1 /* $NetBSD: openpam_dispatch.c,v 1.4 2021/03/08 19:38:10 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 * $OpenPAM: openpam_dispatch.c 938 2017-04-30 21:34:42Z des $ 38 */ 39 40 #ifdef HAVE_CONFIG_H 41 # include "config.h" 42 #endif 43 44 #include <sys/cdefs.h> 45 __RCSID("$NetBSD: openpam_dispatch.c,v 1.4 2021/03/08 19:38:10 christos Exp $"); 46 47 #include <sys/param.h> 48 49 #include <stdint.h> 50 51 #include <security/pam_appl.h> 52 53 #include "openpam_impl.h" 54 55 #if !defined(OPENPAM_RELAX_CHECKS) 56 static void openpam_check_error_code(int, int); 57 #else 58 #define openpam_check_error_code(a, b) 59 #endif /* !defined(OPENPAM_RELAX_CHECKS) */ 60 61 /* 62 * OpenPAM internal 63 * 64 * Execute a module chain 65 */ 66 67 int 68 openpam_dispatch(pam_handle_t *pamh, 69 int primitive, 70 int flags) 71 { 72 pam_chain_t *chain; 73 int err, fail, nsuccess, r; 74 int debug; 75 76 ENTER(); 77 78 /* prevent recursion */ 79 if (pamh->current != NULL) { 80 openpam_log(PAM_LOG_ERROR, 81 "%s() called while %s::%s() is in progress", 82 pam_func_name[primitive], 83 pamh->current->module->path, 84 pam_sm_func_name[pamh->primitive]); 85 RETURNC(PAM_ABORT); 86 } 87 88 /* pick a chain */ 89 switch ((enum openpam_sm_primitives)primitive) { 90 case PAM_SM_AUTHENTICATE: 91 case PAM_SM_SETCRED: 92 chain = pamh->chains[PAM_AUTH]; 93 break; 94 case PAM_SM_ACCT_MGMT: 95 chain = pamh->chains[PAM_ACCOUNT]; 96 break; 97 case PAM_SM_OPEN_SESSION: 98 case PAM_SM_CLOSE_SESSION: 99 chain = pamh->chains[PAM_SESSION]; 100 break; 101 case PAM_SM_CHAUTHTOK: 102 chain = pamh->chains[PAM_PASSWORD]; 103 break; 104 case PAM_NUM_PRIMITIVES: 105 default: 106 RETURNC(PAM_SYSTEM_ERR); 107 } 108 109 /* execute */ 110 err = PAM_SUCCESS; 111 fail = nsuccess = 0; 112 for (; chain != NULL; chain = chain->next) { 113 if (chain->module->func[primitive] == NULL) { 114 openpam_log(PAM_LOG_ERROR, "%s: no %s()", 115 chain->module->path, pam_sm_func_name[primitive]); 116 r = PAM_SYMBOL_ERR; 117 } else { 118 pamh->primitive = primitive; 119 pamh->current = chain; 120 debug = (openpam_get_option(pamh, "debug") != NULL); 121 if (debug) 122 ++openpam_debug; 123 openpam_log(PAM_LOG_LIBDEBUG, "calling %s() in %s", 124 pam_sm_func_name[primitive], chain->module->path); 125 r = (chain->module->func[primitive])(pamh, flags, 126 chain->optc, (const char **)(intptr_t)chain->optv); 127 pamh->current = NULL; 128 openpam_log(PAM_LOG_LIBDEBUG, "%s: %s(): %s", 129 chain->module->path, pam_sm_func_name[primitive], 130 pam_strerror(pamh, r)); 131 if (debug) 132 --openpam_debug; 133 } 134 135 if (r == PAM_IGNORE) 136 continue; 137 if (r == PAM_SUCCESS) { 138 ++nsuccess; 139 /* 140 * For pam_setcred() and pam_chauthtok() with the 141 * PAM_PRELIM_CHECK flag, treat "sufficient" as 142 * "optional". 143 */ 144 if ((chain->flag == PAM_SUFFICIENT || 145 chain->flag == PAM_BINDING) && !fail && 146 primitive != PAM_SM_SETCRED && 147 !