1 /* 2 * QEMU Crypto hash algorithms 3 * 4 * Copyright (c) 2016 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 "qemu/osdep.h" 22 #include <gcrypt.h> 23 #include "qapi/error.h" 24 #include "crypto/hash.h" 25 26 27 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALG__MAX] = { 28 [QCRYPTO_HASH_ALG_MD5] = GCRY_MD_MD5, 29 [QCRYPTO_HASH_ALG_SHA1] = GCRY_MD_SHA1, 30 [QCRYPTO_HASH_ALG_SHA224] = GCRY_MD_SHA224, 31 [QCRYPTO_HASH_ALG_SHA256] = GCRY_MD_SHA256, 32 [QCRYPTO_HASH_ALG_SHA384] = GCRY_MD_SHA384, 33 [QCRYPTO_HASH_ALG_SHA512] = GCRY_MD_SHA512, 34 [QCRYPTO_HASH_ALG_RIPEMD160] = GCRY_MD_RMD160, 35 }; 36 37 gboolean qcrypto_hash_supports(QCryptoHashAlgorithm alg) 38 { 39 if (alg < G_N_ELEMENTS(qcrypto_hash_alg_map) && 40 qcrypto_hash_alg_map[alg] != GCRY_MD_NONE) { 41 return true; 42 } 43 return false; 44 } 45 46 47 int qcrypto_hash_bytesv(QCryptoHashAlgorithm alg, 48 const struct iovec *iov, 49 size_t niov, 50 uint8_t **result, 51 size_t *resultlen, 52 Error **errp) 53 { 54 int i, ret; 55 gcry_md_hd_t md; 56 unsigned char *digest; 57 58 if (!qcrypto_hash_supports(alg)) { 59 error_setg(errp, 60 "Unknown hash algorithm %d", 61 alg); 62 return -1; 63 } 64 65 ret = gcry_md_open(&md, qcrypto_hash_alg_map[alg], 0); 66 67 if (ret < 0) { 68 error_setg(errp, 69 "Unable to initialize hash algorithm: %s", 70 gcry_strerror(ret)); 71 return -1; 72 } 73 74 for (i = 0; i < niov; i++) { 75 gcry_md_write(md, iov[i].iov_base, iov[i].iov_len); 76 } 77 78 ret = gcry_md_get_algo_dlen(qcrypto_hash_alg_map[alg]); 79 if (ret <= 0) { 80 error_setg(errp, 81 "Unable to get hash length: %s", 82 gcry_strerror(ret)); 83 goto error; 84 } 85 if (*resultlen == 0) { 86 *resultlen = ret; 87 *result = g_new0(uint8_t, *resultlen); 88 } else if (*resultlen != ret) { 89 error_setg(errp, 90 "Result buffer size %zu is smaller than hash %d", 91 *resultlen, ret); 92 goto error; 93 } 94 95 digest = gcry_md_read(md, 0); 96 if (!digest) { 97 error_setg(errp, 98 "No digest produced"); 99 goto error; 100 } 101 memcpy(*result, digest, *resultlen); 102 103 gcry_md_close(md); 104 return 0; 105 106 error: 107 gcry_md_close(md); 108 return -1; 109 } 110