/*
 * Copyright 2009-2020, Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 */

/*
 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*
 * Copyright (c) 1983, 1987, 1989
 *    The Regents of the University of California.  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.
 * 3. Neither the name of the University 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 REGENTS 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 REGENTS 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 _RESOLV_H_
#define _RESOLV_H_

#include <stdint.h>
#include <stdio.h>
#include <arpa/nameser.h>
#include <netinet/in.h>

#ifdef __cplusplus
extern "C" {
#endif

#define __RES   19991006

struct res_sym {
        int                     number;    /* Identifying number, like T_MX */
        const char *name;          /* Its symbolic name, like "MX" */
        const char *humanname; /* Its fun name, like "mail exchanger" */
};

/*
 * Global defines and variables for resolver stub.
 */
#define MAXNS                           3       /* max # name servers we'll track */
#define MAXDFLSRCH                      3       /* # default domain levels to try */
#define MAXDNSRCH                       6       /* max # domains in search path */
#define LOCALDOMAINPARTS        2       /* min levels in name that is "local" */
#define RES_TIMEOUT                     5       /* min. seconds between retries */
#define MAXRESOLVSORT           10      /* number of net to sort on */
#define RES_MAXNDOTS            15      /* should reflect bit field size */
#define RES_MAXRETRANS          30      /* only for resolv.conf/RES_OPTIONS */
#define RES_MAXRETRY            5       /* only for resolv.conf/RES_OPTIONS */
#define RES_DFLRETRY            2       /* Default #/tries. */
#define RES_MAXTIME                     65535   /* Infinity, in milliseconds. */

struct __res_state {
        int     retrans;                        /* retransmission time interval */
        int     retry;                          /* number of times to retransmit */
        unsigned long options;  /* option flags - see below. */
        int     nscount;                        /* number of name servers */
        struct sockaddr_in
                nsaddr_list[MAXNS];     /* address of name server */
        unsigned short  id;             /* current message id */
        char    *dnsrch[MAXDNSRCH+1];   /* components of domain to search */
        char    defdname[256];  /* default domain (deprecated) */
        unsigned long   pfcode; /* RES_PRF_ flags - see below. */
        unsigned ndots:4;               /* threshold for initial abs. query */
        unsigned nsort:4;               /* number of elements in sort_list[] */
        char    unused[3];
        struct {
                struct in_addr  addr;
                uint32_t        mask;
        } sort_list[MAXRESOLVSORT];
        void* qhook;    /* query hook */
        void* rhook;    /* response hook */
        int     res_h_errno;            /* last one set for this context */
        int     _vcsock;                        /* PRIVATE: for res_send VC i/o */
        unsigned int    _flags;                 /* PRIVATE: see below */
        unsigned char   _rnd[16];               /* PRIVATE: random state */
        unsigned int    _pad;                   /* make _u 64 bit aligned */
        union {
                /* On an 32-bit arch this means 512b total. */
                char    pad[56 - 4*sizeof (int) - 2*sizeof (void *)];
                struct {
                        uint16_t                nscount;
                        uint16_t                nstimes[MAXNS]; /* ms. */
                        int                     nssocks[MAXNS];
                        struct __res_state_ext *ext;    /* extention for IPv6 */
                } _ext;
        } _u;
};

typedef struct __res_state *res_state;

/* resolver flags; for _flags in __res_state. */
#define RES_F_VC                0x00000001      /* socket is TCP */
#define RES_F_CONN              0x00000002      /* socket is connected */
#define RES_F_EDNS0ERR  0x00000004      /* EDNS0 caused errors */

/* res_findzonecut2() options */
#define RES_EXHAUSTIVE  0x00000001      /* always do all queries */
#define RES_IPV4ONLY    0x00000002      /* IPv4 only */
#define RES_IPV6ONLY    0x00000004      /* IPv6 only */

