crypto/dist/heimdal/kcm/client.c

   1 /*
   2  * Copyright (c) 2005, PADL Software Pty Ltd.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of PADL Software nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "kcm_locl.h"
  34 #include <pwd.h>
  35
  36 __RCSID("$Heimdal: client.c 20487 2007-04-21 06:25:06Z lha $"
  37         "$NetBSD$");
  38
  39 krb5_error_code
  40 kcm_ccache_resolve_client(krb5_context context,
  41                           kcm_client *client,
  42                           kcm_operation opcode,
  43                           const char *name,
  44                           kcm_ccache *ccache)
  45 {
  46     krb5_error_code ret;
  47
  48     ret = kcm_ccache_resolve(context, name, ccache);
  49     if (ret) {
  50         kcm_log(1, "Failed to resolve cache %s: %s",
  51                 name, krb5_get_err_text(context, ret));
  52         return ret;
  53     }
  54
  55     ret = kcm_access(context, client, opcode, *ccache);
  56     if (ret) {
  57         ret = KRB5_FCC_NOFILE; /* don't disclose */
  58         kcm_release_ccache(context, ccache);
  59     }
  60
  61     return ret;
  62 }
  63
  64 krb5_error_code
  65 kcm_ccache_destroy_client(krb5_context context,
  66                           kcm_client *client,
  67                           const char *name)
  68 {
  69     krb5_error_code ret;
  70     kcm_ccache ccache;
  71
  72     ret = kcm_ccache_resolve(context, name, &ccache);
  73     if (ret) {
  74         kcm_log(1, "Failed to resolve cache %s: %s",
  75                 name, krb5_get_err_text(context, ret));
  76         return ret;
  77     }
  78
  79     ret = kcm_access(context, client, KCM_OP_DESTROY, ccache);
  80     if (ret) {
  81         kcm_release_ccache(context, &ccache);
  82         return ret;
  83     }
  84
  85     ret = kcm_ccache_destroy(context, ccache->name);
  86     if (ret == 0) {
  87         /* don't leave any events dangling */
  88         kcm_cleanup_events(context, ccache);
  89     }
  90
  91     kcm_release_ccache(context, &ccache);
  92     return ret;
  93 }
  94
  95 krb5_error_code
  96 kcm_ccache_new_client(krb5_context context,
  97                       kcm_client *client,
  98                       const char *name,
  99                       kcm_ccache *ccache_p)
 100 {
 101     krb5_error_code ret;
 102     kcm_ccache ccache;
 103
 104     /* We insist the ccache name starts with UID or UID: */
 105     if (name_constraints != 0) {
 106         char prefix[64];
 107         size_t prefix_len;
 108         int bad = 1;
 109
 110         snprintf(prefix, sizeof(prefix), "%ld:", (long)client->uid);
 111         prefix_len = strlen(prefix);
 112
 113         if (strncmp(name, prefix, prefix_len) == 0)
 114             bad = 0;
 115         else {
 116             prefix[prefix_len - 1] = '\0';
 117             if (strcmp(name, prefix) == 0)
 118                 bad = 0;
 119         }
 120
 121         /* Allow root to create badly-named ccaches */
 122         if (bad && !CLIENT_IS_ROOT(client))
 123             return KRB5_CC_BADNAME;
 124     }
 125
 126     ret = kcm_ccache_resolve(context, name, &ccache);
 127     if (ret == 0) {
 128         if ((ccache->uid != client->uid ||
 129              ccache->gid != client->gid) && !CLIENT_IS_ROOT(client))
 130             return KRB5_FCC_PERM;
 131     } else if (ret != KRB5_FCC_NOFILE && !(CLIENT_IS_ROOT(client) && ret == KRB5_FCC_PERM)) {
 132                 return ret;
 133     }
 134
 135     if (ret == KRB5_FCC_NOFILE) {
 136         ret = kcm_ccache_new(context, name, &ccache);
 137         if (ret) {
 138             kcm_log(1, "Failed to initialize cache %s: %s",
 139                     name, krb5_get_err_text(context, ret));
 140             return ret;
 141         }
 142
 143         /* bind to current client */
 144         ccache->uid = client->uid;
 145         ccache->gid = client->gid;
 146     } else {
 147         ret = kcm_zero_ccache_data(context, ccache);
 148         if (ret) {
 149             kcm_log(1, "Failed to empty cache %s: %s",
 150                     name, krb5_get_err_text(context, ret));
 151             kcm_release_ccache(context, &ccache);
 152             return ret;
 153         }
 154         kcm_cleanup_events(context, ccache);
 155     }
 156
 157     ret = kcm_access(context, client, KCM_OP_INITIALIZE, ccache);
 158     if (ret) {
 159         kcm_release_ccache(context, &ccache);
 160         kcm_ccache_destroy(context, name);
 161         return ret;
 162     }
 163
 164     /*
 165      * Finally, if the user is root and the cache was created under
 166      * another user's name, chown the cache to that user and their
 167      * default gid.
 168      */
 169     if (CLIENT_IS_ROOT(client)) {
 170         unsigned long uid;
 171         int matches = sscanf(name,"%ld:",&uid);
 172         if (matches == 0)
 173             matches = sscanf(name,"%ld",&uid);
 174         if (matches == 1) {
 175             struct passwd *pwd = getpwuid(uid);
 176             if (pwd != NULL) {
 177                 gid_t gid = pwd->pw_gid;
 178                 kcm_chown(context, client, ccache, uid, gid);
 179             }
 180         }
 181     }
 182
 183     *ccache_p = ccache;
 184     return 0;
 185 }
 186