139384277SMark Murray /*- 2e0bc7412SJacques Vidrine * This pam_krb5 module contains code that is: 3e0bc7412SJacques Vidrine * Copyright (c) Derrick J. Brashear, 1996. All rights reserved. 4e0bc7412SJacques Vidrine * Copyright (c) Frank Cusack, 1999-2001. All rights reserved. 5e0bc7412SJacques Vidrine * Copyright (c) Jacques A. Vidrine, 2000-2001. All rights reserved. 6e0bc7412SJacques Vidrine * Copyright (c) Nicolas Williams, 2001. All rights reserved. 7e0bc7412SJacques Vidrine * Copyright (c) Perot Systems Corporation, 2001. All rights reserved. 8e0bc7412SJacques Vidrine * Copyright (c) Mark R V Murray, 2001. All rights reserved. 916417879SRobert Watson * Copyright (c) Networks Associates Technology, Inc., 2002-2005. 10111ccd25SDag-Erling Smørgrav * All rights reserved. 11111ccd25SDag-Erling Smørgrav * 12111ccd25SDag-Erling Smørgrav * Portions of this software were developed for the FreeBSD Project by 13111ccd25SDag-Erling Smørgrav * ThinkSec AS and NAI Labs, the Security Research Division of Network 14111ccd25SDag-Erling Smørgrav * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 15111ccd25SDag-Erling Smørgrav * ("CBOSS"), as part of the DARPA CHATS research program. 1639384277SMark Murray * 1739384277SMark Murray * Redistribution and use in source and binary forms, with or without 1839384277SMark Murray * modification, are permitted provided that the following conditions 1939384277SMark Murray * are met: 2039384277SMark Murray * 1. Redistributions of source code must retain the above copyright 21e0bc7412SJacques Vidrine * notices, and the entire permission notice in its entirety, 2239384277SMark Murray * including the disclaimer of warranties. 2339384277SMark Murray * 2. Redistributions in binary form must reproduce the above copyright 2439384277SMark Murray * notice, this list of conditions and the following disclaimer in the 2539384277SMark Murray * documentation and/or other materials provided with the distribution. 2639384277SMark Murray * 3. The name of the author may not be used to endorse or promote 2739384277SMark Murray * products derived from this software without specific prior 2839384277SMark Murray * written permission. 2939384277SMark Murray * 3039384277SMark Murray * ALTERNATIVELY, this product may be distributed under the terms of 3139384277SMark Murray * the GNU Public License, in which case the provisions of the GPL are 3239384277SMark Murray * required INSTEAD OF the above restrictions. (This clause is 3339384277SMark Murray * necessary due to a potential bad interaction between the GPL and 3439384277SMark Murray * the restrictions contained in a BSD-style copyright.) 3539384277SMark Murray * 3639384277SMark Murray * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 3739384277SMark Murray * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 3839384277SMark Murray * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 3939384277SMark Murray * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 4039384277SMark Murray * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 4139384277SMark Murray * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 4239384277SMark Murray * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 4339384277SMark Murray * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 4439384277SMark Murray * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 4539384277SMark Murray * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 4639384277SMark Murray * OF THE POSSIBILITY OF SUCH DAMAGE. 4739384277SMark Murray * 4839384277SMark Murray */ 4939384277SMark Murray 50ceaf33f5SMatthew Dillon #include <sys/cdefs.h> 51ceaf33f5SMatthew Dillon __FBSDID("$FreeBSD$"); 52ceaf33f5SMatthew Dillon 5339384277SMark Murray #include <sys/types.h> 5439384277SMark Murray #include <sys/stat.h> 5539384277SMark Murray #include <errno.h> 5639384277SMark Murray #include <limits.h> 5739384277SMark Murray #include <pwd.h> 5839384277SMark Murray #include <stdio.h> 5939384277SMark Murray #include <stdlib.h> 60111ccd25SDag-Erling Smørgrav #include <string.h> 6139384277SMark Murray #include <syslog.h> 6239384277SMark Murray #include <unistd.h> 6339384277SMark Murray 6439384277SMark Murray #include <krb5.h> 6539384277SMark Murray #include <com_err.h> 6639384277SMark Murray 6739384277SMark Murray #define PAM_SM_AUTH 6839384277SMark Murray #define PAM_SM_ACCOUNT 6939384277SMark Murray #define PAM_SM_PASSWORD 7039384277SMark Murray 7139384277SMark Murray #include <security/pam_appl.h> 7239384277SMark Murray #include <security/pam_modules.h> 738c66575dSDag-Erling Smørgrav #include <security/pam_mod_misc.h> 74545aa471SDag-Erling Smørgrav #include <security/openpam.h> 7539384277SMark Murray 7639384277SMark Murray #define COMPAT_HEIMDAL 7739384277SMark Murray /* #define COMPAT_MIT */ 7839384277SMark Murray 7939384277SMark Murray static int verify_krb_v5_tgt(krb5_context, krb5_ccache, char *, int); 8039384277SMark Murray static void cleanup_cache(pam_handle_t *, void *, int); 8139384277SMark Murray static const char *compat_princ_component(krb5_context, krb5_principal, int); 8239384277SMark Murray static void compat_free_data_contents(krb5_context, krb5_data *); 8339384277SMark Murray 8439384277SMark Murray #define USER_PROMPT "Username: " 8539384277SMark Murray #define PASSWORD_PROMPT "Password:" 8639384277SMark Murray #define NEW_PASSWORD_PROMPT "New Password:" 8739384277SMark Murray 88545aa471SDag-Erling Smørgrav #define PAM_OPT_CCACHE "ccache" 8916417879SRobert Watson #define PAM_OPT_DEBUG "debug" 90545aa471SDag-Erling Smørgrav #define PAM_OPT_FORWARDABLE "forwardable" 91545aa471SDag-Erling Smørgrav #define PAM_OPT_NO_CCACHE "no_ccache" 92551e75c7SMartin Matuska #define PAM_OPT_NO_USER_CHECK "no_user_check" 93545aa471SDag-Erling Smørgrav #define PAM_OPT_REUSE_CCACHE "reuse_ccache" 9439384277SMark Murray 9539384277SMark Murray /* 9639384277SMark Murray * authentication management 9739384277SMark Murray */ 9839384277SMark Murray PAM_EXTERN int 9924fe7ba0SDag-Erling Smørgrav pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 100545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 10139384277SMark Murray { 10239384277SMark Murray krb5_error_code krbret; 10339384277SMark Murray krb5_context pam_context; 10439384277SMark Murray krb5_creds creds; 10539384277SMark Murray krb5_principal princ; 1067c2274dcSJacques Vidrine krb5_ccache ccache; 10739384277SMark Murray krb5_get_init_creds_opt opts; 10839384277SMark Murray struct passwd *pwd; 10939384277SMark Murray int retval; 11064dbe1a7SDag-Erling Smørgrav const void *ccache_data; 1114911b12cSDag-Erling Smørgrav const char *user, *pass; 112af9b4074SDag-Erling Smørgrav const void *sourceuser, *service; 1137c2274dcSJacques Vidrine char *principal, *princ_name, *ccache_name, luser[32], *srvdup; 11439384277SMark Murray 11539384277SMark Murray retval = pam_get_user(pamh, &user, USER_PROMPT); 11639384277SMark Murray if (retval != PAM_SUCCESS) 11724fe7ba0SDag-Erling Smørgrav return (retval); 11839384277SMark Murray 11939384277SMark Murray PAM_LOG("Got user: %s", user); 12039384277SMark Murray 1214911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_RUSER, &sourceuser); 12239384277SMark Murray if (retval != PAM_SUCCESS) 12324fe7ba0SDag-Erling Smørgrav return (retval); 12439384277SMark Murray 1254911b12cSDag-Erling Smørgrav PAM_LOG("Got ruser: %s", (const char *)sourceuser); 12639384277SMark Murray 12739384277SMark Murray service = NULL; 1284911b12cSDag-Erling Smørgrav pam_get_item(pamh, PAM_SERVICE, &service); 12939384277SMark Murray if (service == NULL) 13039384277SMark Murray service = "unknown"; 13139384277SMark Murray 1324911b12cSDag-Erling Smørgrav PAM_LOG("Got service: %s", (const char *)service); 13339384277SMark Murray 13439384277SMark Murray krbret = krb5_init_context(&pam_context); 13539384277SMark Murray if (krbret != 0) { 13639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 13724fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 13839384277SMark Murray } 13939384277SMark Murray 14039384277SMark Murray PAM_LOG("Context initialised"); 14139384277SMark Murray 14239384277SMark Murray krb5_get_init_creds_opt_init(&opts); 14339384277SMark Murray 144545aa471SDag-Erling Smørgrav if (openpam_get_option(pamh, PAM_OPT_FORWARDABLE)) 14539384277SMark Murray krb5_get_init_creds_opt_set_forwardable(&opts, 1); 14639384277SMark Murray 14739384277SMark Murray PAM_LOG("Credentials initialised"); 14839384277SMark Murray 14939384277SMark Murray krbret = krb5_cc_register(pam_context, &krb5_mcc_ops, FALSE); 15039384277SMark Murray if (krbret != 0 && krbret != KRB5_CC_TYPE_EXISTS) { 15139384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 15239384277SMark Murray retval = PAM_SERVICE_ERR; 15339384277SMark Murray goto cleanup3; 15439384277SMark Murray } 15539384277SMark Murray 15639384277SMark Murray PAM_LOG("Done krb5_cc_register()"); 15739384277SMark Murray 15839384277SMark Murray /* Get principal name */ 159545aa471SDag-Erling Smørgrav if (openpam_get_option(pamh, PAM_OPT_AUTH_AS_SELF)) 1604911b12cSDag-Erling Smørgrav asprintf(&principal, "%s/%s", (const char *)sourceuser, user); 16139384277SMark Murray else 16239384277SMark Murray principal = strdup(user); 16339384277SMark Murray 16439384277SMark Murray PAM_LOG("Created principal: %s", principal); 16539384277SMark Murray 16639384277SMark Murray krbret = krb5_parse_name(pam_context, principal, &princ); 16739384277SMark Murray free(principal); 16839384277SMark Murray if (krbret != 0) { 16988c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 17088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 17139384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 17239384277SMark Murray retval = PAM_SERVICE_ERR; 17339384277SMark Murray goto cleanup3; 17439384277SMark Murray } 17539384277SMark Murray 17639384277SMark Murray PAM_LOG("Done krb5_parse_name()"); 17739384277SMark Murray 17839384277SMark Murray /* Now convert the principal name into something human readable */ 17939384277SMark Murray princ_name = NULL; 18039384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 18139384277SMark Murray if (krbret != 0) { 18288c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 18388c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 18439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 18539384277SMark Murray retval = PAM_SERVICE_ERR; 18639384277SMark Murray goto cleanup2; 18739384277SMark Murray } 18839384277SMark Murray 18939384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 19039384277SMark Murray 19139384277SMark Murray /* Get password */ 192111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 19339384277SMark Murray if (retval != PAM_SUCCESS) 19439384277SMark Murray goto cleanup2; 19539384277SMark Murray 19639384277SMark Murray PAM_LOG("Got password"); 19739384277SMark Murray 198551e75c7SMartin Matuska if (openpam_get_option(pamh, PAM_OPT_NO_USER_CHECK)) 199551e75c7SMartin Matuska PAM_LOG("Skipping local user check"); 200551e75c7SMartin Matuska else { 201551e75c7SMartin Matuska 20239384277SMark Murray /* Verify the local user exists (AFTER getting the password) */ 20339384277SMark Murray if (strchr(user, '@')) { 20439384277SMark Murray /* get a local account name for this principal */ 20539384277SMark Murray krbret = krb5_aname_to_localname(pam_context, princ, 20639384277SMark Murray sizeof(luser), luser); 20739384277SMark Murray if (krbret != 0) { 20839384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 20939384277SMark Murray PAM_LOG("Error krb5_aname_to_localname(): %s", 21088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 21139384277SMark Murray retval = PAM_USER_UNKNOWN; 21239384277SMark Murray goto cleanup2; 21339384277SMark Murray } 21439384277SMark Murray 21539384277SMark Murray retval = pam_set_item(pamh, PAM_USER, luser); 21639384277SMark Murray if (retval != PAM_SUCCESS) 21739384277SMark Murray goto cleanup2; 21839384277SMark Murray 21939384277SMark Murray PAM_LOG("PAM_USER Redone"); 22039384277SMark Murray } 22139384277SMark Murray 22239384277SMark Murray