/* * $Id$ * Copyright (c) 2016-2020 Chung, Hyung-Hwan. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. 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. THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAfRRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR 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 _MIO_DNS_H_ #define _MIO_DNS_H_ #include #include #define MIO_DNS_PORT (53) enum mio_dns_opcode_t { MIO_DNS_OPCODE_QUERY = 0, /* standard query */ MIO_DNS_OPCODE_IQUERY = 1, /* inverse query */ MIO_DNS_OPCODE_STATUS = 2, /* status request */ /* 3 unassigned */ MIO_DNS_OPCODE_NOTIFY = 4, MIO_DNS_OPCODE_UPDATE = 5 }; typedef enum mio_dns_opcode_t mio_dns_opcode_t; enum mio_dns_rcode_t { MIO_DNS_RCODE_NOERROR = 0, MIO_DNS_RCODE_FORMERR = 1, /* format error */ MIO_DNS_RCODE_SERVFAIL = 2, /* server failure */ MIO_DNS_RCODE_NXDOMAIN = 3, /* non-existent domain */ MIO_DNS_RCODE_NOTIMPL = 4, /* not implemented */ MIO_DNS_RCODE_REFUSED = 5, /* query refused */ MIO_DNS_RCODE_YXDOMAIN = 6, /* name exists when it should not */ MIO_DNS_RCODE_YXRRSET = 7, /* RR set exists when it should not */ MIO_DNS_RCODE_NXRRSET = 8, /* RR set exists when it should not */ MIO_DNS_RCODE_NOTAUTH = 9, /* not authorized or server not authoritative for zone*/ MIO_DNS_RCODE_NOTZONE = 10, /* name not contained in zone */ /* the standard rcode field is 4 bit long. so the max is 15. */ /* items belows require EDNS0 */ MIO_DNS_RCODE_BADVERS = 16, MIO_DNS_RCODE_BADSIG = 17, MIO_DNS_RCODE_BADTIME = 18, MIO_DNS_RCODE_BADMODE = 19, MIO_DNS_RCODE_BADNAME = 20, MIO_DNS_RCODE_BADALG = 21, MIO_DNS_RCODE_BADTRUNC = 22, MIO_DNS_RCODE_BADCOOKIE = 23 }; typedef enum mio_dns_rcode_t mio_dns_rcode_t; enum mio_dns_rrt_t { /* * [RFC1035] * TYPE fields are used in resource records. Note that these types are a * subset of QTYPEs. */ MIO_DNS_RRT_A = 1, MIO_DNS_RRT_NS = 2, MIO_DNS_RRT_MD = 3, /* mail destination. RFC973 replaced this with MX*/ MIO_DNS_RRT_MF = 4, /* mail forwarder. RFC973 replaced this with MX */ MIO_DNS_RRT_CNAME = 5, MIO_DNS_RRT_SOA = 6, MIO_DNS_RRT_MB = 7, /* kind of obsoleted. RFC1035, RFC2505 */ MIO_DNS_RRT_MG = 8, /* kind of obsoleted. RFC1035, RFC2505 */ MIO_DNS_RRT_MR = 9, /* kind of obsoleted. RFC1035, RFC2505 */ MIO_DNS_RRT_NULL = 10, MIO_DNS_RRT_PTR = 12, MIO_DNS_RRT_MINFO = 15, /* kind of obsoleted. RFC1035, RFC2505 */ MIO_DNS_RRT_MX = 15, MIO_DNS_RRT_TXT = 16, MIO_DNS_RRT_AAAA = 28, MIO_DNS_RRT_EID = 31, MIO_DNS_RRT_SRV = 33, MIO_DNS_RRT_OPT = 41, MIO_DNS_RRT_RRSIG = 46, /* * [RFC1035] * QTYPE fields appear in the question part of a query. QTYPES are a * superset of TYPEs, hence all TYPEs are valid QTYPEs. In addition, the * following QTYPEs are defined: */ MIO_DNS_RRT_Q_AFXR = 252, /* A request for a transfer of an entire zone */ MIO_DNS_RRT_Q_MAILB = 253, /* A request for mailbox-related records (MB, MG or MR) */ MIO_DNS_RRT_Q_MAILA = 254, /* A request for mail agent RRs (Obsolete - see MX) */ MIO_DNS_RRT_Q_ANY = 255 /* A request for all records */ }; typedef enum mio_dns_rrt_t mio_dns_rrt_t; /* * CLASS fields appear in resource records. The following CLASS mnemonics * and values are defined: */ enum mio_dns_rrc_t { MIO_DNS_RRC_IN = 1, /* internet */ MIO_DNS_RRC_CH = 3, /* chaos */ MIO_DNS_RRC_HS = 4, /* Hesiod [Dyer 87] */ MIO_DNS_RRC_NONE = 254, /* * * QCLASS fields appear in the question section of a query. QCLASS values * are a superset of CLASS values; every CLASS is a valid QCLASS. In * addition to CLASS values, the following QCLASSes are defined: */ MIO_DNS_RRC_Q_ANY = 255 }; typedef enum mio_dns_rrc_t mio_dns_rrc_t; enum mio_dns_eopt_code_t { MIO_DNS_EOPT_NSID = 3, MIO_DNS_EOPT_DAU = 5, MIO_DNS_EOPT_DHU = 6, MIO_DNS_EOPT_N3U = 7, MIO_DNS_EOPT_ECS = 8, MIO_DNS_EOPT_EXPIRE = 9, MIO_DNS_EOPT_COOKIE = 10, MIO_DNS_EOPT_TCPKEEPALIVE = 11, MIO_DNS_EOPT_PADDING = 12, MIO_DNS_EOPT_CHAIN = 13, MIO_DNS_EOPT_KEYTAG = 14, }; typedef enum mio_dns_eopt_code_t mio_dns_eopt_code_t; /* dns message preamble */ typedef struct mio_dns_msg_t mio_dns_msg_t; struct mio_dns_msg_t { mio_oow_t msglen; mio_oow_t ednsrrtroff; /* offset to trailing data after the name in the dns0 RR*/ mio_oow_t pktlen; mio_oow_t pktalilen; }; #include struct mio_dns_pkt_t /* dns packet header */ { mio_uint16_t id; #if defined(MIO_ENDIAN_BIG) mio_uint16_t qr: 1; /* query(0), answer(1) */ mio_uint16_t opcode: 4; /* operation type */ mio_uint16_t aa: 1; /* authoritative answer */ mio_uint16_t tc: 1; /* truncated. response too large for UDP */ mio_uint16_t rd: 1; /* recursion desired */ mio_uint16_t ra: 1; /* recursion available */ mio_uint16_t unused_1: 1; mio_uint16_t ad: 1; /* authentication data - dnssec */ mio_uint16_t cd: 1; /* checking disabled - dnssec */ mio_uint16_t rcode: 4; /* reply code - for reply only */ #else mio_uint16_t rd: 1; mio_uint16_t tc: 1; mio_uint16_t aa: 1; mio_uint16_t opcode: 4; mio_uint16_t qr: 1; mio_uint16_t rcode: 4; mio_uint16_t cd: 1; mio_uint16_t ad: 1; mio_uint16_t unused_1: 1; mio_uint16_t ra: 1; #endif mio_uint16_t qdcount; /* number of questions */ mio_uint16_t ancount; /* number of answers (answer part) */ mio_uint16_t nscount; /* number of name servers (authority part. only NS types) */ mio_uint16_t arcount; /* number of additional resource (additional part) */ }; typedef struct mio_dns_pkt_t mio_dns_pkt_t; struct mio_dns_pkt_alt_t { mio_uint16_t id; mio_uint16_t flags; mio_uint16_t rrcount[4]; }; typedef struct mio_dns_pkt_alt_t mio_dns_pkt_alt_t; /* question * name, qtype, qclass * answer * name, qtype, qclass, ttl, rlength, rdata */ /* trailing part after the domain name in a resource record in a question */ struct mio_dns_qrtr_t { /* qname upto 64 bytes */ mio_uint16_t qtype; mio_uint16_t qclass; }; typedef struct mio_dns_qrtr_t mio_dns_qrtr_t; /* trailing part after the domain name in a resource record in an answer */ struct mio_dns_rrtr_t { /* qname upto 64 bytes */ mio_uint16_t rrtype; mio_uint16_t rrclass; mio_uint32_t