route.c

早期freebsd实现

/*
 * Copyright (c) 1983, 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
char copyright[] =
"%Z% Copyright (c) 1983 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "%W% (Berkeley) %G%";
#endif /* not lint */

#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/mbuf.h>
#include <sys/kinfo.h>

#include <net/route.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <netns/ns.h>
#include <netiso/iso.h>
#include <netccitt/x25.h>
#include <arpa/inet.h>
#include <netdb.h>

#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <paths.h>

struct keytab {
	char	*kt_cp;
	int	kt_i;
} keywords[] = {
#include "keywords.h"
{0, 0}
};

struct	ortentry route;
union	sockunion {
	struct	sockaddr sa;
	struct	sockaddr_in sin;
	struct	sockaddr_ns sns;
	struct	sockaddr_iso siso;
	struct	sockaddr_dl sdl;
	struct	sockaddr_x25 sx25;
} so_dst, so_gate, so_mask, so_genmask, so_ifa, so_ifp;

union sockunion *so_addrs[] =
	{ &so_dst, &so_gate, &so_mask, &so_genmask, &so_ifp, &so_ifa, 0}; 

typedef union sockunion *sup;
int	pid, rtm_addrs, uid;
int	s;
int	forcehost, forcenet, doflush, nflag, af, qflag, tflag, Cflag, keyword();
int	iflag, verbose, aflen = sizeof (struct sockaddr_in);
int	locking, lockrest, debugonly;
struct	sockaddr_in sin = { sizeof(sin), AF_INET };
struct	rt_metrics rt_metrics;
u_long  rtm_inits;
struct	in_addr inet_makeaddr();
char	*routename(), *netname();
void	flushroutes(), newroute(), monitor();
void	print_getmsg(), print_rtmsg(), pmsg_common(), sodump(), bprintf();
int	getaddr(), rtmsg();
extern	char *inet_ntoa(), *iso_ntoa(), *link_ntoa();

void
usage(cp)
	char *cp;
{
	if (cp)
		(void) fprintf(stderr, "route: botched keyword: %s\n", cp);
	(void) fprintf(stderr,
	    "usage: route [ -Cnqv ] cmd [[ -<qualifers> ] args ]\n");
	exit(1);
	/* NOTREACHED */
}

void
quit(s)
	char *s;
{
	int sverrno = errno;

	(void) fprintf(stderr, "route: ");
	if (s)
		(void) fprintf(stderr, "%s: ", s);
	(void) fprintf(stderr, "%s\n", strerror(sverrno));
	exit(1);
	/* NOTREACHED */
}

#define ROUNDUP(a) \
	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
#define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))

main(argc, argv)
	int argc;
	char **argv;
{
	extern int optind;
	int ch;
	char *argvp;

	if (argc < 2)
		usage((char *)NULL);

	while ((ch = getopt(argc, argv, "Cnqtv")) != EOF)
		switch(ch) {
		case 'C':
			Cflag = 1;	/* Use old ioctls. */
			break;
		case 'n':
			nflag = 1;
			break;
		case 'q':
			qflag = 1;
			break;
		case 'v':
			verbose = 1;
			break;
		case 't':
			tflag = 1;
			break;
		case '?':
		default:
			usage();
		}
	argc -= optind;
	argv += optind;

	pid = getpid();
	uid = getuid();
	if (tflag)
		s = open("/dev/null", O_WRONLY, 0);
	else if (Cflag)
		s = socket(AF_INET, SOCK_RAW, 0);
	else
		s = socket(PF_ROUTE, SOCK_RAW, 0);
	if (s < 0)
		quit("socket");
	if (*argv)
		switch (keyword(*argv)) {
		case K_GET:
			uid = 0;
			/* FALLTHROUGH */

		case K_CHANGE:
			if (Cflag)
				usage("change or get with -C");
			/* FALLTHROUGH */

		case K_ADD:
		case K_DELETE:
			newroute(argc, argv);
			exit(0);
			/* NOTREACHED */

		case K_MONITOR:
			monitor();
			/* NOTREACHED */

		case K_FLUSH:
			flushroutes(argc, argv);
			exit(0);
			/* NOTREACHED */
		}
	usage(*argv);
	/* NOTREACHED */
}

