+ * remove_fd - remove an fd from the set that wait_input waits for.
+ */
+void remove_fd(int fd)
+{
+ FD_CLR(fd, &in_fds);
+}
+
+#if 0
+/********************************************************************
+ *
+ * wait_loop_output - wait until there is data available on the
+ * loopback, for the length of time specified by *timo (indefinite
+ * if timo is NULL).
+ */
+void wait_loop_output(timo)
+ struct timeval *timo;
+{
+ fd_set ready;
+ int n;
+
+ FD_ZERO(&ready);
+ FD_SET(master_fd, &ready);
+ n = select(master_fd + 1, &ready, NULL, &ready, timo);
+ if (n < 0 && errno != EINTR)
+ fatal("select: %m(%d)", errno);
+}
+
+/********************************************************************
+ *
+ * wait_time - wait for a given length of time or until a
+ * signal is received.
+ */
+
+void wait_time(timo)
+ struct timeval *timo;
+{
+ int n;
+
+ n = select(0, NULL, NULL, NULL, timo);
+ if (n < 0 && errno != EINTR)
+ fatal("select: %m(%d)", errno);
+}
+#endif
+
+/********************************************************************
+ *
+ * read_packet - get a PPP packet from the serial device.
+ */
+
+int read_packet (unsigned char *buf)
+{
+ int len;
+
+ len = read(ppp_fd, buf, PPP_MTU + PPP_HDRLEN);
+ if (len < 0) {
+ if (errno == EWOULDBLOCK || errno == EIO)
+ return -1;
+ fatal("read: %m(%d)", errno);
+ }
+ return len;
+}
+
+/********************************************************************
+ *
+ * get_loop_output - get outgoing packets from the ppp device,
+ * and detect when we want to bring the real link up.
+ * Return value is 1 if we need to bring up the link, 0 otherwise.
+ */
+int
+get_loop_output(void)
+{
+ int rv = 0;
+ int n = read(master_fd, inbuf, sizeof(inbuf));
+
+ while (n > 0) {
+ if (loop_chars(inbuf, n))
+ rv = 1;
+ n = read(master_fd, inbuf, sizeof(inbuf));
+ }
+
+ if (n == 0)
+ fatal("eof on loopback");
+
+ if (errno != EWOULDBLOCK)
+ fatal("read from loopback: %m(%d)", errno);
+
+ return rv;
+}
+
+/********************************************************************
+ *
+ * ppp_send_config - configure the transmit characteristics of
+ * the ppp interface.
+ */
+
+void ppp_send_config (int unit,int mtu,u_int32_t asyncmap,int pcomp,int accomp)
+{
+ u_int x;
+ struct ifreq ifr;
+
+ SYSDEBUG ((LOG_DEBUG, "send_config: mtu = %d\n", mtu));
+/*
+ * Ensure that the link is still up.
+ */
+ if (!still_ppp())
+ return;
+/*
+ * Set the MTU and other parameters for the ppp device
+ */
+ memset (&ifr, '\0', sizeof (ifr));
+ strlcpy(ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
+ ifr.ifr_mtu = mtu;
+
+ if (ioctl(sock_fd, SIOCSIFMTU, (caddr_t) &ifr) < 0)
+ fatal("ioctl(SIOCSIFMTU): %m(%d)", errno);
+
+ SYSDEBUG ((LOG_DEBUG, "send_config: asyncmap = %lx\n", asyncmap));
+ if (ioctl(ppp_fd, PPPIOCSASYNCMAP, (caddr_t) &asyncmap) < 0) {
+ if (!ok_error(errno))
+ fatal("ioctl(PPPIOCSASYNCMAP): %m(%d)", errno);
+ return;
+ }
+
+ x = get_flags();
+ x = pcomp ? x | SC_COMP_PROT : x & ~SC_COMP_PROT;
+ x = accomp ? x | SC_COMP_AC : x & ~SC_COMP_AC;
+ x = sync_serial ? x | SC_SYNC : x & ~SC_SYNC;
+ set_flags(x);
+}
+
+/********************************************************************
+ *
+ * ppp_set_xaccm - set the extended transmit ACCM for the interface.
+ */
+
+void ppp_set_xaccm (int unit, ext_accm accm)
+{
+ SYSDEBUG ((LOG_DEBUG, "set_xaccm: %08lx %08lx %08lx %08lx\n",
+ accm[0], accm[1], accm[2], accm[3]));
+
+ if (ioctl(ppp_fd, PPPIOCSXASYNCMAP, accm) < 0 && errno != ENOTTY) {
+ if ( ! ok_error (errno))
+ warn("ioctl(set extended ACCM): %m(%d)", errno);
+ }
+}
+
+/********************************************************************
+ *
+ * ppp_recv_config - configure the receive-side characteristics of
+ * the ppp interface.
