msgparse.h

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/*
 * util/data/msgparse.h - parse wireformat DNS messages.
 * 
 * Copyright (c) 2007, NLnet Labs. All rights reserved.
 * 
 * This software is open source.
 * 
 * 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 name of the NLNET LABS 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 THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS 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 UTIL_DATA_MSGPARSE_H
#define UTIL_DATA_MSGPARSE_H
#include "util/storage/lruhash.h"
#include "sldns/pkthdr.h"
#include "sldns/rrdef.h"
struct sldns_buffer;
struct rrset_parse;
struct rr_parse;
struct regional;
struct edns_option;

#define PARSE_TABLE_SIZE 32
extern time_t MAX_TTL;
extern time_t MIN_TTL;
extern time_t MAX_NEG_TTL;
#define NORR_TTL 5 /* seconds */

struct msg_parse {
    uint16_t id;
    uint16_t flags;
    uint16_t qdcount;
    uint16_t ancount;
    uint16_t nscount;
    uint16_t arcount;
    size_t an_rrsets;
    size_t ns_rrsets; 
    size_t ar_rrsets;
    size_t rrset_count;

    uint8_t* qname;
    size_t qname_len;
    uint16_t qtype;
    uint16_t qclass;

    struct rrset_parse* hashtable[PARSE_TABLE_SIZE];
    
    struct rrset_parse* rrset_first;
    struct rrset_parse* rrset_last;
};

struct rrset_parse {
    struct rrset_parse* rrset_bucket_next;
    struct rrset_parse* rrset_all_next;
    hashvalue_type hash;
    sldns_pkt_section section;
    uint8_t* dname;
    size_t dname_len;
    uint16_t type;
    uint16_t rrset_class;
    uint32_t flags;
    size_t rr_count;
    size_t size;
    struct rr_parse* rr_first;
    struct rr_parse* rr_last;
    size_t rrsig_count;
    struct rr_parse* rrsig_first;
    struct rr_parse* rrsig_last;
};

struct rr_parse {
    uint8_t* ttl_data;
    int outside_packet;
    size_t size;
    struct rr_parse* next;
};

#define LABEL_IS_PTR(x) ( ((x)&0xc0) == 0xc0 )
#define PTR_OFFSET(x, y) ( ((x)&0x3f)<<8 | (y) )
#define PTR_CREATE(offset) ((uint16_t)(0xc000 | (offset)))

#define EDNS_RCODE_BADVERS  16  
#define PTR_MAX_OFFSET  0x3fff

struct edns_data {
    int edns_present;
    uint8_t ext_rcode;
    uint8_t edns_version;
    uint16_t bits;
    uint16_t udp_size;
    struct edns_option* opt_list;
};

struct edns_option {
    struct edns_option* next;
    uint16_t opt_code;
    size_t opt_len;
    uint8_t* opt_data;
};

size_t get_rdf_size(sldns_rdf_type rdf);

int parse_packet(struct sldns_buffer* pkt, struct msg_parse* msg, 
    struct regional* region);

int parse_extract_edns(struct msg_parse* msg, struct edns_data* edns,
    struct regional* region);

int parse_edns_from_pkt(struct sldns_buffer* pkt, struct edns_data* edns,
    struct regional* region);

hashvalue_type pkt_hash_rrset(struct sldns_buffer* pkt, uint8_t* dname,
    uint16_t type, uint16_t dclass, uint32_t rrset_flags);

struct rrset_parse* msgparse_hashtable_lookup(struct msg_parse* msg, 
    struct sldns_buffer* pkt, hashvalue_type h, uint32_t rrset_flags, 
    uint8_t* dname, size_t dnamelen, uint16_t type, uint16_t dclass);

void msgparse_bucket_remove(struct msg_parse* msg, struct rrset_parse* rrset);

void log_edns_opt_list(enum verbosity_value level, const char* info_str,
    struct edns_option* list);
 
#endif /* UTIL_DATA_MSGPARSE_H */