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- /* $Id: edit_packet.c 2211 2009-02-18 02:48:04Z aturner $ */
- /*
- * Copyright (c) 2001-2007 Aaron Turner.
- * 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 names of the copyright owners 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 ``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 AUTHORS OR COPYRIGHT HOLDERS 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.
- */
- #include "config.h"
- #include "defines.h"
- #include "common.h"
- #include "tcpedit-int.h"
- #include "edit_packet.h"
- #include "checksum.h"
- #include "lib/sll.h"
- #include "dlt.h"
- #include <string.h>
- #include <stdlib.h>
- #include <sys/types.h>
- #include <sys/socket.h>
- #include <netinet/in.h>
- #include <arpa/inet.h>
- static u_int32_t randomize_ipv4_addr(tcpedit_t *tcpedit, u_int32_t ip);
- static u_int32_t remap_ipv4(tcpedit_t *tcpedit, tcpr_cidr_t *cidr, const u_int32_t original);
- static int is_unicast_ipv4(tcpedit_t *tcpedit, u_int32_t ip);
- /**
- * this code re-calcs the IP and Layer 4 checksums
- * the IMPORTANT THING is that the Layer 4 header
- * is contiguious in memory after *ip_hdr we're actually
- * writing to the layer 4 header via the ip_hdr ptr.
- * (Yes, this sucks, but that's the way libnet works, and
- * I was too lazy to re-invent the wheel.
- * Returns 0 on sucess, -1 on error
- */
- int
- fix_checksums(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr, ipv4_hdr_t *ip_hdr)
- {
- int ret1 = 0, ret2 = 0;
- assert(tcpedit);
- assert(pkthdr);
- assert(ip_hdr);
-
- /* calc the L4 checksum if we have the whole packet && not a frag or first frag */
- if (pkthdr->caplen == pkthdr->len && (htons(ip_hdr->ip_off) & IP_OFFMASK) == 0) {
- ret1 = do_checksum(tcpedit, (u_char *) ip_hdr,
- ip_hdr->ip_p, ntohs(ip_hdr->ip_len) - (ip_hdr->ip_hl << 2));
- if (ret1 < 0)
- return TCPEDIT_ERROR;
- }
-
- /* calc IP checksum */
- ret2 = do_checksum(tcpedit, (u_char *) ip_hdr, IPPROTO_IP, ntohs(ip_hdr->ip_len));
- if (ret2 < 0)
- return TCPEDIT_ERROR;
- /* what do we return? */
- if (ret1 == TCPEDIT_WARN || ret2 == TCPEDIT_WARN)
- return TCPEDIT_WARN;
-
- return TCPEDIT_OK;
- }
- /**
- * returns a new 32bit integer which is the randomized IP
- * based upon the user specified seed
- */
- static u_int32_t
- randomize_ipv4_addr(tcpedit_t *tcpedit, u_int32_t ip)
- {
- assert(tcpedit);
-
- /* don't rewrite broadcast addresses */
- if (tcpedit->skip_broadcast && !is_unicast_ipv4(tcpedit, ip))
- return ip;
-
- return ((ip ^ htonl(tcpedit->seed)) - (ip & htonl(tcpedit->seed)));
- }
- /**
- * randomizes the source and destination IP addresses based on a
- * pseudo-random number which is generated via the seed.
