michael@0: /*	$NetBSD: getaddrinfo.c,v 1.82 2006/03/25 12:09:40 rpaulo Exp $	*/
michael@0: /*	$KAME: getaddrinfo.c,v 1.29 2000/08/31 17:26:57 itojun Exp $	*/
michael@0: 
michael@0: /*
michael@0:  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
michael@0:  * All rights reserved.
michael@0:  *
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 1. Redistributions of source code must retain the above copyright
michael@0:  *    notice, this list of conditions and the following disclaimer.
michael@0:  * 2. Redistributions in binary form must reproduce the above copyright
michael@0:  *    notice, this list of conditions and the following disclaimer in the
michael@0:  *    documentation and/or other materials provided with the distribution.
michael@0:  * 3. Neither the name of the project nor the names of its contributors
michael@0:  *    may be used to endorse or promote products derived from this software
michael@0:  *    without specific prior written permission.
michael@0:  *
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
michael@0:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
michael@0:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
michael@0:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
michael@0:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
michael@0:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
michael@0:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
michael@0:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
michael@0:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
michael@0:  * SUCH DAMAGE.
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  * This version of getaddrinfo.c is derived from Android 2.3 "Gingerbread",
michael@0:  * which contains uncredited changes by Android/Google developers.  It has
michael@0:  * been modified in 2011 for use in the Android build of Mozilla Firefox by
michael@0:  * Mozilla contributors (including Michael Edwards <m.k.edwards@gmail.com>,
michael@0:  * and Steve Workman <sjhworkman@gmail.com>).
michael@0:  * These changes are offered under the same license as the original NetBSD
michael@0:  * file, whose copyright and license are unchanged above.
michael@0:  */
michael@0: #define ANDROID_CHANGES 1
michael@0: #define INET6 1
michael@0: 
michael@0: /*
michael@0:  * Issues to be discussed:
michael@0:  * - Return values.  There are nonstandard return values defined and used
michael@0:  *   in the source code.  This is because RFC2553 is silent about which error
michael@0:  *   code must be returned for which situation.
michael@0:  * - IPv4 classful (shortened) form.  RFC2553 is silent about it.  XNET 5.2
michael@0:  *   says to use inet_aton() to convert IPv4 numeric to binary (alows
michael@0:  *   classful form as a result).
michael@0:  *   current code - disallow classful form for IPv4 (due to use of inet_pton).
michael@0:  * - freeaddrinfo(NULL).  RFC2553 is silent about it.  XNET 5.2 says it is
michael@0:  *   invalid.
michael@0:  *   current code - SEGV on freeaddrinfo(NULL)
michael@0:  * Note:
michael@0:  * - We use getipnodebyname() just for thread-safeness.  There's no intent
michael@0:  *   to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to
michael@0:  *   getipnodebyname().
michael@0:  * - MOZILLA: Thread safeness for pre-Honeycomb Android versions implemented by
michael@0:  *   way of open/gets/close and mmap rather than fopen/fgets/fclose.  Affects
michael@0:  *   _files_getaddrinfo for hosts file.  Note: Honeycomb and later versions use
michael@0:  *   a thread-safe stdio, so for those versions normal Bionic libc getaddrinfo
michael@0:  *   is used.
michael@0:  * - The code filters out AFs that are not supported by the kernel,
michael@0:  *   when globbing NULL hostname (to loopback, or wildcard).  Is it the right
michael@0:  *   thing to do?  What is the relationship with post-RFC2553 AI_ADDRCONFIG
michael@0:  *   in ai_flags?
michael@0:  * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
michael@0:  *   (1) what should we do against numeric hostname (2) what should we do
michael@0:  *   against NULL hostname (3) what is AI_ADDRCONFIG itself.  AF not ready?
michael@0:  *   non-loopback address configured?  global address configured?
michael@0:  * - To avoid search order issue, we have a big amount of code duplicate
michael@0:  *   from gethnamaddr.c and some other places.  The issues that there's no
michael@0:  *   lower layer function to lookup "IPv4 or IPv6" record.  Calling
michael@0:  *   gethostbyname2 from getaddrinfo will end up in wrong search order, as
michael@0:  *   follows:
michael@0:  *	- The code makes use of following calls when asked to resolver with
michael@0:  *	  ai_family  = PF_UNSPEC:
michael@0:  *		getipnodebyname(host, AF_INET6);
michael@0:  *		getipnodebyname(host, AF_INET);
michael@0:  *	  This will result in the following queries if the node is configure to
michael@0:  *	  prefer /etc/hosts than DNS:
michael@0:  *		lookup /etc/hosts for IPv6 address
michael@0:  *		lookup DNS for IPv6 address
michael@0:  *		lookup /etc/hosts for IPv4 address
michael@0:  *		lookup DNS for IPv4 address
michael@0:  *	  which may not meet people's requirement.
michael@0:  *	  The right thing to happen is to have underlying layer which does
michael@0:  *	  PF_UNSPEC lookup (lookup both) and return chain of addrinfos.
michael@0:  *	  This would result in a bit of code duplicate with _dns_ghbyname() and
michael@0:  *	  friends.
michael@0:  */
michael@0: 
michael@0: #include <fcntl.h>
michael@0: #include <sys/cdefs.h>
michael@0: #include <sys/types.h>
michael@0: #include <sys/stat.h>
michael@0: #include <sys/param.h>
michael@0: #include <sys/socket.h>
michael@0: #include <sys/un.h>
michael@0: #include <sys/mman.h>
michael@0: #include <net/if.h>
michael@0: #include <netinet/in.h>
michael@0: #include <arpa/inet.h>
michael@0: #include "arpa_nameser.h"
michael@0: #include <assert.h>
michael@0: #include <ctype.h>
michael@0: #include <errno.h>
michael@0: #include <netdb.h>
michael@0: #include "resolv_private.h"
michael@0: #include <stddef.h>
michael@0: #include <stdlib.h>
michael@0: #include <string.h>
michael@0: #include <unistd.h>
michael@0: 
michael@0: #include <syslog.h>
michael@0: #include <stdarg.h>
michael@0: #include "nsswitch.h"
michael@0: 
michael@0: #ifdef MOZ_GETADDRINFO_LOG_VERBOSE
michael@0: #include <android/log.h>
michael@0: #endif
michael@0: 
michael@0: #ifdef ANDROID_CHANGES
michael@0: #include <sys/system_properties.h>
michael@0: #endif /* ANDROID_CHANGES */
michael@0: 
michael@0: typedef struct _pseudo_FILE {
michael@0:     int fd;
michael@0:     off_t maplen;
michael@0:     void* mapping;
michael@0:     off_t offset;
michael@0: } _pseudo_FILE;
michael@0: 
michael@0: #define _PSEUDO_FILE_INITIALIZER { -1, 0, MAP_FAILED, 0 }
michael@0: 
michael@0: static void
michael@0: _pseudo_fclose(_pseudo_FILE * __restrict__ fp)
michael@0: {
michael@0:     assert(fp);
michael@0:     fp->offset = 0;
michael@0:     if (fp->mapping != MAP_FAILED) {
michael@0:         (void) munmap(fp->mapping, fp->maplen);
michael@0:         fp->mapping = MAP_FAILED;
michael@0:     }
michael@0:     fp->maplen = 0;
michael@0:     if (fp->fd != -1) {
michael@0:         (void) close(fp->fd);
michael@0:         fp->fd = -1;
michael@0:     }
michael@0: }
michael@0: 
michael@0: static _pseudo_FILE *
michael@0: _pseudo_fopen_r(_pseudo_FILE * __restrict__ fp, const char* fname)
michael@0: {
michael@0:     struct stat statbuf;
michael@0:     assert(fp);
michael@0:     fp->fd = open(fname, O_RDONLY);
michael@0:     if (fp->fd < 0) {
michael@0:         fp->fd = -1;
michael@0:         return NULL;
michael@0:     }
michael@0:     if ((0 != fstat(fp->fd, &statbuf)) || (statbuf.st_size <= 0)) {
michael@0:         close(fp->fd);
michael@0:         fp->fd = -1;
michael@0:         return NULL;
michael@0:     }
michael@0:     fp->maplen = statbuf.st_size;
michael@0:     fp->mapping = mmap(NULL, fp->maplen, PROT_READ, MAP_PRIVATE, fp->fd, 0);
michael@0:     if (fp->mapping == MAP_FAILED) {
michael@0:         close(fp->fd);
michael@0:         fp->fd = -1;
michael@0:         return NULL;
michael@0:     }
michael@0:     fp->offset = 0;
michael@0:     return fp;
michael@0: }
michael@0: 
michael@0: static void
michael@0: _pseudo_rewind(_pseudo_FILE * __restrict__ fp)
michael@0: {
michael@0:     assert(fp);
michael@0:     fp->offset = 0;
michael@0: }
michael@0: 
michael@0: static char*
michael@0: _pseudo_fgets(char* buf, int bufsize, _pseudo_FILE * __restrict__ fp)
michael@0: {
michael@0:     char* current;
michael@0:     char* endp;
michael@0:     int maxcopy;
michael@0:     assert(fp);
michael@0:     maxcopy = fp->maplen - fp->offset;
michael@0:     if (fp->mapping == MAP_FAILED)
michael@0:         return NULL;
michael@0:     if (maxcopy > bufsize - 1)
michael@0:         maxcopy = bufsize - 1;
michael@0:     if (maxcopy <= 0)
michael@0:         return NULL;
michael@0:     current = ((char*) fp->mapping) + fp->offset;
michael@0:     endp = memccpy(buf, current, '\n', maxcopy);
michael@0:     if (endp)
michael@0:         maxcopy = endp - buf;
michael@0:     buf[maxcopy] = '\0';
michael@0:     fp->offset += maxcopy;
michael@0:     return buf;
michael@0: }
michael@0: 
michael@0: typedef union sockaddr_union {
michael@0:     struct sockaddr     generic;
michael@0:     struct sockaddr_in  in;
michael@0:     struct sockaddr_in6 in6;
michael@0: } sockaddr_union;
michael@0: 
michael@0: #define SUCCESS 0
michael@0: #define ANY 0
michael@0: #define YES 1
michael@0: #define NO  0
michael@0: 
michael@0: static const char in_addrany[] = { 0, 0, 0, 0 };
michael@0: static const char in_loopback[] = { 127, 0, 0, 1 };
michael@0: #ifdef INET6
michael@0: static const char in6_addrany[] = {
michael@0: 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
michael@0: };
michael@0: static const char in6_loopback[] = {
michael@0: 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
michael@0: };
michael@0: #endif
michael@0: 
michael@0: static const struct afd {
michael@0: 	int a_af;
michael@0: 	int a_addrlen;
michael@0: 	int a_socklen;
michael@0: 	int a_off;
michael@0: 	const char *a_addrany;
michael@0: 	const char *a_loopback;
michael@0: 	int a_scoped;
michael@0: } afdl [] = {
michael@0: #ifdef INET6
michael@0: 	{PF_INET6, sizeof(struct in6_addr),
michael@0: 	 sizeof(struct sockaddr_in6),
michael@0: 	 offsetof(struct sockaddr_in6, sin6_addr),
michael@0: 	 in6_addrany, in6_loopback, 1},
michael@0: #endif
michael@0: 	{PF_INET, sizeof(struct in_addr),
