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/*
* $Id: recv.c,v 1.12 2010/01/28 13:34:26 psavola Exp $
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
* Lars Fenneberg <lf@elemental.net>
*
* This software is Copyright 1996,1997 by the above mentioned author(s),
* All Rights Reserved.
*
* The license which is distributed with this software in the file COPYRIGHT
* applies to this software. If your distribution is missing this file, you
* may request it from <pekkas@netcore.fi>.
*
*/
#include <config.h>
#include <includes.h>
#include <radvd.h>
int
recv_rs_ra(int sock, unsigned char *msg, struct sockaddr_in6 *addr,
struct in6_pktinfo **pkt_info, int *hoplimit)
{
struct msghdr mhdr;
struct cmsghdr *cmsg;
struct iovec iov;
static unsigned char *chdr = NULL;
static unsigned int chdrlen = 0;
int len;
fd_set rfds;
if( ! chdr )
{
chdrlen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
CMSG_SPACE(sizeof(int));
if ((chdr = malloc(chdrlen)) == NULL) {
flog(LOG_ERR, "recv_rs_ra: malloc: %s", strerror(errno));
return -1;
}
}
FD_ZERO( &rfds );
FD_SET( sock, &rfds );
if( select( sock+1, &rfds, NULL, NULL, NULL ) < 0 )
{
if (errno != EINTR)
flog(LOG_ERR, "select: %s", strerror(errno));
return -1;
}
iov.iov_len = MSG_SIZE_RECV;
iov.iov_base = (caddr_t) msg;
memset(&mhdr, 0, sizeof(mhdr));
mhdr.msg_name = (caddr_t)addr;
mhdr.msg_namelen = sizeof(*addr);
mhdr.msg_iov = &iov;
mhdr.msg_iovlen = 1;
mhdr.msg_control = (void *)chdr;
mhdr.msg_controllen = chdrlen;
len = recvmsg(sock, &mhdr, 0);
if (len < 0)
{
if (errno != EINTR)
flog(LOG_ERR, "recvmsg: %s", strerror(errno));
return len;
}
*hoplimit = 255;
for (cmsg = CMSG_FIRSTHDR(&mhdr); cmsg != NULL; cmsg = CMSG_NXTHDR(&mhdr, cmsg))
{
if (cmsg->cmsg_level != IPPROTO_IPV6)
continue;
switch(cmsg->cmsg_type)
{
#ifdef IPV6_HOPLIMIT
case IPV6_HOPLIMIT:
if ((cmsg->cmsg_len == CMSG_LEN(sizeof(int))) &&
(*(int *)CMSG_DATA(cmsg) >= 0) &&
(*(int *)CMSG_DATA(cmsg) < 256))
{
*hoplimit = *(int *)CMSG_DATA(cmsg);
}
else
{
flog(LOG_ERR, "received a bogus IPV6_HOPLIMIT from the kernel! len=%d, data=%d",
cmsg->cmsg_len, *(int *)CMSG_DATA(cmsg));
return (-1);
}
break;
#endif /* IPV6_HOPLIMIT */
case IPV6_PKTINFO:
if ((cmsg->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) &&
((struct in6_pktinfo *)CMSG_DATA(cmsg))->ipi6_ifindex)
{
*pkt_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
}
else
{
flog(LOG_ERR, "received a bogus IPV6_PKTINFO from the kernel! len=%d, index=%d",
cmsg->cmsg_len, ((struct in6_pktinfo *)CMSG_DATA(cmsg))->ipi6_ifindex);
return (-1);
}
break;
}
}
dlog(LOG_DEBUG, 4, "recvmsg len=%d", len);
return len;
}
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