freebsd-dev/contrib/ipfilter/ipt.c
2002-06-07 08:58:22 +00:00

509 lines
9.6 KiB
C

/*
* Copyright (C) 1993-2002 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#ifdef __FreeBSD__
# ifndef __FreeBSD_cc_version
# include <osreldate.h>
# else
# if __FreeBSD_cc_version < 430000
# include <osreldate.h>
# endif
# endif
#endif
#ifdef __sgi
# define _KMEMUSER
# include <sys/ptimers.h>
#endif
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <sys/types.h>
#if !defined(__SVR4) && !defined(__svr4__) && !defined(__sgi)
#include <strings.h>
#else
#if !defined(__sgi)
#include <sys/byteorder.h>
#endif
#include <sys/file.h>
#endif
#include <sys/param.h>
#include <sys/time.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifndef linux
#include <netinet/ip_var.h>
#endif
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <netinet/tcp.h>
#include <netinet/ip_icmp.h>
#include <net/if.h>
#if __FreeBSD_version >= 300000
# include <net/if_var.h>
#endif
#include <netdb.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <resolv.h>
#include <ctype.h>
#include "ip_compat.h"
#include <netinet/tcpip.h>
#include "ip_fil.h"
#include "ip_nat.h"
#include "ip_state.h"
#include "ip_frag.h"
#include "ipf.h"
#include "ipt.h"
#if !defined(lint)
static const char sccsid[] = "@(#)ipt.c 1.19 6/3/96 (C) 1993-2000 Darren Reed";
static const char rcsid[] = "@(#)$Id: ipt.c,v 2.6.2.22 2002/06/04 14:52:58 darrenr Exp $";
#endif
extern char *optarg;
extern struct frentry *ipfilter[2][2];
extern struct ipread snoop, etherf, tcpd, pcap, iptext, iphex;
extern struct ifnet *get_unit __P((char *, int));
extern void init_ifp __P((void));
extern ipnat_t *natparse __P((char *, int));
extern int fr_running;
int opts = 0;
int rremove = 0;
int use_inet6 = 0;
int main __P((int, char *[]));
int loadrules __P((char *));
int kmemcpy __P((char *, long, int));
void dumpnat __P((void));
void dumpstate __P((void));
char *getifname __P((void *));
void drain_log __P((char *));
int main(argc,argv)
int argc;
char *argv[];
{
char *datain, *iface, *ifname, *packet, *logout;
int fd, i, dir, c, loaded, dump, hlen;
struct ifnet *ifp;
struct ipread *r;
u_long buf[2048];
ip_t *ip;
dir = 0;
dump = 0;
loaded = 0;
r = &iptext;
iface = NULL;
logout = NULL;
ifname = "anon0";
datain = NULL;
nat_init();
fr_stateinit();
initparse();
ipflog_init();
fr_running = 1;
while ((c = getopt(argc, argv, "6bdDEHi:I:l:NoPr:RSTvxX")) != -1)
switch (c)
{
case '6' :
#ifdef USE_INET6
use_inet6 = 1;
break;
#else
fprintf(stderr, "IPv6 not supported\n");
exit(1);
#endif
case 'b' :
opts |= OPT_BRIEF;
break;
case 'd' :
opts |= OPT_DEBUG;
break;
case 'D' :
dump = 1;
break;
case 'i' :
datain = optarg;
break;
case 'I' :
ifname = optarg;
break;
case 'l' :
logout = optarg;
break;
case 'o' :
opts |= OPT_SAVEOUT;
break;
case 'r' :
if (loadrules(optarg) == -1)
return -1;
loaded = 1;
break;
case 'v' :
opts |= OPT_VERBOSE;
break;
case 'E' :
r = &etherf;
break;
case 'H' :
r = &iphex;
break;
case 'N' :
