1 /* $NetBSD: openpam_dispatch.c,v 1.5 2023/06/30 21:46:20 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2002-2003 Networks Associates Technology, Inc. 5 * Copyright (c) 2004-2017 Dag-Erling Smørgrav 6 * All rights reserved. 7 * 8 * This software was developed for the FreeBSD Project by ThinkSec AS and 9 * Network Associates Laboratories, the Security Research Division of 10 * Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 11 * ("CBOSS"), as part of the DARPA CHATS research program. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. The name of the author may not be used to endorse or promote 22 * products derived from this software without specific prior written 23 * permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #ifdef HAVE_CONFIG_H 39 # include "config.h" 40 #endif 41 42 #include <sys/cdefs.h> 43 __RCSID("$NetBSD: openpam_dispatch.c,v 1.5 2023/06/30 21:46:20 christos Exp $"); 44 45 #include <sys/param.h> 46 47 #include <stdint.h> 48 49 #include <security/pam_appl.h> 50 51 #include "openpam_impl.h" 52 53 #if !defined(OPENPAM_RELAX_CHECKS) 54 static void openpam_check_error_code(int, int); 55 #else 56 #define openpam_check_error_code(a, b) 57 #endif /* !defined(OPENPAM_RELAX_CHECKS) */ 58 59 /* 60 * OpenPAM internal 61 * 62 * Execute a module chain 63 */ 64 65 int 66 openpam_dispatch(pam_handle_t *pamh, 67 int primitive, 68 int flags) 69 { 70 pam_chain_t *chain; 71 int err, fail, nsuccess, r; 72 int debug; 73 74 ENTER(); 75 76 /* prevent recursion */ 77 if (pamh->current != NULL) { 78 openpam_log(PAM_LOG_ERROR, 79 "%s() called while %s::%s() is in progress", 80 pam_func_name[primitive], 81 pamh->current->module->path, 82 pam_sm_func_name[pamh->primitive]); 83 RETURNC(PAM_ABORT); 84 } 85 86 /* pick a chain */ 87 switch ((enum openpam_sm_primitives)primitive) { 88 case PAM_SM_AUTHENTICATE: 89 case PAM_SM_SETCRED: 90 chain = pamh->chains[PAM_AUTH]; 91 break; 92 case PAM_SM_ACCT_MGMT: 93 chain = pamh->chains[PAM_ACCOUNT]; 94 break; 95 case PAM_SM_OPEN_SESSION: 96 case PAM_SM_CLOSE_SESSION: 97 chain = pamh->chains[PAM_SESSION]; 98 break; 99 case PAM_SM_CHAUTHTOK: 100 chain = pamh->chains[PAM_PASSWORD]; 101 break; 102 case PAM_NUM_PRIMITIVES: 103 default: 104 RETURNC(PAM_SYSTEM_ERR); 105 } 106 107 /* execute */ 108 err = PAM_SUCCESS; 109 fail = nsuccess = 0; 110 for (; chain != NULL; chain = chain->next) { 111 if (chain->module->func[primitive] == NULL) { 112 openpam_log(PAM_LOG_ERROR, "%s: no %s()", 113 chain->module->path, pam_sm_func_name[primitive]); 114 r = PAM_SYMBOL_ERR; 115 } else { 116 pamh->primitive = primitive; 117 pamh->current = chain; 118 debug = (openpam_get_option(pamh, "debug") != NULL); 119 if (debug) 120 ++openpam_debug; 121 openpam_log(PAM_LOG_LIBDEBUG, "calling %s() in %s", 122 pam_sm_func_name[primitive], chain->module->path); 123 r = (chain->module->func[primitive])(pamh, flags, 124 chain->optc, (const char **)(intptr_t)chain->optv); 125 pamh->current = NULL; 126 openpam_log(PAM_LOG_LIBDEBUG, "%s: %s(): %s", 127 chain->module->path, pam_sm_func_name[primitive], 128 pam_strerror(pamh, r)); 129 if (debug) 130 --openpam_debug; 131 } 132 133 if (r == PAM_IGNORE) 134 continue; 135 if (r == PAM_SUCCESS) { 136 ++nsuccess; 137 /* 138 * For pam_setcred() and pam_chauthtok() with the 139 * PAM_PRELIM_CHECK flag, treat "sufficient" as 140 * "optional". 