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 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <kadm5/admin.h> 29 #include <krb5.h> 30 31 #include <security/pam_appl.h> 32 #include <security/pam_modules.h> 33 #include <security/pam_impl.h> 34 #include <syslog.h> 35 #include <string.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <sys/types.h> 39 #include <pwd.h> 40 #include <libintl.h> 41 #include <netdb.h> 42 #include "utils.h" 43 #include "krb5_repository.h" 44 45 extern int attempt_krb5_auth(krb5_module_data_t *, char *, char **, 46 boolean_t); 47 extern int krb5_verifypw(char *, char *, int); 48 49 static void display_msg(pam_handle_t *, int, char *); 50 static void display_msgs(pam_handle_t *, int, int, 51 char msgs[][PAM_MAX_MSG_SIZE]); 52 static int krb5_changepw(pam_handle_t *, char *, char *, char *, int); 53 54 /* 55 * set_ccname() 56 * 57 * set KRB5CCNAME shell var 58 */ 59 static void 60 set_ccname( 61 pam_handle_t *pamh, 62 krb5_module_data_t *kmd, 63 int login_result, 64 int debug) 65 { 66 int result; 67 68 if (debug) 69 __pam_log(LOG_AUTH | LOG_DEBUG, 70 "PAM-KRB5 (password): password: finalize" 71 " ccname env, login_result =%d, env ='%s'", 72 login_result, kmd->env ? kmd->env : "<null>"); 73 74 if (kmd->env) { 75 76 if (login_result == PAM_SUCCESS) { 77 /* 78 * Put ccname into the pamh so that login 79 * apps can pick this up when they run 80 * pam_getenvlist(). 81 */ 82 if ((result = pam_putenv(pamh, kmd->env)) 83 != PAM_SUCCESS) { 84 /* should not happen but... */ 85 __pam_log(LOG_AUTH | LOG_ERR, 86 "PAM-KRB5 (password):" 87 " pam_putenv failed: result: %d", 88 result); 89 goto cleanupccname; 90 } 91 } else { 92 cleanupccname: 93 /* for lack of a Solaris unputenv() */ 94 krb5_unsetenv(KRB5_ENV_CCNAME); 95 free(kmd->env); 96 kmd->env = NULL; 97 } 98 } 99 } 100 101 /* 102 * get_set_creds() 103 * 104 * do a krb5 login to get and set krb5 creds (needed after a pw change 105 * on pw expire on login) 106 */ 107 static void 108 get_set_creds( 109 pam_handle_t *pamh, 110 krb5_module_data_t *kmd, 111 char *user, 112 char *newpass, 113 int debug) 114 { 115 int login_result; 116 117 if (!kmd || kmd->age_status != PAM_NEW_AUTHTOK_REQD) 118 return; 119 120 /* 121 * if pw has expired, get/set krb5 creds ala auth mod 122 * 123 * pwchange verified user sufficiently, so don't request strict 124 * tgt verification (will cause rcache perm issues possibly anyways) 125 */ 126 login_result = attempt_krb5_auth(kmd, user, &newpass, 0); 127 if (debug) 128 __pam_log(LOG_AUTH | LOG_DEBUG, 129 "PAM-KRB5 (password): get_set_creds: login_result= %d", 130 login_result); 131 /* 132 * the krb5 login should not fail, but if so, 133 * warn the user they have to kinit(1) 134 */ 135 if (login_result != PAM_SUCCESS) { 136 display_msg(pamh, PAM_TEXT_INFO, 137 dgettext(TEXT_DOMAIN, 138 "Warning: " 139 "Could not cache Kerberos" 140 " credentials, please run " 141 "kinit(1) or re-login\n")); 142 } 143 set_ccname(pamh, kmd, login_result, debug); 144 } 145 /* 146 * This is the PAM Kerberos Password Change module 147 * 148 */ 149 150 int 