#include <arpa/inet.h>
#include <netpacket/packet.h>
+#include <netinet/if_ether.h>
#include <net/ethernet.h>
-#include <net/if_arp.h>
#include <linux/if.h>
#include <linux/filter.h>
#include "gdhcp.h"
#include "common.h"
+#include "ipv4ll.h"
#define DISCOVER_TIMEOUT 3
-#define DISCOVER_RETRIES 5
+#define DISCOVER_RETRIES 10
#define REQUEST_TIMEOUT 3
#define REQUEST_RETRIES 5
L_NONE,
L2,
L3,
+ L_ARP,
} ListenMode;
typedef enum _dhcp_client_state {
RENEWING,
REBINDING,
RELEASED,
+ IPV4LL_PROBE,
+ IPV4LL_ANNOUNCE,
+ IPV4LL_MONITOR,
+ IPV4LL_DEFEND,
} ClientState;
struct _GDHCPClient {
int listener_sockfd;
uint8_t retry_times;
uint8_t ack_retry_times;
+ uint8_t conflicts;
guint timeout;
guint listener_watch;
GIOChannel *listener_channel;
GHashTable *send_value_hash;
GDHCPClientEventFunc lease_available_cb;
gpointer lease_available_data;
+ GDHCPClientEventFunc ipv4ll_available_cb;
+ gpointer ipv4ll_available_data;
GDHCPClientEventFunc no_lease_cb;
gpointer no_lease_data;
GDHCPClientEventFunc lease_lost_cb;
gpointer lease_lost_data;
+ GDHCPClientEventFunc ipv4ll_lost_cb;
+ gpointer ipv4ll_lost_data;
GDHCPClientEventFunc address_conflict_cb;
gpointer address_conflict_data;
GDHCPDebugFunc debug_func;
server, SERVER_PORT);
}
-static gboolean interface_is_up(int index)
+static gboolean ipv4ll_probe_timeout(gpointer dhcp_data);
+static int switch_listening_mode(GDHCPClient *dhcp_client,
+ ListenMode listen_mode);
+
+static gboolean send_probe_packet(gpointer dhcp_data)
{
- int sk, err;
- struct ifreq ifr;
- gboolean ret = FALSE;
+ GDHCPClient *dhcp_client;
+ guint timeout;
- sk = socket(PF_INET, SOCK_DGRAM, 0);
- if (sk < 0) {
- perror("Open socket error");
- return FALSE;
+ dhcp_client = dhcp_data;
+ /* if requested_ip is not valid, pick a new address*/
+ if (dhcp_client->requested_ip == 0) {
+ debug(dhcp_client, "pick a new random address");
+ dhcp_client->requested_ip = ipv4ll_random_ip(0);
}
- memset(&ifr, 0, sizeof(ifr));
- ifr.ifr_ifindex = index;
+ debug(dhcp_client, "sending IPV4LL probe request");
- err = ioctl(sk, SIOCGIFNAME, &ifr);
- if (err < 0) {
- perror("Get interface name error");
- goto done;
- }
-
- err = ioctl(sk, SIOCGIFFLAGS, &ifr);
- if (err < 0) {
- perror("Get interface flags error");
- goto done;
+ if (dhcp_client->retry_times == 1) {
+ dhcp_client->state = IPV4LL_PROBE;
+ switch_listening_mode(dhcp_client, L_ARP);
}
-
- if (ifr.ifr_flags & IFF_UP)
- ret = TRUE;
-
-done:
- close(sk);
-
- return ret;
+ ipv4ll_send_arp_packet(dhcp_client->mac_address, 0,
+ dhcp_client->requested_ip, dhcp_client->ifindex);
+
+ if (dhcp_client->retry_times < PROBE_NUM) {
+ /*add a random timeout in range of PROBE_MIN to PROBE_MAX*/
+ timeout = ipv4ll_random_delay_ms(PROBE_MAX-PROBE_MIN);
+ timeout += PROBE_MIN*1000;
+ } else
+ timeout = (ANNOUNCE_WAIT * 1000);
+
+ dhcp_client->timeout = g_timeout_add_full(G_PRIORITY_HIGH,
+ timeout,
+ ipv4ll_probe_timeout,
+ dhcp_client,
+ NULL);
+ return FALSE;
}
-static char *get_interface_name(int index)
-{
- struct ifreq ifr;
- int sk, err;
+static gboolean ipv4ll_announce_timeout(gpointer dhcp_data);
+static gboolean ipv4ll_defend_timeout(gpointer dhcp_data);