- * return 1 since we changed one or more IP addresses
- */
- int
- randomize_ipv4(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
- u_char *pktdata, ipv4_hdr_t *ip_hdr)
- {
- #ifdef DEBUG
- char srcip[16], dstip[16];
- #endif
- assert(tcpedit);
- assert(pkthdr);
- assert(pktdata);
- assert(ip_hdr);
- #ifdef DEBUG
- strlcpy(srcip, get_addr2name4(ip_hdr->ip_src.s_addr,
- RESOLVE), 16);
- strlcpy(dstip, get_addr2name4(ip_hdr->ip_dst.s_addr,
- RESOLVE), 16);
- #endif
- /* randomize IP addresses based on the value of random */
- dbgx(1, "Old Src IP: %s\tOld Dst IP: %s", srcip, dstip);
- /* don't rewrite broadcast addresses */
- if ((tcpedit->skip_broadcast && is_unicast_ipv4(tcpedit, (u_int32_t)ip_hdr->ip_dst.s_addr))
- || !tcpedit->skip_broadcast) {
- ip_hdr->ip_dst.s_addr = randomize_ipv4_addr(tcpedit, ip_hdr->ip_dst.s_addr);
- }
-
- if ((tcpedit->skip_broadcast && is_unicast_ipv4(tcpedit, (u_int32_t)ip_hdr->ip_src.s_addr))
- || !tcpedit->skip_broadcast) {
- ip_hdr->ip_src.s_addr = randomize_ipv4_addr(tcpedit, ip_hdr->ip_src.s_addr);
- }
- #ifdef DEBUG
- strlcpy(srcip, get_addr2name4(ip_hdr->ip_src.s_addr,
- RESOLVE), 16);
- strlcpy(dstip, get_addr2name4(ip_hdr->ip_dst.s_addr,
- RESOLVE), 16);
- #endif
- dbgx(1, "New Src IP: %s\tNew Dst IP: %s\n", srcip, dstip);
- return(1);
- }
- /**
- * this code will untruncate a packet via padding it with null
- * or resetting the actual IPv4 packet len to the snaplen - L2 header.
- * return 0 if no change, 1 if change, -1 on error.
- */
- int
- untrunc_packet(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
- u_char *pktdata, ipv4_hdr_t *ip_hdr)
- {
- int l2len;
- assert(tcpedit);
- assert(pkthdr);
- assert(pktdata);
- /* if actual len == cap len or there's no IP header, don't do anything */
- if ((pkthdr->caplen == pkthdr->len) || (ip_hdr == NULL)) {
- /* unless we're in MTU truncate mode */
- if (! tcpedit->mtu_truncate)
- return(0);
- }
-
- if ((l2len = layer2len(tcpedit)) < 0) {
- tcpedit_seterr(tcpedit, "Non-sensical layer 2 length: %d", l2len);
- return -1;
- }
- /* Pad packet or truncate it */
- if (tcpedit->fixlen == TCPEDIT_FIXLEN_PAD) {
- /*
- * this should be an unnecessary check
- * but I've gotten a report that sometimes the caplen > len
- * which seems like a corrupted pcap
- */
- if (pkthdr->len > pkthdr->caplen) {
- memset(pktdata + pkthdr->caplen, '\0', pkthdr->len - pkthdr->caplen);
- pkthdr->caplen = pkthdr->len;
- } else if (pkthdr->len < pkthdr->caplen) {
- /* i guess this is necessary if we've got a bogus pcap */
- //ip_hdr->ip_len = htons(pkthdr->caplen - l2len);
- tcpedit_seterr(tcpedit, "%s", "WTF? Why is your packet larger then the capture len?");
- return -1;
- }
- }
- else if (tcpedit->fixlen == TCPEDIT_FIXLEN_TRUNC) {
- if (pkthdr->len != pkthdr->caplen)
- ip_hdr->ip_len = htons(pkthdr->caplen - l2len);
- pkthdr->len = pkthdr->caplen;
- }
- else if (tcpedit->mtu_truncate) {
- if (pkthdr->len > (tcpedit->mtu + l2len)) {
- /* first truncate the packet */
- pkthdr->len = pkthdr->caplen = l2len + tcpedit->mtu;
-
- /* if ip_hdr exists, update the length */
- if (ip_hdr != NULL) {
- ip_hdr->ip_len = htons(tcpedit->mtu);
- } else {
- /* for non-IP frames, don't try to fix checksums */
- return 0;
- }
- }
- }
- else {
- tcpedit_seterr(tcpedit, "Invalid fixlen value: 0x%x", tcpedit->fixlen);
- return -1;
- }
- return(1);
- }
- /**
- * Extracts the layer 7 data from the packet for TCP, UDP, ICMP
- * returns the number of bytes and a pointer to the layer 7 data.
