673 lines
16 KiB
C
673 lines
16 KiB
C
/*
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* sys-bsd.c - System-dependent procedures for setting up
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* PPP interfaces on bsd-4.4-ish systems (including 386BSD, NetBSD, etc.)
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*
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* Copyright (c) 1989 Carnegie Mellon University.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by Carnegie Mellon University. The name of the
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* University may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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#ifndef lint
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static char rcsid[] = "$Id: sys-bsd.c,v 1.5 1994/05/30 00:45:15 paulus Exp $";
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#endif
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/*
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* TODO:
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*/
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#include <syslog.h>
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#include <sys/ioctl.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <sys/errno.h>
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#include <net/if.h>
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#include <net/if_ppp.h>
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#include <net/route.h>
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#include <net/if_dl.h>
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#include <netinet/in.h>
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#include <netinet/if_ether.h>
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#include "pppd.h"
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#include "ppp.h"
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static int initdisc = -1; /* Initial TTY discipline */
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extern int kdebugflag;
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int rtm_seq;
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/*
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* establish_ppp - Turn the serial port into a ppp interface.
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*/
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void
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establish_ppp()
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{
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int pppdisc = PPPDISC;
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int x;
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if (ioctl(fd, TIOCGETD, &initdisc) < 0) {
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syslog(LOG_ERR, "ioctl(TIOCGETD): %m");
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die(1);
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}
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if (ioctl(fd, TIOCSETD, &pppdisc) < 0) {
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syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
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die(1);
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}
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/*
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* Find out which interface we were given.
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*/
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if (ioctl(fd, PPPIOCGUNIT, &ifunit) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCGUNIT): %m");
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die(1);
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}
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/*
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* Enable debug in the driver if requested.
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*/
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if (kdebugflag) {
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_WARNING, "ioctl (PPPIOCGFLAGS): %m");
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} else {
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x |= (kdebugflag & 0xFF) * SC_DEBUG;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0)
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syslog(LOG_WARNING, "ioctl(PPPIOCSFLAGS): %m");
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}
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}
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}
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/*
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* disestablish_ppp - Restore the serial port to normal operation.
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* This shouldn't call die() because it's called from die().
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*/
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void
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disestablish_ppp()
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{
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int x;
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char *s;
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if (initdisc >= 0) {
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/*
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* Check whether the link seems not to be 8-bit clean.
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*/
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) == 0) {
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s = NULL;
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switch (~x & (SC_RCV_B7_0|SC_RCV_B7_1|SC_RCV_EVNP|SC_RCV_ODDP)) {
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case SC_RCV_B7_0:
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s = "bit 7 set to 1";
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break;
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case SC_RCV_B7_1:
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s = "bit 7 set to 0";
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break;
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case SC_RCV_EVNP:
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s = "odd parity";
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break;
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case SC_RCV_ODDP:
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s = "even parity";
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break;
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}
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if (s != NULL) {
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syslog(LOG_WARNING, "Serial link is not 8-bit clean:");
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syslog(LOG_WARNING, "All received characters had %s", s);
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}
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}
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if (ioctl(fd, TIOCSETD, &initdisc) < 0)
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syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
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}
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}
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/*
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* output - Output PPP packet.
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*/
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void
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output(unit, p, len)
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int unit;
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u_char *p;
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int len;
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{
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if (unit != 0)
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MAINDEBUG((LOG_WARNING, "output: unit != 0!"));
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if (debug)
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log_packet(p, len, "sent ");
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if (write(fd, p, len) < 0) {
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syslog(LOG_ERR, "write: %m");
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die(1);
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}
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}
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/*
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* read_packet - get a PPP packet from the serial device.
