Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
f9ba5e22 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
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 | 175 | ) |
8768d548 | 176 | f.tcp_fastopen_ok = TRUE; |
10ac8d7f JH |
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 | 252 | the SMTP banner. Other (than SMTP) cases of TCP connections can |
9d2ec425 JH |
253 | possibly use the data-on-syn, so support that too. |
254 | ||
255 | This is a Linux implementation. It might be useable on FreeBSD; I have | |
256 | not checked. I think MacOS has a "connectx" call for this purpose, | |
257 | rather than using "sendto" ? */ | |
fb05276a | 258 | |
8768d548 | 259 | if (fastopen_blob && f.tcp_fastopen_ok) |
fb05276a | 260 | { |
10ac8d7f | 261 | if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len, |
ac0dcd3f | 262 | MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0) |
1ccd5f67 | 263 | /* seen for with-data, experimental TFO option, with-cookie case */ |
8255135b | 264 | /* seen for with-data, proper TFO opt, with-cookie case */ |
ac0dcd3f | 265 | { |
10ac8d7f | 266 | DEBUG(D_transport|D_v) |
ba936fb8 | 267 | debug_printf("non-TFO mode connection attempt to %s, %lu data\n", |
4aa2e44b | 268 | address, (unsigned long)fastopen_blob->len); |
afdb5e9c | 269 | /*XXX also seen on successful TFO, sigh */ |
10ac8d7f | 270 | tcp_out_fastopen = fastopen_blob->len > 0 ? 2 : 1; |
ac0dcd3f | 271 | } |
8255135b | 272 | else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */ |
1ccd5f67 JH |
273 | /* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */ |
274 | /* apparently no visibility of the diffference at this point */ | |
8255135b | 275 | /* seen for with-data, proper TFO opt, cookie-req */ |
1ccd5f67 JH |
276 | /* with netwk delay, post-conn tcp_info sees unacked 1 for R, 2 for C; code in smtp_out.c */ |
277 | /* ? older Experimental TFO option behaviour ? */ | |
278 | { /* queue unsent data */ | |
8255135b | 279 | DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n", |
10ac8d7f JH |
280 | fastopen_blob->len > 0 ? "with" : "no"); |
281 | if (!fastopen_blob->data) | |
a2673768 | 282 | { |
8255135b | 283 | tcp_out_fastopen = 1; /* we tried; unknown if useful yet */ |
ac0dcd3f | 284 | rc = 0; |
a2673768 | 285 | } |
8255135b | 286 | else |
10ac8d7f | 287 | rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0); |
ac0dcd3f JH |
288 | } |
289 | else if(errno == EOPNOTSUPP) | |
290 | { | |
291 | DEBUG(D_transport) | |
292 | debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); | |
293 | goto legacy_connect; | |
294 | } | |
fb05276a JH |
295 | } |
296 | else | |
297 | #endif | |
0ab63f3d JH |
298 | { |
299 | legacy_connect: | |
10ac8d7f | 300 | DEBUG(D_transport|D_v) if (fastopen_blob) |
4aa2e44b JH |
301 | debug_printf("non-TFO mode connection attempt to %s, %lu data\n", |
302 | address, (unsigned long)fastopen_blob->len); | |
0ab63f3d | 303 | if ((rc = connect(sock, s_ptr, s_len)) >= 0) |
10ac8d7f JH |
304 | if ( fastopen_blob && fastopen_blob->data && fastopen_blob->len |
305 | && send(sock, fastopen_blob->data, fastopen_blob->len, 0) < 0) | |
0ab63f3d JH |
306 | rc = -1; |
307 | } | |
fb05276a | 308 | |
059ec3d9 PH |
309 | save_errno = errno; |
310 | alarm(0); | |
311 | ||
312 | /* There is a testing facility for simulating a connection timeout, as I | |
313 | can't think of any other way of doing this. It converts a connection refused | |
75e0e026 | 314 | into a timeout if the timeout is set to 999999. */ |
059ec3d9 | 315 | |
8768d548 | 316 | if (f.running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999) |
