2 * Network proxy abstraction in PuTTY
4 * A proxy layer, if necessary, wedges itself between the network
5 * code and the higher level backend.
10 #define DEFINE_PLUG_METHOD_MACROS
16 * Call this when proxy negotiation is complete, so that this
17 * socket can begin working normally.
19 void proxy_activate (Proxy_Socket p)
24 p->state = PROXY_STATE_ACTIVE;
26 /* let's try to keep extra receive events from coming through */
27 sk_set_frozen(p->sub_socket, 1);
29 /* send buffered OOB writes */
30 while (bufchain_size(&p->pending_oob_output_data) > 0) {
31 bufchain_prefix(&p->pending_oob_output_data, &data, &len);
32 sk_write_oob(p->sub_socket, data, len);
33 bufchain_consume(&p->pending_oob_output_data, len);
35 bufchain_clear(&p->pending_oob_output_data);
37 /* send buffered normal writes */
38 while (bufchain_size(&p->pending_output_data) > 0) {
39 bufchain_prefix(&p->pending_output_data, &data, &len);
40 sk_write(p->sub_socket, data, len);
41 bufchain_consume(&p->pending_output_data, len);
43 bufchain_clear(&p->pending_output_data);
45 /* if we were asked to flush the output during
46 * the proxy negotiation process, do so now.
48 if (p->pending_flush) sk_flush(p->sub_socket);
50 /* forward buffered recv data to the backend */
51 while (bufchain_size(&p->pending_input_data) > 0) {
52 bufchain_prefix(&p->pending_input_data, &data, &len);
53 plug_receive(p->plug, 0, data, len);
54 bufchain_consume(&p->pending_input_data, len);
56 bufchain_clear(&p->pending_input_data);
58 /* now set the underlying socket to whatever freeze state they wanted */
59 sk_set_frozen(p->sub_socket, p->freeze);
62 /* basic proxy socket functions */
64 static Plug sk_proxy_plug (Socket s, Plug p)
66 Proxy_Socket ps = (Proxy_Socket) s;
73 static void sk_proxy_close (Socket s)
75 Proxy_Socket ps = (Proxy_Socket) s;
77 sk_close(ps->sub_socket);
81 static int sk_proxy_write (Socket s, char *data, int len)
83 Proxy_Socket ps = (Proxy_Socket) s;
85 if (ps->state != PROXY_STATE_ACTIVE) {
86 bufchain_add(&ps->pending_output_data, data, len);
87 return bufchain_size(&ps->pending_output_data);
89 return sk_write(ps->sub_socket, data, len);
92 static int sk_proxy_write_oob (Socket s, char *data, int len)
94 Proxy_Socket ps = (Proxy_Socket) s;
96 if (ps->state != PROXY_STATE_ACTIVE) {
97 bufchain_clear(&ps->pending_output_data);
98 bufchain_clear(&ps->pending_oob_output_data);
99 bufchain_add(&ps->pending_oob_output_data, data, len);
102 return sk_write_oob(ps->sub_socket, data, len);
105 static void sk_proxy_flush (Socket s)
107 Proxy_Socket ps = (Proxy_Socket) s;
109 if (ps->state != PROXY_STATE_ACTIVE) {
110 ps->pending_flush = 1;
113 sk_flush(ps->sub_socket);
116 static void sk_proxy_set_private_ptr (Socket s, void *ptr)
118 Proxy_Socket ps = (Proxy_Socket) s;
119 sk_set_private_ptr(ps->sub_socket, ptr);
122 static void * sk_proxy_get_private_ptr (Socket s)
124 Proxy_Socket ps = (Proxy_Socket) s;
125 return sk_get_private_ptr(ps->sub_socket);
128 static void sk_proxy_set_frozen (Socket s, int is_frozen)
130 Proxy_Socket ps = (Proxy_Socket) s;
132 if (ps->state != PROXY_STATE_ACTIVE) {
133 ps->freeze = is_frozen;
136 sk_set_frozen(ps->sub_socket, is_frozen);
139 static char * sk_proxy_socket_error (Socket s)
141 Proxy_Socket ps = (Proxy_Socket) s;
142 if (ps->error != NULL || ps->sub_socket == NULL) {
145 return sk_socket_error(ps->sub_socket);
148 /* basic proxy plug functions */
150 static int plug_proxy_closing (Plug p, char *error_msg,
151 int error_code, int calling_back)
