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 | |
b804e1e5 |
250 | /* |
251 | * Check the host name and IP against the hard-coded |
252 | * representations of `localhost'. |
253 | */ |
254 | if (!cfg.even_proxy_localhost && |
255 | (sk_hostname_is_local(hostname) || sk_address_is_local(addr))) |
256 | return 0; /* do not proxy */ |
257 | |
8eebd221 |
258 | /* we want a string representation of the IP address for comparisons */ |
259 | sk_getaddr(addr, hostip, 64); |
260 | |
261 | hostip_len = strlen(hostip); |
262 | hostname_len = strlen(hostname); |
263 | |
264 | exclude_list = cfg.proxy_exclude_list; |
265 | |
266 | /* now parse the exclude list, and see if either our IP |
267 | * or hostname matches anything in it. |
268 | */ |
269 | |
270 | while (exclude_list[s]) { |
271 | while (exclude_list[s] && |
272 | (isspace(exclude_list[s]) || |
273 | exclude_list[s] == ',')) s++; |
274 | |
275 | if (!exclude_list[s]) break; |
276 | |
277 | e = s; |
278 | |
279 | while (exclude_list[e] && |
280 | (isalnum(exclude_list[e]) || |
281 | exclude_list[e] == '-' || |
282 | exclude_list[e] == '.' || |
283 | exclude_list[e] == '*')) e++; |
284 | |
285 | if (exclude_list[s] == '*') { |
286 | /* wildcard at beginning of entry */ |
287 | |
288 | if (strnicmp(hostip + hostip_len - (e - s - 1), |
289 | exclude_list + s + 1, e - s - 1) == 0 || |
290 | strnicmp(hostname + hostname_len - (e - s - 1), |
291 | exclude_list + s + 1, e - s - 1) == 0) |
292 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
293 | |
294 | } else if (exclude_list[e-1] == '*') { |
295 | /* wildcard at end of entry */ |
296 | |
297 | if (strnicmp(hostip, exclude_list + s, e - s - 1) == 0 || |
298 | strnicmp(hostname, exclude_list + s, e - s - 1) == 0) |
299 | return 0; /* IP/hostname range excluded. do not use proxy. */ |
300 | |
301 | } else { |
302 | /* no wildcard at either end, so let's try an absolute |
303 | * match (ie. a specific IP) |
304 | */ |
305 | |
306 | if (stricmp(hostip, exclude_list + s) == 0) |
307 | return 0; /* IP/hostname excluded. do not use proxy. */ |
308 | if (stricmp(hostname, exclude_list + s) == 0) |
309 | return 0; /* IP/hostname excluded. do not use proxy. */ |
310 | } |
311 | |
312 | s = e; |
313 | } |
314 | |
315 | /* no matches in the exclude list, so use the proxy */ |
316 | return 1; |
317 | } |
318 | |
319 | Socket new_connection(SockAddr addr, char *hostname, |
320 | int port, int privport, |
321 | int oobinline, int nodelay, Plug plug) |
322 | { |
7b6c9b99 |
323 | static const struct socket_function_table socket_fn_table = { |
8eebd221 |
324 | sk_proxy_plug, |
325 | sk_proxy_close, |
326 | sk_proxy_write, |
327 | sk_proxy_write_oob, |
328 | sk_proxy_flush, |
329 | sk_proxy_set_private_ptr, |
330 | sk_proxy_get_private_ptr, |
331 | sk_proxy_set_frozen, |
332 | sk_proxy_socket_error |
333 | }; |
334 | |
7b6c9b99 |
335 | static const struct plug_function_table plug_fn_table = { |
8eebd221 |
336 | plug_proxy_closing, |
337 | plug_proxy_receive, |
338 | plug_proxy_sent, |
339 | plug_proxy_accepting |
340 | }; |
341 | |
342 | if (cfg.proxy_type != PROXY_NONE && |
343 | proxy_for_destination(addr, hostname, port)) |
344 | { |
345 | Proxy_Socket ret; |
346 | Proxy_Plug pplug; |
347 | SockAddr proxy_addr; |
348 | char * proxy_canonical_name; |
349 | |
350 | ret = smalloc(sizeof(struct Socket_proxy_tag)); |
351 | ret->fn = &socket_fn_table; |
352 | ret->plug = plug; |
353 | ret->remote_addr = addr; |
354 | ret->remote_port = port; |
355 | |
65c78e88 |
356 | ret->error = NULL; |
357 | ret->pending_flush = 0; |
358 | ret->freeze = 0; |
359 | |
8eebd221 |
360 | bufchain_init(&ret->pending_input_data); |
361 | bufchain_init(&ret->pending_output_data); |
362 | bufchain_init(&ret->pending_oob_output_data); |
363 | |
8eebd221 |
364 | ret->sub_socket = NULL; |
365 | ret->state = PROXY_STATE_NEW; |
2d129d8e |
366 | ret->negotiate = NULL; |
367 | |
8eebd221 |
368 | if (cfg.proxy_type == PROXY_HTTP) { |
369 | ret->negotiate = proxy_http_negotiate; |
370 | } else if (cfg.proxy_type == PROXY_SOCKS) { |
6971bbe7 |
371 | if (cfg.proxy_socks_version == 4) |
372 | ret->negotiate = proxy_socks4_negotiate; |
373 | else |
374 | ret->negotiate = proxy_socks5_negotiate; |
8eebd221 |
375 | } else if (cfg.proxy_type == PROXY_TELNET) { |
376 | ret->negotiate = proxy_telnet_negotiate; |
377 | } else { |
7983f47e |
378 | ret->error = "Proxy error: Unknown proxy method"; |
8eebd221 |
379 | return (Socket) ret; |
380 | } |
381 | |
382 | /* create the proxy plug to map calls from the actual |
