sys/miscfs/umapfs/umap_subr.c

   1 /*      $NetBSD: umap_subr.c,v 1.27 2009/03/14 15:36:23 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 1.27 2009/03/14 15:36:23 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(u_long id, u_long map[][2], int nentries)
  96 {
  97         int i;
  98
  99         /* Find uid entry in map */
 100         i = 0;
 101         while ((i<nentries) && ((map[i][0]) != id))
 102                 i++;
 103
 104         if (i < nentries)
 105                 return (map[i][1]);
 106         else
 107                 return (-1);
 108
 109 }
 110
 111 /*
 112  * umap_reverse_findid is called by umap_getattr() in umap_vnodeops.c to
 113  * find a user or group id in a map, in reverse.
 114  */
 115 u_long
 116 umap_reverse_findid(u_long id, u_long map[][2], int nentries)
 117 {
 118         int i;
 119
 120         /* Find uid entry in map */
 121         i = 0;
 122         while ((i<nentries) && ((map[i][1]) != id))
 123                 i++;
 124
 125         if (i < nentries)
 126                 return (map[i][0]);
 127         else
 128                 return (-1);
 129
 130 }
 131
 132 /* umap_mapids maps all of the ids in a credential, both user and group. */
 133
 134 void
 135 umap_mapids(struct mount *v_mount, kauth_cred_t credp)
 136 {
 137         int i, unentries, gnentries;
 138         uid_t uid;
 139         gid_t gid;
 140         u_long (*usermap)[2], (*groupmap)[2];
 141         gid_t groups[NGROUPS];
 142         uint16_t ngroups;
 143
 144         if (credp == NOCRED || credp == FSCRED)
 145                 return;
 146
 147         unentries =  MOUNTTOUMAPMOUNT(v_mount)->info_nentries;
 148         usermap =  MOUNTTOUMAPMOUNT(v_mount)->info_mapdata;
 149         gnentries =  MOUNTTOUMAPMOUNT(v_mount)->info_gnentries;
 150         groupmap =  MOUNTTOUMAPMOUNT(v_mount)->info_gmapdata;
 151
 152         /* Find uid entry in map */
 153
 154         uid = (uid_t) umap_findid(kauth_cred_geteuid(credp), usermap, unentries);
 155
 156         if (uid != -1)
 157                 kauth_cred_seteuid(credp, uid);
 158         else
 159                 kauth_cred_seteuid(credp, (uid_t)NOBODY);
 160
 161 #if 1
 162         /* cr_gid is the same as cr_groups[0] in 4BSD, but not in NetBSD */
 163
 164         /* Find gid entry in map */
 165
 166         gid = (gid_t) umap_findid(kauth_cred_getegid(credp), groupmap, gnentries);
 167
 168         if (gid != -1)
 169                 kauth_cred_setegid(credp, gid);
 170         else
 171                 kauth_cred_setegid(credp, NULLGROUP);
 172 #endif
 173
 174         /* Now we must map each of the set of groups in the cr_groups
 175                 structure. */
 176
 177         ngroups = kauth_cred_ngroups(credp);
 178         for (i = 0; i < ngroups; i++) {
 179                 /* XXX elad: can't we just skip cases where gid == -1? */
 180                 groups[i] = kauth_cred_group(credp, i);
 181                 gid = (gid_t) umap_findid(groups[i],
 182                                           groupmap, gnentries);
 183                 if (gid != -1)
 184                         groups[i] = gid;
 185                 else
 186                         groups[i] = NULLGROUP;
 187         }
 188
 189         kauth_cred_setgroups(credp, groups, ngroups, -1, UIO_SYSSPACE);
 190 }