MacOS: fix build
[exim.git] / src / src / ip.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
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
10 that other parts of Exim can call, especially as there are now several
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
67 ip_addrinfo(const uschar *address, struct sockaddr_in6 *saddr)
68 {
69 #ifdef IPV6_USE_INET_PTON
70
71 if (inet_pton(AF_INET6, CCS address, &saddr->sin6_addr) != 1)
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;
84 if ((rc = getaddrinfo(CCS address, NULL, &hints, &res)) != 0 || res == NULL)
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
100 int
101 ip_addr(void * sin_, int af, const uschar * address, int port)
102 {
103 union sockaddr_46 * sin = sin_;
104 memset(sin, 0, sizeof(*sin));
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 {
114 sin->v6.sin6_family = AF_INET6;
115 sin->v6.sin6_addr = in6addr_any;
116 }
117 else
118 ip_addrinfo(address, &sin->v6); /* Panic-dies on error */
119 sin->v6.sin6_port = htons(port);
120 return sizeof(sin->v6);
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 {
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);
136 }
137 }
138
139
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);
158 return bind(sock, (struct sockaddr *)&sin, s_len);
159 }
160
161
162
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
174 && setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &backlog, sizeof(backlog))
175 )
176 f.tcp_fastopen_ok = TRUE;
177 close(sock);
178 # endif
179 }
180 #endif
181
182
183 /*************************************************
184 * Connect socket to remote host *
185 *************************************************/
186
187 /* This function connects a socket to a remote address and port. The socket may
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.
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
197 timeout a timeout (zero for indefinite timeout)
198 fastopen_blob non-null iff TCP_FASTOPEN can be used; may indicate early-data to
199 be sent in SYN segment. Any such data must be idempotent.
200
201 Returns: 0 on success; -1 on failure, with errno set
202 */
203
204 int
205 ip_connect(int sock, int af, const uschar *address, int port, int timeout,
206 const blob * fastopen_blob)
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);
236 s_in4.sin_addr.s_addr = (S_ADDR_TYPE)inet_addr(CCS address);
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
244 callout_address = string_sprintf("[%s]:%d", address, port);
245 sigalrm_seen = FALSE;
246 if (timeout > 0) ALARM(timeout);
247
248 #ifdef TCP_FASTOPEN
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
252 the SMTP banner. Other (than SMTP) cases of TCP connections can
253 possibly use the data-on-syn, so support that too. */
254
255 if (fastopen_blob && f.tcp_fastopen_ok)
256 {
257 # ifdef MSG_FASTOPEN
258 /* This is a Linux implementation. It might be useable on FreeBSD; I have
259 not checked. */
260
261 if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len,
262 MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0)
263 /* seen for with-data, experimental TFO option, with-cookie case */
264 /* seen for with-data, proper TFO opt, with-cookie case */
265 {
266 DEBUG(D_transport|D_v)
267 debug_printf("TFO mode connection attempt to %s, %lu data\n",
268 address, (unsigned long)fastopen_blob->len);
269 /*XXX also seen on successful TFO, sigh */
270 tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA;
271 }
272 else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */
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 */
275 /* seen for with-data, proper TFO opt, cookie-req */
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 */
279 DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n",
280 fastopen_blob->len > 0 ? "with" : "no");
281 if (!fastopen_blob->data)
282 {
283 tcp_out_fastopen = TFO_ATTEMPTED_NODATA; /* we tried; unknown if useful yet */
284 rc = 0;
285 }
286 else
287 rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
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 }
295 # endif
296 # ifdef EXIM_TFO_CONNECTX
297 /* MacOS */
298 sa_endpoints_t ends = {
