xref: /openbsd-src/usr.sbin/pppd/sys-bsd.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
1 /*	$OpenBSD: sys-bsd.c,v 1.21 2003/05/14 02:02:56 itojun Exp $	*/
2 
3 /*
4  * sys-bsd.c - System-dependent procedures for setting up
5  * PPP interfaces on bsd-4.4-ish systems (including 386BSD, NetBSD, etc.)
6  *
7  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. The name "Carnegie Mellon University" must not be used to
22  *    endorse or promote products derived from this software without
23  *    prior written permission. For permission or any legal
24  *    details, please contact
25  *      Office of Technology Transfer
26  *      Carnegie Mellon University
27  *      5000 Forbes Avenue
28  *      Pittsburgh, PA  15213-3890
29  *      (412) 268-4387, fax: (412) 268-7395
30  *      tech-transfer@andrew.cmu.edu
31  *
32  * 4. Redistributions of any form whatsoever must retain the following
33  *    acknowledgment:
34  *    "This product includes software developed by Computing Services
35  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
36  *
37  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
38  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
39  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
40  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
41  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
42  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
43  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
44  *
45  * Copyright (c) 1989-2002 Paul Mackerras. All rights reserved.
46  *
47  * Redistribution and use in source and binary forms, with or without
48  * modification, are permitted provided that the following conditions
49  * are met:
50  *
51  * 1. Redistributions of source code must retain the above copyright
52  *    notice, this list of conditions and the following disclaimer.
53  *
54  * 2. Redistributions in binary form must reproduce the above copyright
55  *    notice, this list of conditions and the following disclaimer in
56  *    the documentation and/or other materials provided with the
57  *    distribution.
58  *
59  * 3. The name(s) of the authors of this software must not be used to
60  *    endorse or promote products derived from this software without
61  *    prior written permission.
62  *
63  * 4. Redistributions of any form whatsoever must retain the following
64  *    acknowledgment:
65  *    "This product includes software developed by Paul Mackerras
66  *     <paulus@samba.org>".
67  *
68  * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
69  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
70  * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
71  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
72  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
73  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
74  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
75  */
76 
77 #ifndef lint
78 #if 0
79 static char rcsid[] = "Id: sys-bsd.c,v 1.31 1998/04/02 12:04:19 paulus Exp $";
80 #else
81 static char rcsid[] = "$OpenBSD: sys-bsd.c,v 1.21 2003/05/14 02:02:56 itojun Exp $";
82 #endif
83 #endif
84 
85 /*
86  * TODO:
87  */
88 
89 #include <stdio.h>
90 #include <syslog.h>
91 #include <string.h>
92 #include <stdlib.h>
93 #include <unistd.h>
94 #include <err.h>
95 #include <errno.h>
96 #include <fcntl.h>
97 #include <termios.h>
98 #include <signal.h>
99 #include <util.h>
100 #include <sys/ioctl.h>
101 #include <sys/types.h>
102 #include <sys/socket.h>
103 #include <sys/time.h>
104 #include <sys/stat.h>
105 
106 #ifdef PPP_FILTER
107 #include <net/bpf.h>
108 #endif
109 #include <net/if.h>
110 #include <net/ppp_defs.h>
111 #include <net/if_ppp.h>
112 #include <net/route.h>
113 #include <net/if_dl.h>
114 #include <netinet/in.h>
115 
116 #if RTM_VERSION >= 3
117 #include <sys/param.h>
118 #if defined(NetBSD) && (NetBSD >= 199703)
119 #include <netinet/if_inarp.h>
120 #else	/* NetBSD 1.2D or later */
121 #if defined(__FreeBSD__) || defined(__OpenBSD__)
122 #include <netinet/if_ether.h>
123 #else
124 #include <net/if_ether.h>
125 #endif
126 #endif
127 #endif
128 
129 #include "pppd.h"
130 #include "fsm.h"
131 #include "ipcp.h"
132 
133 #ifdef IPX_CHANGE
134 #include <netipx/ipx.h>
135 #include <netipx/ipx_if.h>
136 #include "ipxcp.h"
137 #endif
138 
139 #define ok_error(num) ((num)==EIO)
140 
141 static int initdisc = -1;	/* Initial TTY discipline for ppp_fd */
142 static int initfdflags = -1;	/* Initial file descriptor flags for ppp_fd */
143 static int ppp_fd = -1;		/* fd which is set to PPP discipline */
144 static int rtm_seq;
145 
146 static int restore_term;	/* 1 => we've munged the terminal */
147 static struct termios inittermios; /* Initial TTY termios */
148 static struct winsize wsinfo;	/* Initial window size info */
149 
150 static char *lock_file;		/* name of lock file created */
151 
152 static int loop_slave = -1;
153 static int loop_master;
154 static char loop_name[20];
155 
156 static unsigned char inbuf[512]; /* buffer for chars read from loopback */
157 
158 static int sockfd;		/* socket for doing interface ioctls */
159 
160 static int if_is_up;		/* the interface is currently up */
161 static u_int32_t ifaddrs[2];	/* local and remote addresses we set */
162 static u_int32_t default_route_gateway;	/* gateway addr for default route */
163 static u_int32_t proxy_arp_addr;	/* remote addr for proxy arp */
164 
165 /* Prototypes for procedures local to this file. */
166 static int dodefaultroute(u_int32_t, int);
167 static int get_ether_addr(u_int32_t, struct sockaddr_dl *);
168 
169 
170 /*
171  * sys_init - System-dependent initialization.
172  */
173 void
174 sys_init()
175 {
176     /* Get an internet socket for doing socket ioctl's on. */
177     if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
178 	syslog(LOG_ERR, "Couldn't create IP socket: %m");
179 	die(1);
180     }
181 }
182 
183 /*
184  * sys_cleanup - restore any system state we modified before exiting:
185  * mark the interface down, delete default route and/or proxy arp entry.
186  * This should call die() because it's called from die().
187  */
188 void
189 sys_cleanup()
190 {
191     struct ifreq ifr;
192 
193     if (if_is_up) {
194 	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
195 	if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) >= 0
196 	    && ((ifr.ifr_flags & IFF_UP) != 0)) {
197 	    ifr.ifr_flags &= ~IFF_UP;
198 	    ioctl(sockfd, SIOCSIFFLAGS, &ifr);
199 	}
200     }
201     if (ifaddrs[0] != 0)
202 	cifaddr(0, ifaddrs[0], ifaddrs[1]);
203     if (default_route_gateway)
204 	cifdefaultroute(0, 0, default_route_gateway);
205     if (proxy_arp_addr)
206 	cifproxyarp(0, proxy_arp_addr);
207 }
208 
209 /*
210  * sys_close - Clean up in a child process before execing.
211  */
212 void
213 sys_close()
214 {
215     close(sockfd);
216     if (loop_slave >= 0) {
217 	close(loop_slave);
218 	close(loop_master);
219     }
220 }
221 
222 /*
223  * sys_check_options - check the options that the user specified
224  */
225 void
226 sys_check_options()
227 {
228 }
229 
230 /*
231  * ppp_available - check whether the system has any ppp interfaces
232  * (in fact we check whether we can do an ioctl on ppp0).