michael@0: 	 sizeof(struct sockaddr_in),
michael@0: 	 offsetof(struct sockaddr_in, sin_addr),
michael@0: 	 in_addrany, in_loopback, 0},
michael@0: 	{0, 0, 0, 0, NULL, NULL, 0},
michael@0: };
michael@0: 
michael@0: struct explore {
michael@0: 	int e_af;
michael@0: 	int e_socktype;
michael@0: 	int e_protocol;
michael@0: 	const char *e_protostr;
michael@0: 	int e_wild;
michael@0: #define WILD_AF(ex)		((ex)->e_wild & 0x01)
michael@0: #define WILD_SOCKTYPE(ex)	((ex)->e_wild & 0x02)
michael@0: #define WILD_PROTOCOL(ex)	((ex)->e_wild & 0x04)
michael@0: };
michael@0: 
michael@0: static const struct explore explore[] = {
michael@0: #if 0
michael@0: 	{ PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
michael@0: #endif
michael@0: #ifdef INET6
michael@0: 	{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
michael@0: 	{ PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
michael@0: 	{ PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
michael@0: #endif
michael@0: 	{ PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
michael@0: 	{ PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
michael@0: 	{ PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
michael@0: 	{ PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
michael@0: 	{ PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
michael@0: 	{ PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
michael@0: 	{ -1, 0, 0, NULL, 0 },
michael@0: };
michael@0: 
michael@0: #ifdef INET6
michael@0: #define PTON_MAX	16
michael@0: #else
michael@0: #define PTON_MAX	4
michael@0: #endif
michael@0: 
michael@0: static const ns_src default_dns_files[] = {
michael@0: 	{ NSSRC_FILES, 	NS_SUCCESS },
michael@0: 	{ NSSRC_DNS, 	NS_SUCCESS },
michael@0: 	{ 0, 0 }
michael@0: };
michael@0: 
michael@0: #define MAXPACKET	(64*1024)
michael@0: 
michael@0: typedef union {
michael@0: 	HEADER hdr;
michael@0: 	u_char buf[MAXPACKET];
michael@0: } querybuf;
michael@0: 
michael@0: struct res_target {
michael@0: 	struct res_target *next;
michael@0: 	const char *name;	/* domain name */
michael@0: 	int qclass, qtype;	/* class and type of query */
michael@0: 	u_char *answer;		/* buffer to put answer */
michael@0: 	int anslen;		/* size of answer buffer */
michael@0: 	int n;			/* result length */
michael@0: };
michael@0: 
michael@0: static int str2number(const char *);
michael@0: static int explore_fqdn(const struct addrinfo *, const char *,
michael@0: 	const char *, struct addrinfo **);
michael@0: static int explore_null(const struct addrinfo *,
michael@0: 	const char *, struct addrinfo **);
michael@0: static int explore_numeric(const struct addrinfo *, const char *,
michael@0: 	const char *, struct addrinfo **, const char *);
michael@0: static int explore_numeric_scope(const struct addrinfo *, const char *,
michael@0: 	const char *, struct addrinfo **);
michael@0: static int get_canonname(const struct addrinfo *,
michael@0: 	struct addrinfo *, const char *);
michael@0: static struct addrinfo *get_ai(const struct addrinfo *,
michael@0: 	const struct afd *, const char *);
michael@0: static int get_portmatch(const struct addrinfo *, const char *);
michael@0: static int get_port(const struct addrinfo *, const char *, int);
michael@0: static const struct afd *find_afd(int);
michael@0: #ifdef INET6
michael@0: static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
michael@0: #endif
michael@0: 
michael@0: static struct addrinfo *getanswer(const querybuf *, int, const char *, int,
michael@0: 	const struct addrinfo *);
michael@0: static int _dns_getaddrinfo(void *, void *, va_list);
michael@0: static void _sethtent(_pseudo_FILE * __restrict__);
michael@0: static void _endhtent(_pseudo_FILE * __restrict__);
michael@0: static struct addrinfo *_gethtent(_pseudo_FILE * __restrict__, const char *,
michael@0:     const struct addrinfo *);
michael@0: static int _files_getaddrinfo(void *, void *, va_list);
michael@0: 
michael@0: static int res_queryN(const char *, struct res_target *, res_state);
michael@0: static int res_searchN(const char *, struct res_target *, res_state);
michael@0: static int res_querydomainN(const char *, const char *,
michael@0: 	struct res_target *, res_state);
michael@0: 
michael@0: static const char * const ai_errlist[] = {
michael@0: 	"Success",
michael@0: 	"Address family for hostname not supported",	/* EAI_ADDRFAMILY */
michael@0: 	"Temporary failure in name resolution",		/* EAI_AGAIN      */
michael@0: 	"Invalid value for ai_flags",		       	/* EAI_BADFLAGS   */
michael@0: 	"Non-recoverable failure in name resolution", 	/* EAI_FAIL       */
michael@0: 	"ai_family not supported",			/* EAI_FAMILY     */
michael@0: 	"Memory allocation failure", 			/* EAI_MEMORY     */
michael@0: 	"No address associated with hostname", 		/* EAI_NODATA     */
michael@0: 	"hostname nor servname provided, or not known",	/* EAI_NONAME     */
michael@0: 	"servname not supported for ai_socktype",	/* EAI_SERVICE    */
michael@0: 	"ai_socktype not supported", 			/* EAI_SOCKTYPE   */
michael@0: 	"System error returned in errno", 		/* EAI_SYSTEM     */
michael@0: 	"Invalid value for hints",			/* EAI_BADHINTS	  */
michael@0: 	"Resolved protocol is unknown",			/* EAI_PROTOCOL   */
michael@0: 	"Argument buffer overflow",			/* EAI_OVERFLOW   */
michael@0: 	"Unknown error", 				/* EAI_MAX        */
michael@0: };
michael@0: 
michael@0: /* XXX macros that make external reference is BAD. */
michael@0: 
michael@0: #define GET_AI(ai, afd, addr) 					\
michael@0: do { 								\
michael@0: 	/* external reference: pai, error, and label free */ 	\
michael@0: 	(ai) = get_ai(pai, (afd), (addr)); 			\
michael@0: 	if ((ai) == NULL) { 					\
michael@0: 		error = EAI_MEMORY; 				\
michael@0: 		goto free; 					\
michael@0: 	} 							\
michael@0: } while (/*CONSTCOND*/0)
michael@0: 
michael@0: #define GET_PORT(ai, serv) 					\
michael@0: do { 								\
michael@0: 	/* external reference: error and label free */ 		\
michael@0: 	error = get_port((ai), (serv), 0); 			\
michael@0: 	if (error != 0) 					\
michael@0: 		goto free; 					\
michael@0: } while (/*CONSTCOND*/0)
michael@0: 
michael@0: #define GET_CANONNAME(ai, str) 					\
michael@0: do { 								\
michael@0: 	/* external reference: pai, error and label free */ 	\
michael@0: 	error = get_canonname(pai, (ai), (str)); 		\
michael@0: 	if (error != 0) 					\
michael@0: 		goto free; 					\
michael@0: } while (/*CONSTCOND*/0)
michael@0: 
michael@0: #define ERR(err) 						\
michael@0: do { 								\
michael@0: 	/* external reference: error, and label bad */ 		\
michael@0: 	error = (err); 						\
michael@0: 	goto bad; 						\
michael@0: 	/*NOTREACHED*/ 						\
michael@0: } while (/*CONSTCOND*/0)
michael@0: 
michael@0: #define MATCH_FAMILY(x, y, w) 						\
michael@0: 	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || 	\
michael@0: 	    (y) == PF_UNSPEC)))
michael@0: #define MATCH(x, y, w) 							\
michael@0: 	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
michael@0: 
michael@0: #pragma GCC visibility push(default)
michael@0: 
michael@0: extern const char *
michael@0: __wrap_gai_strerror(int ecode);
michael@0: extern void
michael@0: __wrap_freeaddrinfo(struct addrinfo *ai);
michael@0: extern int
michael@0: __wrap_getaddrinfo(const char *hostname, const char *servname,
michael@0:     const struct addrinfo *hints, struct addrinfo **res);
michael@0: 
michael@0: int android_sdk_version;
michael@0: 
michael@0: #pragma GCC visibility pop
michael@0: 
michael@0: int android_sdk_version = -1;
michael@0: 
michael@0: static int honeycomb_or_later()
michael@0: {
michael@0: #ifdef MOZ_GETADDRINFO_LOG_VERBOSE
michael@0: 	__android_log_print(ANDROID_LOG_INFO, "getaddrinfo",
michael@0: 		"I am%s Honeycomb\n",
michael@0: 		(android_sdk_version >= 11) ? "" : " not");
michael@0: #endif
michael@0: 	return android_sdk_version >= 11;
michael@0: }
michael@0: 
michael@0: const char *
michael@0: __wrap_gai_strerror(int ecode)
michael@0: {
michael@0: 	if (honeycomb_or_later())
michael@0: 		return gai_strerror(ecode);
michael@0: 	if (ecode < 0 || ecode > EAI_MAX)
michael@0: 		ecode = EAI_MAX;
michael@0: 	return ai_errlist[ecode];
michael@0: }
michael@0: 
michael@0: void
michael@0: __wrap_freeaddrinfo(struct addrinfo *ai)
michael@0: {
michael@0: 	struct addrinfo *next;
michael@0: 
michael@0: 	if (honeycomb_or_later()) {
michael@0: 		freeaddrinfo(ai);
michael@0: 		return;
michael@0: 	}
michael@0: 
michael@0: 	assert(ai != NULL);
michael@0: 
michael@0: 	do {
michael@0: 		next = ai->ai_next;
michael@0: 		if (ai->ai_canonname)
michael@0: 			free(ai->ai_canonname);
michael@0: 		/* no need to free(ai->ai_addr) */
michael@0: 		free(ai);
michael@0: 		ai = next;
michael@0: 	} while (ai);
michael@0: }
michael@0: 
michael@0: static int
michael@0: str2number(const char *p)
michael@0: {
michael@0: 	char *ep;
michael@0: 	unsigned long v;
michael@0: 
michael@0: 	assert(p != NULL);
michael@0: 
michael@0: 	if (*p == '\0')
michael@0: 		return -1;
michael@0: 	ep = NULL;
michael@0: 	errno = 0;
michael@0: 	v = strtoul(p, &ep, 10);
michael@0: 	if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX)
michael@0: 		return v;
michael@0: 	else
michael@0: 		return -1;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Connect a UDP socket to a given unicast address. This will cause no network
michael@0:  * traffic, but will fail fast if the system has no or limited reachability to
michael@0:  * the destination (e.g., no IPv4 address, no IPv6 default route, ...).
michael@0:  */
michael@0: static int
michael@0: _test_connect(int pf, struct sockaddr *addr, size_t addrlen) {
michael@0: 	int s = socket(pf, SOCK_DGRAM, IPPROTO_UDP);
michael@0: 	if (s < 0)
michael@0: 		return 0;
michael@0: 	int ret;
michael@0: 	do {
michael@0: 		ret = connect(s, addr, addrlen);
michael@0: 	} while (ret < 0 && errno == EINTR);
michael@0: 	int success = (ret == 0);
michael@0: 	do {
michael@0: 		ret = close(s);
michael@0: 	} while (ret < 0 && errno == EINTR);
michael@0: 	return success;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * The following functions determine whether IPv4 or IPv6 connectivity is
michael@0:  * available in order to implement AI_ADDRCONFIG.
michael@0:  *
michael@0:  * Strictly speaking, AI_ADDRCONFIG should not look at whether connectivity is
michael@0:  * available, but whether addresses of the specified family are "configured
michael@0:  * on the local system". However, bionic doesn't currently support getifaddrs,
michael@0:  * so checking for connectivity is the next best thing.
