/* Kernel communication using netlink interface.
* Copyright (C) 1999 Kunihiro Ishiguro
*
* This file is part of GNU Zebra.
*
* GNU Zebra 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, or (at your option) any
* later version.
*
* GNU Zebra 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; see the file COPYING; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <zebra.h>
#ifdef HAVE_NETLINK
#include "linklist.h"
#include "if.h"
#include "log.h"
#include "prefix.h"
#include "connected.h"
#include "table.h"
#include "memory.h"
#include "zebra_memory.h"
#include "rib.h"
#include "thread.h"
#include "privs.h"
#include "nexthop.h"
#include "vrf.h"
#include "mpls.h"
#include "lib_errors.h"
//#include "zebra/zserv.h"
#include "zebra/zebra_router.h"
#include "zebra/zebra_ns.h"
#include "zebra/zebra_vrf.h"
#include "zebra/rt.h"
#include "zebra/debug.h"
#include "zebra/kernel_netlink.h"
#include "zebra/rt_netlink.h"
#include "zebra/if_netlink.h"
#include "zebra/rule_netlink.h"
#include "zebra/zebra_errors.h"
#ifndef SO_RCVBUFFORCE
#define SO_RCVBUFFORCE (33)
#endif
/* Hack for GNU libc version 2. */
#ifndef MSG_TRUNC
#define MSG_TRUNC 0x20
#endif /* MSG_TRUNC */
#ifndef NLMSG_TAIL
#define NLMSG_TAIL(nmsg) \
((struct rtattr *)(((uint8_t *)(nmsg)) \
+ NLMSG_ALIGN((nmsg)->nlmsg_len)))
#endif
#ifndef RTA_TAIL
#define RTA_TAIL(rta) \
((struct rtattr *)(((uint8_t *)(rta)) + RTA_ALIGN((rta)->rta_len)))
#endif
#ifndef RTNL_FAMILY_IP6MR
#define RTNL_FAMILY_IP6MR 129
#endif
#ifndef RTPROT_MROUTED
#define RTPROT_MROUTED 17
#endif
#define NL_DEFAULT_BATCH_BUFSIZE (16 * NL_PKT_BUF_SIZE)
/*
* We limit the batch's size to a number smaller than the length of the
* underlying buffer since the last message that wouldn't fit the batch would go
* over the upper boundary and then it would have to be encoded again into a new
* buffer. If the difference between the limit and the length of the buffer is
* big enough (bigger than the biggest Netlink message) then this situation
* won't occur.
*/
#define NL_DEFAULT_BATCH_SEND_THRESHOLD (15 * NL_PKT_BUF_SIZE)
#define NL_BATCH_RX_BUFSIZE NL_RCV_PKT_BUF_SIZE
static const struct message nlmsg_str[] = {{RTM_NEWROUTE, "RTM_NEWROUTE"},
{RTM_DELROUTE, "RTM_DELROUTE"},
{RTM_GETROUTE, "RTM_GETROUTE"},
{RTM_NEWLINK, "RTM_NEWLINK"},
{RTM_DELLINK, "RTM_DELLINK"},
{RTM_GETLINK, "RTM_GETLINK"},
{RTM_NEWADDR, "RTM_NEWADDR"},
{RTM_DELADDR, "RTM_DELADDR"},
{RTM_GETADDR, "RTM_GETADDR"},
{RTM_NEWNEIGH, "RTM_NEWNEIGH"},
{RTM_DELNEIGH, "RTM_DELNEIGH"},
{RTM_GETNEIGH, "RTM_GETNEIGH"},
{RTM_NEWRULE, "RTM_NEWRULE"},
{RTM_DELRULE, "RTM_DELRULE"},
{RTM_GETRULE, "RTM_GETRULE"},
{RTM_NEWNEXTHOP, "RTM_NEWNEXTHOP"},
{RTM_DELNEXTHOP, "RTM_DELNEXTHOP"},
{RTM_GETNEXTHOP, "RTM_GETNEXTHOP"},
{0}};
static const struct message rtproto_str[] = {
{RTPROT_REDIRECT, "redirect"},
{RTPROT_KERNEL, "kernel"},
{RTPROT_BOOT, "boot"},
{RTPROT_STATIC, "static"},
{RTPROT_GATED, "GateD"},
{RTPROT_RA, "router advertisement"},
{RTPROT_MRT, "MRT"},
{RTPROT_ZEBRA, "Zebra"},
#ifdef RTPROT_BIRD
{RTPROT_BIRD, "BIRD"},
#endif /* RTPROT_BIRD */
{RTPROT_MROUTED, "mroute"},
{RTPROT_BGP, "BGP"},
{RTPROT_OSPF, "OSPF"},
{RTPROT_ISIS, "IS-IS"},
{RTPROT_RIP, "RIP"},
{RTPROT_RIPNG, "RIPNG"},
{RTPROT_ZSTATIC, "static"},
{0}};
static const struct message family_str[] = {{AF_INET, "ipv4"},
{AF_INET6, "ipv6"},
{AF_BRIDGE, "bridge"},
{RTNL_FAMILY_IPMR, "ipv4MR"},
{RTNL_FAMILY_IP6MR, "ipv6MR"},
{0}};
static const struct message rttype_str[] = {{RTN_UNSPEC, "none"},
{RTN_UNICAST, "unicast"},
{RTN_LOCAL, "local"},
{RTN_BROADCAST, "broadcast"},
{RTN_ANYCAST, "anycast"},
{RTN_MULTICAST, "multicast"},
{RTN_BLACKHOLE, "blackhole"},
{RTN_UNREACHABLE, "unreachable"},
{RTN_PROHIBIT, "prohibited"},
{RTN_THROW, "throw"},
{RTN_NAT, "nat"},
{RTN_XRESOLVE, "resolver"},
{0}};
extern struct thread_master *master;
extern uint32_t nl_rcvbufsize;
extern struct zebra_privs_t zserv_privs;
DEFINE_MTYPE_STATIC(ZEBRA, NL_BUF, "Zebra Netlink buffers")
size_t nl_batch_tx_bufsize;
char *nl_batch_tx_buf;
char nl_batch_rx_buf[NL_BATCH_RX_BUFSIZE];
_Atomic uint32_t nl_batch_bufsize = NL_DEFAULT_BATCH_BUFSIZE;
_Atomic uint32_t nl_batch_send_threshold = NL_DEFAULT_BATCH_SEND_THRESHOLD;
struct nl_batch {
void *buf;
size_t bufsiz;
size_t limit;
void *buf_head;
size_t curlen;
size_t msgcnt;
const struct zebra_dplane_info *zns;
struct dplane_ctx_q ctx_list;
/*
* Pointer to the queue of completed contexts outbound back
* towards the dataplane module.
