mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-25 11:37:56 +00:00
2849 lines
65 KiB
C
2849 lines
65 KiB
C
/* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */
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/*
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* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the project nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator.
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*
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* Issues to be discussed:
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* - Return values. There are nonstandard return values defined and used
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* in the source code. This is because RFC2553 is silent about which error
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* code must be returned for which situation.
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* - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is
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* invalid. current code - SEGV on freeaddrinfo(NULL)
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*
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* Note:
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* - The code filters out AFs that are not supported by the kernel,
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* when globbing NULL hostname (to loopback, or wildcard). Is it the right
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* thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG
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* in ai_flags?
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* - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
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* (1) what should we do against numeric hostname (2) what should we do
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* against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready?
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* non-loopback address configured? global address configured?
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*
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* OS specific notes for freebsd4:
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* - FreeBSD supported $GAI. The code does not.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "namespace.h"
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/socket.h>
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#include <net/if.h>
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#include <netinet/in.h>
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#include <sys/queue.h>
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#ifdef INET6
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#include <net/if_var.h>
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#include <sys/sysctl.h>
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#include <sys/ioctl.h>
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#include <netinet6/in6_var.h> /* XXX */
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#endif
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#include <arpa/inet.h>
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#include <arpa/nameser.h>
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#include <rpc/rpc.h>
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#include <rpcsvc/yp_prot.h>
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#include <rpcsvc/ypclnt.h>
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#include <netdb.h>
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#include <resolv.h>
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#include <string.h>
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#include <stdlib.h>
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#include <stddef.h>
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#include <ctype.h>
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#include <unistd.h>
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#include <stdio.h>
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#include <errno.h>
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#include "res_config.h"
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#ifdef DEBUG
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#include <syslog.h>
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#endif
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#include <stdarg.h>
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#include <nsswitch.h>
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#include "un-namespace.h"
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#include "libc_private.h"
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#ifdef NS_CACHING
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#include "nscache.h"
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#endif
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#if defined(__KAME__) && defined(INET6)
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# define FAITH
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#endif
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#define ANY 0
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#define YES 1
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#define NO 0
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static const char in_addrany[] = { 0, 0, 0, 0 };
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static const char in_loopback[] = { 127, 0, 0, 1 };
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#ifdef INET6
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static const char in6_addrany[] = {
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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};
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static const char in6_loopback[] = {
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
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};
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#endif
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struct policyqueue {
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TAILQ_ENTRY(policyqueue) pc_entry;
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#ifdef INET6
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struct in6_addrpolicy pc_policy;
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#endif
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};
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TAILQ_HEAD(policyhead, policyqueue);
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static const struct afd {
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int a_af;
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int a_addrlen;
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socklen_t a_socklen;
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int a_off;
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const char *a_addrany;
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const char *a_loopback;
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int a_scoped;
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} afdl [] = {
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#ifdef INET6
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#define N_INET6 0
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{PF_INET6, sizeof(struct in6_addr),
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sizeof(struct sockaddr_in6),
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offsetof(struct sockaddr_in6, sin6_addr),
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in6_addrany, in6_loopback, 1},
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#define N_INET 1
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#else
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#define N_INET 0
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#endif
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{PF_INET, sizeof(struct in_addr),
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sizeof(struct sockaddr_in),
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offsetof(struct sockaddr_in, sin_addr),
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in_addrany, in_loopback, 0},
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{0, 0, 0, 0, NULL, NULL, 0},
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};
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struct explore {
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int e_af;
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int e_socktype;
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int e_protocol;
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int e_wild;
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#define WILD_AF(ex) ((ex)->e_wild & 0x01)
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#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
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#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
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};
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static const struct explore explore[] = {
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#if 0
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{ PF_LOCAL, ANY, ANY, 0x01 },
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#endif
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#ifdef INET6
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{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
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{ PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 },
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{ PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
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{ PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
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{ PF_INET6, SOCK_RAW, ANY, 0x05 },
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#endif
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{ PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
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{ PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 },
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{ PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
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{ PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
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{ PF_INET, SOCK_RAW, ANY, 0x05 },
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{ -1, 0, 0, 0 },
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};
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#ifdef INET6
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#define PTON_MAX 16
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#else
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#define PTON_MAX 4
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#endif
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#define AIO_SRCFLAG_DEPRECATED 0x1
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struct ai_order {
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union {
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struct sockaddr_storage aiou_ss;
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struct sockaddr aiou_sa;
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} aio_src_un;
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#define aio_srcsa aio_src_un.aiou_sa
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u_int32_t aio_srcflag;
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int aio_srcscope;
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int aio_dstscope;
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struct policyqueue *aio_srcpolicy;
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struct policyqueue *aio_dstpolicy;
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struct addrinfo *aio_ai;
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int aio_matchlen;
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};
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static const ns_src default_dns_files[] = {
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{ NSSRC_FILES, NS_SUCCESS },
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{ NSSRC_DNS, NS_SUCCESS },
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{ 0 }
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};
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struct res_target {
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struct res_target *next;
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const char *name; /* domain name */
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int qclass, qtype; /* class and type of query */
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u_char *answer; /* buffer to put answer */
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int anslen; /* size of answer buffer */
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int n; /* result length */
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};
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#define MAXPACKET (64*1024)
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typedef union {
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HEADER hdr;
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u_char buf[MAXPACKET];
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} querybuf;
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static int str2number(const char *, int *);
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static int explore_copy(const struct addrinfo *, const struct addrinfo *,
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struct addrinfo **);
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static int explore_null(const struct addrinfo *,
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const char *, struct addrinfo **);
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static int explore_numeric(const struct addrinfo *, const char *,
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const char *, struct addrinfo **, const char *);
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static int explore_numeric_scope(const struct addrinfo *, const char *,
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const char *, struct addrinfo **);
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static int get_canonname(const struct addrinfo *,
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struct addrinfo *, const char *);
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static struct addrinfo *get_ai(const struct addrinfo *,
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const struct afd *, const char *);
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static struct addrinfo *copy_ai(const struct addrinfo *);
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static int get_portmatch(const struct addrinfo *, const char *);
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static int get_port(struct addrinfo *, const char *, int);
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static const struct afd *find_afd(int);
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static int addrconfig(struct addrinfo *);
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static void set_source(struct ai_order *, struct policyhead *);
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static int comp_dst(const void *, const void *);
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#ifdef INET6
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static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
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#endif
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static int gai_addr2scopetype(struct sockaddr *);
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static int explore_fqdn(const struct addrinfo *, const char *,
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const char *, struct addrinfo **);
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static int reorder(struct addrinfo *);
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static int get_addrselectpolicy(struct policyhead *);
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static void free_addrselectpolicy(struct policyhead *);
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static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
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struct policyhead *);
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static int matchlen(struct sockaddr *, struct sockaddr *);
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static struct addrinfo *getanswer(const querybuf *, int, const char *, int,
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const struct addrinfo *, res_state);
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#if defined(RESOLVSORT)
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static int addr4sort(struct addrinfo *, res_state);
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#endif
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static int _dns_getaddrinfo(void *, void *, va_list);
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static void _sethtent(FILE **);
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static void _endhtent(FILE **);
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static struct addrinfo *_gethtent(FILE **, const char *,
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const struct addrinfo *);
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static int _files_getaddrinfo(void *, void *, va_list);
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#ifdef YP
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static struct addrinfo *_yphostent(char *, const struct addrinfo *);
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static int _yp_getaddrinfo(void *, void *, va_list);
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#endif
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#ifdef NS_CACHING
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static int addrinfo_id_func(char *, size_t *, va_list, void *);
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static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *);
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static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *);
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#endif
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static int res_queryN(const char *, struct res_target *, res_state);
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static int res_searchN(const char *, struct res_target *, res_state);
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static int res_querydomainN(const char *, const char *,
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struct res_target *, res_state);
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/* XXX macros that make external reference is BAD. */
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#define GET_AI(ai, afd, addr) \
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do { \
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/* external reference: pai, error, and label free */ \
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(ai) = get_ai(pai, (afd), (addr)); \
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if ((ai) == NULL) { \
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error = EAI_MEMORY; \
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goto free; \
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} \
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} while (/*CONSTCOND*/0)
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#define GET_PORT(ai, serv) \
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do { \
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/* external reference: error and label free */ \
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error = get_port((ai), (serv), 0); \
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if (error != 0) \
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goto free; \
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} while (/*CONSTCOND*/0)
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#define GET_CANONNAME(ai, str) \
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do { \
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/* external reference: pai, error and label free */ \
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error = get_canonname(pai, (ai), (str)); \
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if (error != 0) \
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goto free; \
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} while (/*CONSTCOND*/0)
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#define ERR(err) \
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do { \
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/* external reference: error, and label bad */ \
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error = (err); \
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goto bad; \
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/*NOTREACHED*/ \
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} while (/*CONSTCOND*/0)
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#define MATCH_FAMILY(x, y, w) \
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((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
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#define MATCH(x, y, w) \
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((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
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void
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freeaddrinfo(struct addrinfo *ai)
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{
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struct addrinfo *next;
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do {
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next = ai->ai_next;
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if (ai->ai_canonname)
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free(ai->ai_canonname);
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/* no need to free(ai->ai_addr) */
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free(ai);
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ai = next;
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} while (ai);
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}
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static int
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str2number(const char *p, int *portp)
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{
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char *ep;
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unsigned long v;
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if (*p == '\0')
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return -1;
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ep = NULL;
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errno = 0;
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v = strtoul(p, &ep, 10);
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if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) {
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*portp = v;
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return 0;
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} else
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return -1;
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}
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int
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getaddrinfo(const char *hostname, const char *servname,
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const struct addrinfo *hints, struct addrinfo **res)
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{
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struct addrinfo sentinel;
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struct addrinfo *cur;
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int error = 0;
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struct addrinfo ai, ai0, *afai;
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struct addrinfo *pai;
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const struct afd *afd;
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const struct explore *ex;
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struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])];
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struct addrinfo *afai_unspec;
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int found;
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int numeric = 0;
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/* ensure we return NULL on errors */
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*res = NULL;
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memset(&ai, 0, sizeof(ai));
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memset(afailist, 0, sizeof(afailist));
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afai_unspec = NULL;
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memset(&sentinel, 0, sizeof(sentinel));
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cur = &sentinel;
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pai = &ai;
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pai->ai_flags = 0;
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pai->ai_family = PF_UNSPEC;
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pai->ai_socktype = ANY;
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pai->ai_protocol = ANY;
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pai->ai_addrlen = 0;
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pai->ai_canonname = NULL;
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pai->ai_addr = NULL;
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pai->ai_next = NULL;
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if (hostname == NULL && servname == NULL)
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return EAI_NONAME;
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if (hints) {
|
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/* error check for hints */
|
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if (hints->ai_addrlen || hints->ai_canonname ||
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hints->ai_addr || hints->ai_next)
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ERR(EAI_BADHINTS); /* xxx */
|
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if (hints->ai_flags & ~AI_MASK)
|
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ERR(EAI_BADFLAGS);
|
|
switch (hints->ai_family) {
|
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case PF_UNSPEC:
|
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case PF_INET:
|
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#ifdef INET6
|
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case PF_INET6:
|
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#endif
|
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break;
|
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default:
|
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ERR(EAI_FAMILY);
|
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}
|
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memcpy(pai, hints, sizeof(*pai));
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|
|
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/*
|
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* if both socktype/protocol are specified, check if they
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* are meaningful combination.