michael@0:  */
michael@0: static int
michael@0: _have_ipv6() {
michael@0: 	static const struct sockaddr_in6 sin6_test = {
michael@0: 		.sin6_family = AF_INET6,
michael@0: 		.sin6_addr.s6_addr = {  // 2000::
michael@0: 			0x20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
michael@0: 		};
michael@0:         sockaddr_union addr = { .in6 = sin6_test };
michael@0: 	return _test_connect(PF_INET6, &addr.generic, sizeof(addr.in6));
michael@0: }
michael@0: 
michael@0: static int
michael@0: _have_ipv4() {
michael@0: 	static const struct sockaddr_in sin_test = {
michael@0: 		.sin_family = AF_INET,
michael@0: 		.sin_addr.s_addr = __constant_htonl(0x08080808L)  // 8.8.8.8
michael@0: 	};
michael@0:         sockaddr_union addr = { .in = sin_test };
michael@0:         return _test_connect(PF_INET, &addr.generic, sizeof(addr.in));
michael@0: }
michael@0: 
michael@0: int
michael@0: __wrap_getaddrinfo(const char *hostname, const char *servname,
michael@0:     const struct addrinfo *hints, struct addrinfo **res)
michael@0: {
michael@0: 	struct addrinfo sentinel;
michael@0: 	struct addrinfo *cur;
michael@0: 	int error = 0;
michael@0: 	struct addrinfo ai;
michael@0: 	struct addrinfo ai0;
michael@0: 	struct addrinfo *pai;
michael@0: 	const struct explore *ex;
michael@0: 
michael@0: 	if (honeycomb_or_later())
michael@0: 		return getaddrinfo(hostname, servname, hints, res);
michael@0: 
michael@0: 	/* hostname is allowed to be NULL */
michael@0: 	/* servname is allowed to be NULL */
michael@0: 	/* hints is allowed to be NULL */
michael@0: 	assert(res != NULL);
michael@0: 
michael@0: 	memset(&sentinel, 0, sizeof(sentinel));
michael@0: 	cur = &sentinel;
michael@0: 	pai = &ai;
michael@0: 	pai->ai_flags = 0;
michael@0: 	pai->ai_family = PF_UNSPEC;
michael@0: 	pai->ai_socktype = ANY;
michael@0: 	pai->ai_protocol = ANY;
michael@0: 	pai->ai_addrlen = 0;
michael@0: 	pai->ai_canonname = NULL;
michael@0: 	pai->ai_addr = NULL;
michael@0: 	pai->ai_next = NULL;
michael@0: 
michael@0: 	if (hostname == NULL && servname == NULL)
michael@0: 		return EAI_NONAME;
michael@0: 	if (hints) {
michael@0: 		/* error check for hints */
michael@0: 		if (hints->ai_addrlen || hints->ai_canonname ||
michael@0: 		    hints->ai_addr || hints->ai_next)
michael@0: 			ERR(EAI_BADHINTS); /* xxx */
michael@0: 		if (hints->ai_flags & ~AI_MASK)
michael@0: 			ERR(EAI_BADFLAGS);
michael@0: 		switch (hints->ai_family) {
michael@0: 		case PF_UNSPEC:
michael@0: 		case PF_INET:
michael@0: #ifdef INET6
michael@0: 		case PF_INET6:
michael@0: #endif
michael@0: 			break;
michael@0: 		default:
michael@0: 			ERR(EAI_FAMILY);
michael@0: 		}
michael@0: 		memcpy(pai, hints, sizeof(*pai));
michael@0: 
michael@0: 		/*
michael@0: 		 * if both socktype/protocol are specified, check if they
michael@0: 		 * are meaningful combination.
michael@0: 		 */
michael@0: 		if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
michael@0: 			for (ex = explore; ex->e_af >= 0; ex++) {
michael@0: 				if (pai->ai_family != ex->e_af)
michael@0: 					continue;
michael@0: 				if (ex->e_socktype == ANY)
michael@0: 					continue;
michael@0: 				if (ex->e_protocol == ANY)
michael@0: 					continue;
michael@0: 				if (pai->ai_socktype == ex->e_socktype
michael@0: 				 && pai->ai_protocol != ex->e_protocol) {
michael@0: 					ERR(EAI_BADHINTS);
michael@0: 				}
michael@0: 			}
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * check for special cases.  (1) numeric servname is disallowed if
michael@0: 	 * socktype/protocol are left unspecified. (2) servname is disallowed
michael@0: 	 * for raw and other inet{,6} sockets.
michael@0: 	 */
michael@0: 	if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
michael@0: #ifdef PF_INET6
michael@0: 	 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
michael@0: #endif
michael@0: 	    ) {
michael@0: 		ai0 = *pai;	/* backup *pai */
michael@0: 
michael@0: 		if (pai->ai_family == PF_UNSPEC) {
michael@0: #ifdef PF_INET6
michael@0: 			pai->ai_family = PF_INET6;
michael@0: #else
michael@0: 			pai->ai_family = PF_INET;
michael@0: #endif
michael@0: 		}
michael@0: 		error = get_portmatch(pai, servname);
michael@0: 		if (error)
michael@0: 			ERR(error);
michael@0: 
michael@0: 		*pai = ai0;
michael@0: 	}
michael@0: 
michael@0: 	ai0 = *pai;
michael@0: 
michael@0: 	/* NULL hostname, or numeric hostname */
michael@0: 	for (ex = explore; ex->e_af >= 0; ex++) {
michael@0: 		*pai = ai0;
michael@0: 
michael@0: 		/* PF_UNSPEC entries are prepared for DNS queries only */
michael@0: 		if (ex->e_af == PF_UNSPEC)
michael@0: 			continue;
michael@0: 
michael@0: 		if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
michael@0: 			continue;
michael@0: 		if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
michael@0: 			continue;
michael@0: 		if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
michael@0: 			continue;
michael@0: 
michael@0: 		if (pai->ai_family == PF_UNSPEC)
michael@0: 			pai->ai_family = ex->e_af;
michael@0: 		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
michael@0: 			pai->ai_socktype = ex->e_socktype;
michael@0: 		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
michael@0: 			pai->ai_protocol = ex->e_protocol;
michael@0: 
michael@0: 		if (hostname == NULL)
michael@0: 			error = explore_null(pai, servname, &cur->ai_next);
michael@0: 		else
michael@0: 			error = explore_numeric_scope(pai, hostname, servname,
michael@0: 			    &cur->ai_next);
michael@0: 
michael@0: 		if (error)
michael@0: 			goto free;
michael@0: 
michael@0: 		while (cur->ai_next)
michael@0: 			cur = cur->ai_next;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * XXX
michael@0: 	 * If numeric representation of AF1 can be interpreted as FQDN
michael@0: 	 * representation of AF2, we need to think again about the code below.
michael@0: 	 */
michael@0: 	if (sentinel.ai_next)
michael@0: 		goto good;
michael@0: 
michael@0: 	if (hostname == NULL)
michael@0: 		ERR(EAI_NODATA);
michael@0: 	if (pai->ai_flags & AI_NUMERICHOST)
michael@0: 		ERR(EAI_NONAME);
michael@0: 
michael@0: 	/*
michael@0: 	 * hostname as alphabetical name.
michael@0: 	 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
michael@0: 	 * outer loop by AFs.
michael@0: 	 */
michael@0: 	for (ex = explore; ex->e_af >= 0; ex++) {
michael@0: 		*pai = ai0;
michael@0: 
michael@0: 		/* require exact match for family field */
michael@0: 		if (pai->ai_family != ex->e_af)
michael@0: 			continue;
michael@0: 
michael@0: 		if (!MATCH(pai->ai_socktype, ex->e_socktype,
michael@0: 				WILD_SOCKTYPE(ex))) {
michael@0: 			continue;
michael@0: 		}
michael@0: 		if (!MATCH(pai->ai_protocol, ex->e_protocol,
michael@0: 				WILD_PROTOCOL(ex))) {
michael@0: 			continue;
michael@0: 		}
michael@0: 
michael@0: 		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
michael@0: 			pai->ai_socktype = ex->e_socktype;
michael@0: 		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
michael@0: 			pai->ai_protocol = ex->e_protocol;
michael@0: 
michael@0: 		error = explore_fqdn(pai, hostname, servname,
michael@0: 			&cur->ai_next);
michael@0: 
michael@0: 		while (cur && cur->ai_next)
michael@0: 			cur = cur->ai_next;
michael@0: 	}
michael@0: 
michael@0: 	/* XXX */
michael@0: 	if (sentinel.ai_next)
michael@0: 		error = 0;
michael@0: 
michael@0: 	if (error)
michael@0: 		goto free;
michael@0: 	if (error == 0) {
michael@0: 		if (sentinel.ai_next) {
michael@0:  good:
michael@0: 			*res = sentinel.ai_next;
michael@0: 			return SUCCESS;
michael@0: 		} else
michael@0: 			error = EAI_FAIL;
michael@0: 	}
michael@0:  free:
michael@0:  bad:
michael@0: 	if (sentinel.ai_next)
michael@0: 		__wrap_freeaddrinfo(sentinel.ai_next);
michael@0: 	*res = NULL;
michael@0: 	return error;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * FQDN hostname, DNS lookup
michael@0:  */
michael@0: static int
michael@0: explore_fqdn(const struct addrinfo *pai, const char *hostname,
michael@0:     const char *servname, struct addrinfo **res)
michael@0: {
michael@0: 	struct addrinfo *result;
michael@0: 	struct addrinfo *cur;
michael@0: 	int error = 0;
michael@0: 	static const ns_dtab dtab[] = {
michael@0: 		NS_FILES_CB(_files_getaddrinfo, NULL)
michael@0: 		{ NSSRC_DNS, _dns_getaddrinfo, NULL },	/* force -DHESIOD */
michael@0: 		NS_NIS_CB(_yp_getaddrinfo, NULL)
michael@0: 		{ 0, 0, 0 }
michael@0: 	};
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	/* hostname may be NULL */
michael@0: 	/* servname may be NULL */
michael@0: 	assert(res != NULL);
michael@0: 
michael@0: 	result = NULL;
michael@0: 
michael@0: 	/*
michael@0: 	 * if the servname does not match socktype/protocol, ignore it.
michael@0: 	 */
michael@0: 	if (get_portmatch(pai, servname) != 0)
michael@0: 		return 0;
michael@0: 
michael@0: 	switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
michael@0: 			default_dns_files, hostname, pai)) {
michael@0: 	case NS_TRYAGAIN:
michael@0: 		error = EAI_AGAIN;
michael@0: 		goto free;
michael@0: 	case NS_UNAVAIL:
michael@0: 		error = EAI_FAIL;
michael@0: 		goto free;
michael@0: 	case NS_NOTFOUND:
michael@0: 		error = EAI_NODATA;
michael@0: 		goto free;
michael@0: 	case NS_SUCCESS:
michael@0: 		error = 0;
michael@0: 		for (cur = result; cur; cur = cur->ai_next) {
michael@0: 			GET_PORT(cur, servname);
michael@0: 			/* canonname should be filled already */
michael@0: 		}
michael@0: 		break;
michael@0: 	}
michael@0: 
michael@0: 	*res = result;
michael@0: 
michael@0: 	return 0;
michael@0: 
michael@0: free:
michael@0: 	if (result)
michael@0: 		__wrap_freeaddrinfo(result);
michael@0: 	return error;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * hostname == NULL.
michael@0:  * passive socket -> anyaddr (0.0.0.0 or ::)
michael@0:  * non-passive socket -> localhost (127.0.0.1 or ::1)
michael@0:  */
michael@0: static int
michael@0: explore_null(const struct addrinfo *pai, const char *servname,
michael@0:     struct addrinfo **res)
michael@0: {
michael@0: 	int s;
michael@0: 	const struct afd *afd;
michael@0: 	struct addrinfo *cur;
michael@0: 	struct addrinfo sentinel;
michael@0: 	int error;
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	/* servname may be NULL */
michael@0: 	assert(res != NULL);
michael@0: 
michael@0: 	*res = NULL;
michael@0: 	sentinel.ai_next = NULL;
michael@0: 	cur = &sentinel;
michael@0: 
michael@0: 	/*
michael@0: 	 * filter out AFs that are not supported by the kernel
michael@0: 	 * XXX errno?
michael@0: 	 */
michael@0: 	s = socket(pai->ai_family, SOCK_DGRAM, 0);
michael@0: 	if (s < 0) {
michael@0: 		if (errno != EMFILE)
michael@0: 			return 0;
michael@0: 	} else
michael@0: 		close(s);
michael@0: 
michael@0: 	/*
michael@0: 	 * if the servname does not match socktype/protocol, ignore it.
michael@0: 	 */
michael@0: 	if (get_portmatch(pai, servname) != 0)
michael@0: 		return 0;
michael@0: 
michael@0: 	afd = find_afd(pai->ai_family);
michael@0: 	if (afd == NULL)
michael@0: 		return 0;
michael@0: 
michael@0: 	if (pai->ai_flags & AI_PASSIVE) {
michael@0: 		GET_AI(cur->ai_next, afd, afd->a_addrany);
michael@0: 		/* xxx meaningless?
michael@0: 		 * GET_CANONNAME(cur->ai_next, "anyaddr");
michael@0: 		 */
michael@0: 		GET_PORT(cur->ai_next, servname);
michael@0: 	} else {
michael@0: 		GET_AI(cur->ai_next, afd, afd->a_loopback);
michael@0: 		/* xxx meaningless?