ttl; mio_uint16_t dlen; /* data length */ /* actual data if if dlen > 0 */ }; typedef struct mio_dns_rrtr_t mio_dns_rrtr_t; struct mio_dns_eopt_t { mio_uint16_t code; mio_uint16_t dlen; /* actual data if if dlen > 0 */ }; typedef struct mio_dns_eopt_t mio_dns_eopt_t; #include /* ---------------------------------------------------------------- */ /* #define MIO_DNS_HEADER_MAKE_FLAGS(qr,opcode,aa,tc,rd,ra,ad,cd,rcode) \ ((((qr) & 0x01) << 15) | (((opcode) & 0x0F) << 14) | (((aa) & 0x01) << 10) | (((tc) & 0x01) << 9) | \ (((rd) & 0x01) << 8) | (((ra) & 0x01) << 7) | (((ad) & 0x01) << 5) | (((cd) & 0x01) << 4) | ((rcode) & 0x0F)) */ /* breakdown of the dns message id and flags. it excludes rr count fields.*/ struct mio_dns_bhdr_t { mio_int32_t id; mio_uint8_t qr; /* query(0), answer(1) */ mio_uint8_t opcode; /* operation type */ mio_uint8_t aa; /* authoritative answer */ mio_uint8_t tc; /* truncated. response too large for UDP */ mio_uint8_t rd; /* recursion desired */ mio_uint8_t ra; /* recursion available */ mio_uint8_t ad; /* authentication data - dnssec */ mio_uint8_t cd; /* checking disabled - dnssec */ mio_uint8_t rcode; /* reply code - for reply only */ }; typedef struct mio_dns_bhdr_t mio_dns_bhdr_t; /* breakdown of question record */ struct mio_dns_bqr_t { mio_bch_t* qname; mio_uint16_t qtype; mio_uint16_t qclass; }; typedef struct mio_dns_bqr_t mio_dns_bqr_t; enum mio_dns_rr_part_t { MIO_DNS_RR_PART_ANSWER, MIO_DNS_RR_PART_AUTHORITY, MIO_DNS_RR_PART_ADDITIONAL }; typedef enum mio_dns_rr_part_t mio_dns_rr_part_t; /* breakdown of resource record */ struct mio_dns_brr_t { mio_dns_rr_part_t part; mio_bch_t* rrname; mio_uint16_t rrtype; mio_uint16_t rrclass; mio_uint32_t ttl; mio_uint16_t dlen; void* dptr; }; typedef struct mio_dns_brr_t mio_dns_brr_t; #if 0 /* A RDATA */ struct mio_dns_brrd_a_t { }; typedef struct mio_dns_brrd_a_t mio_dns_brrd_a_t; /* 3.3.1 CNAME RDATA format */ struct mio_dns_brrd_cname_t { }; typedef struct mio_dns_brrd_cname_t mio_dns_brc_cname_t; #endif /* 3.3.9 MX RDATA format */ struct mio_dns_brrd_mx_t { mio_uint16_t preference; mio_bch_t* exchange; }; typedef struct mio_dns_brrd_mx_t mio_dns_brrd_mx_t; /* 3.3.13. SOA RDATA format */ struct mio_dns_brrd_soa_t { mio_bch_t* mname; mio_bch_t* rname; mio_uint32_t serial; mio_uint32_t refresh; mio_uint32_t retry; mio_uint32_t expire; mio_uint32_t minimum; }; typedef struct mio_dns_brrd_soa_t mio_dns_brrd_soa_t; struct mio_dns_beopt_t { mio_uint16_t code; mio_uint16_t dlen; void* dptr; }; typedef struct mio_dns_beopt_t mio_dns_beopt_t; /* the full rcode must be given. the macro takes the upper 8 bits */ #define MIO_DNS_EDNS_MAKE_TTL(rcode,version,dnssecok) ((((((mio_uint32_t)rcode) >> 4) & 0xFF) << 24) | (((mio_uint32_t)version & 0xFF) << 16) | (((mio_uint32_t)dnssecok & 0x1) << 15)) struct mio_dns_bedns_t { mio_uint16_t uplen; /* udp payload len - will be placed in the qclass field of RR. */ /* the ttl field(32 bits) of RR holds