ircd-hybrid-7.2/src/irc_getaddrinfo.c

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * 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 project 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 PROJECT 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 PROJECT 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.
 */

#include "stdinc.h"

#include <stdarg.h>
#include "irc_getaddrinfo.h"
#include "ircd_defs.h"

/*  $Id$ */

static const char in_addrany[]  = { 0, 0, 0, 0 };
static const char in_loopback[] = { 127, 0, 0, 1 };
static const char in6_addrany[] = {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
static const char in6_loopback[] = {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
};

static const struct afd {
        int a_af;
        int a_addrlen;
        int a_socklen;
        int a_off;
        const char *a_addrany;
        const char *a_loopback;
        int a_scoped;
} afdl [] = {
#define N_INET6 0
#ifdef IPV6
        {PF_INET6, sizeof(struct in6_addr),
         sizeof(struct sockaddr_in6),
         offsetof(struct sockaddr_in6, sin6_addr),
         in6_addrany, in6_loopback, 1},
#endif
#define N_INET 1
        {PF_INET, sizeof(struct in_addr),
         sizeof(struct sockaddr_in),
         offsetof(struct sockaddr_in, sin_addr),
         in_addrany, in_loopback, 0},
        {0, 0, 0, 0, NULL, NULL, 0},
};

struct explore {
        int e_af;
        int e_socktype;
        int e_protocol;
        const char *e_protostr;
        int e_wild;
#define WILD_AF(ex)             ((ex)->e_wild & 0x01)
#define WILD_SOCKTYPE(ex)       ((ex)->e_wild & 0x02)
#define WILD_PROTOCOL(ex)       ((ex)->e_wild & 0x04)
};

static const struct explore explore[] = {
#ifdef IPV6
        { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
        { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
        { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
#endif
        { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
        { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
        { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
        { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
        { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
        { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
        { -1, 0, 0, NULL, 0 },
};

#define PTON_MAX        16

static int str_isnumber(const char *);
static int explore_null(const struct addrinfo *,
        const char *, struct addrinfo **);
static int explore_numeric(const struct addrinfo *, const char *,
        const char *, struct addrinfo **);
static struct addrinfo *get_ai(const struct addrinfo *,
        const struct afd *, const char *);
static int get_portmatch(const struct addrinfo *, const char *);
static int get_port(struct addrinfo *, const char *, int);
static const struct afd *find_afd(int);
#if 0
/* We will need this should we ever want gai_strerror() */
static char *ai_errlist[] = {
        "Success",
        "Address family for hostname not supported",    /* EAI_ADDRFAMILY */
        "Temporary failure in name resolution",         /* EAI_AGAIN      */
        "Invalid value for ai_flags",                   /* EAI_BADFLAGS   */
        "Non-recoverable failure in name resolution",   /* EAI_FAIL       */
        "ai_family not supported",                      /* EAI_FAMILY     */
        "Memory allocation failure",                    /* EAI_MEMORY     */
        "No address associated with hostname",          /* EAI_NODATA     */
        "hostname nor servname provided, or not known", /* EAI_NONAME     */
        "servname not supported for ai_socktype",       /* EAI_SERVICE    */
        "ai_socktype not supported",                    /* EAI_SOCKTYPE   */
        "System error returned in errno",               /* EAI_SYSTEM     */
        "Invalid value for hints",                      /* EAI_BADHINTS   */
        "Resolved protocol is unknown",                 /* EAI_PROTOCOL   */
        "Unknown error",                                /* EAI_MAX        */
};
#endif
/* XXX macros that make external reference is BAD. */

#define GET_AI(ai, afd, addr) \
do { \
        /* external reference: pai, error, and label free */ \
        (ai) = get_ai(pai, (afd), (addr)); \
        if ((ai) == NULL) { \
                error = EAI_MEMORY; \
                goto free; \
        } \
} while (/*CONSTCOND*/0)

#define GET_PORT(ai, serv) \
do { \
        /* external reference: error and label free */ \
        error = get_port((ai), (serv), 0); \
        if (error != 0) \
                goto free; \
} while (/*CONSTCOND*/0)

#define ERR(err) \
do { \
        /* external reference: error, and label bad */ \
        error = (err); \
        goto bad; \
        /*NOTREACHED*/ \
} while (/*CONSTCOND*/0)

