/* $NetBSD: ipcp.c,v 1.5 2021/01/09 16:39:28 christos Exp $ */ /* * ipcp.c - PPP IP Control Protocol. * * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The name "Carnegie Mellon University" must not be used to * endorse or promote products derived from this software without * prior written permission. For permission or any legal * details, please contact * Office of Technology Transfer * Carnegie Mellon University * 5000 Forbes Avenue * Pittsburgh, PA 15213-3890 * (412) 268-4387, fax: (412) 268-7395 * tech-transfer@andrew.cmu.edu * * 4. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Computing Services * at Carnegie Mellon University (http://www.cmu.edu/computing/)." * * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include __RCSID("$NetBSD: ipcp.c,v 1.5 2021/01/09 16:39:28 christos Exp $"); /* * TODO: */ #include #include #include #include #include #include #include #include #include #include #include "pppd.h" #include "fsm.h" #include "ipcp.h" #include "pathnames.h" /* global vars */ ipcp_options ipcp_wantoptions[NUM_PPP]; /* Options that we want to request */ ipcp_options ipcp_gotoptions[NUM_PPP]; /* Options that peer ack'd */ ipcp_options ipcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */ ipcp_options ipcp_hisoptions[NUM_PPP]; /* Options that we ack'd */ u_int32_t netmask = 0; /* IP netmask to set on interface */ bool disable_defaultip = 0; /* Don't use hostname for default IP adrs */ bool noremoteip = 0; /* Let him have no IP address */ /* Hook for a plugin to know when IP protocol has come up */ void (*ip_up_hook)(void) = NULL; /* Hook for a plugin to know when IP protocol has come down */ void (*ip_down_hook)(void) = NULL; /* Hook for a plugin to choose the remote IP address */ void (*ip_choose_hook)(u_int32_t *) = NULL; /* Notifiers for when IPCP goes up and down */ struct notifier *ip_up_notifier = NULL; struct notifier *ip_down_notifier = NULL; /* local vars */ static int default_route_set[NUM_PPP]; /* Have set up a default route */ static int proxy_arp_set[NUM_PPP]; /* Have created proxy arp entry */ static bool usepeerdns; /* Ask peer for DNS addrs */ static int ipcp_is_up; /* have called np_up() */ static int ipcp_is_open; /* haven't called np_finished() */ static bool ask_for_local; /* request our address from peer */ static char vj_value[8]; /* string form of vj option value */ static char netmask_str[20]; /* string form of netmask value */ /* * Callbacks for fsm code. (CI = Configuration Information) */ static void ipcp_resetci (fsm *); /* Reset our CI */ static int ipcp_cilen (fsm *); /* Return length of our CI */ static void ipcp_addci (fsm *, u_char *, int *); /* Add our CI */ static int ipcp_ackci (fsm *, u_char *, int); /* Peer ack'd our CI */ static int ipcp_nakci (fsm *, u_char *, int, int);/* Peer nak'd our CI */ static int ipcp_rejci (fsm *, u_char *, int); /* Peer rej'd our CI */ static int ipcp_reqci (fsm *, u_char *, int *, int); /* Rcv CI */ static void ipcp_up (fsm *); /* We're UP */ static void ipcp_down (fsm *); /* We're DOWN */ static void ipcp_finished (fsm *); /* Don't need lower layer */ fsm ipcp_fsm[NUM_PPP]; /* IPCP fsm structure */ static fsm_callbacks ipcp_callbacks = { /* IPCP callback routines */ ipcp_resetci, /* Reset our Configuration Information */ ipcp_cilen, /* Length of our Configuration Information */ ipcp_addci, /* Add our Configuration Information */ ipcp_ackci, /* ACK our Configuration Information */ ipcp_nakci, /* NAK our Configuration Information */ ipcp_rejci, /* Reject our Configuration Information */ ipcp_reqci, /* Request peer's Configuration Information */ ipcp_up, /* Called when fsm reaches OPENED state */ ipcp_down, /* Called when fsm leaves OPENED state */ NULL, /* Called when we want the lower layer up */ ipcp_finished, /* Called when we want the lower layer down */ NULL, /* Called when Protocol-Reject received */ NULL, /* Retransmission is necessary */ NULL, /* Called to handle protocol-specific codes */ "IPCP" /* String name of protocol */ }; /* * Command-line options. */ static int setvjslots (char **); static int setdnsaddr (char **); static int setwinsaddr (char **); static int setnetmask (char **); int setipaddr (char *, char **, int); static void printipaddr (option_t *, void (*)(void *, char *,...),void *); static option_t ipcp_option_list[] = { { "noip", o_bool, &ipcp_protent.enabled_flag, "Disable IP and IPCP" }, { "-ip", o_bool, &ipcp_protent.enabled_flag, "Disable IP and IPCP", OPT_ALIAS }, { "novj", o_bool, &ipcp_wantoptions[0].neg_vj, "Disable VJ compression", OPT_A2CLR, &ipcp_allowoptions[0].neg_vj }, { "-vj", o_bool, &ipcp_wantoptions[0].neg_vj, "Disable VJ compression", OPT_ALIAS | OPT_A2CLR, &ipcp_allowoptions[0].neg_vj }, { "novjccomp", o_bool, &ipcp_wantoptions[0].cflag, "Disable VJ connection-ID compression", OPT_A2CLR, &ipcp_allowoptions[0].cflag }, { "-vjccomp", o_bool, &ipcp_wantoptions[0].cflag, "Disable VJ connection-ID compression", OPT_ALIAS | OPT_A2CLR, &ipcp_allowoptions[0].cflag }, { "vj-max-slots", o_special, (void *)setvjslots, "Set maximum VJ header slots", OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, vj_value }, { "ipcp-accept-local", o_bool, &ipcp_wantoptions[0].accept_local, "Accept peer's address for us", 1 }, { "ipcp-accept-remote", o_bool, &ipcp_wantoptions[0].accept_remote, "Accept peer's address for it", 1 }, { "ipparam", o_string, &ipparam, "Set ip script parameter", OPT_PRIO }, { "noipdefault", o_bool, &disable_defaultip, "Don't use name for default IP adrs", 1 }, { "ms-dns", o_special, (void *)setdnsaddr, "DNS address for the peer's use", OPT_A2LIST }, { "ms-wins", o_special, (void *)setwinsaddr, "Nameserver for SMB over TCP/IP for peer", OPT_A2LIST }, { "ipcp-restart", o_int, &ipcp_fsm[0].timeouttime, "Set timeout for IPCP", OPT_PRIO }, { "ipcp-max-terminate", o_int, &ipcp_fsm[0].maxtermtransmits, "Set max #xmits for term-reqs", OPT_PRIO }, { "ipcp-max-configure", o_int, &ipcp_fsm[0].maxconfreqtransmits, "Set max #xmits for conf-reqs", OPT_PRIO }, { "ipcp-max-failure", o_int, &ipcp_fsm[0].maxnakloops, "Set max #conf-naks for IPCP", OPT_PRIO }, { "defaultroute", o_bool, &ipcp_wantoptions[0].default_route, "Add default route", OPT_ENABLE|1, &ipcp_allowoptions[0].default_route }, { "nodefaultroute", o_bool, &ipcp_allowoptions[0].default_route, "disable defaultroute option", OPT_A2CLR, &ipcp_wantoptions[0].default_route }, { "-defaultroute", o_bool, &ipcp_allowoptions[0].default_route, "disable defaultroute option", OPT_ALIAS | OPT_A2CLR, &ipcp_wantoptions[0].default_route }, #ifdef __linux__ { "replacedefaultroute", o_bool, &ipcp_wantoptions[0].replace_default_route, "Replace default route", OPT_PRIV | 1 }, { "noreplacedefaultroute", o_bool, &ipcp_wantoptions[0].replace_default_route, "Do not replace default route", 0 }, #endif { "proxyarp", o_bool, &ipcp_wantoptions[0].proxy_arp, "Add proxy ARP entry", OPT_ENABLE|1, &ipcp_allowoptions[0].proxy_arp }, { "noproxyarp", o_bool, &ipcp_allowoptions[0].proxy_arp, "disable proxyarp option", OPT_A2CLR, &ipcp_wantoptions[0].proxy_arp }, { "-proxyarp", o_bool, &ipcp_allowoptions[0].proxy_arp, "disable proxyarp option", OPT_ALIAS | OPT_A2CLR, &ipcp_wantoptions[0].proxy_arp }, { "usepeerdns", o_bool, &usepeerdns, "Ask peer for DNS address(es)", 1 }, { "netmask", o_special, (void *)setnetmask, "set netmask", OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, netmask_str }, { "ipcp-no-addresses", o_bool, &ipcp_wantoptions[0].old_addrs, "Disable old-style IP-Addresses usage", OPT_A2CLR, &ipcp_allowoptions[0].old_addrs }, { "ipcp-no-address", o_bool, &ipcp_wantoptions[0].neg_addr, "Disable IP-Address usage", OPT_A2CLR, &ipcp_allowoptions[0].neg_addr }, #ifdef __linux__ { "noremoteip", o_bool, &noremoteip, "Allow peer to have no IP address", 1 }, #endif { "nosendip", o_bool, &ipcp_wantoptions[0].neg_addr, "Don't send our IP address to peer", OPT_A2CLR, &ipcp_wantoptions[0].old_addrs}, { "IP addresses", o_wild, (void *) &setipaddr, "set local and remote IP addresses", OPT_NOARG | OPT_A2PRINTER, (void *) &printipaddr }, { NULL } }; /* * Protocol entry points from main code. */ static void ipcp_init (int); static void ipcp_open (int); static void ipcp_close (int, char *); static void ipcp_lowerup (int); static void ipcp_lowerdown (int); static void ipcp_input (int, u_char *, int); static void ipcp_protrej (int); static int ipcp_printpkt (u_char *, int, void (*) (void *, char *, ...), void *); static void ip_check_options (void); static int ip_demand_conf (int); static int ip_active_pkt (u_char *, int); static void create_resolv (u_int32_t, u_int32_t); struct protent ipcp_protent = { PPP_IPCP, ipcp_init, ipcp_input, ipcp_protrej, ipcp_lowerup, ipcp_lowerdown, ipcp_open, ipcp_close, ipcp_printpkt, NULL, 1, "IPCP", "IP", ipcp_option_list, ip_check_options, ip_demand_conf, ip_active_pkt }; static void ipcp_clear_addrs (int, u_int32_t, u_int32_t, bool); static void ipcp_script (char *, int); /* Run an up/down script */ static void ipcp_script_done (void *); /* * Lengths of configuration options. */ #define CILEN_VOID 2 #define CILEN_COMPRESS 4 /* min length for compression protocol opt. */ #define CILEN_VJ 6 /* length for RFC1332 Van-Jacobson opt. */ #define CILEN_ADDR 6 /* new-style single address option */ #define CILEN_ADDRS 10 /* old-style dual address option */ #define CODENAME(x) ((x) == CONFACK ? "ACK" : \ (x) == CONFNAK ? "NAK" : "REJ") /* * This state variable is used to ensure that we don't * run an ipcp-up/down script while one is already running. */ static enum script_state { s_down, s_up, } ipcp_script_state; static pid_t ipcp_script_pid; /* * Make a string representation of a network IP address. */ char * ip_ntoa(u_int32_t ipaddr) { static char b[64]; slprintf(b, sizeof(b), "%I", ipaddr); return b; } /* * Option parsing. */ /* * setvjslots - set maximum number of connection slots for VJ compression */ static int setvjslots(char **argv) { int value; if (!int_option(*argv, &value)) return 0; if (value < 2 || value > 16) { option_error("vj-max-slots value must be between 2 and 16"); return 0; } ipcp_wantoptions [0].maxslotindex = ipcp_allowoptions[0].maxslotindex = value - 1; slprintf(vj_value, sizeof(vj_value), "%d", value); return 1; } /* * setdnsaddr - set the dns address(es) */ static int setdnsaddr(char **argv) { u_int32_t dns; struct hostent *hp; dns = inet_addr(*argv); if (dns == (u_int32_t) -1) { if ((hp = gethostbyname(*argv)) == NULL) { option_error("invalid address parameter '%s' for ms-dns option", *argv); return 0; } dns = *(u_int32_t *)hp->h_addr; } /* We take the last 2 values given, the 2nd-last as the primary and the last as the secondary. If only one is given it becomes both primary and secondary. */ if (ipcp_allowoptions[0].dnsaddr[1] == 0) ipcp_allowoptions[0].dnsaddr[0] = dns; else ipcp_allowoptions[0].dnsaddr[0] = ipcp_allowoptions[0].dnsaddr[1]; /* always set the secondary address value. */ ipcp_allowoptions[0].dnsaddr[1] = dns; return (1); } /* * setwinsaddr - set the wins address(es) * This is primrarly used with the Samba package under UNIX or for pointing * the caller to the existing WINS server on a Windows NT platform. */ static int setwinsaddr(char **argv) { u_int32_t wins; struct hostent *hp; wins = inet_addr(*argv); if (wins == (u_int32_t) -1) { if ((hp = gethostbyname(*argv)) == NULL) { option_error("invalid address parameter '%s' for ms-wins option", *argv); return 0; } wins = *(u_int32_t *)hp->h_addr; } /* We take the last 2 values given, the 2nd-last as the primary and the last as the secondary. If only one is given it becomes both primary and secondary. */ if (ipcp_allowoptions[0].winsaddr[1] == 0) ipcp_allowoptions[0].winsaddr[0] = wins; else ipcp_allowoptions[0].winsaddr[0] = ipcp_allowoptions[0].winsaddr[1]; /* always set the secondary address value. */ ipcp_allowoptions[0].winsaddr[1] = wins; return (1); } /* * setipaddr - Set the IP address * If doit is 0, the call is to check whether this option is * potentially an IP address specification. * Not static so that plugins can call it to set the addresses */ int setipaddr(char *arg, char **argv, int doit) { struct hostent *hp; char *colon; u_int32_t local, remote; ipcp_options *wo = &ipcp_wantoptions[0]; static int prio_local = 0, prio_remote = 0; /* * IP address pair separated by ":". */ if ((colon = strchr(arg, ':')) == NULL) return 0; if (!doit) return 1; /* * If colon first character, then no local addr. */ if (colon != arg && option_priority >= prio_local) { *colon = '\0'; if ((local = inet_addr(arg)) == (u_int32_t) -1) { if ((hp = gethostbyname(arg)) == NULL) { option_error("unknown host: %s", arg); return 0; } local = *(u_int32_t *)hp->h_addr; } if (bad_ip_adrs(local)) { option_error("bad local IP address %s", ip_ntoa(local)); return 0; } if (local != 0) wo->ouraddr = local; *colon = ':'; prio_local = option_priority; } /* * If colon last character, then no remote addr. */ if (*++colon != '\0' && option_priority >= prio_remote) { if ((remote = inet_addr(colon)) == (u_int32_t) -1) { if ((hp = gethostbyname(colon)) == NULL) { option_error("unknown host: %s", colon); return 0; } remote = *(u_int32_t *)hp->h_addr; if (remote_name[0] == 0) strlcpy(remote_name, colon, sizeof(remote_name)); } if (bad_ip_adrs(remote)) { option_error("bad remote IP address %s", ip_ntoa(remote)); return 0; } if (remote != 0) wo->hisaddr = remote; prio_remote = option_priority; } return 1; } static void printipaddr(option_t *opt, void (*printer) (void *, char *, ...), void *arg) { ipcp_options *wo = &ipcp_wantoptions[0]; if (wo->ouraddr != 0) printer(arg, "%I", wo->ouraddr); printer(arg, ":"); if (wo->hisaddr != 0) printer(arg, "%I", wo->hisaddr); } /* * setnetmask - set the netmask to be used on the interface. */ static int setnetmask(char **argv) { u_int32_t mask; int n; char *p; /* * Unfortunately, if we use inet_addr, we can't tell whether * a result of all 1s is an error or a valid 255.255.255.255. */ p = *argv; n = parse_dotted_ip(p, &mask); mask = htonl(mask); if (n == 0 || p[n] != 0 || (netmask & ~mask) != 0) { option_error("invalid netmask value '%s'", *argv); return 0; } netmask = mask; slprintf(netmask_str, sizeof(netmask_str), "%I", mask); return (1); } int parse_dotted_ip(char *p, u_int32_t *vp) { int n; u_int32_t v, b; char *endp, *p0 = p; v = 0; for (n = 3;; --n) { b = strtoul(p, &endp, 0); if (endp == p) return 0; if (b > 255) { if (n < 3) return 0; /* accept e.g. 0xffffff00 */ *vp = b; return endp - p0; } v |= b << (n * 8); p = endp; if (n == 0) break; if (*p != '.') return 0; ++p; } *vp = v; return p - p0; } /* * ipcp_init - Initialize IPCP. */ static void ipcp_init(int unit) { fsm *f = &ipcp_fsm[unit]; ipcp_options *wo = &ipcp_wantoptions[unit]; ipcp_options *ao = &ipcp_allowoptions[unit]; f->unit = unit; f->protocol = PPP_IPCP; f->callbacks = &ipcp_callbacks; fsm_init(&ipcp_fsm[unit]); /* * Some 3G modems use repeated IPCP NAKs as a way of stalling * until they can contact a server on the network, so we increase * the default number of NAKs we accept before we start treating * them as rejects. */ f->maxnakloops = 100; memset(wo, 0, sizeof(*wo)); memset(ao, 0, sizeof(*ao)); wo->neg_addr = wo->old_addrs = 1; wo->neg_vj = 1; wo->vj_protocol = IPCP_VJ_COMP; wo->maxslotindex = MAX_STATES - 1; /* really max index */ wo->cflag = 1; /* max slots and slot-id compression are currently hardwired in */ /* ppp_if.c to 16 and 1, this needs to be changed (among other */ /* things) gmc */ ao->neg_addr = ao->old_addrs = 1; ao->neg_vj = 1; ao->maxslotindex = MAX_STATES - 1; ao->cflag = 1; /* * XXX These control whether the user may use the proxyarp * and defaultroute options. */ ao->proxy_arp = 1; ao->default_route = 1; } /* * ipcp_open - IPCP is allowed to come up. */ static void ipcp_open(int unit) { fsm_open(&ipcp_fsm[unit]); ipcp_is_open = 1; } /* * ipcp_close - Take IPCP down. */ static void ipcp_close(int unit, char *reason) { fsm_close(&ipcp_fsm[unit], reason); } /* * ipcp_lowerup - The lower layer is up. */ static void ipcp_lowerup(int unit) { fsm_lowerup(&ipcp_fsm[unit]); } /* * ipcp_lowerdown - The lower layer is down. */ static void ipcp_lowerdown(int unit) { fsm_lowerdown(&ipcp_fsm[unit]); } /* * ipcp_input - Input IPCP packet. */ static void ipcp_input(int unit, u_char *p, int len) { fsm_input(&ipcp_fsm[unit], p, len); } /* * ipcp_protrej - A Protocol-Reject was received for IPCP. * * Pretend the lower layer went down, so we shut up. */ static void ipcp_protrej(int unit) { fsm_lowerdown(&ipcp_fsm[unit]); } /* * ipcp_resetci - Reset our CI. * Called by fsm_sconfreq, Send Configure Request. */ static void ipcp_resetci(fsm *f) { ipcp_options *wo = &ipcp_wantoptions[f->unit]; ipcp_options *go = &ipcp_gotoptions[f->unit]; ipcp_options *ao = &ipcp_allowoptions[f->unit]; wo->req_addr = (wo->neg_addr || wo->old_addrs) && (ao->neg_addr || ao->old_addrs); if (wo->ouraddr == 0) wo->accept_local = 1; if (wo->hisaddr == 0) wo->accept_remote = 1; wo->req_dns1 = usepeerdns; /* Request DNS addresses from the peer */ wo->req_dns2 = usepeerdns; *go = *wo; if (!ask_for_local) go->ouraddr = 0; if (ip_choose_hook) { ip_choose_hook(&wo->hisaddr); if (wo->hisaddr) { wo->accept_remote = 0; } } BZERO(&ipcp_hisoptions[f->unit], sizeof(ipcp_options)); } /* * ipcp_cilen - Return length of our CI. * Called by fsm_sconfreq, Send Configure Request. */ static int ipcp_cilen(fsm *f) { ipcp_options *go = &ipcp_gotoptions[f->unit]; ipcp_options *wo = &ipcp_wantoptions[f->unit]; ipcp_options *ho = &ipcp_hisoptions[f->unit]; #define LENCIADDRS(neg) (neg ? CILEN_ADDRS : 0) #define LENCIVJ(neg, old) (neg ? (old? CILEN_COMPRESS : CILEN_VJ) : 0) #define LENCIADDR(neg) (neg ? CILEN_ADDR : 0) #define LENCIDNS(neg) LENCIADDR(neg) #define LENCIWINS(neg) LENCIADDR(neg) /* * First see if we want to change our options to the old * forms because we have received old forms from the peer. */ if (go->neg_addr && go->old_addrs && !ho->neg_addr && ho->old_addrs) go->neg_addr = 0; if (wo->neg_vj && !go->neg_vj && !go->old_vj) { /* try an older style of VJ negotiation */ /* use the old style only if the peer did */ if (ho->neg_vj && ho->old_vj) { go->neg_vj = 1; go->old_vj = 1; go->vj_protocol = ho->vj_protocol; } } return (LENCIADDRS(!go->neg_addr && go->old_addrs) + LENCIVJ(go->neg_vj, go->old_vj) + LENCIADDR(go->neg_addr) + LENCIDNS(go->req_dns1) + LENCIDNS(go->req_dns2) + LENCIWINS(go->winsaddr[0]) + LENCIWINS(go->winsaddr[1])) ; } /* * ipcp_addci - Add our desired CIs to a packet. * Called by fsm_sconfreq, Send Configure Request. */ static void ipcp_addci(fsm *f, u_char *ucp, int *lenp) { ipcp_options *go = &ipcp_gotoptions[f->unit]; int len = *lenp; #define ADDCIADDRS(opt, neg, val1, val2) \ if (neg) { \ if (len >= CILEN_ADDRS) { \ u_int32_t l; \ PUTCHAR(opt, ucp); \ PUTCHAR(CILEN_ADDRS, ucp); \ l = ntohl(val1); \ PUTLONG(l, ucp); \ l = ntohl(val2); \ PUTLONG(l, ucp); \ len -= CILEN_ADDRS; \ } else \ go->old_addrs = 0; \ } #define ADDCIVJ(opt, neg, val, old, maxslotindex, cflag) \ if (neg) { \ int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \ if (len >= vjlen) { \ PUTCHAR(opt, ucp); \ PUTCHAR(vjlen, ucp); \ PUTSHORT(val, ucp); \ if (!old) { \ PUTCHAR(maxslotindex, ucp); \ PUTCHAR(cflag, ucp); \ } \ len -= vjlen; \ } else \ neg = 0; \ } #define ADDCIADDR(opt, neg, val) \ if (neg) { \ if (len >= CILEN_ADDR) { \ u_int32_t l; \ PUTCHAR(opt, ucp); \ PUTCHAR(CILEN_ADDR, ucp); \ l = ntohl(val); \ PUTLONG(l, ucp); \ len -= CILEN_ADDR; \ } else \ neg = 0; \ } #define ADDCIDNS(opt, neg, addr) \ if (neg) { \ if (len >= CILEN_ADDR) { \ u_int32_t l; \ PUTCHAR(opt, ucp); \ PUTCHAR(CILEN_ADDR, ucp); \ l = ntohl(addr); \ PUTLONG(l, ucp); \ len -= CILEN_ADDR; \ } else \ neg = 0; \ } #define ADDCIWINS(opt, addr) \ if (addr) { \ if (len >= CILEN_ADDR) { \ u_int32_t l; \ PUTCHAR(opt, ucp); \ PUTCHAR(CILEN_ADDR, ucp); \ l = ntohl(addr); \ PUTLONG(l, ucp); \ len -= CILEN_ADDR; \ } else \ addr = 0; \ } ADDCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr, go->hisaddr); ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj, go->maxslotindex, go->cflag); ADDCIADDR(CI_ADDR, go->neg_addr, go->ouraddr); ADDCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]); ADDCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]); ADDCIWINS(CI_MS_WINS1, go->winsaddr[0]); ADDCIWINS(CI_MS_WINS2, go->winsaddr[1]); *lenp -= len; } /* * ipcp_ackci - Ack our CIs. * Called by fsm_rconfack, Receive Configure ACK. * * Returns: * 0 - Ack was bad. * 1 - Ack was good. */ static int ipcp_ackci(fsm *f, u_char *p, int len) { ipcp_options *go = &ipcp_gotoptions[f->unit]; u_short cilen, citype, cishort; u_int32_t cilong; u_char cimaxslotindex, cicflag; /* * CIs must be in exactly the same order that we sent... * Check packet length and CI length at each step. * If we find any deviations, then this packet is bad. */ #define ACKCIADDRS(opt, neg, val1, val2) \ if (neg) { \ u_int32_t l; \ if ((len -= CILEN_ADDRS) < 0) \ goto bad; \ GETCHAR(citype, p); \ GETCHAR(cilen, p); \ if (cilen != CILEN_ADDRS || \ citype != opt) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ if (val1 != cilong) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ if (val2 != cilong) \ goto bad; \ } #define ACKCIVJ(opt, neg, val, old, maxslotindex, cflag) \ if (neg) { \ int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \ if ((len -= vjlen) < 0) \ goto bad; \ GETCHAR(citype, p); \ GETCHAR(cilen, p); \ if (cilen != vjlen || \ citype != opt) \ goto bad; \ GETSHORT(cishort, p); \ if (cishort != val) \ goto bad; \ if (!old) { \ GETCHAR(cimaxslotindex, p); \ if (cimaxslotindex != maxslotindex) \ goto bad; \ GETCHAR(cicflag, p); \ if (cicflag != cflag) \ goto bad; \ } \ } #define ACKCIADDR(opt, neg, val) \ if (neg) { \ u_int32_t l; \ if ((len -= CILEN_ADDR) < 0) \ goto bad; \ GETCHAR(citype, p); \ GETCHAR(cilen, p); \ if (cilen != CILEN_ADDR || \ citype != opt) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ if (val != cilong) \ goto bad; \ } #define ACKCIDNS(opt, neg, addr) \ if (neg) { \ u_int32_t l; \ if ((len -= CILEN_ADDR) < 0) \ goto bad; \ GETCHAR(citype, p); \ GETCHAR(cilen, p); \ if (cilen != CILEN_ADDR || citype != opt) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ if (addr != cilong) \ goto bad; \ } #define ACKCIWINS(opt, addr) \ if (addr) { \ u_int32_t l; \ if ((len -= CILEN_ADDR) < 0) \ goto bad; \ GETCHAR(citype, p); \ GETCHAR(cilen, p); \ if (cilen != CILEN_ADDR || citype != opt) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ if (addr != cilong) \ goto bad; \ } ACKCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr, go->hisaddr); ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj, go->maxslotindex, go->cflag); ACKCIADDR(CI_ADDR, go->neg_addr, go->ouraddr); ACKCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]); ACKCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]); ACKCIWINS(CI_MS_WINS1, go->winsaddr[0]); ACKCIWINS(CI_MS_WINS2, go->winsaddr[1]); /* * If there are any remaining CIs, then this packet is bad. */ if (len != 0) goto bad; return (1); bad: IPCPDEBUG(("ipcp_ackci: received bad Ack!")); return (0); } /* * ipcp_nakci - Peer has sent a NAK for some of our CIs. * This should not modify any state if the Nak is bad * or if IPCP is in the OPENED state. * Calback from fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject. * * Returns: * 0 - Nak was bad. * 1 - Nak was good. */ static int ipcp_nakci(fsm *f, u_char *p, int len, int treat_as_reject) { ipcp_options *go = &ipcp_gotoptions[f->unit]; u_char cimaxslotindex, cicflag; u_char citype, cilen, *next; u_short cishort; u_int32_t ciaddr1, ciaddr2, l, cidnsaddr; ipcp_options no; /* options we've seen Naks for */ ipcp_options try; /* options to request next time */ BZERO(&no, sizeof(no)); try = *go; /* * Any Nak'd CIs must be in exactly the same order that we sent. * Check packet length and CI length at each step. * If we find any deviations, then this packet is bad. */ #define NAKCIADDRS(opt, neg, code) \ if ((neg) && \ (cilen = p[1]) == CILEN_ADDRS && \ len >= cilen && \ p[0] == opt) { \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ ciaddr1 = htonl(l); \ GETLONG(l, p); \ ciaddr2 = htonl(l); \ no.old_addrs = 1; \ code \ } #define NAKCIVJ(opt, neg, code) \ if (go->neg && \ ((cilen = p[1]) == CILEN_COMPRESS || cilen == CILEN_VJ) && \ len >= cilen && \ p[0] == opt) { \ len -= cilen; \ INCPTR(2, p); \ GETSHORT(cishort, p); \ no.neg = 1; \ code \ } #define NAKCIADDR(opt, neg, code) \ if (go->neg && \ (cilen = p[1]) == CILEN_ADDR && \ len >= cilen && \ p[0] == opt) { \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ ciaddr1 = htonl(l); \ no.neg = 1; \ code \ } #define NAKCIDNS(opt, neg, code) \ if (go->neg && \ ((cilen = p[1]) == CILEN_ADDR) && \ len >= cilen && \ p[0] == opt) { \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ cidnsaddr = htonl(l); \ no.neg = 1; \ code \ } /* * Accept the peer's idea of {our,his} address, if different * from our idea, only if the accept_{local,remote} flag is set. */ NAKCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, if (treat_as_reject) { try.old_addrs = 0; } else { if (go->accept_local && ciaddr1) { /* take his idea of our address */ try.ouraddr = ciaddr1; } if (go->accept_remote && ciaddr2) { /* take his idea of his address */ try.hisaddr = ciaddr2; } } ); /* * Accept the peer's value of maxslotindex provided that it * is less than what we asked for. Turn off slot-ID compression * if the peer wants. Send old-style compress-type option if * the peer wants. */ NAKCIVJ(CI_COMPRESSTYPE, neg_vj, if (treat_as_reject) { try.neg_vj = 0; } else if (cilen == CILEN_VJ) { GETCHAR(cimaxslotindex, p); GETCHAR(cicflag, p); if (cishort == IPCP_VJ_COMP) { try.old_vj = 0; if (cimaxslotindex < go->maxslotindex) try.maxslotindex = cimaxslotindex; if (!cicflag) try.cflag = 0; } else { try.neg_vj = 0; } } else { if (cishort == IPCP_VJ_COMP || cishort == IPCP_VJ_COMP_OLD) { try.old_vj = 1; try.vj_protocol = cishort; } else { try.neg_vj = 0; } } ); NAKCIADDR(CI_ADDR, neg_addr, if (treat_as_reject) { try.neg_addr = 0; try.old_addrs = 0; } else if (go->accept_local && ciaddr1) { /* take his idea of our address */ try.ouraddr = ciaddr1; } ); NAKCIDNS(CI_MS_DNS1, req_dns1, if (treat_as_reject) { try.req_dns1 = 0; } else { try.dnsaddr[0] = cidnsaddr; } ); NAKCIDNS(CI_MS_DNS2, req_dns2, if (treat_as_reject) { try.req_dns2 = 0; } else { try.dnsaddr[1] = cidnsaddr; } ); /* * There may be remaining CIs, if the peer is requesting negotiation * on an option that we didn't include in our request packet. * If they want to negotiate about IP addresses, we comply. * If they want us to ask for compression, we refuse. * If they want us to ask for ms-dns, we do that, since some * peers get huffy if we don't. */ while (len >= CILEN_VOID) { GETCHAR(citype, p); GETCHAR(cilen, p); if ( cilen < CILEN_VOID || (len -= cilen) < 0 ) goto bad; next = p + cilen - 2; switch (citype) { case CI_COMPRESSTYPE: if (go->neg_vj || no.neg_vj || (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) goto bad; no.neg_vj = 1; break; case CI_ADDRS: if ((!go->neg_addr && go->old_addrs) || no.old_addrs || cilen != CILEN_ADDRS) goto bad; try.neg_addr = 0; GETLONG(l, p); ciaddr1 = htonl(l); if (ciaddr1 && go->accept_local) try.ouraddr = ciaddr1; GETLONG(l, p); ciaddr2 = htonl(l); if (ciaddr2 && go->accept_remote) try.hisaddr = ciaddr2; no.old_addrs = 1; break; case CI_ADDR: if (go->neg_addr || no.neg_addr || cilen != CILEN_ADDR) goto bad; try.old_addrs = 0; GETLONG(l, p); ciaddr1 = htonl(l); if (ciaddr1 && go->accept_local) try.ouraddr = ciaddr1; if (try.ouraddr != 0) try.neg_addr = 1; no.neg_addr = 1; break; case CI_MS_DNS1: if (go->req_dns1 || no.req_dns1 || cilen != CILEN_ADDR) goto bad; GETLONG(l, p); try.dnsaddr[0] = htonl(l); try.req_dns1 = 1; no.req_dns1 = 1; break; case CI_MS_DNS2: if (go->req_dns2 || no.req_dns2 || cilen != CILEN_ADDR) goto bad; GETLONG(l, p); try.dnsaddr[1] = htonl(l); try.req_dns2 = 1; no.req_dns2 = 1; break; case CI_MS_WINS1: case CI_MS_WINS2: if (cilen != CILEN_ADDR) goto bad; GETLONG(l, p); ciaddr1 = htonl(l); if (ciaddr1) try.winsaddr[citype == CI_MS_WINS2] = ciaddr1; break; } p = next; } /* * OK, the Nak is good. Now we can update state. * If there are any remaining options, we ignore them. */ if (f->state != OPENED) *go = try; return 1; bad: IPCPDEBUG(("ipcp_nakci: received bad Nak!")); return 0; } /* * ipcp_rejci - Reject some of our CIs. * Callback from fsm_rconfnakrej. */ static int ipcp_rejci(fsm *f, u_char *p, int len) { ipcp_options *go = &ipcp_gotoptions[f->unit]; u_char cimaxslotindex, ciflag, cilen; u_short cishort; u_int32_t cilong; ipcp_options try; /* options to request next time */ try = *go; /* * Any Rejected CIs must be in exactly the same order that we sent. * Check packet length and CI length at each step. * If we find any deviations, then this packet is bad. */ #define REJCIADDRS(opt, neg, val1, val2) \ if ((neg) && \ (cilen = p[1]) == CILEN_ADDRS && \ len >= cilen && \ p[0] == opt) { \ u_int32_t l; \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ cilong = htonl(l); \ /* Check rejected value. */ \ if (cilong != val1) \ goto bad; \ GETLONG(l, p); \ cilong = htonl(l); \ /* Check rejected value. */ \ if (cilong != val2) \ goto bad; \ try.old_addrs = 0; \ } #define REJCIVJ(opt, neg, val, old, maxslot, cflag) \ if (go->neg && \ p[1] == (old? CILEN_COMPRESS : CILEN_VJ) && \ len >= p[1] && \ p[0] == opt) { \ len -= p[1]; \ INCPTR(2, p); \ GETSHORT(cishort, p); \ /* Check rejected value. */ \ if (cishort != val) \ goto bad; \ if (!old) { \ GETCHAR(cimaxslotindex, p); \ if (cimaxslotindex != maxslot) \ goto bad; \ GETCHAR(ciflag, p); \ if (ciflag != cflag) \ goto bad; \ } \ try.neg = 0; \ } #define REJCIADDR(opt, neg, val) \ if (go->neg && \ (cilen = p[1]) == CILEN_ADDR && \ len >= cilen && \ p[0] == opt) { \ u_int32_t l; \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ cilong = htonl(l); \ /* Check rejected value. */ \ if (cilong != val) \ goto bad; \ try.neg = 0; \ } #define REJCIDNS(opt, neg, dnsaddr) \ if (go->neg && \ ((cilen = p[1]) == CILEN_ADDR) && \ len >= cilen && \ p[0] == opt) { \ u_int32_t l; \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ cilong = htonl(l); \ /* Check rejected value. */ \ if (cilong != dnsaddr) \ goto bad; \ try.neg = 0; \ } #define REJCIWINS(opt, addr) \ if (addr && \ ((cilen = p[1]) == CILEN_ADDR) && \ len >= cilen && \ p[0] == opt) { \ u_int32_t l; \ len -= cilen; \ INCPTR(2, p); \ GETLONG(l, p); \ cilong = htonl(l); \ /* Check rejected value. */ \ if (cilong != addr) \ goto bad; \ try.winsaddr[opt == CI_MS_WINS2] = 0; \ } REJCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr, go->hisaddr); REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol, go->old_vj, go->maxslotindex, go->cflag); REJCIADDR(CI_ADDR, neg_addr, go->ouraddr); REJCIDNS(CI_MS_DNS1, req_dns1, go->dnsaddr[0]); REJCIDNS(CI_MS_DNS2, req_dns2, go->dnsaddr[1]); REJCIWINS(CI_MS_WINS1, go->winsaddr[0]); REJCIWINS(CI_MS_WINS2, go->winsaddr[1]); /* * If there are any remaining CIs, then this packet is bad. */ if (len != 0) goto bad; /* * Now we can update state. */ if (f->state != OPENED) *go = try; return 1; bad: IPCPDEBUG(("ipcp_rejci: received bad Reject!")); return 0; } /* * ipcp_reqci - Check the peer's requested CIs and send appropriate response. * Callback from fsm_rconfreq, Receive Configure Request * * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified * appropriately. If reject_if_disagree is non-zero, doesn't return * CONFNAK; returns CONFREJ if it can't return CONFACK. */ static int ipcp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree) { ipcp_options *wo = &ipcp_wantoptions[f->unit]; ipcp_options *ho = &ipcp_hisoptions[f->unit]; ipcp_options *ao = &ipcp_allowoptions[f->unit]; u_char *cip, *next; /* Pointer to current and next CIs */ u_short cilen, citype; /* Parsed len, type */ u_short cishort; /* Parsed short value */ u_int32_t tl, ciaddr1, ciaddr2;/* Parsed address values */ int rc = CONFACK; /* Final packet return code */ int orc; /* Individual option return code */ u_char *p; /* Pointer to next char to parse */ u_char *ucp = inp; /* Pointer to current output char */ int l = *len; /* Length left */ u_char maxslotindex, cflag; int d; /* * Reset all his options. */ BZERO(ho, sizeof(*ho)); /* * Process all his options. */ next = inp; while (l) { orc = CONFACK; /* Assume success */ cip = p = next; /* Remember begining of CI */ if (l < 2 || /* Not enough data for CI header or */ p[1] < 2 || /* CI length too small or */ p[1] > l) { /* CI length too big? */ IPCPDEBUG(("ipcp_reqci: bad CI length!")); orc = CONFREJ; /* Reject bad CI */ cilen = l; /* Reject till end of packet */ l = 0; /* Don't loop again */ goto endswitch; } GETCHAR(citype, p); /* Parse CI type */ GETCHAR(cilen, p); /* Parse CI length */ l -= cilen; /* Adjust remaining length */ next += cilen; /* Step to next CI */ switch (citype) { /* Check CI type */ case CI_ADDRS: if (!ao->old_addrs || ho->neg_addr || cilen != CILEN_ADDRS) { /* Check CI length */ orc = CONFREJ; /* Reject CI */ break; } /* * If he has no address, or if we both have his address but * disagree about it, then NAK it with our idea. * In particular, if we don't know his address, but he does, * then accept it. */ GETLONG(tl, p); /* Parse source address (his) */ ciaddr1 = htonl(tl); if (ciaddr1 != wo->hisaddr && (ciaddr1 == 0 || !wo->accept_remote)) { orc = CONFNAK; if (!reject_if_disagree) { DECPTR(sizeof(u_int32_t), p); tl = ntohl(wo->hisaddr); PUTLONG(tl, p); } } else if (ciaddr1 == 0 && wo->hisaddr == 0) { /* * If neither we nor he knows his address, reject the option. */ orc = CONFREJ; wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */ break; } /* * If he doesn't know our address, or if we both have our address * but disagree about it, then NAK it with our idea. */ GETLONG(tl, p); /* Parse desination address (ours) */ ciaddr2 = htonl(tl); if (ciaddr2 != wo->ouraddr) { if (ciaddr2 == 0 || !wo->accept_local) { orc = CONFNAK; if (!reject_if_disagree) { DECPTR(sizeof(u_int32_t), p); tl = ntohl(wo->ouraddr); PUTLONG(tl, p); } } else { wo->ouraddr = ciaddr2; /* accept peer's idea */ } } ho->old_addrs = 1; ho->hisaddr = ciaddr1; ho->ouraddr = ciaddr2; break; case CI_ADDR: if (!ao->neg_addr || ho->old_addrs || cilen != CILEN_ADDR) { /* Check CI length */ orc = CONFREJ; /* Reject CI */ break; } /* * If he has no address, or if we both have his address but * disagree about it, then NAK it with our idea. * In particular, if we don't know his address, but he does, * then accept it. */ GETLONG(tl, p); /* Parse source address (his) */ ciaddr1 = htonl(tl); if (ciaddr1 != wo->hisaddr && (ciaddr1 == 0 || !wo->accept_remote)) { orc = CONFNAK; if (!reject_if_disagree) { DECPTR(sizeof(u_int32_t), p); tl = ntohl(wo->hisaddr); PUTLONG(tl, p); } } else if (ciaddr1 == 0 && wo->hisaddr == 0) { /* * Don't ACK an address of 0.0.0.0 - reject it instead. */ orc = CONFREJ; wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */ break; } ho->neg_addr = 1; ho->hisaddr = ciaddr1; break; case CI_MS_DNS1: case CI_MS_DNS2: /* Microsoft primary or secondary DNS request */ d = citype == CI_MS_DNS2; /* If we do not have a DNS address then we cannot send it */ if (ao->dnsaddr[d] == 0 || cilen != CILEN_ADDR) { /* Check CI length */ orc = CONFREJ; /* Reject CI */ break; } GETLONG(tl, p); if (htonl(tl) != ao->dnsaddr[d]) { DECPTR(sizeof(u_int32_t), p); tl = ntohl(ao->dnsaddr[d]); PUTLONG(tl, p); orc = CONFNAK; } break; case CI_MS_WINS1: case CI_MS_WINS2: /* Microsoft primary or secondary WINS request */ d = citype == CI_MS_WINS2; /* If we do not have a DNS address then we cannot send it */ if (ao->winsaddr[d] == 0 || cilen != CILEN_ADDR) { /* Check CI length */ orc = CONFREJ; /* Reject CI */ break; } GETLONG(tl, p); if (htonl(tl) != ao->winsaddr[d]) { DECPTR(sizeof(u_int32_t), p); tl = ntohl(ao->winsaddr[d]); PUTLONG(tl, p); orc = CONFNAK; } break; case CI_COMPRESSTYPE: if (!ao->neg_vj || (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) { orc = CONFREJ; break; } GETSHORT(cishort, p); if (!