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. 94d6991c6SDag-Erling Smørgrav * Copyright (c) Networks Associates Technology, Inc., 2002-2003. 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" 89545aa471SDag-Erling Smørgrav #define PAM_OPT_FORWARDABLE "forwardable" 90545aa471SDag-Erling Smørgrav #define PAM_OPT_NO_CCACHE "no_ccache" 91545aa471SDag-Erling Smørgrav #define PAM_OPT_REUSE_CCACHE "reuse_ccache" 9239384277SMark Murray 9339384277SMark Murray /* 9439384277SMark Murray * authentication management 9539384277SMark Murray */ 9639384277SMark Murray PAM_EXTERN int 9724fe7ba0SDag-Erling Smørgrav pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 98545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 9939384277SMark Murray { 10039384277SMark Murray krb5_error_code krbret; 10139384277SMark Murray krb5_context pam_context; 10239384277SMark Murray krb5_creds creds; 10339384277SMark Murray krb5_principal princ; 1047c2274dcSJacques Vidrine krb5_ccache ccache; 10539384277SMark Murray krb5_get_init_creds_opt opts; 10639384277SMark Murray struct passwd *pwd; 10739384277SMark Murray int retval; 108af9b4074SDag-Erling Smørgrav void *ccache_data; 1094911b12cSDag-Erling Smørgrav const char *user, *pass; 110af9b4074SDag-Erling Smørgrav const void *sourceuser, *service; 1117c2274dcSJacques Vidrine char *principal, *princ_name, *ccache_name, luser[32], *srvdup; 11239384277SMark Murray 11339384277SMark Murray retval = pam_get_user(pamh, &user, USER_PROMPT); 11439384277SMark Murray if (retval != PAM_SUCCESS) 11524fe7ba0SDag-Erling Smørgrav return (retval); 11639384277SMark Murray 11739384277SMark Murray PAM_LOG("Got user: %s", user); 11839384277SMark Murray 1194911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_RUSER, &sourceuser); 12039384277SMark Murray if (retval != PAM_SUCCESS) 12124fe7ba0SDag-Erling Smørgrav return (retval); 12239384277SMark Murray 1234911b12cSDag-Erling Smørgrav PAM_LOG("Got ruser: %s", (const char *)sourceuser); 12439384277SMark Murray 12539384277SMark Murray service = NULL; 1264911b12cSDag-Erling Smørgrav pam_get_item(pamh, PAM_SERVICE, &service); 12739384277SMark Murray if (service == NULL) 12839384277SMark Murray service = "unknown"; 12939384277SMark Murray 1304911b12cSDag-Erling Smørgrav PAM_LOG("Got service: %s", (const char *)service); 13139384277SMark Murray 13239384277SMark Murray krbret = krb5_init_context(&pam_context); 13339384277SMark Murray if (krbret != 0) { 13439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 13524fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 13639384277SMark Murray } 13739384277SMark Murray 13839384277SMark Murray PAM_LOG("Context initialised"); 13939384277SMark Murray 14039384277SMark Murray krb5_get_init_creds_opt_init(&opts); 14139384277SMark Murray 142545aa471SDag-Erling Smørgrav if (openpam_get_option(pamh, PAM_OPT_FORWARDABLE)) 14339384277SMark Murray krb5_get_init_creds_opt_set_forwardable(&opts, 1); 14439384277SMark Murray 14539384277SMark Murray PAM_LOG("Credentials initialised"); 14639384277SMark Murray 14739384277SMark Murray krbret = krb5_cc_register(pam_context, &krb5_mcc_ops, FALSE); 14839384277SMark Murray if (krbret != 0 && krbret != KRB5_CC_TYPE_EXISTS) { 14939384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 15039384277SMark Murray retval = PAM_SERVICE_ERR; 15139384277SMark Murray goto cleanup3; 15239384277SMark Murray } 15339384277SMark Murray 15439384277SMark Murray PAM_LOG("Done krb5_cc_register()"); 15539384277SMark Murray 15639384277SMark Murray /* Get principal name */ 157545aa471SDag-Erling Smørgrav if (openpam_get_option(pamh, PAM_OPT_AUTH_AS_SELF)) 1584911b12cSDag-Erling Smørgrav asprintf(&principal, "%s/%s", (const char *)sourceuser, user); 15939384277SMark Murray else 16039384277SMark Murray principal = strdup(user); 16139384277SMark Murray 16239384277SMark Murray PAM_LOG("Created principal: %s", principal); 16339384277SMark Murray 16439384277SMark Murray krbret = krb5_parse_name(pam_context, principal, &princ); 16539384277SMark Murray free(principal); 16639384277SMark Murray if (krbret != 0) { 16788c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 16888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 16939384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 17039384277SMark Murray retval = PAM_SERVICE_ERR; 17139384277SMark Murray goto cleanup3; 17239384277SMark Murray } 17339384277SMark Murray 17439384277SMark Murray PAM_LOG("Done krb5_parse_name()"); 17539384277SMark Murray 17639384277SMark Murray /* Now convert the principal name into something human readable */ 17739384277SMark Murray princ_name = NULL; 17839384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 17939384277SMark Murray if (krbret != 0) { 18088c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 18188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 18239384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 18339384277SMark Murray retval = PAM_SERVICE_ERR; 18439384277SMark Murray goto cleanup2; 18539384277SMark Murray } 18639384277SMark Murray 18739384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 18839384277SMark Murray 18939384277SMark Murray /* Get password */ 190111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 19139384277SMark Murray if (retval != PAM_SUCCESS) 19239384277SMark Murray goto cleanup2; 19339384277SMark Murray 19439384277SMark Murray PAM_LOG("Got password"); 19539384277SMark Murray 19639384277SMark Murray /* Verify the local user exists (AFTER getting the password) */ 19739384277SMark Murray if (strchr(user, '@')) { 19839384277SMark Murray /* get a local account name for this principal */ 19939384277SMark Murray krbret = krb5_aname_to_localname(pam_context, princ, 20039384277SMark Murray sizeof(luser), luser); 20139384277SMark Murray if (krbret != 0) { 20239384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 20339384277SMark Murray PAM_LOG("Error krb5_aname_to_localname(): %s", 20488c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 20539384277SMark Murray retval = PAM_USER_UNKNOWN; 20639384277SMark Murray goto cleanup2; 20739384277SMark Murray } 20839384277SMark Murray 20939384277SMark Murray retval = pam_set_item(pamh, PAM_USER, luser); 21039384277SMark Murray if (retval != PAM_SUCCESS) 21139384277SMark Murray goto cleanup2; 21239384277SMark Murray 21339384277SMark Murray PAM_LOG("PAM_USER Redone"); 21439384277SMark Murray } 21539384277SMark Murray 21639384277SMark Murray pwd = getpwnam(user); 21739384277SMark Murray if (pwd == NULL) { 21839384277SMark Murray retval = PAM_USER_UNKNOWN; 21939384277SMark Murray goto cleanup2; 22039384277SMark Murray } 22139384277SMark Murray 22239384277SMark Murray PAM_LOG("Done getpwnam()"); 22339384277SMark Murray 22439384277SMark Murray /* Get a TGT */ 22539384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 22639384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 22739384277SMark Murray pass, NULL, pamh, 0, NULL, &opts); 22839384277SMark Murray if (krbret != 0) { 22939384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 23039384277SMark Murray PAM_LOG("Error krb5_get_init_creds_password(): %s", 23188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 23239384277SMark Murray retval = PAM_AUTH_ERR; 23339384277SMark Murray goto cleanup2; 23439384277SMark Murray } 23539384277SMark Murray 23639384277SMark Murray PAM_LOG("Got TGT"); 23739384277SMark Murray 2387c2274dcSJacques Vidrine /* Generate a temporary cache */ 2397c2274dcSJacques Vidrine krbret = krb5_cc_gen_new(pam_context, &krb5_mcc_ops, &ccache); 24039384277SMark Murray if (krbret != 0) { 24139384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 2427c2274dcSJacques Vidrine PAM_LOG("Error krb5_cc_gen_new(): %s", 24388c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 24439384277SMark Murray retval = PAM_SERVICE_ERR; 24539384277SMark Murray goto cleanup; 24639384277SMark Murray } 24739384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache, princ); 24839384277SMark Murray if (krbret != 0) { 24939384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 25088c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 25188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 25239384277SMark Murray retval = PAM_SERVICE_ERR; 25339384277SMark Murray goto cleanup; 25439384277SMark Murray } 25539384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache, &creds); 25639384277SMark Murray if (krbret != 0) { 25739384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 25888c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_store_cred(): %s", 25988c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 26039384277SMark Murray krb5_cc_destroy(pam_context, ccache); 26139384277SMark Murray retval = PAM_SERVICE_ERR; 26239384277SMark Murray goto cleanup; 26339384277SMark Murray } 26439384277SMark Murray 26539384277SMark Murray PAM_LOG("Credentials stashed"); 26639384277SMark Murray 26739384277SMark Murray /* Verify them */ 268111ccd25SDag-Erling Smørgrav if ((srvdup = strdup(service)) == NULL) { 269111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 270111ccd25SDag-Erling Smørgrav goto cleanup; 271111ccd25SDag-Erling Smørgrav } 272111ccd25SDag-Erling Smørgrav krbret = verify_krb_v5_tgt(pam_context, ccache, srvdup, 273545aa471SDag-Erling Smørgrav openpam_get_option(pamh, PAM_OPT_FORWARDABLE) ? 1 : 0); 274111ccd25SDag-Erling Smørgrav free(srvdup); 275111ccd25SDag-Erling Smørgrav if (krbret == -1) { 27639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 27739384277SMark Murray krb5_cc_destroy(pam_context, ccache); 27839384277SMark Murray retval = PAM_AUTH_ERR; 27939384277SMark Murray goto cleanup; 28039384277SMark Murray } 28139384277SMark Murray 28239384277SMark Murray PAM_LOG("Credentials stash verified"); 28339384277SMark Murray 284af9b4074SDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &ccache_data); 28539384277SMark Murray if (retval == PAM_SUCCESS) { 28639384277SMark Murray krb5_cc_destroy(pam_context, ccache); 28739384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 28839384277SMark Murray retval = PAM_AUTH_ERR; 28939384277SMark Murray goto cleanup; 29039384277SMark Murray } 29139384277SMark Murray 29239384277SMark Murray PAM_LOG("Credentials stash not pre-existing"); 29339384277SMark Murray 2947c2274dcSJacques Vidrine asprintf(&ccache_name, "%s:%s", krb5_cc_get_type(pam_context, 2957c2274dcSJacques Vidrine ccache), krb5_cc_get_name(pam_context, ccache)); 2967c2274dcSJacques Vidrine if (ccache_name == NULL) { 2977c2274dcSJacques Vidrine PAM_VERBOSE_ERROR("Kerberos 