[c52d922] | 1 | #include "port_before.h" |
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| 2 | |
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| 3 | /* $NetBSD: nsdispatch.c,v 1.9 1999/01/25 00:16:17 lukem Exp $ */ |
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| 4 | |
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| 5 | /*- |
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| 6 | * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc. |
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| 7 | * All rights reserved. |
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| 8 | * |
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| 9 | * This code is derived from software contributed to The NetBSD Foundation |
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| 10 | * by Luke Mewburn. |
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| 11 | * |
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| 12 | * Redistribution and use in source and binary forms, with or without |
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| 13 | * modification, are permitted provided that the following conditions |
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| 14 | * are met: |
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| 15 | * 1. Redistributions of source code must retain the above copyright |
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| 16 | * notice, this list of conditions and the following disclaimer. |
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| 17 | * 2. Redistributions in binary form must reproduce the above copyright |
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| 18 | * notice, this list of conditions and the following disclaimer in the |
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| 19 | * documentation and/or other materials provided with the distribution. |
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| 20 | * 3. All advertising materials mentioning features or use of this software |
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| 21 | * must display the following acknowledgement: |
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| 22 | * This product includes software developed by the NetBSD |
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| 23 | * Foundation, Inc. and its contributors. |
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| 24 | * 4. Neither the name of The NetBSD Foundation nor the names of its |
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| 25 | * contributors may be used to endorse or promote products derived |
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| 26 | * from this software without specific prior written permission. |
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| 27 | * |
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| 28 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
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| 29 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
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| 30 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
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| 31 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
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| 32 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
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| 33 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
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| 34 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
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| 35 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
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| 36 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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| 37 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
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| 38 | * POSSIBILITY OF SUCH DAMAGE. |
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| 39 | */ |
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| 40 | /*- |
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| 41 | * Copyright (c) 2003 Networks Associates Technology, Inc. |
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| 42 | * All rights reserved. |
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| 43 | * |
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| 44 | * Portions of this software were developed for the FreeBSD Project by |
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| 45 | * Jacques A. Vidrine, Safeport Network Services, and Network |
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| 46 | * Associates Laboratories, the Security Research Division of Network |
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| 47 | * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 |
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| 48 | * ("CBOSS"), as part of the DARPA CHATS research program. |
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| 49 | * |
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| 50 | * Redistribution and use in source and binary forms, with or without |
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| 51 | * modification, are permitted provided that the following conditions |
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| 52 | * are met: |
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| 53 | * 1. Redistributions of source code must retain the above copyright |
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| 54 | * notice, this list of conditions and the following disclaimer. |
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| 55 | * 2. Redistributions in binary form must reproduce the above copyright |
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| 56 | * notice, this list of conditions and the following disclaimer in the |
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| 57 | * documentation and/or other materials provided with the distribution. |
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| 58 | * |
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| 59 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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| 60 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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| 61 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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| 62 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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| 63 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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| 64 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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| 65 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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| 66 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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| 67 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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| 68 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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| 69 | * SUCH DAMAGE. |
