+ int x;
+
+ x = (isopen? SC_CCP_OPEN: 0) | (isup? SC_CCP_UP: 0);
+ if (still_ppp() && ppp_dev_fd >= 0)
+ modify_flags(ppp_dev_fd, SC_CCP_OPEN|SC_CCP_UP, x);
+}
+
+#ifdef PPP_FILTER
+/*
+ * set_filters - set the active and pass filters in the kernel driver.
+ */
+int set_filters(struct bpf_program *pass, struct bpf_program *active)
+{
+ struct sock_fprog fp;
+
+ fp.len = pass->bf_len;
+ fp.filter = (struct sock_filter *) pass->bf_insns;
+ if (ioctl(ppp_dev_fd, PPPIOCSPASS, &fp) < 0) {
+ if (errno == ENOTTY)
+ warn("kernel does not support PPP filtering");
+ else
+ error("Couldn't set pass-filter in kernel: %m");
+ return 0;
+ }
+ fp.len = active->bf_len;
+ fp.filter = (struct sock_filter *) active->bf_insns;
+ if (ioctl(ppp_dev_fd, PPPIOCSACTIVE, &fp) < 0) {
+ error("Couldn't set active-filter in kernel: %m");
+ return 0;
+ }
+ return 1;
+}
+#endif /* PPP_FILTER */
+
+/********************************************************************
+ *
+ * get_idle_time - return how long the link has been idle.
+ */
+int
+get_idle_time(int u, struct ppp_idle *ip)
+{
+ return ioctl(ppp_dev_fd, PPPIOCGIDLE, ip) >= 0;
+}
+
+/********************************************************************
+ *
+ * get_ppp_stats - return statistics for the link.
+ */
+int
+get_ppp_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;
+ stats->pkts_in = req.stats.p.ppp_ipackets;
+ stats->pkts_out = req.stats.p.ppp_opackets;
+ 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 flags;
+
+ if (ioctl(ppp_dev_fd, PPPIOCGFLAGS, &flags) < 0) {
+ error("Couldn't read compression error flags: %m");
+ flags = 0;
+ }
+ return flags & SC_DC_FERROR;
+}
+
+/********************************************************************
+ *
+ * path_to_procfs - find the path to the proc file system mount point
+ */
+static char proc_path[MAXPATHLEN];
+static int proc_path_len;
+
+static char *path_to_procfs(const char *tail)
+{
+ struct mntent *mntent;
+ FILE *fp;
+
+ if (proc_path_len == 0) {
+ /* Default the mount location of /proc */
+ strlcpy (proc_path, "/proc", sizeof(proc_path));
+ proc_path_len = 5;
+ fp = fopen(MOUNTED, "r");
+ if (fp != NULL) {
+ while ((mntent = getmntent(fp)) != NULL) {
+ if (strcmp(mntent->mnt_type, MNTTYPE_IGNORE) == 0)
+ continue;
+ if (strcmp(mntent->mnt_type, "proc") == 0) {
+ strlcpy(proc_path, mntent->mnt_dir, sizeof(proc_path));
+ proc_path_len = strlen(proc_path);
+ break;
+ }
+ }
+ fclose (fp);
+ }
+ }
+
+ strlcpy(proc_path + proc_path_len, tail,
+ sizeof(proc_path) - proc_path_len);
+ return proc_path;
+}
+
+/*
+ * /proc/net/route parsing stuff.