- if (index < 0)
- return NULL;
+static gboolean send_announce_packet(gpointer dhcp_data)
+{
+ GDHCPClient *dhcp_client;
- sk = socket(PF_INET, SOCK_DGRAM, 0);
- if (sk < 0) {
- perror("Open socket error");
- return NULL;
- }
+ dhcp_client = dhcp_data;
- memset(&ifr, 0, sizeof(ifr));
- ifr.ifr_ifindex = index;
+ debug(dhcp_client, "sending IPV4LL announce request");
- err = ioctl(sk, SIOCGIFNAME, &ifr);
- if (err < 0) {
- perror("Get interface name error");
- close(sk);
- return NULL;
- }
+ ipv4ll_send_arp_packet(dhcp_client->mac_address,
+ dhcp_client->requested_ip,
+ dhcp_client->requested_ip,
+ dhcp_client->ifindex);
- close(sk);
+ if (dhcp_client->timeout > 0)
+ g_source_remove(dhcp_client->timeout);
+ dhcp_client->timeout = 0;
- return g_strdup(ifr.ifr_name);
+ if (dhcp_client->state == IPV4LL_DEFEND) {
+ dhcp_client->timeout =
+ g_timeout_add_seconds_full(G_PRIORITY_HIGH,
+ DEFEND_INTERVAL,
+ ipv4ll_defend_timeout,
+ dhcp_client,
+ NULL);
+ return TRUE;
+ } else
+ dhcp_client->timeout =
+ g_timeout_add_seconds_full(G_PRIORITY_HIGH,
+ ANNOUNCE_INTERVAL,
+ ipv4ll_announce_timeout,
+ dhcp_client,
+ NULL);
+ return TRUE;
}
static void get_interface_mac_address(int index, uint8_t *mac_address)
dhcp_client->type = type;
dhcp_client->ifindex = ifindex;
dhcp_client->lease_available_cb = NULL;
+ dhcp_client->ipv4ll_available_cb = NULL;
dhcp_client->no_lease_cb = NULL;
dhcp_client->lease_lost_cb = NULL;
+ dhcp_client->ipv4ll_lost_cb = NULL;
dhcp_client->address_conflict_cb = NULL;
dhcp_client->listener_watch = 0;
dhcp_client->retry_times = 0;
setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog,
sizeof(filter_prog));
+ memset(&sock, 0, sizeof(sock));
sock.sll_family = AF_PACKET;
sock.sll_protocol = htons(ETH_P_IP);
sock.sll_ifindex = ifindex;
return bytes - (sizeof(packet.ip) + sizeof(packet.udp));
}
+static void ipv4ll_start(GDHCPClient *dhcp_client)
+{
+ guint timeout;
+ int seed;
+
+ if (dhcp_client->timeout > 0) {
+ g_source_remove(dhcp_client->timeout);
+ dhcp_client->timeout = 0;
+ }
+
+ switch_listening_mode(dhcp_client, L_NONE);
+ dhcp_client->type = G_DHCP_IPV4LL;
+ dhcp_client->retry_times = 0;
+ dhcp_client->requested_ip = 0;
+
+ /*try to start with a based mac address ip*/
+ seed = (dhcp_client->mac_address[4] << 8 | dhcp_client->mac_address[4]);
+ dhcp_client->requested_ip = ipv4ll_random_ip(seed);
+
+ /*first wait a random delay to avoid storm of arp request on boot*/
+ timeout = ipv4ll_random_delay_ms(PROBE_WAIT);
+
+ dhcp_client->retry_times++;
+ dhcp_client->timeout = g_timeout_add_full(G_PRIORITY_HIGH,
+ timeout,
+ send_probe_packet,
+ dhcp_client,
+ NULL);
+}
+
+static void ipv4ll_stop(GDHCPClient *dhcp_client)
+{
+
+ switch_listening_mode(dhcp_client, L_NONE);
+
+ if (dhcp_client->timeout > 0)
+ g_source_remove(dhcp_client->timeout);
+
+ if (dhcp_client->listener_watch > 0) {
+ g_source_remove(dhcp_client->listener_watch);
+ dhcp_client->listener_watch = 0;
+ }
+
+ dhcp_client->state = IPV4LL_PROBE;
+ dhcp_client->retry_times = 0;
+ dhcp_client->requested_ip = 0;
+
+ g_free(dhcp_client->assigned_ip);
+ dhcp_client->assigned_ip = NULL;