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| 70 | * |
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| 71 | */ |
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| 72 | #include <sys/cdefs.h> |
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| 73 | __FBSDID("$FreeBSD$"); |
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| 74 | |
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| 75 | #include "namespace.h" |
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| 76 | #include <sys/param.h> |
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| 77 | #include <sys/stat.h> |
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| 78 | |
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| 79 | #ifndef __rtems__ |
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| 80 | #include <dlfcn.h> |
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| 81 | #else |
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| 82 | #include <stdint.h> |
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| 83 | #endif |
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| 84 | #include <errno.h> |
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| 85 | #include <fcntl.h> |
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| 86 | #define _NS_PRIVATE |
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| 87 | #include <nsswitch.h> |
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| 88 | #include <pthread.h> |
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| 89 | #include <pthread_np.h> |
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| 90 | #include <stdio.h> |
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| 91 | #include <stdlib.h> |
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| 92 | #include <string.h> |
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| 93 | #include <syslog.h> |
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| 94 | #include <unistd.h> |
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| 95 | #include "un-namespace.h" |
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| 96 | #include "nss_tls.h" |
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| 97 | #include "libc_private.h" |
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| 98 | #ifdef NS_CACHING |
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| 99 | #include "nscache.h" |
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| 100 | #endif |
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| 101 | |
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| 102 | enum _nss_constants { |
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| 103 | /* Number of elements allocated when we grow a vector */ |
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| 104 | ELEMSPERCHUNK = 8 |
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| 105 | }; |
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| 106 | |
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| 107 | /* |
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| 108 | * Global NSS data structures are mostly read-only, but we update |
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| 109 | * them when we read or re-read the nsswitch.conf. |
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| 110 | */ |
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| 111 | static pthread_rwlock_t nss_lock = PTHREAD_RWLOCK_INITIALIZER; |
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| 112 | |
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| 113 | /* |
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| 114 | * Runtime determination of whether we are dynamically linked or not. |
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| 115 | */ |
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| 116 | extern int _DYNAMIC __attribute__ ((weak)); |
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| 117 | #define is_dynamic() (&_DYNAMIC != NULL) |
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| 118 | |
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| 119 | /* |
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| 120 | * default sourcelist: `files' |
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| 121 | */ |
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| 122 | const ns_src __nsdefaultsrc[] = { |
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| 123 | { NSSRC_FILES, NS_SUCCESS }, |
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| 124 | { 0 }, |
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| 125 | }; |
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| 126 | |
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| 127 | /* Database, source mappings. */ |
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| 128 | static unsigned int _nsmapsize; |
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| 129 | static ns_dbt *_nsmap = NULL; |
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| 130 | |
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| 131 | /* NSS modules. */ |
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| 132 | static unsigned int _nsmodsize; |
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| 133 | static ns_mod *_nsmod; |
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| 134 | |
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| 135 | /* Placeholder for builtin modules' dlopen `handle'. */ |
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| 136 | static int __nss_builtin_handle; |
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| 137 | static void *nss_builtin_handle = &__nss_builtin_handle; |
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| 138 | |
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| 139 | #ifdef NS_CACHING |
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| 140 | /* |
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| 141 | * Cache lookup cycle prevention function - if !NULL then no cache lookups |
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| 142 | * will be made |
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| 143 | */ |
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| 144 | static void *nss_cache_cycle_prevention_func = NULL; |
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| 145 | #endif |
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| 146 | |
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| 147 | /* |
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| 148 | * When this is set to 1, nsdispatch won't use nsswitch.conf |
