125                         if (data_len != buf_len) {
 126                                 rc = -EINVAL;
 127                                 goto out;
 128                         }
 129                         used_sgs = in_sg - nx_ctx->in_sg;
 130                 }
 131
 132                 /* to_process: SHA256_BLOCK_SIZE aligned chunk to be
 133                  * processed in this iteration. This value is restricted
 134                  * by sg list limits and number of sgs we already used
 135                  * for leftover data. (see above)
 136                  * In ideal case, we could allow NX_PAGE_SIZE * max_sg_len,
 137                  * but because data may not be aligned, we need to account
 138                  * for that too. */
 139                 to_process = min_t(u64, total,
 140                         (max_sg_len - 1 - used_sgs) * NX_PAGE_SIZE);
 141                 to_process = to_process & ~(SHA256_BLOCK_SIZE - 1);
 142
 143                 data_len = to_process - buf_len;
 144                 in_sg = nx_build_sg_list(in_sg, (u8 *) data,
 145                                          &data_len, max_sg_len);
 146
 147                 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 148
 149                 to_process = data_len + buf_len;
 150                 leftover = total - to_process;
 151
 152                 /*
 153                  * we've hit the nx chip previously and we're updating
 154                  * again, so copy over the partial digest.
 155                  */
 156                 memcpy(csbcpb->cpb.sha256.input_partial_digest,
 157                                csbcpb->cpb.sha256.message_digest,
 158                                SHA256_DIGEST_SIZE);
 159
 160                 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
 161                         rc = -EINVAL;
 162                         goto out;
 163                 }
 164
 165                 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 166                                    desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 167                 if (rc)
 168                         goto out;
 169
 170                 atomic_inc(&(nx_ctx->stats->sha256_ops));
 171
 172                 total -= to_process;
 173                 data += to_process - buf_len;
 174                 buf_len = 0;
 175
 176         } while (leftover >= SHA256_BLOCK_SIZE);
 177
 178         /* copy the leftover back into the state struct */
 179         if (leftover)
 180                 memcpy(sctx->buf, data, leftover);
 181
 182         sctx->count += len;
 183         memcpy(sctx->state, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 184 out:
 185         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 186         return rc;
 187 }
 188
 189 static int nx_sha256_final(struct shash_desc *desc, u8 *out)
 190 {
 191         struct sha256_state *sctx = shash_desc_ctx(desc);
 192         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 193         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
 194         struct nx_sg *in_sg, *out_sg;
 195         unsigned long irq_flags;
 196         u32 max_sg_len;
 197         int rc = 0;
 198         int len;
 199
 200         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
 201
 202         max_sg_len = min_t(u64, nx_ctx->ap->sglen,
 203                         nx_driver.of.max_sg_len/sizeof(struct nx_sg));
 204         max_sg_len = min_t(u64, max_sg_len,
 205                         nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 206
 207         /* final is represented by continuing the operation and indicating that
 208          * this is not an intermediate operation */
 209         if (sctx->count >= SHA256_BLOCK_SIZE) {
 210                 /* we've hit the nx chip previously, now we're finalizing,
 211                  * so copy over the partial digest */
 212                 memcpy(csbcpb->cpb.sha256.input_partial_digest, sctx->state, SHA256_DIGEST_SIZE);
 213                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
 214                 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 215         } else {
 216                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
 217                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
 218         }
 219
 220         csbcpb->cpb.sha256.message_bit_length = (u64) (sctx->count * 8);
 221
 222         len = sctx->count & (SHA256_BLOCK_SIZE - 1);
 223         in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) sctx->buf,
 224                                  &len, max_sg_len);
 225
 226         if (len != (sctx->count & (SHA256_BLOCK_SIZE - 1))) {
 227                 rc = -EINVAL;
 228                 goto out;
 229         }
 230
 231         len = SHA256_DIGEST_SIZE;
 232         out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len, max_sg_len);
 233
 234         if (len != SHA256_DIGEST_SIZE) {
 235                 rc = -EINVAL;
 236                 goto out;
 237         }
 238
 239         nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 240         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 241         if (!nx_ctx->op.outlen) {
 242                 rc = -EINVAL;
 243                 goto out;
 244         }
 245
 246         rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 247                            desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 248         if (rc)
 249                 goto out;
 250
 251         atomic_inc(&(nx_ctx->stats->sha256_ops));
 252
 253         atomic64_add(sctx->count, &(nx_ctx->stats->sha256_bytes));
 254         memcpy(out, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 255 out:
 256         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 257         return rc;
 258 }
 259
 260 static int nx_sha256_export(struct shash_desc *desc, void *out)
 261 {
 262         struct sha256_state *sctx = shash_desc_ctx(desc);
 263
 264         memcpy(out, sctx, sizeof(*sctx));
 265
 266         return 0;
 267 }
 268
 269 static int nx_sha256_import(struct shash_desc *desc, const void *in)
 270 {
 271         struct sha256_state *sctx = shash_desc_ctx(desc);
 272
 273         memcpy(sctx, in, sizeof(*sctx));
 274
 275         return 0;
 276 }
 277
 278 struct shash_alg nx_shash_sha256_alg = {
 279         .digestsize = SHA256_DIGEST_SIZE,
 280         .init       = nx_sha256_init,
 281         .update     = nx_sha256_update,
 282         .final      = nx_sha256_final,
 283         .export     = nx_sha256_export,
 284         .import     = nx_sha256_import,
 285         .descsize   = sizeof(struct sha256_state),
 286         .statesize  = sizeof(struct sha256_state),
 287         .base       = {
 288                 .cra_name        = "sha256",
 289                 .cra_driver_name = "sha256-nx",
 290                 .cra_priority    = 300,
 291                 .cra_blocksize   = SHA256_BLOCK_SIZE,
 292                 .cra_module      = THIS_MODULE,
 293                 .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 294                 .cra_init        = nx_crypto_ctx_sha256_init,
 295                 .cra_exit        = nx_crypto_ctx_exit,
 296         }
 297 };