From 0ba76b666d804436dd8383815f2221309cad2590 Mon Sep 17 00:00:00 2001
From: BreakWa11 <mmgac001@gmail.com>
Date: Thu, 22 Oct 2015 15:55:38 +0800
Subject: [PATCH] not redirect host to chn web add auth_simple

---
 shadowsocks/obfsplugin/verify_simple.py | 217 +++++++++++++++++++++++-
 shadowsocks/tcprelay.py                 |   2 +-
 2 files changed, 216 insertions(+), 3 deletions(-)

diff --git a/shadowsocks/obfsplugin/verify_simple.py b/shadowsocks/obfsplugin/verify_simple.py
index 10ba8f7..fde73fa 100644
--- a/shadowsocks/obfsplugin/verify_simple.py
+++ b/shadowsocks/obfsplugin/verify_simple.py
@@ -23,7 +23,9 @@ import hashlib
 import logging
 import binascii
 import base64
+import time
 import datetime
+import random
 import struct
 import zlib
 
@@ -38,9 +40,13 @@ def create_verify_obfs(method):
 def create_verify_deflate(method):
     return verify_deflate(method)
 
+def create_auth_obfs(method):
+    return auth_simple(method)
+
 obfs_map = {
         'verify_simple': (create_verify_obfs,),
         'verify_deflate': (create_verify_deflate,),
+        'auth_simple': (create_auth_obfs,),
 }
 
 def match_begin(str1, str2):
@@ -49,7 +55,7 @@ def match_begin(str1, str2):
             return True
     return False
 
-class sub_encode_obfs(object):
+class obfs_verify_data(object):
     def __init__(self):
         self.sub_obfs = None
 
@@ -60,7 +66,7 @@ class verify_base(plain.plain):
         self.sub_obfs = None
 
     def init_data(self):
-        return sub_encode_obfs()
+        return obfs_verify_data()
 
     def set_server_info(self, server_info):
         try:
@@ -283,3 +289,210 @@ class verify_deflate(verify_base):
             self.decrypt_packet_num += 1
         return out_buf
 
