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; |
42389a9e |
348 | char *proxy_canonical_name, *err; |
8eebd221 |
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); |
42389a9e |
391 | if ((err = sk_addr_error(proxy_addr))) { |
392 | ret->error = "Proxy error: Unable to resolve proxy host name"; |
393 | return (Socket)ret; |
394 | } |
8eebd221 |
395 | sfree(proxy_canonical_name); |
396 | |
397 | /* create the actual socket we will be using, |
398 | * connected to our proxy server and port. |
399 | */ |
400 | ret->sub_socket = sk_new(proxy_addr, cfg.proxy_port, |
401 | privport, oobinline, |
402 | nodelay, (Plug) pplug); |
403 | if (sk_socket_error(ret->sub_socket) != NULL) |
404 | return (Socket) ret; |
405 | |
406 | sk_addr_free(proxy_addr); |
407 | |
408 | /* start the proxy negotiation process... */ |
409 | sk_set_frozen(ret->sub_socket, 0); |
410 | ret->negotiate(ret, PROXY_CHANGE_NEW); |
411 | |
412 | return (Socket) ret; |
413 | } |
414 | |
415 | /* no proxy, so just return the direct socket */ |
416 | return sk_new(addr, port, privport, oobinline, nodelay, plug); |
417 | } |
418 | |
6ee9b735 |
419 | Socket new_listener(char *srcaddr, int port, Plug plug, int local_host_only) |
8eebd221 |
420 | { |
421 | /* TODO: SOCKS (and potentially others) support inbound |
422 | * TODO: connections via the proxy. support them. |
423 | */ |
424 | |
6ee9b735 |
425 | return sk_newlistener(srcaddr, port, plug, local_host_only); |
8eebd221 |
426 | } |
427 | |
428 | /* ---------------------------------------------------------------------- |
429 | * HTTP CONNECT proxy type. |
430 | */ |
431 | |
432 | static int get_line_end (char * data, int len) |
433 | { |
434 | int off = 0; |
435 | |
436 | while (off < len) |
437 | { |
438 | if (data[off] == '\n') { |
439 | /* we have a newline */ |
440 | off++; |
441 | |
442 | /* is that the only thing on this line? */ |
443 | if (off <= 2) return off; |
444 | |
445 | /* if not, then there is the possibility that this header |
446 | * continues onto the next line, if it starts with a space |
447 | * or a tab. |
448 | */ |
449 | |
450 | if (off + 1 < len && |
451 | data[off+1] != ' ' && |
452 | data[off+1] != '\t') return off; |
453 | |
454 | /* the line does continue, so we have to keep going |
455 | * until we see an the header's "real" end of line. |
456 | */ |
457 | off++; |
458 | } |
459 | |
460 | off++; |
461 | } |
462 | |
463 | return -1; |
464 | } |
465 | |
466 | int proxy_http_negotiate (Proxy_Socket p, int change) |
467 | { |
468 | if (p->state == PROXY_STATE_NEW) { |
469 | /* we are just beginning the proxy negotiate process, |
470 | * so we'll send off the initial bits of the request. |
471 | * for this proxy method, it's just a simple HTTP |
472 | * request |
473 | */ |
57356d63 |
474 | char *buf, dest[64]; |
8eebd221 |
475 | |
0e8f4cda |
476 | sk_getaddr(p->remote_addr, dest, 64); |
8eebd221 |
477 | |
57356d63 |
478 | buf = dupprintf("CONNECT %s:%i HTTP/1.1\r\nHost: %s:%i\r\n", |
479 | dest, p->remote_port, dest, p->remote_port); |
8eebd221 |
480 | sk_write(p->sub_socket, buf, strlen(buf)); |
57356d63 |
481 | sfree(buf); |
8eebd221 |
482 | |
1549e076 |
483 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
484 | char buf[sizeof(cfg.proxy_username)+sizeof(cfg.proxy_password)]; |
485 | char buf2[sizeof(buf)*4/3 + 100]; |
486 | int i, j, len; |
487 | sprintf(buf, "%s:%s", cfg.proxy_username, cfg.proxy_password); |
488 | len = strlen(buf); |
489 | sprintf(buf2, "Proxy-Authorization: basic "); |
490 | for (i = 0, j = strlen(buf2); i < len; i += 3, j += 4) |
491 | base64_encode_atom(buf+i, (len-i > 3 ? 3 : len-i), buf2+j); |
492 | strcpy(buf2+j, "\r\n"); |
493 | sk_write(p->sub_socket, buf2, strlen(buf2)); |
494 | } |
495 | |
9ddf18a4 |
496 | sk_write(p->sub_socket, "\r\n", 2); |
1549e076 |
497 | |
8eebd221 |
498 | p->state = 1; |
8eebd221 |
499 | return 0; |
500 | } |
501 | |
502 | if (change == PROXY_CHANGE_CLOSING) { |
503 | /* if our proxy negotiation process involves closing and opening |
