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 | |
7983f47e |
8 | #include <assert.h> |
de9aaffb |
9 | #include <ctype.h> |
10 | #include <string.h> |
7983f47e |
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; |
2d129d8e |
25 | long output_before, output_after; |
26 | |
8eebd221 |
27 | p->state = PROXY_STATE_ACTIVE; |
28 | |
2d129d8e |
29 | /* we want to ignore new receive events until we have sent |
30 | * all of our buffered receive data. |
31 | */ |
8eebd221 |
32 | sk_set_frozen(p->sub_socket, 1); |
33 | |
2d129d8e |
34 | /* how many bytes of output have we buffered? */ |
35 | output_before = bufchain_size(&p->pending_oob_output_data) + |
36 | bufchain_size(&p->pending_output_data); |
37 | /* and keep track of how many bytes do not get sent. */ |
38 | output_after = 0; |
39 | |
0e8f4cda |
40 | /* send buffered OOB writes */ |
8eebd221 |
41 | while (bufchain_size(&p->pending_oob_output_data) > 0) { |
42 | bufchain_prefix(&p->pending_oob_output_data, &data, &len); |
2d129d8e |
43 | output_after += sk_write_oob(p->sub_socket, data, len); |
8eebd221 |
44 | bufchain_consume(&p->pending_oob_output_data, len); |
45 | } |
8eebd221 |
46 | |
0e8f4cda |
47 | /* send buffered normal writes */ |
8eebd221 |
48 | while (bufchain_size(&p->pending_output_data) > 0) { |
49 | bufchain_prefix(&p->pending_output_data, &data, &len); |
2d129d8e |
50 | output_after += sk_write(p->sub_socket, data, len); |
8eebd221 |
51 | bufchain_consume(&p->pending_output_data, len); |
52 | } |
2d129d8e |
53 | |
54 | /* if we managed to send any data, let the higher levels know. */ |
55 | if (output_after < output_before) |
56 | plug_sent(p->plug, output_after); |
8eebd221 |
57 | |
0e8f4cda |
58 | /* if we were asked to flush the output during |
59 | * the proxy negotiation process, do so now. |
60 | */ |
8eebd221 |
61 | if (p->pending_flush) sk_flush(p->sub_socket); |
8eebd221 |
62 | |
2d129d8e |
63 | /* if the backend wanted the socket unfrozen, try to unfreeze. |
64 | * our set_frozen handler will flush buffered receive data before |
65 | * unfreezing the actual underlying socket. |
66 | */ |
67 | if (!p->freeze) |
68 | sk_set_frozen((Socket)p, 0); |
8eebd221 |
69 | } |
70 | |
71 | /* basic proxy socket functions */ |
72 | |
73 | static Plug sk_proxy_plug (Socket s, Plug p) |
74 | { |
75 | Proxy_Socket ps = (Proxy_Socket) s; |
76 | Plug ret = ps->plug; |
77 | if (p) |
78 | ps->plug = p; |
79 | return ret; |
80 | } |
81 | |
82 | static void sk_proxy_close (Socket s) |
83 | { |
84 | Proxy_Socket ps = (Proxy_Socket) s; |
85 | |
8eebd221 |
86 | sk_close(ps->sub_socket); |
87 | sfree(ps); |
88 | } |
89 | |
90 | static int sk_proxy_write (Socket s, char *data, int len) |
91 | { |
92 | Proxy_Socket ps = (Proxy_Socket) s; |
93 | |
8eebd221 |
94 | if (ps->state != PROXY_STATE_ACTIVE) { |
95 | bufchain_add(&ps->pending_output_data, data, len); |
96 | return bufchain_size(&ps->pending_output_data); |
97 | } |
98 | return sk_write(ps->sub_socket, data, len); |
99 | } |
100 | |
101 | static int sk_proxy_write_oob (Socket s, char *data, int len) |
102 | { |
103 | Proxy_Socket ps = (Proxy_Socket) s; |
104 | |
8eebd221 |
105 | if (ps->state != PROXY_STATE_ACTIVE) { |
106 | bufchain_clear(&ps->pending_output_data); |
107 | bufchain_clear(&ps->pending_oob_output_data); |
108 | bufchain_add(&ps->pending_oob_output_data, data, len); |
109 | return len; |
110 | } |
111 | return sk_write_oob(ps->sub_socket, data, len); |
112 | } |
113 | |
114 | static void sk_proxy_flush (Socket s) |
115 | { |
116 | Proxy_Socket ps = (Proxy_Socket) s; |
117 | |
8eebd221 |
118 | if (ps->state != PROXY_STATE_ACTIVE) { |
119 | ps->pending_flush = 1; |
120 | return; |
121 | } |
122 | sk_flush(ps->sub_socket); |
123 | } |
124 | |
125 | static void sk_proxy_set_private_ptr (Socket s, void *ptr) |
126 | { |
127 | Proxy_Socket ps = (Proxy_Socket) s; |
128 | sk_set_private_ptr(ps->sub_socket, ptr); |
129 | } |
130 | |
131 | static void * sk_proxy_get_private_ptr (Socket s) |
132 | { |
133 | Proxy_Socket ps = (Proxy_Socket) s; |
134 | return sk_get_private_ptr(ps->sub_socket); |
135 | } |
136 | |
137 | static void sk_proxy_set_frozen (Socket s, int is_frozen) |
138 | { |
139 | Proxy_Socket ps = (Proxy_Socket) s; |
140 | |
8eebd221 |
141 | if (ps->state != PROXY_STATE_ACTIVE) { |
142 | ps->freeze = is_frozen; |
143 | return; |
144 | } |
2d129d8e |
145 | |
146 | /* handle any remaining buffered recv data first */ |
147 | if (bufchain_size(&ps->pending_input_data) > 0) { |
148 | ps->freeze = is_frozen; |
149 | |
150 | /* loop while we still have buffered data, and while we are |
151 | * unfrozen. the plug_receive call in the loop could result |
152 | * in a call back into this function refreezing the socket, |
153 | * so we have to check each time. |
154 | */ |
155 | while (!ps->freeze && bufchain_size(&ps->pending_input_data) > 0) { |
68a49acb |
156 | void *data; |
2d129d8e |
157 | int len; |
158 | bufchain_prefix(&ps->pending_input_data, &data, &len); |
159 | plug_receive(ps->plug, 0, data, len); |
160 | bufchain_consume(&ps->pending_input_data, len); |
161 | } |
162 | |
163 | /* if we're still frozen, we'll have to wait for another |
164 | * call from the backend to finish unbuffering the data. |
165 | */ |
166 | if (ps->freeze) return; |
167 | } |
168 | |
8eebd221 |
169 | sk_set_frozen(ps->sub_socket, is_frozen); |
170 | } |
171 | |
172 | static char * sk_proxy_socket_error (Socket s) |
173 | { |
174 | Proxy_Socket ps = (Proxy_Socket) s; |
175 | if (ps->error != NULL || ps->sub_socket == NULL) { |
176 | return ps->error; |
177 | } |
178 | return sk_socket_error(ps->sub_socket); |
179 | } |
180 | |
181 | /* basic proxy plug functions */ |
182 | |
183 | static int plug_proxy_closing (Plug p, char *error_msg, |
184 | int error_code, int calling_back) |
185 | { |
186 | Proxy_Plug pp = (Proxy_Plug) p; |
187 | Proxy_Socket ps = pp->proxy_socket; |
188 | |
8eebd221 |
189 | if (ps->state != PROXY_STATE_ACTIVE) { |
190 | ps->closing_error_msg = error_msg; |
191 | ps->closing_error_code = error_code; |
192 | ps->closing_calling_back = calling_back; |
193 | return ps->negotiate(ps, PROXY_CHANGE_CLOSING); |
194 | } |
195 | return plug_closing(ps->plug, error_msg, |
196 | error_code, calling_back); |
197 | } |
198 | |
199 | static int plug_proxy_receive (Plug p, int urgent, char *data, int len) |
200 | { |
201 | Proxy_Plug pp = (Proxy_Plug) p; |
202 | Proxy_Socket ps = pp->proxy_socket; |
203 | |
8eebd221 |
204 | if (ps->state != PROXY_STATE_ACTIVE) { |
205 | /* we will lose the urgentness of this data, but since most, |
206 | * if not all, of this data will be consumed by the negotiation |
207 | * process, hopefully it won't affect the protocol above us |
208 | */ |
209 | bufchain_add(&ps->pending_input_data, data, len); |
210 | ps->receive_urgent = urgent; |
211 | ps->receive_data = data; |
212 | ps->receive_len = len; |
213 | return ps->negotiate(ps, PROXY_CHANGE_RECEIVE); |
214 | } |
215 | return plug_receive(ps->plug, urgent, data, len); |
216 | } |
217 | |
218 | static void plug_proxy_sent (Plug p, int bufsize) |
219 | { |
220 | Proxy_Plug pp = (Proxy_Plug) p; |
221 | Proxy_Socket ps = pp->proxy_socket; |
222 | |
8eebd221 |
223 | if (ps->state != PROXY_STATE_ACTIVE) { |
224 | ps->sent_bufsize = bufsize; |
225 | ps->negotiate(ps, PROXY_CHANGE_SENT); |
226 | return; |
227 | } |
228 | plug_sent(ps->plug, bufsize); |
229 | } |
230 | |
231 | static int plug_proxy_accepting (Plug p, void *sock) |
232 | { |
233 | Proxy_Plug pp = (Proxy_Plug) p; |
234 | Proxy_Socket ps = pp->proxy_socket; |
235 | |
8eebd221 |
236 | if (ps->state != PROXY_STATE_ACTIVE) { |
237 | ps->accepting_sock = sock; |
238 | return ps->negotiate(ps, PROXY_CHANGE_ACCEPTING); |
239 | } |
240 | return plug_accepting(ps->plug, sock); |
241 | } |
242 | |
243 | static int proxy_for_destination (SockAddr addr, char * hostname, int port) |
244 | { |
245 | int s = 0, e = 0; |
246 | char hostip[64]; |
247 | int hostip_len, hostname_len; |
248 | char * exclude_list; |
249 | |
250 | /* we want a string representation of the IP address for comparisons */ |
251 | sk_getaddr(addr, hostip, 64); |
252 | |
253 | hostip_len = strlen(hostip); |
254 | hostname_len = strlen(hostname); |
255 | |
256 | exclude_list = cfg.proxy_exclude_list; |
257 | |
258 | /* now parse the exclude list, and see if either our IP |
259 | * or hostname matches anything in it. |
260 | */ |
261 | |
262 | while (exclude_list[s]) { |
263 | while (exclude_list[s] && |
264 | (isspace(exclude_list[s]) || |
265 | exclude_list[s] == ',')) s++; |
266 | |
267 | if (!exclude_list[s]) break; |
268 | |
269 | e = s; |
270 | |
271 | while (exclude_list[e] && |
272 | (isalnum(exclude_list[e]) || |
273 | exclude_list[e] == '-' || |
274 | exclude_list[e] == '.' || |
275 | exclude_list[e] == '*')) e++; |
276 | |
277 | if (exclude_list[s] == '*') { |
278 | /* wildcard at beginning of entry */ |
279 | |
280 | if (strnicmp(hostip + hostip_len - (e - s - 1), |
281 | exclude_list + s + 1, e - s - 1) == 0 || |
282 | strnicmp(hostname + hostname_len - (e - s - 1), |
283 | exclude_list + s + 1, e - s - 1) == 0) |
284 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
285 | |
286 | } else if (exclude_list[e-1] == '*') { |
287 | /* wildcard at end of entry */ |
288 | |
289 | if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 || |
290 | strnicmp(hostname, exclude_list + s, e - s - 1) == 0) |
291 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
292 | |
293 | } else { |
294 | /* no wildcard at either end, so let's try an absolute |
295 | * match (ie. a specific IP) |
296 | */ |
297 | |
298 | if (stricmp(hostip, exclude_list + s) == 0) |
299 | return 0; /* IP/hostname excluded. do not use proxy. */ |
300 | if (stricmp(hostname, exclude_list + s) == 0) |
301 | return 0; /* IP/hostname excluded. do not use proxy. */ |
302 | } |
303 | |
304 | s = e; |
305 | } |
306 | |
307 | /* no matches in the exclude list, so use the proxy */ |
308 | return 1; |
309 | } |
310 | |
311 | Socket new_connection(SockAddr addr, char *hostname, |
312 | int port, int privport, |
313 | int oobinline, int nodelay, Plug plug) |
314 | { |
7b6c9b99 |
315 | static const struct socket_function_table socket_fn_table = { |
8eebd221 |
316 | sk_proxy_plug, |
317 | sk_proxy_close, |
318 | sk_proxy_write, |
319 | sk_proxy_write_oob, |
320 | sk_proxy_flush, |
321 | sk_proxy_set_private_ptr, |
322 | sk_proxy_get_private_ptr, |
323 | sk_proxy_set_frozen, |
324 | sk_proxy_socket_error |
325 | }; |
326 | |
7b6c9b99 |
327 | static const struct plug_function_table plug_fn_table = { |
8eebd221 |
328 | plug_proxy_closing, |
329 | plug_proxy_receive, |
330 | plug_proxy_sent, |
331 | plug_proxy_accepting |
332 | }; |
333 | |
334 | if (cfg.proxy_type != PROXY_NONE && |
335 | proxy_for_destination(addr, hostname, port)) |
336 | { |
337 | Proxy_Socket ret; |
338 | Proxy_Plug pplug; |
339 | SockAddr proxy_addr; |
340 | char * proxy_canonical_name; |
341 | |
342 | ret = smalloc(sizeof(struct Socket_proxy_tag)); |
343 | ret->fn = &socket_fn_table; |
344 | ret->plug = plug; |
345 | ret->remote_addr = addr; |
346 | ret->remote_port = port; |
347 | |
65c78e88 |
348 | ret->error = NULL; |
349 | ret->pending_flush = 0; |
350 | ret->freeze = 0; |
351 | |
8eebd221 |
352 | bufchain_init(&ret->pending_input_data); |
353 | bufchain_init(&ret->pending_output_data); |
354 | bufchain_init(&ret->pending_oob_output_data); |
355 | |
8eebd221 |
356 | ret->sub_socket = NULL; |
357 | ret->state = PROXY_STATE_NEW; |
2d129d8e |
358 | ret->negotiate = NULL; |
359 | |
8eebd221 |
360 | if (cfg.proxy_type == PROXY_HTTP) { |
361 | ret->negotiate = proxy_http_negotiate; |
362 | } else if (cfg.proxy_type == PROXY_SOCKS) { |
6971bbe7 |
363 | if (cfg.proxy_socks_version == 4) |
364 | ret->negotiate = proxy_socks4_negotiate; |
365 | else |
366 | ret->negotiate = proxy_socks5_negotiate; |
8eebd221 |
367 | } else if (cfg.proxy_type == PROXY_TELNET) { |
368 | ret->negotiate = proxy_telnet_negotiate; |
369 | } else { |
7983f47e |
370 | ret->error = "Proxy error: Unknown proxy method"; |
8eebd221 |
371 | return (Socket) ret; |
372 | } |
373 | |
374 | /* create the proxy plug to map calls from the actual |
375 | * socket into our proxy socket layer */ |
376 | pplug = smalloc(sizeof(struct Plug_proxy_tag)); |
377 | pplug->fn = &plug_fn_table; |
378 | pplug->proxy_socket = ret; |
379 | |
380 | /* look-up proxy */ |
381 | proxy_addr = sk_namelookup(cfg.proxy_host, |
382 | &proxy_canonical_name); |
383 | sfree(proxy_canonical_name); |
384 | |
385 | /* create the actual socket we will be using, |
386 | * connected to our proxy server and port. |
387 | */ |
388 | ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port, |
389 | privport, oobinline, |
390 | nodelay, (Plug) pplug); |
391 | if (sk_socket_error(ret->sub_socket) != NULL) |
392 | return (Socket) ret; |
393 | |
394 | sk_addr_free(proxy_addr); |
395 | |
396 | /* start the proxy negotiation process... */ |
397 | sk_set_frozen(ret->sub_socket, 0); |
398 | ret->negotiate(ret, PROXY_CHANGE_NEW); |
399 | |
400 | return (Socket) ret; |
401 | } |
402 | |
403 | /* no proxy, so just return the direct socket */ |
404 | return sk_new(addr, port, privport, oobinline, nodelay, plug); |
405 | } |
406 | |
407 | Socket new_listener(int port, Plug plug, int local_host_only) |
408 | { |
409 | /* TODO: SOCKS (and potentially others) support inbound |
410 | * TODO: connections via the proxy. support them. |
411 | */ |
412 | |
413 | return sk_newlistener(port, plug, local_host_only); |
414 | } |
415 | |
416 | /* ---------------------------------------------------------------------- |
417 | * HTTP CONNECT proxy type. |
418 | */ |
419 | |
420 | static int get_line_end (char * data, int len) |
421 | { |
422 | int off = 0; |
423 | |
424 | while (off < len) |
425 | { |
426 | if (data[off] == '\n') { |
427 | /* we have a newline */ |
428 | off++; |
429 | |
430 | /* is that the only thing on this line? */ |
431 | if (off <= 2) return off; |
432 | |
433 | /* if not, then there is the possibility that this header |
434 | * continues onto the next line, if it starts with a space |
435 | * or a tab. |
436 | */ |
437 | |
438 | if (off + 1 < len && |
439 | data[off+1] != ' ' && |
440 | data[off+1] != '\t') return off; |
441 | |
442 | /* the line does continue, so we have to keep going |
443 | * until we see an the header's "real" end of line. |
444 | */ |
445 | off++; |
446 | } |
447 | |
448 | off++; |
449 | } |
450 | |
451 | return -1; |
452 | } |
453 | |
454 | int proxy_http_negotiate (Proxy_Socket p, int change) |
455 | { |
456 | if (p->state == PROXY_STATE_NEW) { |
457 | /* we are just beginning the proxy negotiate process, |
458 | * so we'll send off the initial bits of the request. |
459 | * for this proxy method, it's just a simple HTTP |
460 | * request |
461 | */ |
0e8f4cda |
462 | char buf[256], dest[64]; |
8eebd221 |
463 | |
0e8f4cda |
464 | sk_getaddr(p->remote_addr, dest, 64); |
8eebd221 |
465 | |
1549e076 |
466 | sprintf(buf, "CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n", |
8eebd221 |
467 | dest, p->remote_port, dest, p->remote_port); |
468 | sk_write(p->sub_socket, buf, strlen(buf)); |
469 | |
1549e076 |
470 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
471 | char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)]; |
472 | char buf2[sizeof(buf)*4/3 + 100]; |
473 | int i, j, len; |
474 | sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password); |
475 | len = strlen(buf); |
476 | sprintf(buf2, "Proxy-Authorization: basic "); |
477 | for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4) |
478 | base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j); |
479 | strcpy(buf2+j, "\r\n"); |
480 | sk_write(p->sub_socket, buf2, strlen(buf2)); |
481 | } |
482 | |
483 | sprintf(buf, "\r\n"); |
484 | sk_write(p->sub_socket, buf, strlen(buf)); |
485 | |
8eebd221 |
486 | p->state = 1; |
8eebd221 |
487 | return 0; |
488 | } |
489 | |
490 | if (change == PROXY_CHANGE_CLOSING) { |
491 | /* if our proxy negotiation process involves closing and opening |
492 | * new sockets, then we would want to intercept this closing |
493 | * callback when we were expecting it. if we aren't anticipating |
494 | * a socket close, then some error must have occurred. we'll |
495 | * just pass those errors up to the backend. |
496 | */ |
497 | return plug_closing(p->plug, p->closing_error_msg, |
498 | p->closing_error_code, |
499 | p->closing_calling_back); |
500 | } |
501 | |
502 | if (change == PROXY_CHANGE_SENT) { |
503 | /* some (or all) of what we wrote to the proxy was sent. |
504 | * we don't do anything new, however, until we receive the |
505 | * proxy's response. we might want to set a timer so we can |
506 | * timeout the proxy negotiation after a while... |
507 | */ |
508 | return 0; |
509 | } |
510 | |
511 | if (change == PROXY_CHANGE_ACCEPTING) { |
512 | /* we should _never_ see this, as we are using our socket to |
513 | * connect to a proxy, not accepting inbound connections. |
514 | * what should we do? close the socket with an appropriate |
515 | * error message? |
516 | */ |
517 | return plug_accepting(p->plug, p->accepting_sock); |
518 | } |
519 | |
520 | if (change == PROXY_CHANGE_RECEIVE) { |
521 | /* we have received data from the underlying socket, which |
522 | * we'll need to parse, process, and respond to appropriately. |
523 | */ |
524 | |
7983f47e |
525 | char *data, *datap; |
8eebd221 |
526 | int len; |
527 | int eol; |
528 | |
529 | if (p->state == 1) { |
530 | |
531 | int min_ver, maj_ver, status; |
532 | |
533 | /* get the status line */ |
7983f47e |
534 | len = bufchain_size(&p->pending_input_data); |
535 | assert(len > 0); /* or we wouldn't be here */ |
536 | data = smalloc(len); |
537 | bufchain_fetch(&p->pending_input_data, data, len); |
538 | |
8eebd221 |
539 | eol = get_line_end(data, len); |
7983f47e |
540 | if (eol < 0) { |
541 | sfree(data); |
542 | return 1; |
543 | } |
8eebd221 |
544 | |
7983f47e |
545 | status = -1; |
546 | /* We can't rely on whether the %n incremented the sscanf return */ |
547 | if (sscanf((char *)data, "HTTP/%i.%i %n", |
548 | &maj_ver, &min_ver, &status) < 2 || status == -1) { |
549 | plug_closing(p->plug, "Proxy error: HTTP response was absent", |
550 | PROXY_ERROR_GENERAL, 0); |
551 | sfree(data); |
552 | return 1; |
553 | } |
8eebd221 |
554 | |
555 | /* remove the status line from the input buffer. */ |
556 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
557 | if (data[status] != '2') { |
8eebd221 |
558 | /* error */ |
7983f47e |
559 | char buf[1024]; |
560 | data[eol] = '\0'; |
561 | while (eol > status && |
562 | (data[eol-1] == '\r' || data[eol-1] == '\n')) |
563 | data[--eol] = '\0'; |
564 | sprintf(buf, "Proxy error: %.900s", |
565 | data+status); |
566 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
567 | sfree(data); |
8eebd221 |
568 | return 1; |
569 | } |
570 | |
7983f47e |
571 | sfree(data); |
572 | |
8eebd221 |
573 | p->state = 2; |
574 | } |
575 | |
576 | if (p->state == 2) { |
577 | |
578 | /* get headers. we're done when we get a |
579 | * header of length 2, (ie. just "\r\n") |
580 | */ |
581 | |
7983f47e |
582 | len = bufchain_size(&p->pending_input_data); |
583 | assert(len > 0); /* or we wouldn't be here */ |
584 | data = smalloc(len); |
585 | datap = data; |
586 | bufchain_fetch(&p->pending_input_data, data, len); |
587 | |
588 | eol = get_line_end(datap, len); |
589 | if (eol < 0) { |
590 | sfree(data); |
591 | return 1; |
592 | } |
8eebd221 |
593 | while (eol > 2) |
594 | { |
8eebd221 |
595 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
596 | datap += eol; |
597 | eol = get_line_end(datap, len); |
8eebd221 |
598 | } |
599 | |
600 | if (eol == 2) { |
601 | /* we're done */ |
602 | bufchain_consume(&p->pending_input_data, 2); |
603 | proxy_activate(p); |
604 | /* proxy activate will have dealt with |
605 | * whatever is left of the buffer */ |
7983f47e |
606 | sfree(data); |
8eebd221 |
607 | return 1; |
608 | } |
609 | |
7983f47e |
610 | sfree(data); |
8eebd221 |
611 | return 1; |
612 | } |
613 | } |
614 | |
7983f47e |
615 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
8eebd221 |
616 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
617 | return 1; |
8eebd221 |
618 | } |
619 | |
620 | /* ---------------------------------------------------------------------- |
6971bbe7 |
621 | * SOCKS proxy type. |
8eebd221 |
622 | */ |
623 | |
6971bbe7 |
624 | /* SOCKS version 4 */ |
625 | int proxy_socks4_negotiate (Proxy_Socket p, int change) |
8eebd221 |
626 | { |
6971bbe7 |
627 | if (p->state == PROXY_CHANGE_NEW) { |
628 | |
629 | /* request format: |
630 | * version number (1 byte) = 4 |
631 | * command code (1 byte) |
632 | * 1 = CONNECT |
633 | * 2 = BIND |
634 | * dest. port (2 bytes) [network order] |
635 | * dest. address (4 bytes) |
636 | * user ID (variable length, null terminated string) |
637 | */ |
638 | |
639 | int length; |
640 | char * command; |
641 | |
68a49acb |
642 | if (sk_addrtype(p->remote_addr) != ADDRTYPE_IPV4) { |
7983f47e |
643 | plug_closing(p->plug, "Proxy error: SOCKS version 4 does" |
644 | " not support IPv6", PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
645 | return 1; |
646 | } |
647 | |
648 | length = strlen(cfg.proxy_username) + 9; |
de9aaffb |
649 | command = (char*) smalloc(length); |
6971bbe7 |
650 | strcpy(command + 8, cfg.proxy_username); |
651 | |
652 | command[0] = 4; /* version 4 */ |
653 | command[1] = 1; /* CONNECT command */ |
654 | |
655 | /* port */ |
656 | command[2] = (char) (p->remote_port >> 8) & 0xff; |
657 | command[3] = (char) p->remote_port & 0xff; |
658 | |
659 | /* address */ |
660 | sk_addrcopy(p->remote_addr, command + 4); |
661 | |
662 | sk_write(p->sub_socket, command, length); |
de9aaffb |
663 | sfree(command); |
6971bbe7 |
664 | |
665 | p->state = 1; |
666 | return 0; |
667 | } |
668 | |
669 | if (change == PROXY_CHANGE_CLOSING) { |
670 | /* if our proxy negotiation process involves closing and opening |