5 error"); 2987c2274dcSJacques Vidrine retval = PAM_BUF_ERR; 2997c2274dcSJacques Vidrine goto cleanup; 3007c2274dcSJacques Vidrine } 3017c2274dcSJacques Vidrine retval = pam_set_data(pamh, "ccache", ccache_name, cleanup_cache); 30239384277SMark Murray if (retval != 0) { 30339384277SMark Murray krb5_cc_destroy(pam_context, ccache); 30439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 30539384277SMark Murray retval = PAM_SERVICE_ERR; 30639384277SMark Murray goto cleanup; 30739384277SMark Murray } 30839384277SMark Murray 30939384277SMark Murray PAM_LOG("Credentials stash saved"); 31039384277SMark Murray 31139384277SMark Murray cleanup: 31239384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 31339384277SMark Murray PAM_LOG("Done cleanup"); 31439384277SMark Murray cleanup2: 31539384277SMark Murray krb5_free_principal(pam_context, princ); 31639384277SMark Murray PAM_LOG("Done cleanup2"); 31739384277SMark Murray cleanup3: 31839384277SMark Murray if (princ_name) 31939384277SMark Murray free(princ_name); 32039384277SMark Murray 32139384277SMark Murray krb5_free_context(pam_context); 32239384277SMark Murray 32339384277SMark Murray PAM_LOG("Done cleanup3"); 32439384277SMark Murray 32539384277SMark Murray if (retval != PAM_SUCCESS) 32639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 refuses you"); 32739384277SMark Murray 32824fe7ba0SDag-Erling Smørgrav return (retval); 32939384277SMark Murray } 33039384277SMark Murray 33139384277SMark Murray PAM_EXTERN int 33224fe7ba0SDag-Erling Smørgrav pam_sm_setcred(pam_handle_t *pamh, int flags, 333545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 33439384277SMark Murray { 33539384277SMark Murray 33639384277SMark Murray krb5_error_code krbret; 33739384277SMark Murray krb5_context pam_context; 33839384277SMark Murray krb5_principal princ; 33939384277SMark Murray krb5_creds creds; 34039384277SMark Murray krb5_ccache ccache_temp, ccache_perm; 34139384277SMark Murray krb5_cc_cursor cursor; 34239384277SMark Murray struct passwd *pwd = NULL; 34339384277SMark Murray int retval; 3444911b12cSDag-Erling Smørgrav const char *cache_name, *q; 345af9b4074SDag-Erling Smørgrav const void *user; 346af9b4074SDag-Erling Smørgrav void *cache_data; 347545aa471SDag-Erling Smørgrav char *cache_name_buf = NULL, *p; 34839384277SMark Murray 34939384277SMark Murray uid_t euid; 35039384277SMark Murray gid_t egid; 35139384277SMark Murray 35239384277SMark Murray if (flags & PAM_DELETE_CRED) 35324fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 35439384277SMark Murray 35539384277SMark Murray if (flags & PAM_REFRESH_CRED) 35624fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 35739384277SMark Murray 35839384277SMark Murray if (flags & PAM_REINITIALIZE_CRED) 35924fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 36039384277SMark Murray 36139384277SMark Murray if (!(flags & PAM_ESTABLISH_CRED)) 36224fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 36339384277SMark Murray 36439384277SMark Murray PAM_LOG("Establishing credentials"); 36539384277SMark Murray 36639384277SMark Murray /* Get username */ 3674911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 36839384277SMark Murray if (retval != PAM_SUCCESS) 36924fe7ba0SDag-Erling Smørgrav return (retval); 37039384277SMark Murray 3714911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 37239384277SMark Murray 37339384277SMark Murray krbret = krb5_init_context(&pam_context); 37439384277SMark Murray if (krbret != 0) { 37588c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 37624fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 37739384277SMark Murray } 37839384277SMark Murray 37939384277SMark Murray PAM_LOG("Context initialised"); 38039384277SMark Murray 38139384277SMark Murray euid = geteuid(); /* Usually 0 */ 38239384277SMark Murray egid = getegid(); 38339384277SMark Murray 38439384277SMark Murray PAM_LOG("Got euid, egid: %d %d", euid, egid); 38539384277SMark Murray 3867c2274dcSJacques Vidrine /* Retrieve the temporary cache */ 3874911b12cSDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &cache_data); 3888f857e88SJacques Vidrine if (retval != PAM_SUCCESS) { 3898f857e88SJacques Vidrine retval = PAM_CRED_UNAVAIL; 39039384277SMark Murray goto cleanup3; 3918f857e88SJacques Vidrine } 3924911b12cSDag-Erling Smørgrav krbret = krb5_cc_resolve(pam_context, cache_data, &ccache_temp); 3937c2274dcSJacques Vidrine if (krbret != 0) { 3944911b12cSDag-Erling Smørgrav PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", (const char *)cache_data, 3957c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 3968f857e88SJacques Vidrine retval = PAM_SERVICE_ERR; 3977c2274dcSJacques Vidrine goto cleanup3; 3987c2274dcSJacques Vidrine } 39939384277SMark Murray 40039384277SMark Murray /* Get the uid. This should exist. */ 40139384277SMark Murray pwd = getpwnam(user); 40239384277SMark Murray if (pwd == NULL) { 40339384277SMark Murray retval = PAM_USER_UNKNOWN; 40439384277SMark Murray goto cleanup3; 40539384277SMark Murray } 40639384277SMark Murray 40739384277SMark Murray PAM_LOG("Done getpwnam()"); 40839384277SMark Murray 40939384277SMark Murray /* Avoid following a symlink as root */ 41039384277SMark Murray if (setegid(pwd->pw_gid)) { 41139384277SMark Murray retval = PAM_SERVICE_ERR; 