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 | |
6ee9b735 |
24 | #define ipv4_is_loopback(addr) (inet_netof(addr) == IN_LOOPBACKNET) |
25 | |
c5e438ec |
26 | struct Socket_tag { |
27 | struct socket_function_table *fn; |
28 | /* the above variable absolutely *must* be the first in this structure */ |
29 | char *error; |
30 | int s; |
31 | Plug plug; |
32 | void *private_ptr; |
33 | bufchain output_data; |
34 | int connected; |
35 | int writable; |
36 | int frozen; /* this causes readability notifications to be ignored */ |
37 | int frozen_readable; /* this means we missed at least one readability |
38 | * notification while we were frozen */ |
39 | int localhost_only; /* for listening sockets */ |
40 | char oobdata[1]; |
41 | int sending_oob; |
42 | int oobpending; /* is there OOB data available to read? */ |
43 | int oobinline; |
44 | int pending_error; /* in case send() returns error */ |
45 | int listener; |
46 | }; |
47 | |
48 | /* |
49 | * We used to typedef struct Socket_tag *Socket. |
50 | * |
51 | * Since we have made the networking abstraction slightly more |
52 | * abstract, Socket no longer means a tcp socket (it could mean |
53 | * an ssl socket). So now we must use Actual_Socket when we know |
54 | * we are talking about a tcp socket. |
55 | */ |
56 | typedef struct Socket_tag *Actual_Socket; |
57 | |
58 | struct SockAddr_tag { |
59 | char *error; |
b7a189f3 |
60 | /* |
61 | * Which address family this address belongs to. AF_INET for |
62 | * IPv4; AF_INET6 for IPv6; AF_UNSPEC indicates that name |
63 | * resolution has not been done and a simple host name is held |
64 | * in this SockAddr structure. |
65 | */ |
c5e438ec |
66 | int family; |
67 | unsigned long address; /* Address IPv4 style. */ |
68 | #ifdef IPV6 |
69 | struct addrinfo *ai; /* Address IPv6 style. */ |
70 | #endif |
b7a189f3 |
71 | char hostname[512]; /* Store an unresolved host name. */ |
c5e438ec |
72 | }; |
73 | |
74 | static tree234 *sktree; |
75 | |
76 | static int cmpfortree(void *av, void *bv) |
77 | { |
78 | Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv; |
79 | int as = a->s, bs = b->s; |
80 | if (as < bs) |
81 | return -1; |
82 | if (as > bs) |
83 | return +1; |
84 | return 0; |
85 | } |
86 | |
87 | static int cmpforsearch(void *av, void *bv) |
88 | { |
89 | Actual_Socket b = (Actual_Socket) bv; |
90 | int as = (int) av, bs = b->s; |
91 | if (as < bs) |
92 | return -1; |
93 | if (as > bs) |
94 | return +1; |
95 | return 0; |
96 | } |
97 | |
98 | void sk_init(void) |
99 | { |
100 | sktree = newtree234(cmpfortree); |
101 | } |
102 | |
103 | void sk_cleanup(void) |
104 | { |
105 | Actual_Socket s; |
106 | int i; |
107 | |
108 | if (sktree) { |
109 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
110 | close(s->s); |
111 | } |
112 | } |
113 | } |
114 | |
115 | char *error_string(int error) |
116 | { |
e266735f |
117 | return strerror(error); |
c5e438ec |
118 | } |
119 | |
e8fa8f62 |
120 | SockAddr sk_namelookup(const char *host, char **canonicalname) |
c5e438ec |
121 | { |
122 | SockAddr ret = smalloc(sizeof(struct SockAddr_tag)); |
123 | unsigned long a; |
124 | struct hostent *h = NULL; |
125 | char realhost[8192]; |
126 | |
127 | /* Clear the structure and default to IPv4. */ |
128 | memset(ret, 0, sizeof(struct SockAddr_tag)); |
129 | ret->family = 0; /* We set this one when we have resolved the host. */ |
130 | *realhost = '\0'; |
131 | ret->error = NULL; |
132 | |
133 | if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
134 | #ifdef IPV6 |
135 | if (getaddrinfo(host, NULL, NULL, &ret->ai) == 0) { |
136 | ret->family = ret->ai->ai_family; |
137 | } else |
138 | #endif |
139 | { |
140 | /* |
141 | * Otherwise use the IPv4-only gethostbyname... (NOTE: |
142 | * we don't use gethostbyname as a fallback!) |
143 | */ |
144 | if (ret->family == 0) { |