383 | * socket into our proxy socket layer */ |
384 | pplug = smalloc(sizeof(struct Plug_proxy_tag)); |
385 | pplug->fn = &plug_fn_table; |
386 | pplug->proxy_socket = ret; |
387 | |
388 | /* look-up proxy */ |
389 | proxy_addr = sk_namelookup(cfg.proxy_host, |
390 | &proxy_canonical_name); |
391 | sfree(proxy_canonical_name); |
392 | |
393 | /* create the actual socket we will be using, |
394 | * connected to our proxy server and port. |
395 | */ |
396 | ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port, |
397 | privport, oobinline, |
398 | nodelay, (Plug) pplug); |
399 | if (sk_socket_error(ret->sub_socket) != NULL) |
400 | return (Socket) ret; |
401 | |
402 | sk_addr_free(proxy_addr); |
403 | |
404 | /* start the proxy negotiation process... */ |
405 | sk_set_frozen(ret->sub_socket, 0); |
406 | ret->negotiate(ret, PROXY_CHANGE_NEW); |
407 | |
408 | return (Socket) ret; |
409 | } |
410 | |
411 | /* no proxy, so just return the direct socket */ |
412 | return sk_new(addr, port, privport, oobinline, nodelay, plug); |
413 | } |
414 | |
6ee9b735 |
415 | Socket new_listener(char *srcaddr, int port, Plug plug, int local_host_only) |
8eebd221 |
416 | { |
417 | /* TODO: SOCKS (and potentially others) support inbound |
418 | * TODO: connections via the proxy. support them. |
419 | */ |
420 | |
6ee9b735 |
421 | return sk_newlistener(srcaddr, port, plug, local_host_only); |
8eebd221 |
422 | } |
423 | |
424 | /* ---------------------------------------------------------------------- |
425 | * HTTP CONNECT proxy type. |
426 | */ |
427 | |
428 | static int get_line_end (char * data, int len) |
429 | { |
430 | int off = 0; |
431 | |
432 | while (off < len) |
433 | { |
434 | if (data[off] == '\n') { |
435 | /* we have a newline */ |
436 | off++; |
437 | |
438 | /* is that the only thing on this line? */ |
439 | if (off <= 2) return off; |
440 | |
441 | /* if not, then there is the possibility that this header |
442 | * continues onto the next line, if it starts with a space |
443 | * or a tab. |
444 | */ |
445 | |
446 | if (off + 1 < len && |
447 | data[off+1] != ' ' && |
448 | data[off+1] != '\t') return off; |
449 | |
450 | /* the line does continue, so we have to keep going |
451 | * until we see an the header's "real" end of line. |
452 | */ |
453 | off++; |
454 | } |
455 | |
456 | off++; |
457 | } |
458 | |
459 | return -1; |
460 | } |
461 | |
462 | int proxy_http_negotiate (Proxy_Socket p, int change) |
463 | { |
464 | if (p->state == PROXY_STATE_NEW) { |
465 | /* we are just beginning the proxy negotiate process, |
466 | * so we'll send off the initial bits of the request. |
467 | * for this proxy method, it's just a simple HTTP |
468 | * request |
469 | */ |
57356d63 |
470 | char *buf, dest[64]; |
8eebd221 |
471 | |
0e8f4cda |
472 | sk_getaddr(p->remote_addr, dest, 64); |
8eebd221 |
473 | |
57356d63 |
474 | buf = dupprintf("CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n", |
475 | dest, p->remote_port, dest, p->remote_port); |
8eebd221 |
476 | sk_write(p->sub_socket, buf, strlen(buf)); |
57356d63 |
477 | sfree(buf); |
8eebd221 |
478 | |
1549e076 |
479 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
480 | char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)]; |
481 | char buf2[sizeof(buf)*4/3 + 100]; |
482 | int i, j, len; |
483 | sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password); |
484 | len = strlen(buf); |
485 | sprintf(buf2, "Proxy-Authorization: basic "); |
486 | for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4) |
487 | base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j); |
488 | strcpy(buf2+j, "\r\n"); |
489 | sk_write(p->sub_socket, buf2, strlen(buf2)); |
490 | } |
491 | |
9ddf18a4 |
492 | sk_write(p->sub_socket, "\r\n", 2); |
1549e076 |
493 | |
8eebd221 |
494 | p->state = 1; |
8eebd221 |
495 | return 0; |
496 | } |
497 | |
498 | if (change == PROXY_CHANGE_CLOSING) { |
499 | /* if our proxy negotiation process involves closing and opening |
500 | * new sockets, then we would want to intercept this closing |
501 | * callback when we were expecting it. if we aren't anticipating |
502 | * a socket close, then some error must have occurred. we'll |
503 | * just pass those errors up to the backend. |
504 | */ |
505 | return plug_closing(p->plug, p->closing_error_msg, |
506 | p->closing_error_code, |
507 | p->closing_calling_back); |
508 | } |
509 | |
510 | if (change == PROXY_CHANGE_SENT) { |
511 | /* some (or all) of what we wrote to the proxy was sent. |
512 | * we don't do anything new, however, until we receive the |
