+ IPCPDEBUG(("ipcp: down"));
+ /* XXX a bit IPv4-centric here, we only need to get the stats
+ * before the interface is marked down. */
+ update_link_stats(f->unit);
+ if (ip_down_hook)
+ ip_down_hook();
+ if (ipcp_is_up) {
+ ipcp_is_up = 0;
+ np_down(f->unit, PPP_IP);
+ }
+ sifvjcomp(f->unit, 0, 0, 0);
+
+ /*
+ * If we are doing dial-on-demand, set the interface
+ * to queue up outgoing packets (for now).
+ */
+ if (demand) {
+ sifnpmode(f->unit, PPP_IP, NPMODE_QUEUE);
+ } else {
+ sifnpmode(f->unit, PPP_IP, NPMODE_DROP);
+ sifdown(f->unit);
+ ipcp_clear_addrs(f->unit, ipcp_gotoptions[f->unit].ouraddr,
+ ipcp_hisoptions[f->unit].hisaddr);
+ }
+
+ /* Execute the ip-down script */
+ if (ipcp_script_state == s_up && ipcp_script_pid == 0) {
+ ipcp_script_state = s_down;
+ ipcp_script(_PATH_IPDOWN);
+ }
+}
+
+
+/*
+ * ipcp_clear_addrs() - clear the interface addresses, routes,
+ * proxy arp entries, etc.
+ */
+static void
+ipcp_clear_addrs(unit, ouraddr, hisaddr)
+ int unit;
+ u_int32_t ouraddr; /* local address */
+ u_int32_t hisaddr; /* remote address */
+{
+ if (proxy_arp_set[unit]) {
+ cifproxyarp(unit, hisaddr);
+ proxy_arp_set[unit] = 0;
+ }
+ if (default_route_set[unit]) {
+ cifdefaultroute(unit, ouraddr, hisaddr);
+ default_route_set[unit] = 0;
+ }
+ cifaddr(unit, ouraddr, hisaddr);
+}
+
+
+/*
+ * ipcp_finished - possibly shut down the lower layers.
+ */
+static void
+ipcp_finished(f)
+ fsm *f;
+{
+ np_finished(f->unit, PPP_IP);
+}
+
+
+/*
+ * ipcp_script_done - called when the ip-up or ip-down script
+ * has finished.
+ */
+static void
+ipcp_script_done(arg)
+ void *arg;
+{
+ ipcp_script_pid = 0;
+ switch (ipcp_script_state) {
+ case s_up:
+ if (ipcp_fsm[0].state != OPENED) {
+ ipcp_script_state = s_down;
+ ipcp_script(_PATH_IPDOWN);
+ }
+ break;
+ case s_down:
+ if (ipcp_fsm[0].state == OPENED) {
+ ipcp_script_state = s_up;
+ ipcp_script(_PATH_IPUP);
+ }
+ break;
+ }
+}
+
+
+/*
+ * ipcp_script - Execute a script with arguments
+ * interface-name tty-name speed local-IP remote-IP.
+ */
+static void
+ipcp_script(script)
+ char *script;
+{
+ char strspeed[32], strlocal[32], strremote[32];
+ char *argv[8];
+
+ slprintf(strspeed, sizeof(strspeed), "%d", baud_rate);
+ slprintf(strlocal, sizeof(strlocal), "%I", ipcp_gotoptions[0].ouraddr);
+ slprintf(strremote, sizeof(strremote), "%I", ipcp_hisoptions[0].hisaddr);
+
+ argv[0] = script;
+ argv[1] = ifname;
+ argv[2] = devnam;
+ argv[3] = strspeed;
+ argv[4] = strlocal;
+ argv[5] = strremote;
+ argv[6] = ipparam;
+ argv[7] = NULL;
+ ipcp_script_pid = run_program(script, argv, 0, ipcp_script_done, NULL);
+}
+
+/*
+ * create_resolv - create the replacement resolv.conf file
+ */
+static void
+create_resolv(peerdns1, peerdns2)
+ u_int32_t peerdns1, peerdns2;
+{
+ FILE *f;
+
+ f = fopen(_PATH_RESOLV, "w");
+ if (f == NULL) {
+ error("Failed to create %s: %m", _PATH_RESOLV);
+ return;
+ }
+
+ if (peerdns1)
+ fprintf(f, "nameserver %s\n", ip_ntoa(peerdns1));
+
+ if (peerdns2)
+ fprintf(f, "nameserver %s\n", ip_ntoa(peerdns2));
+
+ if (ferror(f))
+ error("Write failed to %s: %m", _PATH_RESOLV);
+
+ fclose(f);
+}
+
+/*
+ * ipcp_printpkt - print the contents of an IPCP packet.