- * Returns 0 for no data
- */
- int
- extract_data(tcpedit_t *tcpedit, const u_char *pktdata, int caplen,
- char *l7data[])
- {
- int datalen = 0;
- ipv4_hdr_t *ip_hdr = NULL;
- tcp_hdr_t *tcp_hdr = NULL;
- udp_hdr_t *udp_hdr = NULL;
- u_char ipbuff[MAXPACKET];
- u_char *dataptr = NULL;
-
- assert(tcpedit);
- assert(pktdata);
- assert(l7data);
- /* grab our IPv4 header */
- dataptr = ipbuff;
- if ((ip_hdr = (ipv4_hdr_t*)get_ipv4(pktdata, caplen,
- tcpedit->runtime.dlt1, &dataptr)) == NULL)
- return 0;
- /* figure out the actual datalen which might be < the caplen
- * due to ethernet padding
- */
- if (caplen > ntohs(ip_hdr->ip_len)) {
- datalen = ntohs(ip_hdr->ip_len);
- } else {
- datalen = caplen - tcpedit->dlt_ctx->l2len;
- }
- /* update the datlen to not include the IP header len */
- datalen -= ip_hdr->ip_hl << 2;
- dataptr += ip_hdr->ip_hl << 2;
- if (datalen <= 0)
- goto nodata;
- /* TCP ? */
- if (ip_hdr->ip_p == IPPROTO_TCP) {
- tcp_hdr = (tcp_hdr_t *) get_layer4(ip_hdr);
- datalen -= tcp_hdr->th_off << 2;
- if (datalen <= 0)
- goto nodata;
- dataptr += tcp_hdr->th_off << 2;
- }
- /* UDP ? */
- else if (ip_hdr->ip_p == IPPROTO_UDP) {
- udp_hdr = (udp_hdr_t *) get_layer4(ip_hdr);
- datalen -= TCPR_UDP_H;
- if (datalen <= 0)
- goto nodata;
- dataptr += TCPR_UDP_H;
- }
- /* ICMP ? just ignore it for now */
- else if (ip_hdr->ip_p == IPPROTO_ICMP) {
- dbg(2, "Ignoring any possible data in ICMP packet");
- goto nodata;
- }
- /* unknown proto, just dump everything past the IP header */
- else {
- dbg(2, "Unknown protocol, dumping everything past the IP header");
- dataptr = (u_char *)ip_hdr;
- }
- dbgx(2, "packet had %d bytes of layer 7 data", datalen);
- memcpy(l7data, dataptr, datalen);
- return datalen;
- nodata:
- dbg(2, "packet has no data, skipping...");
- return 0;
- }
- /**
- * rewrites an IPv4 packet's TTL based on the rules
- * return 0 if no change, 1 if changed
- */
- int
- rewrite_ipv4_ttl(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr)
- {
- assert(tcpedit);
- /* make sure there's something to edit */
- if (ip_hdr == NULL || tcpedit->ttl_mode == TCPEDIT_TTL_OFF)
- return(0);
-
- switch(tcpedit->ttl_mode) {
- case TCPEDIT_TTL_SET:
- if (ip_hdr->ip_ttl == tcpedit->ttl_value)
- return(0); /* no change required */
- ip_hdr->ip_ttl = tcpedit->ttl_value;
- break;
- case TCPEDIT_TTL_ADD:
- if (((int)ip_hdr->ip_ttl + tcpedit->ttl_value) > 255) {
- ip_hdr->ip_ttl = 255;
- } else {
- ip_hdr->ip_ttl += tcpedit->ttl_value;
- }
- break;
- case TCPEDIT_TTL_SUB:
- if (ip_hdr->ip_ttl <= tcpedit->ttl_value) {
- ip_hdr->ip_ttl = 1;
- } else {
- ip_hdr->ip_ttl -= tcpedit->ttl_value;
- }
- break;
- default:
- errx(1, "invalid ttl_mode: %d", tcpedit->ttl_mode);
- }
- return(1);
- }
- /**
- * takes a CIDR notation netblock and uses that to "remap" given IP
- * onto that netblock. ie: 10.0.0.0/8 and 192.168.55.123 -> 10.168.55.123
- * while 10.150.9.0/24 and 192.168.55.123 -> 10.150.9.123
- */
- static u_int32_t
- remap_ipv4(tcpedit_t *tcpedit, tcpr_cidr_t *cidr, const u_int32_t original)
- {
- u_int32_t ipaddr = 0, network = 0, mask = 0, result = 0;