151 pam_sm_chauthtok( 152 pam_handle_t *pamh, 153 int flags, 154 int argc, 155 const char **argv) 156 { 157 158 char *user; 159 int err, result = PAM_AUTHTOK_ERR; 160 char *newpass = NULL; 161 char *oldpass = NULL; 162 int i; 163 int debug = 0; 164 uid_t pw_uid; 165 krb5_module_data_t *kmd = NULL; 166 pam_repository_t *rep_data = NULL; 167 168 for (i = 0; i < argc; i++) { 169 if (strcmp(argv[i], "debug") == 0) 170 debug = 1; 171 else 172 __pam_log(LOG_AUTH | LOG_ERR, 173 "PAM-KRB5 (password): illegal option %s", 174 argv[i]); 175 } 176 177 if (debug) 178 __pam_log(LOG_AUTH | LOG_DEBUG, 179 "PAM-KRB5 (password): start: flags = %x", 180 flags); 181 182 (void) pam_get_item(pamh, PAM_REPOSITORY, (void **)&rep_data); 183 184 if (rep_data != NULL) { 185 if (strcmp(rep_data->type, KRB5_REPOSITORY_NAME) != 0) { 186 if (debug) 187 __pam_log(LOG_AUTH | LOG_DEBUG, 188 "PAM-KRB5 (auth): wrong" 189 "repository found (%s), returning " 190 "PAM_IGNORE", rep_data->type); 191 return (PAM_IGNORE); 192 } 193 } 194 195 if (flags & PAM_PRELIM_CHECK) { 196 /* Nothing to do here */ 197 if (debug) 198 __pam_log(LOG_AUTH | LOG_DEBUG, 199 "PAM-KRB5 (password): prelim check"); 200 return (PAM_IGNORE); 201 } 202 203 /* make sure PAM framework is telling us to update passwords */ 204 if (!(flags & PAM_UPDATE_AUTHTOK)) { 205 __pam_log(LOG_AUTH | LOG_ERR, 206 "PAM-KRB5 (password): bad flags: %d", 207 flags); 208 return (PAM_SYSTEM_ERR); 209 } 210 211 212 if ((err = pam_get_data(pamh, KRB5_DATA, (const void **)&kmd)) 213 != PAM_SUCCESS) { 214 if (debug) 215 __pam_log(LOG_AUTH | LOG_DEBUG, 216 "PAM-KRB5 (password): get mod data failed %d", 217 err); 218 kmd = NULL; 219 } 220 221 if (flags & PAM_CHANGE_EXPIRED_AUTHTOK) { 222 /* let's make sure we know the krb5 pw has expired */ 223 224 if (debug) 225 __pam_log(LOG_AUTH | LOG_DEBUG, 226 "PAM-KRB5 (password): kmd age status %d", 227 kmd ? kmd->age_status : -99); 228 229 if (!kmd || kmd->age_status != PAM_NEW_AUTHTOK_REQD) 230 return (PAM_IGNORE); 231 } 232 233 (void) pam_get_item(pamh, PAM_USER, (void **)&user); 234 235 if (user == NULL || *user == '\0') { 236 __pam_log(LOG_AUTH | LOG_ERR, 237 "PAM-KRB5 (password): username is empty"); 238 return (PAM_USER_UNKNOWN); 239 } 240 241 if (!get_pw_uid(user, &pw_uid)) { 242 __pam_log(LOG_AUTH | LOG_ERR, 243 "PAM-KRB5 (password): can't get uid for %s", user); 244 return (PAM_USER_UNKNOWN); 245 } 246 247 /* 248 * if root key exists in the keytab, it's a random key so no 249 * need to prompt for pw and we just return IGNORE 250 */ 251 if ((strcmp(user, ROOT_UNAME) == 0) && 252 key_in_keytab(user, debug)) { 253 if (debug) 254 __pam_log(LOG_AUTH | LOG_DEBUG, 255 "PAM-KRB5 (password): " 256 "key for '%s' in keytab, returning IGNORE", user); 257 result = PAM_IGNORE; 258 goto out; 259 } 260 261 (void) pam_get_item(pamh, PAM_AUTHTOK, (void **)&newpass); 262 263 if (newpass == NULL) 264 return (PAM_SYSTEM_ERR); 265 266 (void) pam_get_item(pamh, PAM_OLDAUTHTOK, (void **)&oldpass); 267 268 if (oldpass == NULL) 269 return (PAM_SYSTEM_ERR); 270 271 result = krb5_verifypw(user, oldpass, debug); 