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. 9e0bc7412SJacques Vidrine * Copyright (c) Networks Associates Technology, Inc., 2002. 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> 7439384277SMark Murray 7539384277SMark Murray #define COMPAT_HEIMDAL 7639384277SMark Murray /* #define COMPAT_MIT */ 7739384277SMark Murray 7839384277SMark Murray static int verify_krb_v5_tgt(krb5_context, krb5_ccache, char *, int); 7939384277SMark Murray static void cleanup_cache(pam_handle_t *, void *, int); 8039384277SMark Murray static const char *compat_princ_component(krb5_context, krb5_principal, int); 8139384277SMark Murray static void compat_free_data_contents(krb5_context, krb5_data *); 8239384277SMark Murray 8339384277SMark Murray #define USER_PROMPT "Username: " 8439384277SMark Murray #define PASSWORD_PROMPT "Password:" 8539384277SMark Murray #define NEW_PASSWORD_PROMPT "New Password:" 8639384277SMark Murray 8724fe7ba0SDag-Erling Smørgrav enum { 8824fe7ba0SDag-Erling Smørgrav PAM_OPT_AUTH_AS_SELF = PAM_OPT_STD_MAX, 8924fe7ba0SDag-Erling Smørgrav PAM_OPT_CCACHE, 9024fe7ba0SDag-Erling Smørgrav PAM_OPT_FORWARDABLE, 9124fe7ba0SDag-Erling Smørgrav PAM_OPT_NO_CCACHE, 9224fe7ba0SDag-Erling Smørgrav PAM_OPT_REUSE_CCACHE 9324fe7ba0SDag-Erling Smørgrav }; 9439384277SMark Murray 9539384277SMark Murray static struct opttab other_options[] = { 9639384277SMark Murray { "auth_as_self", PAM_OPT_AUTH_AS_SELF }, 9739384277SMark Murray { "ccache", PAM_OPT_CCACHE }, 9839384277SMark Murray { "forwardable", PAM_OPT_FORWARDABLE }, 9939384277SMark Murray { "no_ccache", PAM_OPT_NO_CCACHE }, 10039384277SMark Murray { "reuse_ccache", PAM_OPT_REUSE_CCACHE }, 10139384277SMark Murray { NULL, 0 } 10239384277SMark Murray }; 10339384277SMark Murray 10439384277SMark Murray /* 10539384277SMark Murray * authentication management 10639384277SMark Murray */ 10739384277SMark Murray PAM_EXTERN int 10824fe7ba0SDag-Erling Smørgrav pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 10924fe7ba0SDag-Erling Smørgrav int argc, const char *argv[]) 11039384277SMark Murray { 11139384277SMark Murray krb5_error_code krbret; 11239384277SMark Murray krb5_context pam_context; 11339384277SMark Murray krb5_creds creds; 11439384277SMark Murray krb5_principal princ; 1157c2274dcSJacques Vidrine krb5_ccache ccache; 11639384277SMark Murray krb5_get_init_creds_opt opts; 11739384277SMark Murray struct options options; 11839384277SMark Murray struct passwd *pwd; 11939384277SMark Murray int retval; 120c2065008SMark Murray const char *sourceuser, *user, *pass, *service; 1217c2274dcSJacques Vidrine char *principal, *princ_name, *ccache_name, luser[32], *srvdup; 12239384277SMark Murray 12339384277SMark Murray pam_std_option(&options, other_options, argc, argv); 12439384277SMark Murray 12539384277SMark Murray PAM_LOG("Options processed"); 12639384277SMark Murray 12739384277SMark Murray retval = pam_get_user(pamh, &user, USER_PROMPT); 12839384277SMark Murray if (retval != PAM_SUCCESS) 12924fe7ba0SDag-Erling Smørgrav return (retval); 13039384277SMark Murray 13139384277SMark Murray PAM_LOG("Got user: %s", user); 13239384277SMark Murray 13339384277SMark Murray retval = pam_get_item(pamh, PAM_RUSER, (const void **)&sourceuser); 13439384277SMark Murray if (retval != PAM_SUCCESS) 13524fe7ba0SDag-Erling Smørgrav return (retval); 13639384277SMark Murray 13739384277SMark Murray PAM_LOG("Got ruser: %s", sourceuser); 13839384277SMark Murray 13939384277SMark Murray service = NULL; 14039384277SMark Murray pam_get_item(pamh, PAM_SERVICE, (const void **)&service); 14139384277SMark Murray if (service == NULL) 14239384277SMark Murray service = "unknown"; 14339384277SMark Murray 14439384277SMark Murray PAM_LOG("Got service: %s", service); 14539384277SMark Murray 14639384277SMark Murray krbret = krb5_init_context(&pam_context); 14739384277SMark Murray if (krbret != 0) { 14839384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 14924fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 15039384277SMark Murray } 15139384277SMark Murray 15239384277SMark Murray PAM_LOG("Context initialised"); 15339384277SMark Murray 15439384277SMark Murray krb5_get_init_creds_opt_init(&opts); 15539384277SMark Murray 15639384277SMark Murray if (pam_test_option(&options, PAM_OPT_FORWARDABLE, NULL)) 15739384277SMark Murray krb5_get_init_creds_opt_set_forwardable(&opts, 1); 15839384277SMark Murray 15939384277SMark Murray PAM_LOG("Credentials initialised"); 16039384277SMark Murray 16139384277SMark Murray krbret = krb5_cc_register(pam_context, &krb5_mcc_ops, FALSE); 16239384277SMark Murray if (krbret != 0 && krbret != KRB5_CC_TYPE_EXISTS) { 16339384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 16439384277SMark Murray retval = PAM_SERVICE_ERR; 16539384277SMark Murray goto cleanup3; 16639384277SMark Murray } 16739384277SMark Murray 16839384277SMark Murray PAM_LOG("Done krb5_cc_register()"); 16939384277SMark Murray 17039384277SMark Murray /* Get principal name */ 17139384277SMark Murray if (pam_test_option(&options, PAM_OPT_AUTH_AS_SELF, NULL)) 17239384277SMark Murray asprintf(&principal, "%s/%s", sourceuser, user); 17339384277SMark Murray else 17439384277SMark Murray principal = strdup(user); 17539384277SMark Murray 17639384277SMark Murray PAM_LOG("Created principal: %s", principal); 17739384277SMark Murray 17839384277SMark Murray krbret = krb5_parse_name(pam_context, principal, &princ); 17939384277SMark Murray free(principal); 18039384277SMark Murray if (krbret != 0) { 