#include <netinet/ether.h>

#include <net/if.h>

#include "sd-id128.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 "net-util.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 >= 0 && ctx->rtnl)

return 0;

r = ethtool_connect(&ctx->ethtool_fd);

if (r < 0)

return r;

r = sd_rtnl_open(0, &ctx->rtnl);

if (r < 0)

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);

}

}

void link_config_ctx_free(link_config_ctx *ctx) {

if (!ctx)

return;

if (ctx->ethtool_fd >= 0)

close_nointr_nofail(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) {

link_config *link;

_cleanup_fclose_ FILE *file;

int r;

assert(ctx);

assert(filename);

file = fopen(filename, "re");

if (!file) {

if (errno == ENOENT)

return 0;

else

return errno;

}

link = new0(link_config, 1);

if (!link) {

r = log_oom();

goto failure;

}

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,

(void*) link_config_gperf_lookup, false, false, link);

if (r < 0) {

log_warning("Could not parse config file %s: %s", filename, strerror(-r));

goto failure;

} else

log_debug("Parsed configuration file %s", filename);

link->filename = strdup(filename);

LIST_PREPEND(links, ctx->links, link);

return 0;

failure:

free(link);

return r;

}

static bool enable_name_policy(void) {

_cleanup_free_ char *line;

char *w, *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(w, l, line, state)

if (strneq(w, "net.ifnames=0", l))

return false;

return true;

}

int link_config_load(link_config_ctx *ctx) {

int r;

char **files, **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,

udev_device_get_sysattr_value(device, "address"),

udev_device_get_property_value(device, "ID_PATH"),

udev_device_get_driver(device),

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;

/* check for NET_ADDR_RANDOM */

return type == 1;

}

static bool mac_is_permanent(struct udev_device *device) {

const char *s;

unsigned type;

int r;

s = udev_device_get_sysattr_value(device, "addr_assign_type");

if (!s)

return true; /* if we don't know, assume it is permanent */

r = safe_atou(s, &type);

if (r < 0)

return true;

/* check for NET_ADDR_PERM */

return type == 0;

}

#define HASH_KEY SD_ID128_MAKE(d3,1e,48,fa,90,fe,4b,4c,9d,af,d5,d7,a1,b1,2e,8a)

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 {

const char *name;

uint8_t result[8];

size_t l, sz;

uint8_t *v;

/* fetch some persistent data unique (on this machine) to this device */

name = udev_device_get_property_value(device, "ID_NET_NAME_ONBOARD");

if (!name) {

name = udev_device_get_property_value(device, "ID_NET_NAME_SLOT");

if (!name) {

name = udev_device_get_property_value(device, "ID_NET_NAME_PATH");

if (!name)

return -ENOENT;

}

}

l = strlen(name);

sz = sizeof(sd_id128_t) + l;

v = alloca(sz);

/* fetch some persistent data unique to this machine */

r = sd_id128_get_machine((sd_id128_t*) v);

if (r < 0)

return r;

memcpy(v + sizeof(sd_id128_t), name, l);

/* Let's hash the machine ID plus the device name. We

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 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;

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, config->duplex);

if (r < 0)

log_warning("Could not set speed or duplex of %s to %u Mbytes (%s): %s",

old_name, config->speed, 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; !new_name && *policy != _NAMEPOLICY_INVALID; policy++) {

switch (*policy) {

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 (new_name)

*name = new_name; /* a name was set by a policy */

else if (config->name)

*name = config->name; /* a name was set manually in the config */

else

*name = NULL;

switch (config->mac_policy) {

case MACPOLICY_PERSISTENT:

if (!mac_is_permanent(device)) {

r = get_mac(device, false, &generated_mac);

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 < 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;

}

static const char* const mac_policy_table[] = {

[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_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");