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*/
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int
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read_packet(buf)
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u_char *buf;
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{
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int len;
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if ((len = read(fd, buf, MTU + DLLHEADERLEN)) < 0) {
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if (errno == EWOULDBLOCK) {
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MAINDEBUG((LOG_DEBUG, "read(fd): EWOULDBLOCK"));
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return -1;
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}
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syslog(LOG_ERR, "read(fd): %m");
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die(1);
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}
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return len;
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}
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/*
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* ppp_send_config - configure the transmit characteristics of
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* the ppp interface.
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*/
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void
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ppp_send_config(unit, mtu, asyncmap, pcomp, accomp)
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int unit, mtu;
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u_long asyncmap;
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int pcomp, accomp;
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{
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u_int x;
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struct ifreq ifr;
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strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
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ifr.ifr_mtu = mtu;
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if (ioctl(s, SIOCSIFMTU, (caddr_t) &ifr) < 0) {
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syslog(LOG_ERR, "ioctl(SIOCSIFMTU): %m");
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quit();
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}
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if (ioctl(fd, PPPIOCSASYNCMAP, (caddr_t) &asyncmap) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSASYNCMAP): %m");
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quit();
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}
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
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quit();
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}
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x = pcomp? x | SC_COMP_PROT: x &~ SC_COMP_PROT;
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x = accomp? x | SC_COMP_AC: x &~ SC_COMP_AC;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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quit();
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}
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}
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/*
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* ppp_set_xaccm - set the extended transmit ACCM for the interface.
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*/
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void
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ppp_set_xaccm(unit, accm)
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int unit;
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ext_accm accm;
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{
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if (ioctl(fd, PPPIOCSXASYNCMAP, accm) < 0 && errno != ENOTTY)
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syslog(LOG_WARNING, "ioctl(set extended ACCM): %m");
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}
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/*
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* ppp_recv_config - configure the receive-side characteristics of
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* the ppp interface.
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*/
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void
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ppp_recv_config(unit, mru, asyncmap, pcomp, accomp)
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int unit, mru;
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u_long asyncmap;
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int pcomp, accomp;
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{
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int x;
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if (ioctl(fd, PPPIOCSMRU, (caddr_t) &mru) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSMRU): %m");
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quit();
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}
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if (ioctl(fd, PPPIOCSRASYNCMAP, (caddr_t) &asyncmap) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSRASYNCMAP): %m");
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quit();
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}
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
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quit();
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}
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x = !accomp? x | SC_REJ_COMP_AC: x &~ SC_REJ_COMP_AC;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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quit();
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}
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}
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/*
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* sifvjcomp - config tcp header compression
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*/
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int
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sifvjcomp(u, vjcomp, cidcomp, maxcid)
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int u, vjcomp, cidcomp, maxcid;
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{
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u_int x;
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
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return 0;
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}
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x = vjcomp ? x | SC_COMP_TCP: x &~ SC_COMP_TCP;
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x = cidcomp? x & ~SC_NO_TCP_CCID: x | SC_NO_TCP_CCID;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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return 0;
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}
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if (ioctl(fd, PPPIOCSMAXCID, (caddr_t) &maxcid) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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return 0;
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}
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return 1;
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}
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/*
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* sifup - Config the interface up and enable IP packets to pass.
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*/
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int
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sifup(u)
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int u;
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{
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struct ifreq ifr;
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u_int x;
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strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
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if (ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) {
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syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
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return 0;
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}
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ifr.ifr_flags |= IFF_UP;
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if (ioctl(s, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) {
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syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m");
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return 0;
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}
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
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return 0;
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}
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x |= SC_ENABLE_IP;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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return 0;
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}
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return 1;
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}
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/*
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* sifdown - Config the interface down and disable IP.