+ */
+
+void ppp_recv_config (int unit,int mru,u_int32_t asyncmap,int pcomp,int accomp)
+{
+ u_int x;
+
+ SYSDEBUG ((LOG_DEBUG, "recv_config: mru = %d\n", mru));
+/*
+ * If we were called because the link has gone down then there is nothing
+ * which may be done. Just return without incident.
+ */
+ if (!still_ppp())
+ return;
+/*
+ * Set the receiver parameters
+ */
+ if (ioctl(ppp_fd, PPPIOCSMRU, (caddr_t) &mru) < 0) {
+ if ( ! ok_error (errno))
+ error("ioctl(PPPIOCSMRU): %m(%d)", errno);
+ }
+
+ SYSDEBUG ((LOG_DEBUG, "recv_config: asyncmap = %lx\n", asyncmap));
+ if (ioctl(ppp_fd, PPPIOCSRASYNCMAP, (caddr_t) &asyncmap) < 0) {
+ if (!ok_error(errno))
+ error("ioctl(PPPIOCSRASYNCMAP): %m(%d)", errno);
+ }
+
+ x = get_flags();
+ x = !accomp? x | SC_REJ_COMP_AC: x &~ SC_REJ_COMP_AC;
+ set_flags (x);
+}
+
+/********************************************************************
+ *
+ * ccp_test - ask kernel whether a given compression method
+ * is acceptable for use.
+ */
+
+int ccp_test (int unit, u_char *opt_ptr, int opt_len, int for_transmit)
+{
+ struct ppp_option_data data;
+
+ memset (&data, '\0', sizeof (data));
+ data.ptr = opt_ptr;
+ data.length = opt_len;
+ data.transmit = for_transmit;
+
+ if (ioctl(ppp_fd, PPPIOCSCOMPRESS, (caddr_t) &data) >= 0)
+ return 1;
+
+ return (errno == ENOBUFS)? 0: -1;
+}
+
+/********************************************************************
+ *
+ * ccp_flags_set - inform kernel about the current state of CCP.
+ */
+
+void ccp_flags_set (int unit, int isopen, int isup)
+{
+ if (still_ppp()) {
+ int x = get_flags();
+ x = isopen? x | SC_CCP_OPEN : x &~ SC_CCP_OPEN;
+ x = isup? x | SC_CCP_UP : x &~ SC_CCP_UP;
+ set_flags (x);
+ }
+}
+
+/********************************************************************
+ *
+ * get_idle_time - return how long the link has been idle.
+ */
+int
+get_idle_time(u, ip)
+ int u;
+ struct ppp_idle *ip;
+{
+ return ioctl(ppp_fd, PPPIOCGIDLE, ip) >= 0;
+}
+
+/********************************************************************
+ *
+ * get_ppp_stats - return statistics for the link.
+ */
+int
+get_ppp_stats(u, stats)
+ int u;
+ struct pppd_stats *stats;
+{
+ struct ifpppstatsreq req;
+
+ memset (&req, 0, sizeof (req));
+
+ req.stats_ptr = (caddr_t) &req.stats;
+ strlcpy(req.ifr__name, ifname, sizeof(req.ifr__name));
+ if (ioctl(sock_fd, SIOCGPPPSTATS, &req) < 0) {
+ error("Couldn't get PPP statistics: %m");
+ return 0;
+ }
+ stats->bytes_in = req.stats.p.ppp_ibytes;
+ stats->bytes_out = req.stats.p.ppp_obytes;
+ return 1;
+}
+
+/********************************************************************
+ *
+ * ccp_fatal_error - returns 1 if decompression was disabled as a
+ * result of an error detected after decompression of a packet,
+ * 0 otherwise. This is necessary because of patent nonsense.
