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-rw-r--r--libparc/parc/security/parc_SymmetricKeySigner.c268
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diff --git a/libparc/parc/security/parc_SymmetricKeySigner.c b/libparc/parc/security/parc_SymmetricKeySigner.c
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+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/**
+ */
+#include <config.h>
+
+#include <parc/algol/parc_Object.h>
+#include <parc/algol/parc_DisplayIndented.h>
+#include <parc/algol/parc_Memory.h>
+
+#include <parc/security/parc_Signer.h>
+#include <parc/security/parc_SymmetricKeySigner.h>
+#include <parc/security/parc_KeyStore.h>
+
+#include <openssl/opensslv.h>
+#include <openssl/asn1.h>
+#include <openssl/asn1t.h>
+#include <openssl/safestack.h>
+#include <openssl/bn.h>
+#include <openssl/evp.h>
+#include <openssl/sha.h>
+#include <openssl/rand.h>
+#include <openssl/aes.h>
+#include <openssl/hmac.h>
+
+#define AES_KEYSTORE_VERSION 1L
+#define IV_SIZE 16
+#define AES_MAX_DIGEST_SIZE 128
+#define AES_DEFAULT_DIGEST_ALGORITHM "SHA256"
+
+struct PARCSymmetricKeySigner {
+ PARCSymmetricKeyStore *keyStore;
+ PARCKeyStore *generalKeyStore;
+
+ PARCCryptoHash *secretKeyHash;
+ PARCCryptoHasher *hasher;
+ PARCCryptoHasherInterface hasherFunctor;
+ PARCCryptoHashType hashType;
+
+ unsigned hashLength;
+ const EVP_MD *opensslMd;
+};
+
+// ==================================================
+// HMAC implementation
+
+static void *
+_hmacCreate(void *env)
+{
+ PARCSymmetricKeySigner *signer = (PARCSymmetricKeySigner *) env;
+#if OPENSSL_VERSION_NUMBER >= 0x10100000L
+ HMAC_CTX *ctx = HMAC_CTX_new();
+ HMAC_CTX_reset(ctx);
+#else
+ // HMAC_Init_ex seems to overrun the size of HMAC_CTX, so make it bigger
+ HMAC_CTX *ctx = parcMemory_Allocate(sizeof(HMAC_CTX) * 2);
+ assertNotNull(ctx, "parcMemory_Allocate(%zu) returned NULL for HMAC_CTX", sizeof(HMAC_CTX) * 2);
+ HMAC_CTX_init(ctx);
+#endif
+
+ // Now initialize it with our digest and key, so in hmac_init we can avoid using those
+ PARCBuffer *secretKey = parcSymmetricKeyStore_GetKey(signer->keyStore);
+ assertTrue(parcBuffer_Remaining(secretKey) < 512, "The keystore secret key cannot be longer than %d", 512);
+
+ HMAC_Init_ex(ctx, parcByteArray_Array(parcBuffer_Array(secretKey)), (int) parcBuffer_Remaining(secretKey), signer->opensslMd, NULL);
+
+ return ctx;
+}
+
+static int
+_hmacInit(void *ctx)
+{
+ // reset the HMAC state with NULLs, so we'll re-use the values we had from setup.
+ HMAC_Init_ex((HMAC_CTX *) ctx, NULL, 0, NULL, NULL);
+ return 0;
+}
+
+static int
+_hmacUpdate(void *ctx, const void *buffer, size_t length)
+{
+ HMAC_Update(ctx, buffer, length);
+ return 0;
+}
+
+static PARCBuffer*
+_hmacFinalize(void *ctx)
+{
+ uint8_t buffer[EVP_MAX_MD_SIZE];
+ unsigned length;
+ HMAC_Final(ctx, buffer, &length);
+
+ PARCBuffer *output = parcBuffer_Allocate(length);
+ parcBuffer_PutArray(output, length, buffer);
+
+ return output;
+}
+
+static void
+_hmacDestroy(void **ctxPtr)
+{
+#if (OPENSSL_VERSION_NUMBER >= 0x1010003fL)
+ HMAC_CTX_free(*ctxPtr);
+#else
+ HMAC_CTX_cleanup(*ctxPtr);
+#endif
+ parcMemory_Deallocate((void **) ctxPtr);
+ *ctxPtr = NULL;
+}
+
+static PARCCryptoHasherInterface functor_hmac = {
+ .functor_env = NULL,
+ .hasher_setup = _hmacCreate,
+ .hasher_init = _hmacInit,
+ .hasher_update = _hmacUpdate,
+ .hasher_finalize = _hmacFinalize,
+ .hasher_destroy = _hmacDestroy
+};
+
+static bool
+_parcSymmetricKeySigner_Finalize(PARCSymmetricKeySigner **instancePtr)
+{
+ assertNotNull(instancePtr, "Parameter must be a non-null pointer to a PARCSymmetricKeySigner pointer.");
+ PARCSymmetricKeySigner *signer = (PARCSymmetricKeySigner *) *instancePtr;
+ if (signer->secretKeyHash != NULL) {
+ parcCryptoHash_Release(&signer->secretKeyHash);
+ }
+ if (signer->hasher != NULL) {
+ parcCryptoHasher_Release(&signer->hasher);
+ }
+
+ if (signer->keyStore != NULL) {
