getdns/src/rr-iter.h

210 lines
6.9 KiB
C

/**
*
* /brief RR iterator over wireformat DNS packet
*/
/*
* Copyright (c) 2013, NLnet Labs, Verisign, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the names of the copyright holders nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL Verisign, Inc. BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef RR_ITER_H_
#define RR_ITER_H_
#include "rr-dict.h"
#include "gldns/pkthdr.h"
typedef enum _getdns_section {
SECTION_QUESTION = 1,
SECTION_ANSWER = 2,
SECTION_AUTHORITY = 4,
SECTION_ADDITIONAL = 8,
SECTION_ANY = 15,
SECTION_NO_QUESTION = 14,
SECTION_NO_ADDITIONAL = 6
} _getdns_section;
int _getdns_dname_equal(const uint8_t *s1, const uint8_t *s2);
typedef struct _getdns_rr_iter {
const uint8_t *pkt;
const uint8_t *pkt_end;
/* Which RR are we currently at */
size_t n;
/* pos points to start of the owner name the RR.
* Or is NULL when there are no RR's left.
*/
const uint8_t *pos;
/* rr_type will point to the rr_type right after the RR's owner name.
* rr_type is guaranteed to have a value when pos has a value
*/
const uint8_t *rr_type;
/* nxt point to the owner name of the next RR or to pkt_end */
const uint8_t *nxt;
} _getdns_rr_iter;
_getdns_rr_iter *_getdns_rr_iter_init(_getdns_rr_iter *i,
const uint8_t *pkt, const size_t pkt_len);
_getdns_rr_iter *_getdns_single_rr_iter_init(_getdns_rr_iter *i,
const uint8_t *wire, const size_t wire_len);
static inline _getdns_rr_iter *_getdns_rr_iter_rewind(_getdns_rr_iter *i)
{ return _getdns_rr_iter_init(i, i->pkt, i->pkt_end - i->pkt); }
_getdns_rr_iter *_getdns_rr_iter_next(_getdns_rr_iter *i);
const uint8_t *_getdns_owner_if_or_as_decompressed(
_getdns_rr_iter *i, uint8_t *ff_bytes, size_t *len);
static inline _getdns_section
_getdns_rr_iter_section(_getdns_rr_iter *i)
{
return !i->pkt ? (i->nxt - i->rr_type == 4 ? SECTION_QUESTION
: SECTION_ANSWER )
: i->n < (size_t)GLDNS_QDCOUNT(i->pkt) ? SECTION_QUESTION
: i->n < (size_t)GLDNS_QDCOUNT(i->pkt)
+ GLDNS_ANCOUNT(i->pkt) ? SECTION_ANSWER
: i->n < (size_t)GLDNS_QDCOUNT(i->pkt)
+ GLDNS_ANCOUNT(i->pkt)
+ GLDNS_NSCOUNT(i->pkt) ? SECTION_AUTHORITY
: i->n < (size_t)GLDNS_QDCOUNT(i->pkt)
+ GLDNS_ANCOUNT(i->pkt)
+ GLDNS_NSCOUNT(i->pkt)
+ GLDNS_ARCOUNT(i->pkt) ? SECTION_ADDITIONAL
: SECTION_ANY;
}
/* Utility functions to read rr_type and rr_class from a rr iterator */
static inline uint16_t rr_iter_type(_getdns_rr_iter *rr)
{ return rr->rr_type + 2 <= rr->nxt ? gldns_read_uint16(rr->rr_type) : 0; }
static inline uint16_t rr_iter_class(_getdns_rr_iter *rr)
{ return rr->rr_type + 4 <= rr->nxt ? gldns_read_uint16(rr->rr_type + 2) : 0; }
typedef struct _getdns_rrset {
const uint8_t *name;
uint16_t rr_class;
uint16_t rr_type;
const uint8_t *pkt;
size_t pkt_len;
_getdns_section sections;
} _getdns_rrset;
typedef struct _getdns_rrset_spc {
_getdns_rrset rrset;
uint8_t name_spc[256];
size_t name_len;
} _getdns_rrset_spc;
_getdns_rrset *_getdns_rrset_answer(
_getdns_rrset_spc *rrset2init, const uint8_t *pkt, size_t pkt_len);
_getdns_rrset *_getdns_initialized_rrset_answer(
_getdns_rrset_spc *query_rrset);
typedef struct _getdns_rrtype_iter {
_getdns_rr_iter rr_i;
_getdns_rrset *rrset;
} _getdns_rrtype_iter;
_getdns_rrtype_iter *_getdns_rrtype_iter_init(
_getdns_rrtype_iter *i, _getdns_rrset *rrset);
_getdns_rrtype_iter *_getdns_rrtype_iter_next(_getdns_rrtype_iter *i);
static inline int _getdns_rrset_has_rrs(_getdns_rrset *rrset)
{
_getdns_rrtype_iter rr_spc;
return _getdns_rrtype_iter_init(&rr_spc, rrset) != NULL;
}
typedef struct _getdns_rrsig_iter {
_getdns_rr_iter rr_i;
_getdns_rrset *rrset;
} _getdns_rrsig_iter;
_getdns_rrsig_iter *_getdns_rrsig_iter_init(
_getdns_rrsig_iter *i, _getdns_rrset *rrset);
_getdns_rrsig_iter *_getdns_rrsig_iter_next(_getdns_rrsig_iter *i);
static inline int _getdns_rrset_has_rrsigs(_getdns_rrset *rrset)
{
_getdns_rrsig_iter rrsig;
return _getdns_rrsig_iter_init(&rrsig, rrset) != NULL;
}
/* The _getdns_rrset_iter manifests an iterator of a wireformat packet that
* will return all unique rrsets within that packet in turn.
*/
typedef struct _getdns_rrset_iter {
_getdns_rrset rrset;
uint8_t name_spc[256];
size_t name_len;
_getdns_rr_iter rr_i;
} _getdns_rrset_iter;
_getdns_rrset_iter *_getdns_rrset_iter_init(_getdns_rrset_iter *i,
const uint8_t *pkt, size_t pkt_len, _getdns_section sections);
_getdns_rrset_iter *_getdns_rrset_iter_next(_getdns_rrset_iter *i);
static inline _getdns_rrset *_getdns_rrset_iter_value(_getdns_rrset_iter *i)
{ return i && i->rr_i.pos ? &i->rrset : NULL; }
static inline _getdns_rrset_iter *_getdns_rrset_iter_rewind(_getdns_rrset_iter *i)
{ return _getdns_rrset_iter_init(i, i->rrset.pkt, i->rrset.pkt_len, i->rrset.sections); }
typedef struct _getdns_rdf_iter {
const uint8_t *pkt;
const uint8_t *pkt_end;
const _getdns_rdata_def *rdd_pos;
const _getdns_rdata_def *rdd_end;
const _getdns_rdata_def *rdd_repeat;
const uint8_t *pos;
const uint8_t *end;
const uint8_t *nxt;
} _getdns_rdf_iter;
_getdns_rdf_iter *_getdns_rdf_iter_init(_getdns_rdf_iter *i,
_getdns_rr_iter *rr);
_getdns_rdf_iter *_getdns_rdf_iter_next(_getdns_rdf_iter *i);
_getdns_rdf_iter *_getdns_rdf_iter_init_at(_getdns_rdf_iter *i,
_getdns_rr_iter *rr, size_t pos);
const uint8_t *_getdns_rdf_if_or_as_decompressed(
_getdns_rdf_iter *i, uint8_t *ff_bytes, size_t *len);
#endif