1 /*****************************************************************************
2 * getaddrinfo.c: getaddrinfo/getnameinfo replacement functions
3 *****************************************************************************
4 * Copyright (C) 2005 the VideoLAN team
5 * Copyright (C) 2002-2004 Rémi Denis-Courmont
8 * Author: Rémi Denis-Courmont <rem # videolan.org>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
27 #include <stddef.h> /* size_t */
28 #include <string.h> /* strlen(), memcpy(), memset(), strchr() */
29 #include <stdlib.h> /* malloc(), free(), strtoul() */
32 #ifdef HAVE_SYS_TYPES_H
33 # include <sys/types.h>
35 #ifdef HAVE_ARPA_INET_H
36 # include <arpa/inet.h>
38 #ifdef HAVE_NETINET_IN_H
39 # include <netinet/in.h>
45 #include <vlc_network.h>
48 # define NO_ADDRESS NO_DATA
51 # define INADDR_NONE 0xFFFFFFFF
57 #define _NI_MASK (NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|\
59 #define _AI_MASK (AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST)
62 #ifndef HAVE_GAI_STRERROR
67 } const __gai_errlist[] =
70 { EAI_BADFLAGS, "Invalid flag used" },
71 { EAI_NONAME, "Host or service not found" },
72 { EAI_AGAIN, "Temporary name service failure" },
73 { EAI_FAIL, "Non-recoverable name service failure" },
74 { EAI_NODATA, "No data for host name" },
75 { EAI_FAMILY, "Unsupported address family" },
76 { EAI_SOCKTYPE, "Unsupported socket type" },
77 { EAI_SERVICE, "Incompatible service for socket type" },
78 { EAI_ADDRFAMILY, "Unavailable address family for host name" },
79 { EAI_MEMORY, "Memory allocation failure" },
80 { EAI_SYSTEM, "System error" },
84 static const char *__gai_unknownerr = "Unrecognized error number";
86 /****************************************************************************
87 * Converts an EAI_* error code into human readable english text.
88 ****************************************************************************/
89 const char *vlc_gai_strerror( int errnum )
93 for (i = 0; __gai_errlist[i].msg != NULL; i++)
94 if (errnum == __gai_errlist[i].code)
95 return __gai_errlist[i].msg;
97 return __gai_unknownerr;
99 # undef _EAI_POSITIVE_MAX
100 #else /* ifndef HAVE_GAI_STRERROR */
101 const char *vlc_gai_strerror( int errnum )
103 return gai_strerror( errnum );
107 #if !(defined (HAVE_GETNAMEINFO) && defined (HAVE_GETADDRINFO))
109 * Converts the current herrno error value into an EAI_* error code.
110 * That error code is normally returned by getnameinfo() or getaddrinfo().
113 gai_error_from_herrno( void )
121 # if (NO_ADDRESS != NO_DATA)
134 #endif /* if !(HAVE_GETNAMEINFO && HAVE_GETADDRINFO) */
136 #ifndef HAVE_GETNAMEINFO
138 * getnameinfo() non-thread-safe IPv4-only implementation,
139 * Address-family-independant address to hostname translation
140 * (reverse DNS lookup in case of IPv4).
142 * This is meant for use on old IP-enabled systems that are not IPv6-aware,
143 * and probably do not have getnameinfo(), but have the old gethostbyaddr()
146 * GNU C library 2.0.x is known to lack this function, even though it defines
150 __getnameinfo( const struct sockaddr *sa, socklen_t salen,
151 char *host, int hostlen, char *serv, int servlen, int flags )
153 if (((unsigned)salen < sizeof (struct sockaddr_in))
154 || (sa->sa_family != AF_INET))
156 else if (flags & (~_NI_MASK))
160 const struct sockaddr_in *addr;
162 addr = (const struct sockaddr_in *)sa;
168 /* host name resolution */
169 if (!(flags & NI_NUMERICHOST))
171 struct hostent *hent;
173 hent = gethostbyaddr ((const void*)&addr->sin_addr,
178 strlcpy (host, hent->h_name, hostlen);
181 * only keep first part of hostname
182 * if user don't want fully qualified
185 if (flags & NI_NOFQDN)
189 ptr = strchr (host, '.');
196 else if (flags & NI_NAMEREQD)
197 return gai_error_from_herrno ();
201 /* inet_ntoa() can't fail */
202 strlcpy (host, inet_ntoa (addr->sin_addr), hostlen);
207 snprintf (serv, servlen, "%u",
208 (unsigned int)ntohs (addr->sin_port));
209 serv[servlen - 1] = '\0';
215 #endif /* if !HAVE_GETNAMEINFO */
217 #if defined( WIN32 ) && !defined( UNDER_CE )
219 * Here is the kind of kludge you need to keep binary compatibility among
220 * varying OS versions...
