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 */ |
cbe2d68f |
29 | const char *error; |
c5e438ec |
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 { |
cbe2d68f |
59 | const 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; |
c5e438ec |
67 | #ifdef IPV6 |
68 | struct addrinfo *ai; /* Address IPv6 style. */ |
792c5eb5 |
69 | #else |
70 | unsigned long address; /* Address IPv4 style. */ |
c5e438ec |
71 | #endif |
b7a189f3 |
72 | char hostname[512]; /* Store an unresolved host name. */ |
c5e438ec |
73 | }; |
74 | |
75 | static tree234 *sktree; |
76 | |
0ff9ea38 |
77 | static void uxsel_tell(Actual_Socket s); |
78 | |
c5e438ec |
79 | static int cmpfortree(void *av, void *bv) |
80 | { |
81 | Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv; |
82 | int as = a->s, bs = b->s; |
83 | if (as < bs) |
84 | return -1; |
85 | if (as > bs) |
86 | return +1; |
87 | return 0; |
88 | } |
89 | |
90 | static int cmpforsearch(void *av, void *bv) |
91 | { |
92 | Actual_Socket b = (Actual_Socket) bv; |
93 | int as = (int) av, bs = b->s; |
94 | if (as < bs) |
95 | return -1; |
96 | if (as > bs) |
97 | return +1; |
98 | return 0; |
99 | } |
100 | |
101 | void sk_init(void) |
102 | { |
103 | sktree = newtree234(cmpfortree); |
104 | } |
105 | |
106 | void sk_cleanup(void) |
107 | { |
108 | Actual_Socket s; |
109 | int i; |
110 | |
111 | if (sktree) { |
112 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
113 | close(s->s); |
114 | } |
115 | } |
116 | } |
117 | |
cbe2d68f |
118 | const char *error_string(int error) |
c5e438ec |
119 | { |
e266735f |
120 | return strerror(error); |
c5e438ec |
121 | } |
122 | |
e8fa8f62 |
123 | SockAddr sk_namelookup(const char *host, char **canonicalname) |
c5e438ec |
124 | { |
3d88e64d |
125 | SockAddr ret = snew(struct SockAddr_tag); |
792c5eb5 |
126 | #ifdef IPV6 |
127 | struct addrinfo hints; |
128 | int err; |
129 | #else |
c5e438ec |
130 | unsigned long a; |
131 | struct hostent *h = NULL; |
792c5eb5 |
132 | #endif |
c5e438ec |
133 | char realhost[8192]; |
134 | |
135 | /* Clear the structure and default to IPv4. */ |
136 | memset(ret, 0, sizeof(struct SockAddr_tag)); |
137 | ret->family = 0; /* We set this one when we have resolved the host. */ |
138 | *realhost = '\0'; |
139 | ret->error = NULL; |
140 | |
c5e438ec |
141 | #ifdef IPV6 |
792c5eb5 |
142 | hints.ai_flags = AI_CANONNAME; |
143 | hints.ai_family = AF_UNSPEC; |
144 | hints.ai_socktype = 0; |
145 | hints.ai_protocol = 0; |
146 | hints.ai_addrlen = 0; |
147 | hints.ai_addr = NULL; |
148 | hints.ai_canonname = NULL; |
149 | hints.ai_next = NULL; |
150 | err = getaddrinfo(host, NULL, NULL, &ret->ai); |
151 | if (err != 0) { |
152 | ret->error = gai_strerror(err); |
153 | return ret; |
154 | } |
155 | ret->family = ret->ai->ai_family; |
156 | *realhost = '\0'; |
157 | if (ret->ai->ai_canonname != NULL) |
158 | strncat(realhost, ret->ai->ai_canonname, sizeof(realhost) - 1); |
159 | else |
160 | strncat(realhost, host, sizeof(realhost) - 1); |
161 | #else |
162 | if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) { |
163 | /* |
164 | * Otherwise use the IPv4-only gethostbyname... (NOTE: |
165 | * we don't use gethostbyname as a fallback!) |
166 | */ |
167 | if (ret->family == 0) { |
c5e438ec |
168 | /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */ |
169 | if ( (h = gethostbyname(host)) ) |
792c5eb5 |
170 | ret->family = AF_INET; |
171 | } |
172 | if (ret->family == 0) { |
c5e438ec |
173 | ret->error = (h_errno == HOST_NOT_FOUND || |
792c5eb5 |
174 | h_errno == NO_DATA || |
175 | h_errno == NO_ADDRESS ? "Host does not exist" : |
176 | h_errno == TRY_AGAIN ? |
177 | "Temporary name service failure" : |
178 | "gethostbyname: unknown error"); |
8c43874c |
179 | return ret; |
c5e438ec |
180 | } |
792c5eb5 |
181 | memcpy(&a, h->h_addr, sizeof(a)); |