+ parcSymmetricKeyStore_Release(&signer->keyStore);
+ }
+ if (signer->generalKeyStore != NULL) {
+ parcKeyStore_Release(&signer->generalKeyStore);
+ }
+
+ return true;
+}
+
+parcObject_ImplementAcquire(parcSymmetricKeySigner, PARCSymmetricKeySigner);
+parcObject_ImplementRelease(parcSymmetricKeySigner, PARCSymmetricKeySigner);
+
+parcObject_Override(PARCSymmetricKeySigner, PARCObject,
+ .destructor = (PARCObjectDestructor *) _parcSymmetricKeySigner_Finalize);
+
+void
+parcSymmetricKeySigner_AssertValid(const PARCSymmetricKeySigner *instance)
+{
+ assertTrue(parcSymmetricKeySigner_IsValid(instance),
+ "PARCSymmetricKeySigner is not valid.");
+}
+
+PARCSymmetricKeySigner *
+parcSymmetricKeySigner_Create(PARCSymmetricKeyStore *keyStore, PARCCryptoHashType hmacHashType)
+{
+ PARCSymmetricKeySigner *result = parcObject_CreateInstance(PARCSymmetricKeySigner);
+
+ if (result != NULL) {
+ result->hashType = hmacHashType;
+ switch (hmacHashType) {
+ case PARCCryptoHashType_SHA256:
+ result->hashLength = SHA256_DIGEST_LENGTH;
+ result->opensslMd = EVP_sha256();
+ break;
+
+ case PARCCryptoHashType_SHA512:
+ result->hashLength = SHA512_DIGEST_LENGTH;
+ result->opensslMd = EVP_sha512();
+ break;
+
+ default:
+ parcObject_Release((void **) &result);
+ trapIllegalValue(hmacHashType, "Unknown HMAC hash type: %d", hmacHashType);
+ }
+
+ // the signer key digest is SHA256, independent of the HMAC digest
+ result->secretKeyHash = parcSymmetricKeyStore_GetVerifierKeyDigest(keyStore);
+ result->keyStore = parcSymmetricKeyStore_Acquire(keyStore);
+ result->generalKeyStore = parcKeyStore_Create(result->keyStore, PARCSymmetricKeyStoreAsKeyStore);
+
+ // create the functor from the template then specialize it to this keystore.
+ // This depends on keystore->secret_key being set. It will cause a callback
+ // into hmac_setup()
+ result->hasherFunctor = functor_hmac;
+ result->hasherFunctor.functor_env = result;
+ result->hasher = parcCryptoHasher_CustomHasher(hmacHashType, result->hasherFunctor);
+ }
+
+ return result;
+}
+
+bool
+parcSymmetricKeySigner_IsValid(const PARCSymmetricKeySigner *instance)
+{
+ bool result = false;
+
+ if (instance != NULL) {
+ result = true;
+ }
+
+ return result;
+}
+
+static PARCSigningAlgorithm
+_getSigningAlgorithm(PARCSymmetricKeySigner *signer)
+{
+ return PARCSigningAlgorithm_HMAC;
+}
+
+static PARCCryptoHashType
+_getCryptoHashType(PARCSymmetricKeySigner *signer)
+{
+ return signer->hashType;
+}
+
+static PARCCryptoHasher *
+_getCryptoHasher(PARCSymmetricKeySigner *signer)
+{
+ return signer->hasher;
+}
+
+static PARCKeyStore *
+_getKeyStore(PARCSymmetricKeySigner *signer)
+{
+ return signer->generalKeyStore;
+}
+
+// ==================================================
+// implementation
+
+/**
+ * wrap the HMAC in digestToSign in a PARCSignature
+ *
+ * @param hashToSign is the HMAC computed by the our PARCCryptoHasher.
+ */
+static PARCSignature *
+_signDigest(PARCSymmetricKeySigner *interfaceContext, const PARCCryptoHash *hashToSign)
+{
+ // The digest computed via our hash function (hmac) is the actual signature.
+ // just need to wrap it up with the right parameters.
+ PARCBuffer *signatureBits = parcBuffer_Copy(parcCryptoHash_GetDigest(hashToSign));
+ PARCSignature *result = parcSignature_Create(_getSigningAlgorithm(interfaceContext), parcCryptoHash_GetDigestType(hashToSign), signatureBits);
+ parcBuffer_Release(&signatureBits);
+ return result;
+}
+
+PARCSigningInterface *PARCSymmetricKeySignerAsSigner = &(PARCSigningInterface) {
+ .GetCryptoHashType = (PARCCryptoHashType (*)(void *))_getCryptoHashType,
+ .GetCryptoHasher = (PARCCryptoHasher * (*)(void *))_getCryptoHasher,
+ .SignDigest = (PARCSignature * (*)(void *, const PARCCryptoHash *))_signDigest,
+ .GetSigningAlgorithm = (PARCSigningAlgorithm (*)(void *))_getSigningAlgorithm,
+ .GetKeyStore = (PARCKeyStore * (*)(void *))_getKeyStore,
+};