+ */
+#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_metric_col, route_mask_col;
+static int route_num_cols;
+
+static int open_route_table (void);
+static void close_route_table (void);
+static int read_route_table (struct rtentry *rt);
+
+/********************************************************************
+ *
+ * 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_procfs("/net/route");
+ route_fd = fopen (path, "r");
+ if (route_fd == NULL) {
+ error("can't open routing table %s: %m", path);
+ return 0;
+ }
+
+ route_dev_col = 0; /* default to usual columns */
+ route_dest_col = 1;
+ route_gw_col = 2;
+ route_flags_col = 3;
+ route_metric_col = 6;
+ 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 */
+ p = NULL;
+ }
+
+ SET_SA_FAMILY (rt->rt_dst, AF_INET);
+ SET_SA_FAMILY (rt->rt_gateway, AF_INET);
+
+ SIN_ADDR(rt->rt_dst) = strtoul(cols[route_dest_col], NULL, 16);
+ SIN_ADDR(rt->rt_gateway) = strtoul(cols[route_gw_col], NULL, 16);
+ SIN_ADDR(rt->rt_genmask) = strtoul(cols[route_mask_col], NULL, 16);
+
+ rt->rt_flags = (short) strtoul(cols[route_flags_col], NULL, 16);
+ rt->rt_metric = (short) strtoul(cols[route_metric_col], NULL, 10);
+ rt->rt_dev = cols[route_dev_col];
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * defaultroute_exists - determine if there is a default route
+ * with the given metric (or negative for any)
+ */
+
+static int defaultroute_exists (struct rtentry *rt, int metric)
+{
+ int result = 0;
+
+ if (!open_route_table())
+ return 0;
+
+ while (read_route_table(rt) != 0) {
+ if ((rt->rt_flags & RTF_UP) == 0)
+ continue;
+
+ if (kernel_version > KVERSION(2,1,0) && SIN_ADDR(rt->rt_genmask) != 0)
+ continue;
+ if (SIN_ADDR(rt->rt_dst) == 0L && (metric < 0
+ || rt->rt_metric == metric)) {
+ 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 & SIN_ADDR(rt.rt_genmask)) == SIN_ADDR(rt.rt_dst)) {
+ result = 1;
+ break;
+ }
+ }
+
+ close_route_table();
+ return result;
+}
+
+/********************************************************************
+ *
+ * sifdefaultroute - assign a default route through the address given.
+ *
+ * If the global default_rt_repl_rest flag is set, then this function
+ * already replaced the original system defaultroute with some other
+ * route and it should just replace the current defaultroute with
+ * another one, without saving the current route. Use: demand mode,
+ * when pppd sets first a defaultroute it it's temporary ppp0 addresses
+ * and then changes the temporary addresses to the addresses for the real
+ * ppp connection when it has come up.
+ */
+
+int sifdefaultroute (int unit, u_int32_t ouraddr, u_int32_t gateway, bool replace)
+{
+ struct rtentry rt, tmp_rt;
+ struct rtentry *del_rt = NULL;
+
+ if (default_rt_repl_rest) {
+ /* We have already replaced the original defaultroute, if we
+ * are called again, we will delete the current default route
+ * and set the new default route in this function.
+ * - this is normally only the case the doing demand: */
+ if (defaultroute_exists(&tmp_rt, -1))
+ del_rt = &tmp_rt;
+ } else if (defaultroute_exists(&old_def_rt, -1 ) &&
+ strcmp( old_def_rt.rt_dev, ifname) != 0) {
+ /*
+ * We did not yet replace an existing default route, let's
+ * check if we should save and replace a default route:
+ */
+ u_int32_t old_gateway = SIN_ADDR(old_def_rt.rt_gateway);
+
+ if (old_gateway != gateway) {
+ if (!replace) {
+ error("not replacing default route to %s [%I]",
+ old_def_rt.rt_dev, old_gateway);
+ return 0;
+ } else {
+ /* we need to copy rt_dev because we need it permanent too: */
+ char * tmp_dev = malloc(strlen(old_def_rt.rt_dev)+1);
+ strcpy(tmp_dev, old_def_rt.rt_dev);
+ old_def_rt.rt_dev = tmp_dev;
+
+ notice("replacing old default route to %s [%I]",
+ old_def_rt.rt_dev, old_gateway);
+ default_rt_repl_rest = 1;
+ del_rt = &old_def_rt;
+ }
+ }
+ }
+
+ memset (&rt, 0, sizeof (rt));
+ SET_SA_FAMILY (rt.rt_dst, AF_INET);
+
+ rt.rt_dev = ifname;
+ rt.rt_metric = dfl_route_metric + 1; /* +1 for binary compatibility */
+
+ if (kernel_version > KVERSION(2,1,0)) {
