int KSI_HmacHasher_reset(KSI_HmacHasher *hasher) {
int res = KSI_UNKNOWN_ERROR;
if (hasher == NULL) {
res = KSI_INVALID_ARGUMENT;
goto cleanup;
}
KSI_ERR_clearErrors(hasher->ctx);
res = KSI_DataHasher_reset(hasher->dataHasher);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
/* Hash inner data. */
KSI_LOG_logBlob(hasher->ctx, KSI_LOG_DEBUG, "Adding ipad", hasher->ipadXORkey, hasher->blockSize);
res = KSI_DataHasher_add(hasher->dataHasher, hasher->ipadXORkey, hasher->blockSize);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
res = KSI_OK;
cleanup:
return res;
}
int KSI_DataHasher_open(KSI_CTX *ctx, KSI_HashAlgorithm algo_id, KSI_DataHasher **hasher) {
int res = KSI_UNKNOWN_ERROR;
KSI_DataHasher *tmp_hasher = NULL;
CRYPTO_HASH_CTX *tmp_cryptoCTX = NULL;
HCRYPTPROV tmp_CSP = 0;
KSI_ERR_clearErrors(ctx);
if (ctx == NULL || hasher == NULL){
res = KSI_INVALID_ARGUMENT;
goto cleanup;
}
/*Test if hash algorithm is valid*/
if (!KSI_isHashAlgorithmSupported(algo_id)) {
KSI_pushError(ctx, res = KSI_UNAVAILABLE_HASH_ALGORITHM, NULL);
goto cleanup;
}
/*Create new abstract data hasher object*/
tmp_hasher = KSI_new(KSI_DataHasher);
if (tmp_hasher == NULL) {
KSI_pushError(ctx, res = KSI_OUT_OF_MEMORY, NULL);
goto cleanup;
}
tmp_hasher->hashContext = NULL;
tmp_hasher->ctx = ctx;
tmp_hasher->algorithm = algo_id;
tmp_hasher->closeExisting = closeExisting;
/*Create new helper context for crypto api*/
res = CRYPTO_HASH_CTX_new(&tmp_cryptoCTX);
if (res != KSI_OK) {
KSI_pushError(ctx, res, NULL);
goto cleanup;
}
/*Create new crypto service provider (CSP)*/
if (!CryptAcquireContext(&tmp_CSP, NULL, NULL, PROV_RSA_AES, CRYPT_VERIFYCONTEXT)){
char errm[1024];
KSI_snprintf(errm, sizeof(errm), "Wincrypt Error (%d)", GetLastError());
KSI_pushError(ctx, res = KSI_CRYPTO_FAILURE, errm);
goto cleanup;
}
/*Set CSP in helper struct*/
tmp_cryptoCTX->pt_CSP = tmp_CSP;
/*Set helper struct in abstract struct*/
tmp_hasher->hashContext = tmp_cryptoCTX;
res = KSI_DataHasher_reset(tmp_hasher);
if (res != KSI_OK) {
KSI_pushError(ctx, res, NULL);
goto cleanup;
}
*hasher = tmp_hasher;
tmp_hasher = NULL;
tmp_cryptoCTX = NULL;
tmp_CSP = 0;
res = KSI_OK;
cleanup:
KSI_DataHasher_free(tmp_hasher);
if (tmp_CSP) CryptReleaseContext(tmp_CSP, 0);
CRYPTO_HASH_CTX_free(tmp_cryptoCTX);
return res;
}
int KSI_HmacHasher_close(KSI_HmacHasher *hasher, KSI_DataHash **hmac) {
int res = KSI_UNKNOWN_ERROR;
KSI_DataHash *innerHash = NULL;
KSI_DataHash *outerHash = NULL;
const unsigned char *digest = NULL;
size_t digest_len = 0;
if (hasher == NULL || hmac == NULL) {
res = KSI_INVALID_ARGUMENT;
goto cleanup;
}
KSI_ERR_clearErrors(hasher->ctx);
KSI_LOG_debug(hasher->ctx, "Closing inner hasher");
res = KSI_DataHasher_close(hasher->dataHasher, &innerHash);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
/* Hash outer data. */
res = KSI_DataHasher_reset(hasher->dataHasher);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
KSI_LOG_logBlob(hasher->ctx, KSI_LOG_DEBUG, "Adding opad", hasher->opadXORkey, hasher->blockSize);
res = KSI_DataHasher_add(hasher->dataHasher, hasher->opadXORkey, hasher->blockSize);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
res = KSI_DataHash_extract(innerHash, NULL, &digest, &digest_len);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
KSI_LOG_logBlob(hasher->ctx, KSI_LOG_DEBUG, "Adding inner hash", digest, digest_len);
res = KSI_DataHasher_add(hasher->dataHasher, digest, digest_len);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
KSI_LOG_debug(hasher->ctx, "Closing outer hasher");
res = KSI_DataHasher_close(hasher->dataHasher, &outerHash);
if (res != KSI_OK) {
KSI_pushError(hasher->ctx, res, NULL);
goto cleanup;
}
*hmac = KSI_DataHash_ref(outerHash);
res = KSI_OK;
cleanup:
KSI_DataHash_free(innerHash);
KSI_DataHash_free(outerHash);
return res;
}
