c5e438ec |
1 | /* |
2 | * Unix networking abstraction. |
3 | */ |
4 | |
5 | #include <stdio.h> |
6 | #include <stdlib.h> |
7 | #include <assert.h> |
8 | #include <errno.h> |
9 | #include <fcntl.h> |
10 | #include <unistd.h> |
11 | #include <sys/types.h> |
12 | #include <sys/socket.h> |
13 | #include <sys/ioctl.h> |
14 | #include <arpa/inet.h> |
15 | #include <netinet/in.h> |
16 | #include <netinet/tcp.h> |
17 | #include <netdb.h> |
18 | |
19 | #define DEFINE_PLUG_METHOD_MACROS |
20 | #include "putty.h" |
21 | #include "network.h" |
22 | #include "tree234.h" |
23 | |
24 | struct Socket_tag { |
25 | struct socket_function_table *fn; |
26 | /* the above variable absolutely *must* be the first in this structure */ |
27 | char *error; |
28 | int s; |
29 | Plug plug; |
30 | void *private_ptr; |
31 | bufchain output_data; |
32 | int connected; |
33 | int writable; |
34 | int frozen; /* this causes readability notifications to be ignored */ |
35 | int frozen_readable; /* this means we missed at least one readability |
36 | * notification while we were frozen */ |
37 | int localhost_only; /* for listening sockets */ |
38 | char oobdata[1]; |
39 | int sending_oob; |
40 | int oobpending; /* is there OOB data available to read? */ |
41 | int oobinline; |
42 | int pending_error; /* in case send() returns error */ |
43 | int listener; |
44 | }; |
45 | |
46 | /* |
47 | * We used to typedef struct Socket_tag *Socket. |
48 | * |
49 | * Since we have made the networking abstraction slightly more |
50 | * abstract, Socket no longer means a tcp socket (it could mean |
51 | * an ssl socket). So now we must use Actual_Socket when we know |
52 | * we are talking about a tcp socket. |
53 | */ |
54 | typedef struct Socket_tag *Actual_Socket; |
55 | |
56 | struct SockAddr_tag { |
57 | char *error; |
58 | /* address family this belongs to, AF_INET for IPv4, AF_INET6 for IPv6. */ |
59 | int family; |
60 | unsigned long address; /* Address IPv4 style. */ |
61 | #ifdef IPV6 |
62 | struct addrinfo *ai; /* Address IPv6 style. */ |
63 | #endif |
64 | }; |
65 | |
66 | static tree234 *sktree; |
67 | |
68 | static int cmpfortree(void *av, void *bv) |
69 | { |
70 | Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv; |
71 | int as = a->s, bs = b->s; |
72 | if (as < bs) |
73 | return -1; |
74 | if (as > bs) |
75 | return +1; |
76 | return 0; |
77 | } |
78 | |
79 | static int cmpforsearch(void *av, void *bv) |
80 | { |
81 | Actual_Socket b = (Actual_Socket) bv; |
82 | int as = (int) av, bs = b->s; |
83 | if (as < bs) |
84 | return -1; |
85 | if (as > bs) |
86 | return +1; |
87 | return 0; |
88 | } |
89 | |
90 | void sk_init(void) |
91 | { |
92 | sktree = newtree234(cmpfortree); |
93 | } |
94 | |
95 | void sk_cleanup(void) |
96 | { |
97 | Actual_Socket s; |
98 | int i; |
99 | |
100 | if (sktree) { |
101 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
102 | close(s->s); |
103 | } |
104 | } |
105 | } |
106 | |
107 | char *error_string(int error) |
108 | { |
e266735f |
109 | return strerror(error); |
c5e438ec |
110 | } |
111 | |
112 | SockAddr sk_namelookup(char *host, char **canonicalname) |
113 | { |
114 | SockAddr ret = smalloc(sizeof(struct SockAddr_tag)); |
115 | unsigned long a; |
116 | struct hostent *h = NULL; |
117 | char realhost[8192]; |
118 | |
119 | /* Clear the structure and default to IPv4. */ |
120 | memset(ret, 0, sizeof(struct SockAddr_tag)); |
121 | ret->family = 0; /* We set this one when we have resolved the host. */ |
