1 /* 2 * QEMU Crypto hmac algorithms (based on glib) 3 * 4 * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. 5 * 6 * Authors: 7 * Longpeng(Mike) <longpeng2@huawei.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or 10 * (at your option) any later version. See the COPYING file in the 11 * top-level directory. 12 * 13 */ 14 15 #include "qemu/osdep.h" 16 #include "qapi/error.h" 17 #include "crypto/hmac.h" 18 #include "hmacpriv.h" 19 20 static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = { 21 [QCRYPTO_HASH_ALG_MD5] = G_CHECKSUM_MD5, 22 [QCRYPTO_HASH_ALG_SHA1] = G_CHECKSUM_SHA1, 23 [QCRYPTO_HASH_ALG_SHA256] = G_CHECKSUM_SHA256, 24 /* Support for HMAC SHA-512 in GLib 2.42 */ 25 #if GLIB_CHECK_VERSION(2, 42, 0) 26 [QCRYPTO_HASH_ALG_SHA512] = G_CHECKSUM_SHA512, 27 #else 28 [QCRYPTO_HASH_ALG_SHA512] = -1, 29 #endif 30 [QCRYPTO_HASH_ALG_SHA224] = -1, 31 [QCRYPTO_HASH_ALG_SHA384] = -1, 32 [QCRYPTO_HASH_ALG_RIPEMD160] = -1, 33 }; 34 35 typedef struct QCryptoHmacGlib QCryptoHmacGlib; 36 struct QCryptoHmacGlib { 37 GHmac *ghmac; 38 }; 39 40 bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg) 41 { 42 if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) && 43 qcrypto_hmac_alg_map[alg] != -1) { 44 return true; 45 } 46 47 return false; 48 } 49 50 void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg, 51 const uint8_t *key, size_t nkey, 52 Error **errp) 53 { 54 QCryptoHmacGlib *ctx; 55 56 if (!qcrypto_hmac_supports(alg)) { 57 error_setg(errp, "Unsupported hmac algorithm %s", 58 QCryptoHashAlgorithm_str(alg)); 59 return NULL; 60 } 61 62 ctx = g_new0(QCryptoHmacGlib, 1); 63 64 ctx->ghmac = g_hmac_new(qcrypto_hmac_alg_map[alg], 65 (const uint8_t *)key, nkey); 66 if (!ctx->ghmac) { 67 error_setg(errp, "Cannot initialize hmac and set key"); 68 goto error; 69 } 70 71 return ctx; 72 73 error: 74 g_free(ctx); 75 return NULL; 76 } 77 78 static void 79 qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac) 80 { 81 QCryptoHmacGlib *ctx; 82 83 ctx = hmac->opaque; 84 g_hmac_unref(ctx->ghmac); 85 86 g_free(ctx); 87 } 88 89 static int 90 qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac, 91 const struct iovec *iov, 92 size_t niov, 93 uint8_t **result, 94 size_t *resultlen, 95 Error **errp) 96 { 97 QCryptoHmacGlib *ctx; 98 int i, ret; 99 100 ctx = hmac->opaque; 101 102 for (i = 0; i < niov; i++) { 103 g_hmac_update(ctx->ghmac, iov[i].iov_base, iov[i].iov_len); 104 } 105 106 ret = g_checksum_type_get_length(qcrypto_hmac_alg_map[hmac->alg]); 107 if (ret < 0) { 108 error_setg(errp, "Unable to get hmac length"); 109 return -1; 110 } 111 112 if (*resultlen == 0) { 113 *resultlen = ret; 114 *result = g_new0(uint8_t, *resultlen); 115 } else if (*resultlen != ret) { 116 error_setg(errp, "Result buffer size %zu is smaller than hmac %d", 117 *resultlen, ret); 118 return -1; 119 } 120 121 g_hmac_get_digest(ctx->ghmac, *result, resultlen); 122 123 return 0; 124 } 125 126 QCryptoHmacDriver qcrypto_hmac_lib_driver = { 127 .hmac_bytesv = qcrypto_glib_hmac_bytesv, 128 .hmac_free = qcrypto_glib_hmac_ctx_free, 129 }; 130