513 | * proxy's response. we might want to set a timer so we can |
514 | * timeout the proxy negotiation after a while... |
515 | */ |
516 | return 0; |
517 | } |
518 | |
519 | if (change == PROXY_CHANGE_ACCEPTING) { |
520 | /* we should _never_ see this, as we are using our socket to |
521 | * connect to a proxy, not accepting inbound connections. |
522 | * what should we do? close the socket with an appropriate |
523 | * error message? |
524 | */ |
525 | return plug_accepting(p->plug, p->accepting_sock); |
526 | } |
527 | |
528 | if (change == PROXY_CHANGE_RECEIVE) { |
529 | /* we have received data from the underlying socket, which |
530 | * we'll need to parse, process, and respond to appropriately. |
531 | */ |
532 | |
7983f47e |
533 | char *data, *datap; |
8eebd221 |
534 | int len; |
535 | int eol; |
536 | |
537 | if (p->state == 1) { |
538 | |
539 | int min_ver, maj_ver, status; |
540 | |
541 | /* get the status line */ |
7983f47e |
542 | len = bufchain_size(&p->pending_input_data); |
543 | assert(len > 0); /* or we wouldn't be here */ |
544 | data = smalloc(len); |
545 | bufchain_fetch(&p->pending_input_data, data, len); |
546 | |
8eebd221 |
547 | eol = get_line_end(data, len); |
7983f47e |
548 | if (eol < 0) { |
549 | sfree(data); |
550 | return 1; |
551 | } |
8eebd221 |
552 | |
7983f47e |
553 | status = -1; |
554 | /* We can't rely on whether the %n incremented the sscanf return */ |
555 | if (sscanf((char *)data, "HTTP/%i.%i %n", |
556 | &maj_ver, &min_ver, &status) < 2 || status == -1) { |
557 | plug_closing(p->plug, "Proxy error: HTTP response was absent", |
558 | PROXY_ERROR_GENERAL, 0); |
559 | sfree(data); |
560 | return 1; |
561 | } |
8eebd221 |
562 | |
563 | /* remove the status line from the input buffer. */ |
564 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
565 | if (data[status] != '2') { |
8eebd221 |
566 | /* error */ |
57356d63 |
567 | char *buf; |
7983f47e |
568 | data[eol] = '\0'; |
569 | while (eol > status && |
570 | (data[eol-1] == '\r' || data[eol-1] == '\n')) |
571 | data[--eol] = '\0'; |
57356d63 |
572 | buf = dupprintf("Proxy error: %s", data+status); |
7983f47e |
573 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
57356d63 |
574 | sfree(buf); |
7983f47e |
575 | sfree(data); |
8eebd221 |
576 | return 1; |
577 | } |
578 | |
7983f47e |
579 | sfree(data); |
580 | |
8eebd221 |
581 | p->state = 2; |
582 | } |
583 | |
584 | if (p->state == 2) { |
585 | |
586 | /* get headers. we're done when we get a |
587 | * header of length 2, (ie. just "\r\n") |
588 | */ |
589 | |
7983f47e |
590 | len = bufchain_size(&p->pending_input_data); |
591 | assert(len > 0); /* or we wouldn't be here */ |
592 | data = smalloc(len); |
593 | datap = data; |
594 | bufchain_fetch(&p->pending_input_data, data, len); |
595 | |
596 | eol = get_line_end(datap, len); |
597 | if (eol < 0) { |
598 | sfree(data); |
599 | return 1; |
600 | } |
8eebd221 |
601 | while (eol > 2) |
602 | { |
8eebd221 |
603 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
604 | datap += eol; |
9ddf18a4 |
605 | len -= eol; |
7983f47e |
606 | eol = get_line_end(datap, len); |
8eebd221 |
607 | } |
608 | |
609 | if (eol == 2) { |
610 | /* we're done */ |
611 | bufchain_consume(&p->pending_input_data, 2); |
612 | proxy_activate(p); |
613 | /* proxy activate will have dealt with |
614 | * whatever is left of the buffer */ |
7983f47e |
615 | sfree(data); |
8eebd221 |
616 | return 1; |
617 | } |
618 | |
7983f47e |
619 | sfree(data); |
8eebd221 |
620 | return 1; |
621 | } |
622 | } |
623 | |
7983f47e |
624 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
8eebd221 |
625 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
626 | return 1; |
8eebd221 |
627 | } |
628 | |
629 | /* ---------------------------------------------------------------------- |
6971bbe7 |
630 | * SOCKS proxy type. |
8eebd221 |
631 | */ |
632 | |
6971bbe7 |
633 | /* SOCKS version 4 */ |
634 | int proxy_socks4_negotiate (Proxy_Socket p, int change) |
8eebd221 |
635 | { |
6971bbe7 |
636 | if (p->state == PROXY_CHANGE_NEW) { |
637 | |
638 | /* request format: |
639 | * version number (1 byte) = 4 |
640 | * command code (1 byte) |
641 | * 1 = CONNECT |
642 | * 2 = BIND |
643 | * dest. port (2 bytes) [network order] |
644 | * dest. address (4 bytes) |
645 | * user ID (variable length, null terminated string) |
646 | */ |
647 | |
648 | int length; |
649 | char * command; |
650 | |
68a49acb |
651 | if (sk_addrtype(p->remote_addr) != ADDRTYPE_IPV4) { |
7983f47e |
652 | plug_closing(p->plug, "Proxy error: SOCKS version 4 does" |
653 | " not support IPv6", PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
654 | return 1; |
655 | } |
656 | |
657 | length = strlen(cfg.proxy_username) + 9; |
de9aaffb |
658 | command = (char*) smalloc(length); |
6971bbe7 |
659 | strcpy(command + 8, cfg.proxy_username); |
660 | |
661 | command[0] = 4; /* version 4 */ |
662 | command[1] = 1; /* CONNECT command */ |
663 | |
664 | /* port */ |
665 | command[2] = (char) (p->remote_port >> 8) & 0xff; |
666 | command[3] = (char) p->remote_port & 0xff; |
667 | |
668 | /* address */ |
669 | sk_addrcopy(p->remote_addr, command + 4); |
670 | |
671 | sk_write(p->sub_socket, command, length); |
de9aaffb |
672 | sfree(command); |
6971bbe7 |
673 | |
674 | p->state = 1; |
675 | return 0; |
676 | } |
677 | |
678 | if (change == PROXY_CHANGE_CLOSING) { |
679 | /* if our proxy negotiation process involves closing and opening |
680 | * new sockets, then we would want to intercept this closing |
681 | * callback when we were expecting it. if we aren't anticipating |
682 | * a socket close, then some error must have occurred. we'll |
683 | * just pass those errors up to the backend. |
684 | */ |
685 | return plug_closing(p->plug, p->closing_error_msg, |
686 | p->closing_error_code, |
687 | p->closing_calling_back); |
688 | } |
689 | |
690 | if (change == PROXY_CHANGE_SENT) { |
691 | /* some (or all) of what we wrote to the proxy was sent. |
692 | * we don't do anything new, however, until we receive the |
693 | * proxy's response. we might want to set a timer so we can |
694 | * timeout the proxy negotiation after a while... |
695 | */ |
696 | return 0; |
697 | } |
698 | |
699 | if (change == PROXY_CHANGE_ACCEPTING) { |
700 | /* we should _never_ see this, as we are using our socket to |
701 | * connect to a proxy, not accepting inbound connections. |
702 | * what should we do? close the socket with an appropriate |
703 | * error message? |
704 | */ |
705 | return plug_accepting(p->plug, p->accepting_sock); |
706 | } |
707 | |
708 | if (change == PROXY_CHANGE_RECEIVE) { |
709 | /* we have received data from the underlying socket, which |
710 | * we'll need to parse, process, and respond to appropriately. |
711 | */ |
712 | |
713 | if (p->state == 1) { |
714 | /* response format: |
715 | * version number (1 byte) = 4 |
716 | * reply code (1 byte) |
717 | * 90 = request granted |
718 | * 91 = request rejected or failed |
719 | * 92 = request rejected due to lack of IDENTD on client |
720 | * 93 = request rejected due to difference in user ID |
721 | * (what we sent vs. what IDENTD said) |
722 | * dest. port (2 bytes) |
723 | * dest. address (4 bytes) |
724 | */ |
725 | |
7983f47e |
726 | char data[8]; |
6971bbe7 |
727 | |
7983f47e |
728 | if (bufchain_size(&p->pending_input_data) < 8) |
729 | return 1; /* not got anything yet */ |
730 | |
6971bbe7 |
731 | /* get the response */ |
7983f47e |
732 | bufchain_fetch(&p->pending_input_data, data, 8); |
6971bbe7 |
733 | |
734 | if (data[0] != 0) { |
7983f47e |
735 | plug_closing(p->plug, "Proxy error: SOCKS proxy responded with " |
6971bbe7 |
736 | "unexpected reply code version", |
737 | PROXY_ERROR_GENERAL, 0); |
738 | return 1; |
739 | } |
740 | |
741 | if (data[1] != 90) { |
742 | |
743 | switch (data[1]) { |
744 | case 92: |
7983f47e |
745 | plug_closing(p->plug, "Proxy error: SOCKS server wanted IDENTD on client", |
6971bbe7 |
746 | PROXY_ERROR_GENERAL, 0); |
747 | break; |
748 | case 93: |
7983f47e |
749 | plug_closing(p->plug, "Proxy error: Username and IDENTD on client don't agree", |
6971bbe7 |
750 | PROXY_ERROR_GENERAL, 0); |
751 | break; |
752 | case 91: |
753 | default: |
7983f47e |
754 | plug_closing(p->plug, "Proxy error: Error while communicating with proxy", |
6971bbe7 |
755 | PROXY_ERROR_GENERAL, 0); |
756 | break; |
757 | } |
758 | |
759 | return 1; |
760 | } |
7983f47e |
761 | bufchain_consume(&p->pending_input_data, 8); |
6971bbe7 |
762 | |
763 | /* we're done */ |
764 | proxy_activate(p); |
765 | /* proxy activate will have dealt with |
766 | * whatever is left of the buffer */ |
767 | return 1; |
768 | } |
769 | } |
770 | |
7983f47e |
771 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
6971bbe7 |
772 | PROXY_ERROR_UNEXPECTED, 0); |
773 | return 1; |
774 | } |
775 | |
776 | /* SOCKS version 5 */ |
777 | int proxy_socks5_negotiate (Proxy_Socket p, int change) |
778 | { |
779 | if (p->state == PROXY_CHANGE_NEW) { |
780 | |
781 | /* initial command: |
782 | * version number (1 byte) = 5 |
783 | * number of available authentication methods (1 byte) |
784 | * available authentication methods (1 byte * previous value) |