153 Proxy_Plug pp = (Proxy_Plug) p;
154 Proxy_Socket ps = pp->proxy_socket;
156 if (ps->state != PROXY_STATE_ACTIVE) {
157 ps->closing_error_msg = error_msg;
158 ps->closing_error_code = error_code;
159 ps->closing_calling_back = calling_back;
160 return ps->negotiate(ps, PROXY_CHANGE_CLOSING);
162 return plug_closing(ps->plug, error_msg,
163 error_code, calling_back);
166 static int plug_proxy_receive (Plug p, int urgent, char *data, int len)
168 Proxy_Plug pp = (Proxy_Plug) p;
169 Proxy_Socket ps = pp->proxy_socket;
171 if (ps->state != PROXY_STATE_ACTIVE) {
172 /* we will lose the urgentness of this data, but since most,
173 * if not all, of this data will be consumed by the negotiation
174 * process, hopefully it won't affect the protocol above us
176 bufchain_add(&ps->pending_input_data, data, len);
177 ps->receive_urgent = urgent;
178 ps->receive_data = data;
179 ps->receive_len = len;
180 return ps->negotiate(ps, PROXY_CHANGE_RECEIVE);
182 return plug_receive(ps->plug, urgent, data, len);
185 static void plug_proxy_sent (Plug p, int bufsize)
187 Proxy_Plug pp = (Proxy_Plug) p;
188 Proxy_Socket ps = pp->proxy_socket;
190 if (ps->state != PROXY_STATE_ACTIVE) {
191 ps->sent_bufsize = bufsize;
192 ps->negotiate(ps, PROXY_CHANGE_SENT);
195 plug_sent(ps->plug, bufsize);
198 static int plug_proxy_accepting (Plug p, void *sock)
200 Proxy_Plug pp = (Proxy_Plug) p;
201 Proxy_Socket ps = pp->proxy_socket;
203 if (ps->state != PROXY_STATE_ACTIVE) {
204 ps->accepting_sock = sock;
205 return ps->negotiate(ps, PROXY_CHANGE_ACCEPTING);
207 return plug_accepting(ps->plug, sock);
210 static int proxy_for_destination (SockAddr addr, char * hostname, int port)
214 int hostip_len, hostname_len;
217 /* we want a string representation of the IP address for comparisons */
218 sk_getaddr(addr, hostip, 64);
220 hostip_len = strlen(hostip);
221 hostname_len = strlen(hostname);
223 exclude_list = cfg.proxy_exclude_list;
225 /* now parse the exclude list, and see if either our IP
226 * or hostname matches anything in it.
229 while (exclude_list[s]) {
230 while (exclude_list[s] &&
231 (isspace(exclude_list[s]) ||
232 exclude_list[s] == ',')) s++;
234 if (!exclude_list[s]) break;
238 while (exclude_list[e] &&
239 (isalnum(exclude_list[e]) ||
240 exclude_list[e] == '-' ||
241 exclude_list[e] == '.' ||
242 exclude_list[e] == '*')) e++;
244 if (exclude_list[s] == '*') {
245 /* wildcard at beginning of entry */
247 if (strnicmp(hostip + hostip_len - (e - s - 1),
248 exclude_list + s + 1, e - s - 1) == 0 ||
249 strnicmp(hostname + hostname_len - (e - s - 1),
250 exclude_list + s + 1, e - s - 1) == 0)
251 return 0; /* IP/hostname range excluded. do not use proxy. */
253 } else if (exclude_list[e-1] == '*') {
254 /* wildcard at end of entry */
256 if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 ||
257 strnicmp(hostname, exclude_list + s, e - s - 1) == 0)
258 return 0; /* IP/hostname range excluded. do not use proxy. */
261 /* no wildcard at either end, so let's try an absolute
262 * match (ie. a specific IP)
265 if (stricmp(hostip, exclude_list + s) == 0)
266 return 0; /* IP/hostname excluded. do not use proxy. */
267 if (stricmp(hostname, exclude_list + s) == 0)
268 return 0; /* IP/hostname excluded. do not use proxy. */
274 /* no matches in the exclude list, so use the proxy */
278 Socket new_connection(SockAddr addr, char *hostname,
279 int port, int privport,
280 int oobinline, int nodelay, Plug plug)
282 static struct socket_function_table socket_fn_table = {
288 sk_proxy_set_private_ptr,