122 | *realhost = '\0'; |
123 | ret->error = NULL; |
124 | |
125 | if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
126 | #ifdef IPV6 |
127 | if (getaddrinfo(host, NULL, NULL, &ret->ai) == 0) { |
128 | ret->family = ret->ai->ai_family; |
129 | } else |
130 | #endif |
131 | { |
132 | /* |
133 | * Otherwise use the IPv4-only gethostbyname... (NOTE: |
134 | * we don't use gethostbyname as a fallback!) |
135 | */ |
136 | if (ret->family == 0) { |
137 | /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */ |
138 | if ( (h = gethostbyname(host)) ) |
139 | ret->family = AF_INET; |
140 | } |
8c43874c |
141 | if (ret->family == 0) { |
c5e438ec |
142 | ret->error = (h_errno == HOST_NOT_FOUND || |
143 | h_errno == NO_DATA || |
144 | h_errno == NO_ADDRESS ? "Host does not exist" : |
145 | h_errno == TRY_AGAIN ? |
146 | "Temporary name service failure" : |
147 | "gethostbyname: unknown error"); |
8c43874c |
148 | return ret; |
149 | } |
c5e438ec |
150 | } |
151 | |
152 | #ifdef IPV6 |
153 | /* If we got an address info use that... */ |
154 | if (ret->ai) { |
155 | |
156 | /* Are we in IPv4 fallback mode? */ |
157 | /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */ |
158 | if (ret->family == AF_INET) |
159 | memcpy(&a, |
160 | (char *) &((struct sockaddr_in *) ret->ai-> |
161 | ai_addr)->sin_addr, sizeof(a)); |
162 | |
163 | /* Now let's find that canonicalname... */ |
164 | if (getnameinfo((struct sockaddr *) ret->ai->ai_addr, |
165 | ret->family == |
166 | AF_INET ? sizeof(struct sockaddr_in) : |
167 | sizeof(struct sockaddr_in6), realhost, |
168 | sizeof(realhost), NULL, 0, 0) != 0) { |
169 | strncpy(realhost, host, sizeof(realhost)); |
170 | } |
171 | } |
172 | /* We used the IPv4-only gethostbyname()... */ |
173 | else |
174 | #endif |
175 | { |
176 | memcpy(&a, h->h_addr, sizeof(a)); |
177 | /* This way we are always sure the h->h_name is valid :) */ |
178 | strncpy(realhost, h->h_name, sizeof(realhost)); |
179 | } |
180 | } else { |
181 | /* |
182 | * This must be a numeric IPv4 address because it caused a |
183 | * success return from inet_addr. |
184 | */ |
185 | ret->family = AF_INET; |
186 | strncpy(realhost, host, sizeof(realhost)); |
187 | } |
188 | ret->address = ntohl(a); |
189 | realhost[lenof(realhost)-1] = '\0'; |
190 | *canonicalname = smalloc(1+strlen(realhost)); |
191 | strcpy(*canonicalname, realhost); |
192 | return ret; |
193 | } |
194 | |
195 | void sk_getaddr(SockAddr addr, char *buf, int buflen) |
196 | { |
197 | #ifdef IPV6 |
198 | if (addr->family == AF_INET) { |
199 | #endif |
200 | struct in_addr a; |
201 | a.s_addr = htonl(addr->address); |
202 | strncpy(buf, inet_ntoa(a), buflen); |
203 | #ifdef IPV6 |
204 | } else { |
205 | FIXME; /* I don't know how to get a text form of an IPv6 address. */ |
206 | } |
207 | #endif |
208 | } |
209 | |
210 | int sk_addrtype(SockAddr addr) |
211 | { |
212 | return (addr->family == AF_INET ? ADDRTYPE_IPV4 : ADDRTYPE_IPV6); |
213 | } |
214 | |
215 | void sk_addrcopy(SockAddr addr, char *buf) |
216 | { |
217 | #ifdef IPV6 |
218 | if (addr->family == AF_INET) { |
219 | #endif |
220 | struct in_addr a; |
221 | a.s_addr = htonl(addr->address); |
222 | memcpy(buf, (char*) &a.s_addr, 4); |
223 | #ifdef IPV6 |
224 | } else { |
225 | memcpy(buf, (char*) addr->ai, 16); |
226 | } |
227 | #endif |
228 | } |
229 | |
230 | void sk_addr_free(SockAddr addr) |
231 | { |
232 | sfree(addr); |
233 | } |
234 | |
235 | static Plug sk_tcp_plug(Socket sock, Plug p) |
