8eebd221 |
1 | /* |
2 | * Network proxy abstraction in PuTTY |
3 | * |
4 | * A proxy layer, if necessary, wedges itself between the network |
5 | * code and the higher level backend. |
6 | */ |
7 | |
8 | #include <windows.h> |
9 | |
7983f47e |
10 | #include <assert.h> |
11 | |
8eebd221 |
12 | #define DEFINE_PLUG_METHOD_MACROS |
13 | #include "putty.h" |
14 | #include "network.h" |
15 | #include "proxy.h" |
16 | |
17 | /* |
18 | * Call this when proxy negotiation is complete, so that this |
19 | * socket can begin working normally. |
20 | */ |
21 | void proxy_activate (Proxy_Socket p) |
22 | { |
23 | void *data; |
24 | int len; |
25 | |
8eebd221 |
26 | p->state = PROXY_STATE_ACTIVE; |
27 | |
28 | /* let's try to keep extra receive events from coming through */ |
29 | sk_set_frozen(p->sub_socket, 1); |
30 | |
0e8f4cda |
31 | /* send buffered OOB writes */ |
8eebd221 |
32 | while (bufchain_size(&p->pending_oob_output_data) > 0) { |
33 | bufchain_prefix(&p->pending_oob_output_data, &data, &len); |
34 | sk_write_oob(p->sub_socket, data, len); |
35 | bufchain_consume(&p->pending_oob_output_data, len); |
36 | } |
37 | bufchain_clear(&p->pending_oob_output_data); |
38 | |
0e8f4cda |
39 | /* send buffered normal writes */ |
8eebd221 |
40 | while (bufchain_size(&p->pending_output_data) > 0) { |
41 | bufchain_prefix(&p->pending_output_data, &data, &len); |
42 | sk_write(p->sub_socket, data, len); |
43 | bufchain_consume(&p->pending_output_data, len); |
44 | } |
45 | bufchain_clear(&p->pending_output_data); |
46 | |
0e8f4cda |
47 | /* if we were asked to flush the output during |
48 | * the proxy negotiation process, do so now. |
49 | */ |
8eebd221 |
50 | if (p->pending_flush) sk_flush(p->sub_socket); |
8eebd221 |
51 | |
0e8f4cda |
52 | /* forward buffered recv data to the backend */ |
8eebd221 |
53 | while (bufchain_size(&p->pending_input_data) > 0) { |
54 | bufchain_prefix(&p->pending_input_data, &data, &len); |
55 | plug_receive(p->plug, 0, data, len); |
56 | bufchain_consume(&p->pending_input_data, len); |
57 | } |
58 | bufchain_clear(&p->pending_input_data); |
8eebd221 |
59 | |
60 | /* now set the underlying socket to whatever freeze state they wanted */ |
61 | sk_set_frozen(p->sub_socket, p->freeze); |
8eebd221 |
62 | } |
63 | |
64 | /* basic proxy socket functions */ |
65 | |
66 | static Plug sk_proxy_plug (Socket s, Plug p) |
67 | { |
68 | Proxy_Socket ps = (Proxy_Socket) s; |
69 | Plug ret = ps->plug; |
70 | if (p) |
71 | ps->plug = p; |
72 | return ret; |
73 | } |
74 | |
75 | static void sk_proxy_close (Socket s) |
76 | { |
77 | Proxy_Socket ps = (Proxy_Socket) s; |
78 | |
8eebd221 |
79 | sk_close(ps->sub_socket); |
80 | sfree(ps); |
81 | } |
82 | |
83 | static int sk_proxy_write (Socket s, char *data, int len) |
84 | { |
85 | Proxy_Socket ps = (Proxy_Socket) s; |
86 | |
8eebd221 |
87 | if (ps->state != PROXY_STATE_ACTIVE) { |
88 | bufchain_add(&ps->pending_output_data, data, len); |
89 | return bufchain_size(&ps->pending_output_data); |
90 | } |
91 | return sk_write(ps->sub_socket, data, len); |
92 | } |
93 | |
94 | static int sk_proxy_write_oob (Socket s, char *data, int len) |
95 | { |
96 | Proxy_Socket ps = (Proxy_Socket) s; |
97 | |
8eebd221 |
98 | if (ps->state != PROXY_STATE_ACTIVE) { |
99 | bufchain_clear(&ps->pending_output_data); |
100 | bufchain_clear(&ps->pending_oob_output_data); |
101 | bufchain_add(&ps->pending_oob_output_data, data, len); |
102 | return len; |
103 | } |
104 | return sk_write_oob(ps->sub_socket, data, len); |
105 | } |
106 | |
107 | static void sk_proxy_flush (Socket s) |
108 | { |
109 | Proxy_Socket ps = (Proxy_Socket) s; |
110 | |
8eebd221 |
111 | if (ps->state != PROXY_STATE_ACTIVE) { |
112 | ps->pending_flush = 1; |
113 | return; |
114 | } |
115 | sk_flush(ps->sub_socket); |
116 | } |
117 | |
118 | static void sk_proxy_set_private_ptr (Socket s, void *ptr) |
119 | { |
120 | Proxy_Socket ps = (Proxy_Socket) s; |
121 | sk_set_private_ptr(ps->sub_socket, ptr); |
122 | } |
123 | |
124 | static void * sk_proxy_get_private_ptr (Socket s) |
125 | { |
126 | Proxy_Socket ps = (Proxy_Socket) s; |
127 | return sk_get_private_ptr(ps->sub_socket); |
128 | } |
129 | |
130 | static void sk_proxy_set_frozen (Socket s, int is_frozen) |
131 | { |
132 | Proxy_Socket ps = (Proxy_Socket) s; |
133 | |
8eebd221 |
134 | if (ps->state != PROXY_STATE_ACTIVE) { |
135 | ps->freeze = is_frozen; |
136 | return; |
137 | } |
138 | sk_set_frozen(ps->sub_socket, is_frozen); |
139 | } |
140 | |
141 | static char * sk_proxy_socket_error (Socket s) |
142 | { |
143 | Proxy_Socket ps = (Proxy_Socket) s; |
144 | if (ps->error != NULL || ps->sub_socket == NULL) { |
145 | return ps->error; |
146 | } |
147 | return sk_socket_error(ps->sub_socket); |
148 | } |
149 | |
150 | /* basic proxy plug functions */ |
151 | |
152 | static int plug_proxy_closing (Plug p, char *error_msg, |
153 | int error_code, int calling_back) |
154 | { |
155 | Proxy_Plug pp = (Proxy_Plug) p; |
156 | Proxy_Socket ps = pp->proxy_socket; |
157 | |
8eebd221 |
158 | if (ps->state != PROXY_STATE_ACTIVE) { |
159 | ps->closing_error_msg = error_msg; |
160 | ps->closing_error_code = error_code; |
161 | ps->closing_calling_back = calling_back; |
162 | return ps->negotiate(ps, PROXY_CHANGE_CLOSING); |
163 | } |
164 | return plug_closing(ps->plug, error_msg, |
