[thirdparty/squid.git] / compat / getnameinfo.cc

/*
 * Copyright (C) 1996-2018 The Squid Software Foundation and contributors
 *
 * Squid software is distributed under GPLv2+ license and includes
 * contributions from numerous individuals and organizations.
 * Please see the COPYING and CONTRIBUTORS files for details.
 */

/*
 *  Shamelessly duplicated from the fetchmail public sources
 *  for use by the Squid Project under GNU Public License.
 *
 * Update/Maintenance History:
 *
 *    16-Aug-2007 : Copied from fetchmail 6.3.8
 *                      - added protection around libray headers
 *                      - added use of alternative name xgetnameinfo
 *                        to split from any OS-provided.
 *
 *    06-Oct-2007 : Various fixes to allow the build on MinGW
 *                      - use srtncpy instead of strlcpy
 *                      - use xinet_ntop instead of inet_ntop
 *                      - use SQUIDHOSTNAMELEN instead of MAXHOSTNAMELEN
 *
 *    13-Jan-2015 : Various fixed for C++ and MinGW native build
 *
 *  Original License and code follows.
 */
#include "squid.h"

/*  KAME: getnameinfo.c,v 1.72 2005/01/13 04:12:03 itojun Exp   */

/*
 * 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.
 */

/*
 * Issues to be discussed:
 * - RFC2553 says that we should raise error on short buffer.  X/Open says
 *   we need to truncate the result.  We obey RFC2553 (and X/Open should be
 *   modified).  ipngwg rough consensus seems to follow RFC2553.  RFC3493 says
 *   nothing about it, but defines a new error code EAI_OVERFLOW which seems
 *   to be intended the code for this case.
 * - What is "local" in NI_NOFQDN?  (see comments in the code)
 * - NI_NAMEREQD and NI_NUMERICHOST conflict with each other.
 * - (KAME extension) always attach textual scopeid (fe80::1%lo0), if
 *   sin6_scope_id is filled - standardization status?
 * - what should we do if we should do getservbyport("sctp")?
 */

/*
 * Considerations about thread-safeness
 *   The code in this file is thread-safe, and so the thread-safeness of
 *   getnameinfo() depends on the property of backend functions.
 *     - getservbyport() is not thread safe for most systems we are targeting.
 *     - getipnodebyaddr() is thread safe.  However, many resolver libraries
 *       used in the function are not thread safe.
 *     - gethostbyaddr() is usually not thread safe.
 */

#if !HAVE_DECL_GETNAMEINFO

#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_NET_IF_H
#include <net/if.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#if HAVE_ARPA_NAMESER_H
#include <arpa/nameser.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#if HAVE_RESOLV_H
#include <resolv.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#endif
#if HAVE_STDDEF_H
#include <stddef.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#if HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#if _SQUID_WINDOWS_
#undef IN_ADDR
#include <ws2tcpip.h>
#endif

static const struct afd {
    int a_af;
    int a_addrlen;
    int a_socklen;
    int a_off;
    int a_portoff;
} afdl [] = {
#if INET6
    {   PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
        offsetof(struct sockaddr_in6, sin6_addr),
        offsetof(struct sockaddr_in6, sin6_port)
    },
#endif
    {   PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
        offsetof(struct sockaddr_in, sin_addr),
        offsetof(struct sockaddr_in, sin_port)
    },
    {0, 0, 0, 0, 0},
};

#if INET6
static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *,
                                 size_t, int));
static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t, int));
#endif

int
xgetnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags)
{
    const struct afd *afd;
    struct servent *sp;
    struct hostent *hp;
    unsigned short port;
    int family, i;
    const char *addr;
    uint32_t v4a;
    char numserv[512];

    if (sa == NULL)
        return EAI_FAIL;

#if HAVE_SA_LEN /*XXX*/
    if (sa->sa_len != salen)
        return EAI_FAIL;
#endif

    family = sa->sa_family;
    for (i = 0; afdl[i].a_af; i++)
        if (afdl[i].a_af == family) {
            afd = &afdl[i];
            goto found;
        }
    return EAI_FAMILY;

found:
    if (salen != afd->a_socklen)
        return EAI_FAIL;