#define MATCH_FAMILY(x, y, w) \
        ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
#define MATCH(x, y, w) \
        ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))

#if 0
/* We will need this should we ever want gai_strerror() */
char *
irc_gai_strerror(int ecode)
{
        if (ecode < 0 || ecode > EAI_MAX)
                ecode = EAI_MAX;
        return ai_errlist[ecode];
}
#endif

void
irc_freeaddrinfo(struct addrinfo *ai)
{
        struct addrinfo *next;

        do {
                next = ai->ai_next;
                if (ai->ai_canonname)
                        free(ai->ai_canonname);
                /* no need to free(ai->ai_addr) */
                free(ai);
                ai = next;
        } while (ai);
}

static int
str_isnumber(const char *p)
{
        char *ep;

        if (*p == '\0')
                return NO;
        ep = NULL;
        errno = 0;
        (void)strtoul(p, &ep, 10);
        if (errno == 0 && ep && *ep == '\0')
                return YES;
        else
                return NO;
}

int
irc_getaddrinfo(const char *hostname, const char *servname,
                const struct addrinfo *hints, struct addrinfo **res)
{
  struct addrinfo sentinel;
  struct addrinfo *cur;
  int error = 0;
  struct addrinfo ai;
  struct addrinfo ai0;
  struct addrinfo *pai;
  const struct explore *ex;

  memset(&sentinel, 0, sizeof(sentinel));
  cur = &sentinel;
  pai = &ai;
  pai->ai_flags = 0;
  pai->ai_family = PF_UNSPEC;
  pai->ai_socktype = ANY;
  pai->ai_protocol = ANY;
  pai->ai_addrlen = 0;
  pai->ai_canonname = NULL;
  pai->ai_addr = NULL;
  pai->ai_next = NULL;

  if (hostname == NULL && servname == NULL)
    return EAI_NONAME;
        if (hints) {
                /* error check for hints */
                if (hints->ai_addrlen || hints->ai_canonname ||
                    hints->ai_addr || hints->ai_next)
                        ERR(EAI_BADHINTS); /* xxx */
                if (hints->ai_flags & ~AI_MASK)
                        ERR(EAI_BADFLAGS);
                switch (hints->ai_family) {
                case PF_UNSPEC:
                case PF_INET:
#ifdef IPV6
                case PF_INET6:
#endif
                        break;
                default:
                        ERR(EAI_FAMILY);
                }
                memcpy(pai, hints, sizeof(*pai));

                /*
                 * if both socktype/protocol are specified, check if they
                 * are meaningful combination.
                 */
                if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
                        for (ex = explore; ex->e_af >= 0; ex++) {
                                if (pai->ai_family != ex->e_af)
                                        continue;
                                if (ex->e_socktype == ANY)
                                        continue;
                                if (ex->e_protocol == ANY)
                                        continue;
                                if (pai->ai_socktype == ex->e_socktype &&
                                    pai->ai_protocol != ex->e_protocol) {
                                        ERR(EAI_BADHINTS);
                                }
                        }
                }
        }

        /*
         * check for special cases.  (1) numeric servname is disallowed if
         * socktype/protocol are left unspecified. (2) servname is disallowed
         * for raw and other inet{,6} sockets.
         */
        if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
#ifdef IPV6
            || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
#endif
            ) {
                ai0 = *pai;     /* backup *pai */

                if (pai->ai_family == PF_UNSPEC) {
#ifdef IPV6
                        pai->ai_family = PF_INET6;
#else
                        pai->ai_family = PF_INET;
#endif
                }
                error = get_portmatch(pai, servname);
                if (error)
                        ERR(error);

                *pai = ai0;
        }

        ai0 = *pai;

        /* NULL hostname, or numeric hostname */
        for (ex = explore; ex->e_af >= 0; ex++) {
                *pai = ai0;

                /* PF_UNSPEC entries are prepared for DNS queries only */
                if (ex->e_af == PF_UNSPEC)
                        continue;

                if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
                        continue;
                if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
                        continue;
                if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
                        continue;

                if (pai->ai_family == PF_UNSPEC)
                        pai->ai_family = ex->e_af;
                if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
                        pai->ai_socktype = ex->e_socktype;
                if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
                        pai->ai_protocol = ex->e_protocol;

                if (hostname == NULL)
                        error = explore_null(pai, servname, &cur->ai_next);
                else
                        error = explore_numeric(pai, hostname, servname, &cur->ai_next);

                if (error)
                        goto free;

                while (cur && cur->ai_next)
                        cur = cur->ai_next;
        }

        /*
         * XXX
         * If numreic representation of AF1 can be interpreted as FQDN
         * representation of AF2, we need to think again about the code below.
         */
        if (sentinel.ai_next)
                goto good;

        if (pai->ai_flags & AI_NUMERICHOST)
                ERR(EAI_NONAME);
        if (hostname == NULL)
                ERR(EAI_NODATA);

        /* XXX */
        if (sentinel.ai_next)
                error = 0;

        if (error)
                goto free;
        if (error == 0) {
                if (sentinel.ai_next) {
 good:
                        *res = sentinel.ai_next;
                        return SUCCESS;
                } else
                        error = EAI_FAIL;
        }
 free:
 bad:
        if (sentinel.ai_next)
                irc_freeaddrinfo(sentinel.ai_next);
        *res = NULL;
        return error;
}

/*
 * hostname == NULL.
 * passive socket -> anyaddr (0.0.0.0 or ::)
 * non-passive socket -> localhost (127.0.0.1 or ::1)
 */
static int
explore_null(const struct addrinfo *pai, const char *servname, struct addrinfo **res)
{
  int s;
  const struct afd *afd;
  struct addrinfo *cur;
  struct addrinfo sentinel;
  int error;

        *res = NULL;
        sentinel.ai_next = NULL;
        cur = &sentinel;

        /*
         * filter out AFs that are not supported by the kernel
         * XXX errno?
         */
        s = socket(pai->ai_family, SOCK_DGRAM, 0);
        if (s < 0) {
#ifdef _WIN32
                errno = WSAGetLastError();
#endif
                if (errno != EMFILE)
                        return 0;
        } else
#ifdef _WIN32
                closesocket(s);
#else
                close(s);
#endif

        /*
         * if the servname does not match socktype/protocol, ignore it.
         */
        if (get_portmatch(pai, servname) != 0)
                return 0;

        afd = find_afd(pai->ai_family);
        if (afd == NULL)
                return 0;

        if (pai->ai_flags & AI_PASSIVE) {
                GET_AI(cur->ai_next, afd, afd->a_addrany);
                GET_PORT(cur->ai_next, servname);
        } else {
                GET_AI(cur->ai_next, afd, afd->a_loopback);
                GET_PORT(cur->ai_next, servname);
        }
        cur = cur->ai_next;

        *res = sentinel.ai_next;
        return 0;

free:
        if (sentinel.ai_next)
                irc_freeaddrinfo(sentinel.ai_next);
        return error;
}

/*
 * numeric hostname
 */
static int
explore_numeric(const struct addrinfo *pai, const char *hostname,
                const char *servname, struct addrinfo **res)
{
  const struct afd *afd;
  struct addrinfo *cur;
  struct addrinfo sentinel;
  int error;
  char pton[PTON_MAX];

  *res = NULL;
  sentinel.ai_next = NULL;
  cur = &sentinel;

        /*
         * if the servname does not match socktype/protocol, ignore it.
         */
        if (get_portmatch(pai, servname) != 0)
                return 0;

        afd = find_afd(pai->ai_family);
        if (afd == NULL)
                return 0;

        switch (afd->a_af) {
#if 1 /*X/Open spec*/
        case AF_INET:
                if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
                        if (pai->ai_family == afd->a_af ||
                            pai->ai_family == PF_UNSPEC /*?*/) {
                                GET_AI(cur->ai_next, afd, pton);
                                GET_PORT(cur->ai_next, servname);
                                while (cur && cur->ai_next)
                                        cur = cur->ai_next;
                        } else
                                ERR(EAI_FAMILY);        /*xxx*/
                }
                break;
#endif
        default:
                if (inet_pton(afd->a_af, hostname, pton) == 1) {
                        if (pai->ai_family == afd->a_af ||
                            pai->ai_family == PF_UNSPEC /*?*/) {
                                GET_AI(cur->ai_next, afd, pton);
                                GET_PORT(cur->ai_next, servname);
                                while (cur && cur->ai_next)
                                        cur = cur->ai_next;
                        } else
                                ERR(EAI_FAMILY);        /* XXX */
                }
                break;
        }

