1 /* Copyright (c) 2001 Matej Pfajfar.
2  * Copyright (c) 2001-2004, Roger Dingledine.
3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
4  * Copyright (c) 2007-2021, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
6 
7 /**
8  * @file socks_request_st.h
9  * @brief Client request structure.
10  **/
11 
12 #ifndef SOCKS_REQUEST_ST_H
13 #define SOCKS_REQUEST_ST_H
14 
15 #include "lib/net/socks5_status.h"
16 
17 #define MAX_SOCKS_REPLY_LEN 1024
18 
19 #define SOCKS_NO_AUTH 0x00
20 #define SOCKS_USER_PASS 0x02
21 
22 /** Please open a TCP connection to this addr:port. */
23 #define SOCKS_COMMAND_CONNECT       0x01
24 /** Please turn this FQDN into an IP address, privately. */
25 #define SOCKS_COMMAND_RESOLVE       0xF0
26 /** Please turn this IP address into an FQDN, privately. */
27 #define SOCKS_COMMAND_RESOLVE_PTR   0xF1
28 
29 /* || 0 is for -Wparentheses-equality (-Wall?) appeasement under clang */
30 #define SOCKS_COMMAND_IS_CONNECT(c) (((c)==SOCKS_COMMAND_CONNECT) || 0)
31 #define SOCKS_COMMAND_IS_RESOLVE(c) ((c)==SOCKS_COMMAND_RESOLVE || \
32                                      (c)==SOCKS_COMMAND_RESOLVE_PTR)
33 
34 /** State of a SOCKS request from a user to an OP.  Also used to encode other
35  * information for non-socks user request (such as those on TransPort and
36  * DNSPort) */
37 struct socks_request_t {
38   /** Which version of SOCKS did the client use? One of "0, 4, 5" -- where
39    * 0 means that no socks handshake ever took place, and this is just a
40    * stub connection (e.g. see connection_ap_make_link()). */
41   uint8_t socks_version;
42   /** If using socks5 authentication, which authentication type did we
43    * negotiate?  currently we support 0 (no authentication) and 2
44    * (username/password). */
45   uint8_t auth_type;
46   /** What is this stream's goal? One of the SOCKS_COMMAND_* values */
47   uint8_t command;
48   /** Which kind of listener created this stream? */
49   uint8_t listener_type;
50   size_t replylen; /**< Length of <b>reply</b>. */
51   uint8_t reply[MAX_SOCKS_REPLY_LEN]; /**< Write an entry into this string if
52                                     * we want to specify our own socks reply,
53                                     * rather than using the default socks4 or
54                                     * socks5 socks reply. We use this for the
55                                     * two-stage socks5 handshake.
56                                     */
57   char address[MAX_SOCKS_ADDR_LEN]; /**< What address did the client ask to
58                                        connect to/resolve? */
59   uint16_t port; /**< What port did the client ask to connect to? */
60   unsigned int has_finished : 1; /**< Has the SOCKS handshake finished? Used to
61                               * make sure we send back a socks reply for
62                               * every connection. */
63   unsigned int got_auth : 1; /**< Have we received any authentication data? */
64   /** If this is set, we will choose "no authentication" instead of
65    * "username/password" authentication if both are offered. Used as input to
66    * parse_socks. */
67   unsigned int socks_prefer_no_auth : 1;
68   /** If set, we can send back the extended error code in the reply. */
69   unsigned int socks_use_extended_errors : 1;
70   /** If non zero, this contains the extended error code that should be used
71    * if the port was configured to use them. */
72   socks5_reply_status_t socks_extended_error_code;
73 
74   /** Number of bytes in username; 0 if username is NULL */
75   size_t usernamelen;
76   /** Number of bytes in password; 0 if password is NULL */
77   uint8_t passwordlen;
78   /** The negotiated username value if any (for socks5), or the entire
79    * authentication string (for socks4).  This value is NOT nul-terminated;
80    * see usernamelen for its length. */
81   char *username;
82   /** The negotiated password value if any (for socks5). This value is NOT
83    * nul-terminated; see passwordlen for its length. */
84   char *password;
85 
86   uint8_t socks5_atyp; /* SOCKS5 address type */
87 };
88 
89 #endif /* !defined(SOCKS_REQUEST_ST_H) */
90