    /* network byte order */
    memcpy(&port, (const char *)sa + afd->a_portoff, sizeof(port));
    addr = (const char *)sa + afd->a_off;

    if (serv == NULL || servlen == 0) {
        /*
         * do nothing in this case.
         * in case you are wondering if "&&" is more correct than
         * "||" here: RFC3493 says that serv == NULL OR servlen == 0
         * means that the caller does not want the result.
         */
    } else {
        if (flags & NI_NUMERICSERV)
            sp = NULL;
        else {
            sp = getservbyport(port,
                               (flags & NI_DGRAM) ? "udp" : "tcp");
        }
        if (sp) {
            if (strlen(sp->s_name) + 1 > servlen)
                return EAI_OVERFLOW;
            strncpy(serv, sp->s_name, servlen);
        } else {
            snprintf(numserv, sizeof(numserv), "%u", ntohs(port));
            if (strlen(numserv) + 1 > servlen)
                return EAI_OVERFLOW;
            strncpy(serv, numserv, servlen);
        }
    }

    switch (sa->sa_family) {
    case AF_INET:
        v4a = (uint32_t)
              ntohl(((const struct sockaddr_in *)sa)->sin_addr.s_addr);
        if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
            flags |= NI_NUMERICHOST;
        v4a >>= IN_CLASSA_NSHIFT;
        if (v4a == 0)
            flags |= NI_NUMERICHOST;
        break;
#if INET6
    case AF_INET6: {
        const struct sockaddr_in6 *sin6;
        sin6 = (const struct sockaddr_in6 *)sa;
        switch (sin6->sin6_addr.s6_addr[0]) {
        case 0x00:
            if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
                ;
            else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
                ;
            else
                flags |= NI_NUMERICHOST;
            break;
        default:
            if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
                flags |= NI_NUMERICHOST;
            else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
                flags |= NI_NUMERICHOST;
            break;
        }
    }
    break;
#endif
    }
    if (host == NULL || hostlen == 0) {
        /*
         * do nothing in this case.
         * in case you are wondering if "&&" is more correct than
         * "||" here: RFC3493 says that host == NULL or hostlen == 0
         * means that the caller does not want the result.
         */
    } else if (flags & NI_NUMERICHOST) {
        /* NUMERICHOST and NAMEREQD conflicts with each other */
        if (flags & NI_NAMEREQD)
            return EAI_NONAME;

        goto numeric;
    } else {
#if USE_GETIPNODEBY
        int h_error = 0;
        hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
#else
        hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
#if 0 // getnameinfo.c:161:9: error: variable 'h_error' set but not used
#if HAVE_H_ERRNO
        h_error = h_errno;
#else
        h_error = EINVAL;
#endif
#endif /* 0 */
#endif

        if (hp) {
#if 0
            if (flags & NI_NOFQDN) {
                /*
                 * According to RFC3493 section 6.2, NI_NOFQDN
                 * means "node name portion of the FQDN shall
                 * be returned for local hosts."  The following
                 * code tries to implement it by returning the
                 * first label (the part before the first
                 * period) of the FQDN.  However, it is not
                 * clear if this always makes sense, since the
                 * given address may be outside of "local
                 * hosts."  Due to the unclear description, we
                 * disable the code in this implementation.
                 */
                char *p;
                p = strchr(hp->h_name, '.');
                if (p)
                    *p = '\0';
            }
#endif
            if (strlen(hp->h_name) + 1 > hostlen) {
#if USE_GETIPNODEBY
                freehostent(hp);
#endif
                return EAI_OVERFLOW;
            }
            strncpy(host, hp->h_name, hostlen);
#if USE_GETIPNODEBY
            freehostent(hp);
#endif
        } else {
            if (flags & NI_NAMEREQD)
                return EAI_NONAME;

numeric:
            switch (afd->a_af) {
#if INET6
            case AF_INET6: {
                int error;

                if ((error = ip6_parsenumeric(sa, addr, host,
                                              hostlen,
                                              flags)) != 0)
                    return(error);
                break;
            }
#endif
            default:
                if (inet_ntop(afd->a_af, addr, host,
                              hostlen) == NULL)
                    return EAI_SYSTEM;
                break;
            }
        }
    }
    return(0);
}

