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
  27 #include "nx_csbcpb.h"
  28 #include "nx.h"
  29
  30
  31 static int nx_sha256_init(struct shash_desc *desc)
  32 {
  33         struct sha256_state *sctx = shash_desc_ctx(desc);
  34         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
  35         struct nx_sg *out_sg;
  36
  37         nx_ctx_init(nx_ctx, HCOP_FC_SHA);
  38
  39         memset(sctx, 0, sizeof *sctx);
  40
  41         nx_ctx->ap = &nx_ctx->props[NX_PROPS_SHA256];
  42
  43         NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
  44         out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
  45                                   SHA256_DIGEST_SIZE, nx_ctx->ap->sglen);
  46         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
  47
  48         return 0;
  49 }
  50
  51 static int nx_sha256_update(struct shash_desc *desc, const u8 *data,
  52                             unsigned int len)
  53 {
  54         struct sha256_state *sctx = shash_desc_ctx(desc);
  55         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
  56         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
  57         struct nx_sg *in_sg;
  58         u64 to_process, leftover;
  59         int rc = 0;
  60
  61         if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) {
  62                 /* we've hit the nx chip previously and we're updating again,
  63                  * so copy over the partial digest */
  64                 memcpy(csbcpb->cpb.sha256.input_partial_digest,
  65                        csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
  66         }
  67
  68         /* 2 cases for total data len:
  69          *  1: <= SHA256_BLOCK_SIZE: copy into state, return 0
  70          *  2: > SHA256_BLOCK_SIZE: process X blocks, copy in leftover
  71          */
  72         if (len + sctx->count <= SHA256_BLOCK_SIZE) {
  73                 memcpy(sctx->buf + sctx->count, data, len);
  74                 sctx->count += len;
  75                 goto out;
  76         }
  77
  78         /* to_process: the SHA256_BLOCK_SIZE data chunk to process in this
  79          * update */
  80         to_process = (sctx->count + len) & ~(SHA256_BLOCK_SIZE - 1);
  81         leftover = (sctx->count + len) & (SHA256_BLOCK_SIZE - 1);
  82
  83         if (sctx->count) {
  84                 in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buf,
  85                                          sctx->count, nx_ctx->ap->sglen);
  86                 in_sg = nx_build_sg_list(in_sg, (u8 *)data,
  87                                          to_process - sctx->count,
  88                                          nx_ctx->ap->sglen);
  89                 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) *
  90                                         sizeof(struct nx_sg);
  91         } else {
  92                 in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)data,
  93                                          to_process, nx_ctx->ap->sglen);
  94                 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) *
  95                                         sizeof(struct nx_sg);
  96         }
  97
  98         NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
  99
 100         if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
 101                 rc = -EINVAL;
 102                 goto out;
 103         }
 104
 105         rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 106                            desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 107         if (rc)
 108                 goto out;
 109
 110         atomic_inc(&(nx_ctx->stats->sha256_ops));
 111
 112         /* copy the leftover back into the state struct */
 113         memcpy(sctx->buf, data + len - leftover, leftover);
 114         sctx->count = leftover;
 115
 116         csbcpb->cpb.sha256.message_bit_length += (u64)
 117                 (csbcpb->cpb.sha256.spbc * 8);
 118
 119         /* everything after the first update is continuation */
 120         NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 121 out:
 122         return rc;
 123 }
 124
 125 static int nx_sha256_final(struct shash_desc *desc, u8 *out)
 126 {
 127         struct sha256_state *sctx = shash_desc_ctx(desc);
 128         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 129         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
 130         struct nx_sg *in_sg, *out_sg;
 131         int rc;
 132
 133         if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) {
 134                 /* we've hit the nx chip previously, now we're finalizing,
 135                  * so copy over the partial digest */