michael@0: 		 * GET_CANONNAME(cur->ai_next, "localhost");
michael@0: 		 */
michael@0: 		GET_PORT(cur->ai_next, servname);
michael@0: 	}
michael@0: 	cur = cur->ai_next;
michael@0: 
michael@0: 	*res = sentinel.ai_next;
michael@0: 	return 0;
michael@0: 
michael@0: free:
michael@0: 	if (sentinel.ai_next)
michael@0: 		__wrap_freeaddrinfo(sentinel.ai_next);
michael@0: 	return error;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * numeric hostname
michael@0:  */
michael@0: static int
michael@0: explore_numeric(const struct addrinfo *pai, const char *hostname,
michael@0:     const char *servname, struct addrinfo **res, const char *canonname)
michael@0: {
michael@0: 	const struct afd *afd;
michael@0: 	struct addrinfo *cur;
michael@0: 	struct addrinfo sentinel;
michael@0: 	int error;
michael@0: 	char pton[PTON_MAX];
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	/* hostname may be NULL */
michael@0: 	/* servname may be NULL */
michael@0: 	assert(res != NULL);
michael@0: 
michael@0: 	*res = NULL;
michael@0: 	sentinel.ai_next = NULL;
michael@0: 	cur = &sentinel;
michael@0: 
michael@0: 	/*
michael@0: 	 * if the servname does not match socktype/protocol, ignore it.
michael@0: 	 */
michael@0: 	if (get_portmatch(pai, servname) != 0)
michael@0: 		return 0;
michael@0: 
michael@0: 	afd = find_afd(pai->ai_family);
michael@0: 	if (afd == NULL)
michael@0: 		return 0;
michael@0: 
michael@0: 	switch (afd->a_af) {
michael@0: #if 0 /*X/Open spec*/
michael@0: 	case AF_INET:
michael@0: 		if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
michael@0: 			if (pai->ai_family == afd->a_af ||
michael@0: 			    pai->ai_family == PF_UNSPEC /*?*/) {
michael@0: 				GET_AI(cur->ai_next, afd, pton);
michael@0: 				GET_PORT(cur->ai_next, servname);
michael@0: 				if ((pai->ai_flags & AI_CANONNAME)) {
michael@0: 					/*
michael@0: 					 * Set the numeric address itself as
michael@0: 					 * the canonical name, based on a
michael@0: 					 * clarification in rfc2553bis-03.
michael@0: 					 */
michael@0: 					GET_CANONNAME(cur->ai_next, canonname);
michael@0: 				}
michael@0: 				while (cur && cur->ai_next)
michael@0: 					cur = cur->ai_next;
michael@0: 			} else
michael@0: 				ERR(EAI_FAMILY);	/*xxx*/
michael@0: 		}
michael@0: 		break;
michael@0: #endif
michael@0: 	default:
michael@0: 		if (inet_pton(afd->a_af, hostname, pton) == 1) {
michael@0: 			if (pai->ai_family == afd->a_af ||
michael@0: 			    pai->ai_family == PF_UNSPEC /*?*/) {
michael@0: 				GET_AI(cur->ai_next, afd, pton);
michael@0: 				GET_PORT(cur->ai_next, servname);
michael@0: 				if ((pai->ai_flags & AI_CANONNAME)) {
michael@0: 					/*
michael@0: 					 * Set the numeric address itself as
michael@0: 					 * the canonical name, based on a
michael@0: 					 * clarification in rfc2553bis-03.
michael@0: 					 */
michael@0: 					GET_CANONNAME(cur->ai_next, canonname);
michael@0: 				}
michael@0: 				while (cur->ai_next)
michael@0: 					cur = cur->ai_next;
michael@0: 			} else
michael@0: 				ERR(EAI_FAMILY);	/*xxx*/
michael@0: 		}
michael@0: 		break;
michael@0: 	}
michael@0: 
michael@0: 	*res = sentinel.ai_next;
michael@0: 	return 0;
michael@0: 
michael@0: free:
michael@0: bad:
michael@0: 	if (sentinel.ai_next)
michael@0: 		__wrap_freeaddrinfo(sentinel.ai_next);
michael@0: 	return error;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * numeric hostname with scope
michael@0:  */
michael@0: static int
michael@0: explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
michael@0:     const char *servname, struct addrinfo **res)
michael@0: {
michael@0: #if !defined(SCOPE_DELIMITER) || !defined(INET6)
michael@0: 	return explore_numeric(pai, hostname, servname, res, hostname);
michael@0: #else
michael@0: 	const struct afd *afd;
michael@0: 	struct addrinfo *cur;
michael@0: 	int error;
michael@0: 	char *cp, *hostname2 = NULL, *scope, *addr;
michael@0: 	struct sockaddr_in6 *sin6;
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	/* hostname may be NULL */
michael@0: 	/* servname may be NULL */
michael@0: 	assert(res != NULL);
michael@0: 
michael@0: 	/*
michael@0: 	 * if the servname does not match socktype/protocol, ignore it.
michael@0: 	 */
michael@0: 	if (get_portmatch(pai, servname) != 0)
michael@0: 		return 0;
michael@0: 
michael@0: 	afd = find_afd(pai->ai_family);
michael@0: 	if (afd == NULL)
michael@0: 		return 0;
michael@0: 
michael@0: 	if (!afd->a_scoped)
michael@0: 		return explore_numeric(pai, hostname, servname, res, hostname);
michael@0: 
michael@0: 	cp = strchr(hostname, SCOPE_DELIMITER);
michael@0: 	if (cp == NULL)
michael@0: 		return explore_numeric(pai, hostname, servname, res, hostname);
michael@0: 
michael@0: 	/*
michael@0: 	 * Handle special case of <scoped_address><delimiter><scope id>
michael@0: 	 */
michael@0: 	hostname2 = strdup(hostname);
michael@0: 	if (hostname2 == NULL)
michael@0: 		return EAI_MEMORY;
michael@0: 	/* terminate at the delimiter */
michael@0: 	hostname2[cp - hostname] = '\0';
michael@0: 	addr = hostname2;
michael@0: 	scope = cp + 1;
michael@0: 
michael@0: 	error = explore_numeric(pai, addr, servname, res, hostname);
michael@0: 	if (error == 0) {
michael@0: 		u_int32_t scopeid;
michael@0: 
michael@0: 		for (cur = *res; cur; cur = cur->ai_next) {
michael@0: 			if (cur->ai_family != AF_INET6)
michael@0: 				continue;
michael@0: 			sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
michael@0: 			if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
michael@0: 				free(hostname2);
michael@0: 				return(EAI_NODATA); /* XXX: is return OK? */
michael@0: 			}
michael@0: 			sin6->sin6_scope_id = scopeid;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	free(hostname2);
michael@0: 
michael@0: 	return error;
michael@0: #endif
michael@0: }
michael@0: 
michael@0: static int
michael@0: get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
michael@0: {
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	assert(ai != NULL);
michael@0: 	assert(str != NULL);
michael@0: 
michael@0: 	if ((pai->ai_flags & AI_CANONNAME) != 0) {
michael@0: 		ai->ai_canonname = strdup(str);
michael@0: 		if (ai->ai_canonname == NULL)
michael@0: 			return EAI_MEMORY;
michael@0: 	}
michael@0: 	return 0;
michael@0: }
michael@0: 
michael@0: static struct addrinfo *
michael@0: get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
michael@0: {
michael@0: 	char *p;
michael@0: 	struct addrinfo *ai;
michael@0: 
michael@0: 	assert(pai != NULL);
michael@0: 	assert(afd != NULL);
michael@0: 	assert(addr != NULL);
michael@0: 
michael@0: 	ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
michael@0: 		+ (afd->a_socklen));
michael@0: 	if (ai == NULL)
michael@0: 		return NULL;
michael@0: 
michael@0: 	memcpy(ai, pai, sizeof(struct addrinfo));
michael@0: 	ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
michael@0: 	memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
michael@0: 
michael@0: #ifdef HAVE_SA_LEN
michael@0: 	ai->ai_addr->sa_len = afd->a_socklen;
michael@0: #endif
michael@0: 
michael@0: 	ai->ai_addrlen = afd->a_socklen;
michael@0: #if defined (__alpha__) || (defined(__i386__) && defined(_LP64)) || defined(__sparc64__)
michael@0: 	ai->__ai_pad0 = 0;
michael@0: #endif
michael@0: 	ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
michael@0: 	p = (char *)(void *)(ai->ai_addr);
michael@0: 	memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
michael@0: 	return ai;
michael@0: }
michael@0: 
michael@0: static int
michael@0: get_portmatch(const struct addrinfo *ai, const char *servname)
michael@0: {
michael@0: 
michael@0: 	assert(ai != NULL);
michael@0: 	/* servname may be NULL */
michael@0: 
michael@0: 	return get_port(ai, servname, 1);
michael@0: }
michael@0: 
michael@0: static int
michael@0: get_port(const struct addrinfo *ai, const char *servname, int matchonly)
michael@0: {
michael@0: 	const char *proto;
michael@0: 	struct servent *sp;
michael@0: 	int port;
michael@0: 	int allownumeric;
michael@0: 
michael@0: 	assert(ai != NULL);
michael@0: 	/* servname may be NULL */
michael@0: 
michael@0: 	if (servname == NULL)
michael@0: 		return 0;
michael@0: 	switch (ai->ai_family) {
michael@0: 	case AF_INET:
michael@0: #ifdef AF_INET6
michael@0: 	case AF_INET6:
michael@0: #endif
michael@0: 		break;
michael@0: 	default:
michael@0: 		return 0;
michael@0: 	}
michael@0: 
michael@0: 	switch (ai->ai_socktype) {
michael@0: 	case SOCK_RAW:
michael@0: 		return EAI_SERVICE;
michael@0: 	case SOCK_DGRAM:
michael@0: 	case SOCK_STREAM:
michael@0: 		allownumeric = 1;
michael@0: 		break;
michael@0: 	case ANY:
michael@0: #if 1  /* ANDROID-SPECIFIC CHANGE TO MATCH GLIBC */
michael@0: 		allownumeric = 1;
michael@0: #else
michael@0: 		allownumeric = 0;
michael@0: #endif
michael@0: 		break;
michael@0: 	default:
michael@0: 		return EAI_SOCKTYPE;
michael@0: 	}
michael@0: 
michael@0: 	port = str2number(servname);
michael@0: 	if (port >= 0) {
michael@0: 		if (!allownumeric)
michael@0: 			return EAI_SERVICE;
michael@0: 		if (port < 0 || port > 65535)
michael@0: 			return EAI_SERVICE;
michael@0: 		port = htons(port);
michael@0: 	} else {
michael@0: 		if (ai->ai_flags & AI_NUMERICSERV)
michael@0: 			return EAI_NONAME;
michael@0: 
michael@0: 		switch (ai->ai_socktype) {
michael@0: 		case SOCK_DGRAM:
michael@0: 			proto = "udp";
michael@0: 			break;
michael@0: 		case SOCK_STREAM:
michael@0: 			proto = "tcp";
michael@0: 			break;
michael@0: 		default:
michael@0: 			proto = NULL;
michael@0: 			break;
michael@0: 		}
michael@0: 
michael@0: 		if ((sp = getservbyname(servname, proto)) == NULL)
michael@0: 			return EAI_SERVICE;
michael@0: 		port = sp->s_port;
michael@0: 	}
michael@0: 
michael@0: 	if (!matchonly) {
michael@0: 		switch (ai->ai_family) {
michael@0: 		case AF_INET:
michael@0: 			((struct sockaddr_in *)(void *)
michael@0: 			    ai->ai_addr)->sin_port = port;
michael@0: 			break;
michael@0: #ifdef INET6
michael@0: 		case AF_INET6:
michael@0: 			((struct sockaddr_in6 *)(void *)
michael@0: 			    ai->ai_addr)->sin6_port = port;
michael@0: 			break;
michael@0: #endif
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	return 0;
michael@0: }
michael@0: 
michael@0: static const struct afd *
michael@0: find_afd(int af)
michael@0: {
michael@0: 	const struct afd *afd;
michael@0: 
michael@0: 	if (af == PF_UNSPEC)
michael@0: 		return NULL;
michael@0: 	for (afd = afdl; afd->a_af; afd++) {
michael@0: 		if (afd->a_af == af)
michael@0: 			return afd;
michael@0: 	}
michael@0: 	return NULL;
michael@0: }
michael@0: 
michael@0: #ifdef INET6
michael@0: /* convert a string to a scope identifier. XXX: IPv6 specific */
michael@0: static int
michael@0: ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
michael@0: {
michael@0: 	u_long lscopeid;
michael@0: 	struct in6_addr *a6;
michael@0: 	char *ep;
michael@0: 
michael@0: 	assert(scope != NULL);
michael@0: 	assert(sin6 != NULL);
michael@0: 	assert(scopeid != NULL);
michael@0: 
michael@0: 	a6 = &sin6->sin6_addr;
michael@0: 
michael@0: 	/* empty scopeid portion is invalid */
michael@0: 	if (*scope == '\0')
michael@0: 		return -1;
michael@0: 
michael@0: 	if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
michael@0: 		/*
michael@0: 		 * We currently assume a one-to-one mapping between links
michael@0: 		 * and interfaces, so we simply use interface indices for
michael@0: 		 * like-local scopes.