(cishort == IPCP_VJ_COMP || (cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) { orc = CONFREJ; break; } ho->neg_vj = 1; ho->vj_protocol = cishort; if (cilen == CILEN_VJ) { GETCHAR(maxslotindex, p); if (maxslotindex > ao->maxslotindex) { orc = CONFNAK; if (!reject_if_disagree){ DECPTR(1, p); PUTCHAR(ao->maxslotindex, p); } } GETCHAR(cflag, p); if (cflag && !ao->cflag) { orc = CONFNAK; if (!reject_if_disagree){ DECPTR(1, p); PUTCHAR(wo->cflag, p); } } ho->maxslotindex = maxslotindex; ho->cflag = cflag; } else { ho->old_vj = 1; ho->maxslotindex = MAX_STATES - 1; ho->cflag = 1; } break; default: orc = CONFREJ; break; } endswitch: if (orc == CONFACK && /* Good CI */ rc != CONFACK) /* but prior CI wasnt? */ continue; /* Don't send this one */ if (orc == CONFNAK) { /* Nak this CI? */ if (reject_if_disagree) /* Getting fed up with sending NAKs? */ orc = CONFREJ; /* Get tough if so */ else { if (rc == CONFREJ) /* Rejecting prior CI? */ continue; /* Don't send this one */ if (rc == CONFACK) { /* Ack'd all prior CIs? */ rc = CONFNAK; /* Not anymore... */ ucp = inp; /* Backup */ } } } if (orc == CONFREJ && /* Reject this CI */ rc != CONFREJ) { /* but no prior ones? */ rc = CONFREJ; ucp = inp; /* Backup */ } /* Need to move CI? */ if (ucp != cip) BCOPY(cip, ucp, cilen); /* Move it */ /* Update output pointer */ INCPTR(cilen, ucp); } /* * If we aren't rejecting this packet, and we want to negotiate * their address, and they didn't send their address, then we * send a NAK with a CI_ADDR option appended. We assume the * input buffer is long enough that we can append the extra * option safely. */ if (rc != CONFREJ && !ho->neg_addr && !ho->old_addrs && wo->req_addr && !reject_if_disagree && !noremoteip) { if (rc == CONFACK) { rc = CONFNAK; ucp = inp; /* reset pointer */ wo->req_addr = 0; /* don't ask again */ } PUTCHAR(CI_ADDR, ucp); PUTCHAR(CILEN_ADDR, ucp); tl = ntohl(wo->hisaddr); PUTLONG(tl, ucp); } *len = ucp - inp; /* Compute output length */ IPCPDEBUG(("ipcp: returning Configure-%s", CODENAME(rc))); return (rc); /* Return final code */ } /* * ip_check_options - check that any IP-related options are OK, * and assign appropriate defaults. */ static void ip_check_options(void) { struct hostent *hp; u_int32_t local; ipcp_options *wo = &ipcp_wantoptions[0]; /* * Default our local IP address based on our hostname. * If local IP address already given, don't bother. */ if (wo->ouraddr == 0 && !disable_defaultip) { /* * Look up our hostname (possibly with domain name appended) * and take the first IP address as our local IP address. * If there isn't an IP address for our hostname, too bad. */ wo->accept_local = 1; /* don't insist on this default value */ if ((hp = gethostbyname(hostname)) != NULL) { local = *(u_int32_t *)hp->h_addr; if (local != 0 && !bad_ip_adrs(local)) wo->ouraddr = local; } } ask_for_local = wo->ouraddr != 0 || !disable_defaultip; } /* * ip_demand_conf - configure the interface as though * IPCP were up, for use with dial-on-demand. */ static int ip_demand_conf(int u) { ipcp_options *wo = &ipcp_wantoptions[u]; if (wo->hisaddr == 0 && !noremoteip) { /* make up an arbitrary address for the peer */ wo->hisaddr = htonl(0x0a707070 + ifunit); wo->accept_remote = 1; } if (wo->ouraddr == 0) { /* make up an arbitrary address for us */ wo->ouraddr = htonl(0x0a404040 + ifunit); wo->accept_local = 1; ask_for_local = 0; /* don't tell the peer this address */ } if (!sifaddr(u, wo->ouraddr, wo->hisaddr, GetMask(wo->ouraddr))) return 0; ipcp_script(_PATH_IPPREUP, 1); if (!sifup(u)) return 0; if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE)) return 0; if (wo->default_route) if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr, wo->replace_default_route)) default_route_set[u] = 1; if (wo->proxy_arp) if (sifproxyarp(u, wo->hisaddr)) proxy_arp_set[u] = 1; notice("local IP address %I", wo->ouraddr); if (wo->hisaddr) notice("remote IP address %I", wo->hisaddr); return 1; } /* * ipcp_up - IPCP has come UP. * * Configure the IP network interface appropriately and bring it up. */ static void ipcp_up(fsm *f) { u_int32_t mask; ipcp_options *ho = &ipcp_hisoptions[f->unit]; ipcp_options *go = &ipcp_gotoptions[f->unit]; ipcp_options *wo = &ipcp_wantoptions[f->unit]; int ifindex; IPCPDEBUG(("ipcp: up")); /* * We must have a non-zero IP address for both ends of the link. */ if (!ho->neg_addr && !ho->old_addrs) ho->hisaddr = wo->hisaddr; if (!(go->neg_addr || go->old_addrs) && (wo->neg_addr || wo->old_addrs) && wo->ouraddr != 0) { error("Peer refused to agree to our IP address"); ipcp_close(f->unit, "Refused our IP address"); return; } if (go->ouraddr == 0) { error("Could not determine local IP address"); ipcp_close(f->unit, "Could not determine local IP address"); return; } if (ho->hisaddr == 0 && !noremoteip) { ho->hisaddr = htonl(0x0a404040 + ifunit); warn("Could not determine remote IP address: defaulting to %I", ho->hisaddr); } script_setenv("IPLOCAL", ip_ntoa(go->ouraddr), 0); if (ho->hisaddr != 0) script_setenv("IPREMOTE", ip_ntoa(ho->hisaddr), 1); if (!go->req_dns1) go->dnsaddr[0] = 0; if (!go->req_dns2) go->dnsaddr[1] = 0; if (go->dnsaddr[0]) script_setenv("DNS1", ip_ntoa(go->dnsaddr[0]), 0); if (go->dnsaddr[1]) script_setenv("DNS2", ip_ntoa(go->dnsaddr[1]), 0); if (usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) { script_setenv("USEPEERDNS", "1", 0); create_resolv(go->dnsaddr[0], go->dnsaddr[1]); } /* * Check that the peer is allowed to use the IP address it wants. */ if (ho->hisaddr != 0 && !auth_ip_addr(f->unit, ho->hisaddr)) { error("Peer is not authorized to use remote address %I", ho->hisaddr); ipcp_close(f->unit, "Unauthorized remote IP address"); return; } /* set tcp compression */ sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex); /* * If we are doing dial-on-demand, the interface is already * configured, so we put out any saved-up packets, then set the * interface to pass IP packets. */ if (demand) { if (go->ouraddr != wo->ouraddr || ho->hisaddr != wo->hisaddr) { ipcp_clear_addrs(f->unit, wo->ouraddr, wo->hisaddr, wo->replace_default_route); if (go->ouraddr != wo->ouraddr) { warn("Local IP address changed to %I", go->ouraddr); script_setenv("OLDIPLOCAL", ip_ntoa(wo->ouraddr), 