1 /*****************************************************************************
2 * getaddrinfo.c: getaddrinfo/getnameinfo replacement functions
3 *****************************************************************************
4 * Copyright (C) 2005 the VideoLAN team
5 * Copyright (C) 2002-2007 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
58 #ifndef HAVE_GAI_STRERROR
63 } const __gai_errlist[] =
66 { EAI_BADFLAGS, "Invalid flag used" },
67 { EAI_NONAME, "Host or service not found" },
68 { EAI_AGAIN, "Temporary name service failure" },
69 { EAI_FAIL, "Non-recoverable name service failure" },
70 { EAI_NODATA, "No data for host name" },
71 { EAI_FAMILY, "Unsupported address family" },
72 { EAI_SOCKTYPE, "Unsupported socket type" },
73 { EAI_SERVICE, "Incompatible service for socket type" },
74 { EAI_ADDRFAMILY, "Unavailable address family for host name" },
75 { EAI_MEMORY, "Memory allocation failure" },
76 { EAI_OVERFLOW, "Buffer overflow" },
77 { EAI_SYSTEM, "System error" },
81 static const char *__gai_unknownerr = "Unrecognized error number";
83 /****************************************************************************
84 * Converts an EAI_* error code into human readable english text.
85 ****************************************************************************/
86 const char *vlc_gai_strerror (int errnum)
88 for (unsigned i = 0; __gai_errlist[i].msg != NULL; i++)
89 if (errnum == __gai_errlist[i].code)
90 return __gai_errlist[i].msg;
92 return __gai_unknownerr;
94 #else /* ifndef HAVE_GAI_STRERROR */
95 const char *vlc_gai_strerror (int errnum)
97 return gai_strerror (errnum);
101 #ifndef HAVE_GETNAMEINFO
102 #define _NI_MASK (NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|\
105 * getnameinfo() non-thread-safe IPv4-only implementation,
106 * Address-family-independant address to hostname translation
107 * (reverse DNS lookup in case of IPv4).
109 * This is meant for use on old IP-enabled systems that are not IPv6-aware,
110 * and probably do not have getnameinfo(), but have the old gethostbyaddr()
113 * GNU C library 2.0.x is known to lack this function, even though it defines
117 getnameinfo (const struct sockaddr *sa, socklen_t salen,
118 char *host, int hostlen, char *serv, int servlen, int flags)
120 if (((size_t)salen < sizeof (struct sockaddr_in))
121 || (sa->sa_family != AF_INET))
123 else if (flags & (~_NI_MASK))
127 const struct sockaddr_in *addr;
129 addr = (const struct sockaddr_in *)sa;
133 /* host name resolution */
134 if (!(flags & NI_NUMERICHOST))
136 if (flags & NI_NAMEREQD)
140 /* inet_ntoa() is not thread-safe, do not use it */
141 uint32_t ipv4 = ntohl (addr->sin_addr.s_addr);
143 if (snprintf (host, hostlen, "%u.%u.%u.%u", ipv4 >> 24,
144 (ipv4 >> 16) & 0xff, (ipv4 >> 8) & 0xff,
145 ipv4 & 0xff) >= hostlen)
151 if (snprintf (serv, servlen, "%u",
152 (unsigned int)ntohs (addr->sin_port)) >= servlen)
159 #endif /* if !HAVE_GETNAMEINFO */
161 #ifndef HAVE_GETADDRINFO
162 #define _AI_MASK (AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST)
164 * Converts the current herrno error value into an EAI_* error code.
165 * That error code is normally returned by getnameinfo() or getaddrinfo().
168 gai_error_from_herrno (void)
176 # if (NO_ADDRESS != NO_DATA)
191 * This functions must be used to free the memory allocated by getaddrinfo().
193 static void freeaddrinfo (struct addrinfo *res)
197 if (res->ai_canonname != NULL)
198 free (res->ai_canonname);
199 if (res->ai_addr != NULL)
201 if (res->ai_next != NULL)
209 * Internal function that builds an addrinfo struct.