#if INET6
static int
ip6_parsenumeric(sa, addr, host, hostlen, flags)
const struct sockaddr *sa;
const char *addr;
char *host;
size_t hostlen;
int flags;
{
    int numaddrlen;
    char numaddr[512];

    if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr)) == NULL)
        return EAI_SYSTEM;

    numaddrlen = strlen(numaddr);
    if (numaddrlen + 1 > hostlen) /* don't forget terminator */
        return EAI_OVERFLOW;
    strncpy(host, numaddr, hostlen);

    if (((const struct sockaddr_in6 *)sa)->sin6_scope_id) {
        char zonebuf[SQUIDHOSTNAMELEN];
        int zonelen;

        zonelen = ip6_sa2str(
                      (const struct sockaddr_in6 *)(const void *)sa,
                      zonebuf, sizeof(zonebuf), flags);
        if (zonelen < 0)
            return EAI_OVERFLOW;
        if (zonelen + 1 + numaddrlen + 1 > hostlen)
            return EAI_OVERFLOW;

        /* construct <numeric-addr><delim><zoneid> */
        memcpy(host + numaddrlen + 1, zonebuf,
               (size_t)zonelen);
        host[numaddrlen] = SCOPE_DELIMITER;
        host[numaddrlen + 1 + zonelen] = '\0';
    }

    return 0;
}

/* ARGSUSED */
static int
ip6_sa2str(sa6, buf, bufsiz, flags)
const struct sockaddr_in6 *sa6;
char *buf;
size_t bufsiz;
int flags;
{
    unsigned int ifindex;
    const struct in6_addr *a6;
    int n;

    ifindex = (unsigned int)sa6->sin6_scope_id;
    a6 = &sa6->sin6_addr;

#if NI_NUMERICSCOPE
    if ((flags & NI_NUMERICSCOPE) != 0) {
        n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
        if (n < 0 || n >= bufsiz)
            return -1;
        else
            return n;
    }
#endif

    /* if_indextoname() does not take buffer size.  not a good api... */
    if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) ||
            IN6_IS_ADDR_MC_NODELOCAL(a6)) && bufsiz >= IF_NAMESIZE) {
        char *p = if_indextoname(ifindex, buf);
        if (p)
            return (strlen(p));
    }

