Merge from vendor branch SENDMAIL:
[dragonfly.git] / usr.sbin / inetd / builtins.c
CommitLineData
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1/*-
2 * Copyright (c) 1983, 1991, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: src/usr.sbin/inetd/builtins.c,v 1.19.2.7 2002/07/22 14:05:56 fanf Exp $
71126e33 27 * $DragonFly: src/usr.sbin/inetd/builtins.c,v 1.5 2004/12/18 22:48:03 swildner Exp $
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28 *
29 */
30
31#include <sys/filio.h>
32#include <sys/ioccom.h>
33#include <sys/param.h>
34#include <sys/stat.h>
35#include <sys/socket.h>
36#include <sys/sysctl.h>
37#include <sys/ucred.h>
38#include <sys/uio.h>
39#include <sys/utsname.h>
40
41#include <ctype.h>
42#include <err.h>
43#include <errno.h>
44#include <fcntl.h>
45#include <limits.h>
46#include <pwd.h>
47#include <signal.h>
48#include <stdlib.h>
49#include <string.h>
50#include <sysexits.h>
51#include <syslog.h>
52#include <unistd.h>
53
54#include "inetd.h"
55
2d8a3be7
EN
56void chargen_dg(int, struct servtab *);
57void chargen_stream(int, struct servtab *);
58void daytime_dg(int, struct servtab *);
59void daytime_stream(int, struct servtab *);
60void discard_dg(int, struct servtab *);
61void discard_stream(int, struct servtab *);
62void echo_dg(int, struct servtab *);
63void echo_stream(int, struct servtab *);
64static int getline(int, char *, int);
65void iderror(int, int, int, const char *);
66void ident_stream(int, struct servtab *);
67void initring(void);
68unsigned long machtime(void);
69void machtime_dg(int, struct servtab *);
70void machtime_stream(int, struct servtab *);
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71
72char ring[128];
73char *endring;
74
75
76struct biltin biltins[] = {
77 /* Echo received data */
78 { "echo", SOCK_STREAM, 1, -1, echo_stream },
79 { "echo", SOCK_DGRAM, 0, 1, echo_dg },
80
81 /* Internet /dev/null */
82 { "discard", SOCK_STREAM, 1, -1, discard_stream },
83 { "discard", SOCK_DGRAM, 0, 1, discard_dg },
84
85 /* Return 32 bit time since 1900 */
86 { "time", SOCK_STREAM, 0, -1, machtime_stream },
87 { "time", SOCK_DGRAM, 0, 1, machtime_dg },
88
89 /* Return human-readable time */
90 { "daytime", SOCK_STREAM, 0, -1, daytime_stream },
91 { "daytime", SOCK_DGRAM, 0, 1, daytime_dg },
92
93 /* Familiar character generator */
94 { "chargen", SOCK_STREAM, 1, -1, chargen_stream },
95 { "chargen", SOCK_DGRAM, 0, 1, chargen_dg },
96
97 { "tcpmux", SOCK_STREAM, 1, -1, (bi_fn_t *)tcpmux },
98
99 { "auth", SOCK_STREAM, 1, -1, ident_stream },
100
101 { NULL, 0, 0, 0, NULL }
102};
103
104/*
105 * RFC864 Character Generator Protocol. Generates character data without
106 * any regard for input.
