diff options
Diffstat (limited to 'src/nspawn/nspawn-network.c')
-rw-r--r-- | src/nspawn/nspawn-network.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/src/nspawn/nspawn-network.c b/src/nspawn/nspawn-network.c new file mode 100644 index 0000000000..51ba8554e0 --- /dev/null +++ b/src/nspawn/nspawn-network.c @@ -0,0 +1,441 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + 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 "sd-id128.h" +#include "sd-netlink.h" +#include "libudev.h" + +#include "util.h" +#include "ether-addr-util.h" +#include "siphash24.h" +#include "netlink-util.h" +#include "udev-util.h" + +#include "nspawn.h" +#include "nspawn-network.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 MACVLAN_HASH_KEY SD_ID128_MAKE(00,13,6d,bc,66,83,44,81,bb,0c,f9,51,1f,24,a6,6f) + +static int generate_mac( + const char *machine_name, + struct ether_addr *mac, + sd_id128_t hash_key, + uint64_t idx) { + + uint8_t result[8]; + 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. */ + siphash24(result, 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; +} + +int setup_veth(const char *machine_name, + pid_t pid, + char iface_name[IFNAMSIZ], + bool bridge) { + + _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL; + _cleanup_netlink_unref_ sd_netlink *rtnl = NULL; + struct ether_addr mac_host, mac_container; + int r, i; + + /* 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 = 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, iface_name); + 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, "host0"); + 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 (host0, %s): %m", iface_name); + + 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_bridge(const char *veth_name, const char *bridge_name) { + _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL; + _cleanup_netlink_unref_ sd_netlink *rtnl = NULL; + int r, bridge_ifi; + + assert(veth_name); + assert(bridge_name); + + bridge_ifi = (int) if_nametoindex(bridge_name); + if (bridge_ifi <= 0) + return log_error_errno(errno, "Failed to resolve interface %s: %m", bridge_name); + + r = sd_netlink_open(&rtnl); + if (r < 0) + return log_error_errno(r, "Failed to connect to netlink: %m"); + + r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0); + if (r < 0) + return log_error_errno(r, "Failed to allocate netlink message: %m"); + + r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP); + if (r < 0) + return log_error_errno(r, "Failed to set IFF_UP flag: %m"); + + r = sd_netlink_message_append_string(m, IFLA_IFNAME, veth_name); + if (r < 0) + return log_error_errno(r, "Failed to add netlink interface name field: %m"); + + r = sd_netlink_message_append_u32(m, IFLA_MASTER, bridge_ifi); + if (r < 0) + return log_error_errno(r, "Failed to add netlink master field: %m"); + + r = sd_netlink_call(rtnl, m, 0, NULL); + if (r < 0) + return log_error_errno(r, "Failed to add veth interface to bridge: %m"); + + return bridge_ifi; +} + +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_netlink_unref_ 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_netlink_message_unref_ 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_netlink_unref_ 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_netlink_message_unref_ 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_netlink_unref_ 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_netlink_message_unref_ 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; +} |