|
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*/
|
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if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
|
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for (ex = explore; ex->e_af >= 0; ex++) {
|
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if (!MATCH_FAMILY(pai->ai_family, ex->e_af,
|
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WILD_AF(ex)))
|
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continue;
|
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if (!MATCH(pai->ai_socktype, ex->e_socktype,
|
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WILD_SOCKTYPE(ex)))
|
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continue;
|
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if (!MATCH(pai->ai_protocol, ex->e_protocol,
|
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WILD_PROTOCOL(ex)))
|
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continue;
|
|
|
|
/* matched */
|
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break;
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}
|
|
|
|
if (ex->e_af < 0)
|
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ERR(EAI_BADHINTS);
|
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}
|
|
}
|
|
|
|
/*
|
|
* check for special cases. (1) numeric servname is disallowed if
|
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* 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)
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#ifdef PF_INET6
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|| MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
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#endif
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) {
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ai0 = *pai; /* backup *pai */
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|
|
|
if (pai->ai_family == PF_UNSPEC) {
|
|
#ifdef PF_INET6
|
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pai->ai_family = PF_INET6;
|
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#else
|
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pai->ai_family = PF_INET;
|
|
#endif
|
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}
|
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error = get_portmatch(pai, servname);
|
|
if (error)
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goto bad;
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|
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*pai = ai0;
|
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}
|
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|
|
ai0 = *pai;
|
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|
|
/*
|
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* NULL hostname, or numeric hostname.
|
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* If numeric representation of AF1 can be interpreted as FQDN
|
|
* representation of AF2, we need to think again about the code below.
|
|
*/
|
|
found = 0;
|
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for (afd = afdl; afd->a_af; afd++) {
|
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*pai = ai0;
|
|
|
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if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1))
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continue;
|
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|
|
if (pai->ai_family == PF_UNSPEC)
|
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pai->ai_family = afd->a_af;
|
|
|
|
if (hostname == NULL) {
|
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error = explore_null(pai, servname,
|
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&afailist[afd - afdl]);
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|
|
|
/*
|
|
* Errors from explore_null should be unexpected and
|
|
* be caught to avoid returning an incomplete result.
|
|
*/
|
|
if (error != 0)
|
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goto bad;
|
|
} else {
|
|
error = explore_numeric_scope(pai, hostname, servname,
|
|
&afailist[afd - afdl]);
|
|
|
|
/*
|
|
* explore_numeric_scope returns an error for address
|
|
* families that do not match that of hostname.
|
|
* Thus we should not catch the error at this moment.
|
|
*/
|
|
}
|
|
|
|
if (!error && afailist[afd - afdl])
|
|
found++;
|
|
}
|
|
if (found) {
|
|
numeric = 1;
|
|
goto globcopy;
|
|
}
|
|
|
|
if (hostname == NULL)
|
|
ERR(EAI_NONAME); /* used to be EAI_NODATA */
|
|
if (pai->ai_flags & AI_NUMERICHOST)
|
|
ERR(EAI_NONAME);
|
|
|
|
if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
|
|
ERR(EAI_FAIL);
|
|
|
|
/*
|
|
* hostname as alphabetical name.
|
|
*/
|
|
*pai = ai0;
|
|
error = explore_fqdn(pai, hostname, servname, &afai_unspec);
|
|
|
|
globcopy:
|
|
for (ex = explore; ex->e_af >= 0; ex++) {
|
|
*pai = ai0;
|
|
|
|
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 the servname does not match socktype/protocol, ignore it.
|
|
*/
|
|
if (get_portmatch(pai, servname) != 0)
|
|
continue;
|
|
|
|
if (afai_unspec)
|
|
afai = afai_unspec;
|
|
else {
|
|
if ((afd = find_afd(pai->ai_family)) == NULL)
|
|
continue;
|
|
/* XXX assumes that afd points inside afdl[] */
|
|
afai = afailist[afd - afdl];
|
|
}
|
|
if (!afai)
|
|
continue;
|
|
|
|
error = explore_copy(pai, afai, &cur->ai_next);
|
|
if (error != 0)
|
|
goto bad;
|
|
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
}
|
|
|
|
/*
|
|
* ensure we return either:
|
|
* - error == 0, non-NULL *res
|
|
* - error != 0, NULL *res
|
|
*/
|
|
if (error == 0) {
|
|
if (sentinel.ai_next) {
|
|
/*
|
|
* If the returned entry is for an active connection,
|
|
* and the given name is not numeric, reorder the
|
|
* list, so that the application would try the list
|
|
* in the most efficient order. Since the head entry
|
|
* of the original list may contain ai_canonname and
|
|
* that entry may be moved elsewhere in the new list,
|
|
* we keep the pointer and will restore it in the new
|
|
* head entry. (Note that RFC3493 requires the head
|
|
* entry store it when requested by the caller).
|
|
*/
|
|
if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
|
|
if (!numeric) {
|
|
char *canonname;
|
|
|
|
canonname =
|
|
sentinel.ai_next->ai_canonname;
|
|
sentinel.ai_next->ai_canonname = NULL;
|
|
(void)reorder(&sentinel);
|
|
if (sentinel.ai_next->ai_canonname ==
|
|
NULL) {
|
|
sentinel.ai_next->ai_canonname
|
|
= canonname;
|
|
} else if (canonname != NULL)
|
|
free(canonname);
|
|
}
|
|
}
|
|
*res = sentinel.ai_next;
|
|
} else
|
|
error = EAI_FAIL;
|
|
}
|
|
|
|
bad:
|
|
if (afai_unspec)
|
|
freeaddrinfo(afai_unspec);
|
|
for (afd = afdl; afd->a_af; afd++) {
|
|
if (afailist[afd - afdl])
|
|
freeaddrinfo(afailist[afd - afdl]);
|
|
}
|
|
if (!*res)
|
|
if (sentinel.ai_next)
|
|
freeaddrinfo(sentinel.ai_next);
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
reorder(struct addrinfo *sentinel)
|
|
{
|
|
struct addrinfo *ai, **aip;
|
|
struct ai_order *aio;
|
|
int i, n;
|
|
struct policyhead policyhead;
|
|
|
|
/* count the number of addrinfo elements for sorting. */
|
|
for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
|
|
;
|
|
|
|
/*
|
|
* If the number is small enough, we can skip the reordering process.
|
|
*/
|
|
if (n <= 1)
|
|
return(n);
|
|
|
|
/* allocate a temporary array for sort and initialization of it. */
|
|
if ((aio = malloc(sizeof(*aio) * n)) == NULL)
|
|
return(n); /* give up reordering */
|
|
memset(aio, 0, sizeof(*aio) * n);
|
|
|
|
/* retrieve address selection policy from the kernel */
|
|
TAILQ_INIT(&policyhead);
|
|
if (!get_addrselectpolicy(&policyhead)) {
|
|
/* no policy is installed into kernel, we don't sort. */
|
|
free(aio);
|
|
return (n);
|
|
}
|
|
|
|
for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
|
|
aio[i].aio_ai = ai;
|
|
aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
|
|
aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
|
|
&policyhead);
|
|
set_source(&aio[i], &policyhead);
|
|
}
|
|
|
|
/* perform sorting. */
|
|
qsort(aio, n, sizeof(*aio), comp_dst);
|
|
|
|
/* reorder the addrinfo chain. */
|
|
for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
|
|
*aip = aio[i].aio_ai;
|
|
aip = &aio[i].aio_ai->ai_next;
|
|
}
|
|
*aip = NULL;
|
|
|
|
/* cleanup and return */
|
|
free(aio);
|
|
free_addrselectpolicy(&policyhead);
|
|
return(n);
|
|
}
|
|
|
|
static int
|
|
get_addrselectpolicy(struct policyhead *head)
|
|
{
|
|
#ifdef INET6
|
|
int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
|
|
size_t l;
|
|
char *buf;
|
|
struct in6_addrpolicy *pol, *ep;
|
|
|
|
if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0)
|
|
return (0);
|
|
if (l == 0)
|
|
return (0);
|
|
if ((buf = malloc(l)) == NULL)
|
|
return (0);
|
|
if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) {
|
|
free(buf);
|
|
return (0);
|
|
}
|
|
|
|
ep = (struct in6_addrpolicy *)(buf + l);
|
|
for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
|
|
struct policyqueue *new;
|
|
|
|
if ((new = malloc(sizeof(*new))) == NULL) {
|
|
free_addrselectpolicy(head); /* make the list empty */
|
|
break;
|
|
}
|
|
new->pc_policy = *pol;
|
|
TAILQ_INSERT_TAIL(head, new, pc_entry);
|
|
}
|
|
|
|
free(buf);
|
|
return (1);
|
|
#else
|
|
return (0);
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
free_addrselectpolicy(struct policyhead *head)
|
|
{
|
|
struct policyqueue *ent, *nent;
|
|
|
|
for (ent = TAILQ_FIRST(head); ent; ent = nent) {
|
|
nent = TAILQ_NEXT(ent, pc_entry);
|
|
TAILQ_REMOVE(head, ent, pc_entry);
|
|
free(ent);
|
|
}
|
|
}
|
|
|
|
static struct policyqueue *
|
|
match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
|
|
{
|
|
#ifdef INET6
|
|
struct policyqueue *ent, *bestent = NULL;
|
|
struct in6_addrpolicy *pol;
|
|
int matchlen, bestmatchlen = -1;
|
|
u_char *mp, *ep, *k, *p, m;
|
|
struct sockaddr_in6 key;
|
|
|
|
switch(addr->sa_family) {
|
|
case AF_INET6:
|
|
key = *(struct sockaddr_in6 *)addr;
|
|
break;
|
|
case AF_INET:
|
