link-config.c revision 04b67d49254d956d31bcfe80340fb9df7ed332d3
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
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 <netinet/ether.h>
#include <linux/netdevice.h>
#include "sd-id128.h"
#include "missing.h"
#include "link-config.h"
#include "ethtool-util.h"
#include "libudev-private.h"
#include "sd-rtnl.h"
#include "util.h"
#include "log.h"
#include "strv.h"
#include "path-util.h"
#include "conf-parser.h"
#include "conf-files.h"
#include "fileio.h"
#include "hashmap.h"
#include "rtnl-util.h"
#include "network-internal.h"
#include "siphash24.h"
struct link_config_ctx {
LIST_HEAD(link_config, links);
int ethtool_fd;
bool enable_name_policy;
sd_rtnl *rtnl;
usec_t link_dirs_ts_usec;
};
static const char* const link_dirs[] = {
"/etc/systemd/network",
"/run/systemd/network",
"/usr/lib/systemd/network",
#ifdef HAVE_SPLIT_USR
"/lib/systemd/network",
#endif
NULL};
DEFINE_TRIVIAL_CLEANUP_FUNC(link_config_ctx*, link_config_ctx_free);
#define _cleanup_link_config_ctx_free_ _cleanup_(link_config_ctx_freep)
int link_config_ctx_new(link_config_ctx **ret) {
_cleanup_link_config_ctx_free_ link_config_ctx *ctx = NULL;
if (!ret)
return -EINVAL;
ctx = new0(link_config_ctx, 1);
if (!ctx)
return -ENOMEM;
LIST_HEAD_INIT(ctx->links);
ctx->ethtool_fd = -1;
ctx->enable_name_policy = true;
*ret = ctx;
ctx = NULL;
return 0;
}
static int link_config_ctx_connect(link_config_ctx *ctx) {
int r;
if (ctx->ethtool_fd == -1) {
r = ethtool_connect(&ctx->ethtool_fd);
if (r < 0) {
log_warning("link_config: could not connect to ethtool: %s",
strerror(-r));
return r;
}
}
if (!ctx->rtnl) {
r = sd_rtnl_open(&ctx->rtnl, 0);
if (r < 0) {
log_warning("link_config: could not connect to rtnl: %s",
strerror(-r));
return r;
}
}
return 0;
}
static void link_configs_free(link_config_ctx *ctx) {
link_config *link, *link_next;
if (!ctx)
return;
LIST_FOREACH_SAFE(links, link, link_next, ctx->links) {
free(link->filename);
free(link->match_path);
free(link->match_driver);
free(link->match_type);
free(link->description);
free(link->alias);
free(link->name_policy);
free(link);
}
}
void link_config_ctx_free(link_config_ctx *ctx) {
if (!ctx)
return;
safe_close(ctx->ethtool_fd);
sd_rtnl_unref(ctx->rtnl);
link_configs_free(ctx);
free(ctx);
return;
}
static int load_link(link_config_ctx *ctx, const char *filename) {
_cleanup_free_ link_config *link = NULL;
_cleanup_fclose_ FILE *file = NULL;
int r;
assert(ctx);
assert(filename);
file = fopen(filename, "re");
if (!file) {
if (errno == ENOENT)
return 0;
else
return -errno;
}
if (null_or_empty_fd(fileno(file))) {
log_debug("Skipping empty file: %s", filename);
return 0;
}
link = new0(link_config, 1);
if (!link)
return log_oom();
link->mac_policy = _MACPOLICY_INVALID;
link->wol = _WOL_INVALID;
link->duplex = _DUP_INVALID;
r = config_parse(NULL, filename, file,
"Match\0Link\0Ethernet\0",
config_item_perf_lookup, link_config_gperf_lookup,
false, false, true, link);
if (r < 0)
return r;
else
log_debug("Parsed configuration file %s", filename);
link->filename = strdup(filename);
LIST_PREPEND(links, ctx->links, link);
link = NULL;
return 0;
}
static bool enable_name_policy(void) {
_cleanup_free_ char *line = NULL;
const char *word, *state;
int r;
size_t l;
r = proc_cmdline(&line);
if (r < 0)
log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
