drivers/crypto/nx/nx-sha256.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /**
   3  * SHA-256 routines supporting the Power 7+ Nest Accelerators driver
   4  *
   5  * Copyright (C) 2011-2012 International Business Machines Inc.
   6  *
   7  * Author: Kent Yoder <yoder1@us.ibm.com>
   8  */
   9
  10 #include <crypto/internal/hash.h>
  11 #include <crypto/sha2.h>
  12 #include <linux/module.h>
  13 #include <asm/vio.h>
  14 #include <asm/byteorder.h>
  15
  16 #include "nx_csbcpb.h"
  17 #include "nx.h"
  18
  19
  20 static int nx_crypto_ctx_sha256_init(struct crypto_tfm *tfm)
  21 {
  22         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
  23         int err;
  24
  25         err = nx_crypto_ctx_sha_init(tfm);
  26         if (err)
  27                 return err;
  28
  29         nx_ctx_init(nx_ctx, HCOP_FC_SHA);
  30
  31         nx_ctx->ap = &nx_ctx->props[NX_PROPS_SHA256];
  32
  33         NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
  34
  35         return 0;
  36 }
  37
  38 static int nx_sha256_init(struct shash_desc *desc) {
  39         struct sha256_state *sctx = shash_desc_ctx(desc);
  40
  41         memset(sctx, 0, sizeof *sctx);
  42
  43         sctx->state[0] = __cpu_to_be32(SHA256_H0);
  44         sctx->state[1] = __cpu_to_be32(SHA256_H1);
  45         sctx->state[2] = __cpu_to_be32(SHA256_H2);
  46         sctx->state[3] = __cpu_to_be32(SHA256_H3);
  47         sctx->state[4] = __cpu_to_be32(SHA256_H4);
  48         sctx->state[5] = __cpu_to_be32(SHA256_H5);
  49         sctx->state[6] = __cpu_to_be32(SHA256_H6);
  50         sctx->state[7] = __cpu_to_be32(SHA256_H7);
  51         sctx->count = 0;
  52
  53         return 0;
  54 }
  55
  56 static int nx_sha256_update(struct shash_desc *desc, const u8 *data,
  57                             unsigned int len)
  58 {
  59         struct sha256_state *sctx = shash_desc_ctx(desc);
  60         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
  61         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
  62         struct nx_sg *out_sg;
  63         u64 to_process = 0, leftover, total;
  64         unsigned long irq_flags;
  65         int rc = 0;
  66         int data_len;
  67         u32 max_sg_len;
  68         u64 buf_len = (sctx->count % SHA256_BLOCK_SIZE);
  69
  70         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  71
  72         /* 2 cases for total data len:
  73          *  1: < SHA256_BLOCK_SIZE: copy into state, return 0
  74          *  2: >= SHA256_BLOCK_SIZE: process X blocks, copy in leftover
  75          */
  76         total = (sctx->count % SHA256_BLOCK_SIZE) + len;
  77         if (total < SHA256_BLOCK_SIZE) {
  78                 memcpy(sctx->buf + buf_len, data, len);
  79                 sctx->count += len;
  80                 goto out;
  81         }
  82
  83         memcpy(csbcpb->cpb.sha256.message_digest, sctx->state, SHA256_DIGEST_SIZE);
  84         NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
  85         NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
  86
  87         max_sg_len = min_t(u64, nx_ctx->ap->sglen,
  88                         nx_driver.of.max_sg_len/sizeof(struct nx_sg));
  89         max_sg_len = min_t(u64, max_sg_len,
  90                         nx_ctx->ap->databytelen/NX_PAGE_SIZE);
  91
  92         data_len = SHA256_DIGEST_SIZE;
  93         out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
  94                                   &data_len, max_sg_len);
  95         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
  96
  97         if (data_len != SHA256_DIGEST_SIZE) {
  98                 rc = -EINVAL;
  99                 goto out;
 100         }
 101
 102         do {
 103                 int used_sgs = 0;
 104                 struct nx_sg *in_sg = nx_ctx->in_sg;
 105
 106                 if (buf_len) {
 107                         data_len = buf_len;
 108                         in_sg = nx_build_sg_list(in_sg,
 109                                                  (u8 *) sctx->buf,
 110                                                  &data_len,
 111                                                  max_sg_len);
 112
 113                         if (data_len != buf_len) {
 114                                 rc = -EINVAL;
 115                                 goto out;
 116                         }
 117                         used_sgs = in_sg - nx_ctx->in_sg;
 118                 }
 119
 120                 /* to_process: SHA256_BLOCK_SIZE aligned chunk to be
 121                  * processed in this iteration. This value is restricted
 122                  * by sg list limits and number of sgs we already used
 123                  * for leftover data. (see above)
 124                  * In ideal case, we could allow NX_PAGE_SIZE * max_sg_len,
 125                  * but because data may not be aligned, we need to account
 126                  * for that too. */
 127                 to_process = min_t(u64, total,
 128                         (max_sg_len - 1 - used_sgs) * NX_PAGE_SIZE);
 129                 to_process = to_process & ~(SHA256_BLOCK_SIZE - 1);
 130
 131                 data_len = to_process - buf_len;
 132                 in_sg = nx_build_sg_list(in_sg, (u8 *) data,
 133                                          &data_len, max_sg_len);
 134
 135                 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 136
 137                 to_process = data_len + buf_len;
 138                 leftover = total - to_process;
 139
 140                 /*
 141                  * we've hit the nx chip previously and we're updating
 142                  * again, so copy over the partial digest.
