r8894@Kushana: nickm | 2006-09-21 18:30:42 -0400

 Specify and implement SOCKS5 interface for reverse hostname lookup.


svn:r8451

1 files changed, 44 insertions, 21 deletions

diff --git a/contrib/tor-resolve.py b/contrib/tor-resolve.py
index dd44255bc1..3557c2aa96 100755
--- a/contrib/tor-resolve.py
+++ b/contrib/tor-resolve.py
@@ -32,15 +32,14 @@ def socks5Hello():
 def socks5ParseHello(response):
     if response != "\x05\x00":
         raise ValueError("Bizarre socks5 response")
-def socks5ResolveRequest(hostname):
+def socks5ResolveRequest(hostname, atype=0x03, command=0xF0):
     version = 5
-    command = 0xF0
     rsv = 0
     port = 0
-    atype = 0x03
     reqheader = struct.pack("!BBBBB",version, command, rsv, atype, len(hostname))
     portstr = struct.pack("!H",port)
     return "%s%s%s"%(reqheader,hostname,portstr)
+
 def socks5ParseResponse(r):
     if len(r)<8:
         return None
@@ -49,18 +48,27 @@ def socks5ParseResponse(r):
     assert rsv==0
     if reply != 0x00:
         return "ERROR",reply
-    assert atype in (0x01,0x04)
-    expected_len = 4 + ({1:4,4:16}[atype]) + 2
-    if len(r) < expected_len:
-        return None
-    elif len(r) > expected_len:
-        raise ValueError("Overlong socks5 reply!")
-    addr = r[4:-2]
-    if atype == 0x01:
-        return "%d.%d.%d.%d"%tuple(map(ord,addr))
+    assert atype in (0x01,0x03,0x04)
+    if atype != 0x03:
+        expected_len = 4 + ({1:4,4:16}[atype]) + 2
+        if len(r) < expected_len:
+            return None
+        elif len(r) > expected_len:
+            raise ValueError("Overlong socks5 reply!")
+        addr = r[4:-2]
+        if atype == 0x01:
+            return "%d.%d.%d.%d"%tuple(map(ord,addr))
+        else:
+            # not really the right way to format IPv6
+            return "IPv6: %s"%(":".join([hex(ord(c)) for c in addr]))
     else:
-        # not really the right way to format IPv6
-        return "IPv6: %s"%(":".join([hex(ord(c)) for c in addr]))
+        nul = r.index('\0',4)
+        return r[4:nul]
+
+def socks5ResolvePTRRequest(hostname):
+    return socks5ResolveRequest(socket.inet_aton(hostname),
+                                atype=1, command = 0xF1)
+
 
 def parseHostAndPort(h):
     host, port = "localhost", 9050
@@ -80,14 +88,18 @@ def parseHostAndPort(h):
 
     return host, port
 
-def resolve(hostname, sockshost, socksport, socksver=4):
+def resolve(hostname, sockshost, socksport, socksver=4, reverse=0):
     assert socksver in (4,5)
     if socksver == 4:
         fmt = socks4AResolveRequest
         parse = socks4AParseResponse
-    else:
+    elif not reverse:
         fmt = socks5ResolveRequest
         parse = socks5ParseResponse
+    else:
+        fmt = socks5ResolvePTRRequest
+        parse = socks5ParseResponse
+
     s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
     s.connect((sockshost,socksport))
     if socksver == 5:
@@ -114,14 +126,25 @@ if __name__ == '__main__':
         print "Syntax: resolve.py [-4|-5] hostname [sockshost:socksport]"
         sys.exit(0)
     socksver = 4
-    if sys.argv[1] in ("-4", "-5"):
-        socksver = int(sys.argv[1][1])
-        del sys.argv[1]
-    if len(sys.argv) == 4:
+    reverse = 0
+    while sys.argv[1] == '-':
+        if sys.argv[1] in ("-4", "-5"):
+            socksver = int(sys.argv[1][1])
+            del sys.argv[1]
+        elif sys.argv[1] == '-x':
+            reverse = 1
+            del sys.argv[1]
+        elif sys.argv[1] == '--':
+            break
+
+    if len(sys.argv) >= 4:
         print "Syntax: resolve.py [-4|-5] hostname [sockshost:socksport]"
         sys.exit(0)
     if len(sys.argv) == 3:
         sh,sp = parseHostAndPort(sys.argv[2])
     else:
         sh,sp = parseHostAndPort("")
-    resolve(sys.argv[1], sh, sp, socksver)
+
+    if reverse and socksver == 4:
+        socksver = 5
+    resolve(sys.argv[1], sh, sp, socksver, reverse)