671 | * new sockets, then we would want to intercept this closing |
672 | * callback when we were expecting it. if we aren't anticipating |
673 | * a socket close, then some error must have occurred. we'll |
674 | * just pass those errors up to the backend. |
675 | */ |
676 | return plug_closing(p->plug, p->closing_error_msg, |
677 | p->closing_error_code, |
678 | p->closing_calling_back); |
679 | } |
680 | |
681 | if (change == PROXY_CHANGE_SENT) { |
682 | /* some (or all) of what we wrote to the proxy was sent. |
683 | * we don't do anything new, however, until we receive the |
684 | * proxy's response. we might want to set a timer so we can |
685 | * timeout the proxy negotiation after a while... |
686 | */ |
687 | return 0; |
688 | } |
689 | |
690 | if (change == PROXY_CHANGE_ACCEPTING) { |
691 | /* we should _never_ see this, as we are using our socket to |
692 | * connect to a proxy, not accepting inbound connections. |
693 | * what should we do? close the socket with an appropriate |
694 | * error message? |
695 | */ |
696 | return plug_accepting(p->plug, p->accepting_sock); |
697 | } |
698 | |
699 | if (change == PROXY_CHANGE_RECEIVE) { |
700 | /* we have received data from the underlying socket, which |
701 | * we'll need to parse, process, and respond to appropriately. |
702 | */ |
703 | |
704 | if (p->state == 1) { |
705 | /* response format: |
706 | * version number (1 byte) = 4 |
707 | * reply code (1 byte) |
708 | * 90 = request granted |
709 | * 91 = request rejected or failed |
710 | * 92 = request rejected due to lack of IDENTD on client |
711 | * 93 = request rejected due to difference in user ID |
712 | * (what we sent vs. what IDENTD said) |
713 | * dest. port (2 bytes) |
714 | * dest. address (4 bytes) |
715 | */ |
716 | |
7983f47e |
717 | char data[8]; |
6971bbe7 |
718 | |
7983f47e |
719 | if (bufchain_size(&p->pending_input_data) < 8) |
720 | return 1; /* not got anything yet */ |
721 | |
6971bbe7 |
722 | /* get the response */ |
7983f47e |
723 | bufchain_fetch(&p->pending_input_data, data, 8); |
6971bbe7 |
724 | |
725 | if (data[0] != 0) { |
7983f47e |
726 | plug_closing(p->plug, "Proxy error: SOCKS proxy responded with " |
6971bbe7 |
727 | "unexpected reply code version", |
728 | PROXY_ERROR_GENERAL, 0); |
729 | return 1; |
730 | } |
731 | |
732 | if (data[1] != 90) { |
733 | |
734 | switch (data[1]) { |
735 | case 92: |
7983f47e |
736 | plug_closing(p->plug, "Proxy error: SOCKS server wanted IDENTD on client", |
6971bbe7 |
737 | PROXY_ERROR_GENERAL, 0); |
738 | break; |
739 | case 93: |
7983f47e |
740 | plug_closing(p->plug, "Proxy error: Username and IDENTD on client don't agree", |
6971bbe7 |
741 | PROXY_ERROR_GENERAL, 0); |
742 | break; |
743 | case 91: |
744 | default: |
7983f47e |
745 | plug_closing(p->plug, "Proxy error: Error while communicating with proxy", |
6971bbe7 |
746 | PROXY_ERROR_GENERAL, 0); |
747 | break; |
748 | } |
749 | |
750 | return 1; |
751 | } |
7983f47e |
752 | bufchain_consume(&p->pending_input_data, 8); |
6971bbe7 |
753 | |
754 | /* we're done */ |
755 | proxy_activate(p); |
756 | /* proxy activate will have dealt with |
757 | * whatever is left of the buffer */ |
758 | return 1; |
759 | } |
760 | } |
761 | |
7983f47e |
762 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
6971bbe7 |
763 | PROXY_ERROR_UNEXPECTED, 0); |
764 | return 1; |
765 | } |
766 | |
767 | /* SOCKS version 5 */ |
768 | int proxy_socks5_negotiate (Proxy_Socket p, int change) |
769 | { |
770 | if (p->state == PROXY_CHANGE_NEW) { |
771 | |
772 | /* initial command: |
773 | * version number (1 byte) = 5 |
774 | * number of available authentication methods (1 byte) |
775 | * available authentication methods (1 byte * previous value) |
776 | * authentication methods: |
777 | * 0x00 = no authentication |
778 | * 0x01 = GSSAPI |
779 | * 0x02 = username/password |
780 | * 0x03 = CHAP |
781 | */ |
782 | |
aab91a3e |
783 | char command[4]; |
784 | int len; |
6971bbe7 |
785 | |
786 | command[0] = 5; /* version 5 */ |
aab91a3e |
787 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
788 | command[1] = 2; /* two methods supported: */ |
789 | command[2] = 0x00; /* no authentication */ |
790 | command[3] = 0x02; /* username/password */ |
791 | len = 4; |
792 | } else { |
793 | command[1] = 1; /* one methods supported: */ |
794 | command[2] = 0x00; /* no authentication */ |
795 | len = 3; |
796 | } |
6971bbe7 |
797 | |
aab91a3e |
798 | sk_write(p->sub_socket, command, len); |
6971bbe7 |
799 | |
800 | p->state = 1; |
801 | return 0; |
802 | } |
803 | |
804 | if (change == PROXY_CHANGE_CLOSING) { |
805 | /* if our proxy negotiation process involves closing and opening |
806 | * new sockets, then we would want to intercept this closing |
807 | * callback when we were expecting it. if we aren't anticipating |
808 | * a socket close, then some error must have occurred. we'll |
809 | * just pass those errors up to the backend. |
810 | */ |
811 | return plug_closing(p->plug, p->closing_error_msg, |
812 | p->closing_error_code, |
813 | p->closing_calling_back); |
814 | } |
815 | |
816 | if (change == PROXY_CHANGE_SENT) { |
817 | /* some (or all) of what we wrote to the proxy was sent. |
818 | * we don't do anything new, however, until we receive the |
819 | * proxy's response. we might want to set a timer so we can |
820 | * timeout the proxy negotiation after a while... |
821 | */ |
822 | return 0; |
823 | } |
824 | |
825 | if (change == PROXY_CHANGE_ACCEPTING) { |