145 | /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */ |
146 | if ( (h = gethostbyname(host)) ) |
147 | ret->family = AF_INET; |
148 | } |
8c43874c |
149 | if (ret->family == 0) { |
c5e438ec |
150 | ret->error = (h_errno == HOST_NOT_FOUND || |
151 | h_errno == NO_DATA || |
152 | h_errno == NO_ADDRESS ? "Host does not exist" : |
153 | h_errno == TRY_AGAIN ? |
154 | "Temporary name service failure" : |
155 | "gethostbyname: unknown error"); |
8c43874c |
156 | return ret; |
157 | } |
c5e438ec |
158 | } |
159 | |
160 | #ifdef IPV6 |
161 | /* If we got an address info use that... */ |
162 | if (ret->ai) { |
163 | |
164 | /* Are we in IPv4 fallback mode? */ |
165 | /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */ |
166 | if (ret->family == AF_INET) |
167 | memcpy(&a, |
168 | (char *) &((struct sockaddr_in *) ret->ai-> |
169 | ai_addr)->sin_addr, sizeof(a)); |
170 | |
171 | /* Now let's find that canonicalname... */ |
172 | if (getnameinfo((struct sockaddr *) ret->ai->ai_addr, |
173 | ret->family == |
174 | AF_INET ? sizeof(struct sockaddr_in) : |
175 | sizeof(struct sockaddr_in6), realhost, |
176 | sizeof(realhost), NULL, 0, 0) != 0) { |
177 | strncpy(realhost, host, sizeof(realhost)); |
178 | } |
179 | } |
180 | /* We used the IPv4-only gethostbyname()... */ |
181 | else |
182 | #endif |
183 | { |
184 | memcpy(&a, h->h_addr, sizeof(a)); |
185 | /* This way we are always sure the h->h_name is valid :) */ |
186 | strncpy(realhost, h->h_name, sizeof(realhost)); |
187 | } |
188 | } else { |
189 | /* |
190 | * This must be a numeric IPv4 address because it caused a |
191 | * success return from inet_addr. |
192 | */ |
193 | ret->family = AF_INET; |
194 | strncpy(realhost, host, sizeof(realhost)); |
195 | } |
196 | ret->address = ntohl(a); |
197 | realhost[lenof(realhost)-1] = '\0'; |
198 | *canonicalname = smalloc(1+strlen(realhost)); |
199 | strcpy(*canonicalname, realhost); |
200 | return ret; |
201 | } |
202 | |
e8fa8f62 |
203 | SockAddr sk_nonamelookup(const char *host) |
b7a189f3 |
204 | { |
205 | SockAddr ret = smalloc(sizeof(struct SockAddr_tag)); |
ab0873ab |
206 | ret->error = NULL; |
b7a189f3 |
207 | ret->family = AF_UNSPEC; |
208 | strncpy(ret->hostname, host, lenof(ret->hostname)); |
209 | ret->hostname[lenof(ret->hostname)-1] = '\0'; |
210 | return ret; |
211 | } |
212 | |
c5e438ec |
213 | void sk_getaddr(SockAddr addr, char *buf, int buflen) |
214 | { |
215 | #ifdef IPV6 |
b7a189f3 |
216 | if (addr->family == AF_INET6) { |
217 | FIXME; /* I don't know how to get a text form of an IPv6 address. */ |
218 | } else |
c5e438ec |
219 | #endif |
b7a189f3 |
220 | if (addr->family == AF_INET) { |
c5e438ec |
221 | struct in_addr a; |
222 | a.s_addr = htonl(addr->address); |
223 | strncpy(buf, inet_ntoa(a), buflen); |
b7a189f3 |
224 | buf[buflen-1] = '\0'; |
c5e438ec |
225 | } else { |
b7a189f3 |
226 | assert(addr->family == AF_UNSPEC); |
227 | strncpy(buf, addr->hostname, buflen); |
228 | buf[buflen-1] = '\0'; |
c5e438ec |
229 | } |
c5e438ec |
230 | } |
231 | |
b804e1e5 |
232 | int sk_hostname_is_local(char *name) |
233 | { |
234 | return !strcmp(name, "localhost"); |
235 | } |
236 | |
237 | int sk_address_is_local(SockAddr addr) |
238 | { |
239 | #ifdef IPV6 |
b7a189f3 |
240 | if (addr->family == AF_INET6) { |
241 | FIXME; /* someone who can compile for IPV6 had better do this bit */ |
242 | } else |
b804e1e5 |
243 | #endif |
b7a189f3 |
244 | if (addr->family == AF_INET) { |
b804e1e5 |
245 | struct in_addr a; |
246 | a.s_addr = htonl(addr->address); |
247 | return ipv4_is_loopback(a); |
b804e1e5 |
248 | } else { |
b7a189f3 |
249 | assert(addr->family == AF_UNSPEC); |
250 | return 0; /* we don't know; assume not */ |
b804e1e5 |
251 | } |
b804e1e5 |
252 | } |
253 | |
c5e438ec |
254 | int sk_addrtype(SockAddr addr) |
255 | { |
b7a189f3 |
256 | return (addr->family == AF_INET ? ADDRTYPE_IPV4 : |