41239384277SMark Murray goto cleanup3; 41339384277SMark Murray } 41439384277SMark Murray if (seteuid(pwd->pw_uid)) { 41539384277SMark Murray retval = PAM_SERVICE_ERR; 41639384277SMark Murray goto cleanup3; 41739384277SMark Murray } 41839384277SMark Murray 41939384277SMark Murray PAM_LOG("Done setegid() & seteuid()"); 42039384277SMark Murray 42139384277SMark Murray /* Get the cache name */ 422545aa471SDag-Erling Smørgrav cache_name = openpam_get_option(pamh, PAM_OPT_CCACHE); 423545aa471SDag-Erling Smørgrav if (cache_name == NULL) { 424545aa471SDag-Erling Smørgrav asprintf(&cache_name_buf, "FILE:/tmp/krb5cc_%d", pwd->pw_uid); 425545aa471SDag-Erling Smørgrav cache_name = cache_name_buf; 426545aa471SDag-Erling Smørgrav } 42739384277SMark Murray 42839384277SMark Murray p = calloc(PATH_MAX + 16, sizeof(char)); 42939384277SMark Murray q = cache_name; 43039384277SMark Murray 43139384277SMark Murray if (p == NULL) { 43239384277SMark Murray PAM_LOG("Error malloc(): failure"); 43339384277SMark Murray retval = PAM_BUF_ERR; 43439384277SMark Murray goto cleanup3; 43539384277SMark Murray } 43639384277SMark Murray cache_name = p; 43739384277SMark Murray 43839384277SMark Murray /* convert %u and %p */ 43939384277SMark Murray while (*q) { 44039384277SMark Murray if (*q == '%') { 44139384277SMark Murray q++; 44239384277SMark Murray if (*q == 'u') { 44339384277SMark Murray sprintf(p, "%d", pwd->pw_uid); 44439384277SMark Murray p += strlen(p); 44539384277SMark Murray } 44639384277SMark Murray else if (*q == 'p') { 44739384277SMark Murray sprintf(p, "%d", getpid()); 44839384277SMark Murray p += strlen(p); 44939384277SMark Murray } 45039384277SMark Murray else { 45139384277SMark Murray /* Not a special token */ 45239384277SMark Murray *p++ = '%'; 45339384277SMark Murray q--; 45439384277SMark Murray } 45539384277SMark Murray q++; 45639384277SMark Murray } 45739384277SMark Murray else { 45839384277SMark Murray *p++ = *q++; 45939384277SMark Murray } 46039384277SMark Murray } 46139384277SMark Murray 46239384277SMark Murray PAM_LOG("Got cache_name: %s", cache_name); 46339384277SMark Murray 46439384277SMark Murray /* Initialize the new ccache */ 46539384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache_temp, &princ); 46639384277SMark Murray if (krbret != 0) { 46739384277SMark Murray PAM_LOG("Error krb5_cc_get_principal(): %s", 46888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 46939384277SMark Murray retval = PAM_SERVICE_ERR; 47039384277SMark Murray goto cleanup3; 47139384277SMark Murray } 47239384277SMark Murray krbret = krb5_cc_resolve(pam_context, cache_name, &ccache_perm); 47339384277SMark Murray if (krbret != 0) { 47488c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_resolve(): %s", 47588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 47639384277SMark Murray retval = PAM_SERVICE_ERR; 47739384277SMark Murray goto cleanup2; 47839384277SMark Murray } 47939384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache_perm, princ); 48039384277SMark Murray if (krbret != 0) { 48188c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 48288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 48339384277SMark Murray retval = PAM_SERVICE_ERR; 48439384277SMark Murray goto cleanup2; 48539384277SMark Murray } 48639384277SMark Murray 48739384277SMark Murray PAM_LOG("Cache initialised"); 48839384277SMark Murray 48939384277SMark Murray /* Prepare for iteration over creds */ 49039384277SMark Murray krbret = krb5_cc_start_seq_get(pam_context, ccache_temp, &cursor); 49139384277SMark Murray if (krbret != 0) { 49288c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_start_seq_get(): %s", 49388c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 49439384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 49539384277SMark Murray retval = PAM_SERVICE_ERR; 49639384277SMark Murray goto cleanup2; 49739384277SMark Murray } 49839384277SMark Murray 49939384277SMark Murray PAM_LOG("Prepared for iteration"); 50039384277SMark Murray 50139384277SMark Murray /* Copy the creds (should be two of them) */ 50239384277SMark Murray while ((krbret = krb5_cc_next_cred(pam_context, ccache_temp, 50339384277SMark Murray &cursor, &creds) == 0)) { 50439384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache_perm, &creds); 50539384277SMark Murray if (krbret != 0) { 50639384277SMark Murray PAM_LOG("Error krb5_cc_store_cred(): %s", 50788c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 50839384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 50939384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 51039384277SMark Murray retval = PAM_SERVICE_ERR; 51139384277SMark Murray goto cleanup2; 51239384277SMark Murray } 51339384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 51439384277SMark Murray PAM_LOG("Iteration"); 51539384277SMark Murray } 51639384277SMark Murray krb5_cc_end_seq_get(pam_context, ccache_temp, &cursor); 51739384277SMark Murray 51839384277SMark Murray PAM_LOG("Done iterating"); 51939384277SMark Murray 52039384277SMark Murray if (strstr(cache_name, "FILE:") == cache_name) { 52139384277SMark Murray if (chown(&cache_name[5], pwd->pw_uid, pwd->pw_gid) == -1) { 52239384277SMark Murray PAM_LOG("Error chown(): %s", strerror(errno)); 52339384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 52439384277SMark Murray retval = PAM_SERVICE_ERR; 52539384277SMark Murray goto cleanup2; 52639384277SMark Murray } 52739384277SMark Murray PAM_LOG("Done chown()"); 52839384277SMark Murray 52939384277SMark Murray if (chmod(&cache_name[5], (S_IRUSR | S_IWUSR)) == -1) { 53039384277SMark Murray PAM_LOG("Error chmod(): %s", strerror(errno)); 53139384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 53239384277SMark Murray retval = PAM_SERVICE_ERR; 53339384277SMark Murray goto cleanup2; 53439384277SMark Murray } 53539384277SMark Murray PAM_LOG("Done chmod()"); 53639384277SMark Murray } 53739384277SMark Murray 53839384277SMark Murray krb5_cc_close(pam_context, ccache_perm); 53939384277SMark Murray 54039384277SMark Murray PAM_LOG("Cache closed"); 54139384277SMark Murray 542545aa471SDag-Erling Smørgrav retval = pam_setenv(pamh, "KRB5CCNAME", cache_name, 1); 543545aa471SDag-Erling Smørgrav if (retval != PAM_SUCCESS) { 544545aa471SDag-Erling Smørgrav PAM_LOG("Error pam_setenv(): %s", pam_strerror(pamh, retval)); 54539384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 54639384277SMark Murray retval = PAM_SERVICE_ERR; 54739384277SMark Murray goto cleanup2; 54839384277SMark Murray } 54939384277SMark Murray 55039384277SMark Murray PAM_LOG("Environment done: KRB5CCNAME=%s", cache_name); 55139384277SMark Murray 55239384277SMark Murray cleanup2: 55339384277SMark Murray krb5_free_principal(pam_context, princ); 55439384277SMark Murray PAM_LOG("Done cleanup2"); 55539384277SMark Murray cleanup3: 55639384277SMark Murray krb5_free_context(pam_context); 55739384277SMark Murray PAM_LOG("Done cleanup3"); 55839384277SMark Murray 55939384277SMark Murray seteuid(euid); 56039384277SMark Murray setegid(egid); 56139384277SMark Murray 56239384277SMark Murray PAM_LOG("Done seteuid() & setegid()"); 56339384277SMark Murray 564545aa471SDag-Erling Smørgrav if (cache_name_buf != NULL) 565545aa471SDag-Erling Smørgrav free(cache_name_buf); 566545aa471SDag-Erling Smørgrav 56724fe7ba0SDag-Erling Smørgrav return (retval); 56839384277SMark Murray } 56939384277SMark Murray 57039384277SMark Murray /* 57139384277SMark Murray * account management 57239384277SMark Murray */ 57339384277SMark Murray PAM_EXTERN int 57424fe7ba0SDag-Erling Smørgrav pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused, 575545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 57639384277SMark Murray { 57739384277SMark Murray krb5_error_code krbret; 57839384277SMark Murray krb5_context pam_context; 57939384277SMark Murray krb5_ccache ccache; 58039384277SMark Murray krb5_principal princ; 58139384277SMark Murray int retval; 582af9b4074SDag-Erling Smørgrav const void *user; 583af9b4074SDag-Erling Smørgrav void *ccache_name; 58439384277SMark Murray 5854911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 58639384277SMark Murray if (retval != PAM_SUCCESS) 58724fe7ba0SDag-Erling Smørgrav return (retval); 58839384277SMark Murray 5894911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 59039384277SMark Murray 5914911b12cSDag-Erling Smørgrav retval = pam_get_data(pamh, "ccache", &ccache_name); 5928dad14b1SDag-Erling Smørgrav if (retval != PAM_SUCCESS) 5938dad14b1SDag-Erling Smørgrav return (PAM_SUCCESS); 5948dad14b1SDag-Erling Smørgrav 5958dad14b1SDag-Erling Smørgrav PAM_LOG("Got credentials"); 5968dad14b1SDag-Erling Smørgrav 59739384277SMark Murray krbret = krb5_init_context(&pam_context); 59839384277SMark Murray if (krbret != 0) { 59988c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 60024fe7ba0SDag-Erling Smørgrav return (PAM_PERM_DENIED); 60139384277SMark Murray } 60239384277SMark Murray 60339384277SMark Murray PAM_LOG("Context initialised"); 60439384277SMark Murray 6054911b12cSDag-Erling Smørgrav krbret = krb5_cc_resolve(pam_context, (const char *)ccache_name, &ccache); 6067c2274dcSJacques Vidrine if (krbret != 0) { 6074911b12cSDag-Erling Smørgrav PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", (const char *)ccache_name, 6087c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 6097c2274dcSJacques Vidrine krb5_free_context(pam_context); 6107c2274dcSJacques Vidrine return (PAM_PERM_DENIED); 6117c2274dcSJacques Vidrine } 6127c2274dcSJacques Vidrine 6134911b12cSDag-Erling Smørgrav PAM_LOG("Got ccache %s", (const char *)ccache_name); 6147c2274dcSJacques Vidrine 6157c2274dcSJacques Vidrine 61639384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache, &princ); 61739384277SMark Murray if (krbret != 0) { 61888c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_get_principal(): %s", 61988c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 62039384277SMark Murray retval = PAM_PERM_DENIED;; 62139384277SMark Murray goto cleanup; 62239384277SMark Murray } 62339384277SMark Murray 62439384277SMark Murray PAM_LOG("Got principal"); 62539384277SMark Murray 6264911b12cSDag-Erling Smørgrav if (krb5_kuserok(pam_context, princ, (const char *)user)) 62739384277SMark Murray retval = PAM_SUCCESS; 62839384277SMark Murray else 62939384277SMark Murray retval = PAM_PERM_DENIED; 63039384277SMark Murray krb5_free_principal(pam_context, princ); 63139384277SMark Murray 63239384277SMark Murray PAM_LOG("Done kuserok()"); 63339384277SMark Murray 63439384277SMark Murray cleanup: 63539384277SMark Murray