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| 149 | * but will consult the 'defaults' source list only. |
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| 150 | * NOTE: nested fallbacks (when nsdispatch calls fallback functions, |
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| 151 | * which in turn calls nsdispatch, which should call fallback |
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| 152 | * function) are not supported |
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| 153 | */ |
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| 154 | struct fb_state { |
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| 155 | int fb_dispatch; |
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| 156 | }; |
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| 157 | static void fb_endstate(void *); |
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| 158 | NSS_TLS_HANDLING(fb); |
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| 159 | |
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| 160 | /* |
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| 161 | * Attempt to spew relatively uniform messages to syslog. |
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| 162 | */ |
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| 163 | #define nss_log(level, fmt, ...) \ |
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| 164 | syslog((level), "NSSWITCH(%s): " fmt, __func__, __VA_ARGS__) |
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| 165 | #define nss_log_simple(level, s) \ |
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| 166 | syslog((level), "NSSWITCH(%s): " s, __func__) |
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| 167 | |
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| 168 | /* |
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| 169 | * Dynamically growable arrays are used for lists of databases, sources, |
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| 170 | * and modules. The following `vector' interface is used to isolate the |
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| 171 | * common operations. |
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| 172 | */ |
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| 173 | typedef int (*vector_comparison)(const void *, const void *); |
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| 174 | typedef void (*vector_free_elem)(void *); |
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| 175 | static void vector_sort(void *, unsigned int, size_t, |
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| 176 | vector_comparison); |
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| 177 | static void vector_free(void *, unsigned int *, size_t, |
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| 178 | vector_free_elem); |
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| 179 | static void *vector_ref(unsigned int, void *, unsigned int, size_t); |
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| 180 | static void *vector_search(const void *, void *, unsigned int, size_t, |
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| 181 | vector_comparison); |
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| 182 | static void *vector_append(const void *, void *, unsigned int *, size_t); |
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| 183 | |
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| 184 | |
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| 185 | /* |
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| 186 | * Internal interfaces. |
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| 187 | */ |
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| 188 | static int string_compare(const void *, const void *); |
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| 189 | static int mtab_compare(const void *, const void *); |
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| 190 | static int nss_configure(void); |
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| 191 | static void ns_dbt_free(ns_dbt *); |
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| 192 | static void ns_mod_free(ns_mod *); |
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| 193 | static void ns_src_free(ns_src **, int); |
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| 194 | static void nss_load_builtin_modules(void); |
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| 195 | static void nss_load_module(const char *, nss_module_register_fn); |
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| 196 | static void nss_atexit(void); |
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| 197 | /* nsparser */ |
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| 198 | extern FILE *_nsyyin; |
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| 199 | |
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| 200 | |
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| 201 | /* |
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| 202 | * The vector operations |
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| 203 | */ |
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| 204 | static void |
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| 205 | vector_sort(void *vec, unsigned int count, size_t esize, |
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| 206 | vector_comparison comparison) |
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| 207 | { |
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| 208 | qsort(vec, count, esize, comparison); |
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| 209 | } |
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| 210 | |
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| 211 | |
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| 212 | static void * |
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| 213 | vector_search(const void *key, void *vec, unsigned int count, size_t esize, |
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| 214 | vector_comparison comparison) |
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| 215 | { |
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| 216 | return (bsearch(key, vec, count, esize, comparison)); |
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| 217 | } |
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| 218 | |
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| 219 | |
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| 220 | static void * |
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| 221 | vector_append(const void *elem, void *vec, unsigned int *count, size_t esize) |
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| 222 | { |
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| 223 | void *p; |
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| 224 | |
