freebsd-skq/contrib/ipfilter/ipmon.c
1997-02-09 22:50:16 +00:00

583 lines
12 KiB
C

/*
* (C)opyright 1993-1996 by Darren Reed.
*
* Redistribution and use in source and binary forms are permitted
* provided that this notice is preserved and due credit is given
* to the original author and the contributors.
*/
#include <stdio.h>
#include <assert.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <syslog.h>
#include <sys/errno.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/uio.h>
#if !defined(__SVR4) && !defined(__svr4__)
#include <sys/dir.h>
#include <sys/mbuf.h>
#else
#include <sys/byteorder.h>
#endif
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/user.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <netinet/ip_icmp.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <ctype.h>
#if !defined(lint) && defined(LIBC_SCCS)
static char rcsid[] = "$Id: ipmon.c,v 2.0.1.2 1997/02/04 14:49:19 darrenr Exp $";
#endif
#include "ip_fil.h"
struct flags {
int value;
char flag;
};
struct flags tcpfl[] = {
{ TH_ACK, 'A' },
{ TH_RST, 'R' },
{ TH_SYN, 'S' },
{ TH_FIN, 'F' },
{ TH_URG, 'U' },
{ TH_PUSH,'P' },
{ 0, '\0' }
};
static char line[2048];
static void printpacket(), dumphex();
static int opts = 0;
#define OPT_SYSLOG 0x01
#define OPT_RESOLVE 0x02
#define OPT_HEXBODY 0x04
#define OPT_VERBOSE 0x08
#define OPT_HEXHDR 0x10
#ifndef LOGFAC
#define LOGFAC LOG_LOCAL0
#endif
void printiplci(icp)
struct ipl_ci *icp;
{
printf("sec %ld usec %ld hlen %d plen %d\n", icp->sec, icp->usec,
icp->hlen, icp->plen);
}
void resynclog(fd, iplcp, log)
int fd;
struct ipl_ci *iplcp;
FILE *log;
{
time_t now;
char *s = NULL;
int len, nr = 0;
do {
if (s) {
s = (char *)&iplcp->sec;
if (opts & OPT_SYSLOG) {
syslog(LOG_INFO, "Sync bytes:");
syslog(LOG_INFO, " %02x %02x %02x %02x",
*s, *(s+1), *(s+2), *(s+3));
syslog(LOG_INFO, " %02x %02x %02x %02x\n",
*(s+4), *(s+5), *(s+6), *(s+7));
} else {
fprintf(log, "Sync bytes:");
fprintf(log, " %02x %02x %02x %02x",
*s, *(s+1), *(s+2), *(s+3));
fprintf(log, " %02x %02x %02x %02x\n",
*(s+4), *(s+5), *(s+6), *(s+7));
}
}
do {
s = (char *)&iplcp->sec;
len = sizeof(iplcp->sec);
while (len) {
switch ((nr = read(fd, s, len)))
{
case -1:
case 0:
return;
default :
s += nr;
len -= nr;
now = time(NULL);
break;
}
}
} while ((now < iplcp->sec) ||
((iplcp->sec - now) > (86400*5)));
len = sizeof(iplcp->usec);
while (len) {
switch ((nr = read(fd, s, len)))
{
case -1:
case 0:
return;
default :
s += nr;
len -= nr;
break;
}
}
} while (iplcp->usec > 1000000);
len = sizeof(*iplcp) - sizeof(iplcp->sec) - sizeof(iplcp->usec);
while (len) {
switch ((nr = read(fd, s, len)))
{
case -1:
case 0:
return;
default :
s += nr;
len -= nr;
break;
}
}
}
int readlogentry(fd, lenp, buf, bufsize, log)