|
/* convert the address into IPv4-mapped IPv6 address. */
|
|
memset(&key, 0, sizeof(key));
|
|
key.sin6_family = AF_INET6;
|
|
key.sin6_len = sizeof(key);
|
|
key.sin6_addr.s6_addr[10] = 0xff;
|
|
key.sin6_addr.s6_addr[11] = 0xff;
|
|
memcpy(&key.sin6_addr.s6_addr[12],
|
|
&((struct sockaddr_in *)addr)->sin_addr, 4);
|
|
break;
|
|
default:
|
|
return(NULL);
|
|
}
|
|
|
|
for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
|
|
pol = &ent->pc_policy;
|
|
matchlen = 0;
|
|
|
|
mp = (u_char *)&pol->addrmask.sin6_addr;
|
|
ep = mp + 16; /* XXX: scope field? */
|
|
k = (u_char *)&key.sin6_addr;
|
|
p = (u_char *)&pol->addr.sin6_addr;
|
|
for (; mp < ep && *mp; mp++, k++, p++) {
|
|
m = *mp;
|
|
if ((*k & m) != *p)
|
|
goto next; /* not match */
|
|
if (m == 0xff) /* short cut for a typical case */
|
|
matchlen += 8;
|
|
else {
|
|
while (m >= 0x80) {
|
|
matchlen++;
|
|
m <<= 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* matched. check if this is better than the current best. */
|
|
if (matchlen > bestmatchlen) {
|
|
bestent = ent;
|
|
bestmatchlen = matchlen;
|
|
}
|
|
|
|
next:
|
|
continue;
|
|
}
|
|
|
|
return(bestent);
|
|
#else
|
|
return(NULL);
|
|
#endif
|
|
|
|
}
|
|
|
|
static void
|
|
set_source(struct ai_order *aio, struct policyhead *ph)
|
|
{
|
|
struct addrinfo ai = *aio->aio_ai;
|
|
struct sockaddr_storage ss;
|
|
socklen_t srclen;
|
|
int s;
|
|
|
|
/* set unspec ("no source is available"), just in case */
|
|
aio->aio_srcsa.sa_family = AF_UNSPEC;
|
|
aio->aio_srcscope = -1;
|
|
|
|
switch(ai.ai_family) {
|
|
case AF_INET:
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
#endif
|
|
break;
|
|
default: /* ignore unsupported AFs explicitly */
|
|
return;
|
|
}
|
|
|
|
/* XXX: make a dummy addrinfo to call connect() */
|
|
ai.ai_socktype = SOCK_DGRAM;
|
|
ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
|
|
ai.ai_next = NULL;
|
|
memset(&ss, 0, sizeof(ss));
|
|
memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
|
|
ai.ai_addr = (struct sockaddr *)&ss;
|
|
get_port(&ai, "1", 0);
|
|
|
|
/* open a socket to get the source address for the given dst */
|
|
if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0)
|
|
return; /* give up */
|
|
if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
|
|
goto cleanup;
|
|
srclen = ai.ai_addrlen;
|
|
if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
|
|
aio->aio_srcsa.sa_family = AF_UNSPEC;
|
|
goto cleanup;
|
|
}
|
|
aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
|
|
aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
|
|
aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
|
|
#ifdef INET6
|
|
if (ai.ai_family == AF_INET6) {
|
|
struct in6_ifreq ifr6;
|
|
u_int32_t flags6;
|
|
|
|
memset(&ifr6, 0, sizeof(ifr6));
|
|
memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
|
|
if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
|
|
flags6 = ifr6.ifr_ifru.ifru_flags6;
|
|
if ((flags6 & IN6_IFF_DEPRECATED))
|
|
aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
cleanup:
|
|
_close(s);
|
|
return;
|
|
}
|
|
|
|
static int
|
|
matchlen(struct sockaddr *src, struct sockaddr *dst)
|
|
{
|
|
int match = 0;
|
|
u_char *s, *d;
|
|
u_char *lim, r;
|
|
int addrlen;
|
|
|
|
switch (src->sa_family) {
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
|
|
d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
|
|
addrlen = sizeof(struct in6_addr);
|
|
lim = s + addrlen;
|
|
break;
|
|
#endif
|
|
case AF_INET:
|
|
s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
|
|
d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
|
|
addrlen = sizeof(struct in_addr);
|
|
lim = s + addrlen;
|
|
break;
|
|
default:
|
|
return(0);
|
|
}
|
|
|
|
while (s < lim)
|
|
if ((r = (*d++ ^ *s++)) != 0) {
|
|
while (r < addrlen * 8) {
|
|
match++;
|
|
r <<= 1;
|
|
}
|
|
break;
|
|
} else
|
|
match += 8;
|
|
return(match);
|
|
}
|
|
|
|
static int
|
|
comp_dst(const void *arg1, const void *arg2)
|
|
{
|
|
const struct ai_order *dst1 = arg1, *dst2 = arg2;
|
|
|
|
/*
|
|
* Rule 1: Avoid unusable destinations.
|
|
* XXX: we currently do not consider if an appropriate route exists.
|
|
*/
|
|
if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
|
|
dst2->aio_srcsa.sa_family == AF_UNSPEC) {
|
|
return(-1);
|
|
}
|
|
if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
|
|
dst2->aio_srcsa.sa_family != AF_UNSPEC) {
|
|
return(1);
|
|
}
|
|
|
|
/* Rule 2: Prefer matching scope. */
|
|
if (dst1->aio_dstscope == dst1->aio_srcscope &&
|
|
dst2->aio_dstscope != dst2->aio_srcscope) {
|
|
return(-1);
|
|
}
|
|
if (dst1->aio_dstscope != dst1->aio_srcscope &&
|
|
dst2->aio_dstscope == dst2->aio_srcscope) {
|
|
return(1);
|
|
}
|
|
|
|
/* Rule 3: Avoid deprecated addresses. */
|
|
if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
|
|
dst2->aio_srcsa.sa_family != AF_UNSPEC) {
|
|
if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
|
|
(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
|
|
return(-1);
|
|
}
|
|
if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
|
|
!(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
|
|
return(1);
|
|
}
|
|
}
|
|
|
|
/* Rule 4: Prefer home addresses. */
|
|
/* XXX: not implemented yet */
|
|
|
|
/* Rule 5: Prefer matching label. */
|
|
#ifdef INET6
|
|
if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
|
|
dst1->aio_srcpolicy->pc_policy.label ==
|
|
dst1->aio_dstpolicy->pc_policy.label &&
|
|
(dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
|
|
dst2->aio_srcpolicy->pc_policy.label !=
|
|
dst2->aio_dstpolicy->pc_policy.label)) {
|
|
return(-1);
|
|
}
|
|
if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
|
|
dst2->aio_srcpolicy->pc_policy.label ==
|
|
dst2->aio_dstpolicy->pc_policy.label &&
|
|
(dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
|
|
dst1->aio_srcpolicy->pc_policy.label !=
|
|
dst1->aio_dstpolicy->pc_policy.label)) {
|
|
return(1);
|
|
}
|
|
#endif
|
|
|
|
/* Rule 6: Prefer higher precedence. */
|
|
#ifdef INET6
|
|
if (dst1->aio_dstpolicy &&
|
|
(dst2->aio_dstpolicy == NULL ||
|
|
dst1->aio_dstpolicy->pc_policy.preced >
|
|
dst2->aio_dstpolicy->pc_policy.preced)) {
|
|
return(-1);
|
|
}
|
|
if (dst2->aio_dstpolicy &&
|
|
(dst1->aio_dstpolicy == NULL ||
|
|
dst2->aio_dstpolicy->pc_policy.preced >
|
|
dst1->aio_dstpolicy->pc_policy.preced)) {
|
|
return(1);
|
|
}
|
|
#endif
|
|
|
|
/* Rule 7: Prefer native transport. */
|
|
/* XXX: not implemented yet */
|
|
|
|
/* Rule 8: Prefer smaller scope. */
|
|
if (dst1->aio_dstscope >= 0 &&
|
|
dst1->aio_dstscope < dst2->aio_dstscope) {
|
|
return(-1);
|
|
}
|
|
if (dst2->aio_dstscope >= 0 &&
|
|
dst2->aio_dstscope < dst1->aio_dstscope) {
|
|
return(1);
|
|
}
|
|
|
|
/*
|
|
* Rule 9: Use longest matching prefix.
|
|
* We compare the match length in a same AF only.
|
|
*/
|
|
if (dst1->aio_ai->ai_addr->sa_family ==
|
|
dst2->aio_ai->ai_addr->sa_family) {
|
|
if (dst1->aio_matchlen > dst2->aio_matchlen) {
|
|
return(-1);
|
|
}
|
|
if (dst1->aio_matchlen < dst2->aio_matchlen) {
|
|
return(1);
|
|
}
|
|
}
|
|
|
|
/* Rule 10: Otherwise, leave the order unchanged. */
|
|
return(-1);
|
|
}
|
|
|
|
/*
|
|
* Copy from scope.c.
|
|
* XXX: we should standardize the functions and link them as standard
|
|
* library.
|
|
*/
|
|
static int
|
|
gai_addr2scopetype(struct sockaddr *sa)
|
|
{
|
|
#ifdef INET6
|
|
struct sockaddr_in6 *sa6;
|
|
#endif
|
|
struct sockaddr_in *sa4;
|
|
|
|
switch(sa->sa_family) {
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
sa6 = (struct sockaddr_in6 *)sa;
|
|
if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
|
|
/* just use the scope field of the multicast address */
|
|
return(sa6->sin6_addr.s6_addr[2] & 0x0f);
|
|
}
|
|
/*
|
|
* Unicast addresses: map scope type to corresponding scope
|
|
* value defined for multcast addresses.
|
|
* XXX: hardcoded scope type values are bad...
|
|
*/
|
|
if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
|
|
return(1); /* node local scope */
|
|
if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
|
|
return(2); /* link-local scope */
|
|
if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
|
|
return(5); /* site-local scope */
|
|
return(14); /* global scope */
|
|
break;
|
|
#endif
|
|
case AF_INET:
|
|
/*
|
|
* IPv4 pseudo scoping according to RFC 3484.
|
|
*/
|
|
sa4 = (struct sockaddr_in *)sa;
|
|
/* IPv4 autoconfiguration addresses have link-local scope. */
|
|
if (((u_char *)&sa4->sin_addr)[0] == 169 &&
|
|
((u_char *)&sa4->sin_addr)[1] == 254)
|
|
return(2);
|
|
/* Private addresses have site-local scope. */
|
|
if (((u_char *)&sa4->sin_addr)[0] == 10 ||
|
|
(((u_char *)&sa4->sin_addr)[0] == 172 &&
|
|
(((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
|
|
(((u_char *)&sa4->sin_addr)[0] == 192 &&
|
|
((u_char *)&sa4->sin_addr)[1] == 168))
|
|
return(14); /* XXX: It should be 5 unless NAT */
|
|
/* Loopback addresses have link-local scope. */
|
|
if (((u_char *)&sa4->sin_addr)[0] == 127)
|
|
return(2);
|
|
return(14);
|
|
break;
|
|
default:
|
|
errno = EAFNOSUPPORT; /* is this a good error? */
|
|
return(-1);
|
|
}
|
|
}
|
|
|
|
static int
|
|
explore_copy(const struct addrinfo *pai, const struct addrinfo *src0,
|
|
struct addrinfo **res)
|
|
{
|
|
int error;
|
|
struct addrinfo sentinel, *cur;
|
|
const struct addrinfo *src;
|
|
|
|
error = 0;
|
|
sentinel.ai_next = NULL;
|
|
cur = &sentinel;
|
|
|
|
for (src = src0; src != NULL; src = src->ai_next) {
|
|
if (src->ai_family != pai->ai_family)
|
|
continue;
|
|
|
|
cur->ai_next = copy_ai(src);
|
|
if (!cur->ai_next) {
|
|
error = EAI_MEMORY;
|
|
goto fail;
|
|
}
|
|
|
|
cur->ai_next->ai_socktype = pai->ai_socktype;
|
|
cur->ai_next->ai_protocol = pai->ai_protocol;
|
|
cur = cur->ai_next;
|
|
}
|
|
|
|
*res = sentinel.ai_next;
|
|
return 0;
|
|
|
|
fail:
|
|
freeaddrinfo(sentinel.ai_next);
|
|
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 *ai;
|
|
int error;
|
|
|
|
*res = NULL;
|
|
ai = NULL;
|
|
|
|
/*
|
|
* filter out AFs that are not supported by the kernel
|
|
* XXX errno?
