aes_util: Fix error involving reads of less than 0x10

Issues with block size are fixed by making all reads minimum length of 0x10
This commit is contained in:
Zach Hilman 2018-08-25 18:56:25 -04:00
parent faa9e066ab
commit 99fbcb3bf2
1 changed files with 14 additions and 0 deletions

View File

@ -82,11 +82,25 @@ void AESCipher<Key, KeySize>::Transcode(const u8* src, size_t size, u8* dest, Op
}
} else {
const auto block_size = mbedtls_cipher_get_block_size(context);
if (size < block_size) {
std::vector<u8> block(block_size);
std::memcpy(block.data(), src, size);
Transcode(block.data(), block.size(), block.data(), op);
std::memcpy(dest, block.data(), size);
return;
}
for (size_t offset = 0; offset < size; offset += block_size) {
auto length = std::min<size_t>(block_size, size - offset);
mbedtls_cipher_update(context, src + offset, length, dest + offset, &written);
if (written != length) {
if (length < block_size) {
std::vector<u8> block(block_size);
std::memcpy(block.data(), src + offset, length);
Transcode(block.data(), block.size(), block.data(), op);
std::memcpy(dest + offset, block.data(), length);
return;
}
LOG_WARNING(Crypto, "Not all data was decrypted requested={:016X}, actual={:016X}.",
length, written);
}