059ec3d9 | 317 | { |
a39bd74d JB |
318 | rc = -1; |
319 | save_errno = EINTR; | |
320 | sigalrm_seen = TRUE; | |
059ec3d9 PH |
321 | } |
322 | ||
323 | /* Success */ | |
324 | ||
055e2cb4 | 325 | if (rc >= 0) |
055e2cb4 | 326 | return 0; |
059ec3d9 PH |
327 | |
328 | /* A failure whose error code is "Interrupted system call" is in fact | |
329 | an externally applied timeout if the signal handler has been run. */ | |
330 | ||
a39bd74d | 331 | errno = save_errno == EINTR && sigalrm_seen ? ETIMEDOUT : save_errno; |
059ec3d9 PH |
332 | return -1; |
333 | } | |
334 | ||
335 | ||
a6d4c44e TF |
336 | |
337 | /************************************************* | |
338 | * Create connected socket to remote host * | |
339 | *************************************************/ | |
340 | ||
b1f8e4f8 JH |
341 | /* Create a socket and connect to host (name or number, ipv6 ok) |
342 | at one of port-range. | |
a6d4c44e | 343 | |
b1f8e4f8 JH |
344 | Arguments: |
345 | type SOCK_DGRAM or SOCK_STREAM | |
346 | af AF_INET6 or AF_INET for the socket type | |
afdb5e9c | 347 | hostname host name, or ip address (as text) |
b1f8e4f8 JH |
348 | portlo,porthi the remote port range |
349 | timeout a timeout | |
4a5cbaff | 350 | connhost if not NULL, host_item to be filled in with connection details |
b1f8e4f8 | 351 | errstr pointer for allocated string on error |
10ac8d7f | 352 | fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open. |
4a5cbaff | 353 | Additionally, optional early-data to send |
b1f8e4f8 JH |
354 | |
355 | Return: | |
356 | socket fd, or -1 on failure (having allocated an error string) | |
357 | */ | |
358 | int | |
359 | ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi, | |
10ac8d7f | 360 | int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen_blob) |
b1f8e4f8 JH |
361 | { |
362 | int namelen, port; | |
363 | host_item shost; | |
364 | host_item *h; | |
365 | int af = 0, fd, fd4 = -1, fd6 = -1; | |
366 | ||
367 | shost.next = NULL; | |
368 | shost.address = NULL; | |
369 | shost.port = portlo; | |
370 | shost.mx = -1; | |
371 | ||
372 | namelen = Ustrlen(hostname); | |
373 | ||
374 | /* Anything enclosed in [] must be an IP address. */ | |
375 | ||
376 | if (hostname[0] == '[' && | |
377 | hostname[namelen - 1] == ']') | |
378 | { | |
af483912 | 379 | uschar * host = string_copyn(hostname+1, namelen-2); |
b1f8e4f8 JH |
380 | if (string_is_ip_address(host, NULL) == 0) |
381 | { | |
382 | *errstr = string_sprintf("malformed IP address \"%s\"", hostname); | |
383 | return -1; | |
384 | } | |
385 | shost.name = shost.address = host; | |
386 | } | |
387 | ||
388 | /* Otherwise check for an unadorned IP address */ | |
389 | ||
390 | else if (string_is_ip_address(hostname, NULL) != 0) | |
af483912 | 391 | shost.name = shost.address = string_copyn(hostname, namelen); |
b1f8e4f8 JH |
392 | |
393 | /* Otherwise lookup IP address(es) from the name */ | |
394 | ||
395 | else | |
396 | { | |
af483912 | 397 | shost.name = string_copyn(hostname, namelen); |
1f155f8e JH |
398 | if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE, |
399 | NULL, FALSE) != HOST_FOUND) | |
b1f8e4f8 JH |
400 | { |
401 | *errstr = string_sprintf("no IP address found for host %s", shost.name); | |
402 | return -1; | |
403 | } | |
404 | } | |
405 | ||
406 | /* Try to connect to the server - test each IP till one works */ | |
407 | ||
fb05276a | 408 | for (h = &shost; h; h = h->next) |
b1f8e4f8 | 409 | { |
af483912 JH |
410 | fd = Ustrchr(h->address, ':') != 0 |
411 | ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6 | |