|
|
*/
|
|
s = _socket(pai->ai_family, SOCK_DGRAM, 0);
|
|
if (s < 0) {
|
|
if (errno != EMFILE)
|
|
return 0;
|
|
} else
|
|
_close(s);
|
|
|
|
afd = find_afd(pai->ai_family);
|
|
if (afd == NULL)
|
|
return 0;
|
|
|
|
if (pai->ai_flags & AI_PASSIVE) {
|
|
GET_AI(ai, afd, afd->a_addrany);
|
|
GET_PORT(ai, servname);
|
|
} else {
|
|
GET_AI(ai, afd, afd->a_loopback);
|
|
GET_PORT(ai, servname);
|
|
}
|
|
|
|
*res = ai;
|
|
return 0;
|
|
|
|
free:
|
|
if (ai != NULL)
|
|
freeaddrinfo(ai);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* numeric hostname
|
|
*/
|
|
static int
|
|
explore_numeric(const struct addrinfo *pai, const char *hostname,
|
|
const char *servname, struct addrinfo **res, const char *canonname)
|
|
{
|
|
const struct afd *afd;
|
|
struct addrinfo *ai;
|
|
int error;
|
|
char pton[PTON_MAX];
|
|
|
|
*res = NULL;
|
|
ai = NULL;
|
|
|
|
afd = find_afd(pai->ai_family);
|
|
if (afd == NULL)
|
|
return 0;
|
|
|
|
switch (afd->a_af) {
|
|
case AF_INET:
|
|
/*
|
|
* RFC3493 requires getaddrinfo() to accept AF_INET formats
|
|
* that are accepted by inet_addr() and its family. The
|
|
* accepted forms includes the "classful" one, which inet_pton
|
|
* does not accept. So we need to separate the case for
|
|
* AF_INET.
|
|
*/
|
|
if (inet_aton(hostname, (struct in_addr *)pton) != 1)
|
|
return 0;
|
|
break;
|
|
default:
|
|
if (inet_pton(afd->a_af, hostname, pton) != 1)
|
|
return 0;
|
|
break;
|
|
}
|
|
|
|
if (pai->ai_family == afd->a_af) {
|
|
GET_AI(ai, afd, pton);
|
|
GET_PORT(ai, servname);
|
|
if ((pai->ai_flags & AI_CANONNAME)) {
|
|
/*
|
|
* Set the numeric address itself as the canonical
|
|
* name, based on a clarification in RFC3493.
|
|
*/
|
|
GET_CANONNAME(ai, canonname);
|
|
}
|
|
} else {
|
|
/*
|
|
* XXX: This should not happen since we already matched the AF
|
|
* by find_afd.
|
|
*/
|
|
ERR(EAI_FAMILY);
|
|
}
|
|
|
|
*res = ai;
|
|
return 0;
|
|
|
|
free:
|
|
bad:
|
|
if (ai != NULL)
|
|
freeaddrinfo(ai);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* numeric hostname with scope
|
|
*/
|
|
static int
|
|
explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
|
|
const char *servname, struct addrinfo **res)
|
|
{
|
|
#if !defined(SCOPE_DELIMITER) || !defined(INET6)
|
|
return explore_numeric(pai, hostname, servname, res, hostname);
|
|
#else
|
|
const struct afd *afd;
|
|
struct addrinfo *cur;
|
|
int error;
|
|
char *cp, *hostname2 = NULL, *scope, *addr;
|
|
struct sockaddr_in6 *sin6;
|
|
|
|
afd = find_afd(pai->ai_family);
|
|
if (afd == NULL)
|
|
return 0;
|
|
|
|
if (!afd->a_scoped)
|
|
return explore_numeric(pai, hostname, servname, res, hostname);
|
|
|
|
cp = strchr(hostname, SCOPE_DELIMITER);
|
|
if (cp == NULL)
|
|
return explore_numeric(pai, hostname, servname, res, hostname);
|
|
|
|
/*
|
|
* Handle special case of <scoped_address><delimiter><scope id>
|
|
*/
|
|
hostname2 = strdup(hostname);
|
|
if (hostname2 == NULL)
|
|
return EAI_MEMORY;
|
|
/* terminate at the delimiter */
|
|
hostname2[cp - hostname] = '\0';
|
|
addr = hostname2;
|
|
scope = cp + 1;
|
|
|
|
error = explore_numeric(pai, addr, servname, res, hostname);
|
|
if (error == 0) {
|
|
u_int32_t scopeid;
|
|
|
|
for (cur = *res; cur; cur = cur->ai_next) {
|
|
if (cur->ai_family != AF_INET6)
|
|
continue;
|
|
sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
|
|
if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
|
|
free(hostname2);
|
|
freeaddrinfo(*res);
|
|
*res = NULL;
|
|
return(EAI_NONAME); /* XXX: is return OK? */
|
|
}
|
|
sin6->sin6_scope_id = scopeid;
|
|
}
|
|
}
|
|
|
|
free(hostname2);
|
|
|
|
if (error && *res) {
|
|
freeaddrinfo(*res);
|
|
*res = NULL;
|
|
}
|
|
return error;
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
|
|
{
|
|
if ((pai->ai_flags & AI_CANONNAME) != 0) {
|
|
ai->ai_canonname = strdup(str);
|
|
if (ai->ai_canonname == NULL)
|
|
return EAI_MEMORY;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct addrinfo *
|
|
get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
|
|
{
|
|
char *p;
|
|
struct addrinfo *ai;
|
|
#ifdef FAITH
|
|
struct in6_addr faith_prefix;
|
|
char *fp_str;
|
|
int translate = 0;
|
|
#endif
|
|
|
|
#ifdef FAITH
|
|
/*
|
|
* Transfrom an IPv4 addr into a special IPv6 addr format for
|
|
* IPv6->IPv4 translation gateway. (only TCP is supported now)
|
|
*
|
|
* +-----------------------------------+------------+
|
|
* | faith prefix part (12 bytes) | embedded |
|
|
* | | IPv4 addr part (4 bytes)
|
|
* +-----------------------------------+------------+
|
|
*
|
|
* faith prefix part is specified as ascii IPv6 addr format
|
|
* in environmental variable GAI.
|
|
* For FAITH to work correctly, routing to faith prefix must be
|
|
* setup toward a machine where a FAITH daemon operates.
|
|
* Also, the machine must enable some mechanizm
|
|
* (e.g. faith interface hack) to divert those packet with
|
|
* faith prefixed destination addr to user-land FAITH daemon.
|
|
*/
|
|
fp_str = getenv("GAI");
|
|
if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
|
|
afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
|
|
u_int32_t v4a;
|
|
u_int8_t v4a_top;
|
|
|
|
memcpy(&v4a, addr, sizeof v4a);
|
|
v4a_top = v4a >> IN_CLASSA_NSHIFT;
|
|
if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
|
|
v4a_top != 0 && v4a != IN_LOOPBACKNET) {
|
|
afd = &afdl[N_INET6];
|
|
memcpy(&faith_prefix.s6_addr[12], addr,
|
|
sizeof(struct in_addr));
|
|
translate = 1;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
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_addr->sa_len = 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);
|
|
#ifdef FAITH
|
|
if (translate == 1)
|
|
memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen);
|
|
else
|
|
#endif
|
|
memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
|
|
return ai;
|
|
}
|
|
|
|
/* XXX need to malloc() the same way we do from other functions! */
|
|
static struct addrinfo *
|
|
copy_ai(const struct addrinfo *pai)
|
|
{
|
|
struct addrinfo *ai;
|
|
size_t l;
|
|
|
|
l = sizeof(*ai) + pai->ai_addrlen;
|
|
if ((ai = (struct addrinfo *)malloc(l)) == NULL)
|
|
return NULL;
|
|
memset(ai, 0, l);
|
|
memcpy(ai, pai, sizeof(*ai));
|
|
ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
|
|
memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen);
|
|
|
|
if (pai->ai_canonname) {
|
|
l = strlen(pai->ai_canonname) + 1;
|
|
if ((ai->ai_canonname = malloc(l)) == NULL) {
|
|
free(ai);
|
|
return NULL;
|
|
}
|
|
strlcpy(ai->ai_canonname, pai->ai_canonname, l);
|
|
} else {
|
|
/* just to make sure */
|
|
ai->ai_canonname = NULL;
|
|
}
|
|
|
|
ai->ai_next = NULL;
|
|
|
|
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, error;
|
|
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:
|
|
case SOCK_SEQPACKET:
|
|
allownumeric = 1;
|
|
break;
|
|
case ANY:
|
|
switch (ai->ai_family) {
|
|
case AF_INET:
|
|
#ifdef AF_INET6
|
|
case AF_INET6:
|
|
#endif
|
|
allownumeric = 1;
|
|
break;
|
|
default:
|
|
allownumeric = 0;
|
|
break;
|
|
}
|
|
break;
|
|
default:
|
|
return EAI_SOCKTYPE;
|
|
}
|
|
|
|
error = str2number(servname, &port);
|
|
if (error == 0) {
|
|
if (!allownumeric)
|
|
return EAI_SERVICE;
|
|
if (port < 0 || port > 65535)
|
|
return EAI_SERVICE;
|
|
port = htons(port);
|
|
} else {
|
|
if (ai->ai_flags & AI_NUMERICSERV)
|
|
return EAI_NONAME;
|
|
|
|
switch (ai->ai_protocol) {
|
|
case IPPROTO_UDP:
|
|
proto = "udp";
|
|
break;
|
|
case IPPROTO_TCP:
|
|
proto = "tcp";
|
|
break;
|
|
case IPPROTO_SCTP:
|
|
proto = "sctp";
|
|
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 INET6
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
|
|
* will take care of it.
|
|
* the semantics of AI_ADDRCONFIG is not defined well. we are not sure
|
|
* if the code is right or not.