+ SET_SA_FAMILY (rt.rt_genmask, AF_INET);
+ SIN_ADDR(rt.rt_genmask) = 0L;
+ }
+
+ rt.rt_flags = RTF_UP;
+ if (ioctl(sock_fd, SIOCADDRT, &rt) < 0) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCADDRT): %m");
+ return 0;
+ }
+ if (default_rt_repl_rest && del_rt)
+ if (ioctl(sock_fd, SIOCDELRT, del_rt) < 0) {
+ if ( ! ok_error ( errno ))
+ error("del old default route ioctl(SIOCDELRT): %m(%d)", errno);
+ return 0;
+ }
+
+ have_default_route = 1;
+ 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;
+
+ have_default_route = 0;
+
+ memset (&rt, '\0', sizeof (rt));
+ SET_SA_FAMILY (rt.rt_dst, AF_INET);
+ SET_SA_FAMILY (rt.rt_gateway, AF_INET);
+
+ rt.rt_dev = ifname;
+
+ rt.rt_dev = ifname;
+ rt.rt_metric = dfl_route_metric + 1; /* +1 for binary compatibility */
+
+ if (kernel_version > KVERSION(2,1,0)) {
+ SET_SA_FAMILY (rt.rt_genmask, AF_INET);
+ SIN_ADDR(rt.rt_genmask) = 0L;
+ }
+
+ rt.rt_flags = RTF_UP;
+ if (ioctl(sock_fd, SIOCDELRT, &rt) < 0 && errno != ESRCH) {
+ if (still_ppp()) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCDELRT): %m");
+ return 0;
+ }
+ }
+ if (default_rt_repl_rest) {
+ notice("restoring old default route to %s [%I]",
+ old_def_rt.rt_dev, SIN_ADDR(old_def_rt.rt_gateway));
+ if (ioctl(sock_fd, SIOCADDRT, &old_def_rt) < 0) {
+ if ( ! ok_error ( errno ))
+ error("restore default route ioctl(SIOCADDRT): %m(%d)", errno);
+ return 0;
+ }
+ default_rt_repl_rest = 0;
+ }
+
+ return 1;
+}
+
+#ifdef INET6
+/*
+ * /proc/net/ipv6_route parsing stuff.
+ */
+static int route_dest_plen_col;
+static int open_route6_table (void);
+static int read_route6_table (struct in6_rtmsg *rt);
+
+/********************************************************************
+ *
+ * open_route6_table - open the interface to the route table
+ */
+static int open_route6_table (void)
+{
+ char *path;
+
+ close_route_table();
+
+ path = path_to_procfs("/net/ipv6_route");
+ route_fd = fopen (path, "r");
+ if (route_fd == NULL) {
+ error("can't open routing table %s: %m", path);
+ return 0;
+ }
+
+ /* default to usual columns */
+ route_dest_col = 0;
+ route_dest_plen_col = 1;
+ route_gw_col = 4;
+ route_metric_col = 5;
+ route_flags_col = 8;
+ route_dev_col = 9;
+ route_num_cols = 10;
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * read_route6_table - read the next entry from the route table
+ */
+
+static void hex_to_in6_addr(struct in6_addr *addr, const char *s)
+{
+ char hex8[9];
+ unsigned i;
+ uint32_t v;
+
+ hex8[8] = 0;
+ for (i = 0; i < 4; i++) {
+ memcpy(hex8, s + 8*i, 8);
+ v = strtoul(hex8, NULL, 16);
+ addr->s6_addr32[i] = v;
+ }
+}
+
+static int read_route6_table(struct in6_rtmsg *rt)
+{
+ char *cols[ROUTE_MAX_COLS], *p;
+ int col;
+
+ memset (rt, '\0', sizeof (struct in6_rtmsg));
+
+ 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 */
+ p = NULL;
+ }
+
+ hex_to_in6_addr(&rt->rtmsg_dst, cols[route_dest_col]);
+ rt->rtmsg_dst_len = strtoul(cols[route_dest_plen_col], NULL, 16);
+ hex_to_in6_addr(&rt->rtmsg_gateway, cols[route_gw_col]);
+
+ rt->rtmsg_metric = strtoul(cols[route_metric_col], NULL, 16);
+ rt->rtmsg_flags = strtoul(cols[route_flags_col], NULL, 16);
+ rt->rtmsg_ifindex = if_nametoindex(cols[route_dev_col]);
+
+ return 1;
+}
+
+/********************************************************************
+ *
+ * defaultroute6_exists - determine if there is a default route
+ */
+
+static int defaultroute6_exists (struct in6_rtmsg *rt, int metric)
+{
+ int result = 0;
+
+ if (!open_route6_table())
+ return 0;
+
+ while (read_route6_table(rt) != 0) {
+ if ((rt->rtmsg_flags & RTF_UP) == 0)
+ continue;
+
+ if (rt->rtmsg_dst_len != 0)
+ continue;
+ if (rt->rtmsg_dst.s6_addr32[0] == 0L
+ && rt->rtmsg_dst.s6_addr32[1] == 0L
+ && rt->rtmsg_dst.s6_addr32[2] == 0L
+ && rt->rtmsg_dst.s6_addr32[3] == 0L
+ && (metric < 0 || rt->rtmsg_metric == metric)) {
+ result = 1;
+ break;
+ }
+ }
+
+ close_route_table();
+ return result;
+}
+
+/********************************************************************
+ *
+ * sif6defaultroute - assign a default route through the address given.