289 sk_proxy_get_private_ptr,
291 sk_proxy_socket_error
294 static struct plug_function_table plug_fn_table = {
301 if (cfg.proxy_type != PROXY_NONE &&
302 proxy_for_destination(addr, hostname, port))
307 char * proxy_canonical_name;
309 ret = smalloc(sizeof(struct Socket_proxy_tag));
310 ret->fn = &socket_fn_table;
312 ret->remote_addr = addr;
313 ret->remote_port = port;
315 bufchain_init(&ret->pending_input_data);
316 bufchain_init(&ret->pending_output_data);
317 bufchain_init(&ret->pending_oob_output_data);
319 ret->sub_socket = NULL;
320 ret->state = PROXY_STATE_NEW;
322 if (cfg.proxy_type == PROXY_HTTP) {
323 ret->negotiate = proxy_http_negotiate;
324 } else if (cfg.proxy_type == PROXY_SOCKS) {
325 if (cfg.proxy_socks_version == 4)
326 ret->negotiate = proxy_socks4_negotiate;
328 ret->negotiate = proxy_socks5_negotiate;
329 } else if (cfg.proxy_type == PROXY_TELNET) {
330 ret->negotiate = proxy_telnet_negotiate;
332 ret->error = "Network error: Unknown proxy method";
336 /* create the proxy plug to map calls from the actual
337 * socket into our proxy socket layer */
338 pplug = smalloc(sizeof(struct Plug_proxy_tag));
339 pplug->fn = &plug_fn_table;
340 pplug->proxy_socket = ret;
343 proxy_addr = sk_namelookup(cfg.proxy_host,
344 &proxy_canonical_name);
345 sfree(proxy_canonical_name);
347 /* create the actual socket we will be using,
348 * connected to our proxy server and port.
350 ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port,
352 nodelay, (Plug) pplug);
353 if (sk_socket_error(ret->sub_socket) != NULL)
356 sk_addr_free(proxy_addr);
358 /* start the proxy negotiation process... */
359 sk_set_frozen(ret->sub_socket, 0);
360 ret->negotiate(ret, PROXY_CHANGE_NEW);
365 /* no proxy, so just return the direct socket */
366 return sk_new(addr, port, privport, oobinline, nodelay, plug);
369 Socket new_listener(int port, Plug plug, int local_host_only)
371 /* TODO: SOCKS (and potentially others) support inbound
372 * TODO: connections via the proxy. support them.
375 return sk_newlistener(port, plug, local_host_only);
378 /* ----------------------------------------------------------------------
379 * HTTP CONNECT proxy type.
382 static int get_line_end (char * data, int len)
388 if (data[off] == '\n') {
389 /* we have a newline */
392 /* is that the only thing on this line? */
393 if (off <= 2) return off;
395 /* if not, then there is the possibility that this header
396 * continues onto the next line, if it starts with a space
401 data[off+1] != ' ' &&
402 data[off+1] != '\t') return off;
404 /* the line does continue, so we have to keep going
405 * until we see an the header's "real" end of line.
416 int proxy_http_negotiate (Proxy_Socket p, int change)
418 if (p->state == PROXY_STATE_NEW) {
419 /* we are just beginning the proxy negotiate process,
420 * so we'll send off the initial bits of the request.
421 * for this proxy method, it's just a simple HTTP
424 char buf[256], dest[64];
426 sk_getaddr(p->remote_addr, dest, 64);
428 sprintf(buf, "CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n\r\n",
429 dest, p->remote_port, dest, p->remote_port);
430 sk_write(p->sub_socket, buf, strlen(buf));
436 if (change == PROXY_CHANGE_CLOSING) {
437 /* if our proxy negotiation process involves closing and opening
438 * new sockets, then we would want to intercept this closing
439 * callback when we were expecting it. if we aren't anticipating
440 * a socket close, then some error must have occurred. we'll
441 * just pass those errors up to the backend.