|
|
*
|
|
* XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
|
|
* _dns_getaddrinfo.
|
|
*/
|
|
static int
|
|
addrconfig(struct addrinfo *pai)
|
|
{
|
|
int s, af;
|
|
|
|
/*
|
|
* TODO:
|
|
* Note that implementation dependent test for address
|
|
* configuration should be done everytime called
|
|
* (or apropriate interval),
|
|
* because addresses will be dynamically assigned or deleted.
|
|
*/
|
|
af = pai->ai_family;
|
|
if (af == AF_UNSPEC) {
|
|
if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
|
|
af = AF_INET;
|
|
else {
|
|
_close(s);
|
|
if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0)
|
|
af = AF_INET6;
|
|
else
|
|
_close(s);
|
|
}
|
|
}
|
|
if (af != AF_UNSPEC) {
|
|
if ((s = _socket(af, SOCK_DGRAM, 0)) < 0)
|
|
return 0;
|
|
_close(s);
|
|
}
|
|
pai->ai_family = af;
|
|
return 1;
|
|
}
|
|
|
|
#ifdef INET6
|
|
/* convert a string to a scope identifier. XXX: IPv6 specific */
|
|
static int
|
|
ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
|
|
{
|
|
u_long lscopeid;
|
|
struct in6_addr *a6;
|
|
char *ep;
|
|
|
|
a6 = &sin6->sin6_addr;
|
|
|
|
/* empty scopeid portion is invalid */
|
|
if (*scope == '\0')
|
|
return -1;
|
|
|
|
if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) ||
|
|
IN6_IS_ADDR_MC_NODELOCAL(a6)) {
|
|
/*
|
|
* We currently assume a one-to-one mapping between links
|
|
* and interfaces, so we simply use interface indices for
|
|
* like-local scopes.
|
|
*/
|
|
*scopeid = if_nametoindex(scope);
|
|
if (*scopeid == 0)
|
|
goto trynumeric;
|
|
return 0;
|
|
}
|
|
|
|
/* still unclear about literal, allow numeric only - placeholder */
|
|
if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
|
|
goto trynumeric;
|
|
if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
|
|
goto trynumeric;
|
|
else
|
|
goto trynumeric; /* global */
|
|
|
|
/* try to convert to a numeric id as a last resort */
|
|
trynumeric:
|
|
errno = 0;
|
|
lscopeid = strtoul(scope, &ep, 10);
|
|
*scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
|
|
if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
|
|
return 0;
|
|
else
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
|
|
#ifdef NS_CACHING
|
|
static int
|
|
addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap,
|
|
void *cache_mdata)
|
|
{
|
|
res_state statp;
|
|
u_long res_options;
|
|
|
|
const int op_id = 0; /* identifies the getaddrinfo for the cache */
|
|
char *hostname;
|
|
struct addrinfo *hints;
|
|
|
|
char *p;
|
|
int ai_flags, ai_family, ai_socktype, ai_protocol;
|
|
size_t desired_size, size;
|
|
|
|
statp = __res_state();
|
|
res_options = statp->options & (RES_RECURSE | RES_DEFNAMES |
|
|
RES_DNSRCH | RES_NOALIASES | RES_USE_INET6);
|
|
|
|
hostname = va_arg(ap, char *);
|
|
hints = va_arg(ap, struct addrinfo *);
|
|
|
|
desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4;
|
|
if (hostname != NULL) {
|
|
size = strlen(hostname);
|
|
desired_size += size + 1;
|
|
} else
|
|
size = 0;
|
|
|
|
if (desired_size > *buffer_size) {
|
|
*buffer_size = desired_size;
|
|
return (NS_RETURN);
|
|
}
|
|
|
|
if (hints == NULL)
|
|
ai_flags = ai_family = ai_socktype = ai_protocol = 0;
|
|
else {
|
|
ai_flags = hints->ai_flags;
|
|
ai_family = hints->ai_family;
|
|
ai_socktype = hints->ai_socktype;
|
|
ai_protocol = hints->ai_protocol;
|
|
}
|
|
|
|
p = buffer;
|
|
memcpy(p, &res_options, sizeof(res_options));
|
|
p += sizeof(res_options);
|
|
|
|
memcpy(p, &op_id, sizeof(int));
|
|
p += sizeof(int);
|
|
|
|
memcpy(p, &ai_flags, sizeof(int));
|
|
p += sizeof(int);
|
|
|
|
memcpy(p, &ai_family, sizeof(int));
|
|
p += sizeof(int);
|
|
|
|
memcpy(p, &ai_socktype, sizeof(int));
|
|
p += sizeof(int);
|
|
|
|
memcpy(p, &ai_protocol, sizeof(int));
|
|
p += sizeof(int);
|
|
|
|
if (hostname != NULL)
|
|
memcpy(p, hostname, size);
|
|
|
|
*buffer_size = desired_size;
|
|
return (NS_SUCCESS);
|
|
}
|
|
|
|
static int
|
|
addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval,
|
|
va_list ap, void *cache_mdata)
|
|
{
|
|
struct addrinfo *ai, *cai;
|
|
char *p;
|
|
size_t desired_size, size, ai_size;
|
|
|
|
ai = *((struct addrinfo **)retval);
|
|
|
|
desired_size = sizeof(size_t);
|
|
ai_size = 0;
|
|
for (cai = ai; cai != NULL; cai = cai->ai_next) {
|
|
desired_size += sizeof(struct addrinfo) + cai->ai_addrlen;
|
|
if (cai->ai_canonname != NULL)
|
|
desired_size += sizeof(size_t) +
|
|
strlen(cai->ai_canonname);
|
|
++ai_size;
|
|
}
|
|
|
|
if (desired_size > *buffer_size) {
|
|
/* this assignment is here for future use */
|
|
errno = ERANGE;
|
|
*buffer_size = desired_size;
|
|
return (NS_RETURN);
|
|
}
|
|
|
|
memset(buffer, 0, desired_size);
|
|
p = buffer;
|
|
|
|
memcpy(p, &ai_size, sizeof(size_t));
|
|
p += sizeof(size_t);
|
|
for (cai = ai; cai != NULL; cai = cai->ai_next) {
|
|
memcpy(p, cai, sizeof(struct addrinfo));
|
|
p += sizeof(struct addrinfo);
|
|
|
|
memcpy(p, cai->ai_addr, cai->ai_addrlen);
|
|
p += cai->ai_addrlen;
|
|
|
|
if (cai->ai_canonname != NULL) {
|
|
size = strlen(cai->ai_canonname);
|
|
memcpy(p, &size, sizeof(size_t));
|
|
p += sizeof(size_t);
|
|
|
|
memcpy(p, cai->ai_canonname, size);
|
|
p += size;
|
|
}
|
|
}
|
|
|
|
return (NS_SUCCESS);
|
|
}
|
|
|
|
static int
|
|
addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval,
|
|
va_list ap, void *cache_mdata)
|
|
{
|
|
struct addrinfo new_ai, *result, *sentinel, *lasts;
|
|
|
|
char *p;
|
|
size_t ai_size, ai_i, size;
|
|
|
|
p = buffer;
|
|
memcpy(&ai_size, p, sizeof(size_t));
|
|
p += sizeof(size_t);
|
|
|
|
result = NULL;
|
|
lasts = NULL;
|
|
for (ai_i = 0; ai_i < ai_size; ++ai_i) {
|
|
memcpy(&new_ai, p, sizeof(struct addrinfo));
|
|
p += sizeof(struct addrinfo);
|
|
size = new_ai.ai_addrlen + sizeof(struct addrinfo) +
|
|
_ALIGNBYTES;
|
|
|
|
sentinel = (struct addrinfo *)malloc(size);
|
|
memset(sentinel, 0, size);
|
|
|
|
memcpy(sentinel, &new_ai, sizeof(struct addrinfo));
|
|
sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel +
|
|
sizeof(struct addrinfo));
|
|
|
|
memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen);
|
|
p += new_ai.ai_addrlen;
|
|
|
|
if (new_ai.ai_canonname != NULL) {
|
|
memcpy(&size, p, sizeof(size_t));
|
|
p += sizeof(size_t);
|
|
|
|
sentinel->ai_canonname = (char *)malloc(size + 1);
|
|
memset(sentinel->ai_canonname, 0, size + 1);
|
|
|
|
memcpy(sentinel->ai_canonname, p, size);
|
|
p += size;
|
|
}
|
|
|
|
if (result == NULL) {
|
|
result = sentinel;
|
|
lasts = sentinel;
|
|
} else {
|
|
lasts->ai_next = sentinel;
|
|
lasts = sentinel;
|
|
}
|
|
}
|
|
|
|
*((struct addrinfo **)retval) = result;
|
|
return (NS_SUCCESS);
|
|
}
|
|
#endif /* NS_CACHING */
|
|
|
|
/*
|
|
* FQDN hostname, DNS lookup
|
|
*/
|
|
static int
|
|
explore_fqdn(const struct addrinfo *pai, const char *hostname,
|
|
const char *servname, struct addrinfo **res)
|
|
{
|
|
struct addrinfo *result;
|
|
struct addrinfo *cur;
|
|
int error = 0;
|
|
|
|
#ifdef NS_CACHING
|
|
static const nss_cache_info cache_info =
|
|
NS_COMMON_CACHE_INFO_INITIALIZER(
|
|
hosts, NULL, addrinfo_id_func, addrinfo_marshal_func,
|
|
addrinfo_unmarshal_func);
|
|
#endif
|
|
static const ns_dtab dtab[] = {
|
|
NS_FILES_CB(_files_getaddrinfo, NULL)
|
|
{ NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */
|
|
NS_NIS_CB(_yp_getaddrinfo, NULL)
|
|
#ifdef NS_CACHING
|
|
NS_CACHE_CB(&cache_info)
|
|
#endif
|
|
{ 0 }
|
|
};
|
|
|
|
result = NULL;
|
|
|
|
/*
|
|
* if the servname does not match socktype/protocol, ignore it.