        *res = sentinel.ai_next;
        return 0;

free:
bad:
        if (sentinel.ai_next)
                irc_freeaddrinfo(sentinel.ai_next);
        return error;
}

static struct addrinfo *
get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
{
  char *p;
  struct addrinfo *ai;
        
    ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
                + (afd->a_socklen));
        if (ai == NULL)
                return NULL;

        memcpy(ai, pai, sizeof(struct addrinfo));
        ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
        memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
        ai->ai_addrlen = afd->a_socklen;
        ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
        p = (char *)(void *)(ai->ai_addr);
        memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
        return ai;
}

static int
get_portmatch(const struct addrinfo *ai, const char *servname)
{
  /* get_port does not touch first argument. when matchonly == 1. */
  /* LINTED const cast */
  return(get_port((struct addrinfo *)ai, servname, 1));
}

static int
get_port(struct addrinfo *ai, const char *servname, int matchonly)
{
  const char *proto;
  struct servent *sp;
  int port;
  int allownumeric;

  if (servname == NULL)
    return 0;
        switch (ai->ai_family) {
        case AF_INET:
#ifdef AF_INET6
        case AF_INET6:
#endif
                break;
        default:
                return 0;
        }

        switch (ai->ai_socktype) {
        case SOCK_RAW:
                return EAI_SERVICE;
        case SOCK_DGRAM:
        case SOCK_STREAM:
                allownumeric = 1;
                break;
        case ANY:
                allownumeric = 0;
                break;
        default:
                return EAI_SOCKTYPE;
        }

        if (str_isnumber(servname)) {
                if (!allownumeric)
                        return EAI_SERVICE;
                port = atoi(servname);
                if (port < 0 || port > 65535)
                        return EAI_SERVICE;
                port = htons(port);
        } else {
                switch (ai->ai_socktype) {
                case SOCK_DGRAM:
                        proto = "udp";
                        break;
                case SOCK_STREAM:
                        proto = "tcp";
                        break;
                default:
                        proto = NULL;
                        break;
                }

                if ((sp = getservbyname(servname, proto)) == NULL)
                        return EAI_SERVICE;
                port = sp->s_port;
        }

        if (!matchonly) {
                switch (ai->ai_family) {
                case AF_INET:
                        ((struct sockaddr_in *)(void *)
                            ai->ai_addr)->sin_port = port;
                        break;
#ifdef IPV6
                case AF_INET6:
                        ((struct sockaddr_in6 *)(void *)
                            ai->ai_addr)->sin6_port = port;
                        break;
#endif
                }
        }

        return 0;
}

static const struct afd *
find_afd(int af)
{
  const struct afd *afd;

  if (af == PF_UNSPEC)
    return(NULL);

  for (afd = afdl; afd->a_af; afd++)
  {
    if (afd->a_af == af)
      return(afd);
  }