412 | : fd4 < 0 ? (fd4 = ip_socket(type, af = AF_INET )) : fd4; | |
b1f8e4f8 JH |
413 | |
414 | if (fd < 0) | |
415 | { | |
416 | *errstr = string_sprintf("failed to create socket: %s", strerror(errno)); | |
417 | goto bad; | |
418 | } | |
419 | ||
420 | for(port = portlo; port <= porthi; port++) | |
10ac8d7f | 421 | if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0) |
b1f8e4f8 JH |
422 | { |
423 | if (fd != fd6) close(fd6); | |
424 | if (fd != fd4) close(fd4); | |
8a512ed5 JH |
425 | if (connhost) |
426 | { | |
b1f8e4f8 JH |
427 | h->port = port; |
428 | *connhost = *h; | |
429 | connhost->next = NULL; | |
430 | } | |
431 | return fd; | |
432 | } | |
433 | } | |
434 | ||
a9764ac5 JH |
435 | *errstr = string_sprintf("failed to connect to any address for %s: %s", |
436 | hostname, strerror(errno)); | |
b1f8e4f8 JH |
437 | |
438 | bad: | |
439 | close(fd4); close(fd6); return -1; | |
440 | } | |
441 | ||
059ec3d9 | 442 | |
4a5cbaff | 443 | /*XXX TFO? */ |
3e60dd41 JH |
444 | int |
445 | ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo) | |
446 | { | |
a39bd74d JB |
447 | int scan; |
448 | uschar hostname[256]; | |
449 | unsigned int portlow, porthigh; | |
450 | ||
451 | /* extract host and port part */ | |
452 | scan = sscanf(CS hostport, "%255s %u-%u", hostname, &portlow, &porthigh); | |
453 | if (scan != 3) | |
454 | { | |
455 | if (scan != 2) | |
456 | { | |
457 | *errstr = string_sprintf("invalid socket '%s'", hostport); | |
458 | return -1; | |
3e60dd41 | 459 | } |
a39bd74d | 460 | porthigh = portlow; |
3e60dd41 JH |
461 | } |
462 | ||
a39bd74d | 463 | return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh, |
4a5cbaff | 464 | tmo, NULL, errstr, NULL); |
3e60dd41 JH |
465 | } |
466 | ||
467 | int | |
468 | ip_unixsocket(const uschar * path, uschar ** errstr) | |
469 | { | |
a39bd74d JB |
470 | int sock; |
471 | struct sockaddr_un server; | |
3e60dd41 | 472 | |
a39bd74d JB |
473 | if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) |
474 | { | |
475 | *errstr = US"can't open UNIX socket."; | |
476 | return -1; | |
3e60dd41 JH |
477 | } |
478 | ||
af483912 | 479 | callout_address = string_copy(path); |
a39bd74d JB |
480 | server.sun_family = AF_UNIX; |
481 | Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1); | |
482 | server.sun_path[sizeof(server.sun_path)-1] = '\0'; | |
483 | if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0) | |
484 | { | |
485 | int err = errno; | |
486 | (void)close(sock); | |
487 | *errstr = string_sprintf("unable to connect to UNIX socket (%s): %s", | |
488 | path, strerror(err)); | |
489 | return -1; | |
490 | } | |
491 | return sock; | |
3e60dd41 JH |
492 | } |
493 | ||
494 | int | |
495 | ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo) | |
496 | { | |
a39bd74d JB |
497 | return *spec == '/' |
498 | ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo); | |
3e60dd41 JH |
499 | } |
500 | ||
059ec3d9 PH |
501 | /************************************************* |
502 | * Set keepalive on a socket * | |
503 | *************************************************/ | |
504 | ||
505 | /* Can be called for both incoming and outgoing sockets. | |
506 | ||
507 | Arguments: | |
508 | sock the socket | |
509 | address the remote host address, for failure logging | |
510 | torf true for outgoing connection, false for incoming | |
511 | ||
512 | Returns: nothing | |
513 | */ | |
514 | ||
515 | void | |
55414b25 | 516 | ip_keepalive(int sock, const uschar *address, BOOL torf) |
059ec3d9 PH |
517 | { |
518 | int fodder = 1; | |
519 | if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, | |
