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Diffstat (limited to 'src/nspawn/nspawn-network.c')
-rw-r--r--src/nspawn/nspawn-network.c694
1 files changed, 0 insertions, 694 deletions
diff --git a/src/nspawn/nspawn-network.c b/src/nspawn/nspawn-network.c
deleted file mode 100644
index 8da47a2ca6..0000000000
--- a/src/nspawn/nspawn-network.c
+++ /dev/null
@@ -1,694 +0,0 @@
-/***
- This file is part of systemd.
-
- Copyright 2015 Lennart Poettering
-
- 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 <linux/veth.h>
-#include <net/if.h>
-
-#include "libudev.h"
-#include "sd-id128.h"
-#include "sd-netlink.h"
-
-#include "alloc-util.h"
-#include "ether-addr-util.h"
-#include "lockfile-util.h"
-#include "netlink-util.h"
-#include "nspawn-network.h"
-#include "siphash24.h"
-#include "socket-util.h"
-#include "stat-util.h"
-#include "string-util.h"
-#include "udev-util.h"
-#include "util.h"
-
-#define HOST_HASH_KEY SD_ID128_MAKE(1a,37,6f,c7,46,ec,45,0b,ad,a3,d5,31,06,60,5d,b1)
-#define CONTAINER_HASH_KEY SD_ID128_MAKE(c3,c4,f9,19,b5,57,b2,1c,e6,cf,14,27,03,9c,ee,a2)
-#define VETH_EXTRA_HOST_HASH_KEY SD_ID128_MAKE(48,c7,f6,b7,ea,9d,4c,9e,b7,28,d4,de,91,d5,bf,66)
-#define VETH_EXTRA_CONTAINER_HASH_KEY SD_ID128_MAKE(af,50,17,61,ce,f9,4d,35,84,0d,2b,20,54,be,ce,59)
-#define MACVLAN_HASH_KEY SD_ID128_MAKE(00,13,6d,bc,66,83,44,81,bb,0c,f9,51,1f,24,a6,6f)
-
-static int remove_one_link(sd_netlink *rtnl, const char *name) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- int r;
-
- if (isempty(name))
- return 0;
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_DELLINK, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to allocate netlink message: %m");
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, name);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface name: %m");
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r == -ENODEV) /* Already gone */
- return 0;
- if (r < 0)
- return log_error_errno(r, "Failed to remove interface %s: %m", name);
-
- return 1;
-}
-
-static int generate_mac(
- const char *machine_name,
- struct ether_addr *mac,
- sd_id128_t hash_key,
- uint64_t idx) {
-
- uint64_t result;
- size_t l, sz;
- uint8_t *v, *i;
- int r;
-
- l = strlen(machine_name);
- sz = sizeof(sd_id128_t) + l;
- if (idx > 0)
- sz += sizeof(idx);
-
- v = alloca(sz);
-
- /* fetch some persistent data unique to the host */
- r = sd_id128_get_machine((sd_id128_t*) v);
- if (r < 0)
- return r;
-
- /* combine with some data unique (on this host) to this
- * container instance */
- i = mempcpy(v + sizeof(sd_id128_t), machine_name, l);
- if (idx > 0) {
- idx = htole64(idx);
- memcpy(i, &idx, sizeof(idx));
- }
-
- /* Let's hash the host machine ID plus the container name. We
- * use a fixed, but originally randomly created hash key here. */
- result = htole64(siphash24(v, sz, hash_key.bytes));
-
- assert_cc(ETH_ALEN <= sizeof(result));
- memcpy(mac->ether_addr_octet, &result, ETH_ALEN);
-
- /* see eth_random_addr in the kernel */
- mac->ether_addr_octet[0] &= 0xfe; /* clear multicast bit */
- mac->ether_addr_octet[0] |= 0x02; /* set local assignment bit (IEEE802) */
-
- return 0;
-}
-
-static int add_veth(
- sd_netlink *rtnl,
- pid_t pid,
- const char *ifname_host,
- const struct ether_addr *mac_host,
- const char *ifname_container,
- const struct ether_addr *mac_container) {
-
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- int r;
-
- assert(rtnl);
- assert(ifname_host);
- assert(mac_host);
- assert(ifname_container);
- assert(mac_container);
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to allocate netlink message: %m");
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, ifname_host);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface name: %m");
-
- r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, mac_host);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
- r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "veth");