257 | #ifdef IPV6 |
258 | addr->family == AF_INET6 ? ADDRTYPE_IPV6 : |
259 | #endif |
260 | ADDRTYPE_NAME); |
c5e438ec |
261 | } |
262 | |
263 | void sk_addrcopy(SockAddr addr, char *buf) |
264 | { |
b7a189f3 |
265 | assert(addr->family != AF_UNSPEC); |
c5e438ec |
266 | #ifdef IPV6 |
b7a189f3 |
267 | if (addr->family == AF_INET6) { |
268 | memcpy(buf, (char*) addr->ai, 16); |
269 | } else |
c5e438ec |
270 | #endif |
b7a189f3 |
271 | if (addr->family == AF_INET) { |
c5e438ec |
272 | struct in_addr a; |
273 | a.s_addr = htonl(addr->address); |
274 | memcpy(buf, (char*) &a.s_addr, 4); |
c5e438ec |
275 | } |
c5e438ec |
276 | } |
277 | |
278 | void sk_addr_free(SockAddr addr) |
279 | { |
280 | sfree(addr); |
281 | } |
282 | |
283 | static Plug sk_tcp_plug(Socket sock, Plug p) |
284 | { |
285 | Actual_Socket s = (Actual_Socket) sock; |
286 | Plug ret = s->plug; |
287 | if (p) |
288 | s->plug = p; |
289 | return ret; |
290 | } |
291 | |
292 | static void sk_tcp_flush(Socket s) |
293 | { |
294 | /* |
295 | * We send data to the socket as soon as we can anyway, |
296 | * so we don't need to do anything here. :-) |
297 | */ |
298 | } |
299 | |
300 | static void sk_tcp_close(Socket s); |
e0e7dff8 |
301 | static int sk_tcp_write(Socket s, const char *data, int len); |
302 | static int sk_tcp_write_oob(Socket s, const char *data, int len); |
c5e438ec |
303 | static void sk_tcp_set_private_ptr(Socket s, void *ptr); |
304 | static void *sk_tcp_get_private_ptr(Socket s); |
305 | static void sk_tcp_set_frozen(Socket s, int is_frozen); |
306 | static char *sk_tcp_socket_error(Socket s); |
307 | |
2f92b717 |
308 | static struct socket_function_table tcp_fn_table = { |
309 | sk_tcp_plug, |
310 | sk_tcp_close, |
311 | sk_tcp_write, |
312 | sk_tcp_write_oob, |
313 | sk_tcp_flush, |
314 | sk_tcp_set_private_ptr, |
315 | sk_tcp_get_private_ptr, |
316 | sk_tcp_set_frozen, |
317 | sk_tcp_socket_error |
318 | }; |
319 | |
c5e438ec |
320 | Socket sk_register(void *sock, Plug plug) |
321 | { |
c5e438ec |
322 | Actual_Socket ret; |
323 | |
324 | /* |
325 | * Create Socket structure. |
326 | */ |
327 | ret = smalloc(sizeof(struct Socket_tag)); |
2f92b717 |
328 | ret->fn = &tcp_fn_table; |
c5e438ec |
329 | ret->error = NULL; |
330 | ret->plug = plug; |
331 | bufchain_init(&ret->output_data); |
332 | ret->writable = 1; /* to start with */ |
333 | ret->sending_oob = 0; |
334 | ret->frozen = 1; |
335 | ret->frozen_readable = 0; |
336 | ret->localhost_only = 0; /* unused, but best init anyway */ |
337 | ret->pending_error = 0; |
338 | ret->oobpending = FALSE; |
339 | ret->listener = 0; |
340 | |
341 | ret->s = (int)sock; |
342 | |
343 | if (ret->s < 0) { |
344 | ret->error = error_string(errno); |
345 | return (Socket) ret; |
346 | } |
347 | |
348 | ret->oobinline = 0; |
349 | |
350 | add234(sktree, ret); |
351 | |
352 | return (Socket) ret; |
353 | } |
354 | |
355 | Socket sk_new(SockAddr addr, int port, int privport, int oobinline, |
356 | int nodelay, Plug plug) |
357 | { |
c5e438ec |
358 | int s; |
359 | #ifdef IPV6 |
360 | struct sockaddr_in6 a6; |
361 | #endif |
362 | struct sockaddr_in a; |
363 | int err; |
364 | Actual_Socket ret; |
365 | short localport; |
366 | |
367 | /* |
368 | * Create Socket structure. |
369 | */ |
370 | ret = smalloc(sizeof(struct Socket_tag)); |
2f92b717 |
371 | ret->fn = &tcp_fn_table; |
c5e438ec |
372 | ret->error = NULL; |
373 | ret->plug = plug; |
374 | bufchain_init(&ret->output_data); |
375 | ret->connected = 0; /* to start with */ |
376 | ret->writable = 0; /* to start with */ |
377 | ret->sending_oob = 0; |
378 | ret->frozen = 0; |
379 | ret->frozen_readable = 0; |
380 | ret->localhost_only = 0; /* unused, but best init anyway */ |
381 | ret->pending_error = 0; |
382 | ret->oobpending = FALSE; |
383 | ret->listener = 0; |
384 | |
385 | /* |