165 | error_code, calling_back); |
166 | } |
167 | |
168 | static int plug_proxy_receive (Plug p, int urgent, char *data, int len) |
169 | { |
170 | Proxy_Plug pp = (Proxy_Plug) p; |
171 | Proxy_Socket ps = pp->proxy_socket; |
172 | |
8eebd221 |
173 | if (ps->state != PROXY_STATE_ACTIVE) { |
174 | /* we will lose the urgentness of this data, but since most, |
175 | * if not all, of this data will be consumed by the negotiation |
176 | * process, hopefully it won't affect the protocol above us |
177 | */ |
178 | bufchain_add(&ps->pending_input_data, data, len); |
179 | ps->receive_urgent = urgent; |
180 | ps->receive_data = data; |
181 | ps->receive_len = len; |
182 | return ps->negotiate(ps, PROXY_CHANGE_RECEIVE); |
183 | } |
184 | return plug_receive(ps->plug, urgent, data, len); |
185 | } |
186 | |
187 | static void plug_proxy_sent (Plug p, int bufsize) |
188 | { |
189 | Proxy_Plug pp = (Proxy_Plug) p; |
190 | Proxy_Socket ps = pp->proxy_socket; |
191 | |
8eebd221 |
192 | if (ps->state != PROXY_STATE_ACTIVE) { |
193 | ps->sent_bufsize = bufsize; |
194 | ps->negotiate(ps, PROXY_CHANGE_SENT); |
195 | return; |
196 | } |
197 | plug_sent(ps->plug, bufsize); |
198 | } |
199 | |
200 | static int plug_proxy_accepting (Plug p, void *sock) |
201 | { |
202 | Proxy_Plug pp = (Proxy_Plug) p; |
203 | Proxy_Socket ps = pp->proxy_socket; |
204 | |
8eebd221 |
205 | if (ps->state != PROXY_STATE_ACTIVE) { |
206 | ps->accepting_sock = sock; |
207 | return ps->negotiate(ps, PROXY_CHANGE_ACCEPTING); |
208 | } |
209 | return plug_accepting(ps->plug, sock); |
210 | } |
211 | |
212 | static int proxy_for_destination (SockAddr addr, char * hostname, int port) |
213 | { |
214 | int s = 0, e = 0; |
215 | char hostip[64]; |
216 | int hostip_len, hostname_len; |
217 | char * exclude_list; |
218 | |
219 | /* we want a string representation of the IP address for comparisons */ |
220 | sk_getaddr(addr, hostip, 64); |
221 | |
222 | hostip_len = strlen(hostip); |
223 | hostname_len = strlen(hostname); |
224 | |
225 | exclude_list = cfg.proxy_exclude_list; |
226 | |
227 | /* now parse the exclude list, and see if either our IP |
228 | * or hostname matches anything in it. |
229 | */ |
230 | |
231 | while (exclude_list[s]) { |
232 | while (exclude_list[s] && |
233 | (isspace(exclude_list[s]) || |
234 | exclude_list[s] == ',')) s++; |
235 | |
236 | if (!exclude_list[s]) break; |
237 | |
238 | e = s; |
239 | |
240 | while (exclude_list[e] && |
241 | (isalnum(exclude_list[e]) || |
242 | exclude_list[e] == '-' || |
243 | exclude_list[e] == '.' || |
244 | exclude_list[e] == '*')) e++; |
245 | |
246 | if (exclude_list[s] == '*') { |
247 | /* wildcard at beginning of entry */ |
248 | |
249 | if (strnicmp(hostip + hostip_len - (e - s - 1), |
250 | exclude_list + s + 1, e - s - 1) == 0 || |
251 | strnicmp(hostname + hostname_len - (e - s - 1), |
252 | exclude_list + s + 1, e - s - 1) == 0) |
253 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
254 | |
255 | } else if (exclude_list[e-1] == '*') { |
256 | /* wildcard at end of entry */ |
257 | |
258 | if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 || |
259 | strnicmp(hostname, exclude_list + s, e - s - 1) == 0) |
260 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
261 | |
262 | } else { |
263 | /* no wildcard at either end, so let's try an absolute |
264 | * match (ie. a specific IP) |
265 | */ |
266 | |
267 | if (stricmp(hostip, exclude_list + s) == 0) |
268 | return 0; /* IP/hostname excluded. do not use proxy. */ |
269 | if (stricmp(hostname, exclude_list + s) == 0) |
270 | return 0; /* IP/hostname excluded. do not use proxy. */ |
271 | } |
272 | |
273 | s = e; |
274 | } |
275 | |
276 | /* no matches in the exclude list, so use the proxy */ |
277 | return 1; |
278 | } |
279 | |
280 | Socket new_connection(SockAddr addr, char *hostname, |
281 | int port, int privport, |
282 | int oobinline, int nodelay, Plug plug) |
283 | { |
284 | static struct socket_function_table socket_fn_table = { |
285 | sk_proxy_plug, |
286 | sk_proxy_close, |
287 | sk_proxy_write, |
288 | sk_proxy_write_oob, |
289 | sk_proxy_flush, |
290 | sk_proxy_set_private_ptr, |
291 | sk_proxy_get_private_ptr, |
292 | sk_proxy_set_frozen, |
293 | sk_proxy_socket_error |
294 | }; |
295 | |
296 | static struct plug_function_table plug_fn_table = { |
297 | plug_proxy_closing, |
298 | plug_proxy_receive, |
299 | plug_proxy_sent, |
300 | plug_proxy_accepting |
301 | }; |
302 | |
303 | if (cfg.proxy_type != PROXY_NONE && |
304 | proxy_for_destination(addr, hostname, port)) |
305 | { |
306 | Proxy_Socket ret; |
307 | Proxy_Plug pplug; |
308 | SockAddr proxy_addr; |
309 | char * proxy_canonical_name; |
310 | |
311 | ret = smalloc(sizeof(struct Socket_proxy_tag)); |
312 | ret->fn = &socket_fn_table; |
313 | ret->plug = plug; |
314 | ret->remote_addr = addr; |
315 | ret->remote_port = port; |
316 | |
65c78e88 |
317 | /* XXX review these initialisations, and initialise other fields |
318 | * in Proxy_Socket structure */ |
319 | ret->error = NULL; |
320 | ret->pending_flush = 0; |
321 | ret->freeze = 0; |
322 | |
8eebd221 |
323 | bufchain_init(&ret->pending_input_data); |
324 | bufchain_init(&ret->pending_output_data); |
325 | bufchain_init(&ret->pending_oob_output_data); |
326 | |
8eebd221 |
