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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* Copyright (C) 2004 by the Massachusetts Institute of Technology,
* Cambridge, MA, USA. All Rights Reserved.
*
* This software is being provided to you, the LICENSEE, by the
* Massachusetts Institute of Technology (M.I.T.) under the following
* license. By obtaining, using and/or copying this software, you agree
* that you have read, understood, and will comply with these terms and
* conditions:
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify and distribute
* this software and its documentation for any purpose and without fee or
* royalty is hereby granted, provided that you agree to comply with the
* following copyright notice and statements, including the disclaimer, and
* that the same appear on ALL copies of the software and documentation,
* including modifications that you make for internal use or for
* distribution:
*
* THIS SOFTWARE IS PROVIDED "AS IS", AND M.I.T. MAKES NO REPRESENTATIONS
* OR WARRANTIES, EXPRESS OR IMPLIED. By way of example, but not
* limitation, M.I.T. MAKES NO REPRESENTATIONS OR WARRANTIES OF
* MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF
* THE LICENSED SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY THIRD PARTY
* PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS.
*
* The name of the Massachusetts Institute of Technology or M.I.T. may NOT
* be used in advertising or publicity pertaining to distribution of the
* software. Title to copyright in this software and any associated
* documentation shall at all times remain with M.I.T., and USER agrees to
* preserve same.
*
* Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
*/
/*
* Approach overview:
*
* If a system version is available but buggy, save handles to it,
* redefine the names to refer to static functions defined here, and
* in those functions, call the system versions and fix up the
* returned data. Use the native data structures and flag values.
*
* If no system version exists, use gethostby* and fake it. Define
* the data structures and flag values locally.
*
*
* On Mac OS X, getaddrinfo results aren't cached (though
* gethostbyname results are), so we need to build a cache here. Now
* things are getting really messy. Because the cache is in use, we
* use getservbyname, and throw away thread safety. (Not that the
* cache is thread safe, but when we get locking support, that'll be
* dealt with.) This code needs tearing down and rebuilding, soon.
*
*
* Note that recent Windows developers' code has an interesting hack:
* When you include the right header files, with the right set of
* macros indicating system versions, you'll get an inline function
* that looks for getaddrinfo (or whatever) in the system library, and
* calls it if it's there. If it's not there, it fakes it with
* gethostby* calls.
*
* We're taking a simpler approach: A system provides these routines or
* it does not.
*
* Someday, we may want to take into account different versions (say,
* different revs of GNU libc) where some are broken in one way, and
* some work or are broken in another way. Cross that bridge when we
* come to it.
*/
/* To do, maybe:
*
* + For AIX 4.3.3, using the RFC 2133 definition: Implement
* AI_NUMERICHOST. It's not defined in the header file.
*
* For certain (old?) versions of GNU libc, AI_NUMERICHOST is
* defined but not implemented.
*
* + Use gethostbyname2, inet_aton and other IPv6 or thread-safe
* functions if available. But, see
* http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=135182 for one
* gethostbyname2 problem on Linux. And besides, if a platform is
* supporting IPv6 at all, they really should be doing getaddrinfo
* by now.
*
* + inet_ntop, inet_pton
*
* + Conditionally export/import the function definitions, so a
* library can have a single copy instead of multiple.
*
* + Upgrade host requirements to include working implementations of
* these functions, and throw all this away. Pleeease? :-)
*/
#include "port-sockets.h"
#include "socket-utils.h"
#include "k5-platform.h"
#include "k5-thread.h"
#include "fake-addrinfo.h"
#if defined (__APPLE__) && defined (__MACH__) && 0
#define FAI_CACHE
#endif
struct face {
struct in_addr *addrs4;
struct in6_addr *addrs6;
unsigned int naddrs4, naddrs6;
time_t expiration;
char *canonname, *name;
struct face *next;
};
/* fake addrinfo cache */
struct fac {
k5_mutex_t lock;
struct face *data;
};
extern struct fac krb5int_fac;
extern int krb5int_init_fac (void);
extern void krb5int_fini_fac (void);
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