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> |
de9aaffb |
11 | #include <ctype.h> |
12 | #include <string.h> |
7983f47e |
13 | |
8eebd221 |
14 | #define DEFINE_PLUG_METHOD_MACROS |
15 | #include "putty.h" |
16 | #include "network.h" |
17 | #include "proxy.h" |
18 | |
19 | /* |
20 | * Call this when proxy negotiation is complete, so that this |
21 | * socket can begin working normally. |
22 | */ |
23 | void proxy_activate (Proxy_Socket p) |
24 | { |
25 | void *data; |
26 | int len; |
2d129d8e |
27 | long output_before, output_after; |
28 | |
8eebd221 |
29 | p->state = PROXY_STATE_ACTIVE; |
30 | |
2d129d8e |
31 | /* we want to ignore new receive events until we have sent |
32 | * all of our buffered receive data. |
33 | */ |
8eebd221 |
34 | sk_set_frozen(p->sub_socket, 1); |
35 | |
2d129d8e |
36 | /* how many bytes of output have we buffered? */ |
37 | output_before = bufchain_size(&p->pending_oob_output_data) + |
38 | bufchain_size(&p->pending_output_data); |
39 | /* and keep track of how many bytes do not get sent. */ |
40 | output_after = 0; |
41 | |
0e8f4cda |
42 | /* send buffered OOB writes */ |
8eebd221 |
43 | while (bufchain_size(&p->pending_oob_output_data) > 0) { |
44 | bufchain_prefix(&p->pending_oob_output_data, &data, &len); |
2d129d8e |
45 | output_after += sk_write_oob(p->sub_socket, data, len); |
8eebd221 |
46 | bufchain_consume(&p->pending_oob_output_data, len); |
47 | } |
8eebd221 |
48 | |
0e8f4cda |
49 | /* send buffered normal writes */ |
8eebd221 |
50 | while (bufchain_size(&p->pending_output_data) > 0) { |
51 | bufchain_prefix(&p->pending_output_data, &data, &len); |
2d129d8e |
52 | output_after += sk_write(p->sub_socket, data, len); |
8eebd221 |
53 | bufchain_consume(&p->pending_output_data, len); |
54 | } |
2d129d8e |
55 | |
56 | /* if we managed to send any data, let the higher levels know. */ |
57 | if (output_after < output_before) |
58 | plug_sent(p->plug, output_after); |
8eebd221 |
59 | |
0e8f4cda |
60 | /* if we were asked to flush the output during |
61 | * the proxy negotiation process, do so now. |
62 | */ |
8eebd221 |
63 | if (p->pending_flush) sk_flush(p->sub_socket); |
8eebd221 |
64 | |
2d129d8e |
65 | /* if the backend wanted the socket unfrozen, try to unfreeze. |
66 | * our set_frozen handler will flush buffered receive data before |
67 | * unfreezing the actual underlying socket. |
68 | */ |
69 | if (!p->freeze) |
70 | sk_set_frozen((Socket)p, 0); |
8eebd221 |
71 | } |
72 | |
73 | /* basic proxy socket functions */ |
74 | |
75 | static Plug sk_proxy_plug (Socket s, Plug p) |
76 | { |
77 | Proxy_Socket ps = (Proxy_Socket) s; |
78 | Plug ret = ps->plug; |
79 | if (p) |
80 | ps->plug = p; |
81 | return ret; |
82 | } |
83 | |
84 | static void sk_proxy_close (Socket s) |
85 | { |
86 | Proxy_Socket ps = (Proxy_Socket) s; |
87 | |
8eebd221 |
88 | sk_close(ps->sub_socket); |
89 | sfree(ps); |
90 | } |
91 | |
92 | static int sk_proxy_write (Socket s, char *data, int len) |
93 | { |
94 | Proxy_Socket ps = (Proxy_Socket) s; |
95 | |
8eebd221 |
96 | if (ps->state != PROXY_STATE_ACTIVE) { |
97 | bufchain_add(&ps->pending_output_data, data, len); |
98 | return bufchain_size(&ps->pending_output_data); |
99 | } |
100 | return sk_write(ps->sub_socket, data, len); |
101 | } |
102 | |
103 | static int sk_proxy_write_oob (Socket s, char *data, int len) |
104 | { |
105 | Proxy_Socket ps = (Proxy_Socket) s; |
106 | |
8eebd221 |
107 | if (ps->state != PROXY_STATE_ACTIVE) { |
108 | bufchain_clear(&ps->pending_output_data); |
109 | bufchain_clear(&ps->pending_oob_output_data); |
110 | bufchain_add(&ps->pending_oob_output_data, data, len); |
111 | return len; |
112 | } |
113 | return sk_write_oob(ps->sub_socket, data, len); |
114 | } |
115 | |
116 | static void sk_proxy_flush (Socket s) |
117 | { |
118 | Proxy_Socket ps = (Proxy_Socket) s; |
119 | |
8eebd221 |
120 | if (ps->state != PROXY_STATE_ACTIVE) { |
121 | ps->pending_flush = 1; |
122 | return; |
123 | } |
124 | sk_flush(ps->sub_socket); |
125 | } |
126 | |
127 | static void sk_proxy_set_private_ptr (Socket s, void *ptr) |
128 | { |
129 | Proxy_Socket ps = (Proxy_Socket) s; |
130 | sk_set_private_ptr(ps->sub_socket, ptr); |
131 | } |
132 | |
133 | static void * sk_proxy_get_private_ptr (Socket s) |
134 | { |
135 | Proxy_Socket ps = (Proxy_Socket) s; |
136 | return sk_get_private_ptr(ps->sub_socket); |
137 | } |
138 | |
139 | static void sk_proxy_set_frozen (Socket s, int is_frozen) |
140 | { |
141 | Proxy_Socket ps = (Proxy_Socket) s; |
142 | |
8eebd221 |
143 | if (ps->state != PROXY_STATE_ACTIVE) { |
144 | ps->freeze = is_frozen; |
145 | return; |
146 | } |
2d129d8e |
147 | |
148 | /* handle any remaining buffered recv data first */ |
149 | if (bufchain_size(&ps->pending_input_data) > 0) { |
150 | ps->freeze = is_frozen; |
151 | |
152 | /* loop while we still have buffered data, and while we are |
153 | * unfrozen. the plug_receive call in the loop could result |
154 | * in a call back into this function refreezing the socket, |
155 | * so we have to check each time. |
156 | */ |
157 | while (!ps->freeze && bufchain_size(&ps->pending_input_data) > 0) { |
158 | char * data; |
159 | int len; |
160 | bufchain_prefix(&ps->pending_input_data, &data, &len); |
161 | plug_receive(ps->plug, 0, data, len); |
162 | bufchain_consume(&ps->pending_input_data, len); |
163 | } |
164 | |
165 | /* if we're still frozen, we'll have to wait for another |
166 | * call from the backend to finish unbuffering the data. |
167 | */ |
168 | if (ps->freeze) return; |
169 | } |
170 | |
8eebd221 |
171 | sk_set_frozen(ps->sub_socket, is_frozen); |
172 | } |
173 | |
174 | static char * sk_proxy_socket_error (Socket s) |
175 | { |
176 | Proxy_Socket ps = (Proxy_Socket) s; |
177 | if (ps->error != NULL || ps->sub_socket == NULL) { |
178 | return ps->error; |
179 | } |
180 | return sk_socket_error(ps->sub_socket); |
181 | } |
182 | |
183 | /* basic proxy plug functions */ |
184 | |
185 | static int plug_proxy_closing (Plug p, char *error_msg, |
186 | int error_code, int calling_back) |
187 | { |
188 | Proxy_Plug pp = (Proxy_Plug) p; |
189 | Proxy_Socket ps = pp->proxy_socket; |
190 | |
8eebd221 |
191 | if (ps->state != PROXY_STATE_ACTIVE) { |
192 | ps->closing_error_msg = error_msg; |
193 | ps->closing_error_code = error_code; |
194 | ps->closing_calling_back = calling_back; |
195 | return ps->negotiate(ps, PROXY_CHANGE_CLOSING); |
196 | } |
197 | return plug_closing(ps->plug, error_msg, |
198 | error_code, calling_back); |
199 | } |
200 | |
201 | static int plug_proxy_receive (Plug p, int urgent, char *data, int len) |
202 | { |
203 | Proxy_Plug pp = (Proxy_Plug) p; |
204 | Proxy_Socket ps = pp->proxy_socket; |
205 | |
8eebd221 |
206 | if (ps->state != PROXY_STATE_ACTIVE) { |
207 | /* we will lose the urgentness of this data, but since most, |
208 | * if not all, of this data will be consumed by the negotiation |
209 | * process, hopefully it won't affect the protocol above us |
210 | */ |
211 | bufchain_add(&ps->pending_input_data, data, len); |
212 | ps->receive_urgent = urgent; |
213 | ps->receive_data = data; |
214 | ps->receive_len = len; |
215 | return ps->negotiate(ps, PROXY_CHANGE_RECEIVE); |
216 | } |
217 | return plug_receive(ps->plug, urgent, data, len); |
218 | } |
219 | |
220 | static void plug_proxy_sent (Plug p, int bufsize) |
221 | { |
222 | Proxy_Plug pp = (Proxy_Plug) p; |
223 | Proxy_Socket ps = pp->proxy_socket; |
224 | |
8eebd221 |
225 | if (ps->state != PROXY_STATE_ACTIVE) { |
226 | ps->sent_bufsize = bufsize; |
227 | ps->negotiate(ps, PROXY_CHANGE_SENT); |
228 | return; |
229 | } |
230 | plug_sent(ps->plug, bufsize); |
231 | } |
232 | |
233 | static int plug_proxy_accepting (Plug p, void *sock) |
234 | { |
235 | Proxy_Plug pp = (Proxy_Plug) p; |
236 | Proxy_Socket ps = pp->proxy_socket; |
237 | |
8eebd221 |
238 | if (ps->state != PROXY_STATE_ACTIVE) { |
239 | ps->accepting_sock = sock; |
240 | return ps->negotiate(ps, PROXY_CHANGE_ACCEPTING); |
241 | } |
242 | return plug_accepting(ps->plug, sock); |
243 | } |
244 | |
245 | static int proxy_for_destination (SockAddr addr, char * hostname, int port) |
246 | { |
247 | int s = 0, e = 0; |
248 | char hostip[64]; |
249 | int hostip_len, hostname_len; |
250 | char * exclude_list; |
251 | |
252 | /* we want a string representation of the IP address for comparisons */ |
253 | sk_getaddr(addr, hostip, 64); |
254 | |
255 | hostip_len = strlen(hostip); |
256 | hostname_len = strlen(hostname); |
257 | |
258 | exclude_list = cfg.proxy_exclude_list; |
259 | |
260 | /* now parse the exclude list, and see if either our IP |
261 | * or hostname matches anything in it. |
262 | */ |
263 | |
264 | while (exclude_list[s]) { |
265 | while (exclude_list[s] && |
266 | (isspace(exclude_list[s]) || |
267 | exclude_list[s] == ',')) s++; |
268 | |
269 | if (!exclude_list[s]) break; |
270 | |
271 | e = s; |
272 | |
273 | while (exclude_list[e] && |
274 | (isalnum(exclude_list[e]) || |
275 | exclude_list[e] == '-' || |
276 | exclude_list[e] == '.' || |
277 | exclude_list[e] == '*')) e++; |
278 | |
279 | if (exclude_list[s] == '*') { |
280 | /* wildcard at beginning of entry */ |
281 | |
282 | if (strnicmp(hostip + hostip_len - (e - s - 1), |
283 | exclude_list + s + 1, e - s - 1) == 0 || |
284 | strnicmp(hostname + hostname_len - (e - s - 1), |
285 | exclude_list + s + 1, e - s - 1) == 0) |
286 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
287 | |
288 | } else if (exclude_list[e-1] == '*') { |
289 | /* wildcard at end of entry */ |
290 | |
291 | if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 || |
292 | strnicmp(hostname, exclude_list + s, e - s - 1) == 0) |
293 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
294 | |
295 | } else { |
296 | /* no wildcard at either end, so let's try an absolute |
297 | * match (ie. a specific IP) |
298 | */ |
299 | |
300 | if (stricmp(hostip, exclude_list + s) == 0) |
301 | return 0; /* IP/hostname excluded. do not use proxy. */ |
302 | if (stricmp(hostname, exclude_list + s) == 0) |
303 | return 0; /* IP/hostname excluded. do not use proxy. */ |
304 | } |
305 | |
306 | s = e; |
307 | } |
308 | |
309 | /* no matches in the exclude list, so use the proxy */ |
310 | return 1; |
311 | } |
312 | |
313 | Socket new_connection(SockAddr addr, char *hostname, |
314 | int port, int privport, |
315 | int oobinline, int nodelay, Plug plug) |
316 | { |
317 | static struct socket_function_table socket_fn_table = { |
318 | sk_proxy_plug, |
319 | sk_proxy_close, |
320 | sk_proxy_write, |
321 | sk_proxy_write_oob, |
322 | sk_proxy_flush, |
323 | sk_proxy_set_private_ptr, |
324 | sk_proxy_get_private_ptr, |
325 | sk_proxy_set_frozen, |
326 | sk_proxy_socket_error |
327 | }; |
328 | |
329 | static struct plug_function_table plug_fn_table = { |
330 | plug_proxy_closing, |
331 | plug_proxy_receive, |
332 | plug_proxy_sent, |
333 | plug_proxy_accepting |
334 | }; |
335 | |
336 | if (cfg.proxy_type != PROXY_NONE && |
337 | proxy_for_destination(addr, hostname, port)) |
338 | { |
339 | Proxy_Socket ret; |
340 | Proxy_Plug pplug; |
341 | SockAddr proxy_addr; |
342 | char * proxy_canonical_name; |
343 | |
344 | ret = smalloc(sizeof(struct Socket_proxy_tag)); |
345 | ret->fn = &socket_fn_table; |
346 | ret->plug = plug; |
347 | ret->remote_addr = addr; |
348 | ret->remote_port = port; |
349 | |
65c78e88 |
350 | ret->error = NULL; |
351 | ret->pending_flush = 0; |
352 | ret->freeze = 0; |
353 | |
8eebd221 |
354 | bufchain_init(&ret->pending_input_data); |
355 | bufchain_init(&ret->pending_output_data); |
356 | bufchain_init(&ret->pending_oob_output_data); |
357 | |
8eebd221 |
358 | ret->sub_socket = NULL; |
359 | ret->state = PROXY_STATE_NEW; |
2d129d8e |
360 | ret->negotiate = NULL; |
361 | |
8eebd221 |
362 | if (cfg.proxy_type == PROXY_HTTP) { |
363 | ret->negotiate = proxy_http_negotiate; |
364 | } else if (cfg.proxy_type == PROXY_SOCKS) { |
6971bbe7 |
365 | if (cfg.proxy_socks_version == 4) |
366 | ret->negotiate = proxy_socks4_negotiate; |
367 | else |
368 | ret->negotiate = proxy_socks5_negotiate; |
8eebd221 |
369 | } else if (cfg.proxy_type == PROXY_TELNET) { |
370 | ret->negotiate = proxy_telnet_negotiate; |
371 | } else { |
7983f47e |
372 | ret->error = "Proxy error: Unknown proxy method"; |
8eebd221 |
373 | return (Socket) ret; |
374 | } |
375 | |
376 | /* create the proxy plug to map calls from the actual |
377 | * socket into our proxy socket layer */ |
378 | pplug = smalloc(sizeof(struct Plug_proxy_tag)); |
379 | pplug->fn = &plug_fn_table; |
380 | pplug->proxy_socket = ret; |
381 | |
382 | /* look-up proxy */ |
383 | proxy_addr = sk_namelookup(cfg.proxy_host, |
384 | &proxy_canonical_name); |
385 | sfree(proxy_canonical_name); |
386 | |
387 | /* create the actual socket we will be using, |
388 | * connected to our proxy server and port. |
389 | */ |
390 | ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port, |
391 | privport, oobinline, |
392 | nodelay, (Plug) pplug); |
393 | if (sk_socket_error(ret->sub_socket) != NULL) |
394 | return (Socket) ret; |
395 | |
396 | sk_addr_free(proxy_addr); |
397 | |
398 | /* start the proxy negotiation process... */ |
399 | sk_set_frozen(ret->sub_socket, 0); |
400 | ret->negotiate(ret, PROXY_CHANGE_NEW); |
401 | |
402 | return (Socket) ret; |
403 | } |
404 | |
405 | /* no proxy, so just return the direct socket */ |
406 | return sk_new(addr, port, privport, oobinline, nodelay, plug); |
407 | } |
408 | |
409 | Socket new_listener(int port, Plug plug, int local_host_only) |
410 | { |
411 | /* TODO: SOCKS (and potentially others) support inbound |
412 | * TODO: connections via the proxy. support them. |
413 | */ |
414 | |
415 | return sk_newlistener(port, plug, local_host_only); |
416 | } |
417 | |
418 | /* ---------------------------------------------------------------------- |
419 | * HTTP CONNECT proxy type. |
420 | */ |
421 | |
422 | static int get_line_end (char * data, int len) |
423 | { |
424 | int off = 0; |
425 | |
426 | while (off < len) |
427 | { |
428 | if (data[off] == '\n') { |
429 | /* we have a newline */ |
430 | off++; |
431 | |
432 | /* is that the only thing on this line? */ |
433 | if (off <= 2) return off; |
434 | |
435 | /* if not, then there is the possibility that this header |
436 | * continues onto the next line, if it starts with a space |
437 | * or a tab. |
438 | */ |
439 | |
440 | if (off + 1 < len && |
441 | data[off+1] != ' ' && |
442 | data[off+1] != '\t') return off; |
443 | |
444 | /* the line does continue, so we have to keep going |
445 | * until we see an the header's "real" end of line. |
446 | */ |
447 | off++; |
448 | } |
449 | |
450 | off++; |
451 | } |
452 | |
453 | return -1; |
454 | } |
455 | |
456 | int proxy_http_negotiate (Proxy_Socket p, int change) |
457 | { |
458 | if (p->state == PROXY_STATE_NEW) { |
459 | /* we are just beginning the proxy negotiate process, |
460 | * so we'll send off the initial bits of the request. |
461 | * for this proxy method, it's just a simple HTTP |
462 | * request |
463 | */ |
0e8f4cda |
464 | char buf[256], dest[64]; |
8eebd221 |
465 | |
0e8f4cda |
466 | sk_getaddr(p->remote_addr, dest, 64); |
8eebd221 |
467 | |
1549e076 |
468 | sprintf(buf, "CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n", |
8eebd221 |
469 | dest, p->remote_port, dest, p->remote_port); |
470 | sk_write(p->sub_socket, buf, strlen(buf)); |
471 | |
1549e076 |
472 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
473 | char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)]; |
474 | char buf2[sizeof(buf)*4/3 + 100]; |
475 | int i, j, len; |
476 | sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password); |
477 | len = strlen(buf); |
478 | sprintf(buf2, "Proxy-Authorization: basic "); |
479 | for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4) |
480 | base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j); |
481 | strcpy(buf2+j, "\r\n"); |
482 | sk_write(p->sub_socket, buf2, strlen(buf2)); |
483 | } |
484 | |
485 | sprintf(buf, "\r\n"); |
486 | sk_write(p->sub_socket, buf, strlen(buf)); |
487 | |
8eebd221 |
488 | p->state = 1; |
8eebd221 |
489 | return 0; |
490 | } |
491 | |
492 | if (change == PROXY_CHANGE_CLOSING) { |
493 | /* if our proxy negotiation process involves closing and opening |
494 | * new sockets, then we would want to intercept this closing |
495 | * callback when we were expecting it. if we aren't anticipating |
496 | * a socket close, then some error must have occurred. we'll |
497 | * just pass those errors up to the backend. |
498 | */ |
499 | return plug_closing(p->plug, p->closing_error_msg, |
500 | p->closing_error_code, |
501 | p->closing_calling_back); |
502 | } |
503 | |
504 | if (change == PROXY_CHANGE_SENT) { |
505 | /* some (or all) of what we wrote to the proxy was sent. |
506 | * we don't do anything new, however, until we receive the |
507 | * proxy's response. we might want to set a timer so we can |
508 | * timeout the proxy negotiation after a while... |
509 | */ |
510 | return 0; |
511 | } |
512 | |
513 | if (change == PROXY_CHANGE_ACCEPTING) { |
514 | /* we should _never_ see this, as we are using our socket to |
515 | * connect to a proxy, not accepting inbound connections. |
516 | * what should we do? close the socket with an appropriate |
517 | * error message? |
518 | */ |
519 | return plug_accepting(p->plug, p->accepting_sock); |
520 | } |
521 | |
522 | if (change == PROXY_CHANGE_RECEIVE) { |
523 | /* we have received data from the underlying socket, which |
524 | * we'll need to parse, process, and respond to appropriately. |
525 | */ |
526 | |
7983f47e |
527 | char *data, *datap; |
8eebd221 |
528 | int len; |
529 | int eol; |
530 | |
531 | if (p->state == 1) { |
532 | |
533 | int min_ver, maj_ver, status; |
534 | |
535 | /* get the status line */ |
7983f47e |
536 | len = bufchain_size(&p->pending_input_data); |
537 | assert(len > 0); /* or we wouldn't be here */ |
538 | data = smalloc(len); |
539 | bufchain_fetch(&p->pending_input_data, data, len); |
540 | |
8eebd221 |
541 | eol = get_line_end(data, len); |
7983f47e |
542 | if (eol < 0) { |
543 | sfree(data); |
544 | return 1; |
545 | } |
8eebd221 |
546 | |
7983f47e |
547 | status = -1; |
548 | /* We can't rely on whether the %n incremented the sscanf return */ |
549 | if (sscanf((char *)data, "HTTP/%i.%i %n", |
550 | &maj_ver, &min_ver, &status) < 2 || status == -1) { |
551 | plug_closing(p->plug, "Proxy error: HTTP response was absent", |
552 | PROXY_ERROR_GENERAL, 0); |
553 | sfree(data); |
554 | return 1; |
555 | } |
8eebd221 |
556 | |
557 | /* remove the status line from the input buffer. */ |
558 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
559 | if (data[status] != '2') { |
8eebd221 |
560 | /* error */ |
7983f47e |
561 | char buf[1024]; |
562 | data[eol] = '\0'; |
563 | while (eol > status && |
564 | (data[eol-1] == '\r' || data[eol-1] == '\n')) |
565 | data[--eol] = '\0'; |
566 | sprintf(buf, "Proxy error: %.900s", |
567 | data+status); |
568 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
569 | sfree(data); |
8eebd221 |
570 | return 1; |
571 | } |
572 | |
7983f47e |
573 | sfree(data); |
574 | |
8eebd221 |
575 | p->state = 2; |
576 | } |
577 | |
578 | if (p->state == 2) { |
579 | |
580 | /* get headers. we're done when we get a |
581 | * header of length 2, (ie. just "\r\n") |
582 | */ |
583 | |
7983f47e |
584 | len = bufchain_size(&p->pending_input_data); |
585 | assert(len > 0); /* or we wouldn't be here */ |
586 | data = smalloc(len); |
587 | datap = data; |
588 | bufchain_fetch(&p->pending_input_data, data, len); |
589 | |
590 | eol = get_line_end(datap, len); |
591 | if (eol < 0) { |
592 | sfree(data); |
593 | return 1; |
594 | } |
8eebd221 |
595 | while (eol > 2) |
596 | { |
8eebd221 |
597 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
598 | datap += eol; |
599 | eol = get_line_end(datap, len); |
8eebd221 |
600 | } |
601 | |
602 | if (eol == 2) { |
603 | /* we're done */ |
604 | bufchain_consume(&p->pending_input_data, 2); |
605 | proxy_activate(p); |
606 | /* proxy activate will have dealt with |
607 | * whatever is left of the buffer */ |
7983f47e |
608 | sfree(data); |
8eebd221 |
609 | return 1; |
610 | } |
611 | |
7983f47e |
612 | sfree(data); |
8eebd221 |
613 | return 1; |
614 | } |
615 | } |
616 | |
7983f47e |
617 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
8eebd221 |
618 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
619 | return 1; |
8eebd221 |
620 | } |
621 | |
622 | /* ---------------------------------------------------------------------- |
6971bbe7 |
623 | * SOCKS proxy type. |
8eebd221 |
624 | */ |
625 | |
6971bbe7 |
626 | /* SOCKS version 4 */ |
627 | int proxy_socks4_negotiate (Proxy_Socket p, int change) |
8eebd221 |
628 | { |
6971bbe7 |
629 | if (p->state == PROXY_CHANGE_NEW) { |
630 | |
631 | /* request format: |
632 | * version number (1 byte) = 4 |
633 | * command code (1 byte) |
634 | * 1 = CONNECT |
635 | * 2 = BIND |
636 | * dest. port (2 bytes) [network order] |
637 | * dest. address (4 bytes) |
638 | * user ID (variable length, null terminated string) |
639 | */ |
640 | |
641 | int length; |
642 | char * command; |
643 | |
644 | if (sk_addrtype(p->remote_addr) != AF_INET) { |
7983f47e |
645 | plug_closing(p->plug, "Proxy error: SOCKS version 4 does" |
646 | " not support IPv6", PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
647 | return 1; |
648 | } |
649 | |
650 | length = strlen(cfg.proxy_username) + 9; |
de9aaffb |
651 | command = (char*) smalloc(length); |
6971bbe7 |
652 | strcpy(command + 8, cfg.proxy_username); |
653 | |
654 | command[0] = 4; /* version 4 */ |
655 | command[1] = 1; /* CONNECT command */ |
656 | |
657 | /* port */ |
658 | command[2] = (char) (p->remote_port >> 8) & 0xff; |
659 | command[3] = (char) p->remote_port & 0xff; |
660 | |
661 | /* address */ |
662 | sk_addrcopy(p->remote_addr, command + 4); |
663 | |
664 | sk_write(p->sub_socket, command, length); |
de9aaffb |
665 | sfree(command); |
6971bbe7 |
666 | |
667 | p->state = 1; |
668 | return 0; |
669 | } |
670 | |