386 | * Open socket. |
387 | */ |
b7a189f3 |
388 | assert(addr->family != AF_UNSPEC); |
c5e438ec |
389 | s = socket(addr->family, SOCK_STREAM, 0); |
390 | ret->s = s; |
391 | |
392 | if (s < 0) { |
393 | ret->error = error_string(errno); |
394 | return (Socket) ret; |
395 | } |
396 | |
397 | ret->oobinline = oobinline; |
398 | if (oobinline) { |
399 | int b = TRUE; |
400 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b)); |
401 | } |
402 | |
403 | if (nodelay) { |
404 | int b = TRUE; |
405 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b)); |
406 | } |
407 | |
408 | /* |
409 | * Bind to local address. |
410 | */ |
411 | if (privport) |
412 | localport = 1023; /* count from 1023 downwards */ |
413 | else |
414 | localport = 0; /* just use port 0 (ie kernel picks) */ |
415 | |
416 | /* Loop round trying to bind */ |
417 | while (1) { |
418 | int retcode; |
419 | |
420 | #ifdef IPV6 |
421 | if (addr->family == AF_INET6) { |
422 | memset(&a6, 0, sizeof(a6)); |
423 | a6.sin6_family = AF_INET6; |
424 | /*a6.sin6_addr = in6addr_any; *//* == 0 */ |
425 | a6.sin6_port = htons(localport); |
426 | } else |
427 | #endif |
428 | { |
429 | a.sin_family = AF_INET; |
430 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
431 | a.sin_port = htons(localport); |
432 | } |
433 | #ifdef IPV6 |
434 | retcode = bind(s, (addr->family == AF_INET6 ? |
435 | (struct sockaddr *) &a6 : |
436 | (struct sockaddr *) &a), |
437 | (addr->family == |
438 | AF_INET6 ? sizeof(a6) : sizeof(a))); |
439 | #else |
440 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
441 | #endif |
442 | if (retcode >= 0) { |
443 | err = 0; |
444 | break; /* done */ |
445 | } else { |
446 | err = errno; |
447 | if (err != EADDRINUSE) /* failed, for a bad reason */ |
448 | break; |
449 | } |
450 | |
451 | if (localport == 0) |
452 | break; /* we're only looping once */ |
453 | localport--; |
454 | if (localport == 0) |
455 | break; /* we might have got to the end */ |
456 | } |
457 | |
458 | if (err) { |
459 | ret->error = error_string(err); |
460 | return (Socket) ret; |
461 | } |
462 | |
463 | /* |
464 | * Connect to remote address. |
465 | */ |
466 | #ifdef IPV6 |
467 | if (addr->family == AF_INET6) { |
468 | memset(&a, 0, sizeof(a)); |
469 | a6.sin6_family = AF_INET6; |
470 | a6.sin6_port = htons((short) port); |
471 | a6.sin6_addr = |
472 | ((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr; |
473 | } else |
474 | #endif |
475 | { |
476 | a.sin_family = AF_INET; |
477 | a.sin_addr.s_addr = htonl(addr->address); |
478 | a.sin_port = htons((short) port); |
479 | } |
480 | |
051dd789 |
481 | { |
482 | int i = 1; |
483 | ioctl(s, FIONBIO, &i); |
484 | } |
485 | |
c5e438ec |
486 | if (( |
487 | #ifdef IPV6 |
488 | connect(s, ((addr->family == AF_INET6) ? |
489 | (struct sockaddr *) &a6 : (struct sockaddr *) &a), |
490 | (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a)) |
491 | #else |
492 | connect(s, (struct sockaddr *) &a, sizeof(a)) |
493 | #endif |
494 | ) < 0) { |
051dd789 |
495 | if ( errno != EINPROGRESS ) { |
c5e438ec |
496 | ret->error = error_string(errno); |
497 | return (Socket) ret; |
498 | } |
499 | } else { |
500 | /* |
501 | * If we _don't_ get EWOULDBLOCK, the connect has completed |
502 | * and we should set the socket as connected and writable. |
503 | */ |
504 | ret->connected = 1; |
505 | ret->writable = 1; |
506 | } |
507 | |
508 | add234(sktree, ret); |
509 | |
510 | return (Socket) ret; |
511 | } |
512 | |
6ee9b735 |
513 | Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only) |
c5e438ec |
514 | { |
c5e438ec |
515 | int s; |
516 | #ifdef IPV6 |
517 | struct sockaddr_in6 a6; |
518 | #endif |
519 | struct sockaddr_in a; |
520 | int err; |
521 | Actual_Socket ret; |
522 | int retcode; |
523 | int on = 1; |
524 | |
525 | /* |
526 | * Create Socket structure. |
527 | */ |