299 .sae_srcif = 0, .sae_srcaddr = NULL, .sae_srcaddrlen = 0,
300 .sae_dstaddr = s_ptr, .sae_dstaddrlen = s_len };
301 struct iovec iov = {
302 .iov_base = fastopen_blob->data, .iov_len = fastopen_blob->len };
303 size_t len;
304
305 if ((rc = connectx(sock, &ends, SAE_ASSOCID_ANY,
306 CONNECT_DATA_IDEMPOTENT, &iov, 1, &len, NULL)) == 0)
307 {
308 DEBUG(D_transport|D_v)
309 debug_printf("TFO mode connection attempt to %s, %lu data\n",
310 address, (unsigned long)fastopen_blob->len);
311 tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA;
312
313 if (len != fastopen_blob->len)
314 DEBUG(D_transport|D_v)
315 debug_printf(" only queued %lu data!\n", (unsigned long)len);
316 }
317 else if (errno == EINPROGRESS)
318 {
319 DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n",
320 fastopen_blob->len > 0 ? "with" : "no");
321 if (!fastopen_blob->data)
322 {
323 tcp_out_fastopen = TFO_ATTEMPTED; /* we tried; unknown if useful yet */
324 rc = 0;
325 }
326 else /* assume that no data was queued; block in send */
327 rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
328 }
329 # endif
330 }
331 else
332 #endif /*TCP_FASTOPEN*/
333 {
334 legacy_connect:
335 DEBUG(D_transport|D_v) if (fastopen_blob)
336 debug_printf("non-TFO mode connection attempt to %s, %lu data\n",
337 address, (unsigned long)fastopen_blob->len);
338 if ((rc = connect(sock, s_ptr, s_len)) >= 0)
339 if ( fastopen_blob && fastopen_blob->data && fastopen_blob->len
340 && send(sock, fastopen_blob->data, fastopen_blob->len, 0) < 0)
341 rc = -1;
342 }
343
344 save_errno = errno;
345 ALARM_CLR(0);
346
347 /* There is a testing facility for simulating a connection timeout, as I
348 can't think of any other way of doing this. It converts a connection refused
349 into a timeout if the timeout is set to 999999. */
350
351 if (f.running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999)
352 {
353 rc = -1;
354 save_errno = EINTR;
355 sigalrm_seen = TRUE;
356 }
357
358 /* Success */
359
360 if (rc >= 0)
361 return 0;
362
363 /* A failure whose error code is "Interrupted system call" is in fact
364 an externally applied timeout if the signal handler has been run. */
365
366 errno = save_errno == EINTR && sigalrm_seen ? ETIMEDOUT : save_errno;
367 return -1;
368 }
369
370
371
372 /*************************************************
373 * Create connected socket to remote host *
374 *************************************************/
375
376 /* Create a socket and connect to host (name or number, ipv6 ok)
377 at one of port-range.
378
379 Arguments:
380 type SOCK_DGRAM or SOCK_STREAM
381 af AF_INET6 or AF_INET for the socket type
382 hostname host name, or ip address (as text)
383 portlo,porthi the remote port range
384 timeout a timeout
385 connhost if not NULL, host_item to be filled in with connection details
386 errstr pointer for allocated string on error
387 fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open.
388 Additionally, optional idempotent early-data to send
389
390 Return:
391 socket fd, or -1 on failure (having allocated an error string)
392 */
393 int
394 ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi,
395 int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen_blob)
396 {
397 int namelen, port;
398 host_item shost;
399 host_item *h;
400 int af = 0, fd, fd4 = -1, fd6 = -1;
401
402 shost.next = NULL;
403 shost.address = NULL;
404 shost.port = portlo;
405 shost.mx = -1;
406
407 namelen = Ustrlen(hostname);
408
409 /* Anything enclosed in [] must be an IP address. */
410
411 if (hostname[0] == '[' &&
412 hostname[namelen - 1] == ']')
413 {
414 uschar * host = string_copyn(hostname+1, namelen-2);
415 if (string_is_ip_address(host, NULL) == 0)
416 {
417 *errstr = string_sprintf("malformed IP address \"%s\"", hostname);
418 return -1;
419 }
420 shost.name = shost.address = host;
421 }
422
423 /* Otherwise check for an unadorned IP address */
424
425 else if (string_is_ip_address(hostname, NULL) != 0)
426 shost.name = shost.address = string_copyn(hostname, namelen);
427
428 /* Otherwise lookup IP address(es) from the name */
429
430 else
431 {
432 shost.name = string_copyn(hostname, namelen);
433 if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE,
434 NULL, FALSE) != HOST_FOUND)
