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#include <u.h>
#include <libc.h>
#include <ip.h>
#include <thread.h>
#include "netbios.h"
void
nbnsmessagequestionfree(NbnsMessageQuestion **qp)
{
NbnsMessageQuestion *q = *qp;
if (q) {
free(q);
*qp = nil;
}
}
void
nbnsmessageresourcefree(NbnsMessageResource **rp)
{
NbnsMessageResource *r = *rp;
if (r) {
free(r->rdata);
free(r);
*rp = nil;
}
}
static void
questionfree(NbnsMessageQuestion **qp)
{
while (*qp) {
NbnsMessageQuestion *next = (*qp)->next;
nbnsmessagequestionfree(qp);
*qp = next;
}
}
static void
resourcefree(NbnsMessageResource **rp)
{
while (*rp) {
NbnsMessageResource *next = (*rp)->next;
nbnsmessageresourcefree(rp);
*rp = next;
}
}
void
nbnsmessagefree(NbnsMessage **sp)
{
NbnsMessage *s = *sp;
if (s) {
questionfree(&s->q);
resourcefree(&s->an);
resourcefree(&s->ns);
resourcefree(&s->ar);
free(s);
*sp = nil;
}
}
void
nbnsmessageaddquestion(NbnsMessage *s, NbnsMessageQuestion *q)
{
NbnsMessageQuestion **qp;
for (qp = &s->q; *qp; qp = &(*qp)->next)
;
*qp = q;
}
NbnsMessageQuestion *
nbnsmessagequestionnew(NbName name, ushort type, ushort class)
{
NbnsMessageQuestion *q;
q = mallocz(sizeof(*q), 1);
if (q == nil)
return nil;
nbnamecpy(q->name, name);
q->type = type;
q->class = class;
return q;
}
NbnsMessageResource *
nbnsmessageresourcenew(NbName name, ushort type, ushort class, ulong ttl, int rdlength, uchar *rdata)
{
NbnsMessageResource *r;
r= mallocz(sizeof(*r), 1);
if (r == nil)
return nil;
nbnamecpy(r->name, name);
r->type = type;
r->class = class;
r->ttl = ttl;
r->rdlength = rdlength;
if (rdlength) {
r->rdata = malloc(rdlength);
if (r->rdata == nil) {
free(r);
return nil;
}
memcpy(r->rdata, rdata, rdlength);
}
return r;
}
void
nbnsmessageaddresource(NbnsMessageResource **rp, NbnsMessageResource *r)
{
for (; *rp; rp = &(*rp)->next)
;
*rp = r;
}
NbnsMessage *
nbnsmessagenew(void)
{
return mallocz(sizeof(NbnsMessage), 1);
}
static int
resourcedecode(NbnsMessageResource **headp, int count, uchar *ap, uchar *pp, uchar *ep)
{
uchar *p = pp;
int i;
for (i = 0; i < count; i++) {
int n;
NbnsMessageResource *r, **rp;
r = mallocz(sizeof(NbnsMessageResource), 1);
if (r == nil)
return -1;
for (rp = headp; *rp; rp = &(*rp)->next)
;
*rp = r;
n = nbnamedecode(ap, p, ep, r->name);
if (n == 0)
return -1;
p += n;
if (p + 10 > ep)
return -1;
r->type = nhgets(p); p += 2;
r->class = nhgets(p); p += 2;
r->ttl = nhgetl(p); p += 4;
r->rdlength = nhgets(p); p += 2;
//print("rdlength %d\n", r->rdlength);
if (r->rdlength) {
if (p + r->rdlength > ep)
return -1;
r->rdata = malloc(r->rdlength);
if (r == nil)
return -1;
memcpy(r->rdata, p, r->rdlength);
p += r->rdlength;
}
}
return p - pp;
}
NbnsMessage *
nbnsconvM2S(uchar *ap, int nap)
{
uchar *p, *ep;
ushort qdcount, ancount, nscount, arcount, ctrl;
int i;
NbnsMessage *s;
int n;
if (nap < 12)
return nil;
p = ap;
ep = ap + nap;
s = nbnsmessagenew();
if (s == nil)
return nil;
s->id = nhgets(p); p+= 2;
ctrl = nhgets(p); p += 2;
