14Srgrimes/*- 24Srgrimes * Copyright (c) 2002-2003 Networks Associates Technology, Inc. 34Srgrimes * Copyright (c) 2004-2011 Dag-Erling Sm��rgrav 44Srgrimes * All rights reserved. 54Srgrimes * 64Srgrimes * This software was developed for the FreeBSD Project by ThinkSec AS and 74Srgrimes * Network Associates Laboratories, the Security Research Division of 84Srgrimes * Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 94Srgrimes * ("CBOSS"), as part of the DARPA CHATS research program. 104Srgrimes * 114Srgrimes * Redistribution and use in source and binary forms, with or without 124Srgrimes * modification, are permitted provided that the following conditions 134Srgrimes * are met: 144Srgrimes * 1. Redistributions of source code must retain the above copyright 154Srgrimes * notice, this list of conditions and the following disclaimer. 164Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 174Srgrimes * notice, this list of conditions and the following disclaimer in the 184Srgrimes * documentation and/or other materials provided with the distribution. 194Srgrimes * 3. The name of the author may not be used to endorse or promote 204Srgrimes * products derived from this software without specific prior written 214Srgrimes * permission. 224Srgrimes * 234Srgrimes * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 244Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 254Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 264Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 274Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 284Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 294Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 304Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 314Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32551Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3350477Speter * SUCH DAMAGE. 344Srgrimes * 354Srgrimes * $Id: pam_get_authtok.c 670 2013-03-17 19:26:07Z des $ 36196994Sphk */ 37196994Sphk 38196994Sphk#ifdef HAVE_CONFIG_H 39196994Sphk# include "config.h" 40249722Stijl#endif 41249722Stijl 424Srgrimes#include <sys/param.h> 434Srgrimes 444Srgrimes#include <stdlib.h> 4568498Sasmodai#include <string.h> 4668498Sasmodai 47154128Simp#include <security/pam_appl.h> 48223440Sjhb#include <security/openpam.h> 49154128Simp 50154128Simp#include "openpam_impl.h" 5144364Simp 52551Srgrimesstatic const char authtok_prompt[] = "Password:"; 5344364Simpstatic const char authtok_prompt_remote[] = "Password for %u@%h:"; 5444364Simpstatic const char oldauthtok_prompt[] = "Old Password:"; 5538673Skatostatic const char newauthtok_prompt[] = "New Password:"; 5644364Simp 5736977Sbde/* 5836977Sbde * OpenPAM extension 59177661Sjb * 60224207Sattilio * Retrieve authentication token 61183525Sjhb */ 62224207Sattilio 6328354Sfsmpint 6466296Spspam_get_authtok(pam_handle_t *pamh, 65177661Sjb int item, 664Srgrimes const char **authtok, 67250338Sattilio const char *prompt) 68250338Sattilio{ 69250338Sattilio char prompt_buf[1024]; 70250338Sattilio size_t prompt_size; 7168498Sasmodai const void *oldauthtok, *prevauthtok, *promptp; 7268498Sasmodai const char *prompt_option, *default_prompt; 73195376Ssam const void *lhost, *rhost; 74195376Ssam char *resp, *resp2; 75195376Ssam int pitem, r, style, twice; 76195376Ssam 77195376Ssam ENTER(); 78195376Ssam if (pamh == NULL || authtok == NULL) 79195376Ssam RETURNC(PAM_SYSTEM_ERR); 804Srgrimes *authtok = NULL; 81191278Srwatson twice = 0; 82191278Srwatson switch (item) { 83191278Srwatson case PAM_AUTHTOK: 84191278Srwatson pitem = PAM_AUTHTOK_PROMPT; 85192331Sjhb prompt_option = "authtok_prompt"; 86191276Srwatson default_prompt = authtok_prompt; 87191276Srwatson r = pam_get_item(pamh, PAM_RHOST, &rhost); 8815543Sphk if (r == PAM_SUCCESS && rhost != NULL) { 8915565Sphk r = pam_get_item(pamh, PAM_HOST, &lhost); 901045Sdg if (r == PAM_SUCCESS && lhost != NULL) { 9115543Sphk if (strcmp(rhost, lhost) != 0) 9215565Sphk default_prompt = authtok_prompt_remote; 93282065Skib } 94112841Sjake } 95112841Sjake r = pam_get_item(pamh, PAM_OLDAUTHTOK, &oldauthtok); 96183343Skmacy if (r == PAM_SUCCESS && oldauthtok != NULL) { 97112841Sjake default_prompt = newauthtok_prompt; 98111363Sjake twice = 1; 99111363Sjake } 100183343Skmacy break; 101112841Sjake case PAM_OLDAUTHTOK: 102111363Sjake pitem = PAM_OLDAUTHTOK_PROMPT; 103111363Sjake prompt_option = "oldauthtok_prompt"; 104111363Sjake default_prompt = oldauthtok_prompt; 10515543Sphk twice = 0; 10615565Sphk break; 10727950Sdyson default: 1084Srgrimes RETURNC(PAM_SYMBOL_ERR); 109197316Salc } 110197316Salc if (openpam_get_option(pamh, "try_first_pass") || 11127993Sdyson openpam_get_option(pamh, "use_first_pass")) { 11282309Speter r = pam_get_item(pamh, item, &prevauthtok); 11383366Sjulian if (r == PAM_SUCCESS && prevauthtok != NULL) { 11483366Sjulian *authtok = prevauthtok; 11582309Speter RETURNC(PAM_SUCCESS); 116116355Salc } else if (openpam_get_option(pamh, "use_first_pass")) { 1174Srgrimes RETURNC(r == PAM_SUCCESS ? PAM_AUTH_ERR : r); 1184Srgrimes } 119239730Sdes } 120239730Sdes /* pam policy overrides the module's choice */ 121239730Sdes if ((promptp = openpam_get_option(pamh, prompt_option)) != NULL) 122239730Sdes prompt = promptp; 123239730Sdes /* no prompt provided, see if there is one tucked away somewhere */ 124239730Sdes if (prompt == NULL) 125239730Sdes if (pam_get_item(pamh, pitem, &promptp) && promptp != NULL) 126239730Sdes prompt = promptp; 127239730Sdes /* fall back to hardcoded default */ 128239730Sdes if (prompt == NULL) 129239730Sdes prompt = default_prompt; 130239730Sdes /* expand */ 131239730Sdes prompt_size = sizeof prompt_buf; 132239730Sdes r = openpam_subst(pamh, prompt_buf, &prompt_size, prompt); 13381933Sdillon if (r == PAM_SUCCESS && prompt_size <= sizeof prompt_buf) 134102738Sdillon prompt = prompt_buf; 135102738Sdillon style = openpam_get_option(pamh, "echo_pass") ? 136248789Skib PAM_PROMPT_ECHO_ON : PAM_PROMPT_ECHO_OFF; 137248789Skib r = pam_prompt(pamh, style, &resp, "%s", prompt); 138248789Skib if (r != PAM_SUCCESS) 13981933Sdillon RETURNC(r); 14081933Sdillon if (twice) { 141248789Skib r = pam_prompt(pamh, style, &resp2, "Retype %s", prompt); 14281933Sdillon if (r != PAM_SUCCESS) { 14381933Sdillon FREE(resp); 14481933Sdillon RETURNC(r); 1454Srgrimes } 1464Srgrimes if (strcmp(resp, resp2) != 0) 14740286Sdg FREE(resp); 14840286Sdg FREE(resp2); 149112569Sjake } 150112569Sjake if (resp == NULL) 1511549Srgrimes RETURNC(PAM_TRY_AGAIN); 152112569Sjake r = pam_set_item(pamh, item, resp); 153112569Sjake FREE(resp); 1541045Sdg if (r != PAM_SUCCESS) 155112569Sjake RETURNC(r); 156112569Sjake r = pam_get_item(pamh, item, (const void **)authtok); 157584Srgrimes RETURNC(r); 15844157Sluoqi} 15944157Sluoqi 160196994Sphk/* 161 * Error codes: 162 * 163 * =pam_get_item 164 * =pam_prompt 165 * =pam_set_item 166 * !PAM_SYMBOL_ERR 167 * PAM_TRY_AGAIN 168 */ 169 170/** 171 * The =pam_get_authtok function either prompts the user for an 172 * authentication token or retrieves a cached authentication token, 173 * depending on circumstances. 174 * Either way, a pointer to the authentication token is stored in the 175 * location pointed to by the =authtok argument, and the corresponding PAM 176 * item is updated. 177 * 178 * The =item argument must have one of the following values: 179 * 180 * =PAM_AUTHTOK: 181 * Returns the current authentication token, or the new token 182 * when changing authentication tokens. 183 * =PAM_OLDAUTHTOK: 184 * Returns the previous authentication token when changing 185 * authentication tokens. 186 * 187 * The =prompt argument specifies a prompt to use if no token is cached. 188 * If it is =NULL, the =PAM_AUTHTOK_PROMPT or =PAM_OLDAUTHTOK_PROMPT item, 189 * as appropriate, will be used. 190 * If that item is also =NULL, a hardcoded default prompt will be used. 191 * Additionally, when =pam_get_authtok is called from a service module, 192 * the prompt may be affected by module options as described below. 193 * The prompt is then expanded using =openpam_subst before it is passed to 194 * the conversation function. 195 * 196 * If =item is set to =PAM_AUTHTOK and there is a non-null =PAM_OLDAUTHTOK 197 * item, =pam_get_authtok will ask the user to confirm the new token by 198 * retyping it. 199 * If there is a mismatch, =pam_get_authtok will return =PAM_TRY_AGAIN. 200 * 201 * MODULE OPTIONS 202 * 203 * When called by a service module, =pam_get_authtok will recognize the 204 * following module options: 205 * 206 * ;authtok_prompt: 207 * Prompt to use when =item is set to =PAM_AUTHTOK. 208 * This option overrides both the =prompt argument and the 209 * =PAM_AUTHTOK_PROMPT item. 210 * ;echo_pass: 211 * If the application's conversation function allows it, this 212 * lets the user see what they are typing. 213 * This should only be used for non-reusable authentication 214 * tokens. 215 * ;oldauthtok_prompt: 216 * Prompt to use when =item is set to =PAM_OLDAUTHTOK. 217 * This option overrides both the =prompt argument and the 218 * =PAM_OLDAUTHTOK_PROMPT item. 219 * ;try_first_pass: 220 * If the requested item is non-null, return it without 221 * prompting the user. 222 * Typically, the service module will verify the token, and 223 * if it does not match, clear the item before calling 224 * =pam_get_authtok a second time. 225 * ;use_first_pass: 226 * Do not prompt the user at all; just return the cached 227 * value, or =PAM_AUTH_ERR if there is none. 228 * 229 * >pam_conv 230 * >pam_get_item 231 * >pam_get_user 232 * >openpam_get_option 233 * >openpam_subst 234 */ 235