updating socks version to support squid proxy

Author: Claudio

socks.py

@@ -43,10 +43,12 @@
 import socket
 import struct
 import sys
+import logging
 
 PROXY_TYPE_SOCKS4 = 1
 PROXY_TYPE_SOCKS5 = 2
 PROXY_TYPE_HTTP = 3
+PROXY_TYPE_HTTP_NO_TUNNEL = 4
 
 _defaultproxy = None
 _orgsocket = socket.socket
@@ -123,6 +125,7 @@ def __init__(self, family=socket.AF_INET, type=socket.SOCK_STREAM, proto=0, _soc
             self.__proxy = (None, None, None, None, None, None)
         self.__proxysockname = None
         self.__proxypeername = None
+        self.__httptunnel = True
 
     def __recvall(self, count):
         """__recvall(count) -> data
@@ -136,6 +139,34 @@ def __recvall(self, count):
             data = data + d
         return data
 
+    def sendall(self, bytes):
+        if 'encode' in dir(bytes):
+            bytes = bytes.encode()
+        if not self.__httptunnel:
+            bytes = self.__rewriteproxy(bytes)
+        socket.socket.sendall(self, bytes)
+
+    def __rewriteproxy(self, header):
+        """ rewrite HTTP request headers to support non-tunneling proxies 
+        (i.e. thos which do not support the CONNECT method).
+        This only works for HTTP (not HTTPS) since HTTPS requires tunneling.
+        """
+        host, endpt = None, None
+        hdrs = header.split("\r\n")
+        for hdr in hdrs:
+            if hdr.lower().startswith("host:"):
+                host = hdr
+            elif hdr.lower().startswith("get") or hdr.lower().startswith("post"):
+                endpt = hdr
+        if host and endpt: 
+            hdrs.remove(host)
+            hdrs.remove(endpt)
+            host = host.split(" ")[1]
+            endpt = endpt.split(" ")
+            hdrs.insert(0, "%s http://%s%s %s" % (endpt[0], host, endpt[1], endpt[2]))
+        return "\r\n".join(hdrs)
+
+
     def setproxy(self, proxytype=None, addr=None, port=None, rdns=True, username=None, password=None):
         """setproxy(proxytype, addr[, port[, rdns[, username[, password]]]])
         Sets the proxy to be used.
@@ -376,6 +407,17 @@ def connect(self, destpair):
                 portnum = 8080
             _orgsocket.connect(self,(self.__proxy[1], portnum))
             self.__negotiatehttp(destpair[0], destpair[1])
+        elif self.__proxy[0] == PROXY_TYPE_HTTP_NO_TUNNEL:
+            if self.__proxy[2] != None:
+                portnum = self.__proxy[2]
+            else:
+                portnum = 8080
+            _orgsocket.connect(self,(self.__proxy[1],portnum))
+            if 443 == destpair[1]:
+                logging.warn("SSL connections (generally on port 443) require the use of tunneling - failing back to PROXY_TYPE_HTTP")
+                self.__negotiatehttp(destpair[0],destpair[1])
+            else:
+                self.httptunnel = False
         elif self.__proxy[0] == None:
             _orgsocket.connect(self, (destpair[0], destpair[1]))
         else: