pdns/dns.hh

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #pragma once
  23 #include <boost/multi_index_container.hpp>
  24 #include <boost/multi_index/ordered_index.hpp>
  25 #include <boost/tuple/tuple_comparison.hpp>
  26 #include <boost/multi_index/key_extractors.hpp>
  27 #include <boost/multi_index/sequenced_index.hpp>
  28 #include "qtype.hh"
  29 #include "dnsname.hh"
  30 #include <time.h>
  31 #include <sys/types.h>
  32
  33 #undef BADSIG  // signal.h SIG_ERR
  34
  35 class DNSBackend;
  36 struct DNSRecord;
  37
  38 struct SOAData
  39 {
  40   SOAData() : ttl(0), serial(0), refresh(0), retry(0), expire(0), default_ttl(0), db(0), domain_id(-1) {};
  41
  42   DNSName qname;
  43   DNSName nameserver;
  44   DNSName hostmaster;
  45   uint32_t ttl;
  46   uint32_t serial;
  47   uint32_t refresh;
  48   uint32_t retry;
  49   uint32_t expire;
  50   uint32_t default_ttl;
  51   DNSBackend *db;
  52   int domain_id;
  53 };
  54
  55 class RCode
  56 {
  57 public:
  58   enum rcodes_ { NoError=0, FormErr=1, ServFail=2, NXDomain=3, NotImp=4, Refused=5, YXDomain=6, YXRRSet=7, NXRRSet=8, NotAuth=9, NotZone=10};
  59   static std::string to_s(uint8_t rcode);
  60   static std::vector<std::string> rcodes_s;
  61 };
  62
  63 class ERCode
  64 {
  65 public:
  66   enum rcodes_ { BADVERS=16, BADSIG=16, BADKEY=17, BADTIME=18, BADMODE=19, BADNAME=20, BADALG=21, BADTRUNC=22, BADCOOKIE=23 };
  67   static std::string to_s(uint8_t rcode);
  68 };
  69
  70 class Opcode
  71 {
  72 public:
  73   enum { Query=0, IQuery=1, Status=2, Notify=4, Update=5 };
  74 };
  75
  76 // enum for policy decisions, used by both auth and recursor. Not all values supported everywhere.
  77 namespace PolicyDecision { enum returnTypes { PASS=-1, DROP=-2, TRUNCATE=-3 }; };
  78
  79 //! This class represents a resource record
  80 class DNSResourceRecord
  81 {
  82 public:
  83   DNSResourceRecord() : last_modified(0), ttl(0), signttl(0), domain_id(-1), qclass(1), scopeMask(0), auth(1), disabled(0) {};
  84   ~DNSResourceRecord(){};
  85   static DNSResourceRecord fromWire(const DNSRecord& d);
  86
  87   enum Place : uint8_t {QUESTION=0, ANSWER=1, AUTHORITY=2, ADDITIONAL=3}; //!< Type describing the positioning within, say, a DNSPacket
  88
  89   void setContent(const string& content);
  90   string getZoneRepresentation(bool noDot=false) const;
  91
  92   // data
  93   DNSName qname; //!< the name of this record, for example: www.powerdns.com
  94   DNSName wildcardname;
  95   string content; //!< what this record points to. Example: 10.1.2.3
  96
  97   // Aligned on 8-byte boundries on systems where time_t is 8 bytes and int
  98   // is 4 bytes, aka modern linux on x86_64
  99   time_t last_modified; //!< For autocalculating SOA serial numbers - the backend needs to fill this in
 100
 101   uint32_t ttl; //!< Time To Live of this record
 102   uint32_t signttl; //!< If non-zero, use this TTL as original TTL in the RRSIG
 103
 104   int domain_id; //!< If a backend implements this, the domain_id of the zone this record is in
 105   QType qtype; //!< qtype of this record, ie A, CNAME, MX etc
 106   uint16_t qclass; //!< class of this record
 107
 108   uint8_t scopeMask;
 109   bool auth;
 110   bool disabled;
 111
 112   bool operator==(const DNSResourceRecord& rhs);
 113
 114   bool operator<(const DNSResourceRecord &b) const
 115   {
 116     if(qname < b.qname)
 117       return true;
 118     if(qname == b.qname)
 119       return(content < b.content);
 120     return false;
 121   }
 122 };
 123
 124 #define GCCPACKATTRIBUTE __attribute__((packed))
 125
 126 struct dnsrecordheader
 127 {
 128   uint16_t d_type;
 129   uint16_t d_class;
 130   uint32_t d_ttl;
 131   uint16_t d_clen;
 132 } GCCPACKATTRIBUTE;
 133
 134 struct EDNS0Record
 135 {
 136   uint8_t extRCode, version;
 137   uint16_t extFlags;
 138 } GCCPACKATTRIBUTE;
 139
 140 static_assert(sizeof(EDNS0Record) == 4, "EDNS0Record size must be 4");
 141
 142 #if defined(__FreeBSD__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__FreeBSD_kernel__) || defined(__NetBSD__)
 143 #include <machine/endian.h>
 144 #elif __linux__ || __GNU__
 145 # include <endian.h>
 146
 147 #else  // with thanks to <arpa/nameser.h>
 148
 149 # define LITTLE_ENDIAN   1234    /* least-significant byte first (vax, pc) */
 150 # define BIG_ENDIAN      4321    /* most-significant byte first (IBM, net) */
 151 # define PDP_ENDIAN      3412    /* LSB first in word, MSW first in long (pdp) */
 152