- assert(tcpedit);
- assert(cidr);
-
- /* don't rewrite broadcast addresses */
- if (tcpedit->skip_broadcast && !is_unicast_ipv4(tcpedit, original))
- return original;
- mask = 0xffffffff; /* turn on all the bits */
- /* shift over by correct # of bits */
- mask = mask << (32 - cidr->masklen);
- /* apply the mask to the network */
- network = htonl(cidr->network) & mask;
- /* apply the reverse of the mask to the IP */
- mask = mask ^ 0xffffffff;
- ipaddr = ntohl(original) & mask;
- /* merge the network portion and ip portions */
- result = network ^ ipaddr;
-
- /* return the result in network byte order */
- return(htonl(result));
- }
- /**
- * rewrite IP address (layer3)
- * uses -N to rewrite (map) one subnet onto another subnet
- * also support --srcipmap and --dstipmap
- * return 0 if no change, 1 or 2 if changed
- */
- int
- rewrite_ipv4l3(tcpedit_t *tcpedit, ipv4_hdr_t *ip_hdr, tcpr_dir_t direction)
- {
- tcpr_cidrmap_t *cidrmap1 = NULL, *cidrmap2 = NULL;
- int didsrc = 0, diddst = 0, loop = 1;
- assert(tcpedit);
- assert(ip_hdr);
- /* first check the src/dst IP maps */
- if (tcpedit->srcipmap != NULL) {
- if (ip_in_cidr(tcpedit->srcipmap->from, ip_hdr->ip_src.s_addr)) {
- ip_hdr->ip_src.s_addr = remap_ipv4(tcpedit, tcpedit->srcipmap->to, ip_hdr->ip_src.s_addr);
- dbgx(2, "Remapped src addr to: %s", get_addr2name4(ip_hdr->ip_src.s_addr, RESOLVE));
- }
- }
- if (tcpedit->dstipmap != NULL) {
- if (ip_in_cidr(tcpedit->dstipmap->from, ip_hdr->ip_dst.s_addr)) {
- ip_hdr->ip_dst.s_addr = remap_ipv4(tcpedit, tcpedit->dstipmap->to, ip_hdr->ip_dst.s_addr);
- dbgx(2, "Remapped src addr to: %s", get_addr2name4(ip_hdr->ip_dst.s_addr, RESOLVE));
- }
- }
- /* anything else to rewrite? */
- if (tcpedit->cidrmap1 == NULL)
- return(0);
- /* don't play with the main pointers */
- if (direction == TCPR_DIR_C2S) {
- cidrmap1 = tcpedit->cidrmap1;
- cidrmap2 = tcpedit->cidrmap2;
- } else {
- cidrmap1 = tcpedit->cidrmap2;
- cidrmap2 = tcpedit->cidrmap1;
- }
-
- /* loop through the cidrmap to rewrite */
- do {
- if ((! diddst) && ip_in_cidr(cidrmap2->from, ip_hdr->ip_dst.s_addr)) {
- ip_hdr->ip_dst.s_addr = remap_ipv4(tcpedit, cidrmap2->to, ip_hdr->ip_dst.s_addr);
- dbgx(2, "Remapped dst addr to: %s", get_addr2name4(ip_hdr->ip_dst.s_addr, RESOLVE));
- diddst = 1;
- }
- if ((! didsrc) && ip_in_cidr(cidrmap1->from, ip_hdr->ip_src.s_addr)) {
- ip_hdr->ip_src.s_addr = remap_ipv4(tcpedit, cidrmap1->to, ip_hdr->ip_src.s_addr);
- dbgx(2, "Remapped src addr to: %s", get_addr2name4(ip_hdr->ip_src.s_addr, RESOLVE));
- didsrc = 1;
- }
- /*
- * loop while we haven't modified both src/dst AND
- * at least one of the cidr maps have a next pointer
- */
- if ((! (diddst && didsrc)) &&
- (! ((cidrmap1->next == NULL) && (cidrmap2->next == NULL)))) {
- /* increment our ptr's if possible */
- if (cidrmap1->next != NULL)
- cidrmap1 = cidrmap1->next;
- if (cidrmap2->next != NULL)
- cidrmap2 = cidrmap2->next;
- } else {
- loop = 0;
- }
- /* Later on we should support various IP protocols which embed
- * the IP address in the application layer. Things like
- * DNS and FTP.