  return(NULL);
}
Revision:	33
Committed:	Sun Oct 2 20:50:00 2005 UTC (19 years, 10 months ago) by knight
Content type:	text/x-csrc
Original Path:	*ircd-hybrid/src/irc_getaddrinfo.c*
File size:	14738 byte(s)
Log Message:	- svn:keywords
#	User	Rev	Content
1	adx	30	/*
2			* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3			* All rights reserved.
4			*
5			* Redistribution and use in source and binary forms, with or without
6			* modification, are permitted provided that the following conditions
7			* are met:
8			* 1. Redistributions of source code must retain the above copyright
9			* notice, this list of conditions and the following disclaimer.
10			* 2. Redistributions in binary form must reproduce the above copyright
11			* notice, this list of conditions and the following disclaimer in the
12			* documentation and/or other materials provided with the distribution.
13			* 3. Neither the name of the project nor the names of its contributors
14			* may be used to endorse or promote products derived from this software
15			* without specific prior written permission.
16			*
17			* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20			* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27			* SUCH DAMAGE.
28			*/
29
30			#include "stdinc.h"
31
32			#include <stdarg.h>
33			#include "irc_getaddrinfo.h"
34			#include "ircd_defs.h"
35
36	knight	31	/* $Id$ */
37	adx	30
38			static const char in_addrany[] = { 0, 0, 0, 0 };
39			static const char in_loopback[] = { 127, 0, 0, 1 };
40			static const char in6_addrany[] = {
41			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
42			};
43			static const char in6_loopback[] = {
44			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
45			};
46
47			static const struct afd {
48			int a_af;
49			int a_addrlen;
50			int a_socklen;
51			int a_off;
52			const char *a_addrany;
53			const char *a_loopback;
54			int a_scoped;
55			} afdl [] = {
56			#define N_INET6 0
57			#ifdef IPV6
58			{PF_INET6, sizeof(struct in6_addr),
59			sizeof(struct sockaddr_in6),
60			offsetof(struct sockaddr_in6, sin6_addr),
61			in6_addrany, in6_loopback, 1},
62			#endif
63			#define N_INET 1
64			{PF_INET, sizeof(struct in_addr),
65			sizeof(struct sockaddr_in),
66			offsetof(struct sockaddr_in, sin_addr),
67			in_addrany, in_loopback, 0},
68			{0, 0, 0, 0, NULL, NULL, 0},
69			};
70
71			struct explore {
72			int e_af;
73			int e_socktype;
74			int e_protocol;
75			const char *e_protostr;
76			int e_wild;
77			#define WILD_AF(ex) ((ex)->e_wild & 0x01)
78			#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
79			#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
80			};
81
82			static const struct explore explore[] = {
83			#ifdef IPV6
84			{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
85			{ PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
86			{ PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
87			#endif
88			{ PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
89			{ PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
90			{ PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
91			{ PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
92			{ PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
93			{ PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
94			{ -1, 0, 0, NULL, 0 },
95			};
96
97			#define PTON_MAX 16
98
99			static int str_isnumber(const char *);
100			static int explore_null(const struct addrinfo *,
101			const char , struct addrinfo *);
102			static int explore_numeric(const struct addrinfo , const char ,
103			const char , struct addrinfo *);
104			static struct addrinfo get_ai(const struct addrinfo ,
105			const struct afd , const char );
106			static int get_portmatch(const struct addrinfo , const char );
107			static int get_port(struct addrinfo , const char , int);
108			static const struct afd *find_afd(int);
109			#if 0
110			/* We will need this should we ever want gai_strerror() */
111			static char *ai_errlist[] = {
112			"Success",
113			"Address family for hostname not supported", /* EAI_ADDRFAMILY */
114			"Temporary failure in name resolution", /* EAI_AGAIN */
115			"Invalid value for ai_flags", /* EAI_BADFLAGS */
