1 /* 2 * QEMU Crypto hash algorithms 3 * 4 * Copyright (c) 2015 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 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 "crypto/hash.h" 22 23 #ifdef CONFIG_GNUTLS_HASH 24 #include <gnutls/gnutls.h> 25 #include <gnutls/crypto.h> 26 27 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALG_LAST] = { 28 [QCRYPTO_HASH_ALG_MD5] = GNUTLS_DIG_MD5, 29 [QCRYPTO_HASH_ALG_SHA1] = GNUTLS_DIG_SHA1, 30 [QCRYPTO_HASH_ALG_SHA256] = GNUTLS_DIG_SHA256, 31 }; 32 33 static size_t qcrypto_hash_alg_size[QCRYPTO_HASH_ALG_LAST] = { 34 [QCRYPTO_HASH_ALG_MD5] = 16, 35 [QCRYPTO_HASH_ALG_SHA1] = 20, 36 [QCRYPTO_HASH_ALG_SHA256] = 32, 37 }; 38 39 gboolean qcrypto_hash_supports(QCryptoHashAlgorithm alg) 40 { 41 if (alg < G_N_ELEMENTS(qcrypto_hash_alg_map)) { 42 return true; 43 } 44 return false; 45 } 46 47 size_t qcrypto_hash_digest_len(QCryptoHashAlgorithm alg) 48 { 49 if (alg >= G_N_ELEMENTS(qcrypto_hash_alg_size)) { 50 return 0; 51 } 52 return qcrypto_hash_alg_size[alg]; 53 } 54 55 56 int qcrypto_hash_bytesv(QCryptoHashAlgorithm alg, 57 const struct iovec *iov, 58 size_t niov, 59 uint8_t **result, 60 size_t *resultlen, 61 Error **errp) 62 { 63 int i, ret; 64 gnutls_hash_hd_t dig; 65 66 if (alg >= G_N_ELEMENTS(qcrypto_hash_alg_map)) { 67 error_setg(errp, 68 "Unknown hash algorithm %d", 69 alg); 70 return -1; 71 } 72 73 ret = gnutls_hash_init(&dig, qcrypto_hash_alg_map[alg]); 74 75 if (ret < 0) { 76 error_setg(errp, 77 "Unable to initialize hash algorithm: %s", 78 gnutls_strerror(ret)); 79 return -1; 80 } 81 82 for (i = 0; i < niov; i++) { 83 ret = gnutls_hash(dig, iov[i].iov_base, iov[i].iov_len); 84 if (ret < 0) { 85 error_setg(errp, 86 "Unable process hash data: %s", 87 gnutls_strerror(ret)); 88 goto error; 89 } 90 } 91 92 ret = gnutls_hash_get_len(qcrypto_hash_alg_map[alg]); 93 if (ret <= 0) { 94 error_setg(errp, 95 "Unable to get hash length: %s", 96 gnutls_strerror(ret)); 97 goto error; 98 } 99 if (*resultlen == 0) { 100 *resultlen = ret; 101 *result = g_new0(uint8_t, *resultlen); 102 } else if (*resultlen != ret) { 103 error_setg(errp, 104 "Result buffer size %zu is smaller than hash %d", 105 *resultlen, ret); 106 goto error; 107 } 108 109 gnutls_hash_deinit(dig, *result); 110 return 0; 111 112 error: 113 gnutls_hash_deinit(dig, NULL); 114 return -1; 115 } 116 117 #else /* ! CONFIG_GNUTLS_HASH */ 118 119 gboolean qcrypto_hash_supports(QCryptoHashAlgorithm alg G_GNUC_UNUSED) 120 { 121 return false; 122 } 123 124 int qcrypto_hash_bytesv(QCryptoHashAlgorithm alg, 125 const struct iovec *iov G_GNUC_UNUSED, 126 size_t niov G_GNUC_UNUSED, 127 uint8_t **result G_GNUC_UNUSED, 128 size_t *resultlen G_GNUC_UNUSED, 129 Error **errp) 130 { 131 error_setg(errp, 132 "Hash algorithm %d not supported without GNUTLS", 133 alg); 134 return -1; 135 } 136 137 #endif /* ! CONFIG_GNUTLS_HASH */ 138 139 int qcrypto_hash_bytes(QCryptoHashAlgorithm alg, 140 const char *buf, 141 size_t len, 142 uint8_t **result, 143 size_t *resultlen, 144 Error **errp) 145 { 146 struct iovec iov = { .iov_base = (char *)buf, 147 .iov_len = len }; 148 return qcrypto_hash_bytesv(alg, &iov, 1, result, resultlen, errp); 149 } 150 151 static const char hex[] = "0123456789abcdef"; 152 153 int qcrypto_hash_digestv(QCryptoHashAlgorithm alg, 154 const struct iovec *iov, 155 size_t niov, 156 char **digest, 157 Error **errp) 158 { 159 uint8_t *result = NULL; 160 size_t resultlen = 0; 161 size_t i; 162 163 if (qcrypto_hash_bytesv(alg, iov, niov, &result, &resultlen, errp) < 0) { 164 return -1; 165 } 166 167 *digest = g_new0(char, (resultlen * 2) + 1); 168 for (i = 0 ; i < resultlen ; i++) { 169 (*digest)[(i * 2)] = hex[(result[i] >> 4) & 0xf]; 170 (*digest)[(i * 2) + 1] = hex[result[i] & 0xf]; 171 } 172 (*digest)[resultlen * 2] = '\0'; 173 g_free(result); 174 return 0; 175 } 176 177 int qcrypto_hash_digest(QCryptoHashAlgorithm alg, 178 const char *buf, 179 size_t len, 180 char **digest, 181 Error **errp) 182 { 183 struct iovec iov = { .iov_base = (char *)buf, .iov_len = len }; 184 185 return qcrypto_hash_digestv(alg, &iov, 1, digest, errp); 186 } 187 188 int qcrypto_hash_base64v(QCryptoHashAlgorithm alg, 189 const struct iovec *iov, 190 size_t niov, 191 char **base64, 192 Error **errp) 193 { 194 uint8_t *result = NULL; 195 size_t resultlen = 0; 196 197 if (qcrypto_hash_bytesv(alg, iov, niov, &result, &resultlen, errp) < 0) { 198 return -1; 199 } 200 201 *base64 = g_base64_encode(result, resultlen); 202 g_free(result); 203 return 0; 204 } 205 206 int qcrypto_hash_base64(QCryptoHashAlgorithm alg, 207 const char *buf, 208 size_t len, 209 char **base64, 210 Error **errp) 211 { 212 struct iovec iov = { .iov_base = (char *)buf, .iov_len = len }; 213 214 return qcrypto_hash_base64v(alg, &iov, 1, base64, errp); 215 } 216