785 | * authentication methods: |
786 | * 0x00 = no authentication |
787 | * 0x01 = GSSAPI |
788 | * 0x02 = username/password |
789 | * 0x03 = CHAP |
790 | */ |
791 | |
aab91a3e |
792 | char command[4]; |
793 | int len; |
6971bbe7 |
794 | |
795 | command[0] = 5; /* version 5 */ |
aab91a3e |
796 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
797 | command[1] = 2; /* two methods supported: */ |
798 | command[2] = 0x00; /* no authentication */ |
799 | command[3] = 0x02; /* username/password */ |
800 | len = 4; |
801 | } else { |
802 | command[1] = 1; /* one methods supported: */ |
803 | command[2] = 0x00; /* no authentication */ |
804 | len = 3; |
805 | } |
6971bbe7 |
806 | |
aab91a3e |
807 | sk_write(p->sub_socket, command, len); |
6971bbe7 |
808 | |
809 | p->state = 1; |
810 | return 0; |
811 | } |
812 | |
813 | if (change == PROXY_CHANGE_CLOSING) { |
814 | /* if our proxy negotiation process involves closing and opening |
815 | * new sockets, then we would want to intercept this closing |
816 | * callback when we were expecting it. if we aren't anticipating |
817 | * a socket close, then some error must have occurred. we'll |
818 | * just pass those errors up to the backend. |
819 | */ |
820 | return plug_closing(p->plug, p->closing_error_msg, |
821 | p->closing_error_code, |
822 | p->closing_calling_back); |
823 | } |
824 | |
825 | if (change == PROXY_CHANGE_SENT) { |
826 | /* some (or all) of what we wrote to the proxy was sent. |
827 | * we don't do anything new, however, until we receive the |
828 | * proxy's response. we might want to set a timer so we can |
829 | * timeout the proxy negotiation after a while... |
830 | */ |
831 | return 0; |
832 | } |
833 | |
834 | if (change == PROXY_CHANGE_ACCEPTING) { |
835 | /* we should _never_ see this, as we are using our socket to |
836 | * connect to a proxy, not accepting inbound connections. |
837 | * what should we do? close the socket with an appropriate |
838 | * error message? |
839 | */ |
840 | return plug_accepting(p->plug, p->accepting_sock); |
841 | } |
842 | |
843 | if (change == PROXY_CHANGE_RECEIVE) { |
844 | /* we have received data from the underlying socket, which |
845 | * we'll need to parse, process, and respond to appropriately. |
846 | */ |
847 | |
6971bbe7 |
848 | if (p->state == 1) { |
849 | |
850 | /* initial response: |
851 | * version number (1 byte) = 5 |
852 | * authentication method (1 byte) |
853 | * authentication methods: |
854 | * 0x00 = no authentication |
855 | * 0x01 = GSSAPI |
856 | * 0x02 = username/password |
857 | * 0x03 = CHAP |
858 | * 0xff = no acceptable methods |
859 | */ |
7983f47e |
860 | char data[2]; |
861 | |
862 | if (bufchain_size(&p->pending_input_data) < 2) |
863 | return 1; /* not got anything yet */ |
6971bbe7 |
864 | |
865 | /* get the response */ |
7983f47e |
866 | bufchain_fetch(&p->pending_input_data, data, 2); |
6971bbe7 |
867 | |
868 | if (data[0] != 5) { |
7983f47e |
869 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned unexpected version", |
6971bbe7 |
870 | PROXY_ERROR_GENERAL, 0); |
871 | return 1; |
872 | } |
873 | |
874 | if (data[1] == 0x00) p->state = 2; /* no authentication needed */ |
875 | else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */ |
876 | else if (data[1] == 0x02) p->state = 5; /* username/password authentication */ |
877 | else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */ |
878 | else { |
7983f47e |
879 | plug_closing(p->plug, "Proxy error: SOCKS proxy did not accept our authentication", |
6971bbe7 |
880 | PROXY_ERROR_GENERAL, 0); |
881 | return 1; |
882 | } |
aab91a3e |
883 | bufchain_consume(&p->pending_input_data, 2); |
884 | } |
885 | |
886 | if (p->state == 7) { |
887 | |
888 | /* password authentication reply format: |
889 | * version number (1 bytes) = 1 |
890 | * reply code (1 byte) |
891 | * 0 = succeeded |
892 | * >0 = failed |
893 | */ |
7983f47e |
894 | char data[2]; |
895 | |
896 | if (bufchain_size(&p->pending_input_data) < 2) |
897 | return 1; /* not got anything yet */ |
aab91a3e |
898 | |
899 | /* get the response */ |
7983f47e |
900 | bufchain_fetch(&p->pending_input_data, data, 2); |
aab91a3e |
901 | |
902 | if (data[0] != 1) { |
7983f47e |
903 | plug_closing(p->plug, "Proxy error: SOCKS password " |
904 | "subnegotiation contained wrong version number", |
aab91a3e |
905 | PROXY_ERROR_GENERAL, 0); |
906 | return 1; |
907 | } |
908 | |
909 | if (data[1] != 0) { |
910 | |
7983f47e |
911 | plug_closing(p->plug, "Proxy error: SOCKS proxy refused" |
912 | " password authentication", |
aab91a3e |
