1 /* 2 * QEMU Crypto block IV generator - plain 3 * 4 * Copyright (c) 2015-2016 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 "qapi/error.h" 23 #include "qemu/bswap.h" 24 #include "crypto/ivgen-plain.h" 25 26 static int qcrypto_ivgen_plain_init(QCryptoIVGen *ivgen, 27 const uint8_t *key, size_t nkey, 28 Error **errp) 29 { 30 return 0; 31 } 32 33 static int qcrypto_ivgen_plain_calculate(QCryptoIVGen *ivgen, 34 uint64_t sector, 35 uint8_t *iv, size_t niv, 36 Error **errp) 37 { 38 size_t ivprefix; 39 uint32_t shortsector = cpu_to_le32((sector & 0xffffffff)); 40 ivprefix = sizeof(shortsector); 41 if (ivprefix > niv) { 42 ivprefix = niv; 43 } 44 memcpy(iv, &shortsector, ivprefix); 45 if (ivprefix < niv) { 46 memset(iv + ivprefix, 0, niv - ivprefix); 47 } 48 return 0; 49 } 50 51 static void qcrypto_ivgen_plain_cleanup(QCryptoIVGen *ivgen) 52 { 53 } 54 55 56 struct QCryptoIVGenDriver qcrypto_ivgen_plain = { 57 .init = qcrypto_ivgen_plain_init, 58 .calculate = qcrypto_ivgen_plain_calculate, 59 .cleanup = qcrypto_ivgen_plain_cleanup, 60 }; 61 62