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| 225 | if ((*count % ELEMSPERCHUNK) == 0) { |
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| 226 | p = realloc(vec, (*count + ELEMSPERCHUNK) * esize); |
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| 227 | if (p == NULL) { |
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| 228 | nss_log_simple(LOG_ERR, "memory allocation failure"); |
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| 229 | return (vec); |
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| 230 | } |
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| 231 | vec = p; |
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| 232 | } |
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| 233 | memmove((void *)(((uintptr_t)vec) + (*count * esize)), elem, esize); |
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| 234 | (*count)++; |
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| 235 | return (vec); |
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| 236 | } |
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| 237 | |
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| 238 | |
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| 239 | static void * |
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| 240 | vector_ref(unsigned int i, void *vec, unsigned int count, size_t esize) |
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| 241 | { |
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| 242 | if (i < count) |
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| 243 | return (void *)((uintptr_t)vec + (i * esize)); |
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| 244 | else |
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| 245 | return (NULL); |
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| 246 | } |
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| 247 | |
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| 248 | |
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| 249 | #define VECTOR_FREE(v, c, s, f) \ |
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| 250 | do { vector_free(v, c, s, f); v = NULL; } while (0) |
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| 251 | static void |
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| 252 | vector_free(void *vec, unsigned int *count, size_t esize, |
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| 253 | vector_free_elem free_elem) |
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| 254 | { |
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| 255 | unsigned int i; |
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| 256 | void *elem; |
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| 257 | |
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| 258 | for (i = 0; i < *count; i++) { |
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| 259 | elem = vector_ref(i, vec, *count, esize); |
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| 260 | if (elem != NULL) |
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| 261 | free_elem(elem); |
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| 262 | } |
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| 263 | free(vec); |
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| 264 | *count = 0; |
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| 265 | } |
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| 266 | |
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| 267 | /* |
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| 268 | * Comparison functions for vector_search. |
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| 269 | */ |
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| 270 | static int |
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| 271 | string_compare(const void *a, const void *b) |
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| 272 | { |
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| 273 | return (strcasecmp(*(const char * const *)a, *(const char * const *)b)); |
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| 274 | } |
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| 275 | |
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| 276 | |
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| 277 | static int |
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| 278 | mtab_compare(const void *a, const void *b) |
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| 279 | { |
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| 280 | int cmp; |
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| 281 | |
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| 282 | cmp = strcmp(((const ns_mtab *)a)->name, ((const ns_mtab *)b)->name); |
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| 283 | if (cmp != 0) |
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| 284 | return (cmp); |
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| 285 | else |
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| 286 | return (strcmp(((const ns_mtab *)a)->database, |
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| 287 | ((const ns_mtab *)b)->database)); |
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| 288 | } |
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| 289 | |
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| 290 | /* |
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| 291 | * NSS nsmap management. |
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| 292 | */ |
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| 293 | void |
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| 294 | _nsdbtaddsrc(ns_dbt *dbt, const ns_src *src) |
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| 295 | { |
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| 296 | const ns_mod *modp; |
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| 297 | |
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| 298 | dbt->srclist = vector_append(src, dbt->srclist, &dbt->srclistsize, |
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| 299 | sizeof(*src)); |
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| 300 | modp = vector_search(&src->name, _nsmod, _nsmodsize, sizeof(*_nsmod), |
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| 301 | string_compare); |
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| 302 | if (modp == NULL) |
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| 303 | nss_load_module(src->name, NULL); |
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| 304 | } |
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| 305 | |
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| 306 | |
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| 307 | #ifdef _NSS_DEBUG |
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| 308 | void |
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| 309 | _nsdbtdump(const ns_dbt *dbt) |