|
|
*/
|
|
if (get_portmatch(pai, servname) != 0)
|
|
return 0;
|
|
|
|
switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
|
|
default_dns_files, hostname, pai)) {
|
|
case NS_TRYAGAIN:
|
|
error = EAI_AGAIN;
|
|
goto free;
|
|
case NS_UNAVAIL:
|
|
error = EAI_FAIL;
|
|
goto free;
|
|
case NS_NOTFOUND:
|
|
error = EAI_NONAME;
|
|
goto free;
|
|
case NS_SUCCESS:
|
|
error = 0;
|
|
for (cur = result; cur; cur = cur->ai_next) {
|
|
GET_PORT(cur, servname);
|
|
/* canonname should be filled already */
|
|
}
|
|
break;
|
|
}
|
|
|
|
*res = result;
|
|
|
|
return 0;
|
|
|
|
free:
|
|
if (result)
|
|
freeaddrinfo(result);
|
|
return error;
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
static const char AskedForGot[] =
|
|
"gethostby*.getanswer: asked for \"%s\", got \"%s\"";
|
|
#endif
|
|
|
|
static struct addrinfo *
|
|
getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
|
|
const struct addrinfo *pai, res_state res)
|
|
{
|
|
struct addrinfo sentinel, *cur;
|
|
struct addrinfo ai;
|
|
const struct afd *afd;
|
|
char *canonname;
|
|
const HEADER *hp;
|
|
const u_char *cp;
|
|
int n;
|
|
const u_char *eom;
|
|
char *bp, *ep;
|
|
int type, class, ancount, qdcount;
|
|
int haveanswer, had_error;
|
|
char tbuf[MAXDNAME];
|
|
int (*name_ok)(const char *);
|
|
char hostbuf[8*1024];
|
|
|
|
memset(&sentinel, 0, sizeof(sentinel));
|
|
cur = &sentinel;
|
|
|
|
canonname = NULL;
|
|
eom = answer->buf + anslen;
|
|
switch (qtype) {
|
|
case T_A:
|
|
case T_AAAA:
|
|
case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
|
|
name_ok = res_hnok;
|
|
break;
|
|
default:
|
|
return (NULL); /* XXX should be abort(); */
|
|
}
|
|
/*
|
|
* find first satisfactory answer
|
|
*/
|
|
hp = &answer->hdr;
|
|
ancount = ntohs(hp->ancount);
|
|
qdcount = ntohs(hp->qdcount);
|
|
bp = hostbuf;
|
|
ep = hostbuf + sizeof hostbuf;
|
|
cp = answer->buf + HFIXEDSZ;
|
|
if (qdcount != 1) {
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (NULL);
|
|
}
|
|
n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
|
|
if ((n < 0) || !(*name_ok)(bp)) {
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (NULL);
|
|
}
|
|
cp += n + QFIXEDSZ;
|
|
if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
|
|
/* res_send() has already verified that the query name is the
|
|
* same as the one we sent; this just gets the expanded name
|
|
* (i.e., with the succeeding search-domain tacked on).
|
|
*/
|
|
n = strlen(bp) + 1; /* for the \0 */
|
|
if (n >= MAXHOSTNAMELEN) {
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (NULL);
|
|
}
|
|
canonname = bp;
|
|
bp += n;
|
|
/* The qname can be abbreviated, but h_name is now absolute. */
|
|
qname = canonname;
|
|
}
|
|
haveanswer = 0;
|
|
had_error = 0;
|
|
while (ancount-- > 0 && cp < eom && !had_error) {
|
|
n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
|
|
if ((n < 0) || !(*name_ok)(bp)) {
|
|
had_error++;
|
|
continue;
|
|
}
|
|
cp += n; /* name */
|
|
type = _getshort(cp);
|
|
cp += INT16SZ; /* type */
|
|
class = _getshort(cp);
|
|
cp += INT16SZ + INT32SZ; /* class, TTL */
|
|
n = _getshort(cp);
|
|
cp += INT16SZ; /* len */
|
|
if (class != C_IN) {
|
|
/* XXX - debug? syslog? */
|
|
cp += n;
|
|
continue; /* XXX - had_error++ ? */
|
|
}
|
|
if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
|
|
type == T_CNAME) {
|
|
n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
|
|
if ((n < 0) || !(*name_ok)(tbuf)) {
|
|
had_error++;
|
|
continue;
|
|
}
|
|
cp += n;
|
|
/* Get canonical name. */
|
|
n = strlen(tbuf) + 1; /* for the \0 */
|
|
if (n > ep - bp || n >= MAXHOSTNAMELEN) {
|
|
had_error++;
|
|
continue;
|
|
}
|
|
strlcpy(bp, tbuf, ep - bp);
|
|
canonname = bp;
|
|
bp += n;
|
|
continue;
|
|
}
|
|
if (qtype == T_ANY) {
|
|
if (!(type == T_A || type == T_AAAA)) {
|
|
cp += n;
|
|
continue;
|
|
}
|
|
} else if (type != qtype) {
|
|
#ifdef DEBUG
|
|
if (type != T_KEY && type != T_SIG &&
|
|
type != ns_t_dname)
|
|
syslog(LOG_NOTICE|LOG_AUTH,
|
|
"gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
|
|
qname, p_class(C_IN), p_type(qtype),
|
|
p_type(type));
|
|
#endif
|
|
cp += n;
|
|
continue; /* XXX - had_error++ ? */
|
|
}
|
|
switch (type) {
|
|
case T_A:
|
|
case T_AAAA:
|
|
if (strcasecmp(canonname, bp) != 0) {
|
|
#ifdef DEBUG
|
|
syslog(LOG_NOTICE|LOG_AUTH,
|
|
AskedForGot, canonname, bp);
|
|
#endif
|
|
cp += n;
|
|
continue; /* XXX - had_error++ ? */
|
|
}
|
|
if (type == T_A && n != INADDRSZ) {
|
|
cp += n;
|
|
continue;
|
|
}
|
|
if (type == T_AAAA && n != IN6ADDRSZ) {
|
|
cp += n;
|
|
continue;
|
|
}
|
|
#ifdef FILTER_V4MAPPED
|
|
if (type == T_AAAA) {
|
|
struct in6_addr in6;
|
|
memcpy(&in6, cp, sizeof(in6));
|
|
if (IN6_IS_ADDR_V4MAPPED(&in6)) {
|
|
cp += n;
|
|
continue;
|
|
}
|
|
}
|
|
#endif
|
|
if (!haveanswer) {
|
|
int nn;
|
|
|
|
canonname = bp;
|
|
nn = strlen(bp) + 1; /* for the \0 */
|
|
bp += nn;
|
|
}
|
|
|
|
/* don't overwrite pai */
|
|
ai = *pai;
|
|
ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
|
|
afd = find_afd(ai.ai_family);
|
|
if (afd == NULL) {
|
|
cp += n;
|
|
continue;
|
|
}
|
|
cur->ai_next = get_ai(&ai, afd, (const char *)cp);
|
|
if (cur->ai_next == NULL)
|
|
had_error++;
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
cp += n;
|
|
break;
|
|
default:
|
|
abort();
|
|
}
|
|
if (!had_error)
|
|
haveanswer++;
|
|
}
|
|
if (haveanswer) {
|
|
#if defined(RESOLVSORT)
|
|
/*
|
|
* We support only IPv4 address for backward
|
|
* compatibility against gethostbyname(3).
|
|
*/
|
|
if (res->nsort && qtype == T_A) {
|
|
if (addr4sort(&sentinel, res) < 0) {
|
|
freeaddrinfo(sentinel.ai_next);
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return NULL;
|
|
}
|
|
}
|
|
#endif /*RESOLVSORT*/
|
|
if (!canonname)
|
|
(void)get_canonname(pai, sentinel.ai_next, qname);
|
|
else
|
|
(void)get_canonname(pai, sentinel.ai_next, canonname);
|
|
RES_SET_H_ERRNO(res, NETDB_SUCCESS);
|
|
return sentinel.ai_next;
|
|
}
|
|
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef RESOLVSORT
|
|
struct addr_ptr {
|
|
struct addrinfo *ai;
|
|
int aval;
|
|
};
|
|
|
|
static int
|
|
addr4sort(struct addrinfo *sentinel, res_state res)
|
|
{
|
|
struct addrinfo *ai;
|
|
struct addr_ptr *addrs, addr;
|
|
struct sockaddr_in *sin;
|
|
int naddrs, i, j;
|
|
int needsort = 0;
|
|
|
|
if (!sentinel)
|
|
return -1;
|
|
naddrs = 0;
|
|
for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
|
|
naddrs++;
|
|
if (naddrs < 2)
|
|
return 0; /* We don't need sorting. */
|
|
if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
|
|
return -1;
|
|
i = 0;
|
|
for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
|
|
sin = (struct sockaddr_in *)ai->ai_addr;
|
|
for (j = 0; (unsigned)j < res->nsort; j++) {
|
|
if (res->sort_list[j].addr.s_addr ==
|
|
(sin->sin_addr.s_addr & res->sort_list[j].mask))
|
|
break;
|
|
}
|
|
addrs[i].ai = ai;
|
|
addrs[i].aval = j;
|
|
if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
|
|
needsort = i;
|
|
i++;
|
|
}
|
|
if (!needsort) {
|
|
free(addrs);
|
|
return 0;
|
|
}
|
|
|
|
while (needsort < naddrs) {
|
|
for (j = needsort - 1; j >= 0; j--) {
|
|
if (addrs[j].aval > addrs[j+1].aval) {
|
|
addr = addrs[j];
|
|
addrs[j] = addrs[j + 1];
|
|
addrs[j + 1] = addr;
|
|
} else
|
|
break;
|
|
}
|
|
needsort++;
|
|
}
|
|
|
|
ai = sentinel;
|
|
for (i = 0; i < naddrs; ++i) {
|
|
ai->ai_next = addrs[i].ai;
|
|
ai = ai->ai_next;
|
|
}
|
|
ai->ai_next = NULL;
|
|
free(addrs);
|
|
return 0;
|
|
}
|
|
#endif /*RESOLVSORT*/
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
_dns_getaddrinfo(void *rv, void *cb_data, va_list ap)
|
|
{
|
|
struct addrinfo *ai;
|
|
querybuf *buf, *buf2;
|
|
const char *hostname;
|
|
const struct addrinfo *pai;
|
|
struct addrinfo sentinel, *cur;
|
|
struct res_target q, q2;
|
|
res_state res;
|
|
|
|
hostname = va_arg(ap, char *);
|
|
pai = va_arg(ap, const struct addrinfo *);
|
|
|
|
memset(&q, 0, sizeof(q));
|
|
memset(&q2, 0, sizeof(q2));
|
|
memset(&sentinel, 0, sizeof(sentinel));
|
|
cur = &sentinel;
|
|
|
|
buf = malloc(sizeof(*buf));
|
|
if (!buf) {
|
|
RES_SET_H_ERRNO(res, NETDB_INTERNAL);
|
|