182 | /* This way we are always sure the h->h_name is valid :) */ |
183 | strncpy(realhost, h->h_name, sizeof(realhost)); |
c5e438ec |
184 | } else { |
185 | /* |
186 | * This must be a numeric IPv4 address because it caused a |
187 | * success return from inet_addr. |
188 | */ |
189 | ret->family = AF_INET; |
190 | strncpy(realhost, host, sizeof(realhost)); |
191 | } |
192 | ret->address = ntohl(a); |
792c5eb5 |
193 | #endif |
c5e438ec |
194 | realhost[lenof(realhost)-1] = '\0'; |
3d88e64d |
195 | *canonicalname = snewn(1+strlen(realhost), char); |
c5e438ec |
196 | strcpy(*canonicalname, realhost); |
197 | return ret; |
198 | } |
199 | |
e8fa8f62 |
200 | SockAddr sk_nonamelookup(const char *host) |
b7a189f3 |
201 | { |
3d88e64d |
202 | SockAddr ret = snew(struct SockAddr_tag); |
ab0873ab |
203 | ret->error = NULL; |
b7a189f3 |
204 | ret->family = AF_UNSPEC; |
205 | strncpy(ret->hostname, host, lenof(ret->hostname)); |
206 | ret->hostname[lenof(ret->hostname)-1] = '\0'; |
207 | return ret; |
208 | } |
209 | |
c5e438ec |
210 | void sk_getaddr(SockAddr addr, char *buf, int buflen) |
211 | { |
792c5eb5 |
212 | |
213 | if (addr->family == AF_UNSPEC) { |
214 | strncpy(buf, addr->hostname, buflen); |
215 | buf[buflen-1] = '\0'; |
216 | } else { |
c5e438ec |
217 | #ifdef IPV6 |
792c5eb5 |
218 | if (getnameinfo(addr->ai->ai_addr, addr->ai->ai_addrlen, buf, buflen, |
219 | NULL, 0, NI_NUMERICHOST) != 0) { |
220 | buf[0] = '\0'; |
221 | strncat(buf, "<unknown>", buflen - 1); |
222 | } |
223 | #else |
c5e438ec |
224 | struct in_addr a; |
792c5eb5 |
225 | assert(addr->family == AF_INET); |
c5e438ec |
226 | a.s_addr = htonl(addr->address); |
227 | strncpy(buf, inet_ntoa(a), buflen); |
b7a189f3 |
228 | buf[buflen-1] = '\0'; |
792c5eb5 |
229 | #endif |
c5e438ec |
230 | } |
c5e438ec |
231 | } |
232 | |
b804e1e5 |
233 | int sk_hostname_is_local(char *name) |
234 | { |
235 | return !strcmp(name, "localhost"); |
236 | } |
237 | |
238 | int sk_address_is_local(SockAddr addr) |
239 | { |
792c5eb5 |
240 | |
241 | if (addr->family == AF_UNSPEC) |
242 | return 0; /* we don't know; assume not */ |
243 | else { |
b804e1e5 |
244 | #ifdef IPV6 |
792c5eb5 |
245 | if (addr->family == AF_INET) |
246 | return ipv4_is_loopback( |
247 | ((struct sockaddr_in *)addr->ai->ai_addr)->sin_addr); |
248 | else if (addr->family == AF_INET6) |
249 | return IN6_IS_ADDR_LOOPBACK( |
250 | &((struct sockaddr_in6 *)addr->ai->ai_addr)->sin6_addr); |
251 | else |
252 | return 0; |
253 | #else |
b804e1e5 |
254 | struct in_addr a; |
792c5eb5 |
255 | assert(addr->family == AF_INET); |
b804e1e5 |
256 | a.s_addr = htonl(addr->address); |
257 | return ipv4_is_loopback(a); |
792c5eb5 |
258 | #endif |
b804e1e5 |
259 | } |
b804e1e5 |
260 | } |
261 | |
c5e438ec |
262 | int sk_addrtype(SockAddr addr) |
263 | { |
b7a189f3 |
264 | return (addr->family == AF_INET ? ADDRTYPE_IPV4 : |
265 | #ifdef IPV6 |
266 | addr->family == AF_INET6 ? ADDRTYPE_IPV6 : |
267 | #endif |
268 | ADDRTYPE_NAME); |
c5e438ec |
269 | } |
270 | |
271 | void sk_addrcopy(SockAddr addr, char *buf) |
272 | { |
792c5eb5 |
273 | |
c5e438ec |
274 | #ifdef IPV6 |
792c5eb5 |
275 | if (addr->family == AF_INET) |
276 | memcpy(buf, &((struct sockaddr_in *)addr->ai->ai_addr)->sin_addr, |
277 | sizeof(struct in_addr)); |
278 | else if (addr->family == AF_INET6) |
279 | memcpy(buf, &((struct sockaddr_in6 *)addr->ai->ai_addr)->sin6_addr, |
280 | sizeof(struct in6_addr)); |
281 | else |
282 | assert(FALSE); |
283 | #else |
284 | struct in_addr a; |
285 | |
286 | assert(addr->family == AF_INET); |
287 | a.s_addr = htonl(addr->address); |
288 | memcpy(buf, (char*) &a.s_addr, 4); |
c5e438ec |
289 | #endif |
c5e438ec |
290 | } |
291 | |
292 | void sk_addr_free(SockAddr addr) |
293 | { |
792c5eb5 |
294 | |
295 | #ifdef IPV6 |
296 | if (addr->ai != NULL) |
297 | freeaddrinfo(addr->ai); |
298 | #endif |
c5e438ec |