18188c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 18288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 18339384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 18439384277SMark Murray retval = PAM_SERVICE_ERR; 18539384277SMark Murray goto cleanup3; 18639384277SMark Murray } 18739384277SMark Murray 18839384277SMark Murray PAM_LOG("Done krb5_parse_name()"); 18939384277SMark Murray 19039384277SMark Murray /* Now convert the principal name into something human readable */ 19139384277SMark Murray princ_name = NULL; 19239384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 19339384277SMark Murray if (krbret != 0) { 19488c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 19588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 19639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 19739384277SMark Murray retval = PAM_SERVICE_ERR; 19839384277SMark Murray goto cleanup2; 19939384277SMark Murray } 20039384277SMark Murray 20139384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 20239384277SMark Murray 20339384277SMark Murray /* Get password */ 204111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 20539384277SMark Murray if (retval != PAM_SUCCESS) 20639384277SMark Murray goto cleanup2; 20739384277SMark Murray 20839384277SMark Murray PAM_LOG("Got password"); 20939384277SMark Murray 21039384277SMark Murray /* Verify the local user exists (AFTER getting the password) */ 21139384277SMark Murray if (strchr(user, '@')) { 21239384277SMark Murray /* get a local account name for this principal */ 21339384277SMark Murray krbret = krb5_aname_to_localname(pam_context, princ, 21439384277SMark Murray sizeof(luser), luser); 21539384277SMark Murray if (krbret != 0) { 21639384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 21739384277SMark Murray PAM_LOG("Error krb5_aname_to_localname(): %s", 21888c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 21939384277SMark Murray retval = PAM_USER_UNKNOWN; 22039384277SMark Murray goto cleanup2; 22139384277SMark Murray } 22239384277SMark Murray 22339384277SMark Murray retval = pam_set_item(pamh, PAM_USER, luser); 22439384277SMark Murray if (retval != PAM_SUCCESS) 22539384277SMark Murray goto cleanup2; 22639384277SMark Murray 22739384277SMark Murray retval = pam_get_item(pamh, PAM_USER, (const void **)&user); 22839384277SMark Murray if (retval != PAM_SUCCESS) 22939384277SMark Murray goto cleanup2; 23039384277SMark Murray 23139384277SMark Murray PAM_LOG("PAM_USER Redone"); 23239384277SMark Murray } 23339384277SMark Murray 23439384277SMark Murray pwd = getpwnam(user); 23539384277SMark Murray if (pwd == NULL) { 23639384277SMark Murray retval = PAM_USER_UNKNOWN; 23739384277SMark Murray goto cleanup2; 23839384277SMark Murray } 23939384277SMark Murray 24039384277SMark Murray PAM_LOG("Done getpwnam()"); 24139384277SMark Murray 24239384277SMark Murray /* Get a TGT */ 24339384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 24439384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 24539384277SMark Murray pass, NULL, pamh, 0, NULL, &opts); 24639384277SMark Murray if (krbret != 0) { 24739384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 24839384277SMark Murray PAM_LOG("Error krb5_get_init_creds_password(): %s", 24988c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 25039384277SMark Murray retval = PAM_AUTH_ERR; 25139384277SMark Murray goto cleanup2; 25239384277SMark Murray } 25339384277SMark Murray 25439384277SMark Murray PAM_LOG("Got TGT"); 25539384277SMark Murray 2567c2274dcSJacques Vidrine /* Generate a temporary cache */ 2577c2274dcSJacques Vidrine krbret = krb5_cc_gen_new(pam_context, &krb5_mcc_ops, &ccache); 25839384277SMark Murray if (krbret != 0) { 25939384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 2607c2274dcSJacques Vidrine PAM_LOG("Error krb5_cc_gen_new(): %s", 26188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 26239384277SMark Murray retval = PAM_SERVICE_ERR; 26339384277SMark Murray goto cleanup; 26439384277SMark Murray } 26539384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache, princ); 26639384277SMark Murray if (krbret != 0) { 26739384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 26888c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 26988c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 27039384277SMark Murray retval = PAM_SERVICE_ERR; 27139384277SMark Murray goto cleanup; 27239384277SMark Murray } 27339384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache, &creds); 27439384277SMark Murray if (krbret != 0) { 27539384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 27688c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_store_cred(): %s", 27788c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 27839384277SMark Murray krb5_cc_destroy(pam_context, ccache); 27939384277SMark Murray retval = PAM_SERVICE_ERR; 28039384277SMark Murray goto cleanup; 28139384277SMark Murray } 28239384277SMark Murray 28339384277SMark Murray PAM_LOG("Credentials stashed"); 28439384277SMark Murray 28539384277SMark Murray /* Verify them */ 286111ccd25SDag-Erling Smørgrav if ((srvdup = strdup(service)) == NULL) { 287111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 288111ccd25SDag-Erling Smørgrav goto cleanup; 289111ccd25SDag-Erling Smørgrav } 290111ccd25SDag-Erling Smørgrav krbret = verify_krb_v5_tgt(pam_context, ccache, srvdup, 291111ccd25SDag-Erling Smørgrav pam_test_option(&options, PAM_OPT_FORWARDABLE, NULL)); 292111ccd25SDag-Erling Smørgrav free(srvdup); 293111ccd25SDag-Erling