/*
 * Purge all entries in the routing tables not
 * associated with network interfaces.
 */
void
flushroutes(argc, argv)
	int argc;
	char *argv[];
{
	int needed, seqno, rlen;
	char *buf, *next, *lim;
	register struct rt_msghdr *rtm;

	if (uid)
		quit("must be root to alter routing table");
	shutdown(s, 0); /* Don't want to read back our messages */
	if (argc > 1) {
		argv++;
		if (argc == 2 && **argv == '-')
		    switch (keyword(*argv + 1)) {
			case K_INET:
				af = AF_INET;
				break;
			case K_XNS:
				af = AF_NS;
				break;
			case K_LINK:
				af = AF_LINK;
				break;
			case K_ISO:
			case K_OSI:
				af = AF_ISO;
				break;
			case K_X25:
				af = AF_CCITT;
			default:
				goto bad;
		} else
bad:			usage(*argv);
	}
	if ((needed = getkerninfo(KINFO_RT_DUMP, 0, 0, 0)) < 0)
		quit("route-getkerninfo-estimate");
	if ((buf = malloc(needed)) == NULL)
		quit("malloc");
	if ((rlen = getkerninfo(KINFO_RT_DUMP, buf, &needed, 0)) < 0)
		quit("actual retrieval of routing table");
	lim = buf + rlen;
	seqno = 0;		/* ??? */
	for (next = buf; next < lim; next += rtm->rtm_msglen) {
		rtm = (struct rt_msghdr *)next;
		if ((rtm->rtm_flags & RTF_GATEWAY) == 0)
			continue;
		if (af) {
			struct sockaddr *sa = (struct sockaddr *)(rtm + 1);

			if (sa->sa_family != af)
				continue;
		}
		rtm->rtm_type = RTM_DELETE;
		rtm->rtm_seq = seqno;
		rlen = write(s, next, rtm->rtm_msglen);
		if (rlen < (int)rtm->rtm_msglen) {
			(void) fprintf(stderr,
			    "route: write to routing socket: %s\n",
			    strerror(errno));
			(void) printf("got only %d for rlen\n", rlen);
			break;
		}
		seqno++;
		if (qflag)
			continue;
		if (verbose)
			print_rtmsg(rtm, rlen);
		else {
			struct sockaddr *sa = (struct sockaddr *)(rtm + 1);
			(void) printf("%-20.20s ", rtm->rtm_flags & RTF_HOST ?
			    routename(sa) : netname(sa));
			sa = (struct sockaddr *)(sa->sa_len + (char *)sa);
			(void) printf("%-20.20s ", routename(sa));
			(void) printf("done\n");
		}
	}
}
	
char *
routename(sa)
	struct sockaddr *sa;
{
	register char *cp;
	static char line[50];
	struct hostent *hp;
	static char domain[MAXHOSTNAMELEN + 1];
	static int first = 1;
	char *ns_print();

	if (first) {
		first = 0;
		if (gethostname(domain, MAXHOSTNAMELEN) == 0 &&
		    (cp = index(domain, '.')))
			(void) strcpy(domain, cp + 1);
		else
			domain[0] = 0;
	}
	switch (sa->sa_family) {

	case AF_INET:
	    {	struct in_addr in;
		in = ((struct sockaddr_in *)sa)->sin_addr;

		cp = 0;
		if (in.s_addr == INADDR_ANY)
			cp = "default";
		if (cp == 0 && !nflag) {
			hp = gethostbyaddr((char *)&in, sizeof (struct in_addr),
				AF_INET);
			if (hp) {
				if ((cp = index(hp->h_name, '.')) &&
				    !strcmp(cp + 1, domain))
					*cp = 0;
				cp = hp->h_name;
			}
		}
		if (cp)
			strcpy(line, cp);
		else {
#define C(x)	((x) & 0xff)
			in.s_addr = ntohl(in.s_addr);
			(void) sprintf(line, "%u.%u.%u.%u", C(in.s_addr >> 24),
			   C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
		}
		break;
	    }

	case AF_NS:
		return (ns_print((struct sockaddr_ns *)sa));

	case AF_LINK:
		return (link_ntoa((struct sockaddr_dl *)sa));

	case AF_ISO:
		(void) sprintf(line, "iso %s",
		    iso_ntoa(&((struct sockaddr_iso *)sa)->siso_addr));
		break;

	default:
	    {	u_short *s = (u_short *)sa->sa_data;
		u_short *slim = s + ((sa->sa_len + 1) >> 1);
		char *cp = line + sprintf(line, "(%d)", sa->sa_family);

		while (s < slim)
			cp += sprintf(cp, " %x", *s++);
		break;
	    }
	}
	return (line);
}