107 */
108
109void
68da13b1 110initring(void)
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111{
112 int i;
113
114 endring = ring;
115
116 for (i = 0; i <= 128; ++i)
117 if (isprint(i))
118 *endring++ = i;
119}
120
121/* ARGSUSED */
122void
68da13b1 123chargen_dg(int s, struct servtab *sep) /* Character generator */
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124{
125 struct sockaddr_storage ss;
126 static char *rs;
127 int len;
128 socklen_t size;
129 char text[LINESIZ+2];
130
131 if (endring == 0) {
132 initring();
133 rs = ring;
134 }
135
136 size = sizeof(ss);
137 if (recvfrom(s, text, sizeof(text), 0,
138 (struct sockaddr *)&ss, &size) < 0)
139 return;
140
141 if (check_loop((struct sockaddr *)&ss, sep))
142 return;
143
144 if ((len = endring - rs) >= LINESIZ)
145 memmove(text, rs, LINESIZ);
146 else {
147 memmove(text, rs, len);
148 memmove(text + len, ring, LINESIZ - len);
149 }
150 if (++rs == endring)
151 rs = ring;
152 text[LINESIZ] = '\r';
153 text[LINESIZ + 1] = '\n';
71126e33 154 sendto(s, text, sizeof(text), 0, (struct sockaddr *)&ss, size);
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155}
156
157/* ARGSUSED */
158void
68da13b1 159chargen_stream(int s, struct servtab *sep) /* Character generator */
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160{
161 int len;
162 char *rs, text[LINESIZ+2];
163
164 inetd_setproctitle(sep->se_service, s);
165
166 if (!endring) {
167 initring();
168 rs = ring;
169 }
170
171 text[LINESIZ] = '\r';
172 text[LINESIZ + 1] = '\n';
173 for (rs = ring;;) {
174 if ((len = endring - rs) >= LINESIZ)
175 memmove(text, rs, LINESIZ);
176 else {
177 memmove(text, rs, len);
178 memmove(text + len, ring, LINESIZ - len);
179 }
180 if (++rs == endring)
181 rs = ring;
182 if (write(s, text, sizeof(text)) != sizeof(text))
183 break;
184 }
185 exit(0);
186}
187
188/*
189 * RFC867 Daytime Protocol. Sends the current date and time as an ascii
190 * character string without any regard for input.
191 */
192
193/* ARGSUSED */
194void
68da13b1 195daytime_dg(int s, struct servtab *sep) /* Return human-readable time of day */
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196{
197 char buffer[256];
198 time_t now;
199 struct sockaddr_storage ss;
200 socklen_t size;
201
202 now = time((time_t *) 0);
203
204 size = sizeof(ss);
205 if (recvfrom(s, buffer, sizeof(buffer), 0,
206 (struct sockaddr *)&ss, &size) < 0)
207 return;
208
209 if (check_loop((struct sockaddr *)&ss, sep))
210 return;
211
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212 sprintf(buffer, "%.24s\r\n", ctime(&now));
213 sendto(s, buffer, strlen(buffer), 0, (struct sockaddr *)&ss, size);
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214}
215
216/* ARGSUSED */
217void
68da13b1 218daytime_stream(int s, struct servtab *sep __unused) /* Return human-readable time of day */
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219{
220 char buffer[256];
221 time_t now;
222
223 now = time((time_t *) 0);
224
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225 sprintf(buffer, "%.24s\r\n", ctime(&now));
226 send(s, buffer, strlen(buffer), MSG_EOF);
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227}
228
229/*
230 * RFC863 Discard Protocol. Any data received is thrown away and no response
231 * is sent.
232 */
233
234/* ARGSUSED */
235void
68da13b1 236discard_dg(int s, struct servtab *sep __unused) /* Discard service -- ignore data */
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237{
238 char buffer[BUFSIZE];
239
71126e33 240 read(s, buffer, sizeof(buffer));
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241}
242
243/* ARGSUSED */
244void
68da13b1 245discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */
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246{
247 int ret;
248 char buffer[BUFSIZE];
249
250 inetd_setproctitle(sep->se_service, s);
251 while (1) {
252 while ((ret = read(s, buffer, sizeof(buffer))) > 0)
253 ;
254 if (ret == 0 || errno != EINTR)
255 break;
256 }
257 exit(0);
258}
259
260/*
261 * RFC862 Echo Protocol. Any data received is sent back to the sender as
262 * received.
263 */
264
265/* ARGSUSED */
266void
68da13b1 267echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */
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268{
269 char buffer[65536]; /* Should be sizeof(max datagram). */
270 int i;
271 socklen_t size;
272 struct sockaddr_storage ss;
273
274 size = sizeof(ss);
275 if ((i = recvfrom(s, buffer, sizeof(buffer), 0,
276 (struct sockaddr *)&ss, &size)) < 0)
277 return;
278
279 if (check_loop((struct sockaddr *)&ss, sep))
280 return;
281
71126e33 282 sendto(s, buffer, i, 0, (struct sockaddr *)&ss, size);
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283}
284
285/* ARGSUSED */
286void
68da13b1 287echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */
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288{
289 char buffer[BUFSIZE];
290 int i;
291
292 inetd_setproctitle(sep->se_service, s);
293 while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
294 write(s, buffer, i) > 0)
295 ;
296 exit(0);
297}
298
299/*
300 * RFC1413 Identification Protocol. Given a TCP port number pair, return a
301 * character string which identifies the owner of that connection on the
302 * server's system. Extended to allow for ~/.fakeid support and ~/.noident
303 * support.
