chiark / gitweb /
networkd: manager - read fallback DNS servers from config file
[elogind.git] / src / network / networkd-manager.c
index b2cb0fab4d00cabe13b18e0e76b316baf933006b..ad36553f2b48e8979cce2d5c67cd46950a1281d2 100644 (file)
  ***/
 
 #include <resolv.h>
+#include <linux/if.h>
+#include <libkmod.h>
 
+#include "conf-parser.h"
 #include "path-util.h"
 #include "networkd.h"
+#include "network-internal.h"
 #include "libudev-private.h"
 #include "udev-util.h"
 #include "rtnl-util.h"
 #include "mkdir.h"
 #include "virt.h"
 
+#include "sd-rtnl.h"
+
 const char* const network_dirs[] = {
         "/etc/systemd/network",
         "/run/systemd/network",
@@ -70,6 +76,95 @@ static int setup_signals(Manager *m) {
         return 0;
 }
 
+static int set_fallback_dns(Manager *m, const char *string) {
+        char *word, *state;
+        size_t length;
+        int r;
+
+        assert(m);
+        assert(string);
+
+        FOREACH_WORD_QUOTED(word, length, string, state) {
+                _cleanup_address_free_ Address *address = NULL;
+                Address *tail;
+                _cleanup_free_ char *addrstr = NULL;
+
+                r = address_new_dynamic(&address);
+                if (r < 0)
+                        return r;
+
+                addrstr = strndup(word, length);
+                if (!addrstr)
+                        return -ENOMEM;
+
+                r = net_parse_inaddr(addrstr, &address->family, &address->in_addr);
+                if (r < 0) {
+                        log_debug("Ignoring invalid DNS address '%s'", addrstr);
+                        continue;
+                }
+
+                LIST_FIND_TAIL(addresses, m->fallback_dns, tail);
+                LIST_INSERT_AFTER(addresses, m->fallback_dns, tail, address);
+                address = NULL;
+        }
+
+        return 0;
+}
+
+int config_parse_dnsv(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        Manager *m = userdata;
+        Address *address;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(m);
+
+        while ((address = m->fallback_dns)) {
+                LIST_REMOVE(addresses, m->fallback_dns, address);
+                address_free(address);
+        }
+
+        set_fallback_dns(m, rvalue);
+
+        return 0;
+}
+
+static int manager_parse_config_file(Manager *m) {
+        static const char fn[] = "/etc/systemd/networkd.conf";
+        _cleanup_fclose_ FILE *f = NULL;
+        int r;
+
+        assert(m);
+
+        f = fopen(fn, "re");
+        if (!f) {
+                if (errno == ENOENT)
+                        return 0;
+
+                log_warning("Failed to open configuration file %s: %m", fn);
+                return -errno;
+        }
+
+        r = config_parse(NULL, fn, f, "Network\0", config_item_perf_lookup,
+                         (void*) networkd_gperf_lookup, false, false, m);
+        if (r < 0)
+                log_warning("Failed to parse configuration file: %s", strerror(-r));
+
+        return r;
+}
+
 int manager_new(Manager **ret) {
         _cleanup_manager_free_ Manager *m = NULL;
         int r;
@@ -78,13 +173,26 @@ int manager_new(Manager **ret) {
         if (!m)
                 return -ENOMEM;
 
+        m->state_file = strdup("/run/systemd/network/state");
+        if (!m->state_file)
+                return -ENOMEM;
+
+        r = set_fallback_dns(m, DNS_SERVERS);
+        if (r < 0)
+                return r;
+
+        r = manager_parse_config_file(m);
+        if (r < 0)
+                return r;
+
         r = sd_event_default(&m->event);
         if (r < 0)
                 return r;
 
         sd_event_set_watchdog(m->event, true);
 
-        r = sd_rtnl_open(&m->rtnl, RTMGRP_LINK | RTMGRP_IPV4_IFADDR);
+        r = sd_rtnl_open(&m->rtnl, 3, RTNLGRP_LINK, RTNLGRP_IPV4_IFADDR,
+                         RTNLGRP_IPV6_IFADDR);
         if (r < 0)
                 return r;
 
@@ -96,23 +204,23 @@ int manager_new(Manager **ret) {
         if (r < 0)
                 return r;
 