233  */
234 int
235 ppp_available()
236 {
237     int s, ok;
238     struct ifreq ifr;
239     extern char *no_ppp_msg;
240 
241     if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
242 	return 1;		/* can't tell */
243 
244     strlcpy(ifr.ifr_name, "ppp0", sizeof(ifr.ifr_name));
245     ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0;
246     close(s);
247 
248     no_ppp_msg = "\
249 This system lacks kernel support for PPP.  To include PPP support\n\
250 in the kernel, please add a line\n\
251 \tpseudo-device ppp 1\n\
252 to your kernel config file and build a new kernel.\n";
253     return ok;
254 }
255 
256 /*
257  * establish_ppp - Turn the serial port into a ppp interface.
258  */
259 void
260 establish_ppp(fd)
261     int fd;
262 {
263     int pppdisc = PPPDISC;
264     int x;
265 
266     if (demand) {
267 	/*
268 	 * Demand mode - prime the old ppp device to relinquish the unit.
269 	 */
270 	if (ioctl(ppp_fd, PPPIOCXFERUNIT, 0) < 0) {
271 	    syslog(LOG_ERR, "ioctl(transfer ppp unit): %m");
272 	    die(1);
273 	}
274     }
275 
276     /*
277      * Save the old line discipline of fd, and set it to PPP.
278      */
279     if (ioctl(fd, TIOCGETD, &initdisc) < 0) {
280 	syslog(LOG_ERR, "ioctl(TIOCGETD): %m");
281 	die(1);
282     }
283     if (ioctl(fd, TIOCSETD, &pppdisc) < 0) {
284 	syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
285 	die(1);
286     }
287 
288     if (!demand) {
289 	/*
290 	 * Find out which interface we were given.
291 	 */
292 	if (ioctl(fd, PPPIOCGUNIT, &ifunit) < 0) {
293 	    syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m");
294 	    die(1);
295 	}
296     } else {
297 	/*
298 	 * Check that we got the same unit again.
299 	 */
300 	if (ioctl(fd, PPPIOCGUNIT, &x) < 0) {
301 	    syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m");
302 	    die(1);
303 	}
304 	if (x != ifunit) {
305 	    syslog(LOG_ERR, "transfer_ppp failed: wanted unit %d, got %d",
306 		   ifunit, x);
307 	    die(1);
308 	}
309 	x = TTYDISC;
310 	ioctl(loop_slave, TIOCSETD, &x);
311     }
312 
313     ppp_fd = fd;
314 
315     /*
316      * Enable debug in the driver if requested.
317      */
318     if (kdebugflag) {
319 	if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
320 	    syslog(LOG_WARNING, "ioctl (PPPIOCGFLAGS): %m");
321 	} else {
322 	    x |= (kdebugflag & 0xFF) * SC_DEBUG;
323 	    if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0)
324 		syslog(LOG_WARNING, "ioctl(PPPIOCSFLAGS): %m");
325 	}
326     }
327 
328     /*
329      * Set device for non-blocking reads.
330      */
331     if ((initfdflags = fcntl(fd, F_GETFL)) == -1
332 	|| fcntl(fd, F_SETFL, initfdflags | O_NONBLOCK) == -1) {
333 	syslog(LOG_WARNING, "Couldn't set device to non-blocking mode: %m");
334     }
335 }
336 
337 /*
338  * restore_loop - reattach the ppp unit to the loopback.
339  */
340 void
341 restore_loop()
342 {
343     int x;
344 
345     /*
346      * Transfer the ppp interface back to the loopback.
347      */
348     if (ioctl(ppp_fd, PPPIOCXFERUNIT, 0) < 0) {
349 	syslog(LOG_ERR, "ioctl(transfer ppp unit): %m");
350 	die(1);
351     }
352     x = PPPDISC;
353     if (ioctl(loop_slave, TIOCSETD, &x) < 0) {
354 	syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
355 	die(1);
356     }
357 
358     /*
359      * Check that we got the same unit again.
360      */
361     if (ioctl(loop_slave, PPPIOCGUNIT, &x) < 0) {
362 	syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m");
363 	die(1);
364     }
365     if (x != ifunit) {
366 	syslog(LOG_ERR, "transfer_ppp failed: wanted unit %d, got %d",
367 	       ifunit, x);
368 	die(1);
369     }
370     ppp_fd = loop_slave;
371 }
372 
373 #ifdef IPX_CHANGE
374 /*
375  * sipxfaddr - Config the interface IPX networknumber
376  */
377 int
378 sipxfaddr(unit, network, node)
379 	  int unit;
380 	  u_int32_t network;
381 	  u_char * node;
382 {
383 	int    skfd;
384 	int    result = 1;
385 	struct ifreq         ifr;
386 	struct sockaddr_ipx *sipx = (struct sockaddr_ipx *) &ifr.ifr_addr;
387 
388 	skfd = socket (AF_IPX, SOCK_DGRAM, 0);
389 	if (skfd < 0) {
390 		if (!ok_error (errno))
391 			syslog (LOG_DEBUG, "socket(AF_IPX): %m(%d)", errno);
392 		result = 0;
393 	} else {
394 		bzero (&ifr, sizeof(ifr));
395 		strlcpy (ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
396 
397 		sipx->sipx_len     = sizeof(*sipx);
398 		sipx->sipx_family  = AF_IPX;
399 		sipx->sipx_type    = IPX_ETHERTYPE_II;
400 		sipx->sipx_port    = 0;
401 		sipx->sipx_network = htonl (network);
402 		memcpy (sipx->sipx_node, node, IPX_HOSTADDRLEN);
403 
404 		/*
405 		 *  Set the IPX device
406 		 */
407 		if (ioctl(skfd, SIOCSIFADDR, (caddr_t) &ifr) < 0) {
408 			result = 0;
409 			if (errno != EEXIST && !ok_error (errno)) {
410 				syslog (LOG_DEBUG,
411 					"ioctl(SIOCAIFADDR, CRTITF): %m(%d)",
412 					errno);
413 			} else {
414 				syslog (LOG_WARNING,
415 					"ioctl(SIOCAIFADDR, CRTITF): Address already exists");
416 			}
417 		}
418 		close (skfd);
419 	}
420 
421 	return result;
422 }
423 
424 /*
425  * cipxfaddr - Clear the information for the IPX network. The IPX routes
426  *	       are removed and the device is no longer able to pass IPX
427  *	       frames.