+ *
+ * If the global default_rt_repl_rest flag is set, then this function
+ * already replaced the original system defaultroute with some other
+ * route and it should just replace the current defaultroute with
+ * another one, without saving the current route. Use: demand mode,
+ * when pppd sets first a defaultroute it it's temporary ppp0 addresses
+ * and then changes the temporary addresses to the addresses for the real
+ * ppp connection when it has come up.
+ */
+
+int sif6defaultroute (int unit, eui64_t ouraddr, eui64_t gateway)
+{
+ struct in6_rtmsg rt;
+ char buf[IF_NAMESIZE];
+
+ if (defaultroute6_exists(&rt, dfl_route_metric) &&
+ rt.rtmsg_ifindex != if_nametoindex(ifname)) {
+ if (rt.rtmsg_flags & RTF_GATEWAY)
+ error("not replacing existing default route via gateway");
+ else
+ error("not replacing existing default route through %s",
+ if_indextoname(rt.rtmsg_ifindex, buf));
+ return 0;
+ }
+
+ memset (&rt, 0, sizeof (rt));
+
+ rt.rtmsg_ifindex = if_nametoindex(ifname);
+ rt.rtmsg_metric = dfl_route_metric + 1; /* +1 for binary compatibility */
+ rt.rtmsg_dst_len = 0;
+
+ rt.rtmsg_flags = RTF_UP;
+ if (ioctl(sock6_fd, SIOCADDRT, &rt) < 0) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCADDRT): %m");
+ return 0;
+ }
+
+ have_default_route6 = 1;
+ return 1;
+}
+
+/********************************************************************
+ *
+ * cif6defaultroute - delete a default route through the address given.
+ */
+
+int cif6defaultroute (int unit, eui64_t ouraddr, eui64_t gateway)
+{
+ struct in6_rtmsg rt;
+
+ have_default_route6 = 0;
+
+ memset (&rt, '\0', sizeof (rt));
+
+ rt.rtmsg_ifindex = if_nametoindex(ifname);
+ rt.rtmsg_metric = dfl_route_metric + 1; /* +1 for binary compatibility */
+ rt.rtmsg_dst_len = 0;
+
+ rt.rtmsg_flags = RTF_UP;
+ if (ioctl(sock6_fd, SIOCDELRT, &rt) < 0 && errno != ESRCH) {
+ if (still_ppp()) {
+ if ( ! ok_error ( errno ))
+ error("default route ioctl(SIOCDELRT): %m");
+ return 0;
+ }
+ }
+
+ return 1;
+}
+#endif /* INET6 */
+
+/********************************************************************
+ *
+ * sifproxyarp - Make a proxy ARP entry for the peer.