krb5_free_context(pam_context); 63639384277SMark Murray PAM_LOG("Done cleanup"); 63739384277SMark Murray 63824fe7ba0SDag-Erling Smørgrav return (retval); 63939384277SMark Murray 64039384277SMark Murray } 64139384277SMark Murray 64239384277SMark Murray /* 64339384277SMark Murray * password management 64439384277SMark Murray */ 64539384277SMark Murray PAM_EXTERN int 64624fe7ba0SDag-Erling Smørgrav pam_sm_chauthtok(pam_handle_t *pamh, int flags, 647545aa471SDag-Erling Smørgrav int argc __unused, const char *argv[] __unused) 64839384277SMark Murray { 64939384277SMark Murray krb5_error_code krbret; 65039384277SMark Murray krb5_context pam_context; 65139384277SMark Murray krb5_creds creds; 65239384277SMark Murray krb5_principal princ; 65339384277SMark Murray krb5_get_init_creds_opt opts; 65439384277SMark Murray krb5_data result_code_string, result_string; 65539384277SMark Murray int result_code, retval; 6564911b12cSDag-Erling Smørgrav const char *pass; 6574911b12cSDag-Erling Smørgrav const void *user; 658111ccd25SDag-Erling Smørgrav char *princ_name, *passdup; 65939384277SMark Murray 66039384277SMark Murray if (!(flags & PAM_UPDATE_AUTHTOK)) 66124fe7ba0SDag-Erling Smørgrav return (PAM_AUTHTOK_ERR); 66239384277SMark Murray 6634911b12cSDag-Erling Smørgrav retval = pam_get_item(pamh, PAM_USER, &user); 66439384277SMark Murray if (retval != PAM_SUCCESS) 66524fe7ba0SDag-Erling Smørgrav return (retval); 66639384277SMark Murray 6674911b12cSDag-Erling Smørgrav PAM_LOG("Got user: %s", (const char *)user); 66839384277SMark Murray 66939384277SMark Murray krbret = krb5_init_context(&pam_context); 67039384277SMark Murray if (krbret != 0) { 67188c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 67224fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 67339384277SMark Murray } 67439384277SMark Murray 67539384277SMark Murray PAM_LOG("Context initialised"); 67639384277SMark Murray 67739384277SMark Murray krb5_get_init_creds_opt_init(&opts); 67839384277SMark Murray 67939384277SMark Murray PAM_LOG("Credentials options initialised"); 68039384277SMark Murray 68139384277SMark Murray /* Get principal name */ 6824911b12cSDag-Erling Smørgrav krbret = krb5_parse_name(pam_context, (const char *)user, &princ); 68339384277SMark Murray if (krbret != 0) { 68488c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 68588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 68639384277SMark Murray retval = PAM_USER_UNKNOWN; 68739384277SMark Murray goto cleanup3; 68839384277SMark Murray } 68939384277SMark Murray 69039384277SMark Murray /* Now convert the principal name into something human readable */ 69139384277SMark Murray princ_name = NULL; 69239384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 69339384277SMark Murray if (krbret != 0) { 69488c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 69588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 69639384277SMark Murray retval = PAM_SERVICE_ERR; 69739384277SMark Murray goto cleanup2; 69839384277SMark Murray } 69939384277SMark Murray 70039384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 70139384277SMark Murray 70239384277SMark Murray /* Get password */ 703111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_OLDAUTHTOK, &pass, PASSWORD_PROMPT); 70439384277SMark Murray if (retval != PAM_SUCCESS) 70539384277SMark Murray goto cleanup2; 70639384277SMark Murray 70739384277SMark Murray PAM_LOG("Got password"); 70839384277SMark Murray 70939384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 71039384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 71139384277SMark Murray pass, NULL, pamh, 0, "kadmin/changepw", &opts); 71239384277SMark Murray if (krbret != 0) { 713af9b4074SDag-Erling Smørgrav PAM_LOG("Error krb5_get_init_creds_password(): %s", 71488c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 71539384277SMark Murray retval = PAM_AUTH_ERR; 71639384277SMark Murray goto cleanup2; 71739384277SMark Murray } 71839384277SMark Murray 71939384277SMark Murray PAM_LOG("Credentials established"); 72039384277SMark Murray 72139384277SMark Murray /* Now get the new password */ 722111ccd25SDag-Erling Smørgrav for (;;) { 723111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, 724111ccd25SDag-Erling Smørgrav PAM_AUTHTOK, &pass, NEW_PASSWORD_PROMPT); 725111ccd25SDag-Erling Smørgrav if (retval != PAM_TRY_AGAIN) 726111ccd25SDag-Erling Smørgrav break; 727111ccd25SDag-Erling Smørgrav pam_error(pamh, "Mismatch; try again, EOF to quit."); 72839384277SMark Murray } 729111ccd25SDag-Erling Smørgrav if (retval != PAM_SUCCESS) 730111ccd25SDag-Erling Smørgrav goto cleanup; 73139384277SMark Murray 732111ccd25SDag-Erling Smørgrav PAM_LOG("Got new password"); 73339384277SMark Murray 73439384277SMark Murray /* Change it */ 735111ccd25SDag-Erling Smørgrav if ((passdup = strdup(pass)) == NULL) { 736111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 737111ccd25SDag-Erling Smørgrav goto cleanup; 738111ccd25SDag-Erling Smørgrav } 739111ccd25SDag-Erling Smørgrav krbret = krb5_change_password(pam_context, &creds, passdup, 74039384277SMark Murray &result_code, &result_code_string, &result_string); 741111ccd25SDag-Erling Smørgrav free(passdup); 74239384277SMark Murray if (krbret != 0) { 74339384277SMark Murray PAM_LOG("Error krb5_change_password(): %s", 