211 static struct addrinfo *
212 makeaddrinfo (int af, int type, int proto,
213 const struct sockaddr *addr, size_t addrlen,
214 const char *canonname)
216 struct addrinfo *res;
218 res = (struct addrinfo *)malloc (sizeof (struct addrinfo));
223 res->ai_socktype = type;
224 res->ai_protocol = proto;
225 res->ai_addrlen = addrlen;
226 res->ai_addr = malloc (addrlen);
227 res->ai_canonname = NULL;
230 if (res->ai_addr != NULL)
232 memcpy (res->ai_addr, addr, addrlen);
234 if (canonname != NULL)
236 res->ai_canonname = strdup (canonname);
237 if (res->ai_canonname != NULL)
238 return res; /* success ! */
245 vlc_freeaddrinfo (res);
250 static struct addrinfo *
251 makeipv4info (int type, int proto, u_long ip, u_short port, const char *name)
253 struct sockaddr_in addr;
255 memset (&addr, 0, sizeof (addr));
256 addr.sin_family = AF_INET;
258 addr.sin_len = sizeof (addr);
260 addr.sin_port = port;
261 addr.sin_addr.s_addr = ip;
263 return makeaddrinfo (AF_INET, type, proto,
264 (struct sockaddr*)&addr, sizeof (addr), name);
269 * getaddrinfo() non-thread-safe IPv4-only implementation
270 * Address-family-independant hostname to address resolution.
272 * This is meant for IPv6-unaware systems that do probably not provide
273 * getaddrinfo(), but still have old function gethostbyname().
275 * Only UDP and TCP over IPv4 are supported here.
278 getaddrinfo (const char *node, const char *service,
279 const struct addrinfo *hints, struct addrinfo **res)
281 struct addrinfo *info;
284 int protocol = 0, flags = 0;
285 const char *name = NULL;
289 * Maybe you knew already that Winsock does not handle TCP/RST packets
290 * properly, so that when a TCP connection fails, it will wait until it
291 * times out even if the remote host did return a TCP/RST. However, it
292 * still sees the TCP/RST as the error code is 10061 instead of 10060.
293 * Basically, we have the stupid brainfucked behavior with DNS queries...
294 * When the recursive DNS server returns an error, Winsock waits about
295 * 2 seconds before it returns to the callers, even though it should know
296 * that is pointless. I'd like to know how come this hasn't been fixed
297 * for the past decade, or maybe not.
299 * Anyway, this is causing a severe delay when the SAP listener tries
300 * to resolve more than ten IPv6 numeric addresses. Modern systems will
301 * eventually realize that it is an IPv6 address, and won't try to resolve
302 * it as a IPv4 address via the Domain Name Service. Old systems
303 * (including Windows XP without the IPv6 stack) will not. It is normally
304 * not an issue as the DNS server usually returns an error very quickly.
305 * But it IS a severe issue on Windows, given the bug explained above.
306 * So here comes one more bug-to-bug Windows compatibility fix.
308 if ((node != NULL) && (strchr (node, ':') != NULL))
314 flags = hints->ai_flags;
316 if (flags & ~_AI_MASK)
318 /* only accept AF_INET and AF_UNSPEC */
319 if (hints->ai_family && (hints->ai_family != AF_INET))
322 /* protocol sanity check */
323 switch (hints->ai_socktype)
326 protocol = IPPROTO_TCP;
330 protocol = IPPROTO_UDP;
342 if (hints->ai_protocol && protocol
343 && (protocol != hints->ai_protocol))
352 if (flags & AI_PASSIVE)
353 ip = htonl (INADDR_ANY);
355 ip = htonl (INADDR_LOOPBACK);
358 if ((ip = inet_addr (node)) == INADDR_NONE)
360 struct hostent *entry = NULL;
362 /* hostname resolution */
363 if (!(flags & AI_NUMERICHOST))
364 entry = gethostbyname (node);
367 return gai_error_from_herrno ();
369 if ((entry->h_length != 4) || (entry->h_addrtype != AF_INET))
372 ip = *((u_long *) entry->h_addr);
373 if (flags & AI_CANONNAME)
374 name = entry->h_name;
377 if ((flags & AI_CANONNAME) && (name == NULL))
380 /* service resolution */
388 d = strtoul (service, &end, 0);
389 if (end[0] /* service is not a number */
392 struct servent *entry;
393 const char *protoname;
409 entry = getservbyname (service, protoname);
413 port = entry->s_port;
416 port = htons ((u_short)d);
419 /* building results... */
420 if ((!protocol) || (protocol == IPPROTO_UDP))
422 info = makeipv4info (SOCK_DGRAM, IPPROTO_UDP, ip, port, name);
428 if (flags & AI_PASSIVE)
429 info->ai_flags |= AI_PASSIVE;
432 if ((!protocol) || (protocol == IPPROTO_TCP))
434 info = makeipv4info (SOCK_STREAM, IPPROTO_TCP, ip, port, name);
440 info->ai_next = *res;
441 if (flags & AI_PASSIVE)
442 info->ai_flags |= AI_PASSIVE;
448 #endif /* if !HAVE_GETADDRINFO */
450 #if defined( WIN32 ) && !defined( UNDER_CE )
452 * Here is the kind of kludge you need to keep binary compatibility among
453 * varying OS versions...