pwd = getpwnam(user); 22339384277SMark Murray if (pwd == NULL) { 22439384277SMark Murray retval = PAM_USER_UNKNOWN; 22539384277SMark Murray goto cleanup2; 22639384277SMark Murray } 22739384277SMark Murray 22839384277SMark Murray PAM_LOG("Done getpwnam()"); 229551e75c7SMartin Matuska } 23039384277SMark Murray 23139384277SMark Murray /* Get a TGT */ 23239384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 23339384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 23439384277SMark Murray pass, NULL, pamh, 0, NULL, &opts); 23539384277SMark Murray if (krbret != 0) { 23639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 23739384277SMark Murray PAM_LOG("Error krb5_get_init_creds_password(): %s", 23888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 23939384277SMark Murray retval = PAM_AUTH_ERR; 24039384277SMark Murray goto cleanup2; 24139384277SMark Murray } 24239384277SMark Murray 24339384277SMark Murray PAM_LOG("Got TGT"); 24439384277SMark Murray 2457c2274dcSJacques Vidrine /* Generate a temporary cache */ 2467c2274dcSJacques Vidrine krbret = krb5_cc_gen_new(pam_context, &krb5_mcc_ops, &ccache); 24739384277SMark Murray if (krbret != 0) { 24839384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 2497c2274dcSJacques Vidrine PAM_LOG("Error krb5_cc_gen_new(): %s", 25088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 25139384277SMark Murray retval = PAM_SERVICE_ERR; 25239384277SMark Murray goto cleanup; 25339384277SMark Murray } 25439384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache, princ); 25539384277SMark Murray if (krbret != 0) { 25639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 25788c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 25888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 25939384277SMark Murray retval = PAM_SERVICE_ERR; 26039384277SMark Murray goto cleanup; 26139384277SMark Murray } 26239384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache, &creds); 26339384277SMark Murray if (krbret != 0) { 26439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 26588c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_store_cred(): %s", 26688c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 26739384277SMark Murray krb5_cc_destroy(pam_context, ccache); 26839384277SMark Murray retval = PAM_SERVICE_ERR; 26939384277SMark Murray goto cleanup; 27039384277SMark Murray } 27139384277SMark Murray 27239384277SMark Murray PAM_LOG("Credentials stashed"); 27339384277SMark Murray 27439384277SMark Murray /* Verify them */ 275111ccd25SDag-Erling Smørgrav if ((srvdup = strdup(service)) == NULL) { 276111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 277111ccd25SDag-Erling Smørgrav goto cleanup; 278111ccd25SDag-Erling Smørgrav } 279111ccd25SDag-Erling Smørgrav krbret = verify_krb_v5_tgt(pam_context, ccache, srvdup, 28016417879SRobert Watson openpam_get_option(pamh, PAM_OPT_DEBUG) ? 1 : 0); 281111ccd25SDag-Erling Smørgrav free(srvdup); 282111ccd25SDag-Erling Smørgrav if (krbret == -1) { 28339384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 28439384277SMark Murray krb5_cc_destroy(pam_context, ccache); 28539384277SMark Murray retval = PAM_AUTH_ERR; 28639384277SMark Murray goto cleanup; 28739384277SMark Murray } 28839384277SMark Murray 28939384277SMark Murray PAM_LOG("Credentials stash verified"); 29039384277SMark Murray 291af9b4074SDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &ccache_data); 29239384277SMark Murray if (retval == PAM_SUCCESS) { 29339384277SMark Murray krb5_cc_destroy(pam_context, ccache); 29439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 29539384277SMark Murray retval = PAM_AUTH_ERR; 29639384277SMark Murray goto cleanup; 29739384277SMark Murray } 29839384277SMark Murray 29939384277SMark Murray PAM_LOG("Credentials stash not pre-existing"); 30039384277SMark Murray 3017c2274dcSJacques Vidrine asprintf(&ccache_name, "%s:%s", krb5_cc_get_type(pam_context, 3027c2274dcSJacques Vidrine ccache), krb5_cc_get_name(pam_context, ccache)); 3037c2274dcSJacques Vidrine if (ccache_name == NULL) { 3047c2274dcSJacques Vidrine PAM_VERBOSE_ERROR("Kerberos 5 error"); 3057c2274dcSJacques Vidrine retval = PAM_BUF_ERR; 3067c2274dcSJacques Vidrine goto cleanup; 3077c2274dcSJacques Vidrine } 3087c2274dcSJacques Vidrine retval = pam_set_data(pamh, "ccache", ccache_name, cleanup_cache); 30939384277SMark Murray if (retval != 0) { 31039384277SMark Murray krb5_cc_destroy(pam_context, ccache); 31139384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 31239384277SMark Murray retval = PAM_SERVICE_ERR; 31339384277SMark Murray goto cleanup; 31439384277SMark Murray } 31539384277SMark Murray 31639384277SMark Murray PAM_LOG("Credentials stash saved"); 31739384277SMark Murray 31839384277SMark Murray cleanup: 31939384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 32039384277SMark Murray PAM_LOG("Done cleanup"); 32139384277SMark Murray cleanup2: 32239384277SMark Murray krb5_free_principal(pam_context, princ); 32339384277SMark Murray PAM_LOG("Done cleanup2"); 32439384277SMark Murray cleanup3: 32539384277SMark Murray if (princ_name) 32639384277SMark Murray free(princ_name); 32739384277SMark Murray 32839384277SMark Murray krb5_free_context(pam_context); 32939384277SMark Murray 33039384277SMark Murray PAM_LOG("Done cleanup3"); 33139384277SMark Murray 33239384277SMark Murray if (retval != PAM_SUCCESS) 33339384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 refuses you"); 33439384277SMark Murray 33524fe7ba0SDag-Erling Smørgrav return (retval); 33639384277SMark Murray } 33739384277SMark Murray 33839384277SMark Murray PAM_EXTERN int 33924fe7ba0SDag-Erling Smørgrav pam_sm_setcred(pam_handle_t *pamh, int flags, 340545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 34139384277SMark Murray { 3422672e717SKen Smith #ifdef _FREEFALL_CONFIG 3432672e717SKen Smith return (PAM_SUCCESS); 3442672e717SKen Smith #else 34539384277SMark Murray 34639384277SMark Murray krb5_error_code krbret; 34739384277SMark Murray krb5_context pam_context; 34839384277SMark