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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/***
Copyright © 2014 Intel Corporation. All rights reserved.
***/
/* Make sure the net/if.h header is included before any linux/ one */
#include <net/if.h>
#include <errno.h>
#include <linux/if_packet.h>
#include <netinet/icmp6.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include "fd-util.h"
#include "icmp6-util.h"
#include "in-addr-util.h"
#include "iovec-util.h"
#include "network-common.h"
#include "socket-util.h"
int icmp6_bind(int ifindex, bool is_router) {
struct icmp6_filter filter = {};
struct ipv6_mreq mreq;
_cleanup_close_ int s = -EBADF;
int r;
assert(ifindex > 0);
ICMP6_FILTER_SETBLOCKALL(&filter);
if (is_router) {
mreq = (struct ipv6_mreq) {
.ipv6mr_multiaddr = IN6_ADDR_ALL_ROUTERS_MULTICAST,
.ipv6mr_interface = ifindex,
};
ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filter);
} else {
mreq = (struct ipv6_mreq) {
.ipv6mr_multiaddr = IN6_ADDR_ALL_NODES_MULTICAST,
.ipv6mr_interface = ifindex,
};
ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filter);
ICMP6_FILTER_SETPASS(ND_NEIGHBOR_ADVERT, &filter);
ICMP6_FILTER_SETPASS(ND_REDIRECT, &filter);
}
s = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, IPPROTO_ICMPV6);
if (s < 0)
return -errno;
if (setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filter, sizeof(filter)) < 0)
return -errno;
if (setsockopt(s, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
return -errno;
/* RFC 3315, section 6.7, bullet point 2 may indicate that an IPV6_PKTINFO socket option also applies
* for ICMPv6 multicast. Empirical experiments indicates otherwise and therefore an IPV6_MULTICAST_IF
* socket option is used here instead. */
r = setsockopt_int(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, ifindex);
if (r < 0)
return r;
r = setsockopt_int(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, false);
if (r < 0)
return r;
r = setsockopt_int(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, 255);
if (r < 0)
return r;
r = setsockopt_int(s, IPPROTO_IPV6, IPV6_UNICAST_HOPS, 255);
if (r < 0)
return r;
r = setsockopt_int(s, SOL_IPV6, IPV6_RECVHOPLIMIT, true);
if (r < 0)
return r;
r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
if (r < 0)
return r;
r = socket_bind_to_ifindex(s, ifindex);
if (r < 0)
return r;
return TAKE_FD(s);
}
int icmp6_send(int fd, const struct in6_addr *dst, const struct iovec *iov, size_t n_iov) {
struct sockaddr_in6 sa = {
.sin6_family = AF_INET6,
.sin6_addr = *ASSERT_PTR(dst),
};
struct msghdr msg = {
.msg_name = &sa,
.msg_namelen = sizeof(struct sockaddr_in6),
.msg_iov = (struct iovec*) iov,
.msg_iovlen = n_iov,
};
assert(fd >= 0);
if (sendmsg(fd, &msg, 0) < 0)
return -errno;
return 0;
}
int icmp6_receive(
int fd,
void *buffer,
size_t size,
struct in6_addr *ret_sender,
triple_timestamp *ret_timestamp) {
/* This needs to be initialized with zero. See #20741. */
CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(int)) + /* ttl */
CMSG_SPACE_TIMEVAL) control = {};
struct iovec iov = {};
union sockaddr_union sa = {};
struct msghdr msg = {
.msg_name = &sa.sa,
.msg_namelen = sizeof(sa),
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = &control,
.msg_controllen = sizeof(control),
};
ssize_t len;
iov = IOVEC_MAKE(buffer, size);
len = recvmsg_safe(fd, &msg, MSG_DONTWAIT);
if (len < 0)
return (int) len;
if ((size_t) len != size)
return -EINVAL;
if (msg.msg_namelen != sizeof(struct sockaddr_in6) || sa.in6.sin6_family != AF_INET6)
return -EPFNOSUPPORT;
if (!in6_addr_is_link_local(&sa.in6.sin6_addr) && !in6_addr_is_null(&sa.in6.sin6_addr))
return -EADDRNOTAVAIL;
assert(!(msg.msg_flags & MSG_TRUNC));
int *hops = CMSG_FIND_DATA(&msg, SOL_IPV6, IPV6_HOPLIMIT, int);
if (hops && *hops != 255)
return -EMULTIHOP;
if (ret_timestamp)
triple_timestamp_from_cmsg(ret_timestamp, &msg);
if (ret_sender)
*ret_sender = sa.in6.sin6_addr;
return 0;
}
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