diff options
Diffstat (limited to 'src/libsystemd-network/src/icmp6-util.c')
| -rw-r--r-- | src/libsystemd-network/src/icmp6-util.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/libsystemd-network/src/icmp6-util.c b/src/libsystemd-network/src/icmp6-util.c new file mode 100644 index 0000000000..4280d32e3d --- /dev/null +++ b/src/libsystemd-network/src/icmp6-util.c @@ -0,0 +1,142 @@ +/*** + This file is part of systemd. + + Copyright (C) 2014 Intel Corporation. All rights reserved. + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <net/if.h> +#include <netinet/icmp6.h> +#include <netinet/in.h> +#include <netinet/ip6.h> +#include <stdio.h> +#include <string.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <unistd.h> + +#include <linux/if_packet.h> + +#include "systemd-basic/fd-util.h" +#include "systemd-basic/socket-util.h" +#include "systemd-network/icmp6-util.h" + +#define IN6ADDR_ALL_ROUTERS_MULTICAST_INIT \ + { { { 0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02 } } } + +#define IN6ADDR_ALL_NODES_MULTICAST_INIT \ + { { { 0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } } + +int icmp6_bind_router_solicitation(int index) { + struct icmp6_filter filter = { }; + struct ipv6_mreq mreq = { + .ipv6mr_multiaddr = IN6ADDR_ALL_NODES_MULTICAST_INIT, + .ipv6mr_interface = index, + }; + _cleanup_close_ int s = -1; + char ifname[IF_NAMESIZE] = ""; + static const int zero = 0, one = 1, hops = 255; + int r; + + s = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, IPPROTO_ICMPV6); + if (s < 0) + return -errno; + + ICMP6_FILTER_SETBLOCKALL(&filter); + ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filter); + r = setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filter, sizeof(filter)); + if (r < 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(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index)); + if (r < 0) + return -errno; + + r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &zero, sizeof(zero)); + if (r < 0) + return -errno; + + r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hops, sizeof(hops)); + if (r < 0) + return -errno; + + r = setsockopt(s, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)); + if (r < 0) + return -errno; + + r = setsockopt(s, SOL_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one)); + if (r < 0) + return -errno; + + r = setsockopt(s, SOL_SOCKET, SO_TIMESTAMP, &one, sizeof(one)); + if (r < 0) + return -errno; + + if (if_indextoname(index, ifname) == 0) + return -errno; + + r = setsockopt(s, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)); + if (r < 0) + return -errno; + + r = s; + s = -1; + return r; +} + +int icmp6_send_router_solicitation(int s, const struct ether_addr *ether_addr) { + struct sockaddr_in6 dst = { + .sin6_family = AF_INET6, + .sin6_addr = IN6ADDR_ALL_ROUTERS_MULTICAST_INIT, + }; + struct { + struct nd_router_solicit rs; + struct nd_opt_hdr rs_opt; + struct ether_addr rs_opt_mac; + } _packed_ rs = { + .rs.nd_rs_type = ND_ROUTER_SOLICIT, + .rs_opt.nd_opt_type = ND_OPT_SOURCE_LINKADDR, + .rs_opt.nd_opt_len = 1, + }; + struct iovec iov = { + .iov_base = &rs, + .iov_len = sizeof(rs), + }; + struct msghdr msg = { + .msg_name = &dst, + .msg_namelen = sizeof(dst), + .msg_iov = &iov, + .msg_iovlen = 1, + }; + int r; + + assert(s >= 0); + assert(ether_addr); + + rs.rs_opt_mac = *ether_addr; + + r = sendmsg(s, &msg, 0); + if (r < 0) + return -errno; + + return 0; +} |