826 | /* we should _never_ see this, as we are using our socket to |
827 | * connect to a proxy, not accepting inbound connections. |
828 | * what should we do? close the socket with an appropriate |
829 | * error message? |
830 | */ |
831 | return plug_accepting(p->plug, p->accepting_sock); |
832 | } |
833 | |
834 | if (change == PROXY_CHANGE_RECEIVE) { |
835 | /* we have received data from the underlying socket, which |
836 | * we'll need to parse, process, and respond to appropriately. |
837 | */ |
838 | |
6971bbe7 |
839 | if (p->state == 1) { |
840 | |
841 | /* initial response: |
842 | * version number (1 byte) = 5 |
843 | * authentication method (1 byte) |
844 | * authentication methods: |
845 | * 0x00 = no authentication |
846 | * 0x01 = GSSAPI |
847 | * 0x02 = username/password |
848 | * 0x03 = CHAP |
849 | * 0xff = no acceptable methods |
850 | */ |
7983f47e |
851 | char data[2]; |
852 | |
853 | if (bufchain_size(&p->pending_input_data) < 2) |
854 | return 1; /* not got anything yet */ |
6971bbe7 |
855 | |
856 | /* get the response */ |
7983f47e |
857 | bufchain_fetch(&p->pending_input_data, data, 2); |
6971bbe7 |
858 | |
859 | if (data[0] != 5) { |
7983f47e |
860 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned unexpected version", |
6971bbe7 |
861 | PROXY_ERROR_GENERAL, 0); |
862 | return 1; |
863 | } |
864 | |
865 | if (data[1] == 0x00) p->state = 2; /* no authentication needed */ |
866 | else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */ |
867 | else if (data[1] == 0x02) p->state = 5; /* username/password authentication */ |
868 | else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */ |
869 | else { |
7983f47e |
870 | plug_closing(p->plug, "Proxy error: SOCKS proxy did not accept our authentication", |
6971bbe7 |
871 | PROXY_ERROR_GENERAL, 0); |
872 | return 1; |
873 | } |
aab91a3e |
874 | bufchain_consume(&p->pending_input_data, 2); |
875 | } |
876 | |
877 | if (p->state == 7) { |
878 | |
879 | /* password authentication reply format: |
880 | * version number (1 bytes) = 1 |
881 | * reply code (1 byte) |
882 | * 0 = succeeded |
883 | * >0 = failed |
884 | */ |
7983f47e |
885 | char data[2]; |
886 | |
887 | if (bufchain_size(&p->pending_input_data) < 2) |
888 | return 1; /* not got anything yet */ |
aab91a3e |
889 | |
890 | /* get the response */ |
7983f47e |
891 | bufchain_fetch(&p->pending_input_data, data, 2); |
aab91a3e |
892 | |
893 | if (data[0] != 1) { |
7983f47e |
894 | plug_closing(p->plug, "Proxy error: SOCKS password " |
895 | "subnegotiation contained wrong version number", |
aab91a3e |
896 | PROXY_ERROR_GENERAL, 0); |
897 | return 1; |
898 | } |
899 | |
900 | if (data[1] != 0) { |
901 | |
7983f47e |
902 | plug_closing(p->plug, "Proxy error: SOCKS proxy refused" |
903 | " password authentication", |
aab91a3e |
904 | PROXY_ERROR_GENERAL, 0); |
905 | return 1; |
906 | } |
907 | |
908 | bufchain_consume(&p->pending_input_data, 2); |
909 | p->state = 2; /* now proceed as authenticated */ |
6971bbe7 |
910 | } |
911 | |
912 | if (p->state == 2) { |
913 | |
914 | /* request format: |
915 | * version number (1 byte) = 5 |
916 | * command code (1 byte) |
917 | * 1 = CONNECT |
918 | * 2 = BIND |
919 | * 3 = UDP ASSOCIATE |
920 | * reserved (1 byte) = 0x00 |
921 | * address type (1 byte) |
922 | * 1 = IPv4 |
923 | * 3 = domainname (first byte has length, no terminating null) |
924 | * 4 = IPv6 |
925 | * dest. address (variable) |
926 | * dest. port (2 bytes) [network order] |
927 | */ |
928 | |
929 | char command[22]; |
930 | int len; |
931 | |
68a49acb |
932 | if (sk_addrtype(p->remote_addr) == ADDRTYPE_IPV6) { |
6971bbe7 |
933 | len = 10; |
934 | command[3] = 1; /* IPv4 */ |
935 | } else { |
936 | len = 22; |
937 | command[3] = 4; /* IPv6 */ |
938 | } |
939 | |
940 | command[0] = 5; /* version 5 */ |
941 | command[1] = 1; /* CONNECT command */ |
942 | command[2] = 0x00; |
943 | |
944 | /* address */ |
945 | sk_addrcopy(p->remote_addr, command+4); |
946 | |
947 | /* port */ |
948 | command[len-2] = (char) (p->remote_port >> 8) & 0xff; |
949 | command[len-1] = (char) p->remote_port & 0xff; |
950 | |
951 | sk_write(p->sub_socket, command, len); |
952 | |
953 | p->state = 3; |
954 | return 1; |
955 | } |
956 | |
957 | if (p->state == 3) { |
958 | |
959 | /* reply format: |
960 | * version number (1 bytes) = 5 |
961 | * reply code (1 byte) |
962 | * 0 = succeeded |
963 | * 1 = general SOCKS server failure |
964 | * 2 = connection not allowed by ruleset |
965 | * 3 = network unreachable |
966 | * 4 = host unreachable |
967 | * 5 = connection refused |
968 | * 6 = TTL expired |
969 | * 7 = command not supported |
970 | * 8 = address type not supported |
971 | * reserved (1 byte) = x00 |
972 | * address type (1 byte) |
973 | * 1 = IPv4 |
974 | * 3 = domainname (first byte has length, no terminating null) |
975 | * 4 = IPv6 |
976 | * server bound address (variable) |
977 | * server bound port (2 bytes) [network order] |
978 | */ |
7983f47e |
979 | char data[5]; |
980 | int len; |
981 | |
982 | /* First 5 bytes of packet are enough to tell its length. */ |
983 | if (bufchain_size(&p->pending_input_data) < 5) |
984 | return 1; /* not got anything yet */ |
6971bbe7 |
985 | |
986 | /* get the response */ |
7983f47e |
987 | bufchain_fetch(&p->pending_input_data, data, 5); |
6971bbe7 |
988 | |
989 | if (data[0] != 5) { |
7983f47e |
990 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned wrong version number", |
6971bbe7 |
991 | PROXY_ERROR_GENERAL, 0); |
992 | return 1; |