(primitive == PAM_SM_CHAUTHTOK && 148 (flags & PAM_PRELIM_CHECK))) 149 break; 150 continue; 151 } 152 153 openpam_check_error_code(primitive, r); 154 155 /* 156 * Record the return code from the first module to 157 * fail. If a required module fails, record the 158 * return code from the first required module to fail. 159 */ 160 if (err == PAM_SUCCESS) 161 err = r; 162 if ((chain->flag == PAM_REQUIRED || 163 chain->flag == PAM_BINDING) && !fail) { 164 openpam_log(PAM_LOG_LIBDEBUG, "required module failed"); 165 fail = 1; 166 err = r; 167 } 168 169 /* 170 * If a requisite module fails, terminate the chain 171 * immediately. 172 */ 173 if (chain->flag == PAM_REQUISITE) { 174 openpam_log(PAM_LOG_LIBDEBUG, "requisite module failed"); 175 fail = 1; 176 break; 177 } 178 } 179 180 if (!fail && err != PAM_NEW_AUTHTOK_REQD) 181 err = PAM_SUCCESS; 182 183 /* 184 * Require the chain to be non-empty, and at least one module 185 * in the chain to be successful, so that we don't fail open. 186 */ 187 if (err == PAM_SUCCESS && nsuccess < 1) { 188 openpam_log(PAM_LOG_ERROR, 189 "all modules were unsuccessful for %s()", 190 pam_sm_func_name[primitive]); 191 err = PAM_SYSTEM_ERR; 192 } 193 194 RETURNC(err); 195 } 196 197 #if !defined(OPENPAM_RELAX_CHECKS) 198 static void 199 openpam_check_error_code(int primitive, int r) 200 { 201 /* common error codes */ 202 if (r == PAM_SUCCESS || 203 r == PAM_SYSTEM_ERR || 204 r == PAM_SERVICE_ERR || 205 r == PAM_BUF_ERR || 206 r == PAM_CONV_ERR || 207 r == PAM_PERM_DENIED || 208 r == PAM_ABORT) 209 return; 210 211 /* specific error codes */ 212 switch ((enum openpam_sm_primitives)primitive) { 213 case PAM_SM_AUTHENTICATE: 214 if (r == PAM_AUTH_ERR || 215 r == PAM_CRED_INSUFFICIENT || 216 r == PAM_AUTHINFO_UNAVAIL || 217 r == PAM_USER_UNKNOWN || 218 r == PAM_MAXTRIES) 219 return; 220 break; 221 case PAM_SM_SETCRED: 222 if (r == PAM_CRED_UNAVAIL || 223 r == PAM_CRED_EXPIRED || 224 r == PAM_USER_UNKNOWN || 225 r == PAM_CRED_ERR) 226 return; 227 break; 228 case PAM_SM_ACCT_MGMT: 229 if (r == PAM_USER_UNKNOWN || 230 r == PAM_AUTH_ERR || 231 r == PAM_NEW_AUTHTOK_REQD || 232 r == PAM_ACCT_EXPIRED) 233 return; 234 break; 235 case PAM_SM_OPEN_SESSION: 236 case PAM_SM_CLOSE_SESSION: 237 if (r == PAM_SESSION_ERR) 238 return; 239 break; 240 case PAM_SM_CHAUTHTOK: 241 if (r == PAM_PERM_DENIED || 242 r == PAM_AUTHTOK_ERR || 243 r == PAM_AUTHTOK_RECOVERY_ERR || 244 r == PAM_AUTHTOK_LOCK_BUSY || 245 r == PAM_AUTHTOK_DISABLE_AGING || 246 r == PAM_TRY_AGAIN) 247 return; 248 break; 249 case PAM_NUM_PRIMITIVES: 250 break; 251 } 252 253 openpam_log(PAM_LOG_ERROR, "%s(): unexpected return value %d", 254 pam_sm_func_name[primitive], r); 255 } 256 #endif /* !defined(OPENPAM_RELAX_CHECKS) */ 257 258 /* 259 * NODOC 260 * 261 * Error codes: 262 */ 263