    /* last resort */
    n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
    if (n < 0 || n >= bufsiz)
        return -1;
    else
        return n;
}
#endif /* INET6 */
#endif /* HAVE_DECL_GETNAMEINFO */
Commit	Line	Data
37be9888	1	/*
5b74111a	2	* Copyright (C) 1996-2018 The Squid Software Foundation and contributors
37be9888 AJ	3	*
	4	* Squid software is distributed under GPLv2+ license and includes
	5	* contributions from numerous individuals and organizations.
	6	* Please see the COPYING and CONTRIBUTORS files for details.
	7	*/
	8
0e076fb1	9	/*
	10	* Shamelessly duplicated from the fetchmail public sources
	11	* for use by the Squid Project under GNU Public License.
	12	*
	13	* Update/Maintenance History:
	14	*
	15	* 16-Aug-2007 : Copied from fetchmail 6.3.8
	16	* - added protection around libray headers
	17	* - added use of alternative name xgetnameinfo
	18	* to split from any OS-provided.
	19	*
	20	* 06-Oct-2007 : Various fixes to allow the build on MinGW
	21	* - use srtncpy instead of strlcpy
	22	* - use xinet_ntop instead of inet_ntop
	23	* - use SQUIDHOSTNAMELEN instead of MAXHOSTNAMELEN
	24	*
d4ddbe05 DF	25	* 13-Jan-2015 : Various fixed for C++ and MinGW native build
d4ddbe05 DF	26	*
0e076fb1	27	* Original License and code follows.
0e076fb1	28	*/
f7f3304a	29	#include "squid.h"
0e076fb1	30
f53969cc	31	/* KAME: getnameinfo.c,v 1.72 2005/01/13 04:12:03 itojun Exp */
0e076fb1	32
	33	/*
	34	* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
	35	* All rights reserved.
	36	*
	37	* Redistribution and use in source and binary forms, with or without
	38	* modification, are permitted provided that the following conditions
	39	* are met:
	40	* 1. Redistributions of source code must retain the above copyright
	41	* notice, this list of conditions and the following disclaimer.
	42	* 2. Redistributions in binary form must reproduce the above copyright
	43	* notice, this list of conditions and the following disclaimer in the
	44	* documentation and/or other materials provided with the distribution.
	45	* 3. Neither the name of the project nor the names of its contributors
	46	* may be used to endorse or promote products derived from this software
	47	* without specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
	50	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	51	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	52	* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
	53	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	54	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	55	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	56	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	57	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	58	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	59	* SUCH DAMAGE.
	60	*/
	61
	62	/*
	63	* Issues to be discussed:
	64	* - RFC2553 says that we should raise error on short buffer. X/Open says
	65	* we need to truncate the result. We obey RFC2553 (and X/Open should be
	66	* modified). ipngwg rough consensus seems to follow RFC2553. RFC3493 says
	67	* nothing about it, but defines a new error code EAI_OVERFLOW which seems
	68	* to be intended the code for this case.
	69	* - What is "local" in NI_NOFQDN? (see comments in the code)
	70	* - NI_NAMEREQD and NI_NUMERICHOST conflict with each other.
	71	* - (KAME extension) always attach textual scopeid (fe80::1%lo0), if