int fd, bufsize, *lenp;
char *buf;
FILE *log;
{
struct ipl_ci *icp = (struct ipl_ci *)buf;
time_t now;
char *s;
int len, n = bufsize, tr = sizeof(struct ipl_ci), nr;
if (bufsize < tr)
return 1;
for (s = buf; (n > 0) && (tr > 0); s += nr, n -= nr) {
nr = read(fd, s, tr);
if (nr > 0)
tr -= nr;
else
return -1;
}
now = time(NULL);
if ((icp->hlen > 92) || (now < icp->sec) ||
((now - icp->sec) > (86400*5))) {
if (opts & OPT_SYSLOG)
syslog(LOG_INFO, "Out of sync! (1,%x)\n", now);
else
fprintf(log, "Out of sync! (1,%x)\n", now);
dumphex(log, buf, sizeof(struct ipl_ci));
resynclog(fd, icp, log);
}
len = (int)((u_int)icp->plen);
if (len > 128 || len < 0) {
if (opts & OPT_SYSLOG)
syslog(LOG_INFO, "Out of sync! (2,%d)\n", len);
else
fprintf(log, "Out of sync! (2,%d)\n", len);
dumphex(log, buf, sizeof(struct ipl_ci));
resynclog(fd, icp, log);
}
tr = icp->hlen + icp->plen;
if (n < tr)
return 1;
for (; (n > 0) && (tr > 0); s += nr, n-= nr) {
nr = read(fd, s, tr);
if (nr > 0)
tr -= nr;
else
return -1;
}
*lenp = s - buf;
return 0;
}
char *hostname(res, ip)
int res;
struct in_addr ip;
{
struct hostent *hp;
if (!res)
return inet_ntoa(ip);
hp = gethostbyaddr((char *)&ip, sizeof(ip), AF_INET);
if (!hp)
return inet_ntoa(ip);
return hp->h_name;
}
char *portname(res, proto, port)
int res;
char *proto;
u_short port;
{
static char pname[8];
struct servent *serv;
(void) sprintf(pname, "%hu", htons(port));
if (!res)
return pname;
serv = getservbyport((int)port, proto);
if (!serv)
return pname;
return serv->s_name;
}
static void dumphex(log, buf, len)
FILE *log;
u_char *buf;
int len;
{
char line[80];
int i, j, k;
u_char *s = buf, *t = (u_char *)line;
for (i = len, j = 0; i; i--, j++, s++) {
if (j && !(j & 0xf)) {
*t++ = '\n';
*t = '\0';
fputs(line, stdout);
t = (u_char *)line;
*t = '\0';
}
sprintf(t, "%02x", *s & 0xff);
t += 2;
if (!((j + 1) & 0xf)) {
s -= 15;
sprintf(t, " ");
t += 8;
for (k = 16; k; k--, s++)
*t++ = (isprint(*s) ? *s : '.');
s--;
}
if ((j + 1) & 0xf)
*t++ = ' ';;
}
if (j & 0xf) {
for (k = 16 - (j & 0xf); k; k--) {
*t++ = ' ';
*t++ = ' ';
*t++ = ' ';
}
sprintf(t, " ");
t += 7;
s -= j & 0xf;
for (k = j & 0xf; k; k--, s++)
*t++ = (isprint(*s) ? *s : '.');
*t++ = '\n';
*t = '\0';
}
fputs(line, stdout);
fflush(stdout);
}
static void printpacket(log, buf, blen)
FILE *log;
char *buf;
int blen;
{
struct protoent *pr;
struct tcphdr *tp;
struct icmp *ic;
struct ip *ipc;
struct tm *tm;
char c[3], pname[8], *t, *proto;
u_short hl, p;
int i, lvl, res;
#if !SOLARIS && !(defined(NetBSD) && (NetBSD <= 1991011) && (NetBSD >= 199603))
int len;
#endif
struct ip *ip;
struct ipl_ci *lp;
lp = (struct ipl_ci *)buf;
ip = (struct ip *)(buf + sizeof(*lp));
res = (opts & OPT_RESOLVE) ? 1 : 0;
t = line;
*t = '\0';