/* resolver options */
#define RES_INIT                (1 << 0)        /* address initialized */
#define RES_DEBUG               (1 << 1)        /* print debug messages */
#define RES_AAONLY              (1 << 2)        /* authoritative answers only (!IMPL)*/
#define RES_USEVC               (1 << 3)        /* use virtual circuit */
#define RES_PRIMARY             (1 << 4)        /* query primary server only (!IMPL) */
#define RES_IGNTC               (1 << 5)        /* ignore trucation errors */
#define RES_RECURSE             (1 << 6)        /* recursion desired */
#define RES_DEFNAMES    (1 << 7)        /* use default domain name */
#define RES_STAYOPEN    (1 << 8)        /* Keep TCP socket open */
#define RES_DNSRCH              (1 << 9)        /* search up local domain tree */
#define RES_INSECURE1   (1 << 10)       /* type 1 security disabled */
#define RES_INSECURE2   (1 << 11)       /* type 2 security disabled */
#define RES_NOALIASES   (1 << 12)       /* shuts off HOSTALIASES feature */
#define RES_USE_INET6   (1 << 13)       /* use/map IPv6 in gethostbyname() */
#define RES_ROTATE              (1 << 14)       /* rotate ns list after each query */
#define RES_NOCHECKNAME (1 << 15)       /* do not check names for sanity. */
#define RES_KEEPTSIG    (1 << 16)       /* do not strip TSIG records */
#define RES_BLAST               (1 << 17)       /* blast all recursive servers */

#define RES_NOTLDQUERY  (1 << 20)       /* don't unqualified name as a tld */
#define RES_USE_DNSSEC  (1 << 21)       /* use DNSSEC using OK bit in OPT */

#define RES_USE_INET4   (1 << 23)       /* use IPv4 in gethostbyname() */

/* KAME extensions: use higher bit to avoid conflict with ISC use */
#define RES_USE_EDNS0   0x40000000      /* use EDNS0 if configured */
#define RES_NO_NIBBLE2  0x80000000      /* disable alternate nibble lookup */

#define RES_DEFAULT     \
        (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH | RES_NO_NIBBLE2)

/* resolver "pfcode" values, used by dig. */
#define RES_PRF_STATS   0x00000001
#define RES_PRF_UPDATE  0x00000002
#define RES_PRF_CLASS   0x00000004
#define RES_PRF_CMD             0x00000008
#define RES_PRF_QUES    0x00000010
#define RES_PRF_ANS             0x00000020
#define RES_PRF_AUTH    0x00000040
#define RES_PRF_ADD             0x00000080
#define RES_PRF_HEAD1   0x00000100
#define RES_PRF_HEAD2   0x00000200
#define RES_PRF_TTLID   0x00000400
#define RES_PRF_HEADX   0x00000800
#define RES_PRF_QUERY   0x00001000
#define RES_PRF_REPLY   0x00002000
#define RES_PRF_INIT    0x00004000

/* Things involving an internal (static) resolver context. */
extern struct __res_state *__res_state(void) __attribute__ ((__const__));
#define _res (*__res_state())

#define fp_nquery               __fp_nquery
#define fp_query                __fp_query
#define hostalias               __hostalias
#define p_query                 __p_query
#define res_close               __res_close
#define res_init                __res_init
#define res_isourserver __res_isourserver
#define res_mkquery             __res_mkquery
#define res_query               __res_query
#define res_querydomain __res_querydomain
#define res_search              __res_search
#define res_send                __res_send

void            fp_nquery(const unsigned char *, int, FILE *);
void            fp_query(const unsigned char *, FILE *);
const char *hostalias(const char *);
void            p_query(const unsigned char *);
void            res_close(void);
int                     res_init(void);
int                     res_isourserver(const struct sockaddr_in *);
int                     res_mkquery(int, const char *, int, int, const unsigned char *,
                                 int, const unsigned char *, unsigned char *, int);
int                     res_query(const char *, int, int, unsigned char *, int);
int                     res_querydomain(const char *, const char *, int, int,
                                unsigned char *, int);
int                     res_search(const char *, int, int, unsigned char *, int);
int                     res_send(const unsigned char *, int, unsigned char *, int);

#define b64_ntop                        __b64_ntop
#define b64_pton                        __b64_pton
#define dn_comp                         __dn_comp
#define dn_count_labels         __dn_count_labels
#define dn_expand                       __dn_expand
#define dn_skipname                     __dn_skipname
#define fp_resstat                      __fp_resstat
#define loc_aton                        __loc_aton
#define loc_ntoa                        __loc_ntoa
#define p_cdname                        __p_cdname
#define p_cdnname                       __p_cdnname
#define p_class                         __p_class
#define p_fqname                        __p_fqname
#define p_fqnname                       __p_fqnname
#define p_option                        __p_option
#define p_time                          __p_time
#define p_type                          __p_type
#define p_rcode                         __p_rcode
#define res_dnok                        __res_dnok
#define res_hnok                        __res_hnok
#define res_hostalias           __res_hostalias
#define res_mailok                      __res_mailok
#define res_nameinquery         __res_nameinquery
#define res_nclose                      __res_nclose
#define res_ninit                       __res_ninit
#define res_nmkquery            __res_nmkquery
#define res_nquery                      __res_nquery
#define res_nquerydomain        __res_nquerydomain
#define res_nsearch                     __res_nsearch
#define res_nsend                       __res_nsend
#define res_ownok                       __res_ownok
#define res_queriesmatch        __res_queriesmatch
#define res_randomid            __res_randomid
#define sym_ntop                        __sym_ntop
#define sym_ntos                        __sym_ntos
#define sym_ston                        __sym_ston

int                             res_hnok(const char *);
int                             res_ownok(const char *);
int                             res_mailok(const char *);
int                             res_dnok(const char *);
int                             sym_ston(const struct res_sym *, const char *, int *);
const char *    sym_ntos(const struct res_sym *, int, int *);
const char *    sym_ntop(const struct res_sym *, int, int *);
int                             b64_ntop(unsigned char const *, size_t, char *, size_t);
int                             b64_pton(char const *, unsigned char *, size_t);
int                             loc_aton(const char *, unsigned char *);
const char *    loc_ntoa(const unsigned char *, char *);
int                             dn_skipname(const unsigned char *, const unsigned char *);
const char *    p_class(int);
const char *    p_time(uint32_t);
const char *    p_type(int);
const char *    p_rcode(int);
const unsigned char * p_cdnname(const unsigned char *, const unsigned char *,
                                                int, FILE *);
const unsigned char * p_cdname(const unsigned char *, const unsigned char *,
                                                FILE *);
const unsigned char * p_fqnname(const unsigned char *, const unsigned char *,
                                                int, char *, int);
const unsigned char * p_fqname(const unsigned char *, const unsigned char *,
                                                FILE *);
const char *    p_option(unsigned long);
int                             dn_count_labels(const char *);
int                             dn_comp(const char *, unsigned char *, int, unsigned char **,
                                        unsigned char **);
int                             dn_expand(const unsigned char *, const unsigned char *,
                                        const unsigned char *, char *, int);
unsigned int    res_randomid(void);
int                             res_nameinquery(const char *, int, int, const unsigned char *,
                                        const unsigned char *);
int                             res_queriesmatch(const unsigned char *, const unsigned char *,
                                        const unsigned char *, const unsigned char *);

/* Things involving a resolver context. */
int                             res_ninit(res_state);
void                    fp_resstat(const res_state, FILE *);
const char *    res_hostalias(const res_state, const char *, char *, size_t);
int                             res_nquery(res_state, const char *, int, int, unsigned char *,
                                        int);
int                             res_nsearch(res_state, const char *, int, int, unsigned char *,
                                        int);
int                             res_nquerydomain(res_state, const char *, const char *, int,
                                        int, unsigned char *, int);
int                             res_nmkquery(res_state, int, const char *, int, int,
                                        const unsigned char *, int, const unsigned char *,
                                        unsigned char *, int);
int                             res_nsend(res_state, const unsigned char *, int, unsigned char *,
                                        int);
void                    res_nclose(res_state);

#ifdef __cplusplus
}
#endif

#endif /* !_RESOLV_H_ */