	72	* sin6_scope_id is filled - standardization status?
	73	* - what should we do if we should do getservbyport("sctp")?
	74	*/
	75
	76	/*
	77	* Considerations about thread-safeness
	78	* The code in this file is thread-safe, and so the thread-safeness of
	79	* getnameinfo() depends on the property of backend functions.
	80	* - getservbyport() is not thread safe for most systems we are targeting.
	81	* - getipnodebyaddr() is thread safe. However, many resolver libraries
	82	* used in the function are not thread safe.
	83	* - gethostbyaddr() is usually not thread safe.
	84	*/
	85
55d7d5e9	86	#if !HAVE_DECL_GETNAMEINFO
27bc2077	87
0e076fb1	88	#if HAVE_SYS_SOCKET_H
	89	#include <sys/socket.h>
	90	#endif
	91	#if HAVE_NET_IF_H
	92	#include <net/if.h>
	93	#endif
	94	#if HAVE_NETINET_IN_H
	95	#include <netinet/in.h>
	96	#endif
	97	#if HAVE_ARPA_INET_H
	98	#include <arpa/inet.h>
	99	#endif
	100	#if HAVE_ARPA_NAMESER_H
	101	#include <arpa/nameser.h>
	102	#endif
	103	#if HAVE_NETDB_H
	104	#include <netdb.h>
	105	#endif
	106	#if HAVE_RESOLV_H
	107	#include <resolv.h>
	108	#endif
	109	#if HAVE_STRING_H
	110	#include <string.h>
	111	#endif
	112	#if HAVE_STDDEF_H
	113	#include <stddef.h>
	114	#endif
	115	#if HAVE_ERRNO_H
	116	#include <errno.h>
	117	#endif
	118	#if HAVE_INTTYPES_H
	119	#include <inttypes.h>
	120	#endif
	121
7aa9bb3e	122	#if _SQUID_WINDOWS_
0e076fb1	123	#undef IN_ADDR
	124	#include <ws2tcpip.h>
	125	#endif
	126
0e076fb1	127	static const struct afd {
26ac0430 AJ	128	int a_af;
	129	int a_addrlen;
	130	int a_socklen;
	131	int a_off;
	132	int a_portoff;
0e076fb1	133	} afdl [] = {
32d002cb	134	#if INET6
f53969cc	135	{ PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
26ac0430	136	offsetof(struct sockaddr_in6, sin6_addr),
f53969cc SM	137	offsetof(struct sockaddr_in6, sin6_port)
f53969cc SM	138	},
0e076fb1	139	#endif
f53969cc SM	140	{ PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
	141	offsetof(struct sockaddr_in, sin_addr),
	142	offsetof(struct sockaddr_in, sin_port)
	143	},
26ac0430	144	{0, 0, 0, 0, 0},
0e076fb1	145	};
0e076fb1	146
32d002cb	147	#if INET6
0e076fb1	148	static int ip6_parsenumeric __P((const struct sockaddr , const char , char *,
26ac0430	149	size_t, int));
0e076fb1	150	static int ip6_sa2str __P((const struct sockaddr_in6 , char , size_t, int));
	151	#endif
	152
	153	int
d4ddbe05	154	xgetnameinfo(const struct sockaddr sa, socklen_t salen, char host, size_t hostlen, char *serv, size_t servlen, int flags)
0e076fb1	155	{
26ac0430 AJ	156	const struct afd *afd;
	157	struct servent *sp;
	158	struct hostent *hp;
f45dd259	159	unsigned short port;
26ac0430 AJ	160	int family, i;
26ac0430 AJ	161	const char *addr;
09aabd84	162	uint32_t v4a;
26ac0430 AJ	163	char numserv[512];
	164
	165	if (sa == NULL)
	166	return EAI_FAIL;
0e076fb1	167
f53969cc	168	#if HAVE_SA_LEN /XXX/
26ac0430 AJ	169	if (sa->sa_len != salen)
26ac0430 AJ	170	return EAI_FAIL;
0e076fb1	171	#endif
0e076fb1	172
26ac0430 AJ	173	family = sa->sa_family;
	174	for (i = 0; afdl[i].a_af; i++)
	175	if (afdl[i].a_af == family) {
	176	afd = &afdl[i];
	177	goto found;
	178	}
	179	return EAI_FAMILY;
	180
	181	found:
	182	if (salen != afd->a_socklen)
	183	return EAI_FAIL;
	184
	185	/* network byte order */
	186	memcpy(&port, (const char *)sa + afd->a_portoff, sizeof(port));
	187	addr = (const char *)sa + afd->a_off;
	188
