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-rw-r--r--contrib/isc-dhcp/common/packet.c321
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diff --git a/contrib/isc-dhcp/common/packet.c b/contrib/isc-dhcp/common/packet.c
deleted file mode 100644
index 6a15fcf1e4df6..0000000000000
--- a/contrib/isc-dhcp/common/packet.c
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@@ -1,321 +0,0 @@
-/* packet.c
-
- Packet assembly code, originally contributed by Archie Cobbs. */
-
-/*
- * Copyright (c) 1995, 1996, 1999 The Internet Software Consortium.
- * 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. Neither the name of The Internet Software Consortium nor the names
- * of its contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM 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 INTERNET SOFTWARE CONSORTIUM 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.
- *
- * This software has been written for the Internet Software Consortium
- * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
- * Enterprises. To learn more about the Internet Software Consortium,
- * see ``http://www.vix.com/isc''. To learn more about Vixie
- * Enterprises, see ``http://www.vix.com''.
- */
-
-#ifndef lint
-static char copyright[] =
-"$Id: packet.c,v 1.18.2.6 1999/06/10 00:58:16 mellon Exp $ Copyright (c) 1996 The Internet Software Consortium. All rights reserved.\n";
-#endif /* not lint */
-
-#include "dhcpd.h"
-
-#if defined (PACKET_ASSEMBLY) || defined (PACKET_DECODING)
-#include "includes/netinet/ip.h"
-#include "includes/netinet/udp.h"
-#endif /* PACKET_ASSEMBLY || PACKET_DECODING */
-
-/* Compute the easy part of the checksum on a range of bytes. */
-
-u_int32_t checksum (buf, nbytes, sum)
- unsigned char *buf;
- int nbytes;
- u_int32_t sum;
-{
- int i;
-
-#ifdef DEBUG_CHECKSUM
- debug ("checksum (%x %d %x)", buf, nbytes, sum);
-#endif
-
- /* Checksum all the pairs of bytes first... */
- for (i = 0; i < (nbytes & ~1); i += 2) {
-#ifdef DEBUG_CHECKSUM_VERBOSE
- debug ("sum = %x", sum);
-#endif
- sum += (u_int16_t) ntohs(*((u_int16_t *)(buf + i)));
- /* Add carry. */
- if (sum > 0xFFFF)
- sum -= 0xFFFF;
- }
-
- /* If there's a single byte left over, checksum it, too. Network
- byte order is big-endian, so the remaining byte is the high byte. */
- if (i < nbytes) {
-#ifdef DEBUG_CHECKSUM_VERBOSE
- debug ("sum = %x", sum);
-#endif
- sum += buf [i] << 8;
- /* Add carry. */
- if (sum > 0xFFFF)
- sum -= 0xFFFF;
- }
-
- return sum;
-}
-
-/* Finish computing the sum, and then put it into network byte order. */
-
-u_int32_t wrapsum (sum)
- u_int32_t sum;
-{
-#ifdef DEBUG_CHECKSUM
- debug ("wrapsum (%x)", sum);
-#endif
-
- sum = ~sum & 0xFFFF;
-#ifdef DEBUG_CHECKSUM_VERBOSE
- debug ("sum = %x", sum);
-#endif
-
-#ifdef DEBUG_CHECKSUM
- debug ("wrapsum returns %x", htons (sum));
-#endif
- return htons(sum);
-}
-
-#ifdef PACKET_ASSEMBLY
-/* Assemble an hardware header... */
-/* XXX currently only supports ethernet; doesn't check for other types. */
-
-void assemble_hw_header (interface, buf, bufix, to)
- struct interface_info *interface;
- unsigned char *buf;
- int *bufix;
- struct hardware *to;
-{
-#if defined (HAVE_TR_SUPPORT)
- if (interface -> hw_address.htype == HTYPE_IEEE802)
- assemble_tr_header (interface, buf, bufix, to);
- else
-#endif
- assemble_ethernet_header (interface, buf, bufix, to);
-
-}
-
-/* UDP header and IP header assembled together for convenience. */
-
-void assemble_udp_ip_header (interface, buf, bufix,
- from, to, port, data, len)
- struct interface_info *interface;
- unsigned char *buf;
- int *bufix;
- u_int32_t from;
- u_int32_t to;
- unsigned int port;
- unsigned char *data;
- int len;
-{
- struct ip ip;
- struct udphdr udp;
-
- /* Fill out the IP header */
- ip.ip_v = 4;
- ip.ip_hl = 5;
- ip.ip_tos = IPTOS_LOWDELAY;
- ip.ip_len = htons(sizeof(ip) + sizeof(udp) + len);
- ip.ip_id = 0;
- ip.ip_off = 0;
- ip.ip_ttl = 16;
- ip.ip_p = IPPROTO_UDP;
- ip.ip_sum = 0;
- ip.ip_src.s_addr = from;
- ip.ip_dst.s_addr = to;
-
- /* Checksum the IP header... */
- ip.ip_sum = wrapsum (checksum ((unsigned char *)&ip, sizeof ip, 0));
-
- /* Copy the ip header into the buffer... */
- memcpy (&buf [*bufix], &ip, sizeof ip);
- *bufix += sizeof ip;
-
- /* Fill out the UDP header */
- udp.uh_sport = local_port; /* XXX */
- udp.uh_dport = port; /* XXX */
- udp.uh_ulen = htons(sizeof(udp) + len);
- memset (&udp.uh_sum, 0, sizeof udp.uh_sum);
-
- /* Compute UDP checksums, including the ``pseudo-header'', the UDP
- header and the data. */
-
- udp.uh_sum =
- wrapsum (checksum ((unsigned char *)&udp, sizeof udp,
- checksum (data, len,
- checksum ((unsigned char *)
- &ip.ip_src,
- 2 * sizeof ip.ip_src,
- IPPROTO_UDP +
- (u_int32_t)
- ntohs (udp.uh_ulen)))));
-
- /* Copy the udp header into the buffer... */
- memcpy (&buf [*bufix], &udp, sizeof udp);
- *bufix += sizeof udp;
-}
-#endif /* PACKET_ASSEMBLY */
-
-#ifdef PACKET_DECODING
-/* Decode a hardware header... */
-
-ssize_t decode_hw_header (interface, buf, bufix, from)
- struct interface_info *interface;
- unsigned char *buf;
- int bufix;
- struct hardware *from;
-{
-#if defined (HAVE_TR_SUPPORT)
- if (interface -> hw_address.htype == HTYPE_IEEE802)
- return decode_tr_header (interface, buf, bufix, from);
- else
-#endif
- return decode_ethernet_header (interface, buf, bufix, from);
-}
-
-/* UDP header and IP header decoded together for convenience. */
-
-ssize_t decode_udp_ip_header (interface, buf, bufix, from, data, buflen)
- struct interface_info *interface;
- unsigned char *buf;
- int bufix;
- struct sockaddr_in *from;
- unsigned char *data;
- int buflen;
-{
- struct ip *ip;
- struct udphdr *udp;
- u_int32_t ip_len = (buf [bufix] & 0xf) << 2;
- u_int32_t sum, usum;
- static int ip_packets_seen;
- static int ip_packets_bad_checksum;
- static int udp_packets_seen;
- static int udp_packets_bad_checksum;
- static int udp_packets_length_checked;
- static int udp_packets_length_overflow;
- int len;
-
- ip = (struct ip *)(buf + bufix);
- udp = (struct udphdr *)(buf + bufix + ip_len);
-
-#ifdef USERLAND_FILTER
- /* Is it a UDP packet? */
- if (ip -> ip_p != IPPROTO_UDP)
- return -1;
-
- /* Is it to the port we're serving? */
- if (udp -> uh_dport != local_port)
- return -1;
-#endif /* USERLAND_FILTER */
-
- /* Check the IP header checksum - it should be zero. */
- ++ip_packets_seen;
- if (wrapsum (checksum (buf + bufix, ip_len, 0))) {
- ++ip_packets_bad_checksum;
- if (ip_packets_seen > 4 &&
- (ip_packets_seen / ip_packets_bad_checksum) < 2) {
- note ("%d bad IP checksums seen in %d packets",
- ip_packets_bad_checksum, ip_packets_seen);
- ip_packets_seen = ip_packets_bad_checksum = 0;
- }
- return -1;
- }
-
- /* Check the IP packet length. */
- if (ntohs (ip -> ip_len) != buflen)
- debug ("ip length %d disagrees with bytes received %d.",
- ntohs (ip -> ip_len), buflen);
-
- /* Copy out the IP source address... */
- memcpy (&from -> sin_addr, &ip -> ip_src, 4);
-
- /* Compute UDP checksums, including the ``pseudo-header'', the UDP
- header and the data. If the UDP checksum field is zero, we're
- not supposed to do a checksum. */
-
- if (!data) {
- data = buf + bufix + ip_len + sizeof *udp;
- len = ntohs (udp -> uh_ulen) - sizeof *udp;
- ++udp_packets_length_checked;
- if (len + data > buf + bufix + buflen) {
- ++udp_packets_length_overflow;
- if (udp_packets_length_checked > 4 &&
- (udp_packets_length_checked /
- udp_packets_length_overflow) < 2) {
- note ("%d udp packets in %d too long - dropped",
- udp_packets_length_overflow,
- udp_packets_length_checked);
- udp_packets_length_overflow =
- udp_packets_length_checked = 0;
- }
- return -1;
- }
- if (len + data != buf + bufix + buflen)
- debug ("accepting packet with data after udp payload.");
- }
-
- usum = udp -> uh_sum;
- udp -> uh_sum = 0;
-
- sum = wrapsum (checksum ((unsigned char *)udp, sizeof *udp,
- checksum (data, len,
- checksum ((unsigned char *)
- &ip -> ip_src,
- 2 * sizeof ip -> ip_src,
- IPPROTO_UDP +
- (u_int32_t)
- ntohs (udp -> uh_ulen)))));
-
- udp_packets_seen++;
- if (usum && usum != sum) {
- udp_packets_bad_checksum++;
- if (udp_packets_seen > 4 &&
- (udp_packets_seen / udp_packets_bad_checksum) < 2) {
- note ("%d bad udp checksums in %d packets",
- udp_packets_bad_checksum, udp_packets_seen);
- udp_packets_seen = udp_packets_bad_checksum = 0;
- }
- return -1;
- }
-
- /* Copy out the port... */
- memcpy (&from -> sin_port, &udp -> uh_sport, sizeof udp -> uh_sport);
-
- return ip_len + sizeof *udp;
-}
-#endif /* PACKET_DECODING */
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