327 | ret->sub_socket = NULL; |
328 | ret->state = PROXY_STATE_NEW; |
329 | |
330 | if (cfg.proxy_type == PROXY_HTTP) { |
331 | ret->negotiate = proxy_http_negotiate; |
332 | } else if (cfg.proxy_type == PROXY_SOCKS) { |
6971bbe7 |
333 | if (cfg.proxy_socks_version == 4) |
334 | ret->negotiate = proxy_socks4_negotiate; |
335 | else |
336 | ret->negotiate = proxy_socks5_negotiate; |
8eebd221 |
337 | } else if (cfg.proxy_type == PROXY_TELNET) { |
338 | ret->negotiate = proxy_telnet_negotiate; |
339 | } else { |
7983f47e |
340 | ret->error = "Proxy error: Unknown proxy method"; |
8eebd221 |
341 | return (Socket) ret; |
342 | } |
343 | |
344 | /* create the proxy plug to map calls from the actual |
345 | * socket into our proxy socket layer */ |
346 | pplug = smalloc(sizeof(struct Plug_proxy_tag)); |
347 | pplug->fn = &plug_fn_table; |
348 | pplug->proxy_socket = ret; |
349 | |
350 | /* look-up proxy */ |
351 | proxy_addr = sk_namelookup(cfg.proxy_host, |
352 | &proxy_canonical_name); |
353 | sfree(proxy_canonical_name); |
354 | |
355 | /* create the actual socket we will be using, |
356 | * connected to our proxy server and port. |
357 | */ |
358 | ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port, |
359 | privport, oobinline, |
360 | nodelay, (Plug) pplug); |
361 | if (sk_socket_error(ret->sub_socket) != NULL) |
362 | return (Socket) ret; |
363 | |
364 | sk_addr_free(proxy_addr); |
365 | |
366 | /* start the proxy negotiation process... */ |
367 | sk_set_frozen(ret->sub_socket, 0); |
368 | ret->negotiate(ret, PROXY_CHANGE_NEW); |
369 | |
370 | return (Socket) ret; |
371 | } |
372 | |
373 | /* no proxy, so just return the direct socket */ |
374 | return sk_new(addr, port, privport, oobinline, nodelay, plug); |
375 | } |
376 | |
377 | Socket new_listener(int port, Plug plug, int local_host_only) |
378 | { |
379 | /* TODO: SOCKS (and potentially others) support inbound |
380 | * TODO: connections via the proxy. support them. |
381 | */ |
382 | |
383 | return sk_newlistener(port, plug, local_host_only); |
384 | } |
385 | |
386 | /* ---------------------------------------------------------------------- |
387 | * HTTP CONNECT proxy type. |
388 | */ |
389 | |
390 | static int get_line_end (char * data, int len) |
391 | { |
392 | int off = 0; |
393 | |
394 | while (off < len) |
395 | { |
396 | if (data[off] == '\n') { |
397 | /* we have a newline */ |
398 | off++; |
399 | |
400 | /* is that the only thing on this line? */ |
401 | if (off <= 2) return off; |
402 | |
403 | /* if not, then there is the possibility that this header |
404 | * continues onto the next line, if it starts with a space |
405 | * or a tab. |
406 | */ |
407 | |
408 | if (off + 1 < len && |
409 | data[off+1] != ' ' && |
410 | data[off+1] != '\t') return off; |
411 | |
412 | /* the line does continue, so we have to keep going |
413 | * until we see an the header's "real" end of line. |
414 | */ |
415 | off++; |
416 | } |
417 | |
418 | off++; |
419 | } |
420 | |
421 | return -1; |
422 | } |
423 | |
424 | int proxy_http_negotiate (Proxy_Socket p, int change) |
425 | { |
426 | if (p->state == PROXY_STATE_NEW) { |
427 | /* we are just beginning the proxy negotiate process, |
428 | * so we'll send off the initial bits of the request. |
429 | * for this proxy method, it's just a simple HTTP |
430 | * request |
431 | */ |
0e8f4cda |
432 | char buf[256], dest[64]; |
8eebd221 |
433 | |
0e8f4cda |
434 | sk_getaddr(p->remote_addr, dest, 64); |
8eebd221 |
435 | |
1549e076 |
436 | sprintf(buf, "CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n", |
8eebd221 |
437 | dest, p->remote_port, dest, p->remote_port); |
438 | sk_write(p->sub_socket, buf, strlen(buf)); |
439 | |
1549e076 |
440 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
441 | char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)]; |
442 | char buf2[sizeof(buf)*4/3 + 100]; |
443 | int i, j, len; |
444 | sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password); |
445 | len = strlen(buf); |
446 | sprintf(buf2, "Proxy-Authorization: basic "); |
447 | for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4) |
448 | base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j); |
449 | strcpy(buf2+j, "\r\n"); |
450 | sk_write(p->sub_socket, buf2, strlen(buf2)); |
451 | } |
452 | |
453 | sprintf(buf, "\r\n"); |
454 | sk_write(p->sub_socket, buf, strlen(buf)); |
455 | |
8eebd221 |
456 | p->state = 1; |
8eebd221 |
457 | return 0; |
458 | } |
459 | |
460 | if (change == PROXY_CHANGE_CLOSING) { |
461 | /* if our proxy negotiation process involves closing and opening |
462 | * new sockets, then we would want to intercept this closing |
463 | * callback when we were expecting it. if we aren't anticipating |
464 | * a socket close, then some error must have occurred. we'll |
465 | * just pass those errors up to the backend. |
466 | */ |
467 | return plug_closing(p->plug, p->closing_error_msg, |
468 | p->closing_error_code, |
469 | p->closing_calling_back); |
470 | } |
471 | |
472 | if (change == PROXY_CHANGE_SENT) { |
473 | /* some (or all) of what we wrote to the proxy was sent. |
474 | * we don't do anything new, however, until we receive the |
475 | * proxy's response. we might want to set a timer so we can |
476 | * timeout the proxy negotiation after a while... |
477 | */ |