428  */
429 int
430 cipxfaddr(unit)
431 	int unit;
432 {
433 	int    skfd;
434 	int    result = 1;
435 	struct ifreq         ifr;
436 	struct sockaddr_ipx *sipx = (struct sockaddr_ipx *) &ifr.ifr_addr;
437 
438 	skfd = socket (AF_IPX, SOCK_DGRAM, 0);
439 	if (skfd < 0) {
440 		if (! ok_error (errno))
441 			syslog (LOG_DEBUG, "socket(AF_IPX): %m(%d)", errno);
442 		result = 0;
443 	} else {
444 		bzero (&ifr, sizeof(ifr));
445 		strlcpy (ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
446 
447 		sipx->sipx_len     = sizeof(*sipx);
448 		sipx->sipx_family  = AF_IPX;
449 		sipx->sipx_type    = IPX_ETHERTYPE_II;
450 
451 		/*
452 		 *  Set the IPX device
453 		 */
454 		if (ioctl(skfd, SIOCDIFADDR, (caddr_t) &ifr) < 0) {
455 			if (!ok_error (errno))
456 				syslog (LOG_INFO,
457 					"ioctl(SIOCAIFADDR, IPX_DLTITF): %m(%d)",
458 					errno);
459 			result = 0;
460 		}
461 		close (skfd);
462 	}
463 
464 	return result;
465 }
466 #endif
467 
468 /*
469  * disestablish_ppp - Restore the serial port to normal operation.
470  * This shouldn't call die() because it's called from die().
471  */
472 void
473 disestablish_ppp(fd)
474     int fd;
475 {
476     /* Reset non-blocking mode on fd. */
477     if (initfdflags != -1 && fcntl(fd, F_SETFL, initfdflags) < 0)
478 	syslog(LOG_WARNING, "Couldn't restore device fd flags: %m");
479     initfdflags = -1;
480 
481     /* Restore old line discipline. */
482     if (initdisc >= 0 && ioctl(fd, TIOCSETD, &initdisc) < 0)
483 	syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
484     initdisc = -1;
485 
486     if (fd == ppp_fd)
487 	ppp_fd = -1;
488 }
489 
490 /*
491  * Check whether the link seems not to be 8-bit clean.
492  */
493 void
494 clean_check()
495 {
496     int x;
497     char *s;
498 
499     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) == 0) {
500 	s = NULL;
501 	switch (~x & (SC_RCV_B7_0|SC_RCV_B7_1|SC_RCV_EVNP|SC_RCV_ODDP)) {
502 	case SC_RCV_B7_0:
503 	    s = "bit 7 set to 1";
504 	    break;
505 	case SC_RCV_B7_1:
506 	    s = "bit 7 set to 0";
507 	    break;
508 	case SC_RCV_EVNP:
509 	    s = "odd parity";
510 	    break;
511 	case SC_RCV_ODDP:
512 	    s = "even parity";
513 	    break;
514 	}
515 	if (s != NULL) {
516 	    syslog(LOG_WARNING, "Serial link is not 8-bit clean:");
517 	    syslog(LOG_WARNING, "All received characters had %s", s);
518 	}
519     }
520 }
521 
522 /*
523  * set_up_tty: Set up the serial port on `fd' for 8 bits, no parity,
524  * at the requested speed, etc.  If `local' is true, set CLOCAL
525  * regardless of whether the modem option was specified.
526  *
527  * For *BSD, we assume that speed_t values numerically equal bits/second.
528  */
529 void
530 set_up_tty(fd, local)
531     int fd, local;
532 {
533     struct termios tios;
534 
535     if (tcgetattr(fd, &tios) < 0) {
536 	syslog(LOG_ERR, "tcgetattr: %m");
537 	die(1);
538     }
539 
540     if (!restore_term) {
541 	inittermios = tios;
542 	ioctl(fd, TIOCGWINSZ, &wsinfo);
543     }
544 
545     tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB | CLOCAL);
546     if (crtscts > 0 && modem)
547 	tios.c_cflag |= CRTSCTS;
548     else if (crtscts < 0)
549 	tios.c_cflag &= ~CRTSCTS;
550 
551     tios.c_cflag |= CS8 | CREAD | HUPCL;
552     if (local || !modem)
553 	tios.c_cflag |= CLOCAL;
554     tios.c_iflag = IGNBRK | IGNPAR;
555     tios.c_oflag = 0;
556     tios.c_lflag = 0;
557     tios.c_cc[VMIN] = 1;
558     tios.c_cc[VTIME] = 0;
559 
560     if (crtscts == -2) {
561 	tios.c_iflag |= IXON | IXOFF;
562 	tios.c_cc[VSTOP] = 0x13;	/* DC3 = XOFF = ^S */
563 	tios.c_cc[VSTART] = 0x11;	/* DC1 = XON  = ^Q */
564     }
565 
566     if (inspeed) {
567 	cfsetospeed(&tios, inspeed);
568 	cfsetispeed(&tios, inspeed);
569     } else {
570 	inspeed = cfgetospeed(&tios);
571 	/*
572 	 * We can't proceed if the serial port speed is 0,
573 	 * since that implies that the serial port is disabled.
574 	 */
575 	if (inspeed == 0) {
576 	    syslog(LOG_ERR, "Baud rate for %s is 0; need explicit baud rate",
577 		   devnam);
578 	    die(1);
579 	}
580     }
581     baud_rate = inspeed;
582 
583     if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
584 	syslog(LOG_ERR, "tcsetattr: %m");
585 	die(1);
586     }
587 
588     restore_term = 1;
589 }
590 
591 /*
592  * restore_tty - restore the terminal to the saved settings.
593  */
594 void
595 restore_tty(fd)
596     int fd;
597 {
598     if (restore_term) {
599 	if (!default_device) {
600 	    /*
601 	     * Turn off echoing, because otherwise we can get into
602 	     * a loop with the tty and the modem echoing to each other.
603 	     * We presume we are the sole user of this tty device, so
604 	     * when we close it, it will revert to its defaults anyway.
605 	     */
606 	    inittermios.c_lflag &= ~(ECHO | ECHONL);
607 	}
608 	if (tcsetattr(fd, TCSAFLUSH, &inittermios) < 0)
609 	    if (errno != ENXIO)
610 		syslog(LOG_WARNING, "tcsetattr: %m");
611 	ioctl(fd, TIOCSWINSZ, &wsinfo);
612 	restore_term = 0;
613     }
614 }
615 
616 /*
617  * setdtr - control the DTR line on the serial port.
618  * This is called from die(), so it shouldn't call die().
619  */
620 void
621 setdtr(fd, on)
622 int fd, on;
623 {
624     int modembits = TIOCM_DTR;
625 
626     ioctl(fd, (on? TIOCMBIS: TIOCMBIC), &modembits);
627 }
628 
629 
630 /*
631  * open_ppp_loopback - open the device we use for getting
632  * packets in demand mode, and connect it to a ppp interface.
633  * Here we use a pty.
