jdns_packet_t *jdns_packet_copy(const jdns_packet_t *a)
{
jdns_packet_t *c = jdns_packet_new();
c->id = a->id;
c->opts.qr = a->opts.qr;
c->opts.opcode = a->opts.opcode;
c->opts.aa = a->opts.aa;
c->opts.tc = a->opts.tc;
c->opts.rd = a->opts.rd;
c->opts.ra = a->opts.ra;
c->opts.z = a->opts.z;
c->opts.rcode = a->opts.rcode;
jdns_list_delete(c->questions);
jdns_list_delete(c->answerRecords);
jdns_list_delete(c->authorityRecords);
jdns_list_delete(c->additionalRecords);
c->questions = jdns_list_copy(a->questions);
c->answerRecords = jdns_list_copy(a->answerRecords);
c->authorityRecords = jdns_list_copy(a->authorityRecords);
c->additionalRecords = jdns_list_copy(a->additionalRecords);
c->fully_parsed = a->fully_parsed;
c->raw_size = a->raw_size;
c->raw_data = jdns_copy_array(a->raw_data, a->raw_size);
return c;
}
static int process_rrsection(jdns_list_t *dest, int count, const unsigned char *data, int size, const unsigned char **bufp)
{
int n;
int offset, at;
jdns_string_t *name = 0;
const unsigned char *buf;
buf = *bufp;
for(n = 0; n < count; ++n)
{
jdns_packet_resource_t *r;
offset = buf - data;
at = 0;
if(!readlabel(data + offset, size - offset, data, size, &at, &name))
goto error;
offset += at;
// need 10 more bytes
if(offset + 10 > size)
goto error;
buf = data + offset;
r = jdns_packet_resource_new();
r->qname = name;
name = 0;
r->qtype = net2short(&buf);
r->qclass = net2short(&buf);
r->ttl = net2long(&buf);
r->rdlength = net2short(&buf);
offset = buf - data;
// make sure we have enough for the rdata
if(size - offset < r->rdlength)
{
jdns_packet_resource_delete(r);
goto error;
}
r->rdata = jdns_copy_array(buf, r->rdlength);
buf += r->rdlength;
jdns_list_insert_value(dest, r, -1);
jdns_packet_resource_delete(r);
}
*bufp = buf;
return 1;
error:
jdns_string_delete(name);
return 0;
}
jdns_packet_resource_t *jdns_packet_resource_copy(const jdns_packet_resource_t *a)
{
jdns_packet_resource_t *c = jdns_packet_resource_new();
if(a->qname)
c->qname = jdns_string_copy(a->qname);
c->qtype = a->qtype;
c->qclass = a->qclass;
c->ttl = a->ttl;
c->rdlength = a->rdlength;
c->rdata = jdns_copy_array(a->rdata, a->rdlength);
jdns_list_delete(c->writelog);
c->writelog = jdns_list_copy(a->writelog);
return c;
}
int jdns_packet_import(jdns_packet_t **a, const unsigned char *data, int size)
{
jdns_packet_t *tmp = 0;
const unsigned char *buf;
// need at least some data
if(!data || size == 0)
return 0;
// header (id + options + item counts) is 12 bytes
if(size < 12)
goto error;
tmp = jdns_packet_new();
buf = data;
// id
tmp->id = net2short(&buf);
// options
if(buf[0] & 0x80) // qr is bit 7
tmp->opts.qr = 1;
tmp->opts.opcode = (buf[0] & 0x78) >> 3; // opcode is bits 6,5,4,3
if(buf[0] & 0x04) // aa is bit 2
tmp->opts.aa = 1;
if(buf[0] & 0x02) // tc is bit 1
tmp->opts.tc = 1;
if(buf[0] & 0x01) // rd is bit 0
tmp->opts.rd = 1;
if(buf[1] & 0x80) // ra is bit 7 (second byte)
tmp->opts.ra = 1;
tmp->opts.z = (buf[1] & 0x70) >> 4; // z is bits 6,5,4
tmp->opts.rcode = buf[1] & 0x0f; // rcode is bits 3,2,1,0
buf += 2;
// item counts
tmp->qdcount = net2short(&buf);
tmp->ancount = net2short(&buf);
tmp->nscount = net2short(&buf);
tmp->arcount = net2short(&buf);
// if these fail, we don't count them as errors, since the packet
// might have been truncated
if(!process_qsection(tmp->questions, tmp->qdcount, data, size, &buf))
goto skip;
if(!process_rrsection(tmp->answerRecords, tmp->ancount, data, size, &buf))
goto skip;
if(!process_rrsection(tmp->authorityRecords, tmp->nscount, data, size, &buf))
goto skip;
if(!process_rrsection(tmp->additionalRecords, tmp->arcount, data, size, &buf))
goto skip;
tmp->fully_parsed = 1;
skip:
// keep the raw data for reference during rdata parsing
tmp->raw_size = size;
tmp->raw_data = jdns_copy_array(data, size);
*a = tmp;
return 1;
error:
jdns_packet_delete(tmp);
return 0;
}
