From af6f0d422c521374ee6a2dd92df5935a5a476ae5 Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Sat, 26 Oct 2013 00:34:01 +0200 Subject: udev: add network link configuration tool This tool applies hardware specific settings to network devices before they are announced via libudev. Settings that will probably eventually be supported are MTU, Speed, DuplexMode, WakeOnLan, MACAddress, MACAddressPolicy (e.g., 'hardware', 'synthetic' or 'random'), Name and NamePolicy (replacing our current interface naming logic). This patch only introduces support for Description, as a proof of concept. Some of these settings may later be overriden by a network management daemon/script. However, these tools should always listen and wait on libudev before touching a device (listening on netlink is not enough). This is no different from how things used to be, as we always supported changing the network interface name from udev rules, which does not work if someone has already started using it. The tool is configured by .link files in /etc/net/links/ (with the usual overriding logic in /run and /lib). The first (in lexicographical order) matching .link file is applied to a given device, and all others are ignored. The .link files contain a [Match] section with (currently) the keys MACAddress, Driver, Type (see DEVTYPE in udevadm info) and Path (this matches on the stable device path as exposed as ID_PATH, and not the unstable DEVPATH). A .link file matches a given device if all of the specified keys do. Currently the keys are treated as plain strings, but some limited globbing may later be added to the keys where it makes sense. Example: /etc/net/links/50-wireless.link [Match] MACAddress=98:f2:e4:42:c6:92 Path=pci-0000:02:00.0-bcma-0 Type=wlan [Link] Description=The wireless link --- src/udev/net/.gitignore | 1 + src/udev/net/Makefile | 1 + src/udev/net/link-config-gperf.gperf | 21 +++ src/udev/net/link-config.c | 244 +++++++++++++++++++++++++++++++++++ src/udev/net/link-config.h | 55 ++++++++ src/udev/udev-builtin-net_link.c | 96 ++++++++++++++ src/udev/udev-builtin.c | 1 + src/udev/udev.h | 2 + 8 files changed, 421 insertions(+) create mode 100644 src/udev/net/.gitignore create mode 120000 src/udev/net/Makefile create mode 100644 src/udev/net/link-config-gperf.gperf create mode 100644 src/udev/net/link-config.c create mode 100644 src/udev/net/link-config.h create mode 100644 src/udev/udev-builtin-net_link.c (limited to 'src/udev') diff --git a/src/udev/net/.gitignore b/src/udev/net/.gitignore new file mode 100644 index 0000000000..9ca85bacc9 --- /dev/null +++ b/src/udev/net/.gitignore @@ -0,0 +1 @@ +/link-config-gperf.c diff --git a/src/udev/net/Makefile b/src/udev/net/Makefile new file mode 120000 index 0000000000..94aaae2c4d --- /dev/null +++ b/src/udev/net/Makefile @@ -0,0 +1 @@ +../../Makefile \ No newline at end of file diff --git a/src/udev/net/link-config-gperf.gperf b/src/udev/net/link-config-gperf.gperf new file mode 100644 index 0000000000..c567e6dfaa --- /dev/null +++ b/src/udev/net/link-config-gperf.gperf @@ -0,0 +1,21 @@ +%{ +#include +#include "conf-parser.h" +#include "link-config.h" +%} +struct ConfigPerfItem; +%null_strings +%language=ANSI-C +%define slot-name section_and_lvalue +%define hash-function-name link_config_gperf_hash +%define lookup-function-name link_config_gperf_lookup +%readonly-tables +%omit-struct-type +%struct-type +%includes +%% +Match.MACAddress, config_parse_string, 0, offsetof(link_config, match_mac) +Match.Path, config_parse_string, 0, offsetof(link_config, match_path) +Match.Driver, config_parse_string, 0, offsetof(link_config, match_driver) +Match.Type, config_parse_string, 0, offsetof(link_config, match_type) +Link.Description, config_parse_string, 0, offsetof(link_config, description) diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c new file mode 100644 index 0000000000..7686d87f80 --- /dev/null +++ b/src/udev/net/link-config.c @@ -0,0 +1,244 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright (C) 2013 Tom Gundersen + + 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 . +***/ + +#include "link-config.h" + +#include "util.h" +#include "log.h" +#include "strv.h" +#include "path-util.h" +#include "conf-parser.h" +#include "conf-files.h" + +struct link_config_ctx { + LIST_HEAD(link_config, links); + + char **link_dirs; + usec_t *link_dirs_ts_usec; +}; + +int link_config_ctx_new(link_config_ctx **ret) { + link_config_ctx *ctx; + + if (!ret) + return -EINVAL; + + ctx = new0(link_config_ctx, 1); + if (!ctx) + return -ENOMEM; + + 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->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; + } + + *ret = ctx; + 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); + } +} + +void link_config_ctx_free(link_config_ctx *ctx) { + if (!ctx) + return; + + strv_free(ctx->link_dirs); + free(ctx->link_dirs_ts_usec); + link_configs_free(ctx); + + free(ctx); + + return; +} + +static int load_link(link_config_ctx *ctx, const char *filename) { + link_config *link; + FILE *file; + int r; + + 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; + } + + 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->filename = strdup(filename); + + LIST_PREPEND(links, ctx->links, link); + + return 0; + +failure: + free(link); + return r; +} + +int link_config_load(link_config_ctx *ctx) { + int r; + char **files, **f; + + link_configs_free(ctx); + + /* update timestamps */ + paths_check_timestamp(ctx->link_dirs, ctx->link_dirs_ts_usec, true); + + r = conf_files_list_strv(&files, ".link", NULL, (const char **)ctx->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(ctx->link_dirs, ctx->link_dirs_ts_usec, false); +} + +static bool match_config(link_config *match, struct udev_device *device) { + const char *property; + + 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); + 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; + } + } + + 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; + } + } + + 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; + } + } + + return 1; +} + +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 (!