 678307b605
			
		
	
	
		678307b605
		
	
	
	
	
		
			
			This adds support for using gnutls as a provider of the crypto hmac APIs. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
		
			
				
	
	
		
			140 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			140 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * QEMU Crypto hmac algorithms
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|  *
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|  * Copyright (c) 2021 Red Hat, Inc.
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|  *
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|  * Derived from hmac-gcrypt.c:
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|  *
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|  *   Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2 or
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|  * (at your option) any later version.  See the COPYING file in the
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|  * top-level directory.
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|  *
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include <gnutls/crypto.h>
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| 
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| #include "qapi/error.h"
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| #include "crypto/hmac.h"
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| #include "hmacpriv.h"
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| 
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| static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
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|     [QCRYPTO_HASH_ALG_MD5] = GNUTLS_MAC_MD5,
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|     [QCRYPTO_HASH_ALG_SHA1] = GNUTLS_MAC_SHA1,
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|     [QCRYPTO_HASH_ALG_SHA224] = GNUTLS_MAC_SHA224,
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|     [QCRYPTO_HASH_ALG_SHA256] = GNUTLS_MAC_SHA256,
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|     [QCRYPTO_HASH_ALG_SHA384] = GNUTLS_MAC_SHA384,
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|     [QCRYPTO_HASH_ALG_SHA512] = GNUTLS_MAC_SHA512,
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|     [QCRYPTO_HASH_ALG_RIPEMD160] = GNUTLS_MAC_RMD160,
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| };
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| 
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| typedef struct QCryptoHmacGnutls QCryptoHmacGnutls;
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| struct QCryptoHmacGnutls {
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|     gnutls_hmac_hd_t handle;
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| };
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| 
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| bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
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| {
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|     size_t i;
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|     const gnutls_digest_algorithm_t *algs;
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|     if (alg >= G_N_ELEMENTS(qcrypto_hmac_alg_map) ||
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|         qcrypto_hmac_alg_map[alg] == GNUTLS_DIG_UNKNOWN) {
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|         return false;
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|     }
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|     algs = gnutls_digest_list();
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|     for (i = 0; algs[i] != GNUTLS_DIG_UNKNOWN; i++) {
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|         if (algs[i] == qcrypto_hmac_alg_map[alg]) {
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|             return true;
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|         }
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|     }
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|     return false;
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| }
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| 
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| void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
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|                            const uint8_t *key, size_t nkey,
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|                            Error **errp)
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| {
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|     QCryptoHmacGnutls *ctx;
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|     int err;
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| 
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|     if (!qcrypto_hmac_supports(alg)) {
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|         error_setg(errp, "Unsupported hmac algorithm %s",
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|                    QCryptoHashAlgorithm_str(alg));
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|         return NULL;
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|     }
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| 
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|     ctx = g_new0(QCryptoHmacGnutls, 1);
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| 
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|     err = gnutls_hmac_init(&ctx->handle,
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|                            qcrypto_hmac_alg_map[alg],
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|                            (const void *)key, nkey);
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|     if (err != 0) {
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|         error_setg(errp, "Cannot initialize hmac: %s",
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|                    gnutls_strerror(err));
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|         goto error;
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|     }
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| 
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|     return ctx;
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| 
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| error:
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|     g_free(ctx);
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|     return NULL;
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| }
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| 
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| static void
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| qcrypto_gnutls_hmac_ctx_free(QCryptoHmac *hmac)
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| {
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|     QCryptoHmacGnutls *ctx;
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| 
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|     ctx = hmac->opaque;
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|     gnutls_hmac_deinit(ctx->handle, NULL);
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| 
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|     g_free(ctx);
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| }
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| 
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| static int
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| qcrypto_gnutls_hmac_bytesv(QCryptoHmac *hmac,
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|                            const struct iovec *iov,
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|                            size_t niov,
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|                            uint8_t **result,
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|                            size_t *resultlen,
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|                            Error **errp)
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| {
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|     QCryptoHmacGnutls *ctx;
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|     uint32_t ret;
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|     int i;
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| 
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|     ctx = hmac->opaque;
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| 
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|     for (i = 0; i < niov; i++) {
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|         gnutls_hmac(ctx->handle, iov[i].iov_base, iov[i].iov_len);
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|     }
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| 
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|     ret = gnutls_hmac_get_len(qcrypto_hmac_alg_map[hmac->alg]);
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|     if (ret <= 0) {
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|         error_setg(errp, "Unable to get hmac length: %s",
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|                    gnutls_strerror(ret));
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|         return -1;
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|     }
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| 
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|     if (*resultlen == 0) {
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|         *resultlen = ret;
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|         *result = g_new0(uint8_t, *resultlen);
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|     } else if (*resultlen != ret) {
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|         error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
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|                    *resultlen, ret);
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|         return -1;
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|     }
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| 
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|     gnutls_hmac_output(ctx->handle, *result);
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| 
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|     return 0;
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| }
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| 
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| QCryptoHmacDriver qcrypto_hmac_lib_driver = {
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|     .hmac_bytesv = qcrypto_gnutls_hmac_bytesv,
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|     .hmac_free = qcrypto_gnutls_hmac_ctx_free,
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| };
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