504 | * new sockets, then we would want to intercept this closing |
505 | * callback when we were expecting it. if we aren't anticipating |
506 | * a socket close, then some error must have occurred. we'll |
507 | * just pass those errors up to the backend. |
508 | */ |
509 | return plug_closing(p->plug, p->closing_error_msg, |
510 | p->closing_error_code, |
511 | p->closing_calling_back); |
512 | } |
513 | |
514 | if (change == PROXY_CHANGE_SENT) { |
515 | /* some (or all) of what we wrote to the proxy was sent. |
516 | * we don't do anything new, however, until we receive the |
517 | * proxy's response. we might want to set a timer so we can |
518 | * timeout the proxy negotiation after a while... |
519 | */ |
520 | return 0; |
521 | } |
522 | |
523 | if (change == PROXY_CHANGE_ACCEPTING) { |
524 | /* we should _never_ see this, as we are using our socket to |
525 | * connect to a proxy, not accepting inbound connections. |
526 | * what should we do? close the socket with an appropriate |
527 | * error message? |
528 | */ |
529 | return plug_accepting(p->plug, p->accepting_sock); |
530 | } |
531 | |
532 | if (change == PROXY_CHANGE_RECEIVE) { |
533 | /* we have received data from the underlying socket, which |
534 | * we'll need to parse, process, and respond to appropriately. |
535 | */ |
536 | |
7983f47e |
537 | char *data, *datap; |
8eebd221 |
538 | int len; |
539 | int eol; |
540 | |
541 | if (p->state == 1) { |
542 | |
543 | int min_ver, maj_ver, status; |
544 | |
545 | /* get the status line */ |
7983f47e |
546 | len = bufchain_size(&p->pending_input_data); |
547 | assert(len > 0); /* or we wouldn't be here */ |
548 | data = smalloc(len); |
549 | bufchain_fetch(&p->pending_input_data, data, len); |
550 | |
8eebd221 |
551 | eol = get_line_end(data, len); |
7983f47e |
552 | if (eol < 0) { |
553 | sfree(data); |
554 | return 1; |
555 | } |
8eebd221 |
556 | |
7983f47e |
557 | status = -1; |
558 | /* We can't rely on whether the %n incremented the sscanf return */ |
559 | if (sscanf((char *)data, "HTTP/%i.%i %n", |
560 | &maj_ver, &min_ver, &status) < 2 || status == -1) { |
561 | plug_closing(p->plug, "Proxy error: HTTP response was absent", |
562 | PROXY_ERROR_GENERAL, 0); |
563 | sfree(data); |
564 | return 1; |
565 | } |
8eebd221 |
566 | |
567 | /* remove the status line from the input buffer. */ |
568 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
569 | if (data[status] != '2') { |
8eebd221 |
570 | /* error */ |
57356d63 |
571 | char *buf; |
7983f47e |
572 | data[eol] = '\0'; |
573 | while (eol > status && |
574 | (data[eol-1] == '\r' || data[eol-1] == '\n')) |
575 | data[--eol] = '\0'; |
57356d63 |
576 | buf = dupprintf("Proxy error: %s", data+status); |
7983f47e |
577 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
57356d63 |
578 | sfree(buf); |
7983f47e |
579 | sfree(data); |
8eebd221 |
580 | return 1; |
581 | } |
582 | |
7983f47e |
583 | sfree(data); |
584 | |
8eebd221 |
585 | p->state = 2; |
586 | } |
587 | |
588 | if (p->state == 2) { |
589 | |
590 | /* get headers. we're done when we get a |
591 | * header of length 2, (ie. just "\r\n") |
592 | */ |
593 | |
7983f47e |
594 | len = bufchain_size(&p->pending_input_data); |
595 | assert(len > 0); /* or we wouldn't be here */ |
596 | data = smalloc(len); |
597 | datap = data; |
598 | bufchain_fetch(&p->pending_input_data, data, len); |
599 | |
600 | eol = get_line_end(datap, len); |
601 | if (eol < 0) { |
602 | sfree(data); |
603 | return 1; |
604 | } |
8eebd221 |
605 | while (eol > 2) |
606 | { |
8eebd221 |
607 | bufchain_consume(&p->pending_input_data, eol); |
7983f47e |
608 | datap += eol; |
9ddf18a4 |
609 | len -= eol; |
7983f47e |
610 | eol = get_line_end(datap, len); |
8eebd221 |
611 | } |
612 | |
613 | if (eol == 2) { |
614 | /* we're done */ |
615 | bufchain_consume(&p->pending_input_data, 2); |
616 | proxy_activate(p); |
617 | /* proxy activate will have dealt with |
618 | * whatever is left of the buffer */ |
7983f47e |
619 | sfree(data); |
