1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 27 #include <stdlib.h> 28 #include <pwd.h> 29 #include <shadow.h> 30 #include <syslog.h> 31 #include <errno.h> 32 #include <string.h> 33 #include <crypt.h> 34 #include <unistd.h> 35 #include <user_attr.h> 36 #include <auth_attr.h> 37 #include <userdefs.h> 38 #include <deflt.h> 39 #include <sys/stat.h> 40 #include <sys/param.h> 41 #include <stdarg.h> 42 43 #include <security/pam_appl.h> 44 #include <security/pam_modules.h> 45 #include <security/pam_impl.h> 46 47 #include <libintl.h> 48 49 #include <passwdutil.h> 50 51 #define LOGINADMIN "/etc/default/login" 52 #define MAXTRYS 5 53 54 /*PRINTFLIKE2*/ 55 void 56 error(pam_handle_t *pamh, char *fmt, ...) 57 { 58 va_list ap; 59 char messages[1][PAM_MAX_MSG_SIZE]; 60 61 va_start(ap, fmt); 62 (void) vsnprintf(messages[0], sizeof (messages[0]), fmt, ap); 63 (void) __pam_display_msg(pamh, PAM_ERROR_MSG, 1, messages, NULL); 64 va_end(ap); 65 } 66 67 static int 68 get_max_failed(char *user) 69 { 70 char *val = NULL; 71 userattr_t *uattr; 72 int do_lock = 0; 73 int retval = 0; 74 char *p; 75 76 if ((uattr = getusernam(user)) != NULL) 77 val = kva_match(uattr->attr, USERATTR_LOCK_AFTER_RETRIES_KW); 78 79 if (val != NULL) 80 do_lock = (strcasecmp(val, "yes") == 0); 81 else if (defopen(AUTH_POLICY) == 0) { 82 int flags; 83 flags = defcntl(DC_GETFLAGS, 0); 84 TURNOFF(flags, DC_CASE); 85 (void) defcntl(DC_SETFLAGS, flags); 86 if ((p = defread("LOCK_AFTER_RETRIES=")) != NULL) 87 do_lock = (strcasecmp(p, "yes") == 0); 88 (void) defopen(NULL); 89 } 90 91 if (uattr != NULL) 92 free_userattr(uattr); 93 94 if (do_lock) { 95 retval = MAXTRYS; 96 if (defopen(LOGINADMIN) == 0) { 97 if ((p = defread("RETRIES=")) != NULL) 98 retval = atoi(p); 99 (void) defopen(NULL); 100 } 101 } 102 103 return (retval); 104 } 105 106 static void 107 display_warning(pam_handle_t *pamh, int failures, char *homedir) 108 { 109 char hushpath[MAXPATHLEN]; 110 struct stat buf; 111 112 (void) snprintf(hushpath, sizeof (hushpath), "%s/.hushlogin", homedir); 113 if (stat(hushpath, &buf) == 0) 114 return; 115 116 if (failures == 1) 117 error(pamh, "Warning: 1 failed login attempt since last " 118 "successful login."); 119 else if (failures < FAILCOUNT_MASK) 120 error(pamh, "Warning: %d failed login attempts since last " 121 "successful login.", failures); 122 else 123 error(pamh, "Warning: at least %d failed login attempts since " 124 "last successful login.", failures); 125 } 126 127 /* 128 * int pam_sm_authenticate(pamh, flags, arc, argv) 129 * 130 * This routine verifies that the password as stored in the 131 * PAM_AUTHTOK item is indeed the password that belongs to the user 132 * as stored in PAM_USER. 133 * 134 * This routine will not establish Secure RPC Credentials. If these 135 * credentials are needed to obtain the password from the NIS+ service, 136 * the pam_dhkeys module should be stacked before us! 137 */ 138 int 139 pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv) 140 { 141 int i; 142 int debug = 0; 143 int nowarn = (flags & PAM_SILENT) != 0; 144 char messages[PAM_MAX_NUM_MSG][PAM_MAX_MSG_SIZE]; 145 char *user; 146 char *passwd; 147 char *rep_passwd; 148 char *crypt_passwd; 149 char *repository_name; 150 struct pam_repository *auth_rep; 151 