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| 310 | { |
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| 311 | int i; |
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| 312 | |
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| 313 | printf("%s (%d source%s):", dbt->name, dbt->srclistsize, |
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| 314 | dbt->srclistsize == 1 ? "" : "s"); |
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| 315 | for (i = 0; i < (int)dbt->srclistsize; i++) { |
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| 316 | printf(" %s", dbt->srclist[i].name); |
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| 317 | if (!(dbt->srclist[i].flags & |
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| 318 | (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) && |
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| 319 | (dbt->srclist[i].flags & NS_SUCCESS)) |
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| 320 | continue; |
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| 321 | printf(" ["); |
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| 322 | if (!(dbt->srclist[i].flags & NS_SUCCESS)) |
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| 323 | printf(" SUCCESS=continue"); |
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| 324 | if (dbt->srclist[i].flags & NS_UNAVAIL) |
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| 325 | printf(" UNAVAIL=return"); |
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| 326 | if (dbt->srclist[i].flags & NS_NOTFOUND) |
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| 327 | printf(" NOTFOUND=return"); |
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| 328 | if (dbt->srclist[i].flags & NS_TRYAGAIN) |
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| 329 | printf(" TRYAGAIN=return"); |
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| 330 | printf(" ]"); |
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| 331 | } |
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| 332 | printf("\n"); |
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| 333 | } |
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| 334 | #endif |
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| 335 | |
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| 336 | |
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| 337 | /* |
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| 338 | * The first time nsdispatch is called (during a process's lifetime, |
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| 339 | * or after nsswitch.conf has been updated), nss_configure will |
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| 340 | * prepare global data needed by NSS. |
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| 341 | */ |
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| 342 | static int |
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| 343 | nss_configure(void) |
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| 344 | { |
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| 345 | static pthread_mutex_t conf_lock = PTHREAD_MUTEX_INITIALIZER; |
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| 346 | static time_t confmod; |
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| 347 | struct stat statbuf; |
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| 348 | int result, isthreaded; |
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| 349 | const char *path; |
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| 350 | #ifdef NS_CACHING |
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| 351 | void *handle; |
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| 352 | #endif |
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| 353 | |
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| 354 | result = 0; |
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| 355 | isthreaded = __isthreaded; |
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| 356 | #if defined(_NSS_DEBUG) && defined(_NSS_SHOOT_FOOT) |
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| 357 | /* NOTE WELL: THIS IS A SECURITY HOLE. This must only be built |
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| 358 | * for debugging purposes and MUST NEVER be used in production. |
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| 359 | */ |
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| 360 | path = getenv("NSSWITCH_CONF"); |
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| 361 | if (path == NULL) |
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| 362 | #endif |
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| 363 | path = _PATH_NS_CONF; |
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| 364 | if (stat(path, &statbuf) != 0) |
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| 365 | return (0); |
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| 366 | if (statbuf.st_mtime <= confmod) |
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| 367 | return (0); |
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| 368 | if (isthreaded) { |
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| 369 | result = _pthread_mutex_trylock(&conf_lock); |
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| 370 | if (result != 0) |
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| 371 | return (0); |
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| 372 | (void)_pthread_rwlock_unlock(&nss_lock); |
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| 373 | result = _pthread_rwlock_wrlock(&nss_lock); |
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| 374 | if (result != 0) |
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| 375 | goto fin2; |
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| 376 | } |
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| 377 | _nsyyin = fopen(path, "r"); |
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| 378 | if (_nsyyin == NULL) |
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| 379 | goto fin; |
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| 380 | VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap), |
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| 381 | (vector_free_elem)ns_dbt_free); |
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| 382 | VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod), |
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| 383 | (vector_free_elem)ns_mod_free); |
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| 384 | nss_load_builtin_modules(); |
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| 385 | _nsyyparse(); |
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| 386 | (void)fclose(_nsyyin); |
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| 387 | vector_sort(_nsmap, _nsmapsize, sizeof(*_nsmap), string_compare); |