222 typedef int (CALLBACK * GETNAMEINFO) ( const struct sockaddr*, socklen_t,
223 char*, DWORD, char*, DWORD, int );
224 typedef int (CALLBACK * GETADDRINFO) (const char *, const char *,
225 const struct addrinfo *,
228 typedef void (CALLBACK * FREEADDRINFO) ( struct addrinfo * );
231 static WINAPI int _ws2_getnameinfo_bind( const struct sockaddr *sa, socklen_t salen,
232 char *host, DWORD hostlen, char *serv, DWORD servlen, int flags );
234 static WINAPI int _ws2_getaddrinfo_bind(const char *node, const char *service,
235 const struct addrinfo *hints, struct addrinfo **res);
237 static WINAPI void _ws2_freeaddrinfo_bind( struct addrinfo *infos );
239 static GETNAMEINFO ws2_getnameinfo = _ws2_getnameinfo_bind;
240 static GETADDRINFO ws2_getaddrinfo = _ws2_getaddrinfo_bind;
241 static FREEADDRINFO ws2_freeaddrinfo = _ws2_freeaddrinfo_bind;
243 static int _ws2_find_ipv6_api(void)
245 /* For Windows XP and above, IPv6 stack is in WS2_32.DLL */
246 HINSTANCE module = LoadLibrary( "ws2_32.dll" );
249 ws2_getnameinfo = (GETNAMEINFO)GetProcAddress( module, "getnameinfo" );
250 ws2_getaddrinfo = (GETADDRINFO)GetProcAddress( module, "getaddrinfo" );
251 ws2_freeaddrinfo = (FREEADDRINFO)GetProcAddress( module, "freeaddrinfo" );
252 if( ws2_getnameinfo && ws2_getaddrinfo && ws2_freeaddrinfo )
257 FreeLibrary( module );
259 /* For Windows 2000 and below, try IPv6 stack in in WSHIP6.DLL */
260 module = LoadLibrary( "wship6.dll" );
263 ws2_getnameinfo = (GETNAMEINFO)GetProcAddress( module, "getnameinfo" );
264 ws2_getaddrinfo = (GETADDRINFO)GetProcAddress( module, "getaddrinfo" );
265 ws2_freeaddrinfo = (FREEADDRINFO)GetProcAddress( module, "freeaddrinfo" );
266 if( ws2_getnameinfo && ws2_getaddrinfo && ws2_freeaddrinfo )
271 FreeLibrary( module );
278 static WINAPI int _ws2_getnameinfo_bind( const struct sockaddr *sa, socklen_t salen,
279 char *host, DWORD hostlen, char *serv, DWORD servlen, int flags )
281 if( _ws2_find_ipv6_api() )
283 return ws2_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
285 /* return a possible error if API is not found */
286 WSASetLastError(WSAHOST_NOT_FOUND);
287 return WSAHOST_NOT_FOUND;
290 static WINAPI int _ws2_getaddrinfo_bind(const char *node, const char *service,
291 const struct addrinfo *hints, struct addrinfo **res)
293 if( _ws2_find_ipv6_api() )
295 return ws2_getaddrinfo(node, service, hints, res);
297 /* return a possible error if API is not found */
298 WSASetLastError(WSAHOST_NOT_FOUND);
299 return WSAHOST_NOT_FOUND;
302 static WINAPI void _ws2_freeaddrinfo_bind( struct addrinfo *infos )
304 if( _ws2_find_ipv6_api() )
306 ws2_freeaddrinfo(infos);
312 #ifndef HAVE_GETADDRINFO
314 * This functions must be used to free the memory allocated by getaddrinfo().
317 __freeaddrinfo (struct addrinfo *res)
321 if (res->ai_canonname != NULL)
322 free (res->ai_canonname);
323 if (res->ai_addr != NULL)
325 if (res->ai_next != NULL)
333 * Internal function that builds an addrinfo struct.
335 static struct addrinfo *
336 makeaddrinfo (int af, int type, int proto,
337 const struct sockaddr *addr, size_t addrlen,
338 const char *canonname)
340 struct addrinfo *res;
342 res = (struct addrinfo *)malloc (sizeof (struct addrinfo));
347 res->ai_socktype = type;
348 res->ai_protocol = proto;
349 res->ai_addrlen = addrlen;
350 res->ai_addr = malloc (addrlen);
351 res->ai_canonname = NULL;
354 if (res->ai_addr != NULL)
356 memcpy (res->ai_addr, addr, addrlen);
358 if (canonname != NULL)
360 res->ai_canonname = strdup (canonname);
361 if (res->ai_canonname != NULL)
362 return res; /* success ! */
369 vlc_freeaddrinfo (res);
374 static struct addrinfo *
375 makeipv4info (int type, int proto, u_long ip, u_short port, const char *name)
377 struct sockaddr_in addr;
379 memset (&addr, 0, sizeof (addr));
380 addr.sin_family = AF_INET;
382 addr.sin_len = sizeof (addr);
384 addr.sin_port = port;
385 addr.sin_addr.s_addr = ip;
387 return makeaddrinfo (AF_INET, type, proto,
388 (struct sockaddr*)&addr, sizeof (addr), name);
393 * getaddrinfo() non-thread-safe IPv4-only implementation
394 * Address-family-independant hostname to address resolution.