*/
struct dplane_ctx_q *ctx_out_q;
};
int netlink_config_write_helper(struct vty *vty)
{
uint32_t size =
atomic_load_explicit(&nl_batch_bufsize, memory_order_relaxed);
uint32_t threshold = atomic_load_explicit(&nl_batch_send_threshold,
memory_order_relaxed);
if (size != NL_DEFAULT_BATCH_BUFSIZE
|| threshold != NL_DEFAULT_BATCH_SEND_THRESHOLD)
vty_out(vty, "zebra kernel netlink batch-tx-buf %u %u\n", size,
threshold);
return 0;
}
void netlink_set_batch_buffer_size(uint32_t size, uint32_t threshold, bool set)
{
if (!set) {
size = NL_DEFAULT_BATCH_BUFSIZE;
threshold = NL_DEFAULT_BATCH_SEND_THRESHOLD;
}
atomic_store_explicit(&nl_batch_bufsize, size, memory_order_relaxed);
atomic_store_explicit(&nl_batch_send_threshold, threshold,
memory_order_relaxed);
}
int netlink_talk_filter(struct nlmsghdr *h, ns_id_t ns_id, int startup)
{
/*
* This is an error condition that must be handled during
* development.
*
* The netlink_talk_filter function is used for communication
* down the netlink_cmd pipe and we are expecting
* an ack being received. So if we get here
* then we did not receive the ack and instead
* received some other message in an unexpected
* way.
*/
zlog_debug("%s: ignoring message type 0x%04x(%s) NS %u", __func__,
h->nlmsg_type, nl_msg_type_to_str(h->nlmsg_type), ns_id);
return 0;
}
static int netlink_recvbuf(struct nlsock *nl, uint32_t newsize)
{
uint32_t oldsize;
socklen_t newlen = sizeof(newsize);
socklen_t oldlen = sizeof(oldsize);
int ret;
ret = getsockopt(nl->sock, SOL_SOCKET, SO_RCVBUF, &oldsize, &oldlen);
if (ret < 0) {
flog_err_sys(EC_LIB_SOCKET,
"Can't get %s receive buffer size: %s", nl->name,
safe_strerror(errno));
return -1;
}
/* Try force option (linux >= 2.6.14) and fall back to normal set */
frr_with_privs(&zserv_privs) {
ret = setsockopt(nl->sock, SOL_SOCKET, SO_RCVBUFFORCE,
&nl_rcvbufsize,
sizeof(nl_rcvbufsize));
}
if (ret < 0)
ret = setsockopt(nl->sock, SOL_SOCKET, SO_RCVBUF,
&nl_rcvbufsize, sizeof(nl_rcvbufsize));
if (ret < 0) {
flog_err_sys(EC_LIB_SOCKET,
"Can't set %s receive buffer size: %s", nl->name,
safe_strerror(errno));
return -1;
}
ret = getsockopt(nl->sock, SOL_SOCKET, SO_RCVBUF, &newsize, &newlen);
if (ret < 0) {
flog_err_sys(EC_LIB_SOCKET,
"Can't get %s receive buffer size: %s", nl->name,
safe_strerror(errno));
return -1;
}
zlog_info("Setting netlink socket receive buffer size: %u -> %u",
oldsize, newsize);
return 0;
}
/* Make socket for Linux netlink interface. */
static int netlink_socket(struct nlsock *nl, unsigned long groups,
ns_id_t ns_id)
{
int ret;
struct sockaddr_nl snl;
int sock;
int namelen;
frr_with_privs(&zserv_privs) {
sock = ns_socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE, ns_id);
if (sock < 0) {
zlog_err("Can't open %s socket: %s", nl->name,
safe_strerror(errno));
return -1;
}
memset(&snl, 0, sizeof(snl));
snl.nl_family = AF_NETLINK;
snl.nl_groups = groups;
/* Bind the socket to the netlink structure for anything. */
ret = bind(sock, (struct sockaddr *)&snl, sizeof(snl));
}
if (ret < 0) {
zlog_err("Can't bind %s socket to group 0x%x: %s", nl->name,
snl.nl_groups, safe_strerror(errno));
close(sock);
return -1;
}
/* multiple netlink sockets will have different nl_pid */
namelen = sizeof(snl);
ret = getsockname(sock, (struct sockaddr *)&snl, (socklen_t *)&namelen);
if (ret < 0 || namelen != sizeof(snl)) {
flog_err_sys(EC_LIB_SOCKET, "Can't get %s socket name: %s",
nl->name, safe_strerror(errno));
close(sock);
return -1;
}
nl->snl = snl;
nl->sock = sock;
return ret;
}
static int netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
int startup)
{
/*
* When we handle new message types here
* because we are starting to install them
* then lets check the netlink_install_filter
* and see if we should add the corresponding
* allow through entry there.
* Probably not needed to do but please
* think about it.
*/
switch (h->nlmsg_type) {
case RTM_NEWROUTE:
return netlink_route_change(h, ns_id, startup);
case RTM_DELROUTE:
return netlink_route_change(h, ns_id, startup);
case RTM_NEWLINK:
return netlink_link_change(h, ns_id, startup);
case RTM_DELLINK:
return netlink_link_change(h, ns_id, startup);
case RTM_NEWADDR:
return netlink_interface_addr(h, ns_id, startup);
case RTM_DELADDR:
return netlink_interface_addr(h, ns_id, startup);
case RTM_NEWNEIGH:
return netlink_neigh_change(h, ns_id);
case RTM_DELNEIGH:
return netlink_neigh_change(h, ns_id);
case RTM_GETNEIGH:
/*
* Kernel in some situations when it expects
* user space to resolve arp entries, we will
* receive this notification. As we don't
* need this notification and as that
* we don't want to spam the log file with
* below messages, just ignore.
*/
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("Received RTM_GETNEIGH, ignoring");
break;
case RTM_NEWRULE:
return netlink_rule_change(h, ns_id, startup);
case RTM_DELRULE:
return netlink_rule_change(h, ns_id, startup);
case RTM_NEWNEXTHOP:
return netlink_nexthop_change(h, ns_id, startup);
case RTM_DELNEXTHOP:
return netlink_nexthop_change(h, ns_id, startup);
default:
/*
* If we have received this message then
* we have made a mistake during development
* and we need to write some code to handle
* this message type or not ask for
* it to be sent up to us
*/
flog_err(EC_ZEBRA_UNKNOWN_NLMSG,
"Unknown netlink nlmsg_type %s(%d) vrf %u\n",
nl_msg_type_to_str(h->nlmsg_type), h->nlmsg_type,
ns_id);
break;
}
return 0;
}
static int kernel_read(struct thread *thread)
{
struct zebra_ns *zns = (struct zebra_ns *)THREAD_ARG(thread);
struct zebra_dplane_info dp_info;
/* Capture key info from ns struct */
zebra_dplane_info_from_zns(&dp_info, zns, false);
netlink_parse_info(netlink_information_fetch, &zns->netlink, &dp_info,
5, 0);
zns->t_netlink = NULL;
thread_add_read(zrouter.master, kernel_read, zns, zns->netlink.sock,
&zns->t_netlink);
return 0;
}
/*
* Filter out messages from self that occur on listener socket,
* caused by our actions on the command socket(s)
*
* When we add new Netlink message types we probably
* do not need to add them here as that we are filtering
* on the routes we actually care to receive( which is rarer
* then the normal course of operations). We are intentionally
* allowing some messages from ourselves through
* ( I'm looking at you Interface based netlink messages )
* so that we only had to write one way to handle incoming
* address add/delete changes.
*/
static void netlink_install_filter(int sock, __u32 pid, __u32 dplane_pid)
{
/*
* BPF_JUMP instructions and where you jump to are based upon
* 0 as being the next statement. So count from 0. Writing
* this down because every time I look at this I have to
* re-remember it.
*/
struct sock_filter filter[] = {
/*
* Logic:
* if (nlmsg_pid == pid ||
* nlmsg_pid == dplane_pid) {
* if (the incoming nlmsg_type ==
* RTM_NEWADDR | RTM_DELADDR)
* keep this message
* else
* skip this message
* } else
* keep this netlink message
*/
/*
* 0: Load the nlmsg_pid into the BPF register
*/
BPF_STMT(BPF_LD | BPF_ABS | BPF_W,
offsetof(struct nlmsghdr, nlmsg_pid)),
/*
* 1: Compare to pid
*/
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, htonl(pid), 1, 0),
/*
* 2: Compare to dplane pid
*/
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, htonl(dplane_pid), 0, 4),
/*
* 3: Load the nlmsg_type into BPF register
*/
BPF_STMT(BPF_LD | BPF_ABS | BPF_H,
offsetof(struct nlmsghdr, nlmsg_type)),
/*
* 4: Compare to RTM_NEWADDR
*/
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, htons(RTM_NEWADDR), 2, 0),
/*
* 5: Compare to RTM_DELADDR
*/
BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, htons(RTM_DELADDR), 1, 0),
/*
* 6: This is the end state of we want to skip the
* message
*/
BPF_STMT(BPF_RET | BPF_K, 0),
/* 7: This is the end state of we want to keep
* the message
*/
BPF_STMT(BPF_RET | BPF_K, 0xffff),
};
struct sock_fprog prog = {
.len = array_size(filter), .filter = filter,
};
if (setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER, &prog, sizeof(prog))
< 0)
flog_err_sys(EC_LIB_SOCKET, "Can't install socket filter: %s\n",
safe_strerror(errno));
}
void netlink_parse_rtattr(struct rtattr **tb, int max, struct rtattr *rta,
int len)
{
while (RTA_OK(rta, len)) {
if (rta->rta_type <= max)
tb[rta->rta_type] = rta;
rta = RTA_NEXT(rta, len);
}
}
/**
* netlink_parse_rtattr_nested() - Parses a nested route attribute
* @tb: Pointer to array for storing rtattr in.
* @max: Max number to store.
* @rta: Pointer to rtattr to look for nested items in.