299 | sfree(addr); |
300 | } |
301 | |
302 | static Plug sk_tcp_plug(Socket sock, Plug p) |
303 | { |
304 | Actual_Socket s = (Actual_Socket) sock; |
305 | Plug ret = s->plug; |
306 | if (p) |
307 | s->plug = p; |
308 | return ret; |
309 | } |
310 | |
311 | static void sk_tcp_flush(Socket s) |
312 | { |
313 | /* |
314 | * We send data to the socket as soon as we can anyway, |
315 | * so we don't need to do anything here. :-) |
316 | */ |
317 | } |
318 | |
319 | static void sk_tcp_close(Socket s); |
e0e7dff8 |
320 | static int sk_tcp_write(Socket s, const char *data, int len); |
321 | static int sk_tcp_write_oob(Socket s, const char *data, int len); |
c5e438ec |
322 | static void sk_tcp_set_private_ptr(Socket s, void *ptr); |
323 | static void *sk_tcp_get_private_ptr(Socket s); |
324 | static void sk_tcp_set_frozen(Socket s, int is_frozen); |
cbe2d68f |
325 | static const char *sk_tcp_socket_error(Socket s); |
c5e438ec |
326 | |
2f92b717 |
327 | static struct socket_function_table tcp_fn_table = { |
328 | sk_tcp_plug, |
329 | sk_tcp_close, |
330 | sk_tcp_write, |
331 | sk_tcp_write_oob, |
332 | sk_tcp_flush, |
333 | sk_tcp_set_private_ptr, |
334 | sk_tcp_get_private_ptr, |
335 | sk_tcp_set_frozen, |
336 | sk_tcp_socket_error |
337 | }; |
338 | |
c5e438ec |
339 | Socket sk_register(void *sock, Plug plug) |
340 | { |
c5e438ec |
341 | Actual_Socket ret; |
342 | |
343 | /* |
344 | * Create Socket structure. |
345 | */ |
3d88e64d |
346 | ret = snew(struct Socket_tag); |
2f92b717 |
347 | ret->fn = &tcp_fn_table; |
c5e438ec |
348 | ret->error = NULL; |
349 | ret->plug = plug; |
350 | bufchain_init(&ret->output_data); |
351 | ret->writable = 1; /* to start with */ |
352 | ret->sending_oob = 0; |
353 | ret->frozen = 1; |
354 | ret->frozen_readable = 0; |
355 | ret->localhost_only = 0; /* unused, but best init anyway */ |
356 | ret->pending_error = 0; |
357 | ret->oobpending = FALSE; |
358 | ret->listener = 0; |
359 | |
360 | ret->s = (int)sock; |
361 | |
362 | if (ret->s < 0) { |
363 | ret->error = error_string(errno); |
364 | return (Socket) ret; |
365 | } |
366 | |
367 | ret->oobinline = 0; |
368 | |
0ff9ea38 |
369 | uxsel_tell(ret); |
c5e438ec |
370 | add234(sktree, ret); |
371 | |
372 | return (Socket) ret; |
373 | } |
374 | |
375 | Socket sk_new(SockAddr addr, int port, int privport, int oobinline, |
376 | int nodelay, Plug plug) |
377 | { |
c5e438ec |
378 | int s; |
379 | #ifdef IPV6 |
380 | struct sockaddr_in6 a6; |
381 | #endif |
382 | struct sockaddr_in a; |
383 | int err; |
384 | Actual_Socket ret; |
385 | short localport; |
4b70e70e |
386 | int fl; |
c5e438ec |
387 | |
388 | /* |
389 | * Create Socket structure. |
390 | */ |
3d88e64d |
391 | ret = snew(struct Socket_tag); |
2f92b717 |
392 | ret->fn = &tcp_fn_table; |
c5e438ec |
393 | ret->error = NULL; |
394 | ret->plug = plug; |
395 | bufchain_init(&ret->output_data); |
396 | ret->connected = 0; /* to start with */ |
397 | ret->writable = 0; /* to start with */ |
398 | ret->sending_oob = 0; |
399 | ret->frozen = 0; |
400 | ret->frozen_readable = 0; |
401 | ret->localhost_only = 0; /* unused, but best init anyway */ |
402 | ret->pending_error = 0; |
403 | ret->oobpending = FALSE; |
404 | ret->listener = 0; |
405 | |
406 | /* |
407 | * Open socket. |
408 | */ |
b7a189f3 |
409 | assert(addr->family != AF_UNSPEC); |
c5e438ec |
410 | s = socket(addr->family, SOCK_STREAM, 0); |
411 | ret->s = s; |
412 | |
413 | if (s < 0) { |
414 | ret->error = error_string(errno); |
415 | return (Socket) ret; |
416 | } |
417 | |
418 | ret->oobinline = oobinline; |
419 | if (oobinline) { |
420 | int b = TRUE; |
421 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b)); |
422 | } |
423 | |
424 | if (nodelay) { |
425 | int b = TRUE; |
426 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b)); |
427 | } |
428 | |
429 | /* |
430 | * Bind to local address. |
