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ipconfig: fix dhcp watch

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in dhcpwatch, the sleep time "secs" could become
zero potentially freezing the lease time.

give up when in Sinit state in dhcpquery() as this
is a terminal state.
This commit is contained in:
cinap_lenrek 2014-05-18 19:20:31 +02:00
parent 48a644aa31
commit c994152a90
2 changed files with 10 additions and 16 deletions
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2
sys/src/cmd/ip/ipconfig/ipconfig.h
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@ -103,7 +103,7 @@ void controldevice(void);
void dhcpquery(int, int); void dhcpquery(int, int);
void dhcprecv(void); void dhcprecv(void);
void dhcpsend(int); void dhcpsend(int);
int dhcptimer(void); void dhcptimer(void);
void dhcpwatch(int); void dhcpwatch(int);
void doadd(int); void doadd(int);
void doremove(void); void doremove(void);

24
sys/src/cmd/ip/ipconfig/main.c
View file

@ -182,7 +182,7 @@ void controldevice(void);
void dhcpquery(int, int); void dhcpquery(int, int);
void dhcprecv(void); void dhcprecv(void);
void dhcpsend(int); void dhcpsend(int);
int dhcptimer(void); void dhcptimer(void);
void dhcpwatch(int); void dhcpwatch(int);
void doadd(int); void doadd(int);
void doremove(void); void doremove(void);
@ -933,10 +933,9 @@ dhcpquery(int needconfig, int startstate)
conf.resend = 0; conf.resend = 0;
conf.timeout = time(0) + 4; conf.timeout = time(0) + 4;
while(conf.state != Sbound){ while(conf.state != Sbound && conf.state != Sinit){
dhcprecv(); dhcprecv();
if(dhcptimer() < 0) dhcptimer();
break;
} }
close(conf.fd); close(conf.fd);
@ -956,8 +955,7 @@ enum {
void void
dhcpwatch(int needconfig) dhcpwatch(int needconfig)
{ {
int secs, s; ulong secs, s, t;
ulong t;
if(nodhcpwatch) if(nodhcpwatch)
return; return;
@ -973,10 +971,9 @@ dhcpwatch(int needconfig)
procsetname("dhcpwatch"); procsetname("dhcpwatch");
/* keep trying to renew the lease */ /* keep trying to renew the lease */
for(;;){ for(;;){
if(conf.lease == 0) secs = conf.lease/2;
if(secs < 5)
secs = 5; secs = 5;
else
secs = conf.lease >> 1;
/* avoid overflows */ /* avoid overflows */
for(s = secs; s > 0; s -= t){ for(s = secs; s > 0; s -= t){
@ -1022,14 +1019,14 @@ dhcpwatch(int needconfig)
} }
} }
int void
dhcptimer(void) dhcptimer(void)
{ {
ulong now; ulong now;
now = time(0); now = time(0);
if(now < conf.timeout) if(now < conf.timeout)
return 0; return;
switch(conf.state) { switch(conf.state) {
default: default:
@ -1042,10 +1039,8 @@ dhcptimer(void)
case Srebinding: case Srebinding:
dhcpsend(conf.state == Sselecting? Discover: Request); dhcpsend(conf.state == Sselecting? Discover: Request);
conf.timeout = now + 4; conf.timeout = now + 4;
if(++conf.resend > 5) { if(++conf.resend > 5)
conf.state = Sinit; conf.state = Sinit;
return -1;
}
break; break;
case Srenewing: case Srenewing:
dhcpsend(Request); dhcpsend(Request);
@ -1056,7 +1051,6 @@ dhcptimer(void)
} }
break; break;
} }
return 0;
} }
void void