Cleanup for the cryptographic algorithms that are not supported by Su…

…btleCrypto

core/crypto/aes.js

@@ -0,0 +1,178 @@
+export class AESECBCipher {
+    constructor() {
+        this._key = null;
+    }
+
+    get algorithm() {
+        return { name: "AES-ECB" };
+    }
+
+    static async importKey(key, _algorithm, extractable, keyUsages) {
+        const cipher = new AESECBCipher;
+        await cipher._importKey(key, extractable, keyUsages);
+        return cipher;
+    }
+
+    async _importKey(key, extractable, keyUsages) {
+        this._key = await window.crypto.subtle.importKey(
+            "raw", key, {name: "AES-CBC"}, extractable, keyUsages);
+    }
+
+    async encrypt(_algorithm, plaintext) {
+        const x = new Uint8Array(plaintext);
+        if (x.length % 16 !== 0 || this._key === null) {
+            return null;
+        }
+        const n = x.length / 16;
+        for (let i = 0; i < n; i++) {
+            const y = new Uint8Array(await window.crypto.subtle.encrypt({
+                name: "AES-CBC",
+                iv: new Uint8Array(16),
+            }, this._key, x.slice(i * 16, i * 16 + 16))).slice(0, 16);
+            x.set(y, i * 16);
+        }
+        return x;
+    }
+}
+
+export class AESEAXCipher {
+    constructor() {
+        this._rawKey = null;
+        this._ctrKey = null;
+        this._cbcKey = null;
+        this._zeroBlock = new Uint8Array(16);
+        this._prefixBlock0 = this._zeroBlock;
+        this._prefixBlock1 = new Uint8Array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]);
+        this._prefixBlock2 = new Uint8Array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2]);
+    }
+
+    get algorithm() {
+        return { name: "AES-EAX" };
+    }
+
+    async _encryptBlock(block) {
+        const encrypted = await window.crypto.subtle.encrypt({
+            name: "AES-CBC",
+            iv: this._zeroBlock,
+        }, this._cbcKey, block);
+        return new Uint8Array(encrypted).slice(0, 16);
+    }
+
+    async _initCMAC() {
+        const k1 = await this._encryptBlock(this._zeroBlock);
+        const k2 = new Uint8Array(16);
+        const v = k1[0] >>> 6;
+        for (let i = 0; i < 15; i++) {
+            k2[i] = (k1[i + 1] >> 6) | (k1[i] << 2);
+            k1[i] = (k1[i + 1] >> 7) | (k1[i] << 1);
+        }
+        const lut = [0x0, 0x87, 0x0e, 0x89];
+        k2[14] ^= v >>> 1;
+        k2[15] = (k1[15] << 2) ^ lut[v];
+        k1[15] = (k1[15] << 1) ^ lut[v >> 1];
+        this._k1 = k1;
+        this._k2 = k2;
+    }
+
+    async _encryptCTR(data, counter) {
+        const encrypted = await window.crypto.subtle.encrypt({
+            name: "AES-CTR",
+            counter: counter,
+            length: 128
+        }, this._ctrKey, data);
+        return new Uint8Array(encrypted);
+    }
+
+    async _decryptCTR(data, counter) {
+        const decrypted = await window.crypto.subtle.decrypt({
+            name: "AES-CTR",
+            counter: counter,
+            length: 128
+        }, this._ctrKey, data);
+        return new Uint8Array(decrypted);
+    }
+
+    async _computeCMAC(data, prefixBlock) {