74488c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 74539384277SMark Murray retval = PAM_AUTHTOK_ERR; 74639384277SMark Murray goto cleanup; 74739384277SMark Murray } 74839384277SMark Murray if (result_code) { 74939384277SMark Murray PAM_LOG("Error krb5_change_password(): (result_code)"); 75039384277SMark Murray retval = PAM_AUTHTOK_ERR; 75139384277SMark Murray goto cleanup; 75239384277SMark Murray } 75339384277SMark Murray 75439384277SMark Murray PAM_LOG("Password changed"); 75539384277SMark Murray 75639384277SMark Murray if (result_string.data) 75739384277SMark Murray free(result_string.data); 75839384277SMark Murray if (result_code_string.data) 75939384277SMark Murray free(result_code_string.data); 76039384277SMark Murray 76139384277SMark Murray cleanup: 76239384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 76339384277SMark Murray PAM_LOG("Done cleanup"); 76439384277SMark Murray cleanup2: 76539384277SMark Murray krb5_free_principal(pam_context, princ); 76639384277SMark Murray PAM_LOG("Done cleanup2"); 76739384277SMark Murray cleanup3: 76839384277SMark Murray if (princ_name) 76939384277SMark Murray free(princ_name); 77039384277SMark Murray 77139384277SMark Murray krb5_free_context(pam_context); 77239384277SMark Murray 77339384277SMark Murray PAM_LOG("Done cleanup3"); 77439384277SMark Murray 77524fe7ba0SDag-Erling Smørgrav return (retval); 77639384277SMark Murray } 77739384277SMark Murray 77839384277SMark Murray PAM_MODULE_ENTRY("pam_krb5"); 77939384277SMark Murray 78039384277SMark Murray /* 78139384277SMark Murray * This routine with some modification is from the MIT V5B6 appl/bsd/login.c 78239384277SMark Murray * Modified by Sam Hartman <hartmans@mit.edu> to support PAM services 78339384277SMark Murray * for Debian. 78439384277SMark Murray * 78539384277SMark Murray * Verify the Kerberos ticket-granting ticket just retrieved for the 78639384277SMark Murray * user. If the Kerberos server doesn't respond, assume the user is 78739384277SMark Murray * trying to fake us out (since we DID just get a TGT from what is 78839384277SMark Murray * supposedly our KDC). If the host/<host> service is unknown (i.e., 78939384277SMark Murray * the local keytab doesn't have it), and we cannot find another 79039384277SMark Murray * service we do have, let her in. 79139384277SMark Murray * 79239384277SMark Murray * Returns 1 for confirmation, -1 for failure, 0 for uncertainty. 79339384277SMark Murray */ 794b4240e6cSMark Murray /* ARGSUSED */ 79539384277SMark Murray static int 79639384277SMark Murray verify_krb_v5_tgt(krb5_context context, krb5_ccache ccache, 79739384277SMark Murray char *pam_service, int debug) 79839384277SMark Murray { 79939384277SMark Murray krb5_error_code retval; 80039384277SMark Murray krb5_principal princ; 80139384277SMark Murray krb5_keyblock *keyblock; 80239384277SMark Murray krb5_data packet; 80339384277SMark Murray krb5_auth_context auth_context; 804c2065008SMark Murray char phost[BUFSIZ]; 805c2065008SMark Murray const char *services[3], **service; 80639384277SMark Murray 80739384277SMark Murray packet.data = 0; 80839384277SMark Murray 80939384277SMark Murray /* If possible we want to try and verify the ticket we have 81039384277SMark Murray * received against a keytab. We will try multiple service 81139384277SMark Murray * principals, including at least the host principal and the PAM 81239384277SMark Murray * service principal. The host principal is preferred because access 81339384277SMark Murray * to that key is generally sufficient to compromise root, while the 81439384277SMark Murray * service key for this PAM service may be less carefully guarded. 81539384277SMark Murray * It is important to check the keytab first before the KDC so we do 81639384277SMark Murray * not get spoofed by a fake KDC. 81739384277SMark Murray */ 81839384277SMark Murray services[0] = "host"; 81939384277SMark Murray services[1] = pam_service; 82039384277SMark Murray services[2] = NULL; 82139384277SMark Murray keyblock = 0; 82239384277SMark Murray retval = -1; 82339384277SMark Murray for (service = &services[0]; *service != NULL; service++) { 82439384277SMark Murray retval = krb5_sname_to_principal(context, NULL, *service, 82539384277SMark Murray KRB5_NT_SRV_HST, &princ); 82639384277SMark Murray if (retval != 0) { 82739384277SMark Murray if (debug) 82888c8bcceSJacques Vidrine syslog(LOG_DEBUG, 82988c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 83088c8bcceSJacques Vidrine "krb5_sname_to_principal()", 83188c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 83239384277SMark Murray return -1; 83339384277SMark Murray } 83439384277SMark Murray 83539384277SMark Murray /* Extract the name directly. */ 83639384277SMark Murray strncpy(phost, compat_princ_component(context, princ, 1), 83739384277SMark Murray BUFSIZ); 83839384277SMark Murray phost[BUFSIZ - 1] = '\0'; 83939384277SMark Murray 84039384277SMark Murray /* 84139384277SMark Murray * Do we have service/<host> keys? 84239384277SMark Murray * (use default/configured keytab, kvno IGNORE_VNO to get the 84339384277SMark Murray * first match, and ignore enctype.) 