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 | ||
10ac8d7f JH |
163 | /************************************************* |
164 | *************************************************/ | |
165 | ||
166 | #ifdef EXIM_TFO_PROBE | |
167 | void | |
168 | tfo_probe(void) | |
169 | { | |
170 | # ifdef TCP_FASTOPEN | |
171 | int sock, backlog = 5; | |
172 | ||
173 | if ( (sock = socket(SOCK_STREAM, AF_INET, 0)) < 0 | |
8de0078c | 174 | && setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &backlog, sizeof(backlog)) |
10ac8d7f JH |
175 | ) |
176 | tcp_fastopen_ok = TRUE; | |
177 | close(sock); | |
178 | # endif | |
179 | } | |
180 | #endif | |
181 | ||
182 | ||
059ec3d9 PH |
183 | /************************************************* |
184 | * Connect socket to remote host * | |
185 | *************************************************/ | |
186 | ||
187 | /* This function connects a socket to a remote address and port. The socket may | |
d515a917 PH |
188 | or may not have previously been bound to a local interface. The socket is not |
189 | closed, even in cases of error. It is expected that the calling function, which | |
190 | created the socket, will be the one that closes it. | |
059ec3d9 PH |
191 | |
192 | Arguments: | |
193 | sock the socket | |
194 | af AF_INET6 or AF_INET for the socket type | |
195 | address the remote address, in text form | |
196 | port the remote port | |
b1f8e4f8 | 197 | timeout a timeout (zero for indefinite timeout) |
10ac8d7f | 198 | fastopen_blob non-null iff TCP_FASTOPEN can be used; may indicate early-data to |
0ab63f3d | 199 | be sent in SYN segment |
059ec3d9 PH |
200 | |
201 | Returns: 0 on success; -1 on failure, with errno set | |
202 | */ | |
203 | ||
204 | int | |
fb05276a | 205 | ip_connect(int sock, int af, const uschar *address, int port, int timeout, |
10ac8d7f | 206 | const blob * fastopen_blob) |
059ec3d9 PH |
207 | { |
208 | struct sockaddr_in s_in4; | |
209 | struct sockaddr *s_ptr; | |
210 | int s_len, rc, save_errno; | |
211 | ||
212 | /* For an IPv6 address, use an IPv6 sockaddr structure. */ | |
213 | ||
214 | #if HAVE_IPV6 | |
215 | struct sockaddr_in6 s_in6; | |
216 | if (af == AF_INET6) | |
217 | { | |
218 | memset(&s_in6, 0, sizeof(s_in6)); | |
219 | ip_addrinfo(address, &s_in6); /* Panic-dies on error */ | |
220 | s_in6.sin6_port = htons(port); | |
221 | s_ptr = (struct sockaddr *)&s_in6; | |
222 | s_len = sizeof(s_in6); | |
223 | } | |
224 | else | |
225 | #else /* HAVE_IPV6 */ | |
226 | af = af; /* Avoid compiler warning */ | |
227 | #endif /* HAVE_IPV6 */ | |
228 | ||
229 | /* For an IPv4 address, use an IPv4 sockaddr structure, even on a system with | |
230 | IPv6 support. */ | |
231 | ||
232 | { | |
233 | memset(&s_in4, 0, sizeof(s_in4)); | |
234 | s_in4.sin_family = AF_INET; | |
235 | s_in4.sin_port = htons(port); | |
a56cc2b8 | 236 | s_in4.sin_addr.s_addr = (S_ADDR_TYPE)inet_addr(CCS address); |
059ec3d9 PH |
237 | s_ptr = (struct sockaddr *)&s_in4; |
238 | s_len = sizeof(s_in4); | |
239 | } | |
240 | ||
241 | /* If no connection timeout is set, just call connect() without setting a | |
242 | timer, thereby allowing the inbuilt OS timeout to operate. */ | |
243 | ||
af483912 | 244 | callout_address = string_sprintf("[%s]:%d", address, port); |
059ec3d9 PH |
245 | sigalrm_seen = FALSE; |
246 | if (timeout > 0) alarm(timeout); | |
fb05276a | 247 | |
18f1b2f3 | 248 | #if defined(TCP_FASTOPEN) && defined(MSG_FASTOPEN) |
fb05276a JH |