*/
void netlink_parse_rtattr_nested(struct rtattr **tb, int max,
struct rtattr *rta)
{
netlink_parse_rtattr(tb, max, RTA_DATA(rta), RTA_PAYLOAD(rta));
}
bool nl_attr_put(struct nlmsghdr *n, unsigned int maxlen, int type,
const void *data, unsigned int alen)
{
int len;
struct rtattr *rta;
len = RTA_LENGTH(alen);
if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen)
return false;
rta = (struct rtattr *)(((char *)n) + NLMSG_ALIGN(n->nlmsg_len));
rta->rta_type = type;
rta->rta_len = len;
if (data)
memcpy(RTA_DATA(rta), data, alen);
else
assert(alen == 0);
n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
return true;
}
bool nl_attr_put16(struct nlmsghdr *n, unsigned int maxlen, int type,
uint16_t data)
{
return nl_attr_put(n, maxlen, type, &data, sizeof(uint16_t));
}
bool nl_attr_put32(struct nlmsghdr *n, unsigned int maxlen, int type,
uint32_t data)
{
return nl_attr_put(n, maxlen, type, &data, sizeof(uint32_t));
}
struct rtattr *nl_attr_nest(struct nlmsghdr *n, unsigned int maxlen, int type)
{
struct rtattr *nest = NLMSG_TAIL(n);
if (!nl_attr_put(n, maxlen, type, NULL, 0))
return NULL;
nest->rta_type |= NLA_F_NESTED;
return nest;
}
int nl_attr_nest_end(struct nlmsghdr *n, struct rtattr *nest)
{
nest->rta_len = (uint8_t *)NLMSG_TAIL(n) - (uint8_t *)nest;
return n->nlmsg_len;
}
struct rtnexthop *nl_attr_rtnh(struct nlmsghdr *n, unsigned int maxlen)
{
struct rtnexthop *rtnh = (struct rtnexthop *)NLMSG_TAIL(n);
if (NLMSG_ALIGN(n->nlmsg_len) + RTNH_ALIGN(sizeof(struct rtnexthop))
> maxlen)
return NULL;
memset(rtnh, 0, sizeof(struct rtnexthop));
n->nlmsg_len =
NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(sizeof(struct rtnexthop));
return rtnh;
}
void nl_attr_rtnh_end(struct nlmsghdr *n, struct rtnexthop *rtnh)
{
rtnh->rtnh_len = (uint8_t *)NLMSG_TAIL(n) - (uint8_t *)rtnh;
}
const char *nl_msg_type_to_str(uint16_t msg_type)
{
return lookup_msg(nlmsg_str, msg_type, "");
}
const char *nl_rtproto_to_str(uint8_t rtproto)
{
return lookup_msg(rtproto_str, rtproto, "");
}
const char *nl_family_to_str(uint8_t family)
{
return lookup_msg(family_str, family, "");
}
const char *nl_rttype_to_str(uint8_t rttype)
{
return lookup_msg(rttype_str, rttype, "");
}
#define NLA_OK(nla, len) \
((len) >= (int)sizeof(struct nlattr) \
&& (nla)->nla_len >= sizeof(struct nlattr) \
&& (nla)->nla_len <= (len))
#define NLA_NEXT(nla, attrlen) \
((attrlen) -= NLA_ALIGN((nla)->nla_len), \
(struct nlattr *)(((char *)(nla)) + NLA_ALIGN((nla)->nla_len)))
#define NLA_LENGTH(len) (NLA_ALIGN(sizeof(struct nlattr)) + (len))
#define NLA_DATA(nla) ((struct nlattr *)(((char *)(nla)) + NLA_LENGTH(0)))
#define ERR_NLA(err, inner_len) \
((struct nlattr *)(((char *)(err)) \
+ NLMSG_ALIGN(sizeof(struct nlmsgerr)) \
+ NLMSG_ALIGN((inner_len))))
static void netlink_parse_nlattr(struct nlattr **tb, int max,
struct nlattr *nla, int len)
{
while (NLA_OK(nla, len)) {
if (nla->nla_type <= max)
tb[nla->nla_type] = nla;
nla = NLA_NEXT(nla, len);
}
}
static void netlink_parse_extended_ack(struct nlmsghdr *h)
{
struct nlattr *tb[NLMSGERR_ATTR_MAX + 1] = {};
const struct nlmsgerr *err = (const struct nlmsgerr *)NLMSG_DATA(h);
const struct nlmsghdr *err_nlh = NULL;
/* Length not including nlmsghdr */
uint32_t len = 0;
/* Inner error netlink message length */
uint32_t inner_len = 0;
const char *msg = NULL;
uint32_t off = 0;
if (!(h->nlmsg_flags & NLM_F_CAPPED))
inner_len = (uint32_t)NLMSG_PAYLOAD(&err->msg, 0);
len = (uint32_t)(NLMSG_PAYLOAD(h, sizeof(struct nlmsgerr)) - inner_len);
netlink_parse_nlattr(tb, NLMSGERR_ATTR_MAX, ERR_NLA(err, inner_len),
len);
if (tb[NLMSGERR_ATTR_MSG])
msg = (const char *)NLA_DATA(tb[NLMSGERR_ATTR_MSG]);
if (tb[NLMSGERR_ATTR_OFFS]) {
off = *(uint32_t *)NLA_DATA(tb[NLMSGERR_ATTR_OFFS]);
if (off > h->nlmsg_len) {
zlog_err("Invalid offset for NLMSGERR_ATTR_OFFS");
} else if (!(h->nlmsg_flags & NLM_F_CAPPED)) {
/*
* Header of failed message
* we are not doing anything currently with it
* but noticing it for later.
*/
err_nlh = &err->msg;
zlog_debug("%s: Received %s extended Ack", __func__,
nl_msg_type_to_str(err_nlh->nlmsg_type));
}
}
if (msg && *msg != '\0') {
bool is_err = !!err->error;
if (is_err)
zlog_err("Extended Error: %s", msg);
else
flog_warn(EC_ZEBRA_NETLINK_EXTENDED_WARNING,
"Extended Warning: %s", msg);
}
}
/*
* netlink_send_msg - send a netlink message of a certain size.
*
* Returns -1 on error. Otherwise, it returns the number of bytes sent.
*/
static ssize_t netlink_send_msg(const struct nlsock *nl, void *buf,
size_t buflen)
{
struct sockaddr_nl snl = {};
struct iovec iov = {};
struct msghdr msg = {};
ssize_t status;
int save_errno = 0;
iov.iov_base = buf;
iov.iov_len = buflen;
msg.msg_name = &snl;
msg.msg_namelen = sizeof(snl);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
snl.nl_family = AF_NETLINK;
/* Send message to netlink interface. */
frr_with_privs(&zserv_privs) {
status = sendmsg(nl->sock, &msg, 0);
save_errno = errno;
}
if (IS_ZEBRA_DEBUG_KERNEL_MSGDUMP_SEND) {
zlog_debug("%s: >> netlink message dump [sent]", __func__);
zlog_hexdump(buf, buflen);
}
if (status == -1) {
flog_err_sys(EC_LIB_SOCKET, "%s error: %s", __func__,
safe_strerror(save_errno));
return -1;
}
return status;
}
/*
* netlink_recv_msg - receive a netlink message.
*
* Returns -1 on error, 0 if read would block or the number of bytes received.
*/
static int netlink_recv_msg(const struct nlsock *nl, struct msghdr msg,
void *buf, size_t buflen)
{
struct iovec iov;
int status;
iov.iov_base = buf;
iov.iov_len = buflen;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
do {
status = recvmsg(nl->sock, &msg, 0);
} while (status == -1 && errno == EINTR);
if (status == -1) {
if (errno == EWOULDBLOCK || errno == EAGAIN)
return 0;
flog_err(EC_ZEBRA_RECVMSG_OVERRUN, "%s recvmsg overrun: %s",
nl->name, safe_strerror(errno));
/*
* In this case we are screwed. There is no good way to recover
* zebra at this point.
