dns_common.h

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#ifndef _DNS_COMMON_H
#define _DNS_COMMON_H
 
//Dependencies
#include "core/net.h"
 
//Maximum recursion limit when parsing domain names
#ifndef DNS_NAME_MAX_RECURSION
   #define DNS_NAME_MAX_RECURSION 4
#elif (DNS_NAME_MAX_RECURSION < 1 || DNS_NAME_MAX_RECURSION > 8)
   #error DNS_NAME_MAX_RECURSION parameter is not valid
#endif
 
//Maximum size of DNS messages
#define DNS_MESSAGE_MAX_SIZE 512
//Maximum size of names
#define DNS_NAME_MAX_SIZE 255
//Maximum size of labels
#define DNS_LABEL_MAX_SIZE 63
 
//Maximum length of reverse DNS names (IPv4)
#define DNS_MAX_IPV4_REVERSE_NAME_LEN 15
//Maximum length of reverse DNS names (IPv6)
#define DNS_MAX_IPV6_REVERSE_NAME_LEN 63
 
//DNS port number
#define DNS_PORT 53
 
//Label compression tag
#define DNS_COMPRESSION_TAG 0xC0
 
//Macro definition
#define DNS_GET_QUESTION(message, offset) (DnsQuestion *) ((uint8_t *) (message) + (offset))
#define DNS_GET_RESOURCE_RECORD(message, offset) (DnsResourceRecord *) ((uint8_t *) (message) + (offset))
 
#define DNS_SET_NSEC_BITMAP(bitmap, type) bitmap[(type) / 8] |= 0x80 >> ((type) % 8)
#define DNS_CLR_NSEC_BITMAP(bitmap, type) bitmap[(type) / 8] &= ~(0x80 >> ((type) % 8))
 
//C++ guard
#ifdef __cplusplus
extern "C" {
#endif
 
 
typedef enum
{
   DNS_OPCODE_QUERY  = 0, 
   DNS_OPCODE_IQUERY = 1, 
   DNS_OPCODE_STATUS = 2, 
   DNS_OPCODE_NOTIFY = 4, 
   DNS_OPCODE_UPDATE = 5  
} DnsOpcode;
 
 
typedef enum
{
   DNS_RCODE_NOERROR   = 0,  
   DNS_RCODE_FORMERR   = 1,  
   DNS_RCODE_SERVFAIL  = 2,  
   DNS_RCODE_NXDOMAIN  = 3,  
   DNS_RCODE_NOTIMP    = 4,  
   DNS_RCODE_REFUSED   = 5,  
   DNS_RCODE_YXDOMAIN  = 6,  
   DNS_RCODE_YXRRSET   = 7,  
   DNS_RCODE_NXRRSET   = 8,  
   DNS_RCODE_NOTAUTH   = 9,  
   DNS_RCODE_NOTZONE   = 10, 
   DNS_RCODE_BADVERS   = 16, 
   DNS_RCODE_BADSIG    = 16, 
   DNS_RCODE_BADKEY    = 17, 
   DNS_RCODE_BADTIME   = 18, 
   DNS_RCODE_BADMODE   = 19, 
   DNS_RCODE_BADNAME   = 20, 
   DNS_RCODE_BADALG    = 21, 
   DNS_RCODE_BADTRUC   = 22, 
   DNS_RCODE_BADCOOKIE = 23  
} DnsResponseCode;
 
 
typedef enum
{
   DNS_RR_CLASS_IN  = 1,  
   DNS_RR_CLASS_CH  = 3,  
   DNS_RR_CLASS_HS  = 4,  
   DNS_RR_CLASS_ANY = 255 
} DnsResourceRecordClass;
 
