miscreant/release/providers/webcrypto/aes_ctr.js

Misuse resistant symmetric encryption library providing AES-SIV (RFC 5297), AES-PMAC-SIV, and STREAM constructions

"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
Object.defineProperty(exports, "__esModule", { value: true });
/**
 * AES-CTR using a WebCrypto (or similar) API
 */
class WebCryptoAesCtr {
    constructor(key, crypto) {
        this.key = key;
        this.crypto = crypto;
    }
    static importKey(crypto, keyData) {
        return __awaiter(this, void 0, void 0, function* () {
            // Only AES-128 and AES-256 supported. AES-192 is not.
            if (keyData.length !== 16 && keyData.length !== 32) {
                throw new Error(`Miscreant: invalid key length: ${keyData.length} (expected 16 or 32 bytes)`);
            }
            const key = yield crypto.subtle.importKey("raw", keyData, "AES-CTR", false, ["encrypt"]);
            return new WebCryptoAesCtr(key, crypto);
        });
    }
    encryptCtr(iv, plaintext) {
        return __awaiter(this, void 0, void 0, function* () {
            const ciphertext = yield this.crypto.subtle.encrypt({ name: "AES-CTR", counter: iv, length: 16 }, this.key, plaintext);
            return new Uint8Array(ciphertext);
        });
    }
    clear() {
        // TODO: actually clear something. Do we need to?
        return this;
    }
}
exports.default = WebCryptoAesCtr;