528 | ret = smalloc(sizeof(struct Socket_tag)); |
2f92b717 |
529 | ret->fn = &tcp_fn_table; |
c5e438ec |
530 | ret->error = NULL; |
531 | ret->plug = plug; |
532 | bufchain_init(&ret->output_data); |
533 | ret->writable = 0; /* to start with */ |
534 | ret->sending_oob = 0; |
535 | ret->frozen = 0; |
536 | ret->frozen_readable = 0; |
537 | ret->localhost_only = local_host_only; |
538 | ret->pending_error = 0; |
539 | ret->oobpending = FALSE; |
540 | ret->listener = 1; |
541 | |
542 | /* |
543 | * Open socket. |
544 | */ |
545 | s = socket(AF_INET, SOCK_STREAM, 0); |
546 | ret->s = s; |
547 | |
548 | if (s < 0) { |
549 | ret->error = error_string(errno); |
550 | return (Socket) ret; |
551 | } |
552 | |
553 | ret->oobinline = 0; |
554 | |
555 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on)); |
556 | |
557 | #ifdef IPV6 |
558 | if (addr->family == AF_INET6) { |
559 | memset(&a6, 0, sizeof(a6)); |
560 | a6.sin6_family = AF_INET6; |
6ee9b735 |
561 | /* FIXME: srcaddr is ignored for IPv6, because I (SGT) don't |
562 | * know how to do it. :-) */ |
c5e438ec |
563 | if (local_host_only) |
564 | a6.sin6_addr = in6addr_loopback; |
565 | else |
566 | a6.sin6_addr = in6addr_any; |
567 | a6.sin6_port = htons(port); |
568 | } else |
569 | #endif |
570 | { |
6ee9b735 |
571 | int got_addr = 0; |
c5e438ec |
572 | a.sin_family = AF_INET; |
6ee9b735 |
573 | |
574 | /* |
575 | * Bind to source address. First try an explicitly |
576 | * specified one... |
577 | */ |
578 | if (srcaddr) { |
579 | a.sin_addr.s_addr = inet_addr(srcaddr); |
580 | if (a.sin_addr.s_addr != INADDR_NONE) { |
581 | /* Override localhost_only with specified listen addr. */ |
582 | ret->localhost_only = ipv4_is_loopback(a.sin_addr); |
583 | got_addr = 1; |
584 | } |
585 | } |
586 | |
587 | /* |
588 | * ... and failing that, go with one of the standard ones. |
589 | */ |
590 | if (!got_addr) { |
591 | if (local_host_only) |
592 | a.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
593 | else |
594 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
595 | } |
596 | |
c5e438ec |
597 | a.sin_port = htons((short)port); |
598 | } |
599 | #ifdef IPV6 |
600 | retcode = bind(s, (addr->family == AF_INET6 ? |
601 | (struct sockaddr *) &a6 : |
602 | (struct sockaddr *) &a), |
603 | (addr->family == |
604 | AF_INET6 ? sizeof(a6) : sizeof(a))); |
605 | #else |
606 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
607 | #endif |
608 | if (retcode >= 0) { |
609 | err = 0; |
610 | } else { |
611 | err = errno; |
612 | } |
613 | |
614 | if (err) { |
615 | ret->error = error_string(err); |
616 | return (Socket) ret; |
617 | } |
618 | |
619 | |
620 | if (listen(s, SOMAXCONN) < 0) { |
621 | close(s); |
622 | ret->error = error_string(errno); |
623 | return (Socket) ret; |
624 | } |
625 | |
626 | add234(sktree, ret); |
627 | |
628 | return (Socket) ret; |
629 | } |
630 | |
631 | static void sk_tcp_close(Socket sock) |
632 | { |
633 | Actual_Socket s = (Actual_Socket) sock; |
634 | |
635 | del234(sktree, s); |
636 | close(s->s); |
637 | sfree(s); |
638 | } |
639 | |
2f92b717 |
640 | int sk_getxdmdata(void *sock, unsigned long *ip, int *port) |
641 | { |
642 | Actual_Socket s = (Actual_Socket) sock; |
643 | struct sockaddr_in addr; |
644 | socklen_t addrlen; |
645 | |
646 | /* |
647 | * We must check that this socket really _is_ an Actual_Socket. |
648 | */ |
649 | if (s->fn != &tcp_fn_table) |
650 | return 0; /* failure */ |
651 | |
652 | /* |
653 | * If we ever implement connecting to a local X server through |
654 | * a Unix socket, we return 0xFFFFFFFF for the IP address and |
655 | * our current pid for the port. Bizarre, but such is life. |
656 | */ |
657 | |
658 | addrlen = sizeof(addr); |
659 | if (getsockname(s->s, (struct sockaddr *)&addr, &addrlen) < 0 || |
660 | addr.sin_family != AF_INET) |
661 | return 0; |
662 | |
