Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
d4e5e70b | 5 | /* Copyright (c) University of Cambridge 1995 - 2017 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* Functions for doing things with sockets. With the advent of IPv6 this has | |
9 | got messier, so that it's worth pulling out the code into separate functions | |
4c04137d | 10 | that other parts of Exim can call, especially as there are now several |
059ec3d9 PH |
11 | different places in the code where sockets are used. */ |
12 | ||
13 | ||
14 | #include "exim.h" | |
15 | ||
16 | ||
17 | /************************************************* | |
18 | * Create a socket * | |
19 | *************************************************/ | |
20 | ||
21 | /* Socket creation happens in a number of places so it's packaged here for | |
22 | convenience. | |
23 | ||
24 | Arguments: | |
25 | type SOCK_DGRAM or SOCK_STREAM | |
26 | af AF_INET or AF_INET6 | |
27 | ||
28 | Returns: socket number or -1 on failure | |
29 | */ | |
30 | ||
31 | int | |
32 | ip_socket(int type, int af) | |
33 | { | |
34 | int sock = socket(af, type, 0); | |
35 | if (sock < 0) | |
36 | log_write(0, LOG_MAIN, "IPv%c socket creation failed: %s", | |
37 | (af == AF_INET6)? '6':'4', strerror(errno)); | |
38 | return sock; | |
39 | } | |
40 | ||
41 | ||
42 | ||
43 | ||
44 | #if HAVE_IPV6 | |
45 | /************************************************* | |
46 | * Convert printing address to numeric * | |
47 | *************************************************/ | |
48 | ||
49 | /* This function converts the textual form of an IP address into a numeric form | |
50 | in an appropriate structure in an IPv6 environment. The getaddrinfo() function | |
51 | can (apparently) handle more complicated addresses (e.g. those containing | |
52 | scopes) than inet_pton() in some environments. We use hints to tell it that the | |
53 | input must be a numeric address. | |
54 | ||
55 | However, apparently some operating systems (or libraries) don't support | |
56 | getaddrinfo(), so there is a build-time option to revert to inet_pton() (which | |
57 | does not support scopes). | |
58 | ||
59 | Arguments: | |
60 | address textual form of the address | |
61 | addr where to copy back the answer | |
62 | ||
63 | Returns: nothing - failure provokes a panic-die | |
64 | */ | |
65 | ||
66 | static void | |
a56cc2b8 | 67 | ip_addrinfo(const uschar *address, struct sockaddr_in6 *saddr) |
059ec3d9 PH |
68 | { |
69 | #ifdef IPV6_USE_INET_PTON | |
70 | ||
a56cc2b8 | 71 | if (inet_pton(AF_INET6, CCS address, &saddr->sin6_addr) != 1) |
059ec3d9 PH |
72 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an " |
73 | "IP address", address); | |
74 | saddr->sin6_family = AF_INET6; | |
75 | ||
76 | #else | |
77 | ||
78 | int rc; | |
79 | struct addrinfo hints, *res; | |
80 | memset(&hints, 0, sizeof(hints)); | |
81 | hints.ai_family = AF_INET6; | |
82 | hints.ai_socktype = SOCK_STREAM; | |
83 | hints.ai_flags = AI_NUMERICHOST; | |
a56cc2b8 | 84 | if ((rc = getaddrinfo(CCS address, NULL, &hints, &res)) != 0 || res == NULL) |
059ec3d9 PH |
85 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an " |
86 | "IP address: %s", address, | |
87 | (rc == 0)? "NULL result returned" : gai_strerror(rc)); | |
88 | memcpy(saddr, res->ai_addr, res->ai_addrlen); | |
89 | freeaddrinfo(res); | |
90 | ||
91 | #endif | |
92 | } | |
93 | #endif /* HAVE_IPV6 */ | |
94 | ||
95 | ||
96 | /************************************************* | |
97 | * Bind socket to interface and port * | |
98 | *************************************************/ | |
99 | ||
059ec3d9 | 100 | int |