if (r <= 0)
return true;
FOREACH_WORD_QUOTED(word, l, line, state)
if (strneq(word, "net.ifnames=0", l))
return false;
return true;
}
int link_config_load(link_config_ctx *ctx) {
int r;
_cleanup_strv_free_ char **files;
char **f;
link_configs_free(ctx);
if (!enable_name_policy()) {
ctx->enable_name_policy = false;
log_info("Network interface NamePolicy= disabled on kernel commandline, ignoring.");
}
/* update timestamp */
paths_check_timestamp(link_dirs, &ctx->link_dirs_ts_usec, true);
r = conf_files_list_strv(&files, ".link", NULL, link_dirs);
if (r < 0) {
log_error("failed to enumerate link files: %s", strerror(-r));
return r;
}
STRV_FOREACH_BACKWARDS(f, files) {
r = load_link(ctx, *f);
if (r < 0)
return r;
}
return 0;
}
bool link_config_should_reload(link_config_ctx *ctx) {
return paths_check_timestamp(link_dirs, &ctx->link_dirs_ts_usec, false);
}
int link_config_get(link_config_ctx *ctx, struct udev_device *device, link_config **ret) {
link_config *link;
LIST_FOREACH(links, link, ctx->links) {
if (net_match_config(link->match_mac, link->match_path, link->match_driver,
link->match_type, NULL, link->match_host,
link->match_virt, link->match_kernel, link->match_arch,
ether_aton(udev_device_get_sysattr_value(device, "address")),
udev_device_get_property_value(device, "ID_PATH"),
udev_device_get_driver(udev_device_get_parent(device)),
udev_device_get_property_value(device, "ID_NET_DRIVER"),
udev_device_get_devtype(device),
NULL)) {
log_debug("Config file %s applies to device %s",
link->filename,
udev_device_get_sysname(device));
*ret = link;
return 0;
}
}
*ret = NULL;
return -ENOENT;
}
static bool mac_is_random(struct udev_device *device) {
const char *s;
unsigned type;
int r;
s = udev_device_get_sysattr_value(device, "addr_assign_type");
if (!s)
return false; /* if we don't know, assume it is not random */
r = safe_atou(s, &type);
if (r < 0)
return false;
return type == NET_ADDR_RANDOM;
}
static bool should_rename(struct udev_device *device, bool respect_predictable) {
const char *s;
unsigned type;
int r;
s = udev_device_get_sysattr_value(device, "name_assign_type");
if (!s)
return true; /* if we don't know, assume we should rename */
r = safe_atou(s, &type);
if (r < 0)
return true;
switch (type) {
case NET_NAME_USER:
case NET_NAME_RENAMED:
return false; /* these were already named by userspace, do not touch again */
case NET_NAME_PREDICTABLE:
if (respect_predictable)
return false; /* the kernel claims to have given a predictable name */
/* fall through */
case NET_NAME_ENUM:
default:
return true; /* the name is known to be bad, or of an unknown type */
}
}
static int get_mac(struct udev_device *device, bool want_random, struct ether_addr *mac) {
int r;
if (want_random)
random_bytes(mac->ether_addr_octet, ETH_ALEN);
else {
uint8_t result[8];
r = net_get_unique_predictable_data(device, result);
if (r < 0)
return r;
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 link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_device *device, const char **name) {
const char *old_name;
const char *new_name = NULL;
struct ether_addr generated_mac;
struct ether_addr *mac = NULL;
bool respect_predictable = false;
int r, ifindex;
assert(ctx);
assert(config);
assert(device);
assert(name);
r = link_config_ctx_connect(ctx);
if (r < 0)
return r;