5903c6ff | 520 | US (&fodder), sizeof(fodder)) != 0) |
059ec3d9 PH |
521 | log_write(0, LOG_MAIN, "setsockopt(SO_KEEPALIVE) on connection %s %s " |
522 | "failed: %s", torf? "to":"from", address, strerror(errno)); | |
523 | } | |
524 | ||
525 | ||
526 | ||
527 | /************************************************* | |
528 | * Receive from a socket with timeout * | |
529 | *************************************************/ | |
530 | ||
4e71661f | 531 | /* |
059ec3d9 | 532 | Arguments: |
4e71661f JH |
533 | fd the file descriptor |
534 | timeout the timeout, seconds | |
535 | Returns: TRUE => ready for i/o | |
536 | FALSE => timed out, or other error | |
059ec3d9 | 537 | */ |
4e71661f JH |
538 | BOOL |
539 | fd_ready(int fd, int timeout) | |
059ec3d9 PH |
540 | { |
541 | fd_set select_inset; | |
19050083 | 542 | time_t start_recv = time(NULL); |
c528cec4 | 543 | int time_left = timeout; |
059ec3d9 PH |
544 | int rc; |
545 | ||
85ff3cf9 | 546 | if (time_left <= 0) |
4e71661f JH |
547 | { |
548 | errno = ETIMEDOUT; | |
549 | return FALSE; | |
550 | } | |
059ec3d9 PH |
551 | /* Wait until the socket is ready */ |
552 | ||
a39bd74d | 553 | do |
059ec3d9 | 554 | { |
f2ed27cf | 555 | struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 }; |
059ec3d9 | 556 | FD_ZERO (&select_inset); |
4e71661f | 557 | FD_SET (fd, &select_inset); |
059ec3d9 | 558 | |
0f0c8159 | 559 | /*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/ |
4e71661f | 560 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv); |
059ec3d9 PH |
561 | |
562 | /* If some interrupt arrived, just retry. We presume this to be rare, | |
563 | but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes | |
564 | select() to exit). | |
565 | ||
566 | Aug 2004: Somebody set up a cron job that ran exiwhat every 2 minutes, making | |
567 | the interrupt not at all rare. Since the timeout is typically more than 2 | |
568 | minutes, the effect was to block the timeout completely. To prevent this | |
c528cec4 HSHR |
569 | happening again, we do an explicit time test and adjust the timeout |
570 | accordingly */ | |
059ec3d9 PH |
571 | |
572 | if (rc < 0 && errno == EINTR) | |
573 | { | |
574 | DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n"); | |
85ff3cf9 | 575 | |
c528cec4 | 576 | /* Watch out, 'continue' jumps to the condition, not to the loops top */ |
85ff3cf9 HSHR |
577 | time_left = timeout - (time(NULL) - start_recv); |
578 | if (time_left > 0) continue; | |
059ec3d9 PH |
579 | } |
580 | ||
059ec3d9 PH |
581 | if (rc <= 0) |
582 | { | |
583 | errno = ETIMEDOUT; | |
4e71661f | 584 | return FALSE; |
059ec3d9 PH |
585 | } |
586 | ||
c528cec4 HSHR |
587 | /* Checking the FD_ISSET is not enough, if we're interrupted, the |
588 | select_inset may still contain the 'input'. */ | |
059ec3d9 | 589 | } |
4bd6107d | 590 | while (rc < 0 || !FD_ISSET(fd, &select_inset)); |
4e71661f JH |
591 | return TRUE; |
592 | } | |
593 | ||
594 | /* The timeout is implemented using select(), and we loop to cover select() | |
595 | getting interrupted, and the possibility of select() returning with a positive | |
596 | result but no ready descriptor. Is this in fact possible? | |
597 | ||
598 | Arguments: | |
74f1a423 | 599 | cctx the connection context (socket fd, possibly TLS context) |
4e71661f JH |
600 | buffer to read into |
601 | bufsize the buffer size | |
602 | timeout the timeout | |
603 | ||
604 | Returns: > 0 => that much data read | |
605 | <= 0 on error or EOF; errno set - zero for EOF | |
606 | */ | |
607 | ||
608 | int | |