+class client_queue(object):
+    def __init__(self, begin_id):
+        self.front = begin_id
+        self.back = begin_id
+        self.alloc = {}
+        self.enable = True
+        self.last_update = time.time()
+
+    def update(self):
+        self.last_update = time.time()
+
+    def is_active(self):
+        return time.time() - self.last_update < 60 * 3
+
+    def re_enable(self, connection_id):
+        self.enable = True
+        self.alloc = {}
+        self.front = connection_id
+        self.back = connection_id
+
+    def insert(self, connection_id):
+        self.update()
+        if not self.enable:
+            return False
+        if connection_id < self.front:
+            return False
+        if not self.is_active():
+            self.re_enable(connection_id)
+        if connection_id > self.front + 0x4000:
+            return False
+        if connection_id in self.alloc:
+            return False
+        if self.back <= connection_id:
+            self.back = connection_id + 1
+        self.alloc[connection_id] = 1
+        while (self.front in self.alloc) or self.front + 0x1000 < self.back:
+            if self.front in self.alloc:
+                del self.alloc[self.front]
+            self.front += 1
+        return True
+
+class obfs_auth_data(object):
+    def __init__(self):
+        self.sub_obfs = None
+        self.client_id = {}
+
+    def update(self, client_id, connection_id):
+        if client_id in self.client_id:
+            self.client_id[client_id].update()
+
+    def insert(self, client_id, connection_id):
+        max_client = 16
+        if client_id not in self.client_id or not self.client_id[client_id].enable:
+            active = 0
+            for c_id in self.client_id:
+                if self.client_id[c_id].is_active():
+                    active += 1
+            if active >= max_client:
+                return False
+
+            if len(self.client_id) < max_client:
+                if client_id not in self.client_id:
+                    self.client_id[client_id] = client_queue(connection_id)
+                else:
+                    self.client_id[client_id].re_enable(connection_id)
+                return self.client_id[client_id].insert(connection_id)
+            keys = self.client_id.keys()
+            random.shuffle(keys)
+            for c_id in keys:
+                if not self.client_id[c_id].is_active() and self.client_id[c_id].enable:
+                    if len(self.client_id) >= 256:
+                        del self.client_id[c_id]
+                    else:
+                        self.client_id[c_id].enable = False
+                    if client_id not in self.client_id:
+                        self.client_id[client_id] = client_queue(connection_id)
+                    else:
+                        self.client_id[client_id].re_enable(connection_id)
+                    return self.client_id[client_id].insert(connection_id)
+            return False
+        else:
+            return self.client_id[client_id].insert(connection_id)
+
+class auth_simple(verify_base):
+    def __init__(self, method):
+        super(auth_simple, self).__init__(method)
+        self.recv_buf = b''
+        self.unit_len = 8100
+        self.decrypt_packet_num = 0
+        self.raw_trans = False
+        self.has_sent_header = False
+        self.has_recv_header = False
+        self.client_id = 0
+        self.connection_id = 0
+
+    def init_data(self):
+        return obfs_auth_data()
+
+    def pack_data(self, buf):
+        if len(buf) == 0:
+            return b''
+        rnd_data = os.urandom(common.ord(os.urandom(1)[0]) % 16)
+        data = common.chr(len(rnd_data) + 1) + rnd_data + buf
+        data = struct.pack('>H', len(data) + 6) + data
+        crc = (0xffffffff - binascii.crc32(data)) & 0xffffffff
+        data += struct.pack('<I', crc)
+        return data
+
+    def client_pre_encrypt(self, buf):
+        ret = b''
+        while len(buf) > self.unit_len:
+            ret += self.pack_data(buf[:self.unit_len])
+            buf = buf[self.unit_len:]
+        ret += self.pack_data(buf)
+        return ret
+
+    def client_post_decrypt(self, buf):
+        if self.raw_trans:
+            return buf
+        self.recv_buf += buf
+        out_buf = b''
+        while len(self.recv_buf) > 2:
+            length = struct.unpack('>H', self.recv_buf[:2])[0]
+            if length >= 8192:
+                self.raw_trans = True
+                self.recv_buf = b''
+                if self.decrypt_packet_num == 0:
+                    return None
+                else:
+                    raise Exception('server_post_decrype data error')
+            if length > len(self.recv_buf):
+                break
+
+            if (binascii.crc32(self.recv_buf[:length]) & 0xffffffff) != 0xffffffff:
+                self.raw_trans = True
+                self.recv_buf = b''
+                if self.decrypt_packet_num == 0:
+                    return None
+                else:
+                    raise Exception('server_post_decrype data uncorrect CRC32')
+
+            pos = common.ord(self.recv_buf[2]) + 2
+            out_buf += self.recv_buf[pos:length - 4]
+            self.recv_buf = self.recv_buf[length:]
+
+        if out_buf:
+            self.decrypt_packet_num += 1
+        return out_buf
+
+    def server_pre_encrypt(self, buf):
+        ret = b''
+        while len(buf) > self.unit_len:
+            ret += self.pack_data(buf[:self.unit_len])
+            buf = buf[self.unit_len:]
+        ret += self.pack_data(buf)
+        return ret
+
+    def server_post_decrypt(self, buf):
+        if self.raw_trans:
+            return buf
+        self.recv_buf += buf
+        out_buf = b''
+        while len(self.recv_buf) > 2:
+            length = struct.unpack('>H', self.recv_buf[:2])[0]
+            if length >= 8192:
+                self.raw_trans = True
+                self.recv_buf = b''
+                if self.decrypt_packet_num == 0:
+                    return b'E'
+                else:
+                    raise Exception('server_post_decrype data error')
+            if length > len(self.recv_buf):
+                break
+
+            if (binascii.crc32(self.recv_buf[:length]) & 0xffffffff) != 0xffffffff:
+                self.raw_trans = True
+                self.recv_buf = b''
+                if self.decrypt_packet_num == 0:
+                    return b'E'
+                else:
+                    raise Exception('server_post_decrype data uncorrect CRC32')
+
+            pos = common.ord(self.recv_buf[2]) + 2
+            out_buf += self.recv_buf[pos:length - 4]
+            if not self.has_recv_header:
+                if len(out_buf) < 8:
+                    self.raw_trans = True
+                    self.recv_buf = b''
+                    return b'E'
+                client_id = struct.unpack('<I', out_buf[:4])[0]
+                connection_id = struct.unpack('<I', out_buf[4:8])[0]
+                if self.server_info.data.insert(client_id, connection_id):
+                    self.has_recv_header = True
+                    out_buf = out_buf[8:]
+                    self.client_id = client_id
+                    self.connection_id = connection_id
+                else:
+                    self.raw_trans = True
+                    self.recv_buf = b''
+                    return b'E'
+            self.recv_buf = self.recv_buf[length:]
+
+        if out_buf:
+            self.server_info.data.update(self.client_id, self.connection_id)
+            self.decrypt_packet_num += 1
+        return out_buf
+
diff --git a/shadowsocks/tcprelay.py b/shadowsocks/tcprelay.py
index a51830a..5d1f251 100644
--- a/shadowsocks/tcprelay.py
+++ b/shadowsocks/tcprelay.py
@@ -307,7 +307,7 @@ class TCPRelayHandler(object):
 
     def _get_redirect_host(self, client_address, ogn_data):
         # test
-        host_list = [(b"www.bing.com", 80), (b"www.microsoft.com", 80), (b"www.baidu.com", 443), (b"www.qq.com", 80), (b"www.csdn.net", 80), (b"1.2.3.4", 1000)]
+        host_list = [(b"www.bing.com", 80), (b"www.microsoft.com", 80), (b"cloudfront.com", 80), (b"cloudflare.com", 80), (b"1.2.3.4", 1000), (b"0.0.0.0", 0)]
         hash_code = binascii.crc32(ogn_data)
         addrs = socket.getaddrinfo(client_address[0], client_address[1], 0, socket.SOCK_STREAM, socket.SOL_TCP)
         af, socktype, proto, canonname, sa = addrs[0]