1 files changed, 149 insertions, 0 deletions
diff --git a/libccnx-common/ccnx/common/codec/schema_v1/ccnxCodecSchemaV1_HashCodec.c b/libccnx-common/ccnx/common/codec/schema_v1/ccnxCodecSchemaV1_HashCodec.c
new file mode 100644
index 00000000..23a559cc
--- /dev/null
+++ b/libccnx-common/ccnx/common/codec/schema_v1/ccnxCodecSchemaV1_HashCodec.c
@@ -0,0 +1,149 @@
+/*
+ * 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 <stdlib.h>
+
+#include <LongBow/runtime.h>
+
+#include <parc/algol/parc_Memory.h>
+#include <parc/algol/parc_Buffer.h>
+
+#include <ccnx/common/codec/schema_v1/ccnxCodecSchemaV1_Types.h>
+#include <ccnx/common/codec/ccnxCodec_TlvUtilities.h>
+
+#include <ccnx/common/codec/schema_v1/ccnxCodecSchemaV1_HashCodec.h>
+
+/**
+ * These are the accepted sizes for the pre-defined hash types.
+ * Hash TLVs with lengths that do not match one of these values will be deemed
+ * invalid and not parse correctly.
+ */
+static const size_t _PARCCryptoHashType_SHA256_Sizes[] = { 32 };
+static const size_t _PARCCryptoHashType_SHA512_Sizes[] = { 32, 64 };
+
+static bool
+_ccnxCodecSchemaV1HashCodec_ValidHashSize(size_t size, size_t numSizes, size_t sizes[numSizes])
+{
+    for (size_t i = 0; i < numSizes; i++) {
+        if (sizes[i] == size) {
+            return true;
+        }
+    }
+    return false;
+}
+
+ssize_t
+ccnxCodecSchemaV1HashCodec_Encode(CCNxCodecTlvEncoder *encoder, const PARCCryptoHash *hash)
+{
+    PARCBuffer *digest = parcCryptoHash_GetDigest(hash);
+    PARCCryptoHashType hashType = parcCryptoHash_GetDigestType(hash);
+    size_t digestLength = parcBuffer_Remaining(digest);
+
+    uint16_t tlvHashType = CCNxCodecSchemaV1Types_HashType_App;
+    bool validHash = true;
+    switch (hashType) {
+        case PARCCryptoHashType_SHA256:
+            tlvHashType = CCNxCodecSchemaV1Types_HashType_SHA256;
+            validHash = _ccnxCodecSchemaV1HashCodec_ValidHashSize(digestLength,
+                                                                  sizeof(_PARCCryptoHashType_SHA256_Sizes) / sizeof(size_t), (size_t *) _PARCCryptoHashType_SHA256_Sizes);
+            break;
+        case PARCCryptoHashType_SHA512:
+            tlvHashType = CCNxCodecSchemaV1Types_HashType_SHA512;
+            validHash = _ccnxCodecSchemaV1HashCodec_ValidHashSize(digestLength,
+                                                                  sizeof(_PARCCryptoHashType_SHA512_Sizes) / sizeof(size_t), (size_t *) _PARCCryptoHashType_SHA512_Sizes);
+            break;
+        default:
+            break;
+    }
+
+    if (validHash) {
+        return ccnxCodecTlvEncoder_AppendBuffer(encoder, tlvHashType, digest);
+    } else {
+        CCNxCodecError *error = ccnxCodecError_Create(TLV_MISSING_MANDATORY, __func__, __LINE__, ccnxCodecTlvEncoder_Position(encoder));
+        ccnxCodecTlvEncoder_SetError(encoder, error);
+        ccnxCodecError_Release(&error);
+
+        return -1;
+    }
+}
+
+static bool
+_ccnxCodecSchemaV1HashCodec_ValidHash(uint16_t hashType, uint16_t hashSize)
+{
+    bool validHash = true;
+
+    switch (hashType) {
+        case CCNxCodecSchemaV1Types_HashType_SHA256:
+            validHash = _ccnxCodecSchemaV1HashCodec_ValidHashSize(hashSize,
+                                                                  sizeof(_PARCCryptoHashType_SHA256_Sizes) / sizeof(size_t), (size_t *) _PARCCryptoHashType_SHA256_Sizes);
+            break;
+        case CCNxCodecSchemaV1Types_HashType_SHA512:
+            validHash = _ccnxCodecSchemaV1HashCodec_ValidHashSize(hashSize,
+                                                                  sizeof(_PARCCryptoHashType_SHA512_Sizes) / sizeof(size_t), (size_t *) _PARCCryptoHashType_SHA512_Sizes);
+            break;
+        default:
+            break;
+    }
+
+    return validHash;
+}
+
+PARCCryptoHash *
+ccnxCodecSchemaV1HashCodec_DecodeValue(CCNxCodecTlvDecoder *decoder, size_t limit)
+{
+    PARCCryptoHash *hash = NULL;
+    uint16_t hashType = 0;
+    uint16_t length = 0;
+
+    if (ccnxCodecTlvDecoder_EnsureRemaining(decoder, 4)) {
+        hashType = ccnxCodecTlvDecoder_GetType(decoder);
+        length = ccnxCodecTlvDecoder_GetLength(decoder);
+
+        if (length > limit) {
+            CCNxCodecError *error = ccnxCodecError_Create(TLV_MISSING_MANDATORY, __func__, __LINE__, ccnxCodecTlvDecoder_Position(decoder));
+            ccnxCodecTlvDecoder_SetError(decoder, error);
+            ccnxCodecError_Release(&error);
+            return NULL;
+        }
+
+        if (ccnxCodecTlvDecoder_EnsureRemaining(decoder, length)) {
+            PARCBuffer *value = ccnxCodecTlvDecoder_GetValue(decoder, length);
+            switch (hashType) {
+                case CCNxCodecSchemaV1Types_HashType_SHA256:
+                    hash = parcCryptoHash_Create(PARCCryptoHashType_SHA256, value);
+                    break;
+                case CCNxCodecSchemaV1Types_HashType_SHA512:
+                    hash = parcCryptoHash_Create(PARCCryptoHashType_SHA512, value);
+                    break;
+                case CCNxCodecSchemaV1Types_HashType_App:
+                    hash = parcCryptoHash_Create(PARCCryptoHashType_NULL, value);
+                    break;
+            }
+            parcBuffer_Release(&value);
+        }
+    }
+
+    // Verify the hash size, if one was parsed correctly.
+    if (hash != NULL && !_ccnxCodecSchemaV1HashCodec_ValidHash(hashType, length)) {
+        parcCryptoHash_Release(&hash);
+    }
+
+    return hash;
+}