1 /* 2 * QEMU Crypto PBKDF support (Password-Based Key Derivation Function) 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/pbkdf.h" 25 26 bool qcrypto_pbkdf2_supports(QCryptoHashAlgorithm hash) 27 { 28 switch (hash) { 29 case QCRYPTO_HASH_ALG_MD5: 30 case QCRYPTO_HASH_ALG_SHA1: 31 case QCRYPTO_HASH_ALG_SHA224: 32 case QCRYPTO_HASH_ALG_SHA256: 33 case QCRYPTO_HASH_ALG_SHA384: 34 case QCRYPTO_HASH_ALG_SHA512: 35 case QCRYPTO_HASH_ALG_RIPEMD160: 36 return true; 37 default: 38 return false; 39 } 40 } 41 42 int qcrypto_pbkdf2(QCryptoHashAlgorithm hash, 43 const uint8_t *key, size_t nkey, 44 const uint8_t *salt, size_t nsalt, 45 uint64_t iterations, 46 uint8_t *out, size_t nout, 47 Error **errp) 48 { 49 static const int hash_map[QCRYPTO_HASH_ALG__MAX] = { 50 [QCRYPTO_HASH_ALG_MD5] = GNUTLS_DIG_MD5, 51 [QCRYPTO_HASH_ALG_SHA1] = GNUTLS_DIG_SHA1, 52 [QCRYPTO_HASH_ALG_SHA224] = GNUTLS_DIG_SHA224, 53 [QCRYPTO_HASH_ALG_SHA256] = GNUTLS_DIG_SHA256, 54 [QCRYPTO_HASH_ALG_SHA384] = GNUTLS_DIG_SHA384, 55 [QCRYPTO_HASH_ALG_SHA512] = GNUTLS_DIG_SHA512, 56 [QCRYPTO_HASH_ALG_RIPEMD160] = GNUTLS_DIG_RMD160, 57 }; 58 int ret; 59 const gnutls_datum_t gkey = { (unsigned char *)key, nkey }; 60 const gnutls_datum_t gsalt = { (unsigned char *)salt, nsalt }; 61 62 if (iterations > ULONG_MAX) { 63 error_setg_errno(errp, ERANGE, 64 "PBKDF iterations %llu must be less than %lu", 65 (long long unsigned)iterations, ULONG_MAX); 66 return -1; 67 } 68 69 if (hash >= G_N_ELEMENTS(hash_map) || 70 hash_map[hash] == GNUTLS_DIG_UNKNOWN) { 71 error_setg_errno(errp, ENOSYS, 72 "PBKDF does not support hash algorithm %s", 73 QCryptoHashAlgorithm_str(hash)); 74 return -1; 75 } 76 77 ret = gnutls_pbkdf2(hash_map[hash], 78 &gkey, 79 &gsalt, 80 iterations, 81 out, 82 nout); 83 if (ret != 0) { 84 error_setg(errp, "Cannot derive password: %s", 85 gnutls_strerror(ret)); 86 return -1; 87 } 88 89 return 0; 90 } 91