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/*
* ip.c
*
* Copyright (c) 2001 Dug Song <dugsong@monkey.org>
*
* $Id$
*/
#include "config.h"
#include <sys/types.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "dumbnet.h"
#include "aton.h"
#include "mod.h"
void
ip_usage(void)
{
fprintf(stderr, "Usage: dnet ip [tos|id|off|ttl|proto|src|dst "
"<value>] ... \n");
exit(1);
}
int
ip_main(int argc, char *argv[])
{
struct ip_hdr *ip;
struct addr addr;
u_char *p, buf[IP_LEN_MAX]; /* XXX */
char *name, *value;
int c, len;
srand(time(NULL));
ip = (struct ip_hdr *)buf;
ip->ip_hl = 5;
ip->ip_v = 4;
ip->ip_tos = 0;
ip->ip_id = rand() & 0xffff;
ip->ip_off = 0;
ip->ip_ttl = IP_TTL_MAX;
ip->ip_p = rand() & 0xff;
ip->ip_sum = 0;
ip->ip_src = rand();
ip->ip_dst = rand();
for (c = 1; c + 1 < argc; c += 2) {
name = argv[c];
value = argv[c + 1];
if (strcmp(name, "tos") == 0)
ip->ip_tos = atoi(value);
else if (strcmp(name, "id") == 0)
ip->ip_id = ntohs(atoi(value));
else if (strcmp(name, "off") == 0) {
if (off_aton(value, &ip->ip_off) < 0)
ip_usage();
} else if (strcmp(name, "ttl") == 0)
ip->ip_ttl = atoi(value);
else if (strcmp(name, "proto") == 0) {
if (proto_aton(value, &ip->ip_p) < 0)
ip_usage();
} else if (strcmp(name, "src") == 0) {
if (addr_aton(value, &addr) < 0)
ip_usage();
ip->ip_src = addr.addr_ip;
} else if (strcmp(name, "dst") == 0) {
if (addr_aton(value, &addr) < 0)
ip_usage();
ip->ip_dst = addr.addr_ip;
} else
ip_usage();
}
argc -= c;
argv += c;
if (argc != 0)
ip_usage();
if (isatty(STDIN_FILENO))
errx(1, "can't read IP payload from tty");
p = buf + IP_HDR_LEN;
len = sizeof(buf) - (p - buf);
while ((c = read(STDIN_FILENO, p, len)) > 0) {
p += c;
len -= c;
}
len = p - buf;
ip->ip_len = htons(len);
ip_checksum(buf, len);
if (write(STDOUT_FILENO, buf, len) != len)
err(1, "write");
return (0);
}
struct mod mod_ip = {
"ip",
MOD_TYPE_ENCAP,
ip_main
};
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