return NS_NOTFOUND;
|
|
}
|
|
buf2 = malloc(sizeof(*buf2));
|
|
if (!buf2) {
|
|
free(buf);
|
|
RES_SET_H_ERRNO(res, NETDB_INTERNAL);
|
|
return NS_NOTFOUND;
|
|
}
|
|
|
|
switch (pai->ai_family) {
|
|
case AF_UNSPEC:
|
|
q.name = hostname;
|
|
q.qclass = C_IN;
|
|
q.qtype = T_A;
|
|
q.answer = buf->buf;
|
|
q.anslen = sizeof(buf->buf);
|
|
q.next = &q2;
|
|
q2.name = hostname;
|
|
q2.qclass = C_IN;
|
|
q2.qtype = T_AAAA;
|
|
q2.answer = buf2->buf;
|
|
q2.anslen = sizeof(buf2->buf);
|
|
break;
|
|
case AF_INET:
|
|
q.name = hostname;
|
|
q.qclass = C_IN;
|
|
q.qtype = T_A;
|
|
q.answer = buf->buf;
|
|
q.anslen = sizeof(buf->buf);
|
|
break;
|
|
case AF_INET6:
|
|
q.name = hostname;
|
|
q.qclass = C_IN;
|
|
q.qtype = T_AAAA;
|
|
q.answer = buf->buf;
|
|
q.anslen = sizeof(buf->buf);
|
|
break;
|
|
default:
|
|
free(buf);
|
|
free(buf2);
|
|
return NS_UNAVAIL;
|
|
}
|
|
|
|
res = __res_state();
|
|
if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) {
|
|
RES_SET_H_ERRNO(res, NETDB_INTERNAL);
|
|
free(buf);
|
|
free(buf2);
|
|
return NS_NOTFOUND;
|
|
}
|
|
|
|
if (res_searchN(hostname, &q, res) < 0) {
|
|
free(buf);
|
|
free(buf2);
|
|
return NS_NOTFOUND;
|
|
}
|
|
/* prefer IPv6 */
|
|
if (q.next) {
|
|
ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res);
|
|
if (ai) {
|
|
cur->ai_next = ai;
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
}
|
|
}
|
|
ai = getanswer(buf, q.n, q.name, q.qtype, pai, res);
|
|
if (ai)
|
|
cur->ai_next = ai;
|
|
free(buf);
|
|
free(buf2);
|
|
if (sentinel.ai_next == NULL)
|
|
switch (res->res_h_errno) {
|
|
case HOST_NOT_FOUND:
|
|
return NS_NOTFOUND;
|
|
case TRY_AGAIN:
|
|
return NS_TRYAGAIN;
|
|
default:
|
|
return NS_UNAVAIL;
|
|
}
|
|
*((struct addrinfo **)rv) = sentinel.ai_next;
|
|
return NS_SUCCESS;
|
|
}
|
|
|
|
static void
|
|
_sethtent(FILE **hostf)
|
|
{
|
|
if (!*hostf)
|
|
*hostf = fopen(_PATH_HOSTS, "r");
|
|
else
|
|
rewind(*hostf);
|
|
}
|
|
|
|
static void
|
|
_endhtent(FILE **hostf)
|
|
{
|
|
if (*hostf) {
|
|
(void) fclose(*hostf);
|
|
*hostf = NULL;
|
|
}
|
|
}
|
|
|
|
static struct addrinfo *
|
|
_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
|
|
{
|
|
char *p;
|
|
char *cp, *tname, *cname;
|
|
struct addrinfo hints, *res0, *res;
|
|
int error;
|
|
const char *addr;
|
|
char hostbuf[8*1024];
|
|
|
|
if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r")))
|
|
return (NULL);
|
|
again:
|
|
if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf)))
|
|
return (NULL);
|
|
if (*p == '#')
|
|
goto again;
|
|
cp = strpbrk(p, "#\n");
|
|
if (cp != NULL)
|
|
*cp = '\0';
|
|
if (!(cp = strpbrk(p, " \t")))
|
|
goto again;
|
|
*cp++ = '\0';
|
|
addr = p;
|
|
cname = NULL;
|
|
/* if this is not something we're looking for, skip it. */
|
|
while (cp && *cp) {
|
|
if (*cp == ' ' || *cp == '\t') {
|
|
cp++;
|
|
continue;
|
|
}
|
|
tname = cp;
|
|
if (cname == NULL)
|
|
cname = cp;
|
|
if ((cp = strpbrk(cp, " \t")) != NULL)
|
|
*cp++ = '\0';
|
|
if (strcasecmp(name, tname) == 0)
|
|
goto found;
|
|
}
|
|
goto again;
|
|
|
|
found:
|
|
/* we should not glob socktype/protocol here */
|
|
memset(&hints, 0, sizeof(hints));
|
|
hints.ai_family = pai->ai_family;
|
|
hints.ai_socktype = SOCK_DGRAM;
|
|
hints.ai_protocol = 0;
|
|
hints.ai_flags = AI_NUMERICHOST;
|
|
error = getaddrinfo(addr, "0", &hints, &res0);
|
|
if (error)
|
|
goto again;
|
|
#ifdef FILTER_V4MAPPED
|
|
/* XXX should check all items in the chain */
|
|
if (res0->ai_family == AF_INET6 &&
|
|
IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
|
|
freeaddrinfo(res0);
|
|
goto again;
|
|
}
|
|
#endif
|
|
for (res = res0; res; res = res->ai_next) {
|
|
/* cover it up */
|
|
res->ai_flags = pai->ai_flags;
|
|
res->ai_socktype = pai->ai_socktype;
|
|
res->ai_protocol = pai->ai_protocol;
|
|
|
|
if (pai->ai_flags & AI_CANONNAME) {
|
|
if (get_canonname(pai, res, cname) != 0) {
|
|
freeaddrinfo(res0);
|
|
goto again;
|
|
}
|
|
}
|
|
}
|
|
return res0;
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
_files_getaddrinfo(void *rv, void *cb_data, va_list ap)
|
|
{
|
|
const char *name;
|
|
const struct addrinfo *pai;
|
|
struct addrinfo sentinel, *cur;
|
|
struct addrinfo *p;
|
|
FILE *hostf = NULL;
|
|
|
|
name = va_arg(ap, char *);
|
|
pai = va_arg(ap, struct addrinfo *);
|
|
|
|
memset(&sentinel, 0, sizeof(sentinel));
|
|
cur = &sentinel;
|
|
|
|
_sethtent(&hostf);
|
|
while ((p = _gethtent(&hostf, name, pai)) != NULL) {
|
|
cur->ai_next = p;
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
}
|
|
_endhtent(&hostf);
|
|
|
|
*((struct addrinfo **)rv) = sentinel.ai_next;
|
|
if (sentinel.ai_next == NULL)
|
|
return NS_NOTFOUND;
|
|
return NS_SUCCESS;
|
|
}
|
|
|
|
#ifdef YP
|
|
/*ARGSUSED*/
|
|
static struct addrinfo *
|
|
_yphostent(char *line, const struct addrinfo *pai)
|
|
{
|
|
struct addrinfo sentinel, *cur;
|
|
struct addrinfo hints, *res, *res0;
|
|
int error;
|
|
char *p = line;
|
|
const char *addr, *canonname;
|
|
char *nextline;
|
|
char *cp;
|
|
|
|
addr = canonname = NULL;
|
|
|
|
memset(&sentinel, 0, sizeof(sentinel));
|
|
cur = &sentinel;
|
|
|
|
nextline:
|
|
/* terminate line */
|
|
cp = strchr(p, '\n');
|
|
if (cp) {
|
|
*cp++ = '\0';
|
|
nextline = cp;
|
|
} else
|
|
nextline = NULL;
|
|
|
|
cp = strpbrk(p, " \t");
|
|
if (cp == NULL) {
|
|
if (canonname == NULL)
|
|
return (NULL);
|
|
else
|
|
goto done;
|
|
}
|
|
*cp++ = '\0';
|
|
|
|
addr = p;
|
|
|
|
while (cp && *cp) {
|
|
if (*cp == ' ' || *cp == '\t') {
|
|
cp++;
|
|
continue;
|
|
}
|
|
if (!canonname)
|
|
canonname = cp;
|
|
if ((cp = strpbrk(cp, " \t")) != NULL)
|
|
*cp++ = '\0';
|
|
}
|
|
|
|
hints = *pai;
|
|
hints.ai_flags = AI_NUMERICHOST;
|
|
error = getaddrinfo(addr, NULL, &hints, &res0);
|
|
if (error == 0) {
|
|
for (res = res0; res; res = res->ai_next) {
|
|
/* cover it up */
|
|
res->ai_flags = pai->ai_flags;
|
|
|
|
if (pai->ai_flags & AI_CANONNAME)
|
|
(void)get_canonname(pai, res, canonname);
|
|
}
|
|
} else
|
|
res0 = NULL;
|
|
if (res0) {
|
|
cur->ai_next = res0;
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
}
|
|
|
|
if (nextline) {
|
|
p = nextline;
|
|
goto nextline;
|
|
}
|
|
|
|
done:
|
|
return sentinel.ai_next;
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
_yp_getaddrinfo(void *rv, void *cb_data, va_list ap)
|
|
{
|
|
struct addrinfo sentinel, *cur;
|
|
struct addrinfo *ai = NULL;
|
|
char *ypbuf;
|
|
int ypbuflen, r;
|
|
const char *name;
|
|
const struct addrinfo *pai;
|
|
char *ypdomain;
|
|
|
|
if (_yp_check(&ypdomain) == 0)
|
|
return NS_UNAVAIL;
|
|
|
|
name = va_arg(ap, char *);
|
|
pai = va_arg(ap, const struct addrinfo *);
|
|
|
|
memset(&sentinel, 0, sizeof(sentinel));
|
|
cur = &sentinel;
|
|
|
|
/* hosts.byname is only for IPv4 (Solaris8) */
|
|
if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
|
|
r = yp_match(ypdomain, "hosts.byname", name,
|
|
(int)strlen(name), &ypbuf, &ypbuflen);
|
|
if (r == 0) {
|
|
struct addrinfo ai4;
|
|
|
|
ai4 = *pai;
|
|
ai4.ai_family = AF_INET;
|
|
ai = _yphostent(ypbuf, &ai4);
|
|
if (ai) {
|
|
cur->ai_next = ai;
|
|
while (cur && cur->ai_next)
|
|
cur = cur->ai_next;
|
|
}
|
|
free(ypbuf);
|
|
}
|
|
}
|
|
|
|
/* ipnodes.byname can hold both IPv4/v6 */
|
|
r = yp_match(ypdomain, "ipnodes.byname", name,
|
|
(int)strlen(name), &ypbuf, &ypbuflen);
|
|
if (r == 0) {
|
|
ai = _yphostent(ypbuf, pai);
|
|
if (ai)
|
|
cur->ai_next = ai;
|
|
free(ypbuf);
|
|
}
|
|
|
|
if (sentinel.ai_next == NULL) {
|
|
RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND);
|
|
return NS_NOTFOUND;
|
|
}
|
|
*((struct addrinfo **)rv) = sentinel.ai_next;
|
|
return NS_SUCCESS;
|
|
}
|
|
#endif
|
|
|
|
/* resolver logic */
|
|
|
|
/*
|
|
* Formulate a normal query, send, and await answer.
|
|
* Returned answer is placed in supplied buffer "answer".
|
|
* Perform preliminary check of answer, returning success only
|
|
* if no error is indicated and the answer count is nonzero.
|
|
* Return the size of the response on success, -1 on error.
|
|
* Error number is left in h_errno.
|
|
*
|
|
* Caller must parse answer and determine whether it answers the question.