913 | PROXY_ERROR_GENERAL, 0); |
914 | return 1; |
915 | } |
916 | |
917 | bufchain_consume(&p->pending_input_data, 2); |
918 | p->state = 2; /* now proceed as authenticated */ |
6971bbe7 |
919 | } |
920 | |
921 | if (p->state == 2) { |
922 | |
923 | /* request format: |
924 | * version number (1 byte) = 5 |
925 | * command code (1 byte) |
926 | * 1 = CONNECT |
927 | * 2 = BIND |
928 | * 3 = UDP ASSOCIATE |
929 | * reserved (1 byte) = 0x00 |
930 | * address type (1 byte) |
931 | * 1 = IPv4 |
932 | * 3 = domainname (first byte has length, no terminating null) |
933 | * 4 = IPv6 |
934 | * dest. address (variable) |
935 | * dest. port (2 bytes) [network order] |
936 | */ |
937 | |
938 | char command[22]; |
939 | int len; |
940 | |
f74d67ca |
941 | if (sk_addrtype(p->remote_addr) == ADDRTYPE_IPV4) { |
6971bbe7 |
942 | len = 10; |
943 | command[3] = 1; /* IPv4 */ |
944 | } else { |
945 | len = 22; |
946 | command[3] = 4; /* IPv6 */ |
947 | } |
948 | |
949 | command[0] = 5; /* version 5 */ |
950 | command[1] = 1; /* CONNECT command */ |
951 | command[2] = 0x00; |
952 | |
953 | /* address */ |
954 | sk_addrcopy(p->remote_addr, command+4); |
955 | |
956 | /* port */ |
957 | command[len-2] = (char) (p->remote_port >> 8) & 0xff; |
958 | command[len-1] = (char) p->remote_port & 0xff; |
959 | |
960 | sk_write(p->sub_socket, command, len); |
961 | |
962 | p->state = 3; |
963 | return 1; |
964 | } |
965 | |
966 | if (p->state == 3) { |
967 | |
968 | /* reply format: |
969 | * version number (1 bytes) = 5 |
970 | * reply code (1 byte) |
971 | * 0 = succeeded |
972 | * 1 = general SOCKS server failure |
973 | * 2 = connection not allowed by ruleset |
974 | * 3 = network unreachable |
975 | * 4 = host unreachable |
976 | * 5 = connection refused |
977 | * 6 = TTL expired |
978 | * 7 = command not supported |
979 | * 8 = address type not supported |
980 | * reserved (1 byte) = x00 |
981 | * address type (1 byte) |
982 | * 1 = IPv4 |
983 | * 3 = domainname (first byte has length, no terminating null) |
984 | * 4 = IPv6 |
985 | * server bound address (variable) |
986 | * server bound port (2 bytes) [network order] |
987 | */ |
7983f47e |
988 | char data[5]; |
989 | int len; |
990 | |
991 | /* First 5 bytes of packet are enough to tell its length. */ |
992 | if (bufchain_size(&p->pending_input_data) < 5) |
993 | return 1; /* not got anything yet */ |
6971bbe7 |
994 | |
995 | /* get the response */ |
7983f47e |
996 | bufchain_fetch(&p->pending_input_data, data, 5); |
6971bbe7 |
997 | |
998 | if (data[0] != 5) { |
7983f47e |
999 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned wrong version number", |
6971bbe7 |
1000 | PROXY_ERROR_GENERAL, 0); |
1001 | return 1; |
1002 | } |
1003 | |
1004 | if (data[1] != 0) { |
7983f47e |
1005 | char buf[256]; |
1006 | |
1007 | strcpy(buf, "Proxy error: "); |
6971bbe7 |
1008 | |
1009 | switch (data[1]) { |
7983f47e |
1010 | case 1: strcat(buf, "General SOCKS server failure"); break; |
1011 | case 2: strcat(buf, "Connection not allowed by ruleset"); break; |
1012 | case 3: strcat(buf, "Network unreachable"); break; |
1013 | case 4: strcat(buf, "Host unreachable"); break; |
1014 | case 5: strcat(buf, "Connection refused"); break; |
1015 | case 6: strcat(buf, "TTL expired"); break; |
1016 | case 7: strcat(buf, "Command not supported"); break; |
1017 | case 8: strcat(buf, "Address type not supported"); break; |
1018 | default: sprintf(buf+strlen(buf), |
1019 | "Unrecognised SOCKS error code %d", |
1020 | data[1]); |
6971bbe7 |
1021 | break; |
1022 | } |
7983f47e |
1023 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
1024 | |
1025 | return 1; |
1026 | } |
6971bbe7 |
1027 | |
7983f47e |
1028 | /* |
1029 | * Eat the rest of the reply packet. |
1030 | */ |
1031 | len = 6; /* first 4 bytes, last 2 */ |
1032 | switch (data[3]) { |
1033 | case 1: len += 4; break; /* IPv4 address */ |
1034 | case 4: len += 16; break;/* IPv6 address */ |
1035 | case 3: len += (unsigned char)data[4]; break; /* domain name */ |
1036 | default: |
1037 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned " |
1038 | "unrecognised address format", |
1039 | PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
1040 | return 1; |
1041 | } |
7983f47e |
1042 | if (bufchain_size(&p->pending_input_data) < len) |
1043 | return 1; /* not got whole reply yet */ |
1044 | bufchain_consume(&p->pending_input_data, len); |
6971bbe7 |
1045 | |
1046 | /* we're done */ |
1047 | proxy_activate(p); |
6971bbe7 |
1048 | return 1; |
1049 | } |
1050 | |
1051 | if (p->state == 4) { |
