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/*
* Regression test for bugs in ipv4 ip_offset and h_len handling, such as
* http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=418975
*
* Copyright (c) 2009 Sam Roberts <sroberts@wurldtech.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#if (HAVE_CONFIG_H)
#include "../include/config.h"
#endif
#include "./libnet_test.h"
#include <assert.h>
static void print_pblocks(libnet_t* l)
{
libnet_pblock_t* p = l->protocol_blocks;
while(p) {
/* h_len is header length for checksumming? "chksum length"? */
printf(" tag %d flags %d type %20s/%#x buf %p b_len %2u h_len %2u copied %2u\n",
p->ptag, p->flags,
libnet_diag_dump_pblock_type(p->type), p->type,
p->buf, p->b_len, p->h_len, p->copied);
p = p->next;
}
printf(" link_offset %d aligner %d total_size %u nblocks %d\n",
l->link_offset, l->aligner, l->total_size, l->n_pblocks);
}
static int build_ipv4(libnet_t* l, libnet_ptag_t ip_ptag, int payload_s)
{
u_long src_ip = 0xf101f1f1;
u_long dst_ip = 0xf102f1f1;
uint8_t* payload = malloc(payload_s);
assert(payload);
memset(payload, '\x00', payload_s);
ip_ptag = libnet_build_ipv4(
LIBNET_IPV4_H + payload_s, /* length */
0, /* TOS */
0xbbbb, /* IP ID */
0, /* IP Frag */
0xcc, /* TTL */
IPPROTO_UDP, /* protocol */
0, /* checksum */
src_ip, /* source IP */
dst_ip, /* destination IP */
payload, /* payload */
payload_s, /* payload size */
l, /* libnet handle */
ip_ptag); /* libnet id */
assert(ip_ptag > 0);
free(payload);
return ip_ptag;
}
int
main(int argc, char *argv[])
{
libnet_t *l;
int r;
char *device = "eth0";
uint8_t enet_src[6] = {0x11, 0x11, 0x11, 0x11, 0x11, 0x11};
uint8_t enet_dst[6] = {0x22, 0x22, 0x22, 0x22, 0x22, 0x22};
char errbuf[LIBNET_ERRBUF_SIZE];
libnet_ptag_t ip_ptag = 0;
libnet_ptag_t eth_ptag = 0;
int pkt1_payload = 10;
uint8_t* pkt1 = NULL;
uint32_t pkt1_sz = 0;
struct libnet_ipv4_hdr* h1;
int pkt2_payload = 2;
uint8_t* pkt2 = NULL;
uint32_t pkt2_sz = 0;
struct libnet_ipv4_hdr* h2;
l = libnet_init( LIBNET_LINK, device, errbuf);
assert(l);
/* Bug is triggered when rebuilding the ipv4 blocks with smaller payload.
* If change in payload size is larger than 20 (iph) + 14 (ether) +
* aligner, it will cause checksum to be written into the unallocated
* memory before the packet, possibly corrupting glib's memory allocation
* structures.
*/
printf("Packet 1:\n");
ip_ptag = build_ipv4(l, ip_ptag, pkt1_payload);
eth_ptag = libnet_build_ethernet(
enet_dst, /* ethernet destination */
enet_src, /* ethernet source */
ETHERTYPE_IP, /* protocol type */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
assert(eth_ptag > 0);
r = libnet_pblock_coalesce(l, &pkt1, &pkt1_sz);
assert(r >= 0);
print_pblocks(l);
libnet_diag_dump_hex(pkt1, 14, 0, stdout);
libnet_diag_dump_hex(pkt1+14, pkt1_sz-14, 0, stdout);
printf("Packet 2:\n");
ip_ptag = build_ipv4(l, ip_ptag, pkt2_payload);
r = libnet_pblock_coalesce(l, &pkt2, &pkt2_sz);
assert(r >= 0);
print_pblocks(l);
libnet_diag_dump_hex(pkt2, 14, 0, stdout);
libnet_diag_dump_hex(pkt2+14, pkt2_sz-14, 0, stdout);
/* Packets should differ only in the total length and cksum. */
h1 = (struct libnet_ipv4_hdr*) (pkt1+14);
h2 = (struct libnet_ipv4_hdr*) (pkt2+14);
assert(h1->ip_len == htons(20+pkt1_payload));
assert(h2->ip_len == htons(20+pkt2_payload));
h1->ip_len = h2->ip_len = 0x5555;
h1->ip_sum = h2->ip_sum = 0x6666;
assert(memcmp(pkt1, pkt2, 14 + 20) == 0);
return (EXIT_SUCCESS);
}
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