8eebd221 |
620 | return 1; |
621 | } |
622 | |
7983f47e |
623 | sfree(data); |
8eebd221 |
624 | return 1; |
625 | } |
626 | } |
627 | |
7983f47e |
628 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
8eebd221 |
629 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
630 | return 1; |
8eebd221 |
631 | } |
632 | |
633 | /* ---------------------------------------------------------------------- |
6971bbe7 |
634 | * SOCKS proxy type. |
8eebd221 |
635 | */ |
636 | |
6971bbe7 |
637 | /* SOCKS version 4 */ |
638 | int proxy_socks4_negotiate (Proxy_Socket p, int change) |
8eebd221 |
639 | { |
6971bbe7 |
640 | if (p->state == PROXY_CHANGE_NEW) { |
641 | |
642 | /* request format: |
643 | * version number (1 byte) = 4 |
644 | * command code (1 byte) |
645 | * 1 = CONNECT |
646 | * 2 = BIND |
647 | * dest. port (2 bytes) [network order] |
648 | * dest. address (4 bytes) |
649 | * user ID (variable length, null terminated string) |
650 | */ |
651 | |
652 | int length; |
653 | char * command; |
654 | |
68a49acb |
655 | if (sk_addrtype(p->remote_addr) != ADDRTYPE_IPV4) { |
7983f47e |
656 | plug_closing(p->plug, "Proxy error: SOCKS version 4 does" |
657 | " not support IPv6", PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
658 | return 1; |
659 | } |
660 | |
661 | length = strlen(cfg.proxy_username) + 9; |
de9aaffb |
662 | command = (char*) smalloc(length); |
6971bbe7 |
663 | strcpy(command + 8, cfg.proxy_username); |
664 | |
665 | command[0] = 4; /* version 4 */ |
666 | command[1] = 1; /* CONNECT command */ |
667 | |
668 | /* port */ |
669 | command[2] = (char) (p->remote_port >> 8) & 0xff; |
670 | command[3] = (char) p->remote_port & 0xff; |
671 | |
672 | /* address */ |
673 | sk_addrcopy(p->remote_addr, command + 4); |
674 | |
675 | sk_write(p->sub_socket, command, length); |
de9aaffb |
676 | sfree(command); |
6971bbe7 |
677 | |
678 | p->state = 1; |
679 | return 0; |
680 | } |
681 | |
682 | if (change == PROXY_CHANGE_CLOSING) { |
683 | /* if our proxy negotiation process involves closing and opening |
684 | * new sockets, then we would want to intercept this closing |
685 | * callback when we were expecting it. if we aren't anticipating |
686 | * a socket close, then some error must have occurred. we'll |
687 | * just pass those errors up to the backend. |
688 | */ |
689 | return plug_closing(p->plug, p->closing_error_msg, |
690 | p->closing_error_code, |
691 | p->closing_calling_back); |
692 | } |
693 | |
694 | if (change == PROXY_CHANGE_SENT) { |
695 | /* some (or all) of what we wrote to the proxy was sent. |
696 | * we don't do anything new, however, until we receive the |
697 | * proxy's response. we might want to set a timer so we can |
698 | * timeout the proxy negotiation after a while... |
699 | */ |
700 | return 0; |
701 | } |
702 | |
703 | if (change == PROXY_CHANGE_ACCEPTING) { |
704 | /* we should _never_ see this, as we are using our socket to |
705 | * connect to a proxy, not accepting inbound connections. |
706 | * what should we do? close the socket with an appropriate |
707 | * error message? |
708 | */ |
709 | return plug_accepting(p->plug, p->accepting_sock); |
710 | } |
711 | |
712 | if (change == PROXY_CHANGE_RECEIVE) { |
713 | /* we have received data from the underlying socket, which |
714 | * we'll need to parse, process, and respond to appropriately. |
715 | */ |
716 | |
717 | if (p->state == 1) { |
718 | /* response format: |
719 | * version number (1 byte) = 4 |
720 | * reply code (1 byte) |
721 | * 90 = request granted |
722 | * 91 = request rejected or failed |
723 | * 92 = request rejected due to lack of IDENTD on client |
724 | * 93 = request rejected due to difference in user ID |
725 | * (what we sent vs. what IDENTD said) |
726 | * dest. port (2 bytes) |
727 | * dest. address (4 bytes) |
728 | */ |
729 | |
7983f47e |
730 | char data[8]; |
6971bbe7 |
731 | |
7983f47e |
732 | if (bufchain_size(&p->pending_input_data) < 8) |
733 | return 1; /* not got anything yet */ |
734 | |
6971bbe7 |