141 */ 142 if ((chain->flag == PAM_SUFFICIENT || 143 chain->flag == PAM_BINDING) && !fail && 144 primitive != PAM_SM_SETCRED && 145 !(primitive == PAM_SM_CHAUTHTOK && 146 (flags & PAM_PRELIM_CHECK))) 147 break; 148 continue; 149 } 150 151 openpam_check_error_code(primitive, r); 152 153 /* 154 * Record the return code from the first module to 155 * fail. If a required module fails, record the 156 * return code from the first required module to fail. 157 */ 158 if (err == PAM_SUCCESS) 159 err = r; 160 if ((chain->flag == PAM_REQUIRED || 161 chain->flag == PAM_BINDING) && !fail) { 162 openpam_log(PAM_LOG_LIBDEBUG, "required module failed"); 163 fail = 1; 164 err = r; 165 } 166 167 /* 168 * If a requisite module fails, terminate the chain 169 * immediately. 170 */ 171 if (chain->flag == PAM_REQUISITE) { 172 openpam_log(PAM_LOG_LIBDEBUG, "requisite module failed"); 173 fail = 1; 174 break; 175 } 176 } 177 178 if (!fail && err != PAM_NEW_AUTHTOK_REQD) 179 err = PAM_SUCCESS; 180 181 /* 182 * Require the chain to be non-empty, and at least one module 183 * in the chain to be successful, so that we don't fail open. 184 */ 185 if (err == PAM_SUCCESS && nsuccess < 1) { 186 openpam_log(PAM_LOG_ERROR, 187 "all modules were unsuccessful for %s()", 188 pam_sm_func_name[primitive]); 189 err = PAM_SYSTEM_ERR; 190 } 191 192 RETURNC(err); 193 } 194 195 #if !defined(OPENPAM_RELAX_CHECKS) 196 static void 197 openpam_check_error_code(int primitive, int r) 198 { 199 /* common error codes */ 200 if (r == PAM_SUCCESS || 201 r == PAM_SYSTEM_ERR || 202 r == PAM_SERVICE_ERR || 203 r == PAM_BUF_ERR || 204 r == PAM_CONV_ERR || 205 r == PAM_PERM_DENIED || 206 r == PAM_ABORT) 207 return; 208 209 /* specific error codes */ 210 switch ((enum openpam_sm_primitives)primitive) { 211 case PAM_SM_AUTHENTICATE: 212 if (r == PAM_AUTH_ERR || 213 r == PAM_CRED_INSUFFICIENT || 214 r == PAM_AUTHINFO_UNAVAIL || 215 r == PAM_USER_UNKNOWN || 216 r == PAM_MAXTRIES) 217 return; 218 break; 219 case PAM_SM_SETCRED: 220 if (r == PAM_CRED_UNAVAIL || 221 r == PAM_CRED_EXPIRED || 222 r == PAM_USER_UNKNOWN || 223 r == PAM_CRED_ERR) 224 return; 225 break; 226 case PAM_SM_ACCT_MGMT: 227 if (r == PAM_USER_UNKNOWN || 228 r == PAM_AUTH_ERR || 229 r == PAM_NEW_AUTHTOK_REQD || 230 r == PAM_ACCT_EXPIRED) 231 return; 232 break; 233 case PAM_SM_OPEN_SESSION: 234 case PAM_SM_CLOSE_SESSION: 235 if (r == PAM_SESSION_ERR) 236 return; 237 break; 238 case PAM_SM_CHAUTHTOK: 239 if (r == PAM_PERM_DENIED || 240 r == PAM_AUTHTOK_ERR || 241 r == PAM_AUTHTOK_RECOVERY_ERR || 242 r == PAM_AUTHTOK_LOCK_BUSY || 243 r == PAM_AUTHTOK_DISABLE_AGING || 244 r == PAM_TRY_AGAIN) 245 return; 246 break; 247 case PAM_NUM_PRIMITIVES: 248 break; 249 } 250 251 openpam_log(PAM_LOG_ERROR, "%s(): unexpected return value %d", 252 pam_sm_func_name[primitive], r); 253 } 254 #endif /* !defined(OPENPAM_RELAX_CHECKS) */ 255 256 /* 257 * NODOC 258 * 259 * Error codes: 260 */ 261