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_open_container(m, VETH_INFO_PEER);
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, ifname_container);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface name: %m");
-
- r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, mac_container);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return log_error_errno(r, "Failed to add new veth interfaces (%s:%s): %m", ifname_host, ifname_container);
-
- return 0;
-}
-
-int setup_veth(const char *machine_name,
- pid_t pid,
- char iface_name[IFNAMSIZ],
- bool bridge) {
-
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- struct ether_addr mac_host, mac_container;
- int r, i;
-
- assert(machine_name);
- assert(pid > 0);
- assert(iface_name);
-
- /* Use two different interface name prefixes depending whether
- * we are in bridge mode or not. */
- snprintf(iface_name, IFNAMSIZ - 1, "%s-%s",
- bridge ? "vb" : "ve", machine_name);
-
- r = generate_mac(machine_name, &mac_container, CONTAINER_HASH_KEY, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to generate predictable MAC address for container side: %m");
-
- r = generate_mac(machine_name, &mac_host, HOST_HASH_KEY, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to generate predictable MAC address for host side: %m");
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- r = add_veth(rtnl, pid, iface_name, &mac_host, "host0", &mac_container);
- if (r < 0)
- return r;
-
- i = (int) if_nametoindex(iface_name);
- if (i <= 0)
- return log_error_errno(errno, "Failed to resolve interface %s: %m", iface_name);
-
- return i;
-}
-
-int setup_veth_extra(
- const char *machine_name,
- pid_t pid,
- char **pairs) {
-
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- uint64_t idx = 0;
- char **a, **b;
- int r;
-
- assert(machine_name);
- assert(pid > 0);
-
- if (strv_isempty(pairs))
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- STRV_FOREACH_PAIR(a, b, pairs) {
- struct ether_addr mac_host, mac_container;
-
- r = generate_mac(machine_name, &mac_container, VETH_EXTRA_CONTAINER_HASH_KEY, idx);
- if (r < 0)
- return log_error_errno(r, "Failed to generate predictable MAC address for container side of extra veth link: %m");
-
- r = generate_mac(machine_name, &mac_host, VETH_EXTRA_HOST_HASH_KEY, idx);
- if (r < 0)
- return log_error_errno(r, "Failed to generate predictable MAC address for container side of extra veth link: %m");
-
- r = add_veth(rtnl, pid, *a, &mac_host, *b, &mac_container);
- if (r < 0)
- return r;
-
- idx++;
- }
-
- return 0;
-}
-
-static int join_bridge(sd_netlink *rtnl, const char *veth_name, const char *bridge_name) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- int r, bridge_ifi;
-
- assert(rtnl);
- assert(veth_name);
- assert(bridge_name);
-
- bridge_ifi = (int) if_nametoindex(bridge_name);
- if (bridge_ifi <= 0)
- return -errno;
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0);
- if (r < 0)
- return r;
-
- r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, veth_name);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_append_u32(m, IFLA_MASTER, bridge_ifi);
- if (r < 0)
- return r;
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return r;
-
- return bridge_ifi;
-}
-
-static int create_bridge(sd_netlink *rtnl, const char *bridge_name) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- int r;
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, bridge_name);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "bridge");
- if (r < 0)
- return r;
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return r;
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return r;
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return r;
-
- return 0;
-}
-
-int setup_bridge(const char *veth_name, const char *bridge_name, bool create) {
- _cleanup_release_lock_file_ LockFile bridge_lock = LOCK_FILE_INIT;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- int r, bridge_ifi;
- unsigned n = 0;
-
- assert(veth_name);
