diff options
Diffstat (limited to 'src/grp-udev/libudev-core/net/link-config.c')
| -rw-r--r-- | src/grp-udev/libudev-core/net/link-config.c | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/src/grp-udev/libudev-core/net/link-config.c b/src/grp-udev/libudev-core/net/link-config.c new file mode 100644 index 0000000000..350cd24e9c --- /dev/null +++ b/src/grp-udev/libudev-core/net/link-config.c @@ -0,0 +1,519 @@ +/*** + 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 <systemd/sd-netlink.h> + +#include "alloc-util.h" +#include "conf-files.h" +#include "conf-parser.h" +#include "ethtool-util.h" +#include "fd-util.h" +#include "libudev-private.h" +#include "link-config.h" +#include "log.h" +#include "missing.h" +#include "netlink-util.h" +#include "network-internal.h" +#include "parse-util.h" +#include "path-util.h" +#include "proc-cmdline.h" +#include "random-util.h" +#include "stat-util.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "util.h" + +struct link_config_ctx { + LIST_HEAD(link_config, links); + + int ethtool_fd; + + bool enable_name_policy; + + sd_netlink *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}; + +static void link_config_free(link_config *link) { + if (!link) + return; + + free(link->filename); + + free(link->match_mac); + strv_free(link->match_path); + strv_free(link->match_driver); + strv_free(link->match_type); + free(link->match_name); + free(link->match_host); + free(link->match_virt); + free(link->match_kernel); + free(link->match_arch); + + free(link->description); + free(link->mac); + free(link->name_policy); + free(link->name); + free(link->alias); + + free(link); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(link_config*, link_config_free); + +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) + link_config_free(link); +} + +void link_config_ctx_free(link_config_ctx *ctx) { + if (!ctx) + return; + + safe_close(ctx->ethtool_fd); + + sd_netlink_unref(ctx->rtnl); + + link_configs_free(ctx); + + free(ctx); + + return; +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(link_config_ctx*, link_config_ctx_free); + +int link_config_ctx_new(link_config_ctx **ret) { + _cleanup_(link_config_ctx_freep) 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 load_link(link_config_ctx *ctx, const char *filename) { + _cleanup_(link_config_freep) 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); + + if (link->mtu > UINT_MAX || link->speed > UINT_MAX) + return -ERANGE; + + 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_errno(r, "Failed to read /proc/cmdline, ignoring: %m"); + 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 command line, 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) + return log_error_errno(r, "failed to enumerate link files: %m"); + + 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; + + assert(ctx); + assert(device); + assert(ret); + + LIST_FOREACH(links, link, ctx->links) { + const char* attr_value; + + attr_value = udev_device_get_sysattr_value(device, "address"); + + if (net_match_config(link->match_mac, link->match_path, link->match_driver, + link->match_type, link->match_name, link->match_host, + link->match_virt, link->match_kernel, link->match_arch, + attr_value ? ether_aton(attr_value) : NULL, + 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), + udev_device_get_sysname(device))) { + if (link->match_name) { + unsigned char name_assign_type = NET_NAME_UNKNOWN; + + attr_value = udev_device_get_sysattr_value(device, "name_assign_type"); + if (attr_value) + (void) safe_atou8(attr_value, &name_assign_type); + + if (name_assign_type == NET_NAME_ENUM) { + log_warning("Config file %s applies to device based on potentially unpredictable interface name '%s'", + link->filename, udev_device_get_sysname(device)); + *ret = link; + + return 0; + } else if (name_assign_type == NET_NAME_RENAMED) { + log_warning("Config file %s matches device based on renamed interface name '%s', ignoring", + link->filename, udev_device_get_sysname(device)); + + continue; + } + } + + 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; + + /* if we can't get the assign type, assume it is not random */ + s = udev_device_get_sysattr_value(device, "addr_assign_type"); + if (!s) + return false; + + 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; + + /* if we can't get the assgin type, assume we should rename */ + s = udev_device_get_sysattr_value(device, "name_assign_type"); + if (!s) + return true; + + r = safe_atou(s, &type); + if (r < 0) + return true; + + switch (type) { + case NET_NAME_USER: + case NET_NAME_RENAMED: + /* these were already named by userspace, do not touch again */ + return false; + case NET_NAME_PREDICTABLE: + /* the kernel claims to have given a predictable name */ + if (respect_predictable) + return false; + /* fall through */ + case NET_NAME_ENUM: + default: + /* the name is known to be bad, or of an unknown type */ + return true; + } +} + +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 { + uint64_t result; + + 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); + + 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_errno(r, "Could not set speed or duplex of %s to %zu Mbps (%s): %m", + old_name, config->speed / 1024, + duplex_to_string(config->duplex)); + + r = ethtool_set_wol(&ctx->ethtool_fd, old_name, config->wol); + if (r < 0) + log_warning_errno(r, "Could not set WakeOnLan of %s to %s: %m", + old_name, wol_to_string(config->wol)); + + 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_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 not set by policy, fall back manually set name */ + if (!new_name) + new_name = config->name; + } else + new_name = NULL; + + switch (config->mac_policy) { + case MACPOLICY_PERSISTENT: + if (mac_is_random(device)) { + r = get_mac(device, false, &generated_mac); + if (r == -ENOENT) { + log_warning_errno(r, "Could not generate persistent MAC address for %s: %m", old_name); + 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) { + log_warning_errno(r, "Could not generate random MAC address for %s: %m", old_name); + break; + } else if (r < 0) + return r; + mac = &generated_mac; + } + break; + case MACPOLICY_NONE: + default: + mac = config->mac; + } + + r = rtnl_set_link_properties(&ctx->rtnl, ifindex, config->alias, mac, config->mtu); + if (r < 0) + return log_warning_errno(r, "Could not set Alias, MACAddress or MTU on %s: %m", old_name); + + *name = new_name; + + return 0; +} + +int link_get_driver(link_config_ctx *ctx, struct udev_device *device, char **ret) { + const char *name; + char *driver = NULL; + int 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", + [MACPOLICY_NONE] = "none" +}; + +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"); |