Smørgrav if (krbret == -1) { 29439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 29539384277SMark Murray krb5_cc_destroy(pam_context, ccache); 29639384277SMark Murray retval = PAM_AUTH_ERR; 29739384277SMark Murray goto cleanup; 29839384277SMark Murray } 29939384277SMark Murray 30039384277SMark Murray PAM_LOG("Credentials stash verified"); 30139384277SMark Murray 3027c2274dcSJacques Vidrine retval = pam_get_data(pamh, "ccache", (const void **)&ccache_name); 30339384277SMark Murray if (retval == PAM_SUCCESS) { 30439384277SMark Murray krb5_cc_destroy(pam_context, ccache); 30539384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 30639384277SMark Murray retval = PAM_AUTH_ERR; 30739384277SMark Murray goto cleanup; 30839384277SMark Murray } 30939384277SMark Murray 31039384277SMark Murray PAM_LOG("Credentials stash not pre-existing"); 31139384277SMark Murray 3127c2274dcSJacques Vidrine asprintf(&ccache_name, "%s:%s", krb5_cc_get_type(pam_context, 3137c2274dcSJacques Vidrine ccache), krb5_cc_get_name(pam_context, ccache)); 3147c2274dcSJacques Vidrine if (ccache_name == NULL) { 3157c2274dcSJacques Vidrine PAM_VERBOSE_ERROR("Kerberos 5 error"); 3167c2274dcSJacques Vidrine retval = PAM_BUF_ERR; 3177c2274dcSJacques Vidrine goto cleanup; 3187c2274dcSJacques Vidrine } 3197c2274dcSJacques Vidrine retval = pam_set_data(pamh, "ccache", ccache_name, cleanup_cache); 32039384277SMark Murray if (retval != 0) { 32139384277SMark Murray krb5_cc_destroy(pam_context, ccache); 32239384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 error"); 32339384277SMark Murray retval = PAM_SERVICE_ERR; 32439384277SMark Murray goto cleanup; 32539384277SMark Murray } 32639384277SMark Murray 32739384277SMark Murray PAM_LOG("Credentials stash saved"); 32839384277SMark Murray 32939384277SMark Murray cleanup: 33039384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 33139384277SMark Murray PAM_LOG("Done cleanup"); 33239384277SMark Murray cleanup2: 33339384277SMark Murray krb5_free_principal(pam_context, princ); 33439384277SMark Murray PAM_LOG("Done cleanup2"); 33539384277SMark Murray cleanup3: 33639384277SMark Murray if (princ_name) 33739384277SMark Murray free(princ_name); 33839384277SMark Murray 33939384277SMark Murray krb5_free_context(pam_context); 34039384277SMark Murray 34139384277SMark Murray PAM_LOG("Done cleanup3"); 34239384277SMark Murray 34339384277SMark Murray if (retval != PAM_SUCCESS) 34439384277SMark Murray PAM_VERBOSE_ERROR("Kerberos 5 refuses you"); 34539384277SMark Murray 34624fe7ba0SDag-Erling Smørgrav return (retval); 34739384277SMark Murray } 34839384277SMark Murray 34939384277SMark Murray PAM_EXTERN int 35024fe7ba0SDag-Erling Smørgrav pam_sm_setcred(pam_handle_t *pamh, int flags, 35124fe7ba0SDag-Erling Smørgrav int argc, const char *argv[]) 35239384277SMark Murray { 35339384277SMark Murray 35439384277SMark Murray krb5_error_code krbret; 35539384277SMark Murray krb5_context pam_context; 35639384277SMark Murray krb5_principal princ; 35739384277SMark Murray krb5_creds creds; 35839384277SMark Murray krb5_ccache ccache_temp, ccache_perm; 35939384277SMark Murray krb5_cc_cursor cursor; 36039384277SMark Murray struct options options; 36139384277SMark Murray struct passwd *pwd = NULL; 36239384277SMark Murray int retval; 36339384277SMark Murray char *user; 36439384277SMark Murray char *cache_name, *cache_env_name, *p, *q; 36539384277SMark Murray 36639384277SMark Murray uid_t euid; 36739384277SMark Murray gid_t egid; 36839384277SMark Murray 36939384277SMark Murray pam_std_option(&options, other_options, argc, argv); 37039384277SMark Murray 37139384277SMark Murray PAM_LOG("Options processed"); 37239384277SMark Murray 37339384277SMark Murray if (flags & PAM_DELETE_CRED) 37424fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 37539384277SMark Murray 37639384277SMark Murray if (flags & PAM_REFRESH_CRED) 37724fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 37839384277SMark Murray 37939384277SMark Murray if (flags & PAM_REINITIALIZE_CRED) 38024fe7ba0SDag-Erling Smørgrav return (PAM_SUCCESS); 38139384277SMark Murray 38239384277SMark Murray if (!(flags & PAM_ESTABLISH_CRED)) 38324fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 38439384277SMark Murray 38539384277SMark Murray PAM_LOG("Establishing credentials"); 38639384277SMark Murray 38739384277SMark Murray /* Get username */ 38839384277SMark Murray retval = pam_get_item(pamh, PAM_USER, (const void **)&user); 38939384277SMark Murray if (retval != PAM_SUCCESS) 39024fe7ba0SDag-Erling Smørgrav return (retval); 39139384277SMark Murray 39239384277SMark Murray PAM_LOG("Got user: %s", user); 39339384277SMark Murray 39439384277SMark Murray krbret = krb5_init_context(&pam_context); 39539384277SMark Murray if (krbret != 0) { 39688c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 39724fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 39839384277SMark Murray } 39939384277SMark Murray 40039384277SMark Murray PAM_LOG("Context initialised"); 40139384277SMark Murray 40239384277SMark Murray euid = geteuid(); /* Usually 0 */ 40339384277SMark Murray egid = getegid(); 40439384277SMark Murray 40539384277SMark Murray PAM_LOG("Got euid, egid: %d %d", euid, egid); 40639384277SMark Murray 4077c2274dcSJacques Vidrine /* Retrieve the temporary cache */ 4087c2274dcSJacques Vidrine retval = pam_get_data(pamh, "ccache", (const void **)&cache_name); 40939384277SMark Murray if (retval != PAM_SUCCESS) 41039384277SMark Murray goto cleanup3; 4117c2274dcSJacques Vidrine krbret = krb5_cc_resolve(pam_context, cache_name, &ccache_temp); 4127c2274dcSJacques Vidrine if (krbret != 0) { 4137c2274dcSJacques Vidrine PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", cache_name, 4147c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 4157c2274dcSJacques Vidrine goto cleanup3; 4167c2274dcSJacques Vidrine } 41739384277SMark Murray 41839384277SMark Murray /* Get the uid. This should exist. */ 41939384277SMark Murray pwd = getpwnam(user); 42039384277SMark Murray if (pwd == NULL) { 42139384277SMark Murray retval = PAM_USER_UNKNOWN; 42239384277SMark Murray goto cleanup3; 42339384277SMark Murray } 42439384277SMark Murray 42539384277SMark Murray PAM_LOG("Done getpwnam()"); 42639384277SMark Murray 42739384277SMark Murray /* Avoid following a symlink as root */ 42839384277SMark Murray if (setegid(pwd->pw_gid)) { 42939384277SMark Murray retval = PAM_SERVICE_ERR; 43039384277SMark Murray goto cleanup3; 43139384277SMark Murray } 43239384277SMark Murray if (seteuid(pwd->pw_uid)) { 43339384277SMark Murray retval = PAM_SERVICE_ERR; 43439384277SMark Murray goto cleanup3; 43539384277SMark Murray } 43639384277SMark Murray 43739384277SMark Murray PAM_LOG("Done setegid() & seteuid()"); 43839384277SMark Murray 43939384277SMark Murray /* Get the cache name */ 44039384277SMark Murray cache_name = NULL; 44139384277SMark Murray pam_test_option(&options, PAM_OPT_CCACHE, &cache_name); 44239384277SMark Murray if (cache_name == NULL) 44339384277SMark Murray asprintf(&cache_name, "FILE:/tmp/krb5cc_%d", pwd->pw_uid); 44439384277SMark Murray 44539384277SMark Murray p = calloc(PATH_MAX + 16, sizeof(char)); 44639384277SMark Murray q = cache_name; 44739384277SMark Murray 44839384277SMark Murray if (p == NULL) { 44939384277SMark Murray PAM_LOG("Error malloc(): failure"); 45039384277SMark Murray retval = PAM_BUF_ERR; 45139384277SMark Murray goto cleanup3; 45239384277SMark Murray } 45339384277SMark Murray cache_name = p; 45439384277SMark Murray 45539384277SMark Murray /* convert %u and %p */ 45639384277SMark Murray while (*q) { 45739384277SMark Murray if (*q == '%') { 45839384277SMark Murray q++; 45939384277SMark Murray if (*q == 'u') { 46039384277SMark Murray sprintf(p, "%d", pwd->pw_uid); 46139384277SMark Murray p += strlen(p); 46239384277SMark Murray } 46339384277SMark Murray else if (*q == 'p') { 46439384277SMark Murray sprintf(p, "%d", getpid()); 46539384277SMark Murray p += strlen(p); 46639384277SMark Murray } 46739384277SMark Murray else { 46839384277SMark Murray /* Not a special token */ 46939384277SMark Murray *p++ = '%'; 47039384277SMark Murray q--; 47139384277SMark Murray } 47239384277SMark Murray q++; 47339384277SMark Murray } 47439384277SMark Murray else { 47539384277SMark Murray *p++ = *q++; 47639384277SMark Murray } 47739384277SMark Murray } 47839384277SMark Murray 47939384277SMark Murray PAM_LOG("Got cache_name: %s", cache_name); 48039384277SMark Murray 48139384277SMark Murray /* Initialize the new ccache */ 48239384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache_temp, &princ); 48339384277SMark Murray if (krbret != 0) { 48439384277SMark Murray PAM_LOG("Error krb5_cc_get_principal(): %s", 48588c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 48639384277SMark Murray retval = PAM_SERVICE_ERR; 48739384277SMark Murray goto cleanup3; 48839384277SMark Murray } 48939384277SMark Murray krbret = krb5_cc_resolve(pam_context, cache_name, &ccache_perm); 49039384277SMark Murray if (krbret != 0) { 49188c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_resolve(): %s", 49288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 49339384277SMark Murray retval = PAM_SERVICE_ERR; 49439384277SMark Murray goto cleanup2; 49539384277SMark Murray } 49639384277SMark Murray krbret = krb5_cc_initialize(pam_context, ccache_perm, princ); 49739384277SMark Murray if (krbret != 0) { 49888c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_initialize(): %s", 49988c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 50039384277SMark Murray retval = PAM_SERVICE_ERR; 50139384277SMark Murray goto cleanup2; 50239384277SMark Murray } 50339384277SMark Murray 50439384277SMark Murray PAM_LOG("Cache initialised"); 50539384277SMark Murray 50639384277SMark Murray /* Prepare for iteration over creds */ 50739384277SMark Murray krbret = krb5_cc_start_seq_get(pam_context, ccache_temp, &cursor); 50839384277SMark Murray if (krbret != 0) { 50988c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_start_seq_get(): %s", 51088c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 51139384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 51239384277SMark Murray retval = PAM_SERVICE_ERR; 51339384277SMark Murray goto cleanup2; 51439384277SMark Murray } 51539384277SMark Murray 51639384277SMark Murray PAM_LOG("Prepared for iteration"); 51739384277SMark Murray 51839384277SMark Murray /* Copy the creds (should be two of them) */ 51939384277SMark Murray while ((krbret = krb5_cc_next_cred(pam_context, ccache_temp, 52039384277SMark Murray &cursor, &creds) == 0)) { 52139384277SMark Murray krbret = krb5_cc_store_cred(pam_context, ccache_perm, &creds); 52239384277SMark Murray if (krbret != 0) { 52339384277SMark Murray PAM_LOG("Error krb5_cc_store_cred(): %s", 52488c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 52539384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 52639384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 52739384277SMark Murray retval = PAM_SERVICE_ERR; 52839384277SMark Murray goto cleanup2; 