443 return plug_closing(p->plug, p->closing_error_msg,
444 p->closing_error_code,
445 p->closing_calling_back);
448 if (change == PROXY_CHANGE_SENT) {
449 /* some (or all) of what we wrote to the proxy was sent.
450 * we don't do anything new, however, until we receive the
451 * proxy's response. we might want to set a timer so we can
452 * timeout the proxy negotiation after a while...
457 if (change == PROXY_CHANGE_ACCEPTING) {
458 /* we should _never_ see this, as we are using our socket to
459 * connect to a proxy, not accepting inbound connections.
460 * what should we do? close the socket with an appropriate
463 return plug_accepting(p->plug, p->accepting_sock);
466 if (change == PROXY_CHANGE_RECEIVE) {
467 /* we have received data from the underlying socket, which
468 * we'll need to parse, process, and respond to appropriately.
477 int min_ver, maj_ver, status;
479 /* get the status line */
480 bufchain_prefix(&p->pending_input_data, &data, &len);
481 eol = get_line_end(data, len);
482 if (eol < 0) return 1;
484 sscanf((char *)data, "HTTP/%i.%i %i", &maj_ver, &min_ver, &status);
486 /* remove the status line from the input buffer. */
487 bufchain_consume(&p->pending_input_data, eol);
489 /* TODO: we need to support Proxy-Auth headers */
491 if (status < 200 || status > 299) {
493 /* TODO: return a more specific error message,
494 * TODO: based on the status code.
496 plug_closing(p->plug, "Network error: Error while communicating with proxy",
497 PROXY_ERROR_GENERAL, 0);
506 /* get headers. we're done when we get a
507 * header of length 2, (ie. just "\r\n")
510 bufchain_prefix(&p->pending_input_data, &data, &len);
511 eol = get_line_end(data, len);
514 /* TODO: Proxy-Auth stuff. in some cases, we will
515 * TODO: need to extract information from headers.
517 bufchain_consume(&p->pending_input_data, eol);
518 bufchain_prefix(&p->pending_input_data, &data, &len);
519 eol = get_line_end(data, len);
524 bufchain_consume(&p->pending_input_data, 2);
526 /* proxy activate will have dealt with
527 * whatever is left of the buffer */
535 plug_closing(p->plug, "Network error: Unexpected proxy error",
536 PROXY_ERROR_UNEXPECTED, 0);
540 /* ----------------------------------------------------------------------
544 /* SOCKS version 4 */
545 int proxy_socks4_negotiate (Proxy_Socket p, int change)
547 if (p->state == PROXY_CHANGE_NEW) {
550 * version number (1 byte) = 4
551 * command code (1 byte)
554 * dest. port (2 bytes) [network order]
555 * dest. address (4 bytes)
556 * user ID (variable length, null terminated string)
562 if (sk_addrtype(p->remote_addr) != AF_INET) {
563 plug_closing(p->plug, "Network error: SOCKS version 4 does not support IPv6",
564 PROXY_ERROR_GENERAL, 0);
568 length = strlen(cfg.proxy_username) + 9;
569 command = (char*) malloc(length);
570 strcpy(command + 8, cfg.proxy_username);
572 command[0] = 4; /* version 4 */
573 command[1] = 1; /* CONNECT command */
576 command[2] = (char) (p->remote_port >> 8) & 0xff;
577 command[3] = (char) p->remote_port & 0xff;
580 sk_addrcopy(p->remote_addr, command + 4);
582 sk_write(p->sub_socket, command, length);
589 if (change == PROXY_CHANGE_CLOSING) {
590 /* if our proxy negotiation process involves closing and opening
591 * new sockets, then we would want to intercept this closing
592 * callback when we were expecting it. if we aren't anticipating
593 * a socket close, then some error must have occurred. we'll
594 * just pass those errors up to the backend.
596 return plug_closing(p->plug, p->closing_error_msg,
597 p->closing_error_code,
598 p->closing_calling_back);
601 if (change == PROXY_CHANGE_SENT) {
602 /* some (or all) of what we wrote to the proxy was sent.