304 */
305
306/* RFC 1413 says the following are the only errors you can return. */
307#define ID_INVALID "INVALID-PORT" /* Port number improperly specified. */
308#define ID_NOUSER "NO-USER" /* Port not in use/not identifable. */
309#define ID_HIDDEN "HIDDEN-USER" /* Hiden at user's request. */
310#define ID_UNKNOWN "UNKNOWN-ERROR" /* Everything else. */
311
312/* ARGSUSED */
313void
68da13b1 314iderror(int lport, int fport, int s, const char *er) /* Generic ident_stream error-sending func */
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315{
316 char *p;
317
318 asprintf(&p, "%d , %d : ERROR : %s\r\n", lport, fport, er);
319 if (p == NULL) {
320 syslog(LOG_ERR, "asprintf: %m");
321 exit(EX_OSERR);
322 }
323 send(s, p, strlen(p), MSG_EOF);
324 free(p);
325
326 exit(0);
327}
328
329/* ARGSUSED */
330void
68da13b1 331ident_stream(int s, struct servtab *sep) /* Ident service (AKA "auth") */
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332{
333 struct utsname un;
334 struct stat sb;
335 struct sockaddr_in sin4[2];
336#ifdef INET6
337 struct sockaddr_in6 sin6[2];
338#endif
339 struct sockaddr_storage ss[2];
340 struct ucred uc;
341 struct timeval tv = {
342 10,
343 0
344 }, to;
345 struct passwd *pw = NULL;
346 fd_set fdset;
347 char buf[BUFSIZE], *p, **av, *osname = NULL, e;
348 char idbuf[MAXLOGNAME] = ""; /* Big enough to hold uid in decimal. */
349 socklen_t socklen;
350 ssize_t ssize;
351 size_t size, bufsiz;
352 int c, fflag = 0, nflag = 0, rflag = 0, argc = 0;
353 int gflag = 0, iflag = 0, Fflag = 0, getcredfail = 0, onreadlen;
354 u_short lport, fport;
355
356 inetd_setproctitle(sep->se_service, s);
357 /*
358 * Reset getopt() since we are a fork() but not an exec() from
359 * a parent which used getopt() already.
360 */
361 optind = 1;
362 optreset = 1;
363 /*
364 * Take the internal argument vector and count it out to make an
365 * argument count for getopt. This can be used for any internal
366 * service to read arguments and use getopt() easily.
367 */
368 for (av = sep->se_argv; *av; av++)
369 argc++;
370 if (argc) {
371 int sec, usec;
372 size_t i;
373 u_int32_t rnd32;
374
375 while ((c = getopt(argc, sep->se_argv, "d:fFgino:rt:")) != -1)
376 switch (c) {
377 case 'd':
378 if (!gflag)
379 strlcpy(idbuf, optarg, sizeof(idbuf));
380 break;
381 case 'f':
382 fflag = 1;
383 break;
384 case 'F':
385 fflag = 1;
386 Fflag=1;
387 break;
388 case 'g':
389 gflag = 1;
390 rnd32 = 0; /* Shush, compiler. */
391 /*
392 * The number of bits in "rnd32" divided
393 * by the number of bits needed per iteration
394 * gives a more optimal way to reload the
395 * random number only when necessary.
396 *
397 * 32 bits from arc4random corresponds to
398 * about 6 base-36 digits, so we reseed evey 6.
399 */
400 for (i = 0; i < sizeof(idbuf) - 1; i++) {
401 static const char *const base36 =
402 "0123456789"
403 "abcdefghijklmnopqrstuvwxyz";
404 if (i % 6 == 0)
405 rnd32 = arc4random();
406 idbuf[i] = base36[rnd32 % 36];
407 rnd32 /= 36;
408 }
409 idbuf[i] = '\0';
410 break;
411 case 'i':
412 iflag = 1;
413 break;
414 case 'n':
415 nflag = 1;
416 break;
417 case 'o':
418 osname = optarg;
419 break;
420 case 'r':
421 rflag = 1;
422 break;
423 case 't':
424 switch (sscanf(optarg, "%d.%d", &sec, &usec)) {
425 case 2:
426 tv.tv_usec = usec;
427 /* FALLTHROUGH */
428 case 1:
429 tv.tv_sec = sec;
430 break;
431 default:
432 if (debug)
433 warnx("bad -t argument");
434 break;
435 }
436 break;
437 default:
438 break;
439 }
440 }
441 if (osname == NULL) {
442 if (uname(&un) == -1)
443 iderror(0, 0, s, ID_UNKNOWN);
444 osname = un.sysname;
445 }
446
447 /*
448 * We're going to prepare for and execute reception of a
449 * packet of data from the user. The data is in the format
450 * "local_port , foreign_port\r\n" (with local being the
451 * server's port and foreign being the client's.)