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| 388 | if (confmod == 0) |
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| 389 | (void)atexit(nss_atexit); |
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| 390 | confmod = statbuf.st_mtime; |
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| 391 | |
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| 392 | #ifdef NS_CACHING |
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| 393 | handle = libc_dlopen(NULL, RTLD_LAZY | RTLD_GLOBAL); |
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| 394 | if (handle != NULL) { |
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| 395 | nss_cache_cycle_prevention_func = dlsym(handle, |
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| 396 | "_nss_cache_cycle_prevention_function"); |
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| 397 | dlclose(handle); |
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| 398 | } |
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| 399 | #endif |
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| 400 | fin: |
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| 401 | if (isthreaded) { |
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| 402 | (void)_pthread_rwlock_unlock(&nss_lock); |
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| 403 | if (result == 0) |
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| 404 | result = _pthread_rwlock_rdlock(&nss_lock); |
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| 405 | } |
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| 406 | fin2: |
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| 407 | if (isthreaded) |
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| 408 | (void)_pthread_mutex_unlock(&conf_lock); |
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| 409 | return (result); |
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| 410 | } |
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| 411 | |
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| 412 | |
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| 413 | void |
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| 414 | _nsdbtput(const ns_dbt *dbt) |
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| 415 | { |
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| 416 | unsigned int i; |
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| 417 | ns_dbt *p; |
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| 418 | |
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| 419 | for (i = 0; i < _nsmapsize; i++) { |
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| 420 | p = vector_ref(i, _nsmap, _nsmapsize, sizeof(*_nsmap)); |
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| 421 | if (string_compare(&dbt->name, &p->name) == 0) { |
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| 422 | /* overwrite existing entry */ |
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| 423 | if (p->srclist != NULL) |
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| 424 | ns_src_free(&p->srclist, p->srclistsize); |
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| 425 | memmove(p, dbt, sizeof(*dbt)); |
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| 426 | return; |
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| 427 | } |
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| 428 | } |
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| 429 | _nsmap = vector_append(dbt, _nsmap, &_nsmapsize, sizeof(*_nsmap)); |
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| 430 | } |
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| 431 | |
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| 432 | |
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| 433 | static void |
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| 434 | ns_dbt_free(ns_dbt *dbt) |
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| 435 | { |
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| 436 | ns_src_free(&dbt->srclist, dbt->srclistsize); |
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| 437 | if (dbt->name) |
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| 438 | free((void *)dbt->name); |
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| 439 | } |
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| 440 | |
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| 441 | |
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| 442 | static void |
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| 443 | ns_src_free(ns_src **src, int srclistsize) |
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| 444 | { |
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| 445 | int i; |
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| 446 | |
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| 447 | for (i = 0; i < srclistsize; i++) |
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| 448 | if ((*src)[i].name != NULL) |
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| 449 | /* This one was allocated by nslexer. You'll just |
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| 450 | * have to trust me. |
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| 451 | */ |
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| 452 | free((void *)((*src)[i].name)); |
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| 453 | free(*src); |
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| 454 | *src = NULL; |
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| 455 | } |
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| 456 | |
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| 457 | |
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| 458 | |
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| 459 | /* |
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| 460 | * NSS module management. |
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| 461 | */ |
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| 462 | /* The built-in NSS modules are all loaded at once. */ |
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| 463 | #define NSS_BACKEND(name, reg) \ |
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| 464 | ns_mtab *reg(unsigned int *, nss_module_unregister_fn *); |
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| 465 | #include "nss_backends.h" |
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| 466 | #undef NSS_BACKEND |
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| 467 | |
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| 468 | static void |
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| 469 | nss_load_builtin_modules(void) |
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| 470 | { |
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| 471 | #define NSS_BACKEND(name, reg) nss_load_module(#name, reg); |
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| 472 | #include "nss_backends.h" |
