--- /dev/null
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <linux/if.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include <log/log.h>
+#include <list/list.h>
+#include <talloc/talloc.h>
+#include <waiter/waiter.h>
+#include <pb-config/pb-config.h>
+#include <system/system.h>
+
+#include "network.h"
+
+#define HWADDR_SIZE 6
+#define PIDFILE_BASE (LOCAL_STATE_DIR "/petitboot/")
+
+#define for_each_nlmsg(buf, nlmsg, len) \
+ for (nlmsg = (struct nlmsghdr *)buf; \
+ NLMSG_OK(nlmsg, len) && nlmsg->nlmsg_type != NLMSG_DONE; \
+ nlmsg = NLMSG_NEXT(nlmsg, len))
+
+#define for_each_rta(buf, rta, attrlen) \
+ for (rta = (struct rtattr *)(buf); RTA_OK(rta, attrlen); \
+ rta = RTA_NEXT(rta, attrlen))
+
+
+struct interface {
+ int ifindex;
+ char name[IFNAMSIZ];
+ uint8_t hwaddr[HWADDR_SIZE];
+
+ enum {
+ IFSTATE_NEW,
+ IFSTATE_UP_WAITING_LINK,
+ IFSTATE_CONFIGURED,
+ IFSTATE_IGNORED,
+ } state;
+
+ struct list_item list;
+};
+
+struct network {
+ struct list interfaces;
+ struct waiter *waiter;
+ int netlink_sd;
+ bool manual_config;
+ bool dry_run;
+};
+
+static const struct network_config *find_config_by_hwaddr(
+ uint8_t *hwaddr)
+{
+ const struct config *config;
+ int i;
+
+ config = config_get();
+ if (!config)
+ return NULL;
+
+ for (i = 0; i < config->n_network_configs; i++) {
+ struct network_config *netconf = config->network_configs[i];
+
+ if (!memcmp(netconf->hwaddr, hwaddr, HWADDR_SIZE))
+ return netconf;
+ }
+
+ return NULL;
+}
+
+static struct interface *find_interface_by_ifindex(struct network *network,
+ int ifindex)
+{
+ struct interface *interface;
+
+ list_for_each_entry(&network->interfaces, interface, list)
+ if (interface->ifindex == ifindex)
+ return interface;
+
+ return NULL;
+}
+
+static int network_init_netlink(struct network *network)
+{
+ struct sockaddr_nl addr;
+ int rc;
+
+ memset(&addr, 0, sizeof(addr));
+ addr.nl_family = AF_NETLINK;
+ addr.nl_groups = RTMGRP_LINK;
+
+ network->netlink_sd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
+ if (network->netlink_sd < 0) {
+ perror("socket(AF_NETLINK)");
+ return -1;
+ }
+
+ rc = bind(network->netlink_sd, (struct sockaddr *)&addr, sizeof(addr));
+ if (rc) {
+ perror("bind(sockaddr_nl)");
+ close(network->netlink_sd);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int network_send_link_query(struct network *network)
+{
+ int rc;
+ struct {
+ struct nlmsghdr nlmsg;
+ struct rtgenmsg rtmsg;
+ } msg;
+
+ memset(&msg, 0, sizeof(msg));
+
+ msg.nlmsg.nlmsg_len = sizeof(msg);
+ msg.nlmsg.nlmsg_type = RTM_GETLINK;
+ msg.nlmsg.nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT;
+ msg.nlmsg.nlmsg_seq = 0;
+ msg.nlmsg.nlmsg_pid = 0;
+ msg.rtmsg.rtgen_family = AF_UNSPEC;
+
+ rc = send(network->netlink_sd, &msg, sizeof(msg), MSG_NOSIGNAL);
+ if (rc != sizeof(msg))
+ return -1;
+
+ return 0;
+}
+
+static int interface_up(struct network *network, struct interface *interface)
+{
+ int rc;
+ const char *argv[] = {
+ pb_system_apps.ip,
+ "link",
+ "set",
+ interface->name,
+ "up",
+ NULL,
+ };
+
+ rc = pb_run_cmd(argv, 1, network->dry_run);
+ if (rc) {
+ pb_log("failed to bring interface %s up\n", interface->name);