452 */
453 gettimeofday(&to, NULL);
454 to.tv_sec += tv.tv_sec;
455 to.tv_usec += tv.tv_usec;
456 if (to.tv_usec >= 1000000) {
457 to.tv_usec -= 1000000;
458 to.tv_sec++;
459 }
460
461 size = 0;
462 bufsiz = sizeof(buf) - 1;
463 FD_ZERO(&fdset);
464 while (bufsiz > 0) {
465 gettimeofday(&tv, NULL);
466 tv.tv_sec = to.tv_sec - tv.tv_sec;
467 tv.tv_usec = to.tv_usec - tv.tv_usec;
468 if (tv.tv_usec < 0) {
469 tv.tv_usec += 1000000;
470 tv.tv_sec--;
471 }
472 if (tv.tv_sec < 0)
473 break;
474 FD_SET(s, &fdset);
475 if (select(s + 1, &fdset, NULL, NULL, &tv) == -1)
476 iderror(0, 0, s, ID_UNKNOWN);
477 if (ioctl(s, FIONREAD, &onreadlen) == -1)
478 iderror(0, 0, s, ID_UNKNOWN);
479 if ((size_t)onreadlen > bufsiz)
480 onreadlen = bufsiz;
481 ssize = read(s, &buf[size], (size_t)onreadlen);
482 if (ssize == -1)
483 iderror(0, 0, s, ID_UNKNOWN);
484 else if (ssize == 0)
485 break;
486 bufsiz -= ssize;
487 size += ssize;
488 if (memchr(&buf[size - ssize], '\n', ssize) != NULL)
489 break;
490 }
491 buf[size] = '\0';
492 /* Read two characters, and check for a delimiting character */
493 if (sscanf(buf, "%hu , %hu%c", &lport, &fport, &e) != 3 || isdigit(e))
494 iderror(0, 0, s, ID_INVALID);
495
496 /* Send garbage? */
497 if (gflag)
498 goto printit;
499
500 /*
501 * If not "real" (-r), send a HIDDEN-USER error for everything.
502 * If -d is used to set a fallback username, this is used to
503 * override it, and the fallback is returned instead.
504 */
505 if (!rflag) {
506 if (*idbuf == '\0')
507 iderror(lport, fport, s, ID_HIDDEN);
508 goto printit;
509 }
510
511 /*
512 * We take the input and construct an array of two sockaddr_ins
513 * which contain the local address information and foreign
514 * address information, respectively, used to look up the
515 * credentials for the socket (which are returned by the
516 * sysctl "net.inet.tcp.getcred" when we call it.)
517 */
518 socklen = sizeof(ss[0]);
519 if (getsockname(s, (struct sockaddr *)&ss[0], &socklen) == -1)
520 iderror(lport, fport, s, ID_UNKNOWN);
521 socklen = sizeof(ss[1]);
522 if (getpeername(s, (struct sockaddr *)&ss[1], &socklen) == -1)
523 iderror(lport, fport, s, ID_UNKNOWN);
524 if (ss[0].ss_family != ss[1].ss_family)
525 iderror(lport, fport, s, ID_UNKNOWN);
526 size = sizeof(uc);
527 switch (ss[0].ss_family) {
528 case AF_INET:
529 sin4[0] = *(struct sockaddr_in *)&ss[0];
530 sin4[0].sin_port = htons(lport);
531 sin4[1] = *(struct sockaddr_in *)&ss[1];
532 sin4[1].sin_port = htons(fport);
533 if (sysctlbyname("net.inet.tcp.getcred", &uc, &size, sin4,
534 sizeof(sin4)) == -1)
535 getcredfail = errno;
536 break;
537#ifdef INET6
538 case AF_INET6:
539 sin6[0] = *(struct sockaddr_in6 *)&ss[0];
540 sin6[0].sin6_port = htons(lport);
541 sin6[1] = *(struct sockaddr_in6 *)&ss[1];
542 sin6[1].sin6_port = htons(fport);
543 if (sysctlbyname("net.inet6.tcp6.getcred", &uc, &size, sin6,
544 sizeof(sin6)) == -1)
545 getcredfail = errno;
546 break;
547#endif
548 default: /* should not reach here */
549 getcredfail = EAFNOSUPPORT;
550 break;
551 }
552 if (getcredfail != 0) {
553 if (*idbuf == '\0')
554 iderror(lport, fport, s,
555 getcredfail == ENOENT ? ID_NOUSER : ID_UNKNOWN);
556 goto printit;
557 }
558
559 /* Look up the pw to get the username and home directory*/
560 errno = 0;
561 pw = getpwuid(uc.cr_uid);
562 if (pw == NULL)
563 iderror(lport, fport, s, errno == 0 ? ID_NOUSER : ID_UNKNOWN);
564
565 if (iflag)
566 snprintf(idbuf, sizeof(idbuf), "%u", (unsigned)pw->pw_uid);
567 else
568 strlcpy(idbuf, pw->pw_name, sizeof(idbuf));
569
570 /*
571 * If enabled, we check for a file named ".noident" in the user's
572 * home directory. If found, we return HIDDEN-USER.