+ */
+
+int sifproxyarp (int unit, u_int32_t his_adr)
+{
+ struct arpreq arpreq;
+ char *forw_path;
+
+ if (has_proxy_arp == 0) {
+ memset (&arpreq, '\0', sizeof(arpreq));
+
+ SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
+ SIN_ADDR(arpreq.arp_pa) = 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");
+ return 0;
+ }
+ proxy_arp_addr = his_adr;
+ has_proxy_arp = 1;
+
+ if (tune_kernel) {
+ forw_path = path_to_procfs("/sys/net/ipv4/ip_forward");
+ if (forw_path != 0) {
+ int fd = open(forw_path, O_WRONLY);
+ if (fd >= 0) {
+ if (write(fd, "1", 1) != 1)
+ error("Couldn't enable IP forwarding: %m");
+ close(fd);
+ }
+ }
+ }
+ }
+
+ 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);
+ SIN_ADDR(arpreq.arp_pa) = 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");
+ 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;
+ char *aliasp;
+ struct ifreq ifreq, bestifreq;
+ struct ifconf ifc;
+ struct ifreq ifs[MAX_IFS];
+
+ u_int32_t bestmask=0;
+ int found_interface = 0;
+
+ ifc.ifc_len = sizeof(ifs);
+ ifc.ifc_req = ifs;
+ if (ioctl(sock_fd, SIOCGIFCONF, &ifc) < 0) {
+ if ( ! ok_error ( errno ))
+ error("ioctl(SIOCGIFCONF): %m (line %d)", __LINE__);
+ return 0;
+ }
+
+/*
+ * 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 = SIN_ADDR(ifr->ifr_addr);
+ strlcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(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 = SIN_ADDR(ifreq.ifr_addr);
+
+ if (((ipaddr ^ ina) & mask) != 0)
+ continue; /* no match */
+ /* matched */
+ if (mask >= bestmask) {
+ /* Compare using >= instead of > -- it is possible for
+ an interface to have a netmask of 0.0.0.0 */
+ found_interface = 1;
+ bestifreq = ifreq;
+ bestmask = mask;
+ }
+ }
+ }
+
+ if (!found_interface) return 0;
+
+ strlcpy(name, bestifreq.ifr_name, namelen);
+
+ /* trim off the :1 in eth0:1 */
+ aliasp = strchr(name, ':');
+ if (aliasp != 0)
+ *aliasp = 0;
+
+ info("found interface %s for proxy arp", name);
+/*
+ * Now get the hardware address.
+ */
+ memset (&bestifreq.ifr_hwaddr, 0, sizeof (struct sockaddr));
+ if (ioctl (sock_fd, SIOCGIFHWADDR, &bestifreq) < 0) {
+ error("SIOCGIFHWADDR(%s): %m", bestifreq.ifr_name);
+ return 0;
+ }
+
+ memcpy (hwaddr,
+ &bestifreq.ifr_hwaddr,
+ sizeof (struct sockaddr));
+
+ return 1;
+}
+
+/*
+ * get_if_hwaddr - get the hardware address for the specified
+ * network interface device.
+ */
+int
+get_if_hwaddr(u_char *addr, char *name)
+{
+ struct ifreq ifreq;
+ int ret, sock_fd;
+
+ sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sock_fd < 0)
+ return -1;
+ memset(&ifreq.ifr_hwaddr, 0, sizeof(struct sockaddr));
+ strlcpy(ifreq.ifr_name, name, sizeof(ifreq.ifr_name));
+ ret = ioctl(sock_fd, SIOCGIFHWADDR, &ifreq);
+ close(sock_fd);
+ if (ret >= 0)
+ memcpy(addr, ifreq.ifr_hwaddr.sa_data, 6);
+ return ret;
+}
+
+/*
+ * get_first_ether_hwaddr - get the hardware address for the first
+ * ethernet-style interface on this system.