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*/
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int
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sifdown(u)
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int u;
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{
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struct ifreq ifr;
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u_int x;
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int rv;
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rv = 1;
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if (ioctl(fd, PPPIOCGFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl (PPPIOCGFLAGS): %m");
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rv = 0;
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} else {
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x &= ~SC_ENABLE_IP;
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if (ioctl(fd, PPPIOCSFLAGS, (caddr_t) &x) < 0) {
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syslog(LOG_ERR, "ioctl(PPPIOCSFLAGS): %m");
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rv = 0;
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}
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}
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strncpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
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if (ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) < 0) {
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syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
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rv = 0;
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} else {
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ifr.ifr_flags &= ~IFF_UP;
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if (ioctl(s, SIOCSIFFLAGS, (caddr_t) &ifr) < 0) {
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syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m");
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rv = 0;
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}
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}
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return rv;
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}
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/*
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* SET_SA_FAMILY - set the sa_family field of a struct sockaddr,
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* if it exists.
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*/
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#define SET_SA_FAMILY(addr, family) \
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BZERO((char *) &(addr), sizeof(addr)); \
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addr.sa_family = (family); \
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addr.sa_len = sizeof(addr);
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/*
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* sifaddr - Config the interface IP addresses and netmask.
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*/
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int
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sifaddr(u, o, h, m)
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int u;
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u_long o, h, m;
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{
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struct ifaliasreq ifra;
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strncpy(ifra.ifra_name, ifname, sizeof(ifra.ifra_name));
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SET_SA_FAMILY(ifra.ifra_addr, AF_INET);
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((struct sockaddr_in *) &ifra.ifra_addr)->sin_addr.s_addr = o;
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SET_SA_FAMILY(ifra.ifra_broadaddr, AF_INET);
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((struct sockaddr_in *) &ifra.ifra_broadaddr)->sin_addr.s_addr = h;
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if (m != 0) {
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SET_SA_FAMILY(ifra.ifra_mask, AF_INET);
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((struct sockaddr_in *) &ifra.ifra_mask)->sin_addr.s_addr = m;
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} else
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BZERO(&ifra.ifra_mask, sizeof(ifra.ifra_mask));
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if (ioctl(s, SIOCAIFADDR, (caddr_t) &ifra) < 0) {
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if (errno != EEXIST) {
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syslog(LOG_ERR, "ioctl(SIOCAIFADDR): %m");
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return 0;
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}
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syslog(LOG_WARNING, "ioctl(SIOCAIFADDR): Address already exists");
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}
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return 1;
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}
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/*
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* cifaddr - Clear the interface IP addresses, and delete routes
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* through the interface if possible.
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*/
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int
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cifaddr(u, o, h)
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int u;
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u_long o, h;
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{
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struct ifaliasreq ifra;
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strncpy(ifra.ifra_name, ifname, sizeof(ifra.ifra_name));
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SET_SA_FAMILY(ifra.ifra_addr, AF_INET);
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((struct sockaddr_in *) &ifra.ifra_addr)->sin_addr.s_addr = o;
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SET_SA_FAMILY(ifra.ifra_broadaddr, AF_INET);
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((struct sockaddr_in *) &ifra.ifra_broadaddr)->sin_addr.s_addr = h;
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BZERO(&ifra.ifra_mask, sizeof(ifra.ifra_mask));
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if (ioctl(s, SIOCDIFADDR, (caddr_t) &ifra) < 0) {
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syslog(LOG_WARNING, "ioctl(SIOCDIFADDR): %m");
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return 0;
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}
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return 1;
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}
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/*
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* sifdefaultroute - assign a default route through the address given.
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*/
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int
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sifdefaultroute(u, g)
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int u;
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u_long g;
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{
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return dodefaultroute(g, 's');
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}
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/*
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* cifdefaultroute - delete a default route through the address given.