478 | return 0; |
479 | } |
480 | |
481 | if (change == PROXY_CHANGE_ACCEPTING) { |
482 | /* we should _never_ see this, as we are using our socket to |
483 | * connect to a proxy, not accepting inbound connections. |
484 | * what should we do? close the socket with an appropriate |
485 | * error message? |
486 | */ |
487 | return plug_accepting(p->plug, p->accepting_sock); |
488 | } |
489 | |
490 | if (change == PROXY_CHANGE_RECEIVE) { |
491 | /* we have received data from the underlying socket, which |
492 | * we'll need to parse, process, and respond to appropriately. |
493 | */ |
494 | |
7983f47e |
495 | char *data, *datap; |
8eebd221 |
496 | int len; |
497 | int eol; |
498 | |
499 | if (p->state == 1) { |
500 | |
501 | int min_ver, maj_ver, status; |
502 | |
503 | /* get the status line */ |
7983f47e |
504 | len = bufchain_size(&p->pending_input_data); |
505 | assert(len > 0); /* or we wouldn't be here */ |
506 | data = smalloc(len); |
507 | bufchain_fetch(&p->pending_input_data, data, len); |
508 | |
8eebd221 |
509 | eol = get_line_end(data, len); |
7983f47e |
510 | if (eol < 0) { |
511 | sfree(data); |
512 | return 1; |
513 | } |
8eebd221 |
514 | |
7983f47e |
515 | status = -1; |
516 | /* We can't rely on whether the %n incremented the sscanf return */ |
517 | if (sscanf((char *)data, "HTTP/%i.%i %n", |
518 | &maj_ver, &min_ver, &status) < 2 || status == -1) { |
519 | plug_closing(p->plug, "Proxy error: HTTP response was absent", |
520 | PROXY_ERROR_GENERAL, 0); |
521 | sfree(data); |
522 | return 1; |
523 | } |
8eebd221 |
524 | |
525 | /* remove the status line from the input buffer. */ |
526 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
527 | if (data[status] != '2') { |
8eebd221 |
528 | /* error */ |
7983f47e |
529 | char buf[1024]; |
530 | data[eol] = '\0'; |
531 | while (eol > status && |
532 | (data[eol-1] == '\r' || data[eol-1] == '\n')) |
533 | data[--eol] = '\0'; |
534 | sprintf(buf, "Proxy error: %.900s", |
535 | data+status); |
536 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
537 | sfree(data); |
8eebd221 |
538 | return 1; |
539 | } |
540 | |
7983f47e |
541 | sfree(data); |
542 | |
8eebd221 |
543 | p->state = 2; |
544 | } |
545 | |
546 | if (p->state == 2) { |
547 | |
548 | /* get headers. we're done when we get a |
549 | * header of length 2, (ie. just "\r\n") |
550 | */ |
551 | |
7983f47e |
552 | len = bufchain_size(&p->pending_input_data); |
553 | assert(len > 0); /* or we wouldn't be here */ |
554 | data = smalloc(len); |
555 | datap = data; |
556 | bufchain_fetch(&p->pending_input_data, data, len); |
557 | |
558 | eol = get_line_end(datap, len); |
559 | if (eol < 0) { |
560 | sfree(data); |
561 | return 1; |
562 | } |
8eebd221 |
563 | while (eol > 2) |
564 | { |
8eebd221 |
565 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
566 | datap += eol; |
567 | eol = get_line_end(datap, len); |
8eebd221 |
568 | } |
569 | |
570 | if (eol == 2) { |
571 | /* we're done */ |
572 | bufchain_consume(&p->pending_input_data, 2); |
573 | proxy_activate(p); |
574 | /* proxy activate will have dealt with |
575 | * whatever is left of the buffer */ |
7983f47e |
576 | sfree(data); |
8eebd221 |
577 | return 1; |
578 | } |
579 | |
7983f47e |
580 | sfree(data); |
8eebd221 |
581 | return 1; |
582 | } |
583 | } |
584 | |
7983f47e |
585 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
8eebd221 |
586 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
587 | return 1; |
8eebd221 |
588 | } |
589 | |
590 | /* ---------------------------------------------------------------------- |
6971bbe7 |
591 | * SOCKS proxy type. |
8eebd221 |
592 | */ |
593 | |
6971bbe7 |
594 | /* SOCKS version 4 */ |
595 | int proxy_socks4_negotiate (Proxy_Socket p, int change) |
8eebd221 |
596 | { |
6971bbe7 |
597 | if (p->state == PROXY_CHANGE_NEW) { |
598 | |
599 | /* request format: |
600 | * version number (1 byte) = 4 |
601 | * command code (1 byte) |
602 | * 1 = CONNECT |
603 | * 2 = BIND |
604 | * dest. port (2 bytes) [network order] |
605 | * dest. address (4 bytes) |
606 | * user ID (variable length, null terminated string) |
607 | */ |
608 | |
609 | int length; |
610 | char * command; |
611 | |
612 | if (sk_addrtype(p->remote_addr) != AF_INET) { |
7983f47e |
613 | plug_closing(p->plug, "Proxy error: SOCKS version 4 does" |
614 | " not support IPv6", PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
615 | return 1; |
616 | } |
617 | |
618 | length = strlen(cfg.proxy_username) + 9; |
619 | command = (char*) malloc(length); |
620 | strcpy(command + 8, cfg.proxy_username); |
621 | |
622 | command[0] = 4; /* version 4 */ |
623 | command[1] = 1; /* CONNECT command */ |
624 | |
625 | /* port */ |
626 | command[2] = (char) (p->remote_port >> 8) & 0xff; |
627 | command[3] = (char) p->remote_port & 0xff; |
628 | |
629 | /* address */ |
630 | sk_addrcopy(p->remote_addr, command + 4); |
631 | |
632 | sk_write(p->sub_socket, command, length); |
633 | free(command); |
634 | |
635 | p->state = 1; |
636 | return 0; |
637 | } |
638 | |
639 | if (change == PROXY_CHANGE_CLOSING) { |
640 | /* if our proxy negotiation process involves closing and opening |
641 | * new sockets, then we would want to intercept this closing |
642 | * callback when we were expecting it. if we aren't anticipating |