- */
- } while (loop);
- /* return how many changes we made */
- return (diddst + didsrc);
- }
- /**
- * Randomize the IP addresses in an ARP packet based on the user seed
- * return 0 if no change, or 1 for a change
- */
- int
- randomize_iparp(tcpedit_t *tcpedit, struct pcap_pkthdr *pkthdr,
- u_char *pktdata, int datalink)
- {
- arp_hdr_t *arp_hdr = NULL;
- int l2len = 0;
- u_int32_t *ip, tempip;
- u_char *add_hdr;
- assert(tcpedit);
- assert(pkthdr);
- assert(pktdata);
- l2len = get_l2len(pktdata, pkthdr->caplen, datalink);
- arp_hdr = (arp_hdr_t *)(pktdata + l2len);
- /*
- * only rewrite IP addresses from REPLY/REQUEST's
- */
- if ((ntohs(arp_hdr->ar_pro) == ETHERTYPE_IP) &&
- ((ntohs(arp_hdr->ar_op) == ARPOP_REQUEST) ||
- (ntohs(arp_hdr->ar_op) == ARPOP_REPLY))) {
- /* jump to the addresses */
- add_hdr = (u_char *)arp_hdr;
- add_hdr += sizeof(arp_hdr_t) + arp_hdr->ar_hln;
- ip = (u_int32_t *)add_hdr;
- tempip = randomize_ipv4_addr(tcpedit, *ip);
- memcpy(ip, &tempip, sizeof(u_int32_t));
- add_hdr += arp_hdr->ar_pln + arp_hdr->ar_hln;
- ip = (u_int32_t *)add_hdr;
- tempip = randomize_ipv4_addr(tcpedit, *ip);
- memcpy(ip, &tempip, sizeof(u_int32_t));
- }
- return 1; /* yes we changed the packet */
- }
- /**
- * rewrite IP address (arp)
- * uses -a to rewrite (map) one subnet onto another subnet
- * pointer must point to the WHOLE and CONTIGOUS memory buffer
- * because the arp_hdr_t doesn't have the space for the IP/MAC
- * addresses
- * return 0 if no change, 1 or 2 if changed
- */
- int
- rewrite_iparp(tcpedit_t *tcpedit, arp_hdr_t *arp_hdr, int cache_mode)
- {
- u_char *add_hdr = NULL;
- u_int32_t *ip1 = NULL, *ip2 = NULL;
- u_int32_t newip = 0;
- tcpr_cidrmap_t *cidrmap1 = NULL, *cidrmap2 = NULL;
- int didsrc = 0, diddst = 0, loop = 1;
- #ifdef FORCE_ALIGN
- u_int32_t iptemp;
- #endif
- assert(tcpedit);
- assert(arp_hdr);
- /* figure out what mapping to use */
- if (cache_mode == TCPR_DIR_C2S) {
- cidrmap1 = tcpedit->cidrmap1;
- cidrmap2 = tcpedit->cidrmap2;
- } else if (cache_mode == TCPR_DIR_S2C) {
- cidrmap1 = tcpedit->cidrmap2;
- cidrmap2 = tcpedit->cidrmap1;
- }
- /* anything to rewrite? */
- if (cidrmap1 == NULL || cidrmap2 == NULL)
- return(0);
- /*
- * must be IPv4 and request or reply
- * Do other op codes use the same subheader stub?