 
typedef enum
{
   DNS_RR_TYPE_A     = 1,   
   DNS_RR_TYPE_NS    = 2,   
   DNS_RR_TYPE_CNAME = 5,   
   DNS_RR_TYPE_SOA   = 6,   
   DNS_RR_TYPE_WKS   = 11,  
   DNS_RR_TYPE_PTR   = 12,  
   DNS_RR_TYPE_HINFO = 13,  
   DNS_RR_TYPE_MINFO = 14,  
   DNS_RR_TYPE_MX    = 15,  
   DNS_RR_TYPE_TXT   = 16,  
   DNS_RR_TYPE_AAAA  = 28,  
   DNS_RR_TYPE_NB    = 32,  
   DNS_RR_TYPE_SRV   = 33,  
   DNS_RR_TYPE_NAPTR = 35,  
   DNS_RR_TYPE_NSEC  = 47,  
   DNS_RR_TYPE_EUI48 = 108, 
   DNS_RR_TYPE_EUI64 = 109, 
   DNS_RR_TYPE_AXFR  = 252, 
   DNS_RR_TYPE_ANY   = 255, 
   DNS_RR_TYPE_URI   = 256  
} DnsResourceRecordType;
 
 
//CodeWarrior or Win32 compiler?
#if defined(__CWCC__) || defined(_WIN32)
   #pragma pack(push, 1)
#endif
 
 
typedef __packed_struct
{
   uint16_t id;         //0-1
#if defined(_CPU_BIG_ENDIAN) && !defined(__ICCRX__)
   uint8_t qr : 1;      //2
   uint8_t opcode : 4;
   uint8_t aa : 1;
   uint8_t tc : 1;
   uint8_t rd : 1;
   uint8_t ra : 1;      //3
   uint8_t z : 3;
   uint8_t rcode : 4;
#else
   uint8_t rd : 1;      //2
   uint8_t tc : 1;
   uint8_t aa : 1;
   uint8_t opcode : 4;
   uint8_t qr : 1;
   uint8_t rcode : 4;   //3
   uint8_t z : 3;
   uint8_t ra : 1;
#endif
   uint16_t qdcount;    //4-5
   uint16_t ancount;    //6-7
   uint16_t nscount;    //8-9
   uint16_t arcount;    //10-11
   uint8_t questions[]; //12
} DnsHeader;
 
 
typedef __packed_struct
{
   uint16_t qtype;
   uint16_t qclass;
} DnsQuestion;
 
 
typedef __packed_struct
{
   uint16_t rtype;    //0-1
   uint16_t rclass;   //2-3
   uint32_t ttl;      //4-7
   uint16_t rdlength; //8-9
   uint8_t rdata[];   //10
} DnsResourceRecord;
 
 
typedef __packed_struct
{
   uint16_t rtype;    //0-1
   uint16_t rclass;   //2-3
   uint32_t ttl;      //4-7
   uint16_t rdlength; //8-9
   uint8_t rdata[4];  //10-13
} DnsIpv4AddrResourceRecord;
 
 
typedef __packed_struct
{
   uint16_t rtype;    //0-1
   uint16_t rclass;   //2-3
   uint32_t ttl;      //4-7
   uint16_t rdlength; //8-9
   uint8_t rdata[16]; //10-25
} DnsIpv6AddrResourceRecord;
 
 
typedef __packed_struct
{
   uint16_t rtype;    //0-1
   uint16_t rclass;   //2-3
   uint32_t ttl;      //4-7
   uint16_t rdlength; //8-9
   uint16_t priority; //10-11
   uint16_t weight;   //12-13
   uint16_t port;     //14-15
   uint8_t target[];  //16
} DnsSrvResourceRecord;
 
 
//CodeWarrior or Win32 compiler?
#if defined(__CWCC__) || defined(_WIN32)
   #pragma pack(pop)
#endif
 
//DNS related functions
size_t dnsEncodeName(const char_t *src, uint8_t *dest);
 
size_t dnsParseName(const DnsHeader *message, size_t length, size_t pos,
   char_t *dest, uint_t level);
 
int_t dnsCompareName(const DnsHeader *message, size_t length, size_t pos,
   const char_t *name, uint_t level);
 
int_t dnsCompareEncodedName(const DnsHeader *message1, size_t length1,
   size_t pos1, const DnsHeader *message2, size_t length2, size_t pos2,
   uint_t level);
 
void dnsGenerateIpv4ReverseName(Ipv4Addr ipv4Addr, char_t *buffer);
void dnsGenerateIpv6ReverseName(const Ipv6Addr *ipv6Addr, char_t *buffer);
 
//C++ guard
#ifdef __cplusplus
}
#endif
 
#endif