396 * This is meant for IPv6-unaware systems that do probably not provide
397 * getaddrinfo(), but still have old function gethostbyname().
399 * Only UDP and TCP over IPv4 are supported here.
402 __getaddrinfo (const char *node, const char *service,
403 const struct addrinfo *hints, struct addrinfo **res)
405 struct addrinfo *info;
408 int protocol = 0, flags = 0;
409 const char *name = NULL;
413 * Maybe you knew already that Winsock does not handle TCP/RST packets
414 * properly, so that when a TCP connection fails, it will wait until it
415 * times out even if the remote host did return a TCP/RST. However, it
416 * still sees the TCP/RST as the error code is 10061 instead of 10060.
417 * Basically, we have the stupid brainfucked behavior with DNS queries...
418 * When the recursive DNS server returns an error, Winsock waits about
419 * 2 seconds before it returns to the callers, even though it should know
420 * that is pointless. I'd like to know how come this hasn't been fixed
421 * for the past decade, or maybe not.
423 * Anyway, this is causing a severe delay when the SAP listener tries
424 * to resolve more than ten IPv6 numeric addresses. Modern systems will
425 * eventually realize that it is an IPv6 address, and won't try to resolve
426 * it as a IPv4 address via the Domain Name Service. Old systems
427 * (including Windows XP without the IPv6 stack) will not. It is normally
428 * not an issue as the DNS server usually returns an error very quickly.
429 * But it IS a severe issue on Windows, given the bug explained above.
430 * So here comes one more bug-to-bug Windows compatibility fix.
432 if ((node != NULL) && (strchr (node, ':') != NULL))
438 flags = hints->ai_flags;
440 if (flags & ~_AI_MASK)
442 /* only accept AF_INET and AF_UNSPEC */
443 if (hints->ai_family && (hints->ai_family != AF_INET))
446 /* protocol sanity check */
447 switch (hints->ai_socktype)
450 protocol = IPPROTO_TCP;
454 protocol = IPPROTO_UDP;
466 if (hints->ai_protocol && protocol
467 && (protocol != hints->ai_protocol))
476 if (flags & AI_PASSIVE)
477 ip = htonl (INADDR_ANY);
479 ip = htonl (INADDR_LOOPBACK);
482 if ((ip = inet_addr (node)) == INADDR_NONE)
484 struct hostent *entry = NULL;
486 /* hostname resolution */
487 if (!(flags & AI_NUMERICHOST))
488 entry = gethostbyname (node);
493 if ((entry->h_length != 4) || (entry->h_addrtype != AF_INET))
496 ip = *((u_long *) entry->h_addr);
497 if (flags & AI_CANONNAME)
498 name = entry->h_name;
501 if ((flags & AI_CANONNAME) && (name == NULL))
504 /* service resolution */
512 d = strtoul (service, &end, 0);
513 if (end[0] /* service is not a number */
516 struct servent *entry;
517 const char *protoname;
533 entry = getservbyname (service, protoname);
537 port = entry->s_port;
540 port = htons ((u_short)d);
543 /* building results... */
544 if ((!protocol) || (protocol == IPPROTO_UDP))
546 info = makeipv4info (SOCK_DGRAM, IPPROTO_UDP, ip, port, name);
552 if (flags & AI_PASSIVE)
553 info->ai_flags |= AI_PASSIVE;
556 if ((!protocol) || (protocol == IPPROTO_TCP))
558 info = makeipv4info (SOCK_STREAM, IPPROTO_TCP, ip, port, name);
564 info->ai_next = *res;
565 if (flags & AI_PASSIVE)
566 info->ai_flags |= AI_PASSIVE;
572 #endif /* if !HAVE_GETADDRINFO */
575 int vlc_getnameinfo( const struct sockaddr *sa, int salen,
576 char *host, int hostlen, int *portnum, int flags )
578 char psz_servbuf[6], *psz_serv;
579 int i_servlen, i_val;
581 flags |= NI_NUMERICSERV;
582 if( portnum != NULL )
584 psz_serv = psz_servbuf;
585 i_servlen = sizeof( psz_servbuf );
592 #if defined( WIN32 ) && !defined( UNDER_CE )
593 i_val = ws2_getnameinfo( sa, salen, host, hostlen, psz_serv,
596 #if defined( HAVE_GETNAMEINFO ) || defined( UNDER_CE )
597 i_val = getnameinfo(sa, salen, host, hostlen, psz_serv, i_servlen, flags);
600 # ifdef HAVE_USABLE_MUTEX_THAT_DONT_NEED_LIBVLC_POINTER
601 static vlc_value_t lock;
603 /* my getnameinfo implementation is not thread-safe as it uses
604 * gethostbyaddr and the likes */
605 vlc_mutex_lock( lock.p_address );
607 # warning FIXME : This is not thread-safe!