7eb6c37c | 101 | ip_addr(void * sin_, int af, const uschar * address, int port) |
059ec3d9 | 102 | { |
7eb6c37c | 103 | union sockaddr_46 * sin = sin_; |
69cbeaec | 104 | memset(sin, 0, sizeof(*sin)); |
059ec3d9 PH |
105 | |
106 | /* Setup code when using an IPv6 socket. The wildcard address is ":", to | |
107 | ensure an IPv6 socket is used. */ | |
108 | ||
109 | #if HAVE_IPV6 | |
110 | if (af == AF_INET6) | |
111 | { | |
112 | if (address[0] == ':' && address[1] == 0) | |
113 | { | |
7eb6c37c JH |
114 | sin->v6.sin6_family = AF_INET6; |
115 | sin->v6.sin6_addr = in6addr_any; | |
059ec3d9 PH |
116 | } |
117 | else | |
7eb6c37c JH |
118 | ip_addrinfo(address, &sin->v6); /* Panic-dies on error */ |
119 | sin->v6.sin6_port = htons(port); | |
120 | return sizeof(sin->v6); | |
059ec3d9 PH |
121 | } |
122 | else | |
123 | #else /* HAVE_IPv6 */ | |
124 | af = af; /* Avoid compiler warning */ | |
125 | #endif /* HAVE_IPV6 */ | |
126 | ||
127 | /* Setup code when using IPv4 socket. The wildcard address is "". */ | |
128 | ||
129 | { | |
7eb6c37c JH |
130 | sin->v4.sin_family = AF_INET; |
131 | sin->v4.sin_port = htons(port); | |
132 | sin->v4.sin_addr.s_addr = address[0] == 0 | |
133 | ? (S_ADDR_TYPE)INADDR_ANY | |
134 | : (S_ADDR_TYPE)inet_addr(CS address); | |
135 | return sizeof(sin->v4); | |
059ec3d9 | 136 | } |
7eb6c37c | 137 | } |
059ec3d9 | 138 | |
059ec3d9 | 139 | |
7eb6c37c JH |
140 | |
141 | /* This function binds a socket to a local interface address and port. For a | |
142 | wildcard IPv6 bind, the address is ":". | |
143 | ||
144 | Arguments: | |
145 | sock the socket | |
146 | af AF_INET or AF_INET6 - the socket type | |
147 | address the IP address, in text form | |
148 | port the IP port (host order) | |
149 | ||
150 | Returns: the result of bind() | |
151 | */ | |
152 | ||
153 | int | |
154 | ip_bind(int sock, int af, uschar *address, int port) | |
155 | { | |
156 | union sockaddr_46 sin; | |
157 | int s_len = ip_addr(&sin, af, address, port); | |
059ec3d9 PH |
158 | return bind(sock, (struct sockaddr *)&sin, s_len); |
159 | } | |
160 | ||
161 | ||
162 | ||
163 | /************************************************* | |
164 | * Connect socket to remote host * | |
165 | *************************************************/ | |
166 | ||
167 | /* This function connects a socket to a remote address and port. The socket may | |
d515a917 PH |
168 | or may not have previously been bound to a local interface. The socket is not |
169 | closed, even in cases of error. It is expected that the calling function, which | |
170 | created the socket, will be the one that closes it. | |
059ec3d9 PH |
171 | |
172 | Arguments: | |
173 | sock the socket | |
174 | af AF_INET6 or AF_INET for the socket type | |
175 | address the remote address, in text form | |
176 | port the remote port | |
b1f8e4f8 | 177 | timeout a timeout (zero for indefinite timeout) |
0ab63f3d JH |
178 | fastopen non-null iff TCP_FASTOPEN can be used; may indicate early-data to |
179 | be sent in SYN segment | |
059ec3d9 PH |
180 | |
181 | Returns: 0 on success; -1 on failure, with errno set | |
182 | */ | |
183 | ||
184 | int | |
fb05276a | 185 | ip_connect(int sock, int af, const uschar *address, int port, int timeout, |
0ab63f3d | 186 | const blob * fastopen) |
059ec3d9 PH |
187 | { |
188 | struct sockaddr_in s_in4; | |
189 | struct sockaddr *s_ptr; | |
190 | int s_len, rc, save_errno; | |
191 | ||
192 | /* For an IPv6 address, use an IPv6 sockaddr structure. */ | |
193 | ||
194 | #if HAVE_IPV6 | |
195 | struct sockaddr_in6 s_in6; | |
196 | if (af == AF_INET6) | |
197 | { | |
198 | memset(&s_in6, 0, sizeof(s_in6)); | |
