1 /*	$NetBSD: nsswitch.h,v 1.20 2008/04/28 20:22:54 martin 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 /*
36  * Don't use va_list in prototypes.   va_list is typedef'd in two places
37  * (<machine/varargs.h> and <machine/stdarg.h>), so if we include one of
38  * them here we may collide with the utility's includes.  It's unreasonable
39  * for utilities to have to include one of them to include nsswitch.h, so
40  * we get _BSD_VA_LIST_ from <machine/ansi.h> and use it.
41  */
42 #include <machine/ansi.h>
43 #include <sys/types.h>
44 
45 #define	NSS_MODULE_INTERFACE_VERSION	0
46 
47 #ifndef _PATH_NS_CONF
48 #define _PATH_NS_CONF	"/etc/nsswitch.conf"
49 #endif
50 
51 #define	NS_CONTINUE	0
52 #define	NS_RETURN	1
53 
54 /*
55  * Layout of:
56  *	uint32_t ns_src.flags
57  */
58 	/* nsswitch.conf status codes and nsdispatch(3) return values */
59 #define	NS_SUCCESS	(1<<0)		/* entry was found */
60 #define	NS_UNAVAIL	(1<<1)		/* source not responding, or corrupt */
61 #define	NS_NOTFOUND	(1<<2)		/* source responded 'no such entry' */
62 #define	NS_TRYAGAIN	(1<<3)		/* source busy, may respond to retrys */
63 #define	NS_STATUSMASK	0x000000ff	/* bitmask to get the status flags */
64 
65 	/* internal nsdispatch(3) flags; not settable in nsswitch.conf(5)  */
66 #define	NS_FORCEALL	(1<<8)		/* force all methods to be invoked; */
67 
68 /*
69  * Currently implemented sources.
70  */
71 #define NSSRC_FILES	"files"		/* local files */
72 #define	NSSRC_DNS	"dns"		/* DNS; IN for hosts, HS for others */
73 #define	NSSRC_NIS	"nis"		/* YP/NIS */
74 #define	NSSRC_COMPAT	"compat"	/* passwd,group in YP compat mode */
75 
76 /*
77  * Currently implemented databases.
78  */
79 #define NSDB_HOSTS		"hosts"
80 #define NSDB_GROUP		"group"
81 #define NSDB_GROUP_COMPAT	"group_compat"
82 #define NSDB_NETGROUP		"netgroup"
83 #define NSDB_NETWORKS		"networks"
84 #define NSDB_PASSWD		"passwd"
85 #define NSDB_PASSWD_COMPAT	"passwd_compat"
86 #define NSDB_SHELLS		"shells"
87 
88 /*
89  * Suggested databases to implement.
90  */
91 #define NSDB_ALIASES		"aliases"
92 #define NSDB_AUTH		"auth"
93 #define NSDB_AUTOMOUNT		"automount"
94 #define NSDB_BOOTPARAMS		"bootparams"
95 #define NSDB_ETHERS		"ethers"
96 #define NSDB_EXPORTS		"exports"
97 #define NSDB_NETMASKS		"netmasks"
98 #define NSDB_PHONES		"phones"
99 #define NSDB_PRINTCAP		"printcap"
100 #define NSDB_PROTOCOLS		"protocols"
101 #define NSDB_REMOTE		"remote"
102 #define NSDB_RPC		"rpc"
103 #define NSDB_SENDMAILVARS	"sendmailvars"
104 #define NSDB_SERVICES		"services"
105 #define NSDB_TERMCAP		"termcap"
106 #define NSDB_TTYS		"ttys"
107 
108 /*
109  * ns_dtab `callback' function signature.
110  */
111 typedef	int (*nss_method)(void *, void *, _BSD_VA_LIST_);
112 
113 /*
114  * ns_dtab - `nsswitch dispatch table'
115  * Contains an entry for each source and the appropriate function to call.