 143                  */
 144                 memcpy(csbcpb->cpb.sha256.input_partial_digest,
 145                                csbcpb->cpb.sha256.message_digest,
 146                                SHA256_DIGEST_SIZE);
 147
 148                 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
 149                         rc = -EINVAL;
 150                         goto out;
 151                 }
 152
 153                 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 0);
 154                 if (rc)
 155                         goto out;
 156
 157                 atomic_inc(&(nx_ctx->stats->sha256_ops));
 158
 159                 total -= to_process;
 160                 data += to_process - buf_len;
 161                 buf_len = 0;
 162
 163         } while (leftover >= SHA256_BLOCK_SIZE);
 164
 165         /* copy the leftover back into the state struct */
 166         if (leftover)
 167                 memcpy(sctx->buf, data, leftover);
 168
 169         sctx->count += len;
 170         memcpy(sctx->state, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 171 out:
 172         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 173         return rc;
 174 }
 175
 176 static int nx_sha256_final(struct shash_desc *desc, u8 *out)
 177 {
 178         struct sha256_state *sctx = shash_desc_ctx(desc);
 179         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 180         struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
 181         struct nx_sg *in_sg, *out_sg;
 182         unsigned long irq_flags;
 183         u32 max_sg_len;
 184         int rc = 0;
 185         int len;
 186
 187         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
 188
 189         max_sg_len = min_t(u64, nx_ctx->ap->sglen,
 190                         nx_driver.of.max_sg_len/sizeof(struct nx_sg));
 191         max_sg_len = min_t(u64, max_sg_len,
 192                         nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 193
 194         /* final is represented by continuing the operation and indicating that
 195          * this is not an intermediate operation */
 196         if (sctx->count >= SHA256_BLOCK_SIZE) {
 197                 /* we've hit the nx chip previously, now we're finalizing,
 198                  * so copy over the partial digest */
 199                 memcpy(csbcpb->cpb.sha256.input_partial_digest, sctx->state, SHA256_DIGEST_SIZE);
 200                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
 201                 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 202         } else {
 203                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
 204                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
 205         }
 206
 207         csbcpb->cpb.sha256.message_bit_length = (u64) (sctx->count * 8);
 208
 209         len = sctx->count & (SHA256_BLOCK_SIZE - 1);
 210         in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) sctx->buf,
 211                                  &len, max_sg_len);
 212
 213         if (len != (sctx->count & (SHA256_BLOCK_SIZE - 1))) {
 214                 rc = -EINVAL;
 215                 goto out;
 216         }
 217
 218         len = SHA256_DIGEST_SIZE;
 219         out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len, max_sg_len);
 220
 221         if (len != SHA256_DIGEST_SIZE) {
 222                 rc = -EINVAL;
 223                 goto out;
 224         }
 225
 226         nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 227         nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 228         if (!nx_ctx->op.outlen) {
 229                 rc = -EINVAL;
 230                 goto out;
 231         }
 232
 233         rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 0);
 234         if (rc)
 235                 goto out;
 236
 237         atomic_inc(&(nx_ctx->stats->sha256_ops));
 238
 239         atomic64_add(sctx->count, &(nx_ctx->stats->sha256_bytes));
 240         memcpy(out, csbcpb->cpb.sha256.message_digest, SHA256_DIGEST_SIZE);
 241 out:
 242         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 243         return rc;
 244 }
 245
 246 static int nx_sha256_export(struct shash_desc *desc, void *out)
 247 {
 248         struct sha256_state *sctx = shash_desc_ctx(desc);
 249
 250         memcpy(out, sctx, sizeof(*sctx));
 251
 252         return 0;
 253 }
 254
 255 static int nx_sha256_import(struct shash_desc *desc, const void *in)
 256 {
 257         struct sha256_state *sctx = shash_desc_ctx(desc);
 258
 259         memcpy(sctx, in, sizeof(*sctx));
 260
 261         return 0;
 262 }
 263
 264 struct shash_alg nx_shash_sha256_alg = {
 265         .digestsize = SHA256_DIGEST_SIZE,
 266         .init       = nx_sha256_init,
 267         .update     = nx_sha256_update,
 268         .final      = nx_sha256_final,
 269         .export     = nx_sha256_export,
 270         .import     = nx_sha256_import,
 271         .descsize   = sizeof(struct sha256_state),
 272         .statesize  = sizeof(struct sha256_state),
 273         .base       = {
 274                 .cra_name        = "sha256",
 275                 .cra_driver_name = "sha256-nx",
 276                 .cra_priority    = 300,
 277                 .cra_blocksize   = SHA256_BLOCK_SIZE,
 278                 .cra_module      = THIS_MODULE,
 279                 .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 280                 .cra_init        = nx_crypto_ctx_sha256_init,
 281                 .cra_exit        = nx_crypto_ctx_exit,
 282         }
 283 };