52939384277SMark Murray } 53039384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 53139384277SMark Murray PAM_LOG("Iteration"); 53239384277SMark Murray } 53339384277SMark Murray krb5_cc_end_seq_get(pam_context, ccache_temp, &cursor); 53439384277SMark Murray 53539384277SMark Murray PAM_LOG("Done iterating"); 53639384277SMark Murray 53739384277SMark Murray if (strstr(cache_name, "FILE:") == cache_name) { 53839384277SMark Murray if (chown(&cache_name[5], pwd->pw_uid, pwd->pw_gid) == -1) { 53939384277SMark Murray PAM_LOG("Error chown(): %s", strerror(errno)); 54039384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 54139384277SMark Murray retval = PAM_SERVICE_ERR; 54239384277SMark Murray goto cleanup2; 54339384277SMark Murray } 54439384277SMark Murray PAM_LOG("Done chown()"); 54539384277SMark Murray 54639384277SMark Murray if (chmod(&cache_name[5], (S_IRUSR | S_IWUSR)) == -1) { 54739384277SMark Murray PAM_LOG("Error chmod(): %s", strerror(errno)); 54839384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 54939384277SMark Murray retval = PAM_SERVICE_ERR; 55039384277SMark Murray goto cleanup2; 55139384277SMark Murray } 55239384277SMark Murray PAM_LOG("Done chmod()"); 55339384277SMark Murray } 55439384277SMark Murray 55539384277SMark Murray krb5_cc_close(pam_context, ccache_perm); 55639384277SMark Murray 55739384277SMark Murray PAM_LOG("Cache closed"); 55839384277SMark Murray 55939384277SMark Murray cache_env_name = malloc(strlen(cache_name) + 12); 56039384277SMark Murray if (!cache_env_name) { 56139384277SMark Murray PAM_LOG("Error malloc(): failure"); 56239384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 56339384277SMark Murray retval = PAM_BUF_ERR; 56439384277SMark Murray goto cleanup2; 56539384277SMark Murray } 56639384277SMark Murray 56739384277SMark Murray sprintf(cache_env_name, "KRB5CCNAME=%s", cache_name); 56839384277SMark Murray if ((retval = pam_putenv(pamh, cache_env_name)) != 0) { 56939384277SMark Murray PAM_LOG("Error pam_putenv(): %s", pam_strerror(pamh, retval)); 57039384277SMark Murray krb5_cc_destroy(pam_context, ccache_perm); 57139384277SMark Murray retval = PAM_SERVICE_ERR; 57239384277SMark Murray goto cleanup2; 57339384277SMark Murray } 57439384277SMark Murray 57539384277SMark Murray PAM_LOG("Environment done: KRB5CCNAME=%s", cache_name); 57639384277SMark Murray 57739384277SMark Murray cleanup2: 57839384277SMark Murray krb5_free_principal(pam_context, princ); 57939384277SMark Murray PAM_LOG("Done cleanup2"); 58039384277SMark Murray cleanup3: 58139384277SMark Murray krb5_free_context(pam_context); 58239384277SMark Murray PAM_LOG("Done cleanup3"); 58339384277SMark Murray 58439384277SMark Murray seteuid(euid); 58539384277SMark Murray setegid(egid); 58639384277SMark Murray 58739384277SMark Murray PAM_LOG("Done seteuid() & setegid()"); 58839384277SMark Murray 58924fe7ba0SDag-Erling Smørgrav return (retval); 59039384277SMark Murray } 59139384277SMark Murray 59239384277SMark Murray /* 59339384277SMark Murray * account management 59439384277SMark Murray */ 59539384277SMark Murray PAM_EXTERN int 59624fe7ba0SDag-Erling Smørgrav pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused, 59724fe7ba0SDag-Erling Smørgrav int argc, const char *argv[]) 59839384277SMark Murray { 59939384277SMark Murray krb5_error_code krbret; 60039384277SMark Murray krb5_context pam_context; 60139384277SMark Murray krb5_ccache ccache; 60239384277SMark Murray krb5_principal princ; 60339384277SMark Murray struct options options; 60439384277SMark Murray int retval; 6057c2274dcSJacques Vidrine const char *user, *ccache_name; 60639384277SMark Murray 60739384277SMark Murray pam_std_option(&options, other_options, argc, argv); 60839384277SMark Murray 60939384277SMark Murray PAM_LOG("Options processed"); 61039384277SMark Murray 61139384277SMark Murray retval = pam_get_item(pamh, PAM_USER, (const void **)&user); 61239384277SMark Murray if (retval != PAM_SUCCESS) 61324fe7ba0SDag-Erling Smørgrav return (retval); 61439384277SMark Murray 61539384277SMark Murray PAM_LOG("Got user: %s", user); 61639384277SMark Murray 61739384277SMark Murray krbret = krb5_init_context(&pam_context); 61839384277SMark Murray if (krbret != 0) { 61988c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 62024fe7ba0SDag-Erling Smørgrav return (PAM_PERM_DENIED); 62139384277SMark Murray } 62239384277SMark Murray 62339384277SMark Murray PAM_LOG("Context initialised"); 62439384277SMark Murray 6257c2274dcSJacques Vidrine retval = pam_get_data(pamh, "ccache", (const void **)&ccache_name); 6267c2274dcSJacques Vidrine if (retval != PAM_SUCCESS) 6277c2274dcSJacques Vidrine return (PAM_SUCCESS); 6287c2274dcSJacques Vidrine krbret = krb5_cc_resolve(pam_context, ccache_name, &ccache); 6297c2274dcSJacques Vidrine if (krbret != 0) { 6307c2274dcSJacques Vidrine PAM_LOG("Error krb5_cc_resolve(\"%s\"): %s", ccache_name, 6317c2274dcSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 6327c2274dcSJacques Vidrine krb5_free_context(pam_context); 6337c2274dcSJacques Vidrine return (PAM_PERM_DENIED); 6347c2274dcSJacques Vidrine } 6357c2274dcSJacques Vidrine 6367c2274dcSJacques Vidrine PAM_LOG("Got ccache %s", ccache_name); 6377c2274dcSJacques Vidrine 6387c2274dcSJacques Vidrine 63939384277SMark Murray krbret = krb5_cc_get_principal(pam_context, ccache, &princ); 64039384277SMark Murray if (krbret != 0) { 64188c8bcceSJacques Vidrine PAM_LOG("Error krb5_cc_get_principal(): %s", 64288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 64339384277SMark