+ */
+
+int ccp_fatal_error (int unit)
+{
+ int x = get_flags();
+
+ return x & SC_DC_FERROR;
+}
+
+/*
+ * path_to_route - determine the path to the proc file system data
+ */
+#define ROUTE_MAX_COLS 12
+FILE *route_fd = (FILE *) 0;
+static char route_buffer [512];
+static int route_dev_col, route_dest_col, route_gw_col;
+static int route_flags_col, route_mask_col;
+static int route_num_cols;
+
+static char *path_to_route (void);
+static int open_route_table (void);
+static void close_route_table (void);
+static int read_route_table (struct rtentry *rt);
+
+/********************************************************************
+ *
+ * path_to_procfs - find the path to the proc file system mount point
+ */
+
+static int path_to_procfs (void)
+{
+ struct mntent *mntent;
+ FILE *fp;
+
+ fp = fopen(MOUNTED, "r");
+ if (fp == NULL) {
+ /* Default the mount location of /proc */
+ strlcpy (route_buffer, "/proc", sizeof (route_buffer));
+ return 1;
+ }
+
+ while ((mntent = getmntent(fp)) != NULL) {
+ if (strcmp(mntent->mnt_type, MNTTYPE_IGNORE) == 0)
+ continue;
+ if (strcmp(mntent->mnt_type, "proc") == 0)
+ break;
+ }
+ fclose (fp);
+ if (mntent == 0)
+ return 0;
+
+ strlcpy(route_buffer, mntent->mnt_dir, sizeof (route_buffer));
+ return 1;
+}
+
+/********************************************************************
+ *
+ * path_to_route - find the path to the route tables in the proc file system
+ */
+
+static char *path_to_route (void)
+{
+ if (!path_to_procfs()) {
+ error("proc file system not mounted");
+ return 0;
+ }
+ strlcat (route_buffer, "/net/route", sizeof(route_buffer));
+ return (route_buffer);
+}
+
+/********************************************************************
+ *
+ * close_route_table - close the interface to the route table
+ */
+
+static void close_route_table (void)
+{
+ if (route_fd != (FILE *) 0) {
+ fclose (route_fd);
+ route_fd = (FILE *) 0;
+ }
+}
+
+/********************************************************************
+ *
+ * open_route_table - open the interface to the route table
+ */
+static char route_delims[] = " \t\n";
+
+static int open_route_table (void)
+{
+ char *path;
+
+ close_route_table();
+
+ path = path_to_route();
+ if (path == NULL)
+ return 0;
+
+ route_fd = fopen (path, "r");
+ if (route_fd == NULL) {
+ error("can't open %s: %m (%d)", path, errno);
+ return 0;
+ }
+
+ route_dev_col = 0; /* default to usual columns */
+ route_dest_col = 1;
+ route_gw_col = 2;
+ route_flags_col = 3;
+ route_mask_col = 7;
+ route_num_cols = 8;
+
+ /* parse header line */
+ if (fgets(route_buffer, sizeof(route_buffer), route_fd) != 0) {
+ char *p = route_buffer, *q;
+ int col;
+ for (col = 0; col < ROUTE_MAX_COLS; ++col) {
+ int used = 1;
+ if ((q = strtok(p, route_delims)) == 0)
+ break;
+ if (strcasecmp(q, "iface") == 0)
+ route_dev_col = col;
+ else if (strcasecmp(q, "destination") == 0)
+ route_dest_col = col;
+ else if (strcasecmp(q, "gateway") == 0)
+ route_gw_col = col;
+ else if (strcasecmp(q, "flags") == 0)
+ route_flags_col = col;
+ else if (strcasecmp(q, "mask") == 0)
+ route_mask_col = col;
+ else
+ used = 0;
+ if (used && col >= route_num_cols)
+ route_num_cols = col + 1;
+ p = NULL;
+ }
+ }
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * read_route_table - read the next entry from the route table
+ */
+
+static int read_route_table(struct rtentry *rt)
+{
+ char *cols[ROUTE_MAX_COLS], *p;
+ int col;
+
+ memset (rt, '\0', sizeof (struct rtentry));
+
+ if (fgets (route_buffer, sizeof (route_buffer), route_fd) == (char *) 0)
+ return 0;
+
+ p = route_buffer;
+ for (col = 0; col < route_num_cols; ++col) {
+ cols[col] = strtok(p, route_delims);
+ if (cols[col] == NULL)
+ return 0; /* didn't get enough columns */
+ }
+
+ ((struct sockaddr_in *) &rt->rt_dst)->sin_addr.s_addr =
+ strtoul(cols[route_dest_col], NULL, 16);
+
+ ((struct sockaddr_in *) &rt->rt_gateway)->sin_addr.s_addr =
+ strtoul(cols[route_gw_col], NULL, 16);
+
+ ((struct sockaddr_in *) &rt->rt_genmask)->sin_addr.s_addr =
+ strtoul(cols[route_mask_col], NULL, 16);
+
+ rt->rt_flags = (short) strtoul(cols[route_flags_col], NULL, 16);
+ rt->rt_dev = cols[route_dev_col];
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * defaultroute_exists - determine if there is a default route
+ */
+
+static int defaultroute_exists (struct rtentry *rt)
+{
+ int result = 0;
+
+ if (!open_route_table())
+ return 0;
+
+ while (read_route_table(rt) != 0) {
+ if ((rt->rt_flags & RTF_UP) == 0)
+ continue;
+
+ if (((struct sockaddr_in *) (&rt->rt_dst))->sin_addr.s_addr == 0L) {
+ result = 1;
+ break;
+ }
+ }
+
+ close_route_table();
+ return result;
+}
+
+/*
+ * have_route_to - determine if the system has any route to
+ * a given IP address. `addr' is in network byte order.
+ * Return value is 1 if yes, 0 if no, -1 if don't know.