+}
+
+static int ipv4ll_recv_arp_packet(GDHCPClient *dhcp_client)
+{
+ int bytes;
+ struct ether_arp arp;
+ uint32_t ip_requested;
+ int source_conflict;
+ int target_conflict;
+
+ memset(&arp, 0, sizeof(arp));
+ bytes = 0;
+ bytes = read(dhcp_client->listener_sockfd, &arp, sizeof(arp));
+ if (bytes < 0)
+ return bytes;
+
+ if (arp.arp_op != htons(ARPOP_REPLY) &&
+ arp.arp_op != htons(ARPOP_REQUEST))
+ return -EINVAL;
+
+ ip_requested = ntohl(dhcp_client->requested_ip);
+ source_conflict = !memcmp(arp.arp_spa, &ip_requested,
+ sizeof(ip_requested));
+
+ target_conflict = !memcmp(arp.arp_tpa, &ip_requested,
+ sizeof(ip_requested));
+
+ if (!source_conflict && !target_conflict)
+ return 0;
+
+ dhcp_client->conflicts++;
+
+ debug(dhcp_client, "IPV4LL conflict detected");
+
+ if (dhcp_client->state == IPV4LL_MONITOR) {
+ if (!source_conflict)
+ return 0;
+ dhcp_client->state = IPV4LL_DEFEND;
+ debug(dhcp_client, "DEFEND mode conflicts : %d",
+ dhcp_client->conflicts);
+ /*Try to defend with a single announce*/
+ send_announce_packet(dhcp_client);
+ return 0;
+ }
+
+ if (dhcp_client->state == IPV4LL_DEFEND) {
+ if (!source_conflict)
+ return 0;
+ else if (dhcp_client->ipv4ll_lost_cb != NULL)
+ dhcp_client->ipv4ll_lost_cb(dhcp_client,
+ dhcp_client->ipv4ll_lost_data);
+ }
+
+ ipv4ll_stop(dhcp_client);
+
+ if (dhcp_client->conflicts < MAX_CONFLICTS) {
+ /*restart whole state machine*/
+ dhcp_client->retry_times++;
+ dhcp_client->timeout =
+ g_timeout_add_full(G_PRIORITY_HIGH,
+ ipv4ll_random_delay_ms(PROBE_WAIT),
+ send_probe_packet,
+ dhcp_client,
+ NULL);
+ }
+ /* Here we got a lot of conflicts, RFC3927 states that we have
+ * to wait RATE_LIMIT_INTERVAL before retrying,
+ * but we just report failure.
+ */
+ else if (dhcp_client->no_lease_cb != NULL)
+ dhcp_client->no_lease_cb(dhcp_client,
+ dhcp_client->no_lease_data);
+
+ return 0;
+}
+
static gboolean check_package_owner(GDHCPClient *dhcp_client,
struct dhcp_packet *packet)
{
else if (listen_mode == L3)
listener_sockfd = dhcp_l3_socket(CLIENT_PORT,
dhcp_client->interface);
+ else if (listen_mode == L_ARP)
+ listener_sockfd = ipv4ll_arp_socket(dhcp_client->ifindex);
else
return -EIO;
g_io_channel_set_close_on_unref(listener_channel, TRUE);
dhcp_client->listener_watch =
- g_io_add_watch_full(listener_channel,
- G_PRIORITY_HIGH, G_IO_IN,
+ g_io_add_watch_full(listener_channel, G_PRIORITY_HIGH,
+ G_IO_IN | G_IO_NVAL | G_IO_ERR | G_IO_HUP,
listener_event, dhcp_client,
NULL);
g_io_channel_unref(dhcp_client->listener_channel);
if (dhcp_client->retry_times == REQUEST_RETRIES) {
dhcp_client->state = INIT_SELECTING;
-
- if (dhcp_client->no_lease_cb != NULL)
- dhcp_client->no_lease_cb(dhcp_client,
- dhcp_client->no_lease_data);
+ ipv4ll_start(dhcp_client);
return;
}
return ret;
}
-static GList *get_option_value_list(char *value)
+static GList *get_option_value_list(char *value, GDHCPOptionType type)
{
char *pos = value;
GList *list = NULL;
if (pos == NULL)
return NULL;
+ if (type == OPTION_STRING)
+ return g_list_append(list, g_strdup(value));
+
while ((pos = strchr(pos, ' ')) != NULL) {
*pos = '\0';
g_hash_table_remove(dhcp_client->code_value_hash,
