wx-ding-aes/dist/pkcs7.js

Wechat open platform, Enterprise wechat and DingTalk AES decode library.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
/**
 * PKCS7 模块，用于进行 PKCS7 偏移的编码和解码
 * @module pkcs7
 */
const defaultSize = 32;
/**
 * @description PKCS7 编码
 * @author beary
 * @param buf { Buffer } 需要进行编码的 Buffer
 * @param blockSize { string } 偏移块大小
 */
exports.encode = (buf, blockSize) => {
    blockSize = blockSize || defaultSize;
    const padLen = (blockSize - buf.length % blockSize) || blockSize;
    const padBuf = Buffer
        .alloc(buf.length + padLen)
        .fill(padLen);
    buf.copy(padBuf);
    return padBuf;
};
/**
 * @description PKCS7 解码
 * @author beary
 * @param buf { Buffer } 需要进行解码的 Buffer
 * @param blockSize { string } 偏移块大小
 */
exports.decode = (buf, blockSize) => {
    blockSize = blockSize || defaultSize;
    let padLen = buf[buf.length - 1];
    if (padLen < 1 || padLen > blockSize)
        padLen = 0;
    return buf.slice(0, buf.length - padLen);
};