+        if (prefixBlock.length !== 16) {
+            return null;
+        }
+        const n = Math.floor(data.length / 16);
+        const m = Math.ceil(data.length / 16);
+        const r = data.length - n * 16;
+        const cbcData = new Uint8Array((m + 1) * 16);
+        cbcData.set(prefixBlock);
+        cbcData.set(data, 16);
+        if (r === 0) {
+            for (let i = 0; i < 16; i++) {
+                cbcData[n * 16 + i] ^= this._k1[i];
+            }
+        } else {
+            cbcData[(n + 1) * 16 + r] = 0x80;
+            for (let i = 0; i < 16; i++) {
+                cbcData[(n + 1) * 16 + i] ^= this._k2[i];
+            }
+        }
+        let cbcEncrypted = await window.crypto.subtle.encrypt({
+            name: "AES-CBC",
+            iv: this._zeroBlock,
+        }, this._cbcKey, cbcData);
+
+        cbcEncrypted = new Uint8Array(cbcEncrypted);
+        const mac = cbcEncrypted.slice(cbcEncrypted.length - 32, cbcEncrypted.length - 16);
+        return mac;
+    }
+
+    static async importKey(key, _algorithm, _extractable, _keyUsages) {
+        const cipher = new AESEAXCipher;
+        await cipher._importKey(key);
+        return cipher;
+    }
+
+    async _importKey(key) {
+        this._rawKey = key;
+        this._ctrKey = await window.crypto.subtle.importKey(
+            "raw", key, {name: "AES-CTR"}, false, ["encrypt", "decrypt"]);
+        this._cbcKey = await window.crypto.subtle.importKey(
+            "raw", key, {name: "AES-CBC"}, false, ["encrypt"]);
+        await this._initCMAC();
+    }
+
+    async encrypt(algorithm, message) {
+        const ad = algorithm.additionalData;
+        const nonce = algorithm.iv;
+        const nCMAC = await this._computeCMAC(nonce, this._prefixBlock0);
+        const encrypted = await this._encryptCTR(message, nCMAC);
+        const adCMAC = await this._computeCMAC(ad, this._prefixBlock1);
+        const mac = await this._computeCMAC(encrypted, this._prefixBlock2);
+        for (let i = 0; i < 16; i++) {
+            mac[i] ^= nCMAC[i] ^ adCMAC[i];
+        }
+        const res = new Uint8Array(16 + encrypted.length);
+        res.set(encrypted);
+        res.set(mac, encrypted.length);
+        return res;
+    }
+
+    async decrypt(algorithm, data) {
+        const encrypted = data.slice(0, data.length - 16);
+        const ad = algorithm.additionalData;
+        const nonce = algorithm.iv;
+        const mac = data.slice(data.length - 16);
+        const nCMAC = await this._computeCMAC(nonce, this._prefixBlock0);
+        const adCMAC = await this._computeCMAC(ad, this._prefixBlock1);
+        const computedMac = await this._computeCMAC(encrypted, this._prefixBlock2);
+        for (let i = 0; i < 16; i++) {
+            computedMac[i] ^= nCMAC[i] ^ adCMAC[i];
+        }
+        if (computedMac.length !== mac.length) {
+            return null;
+        }
+        for (let i = 0; i < mac.length; i++) {
+            if (computedMac[i] !== mac[i]) {
+                return null;
+            }
+        }
+        const res = await this._decryptCTR(encrypted, nCMAC);
+        return res;
+    }
+}