1052 | /* TODO: Handle GSSAPI authentication */ |
2192a8e4 |
1053 | plug_closing(p->plug, "Proxy error: We don't support GSSAPI authentication", |
6971bbe7 |
1054 | PROXY_ERROR_GENERAL, 0); |
1055 | return 1; |
1056 | } |
1057 | |
1058 | if (p->state == 5) { |
aab91a3e |
1059 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
1060 | char userpwbuf[514]; |
1061 | int ulen, plen; |
1062 | ulen = strlen(cfg.proxy_username); |
1063 | if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1; |
1064 | plen = strlen(cfg.proxy_password); |
1065 | if (plen > 255) plen = 255; if (plen < 1) plen = 1; |
1066 | userpwbuf[0] = 1; /* version number of subnegotiation */ |
1067 | userpwbuf[1] = ulen; |
1068 | memcpy(userpwbuf+2, cfg.proxy_username, ulen); |
1069 | userpwbuf[ulen+2] = plen; |
1070 | memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen); |
1071 | sk_write(p->sub_socket, userpwbuf, ulen + plen + 3); |
1072 | p->state = 7; |
1073 | } else |
2192a8e4 |
1074 | plug_closing(p->plug, "Proxy error: Server chose " |
aab91a3e |
1075 | "username/password authentication but we " |
1076 | "didn't offer it!", |
6971bbe7 |
1077 | PROXY_ERROR_GENERAL, 0); |
1078 | return 1; |
1079 | } |
1080 | |
1081 | if (p->state == 6) { |
1082 | /* TODO: Handle CHAP authentication */ |
2192a8e4 |
1083 | plug_closing(p->plug, "Proxy error: We don't support CHAP authentication", |
6971bbe7 |
1084 | PROXY_ERROR_GENERAL, 0); |
1085 | return 1; |
1086 | } |
aab91a3e |
1087 | |
6971bbe7 |
1088 | } |
1089 | |
2192a8e4 |
1090 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
6971bbe7 |
1091 | PROXY_ERROR_UNEXPECTED, 0); |
1092 | return 1; |
8eebd221 |
1093 | } |
1094 | |
1095 | /* ---------------------------------------------------------------------- |
0e8f4cda |
1096 | * `Telnet' proxy type. |
8eebd221 |
1097 | * |
1098 | * (This is for ad-hoc proxies where you connect to the proxy's |
1099 | * telnet port and send a command such as `connect host port'. The |
1100 | * command is configurable, since this proxy type is typically not |
1101 | * standardised or at all well-defined.) |
1102 | */ |
1103 | |
1104 | int proxy_telnet_negotiate (Proxy_Socket p, int change) |
1105 | { |
0e8f4cda |
1106 | if (p->state == PROXY_CHANGE_NEW) { |
1107 | |
1108 | int so = 0, eo = 0; |
1109 | |
1110 | /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, |
2d129d8e |
1111 | * %%, %host, %port, %user, and %pass |
0e8f4cda |
1112 | */ |
1113 | |
1114 | while (cfg.proxy_telnet_command[eo] != 0) { |
1115 | |
1116 | /* scan forward until we hit end-of-line, |
1117 | * or an escape character (\ or %) */ |
1118 | while (cfg.proxy_telnet_command[eo] != 0 && |
1119 | cfg.proxy_telnet_command[eo] != '%' && |
1120 | cfg.proxy_telnet_command[eo] != '\\') eo++; |
1121 | |
1122 | /* if we hit eol, break out of our escaping loop */ |
1123 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1124 | |
1125 | /* if there was any unescaped text before the escape |
1126 | * character, send that now */ |
1127 | if (eo != so) { |
1128 | sk_write(p->sub_socket, |
1129 | cfg.proxy_telnet_command + so, eo - so); |
1130 | } |
1131 | |
1132 | so = eo++; |
1133 | |
1134 | /* if the escape character was the last character of |
1135 | * the line, we'll just stop and send it. */ |
1136 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1137 | |
1138 | if (cfg.proxy_telnet_command[so] == '\\') { |
1139 | |
1140 | /* we recognize \\, \%, \r, \n, \t, \x??. |
1141 | * anything else, we just send unescaped (including the \). |
1142 | */ |
1143 | |
1144 | switch (cfg.proxy_telnet_command[eo]) { |
1145 | |
1146 | case '\\': |
1147 | sk_write(p->sub_socket, "\\", 1); |
1148 | eo++; |
1149 | break; |
1150 | |
1151 | case '%': |
1152 | sk_write(p->sub_socket, "%%", 1); |
1153 | eo++; |
1154 | break; |
1155 | |
1156 | case 'r': |
1157 | sk_write(p->sub_socket, "\r", 1); |
1158 | eo++; |
1159 | break; |
1160 | |
1161 | case 'n': |
1162 | sk_write(p->sub_socket, "\n", 1); |
1163 | eo++; |
1164 | break; |
1165 | |
1166 | case 't': |
1167 | sk_write(p->sub_socket, "\t", 1); |
1168 | eo++; |
1169 | break; |
1170 | |
1171 | case 'x': |
1172 | case 'X': |
1173 | { |
1174 | /* escaped hexadecimal value (ie. \xff) */ |
1175 | unsigned char v = 0; |
1176 | int i = 0; |
1177 | |
1178 | for (;;) { |
1179 | eo++; |
1180 | if (cfg.proxy_telnet_command[eo] >= '0' && |
1181 | cfg.proxy_telnet_command[eo] <= '9') |
1182 | v += cfg.proxy_telnet_command[eo] - '0'; |
1183 | else if (cfg.proxy_telnet_command[eo] >= 'a' && |
1184 | cfg.proxy_telnet_command[eo] <= 'f') |
1185 | v += cfg.proxy_telnet_command[eo] - 'a' + 10; |