663 | *ip = ntohl(addr.sin_addr.s_addr); |
664 | *port = ntohs(addr.sin_port); |
665 | |
666 | return 1; |
667 | } |
668 | |
c5e438ec |
669 | /* |
670 | * The function which tries to send on a socket once it's deemed |
671 | * writable. |
672 | */ |
673 | void try_send(Actual_Socket s) |
674 | { |
675 | while (s->sending_oob || bufchain_size(&s->output_data) > 0) { |
676 | int nsent; |
677 | int err; |
678 | void *data; |
679 | int len, urgentflag; |
680 | |
681 | if (s->sending_oob) { |
682 | urgentflag = MSG_OOB; |
683 | len = s->sending_oob; |
684 | data = &s->oobdata; |
685 | } else { |
686 | urgentflag = 0; |
687 | bufchain_prefix(&s->output_data, &data, &len); |
688 | } |
689 | nsent = send(s->s, data, len, urgentflag); |
690 | noise_ultralight(nsent); |
691 | if (nsent <= 0) { |
692 | err = (nsent < 0 ? errno : 0); |
693 | if (err == EWOULDBLOCK) { |
694 | /* |
695 | * Perfectly normal: we've sent all we can for the moment. |
696 | */ |
697 | s->writable = FALSE; |
698 | return; |
699 | } else if (nsent == 0 || |
700 | err == ECONNABORTED || err == ECONNRESET) { |
701 | /* |
702 | * If send() returns CONNABORTED or CONNRESET, we |
703 | * unfortunately can't just call plug_closing(), |
704 | * because it's quite likely that we're currently |
705 | * _in_ a call from the code we'd be calling back |
706 | * to, so we'd have to make half the SSH code |
707 | * reentrant. Instead we flag a pending error on |
708 | * the socket, to be dealt with (by calling |
709 | * plug_closing()) at some suitable future moment. |
710 | */ |
711 | s->pending_error = err; |
712 | return; |
713 | } else { |
714 | /* We're inside the Unix frontend here, so we know |
715 | * that the frontend handle is unnecessary. */ |
716 | logevent(NULL, error_string(err)); |
717 | fatalbox("%s", error_string(err)); |
718 | } |
719 | } else { |
720 | if (s->sending_oob) { |
721 | if (nsent < len) { |
722 | memmove(s->oobdata, s->oobdata+nsent, len-nsent); |
723 | s->sending_oob = len - nsent; |
724 | } else { |
725 | s->sending_oob = 0; |
726 | } |
727 | } else { |
728 | bufchain_consume(&s->output_data, nsent); |
729 | } |
730 | } |
731 | } |
732 | } |
733 | |
e0e7dff8 |
734 | static int sk_tcp_write(Socket sock, const char *buf, int len) |
c5e438ec |
735 | { |
736 | Actual_Socket s = (Actual_Socket) sock; |
737 | |
738 | /* |
739 | * Add the data to the buffer list on the socket. |
740 | */ |
741 | bufchain_add(&s->output_data, buf, len); |
742 | |
743 | /* |
744 | * Now try sending from the start of the buffer list. |
745 | */ |
746 | if (s->writable) |
747 | try_send(s); |
748 | |
749 | return bufchain_size(&s->output_data); |
750 | } |
751 | |
e0e7dff8 |
752 | static int sk_tcp_write_oob(Socket sock, const char *buf, int len) |
c5e438ec |
753 | { |
754 | Actual_Socket s = (Actual_Socket) sock; |
755 | |
756 | /* |
757 | * Replace the buffer list on the socket with the data. |
758 | */ |
759 | bufchain_clear(&s->output_data); |
760 | assert(len <= sizeof(s->oobdata)); |
761 | memcpy(s->oobdata, buf, len); |
762 | s->sending_oob = len; |
763 | |
764 | /* |
765 | * Now try sending from the start of the buffer list. |
766 | */ |
767 | if (s->writable) |
768 | try_send(s); |
769 | |
770 | return s->sending_oob; |
771 | } |
772 | |
773 | int select_result(int fd, int event) |
774 | { |
775 | int ret; |
776 | int err; |
777 | char buf[20480]; /* nice big buffer for plenty of speed */ |
778 | Actual_Socket s; |
779 | u_long atmark; |
780 | |
781 | /* Find the Socket structure */ |
782 | s = find234(sktree, (void *) fd, cmpforsearch); |
783 | if (!s) |
784 | return 1; /* boggle */ |
785 | |
786 | noise_ultralight(event); |
787 | |
788 | switch (event) { |
c5e438ec |
789 | case 4: /* exceptional */ |
790 | if (!s->oobinline) { |
791 | /* |
792 | * On a non-oobinline socket, this indicates that we |
