crypto/external/bsd/heimdal/dist/kcm/acl.c

   1 /*      $NetBSD: acl.c,v 1.1.1.1 2011/04/13 18:14:35 elric Exp $        */
   2
   3 /*
   4  * Copyright (c) 2005, PADL Software Pty Ltd.
   5  * All rights reserved.
   6  *
   7  * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * 3. Neither the name of PADL Software nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #include "kcm_locl.h"
  38
  39 krb5_error_code
  40 kcm_access(krb5_context context,
  41            kcm_client *client,
  42            kcm_operation opcode,
  43            kcm_ccache ccache)
  44 {
  45     int read_p = 0;
  46     int write_p = 0;
  47     uint16_t mask;
  48     krb5_error_code ret;
  49
  50     KCM_ASSERT_VALID(ccache);
  51
  52     switch (opcode) {
  53     case KCM_OP_INITIALIZE:
  54     case KCM_OP_DESTROY:
  55     case KCM_OP_STORE:
  56     case KCM_OP_REMOVE_CRED:
  57     case KCM_OP_SET_FLAGS:
  58     case KCM_OP_CHOWN:
  59     case KCM_OP_CHMOD:
  60     case KCM_OP_GET_INITIAL_TICKET:
  61     case KCM_OP_GET_TICKET:
  62     case KCM_OP_MOVE_CACHE:
  63     case KCM_OP_SET_DEFAULT_CACHE:
  64     case KCM_OP_SET_KDC_OFFSET:
  65         write_p = 1;
  66         read_p = 0;
  67         break;
  68     case KCM_OP_NOOP:
  69     case KCM_OP_GET_NAME:
  70     case KCM_OP_RESOLVE:
  71     case KCM_OP_GEN_NEW:
  72     case KCM_OP_RETRIEVE:
  73     case KCM_OP_GET_PRINCIPAL:
  74     case KCM_OP_GET_CRED_UUID_LIST:
  75     case KCM_OP_GET_CRED_BY_UUID:
  76     case KCM_OP_GET_CACHE_UUID_LIST:
  77     case KCM_OP_GET_CACHE_BY_UUID:
  78     case KCM_OP_GET_DEFAULT_CACHE:
  79     case KCM_OP_GET_KDC_OFFSET:
  80         write_p = 0;
  81         read_p = 1;
  82         break;
  83     default:
  84         ret = KRB5_FCC_PERM;
  85         goto out;
  86     }
  87
  88     if (ccache->flags & KCM_FLAGS_OWNER_IS_SYSTEM) {
  89         /* System caches cannot be reinitialized or destroyed by users */
  90         if (opcode == KCM_OP_INITIALIZE ||
  91             opcode == KCM_OP_DESTROY ||
  92             opcode == KCM_OP_REMOVE_CRED ||
  93             opcode == KCM_OP_MOVE_CACHE) {
  94             ret = KRB5_FCC_PERM;
  95             goto out;
  96         }
  97
  98         /* Let root always read system caches */
  99         if (CLIENT_IS_ROOT(client)) {
 100             ret = 0;
 101             goto out;
 102         }
 103     }
 104
 105     /* start out with "other" mask */
 106     mask = S_IROTH|S_IWOTH;
 107
 108     /* root can do anything */
 109     if (CLIENT_IS_ROOT(client)) {
 110         if (read_p)
 111             mask |= S_IRUSR|S_IRGRP|S_IROTH;
 112         if (write_p)
 113             mask |= S_IWUSR|S_IWGRP|S_IWOTH;
 114     }
 115     /* same session same as owner */
 116     if (kcm_is_same_session(client, ccache->uid, ccache->session)) {
 117         if (read_p)
 118             mask |= S_IROTH;
 119         if (write_p)
 120             mask |= S_IWOTH;
 121     }
 122     /* owner */
 123     if (client->uid == ccache->uid) {
 124         if (read_p)
 125             mask |= S_IRUSR;
 126         if (write_p)
 127             mask |= S_IWUSR;
 128     }
 129     /* group */
 130     if (client->gid == ccache->gid) {
 131         if (read_p)
 132             mask |= S_IRGRP;
 133         if (write_p)
 134             mask |= S_IWGRP;
 135     }
 136
 137     ret = (ccache->mode & mask) ? 0 : KRB5_FCC_PERM;
 138
 139 out:
 140     if (ret) {
 141         kcm_log(2, "Process %d is not permitted to call %s on cache %s",
 142                 client->pid, kcm_op2string(opcode), ccache->name);
 143     }
 144
 145     return ret;
 146 }
 147
 148 krb5_error_code
 149 kcm_chmod(krb5_context context,
 150           kcm_client *client,
 151           kcm_ccache ccache,
 152           uint16_t mode)
 153 {
 154     KCM_ASSERT_VALID(ccache);
 155
 156     /* System cache mode can only be set at startup */
 157     if (ccache->flags & KCM_FLAGS_OWNER_IS_SYSTEM)
 158         return KRB5_FCC_PERM;
 159
 160     if (ccache->uid != client->uid)
 161         return KRB5_FCC_PERM;
 162
 163     if (ccache->gid != client->gid)
 164         return KRB5_FCC_PERM;
 165
 166     HEIMDAL_MUTEX_lock(&ccache->mutex);
 167
 168     ccache->mode = mode;
 169
 170     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 171
 172     return 0;
 173 }
 174
 175 krb5_error_code
 176 kcm_chown(krb5_context context,
 177           kcm_client *client,
 178           kcm_ccache ccache,
 179           uid_t uid,
 180           gid_t gid)
 181 {
 182     KCM_ASSERT_VALID(ccache);
 183
 184     /* System cache owner can only be set at startup */
 185     if (ccache->flags & KCM_FLAGS_OWNER_IS_SYSTEM)
 186         return KRB5_FCC_PERM;
 187
 188     if (ccache->uid != client->uid)
 189         return KRB5_FCC_PERM;
 190
 191     if (ccache->gid != client->gid)
 192         return KRB5_FCC_PERM;
 193
 194     HEIMDAL_MUTEX_lock(&ccache->mutex);
 195
 196     ccache->uid = uid;
 197     ccache->gid = gid;
 198
 199     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 200
 201     return 0;
 202 }
 203