249 | /* TCP Fast Open, if the system has a cookie from a previous call to |
250 | this peer, can send data in the SYN packet. The peer can send data | |
251 | before it gets our ACK of its SYN,ACK - the latter is useful for | |
ac0dcd3f JH |
252 | the SMTP banner. Other (than SMTP) cases of TCP connections can |
253 | possibly use the data-on-syn, so support that too. */ | |
fb05276a | 254 | |
10ac8d7f | 255 | if (fastopen_blob && tcp_fastopen_ok) |
fb05276a | 256 | { |
10ac8d7f | 257 | if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len, |
ac0dcd3f | 258 | MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0) |
1ccd5f67 | 259 | /* seen for with-data, experimental TFO option, with-cookie case */ |
8255135b | 260 | /* seen for with-data, proper TFO opt, with-cookie case */ |
ac0dcd3f | 261 | { |
10ac8d7f | 262 | DEBUG(D_transport|D_v) |
ba936fb8 | 263 | debug_printf("non-TFO mode connection attempt to %s, %lu data\n", |
4aa2e44b | 264 | address, (unsigned long)fastopen_blob->len); |
10ac8d7f | 265 | tcp_out_fastopen = fastopen_blob->len > 0 ? 2 : 1; |
ac0dcd3f | 266 | } |
8255135b | 267 | else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */ |
1ccd5f67 JH |
268 | /* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */ |
269 | /* apparently no visibility of the diffference at this point */ | |
8255135b | 270 | /* seen for with-data, proper TFO opt, cookie-req */ |
1ccd5f67 JH |
271 | /* with netwk delay, post-conn tcp_info sees unacked 1 for R, 2 for C; code in smtp_out.c */ |
272 | /* ? older Experimental TFO option behaviour ? */ | |
273 | { /* queue unsent data */ | |
8255135b | 274 | DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n", |
10ac8d7f JH |
275 | fastopen_blob->len > 0 ? "with" : "no"); |
276 | if (!fastopen_blob->data) | |
a2673768 | 277 | { |
8255135b | 278 | tcp_out_fastopen = 1; /* we tried; unknown if useful yet */ |
ac0dcd3f | 279 | rc = 0; |
a2673768 | 280 | } |
8255135b | 281 | else |
10ac8d7f | 282 | rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0); |
ac0dcd3f JH |
283 | } |
284 | else if(errno == EOPNOTSUPP) | |
285 | { | |
286 | DEBUG(D_transport) | |
287 | debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); | |
288 | goto legacy_connect; | |
289 | } | |
fb05276a JH |
290 | } |
291 | else | |
292 | #endif | |
0ab63f3d JH |
293 | { |
294 | legacy_connect: | |
10ac8d7f | 295 | DEBUG(D_transport|D_v) if (fastopen_blob) |
4aa2e44b JH |
296 | debug_printf("non-TFO mode connection attempt to %s, %lu data\n", |
297 | address, (unsigned long)fastopen_blob->len); | |
0ab63f3d | 298 | if ((rc = connect(sock, s_ptr, s_len)) >= 0) |
10ac8d7f JH |
299 | if ( fastopen_blob && fastopen_blob->data && fastopen_blob->len |
300 | && send(sock, fastopen_blob->data, fastopen_blob->len, 0) < 0) | |
0ab63f3d JH |
301 | rc = -1; |
302 | } | |
fb05276a | 303 | |
059ec3d9 PH |
304 | save_errno = errno; |
305 | alarm(0); | |
306 | ||
307 | /* There is a testing facility for simulating a connection timeout, as I | |
308 | can't think of any other way of doing this. It converts a connection refused | |
75e0e026 | 309 | into a timeout if the timeout is set to 999999. */ |
059ec3d9 | 310 | |
a39bd74d | 311 | if (running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999) |
059ec3d9 | 312 | { |
a39bd74d JB |
313 | rc = -1; |
314 | save_errno = EINTR; | |
315 | sigalrm_seen = TRUE; | |
059ec3d9 PH |
316 | } |
317 | ||
318 | /* Success */ | |
319 | ||
055e2cb4 | 320 | if (rc >= 0) |
055e2cb4 | 321 | return 0; |
059ec3d9 PH |