michael@0: 		 */
michael@0: 		*scopeid = if_nametoindex(scope);
michael@0: 		if (*scopeid == 0)
michael@0: 			goto trynumeric;
michael@0: 		return 0;
michael@0: 	}
michael@0: 
michael@0: 	/* still unclear about literal, allow numeric only - placeholder */
michael@0: 	if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
michael@0: 		goto trynumeric;
michael@0: 	if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
michael@0: 		goto trynumeric;
michael@0: 	else
michael@0: 		goto trynumeric;	/* global */
michael@0: 
michael@0: 	/* try to convert to a numeric id as a last resort */
michael@0:   trynumeric:
michael@0: 	errno = 0;
michael@0: 	lscopeid = strtoul(scope, &ep, 10);
michael@0: 	*scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
michael@0: 	if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
michael@0: 		return 0;
michael@0: 	else
michael@0: 		return -1;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: /* code duplicate with gethnamaddr.c */
michael@0: 
michael@0: static const char AskedForGot[] =
michael@0: 	"gethostby*.getanswer: asked for \"%s\", got \"%s\"";
michael@0: 
michael@0: static struct addrinfo *
michael@0: getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
michael@0:     const struct addrinfo *pai)
michael@0: {
michael@0: 	struct addrinfo sentinel, *cur;
michael@0: 	struct addrinfo ai;
michael@0: 	const struct afd *afd;
michael@0: 	char *canonname;
michael@0: 	const HEADER *hp;
michael@0: 	const u_char *cp;
michael@0: 	int n;
michael@0: 	const u_char *eom;
michael@0: 	char *bp, *ep;
michael@0: 	int type, class, ancount, qdcount;
michael@0: 	int haveanswer, had_error;
michael@0: 	char tbuf[MAXDNAME];
michael@0: 	int (*name_ok) (const char *);
michael@0: 	char hostbuf[8*1024];
michael@0: 
michael@0: 	assert(answer != NULL);
michael@0: 	assert(qname != NULL);
michael@0: 	assert(pai != NULL);
michael@0: 
michael@0: 	memset(&sentinel, 0, sizeof(sentinel));
michael@0: 	cur = &sentinel;
michael@0: 
michael@0: 	canonname = NULL;
michael@0: 	eom = answer->buf + anslen;
michael@0: 	switch (qtype) {
michael@0: 	case T_A:
michael@0: 	case T_AAAA:
michael@0: 	case T_ANY:	/*use T_ANY only for T_A/T_AAAA lookup*/
michael@0: 		name_ok = res_hnok;
michael@0: 		break;
michael@0: 	default:
michael@0: 		return NULL;	/* XXX should be abort(); */
michael@0: 	}
michael@0: 	/*
michael@0: 	 * find first satisfactory answer
michael@0: 	 */
michael@0: 	hp = &answer->hdr;
michael@0: 	ancount = ntohs(hp->ancount);
michael@0: 	qdcount = ntohs(hp->qdcount);
michael@0: 	bp = hostbuf;
michael@0: 	ep = hostbuf + sizeof hostbuf;
michael@0: 	cp = answer->buf + HFIXEDSZ;
michael@0: 	if (qdcount != 1) {
michael@0: 		h_errno = NO_RECOVERY;
michael@0: 		return (NULL);
michael@0: 	}
michael@0: 	n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
michael@0: 	if ((n < 0) || !(*name_ok)(bp)) {
michael@0: 		h_errno = NO_RECOVERY;
michael@0: 		return (NULL);
michael@0: 	}
michael@0: 	cp += n + QFIXEDSZ;
michael@0: 	if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
michael@0: 		/* res_send() has already verified that the query name is the
michael@0: 		 * same as the one we sent; this just gets the expanded name
michael@0: 		 * (i.e., with the succeeding search-domain tacked on).
michael@0: 		 */
michael@0: 		n = strlen(bp) + 1;		/* for the \0 */
michael@0: 		if (n >= MAXHOSTNAMELEN) {
michael@0: 			h_errno = NO_RECOVERY;
michael@0: 			return (NULL);
michael@0: 		}
michael@0: 		canonname = bp;
michael@0: 		bp += n;
michael@0: 		/* The qname can be abbreviated, but h_name is now absolute. */
michael@0: 		qname = canonname;
michael@0: 	}
michael@0: 	haveanswer = 0;
michael@0: 	had_error = 0;
michael@0: 	while (ancount-- > 0 && cp < eom && !had_error) {
michael@0: 		n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
michael@0: 		if ((n < 0) || !(*name_ok)(bp)) {
michael@0: 			had_error++;
michael@0: 			continue;
michael@0: 		}
michael@0: 		cp += n;			/* name */
michael@0: 		type = _getshort(cp);
michael@0:  		cp += INT16SZ;			/* type */
michael@0: 		class = _getshort(cp);
michael@0:  		cp += INT16SZ + INT32SZ;	/* class, TTL */
michael@0: 		n = _getshort(cp);
michael@0: 		cp += INT16SZ;			/* len */
michael@0: 		if (class != C_IN) {
michael@0: 			/* XXX - debug? syslog? */
michael@0: 			cp += n;
michael@0: 			continue;		/* XXX - had_error++ ? */
michael@0: 		}
michael@0: 		if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
michael@0: 		    type == T_CNAME) {
michael@0: 			n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
michael@0: 			if ((n < 0) || !(*name_ok)(tbuf)) {
michael@0: 				had_error++;
michael@0: 				continue;
michael@0: 			}
michael@0: 			cp += n;
michael@0: 			/* Get canonical name. */
michael@0: 			n = strlen(tbuf) + 1;	/* for the \0 */
michael@0: 			if (n > ep - bp || n >= MAXHOSTNAMELEN) {
michael@0: 				had_error++;
michael@0: 				continue;
michael@0: 			}
michael@0: 			strlcpy(bp, tbuf, (size_t)(ep - bp));
michael@0: 			canonname = bp;
michael@0: 			bp += n;
michael@0: 			continue;
michael@0: 		}
michael@0: 		if (qtype == T_ANY) {
michael@0: 			if (!(type == T_A || type == T_AAAA)) {
michael@0: 				cp += n;
michael@0: 				continue;
michael@0: 			}
michael@0: 		} else if (type != qtype) {
michael@0: 			if (type != T_KEY && type != T_SIG)
michael@0: 				syslog(LOG_NOTICE|LOG_AUTH,
michael@0: 	       "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
michael@0: 				       qname, p_class(C_IN), p_type(qtype),
michael@0: 				       p_type(type));
michael@0: 			cp += n;
michael@0: 			continue;		/* XXX - had_error++ ? */
michael@0: 		}
michael@0: 		switch (type) {
michael@0: 		case T_A:
michael@0: 		case T_AAAA:
michael@0: 			if (strcasecmp(canonname, bp) != 0) {
michael@0: 				syslog(LOG_NOTICE|LOG_AUTH,
michael@0: 				       AskedForGot, canonname, bp);
michael@0: 				cp += n;
michael@0: 				continue;	/* XXX - had_error++ ? */
michael@0: 			}
michael@0: 			if (type == T_A && n != INADDRSZ) {
michael@0: 				cp += n;
michael@0: 				continue;
michael@0: 			}
michael@0: 			if (type == T_AAAA && n != IN6ADDRSZ) {
michael@0: 				cp += n;
michael@0: 				continue;
michael@0: 			}
michael@0: 			if (type == T_AAAA) {
michael@0: 				struct in6_addr in6;
michael@0: 				memcpy(&in6, cp, IN6ADDRSZ);
michael@0: 				if (IN6_IS_ADDR_V4MAPPED(&in6)) {
michael@0: 					cp += n;
michael@0: 					continue;
michael@0: 				}
michael@0: 			}
michael@0: 			if (!haveanswer) {
michael@0: 				int nn;
michael@0: 
michael@0: 				canonname = bp;
michael@0: 				nn = strlen(bp) + 1;	/* for the \0 */
michael@0: 				bp += nn;
michael@0: 			}
michael@0: 
michael@0: 			/* don't overwrite pai */
michael@0: 			ai = *pai;
michael@0: 			ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
michael@0: 			afd = find_afd(ai.ai_family);
michael@0: 			if (afd == NULL) {
michael@0: 				cp += n;
michael@0: 				continue;
michael@0: 			}
michael@0: 			cur->ai_next = get_ai(&ai, afd, (const char *)cp);
michael@0: 			if (cur->ai_next == NULL)
michael@0: 				had_error++;
michael@0: 			while (cur && cur->ai_next)
michael@0: 				cur = cur->ai_next;
michael@0: 			cp += n;
michael@0: 			break;
michael@0: 		default:
michael@0: 			abort();
michael@0: 		}
michael@0: 		if (!had_error)
michael@0: 			haveanswer++;
michael@0: 	}
michael@0: 	if (haveanswer) {
michael@0: 		if (!canonname)
michael@0: 			(void)get_canonname(pai, sentinel.ai_next, qname);
michael@0: 		else
michael@0: 			(void)get_canonname(pai, sentinel.ai_next, canonname);
michael@0: 		h_errno = NETDB_SUCCESS;
michael@0: 		return sentinel.ai_next;
michael@0: 	}
michael@0: 
michael@0: 	h_errno = NO_RECOVERY;
michael@0: 	return NULL;
michael@0: }
michael@0: 
michael@0: struct addrinfo_sort_elem {
michael@0: 	struct addrinfo *ai;
michael@0: 	int has_src_addr;
michael@0: 	sockaddr_union src_addr;
michael@0: 	int original_order;
michael@0: };
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _get_scope(const struct sockaddr *addr)
michael@0: {
michael@0: 	if (addr->sa_family == AF_INET6) {
michael@0: 		const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr;
michael@0: 		if (IN6_IS_ADDR_MULTICAST(&addr6->sin6_addr)) {
michael@0: 			return IPV6_ADDR_MC_SCOPE(&addr6->sin6_addr);
michael@0: 		} else if (IN6_IS_ADDR_LOOPBACK(&addr6->sin6_addr) ||
michael@0: 			   IN6_IS_ADDR_LINKLOCAL(&addr6->sin6_addr)) {
michael@0: 			/*
michael@0: 			 * RFC 4291 section 2.5.3 says loopback is to be treated as having
michael@0: 			 * link-local scope.
michael@0: 			 */
michael@0: 			return IPV6_ADDR_SCOPE_LINKLOCAL;
michael@0: 		} else if (IN6_IS_ADDR_SITELOCAL(&addr6->sin6_addr)) {
michael@0: 			return IPV6_ADDR_SCOPE_SITELOCAL;
michael@0: 		} else {
michael@0: 			return IPV6_ADDR_SCOPE_GLOBAL;
michael@0: 		}
michael@0: 	} else if (addr->sa_family == AF_INET) {
michael@0: 		const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr;
michael@0: 		unsigned long int na = ntohl(addr4->sin_addr.s_addr);
michael@0: 
michael@0: 		if (IN_LOOPBACK(na) ||                          /* 127.0.0.0/8 */
michael@0: 		    (na & 0xffff0000) == 0xa9fe0000) {          /* 169.254.0.0/16 */
michael@0: 			return IPV6_ADDR_SCOPE_LINKLOCAL;
michael@0: 		} else {
michael@0: 			/*
michael@0: 			 * According to draft-ietf-6man-rfc3484-revise-01 section 2.3,
michael@0: 			 * it is best not to treat the private IPv4 ranges
michael@0: 			 * (10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16) as being
michael@0: 			 * in a special scope, so we don't.
michael@0: 			 */
michael@0: 			return IPV6_ADDR_SCOPE_GLOBAL;
michael@0: 		}
michael@0: 	} else {
michael@0: 		/*
michael@0: 		 * This should never happen.
michael@0: 		 * Return a scope with low priority as a last resort.