793 | * can immediately perform an OOB read and get back OOB |
794 | * data, which we will send to the back end with |
795 | * type==2 (urgent data). |
796 | */ |
797 | ret = recv(s->s, buf, sizeof(buf), MSG_OOB); |
798 | noise_ultralight(ret); |
799 | if (ret <= 0) { |
800 | char *str = (ret == 0 ? "Internal networking trouble" : |
801 | error_string(errno)); |
802 | /* We're inside the Unix frontend here, so we know |
803 | * that the frontend handle is unnecessary. */ |
804 | logevent(NULL, str); |
805 | fatalbox("%s", str); |
806 | } else { |
807 | return plug_receive(s->plug, 2, buf, ret); |
808 | } |
809 | break; |
810 | } |
811 | |
812 | /* |
813 | * If we reach here, this is an oobinline socket, which |
56e5b2db |
814 | * means we should set s->oobpending and then deal with it |
815 | * when we get called for the readability event (which |
816 | * should also occur). |
c5e438ec |
817 | */ |
818 | s->oobpending = TRUE; |
56e5b2db |
819 | break; |
c5e438ec |
820 | case 1: /* readable; also acceptance */ |
821 | if (s->listener) { |
822 | /* |
823 | * On a listening socket, the readability event means a |
824 | * connection is ready to be accepted. |
825 | */ |
826 | struct sockaddr_in isa; |
827 | int addrlen = sizeof(struct sockaddr_in); |
828 | int t; /* socket of connection */ |
829 | |
830 | memset(&isa, 0, sizeof(struct sockaddr_in)); |
831 | err = 0; |
832 | t = accept(s->s,(struct sockaddr *)&isa,&addrlen); |
833 | if (t < 0) { |
834 | break; |
835 | } |
836 | |
6ee9b735 |
837 | if (s->localhost_only && !ipv4_is_loopback(isa.sin_addr)) { |
c5e438ec |
838 | close(t); /* someone let nonlocal through?! */ |
839 | } else if (plug_accepting(s->plug, (void*)t)) { |
840 | close(t); /* denied or error */ |
841 | } |
842 | break; |
843 | } |
844 | |
845 | /* |
846 | * If we reach here, this is not a listening socket, so |
847 | * readability really means readability. |
848 | */ |
849 | |
850 | /* In the case the socket is still frozen, we don't even bother */ |
851 | if (s->frozen) { |
852 | s->frozen_readable = 1; |
853 | break; |
854 | } |
855 | |
856 | /* |
857 | * We have received data on the socket. For an oobinline |
858 | * socket, this might be data _before_ an urgent pointer, |
859 | * in which case we send it to the back end with type==1 |
860 | * (data prior to urgent). |
861 | */ |
862 | if (s->oobinline && s->oobpending) { |
863 | atmark = 1; |
864 | if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark) |
865 | s->oobpending = FALSE; /* clear this indicator */ |
866 | } else |
867 | atmark = 1; |
868 | |
56e5b2db |
869 | ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0); |
c5e438ec |
870 | noise_ultralight(ret); |
871 | if (ret < 0) { |
872 | if (errno == EWOULDBLOCK) { |
873 | break; |
874 | } |
875 | } |
876 | if (ret < 0) { |
877 | return plug_closing(s->plug, error_string(errno), errno, 0); |
878 | } else if (0 == ret) { |
879 | return plug_closing(s->plug, NULL, 0, 0); |
880 | } else { |
881 | return plug_receive(s->plug, atmark ? 0 : 1, buf, ret); |
882 | } |
883 | break; |
884 | case 2: /* writable */ |
051dd789 |
885 | if (!s->connected) { |
886 | /* |
887 | * select() reports a socket as _writable_ when an |
888 | * asynchronous connection is completed. |
889 | */ |
890 | s->connected = s->writable = 1; |
891 | break; |
892 | } else { |
c5e438ec |
893 | int bufsize_before, bufsize_after; |
894 | s->writable = 1; |
895 | bufsize_before = s->sending_oob + bufchain_size(&s->output_data); |
896 | try_send(s); |
897 | bufsize_after = s->sending_oob + bufchain_size(&s->output_data); |
898 | if (bufsize_after < bufsize_before) |
899 | plug_sent(s->plug, bufsize_after); |
900 | } |
901 | break; |
902 | } |
903 | |
904 | return 1; |
905 | } |
906 | |
907 | /* |
908 | * Deal with socket errors detected in try_send(). |
909 | */ |
910 | void net_pending_errors(void) |