Murray retval = PAM_PERM_DENIED;; 64439384277SMark Murray goto cleanup; 64539384277SMark Murray } 64639384277SMark Murray 64739384277SMark Murray PAM_LOG("Got principal"); 64839384277SMark Murray 64939384277SMark Murray if (krb5_kuserok(pam_context, princ, user)) 65039384277SMark Murray retval = PAM_SUCCESS; 65139384277SMark Murray else 65239384277SMark Murray retval = PAM_PERM_DENIED; 65339384277SMark Murray krb5_free_principal(pam_context, princ); 65439384277SMark Murray 65539384277SMark Murray PAM_LOG("Done kuserok()"); 65639384277SMark Murray 65739384277SMark Murray cleanup: 65839384277SMark Murray krb5_free_context(pam_context); 65939384277SMark Murray PAM_LOG("Done cleanup"); 66039384277SMark Murray 66124fe7ba0SDag-Erling Smørgrav return (retval); 66239384277SMark Murray 66339384277SMark Murray } 66439384277SMark Murray 66539384277SMark Murray /* 66639384277SMark Murray * password management 66739384277SMark Murray */ 66839384277SMark Murray PAM_EXTERN int 66924fe7ba0SDag-Erling Smørgrav pam_sm_chauthtok(pam_handle_t *pamh, int flags, 67024fe7ba0SDag-Erling Smørgrav int argc, const char *argv[]) 67139384277SMark Murray { 67239384277SMark Murray krb5_error_code krbret; 67339384277SMark Murray krb5_context pam_context; 67439384277SMark Murray krb5_creds creds; 67539384277SMark Murray krb5_principal princ; 67639384277SMark Murray krb5_get_init_creds_opt opts; 67739384277SMark Murray krb5_data result_code_string, result_string; 67839384277SMark Murray struct options options; 67939384277SMark Murray int result_code, retval; 680111ccd25SDag-Erling Smørgrav const char *user, *pass; 681111ccd25SDag-Erling Smørgrav char *princ_name, *passdup; 68239384277SMark Murray 68339384277SMark Murray pam_std_option(&options, other_options, argc, argv); 68439384277SMark Murray 68539384277SMark Murray PAM_LOG("Options processed"); 68639384277SMark Murray 68739384277SMark Murray if (!(flags & PAM_UPDATE_AUTHTOK)) 68824fe7ba0SDag-Erling Smørgrav return (PAM_AUTHTOK_ERR); 68939384277SMark Murray 69039384277SMark Murray retval = pam_get_item(pamh, PAM_USER, (const void **)&user); 69139384277SMark Murray if (retval != PAM_SUCCESS) 69224fe7ba0SDag-Erling Smørgrav return (retval); 69339384277SMark Murray 69439384277SMark Murray PAM_LOG("Got user: %s", user); 69539384277SMark Murray 69639384277SMark Murray krbret = krb5_init_context(&pam_context); 69739384277SMark Murray if (krbret != 0) { 69888c8bcceSJacques Vidrine PAM_LOG("Error krb5_init_context() failed"); 69924fe7ba0SDag-Erling Smørgrav return (PAM_SERVICE_ERR); 70039384277SMark Murray } 70139384277SMark Murray 70239384277SMark Murray PAM_LOG("Context initialised"); 70339384277SMark Murray 70439384277SMark Murray krb5_get_init_creds_opt_init(&opts); 70539384277SMark Murray 70639384277SMark Murray PAM_LOG("Credentials options initialised"); 70739384277SMark Murray 70839384277SMark Murray /* Get principal name */ 70939384277SMark Murray krbret = krb5_parse_name(pam_context, user, &princ); 71039384277SMark Murray if (krbret != 0) { 71188c8bcceSJacques Vidrine PAM_LOG("Error krb5_parse_name(): %s", 71288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 71339384277SMark Murray retval = PAM_USER_UNKNOWN; 71439384277SMark Murray goto cleanup3; 71539384277SMark Murray } 71639384277SMark Murray 71739384277SMark Murray /* Now convert the principal name into something human readable */ 71839384277SMark Murray princ_name = NULL; 71939384277SMark Murray krbret = krb5_unparse_name(pam_context, princ, &princ_name); 72039384277SMark Murray if (krbret != 0) { 72188c8bcceSJacques Vidrine PAM_LOG("Error krb5_unparse_name(): %s", 72288c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 72339384277SMark Murray retval = PAM_SERVICE_ERR; 72439384277SMark Murray goto cleanup2; 72539384277SMark Murray } 72639384277SMark Murray 72739384277SMark Murray PAM_LOG("Got principal: %s", princ_name); 72839384277SMark Murray 72939384277SMark Murray /* Get password */ 730111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, PAM_OLDAUTHTOK, &pass, PASSWORD_PROMPT); 73139384277SMark Murray if (retval != PAM_SUCCESS) 73239384277SMark Murray goto cleanup2; 73339384277SMark Murray 73439384277SMark Murray PAM_LOG("Got password"); 73539384277SMark Murray 73639384277SMark Murray memset(&creds, 0, sizeof(krb5_creds)); 73739384277SMark Murray krbret = krb5_get_init_creds_password(pam_context, &creds, princ, 73839384277SMark Murray pass, NULL, pamh, 0, "kadmin/changepw", &opts); 73939384277SMark Murray if (krbret != 0) { 74039384277SMark Murray PAM_LOG("Error krb5_get_init_creds_password()", 74188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 74239384277SMark Murray retval = PAM_AUTH_ERR; 74339384277SMark Murray goto cleanup2; 74439384277SMark Murray } 74539384277SMark Murray 74639384277SMark Murray PAM_LOG("Credentials established"); 74739384277SMark Murray 74839384277SMark Murray /* Now get the new password */ 749111ccd25SDag-Erling Smørgrav for (;;) { 750111ccd25SDag-Erling Smørgrav retval = pam_get_authtok(pamh, 751111ccd25SDag-Erling Smørgrav PAM_AUTHTOK, &pass, NEW_PASSWORD_PROMPT); 752111ccd25SDag-Erling Smørgrav if (retval != PAM_TRY_AGAIN) 753111ccd25SDag-Erling Smørgrav break; 754111ccd25SDag-Erling Smørgrav pam_error(pamh, "Mismatch; try again, EOF to quit."); 75539384277SMark Murray } 756111ccd25SDag-Erling Smørgrav if (retval != PAM_SUCCESS) 757111ccd25SDag-Erling Smørgrav goto cleanup; 75839384277SMark Murray 759111ccd25SDag-Erling Smørgrav PAM_LOG("Got new password"); 