michael@0: 		 */
michael@0: 		return IPV6_ADDR_SCOPE_NODELOCAL;
michael@0: 	}
michael@0: }
michael@0: 
michael@0: /* These macros are modelled after the ones in <netinet/in6.h>. */
michael@0: 
michael@0: /* RFC 4380, section 2.6 */
michael@0: #define IN6_IS_ADDR_TEREDO(a)	 \
michael@0: 	((*(const uint32_t *)(const void *)(&(a)->s6_addr[0]) == ntohl(0x20010000)))
michael@0: 
michael@0: /* RFC 3056, section 2. */
michael@0: #define IN6_IS_ADDR_6TO4(a)	 \
michael@0: 	(((a)->s6_addr[0] == 0x20) && ((a)->s6_addr[1] == 0x02))
michael@0: 
michael@0: /* 6bone testing address area (3ffe::/16), deprecated in RFC 3701. */
michael@0: #define IN6_IS_ADDR_6BONE(a)      \
michael@0: 	(((a)->s6_addr[0] == 0x3f) && ((a)->s6_addr[1] == 0xfe))
michael@0: 
michael@0: /*
michael@0:  * Get the label for a given IPv4/IPv6 address.
michael@0:  * RFC 3484, section 2.1, plus changes from draft-ietf-6man-rfc3484-revise-01.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _get_label(const struct sockaddr *addr)
michael@0: {
michael@0: 	if (addr->sa_family == AF_INET) {
michael@0: 		return 3;
michael@0: 	} else if (addr->sa_family == AF_INET6) {
michael@0: 		const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr;
michael@0: 		if (IN6_IS_ADDR_LOOPBACK(&addr6->sin6_addr)) {
michael@0: 			return 0;
michael@0: 		} else if (IN6_IS_ADDR_V4MAPPED(&addr6->sin6_addr)) {
michael@0: 			return 3;
michael@0: 		} else if (IN6_IS_ADDR_6TO4(&addr6->sin6_addr)) {
michael@0: 			return 4;
michael@0: 		} else if (IN6_IS_ADDR_TEREDO(&addr6->sin6_addr)) {
michael@0: 			return 5;
michael@0: 		} else if (IN6_IS_ADDR_V4COMPAT(&addr6->sin6_addr)) {
michael@0: 			return 10;
michael@0: 		} else if (IN6_IS_ADDR_SITELOCAL(&addr6->sin6_addr)) {
michael@0: 			return 11;
michael@0: 		} else if (IN6_IS_ADDR_6BONE(&addr6->sin6_addr)) {
michael@0: 			return 12;
michael@0: 		} else {
michael@0: 			return 2;
michael@0: 		}
michael@0: 	} else {
michael@0: 		/*
michael@0: 		 * This should never happen.
michael@0: 		 * Return a semi-random label as a last resort.
michael@0: 		 */
michael@0: 		return 1;
michael@0: 	}
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Get the precedence for a given IPv4/IPv6 address.
michael@0:  * RFC 3484, section 2.1, plus changes from draft-ietf-6man-rfc3484-revise-01.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _get_precedence(const struct sockaddr *addr)
michael@0: {
michael@0: 	if (addr->sa_family == AF_INET) {
michael@0: 		return 30;
michael@0: 	} else if (addr->sa_family == AF_INET6) {
michael@0: 		const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr;
michael@0: 		if (IN6_IS_ADDR_LOOPBACK(&addr6->sin6_addr)) {
michael@0: 			return 60;
michael@0: 		} else if (IN6_IS_ADDR_V4MAPPED(&addr6->sin6_addr)) {
michael@0: 			return 30;
michael@0: 		} else if (IN6_IS_ADDR_6TO4(&addr6->sin6_addr)) {
michael@0: 			return 20;
michael@0: 		} else if (IN6_IS_ADDR_TEREDO(&addr6->sin6_addr)) {
michael@0: 			return 10;
michael@0: 		} else if (IN6_IS_ADDR_V4COMPAT(&addr6->sin6_addr) ||
michael@0: 		           IN6_IS_ADDR_SITELOCAL(&addr6->sin6_addr) ||
michael@0: 		           IN6_IS_ADDR_6BONE(&addr6->sin6_addr)) {
michael@0: 			return 1;
michael@0: 		} else {
michael@0: 			return 40;
michael@0: 		}
michael@0: 	} else {
michael@0: 		return 1;
michael@0: 	}
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Find number of matching initial bits between the two addresses a1 and a2.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _common_prefix_len(const struct in6_addr *a1, const struct in6_addr *a2)
michael@0: {
michael@0: 	const char *p1 = (const char *)a1;
michael@0: 	const char *p2 = (const char *)a2;
michael@0: 	unsigned i;
michael@0: 
michael@0: 	for (i = 0; i < sizeof(*a1); ++i) {
michael@0: 		int x, j;
michael@0: 
michael@0: 		if (p1[i] == p2[i]) {
michael@0: 			continue;
michael@0: 		}
michael@0: 		x = p1[i] ^ p2[i];
michael@0: 		for (j = 0; j < CHAR_BIT; ++j) {
michael@0: 			if (x & (1 << (CHAR_BIT - 1))) {
michael@0: 				return i * CHAR_BIT + j;
michael@0: 			}
michael@0: 			x <<= 1;
michael@0: 		}
michael@0: 	}
michael@0: 	return sizeof(*a1) * CHAR_BIT;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Compare two source/destination address pairs.
michael@0:  * RFC 3484, section 6.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _rfc3484_compare(const void *ptr1, const void* ptr2)
michael@0: {
michael@0: 	const struct addrinfo_sort_elem *a1 = (const struct addrinfo_sort_elem *)ptr1;
michael@0: 	const struct addrinfo_sort_elem *a2 = (const struct addrinfo_sort_elem *)ptr2;
michael@0: 	int scope_src1, scope_dst1, scope_match1;
michael@0: 	int scope_src2, scope_dst2, scope_match2;
michael@0: 	int label_src1, label_dst1, label_match1;
michael@0: 	int label_src2, label_dst2, label_match2;
michael@0: 	int precedence1, precedence2;
michael@0: 	int prefixlen1, prefixlen2;
michael@0: 
michael@0: 	/* Rule 1: Avoid unusable destinations. */
michael@0: 	if (a1->has_src_addr != a2->has_src_addr) {
michael@0: 		return a2->has_src_addr - a1->has_src_addr;
michael@0: 	}
michael@0: 
michael@0: 	/* Rule 2: Prefer matching scope. */
michael@0: 	scope_src1 = _get_scope(&a1->src_addr.generic);
michael@0: 	scope_dst1 = _get_scope(a1->ai->ai_addr);
michael@0: 	scope_match1 = (scope_src1 == scope_dst1);
michael@0: 
michael@0: 	scope_src2 = _get_scope(&a2->src_addr.generic);
michael@0: 	scope_dst2 = _get_scope(a2->ai->ai_addr);
michael@0: 	scope_match2 = (scope_src2 == scope_dst2);
michael@0: 
michael@0: 	if (scope_match1 != scope_match2) {
michael@0: 		return scope_match2 - scope_match1;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * Rule 3: Avoid deprecated addresses.
michael@0: 	 * TODO(sesse): We don't currently have a good way of finding this.
michael@0: 	 */
michael@0: 
michael@0: 	/*
michael@0: 	 * Rule 4: Prefer home addresses.
michael@0: 	 * TODO(sesse): We don't currently have a good way of finding this.
michael@0: 	 */
michael@0: 
michael@0: 	/* Rule 5: Prefer matching label. */
michael@0: 	label_src1 = _get_label(&a1->src_addr.generic);
michael@0: 	label_dst1 = _get_label(a1->ai->ai_addr);
michael@0: 	label_match1 = (label_src1 == label_dst1);
michael@0: 
michael@0: 	label_src2 = _get_label(&a2->src_addr.generic);
michael@0: 	label_dst2 = _get_label(a2->ai->ai_addr);
michael@0: 	label_match2 = (label_src2 == label_dst2);
michael@0: 
michael@0: 	if (label_match1 != label_match2) {
michael@0: 		return label_match2 - label_match1;
michael@0: 	}
michael@0: 
michael@0: 	/* Rule 6: Prefer higher precedence. */
michael@0: 	precedence1 = _get_precedence(a1->ai->ai_addr);
michael@0: 	precedence2 = _get_precedence(a2->ai->ai_addr);
michael@0: 	if (precedence1 != precedence2) {
michael@0: 		return precedence2 - precedence1;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * Rule 7: Prefer native transport.
michael@0: 	 * TODO(sesse): We don't currently have a good way of finding this.
michael@0: 	 */
michael@0: 
michael@0: 	/* Rule 8: Prefer smaller scope. */
michael@0: 	if (scope_dst1 != scope_dst2) {
michael@0: 		return scope_dst1 - scope_dst2;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * Rule 9: Use longest matching prefix.
michael@0:          * We implement this for IPv6 only, as the rules in RFC 3484 don't seem
michael@0:          * to work very well directly applied to IPv4. (glibc uses information from
michael@0:          * the routing table for a custom IPv4 implementation here.)
michael@0: 	 */
michael@0: 	if (a1->has_src_addr && a1->ai->ai_addr->sa_family == AF_INET6 &&
michael@0: 	    a2->has_src_addr && a2->ai->ai_addr->sa_family == AF_INET6) {
michael@0: 		const struct sockaddr_in6 *a1_src = &a1->src_addr.in6;
michael@0: 		const struct sockaddr_in6 *a1_dst = (const struct sockaddr_in6 *)a1->ai->ai_addr;
michael@0: 		const struct sockaddr_in6 *a2_src = &a2->src_addr.in6;
michael@0: 		const struct sockaddr_in6 *a2_dst = (const struct sockaddr_in6 *)a2->ai->ai_addr;
michael@0: 		prefixlen1 = _common_prefix_len(&a1_src->sin6_addr, &a1_dst->sin6_addr);
michael@0: 		prefixlen2 = _common_prefix_len(&a2_src->sin6_addr, &a2_dst->sin6_addr);
michael@0: 		if (prefixlen1 != prefixlen2) {
michael@0: 			return prefixlen2 - prefixlen1;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * Rule 10: Leave the order unchanged.
michael@0: 	 * We need this since qsort() is not necessarily stable.
michael@0: 	 */
michael@0: 	return a1->original_order - a2->original_order;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Find the source address that will be used if trying to connect to the given
michael@0:  * address. src_addr must be large enough to hold a struct sockaddr_in6.
michael@0:  *
michael@0:  * Returns 1 if a source address was found, 0 if the address is unreachable,
michael@0:  * and -1 if a fatal error occurred. If 0 or 1, the contents of src_addr are
michael@0:  * undefined.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _find_src_addr(const struct sockaddr *addr, struct sockaddr *src_addr)
michael@0: {
michael@0: 	int sock;
michael@0: 	int ret;
michael@0: 	socklen_t len;
michael@0: 
michael@0: 	switch (addr->sa_family) {
michael@0: 	case AF_INET:
michael@0: 		len = sizeof(struct sockaddr_in);
michael@0: 		break;
michael@0: 	case AF_INET6:
michael@0: 		len = sizeof(struct sockaddr_in6);
michael@0: 		break;
michael@0: 	default:
michael@0: 		/* No known usable source address for non-INET families. */
michael@0: 		return 0;
michael@0: 	}
michael@0: 
michael@0: 	sock = socket(addr->sa_family, SOCK_DGRAM, IPPROTO_UDP);
michael@0: 	if (sock == -1) {
michael@0: 		if (errno == EAFNOSUPPORT) {
michael@0: 			return 0;
michael@0: 		} else {
michael@0: 			return -1;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	do {
michael@0: 		ret = connect(sock, addr, len);
michael@0: 	} while (ret == -1 && errno == EINTR);
michael@0: 
michael@0: 	if (ret == -1) {
michael@0: 		close(sock);
michael@0: 		return 0;
michael@0: 	}
michael@0: 
michael@0: 	if (getsockname(sock, src_addr, &len) == -1) {
michael@0: 		close(sock);
michael@0: 		return -1;
michael@0: 	}
michael@0: 	close(sock);
michael@0: 	return 1;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Sort the linked list starting at sentinel->ai_next in RFC3484 order.
michael@0:  * Will leave the list unchanged if an error occurs.
