Patch #401196: Use getaddrinfo and AF_INET6 in TCP servers and clients.

1 files changed, 90 insertions, 22 deletions

diff --git a/Lib/ftplib.py b/Lib/ftplib.py
index 3263281..693d5a9 100644
--- a/Lib/ftplib.py
+++ b/Lib/ftplib.py
@@ -108,17 +108,29 @@ class FTP:
             self.connect(host)
             if user: self.login(user, passwd, acct)
 
-    def connect(self, host='', port=0):
-        '''Connect to host.  Arguments are:
-        - host: hostname to connect to (string, default previous host)
-        - port: port to connect to (integer, default previous port)'''
-        if host: self.host = host
-        if port: self.port = port
-        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        self.sock.connect((self.host, self.port))
-        self.file = self.sock.makefile('rb')
-        self.welcome = self.getresp()
-        return self.welcome
+    def connect(self, host = '', port = 0):
+	'''Connect to host.  Arguments are:
+	- host: hostname to connect to (string, default previous host)
+	- port: port to connect to (integer, default previous port)'''
+	if host: self.host = host
+	if port: self.port = port
+	self.passiveserver = 0
+	for res in socket.getaddrinfo(self.host, self.port, 0, socket.SOCK_STREAM):
+	    af, socktype, proto, canonname, sa = res
+	    try:
+		self.sock = socket.socket(af, socktype, proto)
+		self.sock.connect(sa)
+	    except socket.error, msg:
+		self.sock.close()
+		self.sock = None
+		continue
+	    break
+	if not self.sock:
+	    raise socket.error, msg
+	self.af = af
+	self.file = self.sock.makefile('rb')
+	self.welcome = self.getresp()
+	return self.welcome
 
     def getwelcome(self):
         '''Get the welcome message from the server.
@@ -243,15 +255,48 @@ class FTP:
         cmd = 'PORT ' + ','.join(bytes)
         return self.voidcmd(cmd)
 
+    def sendeprt(self, host, port):
+	'''Send a EPRT command with the current host and the given port number.'''
+	af = 0
+	if self.af == socket.AF_INET:
+	    af = 1
+	if self.af == socket.AF_INET6:
+	    af = 2
+	if af == 0:
+	    raise error_proto, 'unsupported address family'
+	fields = ['', `af`, host, `port`, '']
+	cmd = 'EPRT ' + string.joinfields(fields, '|')
+	return self.voidcmd(cmd)
+
     def makeport(self):
-        '''Create a new socket and send a PORT command for it.'''
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        sock.bind(('', 0))
-        sock.listen(1)
-        dummyhost, port = sock.getsockname() # Get proper port
-        host, dummyport = self.sock.getsockname() # Get proper host
-        resp = self.sendport(host, port)
-        return sock
+	'''Create a new socket and send a PORT command for it.'''
+	for res in socket.getaddrinfo(None, 0, self.af, socket.SOCK_STREAM, 0, socket.AI_PASSIVE):
+	    af, socktype, proto, canonname, sa = res
+	    try:
+		sock = socket.socket(af, socktype, proto)
+		sock.bind(sa)
+	    except socket.error, msg:
+		sock.close()
+		sock = None
+		continue
+	    break
+	if not sock:
+	    raise socket.error, msg
+	sock.listen(1)
+	port = sock.getsockname()[1] # Get proper port
+	host = self.sock.getsockname()[0] # Get proper host
+	if self.af == socket.AF_INET:
+	    resp = self.sendport(host, port)
+	else:
+	    resp = self.sendeprt(host, port)
+	return sock
+
+    def makepasv(self):
+	if self.af == socket.AF_INET:
+	    host, port = parse227(self.sendcmd('PASV'))
+	else:
+	    host, port = parse229(self.sendcmd('EPSV'), self.sock.getpeername())
+	return host, port
 
     def ntransfercmd(self, cmd, rest=None):
         """Initiate a transfer over the data connection.
@@ -270,9 +315,10 @@ class FTP:
         """
         size = None
         if self.passiveserver:
-            host, port = parse227(self.sendcmd('PASV'))
-            conn=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-            conn.connect((host, port))
+            host, port = self.makepasv()
+	    af, socktype, proto, canon, sa = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM)[0]
+	    conn = socket.socket(af, socktype, proto)
+	    conn.connect(sa)
             if rest is not None:
                 self.sendcmd("REST %s" % rest)
             resp = self.sendcmd(cmd)
@@ -523,6 +569,28 @@ def parse227(resp):
     return host, port
 
 
+def parse229(resp, peer):
+    '''Parse the '229' response for a EPSV request.
+    Raises error_proto if it does not contain '(|||port|)'
+    Return ('host.addr.as.numbers', port#) tuple.'''
+
+    if resp[:3] <> '229':
+	raise error_reply, resp
+    left = string.find(resp, '(')
+    if left < 0: raise error_proto, resp
+    right = string.find(resp, ')', left + 1)
+    if right < 0:
+	raise error_proto, resp	# should contain '(|||port|)'
+    if resp[left + 1] <> resp[right - 1]:
+	raise error_proto, resp
+    parts = string.split(resp[left + 1:right], resp[left+1])
+    if len(parts) <> 5:
+	raise error_proto, resp
+    host = peer[0]
+    port = string.atoi(parts[3])
+    return host, port
+
+
 def parse257(resp):
     '''Parse the '257' response for a MKD or PWD request.
     This is a response to a MKD or PWD request: a directory name.