74f1a423 | 609 | ip_recv(client_conn_ctx * cctx, uschar * buffer, int buffsize, int timeout) |
4e71661f JH |
610 | { |
611 | int rc; | |
612 | ||
74f1a423 | 613 | if (!fd_ready(cctx->sock, timeout)) |
4e71661f | 614 | return -1; |
059ec3d9 PH |
615 | |
616 | /* The socket is ready, read from it (via TLS if it's active). On EOF (i.e. | |
617 | close down of the connection), set errno to zero; otherwise leave it alone. */ | |
618 | ||
619 | #ifdef SUPPORT_TLS | |
74f1a423 JH |
620 | if (cctx->tls_ctx) /* client TLS */ |
621 | rc = tls_read(cctx->tls_ctx, buffer, buffsize); | |
622 | else if (tls_in.active.sock == cctx->sock) /* server TLS */ | |
623 | rc = tls_read(NULL, buffer, buffsize); | |
059ec3d9 PH |
624 | else |
625 | #endif | |
74f1a423 | 626 | rc = recv(cctx->sock, buffer, buffsize, 0); |
059ec3d9 PH |
627 | |
628 | if (rc > 0) return rc; | |
629 | if (rc == 0) errno = 0; | |
630 | return -1; | |
631 | } | |
632 | ||
633 | ||
9e4f5962 PP |
634 | |
635 | ||
13363eba PP |
636 | /************************************************* |
637 | * Lookup address family of potential socket * | |
638 | *************************************************/ | |
639 | ||
640 | /* Given a file-descriptor, check to see if it's a socket and, if so, | |
641 | return the address family; detects IPv4 vs IPv6. If not a socket then | |
642 | return -1. | |
643 | ||
644 | The value 0 is typically AF_UNSPEC, which should not be seen on a connected | |
645 | fd. If the return is -1, the errno will be from getsockname(); probably | |
646 | ENOTSOCK or ECONNRESET. | |
647 | ||
648 | Arguments: socket-or-not fd | |
649 | Returns: address family or -1 | |
650 | */ | |
651 | ||
652 | int | |
653 | ip_get_address_family(int fd) | |
654 | { | |
655 | struct sockaddr_storage ss; | |
656 | socklen_t sslen = sizeof(ss); | |
657 | ||
658 | if (getsockname(fd, (struct sockaddr *) &ss, &sslen) < 0) | |
659 | return -1; | |
660 | ||
661 | return (int) ss.ss_family; | |
662 | } | |
663 | ||
664 | ||
665 | ||
666 | ||
9e4f5962 PP |
667 | /************************************************* |
668 | * Lookup DSCP settings for a socket * | |
669 | *************************************************/ | |
670 | ||
671 | struct dscp_name_tableentry { | |
672 | const uschar *name; | |
673 | int value; | |
674 | }; | |
675 | /* Keep both of these tables sorted! */ | |
676 | static struct dscp_name_tableentry dscp_table[] = { | |
677 | #ifdef IPTOS_DSCP_AF11 | |
36a3ae5f PP |
678 | { CUS"af11", IPTOS_DSCP_AF11 }, |
679 | { CUS"af12", IPTOS_DSCP_AF12 }, | |
680 | { CUS"af13", IPTOS_DSCP_AF13 }, | |
681 | { CUS"af21", IPTOS_DSCP_AF21 }, | |
682 | { CUS"af22", IPTOS_DSCP_AF22 }, | |
683 | { CUS"af23", IPTOS_DSCP_AF23 }, | |
684 | { CUS"af31", IPTOS_DSCP_AF31 }, | |
685 | { CUS"af32", IPTOS_DSCP_AF32 }, | |
686 | { CUS"af33", IPTOS_DSCP_AF33 }, | |
687 | { CUS"af41", IPTOS_DSCP_AF41 }, | |
688 | { CUS"af42", IPTOS_DSCP_AF42 }, | |
689 | { CUS"af43", IPTOS_DSCP_AF43 }, | |
690 | { CUS"ef", IPTOS_DSCP_EF }, | |
9e4f5962 PP |
691 | #endif |
692 | #ifdef IPTOS_LOWCOST | |
36a3ae5f | 693 | { CUS"lowcost", IPTOS_LOWCOST }, |
9e4f5962 | 694 | #endif |
36a3ae5f | 695 | { CUS"lowdelay", IPTOS_LOWDELAY }, |
9e4f5962 | 696 | #ifdef IPTOS_MINCOST |
36a3ae5f | 697 | { CUS"mincost", IPTOS_MINCOST }, |
9e4f5962 | 698 | #endif |
36a3ae5f PP |
699 | { CUS"reliability", IPTOS_RELIABILITY }, |
700 | { CUS"throughput", IPTOS_THROUGHPUT } | |
9e4f5962 PP |
701 | }; |
702 | static int dscp_table_size = | |
703 | sizeof(dscp_table) / sizeof(struct dscp_name_tableentry); | |
704 | ||
705 | /* DSCP values change by protocol family, and so do the options used for | |
