chiark / gitweb /
udev: link-config - only set *name on success
[elogind.git] / src / udev / net / link-config.c
index 7686d87f80766004c3d730eebe1e135709e2ee53..64ff00dc0df40bc291515dc051712ae2e182cf8f 100644 (file)
   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);
 
-        char **link_dirs;
-        usec_t *link_dirs_ts_usec;
+        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) {
-        link_config_ctx *ctx;
+        _cleanup_link_config_ctx_free_ link_config_ctx *ctx = NULL;
 
         if (!ret)
                 return -EINVAL;
@@ -47,28 +78,37 @@ int link_config_ctx_new(link_config_ctx **ret) {
 
         LIST_HEAD_INIT(ctx->links);
 
-        ctx->link_dirs = strv_new("/etc/net/links",
-                                  "/run/net/links",
-                                  "/usr/lib/net/links",
-                                  NULL);
-        if (!ctx->link_dirs) {
-                log_error("failed to build link config directory array");
-                link_config_ctx_free(ctx);
-                return -ENOMEM;
-        }
-        if (!path_strv_canonicalize_uniq(ctx->link_dirs)) {
-                log_error("failed to canonicalize link config directories\n");
-                link_config_ctx_free(ctx);
-                return -ENOMEM;
+        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;
+                }
         }
 
-        ctx->link_dirs_ts_usec = calloc(strv_length(ctx->link_dirs), sizeof(usec_t));
-        if(!ctx->link_dirs_ts_usec) {
-                link_config_ctx_free(ctx);
-                return -ENOMEM;
+        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;
+                }
         }
 
-        *ret = ctx;
         return 0;
 }
 
@@ -84,6 +124,8 @@ static void link_configs_free(link_config_ctx *ctx) {
                 free(link->match_driver);
                 free(link->match_type);
                 free(link->description);
+                free(link->alias);
+                free(link->name_policy);
 
                 free(link);
         }
@@ -93,8 +135,10 @@ void link_config_ctx_free(link_config_ctx *ctx) {
         if (!ctx)
                 return;
 
-        strv_free(ctx->link_dirs);
-        free(ctx->link_dirs_ts_usec);
+        safe_close(ctx->ethtool_fd);
+
+        sd_rtnl_unref(ctx->rtnl);
+
         link_configs_free(ctx);
 
         free(ctx);
@@ -103,53 +147,87 @@ void link_config_ctx_free(link_config_ctx *ctx) {
 }
 
 static int load_link(link_config_ctx *ctx, const char *filename) {
-        link_config *link;
-        FILE *file;
+        _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;
+                        return -errno;
         }
 
-        link = new0(link_config, 1);
-        if (!link) {
-                r = log_oom();
-                goto failure;
+        if (null_or_empty_fd(fileno(file))) {
+                log_debug("Skipping empty file: %s", filename);
+                return 0;
         }
 
-        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("Colud not parse config file %s: %s", filename, strerror(-r));
-                goto failure;
-        } else
-                log_info("Parsed configuration file %s", filename);
+        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;
 
-failure:
-        free(link);
-        return r;
+        return true;
 }
 
 int link_config_load(link_config_ctx *ctx) {
         int r;
-        char **files, **f;
+        _cleanup_strv_free_ char **files;
+        char **f;
 
         link_configs_free(ctx);
 
-        /* update timestamps */
-        paths_check_timestamp(ctx->link_dirs, ctx->link_dirs_ts_usec, true);
+        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, (const char **)ctx->link_dirs);
+        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;
@@ -165,80 +243,265 @@ int link_config_load(link_config_ctx *ctx) {
 }
 
 bool link_config_should_reload(link_config_ctx *ctx) {
-        return paths_check_timestamp(ctx->link_dirs, ctx->link_dirs_ts_usec, false);
+        return paths_check_timestamp(link_dirs, &ctx->link_dirs_ts_usec, false);
 }
 
-static bool match_config(link_config *match, struct udev_device *device) {
-        const char *property;
+int link_config_get(link_config_ctx *ctx, struct udev_device *device,
+                    link_config **ret) {
+        link_config *link;
 
-        if (match->match_mac) {
-                property = udev_device_get_sysattr_value(device, "address");
-                if (!property || !streq(match->match_mac, property)) {
-                        log_debug("Device MAC address (%s) did not match MACAddress=%s", property, match->match_mac);
+        LIST_FOREACH(links, link, ctx->links) {
+                const char* 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, NULL, 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),
+                                     NULL)) {
+                        log_debug("Config file %s applies to device %s",
+                                  link->filename,
+                                  udev_device_get_sysname(device));
+                        *ret = link;
                         return 0;
                 }
         }
 
-        if (match->match_path) {
-                property = udev_device_get_property_value(device, "ID_PATH");
-                if (!property || !streq(match->match_path, property)) {
-                        log_debug("Device's persistent path (%s) did not match Path=%s", property, match->match_path);
-                        return 0;
-                }
-        }
+        *ret = NULL;
 
-        if (match->match_driver) {
-                property = udev_device_get_driver(device);
-                if (!property || !streq(match->match_driver, property)) {
-                        log_debug("Device driver (%s) did not match Driver=%s", property, match->match_driver);
-                        return 0;
-                }
+        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;
         }
+}
 
-        if (match->match_type) {
-                property = udev_device_get_devtype(device);
-                if (!property || !streq(match->match_type, property)) {
-                        log_debug("Device type (%s) did not match Type=%s", property, match->match_type);
-                        return 0;
-                }
+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);
         }
 
-        return 1;
+        /* 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_get(link_config_ctx *ctx, struct udev_device *device, link_config **ret) {
-        link_config *link;
+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;
 
-        LIST_FOREACH(links, link, ctx->links) {
-                if (!match_config(link, device)) {
-                        log_info("Config file %s does not apply to device %s", link->filename, udev_device_get_sysname(device));
-                } else {
-                        log_info("Config file %s applies to device %s", link->filename, udev_device_get_sysname(device));
-                        *ret = link;
-                        return 0;
+        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;
+                     !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;
+                        }
                 }
         }
 
-        return -ENOENT;
+        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)
+                                        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;
+        }
+
+        *name = new_name;
+
+        return 0;
 }
 
-int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_device *device) {
+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;
 
-        log_info("Configuring %s", name);
-
-        if (config->description) {
-                r = udev_device_set_sysattr_value(device, "ifalias", config->description);
-                if (r < 0)
-                        log_warning("Could not set description of %s to '%s': %s", name, config->description, strerror(-r));
-                else
-                        log_info("Set link description of %s to '%s'", name, config->description);
-        }
+        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");