236 | { |
237 | Actual_Socket s = (Actual_Socket) sock; |
238 | Plug ret = s->plug; |
239 | if (p) |
240 | s->plug = p; |
241 | return ret; |
242 | } |
243 | |
244 | static void sk_tcp_flush(Socket s) |
245 | { |
246 | /* |
247 | * We send data to the socket as soon as we can anyway, |
248 | * so we don't need to do anything here. :-) |
249 | */ |
250 | } |
251 | |
252 | static void sk_tcp_close(Socket s); |
253 | static int sk_tcp_write(Socket s, char *data, int len); |
254 | static int sk_tcp_write_oob(Socket s, char *data, int len); |
255 | static void sk_tcp_set_private_ptr(Socket s, void *ptr); |
256 | static void *sk_tcp_get_private_ptr(Socket s); |
257 | static void sk_tcp_set_frozen(Socket s, int is_frozen); |
258 | static char *sk_tcp_socket_error(Socket s); |
259 | |
260 | Socket sk_register(void *sock, Plug plug) |
261 | { |
262 | static struct socket_function_table fn_table = { |
263 | sk_tcp_plug, |
264 | sk_tcp_close, |
265 | sk_tcp_write, |
266 | sk_tcp_write_oob, |
267 | sk_tcp_flush, |
268 | sk_tcp_set_private_ptr, |
269 | sk_tcp_get_private_ptr, |
270 | sk_tcp_set_frozen, |
271 | sk_tcp_socket_error |
272 | }; |
273 | |
274 | Actual_Socket ret; |
275 | |
276 | /* |
277 | * Create Socket structure. |
278 | */ |
279 | ret = smalloc(sizeof(struct Socket_tag)); |
280 | ret->fn = &fn_table; |
281 | ret->error = NULL; |
282 | ret->plug = plug; |
283 | bufchain_init(&ret->output_data); |
284 | ret->writable = 1; /* to start with */ |
285 | ret->sending_oob = 0; |
286 | ret->frozen = 1; |
287 | ret->frozen_readable = 0; |
288 | ret->localhost_only = 0; /* unused, but best init anyway */ |
289 | ret->pending_error = 0; |
290 | ret->oobpending = FALSE; |
291 | ret->listener = 0; |
292 | |
293 | ret->s = (int)sock; |
294 | |
295 | if (ret->s < 0) { |
296 | ret->error = error_string(errno); |
297 | return (Socket) ret; |
298 | } |
299 | |
300 | ret->oobinline = 0; |
301 | |
302 | add234(sktree, ret); |
303 | |
304 | return (Socket) ret; |
305 | } |
306 | |
307 | Socket sk_new(SockAddr addr, int port, int privport, int oobinline, |
308 | int nodelay, Plug plug) |
309 | { |
310 | static struct socket_function_table fn_table = { |
311 | sk_tcp_plug, |
312 | sk_tcp_close, |
313 | sk_tcp_write, |
314 | sk_tcp_write_oob, |
315 | sk_tcp_flush, |
316 | sk_tcp_set_private_ptr, |
317 | sk_tcp_get_private_ptr, |
318 | sk_tcp_set_frozen, |
319 | sk_tcp_socket_error |
320 | }; |
321 | |
322 | int s; |
323 | #ifdef IPV6 |
324 | struct sockaddr_in6 a6; |
325 | #endif |
326 | struct sockaddr_in a; |
327 | int err; |
328 | Actual_Socket ret; |
329 | short localport; |
330 | |
331 | /* |
332 | * Create Socket structure. |
333 | */ |
334 | ret = smalloc(sizeof(struct Socket_tag)); |
335 | ret->fn = &fn_table; |
336 | ret->error = NULL; |
337 | ret->plug = plug; |
338 | bufchain_init(&ret->output_data); |
339 | ret->connected = 0; /* to start with */ |
340 | ret->writable = 0; /* to start with */ |
341 | ret->sending_oob = 0; |
342 | ret->frozen = 0; |
343 | ret->frozen_readable = 0; |
344 | ret->localhost_only = 0; /* unused, but best init anyway */ |
345 | ret->pending_error = 0; |
346 | ret->oobpending = FALSE; |
347 | ret->listener = 0; |
348 | |
349 | /* |
350 | * Open socket. |
351 | */ |
352 | s = socket(addr->family, SOCK_STREAM, 0); |
353 | ret->s = s; |
354 | |
355 | if (s < 0) { |
356 | ret->error = error_string(errno); |
357 | return (Socket) ret; |
358 | } |
359 | |
360 | ret->oobinline = oobinline; |