455 typedef int (WSAAPI * GETNAMEINFO) ( const struct sockaddr FAR *, socklen_t,
456 char FAR *, DWORD, char FAR *, DWORD, int );
457 typedef int (WSAAPI * GETADDRINFO) (const char FAR *, const char FAR *,
458 const struct addrinfo FAR *,
459 struct addrinfo FAR * FAR *);
461 typedef void (WSAAPI * FREEADDRINFO) ( struct addrinfo FAR * );
463 static int WSAAPI _ws2_getnameinfo_bind ( const struct sockaddr FAR *, socklen_t,
464 char FAR *, DWORD, char FAR *, DWORD, int );
465 static int WSAAPI _ws2_getaddrinfo_bind (const char FAR *, const char FAR *,
466 const struct addrinfo FAR *,
467 struct addrinfo FAR * FAR *);
469 static GETNAMEINFO ws2_getnameinfo = _ws2_getnameinfo_bind;
470 static GETADDRINFO ws2_getaddrinfo = _ws2_getaddrinfo_bind;
471 static FREEADDRINFO ws2_freeaddrinfo;
473 static FARPROC ws2_find_api (LPCTSTR name)
477 HMODULE m = GetModuleHandle (TEXT("WS2_32"));
479 f = GetProcAddress (m, name);
483 /* Windows 2K IPv6 preview */
484 m = LoadLibrary (TEXT("WSHIP6"));
486 f = GetProcAddress (m, name);
492 static WSAAPI int _ws2_getnameinfo_bind( const struct sockaddr FAR * sa, socklen_t salen,
493 char FAR *host, DWORD hostlen, char FAR *serv, DWORD servlen, int flags )
495 GETNAMEINFO entry = (GETNAMEINFO)ws2_find_api (TEXT("getnameinfo"));
498 /* call API before replacing function pointer to avoid crash */
499 int result = entry (sa, salen, host, hostlen, serv, servlen, flags);
500 ws2_getnameinfo = entry;
503 return getnameinfo (sa, salen, host, hostlen, serv, servlen, flags);
506 #define getnameinfo ws2_getnameinfo
508 /* So much for using different calling conventions */
509 static WSAAPI void call_freeaddrinfo (struct addrinfo *infos)
511 freeaddrinfo (infos);
514 static WSAAPI int _ws2_getaddrinfo_bind(const char FAR *node, const char FAR *service,
515 const struct addrinfo FAR *hints, struct addrinfo FAR * FAR *res)
518 FREEADDRINFO freentry;
520 entry = (GETADDRINFO)ws2_find_api (TEXT("getaddrinfo"));
521 freentry = (FREEADDRINFO)ws2_find_api (TEXT("freeaddrinfo"));
523 if ((entry != NULL) && (freentry != NULL))
525 /* call API before replacing function pointer to avoid crash */
526 int result = entry (node, service, hints, res);
527 ws2_freeaddrinfo = freentry;
528 ws2_getaddrinfo = entry;
531 ws2_freeaddrinfo = call_freeaddrinfo;
532 return getaddrinfo (node, service, hints, res);
536 #define getaddrinfo ws2_getaddrinfo
537 #define freeaddrinfo ws2_freeaddrinfo
538 #define HAVE_GETADDRINFO
543 int vlc_getnameinfo( const struct sockaddr *sa, int salen,
544 char *host, int hostlen, int *portnum, int flags )
546 char psz_servbuf[6], *psz_serv;
547 int i_servlen, i_val;
549 flags |= NI_NUMERICSERV;
550 if( portnum != NULL )
552 psz_serv = psz_servbuf;
553 i_servlen = sizeof( psz_servbuf );
561 i_val = getnameinfo(sa, salen, host, hostlen, psz_serv, i_servlen, flags);
563 if( portnum != NULL )
564 *portnum = atoi( psz_serv );
570 int vlc_getaddrinfo( vlc_object_t *p_this, const char *node,
571 int i_port, const struct addrinfo *p_hints,
572 struct addrinfo **res )
574 struct addrinfo hints;
575 char psz_buf[NI_MAXHOST], *psz_node, psz_service[6];
578 * In VLC, we always use port number as integer rather than strings
579 * for historical reasons (and portability).