michael@0:  */
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static void
michael@0: _rfc3484_sort(struct addrinfo *list_sentinel)
michael@0: {
michael@0: 	struct addrinfo *cur;
michael@0: 	int nelem = 0, i;
michael@0: 	struct addrinfo_sort_elem *elems;
michael@0: 
michael@0: 	cur = list_sentinel->ai_next;
michael@0: 	while (cur) {
michael@0: 		++nelem;
michael@0: 		cur = cur->ai_next;
michael@0: 	}
michael@0: 
michael@0: 	elems = (struct addrinfo_sort_elem *)malloc(nelem * sizeof(struct addrinfo_sort_elem));
michael@0: 	if (elems == NULL) {
michael@0: 		goto error;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * Convert the linked list to an array that also contains the candidate
michael@0: 	 * source address for each destination address.
michael@0: 	 */
michael@0: 	for (i = 0, cur = list_sentinel->ai_next; i < nelem; ++i, cur = cur->ai_next) {
michael@0: 		int has_src_addr;
michael@0: 		assert(cur != NULL);
michael@0: 		elems[i].ai = cur;
michael@0: 		elems[i].original_order = i;
michael@0: 
michael@0: 		has_src_addr = _find_src_addr(cur->ai_addr, &elems[i].src_addr.generic);
michael@0: 		if (has_src_addr == -1) {
michael@0: 			goto error;
michael@0: 		}
michael@0: 		elems[i].has_src_addr = has_src_addr;
michael@0: 	}
michael@0: 
michael@0: 	/* Sort the addresses, and rearrange the linked list so it matches the sorted order. */
michael@0: 	qsort((void *)elems, nelem, sizeof(struct addrinfo_sort_elem), _rfc3484_compare);
michael@0: 
michael@0: 	list_sentinel->ai_next = elems[0].ai;
michael@0: 	for (i = 0; i < nelem - 1; ++i) {
michael@0: 		elems[i].ai->ai_next = elems[i + 1].ai;
michael@0: 	}
michael@0: 	elems[nelem - 1].ai->ai_next = NULL;
michael@0: 
michael@0: error:
michael@0: 	free(elems);
michael@0: }
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _dns_getaddrinfo(void *rv, void	*cb_data, va_list ap)
michael@0: {
michael@0: 	struct addrinfo *ai;
michael@0: 	querybuf *buf, *buf2;
michael@0: 	const char *name;
michael@0: 	const struct addrinfo *pai;
michael@0: 	struct addrinfo sentinel, *cur;
michael@0: 	struct res_target q, q2;
michael@0: 	res_state res;
michael@0: 
michael@0: 	name = va_arg(ap, char *);
michael@0: 	pai = va_arg(ap, const struct addrinfo *);
michael@0: 	//fprintf(stderr, "_dns_getaddrinfo() name = '%s'\n", name);
michael@0: 
michael@0: 	memset(&q, 0, sizeof(q));
michael@0: 	memset(&q2, 0, sizeof(q2));
michael@0: 	memset(&sentinel, 0, sizeof(sentinel));
michael@0: 	cur = &sentinel;
michael@0: 
michael@0: 	buf = malloc(sizeof(*buf));
michael@0: 	if (buf == NULL) {
michael@0: 		h_errno = NETDB_INTERNAL;
michael@0: 		return NS_NOTFOUND;
michael@0: 	}
michael@0: 	buf2 = malloc(sizeof(*buf2));
michael@0: 	if (buf2 == NULL) {
michael@0: 		free(buf);
michael@0: 		h_errno = NETDB_INTERNAL;
michael@0: 		return NS_NOTFOUND;
michael@0: 	}
michael@0: 
michael@0: 	switch (pai->ai_family) {
michael@0: 	case AF_UNSPEC:
michael@0: 		/* prefer IPv6 */
michael@0: 		q.name = name;
michael@0: 		q.qclass = C_IN;
michael@0: 		q.answer = buf->buf;
michael@0: 		q.anslen = sizeof(buf->buf);
michael@0: 		int query_ipv6 = 1, query_ipv4 = 1;
michael@0: 		if (pai->ai_flags & AI_ADDRCONFIG) {
michael@0: 			query_ipv6 = _have_ipv6();
michael@0: 			query_ipv4 = _have_ipv4();
michael@0: 		}
michael@0: 		if (query_ipv6) {
michael@0: 			q.qtype = T_AAAA;
michael@0: 			if (query_ipv4) {
michael@0: 				q.next = &q2;
michael@0: 				q2.name = name;
michael@0: 				q2.qclass = C_IN;
michael@0: 				q2.qtype = T_A;
michael@0: 				q2.answer = buf2->buf;
michael@0: 				q2.anslen = sizeof(buf2->buf);
michael@0: 			}
michael@0: 		} else if (query_ipv4) {
michael@0: 			q.qtype = T_A;
michael@0: 		} else {
michael@0: 			free(buf);
michael@0: 			free(buf2);
michael@0: 			return NS_NOTFOUND;
michael@0: 		}
michael@0: 		break;
michael@0: 	case AF_INET:
michael@0: 		q.name = name;
michael@0: 		q.qclass = C_IN;
michael@0: 		q.qtype = T_A;
michael@0: 		q.answer = buf->buf;
michael@0: 		q.anslen = sizeof(buf->buf);
michael@0: 		break;
michael@0: 	case AF_INET6:
michael@0: 		q.name = name;
michael@0: 		q.qclass = C_IN;
michael@0: 		q.qtype = T_AAAA;
michael@0: 		q.answer = buf->buf;
michael@0: 		q.anslen = sizeof(buf->buf);
michael@0: 		break;
michael@0: 	default:
michael@0: 		free(buf);
michael@0: 		free(buf2);
michael@0: 		return NS_UNAVAIL;
michael@0: 	}
michael@0: 
michael@0: 	res = __res_get_state();
michael@0: 	if (res == NULL) {
michael@0: 		free(buf);
michael@0: 		free(buf2);
michael@0: 		return NS_NOTFOUND;
michael@0: 	}
michael@0: 
michael@0: 	if (res_searchN(name, &q, res) < 0) {
michael@0: 		__res_put_state(res);
michael@0: 		free(buf);
michael@0: 		free(buf2);
michael@0: 		return NS_NOTFOUND;
michael@0: 	}
michael@0: 	ai = getanswer(buf, q.n, q.name, q.qtype, pai);
michael@0: 	if (ai) {
michael@0: 		cur->ai_next = ai;
michael@0: 		while (cur && cur->ai_next)
michael@0: 			cur = cur->ai_next;
michael@0: 	}
michael@0: 	if (q.next) {
michael@0: 		ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai);
michael@0: 		if (ai)
michael@0: 			cur->ai_next = ai;
michael@0: 	}
michael@0: 	free(buf);
michael@0: 	free(buf2);
michael@0: 	if (sentinel.ai_next == NULL) {
michael@0: 		__res_put_state(res);
michael@0: 		switch (h_errno) {
michael@0: 		case HOST_NOT_FOUND:
michael@0: 			return NS_NOTFOUND;
michael@0: 		case TRY_AGAIN:
michael@0: 			return NS_TRYAGAIN;
michael@0: 		default:
michael@0: 			return NS_UNAVAIL;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	_rfc3484_sort(&sentinel);
michael@0: 
michael@0: 	__res_put_state(res);
michael@0: 
michael@0: 	*((struct addrinfo **)rv) = sentinel.ai_next;
michael@0: 	return NS_SUCCESS;
michael@0: }
michael@0: 
michael@0: static void
michael@0: _sethtent(_pseudo_FILE * __restrict__ hostf)
michael@0: {
michael@0: 	assert(hostf);
michael@0: 	if (hostf->mapping == MAP_FAILED)
michael@0: 		(void) _pseudo_fopen_r(hostf, _PATH_HOSTS);
michael@0: 	else
michael@0: 		_pseudo_rewind(hostf);
michael@0: }
michael@0: 
michael@0: static void
michael@0: _endhtent(_pseudo_FILE * __restrict__ hostf)
michael@0: {
michael@0: 	assert(hostf);
michael@0: 	(void) _pseudo_fclose(hostf);
michael@0: }
michael@0: 
michael@0: static struct addrinfo *
michael@0: _gethtent(_pseudo_FILE * __restrict__ hostf, const char *name, const struct addrinfo *pai)
michael@0: {
michael@0: 	char *p;
michael@0: 	char *cp, *tname, *cname;
michael@0: 	struct addrinfo hints, *res0, *res;
michael@0: 	int error;
michael@0: 	const char *addr;
michael@0: 	char hostbuf[8*1024];
michael@0: 
michael@0: 	assert(hostf);
michael@0: //	fprintf(stderr, "_gethtent() name = '%s'\n", name);
michael@0: 	assert(name != NULL);
michael@0: 	assert(pai != NULL);
michael@0: 
michael@0: 	if (hostf->mapping == MAP_FAILED)
michael@0: 		(void) _pseudo_fopen_r(hostf, _PATH_HOSTS);
michael@0: 	if (hostf->mapping == MAP_FAILED)
michael@0: 		return (NULL);
michael@0:  again:
michael@0: 	if (!(p = _pseudo_fgets(hostbuf, sizeof hostbuf, hostf)))
michael@0: 		return (NULL);
michael@0: 	if (*p == '#')
michael@0: 		goto again;
michael@0: 	if (!(cp = strpbrk(p, "#\n")))
michael@0: 		goto again;
michael@0: 	*cp = '\0';
michael@0: 	if (!(cp = strpbrk(p, " \t")))
michael@0: 		goto again;
michael@0: 	*cp++ = '\0';
michael@0: 	addr = p;
michael@0: 	/* if this is not something we're looking for, skip it. */
michael@0: 	cname = NULL;
michael@0: 	while (cp && *cp) {
michael@0: 		if (*cp == ' ' || *cp == '\t') {
michael@0: 			cp++;
michael@0: 			continue;
michael@0: 		}
michael@0: 		if (!cname)
michael@0: 			cname = cp;
michael@0: 		tname = cp;
michael@0: 		if ((cp = strpbrk(cp, " \t")) != NULL)
michael@0: 			*cp++ = '\0';
michael@0: //		fprintf(stderr, "\ttname = '%s'", tname);
michael@0: 		if (strcasecmp(name, tname) == 0)
michael@0: 			goto found;
michael@0: 	}
michael@0: 	goto again;
michael@0: 
michael@0: found:
michael@0: 	hints = *pai;
michael@0: 	hints.ai_flags = AI_NUMERICHOST;
michael@0: 	error = __wrap_getaddrinfo(addr, NULL, &hints, &res0);
michael@0: 	if (error)
michael@0: 		goto again;
michael@0: 	for (res = res0; res; res = res->ai_next) {
michael@0: 		/* cover it up */
michael@0: 		res->ai_flags = pai->ai_flags;
michael@0: 
michael@0: 		if (pai->ai_flags & AI_CANONNAME) {
michael@0: 			if (get_canonname(pai, res, cname) != 0) {
michael@0: 				__wrap_freeaddrinfo(res0);
michael@0: 				goto again;
michael@0: 			}
michael@0: 		}
michael@0: 	}
michael@0: 	return res0;
michael@0: }
michael@0: 
michael@0: /*ARGSUSED*/
michael@0: static int
michael@0: _files_getaddrinfo(void *rv, void *cb_data, va_list ap)
michael@0: {
michael@0: 	const char *name;
michael@0: 	const struct addrinfo *pai;
michael@0: 	struct addrinfo sentinel, *cur;
michael@0: 	struct addrinfo *p;
michael@0: 	_pseudo_FILE hostf = _PSEUDO_FILE_INITIALIZER;
michael@0: 
michael@0: 	name = va_arg(ap, char *);
michael@0: 	pai = va_arg(ap, struct addrinfo *);
michael@0: 
michael@0: //	fprintf(stderr, "_files_getaddrinfo() name = '%s'\n", name);
michael@0: 	memset(&sentinel, 0, sizeof(sentinel));
michael@0: 	cur = &sentinel;
michael@0: 
michael@0: 	_sethtent(&hostf);
michael@0: 	while ((p = _gethtent(&hostf, name, pai)) != NULL) {
michael@0: 		cur->ai_next = p;
michael@0: 		while (cur && cur->ai_next)
michael@0: 			cur = cur->ai_next;
michael@0: 	}
michael@0: 	_endhtent(&hostf);
michael@0: 
michael@0: 	*((struct addrinfo **)rv) = sentinel.ai_next;
michael@0: 	if (sentinel.ai_next == NULL)
michael@0: 		return NS_NOTFOUND;
michael@0: 	return NS_SUCCESS;
michael@0: }
michael@0: 
michael@0: /* resolver logic */
michael@0: 
michael@0: /*
michael@0:  * Formulate a normal query, send, and await answer.