361 | if (oobinline) { |
362 | int b = TRUE; |
363 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b)); |
364 | } |
365 | |
366 | if (nodelay) { |
367 | int b = TRUE; |
368 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b)); |
369 | } |
370 | |
371 | /* |
372 | * Bind to local address. |
373 | */ |
374 | if (privport) |
375 | localport = 1023; /* count from 1023 downwards */ |
376 | else |
377 | localport = 0; /* just use port 0 (ie kernel picks) */ |
378 | |
379 | /* Loop round trying to bind */ |
380 | while (1) { |
381 | int retcode; |
382 | |
383 | #ifdef IPV6 |
384 | if (addr->family == AF_INET6) { |
385 | memset(&a6, 0, sizeof(a6)); |
386 | a6.sin6_family = AF_INET6; |
387 | /*a6.sin6_addr = in6addr_any; *//* == 0 */ |
388 | a6.sin6_port = htons(localport); |
389 | } else |
390 | #endif |
391 | { |
392 | a.sin_family = AF_INET; |
393 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
394 | a.sin_port = htons(localport); |
395 | } |
396 | #ifdef IPV6 |
397 | retcode = bind(s, (addr->family == AF_INET6 ? |
398 | (struct sockaddr *) &a6 : |
399 | (struct sockaddr *) &a), |
400 | (addr->family == |
401 | AF_INET6 ? sizeof(a6) : sizeof(a))); |
402 | #else |
403 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
404 | #endif |
405 | if (retcode >= 0) { |
406 | err = 0; |
407 | break; /* done */ |
408 | } else { |
409 | err = errno; |
410 | if (err != EADDRINUSE) /* failed, for a bad reason */ |
411 | break; |
412 | } |
413 | |
414 | if (localport == 0) |
415 | break; /* we're only looping once */ |
416 | localport--; |
417 | if (localport == 0) |
418 | break; /* we might have got to the end */ |
419 | } |
420 | |
421 | if (err) { |
422 | ret->error = error_string(err); |
423 | return (Socket) ret; |
424 | } |
425 | |
426 | /* |
427 | * Connect to remote address. |
428 | */ |
429 | #ifdef IPV6 |
430 | if (addr->family == AF_INET6) { |
431 | memset(&a, 0, sizeof(a)); |
432 | a6.sin6_family = AF_INET6; |
433 | a6.sin6_port = htons((short) port); |
434 | a6.sin6_addr = |
435 | ((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr; |
436 | } else |
437 | #endif |
438 | { |
439 | a.sin_family = AF_INET; |
440 | a.sin_addr.s_addr = htonl(addr->address); |
441 | a.sin_port = htons((short) port); |
442 | } |
443 | |
444 | if (( |
445 | #ifdef IPV6 |
446 | connect(s, ((addr->family == AF_INET6) ? |
447 | (struct sockaddr *) &a6 : (struct sockaddr *) &a), |
448 | (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a)) |
449 | #else |
450 | connect(s, (struct sockaddr *) &a, sizeof(a)) |
451 | #endif |
452 | ) < 0) { |
453 | /* |
454 | * FIXME: We are prepared to receive EWOULDBLOCK here, |
455 | * because we might want the connection to be made |
456 | * asynchronously; but how do we actually arrange this in |
457 | * Unix? I forget. |
458 | */ |
459 | if ( errno != EWOULDBLOCK ) { |
460 | ret->error = error_string(errno); |
461 | return (Socket) ret; |
462 | } |
463 | } else { |
464 | /* |
465 | * If we _don't_ get EWOULDBLOCK, the connect has completed |
466 | * and we should set the socket as connected and writable. |
467 | */ |
468 | ret->connected = 1; |
469 | ret->writable = 1; |
470 | } |
471 | |
472 | add234(sktree, ret); |
473 | |
474 | return (Socket) ret; |
475 | } |
476 | |
477 | Socket sk_newlistener(int port, Plug plug, int local_host_only) |
478 | { |
479 | static struct socket_function_table fn_table = { |
480 | sk_tcp_plug, |
481 | sk_tcp_close, |
482 | sk_tcp_write, |