*/
exit(-1);
}
if (status == 0) {
flog_err_sys(EC_LIB_SOCKET, "%s EOF", nl->name);
return -1;
}
if (msg.msg_namelen != sizeof(struct sockaddr_nl)) {
flog_err(EC_ZEBRA_NETLINK_LENGTH_ERROR,
"%s sender address length error: length %d", nl->name,
msg.msg_namelen);
return -1;
}
if (IS_ZEBRA_DEBUG_KERNEL_MSGDUMP_RECV) {
zlog_debug("%s: << netlink message dump [recv]", __func__);
zlog_hexdump(buf, status);
}
return status;
}
/*
* netlink_parse_error - parse a netlink error message
*
* Returns 1 if this message is acknowledgement, 0 if this error should be
* ignored, -1 otherwise.
*/
static int netlink_parse_error(const struct nlsock *nl, struct nlmsghdr *h,
const struct zebra_dplane_info *zns,
bool startup)
{
struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h);
int errnum = err->error;
int msg_type = err->msg.nlmsg_type;
if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
flog_err(EC_ZEBRA_NETLINK_LENGTH_ERROR,
"%s error: message truncated", nl->name);
return -1;
}
/*
* Parse the extended information before we actually handle it. At this
* point in time we do not do anything other than report the issue.
*/
if (h->nlmsg_flags & NLM_F_ACK_TLVS)
netlink_parse_extended_ack(h);
/* If the error field is zero, then this is an ACK. */
if (err->error == 0) {
if (IS_ZEBRA_DEBUG_KERNEL) {
zlog_debug("%s: %s ACK: type=%s(%u), seq=%u, pid=%u",
__func__, nl->name,
nl_msg_type_to_str(err->msg.nlmsg_type),
err->msg.nlmsg_type, err->msg.nlmsg_seq,
err->msg.nlmsg_pid);
}
return 1;
}
/* Deal with errors that occur because of races in link handling. */
if (zns->is_cmd
&& ((msg_type == RTM_DELROUTE
&& (-errnum == ENODEV || -errnum == ESRCH))
|| (msg_type == RTM_NEWROUTE
&& (-errnum == ENETDOWN || -errnum == EEXIST)))) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: error: %s type=%s(%u), seq=%u, pid=%u",
nl->name, safe_strerror(-errnum),
nl_msg_type_to_str(msg_type), msg_type,
err->msg.nlmsg_seq, err->msg.nlmsg_pid);
return 0;
}
/*
* We see RTM_DELNEIGH when shutting down an interface with an IPv4
* link-local. The kernel should have already deleted the neighbor so
* do not log these as an error.
*/
if (msg_type == RTM_DELNEIGH
|| (zns->is_cmd && msg_type == RTM_NEWROUTE
&& (-errnum == ESRCH || -errnum == ENETUNREACH))) {
/*
* This is known to happen in some situations, don't log as
* error.
*/
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s error: %s, type=%s(%u), seq=%u, pid=%u",
nl->name, safe_strerror(-errnum),
nl_msg_type_to_str(msg_type), msg_type,
err->msg.nlmsg_seq, err->msg.nlmsg_pid);
} else {
if ((msg_type != RTM_GETNEXTHOP) || !startup)
flog_err(EC_ZEBRA_UNEXPECTED_MESSAGE,
"%s error: %s, type=%s(%u), seq=%u, pid=%u",
nl->name, safe_strerror(-errnum),
nl_msg_type_to_str(msg_type), msg_type,
err->msg.nlmsg_seq, err->msg.nlmsg_pid);
}
return -1;
}
/*
* netlink_parse_info
*
* Receive message from netlink interface and pass those information
* to the given function.
*
* filter -> Function to call to read the results
* nl -> netlink socket information
* zns -> The zebra namespace data
* count -> How many we should read in, 0 means as much as possible
* startup -> Are we reading in under startup conditions? passed to
* the filter.
*/
int netlink_parse_info(int (*filter)(struct nlmsghdr *, ns_id_t, int),
const struct nlsock *nl,
const struct zebra_dplane_info *zns,
int count, int startup)
{
int status;
int ret = 0;
int error;
int read_in = 0;
while (1) {
char buf[NL_RCV_PKT_BUF_SIZE];
struct sockaddr_nl snl;
struct msghdr msg = {.msg_name = (void *)&snl,
.msg_namelen = sizeof(snl)};
struct nlmsghdr *h;
if (count && read_in >= count)
return 0;
status = netlink_recv_msg(nl, msg, buf, sizeof(buf));
if (status == -1)
return -1;
else if (status == 0)
break;
read_in++;
for (h = (struct nlmsghdr *)buf;
(status >= 0 && NLMSG_OK(h, (unsigned int)status));
h = NLMSG_NEXT(h, status)) {
/* Finish of reading. */
if (h->nlmsg_type == NLMSG_DONE)
return ret;
/* Error handling. */
if (h->nlmsg_type == NLMSG_ERROR) {
int err = netlink_parse_error(nl, h, zns,
startup);
if (err == 1) {
if (!(h->nlmsg_flags & NLM_F_MULTI))
return 0;
continue;
} else
return err;
}
/* OK we got netlink message. */
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug(
"netlink_parse_info: %s type %s(%u), len=%d, seq=%u, pid=%u",
nl->name,
nl_msg_type_to_str(h->nlmsg_type),
h->nlmsg_type, h->nlmsg_len,
h->nlmsg_seq, h->nlmsg_pid);
/*
* Ignore messages that maybe sent from
* other actors besides the kernel
*/
if (snl.nl_pid != 0) {
zlog_debug("Ignoring message from pid %u",
snl.nl_pid);
continue;
}
error = (*filter)(h, zns->ns_id, startup);
if (error < 0) {
zlog_debug("%s filter function error",
nl->name);
ret = error;
}
}
/* After error care. */
if (msg.msg_flags & MSG_TRUNC) {
flog_err(EC_ZEBRA_NETLINK_LENGTH_ERROR,
"%s error: message truncated", nl->name);
continue;
}
if (status) {
flog_err(EC_ZEBRA_NETLINK_LENGTH_ERROR,
"%s error: data remnant size %d", nl->name,
status);
return -1;
}
}
return ret;
}
/*
* netlink_talk_info
*
* sendmsg() to netlink socket then recvmsg().