435 {
436 *errstr = string_sprintf("no IP address found for host %s", shost.name);
437 return -1;
438 }
439 }
440
441 /* Try to connect to the server - test each IP till one works */
442
443 for (h = &shost; h; h = h->next)
444 {
445 fd = Ustrchr(h->address, ':') != 0
446 ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6
447 : fd4 < 0 ? (fd4 = ip_socket(type, af = AF_INET )) : fd4;
448
449 if (fd < 0)
450 {
451 *errstr = string_sprintf("failed to create socket: %s", strerror(errno));
452 goto bad;
453 }
454
455 for(port = portlo; port <= porthi; port++)
456 if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0)
457 {
458 if (fd != fd6) close(fd6);
459 if (fd != fd4) close(fd4);
460 if (connhost)
461 {
462 h->port = port;
463 *connhost = *h;
464 connhost->next = NULL;
465 }
466 return fd;
467 }
468 }
469
470 *errstr = string_sprintf("failed to connect to any address for %s: %s",
471 hostname, strerror(errno));
472
473 bad:
474 close(fd4); close(fd6); return -1;
475 }
476
477
478 /*XXX TFO? */
479 int
480 ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo)
481 {
482 int scan;
483 uschar hostname[256];
484 unsigned int portlow, porthigh;
485
486 /* extract host and port part */
487 scan = sscanf(CS hostport, "%255s %u-%u", hostname, &portlow, &porthigh);
488 if (scan != 3)
489 {
490 if (scan != 2)
491 {
492 *errstr = string_sprintf("invalid socket '%s'", hostport);
493 return -1;
494 }
495 porthigh = portlow;
496 }
497
498 return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh,
499 tmo, NULL, errstr, NULL);
500 }
501
502 int
503 ip_unixsocket(const uschar * path, uschar ** errstr)
504 {
505 int sock;
506 struct sockaddr_un server;
507
508 if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
509 {
510 *errstr = US"can't open UNIX socket.";
511 return -1;
512 }
513
514 callout_address = string_copy(path);
515 server.sun_family = AF_UNIX;
516 Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1);
517 server.sun_path[sizeof(server.sun_path)-1] = '\0';
518 if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0)
519 {
520 int err = errno;
521 (void)close(sock);
522 *errstr = string_sprintf("unable to connect to UNIX socket (%s): %s",
523 path, strerror(err));
524 return -1;
525 }
526 return sock;
527 }
528
529 int
530 ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo)
531 {
532 return *spec == '/'
533 ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo);
534 }
535
536 /*************************************************
537 * Set keepalive on a socket *
538 *************************************************/
539
540 /* Can be called for both incoming and outgoing sockets.
541
542 Arguments:
543 sock the socket
544 address the remote host address, for failure logging
545 torf true for outgoing connection, false for incoming
546
547 Returns: nothing
548 */
549
550 void
551 ip_keepalive(int sock, const uschar *address, BOOL torf)
552 {
553 int fodder = 1;
554 if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
555 US (&fodder), sizeof(fodder)) != 0)
556 log_write(0, LOG_MAIN, "setsockopt(SO_KEEPALIVE) on connection %s %s "
557 "failed: %s", torf? "to":"from", address, strerror(errno));
558 }
559
560
561
562 /*************************************************
563 * Receive from a socket with timeout *
564 *************************************************/
565
566 /*
567 Arguments:
568 fd the file descriptor
569 timeout the timeout, seconds
570 Returns: TRUE => ready for i/o
571 FALSE => timed out, or other error
572 */
573 BOOL
574 fd_ready(int fd, int timeout)
575 {
576 fd_set select_inset;
577 time_t start_recv = time(NULL);
578 int time_left = timeout;
579 int rc;
580
581 if (time_left <= 0)
582 {
583 errno = ETIMEDOUT;
584 return FALSE;
585 }
586 /* Wait until the socket is ready */
587
588 do
589 {
590 struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 };
591 FD_ZERO (&select_inset);
592 FD_SET (fd, &select_inset);
593
594 /*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/
595 rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv);
596
597 /* If some interrupt arrived, just retry. We presume this to be rare,
598 but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes
599 select() to exit).
