xref: /netbsd-src/sys/miscfs/umapfs/umap_subr.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: umap_subr.c,v 1.25 2007/06/30 15:27:03 dsl Exp $	*/
2 
3 /*
4  * Copyright (c) 1999 National Aeronautics & Space Administration
5  * All rights reserved.
6  *
7  * This software was written by William Studenmund of the
8  * Numerical Aerospace Simulation Facility, NASA Ames Research Center.
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  * 3. Neither the name of the National Aeronautics & Space Administration
19  *    nor the names of its contributors may be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB-
27  * UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
28  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 /*
36  * Copyright (c) 1992, 1993, 1995
37  *	The Regents of the University of California.  All rights reserved.
38  *
39  * This code is derived from software donated to Berkeley by
40  * Jan-Simon Pendry.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  *	from: Id: lofs_subr.c, v 1.11 1992/05/30 10:05:43 jsp Exp
67  *	@(#)umap_subr.c	8.9 (Berkeley) 5/14/95
68  */
69 
70 #include <sys/cdefs.h>
71 __KERNEL_RCSID(0, "$NetBSD: umap_subr.c,v 1.25 2007/06/30 15:27:03 dsl Exp $");
72 
73 #include <sys/param.h>
74 #include <sys/systm.h>
75 #include <sys/proc.h>
76 #include <sys/time.h>
77 #include <sys/vnode.h>
78 #include <sys/mount.h>
79 #include <sys/namei.h>
80 #include <sys/malloc.h>
81 #include <sys/kauth.h>
82 
83 #include <miscfs/specfs/specdev.h>
84 #include <miscfs/umapfs/umap.h>
85 
86 u_long umap_findid(u_long, u_long [][2], int);
87 int umap_node_alloc(struct mount *, struct vnode *,
88 				struct vnode **);
89 
90 /*
91  * umap_findid is called by various routines in umap_vnodeops.c to
92  * find a user or group id in a map.
93  */
94 u_long
95 umap_findid(id, map, nentries)
96 	u_long id;
97 	u_long map[][2];
98 	int nentries;
99 {
100 	int i;
101 
102 	/* Find uid entry in map */
103 	i = 0;
104 	while ((i<nentries) && ((map[i][0]) != id))
105 		i++;
106 
107 	if (i < nentries)
108 		return (map[i][1]);
109 	else
110 		return (-1);
111 
112 }
113 
114 /*
115  * umap_reverse_findid is called by umap_getattr() in umap_vnodeops.c to
116  * find a user or group id in a map, in reverse.
117  */
118 u_long
119 umap_reverse_findid(id, map, nentries)
120 	u_long id;
121 	u_long map[][2];
122 	int nentries;
123 {
124 	int i;
125 
126 	/* Find uid entry in map */
127 	i = 0;
128 	while ((i<nentries) && ((map[i][1]) != id))
129 		i++;
130 
131 	if (i < nentries)
132 		return (map[i][0]);
133 	else
134 		return (-1);
135 
136 }
137 
138 /* umap_mapids maps all of the ids in a credential, both user and group. */
139 
140 void
141 umap_mapids(v_mount, credp)
142 	struct mount *v_mount;
143 	kauth_cred_t credp;
144 {
145 	int i, unentries, gnentries;
146 	uid_t uid;
147 	gid_t gid;
148 	u_long (*usermap)[2], (*groupmap)[2];
149 	gid_t groups[NGROUPS];
150 	uint16_t ngroups;
151 
152 	if (credp == NOCRED)
153 		return;
154 
155 	unentries =  MOUNTTOUMAPMOUNT(v_mount)->info_nentries;
156 	usermap =  MOUNTTOUMAPMOUNT(v_mount)->info_mapdata;
157 	gnentries =  MOUNTTOUMAPMOUNT(v_mount)->info_gnentries;
158 	groupmap =  MOUNTTOUMAPMOUNT(v_mount)->info_gmapdata;
159 
160 	/* Find uid entry in map */
161 
162 	uid = (uid_t) umap_findid(kauth_cred_geteuid(credp), usermap, unentries);
163 
164 	if (uid != -1)
165 		kauth_cred_seteuid(credp, uid);
166 	else
167 		kauth_cred_seteuid(credp, (uid_t)NOBODY);
168 
169 #if 1
170 	/* cr_gid is the same as cr_groups[0] in 4BSD, but not in NetBSD */
171 
172 	/* Find gid entry in map */
173 
174 	gid = (gid_t) umap_findid(kauth_cred_getegid(credp), groupmap, gnentries);
175 
176 	if (gid != -1)
177 		kauth_cred_setegid(credp, gid);
178 	else
179 		kauth_cred_setegid(credp, NULLGROUP);
180 #endif
181 
182 	/* Now we must map each of the set of groups in the cr_groups
183 		structure. */
184 
185 	ngroups = kauth_cred_ngroups(credp);
186 	for (i = 0; i < ngroups; i++) {
187 		/* XXX elad: can't we just skip cases where gid == -1? */
188 		groups[i] = kauth_cred_group(credp, i);
189 		gid = (gid_t) umap_findid(groups[i],
190 					  groupmap, gnentries);
191 		if (gid != -1)
192 			groups[i] = gid;
193 		else
194 			groups[i] = NULLGROUP;
195 	}
196 
197 	kauth_cred_setgroups(credp, groups, ngroups, -1, UIO_SYSSPACE);
198 }
199