kgg-dec/third-party/aes/aes_openssl.cpp

44 lines
1.1 KiB
C++

#include <cassert>
#include <cstring>
#include "aes.h"
namespace AES {
bool AES_init_ctx_iv(AES_ctx* ctx, const uint8_t* key, const uint8_t* iv) {
ctx->cipher_ctx = EVP_CIPHER_CTX_new();
if (!ctx->cipher_ctx) {
return false;
}
if (EVP_DecryptInit_ex(ctx->cipher_ctx, EVP_aes_128_cbc(), nullptr, key, iv) != 1) {
AES_cleanup(ctx);
return false;
}
EVP_CIPHER_CTX_set_padding(ctx->cipher_ctx, 0);
return true;
}
size_t AES_CBC_encrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length) {
// not implemented
return 0;
}
size_t AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length) {
auto buf_len = static_cast<int>(length);
EVP_DecryptUpdate(ctx->cipher_ctx, buf, &buf_len, buf, buf_len);
assert(buf_len == length && "AES_CBC_decrypt_buffer: buffer length mismatch");
return buf_len;
}
bool AES_cleanup(AES_ctx* ctx) {
if (ctx->cipher_ctx) {
EVP_CIPHER_CTX_free(ctx->cipher_ctx);
ctx->cipher_ctx = nullptr;
}
return true;
}
} // namespace AES