-        m->udev = udev_new();
-        if (!m->udev)
-                return -ENOMEM;
-
         /* udev does not initialize devices inside containers,
          * so we rely on them being already initialized before
          * entering the container */
-        if (detect_container(NULL) > 0) {
-                m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "kernel");
-                if (!m->udev_monitor)
+        if (detect_container(NULL) <= 0) {
+                m->udev = udev_new();
+                if (!m->udev)
                         return -ENOMEM;
-        } else {
+
                 m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev");
                 if (!m->udev_monitor)
                         return -ENOMEM;
         }
 
+        m->kmod_ctx = kmod_new(NULL, NULL);
+        if (!m->kmod_ctx)
+                return -ENOMEM;
+
         m->links = hashmap_new(uint64_hash_func, uint64_compare_func);
         if (!m->links)
                 return -ENOMEM;
@@ -133,10 +241,14 @@ void manager_free(Manager *m) {
         Network *network;
         NetDev *netdev;
         Link *link;
+        Address *address;
 
         if (!m)
                 return;
 
+        free(m->state_file);
+
+        kmod_unref(m->kmod_ctx);
         udev_monitor_unref(m->udev_monitor);
         udev_unref(m->udev);
         sd_bus_unref(m->bus);
@@ -145,15 +257,20 @@ void manager_free(Manager *m) {
         sd_event_source_unref(m->sigint_event_source);
         sd_event_unref(m->event);
 
-        while ((network = m->networks))
-                network_free(network);
+        while ((address = m->fallback_dns)) {
+                LIST_REMOVE(addresses, m->fallback_dns, address);
+                address_free(address);
+        }
 
         while ((link = hashmap_first(m->links)))
-                link_free(link);
+                link_unref(link);
         hashmap_free(m->links);
 
+        while ((network = m->networks))
+                network_free(network);
+
         while ((netdev = hashmap_first(m->netdevs)))
-                netdev_free(netdev);
+                netdev_unref(netdev);
         hashmap_free(m->netdevs);
 
         sd_rtnl_unref(m->rtnl);
@@ -182,78 +299,137 @@ bool manager_should_reload(Manager *m) {
         return paths_check_timestamp(network_dirs, &m->network_dirs_ts_usec, false);
 }
 
-static int manager_process_link(Manager *m, struct udev_device *device) {
+static int manager_udev_process_link(Manager *m, struct udev_device *device) {
         Link *link = NULL;
-        int r;
+        int r, ifindex;
 
         assert(m);
         assert(device);
 
-        link_get(m, udev_device_get_ifindex(device), &link);
+        if (!streq_ptr(udev_device_get_action(device), "add"))
+                return 0;
 
-        if (streq_ptr(udev_device_get_action(device), "remove")) {
-                log_debug("%s: link removed", udev_device_get_sysname(device));
+        ifindex = udev_device_get_ifindex(device);
+        if (ifindex <= 0) {
+                log_debug("ignoring udev ADD event for device with invalid ifindex");
+                return 0;
+        }
 
-                if (link)
-                        link_free(link);
-        } else {
-                if (link) {
-                        log_debug("%s: link already exists, ignoring",
-                                  link->ifname);
-                        return 0;
-                }
+        r = link_get(m, ifindex, &link);
+        if (r == -ENODEV)
+                return 0;
+        else if (r < 0)
+                return r;
 
-                r = link_add(m, device, &link);
-                if (r < 0) {
-                        log_error("%s: could not handle link: %s",
-                                  udev_device_get_sysname(device),
-                                  strerror(-r));
-                } else
-                        log_debug("%s: link (with ifindex %" PRIu64") added",
-                                  link->ifname, link->ifindex);
-        }
+        r = link_initialized(link, device);
+        if (r < 0)
+                return r;
 
         return 0;
 }
 
-int manager_udev_enumerate_links(Manager *m) {
-        _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
-        struct udev_list_entry *item = NULL, *first = NULL;
-        int r;
+static int manager_rtnl_process_link(sd_rtnl *rtnl, sd_rtnl_message *message, void *userdata) {
+        Manager *m = userdata;
+        Link *link = NULL;
+        NetDev *netdev = NULL;
+        uint16_t type;
+        char *name;
+        int r, ifindex;
 
+        assert(rtnl);
+        assert(message);
         assert(m);
 