core/crypto/bigint.js

@@ -0,0 +1,34 @@
+export function modPow(b, e, m) {
+    let r = 1n;
+    b = b % m;
+    while (e > 0n) {
+        if ((e & 1n) === 1n) {
+            r = (r * b) % m;
+        }
+        e = e >> 1n;
+        b = (b * b) % m;
+    }
+    return r;
+}
+
+export function bigIntToU8Array(bigint, padLength=0) {
+    let hex = bigint.toString(16);
+    if (padLength === 0) {
+        padLength = Math.ceil(hex.length / 2);
+    }
+    hex = hex.padStart(padLength * 2, '0');
+    const length = hex.length / 2;
+    const arr = new Uint8Array(length);
+    for (let i = 0; i < length; i++) {
+        arr[i] = parseInt(hex.slice(i * 2, i * 2 + 2), 16);
+    }
+    return arr;
+}
+
+export function u8ArrayToBigInt(arr) {
+    let hex = '0x';
+    for (let i = 0; i < arr.length; i++) {
+        hex += arr[i].toString(16).padStart(2, '0');
+    }
+    return BigInt(hex);
+}

core/crypto/crypto.js

@@ -0,0 +1,90 @@
+import { AESECBCipher, AESEAXCipher } from "./aes.js";
+import { DESCBCCipher, DESECBCipher } from "./des.js";
+import { RSACipher } from "./rsa.js";
+import { DHCipher } from "./dh.js";
+import { MD5 } from "./md5.js";
+
+// A single interface for the cryptographic algorithms not supported by SubtleCrypto.
+// Both synchronous and asynchronous implmentations are allowed.
+class LegacyCrypto {
+    constructor() {
+        this._algorithms = {
+            "AES-ECB": AESECBCipher,
+            "AES-EAX": AESEAXCipher,
+            "DES-ECB": DESECBCipher,
+            "DES-CBC": DESCBCCipher,
+            "RSA-PKCS1-v1_5": RSACipher,
+            "DH": DHCipher,
+            "MD5": MD5,
+        };
+    }
+
+    encrypt(algorithm, key, data) {
+        if (key.algorithm.name !== algorithm.name) {
+            throw new Error("algorithm does not match");
+        }
+        if (typeof key.encrypt !== "function") {
+            throw new Error("key does not support encryption");
+        }
+        return key.encrypt(algorithm, data);
+    }
+
+    decrypt(algorithm, key, data) {
+        if (key.algorithm.name !== algorithm.name) {
+            throw new Error("algorithm does not match");
+        }
+        if (typeof key.decrypt !== "function") {
+            throw new Error("key does not support encryption");
+        }
+        return key.decrypt(algorithm, data);
+    }
+
+    importKey(format, keyData, algorithm, extractable, keyUsages) {
+        if (format !== "raw") {
+            throw new Error("key format is not supported");
+        }
+        const alg = this._algorithms[algorithm.name];
+        if (typeof alg === "undefined" || typeof alg.importKey !== "function") {
+            throw new Error("algorithm is not supported");
+        }
+        return alg.importKey(keyData, algorithm, extractable, keyUsages);
+    }
+
+    generateKey(algorithm, extractable, keyUsages) {
+        const alg = this._algorithms[algorithm.name];
+        if (typeof alg === "undefined" || typeof alg.generateKey !== "function") {
+            throw new Error("algorithm is not supported");
+        }
+        return alg.generateKey(algorithm, extractable, keyUsages);
+    }
+
+    exportKey(format, key) {
+        if (format !== "raw") {
+            throw new Error("key format is not supported");
+        }
+        if (typeof key.exportKey !== "function") {
+            throw new Error("key does not support exportKey");
+        }
+        return key.exportKey();
+    }
+
+    digest(algorithm, data) {
+        const alg = this._algorithms[algorithm];
+        if (typeof alg !== "function") {
+            throw new Error("algorithm is not supported");
+        }
+        return alg(data);
+    }
+
+    deriveBits(algorithm, key, length) {
+        if (key.algorithm.name !== algorithm.name) {
+            throw new Error("algorithm does not match");
+        }
+        if (typeof key.deriveBits !== "function") {
+            throw new Error("key does not support deriveBits");
+        }
+        return key.deriveBits(algorithm, length);
+    }
+}
+
+export default new LegacyCrypto;

core/des.js → core/crypto/des.js

@@ -128,7 +128,7 @@ const SP8 = [b|f,z|e,a|z,c|f,b|z,b|f,z|d,b|z,a|d,c|z,c|f,a|e,c|e,a|f,z|e,z|d,
 
 /* eslint-enable comma-spacing */
 
-export default class DES {
+class DES {
     constructor(password) {
         this.keys = [];
 
@@ -258,9 +258,73 @@ export default class DES {
         }
         return b;
     }
+}
+
+export class DESECBCipher {
+    constructor() {
+        this._cipher = null;
+    }
+
+    get algorithm() {
+        return { name: "DES-ECB" };
+    }
+
+    static importKey(key, _algorithm, _extractable, _keyUsages) {
+        const cipher = new DESECBCipher;
+        cipher._importKey(key);
+        return cipher;
+    }
 
-    // Encrypt 16 bytes of text using passwd as key
-    encrypt(t) {
-        return this.enc8(t.slice(0, 8)).concat(this.enc8(t.slice(8, 16)));
+    _importKey(key, _extractable, _keyUsages) {
+        this._cipher = new DES(key);
+    }
+
+    encrypt(_algorithm, plaintext) {
+        const x = new Uint8Array(plaintext);
+        if (x.length % 8 !== 0 || this._cipher === null) {
+            return null;
+        }
+        const n = x.length / 8;
+        for (let i = 0; i < n; i++) {
+            x.set(this._cipher.enc8(x.slice(i * 8, i * 8 + 8)), i * 8);
+        }
+        return x;
+    }
+}
+
+export class DESCBCCipher {
+    constructor() {
+        this._cipher = null;
+    }
+
+    get algorithm() {
+        return { name: "DES-CBC" };
+    }
+
+    static importKey(key, _algorithm, _extractable, _keyUsages) {
+        const cipher = new DESCBCCipher;
+        cipher._importKey(key);
+        return cipher;
+    }
+
+    _importKey(key) {
+        this._cipher = new DES(key);
+    }
+
+    encrypt(algorithm, plaintext) {
+        const x = new Uint8Array(plaintext);
+        let y = new Uint8Array(algorithm.iv);
+        if (x.length % 8 !== 0 || this._cipher === null) {
+            return null;
+        }
+        const n = x.length / 8;
+        for (let i = 0; i < n; i++) {
+            for (let j = 0; j < 8; j++) {
+                y[j] ^= plaintext[i * 8 + j];
+            }
+            y = this._cipher.enc8(y);
+            x.set(y, i * 8);
+        }
+        return x;
     }
 }