116			"Non-recoverable failure in name resolution", /* EAI_FAIL */
117			"ai_family not supported", /* EAI_FAMILY */
118			"Memory allocation failure", /* EAI_MEMORY */
119			"No address associated with hostname", /* EAI_NODATA */
120			"hostname nor servname provided, or not known", /* EAI_NONAME */
121			"servname not supported for ai_socktype", /* EAI_SERVICE */
122			"ai_socktype not supported", /* EAI_SOCKTYPE */
123			"System error returned in errno", /* EAI_SYSTEM */
124			"Invalid value for hints", /* EAI_BADHINTS */
125			"Resolved protocol is unknown", /* EAI_PROTOCOL */
126			"Unknown error", /* EAI_MAX */
127			};
128			#endif
129			/* XXX macros that make external reference is BAD. */
130
131			#define GET_AI(ai, afd, addr) \
132			do { \
133			/* external reference: pai, error, and label free */ \
134			(ai) = get_ai(pai, (afd), (addr)); \
135			if ((ai) == NULL) { \
136			error = EAI_MEMORY; \
137			goto free; \
138			} \
139			} while (/CONSTCOND/0)
140
141			#define GET_PORT(ai, serv) \
142			do { \
143			/* external reference: error and label free */ \
144			error = get_port((ai), (serv), 0); \
145			if (error != 0) \
146			goto free; \
147			} while (/CONSTCOND/0)
148
149			#define ERR(err) \
150			do { \
151			/* external reference: error, and label bad */ \
152			error = (err); \
153			goto bad; \
154			/NOTREACHED/ \
155			} while (/CONSTCOND/0)
156
157			#define MATCH_FAMILY(x, y, w) \
158			((x) == (y) \|\| (/CONSTCOND/(w) && ((x) == PF_UNSPEC \|\| (y) == PF_UNSPEC)))
159			#define MATCH(x, y, w) \
160			((x) == (y) \|\| (/CONSTCOND/(w) && ((x) == ANY \|\| (y) == ANY)))
161
162			#if 0
163			/* We will need this should we ever want gai_strerror() */
164			char *
165			irc_gai_strerror(int ecode)
166			{
167			if (ecode < 0 \|\| ecode > EAI_MAX)
168			ecode = EAI_MAX;
169			return ai_errlist[ecode];
170			}
171			#endif
172
173			void
174			irc_freeaddrinfo(struct addrinfo *ai)
175			{
176			struct addrinfo *next;
177
178			do {
179			next = ai->ai_next;
180			if (ai->ai_canonname)
181			free(ai->ai_canonname);
182			/* no need to free(ai->ai_addr) */
183			free(ai);
184			ai = next;
185			} while (ai);
186			}
187
188			static int
189			str_isnumber(const char *p)
190			{
191			char *ep;
192
193			if (*p == '\0')
194			return NO;
195			ep = NULL;
196			errno = 0;
197			(void)strtoul(p, &ep, 10);
198			if (errno == 0 && ep && *ep == '\0')
199			return YES;
200			else
201			return NO;
202			}
203
204			int
205			irc_getaddrinfo(const char hostname, const char servname,
206			const struct addrinfo hints, struct addrinfo *res)
207			{
208			struct addrinfo sentinel;
209			struct addrinfo *cur;
210			int error = 0;
211			struct addrinfo ai;
212			struct addrinfo ai0;
213			struct addrinfo *pai;
214			const struct explore *ex;
215
216			memset(&sentinel, 0, sizeof(sentinel));
217			cur = &sentinel;
218			pai = &ai;
219			pai->ai_flags = 0;
220			pai->ai_family = PF_UNSPEC;
221			pai->ai_socktype = ANY;
222			pai->ai_protocol = ANY;
223			pai->ai_addrlen = 0;
224			pai->ai_canonname = NULL;
225			pai->ai_addr = NULL;
226			pai->ai_next = NULL;
227
228			if (hostname == NULL && servname == NULL)
229			return EAI_NONAME;
230			if (hints) {
231			/* error check for hints */
232			if (hints->ai_addrlen \|\| hints->ai_canonname \|\|
233			hints->ai_addr \|\| hints->ai_next)
234			ERR(EAI_BADHINTS); /* xxx */
235			if (hints->ai_flags & ~AI_MASK)
236			ERR(EAI_BADFLAGS);
237			switch (hints->ai_family) {
238			case PF_UNSPEC:
239			case PF_INET:
240			#ifdef IPV6
241			case PF_INET6:
242			#endif
243			break;
244			default:
245			ERR(EAI_FAMILY);
246			}
247			memcpy(pai, hints, sizeof(*pai));
248
249			/*
250			* if both socktype/protocol are specified, check if they
251			* are meaningful combination.
252			*/
253			if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
254			for (ex = explore; ex->e_af >= 0; ex++) {
255			if (pai->ai_family != ex->e_af)
256			continue;
257			if (ex->e_socktype == ANY)
258			continue;
259			if (ex->e_protocol == ANY)
260			continue;
261			if (pai->ai_socktype == ex->e_socktype &&
262			pai->ai_protocol != ex->e_protocol) {
263			ERR(EAI_BADHINTS);
264			}
265			}
266			}
267			}
268
269			/*