600
601 Aug 2004: Somebody set up a cron job that ran exiwhat every 2 minutes, making
602 the interrupt not at all rare. Since the timeout is typically more than 2
603 minutes, the effect was to block the timeout completely. To prevent this
604 happening again, we do an explicit time test and adjust the timeout
605 accordingly */
606
607 if (rc < 0 && errno == EINTR)
608 {
609 DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n");
610
611 /* Watch out, 'continue' jumps to the condition, not to the loops top */
612 time_left = timeout - (time(NULL) - start_recv);
613 if (time_left > 0) continue;
614 }
615
616 if (rc <= 0)
617 {
618 errno = ETIMEDOUT;
619 return FALSE;
620 }
621
622 /* Checking the FD_ISSET is not enough, if we're interrupted, the
623 select_inset may still contain the 'input'. */
624 }
625 while (rc < 0 || !FD_ISSET(fd, &select_inset));
626 return TRUE;
627 }
628
629 /* The timeout is implemented using select(), and we loop to cover select()
630 getting interrupted, and the possibility of select() returning with a positive
631 result but no ready descriptor. Is this in fact possible?
632
633 Arguments:
634 cctx the connection context (socket fd, possibly TLS context)
635 buffer to read into
636 bufsize the buffer size
637 timeout the timeout
638
639 Returns: > 0 => that much data read
640 <= 0 on error or EOF; errno set - zero for EOF
641 */
642
643 int
644 ip_recv(client_conn_ctx * cctx, uschar * buffer, int buffsize, int timeout)
645 {
646 int rc;
647
648 if (!fd_ready(cctx->sock, timeout))
649 return -1;
650
651 /* The socket is ready, read from it (via TLS if it's active). On EOF (i.e.
652 close down of the connection), set errno to zero; otherwise leave it alone. */
653
654 #ifdef SUPPORT_TLS
655 if (cctx->tls_ctx) /* client TLS */
656 rc = tls_read(cctx->tls_ctx, buffer, buffsize);
657 else if (tls_in.active.sock == cctx->sock) /* server TLS */
658 rc = tls_read(NULL, buffer, buffsize);
659 else
660 #endif
661 rc = recv(cctx->sock, buffer, buffsize, 0);
662
663 if (rc > 0) return rc;
664 if (rc == 0) errno = 0;
665 return -1;
666 }
667
668
669
670
671 /*************************************************
672 * Lookup address family of potential socket *
673 *************************************************/
674
675 /* Given a file-descriptor, check to see if it's a socket and, if so,
676 return the address family; detects IPv4 vs IPv6. If not a socket then
677 return -1.
678
679 The value 0 is typically AF_UNSPEC, which should not be seen on a connected
680 fd. If the return is -1, the errno will be from getsockname(); probably
681 ENOTSOCK or ECONNRESET.
682
683 Arguments: socket-or-not fd
684 Returns: address family or -1
685 */
686
687 int
688 ip_get_address_family(int fd)
689 {
690 struct sockaddr_storage ss;
691 socklen_t sslen = sizeof(ss);
692
693 if (getsockname(fd, (struct sockaddr *) &ss, &sslen) < 0)
694 return -1;
695
696 return (int) ss.ss_family;
697 }
698
699
700
701
702 /*************************************************
703 * Lookup DSCP settings for a socket *
704 *************************************************/
705
706 struct dscp_name_tableentry {
707 const uschar *name;
708 int value;
709 };
710 /* Keep both of these tables sorted! */
711 static struct dscp_name_tableentry dscp_table[] = {
712 #ifdef IPTOS_DSCP_AF11
713 { CUS"af11", IPTOS_DSCP_AF11 },
714 { CUS"af12", IPTOS_DSCP_AF12 },
715 { CUS"af13", IPTOS_DSCP_AF13 },
716 { CUS"af21", IPTOS_DSCP_AF21 },
717 { CUS"af22", IPTOS_DSCP_AF22 },
718 { CUS"af23", IPTOS_DSCP_AF23 },
719 { CUS"af31", IPTOS_DSCP_AF31 },
720 { CUS"af32", IPTOS_DSCP_AF32 },
721 { CUS"af33", IPTOS_DSCP_AF33 },
722 { CUS"af41", IPTOS_DSCP_AF41 },
723 { CUS"af42", IPTOS_DSCP_AF42 },
724 { CUS"af43", IPTOS_DSCP_AF43 },
725 { CUS"ef", IPTOS_DSCP_EF },
726 #endif
727 #ifdef IPTOS_LOWCOST
728 { CUS"lowcost", IPTOS_LOWCOST },
729 #endif
730 { CUS"lowdelay", IPTOS_LOWDELAY },
731 #ifdef IPTOS_MINCOST
732 { CUS"mincost", IPTOS_MINCOST },
733 #endif
734 { CUS"reliability", IPTOS_RELIABILITY },
735 { CUS"throughput", IPTOS_THROUGHPUT }
736 };
737 static int dscp_table_size =
738 sizeof(dscp_table) / sizeof(struct dscp_name_tableentry);
739
740 /* DSCP values change by protocol family, and so do the options used for
741 setsockopt(); this utility does all the lookups. It takes an unexpanded
742 option string, expands it, strips off affix whitespace, then checks if it's
743 a number. If all of what's left is a number, then that's how the option will
744 be parsed and success/failure is a range check. If it's not all a number,
745 then it must be a supported keyword.
