diff options
Diffstat (limited to 'proxies/proxy_socks4/proxy_socks4.go')
| -rw-r--r-- | proxies/proxy_socks4/proxy_socks4.go | 164 |
1 files changed, 0 insertions, 164 deletions
diff --git a/proxies/proxy_socks4/proxy_socks4.go b/proxies/proxy_socks4/proxy_socks4.go deleted file mode 100644 index 4e67f46..0000000 --- a/proxies/proxy_socks4/proxy_socks4.go +++ /dev/null @@ -1,164 +0,0 @@ -/* - * Copyright (c) 2014, Yawning Angel <yawning at torproject dot org> - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are met: - * - * * Redistributions of source code must retain the above copyright notice, - * this list of conditions and the following disclaimer. - * - * * Redistributions in binary form must reproduce the above copyright notice, - * this list of conditions and the following disclaimer in the documentation - * and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" - * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE - * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR - * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF - * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS - * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN - * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGE. - * - * This is inspired by go.net/proxy/socks5.go: - * - * Copyright 2011 The Go Authors. All rights reserved. - * Use of this source code is governed by a BSD-style - * license that can be found in the LICENSE file. - */ - -package proxy_socks4 - -import ( - "errors" - "fmt" - "io" - "net" - "net/url" - "strconv" - - "golang.org/x/net/proxy" -) - -// socks4Proxy is a SOCKS4 proxy. -type socks4Proxy struct { - hostPort string - username string - forward proxy.Dialer -} - -const ( - socks4Version = 0x04 - socks4CommandConnect = 0x01 - socks4Null = 0x00 - socks4ReplyVersion = 0x00 - - socks4Granted = 0x5a - socks4Rejected = 0x5b - socks4RejectedIdentdFailed = 0x5c - socks4RejectedIdentdMismatch = 0x5d -) - -func newSOCKS4(uri *url.URL, forward proxy.Dialer) (proxy.Dialer, error) { - s := new(socks4Proxy) - s.hostPort = uri.Host - s.forward = forward - if uri.User != nil { - s.username = uri.User.Username() - } - return s, nil -} - -func (s *socks4Proxy) Dial(network, addr string) (net.Conn, error) { - if network != "tcp" && network != "tcp4" { - return nil, errors.New("invalid network type") - } - - // Deal with the destination address/string. - ipStr, portStr, err := net.SplitHostPort(addr) - if err != nil { - return nil, err - } - ip := net.ParseIP(ipStr) - if ip == nil { - return nil, errors.New("failed to parse destination IP") - } - ip4 := ip.To4() - if ip4 == nil { - return nil, errors.New("destination address is not IPv4") - } - port, err := strconv.ParseUint(portStr, 10, 16) - if err != nil { - return nil, err - } - - // Connect to the proxy. - c, err := s.forward.Dial("tcp", s.hostPort) - if err != nil { - return nil, err - } - - // Make/write the request: - // +----+----+----+----+----+----+----+----+----+----+....+----+ - // | VN | CD | DSTPORT | DSTIP | USERID |NULL| - // +----+----+----+----+----+----+----+----+----+----+....+----+ - - req := make([]byte, 0, 9+len(s.username)) - req = append(req, socks4Version) - req = append(req, socks4CommandConnect) - req = append(req, byte(port>>8), byte(port)) - req = append(req, ip4...) - if s.username != "" { - req = append(req, s.username...) - } - req = append(req, socks4Null) - _, err = c.Write(req) - if err != nil { - c.Close() - return nil, err - } - - // Read the response: - // +----+----+----+----+----+----+----+----+ - // | VN | CD | DSTPORT | DSTIP | - // +----+----+----+----+----+----+----+----+ - - var resp [8]byte - _, err = io.ReadFull(c, resp[:]) - if err != nil { - c.Close() - return nil, err - } - if resp[0] != socks4ReplyVersion { - c.Close() - return nil, errors.New("proxy returned invalid SOCKS4 version") - } - if resp[1] != socks4Granted { - c.Close() - return nil, fmt.Errorf("proxy error: %s", socks4ErrorToString(resp[1])) - } - - return c, nil -} - -func socks4ErrorToString(code byte) string { - switch code { - case socks4Rejected: - return "request rejected or failed" - case socks4RejectedIdentdFailed: - return "request rejected becasue SOCKS server cannot connect to identd on the client" - case socks4RejectedIdentdMismatch: - return "request rejected because the client program and identd report different user-ids" - default: - return fmt.Sprintf("unknown failure code %x", code) - } -} - -func init() { - // Despite the scheme name, this really is SOCKS4. - proxy.RegisterDialerType("socks4a", newSOCKS4) -} |