483 | sk_tcp_write_oob, |
484 | sk_tcp_flush, |
485 | sk_tcp_set_private_ptr, |
486 | sk_tcp_get_private_ptr, |
487 | sk_tcp_set_frozen, |
488 | sk_tcp_socket_error |
489 | }; |
490 | |
491 | int s; |
492 | #ifdef IPV6 |
493 | struct sockaddr_in6 a6; |
494 | #endif |
495 | struct sockaddr_in a; |
496 | int err; |
497 | Actual_Socket ret; |
498 | int retcode; |
499 | int on = 1; |
500 | |
501 | /* |
502 | * Create Socket structure. |
503 | */ |
504 | ret = smalloc(sizeof(struct Socket_tag)); |
505 | ret->fn = &fn_table; |
506 | ret->error = NULL; |
507 | ret->plug = plug; |
508 | bufchain_init(&ret->output_data); |
509 | ret->writable = 0; /* to start with */ |
510 | ret->sending_oob = 0; |
511 | ret->frozen = 0; |
512 | ret->frozen_readable = 0; |
513 | ret->localhost_only = local_host_only; |
514 | ret->pending_error = 0; |
515 | ret->oobpending = FALSE; |
516 | ret->listener = 1; |
517 | |
518 | /* |
519 | * Open socket. |
520 | */ |
521 | s = socket(AF_INET, SOCK_STREAM, 0); |
522 | ret->s = s; |
523 | |
524 | if (s < 0) { |
525 | ret->error = error_string(errno); |
526 | return (Socket) ret; |
527 | } |
528 | |
529 | ret->oobinline = 0; |
530 | |
531 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on)); |
532 | |
533 | #ifdef IPV6 |
534 | if (addr->family == AF_INET6) { |
535 | memset(&a6, 0, sizeof(a6)); |
536 | a6.sin6_family = AF_INET6; |
537 | if (local_host_only) |
538 | a6.sin6_addr = in6addr_loopback; |
539 | else |
540 | a6.sin6_addr = in6addr_any; |
541 | a6.sin6_port = htons(port); |
542 | } else |
543 | #endif |
544 | { |
545 | a.sin_family = AF_INET; |
546 | if (local_host_only) |
547 | a.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
548 | else |
549 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
550 | a.sin_port = htons((short)port); |
551 | } |
552 | #ifdef IPV6 |
553 | retcode = bind(s, (addr->family == AF_INET6 ? |
554 | (struct sockaddr *) &a6 : |
555 | (struct sockaddr *) &a), |
556 | (addr->family == |
557 | AF_INET6 ? sizeof(a6) : sizeof(a))); |
558 | #else |
559 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
560 | #endif |
561 | if (retcode >= 0) { |
562 | err = 0; |
563 | } else { |
564 | err = errno; |
565 | } |
566 | |
567 | if (err) { |
568 | ret->error = error_string(err); |
569 | return (Socket) ret; |
570 | } |
571 | |
572 | |
573 | if (listen(s, SOMAXCONN) < 0) { |
574 | close(s); |
575 | ret->error = error_string(errno); |
576 | return (Socket) ret; |
577 | } |
578 | |
579 | add234(sktree, ret); |
580 | |
581 | return (Socket) ret; |
582 | } |
583 | |
584 | static void sk_tcp_close(Socket sock) |
585 | { |
586 | Actual_Socket s = (Actual_Socket) sock; |
587 | |
588 | del234(sktree, s); |
589 | close(s->s); |
590 | sfree(s); |
591 | } |
592 | |
593 | /* |
594 | * The function which tries to send on a socket once it's deemed |
595 | * writable. |
596 | */ |
597 | void try_send(Actual_Socket s) |
598 | { |
599 | while (s->sending_oob || bufchain_size(&s->output_data) > 0) { |
600 | int nsent; |
601 | int err; |
602 | void *data; |
603 | int len, urgentflag; |
604 | |
605 | if (s->sending_oob) { |
606 | urgentflag = MSG_OOB; |
607 | len = s->sending_oob; |
608 | data = &s->oobdata; |
609 | } else { |
610 | urgentflag = 0; |
611 | bufchain_prefix(&s->output_data, &data, &len); |
612 | } |
613 | nsent = send(s->s, data, len, urgentflag); |
614 | noise_ultralight(nsent); |
615 | if (nsent <= 0) { |
616 | err = (nsent < 0 ? errno : 0); |