270			* check for special cases. (1) numeric servname is disallowed if
271			* socktype/protocol are left unspecified. (2) servname is disallowed
272			* for raw and other inet{,6} sockets.
273			*/
274			if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
275			#ifdef IPV6
276			\|\| MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
277			#endif
278			) {
279			ai0 = pai; / backup pai /
280
281			if (pai->ai_family == PF_UNSPEC) {
282			#ifdef IPV6
283			pai->ai_family = PF_INET6;
284			#else
285			pai->ai_family = PF_INET;
286			#endif
287			}
288			error = get_portmatch(pai, servname);
289			if (error)
290			ERR(error);
291
292			*pai = ai0;
293			}
294
295			ai0 = *pai;
296
297			/* NULL hostname, or numeric hostname */
298			for (ex = explore; ex->e_af >= 0; ex++) {
299			*pai = ai0;
300
301			/* PF_UNSPEC entries are prepared for DNS queries only */
302			if (ex->e_af == PF_UNSPEC)
303			continue;
304
305			if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
306			continue;
307			if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
308			continue;
309			if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
310			continue;
311
312			if (pai->ai_family == PF_UNSPEC)
313			pai->ai_family = ex->e_af;
314			if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
315			pai->ai_socktype = ex->e_socktype;
316			if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
317			pai->ai_protocol = ex->e_protocol;
318
319			if (hostname == NULL)
320			error = explore_null(pai, servname, &cur->ai_next);
321			else
322			error = explore_numeric(pai, hostname, servname, &cur->ai_next);
323
324			if (error)
325			goto free;
326
327			while (cur && cur->ai_next)
328			cur = cur->ai_next;
329			}
330
331			/*
332			* XXX
333			* If numreic representation of AF1 can be interpreted as FQDN
334			* representation of AF2, we need to think again about the code below.
335			*/
336			if (sentinel.ai_next)
337			goto good;
338
339			if (pai->ai_flags & AI_NUMERICHOST)
340			ERR(EAI_NONAME);
341			if (hostname == NULL)
342			ERR(EAI_NODATA);
343
344			/* XXX */
345			if (sentinel.ai_next)
346			error = 0;
347
348			if (error)
349			goto free;
350			if (error == 0) {
351			if (sentinel.ai_next) {
352			good:
353			*res = sentinel.ai_next;
354			return SUCCESS;
355			} else
356			error = EAI_FAIL;
357			}
358			free:
359			bad:
360			if (sentinel.ai_next)
361			irc_freeaddrinfo(sentinel.ai_next);
362			*res = NULL;
363			return error;
364			}
365
366			/*
367			* hostname == NULL.
368			* passive socket -> anyaddr (0.0.0.0 or ::)
369			* non-passive socket -> localhost (127.0.0.1 or ::1)
370			*/
371			static int
372			explore_null(const struct addrinfo pai, const char servname, struct addrinfo **res)
373			{
374			int s;
375			const struct afd *afd;
376			struct addrinfo *cur;
377			struct addrinfo sentinel;
378			int error;
379
380			*res = NULL;
381			sentinel.ai_next = NULL;
382			cur = &sentinel;
383
384			/*
385			* filter out AFs that are not supported by the kernel
386			* XXX errno?
387			*/
388			s = socket(pai->ai_family, SOCK_DGRAM, 0);
389			if (s < 0) {
390			#ifdef _WIN32
391			errno = WSAGetLastError();
392			#endif
393			if (errno != EMFILE)
394			return 0;
395			} else
396			#ifdef _WIN32
397			closesocket(s);
398			#else
399			close(s);
400			#endif
401
402			/*
403			* if the servname does not match socktype/protocol, ignore it.
404			*/
405			if (get_portmatch(pai, servname) != 0)
406			return 0;
407
408			afd = find_afd(pai->ai_family);
409			if (afd == NULL)
410			return 0;
411
412			if (pai->ai_flags & AI_PASSIVE) {
413			GET_AI(cur->ai_next, afd, afd->a_addrany);
414			GET_PORT(cur->ai_next, servname);
415			} else {
416			GET_AI(cur->ai_next, afd, afd->a_loopback);
417			GET_PORT(cur->ai_next, servname);
418			}
419			cur = cur->ai_next;
420
421			*res = sentinel.ai_next;
422			return 0;
423
424			free:
425			if (sentinel.ai_next)
426			irc_freeaddrinfo(sentinel.ai_next);
427			return error;
428			}
429
430			/*
431			* numeric hostname
432			*/
433			static int
434			explore_numeric(const struct addrinfo pai, const char hostname,
435			const char servname, struct addrinfo *res)
436			{
437			const struct afd *afd;