431 | */ |
432 | if (privport) |
433 | localport = 1023; /* count from 1023 downwards */ |
434 | else |
435 | localport = 0; /* just use port 0 (ie kernel picks) */ |
436 | |
437 | /* Loop round trying to bind */ |
438 | while (1) { |
439 | int retcode; |
440 | |
441 | #ifdef IPV6 |
442 | if (addr->family == AF_INET6) { |
792c5eb5 |
443 | /* XXX use getaddrinfo to get a local address? */ |
c5e438ec |
444 | a6.sin6_family = AF_INET6; |
792c5eb5 |
445 | a6.sin6_addr = in6addr_any; |
c5e438ec |
446 | a6.sin6_port = htons(localport); |
792c5eb5 |
447 | retcode = bind(s, (struct sockaddr *) &a6, sizeof(a6)); |
c5e438ec |
448 | } else |
449 | #endif |
450 | { |
792c5eb5 |
451 | assert(addr->family == AF_INET); |
c5e438ec |
452 | a.sin_family = AF_INET; |
453 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
454 | a.sin_port = htons(localport); |
792c5eb5 |
455 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
c5e438ec |
456 | } |
c5e438ec |
457 | if (retcode >= 0) { |
458 | err = 0; |
459 | break; /* done */ |
460 | } else { |
461 | err = errno; |
462 | if (err != EADDRINUSE) /* failed, for a bad reason */ |
463 | break; |
464 | } |
465 | |
466 | if (localport == 0) |
467 | break; /* we're only looping once */ |
468 | localport--; |
469 | if (localport == 0) |
470 | break; /* we might have got to the end */ |
471 | } |
472 | |
473 | if (err) { |
474 | ret->error = error_string(err); |
475 | return (Socket) ret; |
476 | } |
477 | |
478 | /* |
479 | * Connect to remote address. |
480 | */ |
481 | #ifdef IPV6 |
792c5eb5 |
482 | /* XXX would be better to have got getaddrinfo() to fill in the port. */ |
483 | if (addr->family == AF_INET) |
484 | ((struct sockaddr_in *)addr->ai->ai_addr)->sin_port = |
485 | htons(port); |
486 | else { |
487 | assert(addr->family == AF_INET6); |
488 | ((struct sockaddr_in *)addr->ai->ai_addr)->sin_port = |
489 | htons(port); |
c5e438ec |
490 | } |
792c5eb5 |
491 | #else |
492 | a.sin_family = AF_INET; |
493 | a.sin_addr.s_addr = htonl(addr->address); |
494 | a.sin_port = htons((short) port); |
495 | #endif |
4b70e70e |
496 | |
497 | fl = fcntl(s, F_GETFL); |
498 | if (fl != -1) |
499 | fcntl(s, F_SETFL, fl | O_NONBLOCK); |
051dd789 |
500 | |
c5e438ec |
501 | if (( |
502 | #ifdef IPV6 |
792c5eb5 |
503 | connect(s, addr->ai->ai_addr, addr->ai->ai_addrlen) |
c5e438ec |
504 | #else |
505 | connect(s, (struct sockaddr *) &a, sizeof(a)) |
506 | #endif |
507 | ) < 0) { |
051dd789 |
508 | if ( errno != EINPROGRESS ) { |
c5e438ec |
509 | ret->error = error_string(errno); |
510 | return (Socket) ret; |
511 | } |
512 | } else { |
513 | /* |
514 | * If we _don't_ get EWOULDBLOCK, the connect has completed |
515 | * and we should set the socket as connected and writable. |
516 | */ |
517 | ret->connected = 1; |
518 | ret->writable = 1; |
519 | } |
520 | |
0ff9ea38 |
521 | uxsel_tell(ret); |
c5e438ec |
522 | add234(sktree, ret); |
523 | |
524 | return (Socket) ret; |
525 | } |
526 | |
6ee9b735 |
527 | Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only) |
c5e438ec |
528 | { |
c5e438ec |
529 | int s; |
530 | #ifdef IPV6 |
792c5eb5 |
531 | #if 0 |
c5e438ec |
532 | struct sockaddr_in6 a6; |
533 | #endif |
792c5eb5 |
534 | struct addrinfo hints, *ai; |
535 | char portstr[6]; |
536 | #endif |
c5e438ec |
537 | struct sockaddr_in a; |
538 | int err; |
539 | Actual_Socket ret; |
540 | int retcode; |
541 | int on = 1; |
542 | |
543 | /* |
544 | * Create Socket structure. |
545 | */ |
3d88e64d |
546 | ret = snew(struct Socket_tag); |
2f92b717 |
547 | ret->fn = &tcp_fn_table; |
c5e438ec |
548 | ret->error = NULL; |
549 | ret->plug = plug; |
550 | bufchain_init(&ret->output_data); |
551 | ret->writable = 0; /* to start with */ |
552 | ret->sending_oob = 0; |
553 | ret->frozen = 0; |
554 | ret->frozen_readable = 0; |
555 | ret->localhost_only = local_host_only; |