1186 | else if (cfg.proxy_telnet_command[eo] >= 'A' && |
1187 | cfg.proxy_telnet_command[eo] <= 'F') |
1188 | v += cfg.proxy_telnet_command[eo] - 'A' + 10; |
1189 | else { |
1190 | /* non hex character, so we abort and just |
1191 | * send the whole thing unescaped (including \x) |
1192 | */ |
1193 | sk_write(p->sub_socket, "\\", 1); |
1194 | eo = so + 1; |
1195 | break; |
1196 | } |
1197 | |
1198 | /* we only extract two hex characters */ |
1199 | if (i == 1) { |
1200 | sk_write(p->sub_socket, &v, 1); |
1201 | eo++; |
1202 | break; |
1203 | } |
1204 | |
1205 | i++; |
1206 | v <<= 4; |
1207 | } |
1208 | } |
1209 | break; |
1210 | |
1211 | default: |
1212 | sk_write(p->sub_socket, |
1213 | cfg.proxy_telnet_command + so, 2); |
1214 | eo++; |
1215 | break; |
1216 | } |
1217 | } else { |
1218 | |
2d129d8e |
1219 | /* % escape. we recognize %%, %host, %port, %user, %pass. |
1220 | * anything else, we just send unescaped (including the %). |
1221 | */ |
0e8f4cda |
1222 | |
1223 | if (cfg.proxy_telnet_command[eo] == '%') { |
1224 | sk_write(p->sub_socket, "%", 1); |
1225 | eo++; |
2d129d8e |
1226 | } |
0e8f4cda |
1227 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1228 | "host", 4) == 0) { |
1229 | char dest[64]; |
1230 | sk_getaddr(p->remote_addr, dest, 64); |
1231 | sk_write(p->sub_socket, dest, strlen(dest)); |
1232 | eo += 4; |
2d129d8e |
1233 | } |
0e8f4cda |
1234 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1235 | "port", 4) == 0) { |
1236 | char port[8]; |
1237 | sprintf(port, "%i", p->remote_port); |
1238 | sk_write(p->sub_socket, port, strlen(port)); |
1239 | eo += 4; |
2d129d8e |
1240 | } |
1241 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1242 | "user", 4) == 0) { |
1243 | sk_write(p->sub_socket, cfg.proxy_username, |
1244 | strlen(cfg.proxy_username)); |
1245 | eo += 4; |
1246 | } |
1247 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1248 | "pass", 4) == 0) { |
1249 | sk_write(p->sub_socket, cfg.proxy_password, |
1250 | strlen(cfg.proxy_password)); |
1251 | eo += 4; |
1252 | } |
0e8f4cda |
1253 | else { |
1254 | /* we don't escape this, so send the % now, and |
1255 | * don't advance eo, so that we'll consider the |
1256 | * text immediately following the % as unescaped. |
1257 | */ |
1258 | sk_write(p->sub_socket, "%", 1); |
1259 | } |
1260 | } |
1261 | |
1262 | /* resume scanning for additional escapes after this one. */ |
1263 | so = eo; |
1264 | } |
1265 | |
1266 | /* if there is any unescaped text at the end of the line, send it */ |
1267 | if (eo != so) { |
1268 | sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); |
1269 | } |
1270 | |
1271 | p->state = 1; |
0e8f4cda |
1272 | return 0; |
1273 | } |
1274 | |
1275 | if (change == PROXY_CHANGE_CLOSING) { |
1276 | /* if our proxy negotiation process involves closing and opening |
1277 | * new sockets, then we would want to intercept this closing |
1278 | * callback when we were expecting it. if we aren't anticipating |
1279 | * a socket close, then some error must have occurred. we'll |
1280 | * just pass those errors up to the backend. |
1281 | */ |
1282 | return plug_closing(p->plug, p->closing_error_msg, |
1283 | p->closing_error_code, |
1284 | p->closing_calling_back); |
1285 | } |
1286 | |
1287 | if (change == PROXY_CHANGE_SENT) { |
1288 | /* some (or all) of what we wrote to the proxy was sent. |
1289 | * we don't do anything new, however, until we receive the |
1290 | * proxy's response. we might want to set a timer so we can |
1291 | * timeout the proxy negotiation after a while... |
1292 | */ |
1293 | return 0; |
1294 | } |
1295 | |
1296 | if (change == PROXY_CHANGE_ACCEPTING) { |
1297 | /* we should _never_ see this, as we are using our socket to |
1298 | * connect to a proxy, not accepting inbound connections. |
1299 | * what should we do? close the socket with an appropriate |
1300 | * error message? |
1301 | */ |
1302 | return plug_accepting(p->plug, p->accepting_sock); |
1303 | } |
1304 | |
1305 | if (change == PROXY_CHANGE_RECEIVE) { |
1306 | /* we have received data from the underlying socket, which |
1307 | * we'll need to parse, process, and respond to appropriately. |
1308 | */ |
1309 | |
1310 | /* we're done */ |
1311 | proxy_activate(p); |
1312 | /* proxy activate will have dealt with |
1313 | * whatever is left of the buffer */ |
1314 | return 1; |
1315 | } |
1316 | |
2192a8e4 |
1317 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
0e8f4cda |
1318 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
1319 | return 1; |
8eebd221 |
1320 | } |