所以，我正在尝试将一段C++代码翻译成php。 这个C++代码来自外部来源，而我的C++和解密知识都很缺乏，可以这么说。
源C++代码如下：
void parser_t::decrypt(buffer_t &replay_data, const unsigned char *key_data) {
/*\
|*| Performs an in place decryption of the replay using the given key.
|*| The decryption is a (broken) variant of CBC decryption and is performed as follows:
|*| -# Set the variable previous_block (with size of 16 bytes) to 0
|*| -# Decrypt a block with the given key
|*| -# XOR the block with the previous (decrypted) block
|*| -# Go back to step 2, until there are no more blocks.
\*/
BF_KEY key = {{0}};
BF_set_key(&key, 16, key_data);
const int block_size = 8;
size_t padding_size = (block_size - (replay_data.size() % block_size));
if (padding_size != 0) {
size_t required_size = replay_data.size() + padding_size;
replay_data.resize(required_size, 0);
}
unsigned char previous[block_size] = {0};
for (auto it = replay_data.begin(); it != replay_data.end(); it += block_size) {
unsigned char decrypted[block_size] = { 0 };
BF_ecb_encrypt(reinterpret_cast<unsigned char*>(&(*it)), decrypted, &key, BF_DECRYPT);
std::transform(previous, previous + block_size, decrypted, decrypted, std::bit_xor<unsigned char>());
std::copy_n(decrypted, block_size, previous);
std::copy_n(decrypted, block_size, reinterpret_cast<unsigned char*>(&(*it)));
}
if (padding_size != 0) {
size_t original_size = replay_data.size() - padding_size;
replay_data.resize(original_size, 0);
}
}
我目前所拥有的内容：
function decrypt($data){ // $data is a encrypted string
$key = array(0xDE, <.....>, 0xEF); // (16 entries in the array)
//BF_KEY key = {{0}}; // ?
//BF_set_key(&key, 16, key_data); // ?
$block_size = 8;
$padding_size = ($block_size - (strlen($data) % $block_size));
if ($padding_size != 0) {
$required_size = strlen($data) + $padding_size;
//replay_data.resize(required_size, 0);
// Seems unnecessary in php? string lengths are pretty dynamic.
}
$keyString = '';
for($i = 0; $i < count($key); $i++){
$keyString .= chr($key[$i]);
}
$output = '';
for ($i = 0; $i < stlen($data); $i += $block_size) {
$char = array(0, 0, 0, 0, 0, 0, 0, 0); // ?
$decrypted_piece = mcrypt_decrypt(MCRYPT_BLOWFISH, $keyString, $data, "cbc"); // ??
// And this is where I completely get lost.
$output = transform($in, $start, $end, $in2);
}
}
function transform($in, $start, $end, $in2){
$out = ''; // Yea, that won't work...
for($x = $start; $x < $end; $x++){
$out[$x] = $in[$x] ^ $in2[$x];
}
return $output
}
我意识到我基本上是在请求你们帮我做某些事情，但我真的被那个for(auto it...)的内容卡住了。
以下是可能会有所帮助的提示/解释：
- 在这种情况下，BF_ecb_encrypt是做什么的？（使用伪代码或甚至是php）（“不要求成品”）
- 我的transform翻译是否正确？
- {{0}}，BF_set_key(&key, 16, key_data)是什么？
- reinterpret_cast(&(*it))是什么？
我确实看过这些文档页面，但没有任何帮助。
完整的源代码可以在github上找到（链接）。
这段特定的代码来自src/parser.cpp
buffer_t似乎是：typedef std::vector<uint8_t> buffer_t;。我试图转换的文件可以在这里（或直接链接）找到。 - Cerbrus