/* * multilink.c - support routines for multilink. * * Copyright (c) 2000-2002 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to *    endorse or promote products derived from this software without *    prior written permission. * * 3. Redistributions of any form whatsoever must retain the following *    acknowledgment: *    "This product includes software developed by Paul Mackerras *     <paulus@samba.org>". * * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL THE AUTHORS 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 <string.h>#include <ctype.h>#include <stdlib.h>#include <netdb.h>#include <errno.h>#include <signal.h>#include <netinet/in.h>#include <unistd.h>#include "pppd.h"#include "fsm.h"#include "lcp.h"#include "tdb.h"bool endpoint_specified;	/* user gave explicit endpoint discriminator */char *bundle_id;		/* identifier for our bundle */char *blinks_id;		/* key for the list of links */bool doing_multilink;		/* multilink was enabled and agreed to */bool multilink_master;		/* we own the multilink bundle */extern TDB_CONTEXT *pppdb;extern char db_key[];static void make_bundle_links __P((int append));static void remove_bundle_link __P((void));static void iterate_bundle_links __P((void (*func) __P((char *))));static int get_default_epdisc __P((struct epdisc *));static int parse_num __P((char *str, const char *key, int *valp));static int owns_unit __P((TDB_DATA pid, int unit));#define set_ip_epdisc(ep, addr) do {	\	ep->length = 4;			\	ep->value[0] = addr >> 24;	\	ep->value[1] = addr >> 16;	\	ep->value[2] = addr >> 8;	\	ep->value[3] = addr;		\} while (0)#define LOCAL_IP_ADDR(addr)						  \	(((addr) & 0xff000000) == 0x0a000000		/* 10.x.x.x */	  \	 || ((addr) & 0xfff00000) == 0xac100000		/* 172.16.x.x */  \	 || ((addr) & 0xffff0000) == 0xc0a80000)	/* 192.168.x.x */#define process_exists(n)	(kill((n), 0) == 0 || errno != ESRCH)voidmp_check_options(){	lcp_options *wo = &lcp_wantoptions[0];	lcp_options *ao = &lcp_allowoptions[0];	doing_multilink = 0;	if (!multilink)		return;	/* if we're doing multilink, we have to negotiate MRRU */	if (!wo->neg_mrru) {		/* mrru not specified, default to mru */		wo->mrru = wo->mru;		wo->neg_mrru = 1;	}	ao->mrru = ao->mru;	ao->neg_mrru = 1;	if (!wo->neg_endpoint && !noendpoint) {		/* get a default endpoint value */		wo->neg_endpoint = get_default_epdisc(&wo->endpoint);	}}/* * Make a new bundle or join us to an existing bundle * if we are doing multilink. */intmp_join_bundle(){	lcp_options *go = &lcp_gotoptions[0];	lcp_options *ho = &lcp_hisoptions[0];	lcp_options *ao = &lcp_allowoptions[0];	int unit, pppd_pid;	int l, mtu;	char *p;	TDB_DATA key, pid, rec;	if (doing_multilink) {		/* have previously joined a bundle */		if (!go->neg_mrru || !ho->neg_mrru) {			notice("oops, didn't get multilink on renegotiation");			lcp_close(0, "multilink required");			return 0;		}		/* XXX should check the peer_authname and ho->endpoint		   are the same as previously */		return 0;	}	if (!go->neg_mrru || !ho->neg_mrru) {		/* not doing multilink */		if (go->neg_mrru)			notice("oops, multilink negotiated only for receive");		mtu = ho->neg_mru? ho->mru: PPP_MRU;		if (mtu > ao->mru)			mtu = ao->mru;		if (demand) {			/* already have a bundle */			cfg_bundle(0, 0, 0, 0);			netif_set_mtu(0, mtu);			return 0;		}		make_new_bundle(0, 0, 0, 0);		set_ifunit(1);		netif_set_mtu(0, mtu);		return 0;	}	doing_multilink = 1;	/*	 * Find the appropriate bundle or join a new one.	 * First we make up a name for the bundle.	 * The length estimate is worst-case assuming every	 * character has to be quoted.	 */	l = 4 * strlen(peer_authname) + 10;	if (ho->neg_endpoint)		l += 3 * ho->endpoint.length + 8;	if (bundle_name)		l += 3 * strlen(bundle_name) + 2;	bundle_id = malloc(l);	if (bundle_id == 0)		novm("bundle identifier");	p = bundle_id;	p += slprintf(p, l-1, "BUNDLE=\"%q\"", peer_authname);	if (ho->neg_endpoint || bundle_name)		*p++ = '/';	if (ho->neg_endpoint)		p += slprintf(p, bundle_id+l-p, "%s",			      epdisc_to_str(&ho->endpoint));	if (bundle_name)		p += slprintf(p, bundle_id+l-p, "/%v", bundle_name);	/* Make the key for the list of links belonging to the bundle */	l = p - bundle_id;	blinks_id = malloc(l + 7);	if (blinks_id == NULL)		novm("bundle links key");	slprintf(blinks_id, l + 7, "BUNDLE_LINKS=%s", bundle_id + 7);	/*	 * For demand mode, we only need to configure the bundle	 * and attach the link.	 */	mtu = MIN(ho->mrru, ao->mru);	if (demand) {		cfg_bundle(go->mrru, ho->mrru, go->neg_ssnhf, ho->neg_ssnhf);		netif_set_mtu(0, mtu);		script_setenv("BUNDLE", bundle_id + 7, 1);		return 0;	}	/*	 * Check if the bundle ID is already in the database.	 */	unit = -1;	lock_db();	key.dptr = bundle_id;	key.dsize = p - bundle_id;	pid = tdb_fetch(pppdb, key);	if (pid.dptr != NULL) {		/* bundle ID exists, see if the pppd record exists */		rec = tdb_fetch(pppdb, pid);		if (rec.dptr != NULL && rec.dsize > 0) {			/* make sure the string is null-terminated */			rec.dptr[rec.dsize-1] = 0;			/* parse the interface number */			parse_num(rec.dptr, "IFNAME=ppp", &unit);			/* check the pid value */			if (!parse_num(rec.dptr, "PPPD_PID=", &pppd_pid)			    || !process_exists(pppd_pid)			    || !owns_unit(pid, unit))				unit = -1;			free(rec.dptr);		}		free(pid.dptr);	}	if (unit >= 0) {		/* attach to existing unit */		if (bundle_attach(unit)) {			set_ifunit(0);			script_setenv("BUNDLE", bundle_id + 7, 0);			make_bundle_links(1);			unlock_db();			info("Link attached to %s", ifname);			return 1;		}		/* attach failed because bundle doesn't exist */	}	/* we have to make a new bundle */	make_new_bundle(go->mrru, ho->mrru, go->neg_ssnhf, ho->neg_ssnhf);	set_ifunit(1);	netif_set_mtu(0, mtu);	script_setenv("BUNDLE", bundle_id + 7, 1);	make_bundle_links(0);	unlock_db();	info("New bundle %s created", ifname);	multilink_master = 1;	return 0;}void mp_exit_bundle(){	lock_db();	remove_bundle_link();	unlock_db();}static void sendhup(char *str){	int pid;	if (parse_num(str, "PPPD_PID=", &pid) && pid != getpid()) {		if (debug)			dbglog("sending SIGHUP to process %d", pid);		kill(pid, SIGHUP);	}}void mp_bundle_terminated(){	