0); wo->ouraddr = go->ouraddr; } else script_unsetenv("OLDIPLOCAL"); if (ho->hisaddr != wo->hisaddr && wo->hisaddr != 0) { warn("Remote IP address changed to %I", ho->hisaddr); script_setenv("OLDIPREMOTE", ip_ntoa(wo->hisaddr), 0); wo->hisaddr = ho->hisaddr; } else script_unsetenv("OLDIPREMOTE"); /* Set the interface to the new addresses */ mask = GetMask(go->ouraddr); if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { if (debug) warn("Interface configuration failed"); ipcp_close(f->unit, "Interface configuration failed"); return; } /* assign a default route through the interface if required */ if (ipcp_wantoptions[f->unit].default_route) if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr, wo->replace_default_route)) default_route_set[f->unit] = 1; /* Make a proxy ARP entry if requested. */ if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp) if (sifproxyarp(f->unit, ho->hisaddr)) proxy_arp_set[f->unit] = 1; } demand_rexmit(PPP_IP); sifnpmode(f->unit, PPP_IP, NPMODE_PASS); } else { /* * Set IP addresses and (if specified) netmask. */ mask = GetMask(go->ouraddr); #if !(defined(SVR4) && (defined(SNI) || defined(__USLC__))) if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { if (debug) warn("Interface configuration failed"); ipcp_close(f->unit, "Interface configuration failed"); return; } #endif ifindex = if_nametoindex(ifname); /* run the pre-up script, if any, and wait for it to finish */ ipcp_script(_PATH_IPPREUP, 1); /* check if preup script renamed the interface */ if (!if_indextoname(ifindex, ifname)) { error("Interface index %d failed to get renamed by a pre-up script", ifindex); ipcp_close(f->unit, "Interface configuration failed"); return; } /* bring the interface up for IP */ if (!sifup(f->unit)) { if (debug) warn("Interface failed to come up"); ipcp_close(f->unit, "Interface configuration failed"); return; } #if (defined(SVR4) && (defined(SNI) || defined(__USLC__))) if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) { if (debug) warn("Interface configuration failed"); ipcp_close(f->unit, "Interface configuration failed"); return; } #endif sifnpmode(f->unit, PPP_IP, NPMODE_PASS); /* assign a default route through the interface if required */ if (ipcp_wantoptions[f->unit].default_route) if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr, wo->replace_default_route)) default_route_set[f->unit] = 1; /* Make a proxy ARP entry if requested. */ if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp) if (sifproxyarp(f->unit, ho->hisaddr)) proxy_arp_set[f->unit] = 1; ipcp_wantoptions[0].ouraddr = go->ouraddr; notice("local IP address %I", go->ouraddr); if (ho->hisaddr != 0) notice("remote IP address %I", ho->hisaddr); if (go->dnsaddr[0]) notice("primary DNS address %I", go->dnsaddr[0]); if (go->dnsaddr[1]) notice("secondary DNS address %I", go->dnsaddr[1]); } reset_link_stats(f->unit); np_up(f->unit, PPP_IP); ipcp_is_up = 1; notify(ip_up_notifier, 0); if (ip_up_hook) ip_up_hook(); /* * Execute the ip-up script, like this: * /etc/ppp/ip-up interface tty speed local-IP remote-IP */ if (ipcp_script_state == s_down && ipcp_script_pid == 0) { ipcp_script_state = s_up; ipcp_script(path_ipup, 0); } } /* * ipcp_down - IPCP has gone DOWN. * * Take the IP network interface down, clear its addresses * and delete routes through it. */ static void ipcp_down(fsm *f) { IPCPDEBUG(("ipcp: down")); /* XXX a bit IPv4-centric here, we only need to get the stats * before the interface is marked down. */ /* XXX more correct: we must get the stats before running the notifiers, * at least for the radius plugin */ update_link_stats(f->unit); notify(ip_down_notifier, 0); 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); print_link_stats(); /* _after_ running the notifiers and ip_down_hook(), * because print_link_stats() sets link_stats_valid * to 0 (zero) */ /* * 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, 0); } /* Execute the ip-down script */ if (ipcp_script_state == s_up && ipcp_script_pid == 0) { ipcp_script_state = s_down; ipcp_script(path_ipdown, 0); } } /* * ipcp_clear_addrs() - clear the interface addresses, routes, * proxy arp entries, etc. */ static void ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, bool replacedefaultroute) { if (proxy_arp_set[unit]) { cifproxyarp(unit, hisaddr); proxy_arp_set[unit] = 0; } /* If replacedefaultroute, sifdefaultroute will be called soon * with replacedefaultroute set and that will overwrite the current * default route. This is the case only when doing demand, otherwise * during demand, this cifdefaultroute would restore the old default * route which is not what we want in this case. In the non-demand * case, we'll delete the default route and restore the old if there * is one saved by an sifdefaultroute with replacedefaultroute. */ if (!replacedefaultroute && 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(fsm *f) { if (ipcp_is_open) { ipcp_is_open = 0; 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(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, 0); } break; case s_down: if (ipcp_fsm[0].state == OPENED) { ipcp_script_state = s_up; ipcp_script(path_ipup, 0); } break; } } /* * ipcp_script - Execute a script with arguments * interface-name tty-name speed local-IP remote-IP. */ static void ipcp_script(char *script, int wait) { 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; if (wait) run_program(script, argv, 0, NULL, NULL, 1); else ipcp_script_pid = run_program(script, argv, 0, ipcp_script_done, NULL, 0); } /* * create_resolv - create the replacement resolv.conf file */ static void create_resolv(u_int32_t peerdns1, u_int32_t 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(u_char *p, int plen, void (*printer) (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: 2), 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 #ifndef IPPROTO_TCP #define IPPROTO_TCP 6 #endif #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(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; }