272 if (debug) 273 __pam_log(LOG_AUTH | LOG_DEBUG, 274 "PAM-KRB5 (password): verifypw %d", result); 275 276 /* 277 * If it's a bad password or general failure, we are done. 278 */ 279 if (result != 0) { 280 if (result == 2) 281 display_msg(pamh, PAM_ERROR_MSG, dgettext(TEXT_DOMAIN, 282 "Old Kerberos password incorrect\n")); 283 return (PAM_AUTHTOK_ERR); 284 } 285 286 result = krb5_changepw(pamh, user, oldpass, newpass, debug); 287 if (result == PAM_SUCCESS) { 288 display_msg(pamh, PAM_TEXT_INFO, dgettext(TEXT_DOMAIN, 289 "Kerberos password successfully changed\n")); 290 291 get_set_creds(pamh, kmd, user, newpass, debug); 292 } 293 294 out: 295 if (debug) 296 __pam_log(LOG_AUTH | LOG_DEBUG, 297 "PAM-KRB5 (password): out: returns %d", 298 result); 299 300 return (result); 301 } 302 303 int 304 krb5_verifypw( 305 char *princ_str, 306 char *old_password, 307 int debug) 308 { 309 kadm5_ret_t code; 310 krb5_principal princ = 0; 311 char admin_realm[1024]; 312 char kprinc[2*MAXHOSTNAMELEN]; 313 char *cpw_service; 314 void *server_handle; 315 krb5_context context; 316 kadm5_config_params params; 317 318 (void) memset((char *)¶ms, 0, sizeof (params)); 319 320 if (code = krb5_init_context(&context)) { 321 return (6); 322 } 323 324 if ((code = get_kmd_kuser(context, (const char *)princ_str, kprinc, 325 2*MAXHOSTNAMELEN)) != 0) { 326 return (code); 327 } 328 329 /* Need to get a krb5_principal struct */ 330 331 code = krb5_parse_name(context, kprinc, &princ); 332 333 if (code != 0) 334 return (6); 335 336 if (strlen(old_password) == 0) { 337 krb5_free_principal(context, princ); 338 return (5); 339 } 340 341 (void) strlcpy(admin_realm, 342 krb5_princ_realm(context, princ)->data, 343 sizeof (admin_realm)); 344 345 params.mask |= KADM5_CONFIG_REALM; 346 params.realm = admin_realm; 347 348 349 if (kadm5_get_cpw_host_srv_name(context, admin_realm, &cpw_service)) { 350 __pam_log(LOG_AUTH | LOG_ERR, 351 "PAM-KRB5 (password): unable to get host based " 352 "service name for realm %s\n", 353 admin_realm); 354 krb5_free_principal(context, princ); 355 return (3); 356 } 357 358 code = kadm5_init_with_password(kprinc, old_password, cpw_service, 359 ¶ms, KADM5_STRUCT_VERSION, 360 KADM5_API_VERSION_2, NULL, 361 &server_handle); 362 if (code != 0) { 363 if (debug) 364 __pam_log(LOG_AUTH | LOG_DEBUG, 365 "PAM-KRB5: krb5_verifypw: init_with_pw" 366 " failed: (%s)", error_message(code)); 367 krb5_free_principal(context, princ); 368 return ((code == KADM5_BAD_PASSWORD) ? 2 : 3); 369 } 370 371 krb5_free_principal(context, princ); 372 373 (void) kadm5_destroy(server_handle); 374 375 return (0); 376 } 377 378 /* 379 * Function: krb5_changepw 380 * 381 * Purpose: Initialize and call lower level routines to change a password 382 * 383 * Arguments: 384 * 385 * princ_str principal name to use, optional 386 * old_password old password 387 * new_password new password 388 * 389 * Returns: 390 * exit status of PAM_SUCCESS for success 391 * else returns PAM failure 392 * 393 * Requires: 394 * Passwords cannot be more than 255 characters long. 395 * 396 * Modifies: 397 * 398 * Changes the principal's password. 