acl.c revision 72445
1/* 2 * Copyright (c) 1997 - 2000 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include "kadm5_locl.h" 35 36RCSID("$Id: acl.c,v 1.12 2000/08/10 19:24:08 assar Exp $"); 37 38static struct units acl_units[] = { 39 { "all", KADM5_PRIV_ALL }, 40 { "change-password",KADM5_PRIV_CPW }, 41 { "cpw", KADM5_PRIV_CPW }, 42 { "list", KADM5_PRIV_LIST }, 43 { "delete", KADM5_PRIV_DELETE }, 44 { "modify", KADM5_PRIV_MODIFY }, 45 { "add", KADM5_PRIV_ADD }, 46 { "get", KADM5_PRIV_GET }, 47 { NULL } 48}; 49 50kadm5_ret_t 51_kadm5_string_to_privs(const char *s, u_int32_t* privs) 52{ 53 int flags; 54 flags = parse_flags(s, acl_units, 0); 55 if(flags < 0) 56 return KADM5_FAILURE; 57 *privs = flags; 58 return 0; 59} 60 61kadm5_ret_t 62_kadm5_privs_to_string(u_int32_t privs, char *string, size_t len) 63{ 64 if(privs == 0) 65 strlcpy(string, "none", len); 66 else 67 unparse_flags(privs, acl_units + 1, string, len); 68 return 0; 69} 70 71/* 72 * retrieve the right for the current caller on `princ' (NULL means all) 73 * and store them in `ret_flags' 74 * return 0 or an error. 75 */ 76 77static kadm5_ret_t 78fetch_acl (kadm5_server_context *context, 79 krb5_const_principal princ, 80 unsigned *ret_flags) 81{ 82 unsigned flags = -1; 83 FILE *f = fopen(context->config.acl_file, "r"); 84 krb5_error_code ret = 0; 85 86 if(f != NULL) { 87 char buf[256]; 88 89 while(fgets(buf, sizeof(buf), f) != NULL){ 90 char *foo = NULL, *p; 91 krb5_principal this_princ; 92 93 flags = -1; 94 p = strtok_r(buf, " \t\n", &foo); 95 if(p == NULL) 96 continue; 97 ret = krb5_parse_name(context->context, p, &this_princ); 98 if(ret) 99 continue; 100 if(!krb5_principal_compare(context->context, 101 context->caller, this_princ)) { 102 krb5_free_principal(context->context, this_princ); 103 continue; 104 } 105 krb5_free_principal(context->context, this_princ); 106 p = strtok_r(NULL, " \t\n", &foo); 107 if(p == NULL) 108 continue; 109 ret = _kadm5_string_to_privs(p, &flags); 110 if (ret) 111 break; 112 p = strtok_r(NULL, "\n", &foo); 113 if (p == NULL) { 114 ret = 0; 115 break; 116 } 117 if (princ != NULL) { 118 krb5_principal pattern_princ; 119 krb5_boolean tmp; 120 121 ret = krb5_parse_name (context->context, p, &pattern_princ); 122 if (ret) 123 break; 124 tmp = krb5_principal_match (context->context, 125 princ, pattern_princ); 126 krb5_free_principal (context->context, pattern_princ); 127 if (tmp) { 128 ret = 0; 129 break; 130 } 131 } 132 } 133 fclose(f); 134 } 135 if(flags == -1) 136 flags = 0; 137 if (ret == 0) 138 *ret_flags = flags; 139 return ret; 140} 141 142/* 143 * set global acl flags in `context' for the current caller. 144 * return 0 on success or an error 145 */ 146 147kadm5_ret_t 148_kadm5_acl_init(kadm5_server_context *context) 149{ 150 krb5_principal princ; 151 krb5_error_code ret; 152 153 ret = krb5_parse_name(context->context, KADM5_ADMIN_SERVICE, &princ); 154 if (ret) 155 return ret; 156 ret = krb5_principal_compare(context->context, context->caller, princ); 157 krb5_free_principal(context->context, princ); 158 if(ret != 0) { 159 context->acl_flags = KADM5_PRIV_ALL; 160 return 0; 161 } 162 163 return fetch_acl (context, NULL, &context->acl_flags); 164} 165 166/* 167 * check if `flags' allows `op' 168 * return 0 if OK or an error 169 */ 170 171static kadm5_ret_t 172check_flags (unsigned op, 173 unsigned flags) 174{ 175 unsigned res = ~flags & op; 176 177 if(res & KADM5_PRIV_GET) 178 return KADM5_AUTH_GET; 179 if(res & KADM5_PRIV_ADD) 180 return KADM5_AUTH_ADD; 181 if(res & KADM5_PRIV_MODIFY) 182 return KADM5_AUTH_MODIFY; 183 if(res & KADM5_PRIV_DELETE) 184 return KADM5_AUTH_DELETE; 185 if(res & KADM5_PRIV_CPW) 186 return KADM5_AUTH_CHANGEPW; 187 if(res & KADM5_PRIV_LIST) 188 return KADM5_AUTH_LIST; 189 if(res) 190 return KADM5_AUTH_INSUFFICIENT; 191 return 0; 192} 193 194/* 195 * return 0 if the current caller in `context' is allowed to perform 196 * `op' on `princ' and otherwise an error 197 * princ == NULL if it's not relevant. 198 */ 199 200kadm5_ret_t 201_kadm5_acl_check_permission(kadm5_server_context *context, 202 unsigned op, 203 krb5_const_principal princ) 204{ 205 kadm5_ret_t ret; 206 unsigned princ_flags; 207 208 ret = check_flags (op, context->acl_flags); 209 if (ret == 0) 210 return ret; 211 ret = fetch_acl (context, princ, &princ_flags); 212 if (ret) 213 return ret; 214 return check_flags (op, princ_flags); 215} 216