322 | |
323 | /* A failure whose error code is "Interrupted system call" is in fact | |
324 | an externally applied timeout if the signal handler has been run. */ | |
325 | ||
a39bd74d | 326 | errno = save_errno == EINTR && sigalrm_seen ? ETIMEDOUT : save_errno; |
059ec3d9 PH |
327 | return -1; |
328 | } | |
329 | ||
330 | ||
a6d4c44e TF |
331 | |
332 | /************************************************* | |
333 | * Create connected socket to remote host * | |
334 | *************************************************/ | |
335 | ||
b1f8e4f8 JH |
336 | /* Create a socket and connect to host (name or number, ipv6 ok) |
337 | at one of port-range. | |
a6d4c44e | 338 | |
b1f8e4f8 JH |
339 | Arguments: |
340 | type SOCK_DGRAM or SOCK_STREAM | |
341 | af AF_INET6 or AF_INET for the socket type | |
342 | address the remote address, in text form | |
343 | portlo,porthi the remote port range | |
344 | timeout a timeout | |
4a5cbaff | 345 | connhost if not NULL, host_item to be filled in with connection details |
b1f8e4f8 | 346 | errstr pointer for allocated string on error |
10ac8d7f | 347 | fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open. |
4a5cbaff | 348 | Additionally, optional early-data to send |
b1f8e4f8 JH |
349 | |
350 | Return: | |
351 | socket fd, or -1 on failure (having allocated an error string) | |
352 | */ | |
353 | int | |
354 | ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi, | |
10ac8d7f | 355 | int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen_blob) |
b1f8e4f8 JH |
356 | { |
357 | int namelen, port; | |
358 | host_item shost; | |
359 | host_item *h; | |
360 | int af = 0, fd, fd4 = -1, fd6 = -1; | |
361 | ||
362 | shost.next = NULL; | |
363 | shost.address = NULL; | |
364 | shost.port = portlo; | |
365 | shost.mx = -1; | |
366 | ||
367 | namelen = Ustrlen(hostname); | |
368 | ||
369 | /* Anything enclosed in [] must be an IP address. */ | |
370 | ||
371 | if (hostname[0] == '[' && | |
372 | hostname[namelen - 1] == ']') | |
373 | { | |
af483912 | 374 | uschar * host = string_copyn(hostname+1, namelen-2); |
b1f8e4f8 JH |
375 | if (string_is_ip_address(host, NULL) == 0) |
376 | { | |
377 | *errstr = string_sprintf("malformed IP address \"%s\"", hostname); | |
378 | return -1; | |
379 | } | |
380 | shost.name = shost.address = host; | |
381 | } | |
382 | ||
383 | /* Otherwise check for an unadorned IP address */ | |
384 | ||
385 | else if (string_is_ip_address(hostname, NULL) != 0) | |
af483912 | 386 | shost.name = shost.address = string_copyn(hostname, namelen); |
b1f8e4f8 JH |
387 | |
388 | /* Otherwise lookup IP address(es) from the name */ | |
389 | ||
390 | else | |
391 | { | |
af483912 | 392 | shost.name = string_copyn(hostname, namelen); |
1f155f8e JH |
393 | if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE, |
394 | NULL, FALSE) != HOST_FOUND) | |
b1f8e4f8 JH |
395 | { |
396 | *errstr = string_sprintf("no IP address found for host %s", shost.name); | |
397 | return -1; | |
398 | } | |
399 | } | |
400 | ||
401 | /* Try to connect to the server - test each IP till one works */ | |
402 | ||
fb05276a | 403 | for (h = &shost; h; h = h->next) |
b1f8e4f8 | 404 | { |
af483912 JH |
405 | fd = Ustrchr(h->address, ':') != 0 |
406 | ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6 | |
407 | : fd4 < 0 ? (fd4 = ip_socket(type, af = AF_INET )) : fd4; | |
b1f8e4f8 JH |
408 | |
409 | if (fd < 0) | |
410 | { | |
411 | *errstr = string_sprintf("failed to create socket: %s", strerror(errno)); | |