GINT_TO_POINTER((int) code));
- value_list = get_option_value_list(option_value);
+ value_list = get_option_value_list(option_value, type);
g_free(option_value);
re = dhcp_recv_l2_packet(&packet, dhcp_client->listener_sockfd);
else if (dhcp_client->listen_mode == L3)
re = dhcp_recv_l3_packet(&packet, dhcp_client->listener_sockfd);
+ else if (dhcp_client->listen_mode == L_ARP) {
+ re = ipv4ll_recv_arp_packet(dhcp_client);
+ return TRUE;
+ }
else
re = -EIO;
message_type = dhcp_get_option(&packet, DHCP_MESSAGE_TYPE);
if (message_type == NULL)
- /* No message type option, ignore pakcage */
+ /* No message type option, ignore package */
return TRUE;
debug(dhcp_client, "received DHCP packet (current state %d)",
return FALSE;
}
+static gboolean ipv4ll_defend_timeout(gpointer dhcp_data)
+{
+ GDHCPClient *dhcp_client = dhcp_data;
+
+ debug(dhcp_client, "back to MONITOR mode");
+
+ dhcp_client->conflicts = 0;
+ dhcp_client->state = IPV4LL_MONITOR;
+
+ return FALSE;
+}
+
+static gboolean ipv4ll_announce_timeout(gpointer dhcp_data)
+{
+ GDHCPClient *dhcp_client = dhcp_data;
+ uint32_t ip;
+
+ debug(dhcp_client, "request timeout (retries %d)",
+ dhcp_client->retry_times);
+
+ if (dhcp_client->retry_times != ANNOUNCE_NUM){
+ dhcp_client->retry_times++;
+ send_announce_packet(dhcp_client);
+ return FALSE;
+ }
+
+ ip = htonl(dhcp_client->requested_ip);
+ debug(dhcp_client, "switching to monitor mode");
+ dhcp_client->state = IPV4LL_MONITOR;
+ dhcp_client->assigned_ip = get_ip(ip);
+
+ if (dhcp_client->ipv4ll_available_cb != NULL)
+ dhcp_client->ipv4ll_available_cb(dhcp_client,
+ dhcp_client->ipv4ll_available_data);
+ dhcp_client->conflicts = 0;
+
+ return FALSE;
+}
+
+static gboolean ipv4ll_probe_timeout(gpointer dhcp_data)
+{
+
+ GDHCPClient *dhcp_client = dhcp_data;
+
+ debug(dhcp_client, "IPV4LL probe timeout (retries %d)",
+ dhcp_client->retry_times);
+
+ if (dhcp_client->retry_times == PROBE_NUM) {
+ dhcp_client->state = IPV4LL_ANNOUNCE;
+ dhcp_client->retry_times = 0;
+
+ dhcp_client->retry_times++;
+ send_announce_packet(dhcp_client);
+ return FALSE;
+ }
+ dhcp_client->retry_times++;
+ send_probe_packet(dhcp_client);
+
+ return FALSE;
+}
+
int g_dhcp_client_start(GDHCPClient *dhcp_client)
{
int re;
if (dhcp_client->retry_times == DISCOVER_RETRIES) {
- if (dhcp_client->no_lease_cb != NULL)
- dhcp_client->no_lease_cb(dhcp_client,
- dhcp_client->no_lease_data);
-
+ ipv4ll_start(dhcp_client);
return 0;
}
dhcp_client->lease_available_cb = func;
dhcp_client->lease_available_data = data;
return;
+ case G_DHCP_CLIENT_EVENT_IPV4LL_AVAILABLE:
+ dhcp_client->ipv4ll_available_cb = func;
+ dhcp_client->ipv4ll_available_data = data;
+ return;
case G_DHCP_CLIENT_EVENT_NO_LEASE:
dhcp_client->no_lease_cb = func;
dhcp_client->no_lease_data = data;
dhcp_client->lease_lost_cb = func;
dhcp_client->lease_lost_data = data;
return;
+ case G_DHCP_CLIENT_EVENT_IPV4LL_LOST:
+ dhcp_client->ipv4ll_lost_cb = func;
+ dhcp_client->ipv4ll_lost_data = data;
+ return;
case G_DHCP_CLIENT_EVENT_ADDRESS_CONFLICT:
dhcp_client->address_conflict_cb = func;
dhcp_client->address_conflict_data = data;