84439384277SMark Murray */ 84539384277SMark Murray retval = krb5_kt_read_service_key(context, NULL, princ, 0, 0, 84639384277SMark Murray &keyblock); 84739384277SMark Murray if (retval != 0) 84839384277SMark Murray continue; 84939384277SMark Murray break; 85039384277SMark Murray } 85139384277SMark Murray if (retval != 0) { /* failed to find key */ 85239384277SMark Murray /* Keytab or service key does not exist */ 85339384277SMark Murray if (debug) 85488c8bcceSJacques Vidrine syslog(LOG_DEBUG, 85588c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 85688c8bcceSJacques Vidrine "krb5_kt_read_service_key()", 85788c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 85839384277SMark Murray retval = 0; 85939384277SMark Murray goto cleanup; 86039384277SMark Murray } 86139384277SMark Murray if (keyblock) 86239384277SMark Murray krb5_free_keyblock(context, keyblock); 86339384277SMark Murray 86439384277SMark Murray /* Talk to the kdc and construct the ticket. */ 86539384277SMark Murray auth_context = NULL; 86639384277SMark Murray retval = krb5_mk_req(context, &auth_context, 0, *service, phost, 86739384277SMark Murray NULL, ccache, &packet); 86839384277SMark Murray if (auth_context) { 86939384277SMark Murray krb5_auth_con_free(context, auth_context); 87039384277SMark Murray auth_context = NULL; /* setup for rd_req */ 87139384277SMark Murray } 87239384277SMark Murray if (retval) { 87339384277SMark Murray if (debug) 87488c8bcceSJacques Vidrine syslog(LOG_DEBUG, 87588c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 87688c8bcceSJacques Vidrine "krb5_mk_req()", 87788c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 87839384277SMark Murray retval = -1; 87939384277SMark Murray goto cleanup; 88039384277SMark Murray } 88139384277SMark Murray 88239384277SMark Murray /* Try to use the ticket. */ 88339384277SMark Murray retval = krb5_rd_req(context, &auth_context, &packet, princ, NULL, 88439384277SMark Murray NULL, NULL); 88539384277SMark Murray if (retval) { 88639384277SMark Murray if (debug) 88788c8bcceSJacques Vidrine syslog(LOG_DEBUG, 88888c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 88988c8bcceSJacques Vidrine "krb5_rd_req()", 89088c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 89139384277SMark Murray retval = -1; 89239384277SMark Murray } 89339384277SMark Murray else 89439384277SMark Murray retval = 1; 89539384277SMark Murray 89639384277SMark Murray cleanup: 89739384277SMark Murray if (packet.data) 89839384277SMark Murray compat_free_data_contents(context, &packet); 89939384277SMark Murray krb5_free_principal(context, princ); 90039384277SMark Murray return retval; 90139384277SMark Murray } 90239384277SMark Murray 90339384277SMark Murray /* Free the memory for cache_name. Called by pam_end() */ 904b4240e6cSMark Murray /* ARGSUSED */ 90539384277SMark Murray static void 906c2065008SMark Murray cleanup_cache(pam_handle_t *pamh __unused, void *data, int pam_end_status __unused) 90739384277SMark Murray { 90839384277SMark Murray krb5_context pam_context; 90939384277SMark Murray krb5_ccache ccache; 9107c2274dcSJacques Vidrine krb5_error_code krbret; 91139384277SMark Murray 91239384277SMark Murray if (krb5_init_context(&pam_context)) 91339384277SMark Murray return; 91439384277SMark Murray 9157c2274dcSJacques Vidrine krbret = krb5_cc_resolve(pam_context, data, &ccache); 9167c2274dcSJacques Vidrine if (krbret == 0) 91739384277SMark Murray krb5_cc_destroy(pam_context, ccache); 91839384277SMark Murray krb5_free_context(pam_context); 9197c2274dcSJacques Vidrine free(data); 92039384277SMark Murray } 92139384277SMark Murray 92239384277SMark Murray #ifdef COMPAT_HEIMDAL 92339384277SMark Murray #ifdef COMPAT_MIT 92439384277SMark Murray #error This cannot be MIT and Heimdal compatible! 92539384277SMark Murray #endif 92639384277SMark Murray #endif 92739384277SMark Murray 92839384277SMark Murray #ifndef COMPAT_HEIMDAL 92939384277SMark Murray #ifndef COMPAT_MIT 93039384277SMark Murray #error One of COMPAT_MIT and COMPAT_HEIMDAL must be specified! 93139384277SMark Murray #endif 93239384277SMark Murray #endif 93339384277SMark Murray 93439384277SMark Murray #ifdef COMPAT_HEIMDAL 935b4240e6cSMark Murray /* ARGSUSED */ 93639384277SMark Murray static const char * 937c2065008SMark Murray compat_princ_component(krb5_context context __unused, krb5_principal princ, int n) 93839384277SMark Murray { 93939384277SMark Murray return princ->name.name_string.val[n]; 94039384277SMark Murray } 94139384277SMark Murray 942b4240e6cSMark Murray /* ARGSUSED */ 94339384277SMark Murray static void 944c2065008SMark Murray compat_free_data_contents(krb5_context context __unused, krb5_data * data) 94539384277SMark Murray { 94639384277SMark Murray krb5_xfree(data->data); 94739384277SMark Murray } 94839384277SMark Murray #endif 94939384277SMark Murray 95039384277SMark Murray #ifdef COMPAT_MIT 95139384277SMark Murray static const char * 95239384277SMark Murray compat_princ_component(krb5_context context, krb5_principal princ, int n) 95339384277SMark Murray { 95439384277SMark Murray return krb5_princ_component(context, princ, n)->data; 95539384277SMark Murray } 95639384277SMark Murray 95739384277SMark Murray static void 95839384277SMark Murray compat_free_data_contents(krb5_context context, krb5_data * data) 95939384277SMark Murray { 96039384277SMark Murray krb5_free_data_contents(context, data); 96139384277SMark Murray } 96239384277SMark Murray #endif 963