643 | * a socket close, then some error must have occurred. we'll |
644 | * just pass those errors up to the backend. |
645 | */ |
646 | return plug_closing(p->plug, p->closing_error_msg, |
647 | p->closing_error_code, |
648 | p->closing_calling_back); |
649 | } |
650 | |
651 | if (change == PROXY_CHANGE_SENT) { |
652 | /* some (or all) of what we wrote to the proxy was sent. |
653 | * we don't do anything new, however, until we receive the |
654 | * proxy's response. we might want to set a timer so we can |
655 | * timeout the proxy negotiation after a while... |
656 | */ |
657 | return 0; |
658 | } |
659 | |
660 | if (change == PROXY_CHANGE_ACCEPTING) { |
661 | /* we should _never_ see this, as we are using our socket to |
662 | * connect to a proxy, not accepting inbound connections. |
663 | * what should we do? close the socket with an appropriate |
664 | * error message? |
665 | */ |
666 | return plug_accepting(p->plug, p->accepting_sock); |
667 | } |
668 | |
669 | if (change == PROXY_CHANGE_RECEIVE) { |
670 | /* we have received data from the underlying socket, which |
671 | * we'll need to parse, process, and respond to appropriately. |
672 | */ |
673 | |
674 | if (p->state == 1) { |
675 | /* response format: |
676 | * version number (1 byte) = 4 |
677 | * reply code (1 byte) |
678 | * 90 = request granted |
679 | * 91 = request rejected or failed |
680 | * 92 = request rejected due to lack of IDENTD on client |
681 | * 93 = request rejected due to difference in user ID |
682 | * (what we sent vs. what IDENTD said) |
683 | * dest. port (2 bytes) |
684 | * dest. address (4 bytes) |
685 | */ |
686 | |
7983f47e |
687 | char data[8]; |
6971bbe7 |
688 | |
7983f47e |
689 | if (bufchain_size(&p->pending_input_data) < 8) |
690 | return 1; /* not got anything yet */ |
691 | |
6971bbe7 |
692 | /* get the response */ |
7983f47e |
693 | bufchain_fetch(&p->pending_input_data, data, 8); |
6971bbe7 |
694 | |
695 | if (data[0] != 0) { |
7983f47e |
696 | plug_closing(p->plug, "Proxy error: SOCKS proxy responded with " |
6971bbe7 |
697 | "unexpected reply code version", |
698 | PROXY_ERROR_GENERAL, 0); |
699 | return 1; |
700 | } |
701 | |
702 | if (data[1] != 90) { |
703 | |
704 | switch (data[1]) { |
705 | case 92: |
7983f47e |
706 | plug_closing(p->plug, "Proxy error: SOCKS server wanted IDENTD on client", |
6971bbe7 |
707 | PROXY_ERROR_GENERAL, 0); |
708 | break; |
709 | case 93: |
7983f47e |
710 | plug_closing(p->plug, "Proxy error: Username and IDENTD on client don't agree", |
6971bbe7 |
711 | PROXY_ERROR_GENERAL, 0); |
712 | break; |
713 | case 91: |
714 | default: |
7983f47e |
715 | plug_closing(p->plug, "Proxy error: Error while communicating with proxy", |
6971bbe7 |
716 | PROXY_ERROR_GENERAL, 0); |
717 | break; |
718 | } |
719 | |
720 | return 1; |
721 | } |
7983f47e |
722 | bufchain_consume(&p->pending_input_data, 8); |
6971bbe7 |
723 | |
724 | /* we're done */ |
725 | proxy_activate(p); |
726 | /* proxy activate will have dealt with |
727 | * whatever is left of the buffer */ |
728 | return 1; |
729 | } |
730 | } |
731 | |
7983f47e |
732 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
6971bbe7 |
733 | PROXY_ERROR_UNEXPECTED, 0); |
734 | return 1; |
735 | } |
736 | |
737 | /* SOCKS version 5 */ |
738 | int proxy_socks5_negotiate (Proxy_Socket p, int change) |
739 | { |
740 | if (p->state == PROXY_CHANGE_NEW) { |
741 | |
742 | /* initial command: |
743 | * version number (1 byte) = 5 |
744 | * number of available authentication methods (1 byte) |
745 | * available authentication methods (1 byte * previous value) |
746 | * authentication methods: |
747 | * 0x00 = no authentication |
748 | * 0x01 = GSSAPI |
749 | * 0x02 = username/password |
750 | * 0x03 = CHAP |
751 | */ |
752 | |
aab91a3e |
753 | char command[4]; |
754 | int len; |
6971bbe7 |
755 | |
756 | command[0] = 5; /* version 5 */ |
aab91a3e |
757 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
758 | command[1] = 2; /* two methods supported: */ |
759 | command[2] = 0x00; /* no authentication */ |
760 | command[3] = 0x02; /* username/password */ |
761 | len = 4; |
762 | } else { |
763 | command[1] = 1; /* one methods supported: */ |
764 | command[2] = 0x00; /* no authentication */ |
765 | len = 3; |
766 | } |
6971bbe7 |
767 | |
aab91a3e |
768 | sk_write(p->sub_socket, command, len); |
6971bbe7 |
769 | |
770 | p->state = 1; |
771 | return 0; |
772 | } |
773 | |
774 | if (change == PROXY_CHANGE_CLOSING) { |
775 | /* if our proxy negotiation process involves closing and opening |
776 | * new sockets, then we would want to intercept this closing |
777 | * callback when we were expecting it. if we aren't anticipating |
778 | * a socket close, then some error must have occurred. we'll |
779 | * just pass those errors up to the backend. |
780 | */ |
781 | return plug_closing(p->plug, p->closing_error_msg, |
782 | p->closing_error_code, |
783 | p->closing_calling_back); |
784 | } |
785 | |
786 | if (change == PROXY_CHANGE_SENT) { |
787 | /* some (or all) of what we wrote to the proxy was sent. |
788 | * we don't do anything new, however, until we receive the |
789 | * proxy's response. we might want to set a timer so we can |
790 | * timeout the proxy negotiation after a while... |
791 | */ |
792 | return 0; |
793 | } |
794 | |
795 | if (change == PROXY_CHANGE_ACCEPTING) { |