+ * For demand mode to work properly, we have to ignore routes
+ * through our own interface.
+ */
+int have_route_to(u_int32_t addr)
+{
+ struct rtentry rt;
+ int result = 0;
+
+ if (!open_route_table())
+ return -1; /* don't know */
+
+ while (read_route_table(&rt)) {
+ if ((rt.rt_flags & RTF_UP) == 0 || strcmp(rt.rt_dev, ifname) == 0)
+ continue;
+ if ((addr & ((struct sockaddr_in *)&rt.rt_genmask)->sin_addr.s_addr)
+ == ((struct sockaddr_in *)&rt.rt_dst)->sin_addr.s_addr) {
+ result = 1;
+ break;
+ }
+ }
+
+ close_route_table();
+ return result;
+}
+
+/********************************************************************
+ *
+ * sifdefaultroute - assign a default route through the address given.
+ */
+
+int sifdefaultroute (int unit, u_int32_t ouraddr, u_int32_t gateway)
+{
+ struct rtentry rt;
+
+ if (defaultroute_exists(&rt) && strcmp(rt.rt_dev, ifname) != 0) {
+ struct in_addr old_gateway =
+ ((struct sockaddr_in *) (&rt.rt_gateway))-> sin_addr;
+
+ if (old_gateway.s_addr != gateway)
+ error("not replacing existing default route to %s [%I]",
+ rt.rt_dev, old_gateway);
+ return 0;
+ }
+
+ memset (&rt, '\0', sizeof (rt));
+ SET_SA_FAMILY (rt.rt_dst, AF_INET);
+ SET_SA_FAMILY (rt.rt_gateway, AF_INET);
+
+ if (kernel_version > KVERSION(2,1,0)) {
+ SET_SA_FAMILY (rt.rt_genmask, AF_INET);
+ ((struct sockaddr_in *) &rt.rt_genmask)->sin_addr.s_addr = 0L;
+ }
+
+ ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = gateway;
+
+ rt.rt_flags = RTF_UP | RTF_GATEWAY | RTF_DEFAULT;
+ if (ioctl(sock_fd, SIOCADDRT, &rt) < 0) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCADDRT): %m(%d)", errno);
+ return 0;
+ }
+
+ default_route_gateway = gateway;
+ return 1;
+}
+
+/********************************************************************
+ *
+ * cifdefaultroute - delete a default route through the address given.
+ */
+
+int cifdefaultroute (int unit, u_int32_t ouraddr, u_int32_t gateway)
+{
+ struct rtentry rt;
+
+ default_route_gateway = 0;
+
+ memset (&rt, '\0', sizeof (rt));
+ SET_SA_FAMILY (rt.rt_dst, AF_INET);
+ SET_SA_FAMILY (rt.rt_gateway, AF_INET);
+
+ if (kernel_version > KVERSION(2,1,0)) {
+ SET_SA_FAMILY (rt.rt_genmask, AF_INET);
+ ((struct sockaddr_in *) &rt.rt_genmask)->sin_addr.s_addr = 0L;
+ }
+
+ ((struct sockaddr_in *) &rt.rt_gateway)->sin_addr.s_addr = gateway;
+
+ rt.rt_flags = RTF_UP | RTF_GATEWAY | RTF_DEFAULT;
+ if (ioctl(sock_fd, SIOCDELRT, &rt) < 0 && errno != ESRCH) {
+ if (still_ppp()) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCDELRT): %m (%d)", errno);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * sifproxyarp - Make a proxy ARP entry for the peer.
+ */
+
+int sifproxyarp (int unit, u_int32_t his_adr)
+{
+ struct arpreq arpreq;
+
+ if (has_proxy_arp == 0) {
+ memset (&arpreq, '\0', sizeof(arpreq));
+
+ SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
+ ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = his_adr;
+ arpreq.arp_flags = ATF_PERM | ATF_PUBL;
+/*
+ * Get the hardware address of an interface on the same subnet
+ * as our local address.
+ */
+ if (!get_ether_addr(his_adr, &arpreq.arp_ha, proxy_arp_dev,
+ sizeof(proxy_arp_dev))) {
+ error("Cannot determine ethernet address for proxy ARP");
+ return 0;
+ }
+ strlcpy(arpreq.arp_dev, proxy_arp_dev, sizeof(arpreq.arp_dev));
+
+ if (ioctl(sock_fd, SIOCSARP, (caddr_t)&arpreq) < 0) {
+ if ( ! ok_error ( errno ))
+ error("ioctl(SIOCSARP): %m(%d)", errno);
+ return 0;
+ }
+ proxy_arp_addr = his_adr;
+ has_proxy_arp = 1;
+ }
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * cifproxyarp - Delete the proxy ARP entry for the peer.