+ return -1;
+ }
+ return 0;
+}
+
+static void configure_interface_dhcp(struct network *network,
+ struct interface *interface)
+{
+ char pidfile[256];
+ const char *argv[] = {
+ pb_system_apps.udhcpc,
+ "-R",
+ "-n",
+ "-p", pidfile,
+ "-i", interface->name,
+ NULL,
+ };
+ snprintf(pidfile, sizeof(pidfile), "%s/udhcpc-%s.pid",
+ PIDFILE_BASE, interface->name);
+
+ pb_run_cmd(argv, 0, network->dry_run);
+ return;
+}
+
+static void configure_interface_static(struct network *network,
+ struct interface *interface,
+ const struct network_config *config)
+{
+ const char *addr_argv[] = {
+ pb_system_apps.ip,
+ "address",
+ "add",
+ config->static_config.address,
+ "dev",
+ interface->name,
+ NULL,
+ };
+ const char *route_argv[] = {
+ pb_system_apps.ip,
+ "route",
+ "add",
+ "default",
+ "via",
+ config->static_config.gateway,
+ NULL,
+ };
+ int rc;
+
+
+ rc = pb_run_cmd(addr_argv, 1, network->dry_run);
+ if (rc) {
+ pb_log("failed to add address %s to interface %s\n",
+ config->static_config.address,
+ interface->name);
+ return;
+ }
+
+ /* we need the interface up before we can route through it */
+ rc = interface_up(network, interface);
+ if (rc)
+ return;
+
+ if (config->static_config.gateway)
+ rc = pb_run_cmd(route_argv, 1, network->dry_run);
+
+ if (rc) {
+ pb_log("failed to add default route %s on interface %s\n",
+ config->static_config.gateway,
+ interface->name);
+ }
+
+ return;
+}
+
+static void configure_interface(struct network *network,
+ struct interface *interface, bool up, bool link)
+{
+ const struct network_config *config = NULL;
+
+ if (interface->state == IFSTATE_IGNORED)
+ return;
+
+ /* old interface? check that we're still up and running */
+ if (interface->state == IFSTATE_CONFIGURED) {
+ if (!up)
+ interface->state = IFSTATE_NEW;
+ else if (!link)
+ interface->state = IFSTATE_UP_WAITING_LINK;
+ else
+ return;
+ }
+
+ /* always up the lookback, no other handling required */
+ if (!strcmp(interface->name, "lo")) {
+ if (interface->state == IFSTATE_NEW)
+ interface_up(network, interface);
+ interface->state = IFSTATE_CONFIGURED;
+ return;
+ }
+
+ config = find_config_by_hwaddr(interface->hwaddr);
+ if (config && config->ignore) {
+ pb_log("network: ignoring interface %s\n", interface->name);
+ interface->state = IFSTATE_IGNORED;
+ return;
+ }
+
+ /* if we're in manual config mode, we need an interface configuration */
+ if (network->manual_config && !config) {
+ interface->state = IFSTATE_IGNORED;
+ pb_log("network: skipping %s: manual config mode, "
+ "but no config for this interface\n",
+ interface->name);
+ return;
+ }
+
+ /* new interface? bring up to the point so we can detect a link */
+ if (interface->state == IFSTATE_NEW) {
+ if (!up) {
+ interface_up(network, interface);
+ pb_log("network: bringing up interface %s\n",
+ interface->name);
+ return;
+
+ } else if (!link) {
+ interface->state = IFSTATE_UP_WAITING_LINK;
+ }
+ }
+
+ /* no link? wait for a notification */
+ if (interface->state == IFSTATE_UP_WAITING_LINK && !link)
+ return;
+
+ pb_log("network: configuring interface %s\n", interface->name);
+