opts |= OPT_NAT;
break;
case 'P' :
r = &pcap;
break;
case 'R' :
rremove = 1;
break;
case 'S' :
r = &snoop;
break;
case 'T' :
r = &tcpd;
break;
case 'x' :
opts |= OPT_HEX;
break;
case 'X' :
r = &iptext;
break;
}
if (loaded == 0) {
(void)fprintf(stderr,"no rules loaded\n");
exit(-1);
}
if (opts & OPT_SAVEOUT)
init_ifp();
if (datain)
fd = (*r->r_open)(datain);
else
fd = (*r->r_open)("-");
if (fd < 0)
exit(-1);
ip = (ip_t *)buf;
while ((i = (*r->r_readip)((char *)buf, sizeof(buf),
&iface, &dir)) > 0) {
if (iface == NULL || *iface == '\0')
iface = ifname;
ifp = get_unit(iface, ip->ip_v);
hlen = 0;
if (!use_inet6) {
ip->ip_off = ntohs(ip->ip_off);
ip->ip_len = ntohs(ip->ip_len);
hlen = ip->ip_hl << 2;
}
#ifdef USE_INET6
else
hlen = sizeof(ip6_t);
#endif
packet = (char *)buf;
/* ipfr_slowtimer(); */
i = fr_check(ip, hlen, ifp, dir, (mb_t **)&packet);
if ((opts & OPT_NAT) == 0)
switch (i)
{
case -5 :
(void)printf("block return-icmp-as-dest");
break;
case -4 :
(void)printf("block return-icmp");
break;
case -3 :
(void)printf("block return-rst");
break;
case -2 :
(void)printf("auth");
break;
case -1 :
(void)printf("block");
break;
case 0 :
(void)printf("pass");
break;
case 1 :
(void)printf("nomatch");
break;
}
if (!use_inet6) {
ip->ip_off = htons(ip->ip_off);
ip->ip_len = htons(ip->ip_len);
}
if (!(opts & OPT_BRIEF)) {
putchar(' ');
printpacket((ip_t *)buf);
printf("--------------");
} else if ((opts & (OPT_BRIEF|OPT_NAT)) == (OPT_NAT|OPT_BRIEF))
printpacket((ip_t *)buf);
#ifndef linux
if (dir && (ifp != NULL) && ip->ip_v && (packet != NULL))
# if defined(__sgi) && (IRIX < 605)
(*ifp->if_output)(ifp, (void *)packet, NULL);
# else
(*ifp->if_output)(ifp, (void *)packet, NULL, 0);
# endif
#endif
if ((opts & (OPT_BRIEF|OPT_NAT)) != (OPT_NAT|OPT_BRIEF))
putchar('\n');
dir = 0;
if (iface != ifname) {
free(iface);
iface = ifname;
}
}
(*r->r_close)();
if (logout != NULL) {
drain_log(logout);
}
if (dump == 1) {
dumpnat();
dumpstate();
}
return 0;
}
/*
* Load in either NAT or ipf rules from a file, which is treated as stdin
* if the name is "-". NOTE, stdin can only be used once as the file is
* closed after use.
*/
int loadrules(file)
char *file;
{
char line[513], *s;
int linenum, i;
void *fr;
FILE *fp;
if (!strcmp(file, "-"))
fp = stdin;
else if (!(fp = fopen(file, "r"))) {
(void)fprintf(stderr, "couldn't open %s\n", file);
return (-1);
}
if (!(opts & OPT_BRIEF))
(void)printf("opening rule file \"%s\"\n", file);
linenum = 0;
while (fgets(line, sizeof(line) - 1, fp)) {
linenum++;
/*
* treat both CR and LF as EOL
*/
if ((s = index(line, '\n')))
*s = '\0';
if ((s = index(line, '\r')))
*s = '\0';
/*
* # is comment marker, everything after is a ignored
*/
if ((s = index(line, '#')))
*s = '\0';
if (!*line)
continue;
/* fake an `ioctl' call :) */
if ((opts & OPT_NAT) != 0) {
if (!(fr = natparse(line, linenum)))
continue;
if (rremove == 0) {
i = IPL_EXTERN(ioctl)(IPL_LOGNAT, SIOCADNAT,
(caddr_t)&fr,
FWRITE|FREAD);
if (opts & OPT_DEBUG)