735 | /* get the response */ |
7983f47e |
736 | bufchain_fetch(&p->pending_input_data, data, 8); |
6971bbe7 |
737 | |
738 | if (data[0] != 0) { |
7983f47e |
739 | plug_closing(p->plug, "Proxy error: SOCKS proxy responded with " |
6971bbe7 |
740 | "unexpected reply code version", |
741 | PROXY_ERROR_GENERAL, 0); |
742 | return 1; |
743 | } |
744 | |
745 | if (data[1] != 90) { |
746 | |
747 | switch (data[1]) { |
748 | case 92: |
7983f47e |
749 | plug_closing(p->plug, "Proxy error: SOCKS server wanted IDENTD on client", |
6971bbe7 |
750 | PROXY_ERROR_GENERAL, 0); |
751 | break; |
752 | case 93: |
7983f47e |
753 | plug_closing(p->plug, "Proxy error: Username and IDENTD on client don't agree", |
6971bbe7 |
754 | PROXY_ERROR_GENERAL, 0); |
755 | break; |
756 | case 91: |
757 | default: |
7983f47e |
758 | plug_closing(p->plug, "Proxy error: Error while communicating with proxy", |
6971bbe7 |
759 | PROXY_ERROR_GENERAL, 0); |
760 | break; |
761 | } |
762 | |
763 | return 1; |
764 | } |
7983f47e |
765 | bufchain_consume(&p->pending_input_data, 8); |
6971bbe7 |
766 | |
767 | /* we're done */ |
768 | proxy_activate(p); |
769 | /* proxy activate will have dealt with |
770 | * whatever is left of the buffer */ |
771 | return 1; |
772 | } |
773 | } |
774 | |
7983f47e |
775 | plug_closing(p->plug, "Proxy error: unexpected proxy error", |
6971bbe7 |
776 | PROXY_ERROR_UNEXPECTED, 0); |
777 | return 1; |
778 | } |
779 | |
780 | /* SOCKS version 5 */ |
781 | int proxy_socks5_negotiate (Proxy_Socket p, int change) |
782 | { |
783 | if (p->state == PROXY_CHANGE_NEW) { |
784 | |
785 | /* initial command: |
786 | * version number (1 byte) = 5 |
787 | * number of available authentication methods (1 byte) |
788 | * available authentication methods (1 byte * previous value) |
789 | * authentication methods: |
790 | * 0x00 = no authentication |
791 | * 0x01 = GSSAPI |
792 | * 0x02 = username/password |
793 | * 0x03 = CHAP |
794 | */ |
795 | |
aab91a3e |
796 | char command[4]; |
797 | int len; |
6971bbe7 |
798 | |
799 | command[0] = 5; /* version 5 */ |
aab91a3e |
800 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
801 | command[1] = 2; /* two methods supported: */ |
802 | command[2] = 0x00; /* no authentication */ |
803 | command[3] = 0x02; /* username/password */ |
804 | len = 4; |
805 | } else { |
806 | command[1] = 1; /* one methods supported: */ |
807 | command[2] = 0x00; /* no authentication */ |
808 | len = 3; |
809 | } |
6971bbe7 |
810 | |
aab91a3e |
811 | sk_write(p->sub_socket, command, len); |
6971bbe7 |
812 | |
813 | p->state = 1; |
814 | return 0; |
815 | } |
816 | |
817 | if (change == PROXY_CHANGE_CLOSING) { |
818 | /* if our proxy negotiation process involves closing and opening |
819 | * new sockets, then we would want to intercept this closing |
820 | * callback when we were expecting it. if we aren't anticipating |
821 | * a socket close, then some error must have occurred. we'll |
822 | * just pass those errors up to the backend. |
823 | */ |
824 | return plug_closing(p->plug, p->closing_error_msg, |
825 | p->closing_error_code, |
826 | p->closing_calling_back); |
827 | } |
828 | |
829 | if (change == PROXY_CHANGE_SENT) { |
830 | /* some (or all) of what we wrote to the proxy was sent. |
831 | * we don't do anything new, however, until we receive the |
832 | * proxy's response. we might want to set a timer so we can |
833 | * timeout the proxy negotiation after a while... |
834 | */ |
835 | return 0; |
836 | } |
837 | |
838 | if (change == PROXY_CHANGE_ACCEPTING) { |
839 | /* we should _never_ see this, as we are using our socket to |
840 | * connect to a proxy, not accepting inbound connections. |
841 | * what should we do? close the socket with an appropriate |
842 | * error message? |
843 | */ |
844 | return plug_accepting(p->plug, p->accepting_sock); |
845 | } |
846 | |
847 | if (change == PROXY_CHANGE_RECEIVE) { |
848 | /* we have received data from the underlying socket, which |
849 | * we'll need to parse, process, and respond to appropriately. |