+ */
+
+int cifproxyarp (int unit, u_int32_t his_adr)
+{
+ struct arpreq arpreq;
+
+ if (has_proxy_arp) {
+ has_proxy_arp = 0;
+ memset (&arpreq, '\0', sizeof(arpreq));
+ SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
+ ((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = his_adr;
+ arpreq.arp_flags = ATF_PERM | ATF_PUBL;
+ strlcpy(arpreq.arp_dev, proxy_arp_dev, sizeof(arpreq.arp_dev));
+
+ if (ioctl(sock_fd, SIOCDARP, (caddr_t)&arpreq) < 0) {
+ if ( ! ok_error ( errno ))
+ warn("ioctl(SIOCDARP): %m(%d)", errno);
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/********************************************************************
+ *
+ * get_ether_addr - get the hardware address of an interface on the
+ * the same subnet as ipaddr.
+ */
+
+static int get_ether_addr (u_int32_t ipaddr,
+ struct sockaddr *hwaddr,
+ char *name, int namelen)
+{
+ struct ifreq *ifr, *ifend;
+ u_int32_t ina, mask;
+ struct ifreq ifreq;
+ struct ifconf ifc;
+ struct ifreq ifs[MAX_IFS];
+
+ ifc.ifc_len = sizeof(ifs);
+ ifc.ifc_req = ifs;
+ if (ioctl(sock_fd, SIOCGIFCONF, &ifc) < 0) {
+ if ( ! ok_error ( errno ))
+ error("ioctl(SIOCGIFCONF): %m(%d)", errno);
+ return 0;
+ }
+
+ SYSDEBUG ((LOG_DEBUG, "proxy arp: scanning %d interfaces for IP %s",
+ ifc.ifc_len / sizeof(struct ifreq), ip_ntoa(ipaddr)));
+/*
+ * Scan through looking for an interface with an Internet
+ * address on the same subnet as `ipaddr'.
+ */
+ ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
+ for (ifr = ifc.ifc_req; ifr < ifend; ifr++) {
+ if (ifr->ifr_addr.sa_family == AF_INET) {
+ ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+ strlcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
+ SYSDEBUG ((LOG_DEBUG, "proxy arp: examining interface %s",
+ ifreq.ifr_name));
+/*
+ * Check that the interface is up, and not point-to-point
+ * nor loopback.
+ */
+ if (ioctl(sock_fd, SIOCGIFFLAGS, &ifreq) < 0)
+ continue;
+
+ if (((ifreq.ifr_flags ^ FLAGS_GOOD) & FLAGS_MASK) != 0)
+ continue;
+/*
+ * Get its netmask and check that it's on the right subnet.
+ */
+ if (ioctl(sock_fd, SIOCGIFNETMASK, &ifreq) < 0)
+ continue;
+
+ mask = ((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr;
+ SYSDEBUG ((LOG_DEBUG, "proxy arp: interface addr %s mask %lx",
+ ip_ntoa(ina), ntohl(mask)));
+
+ if (((ipaddr ^ ina) & mask) != 0)
+ continue;
+ break;
+ }
+ }
+
+ if (ifr >= ifend)
+ return 0;
+
+ strlcpy(name, ifreq.ifr_name, namelen);
+ info("found interface %s for proxy arp", name);
+/*
+ * Now get the hardware address.
+ */
+ memset (&ifreq.ifr_hwaddr, 0, sizeof (struct sockaddr));
+ if (ioctl (sock_fd, SIOCGIFHWADDR, &ifreq) < 0) {
+ error("SIOCGIFHWADDR(%s): %m(%d)", ifreq.ifr_name, errno);
+ return 0;
+ }
+
+ memcpy (hwaddr,
+ &ifreq.ifr_hwaddr,
+ sizeof (struct sockaddr));
+
+ SYSDEBUG ((LOG_DEBUG,
+ "proxy arp: found hwaddr %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
+ (int) ((unsigned char *) &hwaddr->sa_data)[0],
+ (int) ((unsigned char *) &hwaddr->sa_data)[1],
+ (int) ((unsigned char *) &hwaddr->sa_data)[2],
+ (int) ((unsigned char *) &hwaddr->sa_data)[3],
+ (int) ((unsigned char *) &hwaddr->sa_data)[4],
+ (int) ((unsigned char *) &hwaddr->sa_data)[5],
+ (int) ((unsigned char *) &hwaddr->sa_data)[6],
+ (int) ((unsigned char *) &hwaddr->sa_data)[7]));
+ return 1;
+}
+
+/********************************************************************
+ *
+ * Return user specified netmask, modified by any mask we might determine
+ * for address `addr' (in network byte order).
+ * Here we scan through the system's list of interfaces, looking for
+ * any non-point-to-point interfaces which might appear to be on the same
+ * network as `addr'. If we find any, we OR in their netmask to the
+ * user-specified netmask.