634  */
635 void
636 open_ppp_loopback()
637 {
638     int flags;
639     struct termios tios;
640     int pppdisc = PPPDISC;
641 
642     if (openpty(&loop_master, &loop_slave, loop_name, NULL, NULL) < 0) {
643 	syslog(LOG_ERR, "No free pty for loopback");
644 	die(1);
645     }
646     SYSDEBUG((LOG_DEBUG, "using %s for loopback", loop_name));
647 
648     if (tcgetattr(loop_slave, &tios) == 0) {
649 	tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB);
650 	tios.c_cflag |= CS8 | CREAD;
651 	tios.c_iflag = IGNPAR;
652 	tios.c_oflag = 0;
653 	tios.c_lflag = 0;
654 	if (tcsetattr(loop_slave, TCSAFLUSH, &tios) < 0)
655 	    syslog(LOG_WARNING, "couldn't set attributes on loopback: %m");
656     }
657 
658     if ((flags = fcntl(loop_master, F_GETFL)) != -1)
659 	if (fcntl(loop_master, F_SETFL, flags | O_NONBLOCK) == -1)
660 	    syslog(LOG_WARNING, "couldn't set loopback to nonblock: %m");
661 
662     ppp_fd = loop_slave;
663     if (ioctl(ppp_fd, TIOCSETD, &pppdisc) < 0) {
664 	syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
665 	die(1);
666     }
667 
668     /*
669      * Find out which interface we were given.
670      */
671     if (ioctl(ppp_fd, PPPIOCGUNIT, &ifunit) < 0) {
672 	syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m");
673 	die(1);
674     }
675 
676     /*
677      * Enable debug in the driver if requested.
678      */
679     if (kdebugflag) {
680 	if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &flags) < 0) {
681 	    syslog(LOG_WARNING, "ioctl (PPPIOCGFLAGS): %m");
682 	} else {
683 	    flags |= (kdebugflag & 0xFF) * SC_DEBUG;
684 	    if (ioctl(ppp_fd, PPPIOCSFLAGS, (caddr_t) &flags) < 0)
685 		syslog(LOG_WARNING, "ioctl(PPPIOCSFLAGS): %m");
686 	}
687     }
688 
689 }
690 
691 
692 /*
693  * output - Output PPP packet.
694  */
695 void
696 output(unit, p, len)
697     int unit;
698     u_char *p;
699     int len;
700 {
701     if (debug)
702 	log_packet(p, len, "sent ", LOG_DEBUG);
703 
704     if (write(ttyfd, p, len) < 0) {
705 	if (errno != EIO)
706 	    syslog(LOG_ERR, "write: %m");
707     }
708 }
709 
710 
711 /*
712  * wait_input - wait until there is data available on ttyfd,
713  * for the length of time specified by *timo (indefinite
714  * if timo is NULL).
715  */
716 void
717 wait_input(timo)
718     struct timeval *timo;
719 {
720     fd_set *fdsp = NULL;
721     int fdsn;
722     int n;
723 
724     fdsn = howmany(ttyfd+1, NFDBITS) * sizeof(fd_mask);
725     if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
726 	err(1, "malloc");
727     memset(fdsp, 0, fdsn);
728     FD_SET(ttyfd, fdsp);
729 
730     n = select(ttyfd+1, fdsp, NULL, fdsp, timo);
731     if (n < 0 && errno != EINTR) {
732 	syslog(LOG_ERR, "select: %m");
733 	free(fdsp);
734 	die(1);
735     }
736     free(fdsp);
737 }
738 
739 
740 /*
741  * wait_loop_output - wait until there is data available on the
742  * loopback, for the length of time specified by *timo (indefinite
743  * if timo is NULL).
744  */
745 void
746 wait_loop_output(timo)
747     struct timeval *timo;
748 {
749     fd_set *fdsp = NULL;
750     int fdsn;
751     int n;
752 
753     fdsn = howmany(loop_master+1, NFDBITS) * sizeof(fd_mask);
754     if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
755 	err(1, "malloc");
756     memset(fdsp, 0, fdsn);
757     FD_SET(loop_master, fdsp);
758 
759     n = select(loop_master + 1, fdsp, NULL, fdsp, timo);
760     if (n < 0 && errno != EINTR) {
761 	syslog(LOG_ERR, "select: %m");
762 	free(fdsp);
763 	die(1);
764     }
765     free(fdsp);
766 }
767 
768 
769 /*
770  * wait_time - wait for a given length of time or until a
771  * signal is received.
772  */
773 void
774 wait_time(timo)
775     struct timeval *timo;
776 {
777     int n;
778 
779     n = select(0, NULL, NULL, NULL, timo);
780     if (n < 0 && errno != EINTR) {
781 	syslog(LOG_ERR, "select: %m");
782 	die(1);
783     }
784 }
785 
786 
787 /*
788  * read_packet - get a PPP packet from the serial device.
789  */
790 int
791 read_packet(buf)
792     u_char *buf;
793 {
794     int len;
795 
796     if ((len = read(ttyfd, buf, PPP_MTU + PPP_HDRLEN)) < 0) {
797 	if (errno == EWOULDBLOCK || errno == EINTR)
798 	    return -1;
799 	syslog(LOG_ERR, "read: %m");
800 	die(1);
801     }
802     return len;
803 }
804 
805 
806 /*
807  * get_loop_output - read characters from the loopback, form them
808  * into frames, and detect when we want to bring the real link up.
809  * Return value is 1 if we need to bring up the link, 0 otherwise.
810  */
811 int
812 get_loop_output()
813 {
814     int rv = 0;
815     int n;
816 
817     while ((n = read(loop_master, inbuf, sizeof(inbuf))) >= 0) {
818 	if (loop_chars(inbuf, n))
819 	    rv = 1;
820     }
821 
822     if (n == 0) {
823 	syslog(LOG_ERR, "eof on loopback");
824 	die(1);
825     } else if (errno != EWOULDBLOCK){
826 	syslog(LOG_ERR, "read from loopback: %m");
827 	die(1);
828     }
829 
830     return rv;
831 }
832 
833 
834 /*
835  * ppp_send_config - configure the transmit characteristics of
836  * the ppp interface.
837  */
838 void
839 ppp_send_config(unit, mtu, asyncmap, pcomp, accomp)
840     int unit, mtu;
841     u_int32_t asyncmap;
842     int pcomp, accomp;
843 {
844     u_int x;
845     struct ifreq ifr;
846 
847     strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
848     ifr.ifr_mtu = mtu;
849     if (ioctl(sockfd, SIOCSIFMTU, (caddr_t) &ifr) < 0) {
850 	syslog(LOG_ERR, "ioctl(SIOCSIFMTU): %m");
851 	quit();
852     }
853 
854     if (ioctl(ppp_fd, PPPIOCSASYNCMAP, (caddr_t) &asyncmap) < 0) {
855 	syslog(LOG_ERR, "ioctl(PPPIOCSASYNCMAP): %m");
856 	quit();
857     }
858 
859     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
860 	syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
861 	quit();
862     }
863     x = pcomp? x | SC_COMP_PROT: x &~ SC_COMP_PROT;
864     x = accomp? x | SC_COMP_AC: x &~ SC_COMP_AC;
865     if (ioctl(ppp_fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
866 	syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
867 	quit();
868     }
869 }
870 
871 
872 /*
873  * ppp_set_xaccm - set the extended transmit ACCM for the interface.