 136                 memcpy(csbcpb->cpb.sha256.input_partial_digest,
 137                        csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 138         }
 139
 140         /* final is represented by continuing the operation and indicating that
 141          * this is not an intermediate operation */
 142         NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
 143
 144         csbcpb->cpb.sha256.message_bit_length += (u64)(sctx->count * 8);
 145
 146         in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buf,
 147                                  sctx->count, nx_ctx->ap->sglen);
 148         out_sg = nx_build_sg_list(nx_ctx->out_sg, out, SHA256_DIGEST_SIZE,
 149                                   nx_ctx->ap->sglen);
 150         nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 151         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 152
 153         if (!nx_ctx->op.outlen) {
 154                 rc = -EINVAL;
 155                 goto out;
 156         }
 157
 158         rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 159                            desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 160         if (rc)
 161                 goto out;
 162
 163         atomic_inc(&(nx_ctx->stats->sha256_ops));
 164
 165         atomic64_add(csbcpb->cpb.sha256.message_bit_length,
 166                      &(nx_ctx->stats->sha256_bytes));
 167         memcpy(out, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 168 out:
 169         return rc;
 170 }
 171
 172 static int nx_sha256_export(struct shash_desc *desc, void *out)
 173 {
 174         struct sha256_state *sctx = shash_desc_ctx(desc);
 175         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 176         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
 177         struct sha256_state *octx = out;
 178
 179         octx->count = sctx->count +
 180                       (csbcpb->cpb.sha256.message_bit_length / 8);
 181         memcpy(octx->buf, sctx->buf, sizeof(octx->buf));
 182
 183         /* if no data has been processed yet, we need to export SHA256's
 184          * initial data, in case this context gets imported into a software
 185          * context */
 186         if (csbcpb->cpb.sha256.message_bit_length)
 187                 memcpy(octx->state, csbcpb->cpb.sha256.message_digest,
 188                        SHA256_DIGEST_SIZE);
 189         else {
 190                 octx->state[0] = SHA256_H0;
 191                 octx->state[1] = SHA256_H1;
 192                 octx->state[2] = SHA256_H2;
 193                 octx->state[3] = SHA256_H3;
 194                 octx->state[4] = SHA256_H4;
 195                 octx->state[5] = SHA256_H5;
 196                 octx->state[6] = SHA256_H6;
 197                 octx->state[7] = SHA256_H7;
 198         }
 199
 200         return 0;
 201 }
 202
 203 static int nx_sha256_import(struct shash_desc *desc, const void *in)
 204 {
 205         struct sha256_state *sctx = shash_desc_ctx(desc);
 206         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 207         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
 208         const struct sha256_state *ictx = in;
 209
 210         memcpy(sctx->buf, ictx->buf, sizeof(ictx->buf));
 211
 212         sctx->count = ictx->count & 0x3f;
 213         csbcpb->cpb.sha256.message_bit_length = (ictx->count & ~0x3f) * 8;
 214
 215         if (csbcpb->cpb.sha256.message_bit_length) {
 216                 memcpy(csbcpb->cpb.sha256.message_digest, ictx->state,
 217                        SHA256_DIGEST_SIZE);
 218
 219                 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 220                 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
 221         }
 222
 223         return 0;
 224 }
 225
 226 struct shash_alg nx_shash_sha256_alg = {
 227         .digestsize = SHA256_DIGEST_SIZE,
 228         .init       = nx_sha256_init,
 229         .update     = nx_sha256_update,
 230         .final      = nx_sha256_final,
 231         .export     = nx_sha256_export,
 232         .import     = nx_sha256_import,
 233         .descsize   = sizeof(struct sha256_state),
 234         .statesize  = sizeof(struct sha256_state),
 235         .base       = {
 236                 .cra_name        = "sha256",
 237                 .cra_driver_name = "sha256-nx",
 238                 .cra_priority    = 300,
 239                 .cra_flags       = CRYPTO_ALG_TYPE_SHASH,
 240                 .cra_blocksize   = SHA256_BLOCK_SIZE,
 241                 .cra_module      = THIS_MODULE,
 242                 .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 243                 .cra_init        = nx_crypto_ctx_sha_init,
 244                 .cra_exit        = nx_crypto_ctx_exit,
 245         }
 246 };