617 | if (err == EWOULDBLOCK) { |
618 | /* |
619 | * Perfectly normal: we've sent all we can for the moment. |
620 | */ |
621 | s->writable = FALSE; |
622 | return; |
623 | } else if (nsent == 0 || |
624 | err == ECONNABORTED || err == ECONNRESET) { |
625 | /* |
626 | * If send() returns CONNABORTED or CONNRESET, we |
627 | * unfortunately can't just call plug_closing(), |
628 | * because it's quite likely that we're currently |
629 | * _in_ a call from the code we'd be calling back |
630 | * to, so we'd have to make half the SSH code |
631 | * reentrant. Instead we flag a pending error on |
632 | * the socket, to be dealt with (by calling |
633 | * plug_closing()) at some suitable future moment. |
634 | */ |
635 | s->pending_error = err; |
636 | return; |
637 | } else { |
638 | /* We're inside the Unix frontend here, so we know |
639 | * that the frontend handle is unnecessary. */ |
640 | logevent(NULL, error_string(err)); |
641 | fatalbox("%s", error_string(err)); |
642 | } |
643 | } else { |
644 | if (s->sending_oob) { |
645 | if (nsent < len) { |
646 | memmove(s->oobdata, s->oobdata+nsent, len-nsent); |
647 | s->sending_oob = len - nsent; |
648 | } else { |
649 | s->sending_oob = 0; |
650 | } |
651 | } else { |
652 | bufchain_consume(&s->output_data, nsent); |
653 | } |
654 | } |
655 | } |
656 | } |
657 | |
658 | static int sk_tcp_write(Socket sock, char *buf, int len) |
659 | { |
660 | Actual_Socket s = (Actual_Socket) sock; |
661 | |
662 | /* |
663 | * Add the data to the buffer list on the socket. |
664 | */ |
665 | bufchain_add(&s->output_data, buf, len); |
666 | |
667 | /* |
668 | * Now try sending from the start of the buffer list. |
669 | */ |
670 | if (s->writable) |
671 | try_send(s); |
672 | |
673 | return bufchain_size(&s->output_data); |
674 | } |
675 | |
676 | static int sk_tcp_write_oob(Socket sock, char *buf, int len) |
677 | { |
678 | Actual_Socket s = (Actual_Socket) sock; |
679 | |
680 | /* |
681 | * Replace the buffer list on the socket with the data. |
682 | */ |
683 | bufchain_clear(&s->output_data); |
684 | assert(len <= sizeof(s->oobdata)); |
685 | memcpy(s->oobdata, buf, len); |
686 | s->sending_oob = len; |
687 | |
688 | /* |
689 | * Now try sending from the start of the buffer list. |
690 | */ |
691 | if (s->writable) |
692 | try_send(s); |
693 | |
694 | return s->sending_oob; |
695 | } |
696 | |
697 | int select_result(int fd, int event) |
698 | { |
699 | int ret; |
700 | int err; |
701 | char buf[20480]; /* nice big buffer for plenty of speed */ |
702 | Actual_Socket s; |
703 | u_long atmark; |
704 | |
705 | /* Find the Socket structure */ |
706 | s = find234(sktree, (void *) fd, cmpforsearch); |
707 | if (!s) |
708 | return 1; /* boggle */ |
709 | |
710 | noise_ultralight(event); |
711 | |
712 | switch (event) { |
713 | #ifdef FIXME_NONBLOCKING_CONNECTIONS |
714 | case FIXME: /* connected */ |
715 | s->connected = s->writable = 1; |
716 | break; |
717 | #endif |
718 | case 4: /* exceptional */ |
719 | if (!s->oobinline) { |
720 | /* |
721 | * On a non-oobinline socket, this indicates that we |
722 | * can immediately perform an OOB read and get back OOB |
723 | * data, which we will send to the back end with |
724 | * type==2 (urgent data). |
725 | */ |
726 | ret = recv(s->s, buf, sizeof(buf), MSG_OOB); |
727 | noise_ultralight(ret); |
728 | if (ret <= 0) { |
729 | char *str = (ret == 0 ? "Internal networking trouble" : |
730 | error_string(errno)); |