746
747 Arguments:
748 dscp_name a string, so far unvalidated
749 af address_family in use
750 level setsockopt level to use
751 optname setsockopt name to use
752 dscp_value value for dscp_name
753
754 Returns: TRUE if okay to setsockopt(), else FALSE
755
756 *level and *optname may be set even if FALSE is returned
757 */
758
759 BOOL
760 dscp_lookup(const uschar *dscp_name, int af,
761 int *level, int *optname, int *dscp_value)
762 {
763 uschar *dscp_lookup, *p;
764 int first, last;
765 long rawlong;
766
767 if (af == AF_INET)
768 {
769 *level = IPPROTO_IP;
770 *optname = IP_TOS;
771 }
772 #if HAVE_IPV6 && defined(IPV6_TCLASS)
773 else if (af == AF_INET6)
774 {
775 *level = IPPROTO_IPV6;
776 *optname = IPV6_TCLASS;
777 }
778 #endif
779 else
780 {
781 DEBUG(D_transport)
782 debug_printf("Unhandled address family %d in dscp_lookup()\n", af);
783 return FALSE;
784 }
785 if (!dscp_name)
786 {
787 DEBUG(D_transport)
788 debug_printf("[empty DSCP]\n");
789 return FALSE;
790 }
791 dscp_lookup = expand_string(US dscp_name);
792 if (dscp_lookup == NULL || *dscp_lookup == '\0')
793 return FALSE;
794
795 p = dscp_lookup + Ustrlen(dscp_lookup) - 1;
796 while (isspace(*p)) *p-- = '\0';
797 while (isspace(*dscp_lookup) && dscp_lookup < p) dscp_lookup++;
798 if (*dscp_lookup == '\0')
799 return FALSE;
800
801 rawlong = Ustrtol(dscp_lookup, &p, 0);
802 if (p != dscp_lookup && *p == '\0')
803 {
804 /* We have six bits available, which will end up shifted to fit in 0xFC mask.
805 RFC 2597 defines the values unshifted. */
806 if (rawlong < 0 || rawlong > 0x3F)
807 {
808 DEBUG(D_transport)
809 debug_printf("DSCP value %ld out of range, ignored.\n", rawlong);
810 return FALSE;
811 }
812 *dscp_value = rawlong << 2;
813 return TRUE;
814 }
815
816 first = 0;
817 last = dscp_table_size;
818 while (last > first)
819 {
820 int middle = (first + last)/2;
821 int c = Ustrcmp(dscp_lookup, dscp_table[middle].name);
822 if (c == 0)
823 {
824 *dscp_value = dscp_table[middle].value;
825 return TRUE;
826 }
827 else if (c > 0)
828 first = middle + 1;
829 else
830 last = middle;
831 }
832 return FALSE;
833 }
834
835 void
836 dscp_list_to_stream(FILE *stream)
837 {
838 int i;
839 for (i=0; i < dscp_table_size; ++i)
840 fprintf(stream, "%s\n", dscp_table[i].name);
841 }
842
843
844 /* End of ip.c */
845 /* vi: aw ai sw=2
846 */