2a1b36b3 PP |
706 | setsockopt(); this utility does all the lookups. It takes an unexpanded |
707 | option string, expands it, strips off affix whitespace, then checks if it's | |
708 | a number. If all of what's left is a number, then that's how the option will | |
709 | be parsed and success/failure is a range check. If it's not all a number, | |
710 | then it must be a supported keyword. | |
9e4f5962 PP |
711 | |
712 | Arguments: | |
713 | dscp_name a string, so far unvalidated | |
714 | af address_family in use | |
715 | level setsockopt level to use | |
716 | optname setsockopt name to use | |
717 | dscp_value value for dscp_name | |
718 | ||
719 | Returns: TRUE if okay to setsockopt(), else FALSE | |
2a1b36b3 PP |
720 | |
721 | *level and *optname may be set even if FALSE is returned | |
9e4f5962 PP |
722 | */ |
723 | ||
724 | BOOL | |
725 | dscp_lookup(const uschar *dscp_name, int af, | |
726 | int *level, int *optname, int *dscp_value) | |
727 | { | |
2a1b36b3 | 728 | uschar *dscp_lookup, *p; |
9e4f5962 | 729 | int first, last; |
2a1b36b3 | 730 | long rawlong; |
9e4f5962 PP |
731 | |
732 | if (af == AF_INET) | |
733 | { | |
734 | *level = IPPROTO_IP; | |
735 | *optname = IP_TOS; | |
736 | } | |
bb7b9411 | 737 | #if HAVE_IPV6 && defined(IPV6_TCLASS) |
9e4f5962 PP |
738 | else if (af == AF_INET6) |
739 | { | |
740 | *level = IPPROTO_IPV6; | |
741 | *optname = IPV6_TCLASS; | |
742 | } | |
b301a50b | 743 | #endif |
9e4f5962 PP |
744 | else |
745 | { | |
746 | DEBUG(D_transport) | |
747 | debug_printf("Unhandled address family %d in dscp_lookup()\n", af); | |
748 | return FALSE; | |
749 | } | |
750 | if (!dscp_name) | |
751 | { | |
752 | DEBUG(D_transport) | |
753 | debug_printf("[empty DSCP]\n"); | |
754 | return FALSE; | |
755 | } | |
756 | dscp_lookup = expand_string(US dscp_name); | |
757 | if (dscp_lookup == NULL || *dscp_lookup == '\0') | |
758 | return FALSE; | |
759 | ||
2a1b36b3 PP |
760 | p = dscp_lookup + Ustrlen(dscp_lookup) - 1; |
761 | while (isspace(*p)) *p-- = '\0'; | |
762 | while (isspace(*dscp_lookup) && dscp_lookup < p) dscp_lookup++; | |
763 | if (*dscp_lookup == '\0') | |
764 | return FALSE; | |
765 | ||
766 | rawlong = Ustrtol(dscp_lookup, &p, 0); | |
767 | if (p != dscp_lookup && *p == '\0') | |
768 | { | |
769 | /* We have six bits available, which will end up shifted to fit in 0xFC mask. | |
770 | RFC 2597 defines the values unshifted. */ | |
771 | if (rawlong < 0 || rawlong > 0x3F) | |
772 | { | |
773 | DEBUG(D_transport) | |
774 | debug_printf("DSCP value %ld out of range, ignored.\n", rawlong); | |
775 | return FALSE; | |
776 | } | |
777 | *dscp_value = rawlong << 2; | |
778 | return TRUE; | |
779 | } | |
780 | ||
9e4f5962 PP |
781 | first = 0; |
782 | last = dscp_table_size; | |
783 | while (last > first) | |
784 | { | |
785 | int middle = (first + last)/2; | |
786 | int c = Ustrcmp(dscp_lookup, dscp_table[middle].name); | |
787 | if (c == 0) | |
788 | { | |
789 | *dscp_value = dscp_table[middle].value; | |
790 | return TRUE; | |
791 | } | |
792 | else if (c > 0) | |
9e4f5962 | 793 | first = middle + 1; |
9e4f5962 | 794 | else |
9e4f5962 | 795 | last = middle; |
9e4f5962 PP |
796 | } |
797 | return FALSE; | |
798 | } | |
799 | ||
36a3ae5f PP |
800 | void |
801 | dscp_list_to_stream(FILE *stream) | |
802 | { | |
803 | int i; | |
804 | for (i=0; i < dscp_table_size; ++i) | |
805 | fprintf(stream, "%s\n", dscp_table[i].name); | |
806 | } | |
807 | ||
9e4f5962 | 808 | |
059ec3d9 | 809 | /* End of ip.c */ |
8a512ed5 JH |
810 | /* vi: aw ai sw=2 |
811 | */ |