556 | ret->pending_error = 0; |
557 | ret->oobpending = FALSE; |
558 | ret->listener = 1; |
559 | |
560 | /* |
561 | * Open socket. |
562 | */ |
563 | s = socket(AF_INET, SOCK_STREAM, 0); |
564 | ret->s = s; |
565 | |
566 | if (s < 0) { |
567 | ret->error = error_string(errno); |
568 | return (Socket) ret; |
569 | } |
570 | |
571 | ret->oobinline = 0; |
572 | |
573 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on)); |
574 | |
575 | #ifdef IPV6 |
792c5eb5 |
576 | hints.ai_flags = AI_NUMERICHOST; |
577 | hints.ai_family = AF_UNSPEC; |
578 | hints.ai_socktype = 0; |
579 | hints.ai_protocol = 0; |
580 | hints.ai_addrlen = 0; |
581 | hints.ai_addr = NULL; |
582 | hints.ai_canonname = NULL; |
583 | hints.ai_next = NULL; |
584 | sprintf(portstr, "%d", port); |
585 | if (srcaddr != NULL && getaddrinfo(srcaddr, portstr, &hints, &ai) == 0) |
586 | retcode = bind(s, ai->ai_addr, ai->ai_addrlen); |
587 | else |
588 | #if 0 |
589 | { |
590 | /* |
591 | * FIXME: Need two listening sockets, in principle, one for v4 |
592 | * and one for v6 |
593 | */ |
c5e438ec |
594 | if (local_host_only) |
595 | a6.sin6_addr = in6addr_loopback; |
596 | else |
597 | a6.sin6_addr = in6addr_any; |
598 | a6.sin6_port = htons(port); |
599 | } else |
600 | #endif |
792c5eb5 |
601 | #endif |
c5e438ec |
602 | { |
6ee9b735 |
603 | int got_addr = 0; |
c5e438ec |
604 | a.sin_family = AF_INET; |
6ee9b735 |
605 | |
606 | /* |
607 | * Bind to source address. First try an explicitly |
608 | * specified one... |
609 | */ |
610 | if (srcaddr) { |
611 | a.sin_addr.s_addr = inet_addr(srcaddr); |
612 | if (a.sin_addr.s_addr != INADDR_NONE) { |
613 | /* Override localhost_only with specified listen addr. */ |
614 | ret->localhost_only = ipv4_is_loopback(a.sin_addr); |
615 | got_addr = 1; |
616 | } |
617 | } |
618 | |
619 | /* |
620 | * ... and failing that, go with one of the standard ones. |
621 | */ |
622 | if (!got_addr) { |
623 | if (local_host_only) |
624 | a.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
625 | else |
626 | a.sin_addr.s_addr = htonl(INADDR_ANY); |
627 | } |
628 | |
c5e438ec |
629 | a.sin_port = htons((short)port); |
792c5eb5 |
630 | retcode = bind(s, (struct sockaddr *) &a, sizeof(a)); |
c5e438ec |
631 | } |
792c5eb5 |
632 | |
c5e438ec |
633 | if (retcode >= 0) { |
634 | err = 0; |
635 | } else { |
636 | err = errno; |
637 | } |
638 | |
639 | if (err) { |
640 | ret->error = error_string(err); |
641 | return (Socket) ret; |
642 | } |
643 | |
644 | |
645 | if (listen(s, SOMAXCONN) < 0) { |
646 | close(s); |
647 | ret->error = error_string(errno); |
648 | return (Socket) ret; |
649 | } |
650 | |
0ff9ea38 |
651 | uxsel_tell(ret); |
c5e438ec |
652 | add234(sktree, ret); |
653 | |
654 | return (Socket) ret; |
655 | } |
656 | |
657 | static void sk_tcp_close(Socket sock) |
658 | { |
659 | Actual_Socket s = (Actual_Socket) sock; |
660 | |
0ff9ea38 |
661 | uxsel_del(s->s); |
c5e438ec |
662 | del234(sktree, s); |
663 | close(s->s); |
664 | sfree(s); |
665 | } |
666 | |
2f92b717 |
667 | int sk_getxdmdata(void *sock, unsigned long *ip, int *port) |
668 | { |
669 | Actual_Socket s = (Actual_Socket) sock; |
670 | struct sockaddr_in addr; |
671 | socklen_t addrlen; |
672 | |
673 | /* |
674 | * We must check that this socket really _is_ an Actual_Socket. |
675 | */ |
676 | if (s->fn != &tcp_fn_table) |
677 | return 0; /* failure */ |
678 | |
679 | /* |
680 | * If we ever implement connecting to a local X server through |
681 | * a Unix socket, we return 0xFFFFFFFF for the IP address and |
682 | * our current pid for the port. Bizarre, but such is life. |
683 | */ |
684 | |
685 | addrlen = sizeof(addr); |
686 | if (getsockname(s->s, (struct sockaddr *)&addr, &addrlen) < 0 || |
687 | addr.sin_family != AF_INET) |
688 | return 0; |
689 | |
690 | *ip = ntohl(addr.sin_addr.s_addr); |
691 | *port = ntohs(addr.sin_port); |