Murray krb5_principal princ; 34939384277SMark Murray krb5_creds creds; 35039384277SMark Murray krb5_ccache ccache_temp, ccache_perm; 35139384277SMark Murray krb5_cc_cursor cursor; 35239384277SMark Murray struct passwd *pwd = NULL; 35339384277SMark Murray int retval; 3544911b12cSDag-Erling Smørgrav const char *cache_name, *q; 355af9b4074SDag-Erling Smørgrav const void *user; 35664dbe1a7SDag-Erling Smørgrav const void *cache_data; 357545aa471SDag-Erling Smørgrav char *cache_name_buf = NULL, *p; 35839384277SMark Murray 35939384277SMark Murray uid_t euid; 36039384277SMark Murray gid_t egid; 36139384277SMark Murray 36239384277SMark Murray if (flags & PAM_DELETE_CRED) 36324fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 36439384277SMark Murray 36539384277SMark Murray if (flags & PAM_REFRESH_CRED) 36624fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 36739384277SMark Murray 36839384277SMark Murray if (flags & PAM_REINITIALIZE_CRED) 36924fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 37039384277SMark Murray 37139384277SMark Murray if (!(flags & PAM_ESTABLISH_CRED)) 37224fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 37339384277SMark Murray 374ed41980cSRobert Watson /* If a persistent cache isn't desired, stop now. */ 375551e75c7SMartin Matuska if (openpam_get_option(pamh, PAM_OPT_NO_CCACHE) || 376551e75c7SMartin Matuska openpam_get_option(pamh, PAM_OPT_NO_USER_CHECK)) 377ed41980cSRobert Watson return (PAM_SUCCESS); 378ed41980cSRobert Watson 37939384277SMark Murray PAM_LOG("Establishing credentials"); 38039384277SMark Murray 38139384277SMark Murray /* Get username */ 3824911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 38339384277SMark Murray if (retval != PAM_SUCCESS) 38424fe7ba0SDag-Erling Smørgrav return (retval); 38539384277SMark Murray 3864911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 38739384277SMark Murray 38839384277SMark Murray krbret = krb5_init_context(&pam_context); 38939384277SMark Murray if (krbret != 0) { 39088c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 39124fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 39239384277SMark Murray } 39339384277SMark Murray 39439384277SMark Murray PAM_LOG("Context initialised"); 39539384277SMark Murray 39639384277SMark Murray euid = geteuid(); /* Usually 0 */ 39739384277SMark Murray egid = getegid(); 39839384277SMark Murray 39939384277SMark Murray PAM_LOG("Got euid, egid: %d %d", euid, egid); 40039384277SMark Murray 4017c2274dcSJacques Vidrine /* Retrieve the temporary cache */ 4024911b12cSDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &cache_data); 4038f857e88SJacques Vidrine if (retval != PAM_SUCCESS) { 4048f857e88SJacques Vidrine retval = PAM_CRED_UNAVAIL; 40539384277SMark Murray goto cleanup3; 4068f857e88SJacques Vidrine } 4074911b12cSDag-Erling Smørgrav krbret = krb5_cc_resolve(pam_context, cache_data, &ccache_temp); 4087c2274dcSJacques Vidrine if (krbret != 0) { 4094911b12cSDag-Erling Smørgrav PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", (const char *)cache_data, 4107c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 4118f857e88SJacques Vidrine retval = PAM_SERVICE_ERR; 4127c2274dcSJacques Vidrine goto cleanup3; 4137c2274dcSJacques Vidrine } 41439384277SMark Murray 41539384277SMark Murray /* Get the uid. This should exist. */ 41639384277SMark Murray pwd = getpwnam(user); 41739384277SMark Murray if (pwd == NULL) { 41839384277SMark Murray retval = PAM_USER_UNKNOWN; 41939384277SMark Murray goto cleanup3; 42039384277SMark Murray } 42139384277SMark Murray 42239384277SMark Murray PAM_LOG("Done getpwnam()"); 42339384277SMark Murray 42439384277SMark Murray /* Avoid following a symlink as root */ 42539384277SMark Murray if (setegid(pwd->pw_gid)) { 42639384277SMark Murray retval = PAM_SERVICE_ERR; 42739384277SMark Murray goto cleanup3; 42839384277SMark Murray } 42939384277SMark Murray if (seteuid(pwd->pw_uid)) { 43039384277SMark Murray retval = PAM_SERVICE_ERR; 43139384277SMark Murray goto cleanup3; 43239384277SMark Murray } 43339384277SMark Murray 43439384277SMark Murray PAM_LOG("Done setegid() & seteuid()"); 43539384277SMark Murray 43639384277SMark Murray /* Get the cache name */ 437545aa471SDag-Erling Smørgrav cache_name = openpam_get_option(pamh, PAM_OPT_CCACHE); 438545aa471SDag-Erling Smørgrav if (cache_name == NULL) { 439545aa471SDag-Erling Smørgrav asprintf(&cache_name_buf, "FILE:/tmp/krb5cc_%d", pwd->pw_uid); 440545aa471SDag-Erling Smørgrav cache_name = cache_name_buf; 441545aa471SDag-Erling Smørgrav } 44239384277SMark Murray 44339384277SMark Murray p = calloc(PATH_MAX + 16, sizeof(char)); 44439384277SMark Murray q = cache_name; 44539384277SMark Murray 44639384277SMark Murray if (p == NULL) { 44739384277SMark Murray PAM_LOG("Error malloc(): failure"); 44839384277SMark Murray retval = PAM_BUF_ERR; 44939384277SMark Murray goto cleanup3; 45039384277SMark Murray } 45139384277SMark Murray cache_name = p; 45239384277SMark Murray 45339384277SMark Murray /* convert %u and %p */ 45439384277SMark Murray while (*q) { 45539384277SMark Murray if (*q == '%') { 45639384277SMark Murray q++; 45739384277SMark Murray if (*q == 'u') { 45839384277SMark Murray sprintf(p, "%d", pwd->pw_uid); 45939384277SMark Murray p += strlen(p); 46039384277SMark Murray } 46139384277SMark Murray else if (*q == 'p') { 46239384277SMark Murray sprintf(p, "%d", getpid()); 46339384277SMark Murray p += strlen(p); 46439384277SMark Murray } 46539384277SMark Murray else { 46639384277SMark Murray /* Not a special token */ 46739384277SMark Murray *p++ = '%'; 46839384277SMark Murray q--; 46939384277SMark Murray } 47039384277SMark Murray q++; 47139384277SMark Murray } 47239384277SMark Murray else { 47339384277SMark Murray *p++ = *q++; 47439384277SMark Murray } 47539384277SMark Murray } 47639384277SMark Murray 47739384277SMark Murray PAM_LOG("Got cache_name: %s", cache_name); 47839384277SMark Murray 47939384277SMark Murray /* Initialize the new ccache */ 48039384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache_temp, &princ); 