hl = (ip->ip_hl << 2);
p = (u_short)ip->ip_p;
tm = localtime((time_t *)&lp->sec);
if (!(opts & OPT_SYSLOG)) {
(void) sprintf(t, "%2d/%02d/%4d ",
tm->tm_mday, tm->tm_mon + 1, tm->tm_year + 1900);
t += strlen(t);
}
#if SOLARIS || (defined(NetBSD) && (NetBSD <= 1991011) && (NetBSD >= 199603))
(void) sprintf(t, "%02d:%02d:%02d.%-.6ld %.*s @%hd ",
tm->tm_hour, tm->tm_min, tm->tm_sec, lp->usec,
(int)sizeof(lp->ifname), lp->ifname, lp->rule);
#else
for (len = 0; len < 3; len++)
if (!lp->ifname[len])
break;
if (lp->ifname[len])
len++;
(void) sprintf(t, "%02d:%02d:%02d.%-.6ld %*.*s%ld @%hd ",
tm->tm_hour, tm->tm_min, tm->tm_sec, lp->usec,
len, len, lp->ifname, lp->unit, lp->rule);
#endif
pr = getprotobynumber((int)p);
if (!pr) {
proto = pname;
sprintf(proto, "%d", (u_int)p);
} else
proto = pr->p_name;
if (lp->flags & (FI_SHORT << 20)) {
c[0] = 'S';
lvl = LOG_ERR;
} else if (lp->flags & FR_PASS) {
if (lp->flags & FR_LOGP)
c[0] = 'p';
else
c[0] = 'P';
lvl = LOG_NOTICE;
} else if (lp->flags & FR_BLOCK) {
if (lp->flags & FR_LOGB)
c[0] = 'b';
else
c[0] = 'B';
lvl = LOG_WARNING;
} else if (lp->flags & FF_LOGNOMATCH) {
c[0] = 'n';
lvl = LOG_NOTICE;
} else {
c[0] = 'L';
lvl = LOG_INFO;
}
c[1] = ' ';
c[2] = '\0';
(void) strcat(line, c);
t = line + strlen(line);
if ((p == IPPROTO_TCP || p == IPPROTO_UDP) && !(ip->ip_off & 0x1fff)) {
tp = (struct tcphdr *)((char *)ip + hl);
if (!(lp->flags & (FI_SHORT << 16))) {
(void) sprintf(t, "%s,%s -> ",
hostname(res, ip->ip_src),
portname(res, proto, tp->th_sport));
t += strlen(t);
(void) sprintf(t, "%s,%s PR %s len %hu %hu ",
hostname(res, ip->ip_dst),
portname(res, proto, tp->th_dport),
proto, hl, ip->ip_len);
t += strlen(t);
if (p == IPPROTO_TCP) {
*t++ = '-';
for (i = 0; tcpfl[i].value; i++)
if (tp->th_flags & tcpfl[i].value)
*t++ = tcpfl[i].flag;
}
if (opts & OPT_VERBOSE) {
(void) sprintf(t, " %lu %lu %hu",
(u_long)tp->th_seq,
(u_long)tp->th_ack, tp->th_win);
t += strlen(t);
}
*t = '\0';
} else {
(void) sprintf(t, "%s -> ", hostname(res, ip->ip_src));
t += strlen(t);
(void) sprintf(t, "%s PR %s len %hu %hu",
hostname(res, ip->ip_dst), proto,
hl, ip->ip_len);
}
} else if (p == IPPROTO_ICMP) {
ic = (struct icmp *)((char *)ip + hl);
(void) sprintf(t, "%s -> ", hostname(res, ip->ip_src));
t += strlen(t);
(void) sprintf(t, "%s PR icmp len %hu (%hu) icmp %d/%d",
hostname(res, ip->ip_dst), hl,
ip->ip_len, ic->icmp_type, ic->icmp_code);
if (ic->icmp_type == ICMP_UNREACH ||
ic->icmp_type == ICMP_SOURCEQUENCH ||
ic->icmp_type == ICMP_PARAMPROB ||
ic->icmp_type == ICMP_REDIRECT ||
ic->icmp_type == ICMP_TIMXCEED) {
ipc = &ic->icmp_ip;
tp = (struct tcphdr *)((char *)ipc + hl);
p = (u_short)ipc->ip_p;
pr = getprotobynumber((int)p);
if (!pr) {
proto = pname;
(void) sprintf(proto, "%d", (int)p);