993 | } |
994 | |
995 | if (data[1] != 0) { |
7983f47e |
996 | char buf[256]; |
997 | |
998 | strcpy(buf, "Proxy error: "); |
6971bbe7 |
999 | |
1000 | switch (data[1]) { |
7983f47e |
1001 | case 1: strcat(buf, "General SOCKS server failure"); break; |
1002 | case 2: strcat(buf, "Connection not allowed by ruleset"); break; |
1003 | case 3: strcat(buf, "Network unreachable"); break; |
1004 | case 4: strcat(buf, "Host unreachable"); break; |
1005 | case 5: strcat(buf, "Connection refused"); break; |
1006 | case 6: strcat(buf, "TTL expired"); break; |
1007 | case 7: strcat(buf, "Command not supported"); break; |
1008 | case 8: strcat(buf, "Address type not supported"); break; |
1009 | default: sprintf(buf+strlen(buf), |
1010 | "Unrecognised SOCKS error code %d", |
1011 | data[1]); |
6971bbe7 |
1012 | break; |
1013 | } |
7983f47e |
1014 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
1015 | |
1016 | return 1; |
1017 | } |
6971bbe7 |
1018 | |
7983f47e |
1019 | /* |
1020 | * Eat the rest of the reply packet. |
1021 | */ |
1022 | len = 6; /* first 4 bytes, last 2 */ |
1023 | switch (data[3]) { |
1024 | case 1: len += 4; break; /* IPv4 address */ |
1025 | case 4: len += 16; break;/* IPv6 address */ |
1026 | case 3: len += (unsigned char)data[4]; break; /* domain name */ |
1027 | default: |
1028 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned " |
1029 | "unrecognised address format", |
1030 | PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
1031 | return 1; |
1032 | } |
7983f47e |
1033 | if (bufchain_size(&p->pending_input_data) < len) |
1034 | return 1; /* not got whole reply yet */ |
1035 | bufchain_consume(&p->pending_input_data, len); |
6971bbe7 |
1036 | |
1037 | /* we're done */ |
1038 | proxy_activate(p); |
6971bbe7 |
1039 | return 1; |
1040 | } |
1041 | |
1042 | if (p->state == 4) { |
1043 | /* TODO: Handle GSSAPI authentication */ |
2192a8e4 |
1044 | plug_closing(p->plug, "Proxy error: We don't support GSSAPI authentication", |
6971bbe7 |
1045 | PROXY_ERROR_GENERAL, 0); |
1046 | return 1; |
1047 | } |
1048 | |
1049 | if (p->state == 5) { |
aab91a3e |
1050 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
1051 | char userpwbuf[514]; |
1052 | int ulen, plen; |
1053 | ulen = strlen(cfg.proxy_username); |
1054 | if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1; |
1055 | plen = strlen(cfg.proxy_password); |
1056 | if (plen > 255) plen = 255; if (plen < 1) plen = 1; |
1057 | userpwbuf[0] = 1; /* version number of subnegotiation */ |
1058 | userpwbuf[1] = ulen; |
1059 | memcpy(userpwbuf+2, cfg.proxy_username, ulen); |
1060 | userpwbuf[ulen+2] = plen; |
1061 | memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen); |
1062 | sk_write(p->sub_socket, userpwbuf, ulen + plen + 3); |
1063 | p->state = 7; |
1064 | } else |
2192a8e4 |
1065 | plug_closing(p->plug, "Proxy error: Server chose " |
aab91a3e |
1066 | "username/password authentication but we " |
1067 | "didn't offer it!", |
6971bbe7 |
1068 | PROXY_ERROR_GENERAL, 0); |
1069 | return 1; |
1070 | } |
1071 | |
1072 | if (p->state == 6) { |
1073 | /* TODO: Handle CHAP authentication */ |
2192a8e4 |
1074 | plug_closing(p->plug, "Proxy error: We don't support CHAP authentication", |
6971bbe7 |
1075 | PROXY_ERROR_GENERAL, 0); |
1076 | return 1; |
1077 | } |
aab91a3e |
1078 | |
6971bbe7 |
1079 | } |
1080 | |
2192a8e4 |
1081 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
6971bbe7 |
1082 | PROXY_ERROR_UNEXPECTED, 0); |
1083 | return 1; |
8eebd221 |
1084 | } |
1085 | |
1086 | /* ---------------------------------------------------------------------- |
0e8f4cda |
1087 | * `Telnet' proxy type. |
8eebd221 |
1088 | * |
1089 | * (This is for ad-hoc proxies where you connect to the proxy's |
1090 | * telnet port and send a command such as `connect host port'. The |
1091 | * command is configurable, since this proxy type is typically not |
1092 | * standardised or at all well-defined.) |
1093 | */ |
1094 | |
1095 | int proxy_telnet_negotiate (Proxy_Socket p, int change) |
1096 | { |
0e8f4cda |
1097 | if (p->state == PROXY_CHANGE_NEW) { |
1098 | |
1099 | int so = 0, eo = 0; |
1100 | |
1101 | /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, |
2d129d8e |
1102 | * %%, %host, %port, %user, and %pass |
0e8f4cda |
1103 | */ |
1104 | |
1105 | while (cfg.proxy_telnet_command[eo] != 0) { |
1106 | |
1107 | /* scan forward until we hit end-of-line, |
1108 | * or an escape character (\ or %) */ |
1109 | while (cfg.proxy_telnet_command[eo] != 0 && |
1110 | cfg.proxy_telnet_command[eo] != '%' && |
1111 | cfg.proxy_telnet_command[eo] != '\\') eo++; |
1112 | |
1113 | /* if we hit eol, break out of our escaping loop */ |
1114 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1115 | |
1116 | /* if there was any unescaped text before the escape |
1117 | * character, send that now */ |
1118 | if (eo != so) { |
1119 | sk_write(p->sub_socket, |
1120 | cfg.proxy_telnet_command + so, eo - so); |
1121 | } |
1122 | |
1123 | so = eo++; |
1124 | |
1125 | /* if the escape character was the last character of |
1126 | * the line, we'll just stop and send it. */ |
1127 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1128 | |
1129 | if (cfg.proxy_telnet_command[so] == '\\') { |
1130 | |
1131 | /* we recognize \\, \%, \r, \n, \t, \x??. |
1132 | * anything else, we just send unescaped (including the \). |
1133 | */ |
1134 | |
1135 | switch (cfg.proxy_telnet_command[eo]) { |
1136 | |
1137 | case '\\': |
1138 | sk_write(p->sub_socket, "\\", 1); |