48139384277SMark Murray if (krbret != 0) { 48239384277SMark Murray PAM_LOG("Error krb5_cc_get_principal(): %s", 48388c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 48439384277SMark Murray retval = PAM_SERVICE_ERR; 48539384277SMark Murray goto cleanup3; 48639384277SMark Murray } 48739384277SMark Murray krbret = krb5_cc_resolve(pam_context, cache_name, &ccache_perm); 48839384277SMark Murray if (krbret != 0) { 48988c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_resolve(): %s", 49088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 49139384277SMark Murray retval = PAM_SERVICE_ERR; 49239384277SMark Murray goto cleanup2; 49339384277SMark Murray } 49439384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache_perm, princ); 49539384277SMark Murray if (krbret != 0) { 49688c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 49788c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 49839384277SMark Murray retval = PAM_SERVICE_ERR; 49939384277SMark Murray goto cleanup2; 50039384277SMark Murray } 50139384277SMark Murray 50239384277SMark Murray PAM_LOG("Cache initialised"); 50339384277SMark Murray 50439384277SMark Murray /* Prepare for iteration over creds */ 50539384277SMark Murray krbret = krb5_cc_start_seq_get(pam_context, ccache_temp, &cursor); 50639384277SMark Murray if (krbret != 0) { 50788c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_start_seq_get(): %s", 50888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 50939384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 51039384277SMark Murray retval = PAM_SERVICE_ERR; 51139384277SMark Murray goto cleanup2; 51239384277SMark Murray } 51339384277SMark Murray 51439384277SMark Murray PAM_LOG("Prepared for iteration"); 51539384277SMark Murray 51639384277SMark Murray /* Copy the creds (should be two of them) */ 51739384277SMark Murray while ((krbret = krb5_cc_next_cred(pam_context, ccache_temp, 51839384277SMark Murray &cursor, &creds) == 0)) { 51939384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache_perm, &creds); 52039384277SMark Murray if (krbret != 0) { 52139384277SMark Murray PAM_LOG("Error krb5_cc_store_cred(): %s", 52288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 52339384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 52439384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 52539384277SMark Murray retval = PAM_SERVICE_ERR; 52639384277SMark Murray goto cleanup2; 52739384277SMark Murray } 52839384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 52939384277SMark Murray PAM_LOG("Iteration"); 53039384277SMark Murray } 53139384277SMark Murray krb5_cc_end_seq_get(pam_context, ccache_temp, &cursor); 53239384277SMark Murray 53339384277SMark Murray PAM_LOG("Done iterating"); 53439384277SMark Murray 53539384277SMark Murray if (strstr(cache_name, "FILE:") == cache_name) { 53639384277SMark Murray if (chown(&cache_name[5], pwd->pw_uid, pwd->pw_gid) == -1) { 53739384277SMark Murray PAM_LOG("Error chown(): %s", strerror(errno)); 53839384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 53939384277SMark Murray retval = PAM_SERVICE_ERR; 54039384277SMark Murray goto cleanup2; 54139384277SMark Murray } 54239384277SMark Murray PAM_LOG("Done chown()"); 54339384277SMark Murray 54439384277SMark Murray if (chmod(&cache_name[5], (S_IRUSR | S_IWUSR)) == -1) { 54539384277SMark Murray PAM_LOG("Error chmod(): %s", strerror(errno)); 54639384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 54739384277SMark Murray retval = PAM_SERVICE_ERR; 54839384277SMark Murray goto cleanup2; 54939384277SMark Murray } 55039384277SMark Murray PAM_LOG("Done chmod()"); 55139384277SMark Murray } 55239384277SMark Murray 55339384277SMark Murray krb5_cc_close(pam_context, ccache_perm); 55439384277SMark Murray 55539384277SMark Murray PAM_LOG("Cache closed"); 55639384277SMark Murray 557545aa471SDag-Erling Smørgrav retval = pam_setenv(pamh, "KRB5CCNAME", cache_name, 1); 558545aa471SDag-Erling Smørgrav if (retval != PAM_SUCCESS) { 559545aa471SDag-Erling Smørgrav PAM_LOG("Error pam_setenv(): %s", pam_strerror(pamh, retval)); 56039384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 56139384277SMark Murray retval = PAM_SERVICE_ERR; 56239384277SMark Murray goto cleanup2; 56339384277SMark Murray } 56439384277SMark Murray 56539384277SMark Murray PAM_LOG("Environment done: KRB5CCNAME=%s", cache_name); 56639384277SMark Murray 56739384277SMark Murray cleanup2: 56839384277SMark Murray krb5_free_principal(pam_context, princ); 56939384277SMark Murray PAM_LOG("Done cleanup2"); 57039384277SMark Murray cleanup3: 57139384277SMark Murray krb5_free_context(pam_context); 57239384277SMark Murray PAM_LOG("Done cleanup3"); 57339384277SMark Murray 57439384277SMark Murray seteuid(euid); 57539384277SMark Murray setegid(egid); 57639384277SMark Murray 57739384277SMark Murray PAM_LOG("Done seteuid() & setegid()"); 57839384277SMark Murray 579545aa471SDag-Erling Smørgrav if (cache_name_buf != NULL) 580545aa471SDag-Erling Smørgrav free(cache_name_buf); 581545aa471SDag-Erling Smørgrav 58224fe7ba0SDag-Erling Smørgrav return (retval); 5832672e717SKen Smith #endif 58439384277SMark Murray } 58539384277SMark Murray 58639384277SMark Murray /* 58739384277SMark Murray * account management 58839384277SMark Murray */ 58939384277SMark Murray PAM_EXTERN int 59024fe7ba0SDag-Erling Smørgrav pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused, 591545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 59239384277SMark Murray { 59339384277SMark Murray krb5_error_code krbret; 59439384277SMark Murray krb5_context pam_context; 59539384277SMark Murray krb5_ccache ccache; 59639384277SMark Murray krb5_principal princ; 59739384277SMark Murray int retval; 598af9b4074SDag-Erling Smørgrav const void *user; 59964dbe1a7SDag-Erling Smørgrav const void *ccache_name; 60039384277SMark Murray 6014911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 60239384277SMark Murray if (retval != PAM_SUCCESS) 60324fe7ba0SDag-Erling Smørgrav return (retval); 60439384277SMark Murray 