} else
proto = pr->p_name;
t += strlen(t);
(void) sprintf(t, " for %s,%s -",
hostname(res, ipc->ip_src),
portname(res, proto, tp->th_sport));
t += strlen(t);
(void) sprintf(t, " %s,%s PR %s len %hu %hu",
hostname(res, ipc->ip_dst),
portname(res, proto, tp->th_dport),
proto, ipc->ip_hl << 2, ipc->ip_len);
}
} else {
(void) sprintf(t, "%s -> ", hostname(res, ip->ip_src));
t += strlen(t);
(void) sprintf(t, "%s PR %s len %hu (%hu)",
hostname(res, ip->ip_dst), proto, hl, ip->ip_len);
t += strlen(t);
if (ip->ip_off & 0x1fff)
(void) sprintf(t, " frag %s%s%hu@%hu",
ip->ip_off & IP_MF ? "+" : "",
ip->ip_off & IP_DF ? "-" : "",
ip->ip_len - hl, (ip->ip_off & 0x1fff) << 3);
}
t += strlen(t);
if (lp->flags & FR_KEEPSTATE) {
(void) strcpy(t, " K-S");
t += strlen(t);
}
if (lp->flags & FR_KEEPFRAG) {
(void) strcpy(t, " K-F");
t += strlen(t);
}
*t++ = '\n';
*t++ = '\0';
if (opts & OPT_SYSLOG)
syslog(lvl, "%s", line);
else
(void) fprintf(log, "%s", line);
if (opts & OPT_HEXHDR)
dumphex(log, buf, sizeof(struct ipl_ci));
if (opts & OPT_HEXBODY)
dumphex(log, ip, lp->plen + lp->hlen);
fflush(log);
}
int main(argc, argv)
int argc;
char *argv[];
{
FILE *log = NULL;
int fd = -1, flushed = 0, doread, n;
char buf[512], c, *iplfile = IPL_NAME;
extern int optind;
extern char *optarg;
while ((c = getopt(argc, argv, "Nf:FsvxX")) != -1)
switch (c)
{
case 'f' :
iplfile = optarg;
break;
case 'F' :
if ((fd == -1) &&
(fd = open(iplfile, O_RDWR)) == -1) {
(void) fprintf(stderr, "%s: ", IPL_NAME);
perror("open");
exit(-1);
}
if (ioctl(fd, SIOCIPFFB, &flushed) == 0) {
printf("%d bytes flushed from log buffer\n",
flushed);
fflush(stdout);
} else
perror("SIOCIPFFB");
break;
case 'N' :
opts |= OPT_RESOLVE;
break;
case 's' :
openlog(argv[0], LOG_NDELAY|LOG_PID, LOGFAC);
opts |= OPT_SYSLOG;
break;
case 'v' :
opts |= OPT_VERBOSE;
break;
case 'x' :
opts |= OPT_HEXBODY;
break;
case 'X' :
opts |= OPT_HEXHDR;
break;
}
if ((fd == -1) && (fd = open(iplfile, O_RDONLY)) == -1) {
(void) fprintf(stderr, "%s: ", IPL_NAME);
perror("open");
exit(-1);
}
if (!(opts & OPT_SYSLOG)) {
log = argv[optind] ? fopen(argv[optind], "a") : stdout;
setvbuf(log, NULL, _IONBF, 0);
}
if (flushed) {
if (opts & OPT_SYSLOG)
syslog(LOG_INFO, "%d bytes flushed from log\n",
flushed);
else
fprintf(log, "%d bytes flushed from log\n", flushed);
}
for (doread = 1; doread; )
switch (readlogentry(fd, &n, buf, sizeof(buf), log))
{
case -1 :
if (opts & OPT_SYSLOG)
syslog(LOG_ERR, "read: %m\n");
else
perror("read");
doread = 0;
break;
case 1 :
if (opts & OPT_SYSLOG)
syslog(LOG_ERR, "aborting logging\n");
else
fprintf(log, "aborting logging\n");
doread = 0;
break;
case 2 :
break;
case 0 :
printpacket(log, buf, n, opts);
break;
}
exit(0);
/* NOTREACHED */
}