/** check if DNAME applies to a name */
static int
pkt_strict_sub(ldns_buffer* pkt, uint8_t* sname, uint8_t* dr)
{
uint8_t buf1[LDNS_MAX_DOMAINLEN+1];
uint8_t buf2[LDNS_MAX_DOMAINLEN+1];
/* decompress names */
dname_pkt_copy(pkt, buf1, sname);
dname_pkt_copy(pkt, buf2, dr);
return dname_strict_subdomain_c(buf1, buf2);
}
/** remove rrset, update loop variables */
static void
remove_rrset(const char* str, ldns_buffer* pkt, struct msg_parse* msg,
struct rrset_parse* prev, struct rrset_parse** rrset)
{
if(verbosity >= VERB_QUERY
&& (*rrset)->dname_len <= LDNS_MAX_DOMAINLEN) {
uint8_t buf[LDNS_MAX_DOMAINLEN+1];
dname_pkt_copy(pkt, buf, (*rrset)->dname);
log_nametypeclass(VERB_QUERY, str, buf,
(*rrset)->type, ntohs((*rrset)->rrset_class));
}
if(prev)
prev->rrset_all_next = (*rrset)->rrset_all_next;
else msg->rrset_first = (*rrset)->rrset_all_next;
if(msg->rrset_last == *rrset)
msg->rrset_last = prev;
msg->rrset_count --;
switch((*rrset)->section) {
case LDNS_SECTION_ANSWER:
msg->an_rrsets--;
break;
case LDNS_SECTION_AUTHORITY:
msg->ns_rrsets--;
break;
case LDNS_SECTION_ADDITIONAL:
msg->ar_rrsets--;
break;
default:
log_assert(0);
}
msgparse_bucket_remove(msg, *rrset);
*rrset = (*rrset)->rrset_all_next;
}
/** check subdomain with decompression, compressed is parent */
static int
sub_of_pkt(ldns_buffer* pkt, uint8_t* zone, uint8_t* comprname)
{
uint8_t buf[LDNS_MAX_DOMAINLEN+1];
dname_pkt_copy(pkt, buf, comprname);
return dname_subdomain_c(zone, buf);
}
int
parse_copy_decompress_rrset(sldns_buffer* pkt, struct msg_parse* msg,
struct rrset_parse *pset, struct regional* region,
struct ub_packed_rrset_key* pk)
{
struct packed_rrset_data* data;
pk->rk.flags = pset->flags;
pk->rk.dname_len = pset->dname_len;
if(region)
pk->rk.dname = (uint8_t*)regional_alloc(
region, pset->dname_len);
else pk->rk.dname =
(uint8_t*)malloc(pset->dname_len);
if(!pk->rk.dname)
return 0;
/** copy & decompress dname */
dname_pkt_copy(pkt, pk->rk.dname, pset->dname);
/** copy over type and class */
pk->rk.type = htons(pset->type);
pk->rk.rrset_class = pset->rrset_class;
/** read data part. */
if(!parse_create_rrset(pkt, pset, &data, region))
return 0;
pk->entry.data = (void*)data;
pk->entry.key = (void*)pk;
pk->entry.hash = pset->hash;
data->trust = get_rrset_trust(msg, pset);
return 1;
}
/** check subdomain with decompression */
static int
pkt_sub(sldns_buffer* pkt, uint8_t* comprname, uint8_t* zone)
{
uint8_t buf[LDNS_MAX_DOMAINLEN+1];
dname_pkt_copy(pkt, buf, comprname);
return dname_subdomain_c(buf, zone);
}
/** synthesize a CNAME rrset */
static struct rrset_parse*
synth_cname_rrset(uint8_t** sname, size_t* snamelen, uint8_t* alias,
size_t aliaslen, struct regional* region, struct msg_parse* msg,
struct rrset_parse* rrset, struct rrset_parse* prev,
struct rrset_parse* nx, ldns_buffer* pkt)
{
struct rrset_parse* cn = (struct rrset_parse*)regional_alloc(region,
sizeof(struct rrset_parse));
if(!cn)
return NULL;
memset(cn, 0, sizeof(*cn));
cn->rr_first = (struct rr_parse*)regional_alloc(region,
sizeof(struct rr_parse));
if(!cn->rr_first)
return NULL;
cn->rr_last = cn->rr_first;
/* CNAME from sname to alias */
cn->dname = (uint8_t*)regional_alloc(region, *snamelen);
if(!cn->dname)
return NULL;
dname_pkt_copy(pkt, cn->dname, *sname);
cn->dname_len = *snamelen;
cn->type = LDNS_RR_TYPE_CNAME;
cn->section = rrset->section;
cn->rrset_class = rrset->rrset_class;
cn->rr_count = 1;
cn->size = sizeof(uint16_t) + aliaslen;
cn->hash=pkt_hash_rrset(pkt, cn->dname, cn->type, cn->rrset_class, 0);
/* allocate TTL + rdatalen + uncompressed dname */
memset(cn->rr_first, 0, sizeof(struct rr_parse));
cn->rr_first->outside_packet = 1;
cn->rr_first->ttl_data = (uint8_t*)regional_alloc(region,
sizeof(uint32_t)+sizeof(uint16_t)+aliaslen);
if(!cn->rr_first->ttl_data)
return NULL;
ldns_write_uint32(cn->rr_first->ttl_data, 0); /* TTL = 0 */
ldns_write_uint16(cn->rr_first->ttl_data+4, aliaslen);
memmove(cn->rr_first->ttl_data+6, alias, aliaslen);