6054911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 60639384277SMark Murray 6074911b12cSDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &ccache_name); 6088dad14b1SDag-Erling Smørgrav if (retval != PAM_SUCCESS) 6098dad14b1SDag-Erling Smørgrav return (PAM_SUCCESS); 6108dad14b1SDag-Erling Smørgrav 6118dad14b1SDag-Erling Smørgrav PAM_LOG("Got credentials"); 6128dad14b1SDag-Erling Smørgrav 61339384277SMark Murray krbret = krb5_init_context(&pam_context); 61439384277SMark Murray if (krbret != 0) { 61588c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 61624fe7ba0SDag-Erling Smørgrav return (PAM_PERM_DENIED); 61739384277SMark Murray } 61839384277SMark Murray 61939384277SMark Murray PAM_LOG("Context initialised"); 62039384277SMark Murray 6214911b12cSDag-Erling Smørgrav krbret = krb5_cc_resolve(pam_context, (const char *)ccache_name, &ccache); 6227c2274dcSJacques Vidrine if (krbret != 0) { 6234911b12cSDag-Erling Smørgrav PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", (const char *)ccache_name, 6247c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 6257c2274dcSJacques Vidrine krb5_free_context(pam_context); 6267c2274dcSJacques Vidrine return (PAM_PERM_DENIED); 6277c2274dcSJacques Vidrine } 6287c2274dcSJacques Vidrine 6294911b12cSDag-Erling Smørgrav PAM_LOG("Got ccache %s", (const char *)ccache_name); 6307c2274dcSJacques Vidrine 6317c2274dcSJacques Vidrine 63239384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache, &princ); 63339384277SMark Murray if (krbret != 0) { 63488c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_get_principal(): %s", 63588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 63639384277SMark Murray retval = PAM_PERM_DENIED;; 63739384277SMark Murray goto cleanup; 63839384277SMark Murray } 63939384277SMark Murray 64039384277SMark Murray PAM_LOG("Got principal"); 64139384277SMark Murray 6424911b12cSDag-Erling Smørgrav if (krb5_kuserok(pam_context, princ, (const char *)user)) 64339384277SMark Murray retval = PAM_SUCCESS; 64439384277SMark Murray else 64539384277SMark Murray retval = PAM_PERM_DENIED; 64639384277SMark Murray krb5_free_principal(pam_context, princ); 64739384277SMark Murray 64839384277SMark Murray PAM_LOG("Done kuserok()"); 64939384277SMark Murray 65039384277SMark Murray cleanup: 65139384277SMark Murray krb5_free_context(pam_context); 65239384277SMark Murray PAM_LOG("Done cleanup"); 65339384277SMark Murray 65424fe7ba0SDag-Erling Smørgrav return (retval); 65539384277SMark Murray 65639384277SMark Murray } 65739384277SMark Murray 65839384277SMark Murray /* 65939384277SMark Murray * password management 66039384277SMark Murray */ 66139384277SMark Murray PAM_EXTERN int 66224fe7ba0SDag-Erling Smørgrav pam_sm_chauthtok(pam_handle_t *pamh, int flags, 663545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 66439384277SMark Murray { 66539384277SMark Murray krb5_error_code krbret; 66639384277SMark Murray krb5_context pam_context; 66739384277SMark Murray krb5_creds creds; 66839384277SMark Murray krb5_principal princ; 66939384277SMark Murray krb5_get_init_creds_opt opts; 67039384277SMark Murray krb5_data result_code_string, result_string; 67139384277SMark Murray int result_code, retval; 6724911b12cSDag-Erling Smørgrav const char *pass; 6734911b12cSDag-Erling Smørgrav const void *user; 674111ccd25SDag-Erling Smørgrav char *princ_name, *passdup; 67539384277SMark Murray 67639384277SMark Murray if (!(flags & PAM_UPDATE_AUTHTOK)) 67724fe7ba0SDag-Erling Smørgrav return (PAM_AUTHTOK_ERR); 67839384277SMark Murray 6794911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 68039384277SMark Murray if (retval != PAM_SUCCESS) 68124fe7ba0SDag-Erling Smørgrav return (retval); 68239384277SMark Murray 6834911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 68439384277SMark Murray 68539384277SMark Murray krbret = krb5_init_context(&pam_context); 68639384277SMark Murray if (krbret != 0) { 68788c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 68824fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 68939384277SMark Murray } 69039384277SMark Murray 69139384277SMark Murray PAM_LOG("Context initialised"); 69239384277SMark Murray 69339384277SMark Murray krb5_get_init_creds_opt_init(&opts); 69439384277SMark Murray 69539384277SMark Murray PAM_LOG("Credentials options initialised"); 69639384277SMark Murray 69739384277SMark Murray /* Get principal name */ 6984911b12cSDag-Erling Smørgrav krbret = krb5_parse_name(pam_context, (const char *)user, &princ); 69939384277SMark Murray if (krbret != 0) { 70088c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 70188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 70239384277SMark Murray retval = PAM_USER_UNKNOWN; 70339384277SMark Murray goto cleanup3; 70439384277SMark Murray } 70539384277SMark Murray 70639384277SMark Murray /* Now convert the principal name into something human readable */ 70739384277SMark Murray princ_name = NULL; 70839384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 70939384277SMark Murray if (krbret != 0) { 71088c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 71188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 71239384277SMark Murray retval = PAM_SERVICE_ERR; 71339384277SMark Murray goto cleanup2; 71439384277SMark Murray } 71539384277SMark Murray 71639384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 71739384277SMark Murray 71839384277SMark Murray /* Get password */ 719111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_OLDAUTHTOK, &pass, PASSWORD_PROMPT); 72039384277SMark Murray if (retval != PAM_SUCCESS) 72139384277SMark Murray goto cleanup2; 72239384277SMark Murray 72339384277SMark Murray PAM_LOG("Got password"); 72439384277SMark Murray 72539384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 72639384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 72739384277SMark Murray pass, NULL, pamh, 0, "kadmin/changepw", &opts); 72839384277SMark Murray if (krbret != 0) { 729af9b4074SDag-Erling Smørgrav PAM_LOG("Error krb5_get_init_creds_password(): %s", 