850 | */ |
851 | |
6971bbe7 |
852 | if (p->state == 1) { |
853 | |
854 | /* initial response: |
855 | * version number (1 byte) = 5 |
856 | * authentication method (1 byte) |
857 | * authentication methods: |
858 | * 0x00 = no authentication |
859 | * 0x01 = GSSAPI |
860 | * 0x02 = username/password |
861 | * 0x03 = CHAP |
862 | * 0xff = no acceptable methods |
863 | */ |
7983f47e |
864 | char data[2]; |
865 | |
866 | if (bufchain_size(&p->pending_input_data) < 2) |
867 | return 1; /* not got anything yet */ |
6971bbe7 |
868 | |
869 | /* get the response */ |
7983f47e |
870 | bufchain_fetch(&p->pending_input_data, data, 2); |
6971bbe7 |
871 | |
872 | if (data[0] != 5) { |
7983f47e |
873 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned unexpected version", |
6971bbe7 |
874 | PROXY_ERROR_GENERAL, 0); |
875 | return 1; |
876 | } |
877 | |
878 | if (data[1] == 0x00) p->state = 2; /* no authentication needed */ |
879 | else if (data[1] == 0x01) p->state = 4; /* GSSAPI authentication */ |
880 | else if (data[1] == 0x02) p->state = 5; /* username/password authentication */ |
881 | else if (data[1] == 0x03) p->state = 6; /* CHAP authentication */ |
882 | else { |
7983f47e |
883 | plug_closing(p->plug, "Proxy error: SOCKS proxy did not accept our authentication", |
6971bbe7 |
884 | PROXY_ERROR_GENERAL, 0); |
885 | return 1; |
886 | } |
aab91a3e |
887 | bufchain_consume(&p->pending_input_data, 2); |
888 | } |
889 | |
890 | if (p->state == 7) { |
891 | |
892 | /* password authentication reply format: |
893 | * version number (1 bytes) = 1 |
894 | * reply code (1 byte) |
895 | * 0 = succeeded |
896 | * >0 = failed |
897 | */ |
7983f47e |
898 | char data[2]; |
899 | |
900 | if (bufchain_size(&p->pending_input_data) < 2) |
901 | return 1; /* not got anything yet */ |
aab91a3e |
902 | |
903 | /* get the response */ |
7983f47e |
904 | bufchain_fetch(&p->pending_input_data, data, 2); |
aab91a3e |
905 | |
906 | if (data[0] != 1) { |
7983f47e |
907 | plug_closing(p->plug, "Proxy error: SOCKS password " |
908 | "subnegotiation contained wrong version number", |
aab91a3e |
909 | PROXY_ERROR_GENERAL, 0); |
910 | return 1; |
911 | } |
912 | |
913 | if (data[1] != 0) { |
914 | |
7983f47e |
915 | plug_closing(p->plug, "Proxy error: SOCKS proxy refused" |
916 | " password authentication", |
aab91a3e |
917 | PROXY_ERROR_GENERAL, 0); |
918 | return 1; |
919 | } |
920 | |
921 | bufchain_consume(&p->pending_input_data, 2); |
922 | p->state = 2; /* now proceed as authenticated */ |
6971bbe7 |
923 | } |
924 | |
925 | if (p->state == 2) { |
926 | |
927 | /* request format: |
928 | * version number (1 byte) = 5 |
929 | * command code (1 byte) |
930 | * 1 = CONNECT |
931 | * 2 = BIND |
932 | * 3 = UDP ASSOCIATE |
933 | * reserved (1 byte) = 0x00 |
934 | * address type (1 byte) |
935 | * 1 = IPv4 |
936 | * 3 = domainname (first byte has length, no terminating null) |
937 | * 4 = IPv6 |
938 | * dest. address (variable) |
939 | * dest. port (2 bytes) [network order] |
940 | */ |
941 | |
942 | char command[22]; |
943 | int len; |
944 | |
f74d67ca |
945 | if (sk_addrtype(p->remote_addr) == ADDRTYPE_IPV4) { |
6971bbe7 |
946 | len = 10; |
947 | command[3] = 1; /* IPv4 */ |
948 | } else { |
949 | len = 22; |
950 | command[3] = 4; /* IPv6 */ |
951 | } |
952 | |
953 | command[0] = 5; /* version 5 */ |
954 | command[1] = 1; /* CONNECT command */ |
955 | command[2] = 0x00; |
956 | |
957 | /* address */ |
958 | sk_addrcopy(p->remote_addr, command+4); |
959 | |
960 | /* port */ |
961 | command[len-2] = (char) (p->remote_port >> 8) & 0xff; |
962 | command[len-1] = (char) p->remote_port & 0xff; |
963 | |
964 | sk_write(p->sub_socket, command, len); |
965 | |
966 | p->state = 3; |
967 | return 1; |
968 | } |
969 | |
970 | if (p->state == 3) { |
971 | |
972 | /* reply format: |
973 | * version number (1 bytes) = 5 |
974 | * reply code (1 byte) |
975 | * 0 = succeeded |
976 | * 1 = general SOCKS server failure |
977 | * 2 = connection not allowed by ruleset |