	189	if (serv == NULL \|\| servlen == 0) {
	190	/*
	191	* do nothing in this case.
	192	* in case you are wondering if "&&" is more correct than
	193	* "\|\|" here: RFC3493 says that serv == NULL OR servlen == 0
	194	* means that the caller does not want the result.
	195	*/
	196	} else {
	197	if (flags & NI_NUMERICSERV)
	198	sp = NULL;
	199	else {
	200	sp = getservbyport(port,
	201	(flags & NI_DGRAM) ? "udp" : "tcp");
	202	}
	203	if (sp) {
	204	if (strlen(sp->s_name) + 1 > servlen)
	205	return EAI_OVERFLOW;
	206	strncpy(serv, sp->s_name, servlen);
	207	} else {
	208	snprintf(numserv, sizeof(numserv), "%u", ntohs(port));
	209	if (strlen(numserv) + 1 > servlen)
	210	return EAI_OVERFLOW;
	211	strncpy(serv, numserv, servlen);
	212	}
	213	}
	214
	215	switch (sa->sa_family) {
	216	case AF_INET:
09aabd84	217	v4a = (uint32_t)
26ac0430 AJ	218	ntohl(((const struct sockaddr_in *)sa)->sin_addr.s_addr);
	219	if (IN_MULTICAST(v4a) \|\| IN_EXPERIMENTAL(v4a))
	220	flags \|= NI_NUMERICHOST;
	221	v4a >>= IN_CLASSA_NSHIFT;
	222	if (v4a == 0)
	223	flags \|= NI_NUMERICHOST;
	224	break;
32d002cb	225	#if INET6
26ac0430 AJ	226	case AF_INET6: {
	227	const struct sockaddr_in6 *sin6;
	228	sin6 = (const struct sockaddr_in6 *)sa;
	229	switch (sin6->sin6_addr.s6_addr[0]) {
	230	case 0x00:
	231	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
	232	;
	233	else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
	234	;
	235	else
	236	flags \|= NI_NUMERICHOST;
	237	break;
	238	default:
	239	if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr))
	240	flags \|= NI_NUMERICHOST;
	241	else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
	242	flags \|= NI_NUMERICHOST;
	243	break;
	244	}
	245	}
	246	break;
0e076fb1	247	#endif
26ac0430 AJ	248	}
	249	if (host == NULL \|\| hostlen == 0) {
	250	/*
	251	* do nothing in this case.
	252	* in case you are wondering if "&&" is more correct than
	253	* "\|\|" here: RFC3493 says that host == NULL or hostlen == 0
	254	* means that the caller does not want the result.
	255	*/
	256	} else if (flags & NI_NUMERICHOST) {
	257	/* NUMERICHOST and NAMEREQD conflicts with each other */
	258	if (flags & NI_NAMEREQD)
	259	return EAI_NONAME;
	260
	261	goto numeric;
	262	} else {
32d002cb	263	#if USE_GETIPNODEBY
5b10eaba	264	int h_error = 0;
26ac0430	265	hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
0e076fb1	266	#else
26ac0430	267	hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
5b10eaba	268	#if 0 // getnameinfo.c:161:9: error: variable 'h_error' set but not used
32d002cb	269	#if HAVE_H_ERRNO
26ac0430	270	h_error = h_errno;
0e076fb1	271	#else
26ac0430	272	h_error = EINVAL;
0e076fb1	273	#endif
5b10eaba	274	#endif /* 0 */
0e076fb1	275	#endif
0e076fb1	276
26ac0430	277	if (hp) {
0e076fb1	278	#if 0
26ac0430 AJ	279	if (flags & NI_NOFQDN) {
	280	/*
	281	* According to RFC3493 section 6.2, NI_NOFQDN
	282	* means "node name portion of the FQDN shall
	283	* be returned for local hosts." The following
	284	* code tries to implement it by returning the
	285	* first label (the part before the first
	286	* period) of the FQDN. However, it is not
	287	* clear if this always makes sense, since the
	288	* given address may be outside of "local
	289	* hosts." Due to the unclear description, we
	290	* disable the code in this implementation.
	291	*/
	292	char *p;
	293	p = strchr(hp->h_name, '.');
	294	if (p)
	295	*p = '\0';