pwu_repository_t *pwu_rep; 152 attrlist attr_pw[4]; 153 int result; 154 int server_policy = 0; 155 int old_failed_count; 156 char *homedir = NULL; 157 int dolock = 1; 158 159 for (i = 0; i < argc; i++) { 160 if (strcmp(argv[i], "debug") == 0) 161 debug = 1; 162 else if (strcmp(argv[i], "nowarn") == 0) 163 nowarn = 1; 164 else if (strcmp(argv[i], "server_policy") == 0) 165 server_policy = 1; 166 else if (strcmp(argv[i], "nolock") == 0) 167 dolock = 0; 168 } 169 170 if (debug) 171 __pam_log(LOG_AUTH | LOG_DEBUG, 172 "pam_unix_auth: entering pam_sm_authenticate()"); 173 174 if (pam_get_item(pamh, PAM_USER, (void **)&user) != PAM_SUCCESS) { 175 __pam_log(LOG_AUTH | LOG_DEBUG, "pam_unix_auth: USER not set"); 176 return (PAM_SYSTEM_ERR); 177 } 178 179 if (user == NULL || *user == '\0') { 180 __pam_log(LOG_AUTH | LOG_DEBUG, 181 "pam_unix_auth: USER NULL or empty!\n"); 182 return (PAM_USER_UNKNOWN); 183 } 184 185 if (pam_get_item(pamh, PAM_AUTHTOK, (void **)&passwd) != PAM_SUCCESS) { 186 __pam_log(LOG_AUTH | LOG_DEBUG, 187 "pam_unix_auth: AUTHTOK not set!\n"); 188 return (PAM_SYSTEM_ERR); 189 } 190 191 result = pam_get_item(pamh, PAM_REPOSITORY, (void **)&auth_rep); 192 if (result == PAM_SUCCESS && auth_rep != NULL) { 193 if ((pwu_rep = calloc(1, sizeof (*pwu_rep))) == NULL) 194 return (PAM_BUF_ERR); 195 pwu_rep->type = auth_rep->type; 196 pwu_rep->scope = auth_rep->scope; 197 pwu_rep->scope_len = auth_rep->scope_len; 198 } else { 199 pwu_rep = PWU_DEFAULT_REP; 200 } 201 202 /* 203 * Get password and the name of the repository where the 204 * password resides. 205 */ 206 attr_pw[0].type = ATTR_PASSWD; attr_pw[0].next = &attr_pw[1]; 207 attr_pw[1].type = ATTR_REP_NAME; attr_pw[1].next = &attr_pw[2]; 208 /* 209 * Also get the current number of failed logins; we use 210 * this later to determine whether we need to reset the count 211 * on a succesful authentication. We use the home-directory 212 * to look for .hushlogin in order to optionaly surpress the 213 * "failed attempts" message. 214 */ 215 attr_pw[2].type = ATTR_FAILED_LOGINS; attr_pw[2].next = &attr_pw[3]; 216 attr_pw[3].type = ATTR_HOMEDIR; attr_pw[3].next = NULL; 217 218 result = __get_authtoken_attr(user, pwu_rep, attr_pw); 219 220 if (pwu_rep != PWU_DEFAULT_REP) 221 free(pwu_rep); 222 223 if (result == PWU_NOT_FOUND) { 224 __pam_log(LOG_AUTH | LOG_DEBUG, 225 "pam_unix_auth: user %s not found\n", user); 226 return (PAM_USER_UNKNOWN); 227 } 228 229 if (result == PWU_DENIED) { 230 __pam_log(LOG_AUTH | LOG_DEBUG, 231 "pam_unix_auth: failed to obtain attributes"); 232 return (PAM_PERM_DENIED); 233 } 234 235 if (result != PWU_SUCCESS) 236 return (PAM_SYSTEM_ERR); 237 238 rep_passwd = attr_pw[0].data.val_s; 239 repository_name = attr_pw[1].data.val_s; 240 old_failed_count = attr_pw[2].data.val_i; 241 homedir = attr_pw[3].data.val_s; 242 243 /* 244 * Chop off old SunOS-style password aging information. 245 * 246 * Note: old style password aging is only defined for UNIX-style 247 * crypt strings, hence the comma will always be at position 14. 248 * Note: This code is here because some other vendors might still 249 * support this style of password aging. If we don't remove 250 * the age field, no one will be able to login. 251 * XXX yank this code when we're certain this "compatibility" 252 * isn't needed anymore. 