crypto/hmac.c

   1 /*
   2  * QEMU Crypto hmac algorithms
   3  *
   4  * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or
   7  * (at your option) any later version.  See the COPYING file in the
   8  * top-level directory.
   9  *
  10  */
  11
  12 #include "qemu/osdep.h"
  13 #include "qapi/error.h"
  14 #include "crypto/hmac.h"
  15 #include "hmacpriv.h"
  16
  17 static const char hex[] = "0123456789abcdef";
  18
  19 int qcrypto_hmac_bytesv(QCryptoHmac *hmac,
  20                         const struct iovec *iov,
  21                         size_t niov,
  22                         uint8_t **result,
  23                         size_t *resultlen,
  24                         Error **errp)
  25 {
  26     QCryptoHmacDriver *drv = hmac->driver;
  27
  28     return drv->hmac_bytesv(hmac, iov, niov, result, resultlen, errp);
  29 }
  30
  31 int qcrypto_hmac_bytes(QCryptoHmac *hmac,
  32                        const char *buf,
  33                        size_t len,
  34                        uint8_t **result,
  35                        size_t *resultlen,
  36                        Error **errp)
  37 {
  38     struct iovec iov = {
  39             .iov_base = (char *)buf,
  40             .iov_len = len
  41     };
  42
  43     return qcrypto_hmac_bytesv(hmac, &iov, 1, result, resultlen, errp);
  44 }
  45
  46 int qcrypto_hmac_digestv(QCryptoHmac *hmac,
  47                          const struct iovec *iov,
  48                          size_t niov,
  49                          char **digest,
  50                          Error **errp)
  51 {
  52     uint8_t *result = NULL;
  53     size_t resultlen = 0;
  54     size_t i;
  55
  56     if (qcrypto_hmac_bytesv(hmac, iov, niov, &result, &resultlen, errp) < 0) {
  57         return -1;
  58     }
  59
  60     *digest = g_new0(char, (resultlen * 2) + 1);
  61
  62     for (i = 0 ; i < resultlen ; i++) {
  63         (*digest)[(i * 2)] = hex[(result[i] >> 4) & 0xf];
  64         (*digest)[(i * 2) + 1] = hex[result[i] & 0xf];
  65     }
  66
  67     (*digest)[resultlen * 2] = '\0';
  68
  69     g_free(result);
  70     return 0;
  71 }
  72
  73 int qcrypto_hmac_digest(QCryptoHmac *hmac,
  74                         const char *buf,
  75                         size_t len,
  76                         char **digest,
  77                         Error **errp)
  78 {
  79     struct iovec iov = {
  80             .iov_base = (char *)buf,
  81             .iov_len = len
  82     };
  83
  84     return qcrypto_hmac_digestv(hmac, &iov, 1, digest, errp);
  85 }
  86
  87 QCryptoHmac *qcrypto_hmac_new(QCryptoHashAlgorithm alg,
  88                               const uint8_t *key, size_t nkey,
  89                               Error **errp)
  90 {
  91     QCryptoHmac *hmac;
  92     void *ctx = NULL;
  93     QCryptoHmacDriver *drv = NULL;
  94
  95 #ifdef CONFIG_AF_ALG
  96     ctx = qcrypto_afalg_hmac_ctx_new(alg, key, nkey, NULL);
  97     if (ctx) {
  98         drv = &qcrypto_hmac_afalg_driver;
  99     }
 100 #endif
 101
 102     if (!ctx) {
 103         ctx = qcrypto_hmac_ctx_new(alg, key, nkey, errp);
 104         if (!ctx) {
 105             return NULL;
 106         }
 107
 108         drv = &qcrypto_hmac_lib_driver;
 109     }
 110
 111     hmac = g_new0(QCryptoHmac, 1);
 112     hmac->alg = alg;
 113     hmac->opaque = ctx;
 114     hmac->driver = (void *)drv;
 115
 116     return hmac;
 117 }
 118
 119 void qcrypto_hmac_free(QCryptoHmac *hmac)
 120 {
 121     QCryptoHmacDriver *drv;
 122
 123     if (hmac) {
 124         drv = hmac->driver;
 125         drv->hmac_free(hmac);
 126         g_free(hmac);
 127     }
 128 }