581 if( ( i_port > 65535 ) || ( i_port < 0 ) )
583 msg_Err( p_this, "invalid port number %d specified", i_port );
587 /* cannot overflow */
588 snprintf( psz_service, 6, "%d", i_port );
590 /* Check if we have to force ipv4 or ipv6 */
591 memset (&hints, 0, sizeof (hints));
594 hints.ai_family = p_hints->ai_family;
595 hints.ai_socktype = p_hints->ai_socktype;
596 hints.ai_protocol = p_hints->ai_protocol;
597 hints.ai_flags = p_hints->ai_flags & (AI_NUMERICHOST|AI_PASSIVE|AI_CANONNAME);
599 #ifdef AI_NUMERICSERV
600 /* we only ever use port *numbers* */
601 hints.ai_flags |= AI_NUMERICSERV;
604 if( hints.ai_family == AF_UNSPEC )
608 var_Create( p_this, "ipv4", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
609 var_Get( p_this, "ipv4", &val );
611 hints.ai_family = AF_INET;
614 var_Create( p_this, "ipv6", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
615 var_Get( p_this, "ipv6", &val );
617 hints.ai_family = AF_INET6;
623 * - accept "" as NULL
624 * - ignore square brackets
626 if( ( node == NULL ) || (node[0] == '\0' ) )
632 strlcpy( psz_buf, node, NI_MAXHOST );
636 if( psz_buf[0] == '[' )
640 ptr = strrchr( psz_buf, ']' );
641 if( ( ptr != NULL ) && (ptr[1] == '\0' ) )
651 * Winsock tries to resolve numerical IPv4 addresses as AAAA
652 * and IPv6 addresses as A... There comes the bug-to-bug fix.
654 if ((hints.ai_flags & AI_NUMERICHOST) == 0)
656 hints.ai_flags |= AI_NUMERICHOST;
658 if (getaddrinfo (psz_node, psz_service, &hints, res) == 0)
661 hints.ai_flags &= ~AI_NUMERICHOST;
664 #if defined (HAVE_GETADDRINFO)
666 /* Run-time I18n Domain Names support */
667 static vlc_bool_t b_idn = VLC_TRUE; /* beware of thread-safety */
671 hints.ai_flags |= AI_IDN;
672 int ret = getaddrinfo (psz_node, psz_service, &hints, res);
674 if (ret != EAI_BADFLAGS)
677 /* IDN not available: disable and retry without it */
678 hints.ai_flags &= ~AI_IDN;
680 msg_Info (p_this, "International Domain Names not supported");
683 return getaddrinfo (psz_node, psz_service, &hints, res);
688 var_Create (p_this->p_libvlc, "getaddrinfo_mutex", VLC_VAR_MUTEX);
689 var_Get (p_this->p_libvlc, "getaddrinfo_mutex", &lock);
690 vlc_mutex_lock (lock.p_address);
692 ret = getaddrinfo (psz_node, psz_service, &hints, res);
693 vlc_mutex_unlock (lock.p_address);
699 void vlc_freeaddrinfo( struct addrinfo *infos )
701 freeaddrinfo (infos);