blob: e900e5e33828e359403a85a225f18642cb3e924c [file] [log] [blame] [raw]
/*
* ipsend.c (C) 1995-1998 Darren Reed
*
* This was written to test what size TCP fragments would get through
* various TCP/IP packet filters, as used in IP firewalls. In certain
* conditions, enough of the TCP header is missing for unpredictable
* results unless the filter is aware that this can happen.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#ifdef __sgi
# include <sys/ptimers.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <string.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#ifndef linux
#include <netinet/ip_var.h>
#endif
#include "ipsend.h"
#if !defined(lint)
static const char sccsid[] = "@(#)ipsend.c 1.5 12/10/95 (C)1995 Darren Reed";
static const char rcsid[] = "@(#)$Id$";
#endif
extern char *optarg;
extern int optind;
extern void iplang __P((FILE *));
char options[68];
int opts;
#ifdef linux
char default_device[] = "eth0";
#else
# ifdef sun
char default_device[] = "le0";
# else
# ifdef ultrix
char default_device[] = "ln0";
# else
# ifdef __bsdi__
char default_device[] = "ef0";
# else
# ifdef __sgi
char default_device[] = "ec0";
# else
char default_device[] = "lan0";
# endif
# endif
# endif
# endif
#endif
static void usage __P((char *));
static void do_icmp __P((ip_t *, char *));
int main __P((int, char **));
static void usage(prog)
char *prog;
{
fprintf(stderr, "Usage: %s [options] dest [flags]\n\
\toptions:\n\
\t\t-d\tdebug mode\n\
\t\t-i device\tSend out on this device\n\
\t\t-f fragflags\tcan set IP_MF or IP_DF\n\
\t\t-g gateway\tIP gateway to use if non-local dest.\n\
\t\t-I code,type[,gw[,dst[,src]]]\tSet ICMP protocol\n\
\t\t-m mtu\t\tfake MTU to use when sending out\n\
\t\t-P protocol\tSet protocol by name\n\
\t\t-s src\t\tsource address for IP packet\n\
\t\t-T\t\tSet TCP protocol\n\
\t\t-t port\t\tdestination port\n\
\t\t-U\t\tSet UDP protocol\n\
\t\t-v\tverbose mode\n\
\t\t-w <window>\tSet the TCP window size\n\
", prog);
fprintf(stderr, "Usage: %s [-dv] -L <filename>\n\
\toptions:\n\
\t\t-d\tdebug mode\n\
\t\t-L filename\tUse IP language for sending packets\n\
\t\t-v\tverbose mode\n\
", prog);
exit(1);
}
static void do_icmp(ip, args)
ip_t *ip;
char *args;
{
struct icmp *ic;
char *s;
ip->ip_p = IPPROTO_ICMP;
ip->ip_len += sizeof(*ic);
ic = (struct icmp *)(ip + 1);
bzero((char *)ic, sizeof(*ic));
if (!(s = strchr(args, ',')))
{
fprintf(stderr, "ICMP args missing: ,\n");
return;
}
*s++ = '\0';
ic->icmp_type = atoi(args);
ic->icmp_code = atoi(s);
if (ic->icmp_type == ICMP_REDIRECT && strchr(s, ','))
{
char *t;
t = strtok(s, ",");
t = strtok(NULL, ",");
if (resolve(t, (char *)&ic->icmp_gwaddr) == -1)
{
fprintf(stderr,"Cant resolve %s\n", t);
exit(2);
}
if ((t = strtok(NULL, ",")))
{
if (resolve(t, (char *)&ic->icmp_ip.ip_dst) == -1)
{
fprintf(stderr,"Cant resolve %s\n", t);
exit(2);
}
if ((t = strtok(NULL, ",")))
{
if (resolve(t,
(char *)&ic->icmp_ip.ip_src) == -1)
{
fprintf(stderr,"Cant resolve %s\n", t);
exit(2);
}
}
}
}
}
int send_packets(dev, mtu, ip, gwip)
char *dev;
int mtu;
ip_t *ip;
struct in_addr gwip;
{
u_short sport = 0;
int wfd;
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)
sport = ((struct tcpiphdr *)ip)->ti_sport;
wfd = initdevice(dev, sport, 5);
return send_packet(wfd, mtu, ip, gwip);
}
int main(argc, argv)
int argc;
char **argv;
{
FILE *langfile = NULL;
struct tcpiphdr *ti;
struct in_addr gwip;
tcphdr_t *tcp;
ip_t *ip;
char *name = argv[0], host[MAXHOSTNAMELEN + 1];
char *gateway = NULL, *dev = NULL;
char *src = NULL, *dst, *s;
int mtu = 1500, olen = 0, c, nonl = 0;
/*
* 65535 is maximum packet size...you never know...
