1 /* 2 * dns.h -- DNS definitions. 3 * 4 * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. 5 * 6 * See LICENSE for the license. 7 * 8 */ 9 10 #ifndef _DNS_H_ 11 #define _DNS_H_ 12 13 enum rr_section { 14 QUESTION_SECTION, 15 ANSWER_SECTION, 16 AUTHORITY_SECTION, 17 /* 18 * Use a split authority section to ensure that optional 19 * NS RRsets in the response can be omitted. 20 */ 21 OPTIONAL_AUTHORITY_SECTION, 22 ADDITIONAL_SECTION, 23 /* 24 * Use a split additional section to ensure A records appear 25 * before any AAAA records (this is recommended practice to 26 * avoid truncating the additional section for IPv4 clients 27 * that do not specify EDNS0), and AAAA records before other 28 * types of additional records (such as X25 and ISDN). 29 * Encode_answer sets the ARCOUNT field of the response packet 30 * correctly. 31 */ 32 ADDITIONAL_A_SECTION = ADDITIONAL_SECTION, 33 ADDITIONAL_AAAA_SECTION, 34 ADDITIONAL_OTHER_SECTION, 35 36 RR_SECTION_COUNT 37 }; 38 typedef enum rr_section rr_section_type; 39 40 /* Possible OPCODE values */ 41 #define OPCODE_QUERY 0 /* a standard query (QUERY) */ 42 #define OPCODE_IQUERY 1 /* an inverse query (IQUERY) */ 43 #define OPCODE_STATUS 2 /* a server status request (STATUS) */ 44 #define OPCODE_NOTIFY 4 /* NOTIFY */ 45 #define OPCODE_UPDATE 5 /* Dynamic update */ 46 47 /* Possible RCODE values */ 48 #define RCODE_OK 0 /* No error condition */ 49 #define RCODE_FORMAT 1 /* Format error */ 50 #define RCODE_SERVFAIL 2 /* Server failure */ 51 #define RCODE_NXDOMAIN 3 /* Name Error */ 52 #define RCODE_IMPL 4 /* Not implemented */ 53 #define RCODE_REFUSE 5 /* Refused */ 54 #define RCODE_YXDOMAIN 6 /* name should not exist */ 55 #define RCODE_YXRRSET 7 /* rrset should not exist */ 56 #define RCODE_NXRRSET 8 /* rrset does not exist */ 57 #define RCODE_NOTAUTH 9 /* server not authoritative */ 58 #define RCODE_NOTZONE 10 /* name not inside zone */ 59 60 /* Standardized NSD return code. Partially maps to DNS RCODE values. */ 61 enum nsd_rc 62 { 63 /* Discard the client request. */ 64 NSD_RC_DISCARD = -1, 65 /* OK, continue normal processing. */ 66 NSD_RC_OK = RCODE_OK, 67 /* Return the appropriate error code to the client. */ 68 NSD_RC_FORMAT = RCODE_FORMAT, 69 NSD_RC_SERVFAIL = RCODE_SERVFAIL, 70 NSD_RC_NXDOMAIN = RCODE_NXDOMAIN, 71 NSD_RC_IMPL = RCODE_IMPL, 72 NSD_RC_REFUSE = RCODE_REFUSE, 73 NSD_RC_NOTAUTH = RCODE_NOTAUTH 74 }; 75 typedef enum nsd_rc nsd_rc_type; 76 77 /* RFC1035 */ 78 #define CLASS_IN 1 /* Class IN */ 79 #define CLASS_CS 2 /* Class CS */ 80 #define CLASS_CH 3 /* Class CHAOS */ 81 #define CLASS_HS 4 /* Class HS */ 82 #define CLASS_NONE 254 /* Class NONE rfc2136 */ 83 #define CLASS_ANY 255 /* Class ANY */ 84 85 #define TYPE_A 1 /* a host address */ 86 #define TYPE_NS 2 /* an authoritative name server */ 87 #define TYPE_MD 3 /* a mail destination (Obsolete - use MX) */ 88 #define TYPE_MF 4 /* a mail forwarder (Obsolete - use MX) */ 89 #define TYPE_CNAME 5 /* the canonical name for an alias */ 90 #define TYPE_SOA 6 /* marks the start of a zone of authority */ 91 #define TYPE_MB 7 /* a mailbox domain name (EXPERIMENTAL) */ 92 #define TYPE_MG 8 /* a mail group member (EXPERIMENTAL) */ 93 #define TYPE_MR 9 /* a mail rename domain name (EXPERIMENTAL) */ 94 #define TYPE_NULL 10 /* a null RR (EXPERIMENTAL) */ 95 #define TYPE_WKS 11 /* a well known service description */ 96 #define TYPE_PTR 12 /* a domain name pointer */ 97 #define TYPE_HINFO 13 /* host information */ 98 #define TYPE_MINFO 14 /* mailbox or mail list information */ 99 #define TYPE_MX 15 /* mail exchange */ 100 #define TYPE_TXT 16 /* text strings */ 101 #define TYPE_RP 17 /* RFC1183 */ 102 #define TYPE_AFSDB 18 /* RFC1183 */ 103 #define TYPE_X25 19 /* RFC1183 */ 104 #define TYPE_ISDN 20 /* RFC1183 */ 105 #define TYPE_RT 21 /* RFC1183 */ 106 #define TYPE_NSAP 22 /* RFC1706 */ 107 108 #define TYPE_SIG 24 /* 2535typecode */ 109 #define TYPE_KEY 25 /* 2535typecode */ 110 #define TYPE_PX 26 /* RFC2163 */ 111 112 #define TYPE_AAAA 28 /* ipv6 address */ 113 #define TYPE_LOC 29 /* LOC record RFC1876 */ 114 #define TYPE_NXT 30 /* 2535typecode */ 115 116 #define TYPE_SRV 33 /* SRV record RFC2782 */ 117 118 #define TYPE_NAPTR 35 /* RFC2915 */ 119 #define TYPE_KX 36 /* RFC2230 Key Exchange Delegation Record */ 120 #define TYPE_CERT 37 /* RFC2538 */ 121 122 #define TYPE_A6 38 /* RFC2874 */ 123 124 #define TYPE_DNAME 39 /* RFC2672 */ 125 126 #define TYPE_OPT 41 /* Pseudo OPT record... */ 127 #define TYPE_APL 42 /* RFC3123 */ 128 #define TYPE_DS 43 /* RFC 4033, 4034, and 4035 */ 129 #define TYPE_SSHFP 44 /* SSH Key Fingerprint */ 130 #define TYPE_IPSECKEY 45 /* public key for ipsec use. RFC 4025 */ 131 132 #define TYPE_RRSIG 46 /* RFC 4033, 4034, and 4035 */ 133 #define TYPE_NSEC 47 /* RFC 4033, 4034, and 4035 */ 134 #define TYPE_DNSKEY 48 /* RFC 4033, 4034, and 4035 */ 135 #define TYPE_DHCID 49 /* RFC4701 DHCP information */ 136 #define TYPE_NSEC3 50 /* NSEC3, secure denial, prevents zonewalking */ 137 #define TYPE_NSEC3PARAM 51 /* NSEC3PARAM at zone apex nsec3 parameters */ 138 #define TYPE_TLSA 52 /* RFC 6698 */ 139 #define TYPE_SMIMEA 53 /* RFC 8162 */ 140 #define TYPE_CDS 59 /* RFC 7344 */ 141 #define TYPE_CDNSKEY 60 /* RFC 7344 */ 142 #define TYPE_OPENPGPKEY 61 /* RFC 7929 */ 143 #define TYPE_CSYNC 62 /* RFC 7477 */ 144 145 #define TYPE_SPF 99 /* RFC 4408 */ 146 147 #define