1 /*	$NetBSD: nsswitch.h,v 1.21 2011/07/17 20:54:34 joerg Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997, 1998, 1999, 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _NSSWITCH_H
33 #define _NSSWITCH_H	1
34 
35 #include <sys/types.h>
36 #include <stdarg.h>
37 
38 #define	NSS_MODULE_INTERFACE_VERSION	0
39 
40 #ifndef _PATH_NS_CONF
41 #define _PATH_NS_CONF	"/etc/nsswitch.conf"
42 #endif
43 
44 #define	NS_CONTINUE	0
45 #define	NS_RETURN	1
46 
47 /*
48  * Layout of:
49  *	uint32_t ns_src.flags
50  */
51 	/* nsswitch.conf status codes and nsdispatch(3) return values */
52 #define	NS_SUCCESS	(1<<0)		/* entry was found */
53 #define	NS_UNAVAIL	(1<<1)		/* source not responding, or corrupt */
54 #define	NS_NOTFOUND	(1<<2)		/* source responded 'no such entry' */
55 #define	NS_TRYAGAIN	(1<<3)		/* source busy, may respond to retrys */
56 #define	NS_STATUSMASK	0x000000ff	/* bitmask to get the status flags */
57 
58 	/* internal nsdispatch(3) flags; not settable in nsswitch.conf(5)  */
59 #define	NS_FORCEALL	(1<<8)		/* force all methods to be invoked; */
60 
61 /*
62  * Currently implemented sources.
63  */
64 #define NSSRC_FILES	"files"		/* local files */
65 #define	NSSRC_DNS	"dns"		/* DNS; IN for hosts, HS for others */
66 #define	NSSRC_NIS	"nis"		/* YP/NIS */
67 #define	NSSRC_COMPAT	"compat"	/* passwd,group in YP compat mode */
68 
69 /*
70  * Currently implemented databases.
71  */
72 #define NSDB_HOSTS		"hosts"
73 #define NSDB_GROUP		"group"
74 #define NSDB_GROUP_COMPAT	"group_compat"
75 #define NSDB_NETGROUP		"netgroup"
76 #define NSDB_NETWORKS		"networks"
77 #define NSDB_PASSWD		"passwd"
78 #define NSDB_PASSWD_COMPAT	"passwd_compat"
79 #define NSDB_SHELLS		"shells"
80 
81 /*
82  * Suggested databases to implement.
83  */
84 #define NSDB_ALIASES		"aliases"
85 #define NSDB_AUTH		"auth"
86 #define NSDB_AUTOMOUNT		"automount"
87 #define NSDB_BOOTPARAMS		"bootparams"
88 #define NSDB_ETHERS		"ethers"
89 #define NSDB_EXPORTS		"exports"
90 #define NSDB_NETMASKS		"netmasks"
91 #define NSDB_PHONES		"phones"
92 #define NSDB_PRINTCAP		"printcap"
93 #define NSDB_PROTOCOLS		"protocols"
94 #define NSDB_REMOTE		"remote"
95 #define NSDB_RPC		"rpc"
96 #define NSDB_SENDMAILVARS	"sendmailvars"
97 #define NSDB_SERVICES		"services"
98 #define NSDB_TERMCAP		"termcap"
99 #define NSDB_TTYS		"ttys"
100 
101 /*
102  * ns_dtab `callback' function signature.
103  */
104 typedef	int (*nss_method)(void *, void *, va_list);
105 
106 /*
107  * ns_dtab - `nsswitch dispatch table'
108  * Contains an entry for each source and the appropriate function to call.