199 | ip_addrinfo(address, &s_in6); /* Panic-dies on error */ | |
200 | s_in6.sin6_port = htons(port); | |
201 | s_ptr = (struct sockaddr *)&s_in6; | |
202 | s_len = sizeof(s_in6); | |
203 | } | |
204 | else | |
205 | #else /* HAVE_IPV6 */ | |
206 | af = af; /* Avoid compiler warning */ | |
207 | #endif /* HAVE_IPV6 */ | |
208 | ||
209 | /* For an IPv4 address, use an IPv4 sockaddr structure, even on a system with | |
210 | IPv6 support. */ | |
211 | ||
212 | { | |
213 | memset(&s_in4, 0, sizeof(s_in4)); | |
214 | s_in4.sin_family = AF_INET; | |
215 | s_in4.sin_port = htons(port); | |
a56cc2b8 | 216 | s_in4.sin_addr.s_addr = (S_ADDR_TYPE)inet_addr(CCS address); |
059ec3d9 PH |
217 | s_ptr = (struct sockaddr *)&s_in4; |
218 | s_len = sizeof(s_in4); | |
219 | } | |
220 | ||
221 | /* If no connection timeout is set, just call connect() without setting a | |
222 | timer, thereby allowing the inbuilt OS timeout to operate. */ | |
223 | ||
af483912 | 224 | callout_address = string_sprintf("[%s]:%d", address, port); |
059ec3d9 PH |
225 | sigalrm_seen = FALSE; |
226 | if (timeout > 0) alarm(timeout); | |
fb05276a | 227 | |
18f1b2f3 | 228 | #if defined(TCP_FASTOPEN) && defined(MSG_FASTOPEN) |
fb05276a JH |
229 | /* TCP Fast Open, if the system has a cookie from a previous call to |
230 | this peer, can send data in the SYN packet. The peer can send data | |
231 | before it gets our ACK of its SYN,ACK - the latter is useful for | |
ac0dcd3f JH |
232 | the SMTP banner. Other (than SMTP) cases of TCP connections can |
233 | possibly use the data-on-syn, so support that too. */ | |
fb05276a JH |
234 | |
235 | if (fastopen) | |
236 | { | |
0ab63f3d | 237 | if ((rc = sendto(sock, fastopen->data, fastopen->len, |
ac0dcd3f | 238 | MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0) |
1ccd5f67 | 239 | /* seen for with-data, experimental TFO option, with-cookie case */ |
8255135b | 240 | /* seen for with-data, proper TFO opt, with-cookie case */ |
ac0dcd3f | 241 | { |
1ccd5f67 JH |
242 | DEBUG(D_transport|D_v) debug_printf("TFO mode connection attempt, %s data\n", |
243 | fastopen->len > 0 ? "with" : "no"); | |
244 | tcp_out_fastopen = fastopen->len > 0 ? 2 : 1; | |
ac0dcd3f | 245 | } |
8255135b | 246 | else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */ |
1ccd5f67 JH |
247 | /* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */ |
248 | /* apparently no visibility of the diffference at this point */ | |
8255135b | 249 | /* seen for with-data, proper TFO opt, cookie-req */ |
1ccd5f67 JH |
250 | /* with netwk delay, post-conn tcp_info sees unacked 1 for R, 2 for C; code in smtp_out.c */ |
251 | /* ? older Experimental TFO option behaviour ? */ | |
252 | { /* queue unsent data */ | |
8255135b JH |
253 | DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n", |
254 | fastopen->len > 0 ? "with" : "no"); | |
ac0dcd3f | 255 | if (!fastopen->data) |
a2673768 | 256 | { |
8255135b | 257 | tcp_out_fastopen = 1; /* we tried; unknown if useful yet */ |
ac0dcd3f | 258 | rc = 0; |
a2673768 | 259 | } |
8255135b JH |
260 | else |
261 | rc = send(sock, fastopen->data, fastopen->len, 0); | |
ac0dcd3f JH |
262 | } |
263 | else if(errno == EOPNOTSUPP) | |
264 | { | |
265 | DEBUG(D_transport) | |
266 | debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); | |
267 | goto legacy_connect; | |
268 | } | |
fb05276a JH |
269 | } |
270 | else | |
271 | #endif | |
0ab63f3d JH |
272 | { |
273 | legacy_connect: | |
274 | if ((rc = connect(sock, s_ptr, s_len)) >= 0) | |
275 | if ( fastopen && fastopen->data && fastopen->len | |
276 | && send(sock, fastopen->data, fastopen->len, 0) < 0) | |
277 | rc = -1; | |