TYPE_NID 104 /* RFC 6742 */ 148 #define TYPE_L32 105 /* RFC 6742 */ 149 #define TYPE_L64 106 /* RFC 6742 */ 150 #define TYPE_LP 107 /* RFC 6742 */ 151 #define TYPE_EUI48 108 /* RFC 7043 */ 152 #define TYPE_EUI64 109 /* RFC 7043 */ 153 154 #define TYPE_TSIG 250 155 #define TYPE_IXFR 251 156 #define TYPE_AXFR 252 157 #define TYPE_MAILB 253 /* A request for mailbox-related records (MB, MG or MR) */ 158 #define TYPE_MAILA 254 /* A request for mail agent RRs (Obsolete - see MX) */ 159 #define TYPE_ANY 255 /* any type (wildcard) */ 160 #define TYPE_URI 256 /* RFC 7553 */ 161 #define TYPE_CAA 257 /* RFC 6844 */ 162 #define TYPE_AVC 258 163 164 #define TYPE_DLV 32769 /* RFC 4431 */ 165 #define PSEUDO_TYPE_DLV RRTYPE_DESCRIPTORS_LENGTH 166 167 #define MAXLABELLEN 63 168 #define MAXDOMAINLEN 255 169 170 #define MAXRDATALEN 64 /* This is more than enough, think multiple TXT. */ 171 #define MAX_RDLENGTH 65535 172 173 /* Maximum size of a single RR. */ 174 #define MAX_RR_SIZE \ 175 (MAXDOMAINLEN + sizeof(uint32_t) + 4*sizeof(uint16_t) + MAX_RDLENGTH) 176 177 #define IP4ADDRLEN (32/8) 178 #define IP6ADDRLEN (128/8) 179 #define EUI48ADDRLEN (48/8) 180 #define EUI64ADDRLEN (64/8) 181 182 #define NSEC3_HASH_LEN 20 183 184 /* 185 * The different types of RDATA wireformat data. 186 */ 187 enum rdata_wireformat 188 { 189 RDATA_WF_COMPRESSED_DNAME, /* Possibly compressed domain name. */ 190 RDATA_WF_UNCOMPRESSED_DNAME, /* Uncompressed domain name. */ 191 RDATA_WF_LITERAL_DNAME, /* Literal (not downcased) dname. */ 192 RDATA_WF_BYTE, /* 8-bit integer. */ 193 RDATA_WF_SHORT, /* 16-bit integer. */ 194 RDATA_WF_LONG, /* 32-bit integer. */ 195 RDATA_WF_TEXT, /* Text string. */ 196 RDATA_WF_TEXTS, /* Text string sequence. */ 197 RDATA_WF_A, /* 32-bit IPv4 address. */ 198 RDATA_WF_AAAA, /* 128-bit IPv6 address. */ 199 RDATA_WF_BINARY, /* Binary data (unknown length). */ 200 RDATA_WF_BINARYWITHLENGTH, /* Binary data preceded by 1 byte length */ 201 RDATA_WF_APL, /* APL data. */ 202 RDATA_WF_IPSECGATEWAY, /* IPSECKEY gateway ip4, ip6 or dname. */ 203 RDATA_WF_ILNP64, /* 64-bit uncompressed IPv6 address. */ 204 RDATA_WF_EUI48, /* 48-bit address. */ 205 RDATA_WF_EUI64, /* 64-bit address. */ 206 RDATA_WF_LONG_TEXT /* Long (>255) text string. */ 207 }; 208 typedef enum rdata_wireformat rdata_wireformat_type; 209 210 /* 211 * The different types of RDATA that can appear in the zone file. 212 */ 213 enum rdata_zoneformat 214 { 215 RDATA_ZF_DNAME, /* Domain name. */ 216 RDATA_ZF_LITERAL_DNAME, /* DNS name (not lowercased domain name). */ 217 RDATA_ZF_TEXT, /* Text string. */ 218 RDATA_ZF_TEXTS, /* Text string sequence. */ 219 RDATA_ZF_BYTE, /* 8-bit integer. */ 220 