874  */
875 void
876 ppp_set_xaccm(unit, accm)
877     int unit;
878     ext_accm accm;
879 {
880     if (ioctl(ppp_fd, PPPIOCSXASYNCMAP, accm) < 0 && errno != ENOTTY)
881 	syslog(LOG_WARNING, "ioctl(set extended ACCM): %m");
882 }
883 
884 
885 /*
886  * ppp_recv_config - configure the receive-side characteristics of
887  * the ppp interface.
888  */
889 void
890 ppp_recv_config(unit, mru, asyncmap, pcomp, accomp)
891     int unit, mru;
892     u_int32_t asyncmap;
893     int pcomp, accomp;
894 {
895     int x;
896 
897     if (ioctl(ppp_fd, PPPIOCSMRU, (caddr_t) &mru) < 0) {
898 	syslog(LOG_ERR, "ioctl(PPPIOCSMRU): %m");
899 	quit();
900     }
901     if (ioctl(ppp_fd, PPPIOCSRASYNCMAP, (caddr_t) &asyncmap) < 0) {
902 	syslog(LOG_ERR, "ioctl(PPPIOCSRASYNCMAP): %m");
903 	quit();
904     }
905     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
906 	syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
907 	quit();
908     }
909     x = !accomp? x | SC_REJ_COMP_AC: x &~ SC_REJ_COMP_AC;
910     if (ioctl(ppp_fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
911 	syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
912 	quit();
913     }
914 }
915 
916 /*
917  * ccp_test - ask kernel whether a given compression method
918  * is acceptable for use.  Returns 1 if the method and parameters
919  * are OK, 0 if the method is known but the parameters are not OK
920  * (e.g. code size should be reduced), or -1 if the method is unknown.
921  */
922 int
923 ccp_test(unit, opt_ptr, opt_len, for_transmit)
924     int unit, opt_len, for_transmit;
925     u_char *opt_ptr;
926 {
927     struct ppp_option_data data;
928 
929     data.ptr = opt_ptr;
930     data.length = opt_len;
931     data.transmit = for_transmit;
932     if (ioctl(ttyfd, PPPIOCSCOMPRESS, (caddr_t) &data) >= 0)
933 	return 1;
934     return (errno == ENOBUFS)? 0: -1;
935 }
936 
937 /*
938  * ccp_flags_set - inform kernel about the current state of CCP.
939  */
940 void
941 ccp_flags_set(unit, isopen, isup)
942     int unit, isopen, isup;
943 {
944     int x;
945 
946     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
947 	syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
948 	return;
949     }
950     x = isopen? x | SC_CCP_OPEN: x &~ SC_CCP_OPEN;
951     x = isup? x | SC_CCP_UP: x &~ SC_CCP_UP;
952     if (ioctl(ppp_fd, PPPIOCSFLAGS, (caddr_t) &x) < 0)
953 	syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
954 }
955 
956 /*
957  * ccp_fatal_error - returns 1 if decompression was disabled as a
958  * result of an error detected after decompression of a packet,
959  * 0 otherwise.  This is necessary because of patent nonsense.
960  */
961 int
962 ccp_fatal_error(unit)
963     int unit;
964 {
965     int x;
966 
967     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
968 	syslog(LOG_ERR, "ioctl(PPPIOCGFLAGS): %m");
969 	return 0;
970     }
971     return x & SC_DC_FERROR;
972 }
973 
974 /*
975  * get_idle_time - return how long the link has been idle.
976  */
977 int
978 get_idle_time(u, ip)
979     int u;
980     struct ppp_idle *ip;
981 {
982     return ioctl(ppp_fd, PPPIOCGIDLE, ip) >= 0;
983 }
984 
985 
986 #ifdef PPP_FILTER
987 /*
988  * set_filters - transfer the pass and active filters to the kernel.
989  */
990 int
991 set_filters(pass, active)
992     struct bpf_program *pass, *active;
993 {
994     int ret = 1;
995 
996     if (pass->bf_len > 0) {
997 	if (ioctl(ppp_fd, PPPIOCSPASS, pass) < 0) {
998 	    syslog(LOG_ERR, "Couldn't set pass-filter in kernel: %m");
999 	    ret = 0;
1000 	}
1001     }
1002     if (active->bf_len > 0) {
1003 	if (ioctl(ppp_fd, PPPIOCSACTIVE, active) < 0) {
1004 	    syslog(LOG_ERR, "Couldn't set active-filter in kernel: %m");
1005 	    ret = 0;
1006 	}
1007     }
1008     return ret;
1009 }
1010 #endif
1011 
1012 /*
1013  * sifvjcomp - config tcp header compression
1014  */
1015 int
1016 sifvjcomp(u, vjcomp, cidcomp, maxcid)
1017     int u, vjcomp, cidcomp, maxcid;
1018 {
1019     u_int x;
1020 
1021     if (ioctl(ppp_fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
1022 	syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
1023 	return 0;
1024     }
1025     x = vjcomp ? x | SC_COMP_TCP: x &~ SC_COMP_TCP;
1026     x = cidcomp? x & ~SC_NO_TCP_CCID: x | SC_NO_TCP_CCID;
1027     if (ioctl(ppp_fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
1028 	syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
1029 	return 0;
1030     }
1031     if (vjcomp && ioctl(ppp_fd, PPPIOCSMAXCID, (caddr_t) &maxcid) < 0) {
1032 	syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
1033 	return 0;
1034     }
1035     return 1;
1036 }
1037 
1038 /*
1039  * sifup - Config the interface up and enable IP packets to pass.
1040  */
1041 int
1042 sifup(u)
1043     int u;
1044 {
1045     struct ifreq ifr;
1046 
1047     strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
1048     if (ioctl(sockfd, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) {
1049 	syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
1050 	return 0;
1051     }
1052     ifr.ifr_flags |= IFF_UP;
1053     if (ioctl(sockfd, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) {
1054 	syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m");
1055 	return 0;
1056     }
1057     if_is_up = 1;
1058     return 1;
1059 }
1060 
1061 /*
1062  * sifnpmode - Set the mode for handling packets for a given NP.
1063  */
1064 int
1065 sifnpmode(u, proto, mode)
1066     int u;
1067     int proto;
1068     enum NPmode mode;
1069 {
1070     struct npioctl npi;
1071 
1072     npi.protocol = proto;
1073     npi.mode = mode;
1074     if (ioctl(ppp_fd, PPPIOCSNPMODE, &npi) < 0) {
1075 	syslog(LOG_ERR, "ioctl(set NP %d mode to %d): %m", proto, mode);
1076 	return 0;
1077     }
1078     return 1;
1079 }
1080 
1081 /*
1082  * sifdown - Config the interface down and disable IP.