+ */
+int
+get_first_ether_hwaddr(u_char *addr)
+{
+ struct if_nameindex *if_ni, *i;
+ struct ifreq ifreq;
+ int ret, sock_fd;
+
+ sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sock_fd < 0)
+ return -1;
+
+ if_ni = if_nameindex();
+ if (!if_ni) {
+ close(sock_fd);
+ return -1;
+ }
+
+ ret = -1;
+
+ for (i = if_ni; !(i->if_index == 0 && i->if_name == NULL); i++) {
+ memset(&ifreq.ifr_hwaddr, 0, sizeof(struct sockaddr));
+ strlcpy(ifreq.ifr_name, i->if_name, sizeof(ifreq.ifr_name));
+ ret = ioctl(sock_fd, SIOCGIFHWADDR, &ifreq);
+ if (ret >= 0 && ifreq.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
+ memcpy(addr, ifreq.ifr_hwaddr.sa_data, 6);
+ break;
+ }
+ ret = -1;
+ }
+
+ if_freenameindex(if_ni);
+ close(sock_fd);
+
+ return ret;
+}
+
+/********************************************************************
+ *
+ * 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 (line %d)", __LINE__);
+ 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 = SIN_ADDR(ifr->ifr_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 |= SIN_ADDR(ifreq.ifr_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)
+{
+ char *endp;
+
+ *version = (int) strtoul (buf, &endp, 10);
+ *modification = 0;
+ *patch = 0;
+
+ if (endp != buf && *endp == '.') {
+ buf = endp + 1;
+ *modification = (int) strtoul (buf, &endp, 10);
+ if (endp != buf && *endp == '.') {
+ buf = endp + 1;
+ *patch = (int) strtoul (buf, &buf, 10);
+ }
+ }
+}
+
+/********************************************************************
+ *
+ * Procedure to determine if the PPP line discipline is registered.
+ */
+
+static int
+ppp_registered(void)
+{
+ int local_fd;
+ int mfd = -1;
+ int ret = 0;
+ char slave[16];
+
+ /*
+ * We used to open the serial device and set it to the ppp line
+ * discipline here, in order to create a ppp unit. But that is
+ * not a good idea - the user might have specified a device that
+ * they can't open (permission, or maybe it doesn't really exist).
+ * So we grab a pty master/slave pair and use that.
+ */
+ if (!get_pty(&mfd, &local_fd, slave, 0)) {
+ no_ppp_msg = "Couldn't determine if PPP is supported (no free ptys)";
+ return 0;
+ }
+
+ /*
+ * Try to put the device into the PPP discipline.
+ */
+ if (ioctl(local_fd, TIOCSETD, &ppp_disc) < 0) {
+ error("ioctl(TIOCSETD(PPP)): %m (line %d)", __LINE__);
+ } else
+ ret = 1;
+
+ close(local_fd);
+ 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, fd;
+ struct ifreq ifr;
+ int size;
+ int my_version, my_modification, my_patch;
+ int osmaj, osmin, ospatch;
+
+ /* get the kernel version now, since we are called before sys_init */
+ uname(&utsname);
+ osmaj = osmin = ospatch = 0;
+ sscanf(utsname.release, "%d.%d.%d", &osmaj, &osmin, &ospatch);
+ kernel_version = KVERSION(osmaj, osmin, ospatch);
+
+ fd = open("/dev/ppp", O_RDWR);
+ if (fd >= 0) {
+ new_style_driver = 1;
+
+ /* XXX should get from driver */
+ driver_version = 2;
+ driver_modification = 4;
+ driver_patch = 0;
+ close(fd);
+ return 1;
+ }
+
+ if (kernel_version >= KVERSION(2,3,13)) {
+ error("Couldn't open the /dev/ppp device: %m");
+ if (errno == ENOENT)
+ no_ppp_msg =
+ "You need to create the /dev/ppp device node by\n"
+ "executing the following command as root:\n"
+ " mknod /dev/ppp c 108 0\n";
+ else if (errno == ENODEV || errno == ENXIO)
+ no_ppp_msg =
+ "Please load the ppp_generic kernel module.\n";
+ return 0;
+ }
+
+ /* we are running on a really really old kernel */
+ no_ppp_msg =
+ "This system lacks kernel support for PPP. This could be because\n"
+ "the PPP kernel module could not be loaded, or because PPP was not\n"
+ "included in the kernel configuration. If PPP was included as a\n"
+ "module, try `/sbin/modprobe -v ppp'. If that fails, check that\n"
+ "ppp.o exists in /lib/modules/`uname -r`/net.\n"
+ "See README.linux file in the ppp distribution for more details.\n";
+
+/*
+ * 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;
+
+/*
+ * This is the PPP device. Validate the version of the driver at this
+ * point to ensure that this program will work with the driver.
+ */
+ if (ok) {
+ 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;
+ }
+ }
+
+ 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;
+ }
+ }
+ }