109  */
110 typedef struct {
111 	const char	 *src;
112 	nss_method	 callback;
113 	void		 *cb_data;
114 } ns_dtab;
115 
116 /*
117  * Macros to help build an ns_dtab[]
118  */
119 #define NS_FILES_CB(F,C)	{ NSSRC_FILES,	F,	__UNCONST(C) },
120 #define NS_COMPAT_CB(F,C)	{ NSSRC_COMPAT,	F,	__UNCONST(C) },
121 
122 #ifdef HESIOD
123 #   define NS_DNS_CB(F,C)	{ NSSRC_DNS,	F,	__UNCONST(C) },
124 #else
125 #   define NS_DNS_CB(F,C)
126 #endif
127 
128 #ifdef YP
129 #   define NS_NIS_CB(F,C)	{ NSSRC_NIS,	F,	__UNCONST(C) },
130 #else
131 #   define NS_NIS_CB(F,C)
132 #endif
133 #define	NS_NULL_CB		{ .src = NULL },
134 
135 /*
136  * ns_src - `nsswitch source'
137  * Used by the nsparser routines to store a mapping between a source
138  * and its dispatch control flags for a given database.
139  */
140 typedef struct {
141 	const char	*name;
142 	uint32_t	 flags;
143 } ns_src;
144 
145 
146 /*
147  * Default sourcelists (if nsswitch.conf is missing, corrupt,
148  * or the requested database doesn't have an entry)
149  */
150 extern const ns_src __nsdefaultsrc[];
151 extern const ns_src __nsdefaultcompat[];
152 extern const ns_src __nsdefaultcompat_forceall[];
153 extern const ns_src __nsdefaultfiles[];
154 extern const ns_src __nsdefaultfiles_forceall[];
155 extern const ns_src __nsdefaultnis[];
156 extern const ns_src __nsdefaultnis_forceall[];
157 
158 
159 /*
160  * ns_mtab - `nsswitch method table'
161  * An nsswitch module provides a mapping from (database name, method name)
162  * tuples to the nss_method and associated callback data.  Effectively,
163  * ns_dtab, but used for dynamically loaded modules.
164  */
165 typedef struct {
166 	const char	*database;
167 	const char	*name;
168 	nss_method	 method;
169 	void		*mdata;
170 } ns_mtab;
171 
172 /*
173  * nss_module_register_fn - module registration function
174  *	called at module load
175  * nss_module_unregister_fn - module un-registration function
176  *	called at module unload
177  */
178 typedef	void (*nss_module_unregister_fn)(ns_mtab *, u_int);
179 typedef	ns_mtab *(*nss_module_register_fn)(const char *, u_int *,
180 					   nss_module_unregister_fn *);
181 
182 #ifdef _NS_PRIVATE
183 
184 /*
185  * Private data structures for back-end nsswitch implementation.
186  */
187 
188 /*
189  * ns_dbt - `nsswitch database thang'
190  * For each database in /etc/nsswitch.conf there is a ns_dbt, with its
191  * name and a list of ns_src's containing the source information.
192  */
193 typedef struct {
194 	const char	*name;		/* name of database */
195 	ns_src		*srclist;	/* list of sources */
196 	u_int		 srclistsize;	/* size of srclist */
197 } ns_dbt;
198 
199 /*
200  * ns_mod - `nsswitch module'
201  */
202 typedef struct {
203 	const char	*name;		/* module name */
204 	void		*handle;	/* handle from dlopen() */
205 	ns_mtab		*mtab;		/* method table */
206 	u_int		 mtabsize;	/* size of mtab */
207 					/* called to unload module */
208 	nss_module_unregister_fn unregister;
209 } ns_mod;
210 
211 #endif /* _NS_PRIVATE */
212 
213 
214 #include <sys/cdefs.h>
215 
216 __BEGIN_DECLS
217 int	nsdispatch(void *, const ns_dtab [], const char *,
218 			const char *, const ns_src [], ...) __LIBC_ABI_PUBLIC__;
219 
220 #ifdef _NS_PRIVATE
221 int		 _nsdbtaddsrc(ns_dbt *, const ns_src *);
222 void		 _nsdbtdump(const ns_dbt *);
223 int		 _nsdbtput(const ns_dbt *);
224 void		 _nsyyerror(const char *);
225 int		 _nsyylex(void);
226 #endif /* _NS_PRIVATE */
227 
228 __END_DECLS
229 
230 #endif /* !_NSSWITCH_H */
231