-        e = udev_enumerate_new(m->udev);
-        if (!e)
-                return -ENOMEM;
+        r = sd_rtnl_message_get_type(message, &type);
+        if (r < 0) {
+                log_warning("rtnl: could not get message type");
+                return 0;
+        }
 
-        r = udev_enumerate_add_match_subsystem(e, "net");
-        if (r < 0)
-                return r;
+        r = sd_rtnl_message_link_get_ifindex(message, &ifindex);
+        if (r < 0 || ifindex <= 0) {
+                log_warning("rtnl: received link message without valid ifindex");
+                return 0;
+        } else
+                link_get(m, ifindex, &link);
 
-        /* udev does not initialize devices inside containers,
-         * so we rely on them being already initialized before
-         * entering the container */
-        if (detect_container(NULL) <= 0) {
-                r = udev_enumerate_add_match_is_initialized(e);
+        r = sd_rtnl_message_read_string(message, IFLA_IFNAME, &name);
+        if (r < 0 || !name) {
+                log_warning("rtnl: received link message without valid ifname");
+                return 0;
+        } else
+                netdev_get(m, name, &netdev);
+
+        switch (type) {
+        case RTM_NEWLINK:
+                if (!link) {
+                        /* link is new, so add it */
+                        r = link_add(m, message, &link);
+                        if (r < 0) {
+                                log_debug("could not add new link");
+                                return 0;
+                        }
+                }
+
+                if (netdev) {
+                        /* netdev exists, so make sure the ifindex matches */
+                        r = netdev_set_ifindex(netdev, message);
+                        if (r < 0) {
+                                log_debug("could not set ifindex on netdev");
+                                return 0;
+                        }
+                }
+
+                r = link_update(link, message);
                 if (r < 0)
-                        return r;
+                        return 0;
+
+                break;
+
+        case RTM_DELLINK:
+                link_drop(link);
+                netdev_drop(netdev);
+
+                break;
+
+        default:
+                assert_not_reached("Received invalid RTNL message type.");
         }
 
-        r = udev_enumerate_scan_devices(e);
+        return 1;
+}
+
+int manager_rtnl_enumerate_links(Manager *m) {
+        _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL;
+        sd_rtnl_message *link;
+        int r, k;
+
+        assert(m);
+        assert(m->rtnl);
+
+        r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
         if (r < 0)
                 return r;
 
-        first = udev_enumerate_get_list_entry(e);
-        udev_list_entry_foreach(item, first) {
-                _cleanup_udev_device_unref_ struct udev_device *d = NULL;
-                int k;
+        r = sd_rtnl_message_request_dump(req, true);
+        if (r < 0)
+                return r;
 
-                d = udev_device_new_from_syspath(m->udev, udev_list_entry_get_name(item));
-                if (!d)
-                        return -ENOMEM;
+        r = sd_rtnl_call(m->rtnl, req, 0, &reply);
+        if (r < 0)
+                return r;
 
-                k = manager_process_link(m, d);
+        for (link = reply; link; link = sd_rtnl_message_next(link)) {
+                uint16_t type;
+
+                k = sd_rtnl_message_get_type(link, &type);
+                if (k < 0)
+                        return k;
+
+                if (type != RTM_NEWLINK)
+                        continue;
+
+                k = manager_rtnl_process_link(m->rtnl, link, m);
                 if (k < 0)
                         r = k;
         }
@@ -270,13 +446,18 @@ static int manager_dispatch_link_udev(sd_event_source *source, int fd, uint32_t
         if (!device)
                 return -ENOMEM;
 
-        manager_process_link(m, device);
+        manager_udev_process_link(m, device);
         return 0;
 }
 
 int manager_udev_listen(Manager *m) {
         int r;
 
+        if (detect_container(NULL) > 0)
+                return 0;
+
+        assert(m->udev_monitor);
+
         r = udev_monitor_filter_add_match_subsystem_devtype(m->udev_monitor, "net", NULL);
         if (r < 0) {
                 log_error("Could not add udev monitor filter: %s", strerror(-r));
@@ -300,50 +481,6 @@ int manager_udev_listen(Manager *m) {
         return 0;
 }
 