278 | } | |
fb05276a | 279 | |
059ec3d9 PH |
280 | save_errno = errno; |
281 | alarm(0); | |
282 | ||
283 | /* There is a testing facility for simulating a connection timeout, as I | |
284 | can't think of any other way of doing this. It converts a connection refused | |
75e0e026 | 285 | into a timeout if the timeout is set to 999999. */ |
059ec3d9 | 286 | |
a39bd74d | 287 | if (running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999) |
059ec3d9 | 288 | { |
a39bd74d JB |
289 | rc = -1; |
290 | save_errno = EINTR; | |
291 | sigalrm_seen = TRUE; | |
059ec3d9 PH |
292 | } |
293 | ||
294 | /* Success */ | |
295 | ||
055e2cb4 | 296 | if (rc >= 0) |
055e2cb4 | 297 | return 0; |
059ec3d9 PH |
298 | |
299 | /* A failure whose error code is "Interrupted system call" is in fact | |
300 | an externally applied timeout if the signal handler has been run. */ | |
301 | ||
a39bd74d | 302 | errno = save_errno == EINTR && sigalrm_seen ? ETIMEDOUT : save_errno; |
059ec3d9 PH |
303 | return -1; |
304 | } | |
305 | ||
306 | ||
a6d4c44e TF |
307 | |
308 | /************************************************* | |
309 | * Create connected socket to remote host * | |
310 | *************************************************/ | |
311 | ||
b1f8e4f8 JH |
312 | /* Create a socket and connect to host (name or number, ipv6 ok) |
313 | at one of port-range. | |
a6d4c44e | 314 | |
b1f8e4f8 JH |
315 | Arguments: |
316 | type SOCK_DGRAM or SOCK_STREAM | |
317 | af AF_INET6 or AF_INET for the socket type | |
318 | address the remote address, in text form | |
319 | portlo,porthi the remote port range | |
320 | timeout a timeout | |
4a5cbaff | 321 | connhost if not NULL, host_item to be filled in with connection details |
b1f8e4f8 | 322 | errstr pointer for allocated string on error |
4a5cbaff JH |
323 | fastopen with SOCK_STREAM, if non-null, request TCP Fast Open. |
324 | Additionally, optional early-data to send | |
b1f8e4f8 JH |
325 | |
326 | Return: | |
327 | socket fd, or -1 on failure (having allocated an error string) | |
328 | */ | |
329 | int | |
330 | ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi, | |
4a5cbaff | 331 | int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen) |
b1f8e4f8 JH |
332 | { |
333 | int namelen, port; | |
334 | host_item shost; | |
335 | host_item *h; | |
336 | int af = 0, fd, fd4 = -1, fd6 = -1; | |
337 | ||
338 | shost.next = NULL; | |
339 | shost.address = NULL; | |
340 | shost.port = portlo; | |
341 | shost.mx = -1; | |
342 | ||
343 | namelen = Ustrlen(hostname); | |
344 | ||
345 | /* Anything enclosed in [] must be an IP address. */ | |
346 | ||
347 | if (hostname[0] == '[' && | |
348 | hostname[namelen - 1] == ']') | |
349 | { | |
af483912 | 350 | uschar * host = string_copyn(hostname+1, namelen-2); |
b1f8e4f8 JH |
351 | if (string_is_ip_address(host, NULL) == 0) |
352 | { | |
353 | *errstr = string_sprintf("malformed IP address \"%s\"", hostname); | |
354 | return -1; | |
355 | } | |
356 | shost.name = shost.address = host; | |
357 | } | |
358 | ||
359 | /* Otherwise check for an unadorned IP address */ | |
360 | ||
361 | else if (string_is_ip_address(hostname, NULL) != 0) | |
af483912 | 362 | shost.name = shost.address = string_copyn(hostname, namelen); |
b1f8e4f8 JH |
363 | |
364 | /* Otherwise lookup IP address(es) from the name */ | |
365 | ||
366 | else | |
367 | { | |
af483912 | 368 | shost.name = string_copyn(hostname, namelen); |
1f155f8e JH |
369 | if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE, |
370 | NULL, FALSE) != HOST_FOUND) | |
b1f8e4f8 JH |
371 | { |
372 | *errstr = string_sprintf("no IP address found for host %s", shost.name); | |