978 | * 3 = network unreachable |
979 | * 4 = host unreachable |
980 | * 5 = connection refused |
981 | * 6 = TTL expired |
982 | * 7 = command not supported |
983 | * 8 = address type not supported |
984 | * reserved (1 byte) = x00 |
985 | * address type (1 byte) |
986 | * 1 = IPv4 |
987 | * 3 = domainname (first byte has length, no terminating null) |
988 | * 4 = IPv6 |
989 | * server bound address (variable) |
990 | * server bound port (2 bytes) [network order] |
991 | */ |
7983f47e |
992 | char data[5]; |
993 | int len; |
994 | |
995 | /* First 5 bytes of packet are enough to tell its length. */ |
996 | if (bufchain_size(&p->pending_input_data) < 5) |
997 | return 1; /* not got anything yet */ |
6971bbe7 |
998 | |
999 | /* get the response */ |
7983f47e |
1000 | bufchain_fetch(&p->pending_input_data, data, 5); |
6971bbe7 |
1001 | |
1002 | if (data[0] != 5) { |
7983f47e |
1003 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned wrong version number", |
6971bbe7 |
1004 | PROXY_ERROR_GENERAL, 0); |
1005 | return 1; |
1006 | } |
1007 | |
1008 | if (data[1] != 0) { |
7983f47e |
1009 | char buf[256]; |
1010 | |
1011 | strcpy(buf, "Proxy error: "); |
6971bbe7 |
1012 | |
1013 | switch (data[1]) { |
7983f47e |
1014 | case 1: strcat(buf, "General SOCKS server failure"); break; |
1015 | case 2: strcat(buf, "Connection not allowed by ruleset"); break; |
1016 | case 3: strcat(buf, "Network unreachable"); break; |
1017 | case 4: strcat(buf, "Host unreachable"); break; |
1018 | case 5: strcat(buf, "Connection refused"); break; |
1019 | case 6: strcat(buf, "TTL expired"); break; |
1020 | case 7: strcat(buf, "Command not supported"); break; |
1021 | case 8: strcat(buf, "Address type not supported"); break; |
1022 | default: sprintf(buf+strlen(buf), |
1023 | "Unrecognised SOCKS error code %d", |
1024 | data[1]); |
6971bbe7 |
1025 | break; |
1026 | } |
7983f47e |
1027 | plug_closing(p->plug, buf, PROXY_ERROR_GENERAL, 0); |
1028 | |
1029 | return 1; |
1030 | } |
6971bbe7 |
1031 | |
7983f47e |
1032 | /* |
1033 | * Eat the rest of the reply packet. |
1034 | */ |
1035 | len = 6; /* first 4 bytes, last 2 */ |
1036 | switch (data[3]) { |
1037 | case 1: len += 4; break; /* IPv4 address */ |
1038 | case 4: len += 16; break;/* IPv6 address */ |
1039 | case 3: len += (unsigned char)data[4]; break; /* domain name */ |
1040 | default: |
1041 | plug_closing(p->plug, "Proxy error: SOCKS proxy returned " |
1042 | "unrecognised address format", |
1043 | PROXY_ERROR_GENERAL, 0); |
6971bbe7 |
1044 | return 1; |
1045 | } |
7983f47e |
1046 | if (bufchain_size(&p->pending_input_data) < len) |
1047 | return 1; /* not got whole reply yet */ |
1048 | bufchain_consume(&p->pending_input_data, len); |
6971bbe7 |
1049 | |
1050 | /* we're done */ |
1051 | proxy_activate(p); |
6971bbe7 |
1052 | return 1; |
1053 | } |
1054 | |
1055 | if (p->state == 4) { |
1056 | /* TODO: Handle GSSAPI authentication */ |
2192a8e4 |
1057 | plug_closing(p->plug, "Proxy error: We don't support GSSAPI authentication", |
6971bbe7 |
1058 | PROXY_ERROR_GENERAL, 0); |
1059 | return 1; |
1060 | } |
1061 | |
1062 | if (p->state == 5) { |
aab91a3e |
1063 | if (cfg.proxy_username[0] || cfg.proxy_password[0]) { |
1064 | char userpwbuf[514]; |
1065 | int ulen, plen; |
1066 | ulen = strlen(cfg.proxy_username); |
1067 | if (ulen > 255) ulen = 255; if (ulen < 1) ulen = 1; |
1068 | plen = strlen(cfg.proxy_password); |
1069 | if (plen > 255) plen = 255; if (plen < 1) plen = 1; |
1070 | userpwbuf[0] = 1; /* version number of subnegotiation */ |
1071 | userpwbuf[1] = ulen; |
1072 | memcpy(userpwbuf+2, cfg.proxy_username, ulen); |
1073 | userpwbuf[ulen+2] = plen; |
1074 | memcpy(userpwbuf+ulen+3, cfg.proxy_password, plen); |
1075 | sk_write(p->sub_socket, userpwbuf, ulen + plen + 3); |
1076 | p->state = 7; |
1077 | } else |
2192a8e4 |
1078 | plug_closing(p->plug, "Proxy error: Server chose " |
aab91a3e |
1079 | "username/password authentication but we " |
1080 | "didn't offer it!", |
6971bbe7 |
