1 /*        $NetBSD: etherfun.h,v 1.5 2011/02/02 17:53:41 chuck Exp $   */
2 
3 /*
4  * Copyright (c) 1995 Charles D. Cranor and Seth Widoff
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 /* etherfun.h */
28 
29 /* constants */
30 /* ether header */
31 #define ETYPE_RARP 0x8035  /* ethertype is RARP */
32 #define ETYPE_IP   0x800   /* ethertype is IP   */
33 
34 /* rev arp */
35 #define PTYPE_IP 0x800     /* Protocol type is IP      */
36 #define OPCODE_RARP 3      /* Optype is REVARP request */
37 #define OPCODE_REPLY 4     /* Optype is REVARP reply   */
38 
39 /* ip header */
40 #define  IPP_UDP 17        /* IP Protocol is UDP       */
41 #define  IP_VERSION 4      /* IP version number        */
42 #define  IP_HLEN 5         /* IP header length is a fixed 50 bytes */
43 #define N 1536
44 
45 /* tftp header */
46 #define FTPOP_ACKN 4      /* Opcode is acknowledge     */
47 #define FTPOP_ERR 5       /* Opcode is Error             */
48 #define FTP_PORT 69       /* Standard TFTP port number */
49 #define MSG "\0\1xxxxxxxx.147\0octet\0" /* implicit NULL */
50 
51 /* data structures */
52 
53 struct  ether_header {
54           u_char  ether_dhost[6];
55           u_char  ether_shost[6];
56           u_short ether_type;
57 };
58 
59 struct  ether_arp {
60           u_short ar_hrd;               /* format of hardware address */
61           u_short ar_pro;               /* format of protocol address */
62           u_char  ar_hln;               /* length of hardware address */
63           u_char  ar_pln;               /* length of protocol address */
64           u_short ar_op;
65           u_char  arp_sha[6]; /* sender hardware address */
66           u_char  arp_spa[4]; /* sender protocol address */
67           u_char  arp_tha[6]; /* target hardware address */
68           u_char  arp_tpa[4]; /* target protocol address */
69 };
70 
71 struct ip {
72           u_char  ip_v:4,                         /* version */
73                     ip_hl:4;            /* header length */
74           u_char  ip_tos;                         /* type of service */
75           short   ip_len;                         /* total length */
76           u_short ip_id;                          /* identification */
77           short   ip_off;                         /* fragment offset field */
78 #define IP_DF 0x4000                              /* dont fragment flag */
79 #define IP_MF 0x2000                              /* more fragments flag */
80 #define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
81           u_char  ip_ttl;                         /* time to live */
82           u_char  ip_p;                           /* protocol */
83           u_short ip_sum;                         /* checksum */
84           u_char  ip_src[4];
85           u_char  ip_dst[4];            /* source and dest address */
86 };
87 
88 struct udp {
89           u_short uh_sport;
90           u_short uh_dport;
91           short uh_ulen;
92           u_short uh_sum;
93 };
94 
95 struct tftph {
96           u_short op_code;
97           u_short block;
98 };
99 
100 struct tftphr {
101           struct tftph info;
102           char data[1];
103 };
104 
105 /* globals */
106 int last_ack;
107 u_char buf[N];
108 struct ether_header *eh = (struct ether_header *)buf;
109 struct ether_arp *rarp =
110     (struct ether_arp *)(buf + sizeof(struct ether_header));
111 struct ip *iph = (struct ip *)(buf + sizeof(struct ether_header));
112 struct udp *udph = (struct udp *)(buf + sizeof(struct ether_header) +
113     sizeof(struct ip));
114 u_char *tftp_r = buf + sizeof(struct ether_header) + sizeof(struct ip) +
115     sizeof(struct udp);
116 struct tftph *tftp_a = (struct tftph *)(buf + sizeof(struct ether_header) +
117     sizeof(struct ip) + sizeof(struct udp));
118 struct tftphr *tftp = (struct tftphr *)(buf + sizeof(struct ether_header) +
119     sizeof(struct ip) + sizeof(struct udp));
120