diff options
Diffstat (limited to 'libnet/sample/ntp.c')
| -rw-r--r-- | libnet/sample/ntp.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/libnet/sample/ntp.c b/libnet/sample/ntp.c new file mode 100644 index 0000000..0fef46f --- /dev/null +++ b/libnet/sample/ntp.c @@ -0,0 +1,193 @@ +/* + * $Id: ntp.c,v 1.3 2004/02/20 18:53:49 mike Exp $ + * + * libnet 1.1 + * Build an NTP Packet + * + * Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.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" + +int +main(int argc, char **argv) +{ + int c; + libnet_t *l; + u_long dst_ip; + libnet_ptag_t t; + char errbuf[LIBNET_ERRBUF_SIZE]; + + printf("libnet 1.1 NTP packet shaping[raw -- autobuilding IP]\n"); + + /* + * Initialize the library. Root priviledges are required. + */ + l = libnet_init( + LIBNET_RAW4, /* injection type */ + NULL, /* network interface */ + errbuf); /* error buf */ + + if (l == NULL) + { + fprintf(stderr, "libnet_init() failed: %s", errbuf); + exit(EXIT_FAILURE); + } + + dst_ip = 0; + while((c = getopt(argc, argv, "d:")) != EOF) + { + switch (c) + { + /* + * We expect the input to be of the form `ip.ip.ip.ip.port`. We + * point cp to the last dot of the IP address/port string and + * then seperate them with a NULL byte. The optarg now points to + * just the IP address, and cp points to the port. + */ + case 'd': + if ((dst_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1) + { + fprintf(stderr, "Bad destination IP address: %s\n", optarg); + exit(1); + } + break; + } + } + if (!dst_ip) + { + usage(argv[0]); + exit(EXIT_FAILURE); + } + + /* + * Build the packet, remmebering that order IS important. We must + * build the packet from lowest protocol type on up as it would + * appear on the wire. So for our NTP packet: + * + * -------------------------------------------------------------------- + * | IP | UDP | NTP | + * -------------------------------------------------------------------- + * ^ ^ ^ + * |-------------- | | + * libnet_build_ipv4()--| | | + * | | + * libnet_build_udp()-------| | + * | + * libnet_build_ntp()------------------------------| + */ + t = libnet_build_ntp( + LIBNET_NTP_LI_AC, /* leap indicator */ + LIBNET_NTP_VN_4, /* version */ + LIBNET_NTP_MODE_S, /* mode */ + LIBNET_NTP_STRATUM_PRIMARY, /* stratum */ + 4, /* poll interval */ + 1, /* precision */ + 0xffff, /* delay interval */ + 0xffff, /* delay fraction */ + 0xffff, /* dispersion interval */ + 0xffff, /* dispersion fraction */ + LIBNET_NTP_REF_PPS, /* reference id */ + 0x11, /* reference ts int */ + 0x22, /* reference ts frac */ + 0x33, /* originate ts int */ + 0x44, /* originate ts frac */ + 0x55, /* receive ts int */ + 0x66, /* receive ts frac */ + 0x77, /* transmit ts interval */ + 0x88, /* transmit ts fraction */ + NULL, /* payload */ + 0, /* payload size */ + l, /* libnet handle */ + 0); /* libnet id */ + if (t == -1) + { + fprintf(stderr, "Can't build NTP header: %s\n", libnet_geterror(l)); + goto bad; + } + + libnet_seed_prand(l); + t = libnet_build_udp( + libnet_get_prand(LIBNET_PRu16), /* source port */ + 123, /* NTP port */ + LIBNET_UDP_H + LIBNET_NTP_H, /* UDP packet length */ + 0, /* checksum */ + NULL, /* payload */ + 0, /* payload size */ + l, /* libnet handle */ + 0); /* libnet id */ + if (t == -1) + { + fprintf(stderr, "Can't build UDP header: %s\n", libnet_geterror(l)); + goto bad; + } + + t = libnet_autobuild_ipv4( + LIBNET_IPV4_H + LIBNET_UDP_H + LIBNET_NTP_H,/* packet length */ + IPPROTO_UDP, + dst_ip, + l); + if (t == -1) + { + fprintf(stderr, "Can't build IP header: %s\n", libnet_geterror(l)); + goto bad; + } + + /* + * Write it to the wire. + */ + + fprintf(stderr, "l contains a %d byte packet\n", libnet_getpacket_size(l)); + c = libnet_write(l); + if (c == -1) + { + fprintf(stderr, "Write error: %s\n", libnet_geterror(l)); + goto bad; + } + else + { + fprintf(stderr, "Wrote %d byte NTP packet; check the wire.\n", c); + } + libnet_destroy(l); + return (EXIT_SUCCESS); +bad: + libnet_destroy(l); + return (EXIT_FAILURE); +} + + +void +usage(char *name) +{ + fprintf(stderr, + "usage: %s -d destination_ip\n", + name); +} + +/* EOF */ |