Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2016 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 | |
Jason Macnak | d54a535 | 2023-12-08 01:21:48 +0000 | [diff] [blame] | 17 | #include "gfxstream/guest/ChecksumCalculator.h" |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 18 | |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 19 | #include <string.h> |
| 20 | |
Jason Macnak | d54a535 | 2023-12-08 01:21:48 +0000 | [diff] [blame] | 21 | namespace gfxstream { |
| 22 | namespace guest { |
| 23 | |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 24 | // Checklist when implementing new protocol: |
| 25 | // 1. update CHECKSUMHELPER_MAX_VERSION |
Yurii Zubrytskyi | ac0e8ca | 2016-11-04 11:57:02 -0700 | [diff] [blame] | 26 | // 2. update ChecksumCalculator::Sizes enum |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 27 | // 3. update checksumByteSize() |
| 28 | // 4. update addBuffer, writeChecksum, resetChecksum, validate |
| 29 | |
| 30 | // change CHECKSUMHELPER_MAX_VERSION when you want to update the protocol version |
| 31 | #define CHECKSUMHELPER_MAX_VERSION 1 |
| 32 | |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 33 | // utility macros to create checksum string at compilation time |
| 34 | #define CHECKSUMHELPER_VERSION_STR_PREFIX "ANDROID_EMU_CHECKSUM_HELPER_v" |
| 35 | #define CHECKSUMHELPER_MACRO_TO_STR(x) #x |
| 36 | #define CHECKSUMHELPER_MACRO_VAL_TO_STR(x) CHECKSUMHELPER_MACRO_TO_STR(x) |
| 37 | |
| 38 | static const uint32_t kMaxVersion = CHECKSUMHELPER_MAX_VERSION; |
| 39 | static const char* kMaxVersionStrPrefix = CHECKSUMHELPER_VERSION_STR_PREFIX; |
| 40 | static const char* kMaxVersionStr = CHECKSUMHELPER_VERSION_STR_PREFIX CHECKSUMHELPER_MACRO_VAL_TO_STR(CHECKSUMHELPER_MAX_VERSION); |
| 41 | |
| 42 | #undef CHECKSUMHELPER_MAX_VERSION |
| 43 | #undef CHECKSUMHELPER_VERSION_STR_PREFIX |
| 44 | #undef CHECKSUMHELPER_MACRO_TO_STR |
| 45 | #undef CHECKSUMHELPER_MACRO_VAL_TO_STR |
| 46 | |
| 47 | uint32_t ChecksumCalculator::getMaxVersion() {return kMaxVersion;} |
| 48 | const char* ChecksumCalculator::getMaxVersionStr() {return kMaxVersionStr;} |
| 49 | const char* ChecksumCalculator::getMaxVersionStrPrefix() {return kMaxVersionStrPrefix;} |
| 50 | |
| 51 | bool ChecksumCalculator::setVersion(uint32_t version) { |
| 52 | if (version > kMaxVersion) { // unsupported version |
| 53 | LOG_CHECKSUMHELPER("%s: ChecksumCalculator Set Unsupported version Version %d\n", |
| 54 | __FUNCTION__, m_version); |
| 55 | return false; |
| 56 | } |
| 57 | if (m_isEncodingChecksum) { // setVersion is called in the middle of encoding checksums |
| 58 | LOG_CHECKSUMHELPER("%s: called between addBuffer and writeChecksum\n", |
| 59 | __FUNCTION__); |
| 60 | return false; |
| 61 | } |
| 62 | m_version = version; |
| 63 | LOG_CHECKSUMHELPER("%s: ChecksumCalculator Set Version %d\n", __FUNCTION__, |
| 64 | m_version); |
| 65 | return true; |
| 66 | } |
| 67 | |
| 68 | size_t ChecksumCalculator::checksumByteSize() const { |
| 69 | switch (m_version) { |
| 70 | case 0: |
| 71 | return 0; |
| 72 | case 1: |
| 73 | return sizeof(uint32_t) + sizeof(m_numWrite); |
| 74 | default: |
| 75 | return 0; |
| 76 | } |
| 77 | } |
| 78 | |
Yahan Zhou | d906928 | 2016-06-17 17:40:14 -0700 | [diff] [blame] | 79 | ChecksumCalculator::ChecksumCalculator() |
| 80 | : m_version(0) |
| 81 | , m_numRead(0) |
| 82 | , m_numWrite(0) |
| 83 | , m_isEncodingChecksum(false) |
| 84 | , m_v1BufferTotalLength(0) |
| 85 | { |
| 86 | } |
| 87 | |
Lingfeng Yang | 764a1fc | 2019-08-22 12:16:11 -0700 | [diff] [blame] | 88 | void ChecksumCalculator::addBuffer(const void*, size_t packetLen) { |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 89 | m_isEncodingChecksum = true; |
| 90 | switch (m_version) { |
| 91 | case 1: |
| 92 | m_v1BufferTotalLength += packetLen; |
| 93 | break; |
| 94 | } |
| 95 | } |
| 96 | |
| 97 | bool ChecksumCalculator::writeChecksum(void* outputChecksum, size_t outputChecksumLen) { |
| 98 | if (outputChecksumLen < checksumByteSize()) return false; |
| 99 | char *checksumPtr = (char *)outputChecksum; |
| 100 | switch (m_version) { |
| 101 | case 1: { // protocol v1 is to reverse the packetLen and write it at the end |
Yahan Zhou | e222fd5 | 2016-03-16 12:41:08 -0700 | [diff] [blame] | 102 | uint32_t val = computeV1Checksum(); |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 103 | memcpy(checksumPtr, &val, sizeof(val)); |
| 104 | memcpy(checksumPtr+sizeof(val), &m_numWrite, sizeof(m_numWrite)); |
| 105 | break; |
| 106 | } |
| 107 | } |
| 108 | resetChecksum(); |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 109 | m_numWrite++; |
| 110 | return true; |
| 111 | } |
| 112 | |
| 113 | void ChecksumCalculator::resetChecksum() { |
| 114 | switch (m_version) { |
| 115 | case 1: |
| 116 | m_v1BufferTotalLength = 0; |
| 117 | break; |
| 118 | } |
| 119 | m_isEncodingChecksum = false; |
| 120 | } |
| 121 | |
Yahan Zhou | e222fd5 | 2016-03-16 12:41:08 -0700 | [diff] [blame] | 122 | bool ChecksumCalculator::validate(const void* expectedChecksum, size_t expectedChecksumLen) { |
| 123 | size_t checksumSize = checksumByteSize(); |
| 124 | if (expectedChecksumLen != checksumSize) { |
| 125 | m_numRead++; |
| 126 | resetChecksum(); |
| 127 | return false; |
| 128 | } |
Yurii Zubrytskyi | ac0e8ca | 2016-11-04 11:57:02 -0700 | [diff] [blame] | 129 | bool isValid; |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 130 | switch (m_version) { |
| 131 | case 1: { |
Yurii Zubrytskyi | ac0e8ca | 2016-11-04 11:57:02 -0700 | [diff] [blame] | 132 | const uint32_t val = computeV1Checksum(); |
| 133 | isValid = 0 == memcmp(&val, expectedChecksum, sizeof(val)) && |
| 134 | 0 == memcmp(&m_numRead, |
| 135 | static_cast<const char*>(expectedChecksum) + |
| 136 | sizeof(val), |
| 137 | sizeof(m_numRead)); |
| 138 | |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 139 | break; |
| 140 | } |
Yurii Zubrytskyi | ac0e8ca | 2016-11-04 11:57:02 -0700 | [diff] [blame] | 141 | default: |
| 142 | isValid = true; // No checksum is a valid checksum. |
| 143 | break; |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 144 | } |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 145 | m_numRead++; |
Yahan Zhou | e222fd5 | 2016-03-16 12:41:08 -0700 | [diff] [blame] | 146 | resetChecksum(); |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 147 | return isValid; |
| 148 | } |
| 149 | |
Yahan Zhou | e222fd5 | 2016-03-16 12:41:08 -0700 | [diff] [blame] | 150 | uint32_t ChecksumCalculator::computeV1Checksum() { |
| 151 | uint32_t revLen = m_v1BufferTotalLength; |
Yahan Zhou | b7f0908 | 2016-03-10 11:45:02 -0800 | [diff] [blame] | 152 | revLen = (revLen & 0xffff0000) >> 16 | (revLen & 0x0000ffff) << 16; |
| 153 | revLen = (revLen & 0xff00ff00) >> 8 | (revLen & 0x00ff00ff) << 8; |
| 154 | revLen = (revLen & 0xf0f0f0f0) >> 4 | (revLen & 0x0f0f0f0f) << 4; |
| 155 | revLen = (revLen & 0xcccccccc) >> 2 | (revLen & 0x33333333) << 2; |
| 156 | revLen = (revLen & 0xaaaaaaaa) >> 1 | (revLen & 0x55555555) << 1; |
| 157 | return revLen; |
| 158 | } |
Jason Macnak | d54a535 | 2023-12-08 01:21:48 +0000 | [diff] [blame] | 159 | |
| 160 | } // namespace guest |
Joshua Duong | d2b8f0c | 2024-02-07 21:20:32 +0000 | [diff] [blame] | 161 | } // namespace gfxstream |