573 */
574 if (nflag) {
575 if (asprintf(&p, "%s/.noident", pw->pw_dir) == -1)
576 iderror(lport, fport, s, ID_UNKNOWN);
577 if (lstat(p, &sb) == 0) {
578 free(p);
579 iderror(lport, fport, s, ID_HIDDEN);
580 }
581 free(p);
582 }
583
584 /*
585 * Here, if enabled, we read a user's ".fakeid" file in their
586 * home directory. It consists of a line containing the name
587 * they want.
588 */
589 if (fflag) {
590 int fakeid_fd;
591
592 /*
593 * Here we set ourself to effectively be the user, so we don't
594 * open any files we have no permission to open, especially
595 * symbolic links to sensitive root-owned files or devices.
596 */
597 if (initgroups(pw->pw_name, pw->pw_gid) == -1)
598 iderror(lport, fport, s, ID_UNKNOWN);
599 if (seteuid(pw->pw_uid) == -1)
600 iderror(lport, fport, s, ID_UNKNOWN);
601 /*
602 * We can't stat() here since that would be a race
603 * condition.
604 * Therefore, we open the file we have permissions to open
605 * and if it's not a regular file, we close it and end up
606 * returning the user's real username.
607 */
608 if (asprintf(&p, "%s/.fakeid", pw->pw_dir) == -1)
609 iderror(lport, fport, s, ID_UNKNOWN);
610 fakeid_fd = open(p, O_RDONLY | O_NONBLOCK);
611 free(p);
612 if (fakeid_fd == -1 || fstat(fakeid_fd, &sb) == -1 ||
613 !S_ISREG(sb.st_mode))
614 goto fakeid_fail;
615
616 if ((ssize = read(fakeid_fd, buf, sizeof(buf) - 1)) < 0)
617 goto fakeid_fail;
618 buf[ssize] = '\0';
619
620 /*
621 * Usually, the file will have the desired identity
622 * in the form "identity\n". Allow for leading white
623 * space and trailing white space/end of line.
624 */
625 p = buf;
626 p += strspn(p, " \t");
627 p[strcspn(p, " \t\r\n")] = '\0';
628 if (strlen(p) > MAXLOGNAME - 1) /* Too long (including nul)? */
629 p[MAXLOGNAME - 1] = '\0';
630
631 /*
632 * If the name is a zero-length string or matches it
633 * the id or name of another user (unless permitted by -F)
634 * then it is invalid.
635 */
636 if (*p == '\0')
637 goto fakeid_fail;
638 if (!Fflag) {
639 if (iflag) {
640 if (p[strspn(p, "0123456789")] == '\0' &&
641 getpwuid(atoi(p)) != NULL)
642 goto fakeid_fail;
643 } else {
644 if (getpwnam(p) != NULL)
645 goto fakeid_fail;
646 }
647 }
648
649 strlcpy(idbuf, p, sizeof(idbuf));
650
651fakeid_fail:
652 if (fakeid_fd != -1)
653 close(fakeid_fd);
654 }
655
656printit:
657 /* Finally, we make and send the reply. */
658 if (asprintf(&p, "%d , %d : USERID : %s : %s\r\n", lport, fport, osname,
659 idbuf) == -1) {
660 syslog(LOG_ERR, "asprintf: %m");
661 exit(EX_OSERR);
662 }
663 send(s, p, strlen(p), MSG_EOF);
664 free(p);
665
666 exit(0);
667}
668
669/*
670 * RFC738 Time Server.