671 | if (change == PROXY_CHANGE_CLOSING) { |
672 | /* if our proxy negotiation process involves closing and opening |
673 | * new sockets, then we would want to intercept this closing |
674 | * callback when we were expecting it. if we aren't anticipating |
675 | * a socket close, then some error must have occurred. we'll |
676 | * just pass those errors up to the backend. |
677 | */ |
678 | return plug_closing(p->plug, p->closing_error_msg, |
679 | p->closing_error_code, |
680 | p->closing_calling_back); |
681 | } |
682 | |
683 | if (change == PROXY_CHANGE_SENT) { |
684 | /* some (or all) of what we wrote to the proxy was sent. |
685 | * we don't do anything new, however, until we receive the |
686 | * proxy's response. we might want to set a timer so we can |
687 | * timeout the proxy negotiation after a while... |
688 | */ |
689 | return 0; |
690 | } |
691 | |
692 | if (change == PROXY_CHANGE_ACCEPTING) { |
693 | /* we should _never_ see this, as we are using our socket to |
694 | * connect to a proxy, not accepting inbound connections. |
695 | * what should we do? close the socket with an appropriate |
696 | * error message? |
697 | */ |
698 | return plug_accepting(p->plug, p->accepting_sock); |
699 | } |
700 | |
701 | if (change == PROXY_CHANGE_RECEIVE) { |
702 | /* we have received data from the underlying socket, which |
703 | * we'll need to parse, process, and respond to appropriately. |
704 | */ |
705 | |
706 | if (p->state == 1) { |
707 | /* response format: |
708 | * version number (1 byte) = 4 |
709 | * reply code (1 byte) |
710 | * 90 = request granted |
711 | * 91 = request rejected or failed |
712 | * 92 = request rejected due to lack of IDENTD on client |
713 | * 93 = request rejected due to difference in user ID |
714 | * (what we sent vs. what IDENTD said) |
715 | * dest. port (2 bytes) |
716 | * dest. address (4 bytes) |
717 | */ |
718 | |
7983f47e |
719 | char data[8]; |
6971bbe7 |
720 | |
7983f47e |
721 | if (bufchain_size(&p->pending_input_data) < 8) |
722 | return 1; /* not got anything yet */ |
723 | |
6971bbe7 |
724 | /* get the response */ |
7983f47e |
725 | bufchain_fetch(&p->pending_input_data, data, 8); |
6971bbe7 |
726 | |
727 | if (data[0] != 0) { |
7983f47e |
728 | plug_closing(p->plug, "Proxy error: SOCKS proxy responded with " |
6971bbe7 |
729 | "unexpected reply code version", |
730 | PROXY_ERROR_GENERAL, 0); |
731 | return 1; |
732 | } |
733 | |
734 | if (data[1] != 90) { |
735 | |
736 | switch (data[1]) { |
737 | case 92: |
7983f47e |
738 | plug_closing(p->plug, "Proxy error: SOCKS server wanted IDENTD on client", |
6971bbe7 |
739 | PROXY_ERROR_GENERAL, 0); |
740 | break; |
741 | case 93: |
7983f47e |
742 | plug_closing(p->plug, "Proxy error: Username and IDENTD on client don't agree", |
6971bbe7 |
743 | PROXY_ERROR_GENERAL, 0); |
744 | break; |
745 | case 91: |
746 | default: |
7983f47e |
747 | plug_closing(p->plug, "Proxy error: Error while communicating with proxy", |
6971bbe7 |
748 | PROXY_ERROR_GENERAL, 0); |
749 | break; |
750 | } |
751 | |
752 | return 1; |
753 | } |
7983f47e |
754 | bufchain_consume(&p->pending_input_data, 8); |
6971bbe7 |
755 | |
756 | /* we're done */ |
757 | proxy_activate(p); |
758 | /* proxy activate will have dealt with |
759 | * whatever is left of the buffer */ |
760 | return 1; |
761 | } |
762 | } |
763 | |
7983f47e |
764 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
6971bbe7 |
765 | PROXY_ERROR_UNEXPECTED, 0); |
766 | return 1; |
767 | } |
768 | |
769 | /* SOCKS version 5 */ |
770 | int proxy_socks5_negotiate (Proxy_Socket p, int change) |
771 | { |
772 | if (p->state == PROXY_CHANGE_NEW) { |
773 | |
774 | /* initial command: |
775 | * version number (1 byte) = 5 |
776 | * number of available authentication methods (1 byte) |
777 | * available authentication methods (1 byte * previous value) |
778 | * authentication methods: |
779 | * 0x00 = no authentication |
780 | * 0x01 = GSSAPI |
781 | * 0x02 = username/password |
782 | * 0x03 = CHAP |
783 | */ |
784 | |
aab91a3e |
785 | char command[4]; |
786 | int len; |
6971bbe7 |
787 | |
788 | command[0] = 5; /* version 5 */ |
aab91a3e |
789 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
790 | command[1] = 2; /* two methods supported: */ |
791 | command[2] = 0x00; /* no authentication */ |
792 | command[3] = 0x02; /* username/password */ |
793 | len = 4; |
794 | } else { |
795 | command[1] = 1; /* one methods supported: */ |
796 | command[2] = 0x00; /* no authentication */ |
797 | len = 3; |
798 | } |
6971bbe7 |
799 | |
aab91a3e |
800 | sk_write(p->sub_socket, command, len); |
6971bbe7 |
801 | |
802 | p->state = 1; |
803 | return 0; |
804 | } |
805 | |
806 | if (change == PROXY_CHANGE_CLOSING) { |
807 | /* if our proxy negotiation process involves closing and opening |
808 | * new sockets, then we would want to intercept this closing |
809 | * callback when we were expecting it. if we aren't anticipating |
810 | * a socket close, then some error must have occurred. we'll |
811 | * just pass those errors up to the backend. |
812 | */ |
813 | return plug_closing(p->plug, p->closing_error_msg, |
814 | p->closing_error_code, |
815 | p->closing_calling_back); |
816 | } |
817 | |
818 | if (change == PROXY_CHANGE_SENT) { |
819 | /* some (or all) of what we wrote to the proxy was sent. |
820 | * we don't do anything new, however, until we receive the |
821 | * proxy's response. we might want to set a timer so we can |
822 | * timeout the proxy negotiation after a while... |
823 | */ |
824 | return 0; |