/*
 * Return the name of the network whose address is given.
 * The address is assumed to be that of a net or subnet, not a host.
 */
char *
netname(sa)
	struct sockaddr *sa;
{
	char *cp = 0;
	static char line[50];
	struct netent *np = 0;
	u_long net, mask;
	register u_long i;
	int subnetshift;
	char *ns_print();

	switch (sa->sa_family) {

	case AF_INET:
	    {	struct in_addr in;
		in = ((struct sockaddr_in *)sa)->sin_addr;

		i = in.s_addr = ntohl(in.s_addr);
		if (in.s_addr == 0)
			cp = "default";
		else if (!nflag) {
			if (IN_CLASSA(i)) {
				mask = IN_CLASSA_NET;
				subnetshift = 8;
			} else if (IN_CLASSB(i)) {
				mask = IN_CLASSB_NET;
				subnetshift = 8;
			} else {
				mask = IN_CLASSC_NET;
				subnetshift = 4;
			}
			/*
			 * If there are more bits than the standard mask
			 * would suggest, subnets must be in use.
			 * Guess at the subnet mask, assuming reasonable
			 * width subnet fields.
			 */
			while (in.s_addr &~ mask)
				mask = (long)mask >> subnetshift;
			net = in.s_addr & mask;
			while ((mask & 1) == 0)
				mask >>= 1, net >>= 1;
			np = getnetbyaddr(net, AF_INET);
			if (np)
				cp = np->n_name;
		}
		if (cp)
			strcpy(line, cp);
		else if ((in.s_addr & 0xffffff) == 0)
			(void) sprintf(line, "%u", C(in.s_addr >> 24));
		else if ((in.s_addr & 0xffff) == 0)
			(void) sprintf(line, "%u.%u", C(in.s_addr >> 24),
			    C(in.s_addr >> 16));
		else if ((in.s_addr & 0xff) == 0)
			(void) sprintf(line, "%u.%u.%u", C(in.s_addr >> 24),
			    C(in.s_addr >> 16), C(in.s_addr >> 8));
		else
			(void) sprintf(line, "%u.%u.%u.%u", C(in.s_addr >> 24),
			    C(in.s_addr >> 16), C(in.s_addr >> 8),
			    C(in.s_addr));
		break;
	    }

	case AF_NS:
		return (ns_print((struct sockaddr_ns *)sa));
		break;

	case AF_LINK:
		return (link_ntoa((struct sockaddr_dl *)sa));

	case AF_ISO:
		(void) sprintf(line, "iso %s",
		    iso_ntoa(&((struct sockaddr_iso *)sa)->siso_addr));
		break;

	default:
	    {	u_short *s = (u_short *)sa->sa_data;
		u_short *slim = s + ((sa->sa_len + 1)>>1);
		char *cp = line + sprintf(line, "af %d:", sa->sa_family);

		while (s < slim)
			cp += sprintf(cp, " %x", *s++);
		break;
	    }
	}
	return (line);
}

void
set_metric(value, key)
	char *value;
	int key;
{
	int flag = 0; 
	u_long noval, *valp = &noval;

	switch (key) {
#define caseof(x, y, z)	case x: valp = &rt_metrics.z; flag = y; break
	caseof(K_MTU, RTV_MTU, rmx_mtu);
	caseof(K_HOPCOUNT, RTV_HOPCOUNT, rmx_hopcount);
	caseof(K_EXPIRE, RTV_EXPIRE, rmx_expire);
	caseof(K_RECVPIPE, RTV_RPIPE, rmx_recvpipe);
	caseof(K_SENDPIPE, RTV_SPIPE, rmx_sendpipe);
	caseof(K_SSTHRESH, RTV_SSTHRESH, rmx_ssthresh);
	caseof(K_RTT, RTV_RTT, rmx_rtt);
	caseof(K_RTTVAR, RTV_RTTVAR, rmx_rttvar);
	}
	rtm_inits |= flag;
	if (lockrest || locking)
		rt_metrics.rmx_locks |= flag;
	if (locking)
		locking = 0;
	*valp = atoi(value);
}

