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/*
* This program manages IPv6 address with OCF Resource Agent standard.
*
* Author: Huang Zhen <zhenh@cn.ibm.com>
* Copyright (c) 2004 International Business Machines
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <IPv6addr.h>
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h> /* for inet_pton */
#include <net/if.h> /* for if_nametoindex */
#include <sys/ioctl.h>
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
/* Send an unsolicited advertisement packet
* Please refer to rfc4861 / rfc3542
*/
int
send_ua(struct in6_addr* src_ip, char* if_name)
{
int status = -1;
int fd;
int ifindex;
int hop;
struct ifreq ifr;
u_int8_t *payload = NULL;
int payload_size;
struct nd_neighbor_advert *na;
struct nd_opt_hdr *opt;
struct sockaddr_in6 src_sin6;
struct sockaddr_in6 dst_sin6;
if ((fd = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) == -1) {
printf("ERROR: socket(IPPROTO_ICMPV6) failed: %s",
strerror(errno));
return status;
}
/* set the outgoing interface */
ifindex = if_nametoindex(if_name);
if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_IF,
&ifindex, sizeof(ifindex)) < 0) {
printf("ERROR: setsockopt(IPV6_MULTICAST_IF) failed: %s",
strerror(errno));
goto err;
}
/* set the hop limit */
hop = 255; /* 255 is required. see rfc4861 7.1.2 */
if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
&hop, sizeof(hop)) < 0) {
printf("ERROR: setsockopt(IPV6_MULTICAST_HOPS) failed: %s",
strerror(errno));
goto err;
}
/* set the source address */
memset(&src_sin6, 0, sizeof(src_sin6));
src_sin6.sin6_family = AF_INET6;
src_sin6.sin6_addr = *src_ip;
src_sin6.sin6_port = 0;
if (IN6_IS_ADDR_LINKLOCAL(&src_sin6.sin6_addr) ||
IN6_IS_ADDR_MC_LINKLOCAL(&src_sin6.sin6_addr)) {
src_sin6.sin6_scope_id = ifindex;
}
if (bind(fd, (struct sockaddr *)&src_sin6, sizeof(src_sin6)) < 0) {
printf("ERROR: bind() failed: %s", strerror(errno));
goto err;
}
/* get the hardware address */
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, if_name, sizeof(ifr.ifr_name) - 1);
if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
printf("ERROR: ioctl(SIOCGIFHWADDR) failed: %s", strerror(errno));
goto err;
}
/* build a neighbor advertisement message */
payload_size = sizeof(struct nd_neighbor_advert)
+ sizeof(struct nd_opt_hdr) + HWADDR_LEN;
payload = memalign(sysconf(_SC_PAGESIZE), payload_size);
if (!payload) {
printf("ERROR: malloc for payload failed");
goto err;
}
memset(payload, 0, payload_size);
/* Ugly typecast from ia64 hell! */
na = (struct nd_neighbor_advert *)((void *)payload);
na->nd_na_type = ND_NEIGHBOR_ADVERT;
na->nd_na_code = 0;
na->nd_na_cksum = 0; /* calculated by kernel */
na->nd_na_flags_reserved = ND_NA_FLAG_OVERRIDE;
na->nd_na_target = *src_ip;
/* options field; set the target link-layer address */
opt = (struct nd_opt_hdr *)(payload + sizeof(struct nd_neighbor_advert));
opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
opt->nd_opt_len = 1; /* The length of the option in units of 8 octets */
memcpy(payload + sizeof(struct nd_neighbor_advert)
+ sizeof(struct nd_opt_hdr),
&ifr.ifr_hwaddr.sa_data, HWADDR_LEN);
/* sending an unsolicited neighbor advertisement to all */
memset(&dst_sin6, 0, sizeof(dst_sin6));
dst_sin6.sin6_family = AF_INET6;
inet_pton(AF_INET6, BCAST_ADDR, &dst_sin6.sin6_addr); /* should not fail */
if (sendto(fd, payload, payload_size, 0,
(struct sockaddr *)&dst_sin6, sizeof(dst_sin6))
!= payload_size) {
printf("ERROR: sendto(%s) failed: %s",
if_name, strerror(errno));
goto err;
}
status = 0;
err:
close(fd);
free(payload);
return status;
}
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