- assert(bridge_name);
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- if (create) {
- /* We take a system-wide lock here, so that we can safely check whether there's still a member in the
- * bridge before removing it, without risking interferance from other nspawn instances. */
-
- r = make_lock_file("/run/systemd/nspawn-network-zone", LOCK_EX, &bridge_lock);
- if (r < 0)
- return log_error_errno(r, "Failed to take network zone lock: %m");
- }
-
- for (;;) {
- bridge_ifi = join_bridge(rtnl, veth_name, bridge_name);
- if (bridge_ifi >= 0)
- return bridge_ifi;
- if (bridge_ifi != -ENODEV || !create || n > 10)
- return log_error_errno(bridge_ifi, "Failed to add interface %s to bridge %s: %m", veth_name, bridge_name);
-
- /* Count attempts, so that we don't enter an endless loop here. */
- n++;
-
- /* The bridge doesn't exist yet. Let's create it */
- r = create_bridge(rtnl, bridge_name);
- if (r < 0)
- return log_error_errno(r, "Failed to create bridge interface %s: %m", bridge_name);
-
- /* Try again, now that the bridge exists */
- }
-}
-
-int remove_bridge(const char *bridge_name) {
- _cleanup_release_lock_file_ LockFile bridge_lock = LOCK_FILE_INIT;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- const char *path;
- int r;
-
- /* Removes the specified bridge, but only if it is currently empty */
-
- if (isempty(bridge_name))
- return 0;
-
- r = make_lock_file("/run/systemd/nspawn-network-zone", LOCK_EX, &bridge_lock);
- if (r < 0)
- return log_error_errno(r, "Failed to take network zone lock: %m");
-
- path = strjoina("/sys/class/net/", bridge_name, "/brif");
-
- r = dir_is_empty(path);
- if (r == -ENOENT) /* Already gone? */
- return 0;
- if (r < 0)
- return log_error_errno(r, "Can't detect if bridge %s is empty: %m", bridge_name);
- if (r == 0) /* Still populated, leave it around */
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- return remove_one_link(rtnl, bridge_name);
-}
-
-static int parse_interface(struct udev *udev, const char *name) {
- _cleanup_udev_device_unref_ struct udev_device *d = NULL;
- char ifi_str[2 + DECIMAL_STR_MAX(int)];
- int ifi;
-
- ifi = (int) if_nametoindex(name);
- if (ifi <= 0)
- return log_error_errno(errno, "Failed to resolve interface %s: %m", name);
-
- sprintf(ifi_str, "n%i", ifi);
- d = udev_device_new_from_device_id(udev, ifi_str);
- if (!d)
- return log_error_errno(errno, "Failed to get udev device for interface %s: %m", name);
-
- if (udev_device_get_is_initialized(d) <= 0) {
- log_error("Network interface %s is not initialized yet.", name);
- return -EBUSY;
- }
-
- return ifi;
-}
-
-int move_network_interfaces(pid_t pid, char **ifaces) {
- _cleanup_udev_unref_ struct udev *udev = NULL;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- char **i;
- int r;
-
- if (strv_isempty(ifaces))
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- udev = udev_new();
- if (!udev) {
- log_error("Failed to connect to udev.");
- return -ENOMEM;
- }
-
- STRV_FOREACH(i, ifaces) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- int ifi;
-
- ifi = parse_interface(udev, *i);
- if (ifi < 0)
- return ifi;
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, ifi);
- if (r < 0)
- return log_error_errno(r, "Failed to allocate netlink message: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
- if (r < 0)
- return log_error_errno(r, "Failed to append namespace PID to netlink message: %m");
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return log_error_errno(r, "Failed to move interface %s to namespace: %m", *i);
- }
-
- return 0;
-}
-
-int setup_macvlan(const char *machine_name, pid_t pid, char **ifaces) {
- _cleanup_udev_unref_ struct udev *udev = NULL;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- unsigned idx = 0;
- char **i;
- int r;
-
- if (strv_isempty(ifaces))
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- udev = udev_new();
- if (!udev) {
- log_error("Failed to connect to udev.");
- return -ENOMEM;
- }
-