603 * we don't do anything new, however, until we receive the
604 * proxy's response. we might want to set a timer so we can
605 * timeout the proxy negotiation after a while...
610 if (change == PROXY_CHANGE_ACCEPTING) {
611 /* we should _never_ see this, as we are using our socket to
612 * connect to a proxy, not accepting inbound connections.
613 * what should we do? close the socket with an appropriate
616 return plug_accepting(p->plug, p->accepting_sock);
619 if (change == PROXY_CHANGE_RECEIVE) {
620 /* we have received data from the underlying socket, which
621 * we'll need to parse, process, and respond to appropriately.
626 * version number (1 byte) = 4
627 * reply code (1 byte)
628 * 90 = request granted
629 * 91 = request rejected or failed
630 * 92 = request rejected due to lack of IDENTD on client
631 * 93 = request rejected due to difference in user ID
632 * (what we sent vs. what IDENTD said)
633 * dest. port (2 bytes)
634 * dest. address (4 bytes)
640 /* get the response */
641 bufchain_prefix(&p->pending_input_data, &data, &len);
644 plug_closing(p->plug, "Network error: SOCKS proxy responded with "
645 "unexpected reply code version",
646 PROXY_ERROR_GENERAL, 0);
654 plug_closing(p->plug, "Network error: SOCKS server wanted IDENTD on client",
655 PROXY_ERROR_GENERAL, 0);
658 plug_closing(p->plug, "Network error: Username and IDENTD on client don't agree",
659 PROXY_ERROR_GENERAL, 0);
663 plug_closing(p->plug, "Network error: Error while communicating with proxy",
664 PROXY_ERROR_GENERAL, 0);
673 /* proxy activate will have dealt with
674 * whatever is left of the buffer */
679 plug_closing(p->plug, "Network error: Unexpected proxy error",
680 PROXY_ERROR_UNEXPECTED, 0);
684 /* SOCKS version 5 */
685 int proxy_socks5_negotiate (Proxy_Socket p, int change)
687 if (p->state == PROXY_CHANGE_NEW) {
690 * version number (1 byte) = 5
691 * number of available authentication methods (1 byte)
692 * available authentication methods (1 byte * previous value)
693 * authentication methods:
694 * 0x00 = no authentication
696 * 0x02 = username/password
702 command[0] = 5; /* version 5 */
703 command[1] = 1; /* TODO: we don't currently support any auth methods */
704 command[2] = 0x00; /* no authentication */
706 sk_write(p->sub_socket, command, 3);
712 if (change == PROXY_CHANGE_CLOSING) {
713 /* if our proxy negotiation process involves closing and opening
714 * new sockets, then we would want to intercept this closing
715 * callback when we were expecting it. if we aren't anticipating
716 * a socket close, then some error must have occurred. we'll
717 * just pass those errors up to the backend.
719 return plug_closing(p->plug, p->closing_error_msg,
720 p->closing_error_code,
721 p->closing_calling_back);
724 if (change == PROXY_CHANGE_SENT) {
725 /* some (or all) of what we wrote to the proxy was sent.
726 * we don't do anything new, however, until we receive the
727 * proxy's response. we might want to set a timer so we can
728 * timeout the proxy negotiation after a while...
733 if (change == PROXY_CHANGE_ACCEPTING) {
734 /* we should _never_ see this, as we are using our socket to
735 * connect to a proxy, not accepting inbound connections.
736 * what should we do? close the socket with an appropriate
739 return plug_accepting(p->plug, p->accepting_sock);
742 if (change == PROXY_CHANGE_RECEIVE) {
743 /* we have received data from the underlying socket, which
744 * we'll need to parse, process, and respond to appropriately.