609 i_val = __getnameinfo( sa, salen, host, hostlen, psz_serv, i_servlen,
611 # ifdef HAVE_USABLE_MUTEX_THAT_DONT_NEED_LIBVLC_POINTER
612 vlc_mutex_unlock( lock.p_address );
617 if( portnum != NULL )
618 *portnum = atoi( psz_serv );
624 /* TODO: support for setting sin6_scope_id */
625 int vlc_getaddrinfo( vlc_object_t *p_this, const char *node,
626 int i_port, const struct addrinfo *p_hints,
627 struct addrinfo **res )
629 struct addrinfo hints;
630 char psz_buf[NI_MAXHOST], *psz_node, psz_service[6];
633 * In VLC, we always use port number as integer rather than strings
634 * for historical reasons (and portability).
636 if( ( i_port > 65535 ) || ( i_port < 0 ) )
638 msg_Err( p_this, "invalid port number %d specified", i_port );
642 /* cannot overflow */
643 snprintf( psz_service, 6, "%d", i_port );
645 /* Check if we have to force ipv4 or ipv6 */
646 if( p_hints == NULL )
647 memset( &hints, 0, sizeof( hints ) );
649 memcpy( &hints, p_hints, sizeof( hints ) );
651 if( hints.ai_family == AF_UNSPEC )
655 var_Create( p_this, "ipv4", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
656 var_Get( p_this, "ipv4", &val );
658 hints.ai_family = AF_INET;
661 var_Create( p_this, "ipv6", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
662 var_Get( p_this, "ipv6", &val );
664 hints.ai_family = AF_INET6;
670 * - accept "" as NULL
671 * - ignore square brackets
673 if( ( node == NULL ) || (node[0] == '\0' ) )
679 strlcpy( psz_buf, node, NI_MAXHOST );
683 if( psz_buf[0] == '[' )
687 ptr = strrchr( psz_buf, ']' );
688 if( ( ptr != NULL ) && (ptr[1] == '\0' ) )
696 #if defined( WIN32 ) && !defined( UNDER_CE )
698 * Winsock tries to resolve numerical IPv4 addresses as AAAA
699 * and IPv6 addresses as A... There comes the work around.
701 if ((hints.ai_flags & AI_NUMERICHOST) == 0)
703 hints.ai_flags |= AI_NUMERICHOST;
705 if (ws2_getaddrinfo (psz_node, psz_service, &hints, res) == 0)
708 hints.ai_flags &= ~AI_NUMERICHOST;
711 return ws2_getaddrinfo (psz_node, psz_service, &hints, res);
713 #if defined( HAVE_GETADDRINFO ) || defined( UNDER_CE )
715 /* Run-time I18n Domain Names support */
717 static vlc_bool_t i_idn = VLC_TRUE; /* beware of thread-safety */
723 hints.ai_flags |= AI_IDN;
724 i_ret = getaddrinfo( psz_node, psz_service, &hints, res );
726 if( i_ret != EAI_BADFLAGS )
729 /* libidn not available: disable and retry without it */
731 /* NOTE: Using i_idn here would not be thread-safe */
732 hints.ai_flags &= ~AI_IDN;
734 msg_Dbg( p_this, "International Domain Names not supported - " \
739 return getaddrinfo( psz_node, psz_service, &hints, res );
746 var_Create( p_this->p_libvlc, "getaddrinfo_mutex", VLC_VAR_MUTEX );
747 var_Get( p_this->p_libvlc, "getaddrinfo_mutex", &lock );
748 vlc_mutex_lock( lock.p_address );
750 i_ret = __getaddrinfo( psz_node, psz_service, &hints, res );
751 vlc_mutex_unlock( lock.p_address );
758 void vlc_freeaddrinfo( struct addrinfo *infos )
760 #if defined( WIN32 ) && !defined( UNDER_CE )
761 ws2_freeaddrinfo( infos );
763 #if defined( HAVE_GETADDRINFO ) || defined( UNDER_CE )
764 freeaddrinfo( infos );
766 __freeaddrinfo( infos );