438			struct addrinfo *cur;
439			struct addrinfo sentinel;
440			int error;
441			char pton[PTON_MAX];
442
443			*res = NULL;
444			sentinel.ai_next = NULL;
445			cur = &sentinel;
446
447			/*
448			* if the servname does not match socktype/protocol, ignore it.
449			*/
450			if (get_portmatch(pai, servname) != 0)
451			return 0;
452
453			afd = find_afd(pai->ai_family);
454			if (afd == NULL)
455			return 0;
456
457			switch (afd->a_af) {
458			#if 1 /X/Open spec/
459			case AF_INET:
460			if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
461			if (pai->ai_family == afd->a_af \|\|
462			pai->ai_family == PF_UNSPEC /?/) {
463			GET_AI(cur->ai_next, afd, pton);
464			GET_PORT(cur->ai_next, servname);
465			while (cur && cur->ai_next)
466			cur = cur->ai_next;
467			} else
468			ERR(EAI_FAMILY); /xxx/
469			}
470			break;
471			#endif
472			default:
473			if (inet_pton(afd->a_af, hostname, pton) == 1) {
474			if (pai->ai_family == afd->a_af \|\|
475			pai->ai_family == PF_UNSPEC /?/) {
476			GET_AI(cur->ai_next, afd, pton);
477			GET_PORT(cur->ai_next, servname);
478			while (cur && cur->ai_next)
479			cur = cur->ai_next;
480			} else
481			ERR(EAI_FAMILY); /* XXX */
482			}
483			break;
484			}
485
486			*res = sentinel.ai_next;
487			return 0;
488
489			free:
490			bad:
491			if (sentinel.ai_next)
492			irc_freeaddrinfo(sentinel.ai_next);
493			return error;
494			}
495
496			static struct addrinfo *
497			get_ai(const struct addrinfo pai, const struct afd afd, const char *addr)
498			{
499			char *p;
500			struct addrinfo *ai;
501
502			ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
503			+ (afd->a_socklen));
504			if (ai == NULL)
505			return NULL;
506
507			memcpy(ai, pai, sizeof(struct addrinfo));
508			ai->ai_addr = (struct sockaddr )(void )(ai + 1);
509			memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
510			ai->ai_addrlen = afd->a_socklen;
511			ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
512			p = (char )(void )(ai->ai_addr);
513			memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
514			return ai;
515			}
516
517			static int
518			get_portmatch(const struct addrinfo ai, const char servname)
519			{
520			/* get_port does not touch first argument. when matchonly == 1. */
521			/* LINTED const cast */
522			return(get_port((struct addrinfo *)ai, servname, 1));
523			}
524
525			static int
526			get_port(struct addrinfo ai, const char servname, int matchonly)
527			{
528			const char *proto;
529			struct servent *sp;
530			int port;
531			int allownumeric;
532
533			if (servname == NULL)
534			return 0;
535			switch (ai->ai_family) {
536			case AF_INET:
537			#ifdef AF_INET6
538			case AF_INET6:
539			#endif
540			break;
541			default:
542			return 0;
543			}
544
545			switch (ai->ai_socktype) {
546			case SOCK_RAW:
547			return EAI_SERVICE;
548			case SOCK_DGRAM:
549			case SOCK_STREAM:
550			allownumeric = 1;
551			break;
552			case ANY:
553			allownumeric = 0;
554			break;
555			default:
556			return EAI_SOCKTYPE;
557			}
558
559			if (str_isnumber(servname)) {
560			if (!allownumeric)
561			return EAI_SERVICE;
562			port = atoi(servname);
563			if (port < 0 \|\| port > 65535)
564			return EAI_SERVICE;
565			port = htons(port);
566			} else {
567			switch (ai->ai_socktype) {
568			case SOCK_DGRAM:
569			proto = "udp";
570			break;
571			case SOCK_STREAM:
572			proto = "tcp";
573			break;
574			default:
575			proto = NULL;
576			break;
577			}
578
579			if ((sp = getservbyname(servname, proto)) == NULL)
580			return EAI_SERVICE;
581			port = sp->s_port;
582			}
583
584			if (!matchonly) {
585			switch (ai->ai_family) {
586			case AF_INET:
587			((struct sockaddr_in )(void )
588			ai->ai_addr)->sin_port = port;
589			break;
590			#ifdef IPV6
591			case AF_INET6:
592			((struct sockaddr_in6 )(void )
593			ai->ai_addr)->sin6_port = port;
594			break;
595			#endif
596			}
597			}
598
599			return 0;
600			}
601
602			static const struct afd *
603			find_afd(int af)
604			{
605			const struct afd *afd;
606
607			if (af == PF_UNSPEC)
608			return(NULL);
609
610			for (afd = afdl; afd->a_af; afd++)
611			{
612			if (afd->a_af == af)
613			return(afd);
614			}
615
616			return(NULL);
617			}