-static int manager_rtnl_process_link(sd_rtnl *rtnl, sd_rtnl_message *message, void *userdata) {
-        Manager *m = userdata;
-        Link *link;
-        char *name;
-        int r, ifindex;
-
-        assert(rtnl);
-        assert(message);
-        assert(m);
-
-        r = sd_rtnl_message_link_get_ifindex(message, &ifindex);
-        if (r < 0 || ifindex <= 0) {
-                log_warning("received RTM_NEWLINK message without valid ifindex");
-                return 0;
-        }
-
-        r = sd_rtnl_message_read_string(message, IFLA_IFNAME, &name);
-        if (r < 0)
-                log_warning("received RTM_NEWLINK message without valid ifname");
-        else {
-                NetDev *netdev;
-
-                r = netdev_get(m, name, &netdev);
-                if (r >= 0)
-                        netdev_set_ifindex(netdev, message);
-        }
-
-        r = link_get(m, ifindex, &link);
-        if (r < 0) {
-                log_debug("received RTM_NEWLINK message for untracked ifindex %d", ifindex);
-                return 0;
-        }
-
-        /* only track the status of links we want to manage */
-        if (link->network) {
-                r = link_update(link, message);
-                if (r < 0)
-                        return 0;
-        } else
-                log_debug("%s: received RTM_NEWLINK message for unmanaged link", link->ifname);
-
-        return 1;
-}
-
 int manager_rtnl_listen(Manager *m) {
         int r;
 
@@ -355,6 +492,18 @@ int manager_rtnl_listen(Manager *m) {
         if (r < 0)
                 return r;
 
+        r = sd_rtnl_add_match(m->rtnl, RTM_DELLINK, &manager_rtnl_process_link, m);
+        if (r < 0)
+                return r;
+
+        r = sd_rtnl_add_match(m->rtnl, RTM_NEWADDR, &link_rtnl_process_address, m);
+        if (r < 0)
+                return r;
+
+        r = sd_rtnl_add_match(m->rtnl, RTM_DELADDR, &link_rtnl_process_address, m);
+        if (r < 0)
+                return r;
+
         return 0;
 }
 
@@ -441,15 +590,22 @@ int manager_update_resolv_conf(Manager *m) {
         HASHMAP_FOREACH(link, m->links, i) {
                 if (link->network && link->network->dns) {
                         Address *address;
-                        Iterator j;
 
-                        SET_FOREACH(address, link->network->dns, j) {
+                        LIST_FOREACH(addresses, address, link->network->dns) {
                                 append_dns(f, &address->in_addr.in,
                                            address->family, &count);
                         }
                 }
         }
 
+        if (!count) {
+                Address *address;
+
+                LIST_FOREACH(addresses, address, m->fallback_dns)
+                        append_dns(f, &address->in_addr.in,
+                                   address->family, &count);
+        }
+
         fflush(f);
 
         if (ferror(f) || rename(temp_path, "/run/systemd/network/resolv.conf") < 0) {
@@ -461,3 +617,55 @@ int manager_update_resolv_conf(Manager *m) {
 
         return 0;
 }
+
+int manager_save(Manager *m) {
+        Link *link;
+        Iterator i;
+        _cleanup_free_ char *temp_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        const char *oper_state = "unknown";
+        bool dormant = false, carrier = false;
+        int r;
+
+        assert(m);
+        assert(m->state_file);
+
+        HASHMAP_FOREACH(link, m->links, i) {
+                if (link->flags & IFF_LOOPBACK)
+                        continue;
+
+                if (link_has_carrier(link->flags, link->operstate))
+                        carrier = true;
+                else if (link->operstate == IF_OPER_DORMANT)
+                        dormant = true;
+        }
+
+        if (carrier)
+                oper_state = "carrier";
+        else if (dormant)
+                oper_state = "dormant";
+
+        r = fopen_temporary(m->state_file, &f, &temp_path);
+        if (r < 0)
+                goto finish;
+
+        fchmod(fileno(f), 0644);
+
+        fprintf(f,
+                "# This is private data. Do not parse.\n"
+                "OPER_STATE=%s\n", oper_state);
+
+        fflush(f);
+
+        if (ferror(f) || rename(temp_path, m->state_file) < 0) {
+                r = -errno;
+                unlink(m->state_file);
+                unlink(temp_path);
+        }
+
+finish:
+        if (r < 0)
+                log_error("Failed to save network state to %s: %s", m->state_file, strerror(-r));
+
+        return r;
+}