Remove table cipher.

Author: mrluanma

README.md

@@ -5,7 +5,7 @@ shadowsocks-heroku is a lightweight tunnel proxy which can help you get through
 
 shadowsocks-heroku uses WebSocket instead of raw sockets, so it can be deployed on [Heroku](https://www.heroku.com/).
 
-Notice that the protocol is INCOMPATIBLE with the origin shadowsocks.
+Notice that the protocol is INCOMPATIBLE with shadowsocks.
 
 Heroku
 ------
@@ -34,10 +34,10 @@ To [email protected]:still-tor-8707.git
 Set a few configs:
 
 ```
-$ heroku config:set METHOD=table KEY=foobar
+$ heroku config:set METHOD=aes-128-cfb KEY=foobar
 Setting config vars and restarting still-tor-8707... done, v11
 KEY:    foobar
-METHOD: table
+METHOD: aes-128-cfb
 ```
 
 Install project dependencies with `npm install`:
@@ -50,7 +50,7 @@ $ npm install
 Then run:
 
 ```
-$ node local.js -s still-tor-8707.herokuapp.com -l 1080 -m table -k foobar -r 80
+$ node local.js -s still-tor-8707.herokuapp.com -l 1080 -m aes-128-cfb -k foobar -r 80
 server listening at { address: '127.0.0.1', family: 'IPv4', port: 1080 }
 ```
 
@@ -71,16 +71,9 @@ $ heroku logs -t --app still-tor-8707
 Supported Ciphers
 -----------------
 
-- table
-- bf-cfb
-- des-cfb
-- rc2-cfb
-- idea-cfb
-- seed-cfb
-- cast5-cfb
 - aes-128-cfb
 - aes-192-cfb
 - aes-256-cfb
-- camellia-256-cfb
-- camellia-192-cfb
 - camellia-128-cfb
+- camellia-192-cfb
+- camellia-256-cfb

encrypt.js

@@ -1,55 +1,4 @@
 import crypto from 'crypto';
-const int32Max = Math.pow(2, 32);
-
-const cachedTables = {}; // password: [encryptTable, decryptTable]
-
-const getTable = function (key) {
-  if (cachedTables[key]) {
-    return cachedTables[key];
-  }
-  console.log('calculating ciphers');
-  let table = new Array(256);
-  const decrypt_table = new Array(256);
-  const md5sum = crypto.createHash('md5');
-  md5sum.update(key);
-  const hash = Buffer.from(md5sum.digest(), 'binary');
-  const al = hash.readUInt32LE(0);
-  const ah = hash.readUInt32LE(4);
-  let i = 0;
-
-  while (i < 256) {
-    table[i] = i;
-    i++;
-  }
-  i = 1;
-
-  while (i < 1024) {
-    table.sort(
-      (x, y) =>
-        (((ah % (x + i)) * int32Max + al) % (x + i)) -
-        (((ah % (y + i)) * int32Max + al) % (y + i)),
-    );
-    i++;
-  }
-  i = 0;
-  while (i < 256) {
-    decrypt_table[table[i]] = i;
-    ++i;
-  }
-  const result = [table, decrypt_table];
-  cachedTables[key] = result;
-  return result;
-};
-
-const substitute = function (table, buf) {
-  let i = 0;
-
-  while (i < buf.length) {
-    buf[i] = table[buf[i]];
-    i++;
-  }
-  return buf;
-};
 
 const bytes_to_key_results = {};
 
@@ -83,35 +32,22 @@ const method_supported = {
   'aes-128-cfb': [16, 16],
   'aes-192-cfb': [24, 16],
   'aes-256-cfb': [32, 16],
-  'bf-cfb': [16, 8],
   'camellia-128-cfb': [16, 16],
   'camellia-192-cfb': [24, 16],
   'camellia-256-cfb': [32, 16],
-  'cast5-cfb': [16, 8],
-  'des-cfb': [8, 8],
-  'idea-cfb': [16, 8],
-  'rc2-cfb': [16, 8],
-  'seed-cfb': [16, 16],
 };
 
