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#include <u.h>
#include <libc.h>
#include <ip.h>
#include <thread.h>
#include "netbios.h"
int
nbdgramconvM2S(NbDgram *s, uchar *ap, uchar *ep)
{
uchar *p = ap;
int n;
ushort length;
if (ap + 6 + IPv4addrlen > ep)
return 0;
s->type = *p++;
s->flags = *p++;
s->id = nhgets(p); p+= 2;
v4tov6(s->srcip, p); p+= IPv4addrlen;
s->srcport = nhgets(p); p += 2;
switch (s->type) {
case NbDgramDirectUnique:
case NbDgramDirectGroup:
case NbDgramBroadcast:
if (p + 4 > ep)
return 0;
length = nhgets(p); p += 2;
s->datagram.offset = nhgets(p); p += 2;
if (p + length > ep)
return 0;
ep = p + length;
n = nbnamedecode(p, p, ep, s->datagram.srcname);
if (n == 0)
return 0;
p += n;
n = nbnamedecode(p, p, ep, s->datagram.dstname);
if (n == 0)
return 0;
p += n;
s->datagram.data = p;
s->datagram.length = ep - p;
p = ep;
break;
case NbDgramError:
if (p + 1 > ep)
return 0;
s->error.code = *p++;
break;
case NbDgramQueryRequest:
case NbDgramPositiveQueryResponse:
case NbDgramNegativeQueryResponse:
n = nbnamedecode(p, p, ep, s->query.dstname);
if (n == 0)
return 0;
p += n;
break;
default:
return 0;
}
return p - ap;
}
int
nbdgramconvS2M(uchar *ap, uchar *ep, NbDgram *s)
{
uchar *p = ap;
uchar *fixup;
int n;
if (p + 6 + IPv4addrlen > ep)
return 0;
*p++ = s->type;
*p++ = s->flags;
hnputs(p, s->id); p+= 2;
v6tov4(p, s->srcip); p += IPv4addrlen;
hnputs(p, s->srcport); p+= 2;
switch (s->type) {
case NbDgramDirectUnique:
case NbDgramDirectGroup:
case NbDgramBroadcast:
if (p + 4 > ep)
return 0;
fixup = p;
hnputs(p, s->datagram.length); p += 2;
hnputs(p, s->datagram.offset); p += 2;
n = nbnameencode(p, ep, s->datagram.srcname);
if (n == 0)
return 0;
p += n;
n = nbnameencode(p, ep, s->datagram.dstname);
if (n == 0)
return 0;
p += n;
if (p + s->datagram.length > ep)
return 0;
memcpy(p, s->datagram.data, s->datagram.length); p += s->datagram.length;
hnputs(fixup, p - fixup - 4);
break;
case NbDgramError:
if (p + 1 > ep)
return 0;
*p++ = s->error.code;
break;
case NbDgramQueryRequest:
case NbDgramPositiveQueryResponse:
case NbDgramNegativeQueryResponse:
n = nbnameencode(p, ep, s->datagram.dstname);
if (n == 0)
return 0;
p += n;
break;
default:
return 0;
}
return p - ap;
}
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