Viewing File: /home/ubuntu/efiexchange-node-base/node_modules/ethereum-cryptography/esm/aes.js
import { crypto as cr } from "@noble/hashes/crypto";
import { concatBytes, equalsBytes } from "./utils.js";
const crypto = { web: cr };
function validateOpt(key, iv, mode) {
if (!mode.startsWith("aes-")) {
throw new Error(`AES submodule doesn't support mode ${mode}`);
}
if (iv.length !== 16) {
throw new Error("AES: wrong IV length");
}
if ((mode.startsWith("aes-128") && key.length !== 16) ||
(mode.startsWith("aes-256") && key.length !== 32)) {
throw new Error("AES: wrong key length");
}
}
async function getBrowserKey(mode, key, iv) {
if (!crypto.web) {
throw new Error("Browser crypto not available.");
}
let keyMode;
if (["aes-128-cbc", "aes-256-cbc"].includes(mode)) {
keyMode = "cbc";
}
if (["aes-128-ctr", "aes-256-ctr"].includes(mode)) {
keyMode = "ctr";
}
if (!keyMode) {
throw new Error("AES: unsupported mode");
}
const wKey = await crypto.web.subtle.importKey("raw", key, { name: `AES-${keyMode.toUpperCase()}`, length: key.length * 8 }, true, ["encrypt", "decrypt"]);
// node.js uses whole 128 bit as a counter, without nonce, instead of 64 bit
// recommended by NIST SP800-38A
return [wKey, { name: `aes-${keyMode}`, iv, counter: iv, length: 128 }];
}
export async function encrypt(msg, key, iv, mode = "aes-128-ctr", pkcs7PaddingEnabled = true) {
validateOpt(key, iv, mode);
if (crypto.web) {
const [wKey, wOpt] = await getBrowserKey(mode, key, iv);
const cipher = await crypto.web.subtle.encrypt(wOpt, wKey, msg);
// Remove PKCS7 padding on cbc mode by stripping end of message
let res = new Uint8Array(cipher);
if (!pkcs7PaddingEnabled && wOpt.name === "aes-cbc" && !(msg.length % 16)) {
res = res.slice(0, -16);
}
return res;
}
else if (crypto.node) {
const cipher = crypto.node.createCipheriv(mode, key, iv);
cipher.setAutoPadding(pkcs7PaddingEnabled);
return concatBytes(cipher.update(msg), cipher.final());
}
else {
throw new Error("The environment doesn't have AES module");
}
}
async function getPadding(cypherText, key, iv, mode) {
const lastBlock = cypherText.slice(-16);
for (let i = 0; i < 16; i++) {
// Undo xor of iv and fill with lastBlock ^ padding (16)
lastBlock[i] ^= iv[i] ^ 16;
}
const res = await encrypt(lastBlock, key, iv, mode);
return res.slice(0, 16);
}
export async function decrypt(cypherText, key, iv, mode = "aes-128-ctr", pkcs7PaddingEnabled = true) {
validateOpt(key, iv, mode);
if (crypto.web) {
const [wKey, wOpt] = await getBrowserKey(mode, key, iv);
// Add empty padding so Chrome will correctly decrypt message
if (!pkcs7PaddingEnabled && wOpt.name === "aes-cbc") {
const padding = await getPadding(cypherText, key, iv, mode);
cypherText = concatBytes(cypherText, padding);
}
const msg = await crypto.web.subtle.decrypt(wOpt, wKey, cypherText);
const msgBytes = new Uint8Array(msg);
// Safari always ignores padding (if no padding -> broken message)
if (wOpt.name === "aes-cbc") {
const encrypted = await encrypt(msgBytes, key, iv, mode);
if (!equalsBytes(encrypted, cypherText)) {
throw new Error("AES: wrong padding");
}
}
return msgBytes;
}
else if (crypto.node) {
const decipher = crypto.node.createDecipheriv(mode, key, iv);
decipher.setAutoPadding(pkcs7PaddingEnabled);
return concatBytes(decipher.update(cypherText), decipher.final());
}
else {
throw new Error("The environment doesn't have AES module");
}
}
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