253 */ 254 if (rep_passwd != NULL && rep_passwd[0] != '$' && 255 strlen(rep_passwd) > 13 && rep_passwd[13] == ',') 256 rep_passwd[13] = '\0'; 257 258 /* Is a password check required? */ 259 if (rep_passwd == NULL || *rep_passwd == '\0') { 260 if (flags & PAM_DISALLOW_NULL_AUTHTOK) { 261 result = PAM_AUTH_ERR; 262 __pam_log(LOG_AUTH | LOG_NOTICE, 263 "pam_unix_auth: empty password for %s not allowed.", 264 user); 265 goto out; 266 } else { 267 result = PAM_SUCCESS; 268 goto out; 269 } 270 } 271 272 /* 273 * Password check *is* required. Make sure we have a valid 274 * pointer in PAM_AUTHTOK 275 */ 276 if (passwd == NULL) { 277 result = PAM_AUTH_ERR; 278 goto out; 279 } 280 281 /* 282 * "rep_passwd" holds the encrypted password. 283 * If, however, we detect that the password equals NOPWDRTR, 284 * while we've obtained it from NIS+, it 285 * means that the permissions on the NIS+ table are too tight 286 * for us to get the password without having Secure RPC 287 * Credentials. In that case, we log an error stating that 288 * the Secure RPC credential Module should be on the PAM stack 289 * before the unix_auth module. We also tell the user to go 290 * and inform the administrator of this error. 291 */ 292 if (strcmp(repository_name, "nisplus") == 0 && 293 strcmp(rep_passwd, NOPWDRTR) == 0) { 294 __pam_log(LOG_AUTH | LOG_ERR, 295 "pam_unix_auth: NIS+ permissions require that" 296 "the pam_dhkeys module is on the PAM stack before " 297 "pam_unix_auth"); 298 if (nowarn == 0) { 299 (void) snprintf(messages[0], sizeof (messages[0]), 300 dgettext(TEXT_DOMAIN, 301 "NIS+ permissions are too tight. " 302 "Please inform your administrator.")); 303 (void) __pam_display_msg(pamh, PAM_ERROR_MSG, 1, 304 messages, NULL); 305 } 306 result = PAM_USER_UNKNOWN; 307 goto out; 308 } 309 310 if (server_policy && 311 strcmp(repository_name, "files") != 0 && 312 strcmp(repository_name, "nis") != 0 && 313 strcmp(repository_name, "nisplus") != 0) { 314 result = PAM_IGNORE; 315 goto out; 316 } 317 318 /* Now check the entered password */ 319 if ((crypt_passwd = crypt(passwd, rep_passwd)) == NULL) { 320 switch (errno) { 321 case ENOMEM: 322 result = PAM_BUF_ERR; 323 break; 324 case ELIBACC: 325 result = PAM_OPEN_ERR; 326 break; 327 default: 328 result = PAM_SYSTEM_ERR; 329 } 330 goto out; 331 } 332 333 if (strcmp(crypt_passwd, rep_passwd) == 0) 334 result = PAM_SUCCESS; 335 else 336 result = PAM_AUTH_ERR; 337 338 /* Clear or increment failed failed count */ 339 if (dolock && (result == PAM_SUCCESS && old_failed_count > 0)) { 340 old_failed_count = __rst_failed_count(user, repository_name); 341 if (nowarn == 0 && old_failed_count > 0) 342 display_warning(pamh, old_failed_count, homedir); 343 } else if (dolock && result == PAM_AUTH_ERR) { 344 int max_failed = get_max_failed(user); 345 if (max_failed != 0) { 346 if (__incr_failed_count(user, repository_name, 347 max_failed) == PWU_ACCOUNT_LOCKED) 348 result = PAM_MAXTRIES; 349 } 350 } 351 out: 352 if (rep_passwd) 353 free(rep_passwd); 354 if (repository_name) 355 free(repository_name); 356 if (homedir) 357 free(homedir); 358 return (result); 359 } 360 361 /*ARGSUSED*/ 362 int 363 pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv) 364 { 365 return (PAM_IGNORE); 366 } 367