796 | /* we should _never_ see this, as we are using our socket to |
797 | * connect to a proxy, not accepting inbound connections. |
798 | * what should we do? close the socket with an appropriate |
799 | * error message? |
800 | */ |
801 | return plug_accepting(p->plug, p->accepting_sock); |
802 | } |
803 | |
804 | if (change == PROXY_CHANGE_RECEIVE) { |
805 | /* we have received data from the underlying socket, which |
806 | * we'll need to parse, process, and respond to appropriately. |
807 | */ |
808 | |
6971bbe7 |
809 | if (p->state == 1) { |
810 | |
811 | /* initial response: |
812 | * version number (1 byte) = 5 |
813 | * authentication method (1 byte) |
814 | * authentication methods: |
815 | * 0x00 = no authentication |
816 | * 0x01 = GSSAPI |
817 | * 0x02 = username/password |
818 | * 0x03 = CHAP |
819 | * 0xff = no acceptable methods |
820 | */ |
7983f47e |
821 | char data[2]; |
822 | |
823 | if (bufchain_size(&p->pending_input_data) < 2) |
824 | return 1; /* not got anything yet */ |
6971bbe7 |
825 | |
826 | /* get the response */ |
7983f47e |
827 | bufchain_fetch(&p->pending_input_data, data, 2); |
6971bbe7 |
828 | |
829 | if (data[0] != 5) { |
7983f47e |
830 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned unexpected version", |
6971bbe7 |
831 | PROXY_ERROR_GENERAL, 0); |
832 | return 1; |
833 | } |
834 | |
835 | if (data[1] == 0x00) p->state = 2; /* no authentication needed */ |
836 | else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */ |
837 | else if (data[1] == 0x02) p->state = 5; /* username/password authentication */ |
838 | else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */ |
839 | else { |
7983f47e |
840 | plug_closing(p->plug, "Proxy error: SOCKS proxy did not accept our authentication", |
6971bbe7 |
841 | PROXY_ERROR_GENERAL, 0); |
842 | return 1; |
843 | } |
aab91a3e |
844 | bufchain_consume(&p->pending_input_data, 2); |
845 | } |
846 | |
847 | if (p->state == 7) { |
848 | |
849 | /* password authentication reply format: |
850 | * version number (1 bytes) = 1 |
851 | * reply code (1 byte) |
852 | * 0 = succeeded |
853 | * >0 = failed |
854 | */ |
7983f47e |
855 | char data[2]; |
856 | |
857 | if (bufchain_size(&p->pending_input_data) < 2) |
858 | return 1; /* not got anything yet */ |
aab91a3e |
859 | |
860 | /* get the response */ |
7983f47e |
861 | bufchain_fetch(&p->pending_input_data, data, 2); |
aab91a3e |
862 | |
863 | if (data[0] != 1) { |
7983f47e |
864 | plug_closing(p->plug, "Proxy error: SOCKS password " |
865 | "subnegotiation contained wrong version number", |
aab91a3e |
866 | PROXY_ERROR_GENERAL, 0); |
867 | return 1; |
868 | } |
869 | |
870 | if (data[1] != 0) { |
871 | |
7983f47e |
872 | plug_closing(p->plug, "Proxy error: SOCKS proxy refused" |
873 | " password authentication", |
aab91a3e |
874 | PROXY_ERROR_GENERAL, 0); |
875 | return 1; |
876 | } |
877 | |
878 | bufchain_consume(&p->pending_input_data, 2); |
879 | p->state = 2; /* now proceed as authenticated */ |
6971bbe7 |
880 | } |
881 | |
882 | if (p->state == 2) { |
883 | |
884 | /* request format: |
885 | * version number (1 byte) = 5 |
886 | * command code (1 byte) |
887 | * 1 = CONNECT |
888 | * 2 = BIND |
889 | * 3 = UDP ASSOCIATE |
890 | * reserved (1 byte) = 0x00 |
891 | * address type (1 byte) |
892 | * 1 = IPv4 |
893 | * 3 = domainname (first byte has length, no terminating null) |
894 | * 4 = IPv6 |
895 | * dest. address (variable) |
896 | * dest. port (2 bytes) [network order] |
897 | */ |
898 | |
899 | char command[22]; |
900 | int len; |
901 | |
902 | if (sk_addrtype(p->remote_addr) == AF_INET) { |
903 | len = 10; |
904 | command[3] = 1; /* IPv4 */ |
905 | } else { |
906 | len = 22; |
907 | command[3] = 4; /* IPv6 */ |
908 | } |
909 | |
910 | command[0] = 5; /* version 5 */ |
911 | command[1] = 1; /* CONNECT command */ |
912 | command[2] = 0x00; |
913 | |
914 | /* address */ |
915 | sk_addrcopy(p->remote_addr, command+4); |
916 | |
917 | /* port */ |
918 | command[len-2] = (char) (p->remote_port >> 8) & 0xff; |
919 | command[len-1] = (char) p->remote_port & 0xff; |
920 | |
921 | sk_write(p->sub_socket, command, len); |
922 | |
923 | p->state = 3; |
924 | return 1; |
925 | } |
926 | |
927 | if (p->state == 3) { |
928 | |
929 | /* reply format: |
930 | * version number (1 bytes) = 5 |
931 | * reply code (1 byte) |
932 | * 0 = succeeded |
933 | * 1 = general SOCKS server failure |
934 | * 2 = connection not allowed by ruleset |
935 | * 3 = network unreachable |
936 | * 4 = host unreachable |
937 | * 5 = connection refused |
938 | * 6 = TTL expired |
939 | * 7 = command not supported |
940 | * 8 = address type not supported |
941 | * reserved (1 byte) = x00 |
942 | * address type (1 byte) |
943 | * 1 = IPv4 |
944 | * 3 = domainname (first byte has length, no terminating null) |
945 | * 4 = IPv6 |
946 | * server bound address (variable) |
947 | * server bound port (2 bytes) [network order] |
948 | */ |
7983f47e |
949 | char data[5]; |
950 | int len; |
951 | |
952 | /* First 5 bytes of packet are enough to tell its length. */ |
953 | if (bufchain_size(&p->pending_input_data) < 5) |
954 | return 1; /* not got anything yet */ |
6971bbe7 |
955 | |
956 | /* get the response */ |
7983f47e |
957 | bufchain_fetch(&p->pending_input_data, data, 5); |
6971bbe7 |
