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/* $OpenBSD: etherfun.c,v 1.4 1997/01/29 07:58:37 deraadt Exp $ */
/*
*
* 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.c */
#include <sys/cdefs.h>
#include <stand.h>
#include "sboot.h"
#include "etherfun.h"
/* Construct and send a rev arp packet */
void
do_rev_arp()
{
int i;
for (i = 0; i < 6; i++)
eh->ether_dhost[i] = 0xff;
bcopy(myea, eh->ether_shost, 6);
eh->ether_type = ETYPE_RARP;
rarp->ar_hrd = 1; /* hardware type is 1 */
rarp->ar_pro = PTYPE_IP;
rarp->ar_hln = 6; /* length of hardware address is 6 bytes */
rarp->ar_pln = 4; /* length of ip address is 4 byte */
rarp->ar_op = OPCODE_RARP;
bcopy(myea, rarp->arp_sha, sizeof(myea));
bcopy(myea, rarp->arp_tha, sizeof(myea));
for (i = 0; i < 4; i++)
rarp->arp_spa[i] = rarp->arp_tpa[i] = 0x00;
le_put(buf, 76);
}
/* Receive and disassemble the rev_arp reply */
int
get_rev_arp()
{
le_get(buf, sizeof(buf), 6);
if (eh->ether_type == ETYPE_RARP && rarp->ar_op == OPCODE_REPLY) {
bcopy(rarp->arp_tpa, myip, sizeof(rarp->arp_tpa));
bcopy(rarp->arp_spa, servip, sizeof(rarp->arp_spa));
bcopy(rarp->arp_sha, servea, sizeof(rarp->arp_sha));
return (1);
}
return (0);
}
/* Try to get a reply to a rev arp request */
int
rev_arp()
{
int tries = 0;
while (tries < 5) {
do_rev_arp();
if (get_rev_arp())
return (1);
tries++;
}
return (0);
}
/*
* Send a tftp read request or acknowledgement
* mesgtype 0 is a read request, 1 is an
* acknowledgement
*/
void
do_send_tftp(mesgtype)
int mesgtype;
{
u_long res, iptmp, lcv;
char *tot;
if (mesgtype == 0) {
tot = tftp_r + (sizeof(MSG) - 1);
myport = (u_short) ttime();
if (myport < 1000)
myport += 1000;
servport = FTP_PORT; /* to start */
} else {
tot = (char *) tftp_a + 4;
}
bcopy(servea, eh->ether_dhost, sizeof(servea));
bcopy(myea, eh->ether_shost, sizeof(myea));
eh->ether_type = ETYPE_IP;
iph->ip_v = IP_VERSION;
iph->ip_hl = IP_HLEN;
iph->ip_tos = 0; /* type of service is 0 */
iph->ip_id = 0; /* id field is 0 */
iph->ip_off = IP_DF;
iph->ip_ttl = 3; /* time to live is 3 seconds/hops */
iph->ip_p = IPP_UDP;
bcopy(myip, iph->ip_src, sizeof(myip));
bcopy(servip, iph->ip_dst, sizeof(servip));
iph->ip_sum = 0;
iph->ip_len = tot - (char *) iph;
res = oc_cksum(iph, sizeof(struct ip), 0);
iph->ip_sum = 0xffff & ~res;
udph->uh_sport = myport;
udph->uh_dport = servport;
udph->uh_sum = 0;
if (mesgtype) {
tftp_a->op_code = FTPOP_ACKN;
tftp_a->block = (u_short) (mesgtype);
} else {
bcopy(myip, &iptmp, sizeof(iptmp));
bcopy(MSG, tftp_r, (sizeof(MSG) - 1));
for (lcv = 9; lcv >= 2; lcv--) {
tftp_r[lcv] = "0123456789ABCDEF"[iptmp & 0xF];
iptmp = iptmp >> 4;
}
}
udph->uh_ulen = tot - (char *) udph;
le_put(buf, tot - buf);
}
/* Attempt to tftp a file and read it into memory */
int
do_get_file()
{
int fail = 0, oldlen;
char *loadat = (char *) LOAD_ADDR;
last_ack = 0;
do_send_tftp(READ);
while (1) {
if (le_get(buf, sizeof(buf), 5) == 0) {
/* timeout occured */
if (last_ack)
do_send_tftp(last_ack);
else
do_send_tftp(READ);
fail++;
if (fail > 5) {
printf("\n");
return (1);
}
} else {
printf("%x \r", tftp->info.block * 512);
if ((eh->ether_type != ETYPE_IP) || (iph->ip_p != IPP_UDP)) {
fail++;
continue;
}
if (servport == FTP_PORT)
servport = udph->uh_sport;
if (tftp->info.op_code == FTPOP_ERR) {
printf("TFTP: Download error %d: %s\n",
tftp->info.block, tftp->data);
return (1);
}
if (tftp->info.block != last_ack + 1) {
/* we received the wrong block */
if (tftp->info.block < last_ack + 1) {
/* nack whatever we received */
do_send_tftp(tftp->info.block);
} else {
/* nack the last confirmed block */
do_send_tftp(last_ack);
}
fail++;
} else {/* we got the right block */
fail = 0;
last_ack++;
oldlen = udph->uh_ulen;
do_send_tftp(last_ack);
/* printf("bcopy %x %x %d\n", &tftp->data,
* loadat, oldlen - 12); */
bcopy(&tftp->data, loadat, oldlen - 12);
loadat += oldlen - 12;
if (oldlen < (8 + 4 + 512)) {
printf("\n");
return (0);
}
}
}
}
printf("\n");
return (0);
}
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