crypto/hash-gnutls.c

   1 /*
   2  * QEMU Crypto hash algorithms
   3  *
   4  * Copyright (c) 2021 Red Hat, Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #include "qemu/osdep.h"
  22 #include <gnutls/crypto.h>
  23 #include "qapi/error.h"
  24 #include "crypto/hash.h"
  25 #include "hashpriv.h"
  26
  27
  28 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALG__MAX] = {
  29     [QCRYPTO_HASH_ALG_MD5] = GNUTLS_DIG_MD5,
  30     [QCRYPTO_HASH_ALG_SHA1] = GNUTLS_DIG_SHA1,
  31     [QCRYPTO_HASH_ALG_SHA224] = GNUTLS_DIG_SHA224,
  32     [QCRYPTO_HASH_ALG_SHA256] = GNUTLS_DIG_SHA256,
  33     [QCRYPTO_HASH_ALG_SHA384] = GNUTLS_DIG_SHA384,
  34     [QCRYPTO_HASH_ALG_SHA512] = GNUTLS_DIG_SHA512,
  35     [QCRYPTO_HASH_ALG_RIPEMD160] = GNUTLS_DIG_RMD160,
  36 };
  37
  38 gboolean qcrypto_hash_supports(QCryptoHashAlgorithm alg)
  39 {
  40     size_t i;
  41     const gnutls_digest_algorithm_t *algs;
  42     if (alg >= G_N_ELEMENTS(qcrypto_hash_alg_map) ||
  43         qcrypto_hash_alg_map[alg] == GNUTLS_DIG_UNKNOWN) {
  44         return false;
  45     }
  46     algs = gnutls_digest_list();
  47     for (i = 0; algs[i] != GNUTLS_DIG_UNKNOWN; i++) {
  48         if (algs[i] == qcrypto_hash_alg_map[alg]) {
  49             return true;
  50         }
  51     }
  52     return false;
  53 }
  54
  55
  56 static int
  57 qcrypto_gnutls_hash_bytesv(QCryptoHashAlgorithm alg,
  58                            const struct iovec *iov,
  59                            size_t niov,
  60                            uint8_t **result,
  61                            size_t *resultlen,
  62                            Error **errp)
  63 {
  64     int i, ret;
  65     gnutls_hash_hd_t hash;
  66
  67     if (!qcrypto_hash_supports(alg)) {
  68         error_setg(errp,
  69                    "Unknown hash algorithm %d",
  70                    alg);
  71         return -1;
  72     }
  73
  74     ret = gnutls_hash_get_len(qcrypto_hash_alg_map[alg]);
  75     if (*resultlen == 0) {
  76         *resultlen = ret;
  77         *result = g_new0(uint8_t, *resultlen);
  78     } else if (*resultlen != ret) {
  79         error_setg(errp,
  80                    "Result buffer size %zu is smaller than hash %d",
  81                    *resultlen, ret);
  82         return -1;
  83     }
  84
  85     ret = gnutls_hash_init(&hash, qcrypto_hash_alg_map[alg]);
  86     if (ret < 0) {
  87         error_setg(errp,
  88                    "Unable to initialize hash algorithm: %s",
  89                    gnutls_strerror(ret));
  90         return -1;
  91     }
  92
  93     for (i = 0; i < niov; i++) {
  94         gnutls_hash(hash, iov[i].iov_base, iov[i].iov_len);
  95     }
  96
  97     gnutls_hash_deinit(hash, *result);
  98     return 0;
  99 }
 100
 101
 102 QCryptoHashDriver qcrypto_hash_lib_driver = {
 103     .hash_bytesv = qcrypto_gnutls_hash_bytesv,
 104 };