911 | { |
912 | int i; |
913 | Actual_Socket s; |
914 | |
915 | /* |
916 | * This might be a fiddly business, because it's just possible |
917 | * that handling a pending error on one socket might cause |
918 | * others to be closed. (I can't think of any reason this might |
919 | * happen in current SSH implementation, but to maintain |
920 | * generality of this network layer I'll assume the worst.) |
921 | * |
922 | * So what we'll do is search the socket list for _one_ socket |
923 | * with a pending error, and then handle it, and then search |
924 | * the list again _from the beginning_. Repeat until we make a |
925 | * pass with no socket errors present. That way we are |
926 | * protected against the socket list changing under our feet. |
927 | */ |
928 | |
929 | do { |
930 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
931 | if (s->pending_error) { |
932 | /* |
933 | * An error has occurred on this socket. Pass it to the |
934 | * plug. |
935 | */ |
936 | plug_closing(s->plug, error_string(s->pending_error), |
937 | s->pending_error, 0); |
938 | break; |
939 | } |
940 | } |
941 | } while (s); |
942 | } |
943 | |
944 | /* |
945 | * Each socket abstraction contains a `void *' private field in |
946 | * which the client can keep state. |
947 | */ |
948 | static void sk_tcp_set_private_ptr(Socket sock, void *ptr) |
949 | { |
950 | Actual_Socket s = (Actual_Socket) sock; |
951 | s->private_ptr = ptr; |
952 | } |
953 | |
954 | static void *sk_tcp_get_private_ptr(Socket sock) |
955 | { |
956 | Actual_Socket s = (Actual_Socket) sock; |
957 | return s->private_ptr; |
958 | } |
959 | |
960 | /* |
961 | * Special error values are returned from sk_namelookup and sk_new |
962 | * if there's a problem. These functions extract an error message, |
963 | * or return NULL if there's no problem. |
964 | */ |
965 | char *sk_addr_error(SockAddr addr) |
966 | { |
967 | return addr->error; |
968 | } |
969 | static char *sk_tcp_socket_error(Socket sock) |
970 | { |
971 | Actual_Socket s = (Actual_Socket) sock; |
972 | return s->error; |
973 | } |
974 | |
975 | static void sk_tcp_set_frozen(Socket sock, int is_frozen) |
976 | { |
977 | Actual_Socket s = (Actual_Socket) sock; |
978 | if (s->frozen == is_frozen) |
979 | return; |
980 | s->frozen = is_frozen; |
981 | if (!is_frozen && s->frozen_readable) { |
982 | char c; |
983 | recv(s->s, &c, 1, MSG_PEEK); |
984 | } |
985 | s->frozen_readable = 0; |
986 | } |
987 | |
988 | /* |
989 | * For Unix select()-based frontends: enumerate all sockets |
990 | * currently active, and state whether we currently wish to receive |
991 | * select events on them for reading, writing and exceptional |
992 | * status. |
993 | */ |
994 | static void set_rwx(Actual_Socket s, int *rwx) |
995 | { |
996 | int val = 0; |
051dd789 |
997 | if (!s->connected) |
998 | val |= 2; /* write == connect */ |
c5e438ec |
999 | if (s->connected && !s->frozen) |
1000 | val |= 1 | 4; /* read, except */ |
1001 | if (bufchain_size(&s->output_data)) |
1002 | val |= 2; /* write */ |
1003 | if (s->listener) |
1004 | val |= 1; /* read == accept */ |
1005 | *rwx = val; |
1006 | } |
1007 | |
1008 | int first_socket(int *state, int *rwx) |
1009 | { |
1010 | Actual_Socket s; |
1011 | *state = 0; |
1012 | s = index234(sktree, (*state)++); |
1013 | if (s) |
1014 | set_rwx(s, rwx); |
1015 | return s ? s->s : -1; |
1016 | } |
1017 | |
1018 | int next_socket(int *state, int *rwx) |
1019 | { |
1020 | Actual_Socket s = index234(sktree, (*state)++); |
1021 | if (s) |
1022 | set_rwx(s, rwx); |
1023 | return s ? s->s : -1; |
1024 | } |
1025 | |
1026 | int net_service_lookup(char *service) |
1027 | { |
1028 | struct servent *se; |
1029 | se = getservbyname(service, NULL); |
1030 | if (se != NULL) |
1031 | return ntohs(se->s_port); |
1032 | else |
1033 | return 0; |
1034 | } |