-class Encryptor {
+export class Encryptor {
   constructor(key, method) {
     this.key = key;
     this.method = method;
     this.iv_sent = false;
-    if (this.method === 'table') {
-      this.method = null;
-    }
-    if (this.method) {
-      this.cipher = this.get_cipher(
-        this.key,
-        this.method,
-        1,
-        crypto.randomBytes(32),
-      );
-    } else {
-      [this.encryptTable, this.decryptTable] = getTable(this.key);
-    }
+    this.cipher = this.get_cipher(
+      this.key,
+      this.method,
+      1,
+      crypto.randomBytes(32),
+    );
   }
 
   get_cipher_len(method) {
@@ -141,36 +77,23 @@ class Encryptor {
   }
 
   encrypt(buf) {
-    if (this.method) {
-      const result = this.cipher.update(buf);
-      if (this.iv_sent) {
-        return result;
-      } else {
-        this.iv_sent = true;
-        return Buffer.concat([this.cipher_iv, result]);
-      }
+    const result = this.cipher.update(buf);
+    if (this.iv_sent) {
+      return result;
     } else {
-      return substitute(this.encryptTable, buf);
+      this.iv_sent = true;
+      return Buffer.concat([this.cipher_iv, result]);
     }
   }
 
   decrypt(buf) {
-    if (this.method) {
-      let result;
-      if (!this.decipher) {
-        const decipher_iv_len = this.get_cipher_len(this.method)[1];
-        const decipher_iv = buf.slice(0, decipher_iv_len);
-        this.decipher = this.get_cipher(this.key, this.method, 0, decipher_iv);
-        result = this.decipher.update(buf.slice(decipher_iv_len));
-        return result;
-      } else {
-        result = this.decipher.update(buf);
-        return result;
-      }
+    if (!this.decipher) {
+      const decipher_iv_len = this.get_cipher_len(this.method)[1];
+      const decipher_iv = buf.slice(0, decipher_iv_len);
+      this.decipher = this.get_cipher(this.key, this.method, 0, decipher_iv);
+      return this.decipher.update(buf.slice(decipher_iv_len));
     } else {
-      return substitute(this.decryptTable, buf);
+      return this.decipher.update(buf);
     }
   }
 }
-
-export {Encryptor, getTable};

local.js

@@ -58,11 +58,6 @@ const PORT = config.local_port;
 const KEY = config.password;
 let METHOD = config.method;
 const timeout = Math.floor(config.timeout * 1000);
-
-if (['', 'null', 'table'].includes(METHOD.toLowerCase())) {
-  METHOD = null;
-}
-
 const HTTPPROXY = process.env.http_proxy;
 
 if (HTTPPROXY) {

server.js

@@ -59,10 +59,6 @@ const KEY = config.password;
 let METHOD = config.method;
 const highWaterMark = +process.env.HIGH_WATER_MARK || 64 * 1024;
 
-if (['', 'null', 'table'].includes(METHOD.toLowerCase())) {
-  METHOD = null;
-}
-
 const server = http.createServer(function (req, res) {
   res.writeHead(200, {'Content-Type': 'text/plain'});
   res.end('asdf.');