+ */
+
+u_int32_t GetMask (u_int32_t addr)
+{
+ u_int32_t mask, nmask, ina;
+ struct ifreq *ifr, *ifend, ifreq;
+ struct ifconf ifc;
+ struct ifreq ifs[MAX_IFS];
+
+ addr = ntohl(addr);
+
+ if (IN_CLASSA(addr)) /* determine network mask for address class */
+ nmask = IN_CLASSA_NET;
+ else if (IN_CLASSB(addr))
+ nmask = IN_CLASSB_NET;
+ else
+ nmask = IN_CLASSC_NET;
+
+ /* class D nets are disallowed by bad_ip_adrs */
+ mask = netmask | htonl(nmask);
+/*
+ * Scan through the system's network interfaces.
+ */
+ ifc.ifc_len = sizeof(ifs);
+ ifc.ifc_req = ifs;
+ if (ioctl(sock_fd, SIOCGIFCONF, &ifc) < 0) {
+ if ( ! ok_error ( errno ))
+ warn("ioctl(SIOCGIFCONF): %m(%d)", errno);
+ return mask;
+ }
+
+ ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
+ for (ifr = ifc.ifc_req; ifr < ifend; ifr++) {
+/*
+ * Check the interface's internet address.
+ */
+ if (ifr->ifr_addr.sa_family != AF_INET)
+ continue;
+ ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+ if (((ntohl(ina) ^ addr) & nmask) != 0)
+ continue;
+/*
+ * Check that the interface is up, and not point-to-point nor loopback.
+ */
+ strlcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
+ if (ioctl(sock_fd, SIOCGIFFLAGS, &ifreq) < 0)
+ continue;
+
+ if (((ifreq.ifr_flags ^ FLAGS_GOOD) & FLAGS_MASK) != 0)
+ continue;
+/*
+ * Get its netmask and OR it into our mask.
+ */
+ if (ioctl(sock_fd, SIOCGIFNETMASK, &ifreq) < 0)
+ continue;
+ mask |= ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr.s_addr;
+ break;
+ }
+ return mask;
+}
+
+/********************************************************************
+ *
+ * Internal routine to decode the version.modification.patch level
+ */
+
+static void decode_version (char *buf, int *version,
+ int *modification, int *patch)
+{
+ *version = (int) strtoul (buf, &buf, 10);
+ *modification = 0;
+ *patch = 0;
+
+ if (*buf == '.') {
+ ++buf;
+ *modification = (int) strtoul (buf, &buf, 10);
+ if (*buf == '.') {
+ ++buf;
+ *patch = (int) strtoul (buf, &buf, 10);
+ }
+ }
+
+ if (*buf != '\0') {
+ *version =
+ *modification =
+ *patch = 0;
+ }
+}
+
+/********************************************************************
+ *
+ * Procedure to determine if the PPP line discipline is registered.
+ */
+
+static int
+ppp_registered(void)
+{
+ int local_fd;
+ int init_disc = -1;
+ int mfd = -1;
+ int ret = 0;
+
+ if (devnam[0] == 0) {
+ /* running with notty or pty option */
+ char slave[16];
+ if (!get_pty(&mfd, &local_fd, slave, 0))
+ return 0;
+ } else {
+ local_fd = open(devnam, O_NONBLOCK | O_RDWR, 0);
+ if (local_fd < 0) {
+ error("Failed to open %s: %m(%d)", devnam, errno);
+ return 0;
+ }
+ }
+
+/*
+ * Read the initial line discipline and try to put the device into the
+ * PPP dicipline.
+ */
+ if (ioctl(local_fd, TIOCGETD, &init_disc) < 0) {
+ error("ioctl(TIOCGETD): %m(%d)", errno);
+ } else if (ioctl(local_fd, TIOCSETD, &ppp_disc) < 0) {
+ error("ioctl(TIOCSETD(PPP)): %m(%d)", errno);
+ } else if (ioctl(local_fd, TIOCSETD, &init_disc) < 0) {
+ error("ioctl(TIOCSETD(%d)): %m(%d)", init_disc, errno);
+ } else
+ ret = 1;
+
+ close (local_fd);
+ if (mfd >= 0)
+ close(mfd);
+ return ret;
+}
+
+/********************************************************************
+ *
+ * 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(void)
+{
+ int s, ok;
+ struct ifreq ifr;
+ int size;
+ int my_version, my_modification, my_patch;
+ extern char *no_ppp_msg;
+/*
+ * Open a socket for doing the ioctl operations.
+ */
+ s = socket(AF_INET, SOCK_DGRAM, 0);
+ if (s < 0)
+ return 0;
+
+ strlcpy (ifr.ifr_name, "ppp0", sizeof (ifr.ifr_name));
+ ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0;
+/*
+ * If the device did not exist then attempt to create one by putting the
+ * current tty into the PPP discipline. If this works then obtain the
+ * flags for the device again.
