1 /* $NetBSD: client.c,v 1.3 2017/09/08 15:29:43 christos 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 #include <pwd.h> 39 40 krb5_error_code 41 kcm_ccache_resolve_client(krb5_context context, 42 kcm_client *client, 43 kcm_operation opcode, 44 const char *name, 45 kcm_ccache *ccache) 46 { 47 krb5_error_code ret; 48 const char *estr; 49 50 ret = kcm_ccache_resolve(context, name, ccache); 51 if (ret) { 52 estr = krb5_get_error_message(context, ret); 53 kcm_log(1, "Failed to resolve cache %s: %s", name, estr); 54 krb5_free_error_message(context, estr); 55 return ret; 56 } 57 58 ret = kcm_access(context, client, opcode, *ccache); 59 if (ret) { 60 ret = KRB5_FCC_NOFILE; /* don't disclose */ 61 kcm_release_ccache(context, *ccache); 62 } 63 64 return ret; 65 } 66 67 krb5_error_code 68 kcm_ccache_destroy_client(krb5_context context, 69 kcm_client *client, 70 const char *name) 71 { 72 krb5_error_code ret; 73 kcm_ccache ccache; 74 const char *estr; 75 76 ret = kcm_ccache_resolve(context, name, &ccache); 77 if (ret) { 78 estr = krb5_get_error_message(context, ret); 79 kcm_log(1, "Failed to resolve cache %s: %s", name, estr); 80 krb5_free_error_message(context, estr); 81 return ret; 82 } 83 84 ret = kcm_access(context, client, KCM_OP_DESTROY, ccache); 85 kcm_cleanup_events(context, ccache); 86 kcm_release_ccache(context, ccache); 87 if (ret) 88 return ret; 89 90 return kcm_ccache_destroy(context, name); 91 } 92 93 krb5_error_code 94 kcm_ccache_new_client(krb5_context context, 95 kcm_client *client, 96 const char *name, 97 kcm_ccache *ccache_p) 98 { 99 krb5_error_code ret; 100 kcm_ccache ccache; 101 const char *estr; 102 103 /* We insist the ccache name starts with UID or UID: */ 104 if (name_constraints != 0) { 105 char prefix[64]; 106 size_t prefix_len; 107 int bad = 1; 108 109 snprintf(prefix, sizeof(prefix), "%ld:", (long)client->uid); 110 prefix_len = strlen(prefix); 111 112 if (strncmp(name, prefix, prefix_len) == 0) 113 bad = 0; 114 else { 115 prefix[prefix_len - 1] = '\0'; 116 if (strcmp(name, prefix) == 0) 117 bad = 0; 118 } 119 120 /* Allow root to create badly-named ccaches */ 121 if (bad && !CLIENT_IS_ROOT(client)) 122 return KRB5_CC_BADNAME; 123 } 124 125 ret = kcm_ccache_resolve(context, name, &ccache); 126 if (ret == 0) { 127 if ((ccache->uid != client->uid || 128 ccache->gid != client->gid) && !CLIENT_IS_ROOT(client)) 129 return KRB5_FCC_PERM; 130 } else if (ret != KRB5_FCC_NOFILE && !(CLIENT_IS_ROOT(client) && ret == KRB5_FCC_PERM)) { 131 return ret; 132 } 133 134 if (ret == KRB5_FCC_NOFILE) { 135 ret = kcm_ccache_new(context, name, &ccache); 136 if (ret) { 137 estr = krb5_get_error_message(context, ret); 138 kcm_log(1, "Failed to initialize cache %s: %s", name, estr); 139 krb5_free_error_message(context, estr); 140 return ret; 141 } 142 143 /* bind to current client */ 144 ccache->uid = client->uid; 145 ccache->gid = client->gid; 146 ccache->session = client->session; 147 } else { 148 ret = kcm_zero_ccache_data(context, ccache); 149 if (ret) { 150 estr = krb5_get_error_message(context, ret); 151 kcm_log(1, "Failed to empty cache %s: %s", name, estr); 152 krb5_free_error_message(context, estr); 153 kcm_release_ccache(context, ccache); 154 return ret; 155 } 156 kcm_cleanup_events(context, ccache); 157 } 158 159 ret = kcm_access(context, client, KCM_OP_INITIALIZE, ccache); 160 if (ret) { 161 kcm_release_ccache(context, ccache); 162 kcm_ccache_destroy(context, name); 163 return ret; 164 } 165 166 /* 167 * Finally, if the user is root and the cache was created under 168 * another user's name, chown the cache to that user and their 169 * default gid. 170 */ 171 if (CLIENT_IS_ROOT(client)) { 172 unsigned long uid; 173 int matches = sscanf(name,"%ld:",&uid); 174 if (matches == 0) 175 matches = sscanf(name,"%ld",&uid); 176 if (matches == 1) { 177 struct passwd pw, *pwd = NULL; 178 char pwbuf[2048]; 179 180 if (rk_getpwuid_r(getuid(), &pw, pwbuf, sizeof(pwbuf), &pwd) == 0) { 181 gid_t gid = pwd->pw_gid; 182 kcm_chown(context, client, ccache, uid, gid); 183 } 184 } 185 } 186 187 *ccache_p = ccache; 188 return 0; 189 } 190 191