extended rcode, version, dnssecok */ mio_uint8_t version; mio_uint8_t dnssecok; mio_oow_t beonum; /* option count */ mio_dns_beopt_t* beoptr; }; typedef struct mio_dns_bedns_t mio_dns_bedns_t; /* ---------------------------------------------------------------- */ typedef struct mio_svc_dns_t mio_svc_dns_t; /* server service */ typedef struct mio_svc_dnc_t mio_svc_dnc_t; /* client service */ typedef struct mio_svc_dnr_t mio_svc_dnr_t; /* recursor service */ typedef void (*mio_svc_dnc_on_done_t) ( mio_svc_dnc_t* dnc, mio_dns_msg_t* reqmsg, mio_errnum_t status, const void* data, mio_oow_t len ); typedef void (*mio_svc_dnc_on_resolve_t) ( mio_svc_dnc_t* dnc, mio_dns_msg_t* reqmsg, mio_errnum_t status, const void* data, mio_oow_t len ); enum mio_svc_dnc_send_flag_t { MIO_SVC_DNC_SEND_FLAG_PREFER_TCP = (1 << 0), MIO_SVC_DNC_SEND_FLAG_TCP_IF_TC = (1 << 1), // retry over tcp if the truncated bit is set in an answer over udp. MIO_SVC_DNC_SEND_FLAG_ALL = (MIO_SVC_DNC_SEND_FLAG_PREFER_TCP | MIO_SVC_DNC_SEND_FLAG_TCP_IF_TC) }; typedef enum mio_svc_dnc_send_flag_t mio_svc_dnc_send_flag_t; enum mio_svc_dnc_resolve_flag_t { MIO_SVC_DNC_RESOLVE_FLAG_PREFER_TCP = MIO_SVC_DNC_SEND_FLAG_PREFER_TCP, MIO_SVC_DNC_RESOLVE_FLAG_TCP_IF_TC = MIO_SVC_DNC_SEND_FLAG_TCP_IF_TC, /* the following flag bits are resolver specific. it must not overlap with send flag bits */ MIO_SVC_DNC_RESOLVE_FLAG_BRIEF = (1 << 8), MIO_SVC_DNC_RESOLVE_FLAG_COOKIE = (1 << 9), MIO_SVC_DNC_RESOLVE_FLAG_ALL = (MIO_SVC_DNC_RESOLVE_FLAG_PREFER_TCP | MIO_SVC_DNC_RESOLVE_FLAG_TCP_IF_TC | MIO_SVC_DNC_RESOLVE_FLAG_BRIEF | MIO_SVC_DNC_RESOLVE_FLAG_COOKIE) }; typedef enum mio_svc_dnc_resolve_flag_t mio_svc_dnc_resolve_flag_t; /* ---------------------------------------------------------------- */ #define MIO_DNS_COOKIE_CLIENT_LEN (8) #define MIO_DNS_COOKIE_SERVER_MIN_LEN (16) #define MIO_DNS_COOKIE_SERVER_MAX_LEN (40) #define MIO_DNS_COOKIE_MAX_LEN (MIO_DNS_COOKIE_CLIENT_LEN + MIO_DNS_COOKIE_SERVER_MAX_LEN) typedef struct mio_dns_cookie_data_t mio_dns_cookie_data_t; #include struct mio_dns_cookie_data_t { mio_uint8_t client[MIO_DNS_COOKIE_CLIENT_LEN]; mio_uint8_t server[MIO_DNS_COOKIE_SERVER_MAX_LEN]; }; #include typedef struct mio_dns_cookie_t mio_dns_cookie_t; struct mio_dns_cookie_t { mio_dns_cookie_data_t data; mio_uint8_t client_len; mio_uint8_t server_len; }; /* ---------------------------------------------------------------- */ struct mio_dns_pkt_info_t { /* the following 5 fields are internal use only */ mio_uint8_t* _start; mio_uint8_t* _end; mio_uint8_t* _ptr; mio_oow_t _rrdlen; /* length needed to store RRs decoded */ mio_uint8_t* _rrdptr; /* you may access the following fields */ mio_dns_bhdr_t hdr; struct { int exist; mio_uint16_t uplen; /* udp payload len - will be placed in the qclass field of RR. */ mio_uint8_t version; mio_uint8_t dnssecok; mio_dns_cookie_t cookie; int cookie_verified; /* UGLY: set via mio_svc_dnc_resolve() only. mio_dns_make_packet_info() doesn't