1083  */
1084 int
1085 sifdown(u)
1086     int u;
1087 {
1088     struct ifreq ifr;
1089     int rv;
1090     struct npioctl npi;
1091 
1092     rv = 1;
1093     npi.protocol = PPP_IP;
1094     npi.mode = NPMODE_ERROR;
1095     ioctl(ppp_fd, PPPIOCSNPMODE, (caddr_t) &npi);
1096     /* ignore errors, because ppp_fd might have been closed by now. */
1097 
1098     strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
1099     if (ioctl(sockfd, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) {
1100 	syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
1101 	rv = 0;
1102     } else {
1103 	ifr.ifr_flags &= ~IFF_UP;
1104 	if (ioctl(sockfd, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) {
1105 	    syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m");
1106 	    rv = 0;
1107 	} else
1108 	    if_is_up = 0;
1109     }
1110     return rv;
1111 }
1112 
1113 /*
1114  * SET_SA_FAMILY - set the sa_family field of a struct sockaddr,
1115  * if it exists.
1116  */
1117 #define SET_SA_FAMILY(addr, family)		\
1118     BZERO((char *) &(addr), sizeof(addr));	\
1119     addr.sa_family = (family); 			\
1120     addr.sa_len = sizeof(addr);
1121 
1122 /*
1123  * sifaddr - Config the interface IP addresses and netmask.
1124  */
1125 int
1126 sifaddr(u, o, h, m)
1127     int u;
1128     u_int32_t o, h, m;
1129 {
1130     struct ifaliasreq ifra;
1131     struct ifreq ifr;
1132 
1133     strlcpy(ifra.ifra_name, ifname, sizeof(ifra.ifra_name));
1134     SET_SA_FAMILY(ifra.ifra_addr, AF_INET);
1135     ((struct sockaddr_in *) &ifra.ifra_addr)->sin_addr.s_addr = o;
1136     SET_SA_FAMILY(ifra.ifra_broadaddr, AF_INET);
1137     ((struct sockaddr_in *) &ifra.ifra_broadaddr)->sin_addr.s_addr = h;
1138     if (m != 0) {
1139 	SET_SA_FAMILY(ifra.ifra_mask, AF_INET);
1140 	((struct sockaddr_in *) &ifra.ifra_mask)->sin_addr.s_addr = m;
1141     } else
1142 	BZERO(&ifra.ifra_mask, sizeof(ifra.ifra_mask));
1143     BZERO(&ifr, sizeof(ifr));
1144     strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
1145     if (ioctl(sockfd, SIOCDIFADDR, (caddr_t) &ifr) < 0) {
1146 	if (errno != EADDRNOTAVAIL)
1147 	    syslog(LOG_WARNING, "Couldn't remove interface address: %m");
1148     }
1149     if (ioctl(sockfd, SIOCAIFADDR, (caddr_t) &ifra) < 0) {
1150 	if (errno != EEXIST) {
1151 	    syslog(LOG_ERR, "Couldn't set interface address: %m");
1152 	    return 0;
1153 	}
1154 	syslog(LOG_WARNING,
1155 	       "Couldn't set interface address: Address %s already exists",
1156 	       ip_ntoa(o));
1157     }
1158     ifaddrs[0] = o;
1159     ifaddrs[1] = h;
1160     return 1;
1161 }
1162 
1163 /*
1164  * cifaddr - Clear the interface IP addresses, and delete routes
1165  * through the interface if possible.
1166  */
1167 int
1168 cifaddr(u, o, h)
1169     int u;
1170     u_int32_t o, h;
1171 {
1172     struct ifaliasreq ifra;
1173 
1174     ifaddrs[0] = 0;
1175     strlcpy(ifra.ifra_name, ifname, sizeof(ifra.ifra_name));
1176     SET_SA_FAMILY(ifra.ifra_addr, AF_INET);
1177     ((struct sockaddr_in *) &ifra.ifra_addr)->sin_addr.s_addr = o;
1178     SET_SA_FAMILY(ifra.ifra_broadaddr, AF_INET);
1179     ((struct sockaddr_in *) &ifra.ifra_broadaddr)->sin_addr.s_addr = h;
1180     BZERO(&ifra.ifra_mask, sizeof(ifra.ifra_mask));
1181     if (ioctl(sockfd, SIOCDIFADDR, (caddr_t) &ifra) < 0) {
1182 	if (errno != EADDRNOTAVAIL)
1183 	    syslog(LOG_WARNING, "Couldn't delete interface address: %m");
1184 	return 0;
1185     }
1186     return 1;
1187 }
1188 
1189 /*
1190  * sifdefaultroute - assign a default route through the address given.
1191  */
1192 int
1193 sifdefaultroute(u, l, g)
1194     int u;
1195     u_int32_t l, g;
1196 {
1197     return dodefaultroute(g, 's');
1198 }
1199 
1200 /*
1201  * cifdefaultroute - delete a default route through the address given.
1202  */
1203 int
1204 cifdefaultroute(u, l, g)
1205     int u;
1206     u_int32_t l, g;
1207 {
1208     return dodefaultroute(g, 'c');
1209 }
1210 
1211 /*
1212  * dodefaultroute - talk to a routing socket to add/delete a default route.
1213  */
1214 static int
1215 dodefaultroute(g, cmd)
1216     u_int32_t g;
1217     int cmd;
1218 {
1219     int routes;
1220     struct {
1221 	struct rt_msghdr	hdr;
1222 	struct sockaddr_in	dst;
1223 	struct sockaddr_in	gway;
1224 	struct sockaddr_in	mask;
1225     } rtmsg;
1226 
1227     if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
1228 	syslog(LOG_ERR, "Couldn't %s default route: socket: %m",
1229 	       cmd=='s'? "add": "delete");
1230 	return 0;
1231     }
1232 
1233     memset(&rtmsg, 0, sizeof(rtmsg));
1234     rtmsg.hdr.rtm_type = cmd == 's'? RTM_ADD: RTM_DELETE;
1235     rtmsg.hdr.rtm_flags = RTF_UP | RTF_GATEWAY;
1236     rtmsg.hdr.rtm_version = RTM_VERSION;
1237     rtmsg.hdr.rtm_seq = ++rtm_seq;
1238     rtmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
1239     rtmsg.dst.sin_len = sizeof(rtmsg.dst);
1240     rtmsg.dst.sin_family = AF_INET;
1241     rtmsg.gway.sin_len = sizeof(rtmsg.gway);
1242     rtmsg.gway.sin_family = AF_INET;
1243     rtmsg.gway.sin_addr.s_addr = g;
1244     rtmsg.mask.sin_len = sizeof(rtmsg.dst);
1245     rtmsg.mask.sin_family = AF_INET;
1246 
1247     rtmsg.hdr.rtm_msglen = sizeof(rtmsg);
1248     if (write(routes, &rtmsg, sizeof(rtmsg)) < 0) {
1249 	syslog(LOG_ERR, "Couldn't %s default route: %m",
1250 	       cmd=='s'? "add": "delete");
1251 	close(routes);
1252 	return 0;
1253     }
1254 
1255     close(routes);
1256     default_route_gateway = (cmd == 's')? g: 0;
1257     return 1;
1258 }
1259 
1260 #if RTM_VERSION >= 3
1261 
1262 /*
1263  * sifproxyarp - Make a proxy ARP entry for the peer.
