static void
tcpreader(void *a)
{
Session *s = a;
uchar *buf;
int buflen = 0x1ffff + 4;
buf = nbemalloc(buflen);
for (;;) {
int n;
uchar flags;
ushort length;
n = readn(s->fd, buf, 4);
if (n != 4) {
die:
free(buf);
if (s->state == Connected)
(*s->write)(s, nil, -1);
deletesession(s);
return;
}
flags = buf[1];
length = nhgets(buf + 2) | ((flags & 1) << 16);
n = readn(s->fd, buf + 4, length);
if (n != length)
goto die;
if (flags & 0xfe) {
print("nbss: invalid flags field 0x%.2ux\n", flags);
goto die;
}
switch (buf[0]) {
case 0: /* session message */
if (s->state != Connected && s->state != Dead) {
print("nbss: unexpected session message\n");
goto die;
}
if (s->state == Connected) {
if ((*s->write)(s, buf + 4, length) != 0) {
s->state = Dead;
goto die;
}
}
break;
case 0x81: /* session request */ {
uchar *p, *ep;
Listen *l;
int k;
int called_found;
uchar error_code;
if (s->state == Connected) {
print("nbss: unexpected session request\n");
goto die;
}
p = buf + 4;
ep = p + length;
k = nbnamedecode(p, p, ep, s->to);
if (k == 0) {
print("nbss: malformed called name in session request\n");
goto die;
}
p += k;
k = nbnamedecode(p, p, ep, s->from);
if (k == 0) {
print("nbss: malformed calling name in session request\n");
goto die;
}
/*
p += k;
if (p != ep) {
print("nbss: extra data at end of session request\n");
goto die;
}
*/
called_found = 0;
//print("nbss: called %B calling %B\n", s->to, s->from);
qlock(&listens);
for (l = listens.head; l; l = l->next)
if (nbnameequal(l->to, s->to)) {
called_found = 1;
if (nbnameequal(l->from, s->from))
break;
}
if (l == nil) {
qunlock(&listens);
error_code = called_found ? 0x81 : 0x80;
replydie:
buf[0] = 0x83;
buf[1] = 0;
hnputs(buf + 2, 1);
buf[4] = error_code;
write(s->fd, buf, 5);
goto die;
}
if (!(*l->accept)(l->magic, s, &s->write)) {
qunlock(&listens);
error_code = 0x83;
goto replydie;
}
buf[0] = 0x82;
buf[1] = 0;
hnputs(buf + 2, 0);
if (write(s->fd, buf, 4) != 4) {
qunlock(&listens);
goto die;
}
s->state = Connected;
qunlock(&listens);
break;
}
case 0x85: /* keep awake */
break;
default:
print("nbss: opcode 0x%.2ux unexpected\n", buf[0]);
goto die;
}
}
}
static void
udplistener(void *)
{
//print("udplistener - starting\n");
for (;;) {
uint8_t msg[Udphdrsize + 576];
int len = read(udp.fd, msg, sizeof(msg));
if (len < 0)
break;
if (len >= nbudphdrsize) {
NbDgram s;
// Udphdr *uh;
uint8_t *p;
int n;
// uh = (Udphdr*)msg;
p = msg + nbudphdrsize;
len -= nbudphdrsize;
n = nbdgramconvM2S(&s, p, p + len);
if (n) {
switch (s.type) {
case NbDgramError:
print("nbdgramlisten: error: ip %I port %d code 0x%.2x\n", s.srcip, s.srcport, s.error.code);
break;
case NbDgramDirectUnique:
case NbDgramDirectGroup:
case NbDgramBroadcast: {
int delivered = 0;
Listen **lp, *l;
if ((s.flags & NbDgramMore) || s.datagram.offset != 0)
break;
if (!nbnameisany(s.datagram.dstname)
&& !nbnametablefind(s.datagram.dstname, 0)) {
/* - only do this if a broadcast node, and can tell when packets are broadcast...
s.flags &= 3;
ipmove(s.srcip, nbglobals.myipaddr);
s.srcport = NbDgramPort;
s.type = NbDgramError;
s.error.code = NbDgramErrorDestinationNameNotPresent;
nbdgramsendto(uh->raddr, nhgets(uh->rport), &s);
*/
break;
}
qlock(&listens);
for (lp = &listens.head; (l = *lp) != nil;) {
if (nbnameisany(l->to) || nbnameequal(l->to, s.datagram.dstname)) {
switch ((*l->deliver)(l->magic, &s)) {
case 0:
delivered = 1;
/* fall through */
case -1:
*lp = l->next;
free(l);
continue;
default:
delivered = 1;
break;
}
}
lp = &l->next;
}
qunlock(&listens);
USED(delivered);
}
default:
;
}
}
}
}
print("udplistener - exiting\n");
qlock(&udp);
udp.thread = -1;
qunlock(&udp);
}