- * If so we won't need to check the op code.
- */
- if ((ntohs(arp_hdr->ar_pro) == ETHERTYPE_IP) &&
- ((ntohs(arp_hdr->ar_op) == ARPOP_REQUEST) ||
- (ntohs(arp_hdr->ar_op) == ARPOP_REPLY)))
- {
- /* jump to the addresses */
- add_hdr = (u_char *)arp_hdr;
- add_hdr += sizeof(arp_hdr_t) + arp_hdr->ar_hln;
- ip1 = (u_int32_t *)add_hdr;
- add_hdr += arp_hdr->ar_pln + arp_hdr->ar_hln;
- #ifdef FORCE_ALIGN
- /* copy IP2 to a temporary buffer for processing */
- memcpy(&iptemp, add_hdr, sizeof(u_int32_t));
- ip2 = &iptemp;
- #else
- ip2 = (u_int32_t *)add_hdr;
- #endif
-
- /* loop through the cidrmap to rewrite */
- do {
- /* arp request ? */
- if (ntohs(arp_hdr->ar_op) == ARPOP_REQUEST) {
- if ((!diddst) && ip_in_cidr(cidrmap2->from, *ip1)) {
- newip = remap_ipv4(tcpedit, cidrmap2->to, *ip1);
- memcpy(ip1, &newip, 4);
- diddst = 1;
- }
- if ((!didsrc) && ip_in_cidr(cidrmap1->from, *ip2)) {
- newip = remap_ipv4(tcpedit, cidrmap1->to, *ip2);
- memcpy(ip2, &newip, 4);
- didsrc = 1;
- }
- }
- /* else it's an arp reply */
- else {
- if ((!diddst) && ip_in_cidr(cidrmap2->from, *ip2)) {
- newip = remap_ipv4(tcpedit, cidrmap2->to, *ip2);
- memcpy(ip2, &newip, 4);
- diddst = 1;
- }
- if ((!didsrc) && ip_in_cidr(cidrmap1->from, *ip1)) {
- newip = remap_ipv4(tcpedit, cidrmap1->to, *ip1);
- memcpy(ip1, &newip, 4);
- didsrc = 1;
- }
- }
- #ifdef FORCE_ALIGN
- /* copy temporary IP to IP2 location in buffer */
- memcpy(add_hdr, &iptemp, sizeof(u_int32_t));
- #endif
- /*
- * loop while we haven't modified both src/dst AND
- * at least one of the cidr maps have a next pointer
- */
- if ((! (diddst && didsrc)) &&
- (! ((cidrmap1->next == NULL) && (cidrmap2->next == NULL)))) {
-
- /* increment our ptr's if possible */
- if (cidrmap1->next != NULL)
- cidrmap1 = cidrmap1->next;
-
- if (cidrmap2->next != NULL)
- cidrmap2 = cidrmap2->next;
-
- } else {
- loop = 0;
- }
- } while (loop);
-
- } else {
- warn("ARP packet isn't for IPv4! Can't rewrite IP's");
- }
- return(didsrc + diddst);
- }
- /**
- * returns 1 if the IP address is a unicast address, otherwise, returns 0
- * for broadcast/multicast addresses. Returns -1 on error
- */
- static int
- is_unicast_ipv4(tcpedit_t *tcpedit, u_int32_t ip)
- {
- assert(tcpedit);
-
- /* multicast/broadcast is 224.0.0.0 or greater */
- if (ip > 3758096384)
- return 0;
-
- return 1;
- }
- /*
- Local Variables:
- mode:c
- indent-tabs-mode:nil
- c-basic-offset:4
- End:
- */
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