RDATA_ZF_SHORT, /* 16-bit integer. */ 221 RDATA_ZF_LONG, /* 32-bit integer. */ 222 RDATA_ZF_A, /* 32-bit IPv4 address. */ 223 RDATA_ZF_AAAA, /* 128-bit IPv6 address. */ 224 RDATA_ZF_RRTYPE, /* RR type. */ 225 RDATA_ZF_ALGORITHM, /* Cryptographic algorithm. */ 226 RDATA_ZF_CERTIFICATE_TYPE, 227 RDATA_ZF_PERIOD, /* Time period. */ 228 RDATA_ZF_TIME, 229 RDATA_ZF_BASE64, /* Base-64 binary data. */ 230 RDATA_ZF_BASE32, /* Base-32 binary data. */ 231 RDATA_ZF_HEX, /* Hexadecimal binary data. */ 232 RDATA_ZF_HEX_LEN, /* Hexadecimal binary data. Skip initial length byte. */ 233 RDATA_ZF_NSAP, /* NSAP. */ 234 RDATA_ZF_APL, /* APL. */ 235 RDATA_ZF_IPSECGATEWAY, /* IPSECKEY gateway ip4, ip6 or dname. */ 236 RDATA_ZF_SERVICES, /* Protocol and port number bitmap. */ 237 RDATA_ZF_NXT, /* NXT type bitmap. */ 238 RDATA_ZF_NSEC, /* NSEC type bitmap. */ 239 RDATA_ZF_LOC, /* Location data. */ 240 RDATA_ZF_ILNP64, /* 64-bit uncompressed IPv6 address. */ 241 RDATA_ZF_EUI48, /* EUI48 address. */ 242 RDATA_ZF_EUI64, /* EUI64 address. */ 243 RDATA_ZF_LONG_TEXT, /* Long (>255) text string. */ 244 RDATA_ZF_TAG, /* Text string without quotes. */ 245 RDATA_ZF_UNKNOWN /* Unknown data. */ 246 }; 247 typedef enum rdata_zoneformat rdata_zoneformat_type; 248 249 struct rrtype_descriptor 250 { 251 uint16_t type; /* RR type */ 252 const char *name; /* Textual name. */ 253 int token; /* Parser token. */ 254 uint32_t minimum; /* Minimum number of RDATAs. */ 255 uint32_t maximum; /* Maximum number of RDATAs. */ 256 uint8_t wireformat[MAXRDATALEN]; /* rdata_wireformat_type */ 257 uint8_t zoneformat[MAXRDATALEN]; /* rdata_zoneformat_type */ 258 }; 259 typedef struct rrtype_descriptor rrtype_descriptor_type; 260 261 /* 262 * Indexed by type. The special type "0" can be used to get a 263 * descriptor for unknown types (with one binary rdata). 264 * 265 * AVC + 1 266 */ 267 #define RRTYPE_DESCRIPTORS_LENGTH (TYPE_AVC + 1) 268 rrtype_descriptor_type *rrtype_descriptor_by_name(const char *name); 269 rrtype_descriptor_type *rrtype_descriptor_by_type(uint16_t type); 270 271 const char *rrtype_to_string(uint16_t rrtype); 272 273 /* 274 * Lookup the type in the ztypes lookup table. If not found, check if 275 * the type uses the "TYPExxx" notation for unknown types. 276 * 277 * Return 0 if no type matches. 278 */ 279 uint16_t rrtype_from_string(const char *name); 280 281 const char *rrclass_to_string(uint16_t rrclass); 282 uint16_t rrclass_from_string(const char *name); 283 284 #ifdef __cplusplus 285 inline rr_section_type 286 operator++(rr_section_type &lhs) 287 { 288 lhs = (rr_section_type) ((int) lhs + 1); 289 return lhs; 290 } 291 #endif /* __cplusplus */ 292 293 #endif /* _DNS_H_ */ 294