73088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 73139384277SMark Murray retval = PAM_AUTH_ERR; 73239384277SMark Murray goto cleanup2; 73339384277SMark Murray } 73439384277SMark Murray 73539384277SMark Murray PAM_LOG("Credentials established"); 73639384277SMark Murray 73739384277SMark Murray /* Now get the new password */ 738111ccd25SDag-Erling Smørgrav for (;;) { 739111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, 740111ccd25SDag-Erling Smørgrav PAM_AUTHTOK, &pass, NEW_PASSWORD_PROMPT); 741111ccd25SDag-Erling Smørgrav if (retval != PAM_TRY_AGAIN) 742111ccd25SDag-Erling Smørgrav break; 743111ccd25SDag-Erling Smørgrav pam_error(pamh, "Mismatch; try again, EOF to quit."); 74439384277SMark Murray } 745111ccd25SDag-Erling Smørgrav if (retval != PAM_SUCCESS) 746111ccd25SDag-Erling Smørgrav goto cleanup; 74739384277SMark Murray 748111ccd25SDag-Erling Smørgrav PAM_LOG("Got new password"); 74939384277SMark Murray 75039384277SMark Murray /* Change it */ 751111ccd25SDag-Erling Smørgrav if ((passdup = strdup(pass)) == NULL) { 752111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 753111ccd25SDag-Erling Smørgrav goto cleanup; 754111ccd25SDag-Erling Smørgrav } 755111ccd25SDag-Erling Smørgrav krbret = krb5_change_password(pam_context, &creds, passdup, 75639384277SMark Murray &result_code, &result_code_string, &result_string); 757111ccd25SDag-Erling Smørgrav free(passdup); 75839384277SMark Murray if (krbret != 0) { 75939384277SMark Murray PAM_LOG("Error krb5_change_password(): %s", 76088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 76139384277SMark Murray retval = PAM_AUTHTOK_ERR; 76239384277SMark Murray goto cleanup; 76339384277SMark Murray } 76439384277SMark Murray if (result_code) { 76539384277SMark Murray PAM_LOG("Error krb5_change_password(): (result_code)"); 76639384277SMark Murray retval = PAM_AUTHTOK_ERR; 76739384277SMark Murray goto cleanup; 76839384277SMark Murray } 76939384277SMark Murray 77039384277SMark Murray PAM_LOG("Password changed"); 77139384277SMark Murray 77239384277SMark Murray if (result_string.data) 77339384277SMark Murray free(result_string.data); 77439384277SMark Murray if (result_code_string.data) 77539384277SMark Murray free(result_code_string.data); 77639384277SMark Murray 77739384277SMark Murray cleanup: 77839384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 77939384277SMark Murray PAM_LOG("Done cleanup"); 78039384277SMark Murray cleanup2: 78139384277SMark Murray krb5_free_principal(pam_context, princ); 78239384277SMark Murray PAM_LOG("Done cleanup2"); 78339384277SMark Murray cleanup3: 78439384277SMark Murray if (princ_name) 78539384277SMark Murray free(princ_name); 78639384277SMark Murray 78739384277SMark Murray krb5_free_context(pam_context); 78839384277SMark Murray 78939384277SMark Murray PAM_LOG("Done cleanup3"); 79039384277SMark Murray 79124fe7ba0SDag-Erling Smørgrav return (retval); 79239384277SMark Murray } 79339384277SMark Murray 79439384277SMark Murray PAM_MODULE_ENTRY("pam_krb5"); 79539384277SMark Murray 79639384277SMark Murray /* 79739384277SMark Murray * This routine with some modification is from the MIT V5B6 appl/bsd/login.c 79839384277SMark Murray * Modified by Sam Hartman <hartmans@mit.edu> to support PAM services 79939384277SMark Murray * for Debian. 80039384277SMark Murray * 80139384277SMark Murray * Verify the Kerberos ticket-granting ticket just retrieved for the 80239384277SMark Murray * user. If the Kerberos server doesn't respond, assume the user is 80339384277SMark Murray * trying to fake us out (since we DID just get a TGT from what is 80439384277SMark Murray * supposedly our KDC). If the host/<host> service is unknown (i.e., 80539384277SMark Murray * the local keytab doesn't have it), and we cannot find another 80639384277SMark Murray * service we do have, let her in. 80739384277SMark Murray * 80839384277SMark Murray * Returns 1 for confirmation, -1 for failure, 0 for uncertainty. 80939384277SMark Murray */ 810b4240e6cSMark Murray /* ARGSUSED */ 81139384277SMark Murray static int 81239384277SMark Murray verify_krb_v5_tgt(krb5_context context, krb5_ccache ccache, 81339384277SMark Murray char *pam_service, int debug) 81439384277SMark Murray { 81539384277SMark Murray krb5_error_code retval; 81639384277SMark Murray krb5_principal princ; 81739384277SMark Murray krb5_keyblock *keyblock; 81839384277SMark Murray krb5_data packet; 81939384277SMark Murray krb5_auth_context auth_context; 820c2065008SMark Murray char phost[BUFSIZ]; 821c2065008SMark Murray const char *services[3], **service; 82239384277SMark Murray 82339384277SMark Murray packet.data = 0; 82439384277SMark Murray 82539384277SMark Murray /* If possible we want to try and verify the ticket we have 82639384277SMark Murray * received against a keytab. We will try multiple service 82739384277SMark Murray * principals, including at least the host principal and the PAM 82839384277SMark Murray * service principal. The host principal is preferred because access 82939384277SMark Murray * to that key is generally sufficient to compromise root, while the 83039384277SMark Murray * service key for this PAM service may be less carefully guarded. 83139384277SMark Murray * It is important to check the keytab first before the KDC so we do 83239384277SMark Murray * not get spoofed by a fake KDC. 83339384277SMark Murray */ 83439384277SMark Murray services[0] = "host"; 83539384277SMark Murray services[1] = pam_service; 83639384277SMark Murray services[2] = NULL; 83739384277SMark Murray keyblock = 0; 83839384277SMark Murray retval = -1; 83939384277SMark Murray for (service = &services[0]; *service != NULL; service++) { 84039384277SMark Murray retval = krb5_sname_to_principal(context, NULL, *service, 84139384277SMark Murray KRB5_NT_SRV_HST, &princ); 84239384277SMark Murray if (retval != 0) { 84339384277SMark Murray if (debug) 84488c8bcceSJacques Vidrine syslog(LOG_DEBUG, 84588c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 84688c8bcceSJacques Vidrine "krb5_sname_to_principal()", 84788c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 84839384277SMark Murray return -1; 84939384277SMark Murray } 85039384277SMark Murray 85139384277SMark Murray /* Extract the name directly. */ 85239384277SMark Murray strncpy(phost, compat_princ_component(context, princ, 1), 85339384277SMark Murray BUFSIZ); 85439384277SMark Murray phost[BUFSIZ - 1] = '\0'; 85539384277SMark Murray 85639384277SMark Murray /* 85739384277SMark Murray * Do we have service/<host> keys? 85839384277SMark Murray * (use default/configured keytab, kvno IGNORE_VNO to get the 85939384277SMark Murray * first match, and ignore enctype.) 