* Calls netlink_parse_info to parse returned data
*
* filter -> The filter to read final results from kernel
* nlmsghdr -> The data to send to the kernel
* dp_info -> The dataplane and netlink socket information
* startup -> Are we reading in under startup conditions
* This is passed through eventually to filter.
*/
static int
netlink_talk_info(int (*filter)(struct nlmsghdr *, ns_id_t, int startup),
struct nlmsghdr *n, const struct zebra_dplane_info *dp_info,
int startup)
{
const struct nlsock *nl;
nl = &(dp_info->nls);
n->nlmsg_seq = nl->seq;
n->nlmsg_pid = nl->snl.nl_pid;
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug(
"netlink_talk: %s type %s(%u), len=%d seq=%u flags 0x%x",
nl->name, nl_msg_type_to_str(n->nlmsg_type),
n->nlmsg_type, n->nlmsg_len, n->nlmsg_seq,
n->nlmsg_flags);
if (netlink_send_msg(nl, n, n->nlmsg_len) == -1)
return -1;
/*
* Get reply from netlink socket.
* The reply should either be an acknowlegement or an error.
*/
return netlink_parse_info(filter, nl, dp_info, 0, startup);
}
/*
* Synchronous version of netlink_talk_info. Converts args to suit the
* common version, which is suitable for both sync and async use.
*/
int netlink_talk(int (*filter)(struct nlmsghdr *, ns_id_t, int startup),
struct nlmsghdr *n, struct nlsock *nl, struct zebra_ns *zns,
int startup)
{
struct zebra_dplane_info dp_info;
/* Increment sequence number before capturing snapshot of ns socket
* info.
*/
nl->seq++;
/* Capture info in intermediate info struct */
zebra_dplane_info_from_zns(&dp_info, zns, (nl == &(zns->netlink_cmd)));
return netlink_talk_info(filter, n, &dp_info, startup);
}
/* Issue request message to kernel via netlink socket. GET messages
* are issued through this interface.
*/
int netlink_request(struct nlsock *nl, void *req)
{
struct nlmsghdr *n = (struct nlmsghdr *)req;
/* Check netlink socket. */
if (nl->sock < 0) {
flog_err_sys(EC_LIB_SOCKET, "%s socket isn't active.",
nl->name);
return -1;
}
/* Fill common fields for all requests. */
n->nlmsg_pid = nl->snl.nl_pid;
n->nlmsg_seq = ++nl->seq;
if (netlink_send_msg(nl, req, n->nlmsg_len) == -1)
return -1;
return 0;
}
static int nl_batch_read_resp(struct nl_batch *bth)
{
struct nlmsghdr *h;
struct sockaddr_nl snl;
struct msghdr msg = {};
int status, seq;
const struct nlsock *nl;
struct zebra_dplane_ctx *ctx;
bool ignore_msg;
nl = &(bth->zns->nls);
msg.msg_name = (void *)&snl;
msg.msg_namelen = sizeof(snl);
/*
* The responses are not batched, so we need to read and process one
* message at a time.
*/
while (true) {
status = netlink_recv_msg(nl, msg, nl_batch_rx_buf,
sizeof(nl_batch_rx_buf));
if (status == -1 || status == 0)
return status;
h = (struct nlmsghdr *)nl_batch_rx_buf;
ignore_msg = false;
seq = h->nlmsg_seq;
/*
* Find the corresponding context object. Received responses are
* in the same order as requests we sent, so we can simply
* iterate over the context list and match responses with
* requests at same time.
*/
while (true) {
ctx = dplane_ctx_dequeue(&(bth->ctx_list));
if (ctx == NULL)
break;
dplane_ctx_enqueue_tail(bth->ctx_out_q, ctx);
/* We have found corresponding context object. */
if (dplane_ctx_get_ns(ctx)->nls.seq == seq)
break;
/*
* 'update' context objects take two consecutive
* sequence numbers.
*/
if (dplane_ctx_is_update(ctx)
&& dplane_ctx_get_ns(ctx)->nls.seq + 1 == seq) {
/*
* This is the situation where we get a response
* to a message that should be ignored.
*/
ignore_msg = true;
break;
}
}
if (ignore_msg)
continue;
/*
* We received a message with the sequence number that isn't
* associated with any dplane context object.
*/
if (ctx == NULL) {
zlog_debug(
"%s: skipping unassociated response, seq number %d NS %u",
__func__, h->nlmsg_seq, bth->zns->ns_id);
continue;
}
if (h->nlmsg_type == NLMSG_ERROR) {
int err = netlink_parse_error(nl, h, bth->zns, 0);
if (err == -1)
dplane_ctx_set_status(
ctx, ZEBRA_DPLANE_REQUEST_FAILURE);
zlog_debug("%s: netlink error message seq=%d ",
__func__, h->nlmsg_seq);
continue;
}
/*
* If we get here then we did not receive neither the ack nor
* the error and instead received some other message in an
* unexpected way.
*/
zlog_debug("%s: ignoring message type 0x%04x(%s) NS %u",
__func__, h->nlmsg_type,
nl_msg_type_to_str(h->nlmsg_type), bth->zns->ns_id);
}
return 0;
}
static void nl_batch_reset(struct nl_batch *bth)
{
bth->buf_head = bth->buf;
bth->curlen = 0;
bth->msgcnt = 0;
bth->zns = NULL;
TAILQ_INIT(&(bth->ctx_list));
}
static void nl_batch_init(struct nl_batch *bth, struct dplane_ctx_q *ctx_out_q)
{
/*
* If the size of the buffer has changed, free and then allocate a new
* one.
