emo/ndhc
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Make the renew and rebind timeouts more strictly rfc compliant, and also

Browse Source 
take into account the possiblity of renew times being ridiculously deferred
such that the current time is within lease expiration time.
This commit is contained in:
Nicholas J. Kain 2011-06-30 02:48:58 -04:00
parent 8fffc5721f
commit 339804856b
1 changed files with 43 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
ndhc/state.c
View File

@ -75,43 +75,61 @@ static void bound_timeout(struct client_state_t *cs)
renewing_timeout(cs);
}
static void lease_timedout(struct client_state_t *cs)
{
cs->dhcpState = DS_SELECTING;
log_line("Lease lost, entering init state.");
ifchange(NULL, IFCHANGE_DECONFIG);
cs->timeout = 0;
cs->packetNum = 0;
change_listen_mode(cs, LM_RAW);
}
// Triggered when a DHCP renew request has been sent and no reply has been
// received within the response wait time. This function is also directly
// called by bound_timeout() when it is time to renew a lease before it
// expires. Check to see if the lease is still valid, and if it is, send
// a unicast DHCP renew packet. If it is not, then change to the REBINDING
// state to get a new lease.
// state to send broadcast queries.
static void renewing_timeout(struct client_state_t *cs)
{
if ((cs->rebindTime - cs->renewTime) <= (cs->lease / 14400 + 1)) {
cs->dhcpState = DS_REBINDING;
cs->timeout = (cs->rebindTime - cs->renewTime) * 1000;
log_line("Entering rebinding state.");
} else {
send_renew(cs->xid, cs->serverAddr, cs->requestedIP);
cs->renewTime = ((cs->rebindTime - cs->renewTime) >> 1) + cs->renewTime;
cs->timeout = (cs->renewTime * 1000) - (curms() - cs->leaseStartTime);
long long ct = curms();
long long rbt = cs->leaseStartTime + cs->rebindTime * 1000;
if (ct < rbt) {
long long wt = (rbt - ct) / 2;
if (wt >= 30000)
send_renew(cs->xid, cs->serverAddr, cs->requestedIP);
else
wt = rbt - ct;
cs->timeout = wt;
return;
}
long long elt = cs->leaseStartTime + cs->lease * 1000;
if (ct < elt) {
cs->dhcpState = DS_REBINDING;
cs->timeout = elt - ct / 2;
log_line("Entering rebinding state.");
} else
lease_timedout(cs);
}
// Triggered when a DHCP rebind request has been sent and no reply has been
// received within the response wait time. Check to see if the lease is still
// valid, and if it is, send a broadcast DHCP renew packet. If it is not, then
// change to the SELECTING state to get a new lease.
static void rebinding_timeout(struct client_state_t *cs)
{
/* Either set a new rebindTime, or enter INIT state */
if ((cs->lease - cs->rebindTime) <= (cs->lease / 14400 + 1)) {
/* timed out, enter init state */
cs->dhcpState = DS_SELECTING;
log_line("Lease lost, entering init state.");
ifchange(NULL, IFCHANGE_DECONFIG);
cs->timeout = 0;
cs->packetNum = 0;
change_listen_mode(cs, LM_RAW);
} else {
/* send a request packet */
send_renew(cs->xid, 0, cs->requestedIP); /* broadcast */
cs->rebindTime = ((cs->lease - cs->rebindTime) >> 1) + cs->rebindTime;
cs->timeout = (cs->rebindTime * 1000) - (curms() - cs->leaseStartTime);
}
long long ct = curms();
long long elt = cs->leaseStartTime + cs->lease * 1000;
if (ct < elt) {
long long wt = (elt - ct) / 2;
if (wt >= 30000)
send_renew(cs->xid, 0, cs->requestedIP);
else
wt = elt - ct;
cs->timeout = wt;
} else
lease_timedout(cs);
}
static void released_timeout(struct client_state_t *cs)