692 | |
693 | return 1; |
694 | } |
695 | |
c5e438ec |
696 | /* |
697 | * The function which tries to send on a socket once it's deemed |
698 | * writable. |
699 | */ |
700 | void try_send(Actual_Socket s) |
701 | { |
702 | while (s->sending_oob || bufchain_size(&s->output_data) > 0) { |
703 | int nsent; |
704 | int err; |
705 | void *data; |
706 | int len, urgentflag; |
707 | |
708 | if (s->sending_oob) { |
709 | urgentflag = MSG_OOB; |
710 | len = s->sending_oob; |
711 | data = &s->oobdata; |
712 | } else { |
713 | urgentflag = 0; |
714 | bufchain_prefix(&s->output_data, &data, &len); |
715 | } |
716 | nsent = send(s->s, data, len, urgentflag); |
717 | noise_ultralight(nsent); |
718 | if (nsent <= 0) { |
719 | err = (nsent < 0 ? errno : 0); |
720 | if (err == EWOULDBLOCK) { |
721 | /* |
722 | * Perfectly normal: we've sent all we can for the moment. |
723 | */ |
724 | s->writable = FALSE; |
725 | return; |
726 | } else if (nsent == 0 || |
727 | err == ECONNABORTED || err == ECONNRESET) { |
728 | /* |
729 | * If send() returns CONNABORTED or CONNRESET, we |
730 | * unfortunately can't just call plug_closing(), |
731 | * because it's quite likely that we're currently |
732 | * _in_ a call from the code we'd be calling back |
733 | * to, so we'd have to make half the SSH code |
734 | * reentrant. Instead we flag a pending error on |
735 | * the socket, to be dealt with (by calling |
736 | * plug_closing()) at some suitable future moment. |
737 | */ |
738 | s->pending_error = err; |
739 | return; |
740 | } else { |
741 | /* We're inside the Unix frontend here, so we know |
742 | * that the frontend handle is unnecessary. */ |
743 | logevent(NULL, error_string(err)); |
744 | fatalbox("%s", error_string(err)); |
745 | } |
746 | } else { |
747 | if (s->sending_oob) { |
748 | if (nsent < len) { |
749 | memmove(s->oobdata, s->oobdata+nsent, len-nsent); |
750 | s->sending_oob = len - nsent; |
751 | } else { |
752 | s->sending_oob = 0; |
753 | } |
754 | } else { |
755 | bufchain_consume(&s->output_data, nsent); |
756 | } |
757 | } |
758 | } |
0ff9ea38 |
759 | uxsel_tell(s); |
c5e438ec |
760 | } |
761 | |
e0e7dff8 |
762 | static int sk_tcp_write(Socket sock, const char *buf, int len) |
c5e438ec |
763 | { |
764 | Actual_Socket s = (Actual_Socket) sock; |
765 | |
766 | /* |
767 | * Add the data to the buffer list on the socket. |
768 | */ |
769 | bufchain_add(&s->output_data, buf, len); |
770 | |
771 | /* |
772 | * Now try sending from the start of the buffer list. |
773 | */ |
774 | if (s->writable) |
775 | try_send(s); |
776 | |
c2a71b0d |
777 | /* |
778 | * Update the select() status to correctly reflect whether or |
779 | * not we should be selecting for write. |
780 | */ |
781 | uxsel_tell(s); |
782 | |
c5e438ec |
783 | return bufchain_size(&s->output_data); |
784 | } |
785 | |
e0e7dff8 |
786 | static int sk_tcp_write_oob(Socket sock, const char *buf, int len) |
c5e438ec |
787 | { |
788 | Actual_Socket s = (Actual_Socket) sock; |
789 | |
790 | /* |
791 | * Replace the buffer list on the socket with the data. |
792 | */ |
793 | bufchain_clear(&s->output_data); |
794 | assert(len <= sizeof(s->oobdata)); |
795 | memcpy(s->oobdata, buf, len); |
796 | s->sending_oob = len; |
797 | |
798 | /* |
799 | * Now try sending from the start of the buffer list. |
800 | */ |
801 | if (s->writable) |
802 | try_send(s); |
803 | |
c2a71b0d |
804 | /* |
805 | * Update the select() status to correctly reflect whether or |
806 | * not we should be selecting for write. |
807 | */ |
808 | uxsel_tell(s); |
809 | |
c5e438ec |
810 | return s->sending_oob; |
811 | } |
812 | |
0ff9ea38 |
813 | static int net_select_result(int fd, int event) |
c5e438ec |
814 | { |
815 | int ret; |
816 | int err; |
817 | char buf[20480]; /* nice big buffer for plenty of speed */ |
818 | Actual_Socket s; |
819 | u_long atmark; |