test.js

@@ -1,54 +1,3 @@
-// test encryption
-import * as encrypt from './encrypt.js';
-
-const target = [
-  [
-    60, 53, 84, 138, 217, 94, 88, 23, 39, 242, 219, 35, 12, 157, 165, 181, 255,
-    143, 83, 247, 162, 16, 31, 209, 190, 171, 115, 65, 38, 41, 21, 245, 236, 46,
-    121, 62, 166, 233, 44, 154, 153, 145, 230, 49, 128, 216, 173, 29, 241, 119,
-    64, 229, 194, 103, 131, 110, 26, 197, 218, 59, 204, 56, 27, 34, 141, 221,
-    149, 239, 192, 195, 24, 155, 170, 183, 11, 254, 213, 37, 137, 226, 75, 203,
-    55, 19, 72, 248, 22, 129, 33, 175, 178, 10, 198, 71, 77, 36, 113, 167, 48,
-    2, 117, 140, 142, 66, 199, 232, 243, 32, 123, 54, 51, 82, 57, 177, 87, 251,
-    150, 196, 133, 5, 253, 130, 8, 184, 14, 152, 231, 3, 186, 159, 76, 89, 228,
-    205, 156, 96, 163, 146, 18, 91, 132, 85, 80, 109, 172, 176, 105, 13, 50,
-    235, 127, 0, 189, 95, 98, 136, 250, 200, 108, 179, 211, 214, 106, 168, 78,
-    79, 74, 210, 30, 73, 201, 151, 208, 114, 101, 174, 92, 52, 120, 240, 15,
-    169, 220, 182, 81, 224, 43, 185, 40, 99, 180, 17, 212, 158, 42, 90, 9, 191,
-    45, 6, 25, 4, 222, 67, 126, 1, 116, 124, 206, 69, 61, 7, 68, 97, 202, 63,
-    244, 20, 28, 58, 93, 134, 104, 144, 227, 147, 102, 118, 135, 148, 47, 238,
-    86, 112, 122, 70, 107, 215, 100, 139, 223, 225, 164, 237, 111, 125, 207,
-    160, 187, 246, 234, 161, 188, 193, 249, 252,
-  ],
-  [
-    151, 205, 99, 127, 201, 119, 199, 211, 122, 196, 91, 74, 12, 147, 124, 180,
-    21, 191, 138, 83, 217, 30, 86, 7, 70, 200, 56, 62, 218, 47, 168, 22, 107,
-    88, 63, 11, 95, 77, 28, 8, 188, 29, 194, 186, 38, 198, 33, 230, 98, 43, 148,
-    110, 177, 1, 109, 82, 61, 112, 219, 59, 0, 210, 35, 215, 50, 27, 103, 203,
-    212, 209, 235, 93, 84, 169, 166, 80, 130, 94, 164, 165, 142, 184, 111, 18,
-    2, 141, 232, 114, 6, 131, 195, 139, 176, 220, 5, 153, 135, 213, 154, 189,
-    238, 174, 226, 53, 222, 146, 162, 236, 158, 143, 55, 244, 233, 96, 173, 26,
-    206, 100, 227, 49, 178, 34, 234, 108, 207, 245, 204, 150, 44, 87, 121, 54,
-    140, 118, 221, 228, 155, 78, 3, 239, 101, 64, 102, 17, 223, 41, 137, 225,
-    229, 66, 116, 171, 125, 40, 39, 71, 134, 13, 193, 129, 247, 251, 20, 136,
-    242, 14, 36, 97, 163, 181, 72, 25, 144, 46, 175, 89, 145, 113, 90, 159, 190,
-    15, 183, 73, 123, 187, 128, 248, 252, 152, 24, 197, 68, 253, 52, 69, 117,
-    57, 92, 104, 157, 170, 214, 81, 60, 133, 208, 246, 172, 23, 167, 160, 192,
-    76, 161, 237, 45, 4, 58, 10, 182, 65, 202, 240, 185, 241, 79, 224, 132, 51,
-    42, 126, 105, 37, 250, 149, 32, 243, 231, 67, 179, 48, 9, 106, 216, 31, 249,
-    19, 85, 254, 156, 115, 255, 120, 75, 16,
-  ],
-];
-const tables = encrypt.getTable('foobar!');
-console.log(JSON.stringify(tables));
-let i = 0;
-
-while (i < 256) {
-  console.assert(tables[0][i] === target[0][i]);
-  console.assert(tables[1][i] === target[1][i]);
-  i++;
-}
-
 // test proxy
 
 import child_process from 'child_process';