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*/
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int
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cifdefaultroute(u, g)
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int u;
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u_long g;
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{
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return dodefaultroute(g, 'c');
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}
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int
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dodefaultroute(g, cmd)
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u_long g;
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int cmd;
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{
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int routes;
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struct {
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struct rt_msghdr hdr;
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struct sockaddr_in dst;
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struct sockaddr_in gway;
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struct sockaddr_in mask;
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} rtmsg;
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if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
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syslog(LOG_ERR, "%cifdefaultroute: opening routing socket: %m", cmd);
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return 0;
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}
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memset(&rtmsg, 0, sizeof(rtmsg));
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rtmsg.hdr.rtm_type = cmd == 's'? RTM_ADD: RTM_DELETE;
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rtmsg.hdr.rtm_flags = RTF_UP | RTF_GATEWAY;
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rtmsg.hdr.rtm_version = RTM_VERSION;
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rtmsg.hdr.rtm_seq = ++rtm_seq;
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rtmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
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rtmsg.dst.sin_len = sizeof(rtmsg.dst);
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rtmsg.dst.sin_family = AF_INET;
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rtmsg.gway.sin_len = sizeof(rtmsg.gway);
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rtmsg.gway.sin_family = AF_INET;
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rtmsg.gway.sin_addr.s_addr = g;
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rtmsg.mask.sin_len = sizeof(rtmsg.dst);
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rtmsg.mask.sin_family = AF_INET;
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rtmsg.hdr.rtm_msglen = sizeof(rtmsg);
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if (write(routes, &rtmsg, sizeof(rtmsg)) < 0) {
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syslog(LOG_ERR, "%s default route: %m", cmd=='s'? "add": "delete");
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close(routes);
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return 0;
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}
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close(routes);
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return 1;
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}
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/*
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* sifproxyarp - Make a proxy ARP entry for the peer.
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*/
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static struct {
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struct rt_msghdr hdr;
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struct sockaddr_inarp dst;
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struct sockaddr_dl hwa;
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char extra[128];
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} arpmsg;
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static int arpmsg_valid;
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int
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sifproxyarp(unit, hisaddr)
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int unit;
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u_long hisaddr;
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{
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int routes;
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int l;
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/*
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* Get the hardware address of an interface on the same subnet
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* as our local address.
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*/
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memset(&arpmsg, 0, sizeof(arpmsg));
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if (!get_ether_addr(hisaddr, &arpmsg.hwa)) {
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syslog(LOG_ERR, "Cannot determine ethernet address for proxy ARP");
|
|
return 0;
|
|
}
|
|
|
|
if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
|
|
syslog(LOG_ERR, "sifproxyarp: opening routing socket: %m");
|
|
return 0;
|
|
}
|
|
|
|
arpmsg.hdr.rtm_type = RTM_ADD;
|
|
arpmsg.hdr.rtm_flags = RTF_ANNOUNCE | RTF_HOST | RTF_STATIC;
|
|
arpmsg.hdr.rtm_version = RTM_VERSION;
|
|
arpmsg.hdr.rtm_seq = ++rtm_seq;
|
|
arpmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY;
|
|
arpmsg.hdr.rtm_inits = RTV_EXPIRE;
|
|
arpmsg.dst.sin_len = sizeof(struct sockaddr_inarp);
|
|
arpmsg.dst.sin_family = AF_INET;
|
|
arpmsg.dst.sin_addr.s_addr = hisaddr;
|
|
arpmsg.dst.sin_other = SIN_PROXY;
|
|
|
|
arpmsg.hdr.rtm_msglen = (char *) &arpmsg.hwa - (char *) &arpmsg
|
|
+ arpmsg.hwa.sdl_len;
|
|
if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
|
|
syslog(LOG_ERR, "add proxy arp entry: %m");
|
|
close(routes);
|
|
return 0;
|
|
}
|
|
|
|
close(routes);
|
|
arpmsg_valid = 1;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* cifproxyarp - Delete the proxy ARP entry for the peer.