1264  */
1265 static struct {
1266     struct rt_msghdr		hdr;
1267     struct sockaddr_inarp	dst;
1268     struct sockaddr_dl		hwa;
1269     char			extra[128];
1270 } arpmsg;
1271 
1272 static int arpmsg_valid;
1273 
1274 int
1275 sifproxyarp(unit, hisaddr)
1276     int unit;
1277     u_int32_t hisaddr;
1278 {
1279     int routes;
1280 
1281     /*
1282      * Get the hardware address of an interface on the same subnet
1283      * as our local address.
1284      */
1285     memset(&arpmsg, 0, sizeof(arpmsg));
1286     if (!get_ether_addr(hisaddr, &arpmsg.hwa)) {
1287 	syslog(LOG_ERR, "Cannot determine ethernet address for proxy ARP");
1288 	return 0;
1289     }
1290 
1291     if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
1292 	syslog(LOG_ERR, "Couldn't add proxy arp entry: socket: %m");
1293 	return 0;
1294     }
1295 
1296     arpmsg.hdr.rtm_type = RTM_ADD;
1297     arpmsg.hdr.rtm_flags = RTF_ANNOUNCE | RTF_HOST | RTF_STATIC;
1298     arpmsg.hdr.rtm_version = RTM_VERSION;
1299     arpmsg.hdr.rtm_seq = ++rtm_seq;
1300     arpmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY;
1301     arpmsg.hdr.rtm_inits = RTV_EXPIRE;
1302     arpmsg.dst.sin_len = sizeof(struct sockaddr_inarp);
1303     arpmsg.dst.sin_family = AF_INET;
1304     arpmsg.dst.sin_addr.s_addr = hisaddr;
1305     arpmsg.dst.sin_other = SIN_PROXY;
1306 
1307     arpmsg.hdr.rtm_msglen = (char *) &arpmsg.hwa - (char *) &arpmsg
1308 	+ arpmsg.hwa.sdl_len;
1309     if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
1310 	syslog(LOG_ERR, "Couldn't add proxy arp entry: %m");
1311 	close(routes);
1312 	return 0;
1313     }
1314 
1315     close(routes);
1316     arpmsg_valid = 1;
1317     proxy_arp_addr = hisaddr;
1318     return 1;
1319 }
1320 
1321 /*
1322  * cifproxyarp - Delete the proxy ARP entry for the peer.
1323  */
1324 int
1325 cifproxyarp(unit, hisaddr)
1326     int unit;
1327     u_int32_t hisaddr;
1328 {
1329     int routes;
1330 
1331     if (!arpmsg_valid)
1332 	return 0;
1333     arpmsg_valid = 0;
1334 
1335     arpmsg.hdr.rtm_type = RTM_DELETE;
1336     arpmsg.hdr.rtm_seq = ++rtm_seq;
1337 
1338     if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
1339 	syslog(LOG_ERR, "Couldn't delete proxy arp entry: socket: %m");
1340 	return 0;
1341     }
1342 
1343     if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
1344 	syslog(LOG_ERR, "Couldn't delete proxy arp entry: %m");
1345 	close(routes);
1346 	return 0;
1347     }
1348 
1349     close(routes);
1350     proxy_arp_addr = 0;
1351     return 1;
1352 }
1353 
1354 #else	/* RTM_VERSION */
1355 
1356 /*
1357  * sifproxyarp - Make a proxy ARP entry for the peer.
1358  */
1359 int
1360 sifproxyarp(unit, hisaddr)
1361     int unit;
1362     u_int32_t hisaddr;
1363 {
1364     struct arpreq arpreq;
1365     struct {
1366 	struct sockaddr_dl	sdl;
1367 	char			space[128];
1368     } dls;
1369 
1370     BZERO(&arpreq, sizeof(arpreq));
1371 
1372     /*
1373      * Get the hardware address of an interface on the same subnet
1374      * as our local address.
1375      */
1376     if (!get_ether_addr(hisaddr, &dls.sdl)) {
1377 	syslog(LOG_ERR, "Cannot determine ethernet address for proxy ARP");
1378 	return 0;
1379     }
1380 
1381     arpreq.arp_ha.sa_len = sizeof(struct sockaddr);
1382     arpreq.arp_ha.sa_family = AF_UNSPEC;
1383     BCOPY(LLADDR(&dls.sdl), arpreq.arp_ha.sa_data, dls.sdl.sdl_alen);
1384     SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
1385     ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = hisaddr;
1386     arpreq.arp_flags = ATF_PERM | ATF_PUBL;
1387     if (ioctl(sockfd, SIOCSARP, (caddr_t)&arpreq) < 0) {
1388 	syslog(LOG_ERR, "Couldn't add proxy arp entry: %m");
1389 	return 0;
1390     }
1391 
1392     proxy_arp_addr = hisaddr;
1393     return 1;
1394 }
1395 
1396 /*
1397  * cifproxyarp - Delete the proxy ARP entry for the peer.
1398  */
1399 int
1400 cifproxyarp(unit, hisaddr)
1401     int unit;
1402     u_int32_t hisaddr;
1403 {
1404     struct arpreq arpreq;
1405 
1406     BZERO(&arpreq, sizeof(arpreq));
1407     SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
1408     ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = hisaddr;
1409     if (ioctl(sockfd, SIOCDARP, (caddr_t)&arpreq) < 0) {
1410 	syslog(LOG_WARNING, "Couldn't delete proxy arp entry: %m");
1411 	return 0;
1412     }
1413     proxy_arp_addr = 0;
1414     return 1;
1415 }
1416 #endif	/* RTM_VERSION */
1417 
1418 
1419 /*
1420  * get_ether_addr - get the hardware address of an interface on the
1421  * the same subnet as ipaddr.
1422  */
1423 #define MAX_IFS		32
1424 
1425 static int
1426 get_ether_addr(ipaddr, hwaddr)
1427     u_int32_t ipaddr;
1428     struct sockaddr_dl *hwaddr;
1429 {
1430     struct ifreq *ifr, *ifend, *ifp;
1431     u_int32_t ina, mask;
1432     struct sockaddr_dl *dla;
1433     struct ifreq ifreq;
1434     struct ifconf ifc;
1435     struct ifreq ifs[MAX_IFS];
1436 
1437     ifc.ifc_len = sizeof(ifs);
1438     ifc.ifc_req = ifs;
1439     if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) {
1440 	syslog(LOG_ERR, "ioctl(SIOCGIFCONF): %m");
1441 	return 0;
1442     }
1443 
1444     /*
1445      * Scan through looking for an interface with an Internet
1446      * address on the same subnet as `ipaddr'.
1447      */
1448     ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
1449     for (ifr = ifc.ifc_req; ifr < ifend; ifr = (struct ifreq *)
1450 	 	((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len)) {
1451 	if (ifr->ifr_addr.sa_family == AF_INET) {
1452 	    ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
1453 	    strlcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
1454 	    /*
1455 	     * Check that the interface is up, and not point-to-point
1456 	     * or loopback.