731 | /* We're inside the Unix frontend here, so we know |
732 | * that the frontend handle is unnecessary. */ |
733 | logevent(NULL, str); |
734 | fatalbox("%s", str); |
735 | } else { |
736 | return plug_receive(s->plug, 2, buf, ret); |
737 | } |
738 | break; |
739 | } |
740 | |
741 | /* |
742 | * If we reach here, this is an oobinline socket, which |
56e5b2db |
743 | * means we should set s->oobpending and then deal with it |
744 | * when we get called for the readability event (which |
745 | * should also occur). |
c5e438ec |
746 | */ |
747 | s->oobpending = TRUE; |
56e5b2db |
748 | break; |
c5e438ec |
749 | case 1: /* readable; also acceptance */ |
750 | if (s->listener) { |
751 | /* |
752 | * On a listening socket, the readability event means a |
753 | * connection is ready to be accepted. |
754 | */ |
755 | struct sockaddr_in isa; |
756 | int addrlen = sizeof(struct sockaddr_in); |
757 | int t; /* socket of connection */ |
758 | |
759 | memset(&isa, 0, sizeof(struct sockaddr_in)); |
760 | err = 0; |
761 | t = accept(s->s,(struct sockaddr *)&isa,&addrlen); |
762 | if (t < 0) { |
763 | break; |
764 | } |
765 | |
766 | if (s->localhost_only && |
767 | ntohl(isa.sin_addr.s_addr) != INADDR_LOOPBACK) { |
768 | close(t); /* someone let nonlocal through?! */ |
769 | } else if (plug_accepting(s->plug, (void*)t)) { |
770 | close(t); /* denied or error */ |
771 | } |
772 | break; |
773 | } |
774 | |
775 | /* |
776 | * If we reach here, this is not a listening socket, so |
777 | * readability really means readability. |
778 | */ |
779 | |
780 | /* In the case the socket is still frozen, we don't even bother */ |
781 | if (s->frozen) { |
782 | s->frozen_readable = 1; |
783 | break; |
784 | } |
785 | |
786 | /* |
787 | * We have received data on the socket. For an oobinline |
788 | * socket, this might be data _before_ an urgent pointer, |
789 | * in which case we send it to the back end with type==1 |
790 | * (data prior to urgent). |
791 | */ |
792 | if (s->oobinline && s->oobpending) { |
793 | atmark = 1; |
794 | if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark) |
795 | s->oobpending = FALSE; /* clear this indicator */ |
796 | } else |
797 | atmark = 1; |
798 | |
56e5b2db |
799 | ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0); |
c5e438ec |
800 | noise_ultralight(ret); |
801 | if (ret < 0) { |
802 | if (errno == EWOULDBLOCK) { |
803 | break; |
804 | } |
805 | } |
806 | if (ret < 0) { |
807 | return plug_closing(s->plug, error_string(errno), errno, 0); |
808 | } else if (0 == ret) { |
809 | return plug_closing(s->plug, NULL, 0, 0); |
810 | } else { |
811 | return plug_receive(s->plug, atmark ? 0 : 1, buf, ret); |
812 | } |
813 | break; |
814 | case 2: /* writable */ |
815 | { |
816 | int bufsize_before, bufsize_after; |
817 | s->writable = 1; |
818 | bufsize_before = s->sending_oob + bufchain_size(&s->output_data); |
819 | try_send(s); |
820 | bufsize_after = s->sending_oob + bufchain_size(&s->output_data); |
821 | if (bufsize_after < bufsize_before) |
822 | plug_sent(s->plug, bufsize_after); |
823 | } |
824 | break; |
825 | } |
826 | |
827 | return 1; |
828 | } |
829 | |
830 | /* |
831 | * Deal with socket errors detected in try_send(). |
832 | */ |
833 | void net_pending_errors(void) |
834 | { |
835 | int i; |
836 | Actual_Socket s; |
837 | |
838 | /* |
839 | * This might be a fiddly business, because it's just possible |
840 | * that handling a pending error on one socket might cause |