1081 | PROXY_ERROR_GENERAL, 0); |
1082 | return 1; |
1083 | } |
1084 | |
1085 | if (p->state == 6) { |
1086 | /* TODO: Handle CHAP authentication */ |
2192a8e4 |
1087 | plug_closing(p->plug, "Proxy error: We don't support CHAP authentication", |
6971bbe7 |
1088 | PROXY_ERROR_GENERAL, 0); |
1089 | return 1; |
1090 | } |
aab91a3e |
1091 | |
6971bbe7 |
1092 | } |
1093 | |
2192a8e4 |
1094 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
6971bbe7 |
1095 | PROXY_ERROR_UNEXPECTED, 0); |
1096 | return 1; |
8eebd221 |
1097 | } |
1098 | |
1099 | /* ---------------------------------------------------------------------- |
0e8f4cda |
1100 | * `Telnet' proxy type. |
8eebd221 |
1101 | * |
1102 | * (This is for ad-hoc proxies where you connect to the proxy's |
1103 | * telnet port and send a command such as `connect host port'. The |
1104 | * command is configurable, since this proxy type is typically not |
1105 | * standardised or at all well-defined.) |
1106 | */ |
1107 | |
1108 | int proxy_telnet_negotiate (Proxy_Socket p, int change) |
1109 | { |
0e8f4cda |
1110 | if (p->state == PROXY_CHANGE_NEW) { |
1111 | |
1112 | int so = 0, eo = 0; |
1113 | |
1114 | /* we need to escape \\, \%, \r, \n, \t, \x??, \0???, |
2d129d8e |
1115 | * %%, %host, %port, %user, and %pass |
0e8f4cda |
1116 | */ |
1117 | |
1118 | while (cfg.proxy_telnet_command[eo] != 0) { |
1119 | |
1120 | /* scan forward until we hit end-of-line, |
1121 | * or an escape character (\ or %) */ |
1122 | while (cfg.proxy_telnet_command[eo] != 0 && |
1123 | cfg.proxy_telnet_command[eo] != '%' && |
1124 | cfg.proxy_telnet_command[eo] != '\\') eo++; |
1125 | |
1126 | /* if we hit eol, break out of our escaping loop */ |
1127 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1128 | |
1129 | /* if there was any unescaped text before the escape |
1130 | * character, send that now */ |
1131 | if (eo != so) { |
1132 | sk_write(p->sub_socket, |
1133 | cfg.proxy_telnet_command + so, eo - so); |
1134 | } |
1135 | |
1136 | so = eo++; |
1137 | |
1138 | /* if the escape character was the last character of |
1139 | * the line, we'll just stop and send it. */ |
1140 | if (cfg.proxy_telnet_command[eo] == 0) break; |
1141 | |
1142 | if (cfg.proxy_telnet_command[so] == '\\') { |
1143 | |
1144 | /* we recognize \\, \%, \r, \n, \t, \x??. |
1145 | * anything else, we just send unescaped (including the \). |
1146 | */ |
1147 | |
1148 | switch (cfg.proxy_telnet_command[eo]) { |
1149 | |
1150 | case '\\': |
1151 | sk_write(p->sub_socket, "\\", 1); |
1152 | eo++; |
1153 | break; |
1154 | |
1155 | case '%': |
1156 | sk_write(p->sub_socket, "%%", 1); |
1157 | eo++; |
1158 | break; |
1159 | |
1160 | case 'r': |
1161 | sk_write(p->sub_socket, "\r", 1); |
1162 | eo++; |
1163 | break; |
1164 | |
1165 | case 'n': |
1166 | sk_write(p->sub_socket, "\n", 1); |
1167 | eo++; |
1168 | break; |
1169 | |
1170 | case 't': |
1171 | sk_write(p->sub_socket, "\t", 1); |
1172 | eo++; |
1173 | break; |
1174 | |
1175 | case 'x': |
1176 | case 'X': |
1177 | { |
1178 | /* escaped hexadecimal value (ie. \xff) */ |
1179 | unsigned char v = 0; |
1180 | int i = 0; |
1181 | |
1182 | for (;;) { |
1183 | eo++; |
1184 | if (cfg.proxy_telnet_command[eo] >= '0' && |
1185 | cfg.proxy_telnet_command[eo] <= '9') |
1186 | v += cfg.proxy_telnet_command[eo] - '0'; |
1187 | else if (cfg.proxy_telnet_command[eo] >= 'a' && |
1188 | cfg.proxy_telnet_command[eo] <= 'f') |
1189 | v += cfg.proxy_telnet_command[eo] - 'a' + 10; |
1190 | else if (cfg.proxy_telnet_command[eo] >= 'A' && |
1191 | cfg.proxy_telnet_command[eo] <= 'F') |
1192 | v += cfg.proxy_telnet_command[eo] - 'A' + 10; |
1193 | else { |
1194 | /* non hex character, so we abort and just |
1195 | * send the whole thing unescaped (including \x) |
1196 | */ |
1197 | sk_write(p->sub_socket, "\\", 1); |
1198 | eo = so + 1; |
1199 | break; |
1200 | } |
1201 | |
1202 | /* we only extract two hex characters */ |
1203 | if (i == 1) { |
1204 | sk_write(p->sub_socket, &v, 1); |
1205 | eo++; |
1206 | break; |