116  */
117 typedef struct {
118 	const char	 *src;
119 	nss_method	 callback;
120 	void		 *cb_data;
121 } ns_dtab;
122 
123 /*
124  * Macros to help build an ns_dtab[]
125  */
126 #define NS_FILES_CB(F,C)	{ NSSRC_FILES,	F,	__UNCONST(C) },
127 #define NS_COMPAT_CB(F,C)	{ NSSRC_COMPAT,	F,	__UNCONST(C) },
128 
129 #ifdef HESIOD
130 #   define NS_DNS_CB(F,C)	{ NSSRC_DNS,	F,	__UNCONST(C) },
131 #else
132 #   define NS_DNS_CB(F,C)
133 #endif
134 
135 #ifdef YP
136 #   define NS_NIS_CB(F,C)	{ NSSRC_NIS,	F,	__UNCONST(C) },
137 #else
138 #   define NS_NIS_CB(F,C)
139 #endif
140 #define	NS_NULL_CB		{ NULL, NULL, NULL },
141 
142 /*
143  * ns_src - `nsswitch source'
144  * Used by the nsparser routines to store a mapping between a source
145  * and its dispatch control flags for a given database.
146  */
147 typedef struct {
148 	const char	*name;
149 	uint32_t	 flags;
150 } ns_src;
151 
152 
153 /*
154  * Default sourcelists (if nsswitch.conf is missing, corrupt,
155  * or the requested database doesn't have an entry)
156  */
157 extern const ns_src __nsdefaultsrc[];
158 extern const ns_src __nsdefaultcompat[];
159 extern const ns_src __nsdefaultcompat_forceall[];
160 extern const ns_src __nsdefaultfiles[];
161 extern const ns_src __nsdefaultfiles_forceall[];
162 extern const ns_src __nsdefaultnis[];
163 extern const ns_src __nsdefaultnis_forceall[];
164 
165 
166 /*
167  * ns_mtab - `nsswitch method table'
168  * An nsswitch module provides a mapping from (database name, method name)
169  * tuples to the nss_method and associated callback data.  Effectively,
170  * ns_dtab, but used for dynamically loaded modules.
171  */
172 typedef struct {
173 	const char	*database;
174 	const char	*name;
175 	nss_method	 method;
176 	void		*mdata;
177 } ns_mtab;
178 
179 /*
180  * nss_module_register_fn - module registration function
181  *	called at module load
182  * nss_module_unregister_fn - module un-registration function
183  *	called at module unload
184  */
185 typedef	void (*nss_module_unregister_fn)(ns_mtab *, u_int);
186 typedef	ns_mtab *(*nss_module_register_fn)(const char *, u_int *,
187 					   nss_module_unregister_fn *);
188 
189 #ifdef _NS_PRIVATE
190 
191 /*
192  * Private data structures for back-end nsswitch implementation.
193  */
194 
195 /*
196  * ns_dbt - `nsswitch database thang'
197  * For each database in /etc/nsswitch.conf there is a ns_dbt, with its
198  * name and a list of ns_src's containing the source information.
199  */
200 typedef struct {
201 	const char	*name;		/* name of database */
202 	ns_src		*srclist;	/* list of sources */
203 	u_int		 srclistsize;	/* size of srclist */
204 } ns_dbt;
205 
206 /*
207  * ns_mod - `nsswitch module'
208  */
209 typedef struct {
210 	const char	*name;		/* module name */
211 	void		*handle;	/* handle from dlopen() */
212 	ns_mtab		*mtab;		/* method table */
213 	u_int		 mtabsize;	/* size of mtab */
214 					/* called to unload module */
215 	nss_module_unregister_fn unregister;
216 } ns_mod;
217 
218 #endif /* _NS_PRIVATE */
219 
220 
221 #include <sys/cdefs.h>
222 
223 __BEGIN_DECLS
224 int	nsdispatch(void *, const ns_dtab [], const char *,
225 			const char *, const ns_src [], ...);
226 
227 #ifdef _NS_PRIVATE
228 int		 _nsdbtaddsrc(ns_dbt *, const ns_src *);
229 void		 _nsdbtdump(const ns_dbt *);
230 int		 _nsdbtput(const ns_dbt *);
231 void		 _nsyyerror(const char *);
232 int		 _nsyylex(void);
233 #endif /* _NS_PRIVATE */
234 
235 __END_DECLS
236 
237 #endif /* !_NSSWITCH_H */
238