753 * version number (1 byte) = 5
754 * authentication method (1 byte)
755 * authentication methods:
756 * 0x00 = no authentication
758 * 0x02 = username/password
760 * 0xff = no acceptable methods
763 /* get the response */
764 bufchain_prefix(&p->pending_input_data, &data, &len);
767 plug_closing(p->plug, "Network error: Error while communicating with proxy",
768 PROXY_ERROR_GENERAL, 0);
772 if (data[1] == 0x00) p->state = 2; /* no authentication needed */
773 else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */
774 else if (data[1] == 0x02) p->state = 5; /* username/password authentication */
775 else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */
777 plug_closing(p->plug, "Network error: We don't support any of the SOCKS "
778 "server's authentication methods",
779 PROXY_ERROR_GENERAL, 0);
787 * version number (1 byte) = 5
788 * command code (1 byte)
792 * reserved (1 byte) = 0x00
793 * address type (1 byte)
795 * 3 = domainname (first byte has length, no terminating null)
797 * dest. address (variable)
798 * dest. port (2 bytes) [network order]
804 if (sk_addrtype(p->remote_addr) == AF_INET) {
806 command[3] = 1; /* IPv4 */
809 command[3] = 4; /* IPv6 */
812 command[0] = 5; /* version 5 */
813 command[1] = 1; /* CONNECT command */
817 sk_addrcopy(p->remote_addr, command+4);
820 command[len-2] = (char) (p->remote_port >> 8) & 0xff;
821 command[len-1] = (char) p->remote_port & 0xff;
823 sk_write(p->sub_socket, command, len);
832 * version number (1 bytes) = 5
833 * reply code (1 byte)
835 * 1 = general SOCKS server failure
836 * 2 = connection not allowed by ruleset
837 * 3 = network unreachable
838 * 4 = host unreachable
839 * 5 = connection refused
841 * 7 = command not supported
842 * 8 = address type not supported
843 * reserved (1 byte) = x00
844 * address type (1 byte)
846 * 3 = domainname (first byte has length, no terminating null)
848 * server bound address (variable)
849 * server bound port (2 bytes) [network order]
852 /* get the response */
853 bufchain_prefix(&p->pending_input_data, &data, &len);
856 plug_closing(p->plug, "Network error: Error while communicating with proxy",
857 PROXY_ERROR_GENERAL, 0);
873 plug_closing(p->plug, "Network error: Error while communicating with proxy",
874 PROXY_ERROR_GENERAL, 0);
883 /* proxy activate will have dealt with
884 * whatever is left of the buffer */
889 /* TODO: Handle GSSAPI authentication */
890 plug_closing(p->plug, "Network error: We don't support GSSAPI authentication",
891 PROXY_ERROR_GENERAL, 0);
896 /* TODO: Handle username/password authentication */
897 plug_closing(p->plug, "Network error: We don't support username/password "
899 PROXY_ERROR_GENERAL, 0);
904 /* TODO: Handle CHAP authentication */
905 plug_closing(p->plug, "Network error: We don't support CHAP authentication",
906 PROXY_ERROR_GENERAL, 0);
911 plug_closing(p->plug, "Network error: Unexpected proxy error",
912 PROXY_ERROR_UNEXPECTED, 0);
916 /* ----------------------------------------------------------------------
917 * `Telnet' proxy type.
919 * (This is for ad-hoc proxies where you connect to the proxy's
920 * telnet port and send a command such as `connect host port'. The
921 * command is configurable, since this proxy type is typically not
922 * standardised or at all well-defined.)
925 int proxy_telnet_negotiate (Proxy_Socket p, int change)
927 if (p->state == PROXY_CHANGE_NEW) {
931 /* we need to escape \\, \%, \r, \n, \t, \x??, \0???,
932 * %%, %host, and %port
935 while (cfg.proxy_telnet_command[eo] != 0) {
937 /* scan forward until we hit end-of-line,
938 * or an escape character (\ or %) */
939 while (cfg.proxy_telnet_command[eo] != 0 &&
940 cfg.proxy_telnet_command[eo] != '%' &&
941 cfg.proxy_telnet_command[eo] != '\\') eo++;
943 /* if we hit eol, break out of our escaping loop */
944 if (cfg.proxy_telnet_command[eo] == 0) break;
946 /* if there was any unescaped text before the escape
947 * character, send that now */
949 sk_write(p->sub_socket,
950 cfg.proxy_telnet_command + so, eo - so);
955 /* if the escape character was the last character of
956 * the line, we'll just stop and send it. */
957 if (cfg.proxy_telnet_command[eo] == 0) break;
959 if (cfg.proxy_telnet_command[so] == '\\') {
961 /* we recognize \\, \%, \r, \n, \t, \x??.