841 | * others to be closed. (I can't think of any reason this might |
842 | * happen in current SSH implementation, but to maintain |
843 | * generality of this network layer I'll assume the worst.) |
844 | * |
845 | * So what we'll do is search the socket list for _one_ socket |
846 | * with a pending error, and then handle it, and then search |
847 | * the list again _from the beginning_. Repeat until we make a |
848 | * pass with no socket errors present. That way we are |
849 | * protected against the socket list changing under our feet. |
850 | */ |
851 | |
852 | do { |
853 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
854 | if (s->pending_error) { |
855 | /* |
856 | * An error has occurred on this socket. Pass it to the |
857 | * plug. |
858 | */ |
859 | plug_closing(s->plug, error_string(s->pending_error), |
860 | s->pending_error, 0); |
861 | break; |
862 | } |
863 | } |
864 | } while (s); |
865 | } |
866 | |
867 | /* |
868 | * Each socket abstraction contains a `void *' private field in |
869 | * which the client can keep state. |
870 | */ |
871 | static void sk_tcp_set_private_ptr(Socket sock, void *ptr) |
872 | { |
873 | Actual_Socket s = (Actual_Socket) sock; |
874 | s->private_ptr = ptr; |
875 | } |
876 | |
877 | static void *sk_tcp_get_private_ptr(Socket sock) |
878 | { |
879 | Actual_Socket s = (Actual_Socket) sock; |
880 | return s->private_ptr; |
881 | } |
882 | |
883 | /* |
884 | * Special error values are returned from sk_namelookup and sk_new |
885 | * if there's a problem. These functions extract an error message, |
886 | * or return NULL if there's no problem. |
887 | */ |
888 | char *sk_addr_error(SockAddr addr) |
889 | { |
890 | return addr->error; |
891 | } |
892 | static char *sk_tcp_socket_error(Socket sock) |
893 | { |
894 | Actual_Socket s = (Actual_Socket) sock; |
895 | return s->error; |
896 | } |
897 | |
898 | static void sk_tcp_set_frozen(Socket sock, int is_frozen) |
899 | { |
900 | Actual_Socket s = (Actual_Socket) sock; |
901 | if (s->frozen == is_frozen) |
902 | return; |
903 | s->frozen = is_frozen; |
904 | if (!is_frozen && s->frozen_readable) { |
905 | char c; |
906 | recv(s->s, &c, 1, MSG_PEEK); |
907 | } |
908 | s->frozen_readable = 0; |
909 | } |
910 | |
911 | /* |
912 | * For Unix select()-based frontends: enumerate all sockets |
913 | * currently active, and state whether we currently wish to receive |
914 | * select events on them for reading, writing and exceptional |
915 | * status. |
916 | */ |
917 | static void set_rwx(Actual_Socket s, int *rwx) |
918 | { |
919 | int val = 0; |
920 | if (s->connected && !s->frozen) |
921 | val |= 1 | 4; /* read, except */ |
922 | if (bufchain_size(&s->output_data)) |
923 | val |= 2; /* write */ |
924 | if (s->listener) |
925 | val |= 1; /* read == accept */ |
926 | *rwx = val; |
927 | } |
928 | |
929 | int first_socket(int *state, int *rwx) |
930 | { |
931 | Actual_Socket s; |
932 | *state = 0; |
933 | s = index234(sktree, (*state)++); |
934 | if (s) |
935 | set_rwx(s, rwx); |
936 | return s ? s->s : -1; |
937 | } |
938 | |
939 | int next_socket(int *state, int *rwx) |
940 | { |
941 | Actual_Socket s = index234(sktree, (*state)++); |
942 | if (s) |
943 | set_rwx(s, rwx); |
944 | return s ? s->s : -1; |
945 | } |
946 | |
947 | int net_service_lookup(char *service) |
948 | { |
949 | struct servent *se; |
950 | se = getservbyname(service, NULL); |
951 | if (se != NULL) |
952 | return ntohs(se->s_port); |
953 | else |
954 | return 0; |
955 | } |