cn->rr_first->size = sizeof(uint16_t)+aliaslen;
/* link it in */
cn->rrset_all_next = nx;
if(prev)
prev->rrset_all_next = cn;
else msg->rrset_first = cn;
if(nx == NULL)
msg->rrset_last = cn;
msg->rrset_count ++;
msg->an_rrsets++;
/* it is not inserted in the msg hashtable. */
*sname = cn->rr_first->ttl_data + sizeof(uint32_t)+sizeof(uint16_t);
*snamelen = aliaslen;
return cn;
}
/** Synthesize CNAME from DNAME, false if too long */
static int
synth_cname(uint8_t* qname, size_t qnamelen, struct rrset_parse* dname_rrset,
uint8_t* alias, size_t* aliaslen, ldns_buffer* pkt)
{
/* we already know that sname is a strict subdomain of DNAME owner */
uint8_t* dtarg = NULL;
size_t dtarglen;
if(!parse_get_cname_target(dname_rrset, &dtarg, &dtarglen))
return 0;
log_assert(qnamelen > dname_rrset->dname_len);
/* DNAME from com. to net. with qname example.com. -> example.net. */
/* so: \3com\0 to \3net\0 and qname \7example\3com\0 */
*aliaslen = qnamelen + dtarglen - dname_rrset->dname_len;
if(*aliaslen > LDNS_MAX_DOMAINLEN)
return 0; /* should have been RCODE YXDOMAIN */
/* decompress dnames into buffer, we know it fits */
dname_pkt_copy(pkt, alias, qname);
dname_pkt_copy(pkt, alias+(qnamelen-dname_rrset->dname_len), dtarg);
return 1;
}
/** allocate qinfo, return 0 on error */
static int
parse_create_qinfo(sldns_buffer* pkt, struct msg_parse* msg,
struct query_info* qinf, struct regional* region)
{
if(msg->qname) {
if(region)
qinf->qname = (uint8_t*)regional_alloc(region,
msg->qname_len);
else qinf->qname = (uint8_t*)malloc(msg->qname_len);
if(!qinf->qname) return 0;
dname_pkt_copy(pkt, qinf->qname, msg->qname);
} else qinf->qname = 0;
qinf->qname_len = msg->qname_len;
qinf->qtype = msg->qtype;
qinf->qclass = msg->qclass;
return 1;
}
/** do the rdata copy */
static int
rdata_copy(sldns_buffer* pkt, struct packed_rrset_data* data, uint8_t* to,
struct rr_parse* rr, time_t* rr_ttl, uint16_t type,
sldns_pkt_section section)
{
uint16_t pkt_len;
const sldns_rr_descriptor* desc;
*rr_ttl = sldns_read_uint32(rr->ttl_data);
/* RFC 2181 Section 8. if msb of ttl is set treat as if zero. */
if(*rr_ttl & 0x80000000U)
*rr_ttl = 0;
if(type == LDNS_RR_TYPE_SOA && section == LDNS_SECTION_AUTHORITY) {
/* negative response. see if TTL of SOA record larger than the
* minimum-ttl in the rdata of the SOA record */
if(*rr_ttl > soa_find_minttl(rr))
*rr_ttl = soa_find_minttl(rr);
if(*rr_ttl > MAX_NEG_TTL)
*rr_ttl = MAX_NEG_TTL;
}
if(*rr_ttl < MIN_TTL)
*rr_ttl = MIN_TTL;
if(*rr_ttl < data->ttl)
data->ttl = *rr_ttl;
if(rr->outside_packet) {
/* uncompressed already, only needs copy */
memmove(to, rr->ttl_data+sizeof(uint32_t), rr->size);
return 1;
}
sldns_buffer_set_position(pkt, (size_t)
(rr->ttl_data - sldns_buffer_begin(pkt) + sizeof(uint32_t)));
/* insert decompressed size into rdata len stored in memory */
/* -2 because rdatalen bytes are not included. */
pkt_len = htons(rr->size - 2);
memmove(to, &pkt_len, sizeof(uint16_t));
to += 2;
/* read packet rdata len */
pkt_len = sldns_buffer_read_u16(pkt);
if(sldns_buffer_remaining(pkt) < pkt_len)
return 0;
desc = sldns_rr_descript(type);
if(pkt_len > 0 && desc && desc->_dname_count > 0) {
int count = (int)desc->_dname_count;
int rdf = 0;
size_t len;
size_t oldpos;
/* decompress dnames. */
while(pkt_len > 0 && count) {
switch(desc->_wireformat[rdf]) {
case LDNS_RDF_TYPE_DNAME:
oldpos = sldns_buffer_position(pkt);
dname_pkt_copy(pkt, to,
sldns_buffer_current(pkt));
to += pkt_dname_len(pkt);
pkt_len -= sldns_buffer_position(pkt)-oldpos;
count--;
len = 0;
break;
case LDNS_RDF_TYPE_STR:
len = sldns_buffer_current(pkt)[0] + 1;
break;
default:
len = get_rdf_size(desc->_wireformat[rdf]);
break;
}
if(len) {
memmove(to, sldns_buffer_current(pkt), len);
to += len;
sldns_buffer_skip(pkt, (ssize_t)len);
log_assert(len <= pkt_len);
pkt_len -= len;
}
rdf++;
}
}
/* copy remaining rdata */
if(pkt_len > 0)
memmove(to, sldns_buffer_current(pkt), pkt_len);
return 1;
}