825 | } |
826 | |
827 | if (change == PROXY_CHANGE_ACCEPTING) { |
828 | /* we should _never_ see this, as we are using our socket to |
829 | * connect to a proxy, not accepting inbound connections. |
830 | * what should we do? close the socket with an appropriate |
831 | * error message? |
832 | */ |
833 | return plug_accepting(p->plug, p->accepting_sock); |
834 | } |
835 | |
836 | if (change == PROXY_CHANGE_RECEIVE) { |
837 | /* we have received data from the underlying socket, which |
838 | * we'll need to parse, process, and respond to appropriately. |
839 | */ |
840 | |
6971bbe7 |
841 | if (p->state == 1) { |
842 | |
843 | /* initial response: |
844 | * version number (1 byte) = 5 |
845 | * authentication method (1 byte) |
846 | * authentication methods: |
847 | * 0x00 = no authentication |
848 | * 0x01 = GSSAPI |
849 | * 0x02 = username/password |
850 | * 0x03 = CHAP |
851 | * 0xff = no acceptable methods |
852 | */ |
7983f47e |
853 | char data[2]; |
854 | |
855 | if (bufchain_size(&p->pending_input_data) < 2) |
856 | return 1; /* not got anything yet */ |
6971bbe7 |
857 | |
858 | /* get the response */ |
7983f47e |
859 | bufchain_fetch(&p->pending_input_data, data, 2); |
6971bbe7 |
860 | |
861 | if (data[0] != 5) { |
7983f47e |
862 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned unexpected version", |
6971bbe7 |
863 | PROXY_ERROR_GENERAL, 0); |
864 | return 1; |
865 | } |
866 | |
867 | if (data[1] == 0x00) p->state = 2; /* no authentication needed */ |
868 | else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */ |
869 | else if (data[1] == 0x02) p->state = 5; /* username/password authentication */ |
870 | else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */ |
871 | else { |
7983f47e |
872 | plug_closing(p->plug, "Proxy error: SOCKS proxy did not accept our authentication", |
6971bbe7 |
873 | PROXY_ERROR_GENERAL, 0); |
874 | return 1; |
875 | } |
aab91a3e |
876 | bufchain_consume(&p->pending_input_data, 2); |
877 | } |
878 | |
879 | if (p->state == 7) { |
880 | |
881 | /* password authentication reply format: |
882 | * version number (1 bytes) = 1 |
883 | * reply code (1 byte) |
884 | * 0 = succeeded |
885 | * >0 = failed |
886 | */ |
7983f47e |
887 | char data[2]; |
888 | |
889 | if (bufchain_size(&p->pending_input_data) < 2) |
890 | return 1; /* not got anything yet */ |
aab91a3e |
891 | |
892 | /* get the response */ |
7983f47e |
893 | bufchain_fetch(&p->pending_input_data, data, 2); |
aab91a3e |
894 | |
895 | if (data[0] != 1) { |
7983f47e |
896 | plug_closing(p->plug, "Proxy error: SOCKS password " |
897 | "subnegotiation contained wrong version number", |
aab91a3e |
898 | PROXY_ERROR_GENERAL, 0); |
899 | return 1; |
900 | } |
901 | |
902 | if (data[1] != 0) { |
903 | |
7983f47e |
904 | plug_closing(p->plug, "Proxy error: SOCKS proxy refused" |
905 | " password authentication", |
aab91a3e |
906 | PROXY_ERROR_GENERAL, 0); |
907 | return 1; |
908 | } |
909 | |
910 | bufchain_consume(&p->pending_input_data, 2); |
911 | p->state = 2; /* now proceed as authenticated */ |
6971bbe7 |
912 | } |
913 | |
914 | if (p->state == 2) { |
915 | |
916 | /* request format: |
917 | * version number (1 byte) = 5 |
918 | * command code (1 byte) |
919 | * 1 = CONNECT |
920 | * 2 = BIND |
921 | * 3 = UDP ASSOCIATE |
922 | * reserved (1 byte) = 0x00 |
923 | * address type (1 byte) |
924 | * 1 = IPv4 |
925 | * 3 = domainname (first byte has length, no terminating null) |
926 | * 4 = IPv6 |
927 | * dest. address (variable) |
928 | * dest. port (2 bytes) [network order] |
929 | */ |
930 | |
931 | char command[22]; |
932 | int len; |
933 | |
934 | if (sk_addrtype(p->remote_addr) == AF_INET) { |
935 | len = 10; |
936 | command[3] = 1; /* IPv4 */ |
937 | } else { |
938 | len = 22; |
939 | command[3] = 4; /* IPv6 */ |
940 | } |
941 | |
942 | command[0] = 5; /* version 5 */ |
943 | command[1] = 1; /* CONNECT command */ |
944 | command[2] = 0x00; |
945 | |
946 | /* address */ |
947 | sk_addrcopy(p->remote_addr, command+4); |
948 | |
949 | /* port */ |
950 | command[len-2] = (char) (p->remote_port >> 8) & 0xff; |
951 | command[len-1] = (char) p->remote_port & 0xff; |
952 | |
953 | sk_write(p->sub_socket, command, len); |
954 | |
955 | p->state = 3; |
956 | return 1; |
957 | } |
958 | |
959 | if (p->state == 3) { |
960 | |
961 | /* reply format: |
962 | * version number (1 bytes) = 5 |
963 | * reply code (1 byte) |
964 | * 0 = succeeded |
965 | * 1 = general SOCKS server failure |
966 | * 2 = connection not allowed by ruleset |
967 | * 3 = network unreachable |
968 | * 4 = host unreachable |
969 | * 5 = connection refused |
970 | * 6 = TTL expired |
971 | * 7 = command not supported |
972 | * 8 = address type not supported |
973 | * reserved (1 byte) = x00 |
974 | * address type (1 byte) |
975 | * 1 = IPv4 |
976 | * 3 = domainname (first byte has length, no terminating null) |
977 | * 4 = IPv6 |
978 | * server bound address (variable) |
979 | * server bound port (2 bytes) [network order] |
980 | */ |
7983f47e |
981 | char data[5]; |
982 | int len; |
983 | |
984 | /* First 5 bytes of packet are enough to tell its length. */ |
985 | if (bufchain_size(&p->pending_input_data) < 5) |
986 | return 1; /* not got anything yet */ |
6971bbe7 |
987 | |
988 | /* get the response */ |
7983f47e |
989 | bufchain_fetch(&p->pending_input_data, data, 5); |
6971bbe7 |
990 | |
991 | if (data[0] != 5) { |
7983f47e |
992 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned wrong version number", |
6971bbe7 |