373 | return -1; | |
374 | } | |
375 | } | |
376 | ||
377 | /* Try to connect to the server - test each IP till one works */ | |
378 | ||
fb05276a | 379 | for (h = &shost; h; h = h->next) |
b1f8e4f8 | 380 | { |
af483912 JH |
381 | fd = Ustrchr(h->address, ':') != 0 |
382 | ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6 | |
383 | : fd4 < 0 ? (fd4 = ip_socket(type, af = AF_INET )) : fd4; | |
b1f8e4f8 JH |
384 | |
385 | if (fd < 0) | |
386 | { | |
387 | *errstr = string_sprintf("failed to create socket: %s", strerror(errno)); | |
388 | goto bad; | |
389 | } | |
390 | ||
391 | for(port = portlo; port <= porthi; port++) | |
6af7e591 | 392 | if (ip_connect(fd, af, h->address, port, timeout, fastopen) == 0) |
b1f8e4f8 JH |
393 | { |
394 | if (fd != fd6) close(fd6); | |
395 | if (fd != fd4) close(fd4); | |
8a512ed5 JH |
396 | if (connhost) |
397 | { | |
b1f8e4f8 JH |
398 | h->port = port; |
399 | *connhost = *h; | |
400 | connhost->next = NULL; | |
401 | } | |
402 | return fd; | |
403 | } | |
404 | } | |
405 | ||
a9764ac5 JH |
406 | *errstr = string_sprintf("failed to connect to any address for %s: %s", |
407 | hostname, strerror(errno)); | |
b1f8e4f8 JH |
408 | |
409 | bad: | |
410 | close(fd4); close(fd6); return -1; | |
411 | } | |
412 | ||
059ec3d9 | 413 | |
4a5cbaff | 414 | /*XXX TFO? */ |
3e60dd41 JH |
415 | int |
416 | ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo) | |
417 | { | |
a39bd74d JB |
418 | int scan; |
419 | uschar hostname[256]; | |
420 | unsigned int portlow, porthigh; | |
421 | ||
422 | /* extract host and port part */ | |
423 | scan = sscanf(CS hostport, "%255s %u-%u", hostname, &portlow, &porthigh); | |
424 | if (scan != 3) | |
425 | { | |
426 | if (scan != 2) | |
427 | { | |
428 | *errstr = string_sprintf("invalid socket '%s'", hostport); | |
429 | return -1; | |
3e60dd41 | 430 | } |
a39bd74d | 431 | porthigh = portlow; |
3e60dd41 JH |
432 | } |
433 | ||
a39bd74d | 434 | return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh, |
4a5cbaff | 435 | tmo, NULL, errstr, NULL); |
3e60dd41 JH |
436 | } |
437 | ||
438 | int | |
439 | ip_unixsocket(const uschar * path, uschar ** errstr) | |
440 | { | |
a39bd74d JB |
441 | int sock; |
442 | struct sockaddr_un server; | |
3e60dd41 | 443 | |
a39bd74d JB |
444 | if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) |
445 | { | |
446 | *errstr = US"can't open UNIX socket."; | |
447 | return -1; | |
3e60dd41 JH |
448 | } |
449 | ||
af483912 | 450 | callout_address = string_copy(path); |
a39bd74d JB |
451 | server.sun_family = AF_UNIX; |
452 | Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1); | |
453 | server.sun_path[sizeof(server.sun_path)-1] = '\0'; | |
454 | if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0) | |
455 | { | |
456 | int err = errno; | |
457 | (void)close(sock); | |
458 | *errstr = string_sprintf("unable to connect to UNIX socket (%s): %s", | |
459 | path, strerror(err)); | |
460 | return -1; | |
461 | } | |
462 | return sock; | |
3e60dd41 JH |
463 | } |
464 | ||
465 | int | |
466 | ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo) | |
467 | { | |
a39bd74d JB |
468 | return *spec == '/' |
469 | ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo); | |
3e60dd41 JH |
470 | } |
471 | ||
059ec3d9 PH |
472 | /************************************************* |
473 | * Set keepalive on a socket * | |
474 | *************************************************/ | |
475 | ||
476 | /* Can be called for both incoming and outgoing sockets. | |
477 | ||
478 | Arguments: | |
479 | sock the socket | |
480 | address the remote host address, for failure logging | |