399 * 400 */ 401 static int 402 krb5_changepw( 403 pam_handle_t *pamh, 404 char *princ_str, 405 char *old_password, 406 char *new_password, 407 int debug) 408 { 409 kadm5_ret_t code; 410 krb5_principal princ = 0; 411 char msg_ret[1024], admin_realm[1024]; 412 char kprinc[2*MAXHOSTNAMELEN]; 413 char *cpw_service; 414 void *server_handle; 415 krb5_context context; 416 kadm5_config_params params; 417 418 (void) memset((char *)¶ms, 0, sizeof (params)); 419 420 if (krb5_init_context(&context) != 0) 421 return (PAM_SYSTEM_ERR); 422 423 if ((code = get_kmd_kuser(context, (const char *)princ_str, kprinc, 424 2*MAXHOSTNAMELEN)) != 0) { 425 return (code); 426 } 427 428 /* Need to get a krb5_principal struct */ 429 430 code = krb5_parse_name(context, kprinc, &princ); 431 if (code != 0) 432 return (PAM_SYSTEM_ERR); 433 434 if (strlen(old_password) == 0) { 435 krb5_free_principal(context, princ); 436 return (PAM_AUTHTOK_ERR); 437 } 438 439 (void) snprintf(admin_realm, sizeof (admin_realm), "%s", 440 krb5_princ_realm(context, princ)->data); 441 params.mask |= KADM5_CONFIG_REALM; 442 params.realm = admin_realm; 443 444 445 if (kadm5_get_cpw_host_srv_name(context, admin_realm, &cpw_service)) { 446 __pam_log(LOG_AUTH | LOG_ERR, 447 "PAM-KRB5 (password):unable to get host based " 448 "service name for realm %s\n", 449 admin_realm); 450 return (PAM_SYSTEM_ERR); 451 } 452 453 code = kadm5_init_with_password(kprinc, old_password, cpw_service, 454 ¶ms, KADM5_STRUCT_VERSION, 455 KADM5_API_VERSION_2, NULL, 456 &server_handle); 457 free(cpw_service); 458 if (code != 0) { 459 if (debug) 460 __pam_log(LOG_AUTH | LOG_DEBUG, 461 "PAM-KRB5 (password): changepw: " 462 "init_with_pw failed: (%s)", error_message(code)); 463 krb5_free_principal(context, princ); 464 return ((code == KADM5_BAD_PASSWORD) ? 465 PAM_AUTHTOK_ERR : PAM_SYSTEM_ERR); 466 } 467 468 code = kadm5_chpass_principal_util(server_handle, princ, 469 new_password, 470 NULL /* don't need pw back */, 471 msg_ret, 472 sizeof (msg_ret)); 473 474 if (code) { 475 char msgs[2][PAM_MAX_MSG_SIZE]; 476 477 (void) snprintf(msgs[0], PAM_MAX_MSG_SIZE, "%s", 478 dgettext(TEXT_DOMAIN, 479 "Kerberos password not changed: ")); 480 (void) snprintf(msgs[1], PAM_MAX_MSG_SIZE, "%s", msg_ret); 481 482 display_msgs(pamh, PAM_ERROR_MSG, 2, msgs); 483 } 484 485 krb5_free_principal(context, princ); 486 487 (void) kadm5_destroy(server_handle); 488 489 if (debug) 490 __pam_log(LOG_AUTH | LOG_DEBUG, 491 "PAM-KRB5 (password): changepw: end %d", code); 492 493 if (code != 0) 494 return (PAM_AUTHTOK_ERR); 495 496 return (PAM_SUCCESS); 497 } 498 499 static void 500 display_msgs(pam_handle_t *pamh, 501 int msg_style, int nmsg, char msgs[][PAM_MAX_MSG_SIZE]) 502 { 503 (void) __pam_display_msg(pamh, msg_style, nmsg, msgs, NULL); 504 } 505 506 507 static void 508 display_msg(pam_handle_t *pamh, int msg_style, char *msg) 509 { 510 char pam_msg[1][PAM_MAX_MSG_SIZE]; 511 512 (void) snprintf(pam_msg[0], PAM_MAX_MSG_SIZE, "%s", msg); 513 display_msgs(pamh, msg_style, 1, pam_msg); 514 } 515