1457 	     */
1458 	    if (ioctl(sockfd, SIOCGIFFLAGS, &ifreq) < 0)
1459 		continue;
1460 	    if ((ifreq.ifr_flags &
1461 		 (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|IFF_LOOPBACK|IFF_NOARP))
1462 		 != (IFF_UP|IFF_BROADCAST))
1463 		continue;
1464 	    /*
1465 	     * Get its netmask and check that it's on the right subnet.
1466 	     */
1467 	    ifreq.ifr_addr = ifr->ifr_addr;
1468 	    if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
1469 		continue;
1470 	    mask = ((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr;
1471 	    if ((ipaddr & mask) != (ina & mask))
1472 		continue;
1473 
1474 	    break;
1475 	}
1476     }
1477 
1478     if (ifr >= ifend)
1479 	return 0;
1480     syslog(LOG_INFO, "found interface %s for proxy arp", ifr->ifr_name);
1481 
1482     /*
1483      * Now scan through again looking for a link-level address
1484      * for this interface.
1485      */
1486     ifp = ifr;
1487     for (ifr = ifc.ifc_req; ifr < ifend; ) {
1488 	if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0
1489 	    && ifr->ifr_addr.sa_family == AF_LINK) {
1490 	    /*
1491 	     * Found the link-level address - copy it out
1492 	     */
1493 	    dla = (struct sockaddr_dl *) &ifr->ifr_addr;
1494 	    BCOPY(dla, hwaddr, dla->sdl_len);
1495 	    return 1;
1496 	}
1497 	ifr = (struct ifreq *) ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
1498     }
1499 
1500     return 0;
1501 }
1502 
1503 /*
1504  * Return user specified netmask, modified by any mask we might determine
1505  * for address `addr' (in network byte order).
1506  * Here we scan through the system's list of interfaces, looking for
1507  * any non-point-to-point interfaces which might appear to be on the same
1508  * network as `addr'.  If we find any, we OR in their netmask to the
1509  * user-specified netmask.
1510  */
1511 u_int32_t
1512 GetMask(addr)
1513     u_int32_t addr;
1514 {
1515     u_int32_t mask, nmask, ina;
1516     struct ifreq *ifr, *ifend, ifreq;
1517     struct ifconf ifc;
1518     struct ifreq ifs[MAX_IFS];
1519 
1520     addr = ntohl(addr);
1521     if (IN_CLASSA(addr))	/* determine network mask for address class */
1522 	nmask = IN_CLASSA_NET;
1523     else if (IN_CLASSB(addr))
1524 	nmask = IN_CLASSB_NET;
1525     else
1526 	nmask = IN_CLASSC_NET;
1527     /* class D nets are disallowed by bad_ip_adrs */
1528     mask = netmask | htonl(nmask);
1529 
1530     /*
1531      * Scan through the system's network interfaces.
1532      */
1533     ifc.ifc_len = sizeof(ifs);
1534     ifc.ifc_req = ifs;
1535     if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) {
1536 	syslog(LOG_WARNING, "ioctl(SIOCGIFCONF): %m");
1537 	return mask;
1538     }
1539     ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
1540     for (ifr = ifc.ifc_req; ifr < ifend; ifr = (struct ifreq *)
1541 	 	((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len)) {
1542 	/*
1543 	 * Check the interface's internet address.
1544 	 */
1545 	if (ifr->ifr_addr.sa_family != AF_INET)
1546 	    continue;
1547 	ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
1548 	if ((ntohl(ina) & nmask) != (addr & nmask))
1549 	    continue;
1550 	/*
1551 	 * Check that the interface is up, and not point-to-point or loopback.
1552 	 */
1553 	strlcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
1554 	if (ioctl(sockfd, SIOCGIFFLAGS, &ifreq) < 0)
1555 	    continue;
1556 	if ((ifreq.ifr_flags & (IFF_UP|IFF_POINTOPOINT|IFF_LOOPBACK))
1557 	    != IFF_UP)
1558 	    continue;
1559 	/*
1560 	 * Get its netmask and OR it into our mask.
1561 	 */
1562 	ifreq.ifr_addr = ifr->ifr_addr;
1563 	if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
1564 	    continue;
1565 	mask |= ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr.s_addr;
1566     }
1567 
1568     return mask;
1569 }
1570 
1571 /*
1572  * Use the hostid as part of the random number seed.
1573  */
1574 int
1575 get_host_seed()
1576 {
1577     return gethostid();
1578 }
1579 
1580 /*
1581  * lock - create a lock file for the named lock device
1582  */
1583 #define	LOCK_PREFIX	"/var/spool/lock/LCK.."
1584 
1585 int
1586 lock(dev)
1587     char *dev;
1588 {
1589     char hdb_lock_buffer[12];
1590     int fd, n;
1591     pid_t pid;
1592     char *p;
1593 
1594     if ((p = strrchr(dev, '/')) != NULL)
1595 	dev = p + 1;
1596     if (asprintf(&lock_file, "%s%s", LOCK_PREFIX, dev) == -1)
1597 	novm("lock file name");
1598 
1599     while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
1600 	if (errno == EEXIST
1601 	    && (fd = open(lock_file, O_RDONLY, 0)) >= 0) {
1602 	    /* Read the lock file to find out who has the device locked */
1603 	    n = read(fd, hdb_lock_buffer, 11);
1604 	    if (n <= 0) {
1605 		syslog(LOG_ERR, "Can't read pid from lock file %s", lock_file);
1606 		close(fd);
1607 	    } else {
1608 		hdb_lock_buffer[n] = 0;
1609 		pid = atoi(hdb_lock_buffer);
1610 		if (kill(pid, 0) == -1 && errno == ESRCH) {
1611 		    /* pid no longer exists - remove the lock file */
1612 		    if (unlink(lock_file) == 0) {
1613 			close(fd);
1614 			syslog(LOG_NOTICE, "Removed stale lock on %s (pid %ld)",
1615 			       dev, (long)pid);
1616 			continue;
1617 		    } else
1618 			syslog(LOG_WARNING, "Couldn't remove stale lock on %s",
1619 			       dev);
1620 		} else
1621 		    syslog(LOG_NOTICE, "Device %s is locked by pid %ld",
1622 			   dev, (long)pid);
1623 	    }
1624 	    close(fd);
1625 	} else
1626 	    syslog(LOG_ERR, "Can't create lock file %s: %m", lock_file);
1627 	free(lock_file);
1628 	lock_file = NULL;
1629 	return -1;
1630     }
1631 
1632     snprintf(hdb_lock_buffer, sizeof hdb_lock_buffer, "%10ld\n", (long)getpid());
1633     write(fd, hdb_lock_buffer, 11);
1634 
1635     close(fd);
1636     return 0;
1637 }
1638 
1639 /*
1640  * unlock - remove our lockfile
1641  */
1642 void
1643 unlock()
1644 {
1645     if (lock_file) {
1646 	unlink(lock_file);
1647 	free(lock_file);
1648 	lock_file = NULL;
1649     }
1650 }
1651