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/*
*
* Copyright (c) 1995 Charles D. Cranor and Seth Widoff
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Charles D. Cranor
* and Seth Widoff.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
/* etherfun.h */
/* constants */
/* ether header */
#define ETYPE_RARP 0x8035 /* ethertype is RARP */
#define ETYPE_IP 0x800 /* ethertype is IP */
/* rev arp */
#define PTYPE_IP 0x800 /* Protocol type is IP */
#define OPCODE_RARP 3 /* Optype is REVARP request */
#define OPCODE_REPLY 4 /* Optype is REVARP reply */
/* ip header */
#define IPP_UDP 17 /* IP Protocol is UDP */
#define IP_VERSION 4 /* IP version number */
#define IP_HLEN 5 /* IP header length is a fixed 50 bytes */
#define N 1536
/* tftp header */
#define FTPOP_ACKN 4 /* Opcode is acknowledge */
#define FTPOP_ERR 5 /* Opcode is Error */
#define FTP_PORT 69 /* Standard TFTP port number */
#define MSG "\0\1xxxxxxxx.147\0octet\0" /* implicit NULL */
/* data structures */
struct ether_header {
u_char ether_dhost[6];
u_char ether_shost[6];
u_short ether_type;
};
struct ether_arp {
u_short ar_hrd; /* format of hardware address */
u_short ar_pro; /* format of protocol address */
u_char ar_hln; /* length of hardware address */
u_char ar_pln; /* length of protocol address */
u_short ar_op;
u_char arp_sha[6]; /* sender hardware address */
u_char arp_spa[4]; /* sender protocol address */
u_char arp_tha[6]; /* target hardware address */
u_char arp_tpa[4]; /* target protocol address */
};
struct ip {
u_char ip_v:4, /* version */
ip_hl:4; /* header length */
u_char ip_tos; /* type of service */
short ip_len; /* total length */
u_short ip_id; /* identification */
short ip_off; /* fragment offset field */
#define IP_DF 0x4000 /* dont fragment flag */
#define IP_MF 0x2000 /* more fragments flag */
#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
u_char ip_ttl; /* time to live */
u_char ip_p; /* protocol */
u_short ip_sum; /* checksum */
u_char ip_src[4];
u_char ip_dst[4]; /* source and dest address */
};
struct udp {
u_short uh_sport;
u_short uh_dport;
short uh_ulen;
u_short uh_sum;
};
struct tftph {
u_short op_code;
u_short block;
};
struct tftphr {
struct tftph info;
char data[1];
};
/* globals */
int last_ack;
char buf[N];
struct ether_header *eh = (struct ether_header *)buf;
struct ether_arp *rarp =
(struct ether_arp *)(buf + sizeof(struct ether_header));
struct ip *iph = (struct ip *)(buf + sizeof(struct ether_header));
struct udp *udph = (struct udp *)(buf + sizeof(struct ether_header) +
sizeof(struct ip));
char *tftp_r = buf + sizeof(struct ether_header) + sizeof(struct ip) +
sizeof(struct udp);
struct tftph *tftp_a = (struct tftph *)(buf + sizeof(struct ether_header) +
sizeof(struct ip) + sizeof(struct udp));
struct tftphr *tftp = (struct tftphr *)(buf + sizeof(struct ether_header) +
sizeof(struct ip) + sizeof(struct udp));
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