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; + } + } + + return -ENOENT; +} + +int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_device *device) { + const char *name; + int 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); + } + + return 0; +} diff --git a/src/udev/net/link-config.h b/src/udev/net/link-config.h new file mode 100644 index 0000000000..da5608ce4c --- /dev/null +++ b/src/udev/net/link-config.h @@ -0,0 +1,55 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright (C) 2013 Tom Gundersen + + 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 . +***/ + +#pragma once + +#include "libudev.h" +#include "util.h" +#include "list.h" + + +typedef struct link_config_ctx link_config_ctx; +typedef struct link_config link_config; + +struct link_config { + char *filename; + + char *match_mac; + char *match_path; + char *match_driver; + char *match_type; + + char *description; + + LIST_FIELDS(link_config, links); +}; + +int link_config_ctx_new(link_config_ctx **ret); +void link_config_ctx_free(link_config_ctx *ctx); + +int link_config_load(link_config_ctx *ctx); +bool link_config_should_reload(link_config_ctx *ctx); + +int link_config_get(link_config_ctx *ctx, struct udev_device *device, struct link_config **ret); +int link_config_apply(link_config_ctx *ctx, struct link_config *config, struct udev_device *device); + +/* gperf lookup function */ +const struct ConfigPerfItem* link_config_gperf_lookup(const char *key, unsigned length); diff --git a/src/udev/udev-builtin-net_link.c b/src/udev/udev-builtin-net_link.c new file mode 100644 index 0000000000..d7cbe6a016 --- /dev/null +++ b/src/udev/udev-builtin-net_link.c @@ -0,0 +1,96 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2013 Tom Gundersen + + 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 . +***/ + +#include "link-config.h" +#include "udev.h" +#include "log.h" + +link_config_ctx *ctx; + +static int builtin_net_link(struct udev_device *dev, int argc, char **argv, bool test) { + link_config *link; + int r; + + if (argc > 1) { + log_error("This program takes no arguments."); + return EXIT_FAILURE; + } + + r = link_config_get(ctx, dev, &link); + if (r < 0) { + if (r == -ENOENT) { + log_info("No matching link configuration found"); + return EXIT_SUCCESS; + } else { + log_error("Could not get link config"); + return EXIT_FAILURE; + } + } + + r = link_config_apply(ctx, link, dev); + if (r < 0) { + log_error("Could not apply link config"); + return EXIT_FAILURE; + } + + return EXIT_SUCCESS; +} + +static int builtin_net_link_init(struct udev *udev) { + int r; + + if (ctx) + return 0; + + r = link_config_ctx_new(&ctx); + if (r < 0) + return r; + + r = link_config_load(ctx); + if (r < 0) + return r; + + log_debug("Created link configuration context"); + return 0; +} + +static void builtin_net_link_exit(struct udev *udev) { + link_config_ctx_free(ctx); + log_debug("Unloaded link configuration context"); +} + +static bool builtin_net_link_validate(struct udev *udev) { + log_debug("Check if link configuration needs reloading"); + if (!ctx) + return false; + + return link_config_should_reload(ctx); +} + +const struct udev_builtin udev_builtin_net_link = { + .name = "net_link", + .cmd = builtin_net_link, + .init = builtin_net_link_init, + .exit = builtin_net_link_exit, + .validate = builtin_net_link_validate, + .help = "configure network link", + .run_once = false, +}; diff --git a/src/udev/udev-builtin.c b/src/udev/udev-builtin.c index 6b3a518c2e..85901e8ee3 100644 --- a/src/udev/udev-builtin.c +++ b/src/udev/udev-builtin.c @@ -44,6 +44,7 @@ static const struct udev_builtin *builtins[] = { [UDEV_BUILTIN_KMOD] = &udev_builtin_kmod, #endif [UDEV_BUILTIN_NET_ID] = &udev_builtin_net_id, + [UDEV_BUILTIN_NET_LINK] = &udev_builtin_net_link, [UDEV_BUILTIN_PATH_ID] = &udev_builtin_path_id, [UDEV_BUILTIN_USB_ID] = &udev_builtin_usb_id, #ifdef HAVE_ACL diff --git a/src/udev/udev.h b/src/udev/udev.h index 29e96d637e..7cca8b8c83 100644 --- a/src/udev/udev.h +++ b/src/udev/udev.h @@ -153,6 +153,7 @@ enum udev_builtin_cmd { UDEV_BUILTIN_KMOD, #endif UDEV_BUILTIN_NET_ID, + UDEV_BUILTIN_NET_LINK, UDEV_BUILTIN_PATH_ID, UDEV_BUILTIN_USB_ID, #ifdef HAVE_ACL @@ -183,6 +184,7 @@ extern const struct udev_builtin udev_builtin_keyboard; extern const struct udev_builtin udev_builtin_kmod; #endif extern const struct udev_builtin udev_builtin_net_id; +extern const struct udev_builtin udev_builtin_net_link; extern const struct udev_builtin udev_builtin_path_id; extern const struct udev_builtin udev_builtin_usb_id; extern const struct udev_builtin udev_builtin_uaccess; -- cgit v1.2.3-54-g00ecf