481 | torf true for outgoing connection, false for incoming | |
482 | ||
483 | Returns: nothing | |
484 | */ | |
485 | ||
486 | void | |
55414b25 | 487 | ip_keepalive(int sock, const uschar *address, BOOL torf) |
059ec3d9 PH |
488 | { |
489 | int fodder = 1; | |
490 | if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, | |
5903c6ff | 491 | US (&fodder), sizeof(fodder)) != 0) |
059ec3d9 PH |
492 | log_write(0, LOG_MAIN, "setsockopt(SO_KEEPALIVE) on connection %s %s " |
493 | "failed: %s", torf? "to":"from", address, strerror(errno)); | |
494 | } | |
495 | ||
496 | ||
497 | ||
498 | /************************************************* | |
499 | * Receive from a socket with timeout * | |
500 | *************************************************/ | |
501 | ||
4e71661f | 502 | /* |
059ec3d9 | 503 | Arguments: |
4e71661f JH |
504 | fd the file descriptor |
505 | timeout the timeout, seconds | |
506 | Returns: TRUE => ready for i/o | |
507 | FALSE => timed out, or other error | |
059ec3d9 | 508 | */ |
4e71661f JH |
509 | BOOL |
510 | fd_ready(int fd, int timeout) | |
059ec3d9 PH |
511 | { |
512 | fd_set select_inset; | |
19050083 | 513 | time_t start_recv = time(NULL); |
c528cec4 | 514 | int time_left = timeout; |
059ec3d9 PH |
515 | int rc; |
516 | ||
85ff3cf9 | 517 | if (time_left <= 0) |
4e71661f JH |
518 | { |
519 | errno = ETIMEDOUT; | |
520 | return FALSE; | |
521 | } | |
059ec3d9 PH |
522 | /* Wait until the socket is ready */ |
523 | ||
a39bd74d | 524 | do |
059ec3d9 | 525 | { |
f2ed27cf | 526 | struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 }; |
059ec3d9 | 527 | FD_ZERO (&select_inset); |
4e71661f | 528 | FD_SET (fd, &select_inset); |
059ec3d9 | 529 | |
0f0c8159 | 530 | /*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/ |
4e71661f | 531 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv); |
059ec3d9 PH |
532 | |
533 | /* If some interrupt arrived, just retry. We presume this to be rare, | |
534 | but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes | |
535 | select() to exit). | |
536 | ||
537 | Aug 2004: Somebody set up a cron job that ran exiwhat every 2 minutes, making | |
538 | the interrupt not at all rare. Since the timeout is typically more than 2 | |
539 | minutes, the effect was to block the timeout completely. To prevent this | |
c528cec4 HSHR |
540 | happening again, we do an explicit time test and adjust the timeout |
541 | accordingly */ | |
059ec3d9 PH |
542 | |
543 | if (rc < 0 && errno == EINTR) | |
544 | { | |
545 | DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n"); | |
85ff3cf9 | 546 | |
c528cec4 | 547 | /* Watch out, 'continue' jumps to the condition, not to the loops top */ |
85ff3cf9 HSHR |
548 | time_left = timeout - (time(NULL) - start_recv); |
549 | if (time_left > 0) continue; | |
059ec3d9 PH |
550 | } |
551 | ||
059ec3d9 PH |
552 | if (rc <= 0) |
553 | { | |
554 | errno = ETIMEDOUT; | |
4e71661f | 555 | return FALSE; |
059ec3d9 PH |
556 | } |
557 | ||
c528cec4 HSHR |
558 | /* Checking the FD_ISSET is not enough, if we're interrupted, the |
559 | select_inset may still contain the 'input'. */ | |
059ec3d9 | 560 | } |
4bd6107d | 561 | while (rc < 0 || !FD_ISSET(fd, &select_inset)); |
4e71661f JH |
562 | return TRUE; |
563 | } | |
564 | ||
565 | /* The timeout is implemented using select(), and we loop to cover select() | |
566 | getting interrupted, and the possibility of select() returning with a positive | |
567 | result but no ready descriptor. Is this in fact possible? | |
568 | ||
569 | Arguments: | |
570 | sock the socket | |
571 | buffer to read into | |
572 | bufsize the buffer size | |