TDB_DATA key;	bundle_terminating = 1;	upper_layers_down(0);	notice("Connection terminated.");	print_link_stats();	if (!demand) {		remove_pidfiles();		script_unsetenv("IFNAME");	}	lock_db();	destroy_bundle();	iterate_bundle_links(sendhup);	key.dptr = blinks_id;	key.dsize = strlen(blinks_id);	tdb_delete(pppdb, key);	unlock_db();	new_phase(PHASE_DEAD);}static void make_bundle_links(int append){	TDB_DATA key, rec;	char *p;	char entry[32];	int l;	key.dptr = blinks_id;	key.dsize = strlen(blinks_id);	slprintf(entry, sizeof(entry), "%s;", db_key);	p = entry;	if (append) {		rec = tdb_fetch(pppdb, key);		if (rec.dptr != NULL && rec.dsize > 0) {			rec.dptr[rec.dsize-1] = 0;			if (strstr(rec.dptr, db_key) != NULL) {				/* already in there? strange */				warn("link entry already exists in tdb");				return;			}			l = rec.dsize + strlen(entry);			p = malloc(l);			if (p == NULL)				novm("bundle link list");			slprintf(p, l, "%s%s", rec.dptr, entry);		} else {			warn("bundle link list not found");		}		if (rec.dptr != NULL)			free(rec.dptr);	}	rec.dptr = p;	rec.dsize = strlen(p) + 1;	if (tdb_store(pppdb, key, rec, TDB_REPLACE))		error("couldn't %s bundle link list",		      append? "update": "create");	if (p != entry)		free(p);}static void remove_bundle_link(){	TDB_DATA key, rec;	char entry[32];	char *p, *q;	int l;	key.dptr = blinks_id;	key.dsize = strlen(blinks_id);	slprintf(entry, sizeof(entry), "%s;", db_key);	rec = tdb_fetch(pppdb, key);	if (rec.dptr == NULL || rec.dsize <= 0) {		if (rec.dptr != NULL)			free(rec.dptr);		return;	}	rec.dptr[rec.dsize-1] = 0;	p = strstr(rec.dptr, entry);	if (p != NULL) {		q = p + strlen(entry);		l = strlen(q) + 1;		memmove(p, q, l);		rec.dsize = p - rec.dptr + l;		if (tdb_store(pppdb, key, rec, TDB_REPLACE))			error("couldn't update bundle link list (removal)");	}	free(rec.dptr);}static void iterate_bundle_links(void (*func)(char *)){	TDB_DATA key, rec, pp;	char *p, *q;	key.dptr = blinks_id;	key.dsize = strlen(blinks_id);	rec = tdb_fetch(pppdb, key);	if (rec.dptr == NULL || rec.dsize <= 0) {		error("bundle link list not found (iterating list)");		if (rec.dptr != NULL)			free(rec.dptr);		return;	}	p = rec.dptr;	p[rec.dsize-1] = 0;	while ((q = strchr(p, ';')) != NULL) {		*q = 0;		key.dptr = p;		key.dsize = q - p;		pp = tdb_fetch(pppdb, key);		if (pp.dptr != NULL && pp.dsize > 0) {			pp.dptr[pp.dsize-1] = 0;			func(pp.dptr);		}		if (pp.dptr != NULL)			free(pp.dptr);		p = q + 1;	}	free(rec.dptr);}static intparse_num(str, key, valp)     char *str;     const char *key;     int *valp;{	char *p, *endp;	int i;	p = strstr(str, key);	if (p != 0) {		p += strlen(key);		i = strtol(p, &endp, 10);		if (endp != p && (*endp == 0 || *endp == ';')) {			*valp = i;			return 1;		}	}	return 0;}/* * Check whether the pppd identified by `key' still owns ppp unit `unit'. */static intowns_unit(key, unit)     TDB_DATA key;     int unit;{	char ifkey[32];	TDB_DATA kd, vd;	int ret = 0;	slprintf(ifkey, sizeof(ifkey), "IFNAME=ppp%d", unit);	kd.dptr = ifkey;	kd.dsize = strlen(ifkey);	vd = tdb_fetch(pppdb, kd);	