*/
ip = (ip_t *)calloc(1, 65536);
ti = (struct tcpiphdr *)ip;
tcp = (tcphdr_t *)&ti->ti_sport;
ip->ip_len = sizeof(*ip);
ip->ip_hl = sizeof(*ip) >> 2;
while ((c = getopt(argc, argv, "I:L:P:TUdf:i:g:m:o:s:t:vw:")) != -1)
switch (c)
{
case 'I' :
nonl++;
if (ip->ip_p)
{
fprintf(stderr, "Protocol already set: %d\n",
ip->ip_p);
break;
}
do_icmp(ip, optarg);
break;
case 'L' :
if (nonl) {
fprintf(stderr,
"Incorrect usage of -L option.\n");
usage(name);
}
if (!strcmp(optarg, "-"))
langfile = stdin;
else if (!(langfile = fopen(optarg, "r"))) {
fprintf(stderr, "can't open file %s\n",
optarg);
exit(1);
}
iplang(langfile);
return 0;
case 'P' :
{
struct protoent *p;
nonl++;
if (ip->ip_p)
{
fprintf(stderr, "Protocol already set: %d\n",
ip->ip_p);
break;
}
if ((p = getprotobyname(optarg)))
ip->ip_p = p->p_proto;
else
fprintf(stderr, "Unknown protocol: %s\n",
optarg);
break;
}
case 'T' :
nonl++;
if (ip->ip_p)
{
fprintf(stderr, "Protocol already set: %d\n",
ip->ip_p);
break;
}
ip->ip_p = IPPROTO_TCP;
ip->ip_len += sizeof(tcphdr_t);
break;
case 'U' :
nonl++;
if (ip->ip_p)
{
fprintf(stderr, "Protocol already set: %d\n",
ip->ip_p);
break;
}
ip->ip_p = IPPROTO_UDP;
ip->ip_len += sizeof(udphdr_t);
break;
case 'd' :
opts |= OPT_DEBUG;
break;
case 'f' :
nonl++;
ip->ip_off = strtol(optarg, NULL, 0);
break;
case 'g' :
nonl++;
gateway = optarg;
break;
case 'i' :
nonl++;
dev = optarg;
break;
case 'm' :
nonl++;
mtu = atoi(optarg);
if (mtu < 28)
{
fprintf(stderr, "mtu must be > 28\n");
exit(1);
}
break;
case 'o' :
nonl++;
olen = buildopts(optarg, options, (ip->ip_hl - 5) << 2);
break;
case 's' :
nonl++;
src = optarg;
break;
case 't' :
nonl++;
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)
tcp->th_dport = htons(atoi(optarg));
break;
case 'v' :
opts |= OPT_VERBOSE;
break;
case 'w' :
nonl++;
if (ip->ip_p == IPPROTO_TCP)
tcp->th_win = atoi(optarg);
else
fprintf(stderr, "set protocol to TCP first\n");
break;
default :
fprintf(stderr, "Unknown option \"%c\"\n", c);
usage(name);
}
if (argc - optind < 1)
usage(name);
dst = argv[optind++];
if (!src)
{
gethostname(host, sizeof(host));
src = host;
}
if (resolve(src, (char *)&ip->ip_src) == -1)
{
fprintf(stderr,"Cant resolve %s\n", src);
exit(2);
}
if (resolve(dst, (char *)&ip->ip_dst) == -1)
{
fprintf(stderr,"Cant resolve %s\n", dst);
exit(2);
}
if (!gateway)
gwip = ip->ip_dst;
else if (resolve(gateway, (char *)&gwip) == -1)
{
fprintf(stderr,"Cant resolve %s\n", gateway);
exit(2);
}
if (olen)
{
caddr_t ipo = (caddr_t)ip;
printf("Options: %d\n", olen);
ti = (struct tcpiphdr *)malloc(olen + ip->ip_len);
if(!ti)
{
fprintf(stderr,"malloc failed\n");
exit(2);
}
bcopy((char *)ip, (char *)ti, sizeof(*ip));
ip = (ip_t *)ti;
ip->ip_hl = (olen >> 2);
bcopy(options, (char *)(ip + 1), olen);
bcopy((char *)tcp, (char *)(ip + 1) + olen, sizeof(*tcp));
ip->ip_len += olen;
bcopy((char *)ip, (char *)ipo, ip->ip_len);
ip = (ip_t *)ipo;
tcp = (tcphdr_t *)((char *)(ip + 1) + olen);
}
if (ip->ip_p == IPPROTO_TCP)
for (s = argv[optind]; s && (c = *s); s++)
switch(c)
{
case 'S' : case 's' :
tcp->th_flags |= TH_SYN;
break;
case 'A' : case 'a' :
tcp->th_flags |= TH_ACK;
break;
case 'F' : case 'f' :
tcp->th_flags |= TH_FIN;
break;
case 'R' : case 'r' :
tcp->th_flags |= TH_RST;
break;
case 'P' : case 'p' :
tcp->th_flags |= TH_PUSH;
break;
case 'U' : case 'u' :
tcp->th_flags |= TH_URG;
break;
}
if (!dev)
dev = default_device;
printf("Device: %s\n", dev);
printf("Source: %s\n", inet_ntoa(ip->ip_src));
printf("Dest: %s\n", inet_ntoa(ip->ip_dst));
printf("Gateway: %s\n", inet_ntoa(gwip));
if (ip->ip_p == IPPROTO_TCP && tcp->th_flags)
printf("Flags: %#x\n", tcp->th_flags);
printf("mtu: %d\n", mtu);
#ifdef DOSOCKET
if (tcp->th_dport)
return do_socket(dev, mtu, ti, gwip);
#endif
return send_packets(dev, mtu, (ip_t *)ti, gwip);
}