573 | timeout the timeout | |
574 | ||
575 | Returns: > 0 => that much data read | |
576 | <= 0 on error or EOF; errno set - zero for EOF | |
577 | */ | |
578 | ||
579 | int | |
580 | ip_recv(int sock, uschar *buffer, int buffsize, int timeout) | |
581 | { | |
582 | int rc; | |
583 | ||
584 | if (!fd_ready(sock, timeout)) | |
585 | return -1; | |
059ec3d9 PH |
586 | |
587 | /* The socket is ready, read from it (via TLS if it's active). On EOF (i.e. | |
588 | close down of the connection), set errno to zero; otherwise leave it alone. */ | |
589 | ||
590 | #ifdef SUPPORT_TLS | |
817d9f57 JH |
591 | if (tls_out.active == sock) |
592 | rc = tls_read(FALSE, buffer, buffsize); | |
593 | else if (tls_in.active == sock) | |
594 | rc = tls_read(TRUE, buffer, buffsize); | |
059ec3d9 PH |
595 | else |
596 | #endif | |
597 | rc = recv(sock, buffer, buffsize, 0); | |
598 | ||
599 | if (rc > 0) return rc; | |
600 | if (rc == 0) errno = 0; | |
601 | return -1; | |
602 | } | |
603 | ||
604 | ||
9e4f5962 PP |
605 | |
606 | ||
13363eba PP |
607 | /************************************************* |
608 | * Lookup address family of potential socket * | |
609 | *************************************************/ | |
610 | ||
611 | /* Given a file-descriptor, check to see if it's a socket and, if so, | |
612 | return the address family; detects IPv4 vs IPv6. If not a socket then | |
613 | return -1. | |
614 | ||
615 | The value 0 is typically AF_UNSPEC, which should not be seen on a connected | |
616 | fd. If the return is -1, the errno will be from getsockname(); probably | |
617 | ENOTSOCK or ECONNRESET. | |
618 | ||
619 | Arguments: socket-or-not fd | |
620 | Returns: address family or -1 | |
621 | */ | |
622 | ||
623 | int | |
624 | ip_get_address_family(int fd) | |
625 | { | |
626 | struct sockaddr_storage ss; | |
627 | socklen_t sslen = sizeof(ss); | |
628 | ||
629 | if (getsockname(fd, (struct sockaddr *) &ss, &sslen) < 0) | |
630 | return -1; | |
631 | ||
632 | return (int) ss.ss_family; | |
633 | } | |
634 | ||
635 | ||
636 | ||
637 | ||
9e4f5962 PP |
638 | /************************************************* |
639 | * Lookup DSCP settings for a socket * | |
640 | *************************************************/ | |
641 | ||
642 | struct dscp_name_tableentry { | |
643 | const uschar *name; | |
644 | int value; | |
645 | }; | |
646 | /* Keep both of these tables sorted! */ | |
647 | static struct dscp_name_tableentry dscp_table[] = { | |
648 | #ifdef IPTOS_DSCP_AF11 | |
36a3ae5f PP |
649 | { CUS"af11", IPTOS_DSCP_AF11 }, |
650 | { CUS"af12", IPTOS_DSCP_AF12 }, | |
651 | { CUS"af13", IPTOS_DSCP_AF13 }, | |
652 | { CUS"af21", IPTOS_DSCP_AF21 }, | |
653 | { CUS"af22", IPTOS_DSCP_AF22 }, | |
654 | { CUS"af23", IPTOS_DSCP_AF23 }, | |
655 | { CUS"af31", IPTOS_DSCP_AF31 }, | |
656 | { CUS"af32", IPTOS_DSCP_AF32 }, | |
657 | { CUS"af33", IPTOS_DSCP_AF33 }, | |
658 | { CUS"af41", IPTOS_DSCP_AF41 }, | |
659 | { CUS"af42", IPTOS_DSCP_AF42 }, | |
660 | { CUS"af43", IPTOS_DSCP_AF43 }, | |
661 | { CUS"ef", IPTOS_DSCP_EF }, | |
9e4f5962 PP |
662 | #endif |
663 | #ifdef IPTOS_LOWCOST | |
36a3ae5f | 664 | { CUS"lowcost", IPTOS_LOWCOST }, |
9e4f5962 | 665 | #endif |
36a3ae5f | 666 | { CUS"lowdelay", IPTOS_LOWDELAY }, |
9e4f5962 | 667 | #ifdef IPTOS_MINCOST |
36a3ae5f | 668 | { CUS"mincost", IPTOS_MINCOST }, |
9e4f5962 | 669 | #endif |
36a3ae5f PP |
670 | { CUS"reliability", IPTOS_RELIABILITY }, |
671 | { CUS"throughput", IPTOS_THROUGHPUT } | |
9e4f5962 PP |
672 | }; |
673 | static int dscp_table_size = | |
674 | sizeof(dscp_table) / sizeof(struct dscp_name_tableentry); | |
675 | ||