962 * anything else, we just send unescaped (including the \).
965 switch (cfg.proxy_telnet_command[eo]) {
968 sk_write(p->sub_socket, "\\", 1);
973 sk_write(p->sub_socket, "%%", 1);
978 sk_write(p->sub_socket, "\r", 1);
983 sk_write(p->sub_socket, "\n", 1);
988 sk_write(p->sub_socket, "\t", 1);
995 /* escaped hexadecimal value (ie. \xff) */
1001 if (cfg.proxy_telnet_command[eo] >= '0' &&
1002 cfg.proxy_telnet_command[eo] <= '9')
1003 v += cfg.proxy_telnet_command[eo] - '0';
1004 else if (cfg.proxy_telnet_command[eo] >= 'a' &&
1005 cfg.proxy_telnet_command[eo] <= 'f')
1006 v += cfg.proxy_telnet_command[eo] - 'a' + 10;
1007 else if (cfg.proxy_telnet_command[eo] >= 'A' &&
1008 cfg.proxy_telnet_command[eo] <= 'F')
1009 v += cfg.proxy_telnet_command[eo] - 'A' + 10;
1011 /* non hex character, so we abort and just
1012 * send the whole thing unescaped (including \x)
1014 sk_write(p->sub_socket, "\\", 1);
1019 /* we only extract two hex characters */
1021 sk_write(p->sub_socket, &v, 1);
1033 sk_write(p->sub_socket,
1034 cfg.proxy_telnet_command + so, 2);
1040 /* % escape. we recognize %%, %host, %port. anything else,
1041 * we just send unescaped (including the %). */
1043 if (cfg.proxy_telnet_command[eo] == '%') {
1044 sk_write(p->sub_socket, "%", 1);
1047 else if (strnicmp(cfg.proxy_telnet_command + eo,
1050 sk_getaddr(p->remote_addr, dest, 64);
1051 sk_write(p->sub_socket, dest, strlen(dest));
1054 else if (strnicmp(cfg.proxy_telnet_command + eo,
1057 sprintf(port, "%i", p->remote_port);
1058 sk_write(p->sub_socket, port, strlen(port));
1062 /* we don't escape this, so send the % now, and
1063 * don't advance eo, so that we'll consider the
1064 * text immediately following the % as unescaped.
1066 sk_write(p->sub_socket, "%", 1);
1070 /* resume scanning for additional escapes after this one. */
1074 /* if there is any unescaped text at the end of the line, send it */
1076 sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so);
1083 if (change == PROXY_CHANGE_CLOSING) {
1084 /* if our proxy negotiation process involves closing and opening
1085 * new sockets, then we would want to intercept this closing
1086 * callback when we were expecting it. if we aren't anticipating
1087 * a socket close, then some error must have occurred. we'll
1088 * just pass those errors up to the backend.
1090 return plug_closing(p->plug, p->closing_error_msg,
1091 p->closing_error_code,
1092 p->closing_calling_back);
1095 if (change == PROXY_CHANGE_SENT) {
1096 /* some (or all) of what we wrote to the proxy was sent.
1097 * we don't do anything new, however, until we receive the
1098 * proxy's response. we might want to set a timer so we can
1099 * timeout the proxy negotiation after a while...
1104 if (change == PROXY_CHANGE_ACCEPTING) {
1105 /* we should _never_ see this, as we are using our socket to
1106 * connect to a proxy, not accepting inbound connections.
1107 * what should we do? close the socket with an appropriate
1110 return plug_accepting(p->plug, p->accepting_sock);
1113 if (change == PROXY_CHANGE_RECEIVE) {
1114 /* we have received data from the underlying socket, which
1115 * we'll need to parse, process, and respond to appropriately.
1120 /* proxy activate will have dealt with
1121 * whatever is left of the buffer */
1125 plug_closing(p->plug, "Network error: Unexpected proxy error",
1126 PROXY_ERROR_UNEXPECTED, 0);