76039384277SMark Murray 76139384277SMark Murray /* Change it */ 762111ccd25SDag-Erling Smørgrav if ((passdup = strdup(pass)) == NULL) { 763111ccd25SDag-Erling Smørgrav retval = PAM_BUF_ERR; 764111ccd25SDag-Erling Smørgrav goto cleanup; 765111ccd25SDag-Erling Smørgrav } 766111ccd25SDag-Erling Smørgrav krbret = krb5_change_password(pam_context, &creds, passdup, 76739384277SMark Murray &result_code, &result_code_string, &result_string); 768111ccd25SDag-Erling Smørgrav free(passdup); 76939384277SMark Murray if (krbret != 0) { 77039384277SMark Murray PAM_LOG("Error krb5_change_password(): %s", 77188c8bcceSJacques Vidrine krb5_get_err_text(pam_context, krbret)); 77239384277SMark Murray retval = PAM_AUTHTOK_ERR; 77339384277SMark Murray goto cleanup; 77439384277SMark Murray } 77539384277SMark Murray if (result_code) { 77639384277SMark Murray PAM_LOG("Error krb5_change_password(): (result_code)"); 77739384277SMark Murray retval = PAM_AUTHTOK_ERR; 77839384277SMark Murray goto cleanup; 77939384277SMark Murray } 78039384277SMark Murray 78139384277SMark Murray PAM_LOG("Password changed"); 78239384277SMark Murray 78339384277SMark Murray if (result_string.data) 78439384277SMark Murray free(result_string.data); 78539384277SMark Murray if (result_code_string.data) 78639384277SMark Murray free(result_code_string.data); 78739384277SMark Murray 78839384277SMark Murray cleanup: 78939384277SMark Murray krb5_free_cred_contents(pam_context, &creds); 79039384277SMark Murray PAM_LOG("Done cleanup"); 79139384277SMark Murray cleanup2: 79239384277SMark Murray krb5_free_principal(pam_context, princ); 79339384277SMark Murray PAM_LOG("Done cleanup2"); 79439384277SMark Murray cleanup3: 79539384277SMark Murray if (princ_name) 79639384277SMark Murray free(princ_name); 79739384277SMark Murray 79839384277SMark Murray krb5_free_context(pam_context); 79939384277SMark Murray 80039384277SMark Murray PAM_LOG("Done cleanup3"); 80139384277SMark Murray 80224fe7ba0SDag-Erling Smørgrav return (retval); 80339384277SMark Murray } 80439384277SMark Murray 80539384277SMark Murray PAM_MODULE_ENTRY("pam_krb5"); 80639384277SMark Murray 80739384277SMark Murray /* 80839384277SMark Murray * This routine with some modification is from the MIT V5B6 appl/bsd/login.c 80939384277SMark Murray * Modified by Sam Hartman <hartmans@mit.edu> to support PAM services 81039384277SMark Murray * for Debian. 81139384277SMark Murray * 81239384277SMark Murray * Verify the Kerberos ticket-granting ticket just retrieved for the 81339384277SMark Murray * user. If the Kerberos server doesn't respond, assume the user is 81439384277SMark Murray * trying to fake us out (since we DID just get a TGT from what is 81539384277SMark Murray * supposedly our KDC). If the host/<host> service is unknown (i.e., 81639384277SMark Murray * the local keytab doesn't have it), and we cannot find another 81739384277SMark Murray * service we do have, let her in. 81839384277SMark Murray * 81939384277SMark Murray * Returns 1 for confirmation, -1 for failure, 0 for uncertainty. 82039384277SMark Murray */ 82139384277SMark Murray static int 82239384277SMark Murray verify_krb_v5_tgt(krb5_context context, krb5_ccache ccache, 82339384277SMark Murray char *pam_service, int debug) 82439384277SMark Murray { 82539384277SMark Murray krb5_error_code retval; 82639384277SMark Murray krb5_principal princ; 82739384277SMark Murray krb5_keyblock *keyblock; 82839384277SMark Murray krb5_data packet; 82939384277SMark Murray krb5_auth_context auth_context; 830c2065008SMark Murray char phost[BUFSIZ]; 831c2065008SMark Murray const char *services[3], **service; 83239384277SMark Murray 83339384277SMark Murray packet.data = 0; 83439384277SMark Murray 83539384277SMark Murray /* If possible we want to try and verify the ticket we have 83639384277SMark Murray * received against a keytab. We will try multiple service 83739384277SMark Murray * principals, including at least the host principal and the PAM 83839384277SMark Murray * service principal. The host principal is preferred because access 83939384277SMark Murray * to that key is generally sufficient to compromise root, while the 84039384277SMark Murray * service key for this PAM service may be less carefully guarded. 84139384277SMark Murray * It is important to check the keytab first before the KDC so we do 84239384277SMark Murray * not get spoofed by a fake KDC. 84339384277SMark Murray */ 84439384277SMark Murray services[0] = "host"; 84539384277SMark Murray services[1] = pam_service; 84639384277SMark Murray services[2] = NULL; 84739384277SMark Murray keyblock = 0; 84839384277SMark Murray retval = -1; 84939384277SMark Murray for (service = &services[0]; *service != NULL; service++) { 85039384277SMark Murray retval = krb5_sname_to_principal(context, NULL, *service, 85139384277SMark Murray KRB5_NT_SRV_HST, &princ); 85239384277SMark Murray if (retval != 0) { 85339384277SMark Murray if (debug) 85488c8bcceSJacques Vidrine syslog(LOG_DEBUG, 85588c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 85688c8bcceSJacques Vidrine "krb5_sname_to_principal()", 85788c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 85839384277SMark Murray return -1; 85939384277SMark Murray } 86039384277SMark Murray 86139384277SMark Murray /* Extract the name directly. */ 86239384277SMark Murray strncpy(phost, compat_princ_component(context, princ, 1), 86339384277SMark Murray BUFSIZ); 86439384277SMark Murray phost[BUFSIZ - 1] = '\0'; 86539384277SMark Murray 86639384277SMark Murray /* 86739384277SMark Murray * Do we have service/<host> keys? 86839384277SMark Murray * (use default/configured keytab, kvno IGNORE_VNO to get the 86939384277SMark Murray * first match, and ignore enctype.) 