412 | goto bad; | |
413 | } | |
414 | ||
415 | for(port = portlo; port <= porthi; port++) | |
10ac8d7f | 416 | if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0) |
b1f8e4f8 JH |
417 | { |
418 | if (fd != fd6) close(fd6); | |
419 | if (fd != fd4) close(fd4); | |
8a512ed5 JH |
420 | if (connhost) |
421 | { | |
b1f8e4f8 JH |
422 | h->port = port; |
423 | *connhost = *h; | |
424 | connhost->next = NULL; | |
425 | } | |
426 | return fd; | |
427 | } | |
428 | } | |
429 | ||
a9764ac5 JH |
430 | *errstr = string_sprintf("failed to connect to any address for %s: %s", |
431 | hostname, strerror(errno)); | |
b1f8e4f8 JH |
432 | |
433 | bad: | |
434 | close(fd4); close(fd6); return -1; | |
435 | } | |
436 | ||
059ec3d9 | 437 | |
4a5cbaff | 438 | /*XXX TFO? */ |
3e60dd41 JH |
439 | int |
440 | ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo) | |
441 | { | |
a39bd74d JB |
442 | int scan; |
443 | uschar hostname[256]; | |
444 | unsigned int portlow, porthigh; | |
445 | ||
446 | /* extract host and port part */ | |
447 | scan = sscanf(CS hostport, "%255s %u-%u", hostname, &portlow, &porthigh); | |
448 | if (scan != 3) | |
449 | { | |
450 | if (scan != 2) | |
451 | { | |
452 | *errstr = string_sprintf("invalid socket '%s'", hostport); | |
453 | return -1; | |
3e60dd41 | 454 | } |
a39bd74d | 455 | porthigh = portlow; |
3e60dd41 JH |
456 | } |
457 | ||
a39bd74d | 458 | return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh, |
4a5cbaff | 459 | tmo, NULL, errstr, NULL); |
3e60dd41 JH |
460 | } |
461 | ||
462 | int | |
463 | ip_unixsocket(const uschar * path, uschar ** errstr) | |
464 | { | |
a39bd74d JB |
465 | int sock; |
466 | struct sockaddr_un server; | |
3e60dd41 | 467 | |
a39bd74d JB |
468 | if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) |
469 | { | |
470 | *errstr = US"can't open UNIX socket."; | |
471 | return -1; | |
3e60dd41 JH |
472 | } |
473 | ||
af483912 | 474 | callout_address = string_copy(path); |
a39bd74d JB |
475 | server.sun_family = AF_UNIX; |
476 | Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1); | |
477 | server.sun_path[sizeof(server.sun_path)-1] = '\0'; | |
478 | if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0) | |
479 | { | |
480 | int err = errno; | |
481 | (void)close(sock); | |
482 | *errstr = string_sprintf("unable to connect to UNIX socket (%s): %s", | |
483 | path, strerror(err)); | |
484 | return -1; | |
485 | } | |
486 | return sock; | |
3e60dd41 JH |
487 | } |
488 | ||
489 | int | |
490 | ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo) | |
491 | { | |
a39bd74d JB |
492 | return *spec == '/' |
493 | ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo); | |
3e60dd41 JH |
494 | } |
495 | ||
059ec3d9 PH |
496 | /************************************************* |
497 | * Set keepalive on a socket * | |
498 | *************************************************/ | |
499 | ||
500 | /* Can be called for both incoming and outgoing sockets. | |
501 | ||
502 | Arguments: | |
503 | sock the socket | |
504 | address the remote host address, for failure logging | |
505 | torf true for outgoing connection, false for incoming | |
506 | ||
507 | Returns: nothing | |
508 | */ | |
509 | ||
510 | void | |
55414b25 | 511 | ip_keepalive(int sock, const uschar *address, BOOL torf) |
059ec3d9 PH |
512 | { |
513 | int fodder = 1; | |
514 | if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, | |
5903c6ff | 515 | US (&fodder), sizeof(fodder)) != 0) |
059ec3d9 PH |