820 | |
821 | /* Find the Socket structure */ |
822 | s = find234(sktree, (void *) fd, cmpforsearch); |
823 | if (!s) |
824 | return 1; /* boggle */ |
825 | |
826 | noise_ultralight(event); |
827 | |
828 | switch (event) { |
c5e438ec |
829 | case 4: /* exceptional */ |
830 | if (!s->oobinline) { |
831 | /* |
832 | * On a non-oobinline socket, this indicates that we |
833 | * can immediately perform an OOB read and get back OOB |
834 | * data, which we will send to the back end with |
835 | * type==2 (urgent data). |
836 | */ |
837 | ret = recv(s->s, buf, sizeof(buf), MSG_OOB); |
838 | noise_ultralight(ret); |
839 | if (ret <= 0) { |
cbe2d68f |
840 | const char *str = (ret == 0 ? "Internal networking trouble" : |
841 | error_string(errno)); |
c5e438ec |
842 | /* We're inside the Unix frontend here, so we know |
843 | * that the frontend handle is unnecessary. */ |
844 | logevent(NULL, str); |
845 | fatalbox("%s", str); |
846 | } else { |
847 | return plug_receive(s->plug, 2, buf, ret); |
848 | } |
849 | break; |
850 | } |
851 | |
852 | /* |
853 | * If we reach here, this is an oobinline socket, which |
56e5b2db |
854 | * means we should set s->oobpending and then deal with it |
855 | * when we get called for the readability event (which |
856 | * should also occur). |
c5e438ec |
857 | */ |
858 | s->oobpending = TRUE; |
56e5b2db |
859 | break; |
c5e438ec |
860 | case 1: /* readable; also acceptance */ |
861 | if (s->listener) { |
862 | /* |
863 | * On a listening socket, the readability event means a |
864 | * connection is ready to be accepted. |
865 | */ |
866 | struct sockaddr_in isa; |
867 | int addrlen = sizeof(struct sockaddr_in); |
868 | int t; /* socket of connection */ |
869 | |
870 | memset(&isa, 0, sizeof(struct sockaddr_in)); |
871 | err = 0; |
872 | t = accept(s->s,(struct sockaddr *)&isa,&addrlen); |
873 | if (t < 0) { |
874 | break; |
875 | } |
876 | |
6ee9b735 |
877 | if (s->localhost_only && !ipv4_is_loopback(isa.sin_addr)) { |
c5e438ec |
878 | close(t); /* someone let nonlocal through?! */ |
879 | } else if (plug_accepting(s->plug, (void*)t)) { |
880 | close(t); /* denied or error */ |
881 | } |
882 | break; |
883 | } |
884 | |
885 | /* |
886 | * If we reach here, this is not a listening socket, so |
887 | * readability really means readability. |
888 | */ |
889 | |
890 | /* In the case the socket is still frozen, we don't even bother */ |
891 | if (s->frozen) { |
892 | s->frozen_readable = 1; |
893 | break; |
894 | } |
895 | |
896 | /* |
897 | * We have received data on the socket. For an oobinline |
898 | * socket, this might be data _before_ an urgent pointer, |
899 | * in which case we send it to the back end with type==1 |
900 | * (data prior to urgent). |
901 | */ |
902 | if (s->oobinline && s->oobpending) { |
903 | atmark = 1; |
904 | if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark) |
905 | s->oobpending = FALSE; /* clear this indicator */ |
906 | } else |
907 | atmark = 1; |
908 | |
56e5b2db |
909 | ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0); |
c5e438ec |
910 | noise_ultralight(ret); |
911 | if (ret < 0) { |
912 | if (errno == EWOULDBLOCK) { |
913 | break; |
914 | } |
915 | } |
916 | if (ret < 0) { |
917 | return plug_closing(s->plug, error_string(errno), errno, 0); |
918 | } else if (0 == ret) { |
919 | return plug_closing(s->plug, NULL, 0, 0); |
920 | } else { |
921 | return plug_receive(s->plug, atmark ? 0 : 1, buf, ret); |
922 | } |
923 | break; |
924 | case 2: /* writable */ |
051dd789 |
925 | if (!s->connected) { |
926 | /* |
927 | * select() reports a socket as _writable_ when an |
928 | * asynchronous connection is completed. |
929 | */ |
930 | s->connected = s->writable = 1; |
0ff9ea38 |
931 | uxsel_tell(s); |
051dd789 |
932 | break; |
933 | } else { |
c5e438ec |
934 | int bufsize_before, bufsize_after; |
935 | s->writable = 1; |