87039384277SMark Murray */ 87139384277SMark Murray retval = krb5_kt_read_service_key(context, NULL, princ, 0, 0, 87239384277SMark Murray &keyblock); 87339384277SMark Murray if (retval != 0) 87439384277SMark Murray continue; 87539384277SMark Murray break; 87639384277SMark Murray } 87739384277SMark Murray if (retval != 0) { /* failed to find key */ 87839384277SMark Murray /* Keytab or service key does not exist */ 87939384277SMark Murray if (debug) 88088c8bcceSJacques Vidrine syslog(LOG_DEBUG, 88188c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 88288c8bcceSJacques Vidrine "krb5_kt_read_service_key()", 88388c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 88439384277SMark Murray retval = 0; 88539384277SMark Murray goto cleanup; 88639384277SMark Murray } 88739384277SMark Murray if (keyblock) 88839384277SMark Murray krb5_free_keyblock(context, keyblock); 88939384277SMark Murray 89039384277SMark Murray /* Talk to the kdc and construct the ticket. */ 89139384277SMark Murray auth_context = NULL; 89239384277SMark Murray retval = krb5_mk_req(context, &auth_context, 0, *service, phost, 89339384277SMark Murray NULL, ccache, &packet); 89439384277SMark Murray if (auth_context) { 89539384277SMark Murray krb5_auth_con_free(context, auth_context); 89639384277SMark Murray auth_context = NULL; /* setup for rd_req */ 89739384277SMark Murray } 89839384277SMark Murray if (retval) { 89939384277SMark Murray if (debug) 90088c8bcceSJacques Vidrine syslog(LOG_DEBUG, 90188c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 90288c8bcceSJacques Vidrine "krb5_mk_req()", 90388c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 90439384277SMark Murray retval = -1; 90539384277SMark Murray goto cleanup; 90639384277SMark Murray } 90739384277SMark Murray 90839384277SMark Murray /* Try to use the ticket. */ 90939384277SMark Murray retval = krb5_rd_req(context, &auth_context, &packet, princ, NULL, 91039384277SMark Murray NULL, NULL); 91139384277SMark Murray if (retval) { 91239384277SMark Murray if (debug) 91388c8bcceSJacques Vidrine syslog(LOG_DEBUG, 91488c8bcceSJacques Vidrine "pam_krb5: verify_krb_v5_tgt(): %s: %s", 91588c8bcceSJacques Vidrine "krb5_rd_req()", 91688c8bcceSJacques Vidrine krb5_get_err_text(context, retval)); 91739384277SMark Murray retval = -1; 91839384277SMark Murray } 91939384277SMark Murray else 92039384277SMark Murray retval = 1; 92139384277SMark Murray 92239384277SMark Murray cleanup: 92339384277SMark Murray if (packet.data) 92439384277SMark Murray compat_free_data_contents(context, &packet); 92539384277SMark Murray krb5_free_principal(context, princ); 92639384277SMark Murray return retval; 92739384277SMark Murray } 92839384277SMark Murray 92939384277SMark Murray /* Free the memory for cache_name. Called by pam_end() */ 93039384277SMark Murray static void 931c2065008SMark Murray cleanup_cache(pam_handle_t *pamh __unused, void *data, int pam_end_status __unused) 93239384277SMark Murray { 93339384277SMark Murray krb5_context pam_context; 93439384277SMark Murray krb5_ccache ccache; 9357c2274dcSJacques Vidrine krb5_error_code krbret; 93639384277SMark Murray 93739384277SMark Murray if (krb5_init_context(&pam_context)) 93839384277SMark Murray return; 93939384277SMark Murray 9407c2274dcSJacques Vidrine krbret = krb5_cc_resolve(pam_context, data, &ccache); 9417c2274dcSJacques Vidrine if (krbret == 0) 94239384277SMark Murray krb5_cc_destroy(pam_context, ccache); 94339384277SMark Murray krb5_free_context(pam_context); 9447c2274dcSJacques Vidrine free(data); 94539384277SMark Murray } 94639384277SMark Murray 94739384277SMark Murray #ifdef COMPAT_HEIMDAL 94839384277SMark Murray #ifdef COMPAT_MIT 94939384277SMark Murray #error This cannot be MIT and Heimdal compatible! 95039384277SMark Murray #endif 95139384277SMark Murray #endif 95239384277SMark Murray 95339384277SMark Murray #ifndef COMPAT_HEIMDAL 95439384277SMark Murray #ifndef COMPAT_MIT 95539384277SMark Murray #error One of COMPAT_MIT and COMPAT_HEIMDAL must be specified! 95639384277SMark Murray #endif 95739384277SMark Murray #endif 95839384277SMark Murray 95939384277SMark Murray #ifdef COMPAT_HEIMDAL 96039384277SMark Murray static const char * 961c2065008SMark Murray compat_princ_component(krb5_context context __unused, krb5_principal princ, int n) 96239384277SMark Murray { 96339384277SMark Murray return princ->name.name_string.val[n]; 96439384277SMark Murray } 96539384277SMark Murray 96639384277SMark Murray static void 967c2065008SMark Murray compat_free_data_contents(krb5_context context __unused, krb5_data * data) 96839384277SMark Murray { 96939384277SMark Murray krb5_xfree(data->data); 97039384277SMark Murray } 97139384277SMark Murray #endif 97239384277SMark Murray 97339384277SMark Murray #ifdef COMPAT_MIT 97439384277SMark Murray static const char * 97539384277SMark Murray compat_princ_component(krb5_context context, krb5_principal princ, int n) 97639384277SMark Murray { 97739384277SMark Murray return krb5_princ_component(context, princ, n)->data; 97839384277SMark Murray } 97939384277SMark Murray 98039384277SMark Murray static void 98139384277SMark Murray compat_free_data_contents(krb5_context context, krb5_data * data) 98239384277SMark Murray { 98339384277SMark Murray krb5_free_data_contents(context, data); 98439384277SMark Murray } 98539384277SMark Murray #endif 986