*/
size_t bufsize =
atomic_load_explicit(&nl_batch_bufsize, memory_order_relaxed);
if (bufsize != nl_batch_tx_bufsize) {
if (nl_batch_tx_buf)
XFREE(MTYPE_NL_BUF, nl_batch_tx_buf);
nl_batch_tx_buf = XCALLOC(MTYPE_NL_BUF, bufsize);
nl_batch_tx_bufsize = bufsize;
}
bth->buf = nl_batch_tx_buf;
bth->bufsiz = bufsize;
bth->limit = atomic_load_explicit(&nl_batch_send_threshold,
memory_order_relaxed);
bth->ctx_out_q = ctx_out_q;
nl_batch_reset(bth);
}
static void nl_batch_send(struct nl_batch *bth)
{
struct zebra_dplane_ctx *ctx;
bool err = false;
if (bth->curlen != 0 && bth->zns != NULL) {
if (IS_ZEBRA_DEBUG_KERNEL)
zlog_debug("%s: %s, batch size=%zu, msg cnt=%zu",
__func__, bth->zns->nls.name, bth->curlen,
bth->msgcnt);
if (netlink_send_msg(&(bth->zns->nls), bth->buf, bth->curlen)
== -1)
err = true;
if (!err) {
if (nl_batch_read_resp(bth) == -1)
err = true;
}
}
/* Move remaining contexts to the outbound queue. */
while (true) {
ctx = dplane_ctx_dequeue(&(bth->ctx_list));
if (ctx == NULL)
break;
if (err)
dplane_ctx_set_status(ctx,
ZEBRA_DPLANE_REQUEST_FAILURE);
dplane_ctx_enqueue_tail(bth->ctx_out_q, ctx);
}
nl_batch_reset(bth);
}
enum netlink_msg_status netlink_batch_add_msg(
struct nl_batch *bth, struct zebra_dplane_ctx *ctx,
ssize_t (*msg_encoder)(struct zebra_dplane_ctx *, void *, size_t),
bool ignore_res)
{
int seq;
ssize_t size;
struct nlmsghdr *msgh;
size = (*msg_encoder)(ctx, bth->buf_head, bth->bufsiz - bth->curlen);
/*
* If there was an error while encoding the message (other than buffer
* overflow) then return an error.
*/
if (size < 0)
return FRR_NETLINK_ERROR;
/*
* If the message doesn't fit entirely in the buffer then send the batch
* and retry.
*/
if (size == 0) {
nl_batch_send(bth);
size = (*msg_encoder)(ctx, bth->buf_head,
bth->bufsiz - bth->curlen);
/*
* If the message doesn't fit in the empty buffer then just
* return an error.
*/
if (size <= 0)
return FRR_NETLINK_ERROR;
}
seq = dplane_ctx_get_ns(ctx)->nls.seq;
if (ignore_res)
seq++;
msgh = (struct nlmsghdr *)bth->buf_head;
msgh->nlmsg_seq = seq;
msgh->nlmsg_pid = dplane_ctx_get_ns(ctx)->nls.snl.nl_pid;
bth->zns = dplane_ctx_get_ns(ctx);
bth->buf_head = ((char *)bth->buf_head) + size;
bth->curlen += size;
bth->msgcnt++;
return FRR_NETLINK_QUEUED;
}
static enum netlink_msg_status nl_put_msg(struct nl_batch *bth,
struct zebra_dplane_ctx *ctx)
{
if (dplane_ctx_is_skip_kernel(ctx))
return FRR_NETLINK_SUCCESS;
switch (dplane_ctx_get_op(ctx)) {
case DPLANE_OP_ROUTE_INSTALL:
case DPLANE_OP_ROUTE_UPDATE:
case DPLANE_OP_ROUTE_DELETE:
return netlink_put_route_update_msg(bth, ctx);
case DPLANE_OP_NH_INSTALL:
case DPLANE_OP_NH_UPDATE:
case DPLANE_OP_NH_DELETE:
return netlink_put_nexthop_update_msg(bth, ctx);
case DPLANE_OP_LSP_INSTALL:
case DPLANE_OP_LSP_UPDATE:
case DPLANE_OP_LSP_DELETE:
return netlink_put_lsp_update_msg(bth, ctx);
case DPLANE_OP_PW_INSTALL:
case DPLANE_OP_PW_UNINSTALL:
return netlink_put_pw_update_msg(bth, ctx);
case DPLANE_OP_ADDR_INSTALL:
case DPLANE_OP_ADDR_UNINSTALL:
return netlink_put_address_update_msg(bth, ctx);
case DPLANE_OP_MAC_INSTALL:
case DPLANE_OP_MAC_DELETE:
return netlink_put_mac_update_msg(bth, ctx);
case DPLANE_OP_NEIGH_INSTALL:
case DPLANE_OP_NEIGH_UPDATE:
case DPLANE_OP_NEIGH_DELETE:
case DPLANE_OP_VTEP_ADD:
case DPLANE_OP_VTEP_DELETE:
case DPLANE_OP_NEIGH_DISCOVER:
return netlink_put_neigh_update_msg(bth, ctx);
case DPLANE_OP_RULE_ADD:
case DPLANE_OP_RULE_DELETE:
case DPLANE_OP_RULE_UPDATE:
return netlink_put_rule_update_msg(bth, ctx);
case DPLANE_OP_SYS_ROUTE_ADD:
case DPLANE_OP_SYS_ROUTE_DELETE:
case DPLANE_OP_ROUTE_NOTIFY:
case DPLANE_OP_LSP_NOTIFY:
return FRR_NETLINK_SUCCESS;
case DPLANE_OP_NONE:
return FRR_NETLINK_ERROR;
}
return FRR_NETLINK_ERROR;
}
void kernel_update_multi(struct dplane_ctx_q *ctx_list)
{
struct nl_batch batch;
struct zebra_dplane_ctx *ctx;
struct dplane_ctx_q handled_list;
enum netlink_msg_status res;
TAILQ_INIT(&handled_list);
nl_batch_init(&batch, &handled_list);
while (true) {
ctx = dplane_ctx_dequeue(ctx_list);
if (ctx == NULL)
break;
if (batch.zns != NULL
&& batch.zns->ns_id != dplane_ctx_get_ns(ctx)->ns_id)
nl_batch_send(&batch);
/*
* Assume all messages will succeed and then mark only the ones
* that failed.
