import KgmCryptoModule from '@/KgmWasm/KgmWasmBundle'; import { MergeUint8Array } from '@/utils/MergeUint8Array'; // 每次处理 2M 的数据 const DECRYPTION_BUF_SIZE = 2 *1024 * 1024; export interface KGMDecryptionResult { success: boolean; data: Uint8Array; error: string; } /** * 解密一个 KGM 加密的文件。 * * 如果检测并解密成功,返回解密后的 Uint8Array 数据。 * @param {ArrayBuffer} kgmBlob 读入的文件 Blob */ export async function DecryptKgmWasm(kgmBlob: ArrayBuffer, ext: string): Promise { const result: KGMDecryptionResult = { success: false, data: new Uint8Array(), error: '' }; // 初始化模组 let KgmCrypto: any; try { KgmCrypto = await KgmCryptoModule(); } catch (err: any) { result.error = err?.message || 'wasm 加载失败'; return result; } if (!KgmCrypto) { result.error = 'wasm 加载失败'; return result; } // 申请内存块,并文件末端数据到 WASM 的内存堆 let kgmBuf = new Uint8Array(kgmBlob); const pQmcBuf = KgmCrypto._malloc(DECRYPTION_BUF_SIZE); KgmCrypto.writeArrayToMemory(kgmBuf.slice(0, DECRYPTION_BUF_SIZE), pQmcBuf); // 进行解密初始化 const headerSize = KgmCrypto.preDec(pQmcBuf, DECRYPTION_BUF_SIZE, ext); console.log(headerSize); kgmBuf = kgmBuf.slice(headerSize); const decryptedParts = []; let offset = 0; let bytesToDecrypt = kgmBuf.length; while (bytesToDecrypt > 0) { const blockSize = Math.min(bytesToDecrypt, DECRYPTION_BUF_SIZE); // 解密一些片段 const blockData = new Uint8Array(kgmBuf.slice(offset, offset + blockSize)); KgmCrypto.writeArrayToMemory(blockData, pQmcBuf); KgmCrypto.decBlob(pQmcBuf, blockSize, offset); decryptedParts.push(KgmCrypto.HEAPU8.slice(pQmcBuf, pQmcBuf + blockSize)); offset += blockSize; bytesToDecrypt -= blockSize; } KgmCrypto._free(pQmcBuf); result.data = MergeUint8Array(decryptedParts); result.success = true; return result; }