86039384277SMark Murray */ 86139384277SMark Murray retval = krb5_kt_read_service_key(context, NULL, princ, 0, 0, 86239384277SMark Murray &keyblock); 86339384277SMark Murray if (retval != 0) 86439384277SMark Murray continue; 86539384277SMark Murray break; 86639384277SMark Murray } 86739384277SMark Murray if (retval != 0) { /* failed to find key */ 86839384277SMark Murray /* Keytab or service key does not exist */ 86939384277SMark Murray if (debug) 87088c8bcceSJacques Vidrine syslog(LOG_DEBUG, 87188c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 87288c8bcceSJacques Vidrine "krb5_kt_read_service_key()", 87388c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 87439384277SMark Murray retval = 0; 87539384277SMark Murray goto cleanup; 87639384277SMark Murray } 87739384277SMark Murray if (keyblock) 87839384277SMark Murray krb5_free_keyblock(context, keyblock); 87939384277SMark Murray 88039384277SMark Murray /* Talk to the kdc and construct the ticket. */ 88139384277SMark Murray auth_context = NULL; 88239384277SMark Murray retval = krb5_mk_req(context, &auth_context, 0, *service, phost, 88339384277SMark Murray NULL, ccache, &packet); 88439384277SMark Murray if (auth_context) { 88539384277SMark Murray krb5_auth_con_free(context, auth_context); 88639384277SMark Murray auth_context = NULL; /* setup for rd_req */ 88739384277SMark Murray } 88839384277SMark Murray if (retval) { 88939384277SMark Murray if (debug) 89088c8bcceSJacques Vidrine syslog(LOG_DEBUG, 89188c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 89288c8bcceSJacques Vidrine "krb5_mk_req()", 89388c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 89439384277SMark Murray retval = -1; 89539384277SMark Murray goto cleanup; 89639384277SMark Murray } 89739384277SMark Murray 89839384277SMark Murray /* Try to use the ticket. */ 89939384277SMark Murray retval = krb5_rd_req(context, &auth_context, &packet, princ, NULL, 90039384277SMark Murray NULL, NULL); 90139384277SMark Murray if (retval) { 90239384277SMark Murray if (debug) 90388c8bcceSJacques Vidrine syslog(LOG_DEBUG, 90488c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 90588c8bcceSJacques Vidrine "krb5_rd_req()", 90688c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 90739384277SMark Murray retval = -1; 90839384277SMark Murray } 90939384277SMark Murray else 91039384277SMark Murray retval = 1; 91139384277SMark Murray 91239384277SMark Murray cleanup: 91339384277SMark Murray if (packet.data) 91439384277SMark Murray compat_free_data_contents(context, &packet); 91539384277SMark Murray krb5_free_principal(context, princ); 91639384277SMark Murray return retval; 91739384277SMark Murray } 91839384277SMark Murray 91939384277SMark Murray /* Free the memory for cache_name. Called by pam_end() */ 920b4240e6cSMark Murray /* ARGSUSED */ 92139384277SMark Murray static void 922c2065008SMark Murray cleanup_cache(pam_handle_t *pamh __unused, void *data, int pam_end_status __unused) 92339384277SMark Murray { 92439384277SMark Murray krb5_context pam_context; 92539384277SMark Murray krb5_ccache ccache; 9267c2274dcSJacques Vidrine krb5_error_code krbret; 92739384277SMark Murray 92839384277SMark Murray if (krb5_init_context(&pam_context)) 92939384277SMark Murray return; 93039384277SMark Murray 9317c2274dcSJacques Vidrine krbret = krb5_cc_resolve(pam_context, data, &ccache); 9327c2274dcSJacques Vidrine if (krbret == 0) 93339384277SMark Murray krb5_cc_destroy(pam_context, ccache); 93439384277SMark Murray krb5_free_context(pam_context); 9357c2274dcSJacques Vidrine free(data); 93639384277SMark Murray } 93739384277SMark Murray 93839384277SMark Murray #ifdef COMPAT_HEIMDAL 93939384277SMark Murray #ifdef COMPAT_MIT 94039384277SMark Murray #error This cannot be MIT and Heimdal compatible! 94139384277SMark Murray #endif 94239384277SMark Murray #endif 94339384277SMark Murray 94439384277SMark Murray #ifndef COMPAT_HEIMDAL 94539384277SMark Murray #ifndef COMPAT_MIT 94639384277SMark Murray #error One of COMPAT_MIT and COMPAT_HEIMDAL must be specified! 94739384277SMark Murray #endif 94839384277SMark Murray #endif 94939384277SMark Murray 95039384277SMark Murray #ifdef COMPAT_HEIMDAL 951b4240e6cSMark Murray /* ARGSUSED */ 95239384277SMark Murray static const char * 953c2065008SMark Murray compat_princ_component(krb5_context context __unused, krb5_principal princ, int n) 95439384277SMark Murray { 95539384277SMark Murray return princ->name.name_string.val[n]; 95639384277SMark Murray } 95739384277SMark Murray 958b4240e6cSMark Murray /* ARGSUSED */ 95939384277SMark Murray static void 960c2065008SMark Murray compat_free_data_contents(krb5_context context __unused, krb5_data * data) 96139384277SMark Murray { 96239384277SMark Murray krb5_xfree(data->data); 96339384277SMark Murray } 96439384277SMark Murray #endif 96539384277SMark Murray 96639384277SMark Murray #ifdef COMPAT_MIT 96739384277SMark Murray static const char * 96839384277SMark Murray compat_princ_component(krb5_context context, krb5_principal princ, int n) 96939384277SMark Murray { 97039384277SMark Murray return krb5_princ_component(context, princ, n)->data; 97139384277SMark Murray } 97239384277SMark Murray 97339384277SMark Murray static void 97439384277SMark Murray compat_free_data_contents(krb5_context context, krb5_data * data) 97539384277SMark Murray { 97639384277SMark Murray krb5_free_data_contents(context, data); 97739384277SMark Murray } 97839384277SMark Murray #endif 979