	296	}
0e076fb1	297	#endif
26ac0430	298	if (strlen(hp->h_name) + 1 > hostlen) {
32d002cb	299	#if USE_GETIPNODEBY
26ac0430	300	freehostent(hp);
0e076fb1	301	#endif
26ac0430 AJ	302	return EAI_OVERFLOW;
	303	}
	304	strncpy(host, hp->h_name, hostlen);
32d002cb	305	#if USE_GETIPNODEBY
26ac0430	306	freehostent(hp);
0e076fb1	307	#endif
26ac0430 AJ	308	} else {
	309	if (flags & NI_NAMEREQD)
	310	return EAI_NONAME;
0e076fb1	311
26ac0430 AJ	312	numeric:
26ac0430 AJ	313	switch (afd->a_af) {
32d002cb	314	#if INET6
26ac0430 AJ	315	case AF_INET6: {
	316	int error;
	317
	318	if ((error = ip6_parsenumeric(sa, addr, host,
	319	hostlen,
	320	flags)) != 0)
	321	return(error);
	322	break;
	323	}
0e076fb1	324	#endif
26ac0430	325	default:
27bc2077	326	if (inet_ntop(afd->a_af, addr, host,
b1c8a478	327	hostlen) == NULL)
26ac0430 AJ	328	return EAI_SYSTEM;
	329	break;
	330	}
	331	}
	332	}
	333	return(0);
0e076fb1	334	}
0e076fb1	335
32d002cb	336	#if INET6
0e076fb1	337	static int
0e076fb1	338	ip6_parsenumeric(sa, addr, host, hostlen, flags)
26ac0430 AJ	339	const struct sockaddr *sa;
	340	const char *addr;
	341	char *host;
	342	size_t hostlen;
	343	int flags;
0e076fb1	344	{
26ac0430 AJ	345	int numaddrlen;
	346	char numaddr[512];
	347
27bc2077	348	if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr)) == NULL)
26ac0430 AJ	349	return EAI_SYSTEM;
	350
	351	numaddrlen = strlen(numaddr);
	352	if (numaddrlen + 1 > hostlen) /* don't forget terminator */
	353	return EAI_OVERFLOW;
	354	strncpy(host, numaddr, hostlen);
	355
	356	if (((const struct sockaddr_in6 *)sa)->sin6_scope_id) {
	357	char zonebuf[SQUIDHOSTNAMELEN];
	358	int zonelen;
	359
	360	zonelen = ip6_sa2str(
	361	(const struct sockaddr_in6 )(const void )sa,
	362	zonebuf, sizeof(zonebuf), flags);
	363	if (zonelen < 0)
	364	return EAI_OVERFLOW;
	365	if (zonelen + 1 + numaddrlen + 1 > hostlen)
	366	return EAI_OVERFLOW;
	367
	368	/* construct <numeric-addr><delim><zoneid> */
	369	memcpy(host + numaddrlen + 1, zonebuf,
	370	(size_t)zonelen);
	371	host[numaddrlen] = SCOPE_DELIMITER;
	372	host[numaddrlen + 1 + zonelen] = '\0';
	373	}
	374
	375	return 0;
0e076fb1	376	}
	377
	378	/* ARGSUSED */
	379	static int
	380	ip6_sa2str(sa6, buf, bufsiz, flags)
26ac0430 AJ	381	const struct sockaddr_in6 *sa6;
	382	char *buf;
	383	size_t bufsiz;
	384	int flags;
0e076fb1	385	{
26ac0430 AJ	386	unsigned int ifindex;
	387	const struct in6_addr *a6;
	388	int n;
0e076fb1	389
26ac0430 AJ	390	ifindex = (unsigned int)sa6->sin6_scope_id;
26ac0430 AJ	391	a6 = &sa6->sin6_addr;
0e076fb1	392
32d002cb	393	#if NI_NUMERICSCOPE
26ac0430 AJ	394	if ((flags & NI_NUMERICSCOPE) != 0) {
	395	n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
	396	if (n < 0 \|\| n >= bufsiz)
	397	return -1;
	398	else
	399	return n;
	400	}
0e076fb1	401	#endif
0e076fb1	402
26ac0430 AJ	403	/* if_indextoname() does not take buffer size. not a good api... */
	404	if ((IN6_IS_ADDR_LINKLOCAL(a6) \|\| IN6_IS_ADDR_MC_LINKLOCAL(a6) \|\|
	405	IN6_IS_ADDR_MC_NODELOCAL(a6)) && bufsiz >= IF_NAMESIZE) {
	406	char *p = if_indextoname(ifindex, buf);
	407	if (p)
	408	return (strlen(p));
	409	}
	410
	411	/* last resort */
	412	n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
	413	if (n < 0 \|\| n >= bufsiz)
	414	return -1;
	415	else
	416	return n;
0e076fb1	417	}
0e076fb1	418	#endif /* INET6 */
55d7d5e9	419	#endif /* HAVE_DECL_GETNAMEINFO */
f53969cc	420