|
|
*/
|
|
static int
|
|
res_queryN(const char *name, struct res_target *target, res_state res)
|
|
{
|
|
u_char *buf;
|
|
HEADER *hp;
|
|
int n;
|
|
u_int oflags;
|
|
struct res_target *t;
|
|
int rcode;
|
|
int ancount;
|
|
|
|
rcode = NOERROR;
|
|
ancount = 0;
|
|
|
|
buf = malloc(MAXPACKET);
|
|
if (!buf) {
|
|
RES_SET_H_ERRNO(res, NETDB_INTERNAL);
|
|
return -1;
|
|
}
|
|
|
|
for (t = target; t; t = t->next) {
|
|
int class, type;
|
|
u_char *answer;
|
|
int anslen;
|
|
|
|
hp = (HEADER *)(void *)t->answer;
|
|
|
|
/* make it easier... */
|
|
class = t->qclass;
|
|
type = t->qtype;
|
|
answer = t->answer;
|
|
anslen = t->anslen;
|
|
|
|
oflags = res->_flags;
|
|
|
|
again:
|
|
hp->rcode = NOERROR; /* default */
|
|
|
|
#ifdef DEBUG
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; res_query(%s, %d, %d)\n", name, class, type);
|
|
#endif
|
|
|
|
n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL,
|
|
buf, MAXPACKET);
|
|
if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 &&
|
|
(res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U)
|
|
n = res_nopt(res, n, buf, MAXPACKET, anslen);
|
|
if (n <= 0) {
|
|
#ifdef DEBUG
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; res_query: mkquery failed\n");
|
|
#endif
|
|
free(buf);
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (n);
|
|
}
|
|
n = res_nsend(res, buf, n, answer, anslen);
|
|
if (n < 0) {
|
|
/*
|
|
* if the query choked with EDNS0, retry
|
|
* without EDNS0
|
|
*/
|
|
if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC))
|
|
!= 0U &&
|
|
((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) {
|
|
res->_flags |= RES_F_EDNS0ERR;
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; res_nquery: retry without EDNS0\n");
|
|
goto again;
|
|
}
|
|
rcode = hp->rcode; /* record most recent error */
|
|
#ifdef DEBUG
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; res_query: send error\n");
|
|
#endif
|
|
continue;
|
|
}
|
|
|
|
if (n > anslen)
|
|
hp->rcode = FORMERR; /* XXX not very informative */
|
|
if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
|
|
rcode = hp->rcode; /* record most recent error */
|
|
#ifdef DEBUG
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; rcode = %u, ancount=%u\n", hp->rcode,
|
|
ntohs(hp->ancount));
|
|
#endif
|
|
continue;
|
|
}
|
|
|
|
ancount += ntohs(hp->ancount);
|
|
|
|
t->n = n;
|
|
}
|
|
|
|
free(buf);
|
|
|
|
if (ancount == 0) {
|
|
switch (rcode) {
|
|
case NXDOMAIN:
|
|
RES_SET_H_ERRNO(res, HOST_NOT_FOUND);
|
|
break;
|
|
case SERVFAIL:
|
|
RES_SET_H_ERRNO(res, TRY_AGAIN);
|
|
break;
|
|
case NOERROR:
|
|
RES_SET_H_ERRNO(res, NO_DATA);
|
|
break;
|
|
case FORMERR:
|
|
case NOTIMP:
|
|
case REFUSED:
|
|
default:
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
break;
|
|
}
|
|
return (-1);
|
|
}
|
|
return (ancount);
|
|
}
|
|
|
|
/*
|
|
* Formulate a normal query, send, and retrieve answer in supplied buffer.
|
|
* Return the size of the response on success, -1 on error.
|
|
* If enabled, implement search rules until answer or unrecoverable failure
|
|
* is detected. Error code, if any, is left in h_errno.
|
|
*/
|
|
static int
|
|
res_searchN(const char *name, struct res_target *target, res_state res)
|
|
{
|
|
const char *cp, * const *domain;
|
|
HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
|
|
u_int dots;
|
|
int trailing_dot, ret, saved_herrno;
|
|
int got_nodata = 0, got_servfail = 0, root_on_list = 0;
|
|
int tried_as_is = 0;
|
|
int searched = 0;
|
|
char abuf[MAXDNAME];
|
|
|
|
errno = 0;
|
|
RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */
|
|
dots = 0;
|
|
for (cp = name; *cp; cp++)
|
|
dots += (*cp == '.');
|
|
trailing_dot = 0;
|
|
if (cp > name && *--cp == '.')
|
|
trailing_dot++;
|
|
|
|
/*
|
|
* if there aren't any dots, it could be a user-level alias
|
|
*/
|
|
if (!dots &&
|
|
(cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL)
|
|
return (res_queryN(cp, target, res));
|
|
|
|
/*
|
|
* If there are enough dots in the name, let's just give it a
|
|
* try 'as is'. The threshold can be set with the "ndots" option.
|
|
* Also, query 'as is', if there is a trailing dot in the name.
|
|
*/
|
|
saved_herrno = -1;
|
|
if (dots >= res->ndots || trailing_dot) {
|
|
ret = res_querydomainN(name, NULL, target, res);
|
|
if (ret > 0 || trailing_dot)
|
|
return (ret);
|
|
if (errno == ECONNREFUSED) {
|
|
RES_SET_H_ERRNO(res, TRY_AGAIN);
|
|
return (-1);
|
|
}
|
|
switch (res->res_h_errno) {
|
|
case NO_DATA:
|
|
case HOST_NOT_FOUND:
|
|
break;
|
|
case TRY_AGAIN:
|
|
if (hp->rcode == SERVFAIL)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
default:
|
|
return (-1);
|
|
}
|
|
saved_herrno = res->res_h_errno;
|
|
tried_as_is++;
|
|
}
|
|
|
|
/*
|
|
* We do at least one level of search if
|
|
* - there is no dot and RES_DEFNAME is set, or
|
|
* - there is at least one dot, there is no trailing dot,
|
|
* and RES_DNSRCH is set.
|
|
*/
|
|
if ((!dots && (res->options & RES_DEFNAMES)) ||
|
|
(dots && !trailing_dot && (res->options & RES_DNSRCH))) {
|
|
int done = 0;
|
|
|
|
for (domain = (const char * const *)res->dnsrch;
|
|
*domain && !done;
|
|
domain++) {
|
|
searched = 1;
|
|
|
|
if (domain[0][0] == '\0' ||
|
|
(domain[0][0] == '.' && domain[0][1] == '\0'))
|
|
root_on_list++;
|
|
|
|
if (root_on_list && tried_as_is)
|
|
continue;
|
|
|
|
ret = res_querydomainN(name, *domain, target, res);
|
|
if (ret > 0)
|
|
return (ret);
|
|
|
|
/*
|
|
* If no server present, give up.
|
|
* If name isn't found in this domain,
|
|
* keep trying higher domains in the search list
|
|
* (if that's enabled).
|
|
* On a NO_DATA error, keep trying, otherwise
|
|
* a wildcard entry of another type could keep us
|
|
* from finding this entry higher in the domain.
|
|
* If we get some other error (negative answer or
|
|
* server failure), then stop searching up,
|
|
* but try the input name below in case it's
|
|
* fully-qualified.
|
|
*/
|
|
if (errno == ECONNREFUSED) {
|
|
RES_SET_H_ERRNO(res, TRY_AGAIN);
|
|
return (-1);
|
|
}
|
|
|
|
switch (res->res_h_errno) {
|
|
case NO_DATA:
|
|
got_nodata++;
|
|
/* FALLTHROUGH */
|
|
case HOST_NOT_FOUND:
|
|
/* keep trying */
|
|
break;
|
|
case TRY_AGAIN:
|
|
got_servfail++;
|
|
if (hp->rcode == SERVFAIL) {
|
|
/* try next search element, if any */
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
default:
|
|
/* anything else implies that we're done */
|
|
done++;
|
|
}
|
|
/*
|
|
* if we got here for some reason other than DNSRCH,
|
|
* we only wanted one iteration of the loop, so stop.
|
|
*/
|
|
if (!(res->options & RES_DNSRCH))
|
|
done++;
|
|
}
|
|
}
|
|
|
|
switch (res->res_h_errno) {
|
|
case NO_DATA:
|
|
case HOST_NOT_FOUND:
|
|
break;
|
|
case TRY_AGAIN:
|
|
if (hp->rcode == SERVFAIL)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
default:
|
|
goto giveup;
|
|
}
|
|
|
|
/*
|
|
* If the query has not already been tried as is then try it
|
|
* unless RES_NOTLDQUERY is set and there were no dots.
|
|
*/
|
|
if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) &&
|
|
!(tried_as_is || root_on_list)) {
|
|
ret = res_querydomainN(name, NULL, target, res);
|
|
if (ret > 0)
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* if we got here, we didn't satisfy the search.
|
|
* if we did an initial full query, return that query's h_errno
|
|
* (note that we wouldn't be here if that query had succeeded).
|
|
* else if we ever got a nodata, send that back as the reason.
|
|
* else send back meaningless h_errno, that being the one from
|
|
* the last DNSRCH we did.
|
|
*/
|
|
giveup:
|
|
if (saved_herrno != -1)
|
|
RES_SET_H_ERRNO(res, saved_herrno);
|
|
else if (got_nodata)
|
|
RES_SET_H_ERRNO(res, NO_DATA);
|
|
else if (got_servfail)
|
|
RES_SET_H_ERRNO(res, TRY_AGAIN);
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* Perform a call on res_query on the concatenation of name and domain,
|
|
* removing a trailing dot from name if domain is NULL.
|
|
*/
|
|
static int
|
|
res_querydomainN(const char *name, const char *domain,
|
|
struct res_target *target, res_state res)
|
|
{
|
|
char nbuf[MAXDNAME];
|
|
const char *longname = nbuf;
|
|
size_t n, d;
|
|
|
|
#ifdef DEBUG
|
|
if (res->options & RES_DEBUG)
|
|
printf(";; res_querydomain(%s, %s)\n",
|
|
name, domain?domain:"<Nil>");
|
|
#endif
|
|
if (domain == NULL) {
|
|
/*
|
|
* Check for trailing '.';
|
|
* copy without '.' if present.
|
|
*/
|
|
n = strlen(name);
|
|
if (n >= MAXDNAME) {
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (-1);
|
|
}
|
|
if (n > 0 && name[--n] == '.') {
|
|
strncpy(nbuf, name, n);
|
|
nbuf[n] = '\0';
|
|
} else
|
|
longname = name;
|
|
} else {
|
|
n = strlen(name);
|
|
d = strlen(domain);
|
|
if (n + d + 1 >= MAXDNAME) {
|
|
RES_SET_H_ERRNO(res, NO_RECOVERY);
|
|
return (-1);
|
|
}
|
|
snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
|
|
}
|
|
return (res_queryN(longname, target, res));
|
|
}
|