if (vd.dptr != NULL) {		ret = vd.dsize == key.dsize			&& memcmp(vd.dptr, key.dptr, vd.dsize) == 0;		free(vd.dptr);	}	return ret;}static intget_default_epdisc(ep)     struct epdisc *ep;{	char *p;	struct hostent *hp;	u_int32_t addr;	/* First try for an ethernet MAC address */	p = get_first_ethernet();	if (p != 0 && get_if_hwaddr(ep->value, p) >= 0) {		ep->class = EPD_MAC;		ep->length = 6;		return 1;	}	/* see if our hostname corresponds to a reasonable IP address */	hp = gethostbyname(hostname);	if (hp != NULL) {		addr = *(u_int32_t *)hp->h_addr;		if (!bad_ip_adrs(addr)) {			addr = ntohl(addr);			if (!LOCAL_IP_ADDR(addr)) {				ep->class = EPD_IP;				set_ip_epdisc(ep, addr);				return 1;			}		}	}	return 0;}/* * epdisc_to_str - make a printable string from an endpoint discriminator. */static char *endp_class_names[] = {    "null", "local", "IP", "MAC", "magic", "phone"};char *epdisc_to_str(ep)     struct epdisc *ep;{	static char str[MAX_ENDP_LEN*3+8];	u_char *p = ep->value;	int i, mask = 0;	char *q, c, c2;	if (ep->class == EPD_NULL && ep->length == 0)		return "null";	if (ep->class == EPD_IP && ep->length == 4) {		u_int32_t addr;		GETLONG(addr, p);		slprintf(str, sizeof(str), "IP:%I", htonl(addr));		return str;	}	c = ':';	c2 = '.';	if (ep->class == EPD_MAC && ep->length == 6)		c2 = ':';	else if (ep->class == EPD_MAGIC && (ep->length % 4) == 0)		mask = 3;	q = str;	if (ep->class <= EPD_PHONENUM)		q += slprintf(q, sizeof(str)-1, "%s",			      endp_class_names[ep->class]);	else		q += slprintf(q, sizeof(str)-1, "%d", ep->class);	c = ':';	for (i = 0; i < ep->length && i < MAX_ENDP_LEN; ++i) {		if ((i & mask) == 0) {			*q++ = c;			c = c2;		}		q += slprintf(q, str + sizeof(str) - q, "%.2x", ep->value[i]);	}	return str;}static int hexc_val(int c){	if (c >= 'a')		return c - 'a' + 10;	if (c >= 'A')		return c - 'A' + 10;	return c - '0';}intstr_to_epdisc(ep, str)     struct epdisc *ep;     char *str;{	int i, l;	char *p, *endp;	for (i = EPD_NULL; i <= EPD_PHONENUM; ++i) {		int sl = strlen(endp_class_names[i]);		if (strncasecmp(str, endp_class_names[i], sl) == 0) {			str += sl;			break;		}	}	if (i > EPD_PHONENUM) {		/* not a class name, try a decimal class number */		i = strtol(str, &endp, 10);		if (endp == str)			return 0;	/* can't parse class number */		str = endp;	}	ep->class = i;	if (*str == 0) {		ep->length = 0;		return 1;	}	if (*str != ':' && *str != '.')		return 0;	++str;	if (i == EPD_IP) {		u_int32_t addr;		i = parse_dotted_ip(str, &addr);		if (i == 0 || str[i] != 0)			return 0;		set_ip_epdisc(ep, addr);		return 1;	}	if (i == EPD_MAC && get_if_hwaddr(ep->value, str) >= 0) {		ep->length = 6;		return 1;	}	p = str;	for (l = 0; l < MAX_ENDP_LEN; ++l) {		if (*str == 0)			break;		if (p <= str)			for (p = str; isxdigit(*p); ++p)				;		i = p - str;		if (i == 0)			return 0;		ep->value[l] = hexc_val(*str++);		if ((i & 1) == 0)			ep->value[l] = (ep->value[l] << 4) + hexc_val(*str++);		if (*str == ':' || *str == '.')			++str;	}	if (*str != 0 || (ep->class == EPD_MAC && l != 6))		return 0;	ep->length = l;	return 1;}