958 | |
959 | if (data[0] != 5) { |
7983f47e |
960 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned wrong version number", |
6971bbe7 |
961 | PROXY_ERROR_GENERAL, 0); |
962 | return 1; |
963 | } |
964 | |
965 | if (data[1] != 0) { |
7983f47e |
966 | char buf[256]; |
967 | |
968 | strcpy(buf, "Proxy error: "); |
6971bbe7 |
969 | |
970 | switch (data[1]) { |
7983f47e |
971 | case 1: strcat(buf, "General SOCKS server failure"); break; |
972 | case 2: strcat(buf, "Connection not allowed by ruleset"); break; |
973 | case 3: strcat(buf, "Network unreachable"); break; |
974 | case 4: strcat(buf, "Host unreachable"); break; |
975 | case 5: strcat(buf, "Connection refused"); break; |
976 | case 6: strcat(buf, "TTL expired"); break; |
977 | case 7: strcat(buf, "Command not supported"); break; |
978 | case 8: strcat(buf, "Address type not supported"); break; |
979 | default: sprintf(buf+strlen(buf), |
980 | "Unrecognised SOCKS error code %d", |
981 | data[1]); |
6971bbe7 |
982 | break; |
983 | } |
7983f47e |
984 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
985 | |
986 | return 1; |
987 | } |
6971bbe7 |
988 | |
7983f47e |
989 | /* |
990 | * Eat the rest of the reply packet. |
991 | */ |
992 | len = 6; /* first 4 bytes, last 2 */ |
993 | switch (data[3]) { |
994 | case 1: len += 4; break; /* IPv4 address */ |
995 | case 4: len += 16; break;/* IPv6 address */ |
996 | case 3: len += (unsigned char)data[4]; break; /* domain name */ |
997 | default: |
998 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned " |
999 | "unrecognised address format", |
1000 | PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
1001 | return 1; |
1002 | } |
7983f47e |
1003 | if (bufchain_size(&p->pending_input_data) < len) |
1004 | return 1; /* not got whole reply yet */ |
1005 | bufchain_consume(&p->pending_input_data, len); |
6971bbe7 |
1006 | |
1007 | /* we're done */ |
1008 | proxy_activate(p); |
6971bbe7 |
1009 | return 1; |
1010 | } |
1011 | |
1012 | if (p->state == 4) { |
1013 | /* TODO: Handle GSSAPI authentication */ |
2192a8e4 |
1014 | plug_closing(p->plug, "Proxy error: We don't support GSSAPI authentication", |
6971bbe7 |
1015 | PROXY_ERROR_GENERAL, 0); |
1016 | return 1; |
1017 | } |
1018 | |
1019 | if (p->state == 5) { |
aab91a3e |
1020 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
1021 | char userpwbuf[514]; |
1022 | int ulen, plen; |
1023 | ulen = strlen(cfg.proxy_username); |
1024 | if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1; |
1025 | plen = strlen(cfg.proxy_password); |
1026 | if (plen > 255) plen = 255; if (plen < 1) plen = 1; |
1027 | userpwbuf[0] = 1; /* version number of subnegotiation */ |
1028 | userpwbuf[1] = ulen; |
1029 | memcpy(userpwbuf+2, cfg.proxy_username, ulen); |
1030 | userpwbuf[ulen+2] = plen; |
1031 | memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen); |
1032 | sk_write(p->sub_socket, userpwbuf, ulen + plen + 3); |
1033 | p->state = 7; |
1034 | } else |
2192a8e4 |
1035 | plug_closing(p->plug, "Proxy error: Server chose " |
aab91a3e |
1036 | "username/password authentication but we " |
1037 | "didn't offer it!", |
6971bbe7 |
1038 | PROXY_ERROR_GENERAL, 0); |
1039 | return 1; |
1040 | } |
1041 | |
1042 | if (p->state == 6) { |
1043 | /* TODO: Handle CHAP authentication */ |
2192a8e4 |
1044 | plug_closing(p->plug, "Proxy error: We don't support CHAP authentication", |
6971bbe7 |
1045 | PROXY_ERROR_GENERAL, 0); |
1046 | return 1; |
1047 | } |
aab91a3e |
1048 | |
6971bbe7 |
1049 | } |
1050 | |
2192a8e4 |
1051 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
6971bbe7 |
1052 | PROXY_ERROR_UNEXPECTED, 0); |
1053 | return 1; |
8eebd221 |
1054 | } |
1055 | |
1056 | /* ---------------------------------------------------------------------- |
0e8f4cda |
1057 | * `Telnet' proxy type. |
8eebd221 |
1058 | * |
1059 | * (This is for ad-hoc proxies where you connect to the proxy's |
1060 | * telnet port and send a command such as `connect host port'. The |
1061 | * command is configurable, since this proxy type is typically not |
1062 | * standardised or at all well-defined.) |
1063 | */ |
1064 | |
1065 | int proxy_telnet_negotiate (Proxy_Socket p, int change) |
1066 | { |
0e8f4cda |
1067 | if (p->state == PROXY_CHANGE_NEW) { |
1068 | |
1069 | int so = 0, eo = 0; |
1070 | |
1071 | /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, |
1072 | * %%, %host, and %port |
1073 | */ |
1074 | |
1075 | while (cfg.proxy_telnet_command[eo] != 0) { |
1076 | |
1077 | /* scan forward until we hit end-of-line, |
1078 | * or an escape character (\ or %) */ |
1079 | while (cfg.proxy_telnet_command[eo] != 0 && |
1080 | cfg.proxy_telnet_command[eo] != '%' && |
1081 | cfg.proxy_telnet_command[eo] != '\\') eo++; |
1082 | |
1083 | /* if we hit eol, break out of our escaping loop */ |
1084 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1085 | |
1086 | /* if there was any unescaped text before the escape |
1087 | * character, send that now */ |
1088 | if (eo != so) { |
1089 | sk_write(p->sub_socket, |
1090 | cfg.proxy_telnet_command + so, eo - so); |
1091 | } |
1092 | |
1093 | so = eo++; |
1094 | |
1095 | /* if the escape character was the last character of |
1096 | * the line, we'll just stop and send it. */ |
1097 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1098 | |