+ */
+static char *ipcp_codenames[] = {
+ "ConfReq", "ConfAck", "ConfNak", "ConfRej",
+ "TermReq", "TermAck", "CodeRej"
+};
+
+static int
+ipcp_printpkt(p, plen, printer, arg)
+ u_char *p;
+ int plen;
+ void (*printer) __P((void *, char *, ...));
+ void *arg;
+{
+ int code, id, len, olen;
+ u_char *pstart, *optend;
+ u_short cishort;
+ u_int32_t cilong;
+
+ if (plen < HEADERLEN)
+ return 0;
+ pstart = p;
+ GETCHAR(code, p);
+ GETCHAR(id, p);
+ GETSHORT(len, p);
+ if (len < HEADERLEN || len > plen)
+ return 0;
+
+ if (code >= 1 && code <= sizeof(ipcp_codenames) / sizeof(char *))
+ printer(arg, " %s", ipcp_codenames[code-1]);
+ else
+ printer(arg, " code=0x%x", code);
+ printer(arg, " id=0x%x", id);
+ len -= HEADERLEN;
+ switch (code) {
+ case CONFREQ:
+ case CONFACK:
+ case CONFNAK:
+ case CONFREJ:
+ /* print option list */
+ while (len >= 2) {
+ GETCHAR(code, p);
+ GETCHAR(olen, p);
+ p -= 2;
+ if (olen < 2 || olen > len) {
+ break;
+ }
+ printer(arg, " <");
+ len -= olen;
+ optend = p + olen;
+ switch (code) {
+ case CI_ADDRS:
+ if (olen == CILEN_ADDRS) {
+ p += 2;
+ GETLONG(cilong, p);
+ printer(arg, "addrs %I", htonl(cilong));
+ GETLONG(cilong, p);
+ printer(arg, " %I", htonl(cilong));
+ }
+ break;
+ case CI_COMPRESSTYPE:
+ if (olen >= CILEN_COMPRESS) {
+ p += 2;
+ GETSHORT(cishort, p);
+ printer(arg, "compress ");
+ switch (cishort) {
+ case IPCP_VJ_COMP:
+ printer(arg, "VJ");
+ break;
+ case IPCP_VJ_COMP_OLD:
+ printer(arg, "old-VJ");
+ break;
+ default:
+ printer(arg, "0x%x", cishort);
+ }
+ }
+ break;
+ case CI_ADDR:
+ if (olen == CILEN_ADDR) {
+ p += 2;
+ GETLONG(cilong, p);
+ printer(arg, "addr %I", htonl(cilong));
+ }
+ break;
+ case CI_MS_DNS1:
+ case CI_MS_DNS2:
+ p += 2;
+ GETLONG(cilong, p);
+ printer(arg, "ms-dns%d %I", code - CI_MS_DNS1 + 1,
+ htonl(cilong));
+ break;
+ case CI_MS_WINS1:
+ case CI_MS_WINS2:
+ p += 2;
+ GETLONG(cilong, p);
+ printer(arg, "ms-wins %I", htonl(cilong));
+ break;
+ }
+ while (p < optend) {
+ GETCHAR(code, p);
+ printer(arg, " %.2x", code);
+ }
+ printer(arg, ">");
+ }
+ break;
+
+ case TERMACK:
+ case TERMREQ:
+ if (len > 0 && *p >= ' ' && *p < 0x7f) {
+ printer(arg, " ");
+ print_string((char *)p, len, printer, arg);
+ p += len;
+ len = 0;
+ }
+ break;
+ }
+
+ /* print the rest of the bytes in the packet */
+ for (; len > 0; --len) {
+ GETCHAR(code, p);
+ printer(arg, " %.2x", code);
+ }
+
+ return p - pstart;
+}
+
+/*
+ * ip_active_pkt - see if this IP packet is worth bringing the link up for.
+ * We don't bring the link up for IP fragments or for TCP FIN packets
+ * with no data.
+ */
+#define IP_HDRLEN 20 /* bytes */
+#define IP_OFFMASK 0x1fff
+#define IPPROTO_TCP 6
+#define TCP_HDRLEN 20
+#define TH_FIN 0x01
+
+/*
+ * We use these macros because the IP header may be at an odd address,
+ * and some compilers might use word loads to get th_off or ip_hl.
+ */
+
+#define net_short(x) (((x)[0] << 8) + (x)[1])
+#define get_iphl(x) (((unsigned char *)(x))[0] & 0xF)
+#define get_ipoff(x) net_short((unsigned char *)(x) + 6)
+#define get_ipproto(x) (((unsigned char *)(x))[9])
+#define get_tcpoff(x) (((unsigned char *)(x))[12] >> 4)
+#define get_tcpflags(x) (((unsigned char *)(x))[13])
+
+static int
+ip_active_pkt(pkt, len)
+ u_char *pkt;
+ int len;
+{
+ u_char *tcp;
+ int hlen;
+
+ len -= PPP_HDRLEN;
+ pkt += PPP_HDRLEN;
+ if (len < IP_HDRLEN)
+ return 0;
+ if ((get_ipoff(pkt) & IP_OFFMASK) != 0)
+ return 0;
+ if (get_ipproto(pkt) != IPPROTO_TCP)
+ return 1;
+ hlen = get_iphl(pkt) * 4;
+ if (len < hlen + TCP_HDRLEN)
+ return 0;
+ tcp = pkt + hlen;
+ if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == hlen + get_tcpoff(tcp) * 4)
+ return 0;
+ return 1;