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1.1.6

    1: /*
    2:  * Regression test for bugs in ipv4 ip_offset and h_len handling, such as
    3:  *   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=418975
    4:  *
    5:  * Copyright (c) 2009 Sam Roberts <sroberts@wurldtech.com>
    6:  * All rights reserved.
    7:  *
    8:  * Redistribution and use in source and binary forms, with or without
    9:  * modification, are permitted provided that the following conditions
   10:  * are met:
   11:  * 1. Redistributions of source code must retain the above copyright
   12:  *    notice, this list of conditions and the following disclaimer.
   13:  * 2. Redistributions in binary form must reproduce the above copyright
   14:  *    notice, this list of conditions and the following disclaimer in the
   15:  *    documentation and/or other materials provided with the distribution.
   16:  *
   17:  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27:  * SUCH DAMAGE.
   28:  *
   29:  */
   30: #if (HAVE_CONFIG_H)
   31: #include "../include/config.h"
   32: #endif
   33: #include "./libnet_test.h"
   34: 
   35: #include <assert.h>
   36: 
   37: static void print_pblocks(libnet_t* l)
   38: {
   39:     libnet_pblock_t* p = l->protocol_blocks;
   40: 
   41:     while(p) {
   42:         /* h_len is header length for checksumming? "chksum length"? */
   43:         printf("  tag %d flags %d type %20s/%#x buf %p b_len %2u h_len %2u copied %2u\n",
   44:                 p->ptag, p->flags,
   45:                 libnet_diag_dump_pblock_type(p->type), p->type,
   46:                 p->buf, p->b_len, p->h_len, p->copied);
   47:         p = p->next;
   48:     }
   49:     printf("  link_offset %d aligner %d total_size %u nblocks %d\n",
   50:             l->link_offset, l->aligner, l->total_size, l->n_pblocks);
   51: 
   52: }
   53: 
   54: static int build_ipv4(libnet_t* l, libnet_ptag_t ip_ptag, int payload_s)
   55: {
   56:     u_long src_ip = 0xf101f1f1;
   57:     u_long dst_ip = 0xf102f1f1;
   58:     uint8_t* payload = malloc(payload_s);
   59:     assert(payload);
   60:     memset(payload, '\x00', payload_s);
   61: 
   62:     ip_ptag = libnet_build_ipv4(
   63:         LIBNET_IPV4_H + payload_s,                  /* length */
   64:         0,                                          /* TOS */
   65:         0xbbbb,                                     /* IP ID */
   66:         0,                                          /* IP Frag */
   67:         0xcc,                                      /* TTL */
   68:         IPPROTO_UDP,                                /* protocol */
   69:         0,                                          /* checksum */
   70:         src_ip,                                     /* source IP */
   71:         dst_ip,                                     /* destination IP */
   72:         payload,                                    /* payload */
   73:         payload_s,                                  /* payload size */
   74:         l,                                          /* libnet handle */
   75:         ip_ptag);                                   /* libnet id */
   76: 
   77:     assert(ip_ptag > 0);
   78: 
   79:     free(payload);
   80: 
   81:     return ip_ptag;
   82: }
   83: 
   84: int
   85: main(int argc, char *argv[])
   86: {
   87:     libnet_t *l;
   88:     int r;
   89:     char *device = "eth0";
   90:     uint8_t enet_src[6] = {0x11, 0x11, 0x11, 0x11, 0x11, 0x11};
   91:     uint8_t enet_dst[6] = {0x22, 0x22, 0x22, 0x22, 0x22, 0x22};
   92:     char errbuf[LIBNET_ERRBUF_SIZE];
   93:     libnet_ptag_t ip_ptag = 0;
   94:     libnet_ptag_t eth_ptag = 0;
   95:     int pkt1_payload = 10;
   96:     uint8_t* pkt1 = NULL;
   97:     uint32_t pkt1_sz = 0;
   98:     struct libnet_ipv4_hdr* h1;
   99:     int pkt2_payload = 2;
  100:     uint8_t* pkt2 = NULL;
  101:     uint32_t pkt2_sz = 0;
  102:     struct libnet_ipv4_hdr* h2;
  103: 
  104: 
  105: 
  106:     l = libnet_init( LIBNET_LINK, device, errbuf);
  107: 
  108:     assert(l);
  109: 
  110:     /* Bug is triggered when rebuilding the ipv4 blocks with smaller payload.
  111:      * If change in payload size is larger than 20 (iph) + 14 (ether) +
  112:      * aligner, it will cause checksum to be written into the unallocated
  113:      * memory before the packet, possibly corrupting glib's memory allocation
  114:      * structures.
  115:      */
  116: 
  117:     printf("Packet 1:\n");
  118: 
  119:     ip_ptag = build_ipv4(l, ip_ptag, pkt1_payload);
  120: 
  121:     eth_ptag = libnet_build_ethernet(
  122:         enet_dst,                                      /* ethernet destination */
  123:         enet_src,                                      /* ethernet source */
  124:         ETHERTYPE_IP,                               /* protocol type */
  125:         NULL,                                       /* payload */
  126:         0,                                          /* payload size */
  127:         l,                                          /* libnet handle */
  128:         0);                                         /* libnet id */
  129:     assert(eth_ptag > 0);
  130: 
  131:     r = libnet_pblock_coalesce(l, &pkt1, &pkt1_sz);
  132:     assert(r >= 0);
  133: 
  134:     print_pblocks(l);
  135: 
  136:     libnet_diag_dump_hex(pkt1, 14, 0, stdout);
  137:     libnet_diag_dump_hex(pkt1+14, pkt1_sz-14, 0, stdout);
  138: 
  139:     printf("Packet 2:\n");
  140: 
  141:     ip_ptag = build_ipv4(l, ip_ptag, pkt2_payload);
  142: 
  143:     r = libnet_pblock_coalesce(l, &pkt2, &pkt2_sz);
  144:     assert(r >= 0);
  145: 
  146:     print_pblocks(l);
  147: 
  148:     libnet_diag_dump_hex(pkt2, 14, 0, stdout);
  149:     libnet_diag_dump_hex(pkt2+14, pkt2_sz-14, 0, stdout);
  150: 
  151:     /* Packets should differ only in the total length and cksum. */
  152:     h1 = (struct libnet_ipv4_hdr*) (pkt1+14);
  153:     h2 = (struct libnet_ipv4_hdr*) (pkt2+14);
  154: 
  155:     assert(h1->ip_len == htons(20+pkt1_payload));
  156:     assert(h2->ip_len == htons(20+pkt2_payload));
  157: 
  158:     h1->ip_len = h2->ip_len = 0x5555;
  159:     h1->ip_sum = h2->ip_sum = 0x6666;
  160: 
  161:     assert(memcmp(pkt1, pkt2, 14 + 20) == 0);
  162: 
  163:     return (EXIT_SUCCESS);
  164: }
  165: