int
openlisten(char *net)
{
int n, fd, cfd;
char data[128], devdir[40];
// sprint(data, "%s/udp!*!bootpc", net);
sprint(data, "%s/udp!*!68", net);
for(n = 0; ; n++) {
cfd = announce(data, devdir);
if(cfd >= 0)
break;
/* might be another client - wait and try again */
fprint(2, "dhcpclient: can't announce %s: %r", data);
sleep(1000);
if(n > 10)
myfatal("can't announce: giving up: %r");
}
if(fprint(cfd, "headers") < 0)
myfatal("can't set header mode: %r");
sprint(data, "%s/data", devdir);
fd = open(data, ORDWR);
if(fd < 0)
myfatal("open %s: %r", data);
close(cfd);
return fd;
}
void
dhcpsend(int type)
{
int n;
uint8_t *p;
Bootp bp;
Udphdr *up;
memset(&bp, 0, sizeof bp);
up = (Udphdr*)bp.udphdr;
hnputs(up->rport, 67);
bp.op = Bootrequest;
hnputl(bp.xid, dhcp.xid);
hnputs(bp.secs, time(0) - dhcp.starttime);
hnputs(bp.flags, Fbroadcast); /* reply must be broadcast */
memmove(bp.optmagic, optmagic, 4);
p = bp.optdata;
p = optaddbyte(p, ODtype, type);
p = optadd(p, ODclientid, dhcp.cid, strlen(dhcp.cid));
switch(type) {
default:
myfatal("dhcpsend: unknown message type: %d", type);
case Discover:
ipmove(up->raddr, IPv4bcast); /* broadcast */
break;
case Request:
if(dhcp.state == Sbound || dhcp.state == Srenewing)
ipmove(up->raddr, dhcp.server);
else
ipmove(up->raddr, IPv4bcast); /* broadcast */
p = optaddulong(p, ODlease, dhcp.lease);
if(dhcp.state == Sselecting || dhcp.state == Srequesting) {
p = optaddaddr(p, ODipaddr, dhcp.client); /* mistake?? */
p = optaddaddr(p, ODserverid, dhcp.server);
} else
v6tov4(bp.ciaddr, dhcp.client);
break;
case Release:
ipmove(up->raddr, dhcp.server);
v6tov4(bp.ciaddr, dhcp.client);
p = optaddaddr(p, ODipaddr, dhcp.client);
p = optaddaddr(p, ODserverid, dhcp.server);
break;
}
*p++ = OBend;
n = p - (uint8_t*)&bp;
if(write(dhcp.fd, &bp, n) != n)
myfatal("dhcpsend: write failed: %r");
}
void
timerthread(void* v)
{
for(;;) {
sleep(1000);
qlock(&dhcp.lk);
if(--dhcp.timeout > 0) {
qunlock(&dhcp.lk);
continue;
}
switch(dhcp.state) {
default:
myfatal("timerthread: unknown state %d", dhcp.state);
case Sinit:
break;
case Sselecting:
dhcpsend(Discover);
dhcp.timeout = 4;
dhcp.resend++;
if(dhcp.resend>5)
myfatal("dhcp: giving up: selecting");
break;
case Srequesting:
dhcpsend(Request);
dhcp.timeout = 4;
dhcp.resend++;
if(dhcp.resend>5)
myfatal("dhcp: giving up: requesting");
break;
case Srenewing:
dhcpsend(Request);
dhcp.timeout = 1;
dhcp.resend++;
if(dhcp.resend>3) {
dhcp.state = Srebinding;
dhcp.resend = 0;
}
break;
case Srebinding:
dhcpsend(Request);
dhcp.timeout = 4;
dhcp.resend++;
if(dhcp.resend>5)
myfatal("dhcp: giving up: rebinding");
break;
case Sbound:
break;
}
qunlock(&dhcp.lk);
}
}
void *myrealloc(void *ptr, int size)
{
assert(size >= 0 && ptr);
void *p = realloc(ptr, size);
if(!p) {
myfatal("out of memory");
}
return p;
}
void *mymalloc(int size)
{
assert(size >= 0);
void *p = malloc(size);
if(!p) {
myfatal("out of memory");
}
return p;
}
uint32_t
thread(void(*f)(void*), void *a)
{
int pid;
pid = rfork(RFNOWAIT|RFMEM|RFPROC);
if(pid < 0)
myfatal("rfork failed: %r");
if(pid != 0)
return pid;
(*f)(a);
return 0; /* never reaches here */
}
void
dhcprecv(void)
{
uint8_t buf[2000];
Bootp *bp;
int n, type;
uint32_t lease;
uint8_t mask[IPaddrlen];
qunlock(&dhcp.lk);
n = read(dhcp.fd, buf, sizeof(buf));
qlock(&dhcp.lk);
if(n <= 0)
myfatal("dhcprecv: bad read: %r");
bp = parse(buf, n);
if(bp == 0)
return;
if(1) {
fprint(2, "recved\n");
bootpdump(buf, n);
}
type = optgetbyte(bp, ODtype);
switch(type) {
default:
fprint(2, "dhcprecv: unknown type: %d\n", type);
break;
case Offer:
if(dhcp.state != Sselecting)
break;
lease = optgetulong(bp, ODlease);
if(lease == 0)
myfatal("bad lease");
if(!optgetaddr(bp, OBmask, mask))
memset(mask, 0xff, sizeof(mask));
v4tov6(dhcp.client, bp->yiaddr);
if(!optgetaddr(bp, ODserverid, dhcp.server)) {
fprint(2, "dhcprecv: Offer from server with invalid serverid\n");
break;
}
dhcp.lease = lease;
ipmove(dhcp.mask, mask);
memmove(dhcp.sname, bp->sname, sizeof(dhcp.sname));
dhcp.sname[sizeof(dhcp.sname)-1] = 0;
dhcpsend(Request);
dhcp.state = Srequesting;
dhcp.resend = 0;
dhcp.timeout = 4;
break;
case Ack:
if(dhcp.state != Srequesting)
if(dhcp.state != Srenewing)
if(dhcp.state != Srebinding)
break;
lease = optgetulong(bp, ODlease);
if(lease == 0)
myfatal("bad lease");
if(!optgetaddr(bp, OBmask, mask))
memset(mask, 0xff, sizeof(mask));
v4tov6(dhcp.client, bp->yiaddr);
dhcp.lease = lease;
ipmove(dhcp.mask, mask);
dhcp.state = Sbound;
break;
case Nak:
myfatal("recved nak");
break;
}
}