936 | bufsize_before = s->sending_oob + bufchain_size(&s->output_data); |
937 | try_send(s); |
938 | bufsize_after = s->sending_oob + bufchain_size(&s->output_data); |
939 | if (bufsize_after < bufsize_before) |
940 | plug_sent(s->plug, bufsize_after); |
941 | } |
942 | break; |
943 | } |
944 | |
945 | return 1; |
946 | } |
947 | |
948 | /* |
949 | * Deal with socket errors detected in try_send(). |
950 | */ |
951 | void net_pending_errors(void) |
952 | { |
953 | int i; |
954 | Actual_Socket s; |
955 | |
956 | /* |
957 | * This might be a fiddly business, because it's just possible |
958 | * that handling a pending error on one socket might cause |
959 | * others to be closed. (I can't think of any reason this might |
960 | * happen in current SSH implementation, but to maintain |
961 | * generality of this network layer I'll assume the worst.) |
962 | * |
963 | * So what we'll do is search the socket list for _one_ socket |
964 | * with a pending error, and then handle it, and then search |
965 | * the list again _from the beginning_. Repeat until we make a |
966 | * pass with no socket errors present. That way we are |
967 | * protected against the socket list changing under our feet. |
968 | */ |
969 | |
970 | do { |
971 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
972 | if (s->pending_error) { |
973 | /* |
974 | * An error has occurred on this socket. Pass it to the |
975 | * plug. |
976 | */ |
977 | plug_closing(s->plug, error_string(s->pending_error), |
978 | s->pending_error, 0); |
979 | break; |
980 | } |
981 | } |
982 | } while (s); |
983 | } |
984 | |
985 | /* |
986 | * Each socket abstraction contains a `void *' private field in |
987 | * which the client can keep state. |
988 | */ |
989 | static void sk_tcp_set_private_ptr(Socket sock, void *ptr) |
990 | { |
991 | Actual_Socket s = (Actual_Socket) sock; |
992 | s->private_ptr = ptr; |
993 | } |
994 | |
995 | static void *sk_tcp_get_private_ptr(Socket sock) |
996 | { |
997 | Actual_Socket s = (Actual_Socket) sock; |
998 | return s->private_ptr; |
999 | } |
1000 | |
1001 | /* |
1002 | * Special error values are returned from sk_namelookup and sk_new |
1003 | * if there's a problem. These functions extract an error message, |
1004 | * or return NULL if there's no problem. |
1005 | */ |
cbe2d68f |
1006 | const char *sk_addr_error(SockAddr addr) |
c5e438ec |
1007 | { |
1008 | return addr->error; |
1009 | } |
cbe2d68f |
1010 | static const char *sk_tcp_socket_error(Socket sock) |
c5e438ec |
1011 | { |
1012 | Actual_Socket s = (Actual_Socket) sock; |
1013 | return s->error; |
1014 | } |
1015 | |
1016 | static void sk_tcp_set_frozen(Socket sock, int is_frozen) |
1017 | { |
1018 | Actual_Socket s = (Actual_Socket) sock; |
1019 | if (s->frozen == is_frozen) |
1020 | return; |
1021 | s->frozen = is_frozen; |
1022 | if (!is_frozen && s->frozen_readable) { |
1023 | char c; |
1024 | recv(s->s, &c, 1, MSG_PEEK); |
1025 | } |
1026 | s->frozen_readable = 0; |
0ff9ea38 |
1027 | uxsel_tell(s); |
c5e438ec |
1028 | } |
1029 | |
0ff9ea38 |
1030 | static void uxsel_tell(Actual_Socket s) |
c5e438ec |
1031 | { |
0ff9ea38 |
1032 | int rwx = 0; |
051dd789 |
1033 | if (!s->connected) |
0ff9ea38 |
1034 | rwx |= 2; /* write == connect */ |
c5e438ec |
1035 | if (s->connected && !s->frozen) |
0ff9ea38 |
1036 | rwx |= 1 | 4; /* read, except */ |
c5e438ec |
1037 | if (bufchain_size(&s->output_data)) |
0ff9ea38 |
1038 | rwx |= 2; /* write */ |
c5e438ec |
1039 | if (s->listener) |
0ff9ea38 |
1040 | rwx |= 1; /* read == accept */ |
1041 | uxsel_set(s->s, rwx, net_select_result); |
c5e438ec |
1042 | } |
1043 | |
1044 | int net_service_lookup(char *service) |
1045 | { |
1046 | struct servent *se; |
1047 | se = getservbyname(service, NULL); |
1048 | if (se != NULL) |
1049 | return ntohs(se->s_port); |
1050 | else |
1051 | return 0; |
1052 | } |