void
newroute(argc, argv)
	int argc;
	register char **argv;
{
	char *cmd, *dest = "", *gateway = "", *err;
	int ishost = 0, ret, attempts, oerrno, flags = 0;
	int key;
	struct hostent *hp = 0;

	if (uid)
		quit("must be root to alter routing table");
	cmd = argv[0];
	if (*cmd != 'g')
		shutdown(s, 0); /* Don't want to read back our messages */
	while (--argc > 0) {
		if (**(++argv)== '-') {
			switch (key = keyword(1 + *argv)) {
			case K_LINK:
				af = AF_LINK;
				aflen = sizeof(struct sockaddr_dl);
				break;
			case K_OSI:
			case K_ISO:
				af = AF_ISO;
				aflen = sizeof(struct sockaddr_iso);
				break;
			case K_INET:
				af = AF_INET;
				aflen = sizeof(struct sockaddr_in);
				break;
			case K_X25:
				af = AF_CCITT;
				aflen = sizeof(struct sockaddr_x25);
				break;
			case K_SA:
				af = 0;
				aflen = sizeof(union sockunion);
				break;
			case K_XNS:
				af = AF_NS;
				aflen = sizeof(struct sockaddr_ns);
				break;
			case K_IFACE:
			case K_INTERFACE:
				iflag++;
				break;
			case K_LOCK:
				locking = 1;
				break;
			case K_LOCKREST:
				lockrest = 1;
				break;
			case K_HOST:
				forcehost++;
				break;
			case K_REJECT:
				flags |= RTF_REJECT;
				break;
			case K_PROTO1:
				flags |= RTF_PROTO1;
				break;
			case K_PROTO2:
				flags |= RTF_PROTO2;
				break;
			case K_CLONING:
				flags |= RTF_CLONING;
				break;
			case K_XRESOLVE:
				flags |= RTF_XRESOLVE;
				break;
			case K_IFA:
				argc--;
				(void) getaddr(RTA_IFA, *++argv, 0);
				break;
			case K_IFP:
				argc--;
				(void) getaddr(RTA_IFP, *++argv, 0);
				break;
			case K_GENMASK:
				argc--;
				(void) getaddr(RTA_GENMASK, *++argv, 0);
				break;
			case K_GATEWAY:
				argc--;
				(void) getaddr(RTA_GATEWAY, *++argv, 0);
				break;
			case K_DST:
				argc--;
				ishost = getaddr(RTA_DST, *++argv, &hp);
				dest = *argv;
				break;
			case K_NETMASK:
				argc--;
				(void) getaddr(RTA_NETMASK, *++argv, 0);
				/* FALLTHROUGH */
			case K_NET:
				forcenet++;
				break;
			case K_MTU:
			case K_HOPCOUNT:
			case K_EXPIRE:
			case K_RECVPIPE:
			case K_SENDPIPE:
			case K_SSTHRESH:
			case K_RTT:
			case K_RTTVAR:
				argc--;
				set_metric(*++argv, key);
				break;
			default:
				usage(1+*argv);
			}
		} else {
			if ((rtm_addrs & RTA_DST) == 0) {
				dest = *argv;
				ishost = getaddr(RTA_DST, *argv, &hp);
			} else if ((rtm_addrs & RTA_GATEWAY) == 0) {
				gateway = *argv;
				(void) getaddr(RTA_GATEWAY, *argv, &hp);
			} else {
				int ret = atoi(*argv);
				if (ret == 0) {
				    printf("%s,%s", "old usage of trailing 0",
					   "assuming route to if\n");
				    iflag = 1;
				    continue;
				} else if (ret > 0 && ret < 10) {
				    printf("old usage of trailing digit, ");
				    printf("assuming route via gateway\n");
				    iflag = 0;
				    continue;
				}
				(void) getaddr(RTA_NETMASK, *argv, 0);
			}
		}