qdcount = nhgets(p); p += 2;
ancount = nhgets(p); p += 2;
nscount = nhgets(p); p += 2;
arcount = nhgets(p); p += 2;
s->response = (ctrl & NbnsResponse) != 0;
s->opcode = (ctrl >> NbnsOpShift) & NbnsOpMask;
s->broadcast = (ctrl & NbnsFlagBroadcast) != 0;
s->recursionavailable = (ctrl & NbnsFlagRecursionAvailable) != 0;
s->recursiondesired = (ctrl & NbnsFlagRecursionDesired) != 0;
s->truncation = (ctrl & NbnsFlagTruncation) != 0;
s->authoritativeanswer = (ctrl & NbnsFlagAuthoritativeAnswer) != 0;
s->rcode = s->response ? (ctrl & NbnsRcodeMask) : 0;
for (i = 0; i < qdcount; i++) {
int n;
NbName nbname;
NbnsMessageQuestion *q;
ushort type, class;
n = nbnamedecode(ap, p, ep, nbname);
if (n == 0)
goto fail;
p += n;
if (p + 4 > ep)
goto fail;
type = nhgets(p); p += 2;
class = nhgets(p); p += 2;
q = nbnsmessagequestionnew(nbname, type, class);
if (q == nil)
goto fail;
nbnsmessageaddquestion(s, q);
}
n = resourcedecode(&s->an, ancount, ap, p, ep);
if (n < 0)
goto fail;
p += n;
n = resourcedecode(&s->ns, nscount, ap, p, ep);
if (n < 0)
goto fail;
p += n;
n = resourcedecode(&s->ar, arcount, ap, p, ep);
if (n < 0)
goto fail;
//print("arcount %d\n", arcount);
return s;
fail:
nbnsmessagefree(&s);
return nil;
}
static int
resourceencode(NbnsMessageResource *r, uchar *ap, uchar *ep)
{
uchar *p = ap;
for (; r; r = r->next) {
int n = nbnameencode(p, ep, r->name);
if (n == 0)
return -1;
p += n;
if (p + 10 > ep)
return -1;
hnputs(p, r->type); p += 2;
hnputs(p, r->class); p += 2;
hnputl(p, r->ttl); p += 4;
hnputs(p, r->rdlength); p += 2;
if (p + r->rdlength > ep)
return -1;
memcpy(p, r->rdata, r->rdlength);
p += r->rdlength;
}
return p - ap;
}
int
nbnsconvS2M(NbnsMessage *s, uchar *ap, int nap)
{
uchar *p = ap;
uchar *ep = ap + nap;
ushort ctrl;
NbnsMessageQuestion *q;
NbnsMessageResource *r;
int k;
int n;
if (p + 12 > ep)
return 0;
hnputs(p, s->id); p+= 2;
ctrl = (s->opcode & NbnsOpMask) << NbnsOpShift;
if (s->response) {
ctrl |= s->rcode & NbnsRcodeMask;
ctrl |= NbnsResponse;
}
if (s->broadcast)
ctrl |= NbnsFlagBroadcast;
if (s->recursionavailable)
ctrl |= NbnsFlagRecursionAvailable;
if (s->recursiondesired)
ctrl |= NbnsFlagRecursionDesired;
if (s->truncation)
ctrl |= NbnsFlagTruncation;
if (s->authoritativeanswer)
ctrl |= NbnsFlagAuthoritativeAnswer;
hnputs(p, ctrl); p += 2;
for (q = s->q, k = 0; q; k++, q = q->next)
;
hnputs(p, k); p += 2;
for (r = s->an, k = 0; r; k++, r = r->next)
;
hnputs(p, k); p += 2;
for (r = s->ns, k = 0; r; k++, r = r->next)
;
hnputs(p, k); p += 2;
for (r = s->ar, k = 0; r; k++, r = r->next)
;
hnputs(p, k); p += 2;
for (q = s->q; q; q = q->next) {
int n = nbnameencode(p, ep, q->name);
if (n == 0)
return 0;
p += n;
if (p + 4 > ep)
return 0;
hnputs(p, q->type); p += 2;
hnputs(p, q->class); p += 2;
}
n = resourceencode(s->an, p, ep);
if (n < 0)
return 0;
p += n;
n = resourceencode(s->ns, p, ep);
if (n < 0)
return 0;
p += n;
n = resourceencode(s->ar, p, ep);
if (n < 0)
return 0;
p += n;
return p - ap;
}