1207 | } |
1208 | |
1209 | i++; |
1210 | v <<= 4; |
1211 | } |
1212 | } |
1213 | break; |
1214 | |
1215 | default: |
1216 | sk_write(p->sub_socket, |
1217 | cfg.proxy_telnet_command + so, 2); |
1218 | eo++; |
1219 | break; |
1220 | } |
1221 | } else { |
1222 | |
2d129d8e |
1223 | /* % escape. we recognize %%, %host, %port, %user, %pass. |
1224 | * anything else, we just send unescaped (including the %). |
1225 | */ |
0e8f4cda |
1226 | |
1227 | if (cfg.proxy_telnet_command[eo] == '%') { |
1228 | sk_write(p->sub_socket, "%", 1); |
1229 | eo++; |
2d129d8e |
1230 | } |
0e8f4cda |
1231 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1232 | "host", 4) == 0) { |
1233 | char dest[64]; |
1234 | sk_getaddr(p->remote_addr, dest, 64); |
1235 | sk_write(p->sub_socket, dest, strlen(dest)); |
1236 | eo += 4; |
2d129d8e |
1237 | } |
0e8f4cda |
1238 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1239 | "port", 4) == 0) { |
1240 | char port[8]; |
1241 | sprintf(port, "%i", p->remote_port); |
1242 | sk_write(p->sub_socket, port, strlen(port)); |
1243 | eo += 4; |
2d129d8e |
1244 | } |
1245 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1246 | "user", 4) == 0) { |
1247 | sk_write(p->sub_socket, cfg.proxy_username, |
1248 | strlen(cfg.proxy_username)); |
1249 | eo += 4; |
1250 | } |
1251 | else if (strnicmp(cfg.proxy_telnet_command + eo, |
1252 | "pass", 4) == 0) { |
1253 | sk_write(p->sub_socket, cfg.proxy_password, |
1254 | strlen(cfg.proxy_password)); |
1255 | eo += 4; |
1256 | } |
0e8f4cda |
1257 | else { |
1258 | /* we don't escape this, so send the % now, and |
1259 | * don't advance eo, so that we'll consider the |
1260 | * text immediately following the % as unescaped. |
1261 | */ |
1262 | sk_write(p->sub_socket, "%", 1); |
1263 | } |
1264 | } |
1265 | |
1266 | /* resume scanning for additional escapes after this one. */ |
1267 | so = eo; |
1268 | } |
1269 | |
1270 | /* if there is any unescaped text at the end of the line, send it */ |
1271 | if (eo != so) { |
1272 | sk_write(p->sub_socket, cfg.proxy_telnet_command + so, eo - so); |
1273 | } |
1274 | |
1275 | p->state = 1; |
0e8f4cda |
1276 | return 0; |
1277 | } |
1278 | |
1279 | if (change == PROXY_CHANGE_CLOSING) { |
1280 | /* if our proxy negotiation process involves closing and opening |
1281 | * new sockets, then we would want to intercept this closing |
1282 | * callback when we were expecting it. if we aren't anticipating |
1283 | * a socket close, then some error must have occurred. we'll |
1284 | * just pass those errors up to the backend. |
1285 | */ |
1286 | return plug_closing(p->plug, p->closing_error_msg, |
1287 | p->closing_error_code, |
1288 | p->closing_calling_back); |
1289 | } |
1290 | |
1291 | if (change == PROXY_CHANGE_SENT) { |
1292 | /* some (or all) of what we wrote to the proxy was sent. |
1293 | * we don't do anything new, however, until we receive the |
1294 | * proxy's response. we might want to set a timer so we can |
1295 | * timeout the proxy negotiation after a while... |
1296 | */ |
1297 | return 0; |
1298 | } |
1299 | |
1300 | if (change == PROXY_CHANGE_ACCEPTING) { |
1301 | /* we should _never_ see this, as we are using our socket to |
1302 | * connect to a proxy, not accepting inbound connections. |
1303 | * what should we do? close the socket with an appropriate |
1304 | * error message? |
1305 | */ |
1306 | return plug_accepting(p->plug, p->accepting_sock); |
1307 | } |
1308 | |
1309 | if (change == PROXY_CHANGE_RECEIVE) { |
1310 | /* we have received data from the underlying socket, which |
1311 | * we'll need to parse, process, and respond to appropriately. |
1312 | */ |
1313 | |
1314 | /* we're done */ |
1315 | proxy_activate(p); |
1316 | /* proxy activate will have dealt with |
1317 | * whatever is left of the buffer */ |
1318 | return 1; |
1319 | } |
1320 | |
2192a8e4 |
1321 | plug_closing(p->plug, "Proxy error: Unexpected proxy error", |
0e8f4cda |
1322 | PROXY_ERROR_UNEXPECTED, 0); |
6971bbe7 |
1323 | return 1; |
8eebd221 |
1324 | } |