+ */
+ if (!ok) {
+ if (ppp_registered()) {
+ strlcpy (ifr.ifr_name, "ppp0", sizeof (ifr.ifr_name));
+ ok = ioctl(s, SIOCGIFFLAGS, (caddr_t) &ifr) >= 0;
+ }
+ }
+/*
+ * Ensure that the hardware address is for PPP and not something else
+ */
+ if (ok)
+ ok = ioctl (s, SIOCGIFHWADDR, (caddr_t) &ifr) >= 0;
+
+ if (ok && ((ifr.ifr_hwaddr.sa_family & ~0xFF) != ARPHRD_PPP))
+ ok = 0;
+
+ if (!ok)
+ no_ppp_msg =
+ "This system lacks kernel support for PPP. This could be because\n"
+ "the PPP kernel module is not loaded, or because the kernel is\n"
+ "not configured for PPP. See the README.linux file in the\n"
+ "ppp-2.3.7 distribution.\n";
+
+/*
+ * This is the PPP device. Validate the version of the driver at this
+ * point to ensure that this program will work with the driver.
+ */
+ else {
+ char abBuffer [1024];
+
+ ifr.ifr_data = abBuffer;
+ size = ioctl (s, SIOCGPPPVER, (caddr_t) &ifr);
+ if (size < 0) {
+ error("Couldn't read driver version: %m");
+ ok = 0;
+ no_ppp_msg = "Sorry, couldn't verify kernel driver version\n";
+
+ } else {
+ decode_version(abBuffer,
+ &driver_version,
+ &driver_modification,
+ &driver_patch);
+/*
+ * Validate the version of the driver against the version that we used.
+ */
+ decode_version(VERSION,
+ &my_version,
+ &my_modification,
+ &my_patch);
+
+ /* The version numbers must match */
+ if (driver_version != my_version)
+ ok = 0;
+
+ /* The modification levels must be legal */
+ if (driver_modification < 3) {
+ if (driver_modification >= 2) {
+ /* we can cope with 2.2.0 and above */
+ driver_is_old = 1;
+ } else {
+ ok = 0;
+ }
+ }
+
+ close (s);
+ if (!ok) {
+ slprintf(route_buffer, sizeof(route_buffer),
+ "Sorry - PPP driver version %d.%d.%d is out of date\n",
+ driver_version, driver_modification, driver_patch);
+
+ no_ppp_msg = route_buffer;
+ }
+ }
+ }
+ return ok;
+}
+
+/********************************************************************
+ *
+ * Update the wtmp file with the appropriate user name and tty device.
+ */
+
+void logwtmp (const char *line, const char *name, const char *host)
+{
+ int wtmp;
+ struct utmp ut, *utp;
+ pid_t mypid = getpid();
+/*
+ * Update the signon database for users.
+ * Christoph Lameter: Copied from poeigl-1.36 Jan 3, 1996
+ */
+ utmpname(_PATH_UTMP);
+ setutent();
+ while ((utp = getutent()) && (utp->ut_pid != mypid))
+ /* nothing */;
+
+ /* Is this call really necessary? There is another one after the 'put' */
+ endutent();
+
+ if (utp)
+ memcpy(&ut, utp, sizeof(ut));
+ else
+ /* some gettys/telnetds don't initialize utmp... */
+ memset(&ut, 0, sizeof(ut));
+
+ if (ut.ut_id[0] == 0)
+ strlcpy(ut.ut_id, line + 3, sizeof(ut.ut_id));
+
+ strlcpy(ut.ut_user, name, sizeof(ut.ut_user));
+ strlcpy(ut.ut_line, line, sizeof(ut.ut_line));
+
+ time(&ut.ut_time);
+
+ ut.ut_type = USER_PROCESS;
+ ut.ut_pid = mypid;
+
+ /* Insert the host name if one is supplied */
+ if (*host)
+ strlcpy (ut.ut_host, host, sizeof(ut.ut_host));
+
+ /* Insert the IP address of the remote system if IP is enabled */
+ if (ipcp_protent.enabled_flag && ipcp_hisoptions[0].neg_addr)
+ memcpy(&ut.ut_addr, (char *) &ipcp_hisoptions[0].hisaddr,
+ sizeof(ut.ut_addr));
+
+ /* CL: Makes sure that the logout works */
+ if (*host == 0 && *name==0)
+ ut.ut_host[0]=0;
+
+ pututline(&ut);
+ endutent();
+/*
+ * Update the wtmp file.