676 | /* DSCP values change by protocol family, and so do the options used for | |
2a1b36b3 PP |
677 | setsockopt(); this utility does all the lookups. It takes an unexpanded |
678 | option string, expands it, strips off affix whitespace, then checks if it's | |
679 | a number. If all of what's left is a number, then that's how the option will | |
680 | be parsed and success/failure is a range check. If it's not all a number, | |
681 | then it must be a supported keyword. | |
9e4f5962 PP |
682 | |
683 | Arguments: | |
684 | dscp_name a string, so far unvalidated | |
685 | af address_family in use | |
686 | level setsockopt level to use | |
687 | optname setsockopt name to use | |
688 | dscp_value value for dscp_name | |
689 | ||
690 | Returns: TRUE if okay to setsockopt(), else FALSE | |
2a1b36b3 PP |
691 | |
692 | *level and *optname may be set even if FALSE is returned | |
9e4f5962 PP |
693 | */ |
694 | ||
695 | BOOL | |
696 | dscp_lookup(const uschar *dscp_name, int af, | |
697 | int *level, int *optname, int *dscp_value) | |
698 | { | |
2a1b36b3 | 699 | uschar *dscp_lookup, *p; |
9e4f5962 | 700 | int first, last; |
2a1b36b3 | 701 | long rawlong; |
9e4f5962 PP |
702 | |
703 | if (af == AF_INET) | |
704 | { | |
705 | *level = IPPROTO_IP; | |
706 | *optname = IP_TOS; | |
707 | } | |
bb7b9411 | 708 | #if HAVE_IPV6 && defined(IPV6_TCLASS) |
9e4f5962 PP |
709 | else if (af == AF_INET6) |
710 | { | |
711 | *level = IPPROTO_IPV6; | |
712 | *optname = IPV6_TCLASS; | |
713 | } | |
b301a50b | 714 | #endif |
9e4f5962 PP |
715 | else |
716 | { | |
717 | DEBUG(D_transport) | |
718 | debug_printf("Unhandled address family %d in dscp_lookup()\n", af); | |
719 | return FALSE; | |
720 | } | |
721 | if (!dscp_name) | |
722 | { | |
723 | DEBUG(D_transport) | |
724 | debug_printf("[empty DSCP]\n"); | |
725 | return FALSE; | |
726 | } | |
727 | dscp_lookup = expand_string(US dscp_name); | |
728 | if (dscp_lookup == NULL || *dscp_lookup == '\0') | |
729 | return FALSE; | |
730 | ||
2a1b36b3 PP |
731 | p = dscp_lookup + Ustrlen(dscp_lookup) - 1; |
732 | while (isspace(*p)) *p-- = '\0'; | |
733 | while (isspace(*dscp_lookup) && dscp_lookup < p) dscp_lookup++; | |
734 | if (*dscp_lookup == '\0') | |
735 | return FALSE; | |
736 | ||
737 | rawlong = Ustrtol(dscp_lookup, &p, 0); | |
738 | if (p != dscp_lookup && *p == '\0') | |
739 | { | |
740 | /* We have six bits available, which will end up shifted to fit in 0xFC mask. | |
741 | RFC 2597 defines the values unshifted. */ | |
742 | if (rawlong < 0 || rawlong > 0x3F) | |
743 | { | |
744 | DEBUG(D_transport) | |
745 | debug_printf("DSCP value %ld out of range, ignored.\n", rawlong); | |
746 | return FALSE; | |
747 | } | |
748 | *dscp_value = rawlong << 2; | |
749 | return TRUE; | |
750 | } | |
751 | ||
9e4f5962 PP |
752 | first = 0; |
753 | last = dscp_table_size; | |
754 | while (last > first) | |
755 | { | |
756 | int middle = (first + last)/2; | |
757 | int c = Ustrcmp(dscp_lookup, dscp_table[middle].name); | |
758 | if (c == 0) | |
759 | { | |
760 | *dscp_value = dscp_table[middle].value; | |
761 | return TRUE; | |
762 | } | |
763 | else if (c > 0) | |
9e4f5962 | 764 | first = middle + 1; |
9e4f5962 | 765 | else |
9e4f5962 | 766 | last = middle; |
9e4f5962 PP |
767 | } |
768 | return FALSE; | |
769 | } | |
770 | ||
36a3ae5f PP |
771 | void |
772 | dscp_list_to_stream(FILE *stream) | |
773 | { | |
774 | int i; | |
775 | for (i=0; i < dscp_table_size; ++i) | |
776 | fprintf(stream, "%s\n", dscp_table[i].name); | |
777 | } | |
778 | ||
9e4f5962 | 779 | |
059ec3d9 | 780 | /* End of ip.c */ |
8a512ed5 JH |
781 | /* vi: aw ai sw=2 |
782 | */ |