*/
dplane_ctx_set_status(ctx, ZEBRA_DPLANE_REQUEST_SUCCESS);
res = nl_put_msg(&batch, ctx);
dplane_ctx_enqueue_tail(&(batch.ctx_list), ctx);
if (res == FRR_NETLINK_ERROR)
dplane_ctx_set_status(ctx,
ZEBRA_DPLANE_REQUEST_FAILURE);
if (batch.curlen > batch.limit)
nl_batch_send(&batch);
}
nl_batch_send(&batch);
TAILQ_INIT(ctx_list);
dplane_ctx_list_append(ctx_list, &handled_list);
}
/* Exported interface function. This function simply calls
netlink_socket (). */
void kernel_init(struct zebra_ns *zns)
{
uint32_t groups;
#if defined SOL_NETLINK
int one, ret;
#endif
/*
* Initialize netlink sockets
*
* If RTMGRP_XXX exists use that, but at some point
* I think the kernel developers realized that
* keeping track of all the different values would
* lead to confusion, so we need to convert the
* RTNLGRP_XXX to a bit position for ourself
*/
groups = RTMGRP_LINK |
RTMGRP_IPV4_ROUTE |
RTMGRP_IPV4_IFADDR |
RTMGRP_IPV6_ROUTE |
RTMGRP_IPV6_IFADDR |
RTMGRP_IPV4_MROUTE |
RTMGRP_NEIGH |
((uint32_t) 1 << (RTNLGRP_IPV4_RULE - 1)) |
((uint32_t) 1 << (RTNLGRP_IPV6_RULE - 1)) |
((uint32_t) 1 << (RTNLGRP_NEXTHOP - 1));
snprintf(zns->netlink.name, sizeof(zns->netlink.name),
"netlink-listen (NS %u)", zns->ns_id);
zns->netlink.sock = -1;
if (netlink_socket(&zns->netlink, groups, zns->ns_id) < 0) {
zlog_err("Failure to create %s socket",
zns->netlink.name);
exit(-1);
}
snprintf(zns->netlink_cmd.name, sizeof(zns->netlink_cmd.name),
"netlink-cmd (NS %u)", zns->ns_id);
zns->netlink_cmd.sock = -1;
if (netlink_socket(&zns->netlink_cmd, 0, zns->ns_id) < 0) {
zlog_err("Failure to create %s socket",
zns->netlink_cmd.name);
exit(-1);
}
snprintf(zns->netlink_dplane.name, sizeof(zns->netlink_dplane.name),
"netlink-dp (NS %u)", zns->ns_id);
zns->netlink_dplane.sock = -1;
if (netlink_socket(&zns->netlink_dplane, 0, zns->ns_id) < 0) {
zlog_err("Failure to create %s socket",
zns->netlink_dplane.name);
exit(-1);
}
/*
* SOL_NETLINK is not available on all platforms yet
* apparently. It's in bits/socket.h which I am not
* sure that we want to pull into our build system.
*/
#if defined SOL_NETLINK
/*
* Let's tell the kernel that we want to receive extended
* ACKS over our command socket(s)
*/
one = 1;
ret = setsockopt(zns->netlink_cmd.sock, SOL_NETLINK, NETLINK_EXT_ACK,
&one, sizeof(one));
if (ret < 0)
zlog_notice("Registration for extended cmd ACK failed : %d %s",
errno, safe_strerror(errno));
one = 1;
ret = setsockopt(zns->netlink_dplane.sock, SOL_NETLINK, NETLINK_EXT_ACK,
&one, sizeof(one));
if (ret < 0)
zlog_notice("Registration for extended dp ACK failed : %d %s",
errno, safe_strerror(errno));
/*
* Trim off the payload of the original netlink message in the
* acknowledgment. This option is available since Linux 4.2, so if
* setsockopt fails, ignore the error.
*/
one = 1;
ret = setsockopt(zns->netlink_dplane.sock, SOL_NETLINK, NETLINK_CAP_ACK,
&one, sizeof(one));
if (ret < 0)
zlog_notice(
"Registration for reduced ACK packet size failed, probably running an early kernel");
#endif
/* Register kernel socket. */
if (fcntl(zns->netlink.sock, F_SETFL, O_NONBLOCK) < 0)
flog_err_sys(EC_LIB_SOCKET, "Can't set %s socket flags: %s",
zns->netlink.name, safe_strerror(errno));
if (fcntl(zns->netlink_cmd.sock, F_SETFL, O_NONBLOCK) < 0)
zlog_err("Can't set %s socket error: %s(%d)",
zns->netlink_cmd.name, safe_strerror(errno), errno);
if (fcntl(zns->netlink_dplane.sock, F_SETFL, O_NONBLOCK) < 0)
zlog_err("Can't set %s socket error: %s(%d)",
zns->netlink_dplane.name, safe_strerror(errno), errno);
/* Set receive buffer size if it's set from command line */
if (nl_rcvbufsize) {
netlink_recvbuf(&zns->netlink, nl_rcvbufsize);
netlink_recvbuf(&zns->netlink_cmd, nl_rcvbufsize);
netlink_recvbuf(&zns->netlink_dplane, nl_rcvbufsize);
}
netlink_install_filter(zns->netlink.sock,
zns->netlink_cmd.snl.nl_pid,
zns->netlink_dplane.snl.nl_pid);
zns->t_netlink = NULL;
thread_add_read(zrouter.master, kernel_read, zns,
zns->netlink.sock, &zns->t_netlink);
rt_netlink_init();
}
void kernel_terminate(struct zebra_ns *zns, bool complete)
{
THREAD_READ_OFF(zns->t_netlink);
if (zns->netlink.sock >= 0) {
close(zns->netlink.sock);
zns->netlink.sock = -1;
}
if (zns->netlink_cmd.sock >= 0) {
close(zns->netlink_cmd.sock);
zns->netlink_cmd.sock = -1;
}
/* During zebra shutdown, we need to leave the dataplane socket
* around until all work is done.
*/
if (complete) {
if (zns->netlink_dplane.sock >= 0) {
close(zns->netlink_dplane.sock);
zns->netlink_dplane.sock = -1;
}
}
}
#endif /* HAVE_NETLINK */