 153 #if defined(vax) || defined(ns32000) || defined(sun386) || defined(i386) || \
 154         defined(__i386) || defined(__ia64) || defined(__amd64) || \
 155         defined(MIPSEL) || defined(_MIPSEL) || defined(BIT_ZERO_ON_RIGHT) || \
 156         defined(__alpha__) || defined(__alpha) || \
 157         (defined(__Lynx__) && defined(__x86__))
 158 # define BYTE_ORDER      LITTLE_ENDIAN
 159 #endif
 160
 161 #if defined(sel) || defined(pyr) || defined(mc68000) || defined(sparc) || \
 162     defined(__sparc) || \
 163     defined(is68k) || defined(tahoe) || defined(ibm032) || defined(ibm370) || \
 164     defined(MIPSEB) || defined(_MIPSEB) || defined(_IBMR2) || defined(DGUX) ||\
 165     defined(apollo) || defined(__convex__) || defined(_CRAY) || \
 166     defined(__hppa) || defined(__hp9000) || \
 167     defined(__hp9000s300) || defined(__hp9000s700) || \
 168     defined(__hp3000s900) || defined(MPE) || \
 169     defined(BIT_ZERO_ON_LEFT) || defined(m68k) || \
 170         (defined(__Lynx__) && \
 171         (defined(__68k__) || defined(__sparc__) || defined(__powerpc__)))
 172 # define BYTE_ORDER      BIG_ENDIAN
 173 #endif
 174
 175 #endif
 176
 177 struct dnsheader {
 178         unsigned        id :16;         /* query identification number */
 179 #if BYTE_ORDER == BIG_ENDIAN
 180                         /* fields in third byte */
 181         unsigned        qr: 1;          /* response flag */
 182         unsigned        opcode: 4;      /* purpose of message */
 183         unsigned        aa: 1;          /* authoritative answer */
 184         unsigned        tc: 1;          /* truncated message */
 185         unsigned        rd: 1;          /* recursion desired */
 186                         /* fields in fourth byte */
 187         unsigned        ra: 1;          /* recursion available */
 188         unsigned        unused :1;      /* unused bits (MBZ as of 4.9.3a3) */
 189         unsigned        ad: 1;          /* authentic data from named */
 190         unsigned        cd: 1;          /* checking disabled by resolver */
 191         unsigned        rcode :4;       /* response code */
 192 #elif BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
 193                         /* fields in third byte */
 194         unsigned        rd :1;          /* recursion desired */
 195         unsigned        tc :1;          /* truncated message */
 196         unsigned        aa :1;          /* authoritative answer */
 197         unsigned        opcode :4;      /* purpose of message */
 198         unsigned        qr :1;          /* response flag */
 199                         /* fields in fourth byte */
 200         unsigned        rcode :4;       /* response code */
 201         unsigned        cd: 1;          /* checking disabled by resolver */
 202         unsigned        ad: 1;          /* authentic data from named */
 203         unsigned        unused :1;      /* unused bits (MBZ as of 4.9.3a3) */
 204         unsigned        ra :1;          /* recursion available */
 205 #endif
 206                         /* remaining bytes */
 207         unsigned        qdcount :16;    /* number of question entries */
 208         unsigned        ancount :16;    /* number of answer entries */
 209         unsigned        nscount :16;    /* number of authority entries */
 210         unsigned        arcount :16;    /* number of resource entries */
 211 };
 212
 213 static_assert(sizeof(dnsheader) == 12, "dnsheader size must be 12");
 214
 215 inline uint16_t * getFlagsFromDNSHeader(struct dnsheader * dh)
 216 {
 217   return (uint16_t*) (((char *) dh) + sizeof(uint16_t));
 218 }
 219
 220 #define DNS_TYPE_SIZE (2)
 221 #define DNS_CLASS_SIZE (2)
 222 #define DNS_TTL_SIZE (4)
 223 #define DNS_RDLENGTH_SIZE (2)
 224 #define EDNS_EXTENDED_RCODE_SIZE (1)
 225 #define EDNS_VERSION_SIZE (1)
 226 #define EDNS_OPTION_CODE_SIZE (2)
 227 #define EDNS_OPTION_LENGTH_SIZE (2)
 228
 229 #if BYTE_ORDER == BIG_ENDIAN
 230 #define FLAGS_RD_OFFSET (8)
 231 #define FLAGS_CD_OFFSET (12)
 232 #elif BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
 233 #define FLAGS_RD_OFFSET (0)
 234 #define FLAGS_CD_OFFSET (12)
 235 #endif
 236
 237 extern time_t s_starttime;
 238
 239 uint32_t hashQuestion(const char* packet, uint16_t len, uint32_t init);
 240
 241 struct TSIGTriplet
 242 {
 243   DNSName name, algo;
 244   string secret;
 245 };
 246
 247 string &attodot(string &str);  //!< for when you need to insert an email address in the SOA