671 * Return a machine readable date and time, in the form of the
672 * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
673 * returns the number of seconds since midnight, Jan 1, 1970,
674 * we must add 2208988800 seconds to this figure to make up for
675 * some seventy years Bell Labs was asleep.
676 */
677
678unsigned long
68da13b1 679machtime(void)
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680{
681 struct timeval tv;
682
683 if (gettimeofday(&tv, (struct timezone *)NULL) < 0) {
684 if (debug)
685 warnx("unable to get time of day");
686 return (0L);
687 }
688#define OFFSET ((u_long)25567 * 24*60*60)
689 return (htonl((long)(tv.tv_sec + OFFSET)));
690#undef OFFSET
691}
692
693/* ARGSUSED */
694void
68da13b1 695machtime_dg(int s, struct servtab *sep)
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696{
697 unsigned long result;
698 struct sockaddr_storage ss;
699 socklen_t size;
700
701 size = sizeof(ss);
702 if (recvfrom(s, (char *)&result, sizeof(result), 0,
703 (struct sockaddr *)&ss, &size) < 0)
704 return;
705
706 if (check_loop((struct sockaddr *)&ss, sep))
707 return;
708
709 result = machtime();
71126e33 710 sendto(s, (char *) &result, sizeof(result), 0,
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711 (struct sockaddr *)&ss, size);
712}
713
714/* ARGSUSED */
715void
68da13b1 716machtime_stream(int s, struct servtab *sep __unused)
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717{
718 unsigned long result;
719
720 result = machtime();
71126e33 721 send(s, (char *) &result, sizeof(result), MSG_EOF);
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722}
723
724/*
725 * RFC1078 TCP Port Service Multiplexer (TCPMUX). Service connections to
726 * services based on the service name sent.
727 *
728 * Based on TCPMUX.C by Mark K. Lottor November 1988
729 * sri-nic::ps:<mkl>tcpmux.c
730 */
731
732#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
71126e33 733#define strwrite(fd, buf) write(fd, buf, sizeof(buf)-1)
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734
735static int /* # of characters upto \r,\n or \0 */
68da13b1 736getline(int fd, char *buf, int len)
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737{
738 int count = 0, n;
739 struct sigaction sa;
740
741 sa.sa_flags = 0;
742 sigemptyset(&sa.sa_mask);
743 sa.sa_handler = SIG_DFL;
744 sigaction(SIGALRM, &sa, (struct sigaction *)0);
745 do {
746 alarm(10);
747 n = read(fd, buf, len-count);
748 alarm(0);
749 if (n == 0)
750 return (count);
751 if (n < 0)
752 return (-1);
753 while (--n >= 0) {
754 if (*buf == '\r' || *buf == '\n' || *buf == '\0')
755 return (count);
756 count++;
757 buf++;
758 }
759 } while (count < len);
760 return (count);
761}
762
763struct servtab *
68da13b1 764tcpmux(int s)
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765{
766 struct servtab *sep;
767 char service[MAX_SERV_LEN+1];
768 int len;
769
770 /* Get requested service name */
771 if ((len = getline(s, service, MAX_SERV_LEN)) < 0) {
772 strwrite(s, "-Error reading service name\r\n");
773 return (NULL);
774 }
775 service[len] = '\0';
776
777 if (debug)
778 warnx("tcpmux: someone wants %s", service);
779
780 /*
781 * Help is a required command, and lists available services,
782 * one per line.
783 */
784 if (!strcasecmp(service, "help")) {
785 for (sep = servtab; sep; sep = sep->se_next) {
786 if (!ISMUX(sep))
787 continue;
71126e33 788 write(s,sep->se_service,strlen(sep->se_service));
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789 strwrite(s, "\r\n");
790 }
791 return (NULL);
792 }
793
794 /* Try matching a service in inetd.conf with the request */
795 for (sep = servtab; sep; sep = sep->se_next) {
796 if (!ISMUX(sep))
797 continue;
798 if (!strcasecmp(service, sep->se_service)) {
799 if (ISMUXPLUS(sep)) {
800 strwrite(s, "+Go\r\n");
801 }
802 return (sep);
803 }
804 }
805 strwrite(s, "-Service not available\r\n");
806 return (NULL);
807}