1139 | eo++; |
1140 | break; |
1141 | |
1142 | case '%': |
1143 | sk_write(p->sub_socket, "%%", 1); |
1144 | eo++; |
1145 | break; |
1146 | |
1147 | case 'r': |
1148 | sk_write(p->sub_socket, "\r", 1); |
1149 | eo++; |
1150 | break; |
1151 | |
1152 | case 'n': |
1153 | sk_write(p->sub_socket, "\n", 1); |
1154 | eo++; |
1155 | break; |
1156 | |
1157 | case 't': |
1158 | sk_write(p->sub_socket, "\t", 1); |
1159 | eo++; |
1160 | break; |
1161 | |
1162 | case 'x': |
1163 | case 'X': |
1164 | { |
1165 | /* escaped hexadecimal value (ie. \xff) */ |
1166 | unsigned char v = 0; |
1167 | int i = 0; |
1168 | |
1169 | for (;;) { |
1170 | eo++; |
1171 | if (cfg.proxy_telnet_command[eo] >= '0' && |
1172 | cfg.proxy_telnet_command[eo] <= '9') |
1173 | v += cfg.proxy_telnet_command[eo] - '0'; |
1174 | else if (cfg.proxy_telnet_command[eo] >= 'a' && |
1175 | cfg.proxy_telnet_command[eo] <= 'f') |
1176 | v += cfg.proxy_telnet_command[eo] - 'a' + 10; |
1177 | else if (cfg.proxy_telnet_command[eo] >= 'A' && |
1178 | cfg.proxy_telnet_command[eo] <= 'F') |
1179 | v += cfg.proxy_telnet_command[eo] - 'A' + 10; |
1180 | else { |
1181 | /* non hex character, so we abort and just |
1182 | * send the whole thing unescaped (including \x) |
1183 | */ |
1184 | sk_write(p->sub_socket, "\\", 1); |
1185 | eo = so + 1; |
1186 | break; |
1187 | } |
1188 | |
1189 | /* we only extract two hex characters */ |
1190 | if (i == 1) { |
1191 | sk_write(p->sub_socket, &v, 1); |
1192 | eo++; |
1193 | break; |
1194 | } |
1195 | |
1196 | i++; |
1197 | v <<= 4; |
1198 | } |
1199 | } |
1200 | break; |
1201 | |
1202 | default: |
1203 | sk_write(p->sub_socket, |
1204 | cfg.proxy_telnet_command + so, 2); |
1205 | eo++; |
1206 | break; |
1207 | } |
1208 | } else { |
1209 | |
2d129d8e |
1210 | /* % escape. we recognize %%, %host, %port, %user, %pass. |
1211 | * anything else, we just send unescaped (including the %). |
1212 | */ |
0e8f4cda |
1213 | |
1214 | if (cfg.proxy_telnet_command[eo] == '%') { |
1215 | sk_write(p->sub_socket, "%", 1); |
1216 | eo++; |
2d129d8e |
1217 | } |
0e8f4cda |
1218 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1219 | "host", 4) == 0) { |
1220 | char dest[64]; |
1221 | sk_getaddr(p->remote_addr, dest, 64); |
1222 | sk_write(p->sub_socket, dest, strlen(dest)); |
1223 | eo += 4; |
2d129d8e |
1224 | } |
0e8f4cda |
1225 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1226 | "port", 4) == 0) { |
1227 | char port[8]; |
1228 | sprintf(port, "%i", p->remote_port); |
1229 | sk_write(p->sub_socket, port, strlen(port)); |
1230 | eo += 4; |
2d129d8e |
1231 | } |
1232 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1233 | "user", 4) == 0) { |
1234 | sk_write(p->sub_socket, cfg.proxy_username, |
1235 | strlen(cfg.proxy_username)); |
1236 | eo += 4; |
1237 | } |
1238 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1239 | "pass", 4) == 0) { |
1240 | sk_write(p->sub_socket, cfg.proxy_password, |
1241 | strlen(cfg.proxy_password)); |
1242 | eo += 4; |
1243 | } |
0e8f4cda |
1244 | else { |
1245 | /* we don't escape this, so send the % now, and |
1246 | * don't advance eo, so that we'll consider the |
1247 | * text immediately following the % as unescaped. |
1248 | */ |
1249 | sk_write(p->sub_socket, "%", 1); |
1250 | } |
1251 | } |
1252 | |
1253 | /* resume scanning for additional escapes after this one. */ |
1254 | so = eo; |
1255 | } |
1256 | |
1257 | /* if there is any unescaped text at the end of the line, send it */ |
1258 | if (eo != so) { |
1259 | sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); |
1260 | } |
1261 | |
1262 | p->state = 1; |
0e8f4cda |
1263 | return 0; |
1264 | } |
1265 | |
1266 | if (change == PROXY_CHANGE_CLOSING) { |
1267 | /* if our proxy negotiation process involves closing and opening |
1268 | * new sockets, then we would want to intercept this closing |
1269 | * callback when we were expecting it. if we aren't anticipating |
1270 | * a socket close, then some error must have occurred. we'll |
1271 | * just pass those errors up to the backend. |
1272 | */ |
1273 | return plug_closing(p->plug, p->closing_error_msg, |
1274 | p->closing_error_code, |
1275 | p->closing_calling_back); |
1276 | } |
1277 | |
1278 | if (change == PROXY_CHANGE_SENT) { |
1279 | /* some (or all) of what we wrote to the proxy was sent. |
1280 | * we don't do anything new, however, until we receive the |
1281 | * proxy's response. we might want to set a timer so we can |
1282 | * timeout the proxy negotiation after a while... |
1283 | */ |
1284 | return 0; |
1285 | } |
1286 | |
1287 | if (change == PROXY_CHANGE_ACCEPTING) { |
1288 | /* we should _never_ see this, as we are using our socket to |
1289 | * connect to a proxy, not accepting inbound connections. |
1290 | * what should we do? close the socket with an appropriate |
1291 | * error message? |
1292 | */ |
1293 | return plug_accepting(p->plug, p->accepting_sock); |
1294 | } |
1295 | |
1296 | if (change == PROXY_CHANGE_RECEIVE) { |
1297 | /* we have received data from the underlying socket, which |
1298 | * we'll need to parse, process, and respond to appropriately. |
1299 | */ |
1300 | |
1301 | /* we're done */ |
1302 | proxy_activate(p); |
1303 | /* proxy activate will have dealt with |
1304 | * whatever is left of the buffer */ |
1305 | return 1; |
1306 | } |
1307 | |
2192a8e4 |
1308 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
0e8f4cda |
1309 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
1310 | return 1; |
8eebd221 |
1311 | } |