516 | log_write(0, LOG_MAIN, "setsockopt(SO_KEEPALIVE) on connection %s %s " |
517 | "failed: %s", torf? "to":"from", address, strerror(errno)); | |
518 | } | |
519 | ||
520 | ||
521 | ||
522 | /************************************************* | |
523 | * Receive from a socket with timeout * | |
524 | *************************************************/ | |
525 | ||
4e71661f | 526 | /* |
059ec3d9 | 527 | Arguments: |
4e71661f JH |
528 | fd the file descriptor |
529 | timeout the timeout, seconds | |
530 | Returns: TRUE => ready for i/o | |
531 | FALSE => timed out, or other error | |
059ec3d9 | 532 | */ |
4e71661f JH |
533 | BOOL |
534 | fd_ready(int fd, int timeout) | |
059ec3d9 PH |
535 | { |
536 | fd_set select_inset; | |
19050083 | 537 | time_t start_recv = time(NULL); |
c528cec4 | 538 | int time_left = timeout; |
059ec3d9 PH |
539 | int rc; |
540 | ||
85ff3cf9 | 541 | if (time_left <= 0) |
4e71661f JH |
542 | { |
543 | errno = ETIMEDOUT; | |
544 | return FALSE; | |
545 | } | |
059ec3d9 PH |
546 | /* Wait until the socket is ready */ |
547 | ||
a39bd74d | 548 | do |
059ec3d9 | 549 | { |
f2ed27cf | 550 | struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 }; |
059ec3d9 | 551 | FD_ZERO (&select_inset); |
4e71661f | 552 | FD_SET (fd, &select_inset); |
059ec3d9 | 553 | |
0f0c8159 | 554 | /*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/ |
4e71661f | 555 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv); |
059ec3d9 PH |
556 | |
557 | /* If some interrupt arrived, just retry. We presume this to be rare, | |
558 | but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes | |
559 | select() to exit). | |
560 | ||
561 | Aug 2004: Somebody set up a cron job that ran exiwhat every 2 minutes, making | |
562 | the interrupt not at all rare. Since the timeout is typically more than 2 | |
563 | minutes, the effect was to block the timeout completely. To prevent this | |
c528cec4 HSHR |
564 | happening again, we do an explicit time test and adjust the timeout |
565 | accordingly */ | |
059ec3d9 PH |
566 | |
567 | if (rc < 0 && errno == EINTR) | |
568 | { | |
569 | DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n"); | |
85ff3cf9 | 570 | |
c528cec4 | 571 | /* Watch out, 'continue' jumps to the condition, not to the loops top */ |
85ff3cf9 HSHR |
572 | time_left = timeout - (time(NULL) - start_recv); |
573 | if (time_left > 0) continue; | |
059ec3d9 PH |
574 | } |
575 | ||
059ec3d9 PH |
576 | if (rc <= 0) |
577 | { | |
578 | errno = ETIMEDOUT; | |
4e71661f | 579 | return FALSE; |
059ec3d9 PH |
580 | } |
581 | ||
c528cec4 HSHR |
582 | /* Checking the FD_ISSET is not enough, if we're interrupted, the |
583 | select_inset may still contain the 'input'. */ | |
059ec3d9 | 584 | } |
4bd6107d | 585 | while (rc < 0 || !FD_ISSET(fd, &select_inset)); |
4e71661f JH |
586 | return TRUE; |
587 | } | |
588 | ||
589 | /* The timeout is implemented using select(), and we loop to cover select() | |
590 | getting interrupted, and the possibility of select() returning with a positive | |
591 | result but no ready descriptor. Is this in fact possible? | |
592 | ||
593 | Arguments: | |
594 | sock the socket | |
595 | buffer to read into | |
596 | bufsize the buffer size | |
597 | timeout the timeout | |
598 | ||
599 | Returns: > 0 => that much data read | |
600 | <= 0 on error or EOF; errno set - zero for EOF | |
601 | */ | |
602 | ||
603 | int | |
604 | ip_recv(int sock, uschar *buffer, int buffsize, int timeout) | |
605 | { | |
606 | int rc; | |