fprintf(stderr,
"iplioctl(ADNAT,%p,1) = %d\n",
fr, i);
} else {
i = IPL_EXTERN(ioctl)(IPL_LOGNAT, SIOCRMNAT,
(caddr_t)&fr,
FWRITE|FREAD);
if (opts & OPT_DEBUG)
fprintf(stderr,
"iplioctl(RMNAT,%p,1) = %d\n",
fr, i);
}
} else {
if (!(fr = parse(line, linenum)))
continue;
if (rremove == 0) {
i = IPL_EXTERN(ioctl)(0, SIOCADAFR,
(caddr_t)&fr,
FWRITE|FREAD);
if (opts & OPT_DEBUG)
fprintf(stderr,
"iplioctl(ADAFR,%p,1) = %d\n",
fr, i);
} else {
i = IPL_EXTERN(ioctl)(0, SIOCRMAFR,
(caddr_t)&fr,
FWRITE|FREAD);
if (opts & OPT_DEBUG)
fprintf(stderr,
"iplioctl(RMAFR,%p,1) = %d\n",
fr, i);
}
}
}
(void)fclose(fp);
return 0;
}
int kmemcpy(addr, offset, size)
char *addr;
long offset;
int size;
{
bcopy((char *)offset, addr, size);
return 0;
}
/*
* Display the built up NAT table rules and mapping entries.
*/
void dumpnat()
{
ipnat_t *ipn;
nat_t *nat;
printf("List of active MAP/Redirect filters:\n");
for (ipn = nat_list; ipn != NULL; ipn = ipn->in_next)
printnat(ipn, opts & (OPT_DEBUG|OPT_VERBOSE));
printf("\nList of active sessions:\n");
for (nat = nat_instances; nat; nat = nat->nat_next)
printactivenat(nat, opts);
}
/*
* Display the built up state table rules and mapping entries.
*/
void dumpstate()
{
ipstate_t *ips;
printf("List of active state sessions:\n");
for (ips = ips_list; ips != NULL; )
ips = printstate(ips, opts & (OPT_DEBUG|OPT_VERBOSE));
}
/*
* Given a pointer to an interface in the kernel, return a pointer to a
* string which is the interface name.
*/
char *getifname(ptr)
void *ptr;
{
#if defined(NetBSD) && (NetBSD >= 199905) && (NetBSD < 1991011) || \
defined(__OpenBSD__)
#else
char buf[32], *s;
int len;
#endif
struct ifnet netif;
if (ptr == (void *)-1)
return "!";
if (ptr == NULL)
return "-";
if (kmemcpy((char *)&netif, (u_long)ptr, sizeof(netif)) == -1)
return "X";
#if defined(NetBSD) && (NetBSD >= 199905) && (NetBSD < 1991011) || \
defined(__OpenBSD__)
return strdup(netif.if_xname);
#else
if (kmemcpy(buf, (u_long)netif.if_name, sizeof(buf)) == -1)
return "X";
if (netif.if_unit < 10)
len = 2;
else if (netif.if_unit < 1000)
len = 3;
else if (netif.if_unit < 10000)
len = 4;
else
len = 5;
buf[sizeof(buf) - len] = '\0';
for (s = buf; *s && !isdigit(*s); s++)
;
if (isdigit(*s))
*s = '\0';
sprintf(buf + strlen(buf), "%d", netif.if_unit % 10000);
return strdup(buf);
#endif
}
void drain_log(filename)
char *filename;
{
char buffer[IPLLOGSIZE];
struct iovec iov;
struct uio uio;
size_t resid;
int fd;
fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
if (fd == -1) {
perror("drain_log:open");
return;
}
while (1) {
bzero((char *)&iov, sizeof(iov));
iov.iov_base = buffer;
iov.iov_len = sizeof(buffer);
bzero((char *)&uio, sizeof(uio));
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
uio.uio_resid = iov.iov_len;
resid = uio.uio_resid;
if (ipflog_read(0, &uio) == 0) {
/*
* If nothing was read then break out.
*/
if (uio.uio_resid == resid)
break;
write(fd, buffer, resid - uio.uio_resid);
} else
break;
}
close(fd);
}