old_name = udev_device_get_sysname(device);
if (!old_name)
return -EINVAL;
r = ethtool_set_speed(ctx->ethtool_fd, old_name, config->speed / 1024, config->duplex);
if (r < 0)
log_warning("Could not set speed or duplex of %s to %u Mbps (%s): %s",
old_name, config->speed / 1024, duplex_to_string(config->duplex),
strerror(-r));
r = ethtool_set_wol(ctx->ethtool_fd, old_name, config->wol);
if (r < 0)
log_warning("Could not set WakeOnLan of %s to %s: %s",
old_name, wol_to_string(config->wol), strerror(-r));
ifindex = udev_device_get_ifindex(device);
if (ifindex <= 0) {
log_warning("Could not find ifindex");
return -ENODEV;
}
if (ctx->enable_name_policy && config->name_policy) {
NamePolicy *policy;
for (policy = config->name_policy; !respect_predictable && !new_name &&
*policy != _NAMEPOLICY_INVALID; policy++) {
switch (*policy) {
case NAMEPOLICY_KERNEL:
respect_predictable = true;
break;
case NAMEPOLICY_DATABASE:
new_name = udev_device_get_property_value(device, "ID_NET_NAME_FROM_DATABASE");
break;
case NAMEPOLICY_ONBOARD:
new_name = udev_device_get_property_value(device, "ID_NET_NAME_ONBOARD");
break;
case NAMEPOLICY_SLOT:
new_name = udev_device_get_property_value(device, "ID_NET_NAME_SLOT");
break;
case NAMEPOLICY_PATH:
new_name = udev_device_get_property_value(device, "ID_NET_NAME_PATH");
break;
case NAMEPOLICY_MAC:
new_name = udev_device_get_property_value(device, "ID_NET_NAME_MAC");
break;
default:
break;
}
}
}
if (should_rename(device, respect_predictable)) {
if (!new_name)
/* if not set by policy, fall back manually set name */
new_name = config->name;
} else
new_name = NULL;
*name = new_name;
switch (config->mac_policy) {
case MACPOLICY_PERSISTENT:
if (mac_is_random(device)) {
r = get_mac(device, false, &generated_mac);
if (r == -ENOENT)
break;
else if (r < 0)
return r;
mac = &generated_mac;
}
break;
case MACPOLICY_RANDOM:
if (!mac_is_random(device)) {
r = get_mac(device, true, &generated_mac);
if (r == -ENOENT)
break;
else if (r < 0)
return r;
mac = &generated_mac;
}
break;
default:
mac = config->mac;
}
r = rtnl_set_link_properties(ctx->rtnl, ifindex, config->alias, mac, config->mtu);
if (r < 0) {
log_warning("Could not set Alias, MACAddress or MTU on %s: %s", old_name, strerror(-r));
return r;
}
return 0;
}
int link_get_driver(link_config_ctx *ctx, struct udev_device *device, char **ret) {
const char *name;
char *driver;
int r;
r = link_config_ctx_connect(ctx);
if (r < 0)
return r;
name = udev_device_get_sysname(device);
if (!name)
return -EINVAL;
r = ethtool_get_driver(ctx->ethtool_fd, name, &driver);
if (r < 0)
return r;
*ret = driver;
return 0;
}
static const char* const mac_policy_table[_MACPOLICY_MAX] = {
[MACPOLICY_PERSISTENT] = "persistent",
[MACPOLICY_RANDOM] = "random"
};
DEFINE_STRING_TABLE_LOOKUP(mac_policy, MACPolicy);
DEFINE_CONFIG_PARSE_ENUM(config_parse_mac_policy, mac_policy, MACPolicy, "Failed to parse MAC address policy");
static const char* const name_policy_table[_NAMEPOLICY_MAX] = {
[NAMEPOLICY_KERNEL] = "kernel",
[NAMEPOLICY_DATABASE] = "database",
[NAMEPOLICY_ONBOARD] = "onboard",
[NAMEPOLICY_SLOT] = "slot",
[NAMEPOLICY_PATH] = "path",
[NAMEPOLICY_MAC] = "mac"
};
DEFINE_STRING_TABLE_LOOKUP(name_policy, NamePolicy);
DEFINE_CONFIG_PARSE_ENUMV(config_parse_name_policy, name_policy, NamePolicy, _NAMEPOLICY_INVALID, "Failed to parse interface name policy");