+ if (!config || config->method == CONFIG_METHOD_DHCP) {
+ configure_interface_dhcp(network, interface);
+
+ } else if (config->method == CONFIG_METHOD_STATIC) {
+ configure_interface_static(network, interface, config);
+ }
+}
+
+static int network_handle_nlmsg(struct network *network, struct nlmsghdr *nlmsg)
+{
+ bool have_ifaddr, have_ifname;
+ struct interface *interface;
+ struct ifinfomsg *info;
+ struct rtattr *attr;
+ uint8_t ifaddr[6];
+ char ifname[IFNAMSIZ+1];
+ int attrlen, type;
+
+
+ /* we're only interested in NEWLINK messages */
+ type = nlmsg->nlmsg_type;
+ if (!(type == RTM_NEWLINK || type == RTM_DELLINK))
+ return 0;
+
+ info = NLMSG_DATA(nlmsg);
+
+ have_ifaddr = have_ifname = false;
+
+ attrlen = nlmsg->nlmsg_len - sizeof(*info);
+
+ /* extract the interface name and hardware address attributes */
+ for_each_rta(info + 1, attr, attrlen) {
+ void *data = RTA_DATA(attr);
+
+ switch (attr->rta_type) {
+ case IFLA_ADDRESS:
+ memcpy(ifaddr, data, sizeof(ifaddr));
+ have_ifaddr = true;
+ break;
+
+ case IFLA_IFNAME:
+ strncpy(ifname, data, IFNAMSIZ);
+ have_ifname = true;
+ break;
+ }
+ }
+
+ if (!have_ifaddr || !have_ifname)
+ return -1;
+
+ if (type == RTM_DELLINK) {
+ interface = find_interface_by_ifindex(network, info->ifi_index);
+ if (!interface)
+ return 0;
+ pb_log("network: interface %s removed\n", interface->name);
+ list_remove(&interface->list);
+ talloc_free(interface);
+ return 0;
+ }
+
+
+ interface = find_interface_by_ifindex(network, info->ifi_index);
+ if (!interface) {
+ interface = talloc_zero(network, struct interface);
+ interface->ifindex = info->ifi_index;
+ interface->state = IFSTATE_NEW;
+ memcpy(interface->hwaddr, ifaddr, sizeof(interface->hwaddr));
+ strncpy(interface->name, ifname, sizeof(interface->name) - 1);
+ }
+
+ configure_interface(network, interface,
+ info->ifi_flags & IFF_UP,
+ info->ifi_flags & IFF_LOWER_UP);
+
+ return 0;
+}
+
+static int network_netlink_process(void *arg)
+{
+ struct network *network = arg;
+ struct nlmsghdr *nlmsg;
+ unsigned int len;
+ char buf[4096];
+ int rc;
+
+ rc = recv(network->netlink_sd, buf, sizeof(buf), 0);
+ if (rc < 0) {
+ perror("netlink recv");
+ return -1;
+ }
+
+ len = rc;
+
+ for_each_nlmsg(buf, nlmsg, len)
+ network_handle_nlmsg(network, nlmsg);
+
+ return 0;
+}
+
+struct network *network_init(void *ctx, struct waitset *waitset, bool dry_run)
+{
+ struct network *network;
+ int rc;
+
+ network = talloc(ctx, struct network);
+ list_init(&network->interfaces);
+ network->manual_config = false;
+ network->dry_run = dry_run;
+
+ rc = network_init_netlink(network);
+ if (rc)
+ goto err;
+
+ network->waiter = waiter_register_io(waitset, network->netlink_sd,
+ WAIT_IN, network_netlink_process, network);
+
+ if (!network->waiter)
+ goto err;
+
+ rc = network_send_link_query(network);
+ if (rc)
+ goto err;
+
+ return network;
+
+err:
+ network_shutdown(network);
+ return NULL;
+}
+
+
+int network_shutdown(struct network *network)
+{
+ if (network->waiter)
+ waiter_remove(network->waiter);
+
+ close(network->netlink_sd);
+ talloc_free(network);
+ return 0;
+}
projects / petitboot / commitdiff