michael@0:  * Returned answer is placed in supplied buffer "answer".
michael@0:  * Perform preliminary check of answer, returning success only
michael@0:  * if no error is indicated and the answer count is nonzero.
michael@0:  * Return the size of the response on success, -1 on error.
michael@0:  * Error number is left in h_errno.
michael@0:  *
michael@0:  * Caller must parse answer and determine whether it answers the question.
michael@0:  */
michael@0: static int
michael@0: res_queryN(const char *name, /* domain name */ struct res_target *target,
michael@0:     res_state res)
michael@0: {
michael@0: 	u_char buf[MAXPACKET];
michael@0: 	HEADER *hp;
michael@0: 	int n;
michael@0: 	struct res_target *t;
michael@0: 	int rcode;
michael@0: 	int ancount;
michael@0: 
michael@0: 	assert(name != NULL);
michael@0: 	/* XXX: target may be NULL??? */
michael@0: 
michael@0: 	rcode = NOERROR;
michael@0: 	ancount = 0;
michael@0: 
michael@0: 	for (t = target; t; t = t->next) {
michael@0: 		int class, type;
michael@0: 		u_char *answer;
michael@0: 		int anslen;
michael@0: 
michael@0: 		hp = (HEADER *)(void *)t->answer;
michael@0: 		hp->rcode = NOERROR;	/* default */
michael@0: 
michael@0: 		/* make it easier... */
michael@0: 		class = t->qclass;
michael@0: 		type = t->qtype;
michael@0: 		answer = t->answer;
michael@0: 		anslen = t->anslen;
michael@0: #ifdef DEBUG
michael@0: 		if (res->options & RES_DEBUG)
michael@0: 			printf(";; res_nquery(%s, %d, %d)\n", name, class, type);
michael@0: #endif
michael@0: 
michael@0: 		n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL,
michael@0: 		    buf, sizeof(buf));
michael@0: #ifdef RES_USE_EDNS0
michael@0: 		if (n > 0 && (res->options & RES_USE_EDNS0) != 0)
michael@0: 			n = res_nopt(res, n, buf, sizeof(buf), anslen);
michael@0: #endif
michael@0: 		if (n <= 0) {
michael@0: #ifdef DEBUG
michael@0: 			if (res->options & RES_DEBUG)
michael@0: 				printf(";; res_nquery: mkquery failed\n");
michael@0: #endif
michael@0: 			h_errno = NO_RECOVERY;
michael@0: 			return n;
michael@0: 		}
michael@0: 		n = res_nsend(res, buf, n, answer, anslen);
michael@0: #if 0
michael@0: 		if (n < 0) {
michael@0: #ifdef DEBUG
michael@0: 			if (res->options & RES_DEBUG)
michael@0: 				printf(";; res_query: send error\n");
michael@0: #endif
michael@0: 			h_errno = TRY_AGAIN;
michael@0: 			return n;
michael@0: 		}
michael@0: #endif
michael@0: 
michael@0: 		if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
michael@0: 			rcode = hp->rcode;	/* record most recent error */
michael@0: #ifdef DEBUG
michael@0: 			if (res->options & RES_DEBUG)
michael@0: 				printf(";; rcode = %u, ancount=%u\n", hp->rcode,
michael@0: 				    ntohs(hp->ancount));
michael@0: #endif
michael@0: 			continue;
michael@0: 		}
michael@0: 
michael@0: 		ancount += ntohs(hp->ancount);
michael@0: 
michael@0: 		t->n = n;
michael@0: 	}
michael@0: 
michael@0: 	if (ancount == 0) {
michael@0: 		switch (rcode) {
michael@0: 		case NXDOMAIN:
michael@0: 			h_errno = HOST_NOT_FOUND;
michael@0: 			break;
michael@0: 		case SERVFAIL:
michael@0: 			h_errno = TRY_AGAIN;
michael@0: 			break;
michael@0: 		case NOERROR:
michael@0: 			h_errno = NO_DATA;
michael@0: 			break;
michael@0: 		case FORMERR:
michael@0: 		case NOTIMP:
michael@0: 		case REFUSED:
michael@0: 		default:
michael@0: 			h_errno = NO_RECOVERY;
michael@0: 			break;
michael@0: 		}
michael@0: 		return -1;
michael@0: 	}
michael@0: 	return ancount;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Formulate a normal query, send, and retrieve answer in supplied buffer.
michael@0:  * Return the size of the response on success, -1 on error.
michael@0:  * If enabled, implement search rules until answer or unrecoverable failure
michael@0:  * is detected.  Error code, if any, is left in h_errno.
michael@0:  */
michael@0: static int
michael@0: res_searchN(const char *name, struct res_target *target, res_state res)
michael@0: {
michael@0: 	const char *cp, * const *domain;
michael@0: 	HEADER *hp;
michael@0: 	u_int dots;
michael@0: 	int trailing_dot, ret, saved_herrno;
michael@0: 	int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
michael@0: 
michael@0: 	assert(name != NULL);
michael@0: 	assert(target != NULL);
michael@0: 
michael@0: 	hp = (HEADER *)(void *)target->answer;	/*XXX*/
michael@0: 
michael@0: 	errno = 0;
michael@0: 	h_errno = HOST_NOT_FOUND;	/* default, if we never query */
michael@0: 	dots = 0;
michael@0: 	for (cp = name; *cp; cp++)
michael@0: 		dots += (*cp == '.');
michael@0: 	trailing_dot = 0;
michael@0: 	if (cp > name && *--cp == '.')
michael@0: 		trailing_dot++;
michael@0: 
michael@0: 
michael@0:         //fprintf(stderr, "res_searchN() name = '%s'\n", name);
michael@0: 
michael@0: 	/*
michael@0: 	 * if there aren't any dots, it could be a user-level alias
michael@0: 	 */
michael@0: 	if (!dots && (cp = __hostalias(name)) != NULL) {
michael@0: 		ret = res_queryN(cp, target, res);
michael@0: 		return ret;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * If there are dots in the name already, let's just give it a try
michael@0: 	 * 'as is'.  The threshold can be set with the "ndots" option.
michael@0: 	 */
michael@0: 	saved_herrno = -1;
michael@0: 	if (dots >= res->ndots) {
michael@0: 		ret = res_querydomainN(name, NULL, target, res);
michael@0: 		if (ret > 0)
michael@0: 			return (ret);
michael@0: 		saved_herrno = h_errno;
michael@0: 		tried_as_is++;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * We do at least one level of search if
michael@0: 	 *	- there is no dot and RES_DEFNAME is set, or
michael@0: 	 *	- there is at least one dot, there is no trailing dot,
michael@0: 	 *	  and RES_DNSRCH is set.
michael@0: 	 */
michael@0: 	if ((!dots && (res->options & RES_DEFNAMES)) ||
michael@0: 	    (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
michael@0: 		int done = 0;
michael@0: 
michael@0: 		for (domain = (const char * const *)res->dnsrch;
michael@0: 		   *domain && !done;
michael@0: 		   domain++) {
michael@0: 
michael@0: 			ret = res_querydomainN(name, *domain, target, res);
michael@0: 			if (ret > 0)
michael@0: 				return ret;
michael@0: 
michael@0: 			/*
michael@0: 			 * If no server present, give up.
michael@0: 			 * If name isn't found in this domain,
michael@0: 			 * keep trying higher domains in the search list
michael@0: 			 * (if that's enabled).
michael@0: 			 * On a NO_DATA error, keep trying, otherwise
michael@0: 			 * a wildcard entry of another type could keep us
michael@0: 			 * from finding this entry higher in the domain.
michael@0: 			 * If we get some other error (negative answer or
michael@0: 			 * server failure), then stop searching up,
michael@0: 			 * but try the input name below in case it's
michael@0: 			 * fully-qualified.
michael@0: 			 */
michael@0: 			if (errno == ECONNREFUSED) {
michael@0: 				h_errno = TRY_AGAIN;
michael@0: 				return -1;
michael@0: 			}
michael@0: 
michael@0: 			switch (h_errno) {
michael@0: 			case NO_DATA:
michael@0: 				got_nodata++;
michael@0: 				/* FALLTHROUGH */
michael@0: 			case HOST_NOT_FOUND:
michael@0: 				/* keep trying */
michael@0: 				break;
michael@0: 			case TRY_AGAIN:
michael@0: 				if (hp->rcode == SERVFAIL) {
michael@0: 					/* try next search element, if any */
michael@0: 					got_servfail++;
michael@0: 					break;
michael@0: 				}
michael@0: 				/* FALLTHROUGH */
michael@0: 			default:
michael@0: 				/* anything else implies that we're done */
michael@0: 				done++;
michael@0: 			}
michael@0: 			/*
michael@0: 			 * if we got here for some reason other than DNSRCH,
michael@0: 			 * we only wanted one iteration of the loop, so stop.
michael@0: 			 */
michael@0: 			if (!(res->options & RES_DNSRCH))
michael@0: 			        done++;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * if we have not already tried the name "as is", do that now.
michael@0: 	 * note that we do this regardless of how many dots were in the
michael@0: 	 * name or whether it ends with a dot.
michael@0: 	 */
michael@0: 	if (!tried_as_is) {
michael@0: 		ret = res_querydomainN(name, NULL, target, res);
michael@0: 		if (ret > 0)
michael@0: 			return ret;
michael@0: 	}
michael@0: 
michael@0: 	/*
michael@0: 	 * if we got here, we didn't satisfy the search.
michael@0: 	 * if we did an initial full query, return that query's h_errno
michael@0: 	 * (note that we wouldn't be here if that query had succeeded).
michael@0: 	 * else if we ever got a nodata, send that back as the reason.
michael@0: 	 * else send back meaningless h_errno, that being the one from
michael@0: 	 * the last DNSRCH we did.
michael@0: 	 */
michael@0: 	if (saved_herrno != -1)
michael@0: 		h_errno = saved_herrno;
michael@0: 	else if (got_nodata)
michael@0: 		h_errno = NO_DATA;
michael@0: 	else if (got_servfail)
michael@0: 		h_errno = TRY_AGAIN;
michael@0: 	return -1;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Perform a call on res_query on the concatenation of name and domain,
michael@0:  * removing a trailing dot from name if domain is NULL.
michael@0:  */
michael@0: static int
michael@0: res_querydomainN(const char *name, const char *domain,
michael@0:     struct res_target *target, res_state res)
michael@0: {
michael@0: 	char nbuf[MAXDNAME];
michael@0: 	const char *longname = nbuf;
michael@0: 	size_t n, d;
michael@0: 
michael@0: 	assert(name != NULL);
michael@0: 	/* XXX: target may be NULL??? */
michael@0: 
michael@0: #ifdef DEBUG
michael@0: 	if (res->options & RES_DEBUG)
michael@0: 		printf(";; res_querydomain(%s, %s)\n",
michael@0: 			name, domain?domain:"<Nil>");
michael@0: #endif
michael@0: 	if (domain == NULL) {
michael@0: 		/*
michael@0: 		 * Check for trailing '.';
michael@0: 		 * copy without '.' if present.
michael@0: 		 */
michael@0: 		n = strlen(name);
michael@0: 		if (n + 1 > sizeof(nbuf)) {
michael@0: 			h_errno = NO_RECOVERY;
michael@0: 			return -1;
michael@0: 		}
michael@0: 		if (n > 0 && name[--n] == '.') {
michael@0: 			strncpy(nbuf, name, n);
michael@0: 			nbuf[n] = '\0';
michael@0: 		} else
michael@0: 			longname = name;
michael@0: 	} else {
michael@0: 		n = strlen(name);
michael@0: 		d = strlen(domain);
michael@0: 		if (n + 1 + d + 1 > sizeof(nbuf)) {
michael@0: 			h_errno = NO_RECOVERY;
michael@0: 			return -1;
michael@0: 		}
michael@0: 		snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
michael@0: 	}
michael@0: 	return res_queryN(longname, target, res);
michael@0: }