- STRV_FOREACH(i, ifaces) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- _cleanup_free_ char *n = NULL;
- struct ether_addr mac;
- int ifi;
-
- ifi = parse_interface(udev, *i);
- if (ifi < 0)
- return ifi;
-
- r = generate_mac(machine_name, &mac, MACVLAN_HASH_KEY, idx++);
- if (r < 0)
- return log_error_errno(r, "Failed to create MACVLAN MAC address: %m");
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to allocate netlink message: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface index: %m");
-
- n = strappend("mv-", *i);
- if (!n)
- return log_oom();
-
- strshorten(n, IFNAMSIZ-1);
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface name: %m");
-
- r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
- r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "macvlan");
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_MACVLAN_MODE, MACVLAN_MODE_BRIDGE);
- if (r < 0)
- return log_error_errno(r, "Failed to append macvlan mode: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return log_error_errno(r, "Failed to add new macvlan interfaces: %m");
- }
-
- return 0;
-}
-
-int setup_ipvlan(const char *machine_name, pid_t pid, char **ifaces) {
- _cleanup_udev_unref_ struct udev *udev = NULL;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- char **i;
- int r;
-
- if (strv_isempty(ifaces))
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- udev = udev_new();
- if (!udev) {
- log_error("Failed to connect to udev.");
- return -ENOMEM;
- }
-
- STRV_FOREACH(i, ifaces) {
- _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
- _cleanup_free_ char *n = NULL;
- int ifi;
-
- ifi = parse_interface(udev, *i);
- if (ifi < 0)
- return ifi;
-
- r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to allocate netlink message: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface index: %m");
-
- n = strappend("iv-", *i);
- if (!n)
- return log_oom();
-
- strshorten(n, IFNAMSIZ-1);
-
- r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink interface name: %m");
-
- r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
- if (r < 0)
- return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
- r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "ipvlan");
- if (r < 0)
- return log_error_errno(r, "Failed to open netlink container: %m");
-
- r = sd_netlink_message_append_u16(m, IFLA_IPVLAN_MODE, IPVLAN_MODE_L2);
- if (r < 0)
- return log_error_errno(r, "Failed to add ipvlan mode: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_message_close_container(m);
- if (r < 0)
- return log_error_errno(r, "Failed to close netlink container: %m");
-
- r = sd_netlink_call(rtnl, m, 0, NULL);
- if (r < 0)
- return log_error_errno(r, "Failed to add new ipvlan interfaces: %m");
- }
-
- return 0;
-}
-
-int veth_extra_parse(char ***l, const char *p) {
- _cleanup_free_ char *a = NULL, *b = NULL;
- int r;
-
- r = extract_first_word(&p, &a, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
- if (r < 0)
- return r;
- if (r == 0 || !ifname_valid(a))
- return -EINVAL;
-
- r = extract_first_word(&p, &b, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
- if (r < 0)
- return r;
- if (r == 0 || !ifname_valid(b)) {
- free(b);
- b = strdup(a);
- if (!b)
- return -ENOMEM;
- }
-
- if (p)
- return -EINVAL;
-
- r = strv_push_pair(l, a, b);
- if (r < 0)
- return -ENOMEM;
-
- a = b = NULL;
- return 0;
-}
-
-int remove_veth_links(const char *primary, char **pairs) {
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- char **a, **b;
- int r;
-
- /* In some cases the kernel might pin the veth links between host and container even after the namespace
- * died. Hence, let's better remove them explicitly too. */
-
- if (isempty(primary) && strv_isempty(pairs))
- return 0;
-
- r = sd_netlink_open(&rtnl);
- if (r < 0)
- return log_error_errno(r, "Failed to connect to netlink: %m");
-
- remove_one_link(rtnl, primary);
-
- STRV_FOREACH_PAIR(a, b, pairs)
- remove_one_link(rtnl, *a);
-
- return 0;
-}