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| 473 | #undef NSS_BACKEND |
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| 474 | } |
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| 475 | |
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| 476 | |
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| 477 | /* Load a built-in or dynamically linked module. If the `reg_fn' |
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| 478 | * argument is non-NULL, assume a built-in module and use reg_fn to |
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| 479 | * register it. Otherwise, search for a dynamic NSS module. |
---|
| 480 | */ |
---|
| 481 | static void |
---|
| 482 | nss_load_module(const char *source, nss_module_register_fn reg_fn) |
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| 483 | { |
---|
| 484 | char buf[PATH_MAX]; |
---|
| 485 | ns_mod mod; |
---|
| 486 | nss_module_register_fn fn; |
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| 487 | |
---|
| 488 | memset(&mod, 0, sizeof(mod)); |
---|
| 489 | mod.name = strdup(source); |
---|
| 490 | if (mod.name == NULL) { |
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| 491 | nss_log_simple(LOG_ERR, "memory allocation failure"); |
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| 492 | return; |
---|
| 493 | } |
---|
| 494 | if (reg_fn != NULL) { |
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| 495 | /* The placeholder is required, as a NULL handle |
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| 496 | * represents an invalid module. |
---|
| 497 | */ |
---|
| 498 | mod.handle = nss_builtin_handle; |
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| 499 | fn = reg_fn; |
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| 500 | } else if (!is_dynamic()) |
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| 501 | goto fin; |
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| 502 | #ifndef __rtems__ |
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| 503 | else { |
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| 504 | if (snprintf(buf, sizeof(buf), "nss_%s.so.%d", mod.name, |
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| 505 | NSS_MODULE_INTERFACE_VERSION) >= (int)sizeof(buf)) |
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| 506 | goto fin; |
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| 507 | mod.handle = libc_dlopen(buf, RTLD_LOCAL|RTLD_LAZY); |
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| 508 | if (mod.handle == NULL) { |
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| 509 | #ifdef _NSS_DEBUG |
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| 510 | /* This gets pretty annoying since the built-in |
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| 511 | * sources aren't modules yet. |
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| 512 | */ |
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| 513 | nss_log(LOG_DEBUG, "%s, %s", mod.name, dlerror()); |
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| 514 | #endif |
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| 515 | goto fin; |
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| 516 | } |
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| 517 | fn = (nss_module_register_fn)dlfunc(mod.handle, |
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| 518 | "nss_module_register"); |
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| 519 | if (fn == NULL) { |
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| 520 | (void)dlclose(mod.handle); |
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| 521 | mod.handle = NULL; |
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| 522 | nss_log(LOG_ERR, "%s, %s", mod.name, dlerror()); |
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| 523 | goto fin; |
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| 524 | } |
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| 525 | } |
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| 526 | #endif |
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| 527 | mod.mtab = fn(mod.name, &mod.mtabsize, &mod.unregister); |
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| 528 | if (mod.mtab == NULL || mod.mtabsize == 0) { |
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| 529 | #ifndef __rtems__ |
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| 530 | if (mod.handle != nss_builtin_handle) |
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| 531 | (void)dlclose(mod.handle); |
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| 532 | #endif |
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| 533 | mod.handle = NULL; |
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| 534 | nss_log(LOG_ERR, "%s, registration failed", mod.name); |
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| 535 | goto fin; |
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| 536 | } |
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| 537 | if (mod.mtabsize > 1) |
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| 538 | qsort(mod.mtab, mod.mtabsize, sizeof(mod.mtab[0]), |
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| 539 | mtab_compare); |
---|
| 540 | fin: |
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| 541 | _nsmod = vector_append(&mod, _nsmod, &_nsmodsize, sizeof(*_nsmod)); |
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| 542 | vector_sort(_nsmod, _nsmodsize, sizeof(*_nsmod), string_compare); |
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| 543 | } |
---|
| 544 | |
---|
| 545 | |
---|
| 546 | |
---|
| 547 | static void |
---|
| 548 | ns_mod_free(ns_mod *mod) |
---|
| 549 | { |
---|
| 550 | |
---|
| 551 | free(mod->name); |
---|
| 552 | if (mod->handle == NULL) |
---|
| 553 | return; |
---|
| 554 | if (mod->unregister != NULL) |
---|
| 555 | mod->unregister(mod->mtab, mod->mtabsize); |
---|
| 556 | #ifndef __rtems__ |
---|
| 557 | if (mod->handle != nss_builtin_handle) |
---|
| 558 | (void)dlclose(mod->handle); |
---|
| 559 | #endif |
---|
| 560 | } |
---|
| 561 | |
---|
| 562 | |
---|
| 563 | |
---|
| 564 | /* |
---|
| 565 | * Cleanup |
---|
| 566 | */ |
---|
| 567 | static void |
---|
| 568 | nss_atexit(void) |
---|
| 569 | { |
---|
| 570 | int isthreaded; |
---|
| 571 | |
---|
| 572 | isthreaded = __isthreaded; |
---|
| 573 | if (isthreaded) |
---|
| 574 | (void)_pthread_rwlock_wrlock(&nss_lock); |
---|
| 575 | VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap), |
---|
| 576 | (vector_free_elem)ns_dbt_free); |
---|
| 577 | VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod), |
---|
| 578 | (vector_free_elem)ns_mod_free); |
---|
| 579 | if (isthreaded) |
---|
| 580 | (void)_pthread_rwlock_unlock(&nss_lock); |
---|
| 581 | } |
---|
| 582 | |
---|
| 583 | |
---|
| 584 | |
---|
| 585 | /* |
---|
| 586 | * Finally, the actual implementation. |