|
|
*/
|
|
int
|
|
cifproxyarp(unit, hisaddr)
|
|
int unit;
|
|
u_long hisaddr;
|
|
{
|
|
int routes;
|
|
|
|
if (!arpmsg_valid)
|
|
return 0;
|
|
arpmsg_valid = 0;
|
|
|
|
arpmsg.hdr.rtm_type = RTM_DELETE;
|
|
arpmsg.hdr.rtm_seq = ++rtm_seq;
|
|
|
|
if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
|
|
syslog(LOG_ERR, "sifproxyarp: opening routing socket: %m");
|
|
return 0;
|
|
}
|
|
|
|
if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
|
|
syslog(LOG_ERR, "delete proxy arp entry: %m");
|
|
close(routes);
|
|
return 0;
|
|
}
|
|
|
|
close(routes);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* get_ether_addr - get the hardware address of an interface on the
|
|
* the same subnet as ipaddr.
|
|
*/
|
|
#define MAX_IFS 32
|
|
|
|
int
|
|
get_ether_addr(ipaddr, hwaddr)
|
|
u_long ipaddr;
|
|
struct sockaddr_dl *hwaddr;
|
|
{
|
|
struct ifreq *ifr, *ifend, *ifp;
|
|
u_long ina, mask;
|
|
struct sockaddr_dl *dla;
|
|
struct ifreq ifreq;
|
|
struct ifconf ifc;
|
|
struct ifreq ifs[MAX_IFS];
|
|
|
|
ifc.ifc_len = sizeof(ifs);
|
|
ifc.ifc_req = ifs;
|
|
if (ioctl(s, SIOCGIFCONF, &ifc) < 0) {
|
|
syslog(LOG_ERR, "ioctl(SIOCGIFCONF): %m");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Scan through looking for an interface with an Internet
|
|
* address on the same subnet as `ipaddr'.
|
|
*/
|
|
ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
|
|
for (ifr = ifc.ifc_req; ifr < ifend; ) {
|
|
if (ifr->ifr_addr.sa_family == AF_INET) {
|
|
ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
|
|
strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
|
|
/*
|
|
* Check that the interface is up, and not point-to-point
|
|
* or loopback.
|
|
*/
|
|
if (ioctl(s, SIOCGIFFLAGS, &ifreq) < 0)
|
|
continue;
|
|
if ((ifreq.ifr_flags &
|
|
(IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|IFF_LOOPBACK|IFF_NOARP))
|
|
!= (IFF_UP|IFF_BROADCAST))
|
|
continue;
|
|
/*
|
|
* Get its netmask and check that it's on the right subnet.
|
|
*/
|
|
if (ioctl(s, SIOCGIFNETMASK, &ifreq) < 0)
|
|
continue;
|
|
mask = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
|
|
if ((ipaddr & mask) != (ina & mask))
|
|
continue;
|
|
|
|
break;
|
|
}
|
|
ifr = (struct ifreq *) ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
|
|
}
|
|
|
|
if (ifr >= ifend)
|
|
return 0;
|
|
syslog(LOG_INFO, "found interface %s for proxy arp", ifr->ifr_name);
|
|
|
|
/*
|
|
* Now scan through again looking for a link-level address
|
|
* for this interface.
|
|
*/
|
|
ifp = ifr;
|
|
for (ifr = ifc.ifc_req; ifr < ifend; ) {
|
|
if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0
|
|
&& ifr->ifr_addr.sa_family == AF_LINK) {
|
|
/*
|
|
* Found the link-level address - copy it out
|
|
*/
|
|
dla = (struct sockaddr_dl *) &ifr->ifr_addr;
|
|
BCOPY(dla, hwaddr, dla->sdl_len);
|
|
return 1;
|
|
}
|
|
ifr = (struct ifreq *) ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* ppp_available - check whether the system has any ppp interfaces
|
|
* (in fact we check whether we can do an ioctl on ppp0).
|
|
*/
|
|
int
|
|
ppp_available()
|
|
{
|
|
int s, ok;
|
|
struct ifreq ifr;
|
|
|
|
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
|
|
return 1; /* can't tell - maybe we're not root */
|
|
|
|
strncpy(ifr.ifr_name, "ppp0", sizeof (ifr.ifr_name));
|
|
ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0;
|
|
close(s);
|
|
|
|
return ok;
|
|
}
|