1 /*
2 * Copyright (C) 2019 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "TokenHasher.h"
18
19 #include "NeuralNetworks.h"
20
21 #include <android-base/logging.h>
22 #include <openssl/sha.h>
23
24 namespace android {
25 namespace nn {
26
TokenHasher(const uint8_t * token)27 TokenHasher::TokenHasher(const uint8_t* token) : mIsError(token == nullptr) {
28 if (mIsError) {
29 return;
30 }
31 if (SHA256_Init(&mHasher) == 0 ||
32 SHA256_Update(&mHasher, token, ANEURALNETWORKS_BYTE_SIZE_OF_CACHE_TOKEN) == 0) {
33 mIsError = true;
34 }
35 }
36
update(const void * bytes,size_t length)37 bool TokenHasher::update(const void* bytes, size_t length) {
38 CHECK(!mIsError) << "Calling update on an token in error state";
39 if (SHA256_Update(&mHasher, bytes, length) == 0) {
40 mIsError = true;
41 return false;
42 }
43 return true;
44 }
45
finish()46 bool TokenHasher::finish() {
47 CHECK(!mIsError) << "Calling finish on an token in error state";
48 static_assert(SHA256_DIGEST_LENGTH == ANEURALNETWORKS_BYTE_SIZE_OF_CACHE_TOKEN,
49 "SHA256_DIGEST_LENGTH != ANEURALNETWORKS_BYTE_SIZE_OF_CACHE_TOKEN");
50 mToken.resize(ANEURALNETWORKS_BYTE_SIZE_OF_CACHE_TOKEN);
51 if (SHA256_Final(mToken.data(), &mHasher) == 0) {
52 mToken.clear();
53 mIsError = true;
54 return false;
55 }
56 return true;
57 }
58
getCacheToken() const59 const uint8_t* TokenHasher::getCacheToken() const {
60 if (mIsError) {
61 return nullptr;
62 } else {
63 CHECK(!mToken.empty());
64 return mToken.data();
65 }
66 }
67
68 } // namespace nn
69 } // namespace android
70