---|
| 587 | */ |
---|
| 588 | static nss_method |
---|
| 589 | nss_method_lookup(const char *source, const char *database, |
---|
| 590 | const char *method, const ns_dtab disp_tab[], void **mdata) |
---|
| 591 | { |
---|
| 592 | ns_mod *mod; |
---|
| 593 | ns_mtab *match, key; |
---|
| 594 | int i; |
---|
| 595 | |
---|
| 596 | if (disp_tab != NULL) |
---|
| 597 | for (i = 0; disp_tab[i].src != NULL; i++) |
---|
| 598 | if (strcasecmp(source, disp_tab[i].src) == 0) { |
---|
| 599 | *mdata = disp_tab[i].mdata; |
---|
| 600 | return (disp_tab[i].method); |
---|
| 601 | } |
---|
| 602 | mod = vector_search(&source, _nsmod, _nsmodsize, sizeof(*_nsmod), |
---|
| 603 | string_compare); |
---|
| 604 | if (mod != NULL && mod->handle != NULL) { |
---|
| 605 | key.database = database; |
---|
| 606 | key.name = method; |
---|
| 607 | match = bsearch(&key, mod->mtab, mod->mtabsize, |
---|
| 608 | sizeof(mod->mtab[0]), mtab_compare); |
---|
| 609 | if (match != NULL) { |
---|
| 610 | *mdata = match->mdata; |
---|
| 611 | return (match->method); |
---|
| 612 | } |
---|
| 613 | } |
---|
| 614 | |
---|
| 615 | *mdata = NULL; |
---|
| 616 | return (NULL); |
---|
| 617 | } |
---|
| 618 | |
---|
| 619 | static void |
---|
| 620 | fb_endstate(void *p) |
---|
| 621 | { |
---|
| 622 | free(p); |
---|
| 623 | } |
---|
| 624 | |
---|
| 625 | __weak_reference(_nsdispatch, nsdispatch); |
---|
| 626 | |
---|
| 627 | int |
---|
| 628 | _nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database, |
---|
| 629 | const char *method_name, const ns_src defaults[], ...) |
---|
| 630 | { |
---|
| 631 | va_list ap; |
---|
| 632 | const ns_dbt *dbt; |
---|
| 633 | const ns_src *srclist; |
---|
| 634 | nss_method method, fb_method; |
---|
| 635 | void *mdata; |
---|
| 636 | int isthreaded, serrno, i, result, srclistsize; |
---|
| 637 | struct fb_state *st; |
---|
| 638 | |
---|
| 639 | #ifdef NS_CACHING |
---|
| 640 | nss_cache_data cache_data; |
---|
| 641 | nss_cache_data *cache_data_p; |
---|
| 642 | int cache_flag; |
---|
| 643 | #endif |
---|
| 644 | |
---|
| 645 | dbt = NULL; |
---|
| 646 | fb_method = NULL; |
---|
| 647 | |
---|
| 648 | isthreaded = __isthreaded; |
---|
| 649 | serrno = errno; |
---|
| 650 | if (isthreaded) { |
---|
| 651 | result = _pthread_rwlock_rdlock(&nss_lock); |
---|
| 652 | if (result != 0) { |
---|
| 653 | result = NS_UNAVAIL; |
---|
| 654 | goto fin; |
---|
| 655 | } |
---|
| 656 | } |
---|
| 657 | |
---|
| 658 | result = fb_getstate(&st); |
---|
| 659 | if (result != 0) { |
---|
| 660 | result = NS_UNAVAIL; |
---|
| 661 | goto fin; |
---|
| 662 | } |
---|
| 663 | |
---|
| 664 | result = nss_configure(); |
---|
| 665 | if (result != 0) { |
---|
| 666 | result = NS_UNAVAIL; |
---|
| 667 | goto fin; |
---|
| 668 | } |
---|
| 669 | if (st->fb_dispatch == 0) { |
---|
| 670 | dbt = vector_search(&database, _nsmap, _nsmapsize, sizeof(*_nsmap), |
---|
| 671 | string_compare); |
---|
| 672 | fb_method = nss_method_lookup(NSSRC_FALLBACK, database, |
---|
| 673 | method_name, disp_tab, &mdata); |
---|
| 674 | } |
---|
| 675 | |
---|
| 676 | if (dbt != NULL) { |
---|
| 677 | srclist = dbt->srclist; |
---|
| 678 | srclistsize = dbt->srclistsize; |
---|
| 679 | } else { |
---|
| 680 | srclist = defaults; |
---|
| 681 | srclistsize = 0; |
---|
| 682 | while (srclist[srclistsize].name != NULL) |
---|
| 683 | srclistsize++; |
---|
| 684 | } |
---|
| 685 | |
---|
| 686 | #ifdef NS_CACHING |
---|
| 687 | cache_data_p = NULL; |
---|
| 688 | cache_flag = 0; |
---|
| 689 | #endif |
---|
| 690 | for (i = 0; i < srclistsize; i++) { |
---|
| 691 | result = NS_NOTFOUND; |
---|
| 692 | method = nss_method_lookup(srclist[i].name, database, |
---|
| 693 | method_name, disp_tab, &mdata); |
---|
| 694 | |
---|
| 695 | if (method != NULL) { |
---|
| 696 | #ifdef NS_CACHING |
---|
| 697 | if (strcmp(srclist[i].name, NSSRC_CACHE) == 0 && |
---|
| 698 | nss_cache_cycle_prevention_func == NULL) { |
---|
| 699 | #ifdef NS_STRICT_LIBC_EID_CHECKING |
---|
| 700 | if (issetugid() != 0) |
---|
| 701 | continue; |
---|
| 702 | #endif |
---|
| 703 | cache_flag = 1; |
---|
| 704 | |
---|
| 705 | memset(&cache_data, 0, sizeof(nss_cache_data)); |
---|
| 706 | cache_data.info = (nss_cache_info const *)mdata; |
---|
| 707 | cache_data_p = &cache_data; |
---|
| 708 | |
---|
| 709 | va_start(ap, defaults); |
---|
| 710 | if (cache_data.info->id_func != NULL) |
---|
| 711 | result = __nss_common_cache_read(retval, |
---|
| 712 | cache_data_p, ap); |
---|
| 713 | else if (cache_data.info->marshal_func != NULL) |
---|
| 714 | result = __nss_mp_cache_read(retval, |
---|
| 715 | cache_data_p, ap); |
---|
| 716 | else |
---|
| 717 | result = __nss_mp_cache_end(retval, |
---|
| 718 | cache_data_p, ap); |
---|
| 719 | va_end(ap); |
---|
| 720 | } else { |
---|
| 721 | cache_flag = 0; |
---|
| 722 | errno = 0; |
---|
| 723 | va_start(ap, defaults); |
---|
| 724 | result = method(retval, mdata, ap); |
---|
| 725 | va_end(ap); |
---|
| 726 | } |
---|
| 727 | #else /* NS_CACHING */ |
---|
| 728 | errno = 0; |
---|
| 729 | va_start(ap, defaults); |
---|
| 730 | result = method(retval, mdata, ap); |
---|
| 731 | va_end(ap); |
---|
| 732 | #endif /* NS_CACHING */ |
---|
| 733 | |
---|
| 734 | if (result & (srclist[i].flags)) |
---|
| 735 | break; |
---|
| 736 | } else { |
---|
| 737 | if (fb_method != NULL) { |
---|
| 738 | st->fb_dispatch = 1; |
---|
| 739 | va_start(ap, defaults); |
---|
| 740 | result = fb_method(retval, |
---|
| 741 | (void *)srclist[i].name, ap); |
---|
| 742 | va_end(ap); |
---|
| 743 | st->fb_dispatch = 0; |
---|
| 744 | } else |
---|
| 745 | nss_log(LOG_DEBUG, "%s, %s, %s, not found, " |
---|
| 746 | "and no fallback provided", |
---|
| 747 | srclist[i].name, database, method_name); |
---|
| 748 | } |
---|
| 749 | } |
---|
| 750 | |
---|
| 751 | #ifdef NS_CACHING |
---|
| 752 | if (cache_data_p != NULL && |
---|
| 753 | (result & (NS_NOTFOUND | NS_SUCCESS)) && cache_flag == 0) { |
---|
| 754 | va_start(ap, defaults); |
---|
| 755 | if (result == NS_SUCCESS) { |
---|
| 756 | if (cache_data.info->id_func != NULL) |
---|
| 757 | __nss_common_cache_write(retval, cache_data_p, |
---|
| 758 | ap); |
---|
| 759 | else if (cache_data.info->marshal_func != NULL) |
---|
| 760 | __nss_mp_cache_write(retval, cache_data_p, ap); |
---|
| 761 | } else if (result == NS_NOTFOUND) { |
---|
| 762 | if (cache_data.info->id_func == NULL) { |
---|
| 763 | if (cache_data.info->marshal_func != NULL) |
---|
| 764 | __nss_mp_cache_write_submit(retval, |
---|
| 765 | cache_data_p, ap); |
---|
| 766 | } else |
---|
| 767 | __nss_common_cache_write_negative(cache_data_p); |
---|
| 768 | } |
---|
| 769 | va_end(ap); |
---|
| 770 | } |
---|
| 771 | #endif /* NS_CACHING */ |
---|
| 772 | |
---|
| 773 | if (isthreaded) |
---|
| 774 | (void)_pthread_rwlock_unlock(&nss_lock); |
---|
| 775 | fin: |
---|
| 776 | errno = serrno; |
---|
| 777 | return (result); |
---|
| 778 | } |
---|