1099 | if (cfg.proxy_telnet_command[so] == '\\') { |
1100 | |
1101 | /* we recognize \\, \%, \r, \n, \t, \x??. |
1102 | * anything else, we just send unescaped (including the \). |
1103 | */ |
1104 | |
1105 | switch (cfg.proxy_telnet_command[eo]) { |
1106 | |
1107 | case '\\': |
1108 | sk_write(p->sub_socket, "\\", 1); |
1109 | eo++; |
1110 | break; |
1111 | |
1112 | case '%': |
1113 | sk_write(p->sub_socket, "%%", 1); |
1114 | eo++; |
1115 | break; |
1116 | |
1117 | case 'r': |
1118 | sk_write(p->sub_socket, "\r", 1); |
1119 | eo++; |
1120 | break; |
1121 | |
1122 | case 'n': |
1123 | sk_write(p->sub_socket, "\n", 1); |
1124 | eo++; |
1125 | break; |
1126 | |
1127 | case 't': |
1128 | sk_write(p->sub_socket, "\t", 1); |
1129 | eo++; |
1130 | break; |
1131 | |
1132 | case 'x': |
1133 | case 'X': |
1134 | { |
1135 | /* escaped hexadecimal value (ie. \xff) */ |
1136 | unsigned char v = 0; |
1137 | int i = 0; |
1138 | |
1139 | for (;;) { |
1140 | eo++; |
1141 | if (cfg.proxy_telnet_command[eo] >= '0' && |
1142 | cfg.proxy_telnet_command[eo] <= '9') |
1143 | v += cfg.proxy_telnet_command[eo] - '0'; |
1144 | else if (cfg.proxy_telnet_command[eo] >= 'a' && |
1145 | cfg.proxy_telnet_command[eo] <= 'f') |
1146 | v += cfg.proxy_telnet_command[eo] - 'a' + 10; |
1147 | else if (cfg.proxy_telnet_command[eo] >= 'A' && |
1148 | cfg.proxy_telnet_command[eo] <= 'F') |
1149 | v += cfg.proxy_telnet_command[eo] - 'A' + 10; |
1150 | else { |
1151 | /* non hex character, so we abort and just |
1152 | * send the whole thing unescaped (including \x) |
1153 | */ |
1154 | sk_write(p->sub_socket, "\\", 1); |
1155 | eo = so + 1; |
1156 | break; |
1157 | } |
1158 | |
1159 | /* we only extract two hex characters */ |
1160 | if (i == 1) { |
1161 | sk_write(p->sub_socket, &v, 1); |
1162 | eo++; |
1163 | break; |
1164 | } |
1165 | |
1166 | i++; |
1167 | v <<= 4; |
1168 | } |
1169 | } |
1170 | break; |
1171 | |
1172 | default: |
1173 | sk_write(p->sub_socket, |
1174 | cfg.proxy_telnet_command + so, 2); |
1175 | eo++; |
1176 | break; |
1177 | } |
1178 | } else { |
1179 | |
1180 | /* % escape. we recognize %%, %host, %port. anything else, |
1181 | * we just send unescaped (including the %). */ |
1182 | |
1183 | if (cfg.proxy_telnet_command[eo] == '%') { |
1184 | sk_write(p->sub_socket, "%", 1); |
1185 | eo++; |
1186 | } |
1187 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1188 | "host", 4) == 0) { |
1189 | char dest[64]; |
1190 | sk_getaddr(p->remote_addr, dest, 64); |
1191 | sk_write(p->sub_socket, dest, strlen(dest)); |
1192 | eo += 4; |
1193 | } |
1194 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1195 | "port", 4) == 0) { |
1196 | char port[8]; |
1197 | sprintf(port, "%i", p->remote_port); |
1198 | sk_write(p->sub_socket, port, strlen(port)); |
1199 | eo += 4; |
1200 | } |
1201 | else { |
1202 | /* we don't escape this, so send the % now, and |
1203 | * don't advance eo, so that we'll consider the |
1204 | * text immediately following the % as unescaped. |
1205 | */ |
1206 | sk_write(p->sub_socket, "%", 1); |
1207 | } |
1208 | } |
1209 | |
1210 | /* resume scanning for additional escapes after this one. */ |
1211 | so = eo; |
1212 | } |
1213 | |
1214 | /* if there is any unescaped text at the end of the line, send it */ |
1215 | if (eo != so) { |
1216 | sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); |
1217 | } |
1218 | |
1219 | p->state = 1; |
0e8f4cda |
1220 | return 0; |
1221 | } |
1222 | |
1223 | if (change == PROXY_CHANGE_CLOSING) { |
1224 | /* if our proxy negotiation process involves closing and opening |
1225 | * new sockets, then we would want to intercept this closing |
1226 | * callback when we were expecting it. if we aren't anticipating |
1227 | * a socket close, then some error must have occurred. we'll |
1228 | * just pass those errors up to the backend. |
1229 | */ |
1230 | return plug_closing(p->plug, p->closing_error_msg, |
1231 | p->closing_error_code, |
1232 | p->closing_calling_back); |
1233 | } |
1234 | |
1235 | if (change == PROXY_CHANGE_SENT) { |
1236 | /* some (or all) of what we wrote to the proxy was sent. |
1237 | * we don't do anything new, however, until we receive the |
1238 | * proxy's response. we might want to set a timer so we can |
1239 | * timeout the proxy negotiation after a while... |
1240 | */ |
1241 | return 0; |
1242 | } |
1243 | |
1244 | if (change == PROXY_CHANGE_ACCEPTING) { |
1245 | /* we should _never_ see this, as we are using our socket to |
1246 | * connect to a proxy, not accepting inbound connections. |
1247 | * what should we do? close the socket with an appropriate |
1248 | * error message? |
1249 | */ |
1250 | return plug_accepting(p->plug, p->accepting_sock); |
1251 | } |
1252 | |
1253 | if (change == PROXY_CHANGE_RECEIVE) { |
1254 | /* we have received data from the underlying socket, which |
1255 | * we'll need to parse, process, and respond to appropriately. |
1256 | */ |
1257 | |
1258 | /* we're done */ |
1259 | proxy_activate(p); |
1260 | /* proxy activate will have dealt with |
1261 | * whatever is left of the buffer */ |
1262 | return 1; |
1263 | } |
1264 | |
2192a8e4 |
1265 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
0e8f4cda |
1266 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
1267 | return 1; |
8eebd221 |
1268 | } |