607 | ||
608 | if (!fd_ready(sock, timeout)) | |
609 | return -1; | |
059ec3d9 PH |
610 | |
611 | /* The socket is ready, read from it (via TLS if it's active). On EOF (i.e. | |
612 | close down of the connection), set errno to zero; otherwise leave it alone. */ | |
613 | ||
614 | #ifdef SUPPORT_TLS | |
817d9f57 JH |
615 | if (tls_out.active == sock) |
616 | rc = tls_read(FALSE, buffer, buffsize); | |
617 | else if (tls_in.active == sock) | |
618 | rc = tls_read(TRUE, buffer, buffsize); | |
059ec3d9 PH |
619 | else |
620 | #endif | |
621 | rc = recv(sock, buffer, buffsize, 0); | |
622 | ||
623 | if (rc > 0) return rc; | |
624 | if (rc == 0) errno = 0; | |
625 | return -1; | |
626 | } | |
627 | ||
628 | ||
9e4f5962 PP |
629 | |
630 | ||
13363eba PP |
631 | /************************************************* |
632 | * Lookup address family of potential socket * | |
633 | *************************************************/ | |
634 | ||
635 | /* Given a file-descriptor, check to see if it's a socket and, if so, | |
636 | return the address family; detects IPv4 vs IPv6. If not a socket then | |
637 | return -1. | |
638 | ||
639 | The value 0 is typically AF_UNSPEC, which should not be seen on a connected | |
640 | fd. If the return is -1, the errno will be from getsockname(); probably | |
641 | ENOTSOCK or ECONNRESET. | |
642 | ||
643 | Arguments: socket-or-not fd | |
644 | Returns: address family or -1 | |
645 | */ | |
646 | ||
647 | int | |
648 | ip_get_address_family(int fd) | |
649 | { | |
650 | struct sockaddr_storage ss; | |
651 | socklen_t sslen = sizeof(ss); | |
652 | ||
653 | if (getsockname(fd, (struct sockaddr *) &ss, &sslen) < 0) | |
654 | return -1; | |
655 | ||
656 | return (int) ss.ss_family; | |
657 | } | |
658 | ||
659 | ||
660 | ||
661 | ||
9e4f5962 PP |
662 | /************************************************* |
663 | * Lookup DSCP settings for a socket * | |
664 | *************************************************/ | |
665 | ||
666 | struct dscp_name_tableentry { | |
667 | const uschar *name; | |
668 | int value; | |
669 | }; | |
670 | /* Keep both of these tables sorted! */ | |
671 | static struct dscp_name_tableentry dscp_table[] = { | |
672 | #ifdef IPTOS_DSCP_AF11 | |
36a3ae5f PP |
673 | { CUS"af11", IPTOS_DSCP_AF11 }, |
674 | { CUS"af12", IPTOS_DSCP_AF12 }, | |
675 | { CUS"af13", IPTOS_DSCP_AF13 }, | |
676 | { CUS"af21", IPTOS_DSCP_AF21 }, | |
677 | { CUS"af22", IPTOS_DSCP_AF22 }, | |
678 | { CUS"af23", IPTOS_DSCP_AF23 }, | |
679 | { CUS"af31", IPTOS_DSCP_AF31 }, | |
680 | { CUS"af32", IPTOS_DSCP_AF32 }, | |
681 | { CUS"af33", IPTOS_DSCP_AF33 }, | |
682 | { CUS"af41", IPTOS_DSCP_AF41 }, | |
683 | { CUS"af42", IPTOS_DSCP_AF42 }, | |
684 | { CUS"af43", IPTOS_DSCP_AF43 }, | |
685 | { CUS"ef", IPTOS_DSCP_EF }, | |
9e4f5962 PP |
686 | #endif |
687 | #ifdef IPTOS_LOWCOST | |
36a3ae5f | 688 | { CUS"lowcost", IPTOS_LOWCOST }, |
9e4f5962 | 689 | #endif |
36a3ae5f | 690 | { CUS"lowdelay", IPTOS_LOWDELAY }, |
9e4f5962 | 691 | #ifdef IPTOS_MINCOST |
36a3ae5f | 692 | { CUS"mincost", IPTOS_MINCOST }, |
9e4f5962 | 693 | #endif |
36a3ae5f PP |
694 | { CUS"reliability", IPTOS_RELIABILITY }, |
695 | { CUS"throughput", IPTOS_THROUGHPUT } | |
9e4f5962 PP |
696 | }; |
697 | static int dscp_table_size = | |
698 | sizeof(dscp_table) / sizeof(struct dscp_name_tableentry); | |
699 | ||
700 | /* DSCP values change by protocol family, and so do the options used for | |
2a1b36b3 PP |
701 | setsockopt(); this utility does all the lookups. It takes an unexpanded |