+ */
+ wtmp = open(_PATH_WTMP, O_APPEND|O_WRONLY);
+ if (wtmp >= 0) {
+ flock(wtmp, LOCK_EX);
+
+ /* we really should check for error on the write for a full disk! */
+ write (wtmp, (char *)&ut, sizeof(ut));
+ close (wtmp);
+
+ flock(wtmp, LOCK_UN);
+ }
+}
+
+/********************************************************************
+ * Code for locking/unlocking the serial device.
+ * This code is derived from chat.c.
+ */
+
+/*
+ * lock - create a lock file for the named device
+ */
+
+int lock (char *dev)
+{
+#ifdef LOCKLIB
+ int result;
+ lock_file = strdup(dev);
+ if (lock_file == NULL)
+ novm("lock file name");
+ result = mklock (dev, (void *) 0);
+
+ if (result > 0) {
+ notice("Device %s is locked by pid %d", dev, result);
+ free (lock_file);
+ lock_file = NULL;
+ result = -1;
+ }
+ else {
+ if (result < 0) {
+ error("Can't create lock file %s", lock_file);
+ free (lock_file);
+ lock_file = NULL;
+ result = -1;
+ }
+ }
+ return (result);
+#else
+ char hdb_lock_buffer[12];
+ int fd, n;
+ int pid = getpid();
+ char *p;
+ size_t l;
+
+ p = strrchr(dev, '/');
+ if (p != NULL)
+ dev = ++p;
+
+ l = strlen(LOCK_PREFIX) + strlen(dev) + 1;
+ lock_file = malloc(l);
+ if (lock_file == NULL)
+ novm("lock file name");
+
+ slprintf(lock_file, l, "%s%s", LOCK_PREFIX, dev);
+/*
+ * Attempt to create the lock file at this point.
+ */
+ while (1) {
+ fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644);
+ if (fd >= 0) {
+ pid = getpid();
+#ifndef PID_BINARY
+ slprintf(hdb_lock_buffer, sizeof(hdb_lock_buffer), "%010d\n", pid);
+ write (fd, hdb_lock_buffer, 11);
+#else
+ write(fd, &pid, sizeof (pid));
+#endif
+ close(fd);
+ return 0;
+ }
+/*
+ * If the file exists then check to see if the pid is stale
+ */
+ if (errno == EEXIST) {
+ fd = open(lock_file, O_RDONLY, 0);
+ if (fd < 0) {
+ if (errno == ENOENT) /* This is just a timing problem. */
+ continue;
+ break;
+ }
+
+ /* Read the lock file to find out who has the device locked */
+ n = read (fd, hdb_lock_buffer, 11);
+ close (fd);
+ if (n < 0) {
+ error("Can't read pid from lock file %s", lock_file);
+ break;
+ }
+
+ /* See the process still exists. */
+ if (n > 0) {
+#ifndef PID_BINARY
+ hdb_lock_buffer[n] = '\0';
+ sscanf (hdb_lock_buffer, " %d", &pid);
+#else
+ pid = ((int *) hdb_lock_buffer)[0];
+#endif
+ if (pid == 0 || pid == getpid()
+ || (kill(pid, 0) == -1 && errno == ESRCH))
+ n = 0;
+ }
+
+ /* If the process does not exist then try to remove the lock */
+ if (n == 0 && unlink (lock_file) == 0) {
+ notice("Removed stale lock on %s (pid %d)",
+ dev, pid);
+ continue;
+ }
+
+ notice("Device %s is locked by pid %d", dev, pid);
+ break;
+ }
+
+ error("Can't create lock file %s: %m(%d)", lock_file, errno);
+ break;
+ }
+
+ free(lock_file);
+ lock_file = NULL;
+ return -1;
+#endif
+}
+
+
+/********************************************************************
+ *
+ * unlock - remove our lockfile
+ */
+
+void unlock(void)
+{
+ if (lock_file) {
+#ifdef LOCKLIB
+ (void) rmlock (lock_file, (void *) 0);
+#else
+ unlink(lock_file);
+#endif
+ free(lock_file);
+ lock_file = NULL;
+ }
+}
+
+/********************************************************************
+ *
+ * sifvjcomp - config tcp header compression
+ */
+
+int sifvjcomp (int u, int vjcomp, int cidcomp, int maxcid)
+{
+ u_int x = get_flags();
+
+ if (vjcomp) {
+ if (ioctl (ppp_fd, PPPIOCSMAXCID, (caddr_t) &maxcid) < 0) {
+ if (! ok_error (errno))
+ error("ioctl(PPPIOCSMAXCID): %m(%d)", errno);
+ vjcomp = 0;
+ }
+ }
+
+ x = vjcomp ? x | SC_COMP_TCP : x &~ SC_COMP_TCP;
+ x = cidcomp ? x & ~SC_NO_TCP_CCID : x | SC_NO_TCP_CCID;
+ set_flags (x);
+
+ return 1;
+}
+
+/********************************************************************
+ *