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Move dhcp state handling code out of netlink.c and into state.c. netlink.c

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now just calls hooks exposed by state.c, just like the dhcp packet,
poll timeout, and signal code.

Make ifchange_deconfig() idempotent.
This commit is contained in:
Nicholas J. Kain 2011-07-04 22:10:14 -04:00
parent 88804e0102
commit 4453391154
4 changed files with 79 additions and 77 deletions
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10
ndhc/ifchange.c
View File

@ -1,5 +1,5 @@
/* ifchange.c - functions to call the interface change daemon
* Time-stamp: <2011-07-04 21:35:02 njk>
* Time-stamp: <2011-07-04 22:03:35 njk>
*
* (c) 2004-2011 Nicholas J. Kain <njkain at gmail dot com>
*
@ -39,7 +39,8 @@
#include "io.h"
#include "ifchange.h"
static struct dhcpmsg cfg_packet;
static int cfg_deconfig; // Set if the interface has already been deconfigured.
static struct dhcpmsg cfg_packet; // Copy of the current configuration packet.
// Fill buf with the ifchd command text of option 'option'.
// Returns 0 if successful, -1 if nothing was filled in.
@ -162,6 +163,9 @@ void ifchange_deconfig(void)
int sockfd;
char buf[256];
if (cfg_deconfig)
return;
sockfd = open_ifch();
snprintf(buf, sizeof buf, "interface:%s:", client_config.interface);
@ -170,6 +174,7 @@ void ifchange_deconfig(void)
snprintf(buf, sizeof buf, "ip:0.0.0.0:");
sockwrite(sockfd, buf, strlen(buf));
cfg_deconfig = 1;
memset(&cfg_packet, 0, sizeof cfg_packet);
close(sockfd);
@ -223,6 +228,7 @@ void ifchange_bind(struct dhcpmsg *packet)
send_cmd(sockfd, packet, DHCP_BROADCAST);
send_cmd(sockfd, packet, DHCP_WINS_SERVER);
cfg_deconfig = 0;
memcpy(&cfg_packet, packet, sizeof cfg_packet);
close(sockfd);

57
ndhc/netlink.c
View File

@ -21,48 +21,21 @@
#include <assert.h>
#include <asm/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <net/if.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <string.h>
#include <sys/select.h>
#include <fcntl.h>
#include <time.h>
#include <errno.h>
#include <poll.h>
#include "netlink.h"
#include "ifchange.h"
#include "arp.h"
#include "log.h"
#include "nl.h"
#include "state.h"
static char nlbuf[8192];
int nlportid;
static void restart_if(struct client_state_t *cs)
{
log_line("nl: %s back, querying for new lease", client_config.interface);
// XXX: Same as packet.c - merge somehow?
ifchange_deconfig();
cs->dhcpState = DS_SELECTING;
cs->timeout = 0;
cs->clientAddr = 0;
cs->packetNum = 0;
set_listen_raw(cs);
}
static void sleep_if(struct client_state_t *cs)
{
arp_close_fd(cs);
set_listen_none(cs);
cs->dhcpState = DS_RELEASED;
cs->timeout = -1;
}
static int nlrtattr_assign(struct nlattr *attr, int type, void *data)
{
struct nlattr **tb = data;
@ -114,33 +87,17 @@ static int nl_process_msgs(const struct nlmsghdr *nlh, void *data)
if (ifm->ifi_flags & IFF_RUNNING) {
if (cs->ifsPrevState != IFS_UP) {
cs->ifsPrevState = IFS_UP;
// If we have a lease, then check to see
// if our gateway is still valid (via ARP).
// If it fails, state -> SELECTING.
if (cs->dhcpState == DS_BOUND) {
if (arp_gw_check(cs) == -1)
log_warning("nl: arp_gw_check could not make arp socket, assuming lease is still OK");
else
log_line("nl: interface back, revalidating lease");
// If we don't have a lease, state -> SELECTING.
} else if (cs->dhcpState != DS_SELECTING)
restart_if(cs);
ifup_action(cs);
}
} else {
// No hardware carrier.
if (cs->ifsPrevState != IFS_DOWN) {
log_line("Interface carrier down. Going to sleep.");
} else if (cs->ifsPrevState != IFS_DOWN) {
// Interface configured, but no hardware carrier.
cs->ifsPrevState = IFS_DOWN;
sleep_if(cs);
ifnocarrier_action(cs);
}
}
} else {
} else if (cs->ifsPrevState != IFS_SHUT) {
// User shut down the interface.
if (cs->ifsPrevState != IFS_SHUT) {
log_line("Interface shut down. Going to sleep.");
cs->ifsPrevState = IFS_SHUT;
sleep_if(cs);
}
ifdown_action(cs);
}
break;
case RTM_DELLINK:

