1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright 2000 James Bloom 5 * All rights reserved. 6 * Based upon code Copyright 1998 Juniper Networks, Inc. 7 * Copyright (c) 2001-2003 Networks Associates Technology, Inc. 8 * All rights reserved. 9 * 10 * Portions of this software were developed for the FreeBSD Project by 11 * ThinkSec AS and NAI Labs, the Security Research Division of Network 12 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 13 * ("CBOSS"), as part of the DARPA CHATS research program. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. The name of the author may not be used to endorse or promote 24 * products derived from this software without specific prior written 25 * permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40#include <sys/cdefs.h> 41__FBSDID("$FreeBSD$"); 42 43#include <sys/types.h> 44#include <opie.h> 45#include <pwd.h> 46#include <stdio.h> 47#include <stdlib.h> 48#include <string.h> 49#include <unistd.h> 50 51#define PAM_SM_AUTH 52 53#include <security/pam_appl.h> 54#include <security/pam_modules.h> 55#include <security/pam_mod_misc.h> 56 57#define PAM_OPT_NO_FAKE_PROMPTS "no_fake_prompts" 58 59PAM_EXTERN int 60pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 61 int argc __unused, const char *argv[] __unused) 62{ 63 struct opie opie; 64 struct passwd *pwd; 65 int retval, i; 66 const char *(promptstr[]) = { "%s\nPassword: ", "%s\nPassword [echo on]: "}; 67 char challenge[OPIE_CHALLENGE_MAX + 1]; 68 char principal[OPIE_PRINCIPAL_MAX]; 69 const char *user; 70 char *response; 71 int style; 72 73 user = NULL; 74 if (openpam_get_option(pamh, PAM_OPT_AUTH_AS_SELF)) { 75 if ((pwd = getpwnam(getlogin())) == NULL) 76 return (PAM_AUTH_ERR); 77 user = pwd->pw_name; 78 } 79 else { 80 retval = pam_get_user(pamh, &user, NULL); 81 if (retval != PAM_SUCCESS) 82 return (retval); 83 } 84 85 PAM_LOG("Got user: %s", user); 86 87 /* 88 * Watch out: libopie feels entitled to truncate the user name 89 * passed to it if it's longer than OPIE_PRINCIPAL_MAX, which is 90 * not uncommon in Windows environments. 91 */ 92 if (strlen(user) >= sizeof(principal)) 93 return (PAM_AUTH_ERR); 94 strlcpy(principal, user, sizeof(principal)); 95 96 /* 97 * Don't call the OPIE atexit() handler when our program exits, 98 * since the module has been unloaded and we will SEGV. 99 */ 100 opiedisableaeh(); 101 102 /* 103 * If the no_fake_prompts option was given, and the user 104 * doesn't have an OPIE key, just fail rather than present the 105 * user with a bogus OPIE challenge. 106 */ 107 if (opiechallenge(&opie, principal, challenge) != 0 && 108 openpam_get_option(pamh, PAM_OPT_NO_FAKE_PROMPTS)) 109 return (PAM_AUTH_ERR); 110 111 /* 112 * It doesn't make sense to use a password that has already been 113 * typed in, since we haven't presented the challenge to the user 114 * yet, so clear the stored password. 115 */ 116 pam_set_item(pamh, PAM_AUTHTOK, NULL); 117 118 style = PAM_PROMPT_ECHO_OFF; 119 for (i = 0; i < 2; i++) { 120 retval = pam_prompt(pamh, style, &response, 121 promptstr[i], challenge); 122 if (retval != PAM_SUCCESS) { 123 opieunlock(); 124 return (retval); 125 } 126 127 PAM_LOG("Completed challenge %d: %s", i, response); 128 129 if (response[0] != '\0') 130 break; 131 132 /* Second time round, echo the password */ 133 style = PAM_PROMPT_ECHO_ON; 134 } 135 136 pam_set_item(pamh, PAM_AUTHTOK, response); 137 138 /* 139 * Opieverify is supposed to return -1 only if an error occurs. 140 * But it returns -1 even if the response string isn't in the form 141 * it expects. Thus we can't log an error and can only check for 142 * success or lack thereof. 143 */ 144 retval = opieverify(&opie, response); 145 free(response); 146 return (retval == 0 ? PAM_SUCCESS : PAM_AUTH_ERR); 147} 148 149PAM_EXTERN int 150pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, 151 int argc __unused, const char *argv[] __unused) 152{ 153 154 return (PAM_SUCCESS); 155} 156 157PAM_MODULE_ENTRY("pam_opie"); 158