702 | option string, expands it, strips off affix whitespace, then checks if it's | |
703 | a number. If all of what's left is a number, then that's how the option will | |
704 | be parsed and success/failure is a range check. If it's not all a number, | |
705 | then it must be a supported keyword. | |
9e4f5962 PP |
706 | |
707 | Arguments: | |
708 | dscp_name a string, so far unvalidated | |
709 | af address_family in use | |
710 | level setsockopt level to use | |
711 | optname setsockopt name to use | |
712 | dscp_value value for dscp_name | |
713 | ||
714 | Returns: TRUE if okay to setsockopt(), else FALSE | |
2a1b36b3 PP |
715 | |
716 | *level and *optname may be set even if FALSE is returned | |
9e4f5962 PP |
717 | */ |
718 | ||
719 | BOOL | |
720 | dscp_lookup(const uschar *dscp_name, int af, | |
721 | int *level, int *optname, int *dscp_value) | |
722 | { | |
2a1b36b3 | 723 | uschar *dscp_lookup, *p; |
9e4f5962 | 724 | int first, last; |
2a1b36b3 | 725 | long rawlong; |
9e4f5962 PP |
726 | |
727 | if (af == AF_INET) | |
728 | { | |
729 | *level = IPPROTO_IP; | |
730 | *optname = IP_TOS; | |
731 | } | |
bb7b9411 | 732 | #if HAVE_IPV6 && defined(IPV6_TCLASS) |
9e4f5962 PP |
733 | else if (af == AF_INET6) |
734 | { | |
735 | *level = IPPROTO_IPV6; | |
736 | *optname = IPV6_TCLASS; | |
737 | } | |
b301a50b | 738 | #endif |
9e4f5962 PP |
739 | else |
740 | { | |
741 | DEBUG(D_transport) | |
742 | debug_printf("Unhandled address family %d in dscp_lookup()\n", af); | |
743 | return FALSE; | |
744 | } | |
745 | if (!dscp_name) | |
746 | { | |
747 | DEBUG(D_transport) | |
748 | debug_printf("[empty DSCP]\n"); | |
749 | return FALSE; | |
750 | } | |
751 | dscp_lookup = expand_string(US dscp_name); | |
752 | if (dscp_lookup == NULL || *dscp_lookup == '\0') | |
753 | return FALSE; | |
754 | ||
2a1b36b3 PP |
755 | p = dscp_lookup + Ustrlen(dscp_lookup) - 1; |
756 | while (isspace(*p)) *p-- = '\0'; | |
757 | while (isspace(*dscp_lookup) && dscp_lookup < p) dscp_lookup++; | |
758 | if (*dscp_lookup == '\0') | |
759 | return FALSE; | |
760 | ||
761 | rawlong = Ustrtol(dscp_lookup, &p, 0); | |
762 | if (p != dscp_lookup && *p == '\0') | |
763 | { | |
764 | /* We have six bits available, which will end up shifted to fit in 0xFC mask. | |
765 | RFC 2597 defines the values unshifted. */ | |
766 | if (rawlong < 0 || rawlong > 0x3F) | |
767 | { | |
768 | DEBUG(D_transport) | |
769 | debug_printf("DSCP value %ld out of range, ignored.\n", rawlong); | |
770 | return FALSE; | |
771 | } | |
772 | *dscp_value = rawlong << 2; | |
773 | return TRUE; | |
774 | } | |
775 | ||
9e4f5962 PP |
776 | first = 0; |
777 | last = dscp_table_size; | |
778 | while (last > first) | |
779 | { | |
780 | int middle = (first + last)/2; | |
781 | int c = Ustrcmp(dscp_lookup, dscp_table[middle].name); | |
782 | if (c == 0) | |
783 | { | |
784 | *dscp_value = dscp_table[middle].value; | |
785 | return TRUE; | |
786 | } | |
787 | else if (c > 0) | |
9e4f5962 | 788 | first = middle + 1; |
9e4f5962 | 789 | else |
9e4f5962 | 790 | last = middle; |
9e4f5962 PP |
791 | } |
792 | return FALSE; | |
793 | } | |
794 | ||
36a3ae5f PP |
795 | void |
796 | dscp_list_to_stream(FILE *stream) | |
797 | { | |
798 | int i; | |
799 | for (i=0; i < dscp_table_size; ++i) | |
800 | fprintf(stream, "%s\n", dscp_table[i].name); | |
801 | } | |
802 | ||
9e4f5962 | 803 | |
059ec3d9 | 804 | /* End of ip.c */ |
8a512ed5 JH |
805 | /* vi: aw ai sw=2 |
806 | */ |