80
ndhc/state.c
View File

@ -56,6 +56,17 @@ static int delay_timeout(int numpackets)
return to * 1000;
}
static void reinit_selecting(struct client_state_t *cs, int timeout)
{
ifchange_deconfig();
cs->dhcpState = DS_SELECTING;
cs->timeout = timeout;
cs->clientAddr = 0;
cs->packetNum = 0;
set_listen_raw(cs);
}
// Triggered after a DHCP lease request packet has been sent and no reply has
// been received within the response wait time. If we've not exceeded the
// maximum number of request retransmits, then send another packet and wait
@ -66,12 +77,8 @@ static void requesting_timeout(struct client_state_t *cs)
send_selecting(cs);
cs->timeout = delay_timeout(cs->packetNum);
cs->packetNum++;
} else {
cs->dhcpState = DS_SELECTING;
cs->timeout = 0;
cs->packetNum = 0;
set_listen_raw(cs);
}
} else
reinit_selecting(cs, 0);
}
// Triggered when the lease has been held for a significant fraction of its
@ -86,12 +93,8 @@ static void bound_timeout(struct client_state_t *cs)
static void lease_timedout(struct client_state_t *cs)
{
cs->dhcpState = DS_SELECTING;
log_line("Lease lost, entering init state.");
ifchange_deconfig();
cs->timeout = 0;
cs->packetNum = 0;
set_listen_raw(cs);
reinit_selecting(cs, 0);
}
// Triggered when a DHCP renew request has been sent and no reply has been
@ -173,22 +176,12 @@ static void an_packet(struct client_state_t *cs, struct dhcpmsg *packet,
// Can transition from DS_ARP_CHECK to DS_BOUND or DS_SELECTING.
if (arp_check(cs, packet) == -1) {
log_warning("arp_check failed to make arp socket, retrying lease");
ifchange_deconfig();
cs->dhcpState = DS_SELECTING;
cs->timeout = 30000;
cs->clientAddr = 0;
cs->packetNum = 0;
set_listen_raw(cs);
reinit_selecting(cs, 3000);
}
} else if (*message == DHCPNAK) {
log_line("Received DHCP NAK.");
ifchange_deconfig();
cs->dhcpState = DS_SELECTING;
cs->timeout = 3000;
cs->clientAddr = 0;
cs->packetNum = 0;
set_listen_raw(cs);
reinit_selecting(cs, 3000);
}
}
@ -289,6 +282,47 @@ static void frenew(struct client_state_t *cs)
cs->timeout = 0;
}
static void restart_if(struct client_state_t *cs)
{
log_line("nl: %s back, querying for new lease", client_config.interface);
reinit_selecting(cs, 0);
}
static void sleep_if(struct client_state_t *cs)
{
arp_close_fd(cs);
set_listen_none(cs);
cs->dhcpState = DS_RELEASED;
cs->timeout = -1;
}
void ifup_action(struct client_state_t *cs)
{
// If we have a lease, then check to see
// if our gateway is still valid (via ARP).
// If it fails, state -> SELECTING.
if (cs->dhcpState == DS_BOUND) {
if (arp_gw_check(cs) == -1)
log_warning("nl: arp_gw_check could not make arp socket, assuming lease is still OK");
else
log_line("nl: interface back, revalidating lease");
// If we don't have a lease, state -> SELECTING.
} else if (cs->dhcpState != DS_SELECTING)
restart_if(cs);
}
void ifdown_action(struct client_state_t *cs)
{
log_line("Interface shut down. Going to sleep.");
sleep_if(cs);
}
void ifnocarrier_action(struct client_state_t *cs)
{
log_line("Interface carrier down. Going to sleep.");
sleep_if(cs);
}
void packet_action(struct client_state_t *cs, struct dhcpmsg *packet,
uint8_t *message)
{

5
ndhc/state.h
View File

@ -21,5 +21,10 @@ void packet_action(struct client_state_t *cs, struct dhcpmsg *packet,
void timeout_action(struct client_state_t *cs);
void force_renew_action(struct client_state_t *cs);
void force_release_action(struct client_state_t *cs);
void ifup_action(struct client_state_t *cs);
void ifnocarrier_action(struct client_state_t *cs);
void ifdown_action(struct client_state_t *cs);
#endif