993 | PROXY_ERROR_GENERAL, 0); |
994 | return 1; |
995 | } |
996 | |
997 | if (data[1] != 0) { |
7983f47e |
998 | char buf[256]; |
999 | |
1000 | strcpy(buf, "Proxy error: "); |
6971bbe7 |
1001 | |
1002 | switch (data[1]) { |
7983f47e |
1003 | case 1: strcat(buf, "General SOCKS server failure"); break; |
1004 | case 2: strcat(buf, "Connection not allowed by ruleset"); break; |
1005 | case 3: strcat(buf, "Network unreachable"); break; |
1006 | case 4: strcat(buf, "Host unreachable"); break; |
1007 | case 5: strcat(buf, "Connection refused"); break; |
1008 | case 6: strcat(buf, "TTL expired"); break; |
1009 | case 7: strcat(buf, "Command not supported"); break; |
1010 | case 8: strcat(buf, "Address type not supported"); break; |
1011 | default: sprintf(buf+strlen(buf), |
1012 | "Unrecognised SOCKS error code %d", |
1013 | data[1]); |
6971bbe7 |
1014 | break; |
1015 | } |
7983f47e |
1016 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
1017 | |
1018 | return 1; |
1019 | } |
6971bbe7 |
1020 | |
7983f47e |
1021 | /* |
1022 | * Eat the rest of the reply packet. |
1023 | */ |
1024 | len = 6; /* first 4 bytes, last 2 */ |
1025 | switch (data[3]) { |
1026 | case 1: len += 4; break; /* IPv4 address */ |
1027 | case 4: len += 16; break;/* IPv6 address */ |
1028 | case 3: len += (unsigned char)data[4]; break; /* domain name */ |
1029 | default: |
1030 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned " |
1031 | "unrecognised address format", |
1032 | PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
1033 | return 1; |
1034 | } |
7983f47e |
1035 | if (bufchain_size(&p->pending_input_data) < len) |
1036 | return 1; /* not got whole reply yet */ |
1037 | bufchain_consume(&p->pending_input_data, len); |
6971bbe7 |
1038 | |
1039 | /* we're done */ |
1040 | proxy_activate(p); |
6971bbe7 |
1041 | return 1; |
1042 | } |
1043 | |
1044 | if (p->state == 4) { |
1045 | /* TODO: Handle GSSAPI authentication */ |
2192a8e4 |
1046 | plug_closing(p->plug, "Proxy error: We don't support GSSAPI authentication", |
6971bbe7 |
1047 | PROXY_ERROR_GENERAL, 0); |
1048 | return 1; |
1049 | } |
1050 | |
1051 | if (p->state == 5) { |
aab91a3e |
1052 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
1053 | char userpwbuf[514]; |
1054 | int ulen, plen; |
1055 | ulen = strlen(cfg.proxy_username); |
1056 | if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1; |
1057 | plen = strlen(cfg.proxy_password); |
1058 | if (plen > 255) plen = 255; if (plen < 1) plen = 1; |
1059 | userpwbuf[0] = 1; /* version number of subnegotiation */ |
1060 | userpwbuf[1] = ulen; |
1061 | memcpy(userpwbuf+2, cfg.proxy_username, ulen); |
1062 | userpwbuf[ulen+2] = plen; |
1063 | memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen); |
1064 | sk_write(p->sub_socket, userpwbuf, ulen + plen + 3); |
1065 | p->state = 7; |
1066 | } else |
2192a8e4 |
1067 | plug_closing(p->plug, "Proxy error: Server chose " |
aab91a3e |
1068 | "username/password authentication but we " |
1069 | "didn't offer it!", |
6971bbe7 |
1070 | PROXY_ERROR_GENERAL, 0); |
1071 | return 1; |
1072 | } |
1073 | |
1074 | if (p->state == 6) { |
1075 | /* TODO: Handle CHAP authentication */ |
2192a8e4 |
1076 | plug_closing(p->plug, "Proxy error: We don't support CHAP authentication", |
6971bbe7 |
1077 | PROXY_ERROR_GENERAL, 0); |
1078 | return 1; |
1079 | } |
aab91a3e |
1080 | |
6971bbe7 |
1081 | } |
1082 | |
2192a8e4 |
1083 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
6971bbe7 |
1084 | PROXY_ERROR_UNEXPECTED, 0); |
1085 | return 1; |
8eebd221 |
1086 | } |
1087 | |
1088 | /* ---------------------------------------------------------------------- |
0e8f4cda |
1089 | * `Telnet' proxy type. |
8eebd221 |
1090 | * |
1091 | * (This is for ad-hoc proxies where you connect to the proxy's |
1092 | * telnet port and send a command such as `connect host port'. The |
1093 | * command is configurable, since this proxy type is typically not |
1094 | * standardised or at all well-defined.) |
1095 | */ |
1096 | |
1097 | int proxy_telnet_negotiate (Proxy_Socket p, int change) |
1098 | { |
0e8f4cda |
1099 | if (p->state == PROXY_CHANGE_NEW) { |
1100 | |
1101 | int so = 0, eo = 0; |
1102 | |
1103 | /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, |
2d129d8e |
1104 | * %%, %host, %port, %user, and %pass |
0e8f4cda |
1105 | */ |
1106 | |
1107 | while (cfg.proxy_telnet_command[eo] != 0) { |
1108 | |
1109 | /* scan forward until we hit end-of-line, |
1110 | * or an escape character (\ or %) */ |
1111 | while (cfg.proxy_telnet_command[eo] != 0 && |
1112 | cfg.proxy_telnet_command[eo] != '%' && |
1113 | cfg.proxy_telnet_command[eo] != '\\') eo++; |
1114 | |
1115 | /* if we hit eol, break out of our escaping loop */ |
1116 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1117 | |
1118 | /* if there was any unescaped text before the escape |
1119 | * character, send that now */ |
1120 | if (eo != so) { |
1121 | sk_write(p->sub_socket, |
1122 | cfg.proxy_telnet_command + so, eo - so); |
1123 | } |
1124 | |
1125 | so = eo++; |
1126 | |
1127 | /* if the escape character was the last character of |
1128 | * the line, we'll just stop and send it. */ |
1129 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1130 | |
1131 | if (cfg.proxy_telnet_command[so] == '\\') { |
1132 | |
1133 | /* we recognize \\, \%, \r, \n, \t, \x??. |
1134 | * anything else, we just send unescaped (including the \). |
1135 | */ |
1136 | |
1137 | switch (cfg.proxy_telnet_command[eo]) { |
1138 | |
1139 | case '\\': |