set this */ } edns; mio_uint16_t qdcount; /* number of questions */ mio_uint16_t ancount; /* number of answers (answer part) */ mio_uint16_t nscount; /* number of name servers (authority part. only NS types) */ mio_uint16_t arcount; /* number of additional resource (additional part) */ struct { mio_dns_bqr_t* qd; mio_dns_brr_t* an; mio_dns_brr_t* ns; mio_dns_brr_t* ar; } rr; }; typedef struct mio_dns_pkt_info_t mio_dns_pkt_info_t; /* ---------------------------------------------------------------- */ #if defined(__cplusplus) extern "C" { #endif MIO_EXPORT mio_svc_dnc_t* mio_svc_dnc_start ( mio_t* mio, const mio_skad_t* serv_addr, /* required */ const mio_skad_t* bind_addr, /* optional. can be MIO_NULL */ const mio_ntime_t* send_tmout, /* required */ const mio_ntime_t* reply_tmout, /* required */ mio_oow_t max_tries /* required */ ); MIO_EXPORT void mio_svc_dnc_stop ( mio_svc_dnc_t* dnc ); #if defined(MIO_HAVE_INLINE) static MIO_INLINE mio_t* mio_svc_dns_getmio(mio_svc_dns_t* svc) { return mio_svc_getmio((mio_svc_t*)svc); } static MIO_INLINE mio_t* mio_svc_dnc_getmio(mio_svc_dnc_t* svc) { return mio_svc_getmio((mio_svc_t*)svc); } static MIO_INLINE mio_t* mio_svc_dnr_getmio(mio_svc_dnr_t* svc) { return mio_svc_getmio((mio_svc_t*)svc); } #else # define mio_svc_dns_getmio(svc) mio_svc_getmio(svc) # define mio_svc_dnc_getmio(svc) mio_svc_getmio(svc) # define mio_svc_dnr_getmio(svc) mio_svc_getmio(svc) #endif MIO_EXPORT mio_dns_msg_t* mio_svc_dnc_sendmsg ( mio_svc_dnc_t* dnc, mio_dns_bhdr_t* bdns, mio_dns_bqr_t* qr, mio_oow_t qr_count, mio_dns_brr_t* rr, mio_oow_t rr_count, mio_dns_bedns_t* edns, int send_flags, mio_svc_dnc_on_done_t on_done, mio_oow_t xtnsize ); MIO_EXPORT mio_dns_msg_t* mio_svc_dnc_sendreq ( mio_svc_dnc_t* dnc, mio_dns_bhdr_t* bdns, mio_dns_bqr_t* qr, mio_dns_bedns_t* edns, int send_flags, mio_svc_dnc_on_done_t on_done, mio_oow_t xtnsize ); MIO_EXPORT mio_dns_msg_t* mio_svc_dnc_resolve ( mio_svc_dnc_t* dnc, const mio_bch_t* qname, mio_dns_rrt_t qtype, int resolve_flags, mio_svc_dnc_on_resolve_t on_resolve, mio_oow_t xtnsize ); /* ---------------------------------------------------------------- */ MIO_EXPORT mio_dns_pkt_info_t* mio_dns_make_packet_info ( mio_t* mio, const mio_dns_pkt_t* pkt, mio_oow_t len ); MIO_EXPORT void mio_dns_free_packet_info ( mio_t* mio, mio_dns_pkt_info_t* pi ); /* ---------------------------------------------------------------- */ #if defined(MIO_HAVE_INLINE) static MIO_INLINE mio_dns_pkt_t* mio_dns_msg_to_pkt (mio_dns_msg_t* msg) { return (mio_dns_pkt_t*)(msg + 1); } #else # define mio_dns_msg_to_pkt(msg) ((mio_dns_pkt_t*)((mio_dns_msg_t*)(msg) + 1)) #endif MIO_EXPORT mio_dns_msg_t* mio_dns_make_msg ( mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t* qr, mio_oow_t qr_count, mio_dns_brr_t* rr, mio_oow_t rr_count, mio_dns_bedns_t* edns, mio_oow_t xtnsize ); MIO_EXPORT void mio_dns_free_msg ( mio_t* mio, mio_dns_msg_t* msg ); #if defined(__cplusplus) } #endif #endif