1140 | sk_write(p->sub_socket, "\\", 1); |
1141 | eo++; |
1142 | break; |
1143 | |
1144 | case '%': |
1145 | sk_write(p->sub_socket, "%%", 1); |
1146 | eo++; |
1147 | break; |
1148 | |
1149 | case 'r': |
1150 | sk_write(p->sub_socket, "\r", 1); |
1151 | eo++; |
1152 | break; |
1153 | |
1154 | case 'n': |
1155 | sk_write(p->sub_socket, "\n", 1); |
1156 | eo++; |
1157 | break; |
1158 | |
1159 | case 't': |
1160 | sk_write(p->sub_socket, "\t", 1); |
1161 | eo++; |
1162 | break; |
1163 | |
1164 | case 'x': |
1165 | case 'X': |
1166 | { |
1167 | /* escaped hexadecimal value (ie. \xff) */ |
1168 | unsigned char v = 0; |
1169 | int i = 0; |
1170 | |
1171 | for (;;) { |
1172 | eo++; |
1173 | if (cfg.proxy_telnet_command[eo] >= '0' && |
1174 | cfg.proxy_telnet_command[eo] <= '9') |
1175 | v += cfg.proxy_telnet_command[eo] - '0'; |
1176 | else if (cfg.proxy_telnet_command[eo] >= 'a' && |
1177 | cfg.proxy_telnet_command[eo] <= 'f') |
1178 | v += cfg.proxy_telnet_command[eo] - 'a' + 10; |
1179 | else if (cfg.proxy_telnet_command[eo] >= 'A' && |
1180 | cfg.proxy_telnet_command[eo] <= 'F') |
1181 | v += cfg.proxy_telnet_command[eo] - 'A' + 10; |
1182 | else { |
1183 | /* non hex character, so we abort and just |
1184 | * send the whole thing unescaped (including \x) |
1185 | */ |
1186 | sk_write(p->sub_socket, "\\", 1); |
1187 | eo = so + 1; |
1188 | break; |
1189 | } |
1190 | |
1191 | /* we only extract two hex characters */ |
1192 | if (i == 1) { |
1193 | sk_write(p->sub_socket, &v, 1); |
1194 | eo++; |
1195 | break; |
1196 | } |
1197 | |
1198 | i++; |
1199 | v <<= 4; |
1200 | } |
1201 | } |
1202 | break; |
1203 | |
1204 | default: |
1205 | sk_write(p->sub_socket, |
1206 | cfg.proxy_telnet_command + so, 2); |
1207 | eo++; |
1208 | break; |
1209 | } |
1210 | } else { |
1211 | |
2d129d8e |
1212 | /* % escape. we recognize %%, %host, %port, %user, %pass. |
1213 | * anything else, we just send unescaped (including the %). |
1214 | */ |
0e8f4cda |
1215 | |
1216 | if (cfg.proxy_telnet_command[eo] == '%') { |
1217 | sk_write(p->sub_socket, "%", 1); |
1218 | eo++; |
2d129d8e |
1219 | } |
0e8f4cda |
1220 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1221 | "host", 4) == 0) { |
1222 | char dest[64]; |
1223 | sk_getaddr(p->remote_addr, dest, 64); |
1224 | sk_write(p->sub_socket, dest, strlen(dest)); |
1225 | eo += 4; |
2d129d8e |
1226 | } |
0e8f4cda |
1227 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1228 | "port", 4) == 0) { |
1229 | char port[8]; |
1230 | sprintf(port, "%i", p->remote_port); |
1231 | sk_write(p->sub_socket, port, strlen(port)); |
1232 | eo += 4; |
2d129d8e |
1233 | } |
1234 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1235 | "user", 4) == 0) { |
1236 | sk_write(p->sub_socket, cfg.proxy_username, |
1237 | strlen(cfg.proxy_username)); |
1238 | eo += 4; |
1239 | } |
1240 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1241 | "pass", 4) == 0) { |
1242 | sk_write(p->sub_socket, cfg.proxy_password, |
1243 | strlen(cfg.proxy_password)); |
1244 | eo += 4; |
1245 | } |
0e8f4cda |
1246 | else { |
1247 | /* we don't escape this, so send the % now, and |
1248 | * don't advance eo, so that we'll consider the |
1249 | * text immediately following the % as unescaped. |
1250 | */ |
1251 | sk_write(p->sub_socket, "%", 1); |
1252 | } |
1253 | } |
1254 | |
1255 | /* resume scanning for additional escapes after this one. */ |
1256 | so = eo; |
1257 | } |
1258 | |
1259 | /* if there is any unescaped text at the end of the line, send it */ |
1260 | if (eo != so) { |
1261 | sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); |
1262 | } |
1263 | |
1264 | p->state = 1; |
0e8f4cda |
1265 | return 0; |
1266 | } |
1267 | |
1268 | if (change == PROXY_CHANGE_CLOSING) { |
1269 | /* if our proxy negotiation process involves closing and opening |
1270 | * new sockets, then we would want to intercept this closing |
1271 | * callback when we were expecting it. if we aren't anticipating |
1272 | * a socket close, then some error must have occurred. we'll |
1273 | * just pass those errors up to the backend. |
1274 | */ |
1275 | return plug_closing(p->plug, p->closing_error_msg, |
1276 | p->closing_error_code, |
1277 | p->closing_calling_back); |
1278 | } |
1279 | |
1280 | if (change == PROXY_CHANGE_SENT) { |
1281 | /* some (or all) of what we wrote to the proxy was sent. |
1282 | * we don't do anything new, however, until we receive the |
1283 | * proxy's response. we might want to set a timer so we can |
1284 | * timeout the proxy negotiation after a while... |
1285 | */ |
1286 | return 0; |
1287 | } |
1288 | |
1289 | if (change == PROXY_CHANGE_ACCEPTING) { |
1290 | /* we should _never_ see this, as we are using our socket to |
1291 | * connect to a proxy, not accepting inbound connections. |
1292 | * what should we do? close the socket with an appropriate |
1293 | * error message? |
1294 | */ |
1295 | return plug_accepting(p->plug, p->accepting_sock); |
1296 | } |
1297 | |
1298 | if (change == PROXY_CHANGE_RECEIVE) { |
1299 | /* we have received data from the underlying socket, which |
1300 | * we'll need to parse, process, and respond to appropriately. |
1301 | */ |
1302 | |
1303 | /* we're done */ |
1304 | proxy_activate(p); |
1305 | /* proxy activate will have dealt with |
1306 | * whatever is left of the buffer */ |
1307 | return 1; |
1308 | } |
1309 | |
2192a8e4 |
1310 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
0e8f4cda |
1311 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
1312 | return 1; |
8eebd221 |
1313 | } |