pam_tacplus.c revision 84218
1/*- 2 * Copyright 1998 Juniper Networks, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_tacplus/pam_tacplus.c 84218 2001-09-30 22:11:06Z dillon $"); 29 30#include <sys/param.h> 31 32#include <pwd.h> 33#include <stdlib.h> 34#include <string.h> 35#include <syslog.h> 36#include <taclib.h> 37#include <unistd.h> 38 39#define PAM_SM_AUTH 40#include <security/pam_modules.h> 41 42#include "pam_mod_misc.h" 43 44enum { PAM_OPT_CONF=PAM_OPT_STD_MAX, PAM_OPT_TEMPLATE_USER }; 45 46static struct opttab other_options[] = { 47 { "conf", PAM_OPT_CONF }, 48 { "template_user", PAM_OPT_TEMPLATE_USER }, 49 { NULL, 0 } 50}; 51 52typedef int (*set_func)(struct tac_handle *, const char *); 53 54static int do_item(pam_handle_t *, struct tac_handle *, int, 55 set_func, const char *); 56static char *get_msg(struct tac_handle *); 57static int set_msg(struct tac_handle *, const char *); 58 59static int 60do_item(pam_handle_t *pamh, struct tac_handle *tach, int item, 61 set_func func, const char *funcname) 62{ 63 int retval; 64 const void *value; 65 66 retval = pam_get_item(pamh, item, &value); 67 if (retval != PAM_SUCCESS) 68 return retval; 69 if (value != NULL && (*func)(tach, (const char *)value) == -1) { 70 syslog(LOG_CRIT, "%s: %s", funcname, tac_strerror(tach)); 71 tac_close(tach); 72 return PAM_SERVICE_ERR; 73 } 74 return PAM_SUCCESS; 75} 76 77static char * 78get_msg(struct tac_handle *tach) 79{ 80 char *msg; 81 82 msg = tac_get_msg(tach); 83 if (msg == NULL) { 84 syslog(LOG_CRIT, "tac_get_msg: %s", tac_strerror(tach)); 85 tac_close(tach); 86 return NULL; 87 } 88 return msg; 89} 90 91static int 92set_msg(struct tac_handle *tach, const char *msg) 93{ 94 if (tac_set_msg(tach, msg) == -1) { 95 syslog(LOG_CRIT, "tac_set_msg: %s", tac_strerror(tach)); 96 tac_close(tach); 97 return -1; 98 } 99 return 0; 100} 101 102PAM_EXTERN int 103pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, 104 const char **argv) 105{ 106 struct options options; 107 int retval; 108 struct tac_handle *tach; 109 char *conf_file; 110 char *template_user; 111 112 pam_std_option(&options, other_options, argc, argv); 113 114 PAM_LOG("Options processed"); 115 116 conf_file = NULL; 117 pam_test_option(&options, PAM_OPT_CONF, &conf_file); 118 template_user = NULL; 119 pam_test_option(&options, PAM_OPT_TEMPLATE_USER, &template_user); 120 121 tach = tac_open(); 122 if (tach == NULL) { 123 syslog(LOG_CRIT, "tac_open failed"); 124 PAM_RETURN(PAM_SERVICE_ERR); 125 } 126 if (tac_config(tach, conf_file) == -1) { 127 syslog(LOG_ALERT, "tac_config: %s", tac_strerror(tach)); 128 tac_close(tach); 129 PAM_RETURN(PAM_SERVICE_ERR); 130 } 131 if (tac_create_authen(tach, TAC_AUTHEN_LOGIN, TAC_AUTHEN_TYPE_ASCII, 132 TAC_AUTHEN_SVC_LOGIN) == -1) { 133 syslog(LOG_CRIT, "tac_create_authen: %s", tac_strerror(tach)); 134 tac_close(tach); 135 PAM_RETURN(PAM_SERVICE_ERR); 136 } 137 138 PAM_LOG("Done tac_open() ... tac_close()"); 139 140 retval = do_item(pamh, tach, PAM_USER, tac_set_user, "tac_set_user"); 141 if (retval != PAM_SUCCESS) 142 PAM_RETURN(retval); 143 144 PAM_LOG("Done user"); 145 146 retval = do_item(pamh, tach, PAM_TTY, tac_set_port, "tac_set_port"); 147 if (retval != PAM_SUCCESS) 148 PAM_RETURN(retval); 149 150 PAM_LOG("Done tty"); 151 152 retval = do_item(pamh, tach, PAM_RHOST, tac_set_rem_addr, 153 "tac_set_rem_addr"); 154 if (retval != PAM_SUCCESS) 155 PAM_RETURN(retval); 156 157 for ( ; ; ) { 158 char *srvr_msg; 159 size_t msg_len; 160 const char *user_msg; 161 char *data_msg; 162 int sflags; 163 int status; 164 165 sflags = tac_send_authen(tach); 166 if (sflags == -1) { 167 syslog(LOG_CRIT, "tac_send_authen: %s", 168 tac_strerror(tach)); 169 tac_close(tach); 170 PAM_RETURN(PAM_AUTHINFO_UNAVAIL); 171 } 172 status = TAC_AUTHEN_STATUS(sflags); 173 if (!TAC_AUTHEN_NOECHO(sflags)) 174 pam_set_option(&options, PAM_OPT_ECHO_PASS); 175 switch (status) { 176 177 case TAC_AUTHEN_STATUS_PASS: 178 tac_close(tach); 179 if (template_user != NULL) { 180 const void *item; 181 const char *user; 182 183 PAM_LOG("Trying template user: %s", 184 template_user); 185 186 /* 187 * If the given user name doesn't exist in 188 * the local password database, change it 189 * to the value given in the "template_user" 190 * option. 191 */ 192 retval = pam_get_item(pamh, PAM_USER, &item); 193 if (retval != PAM_SUCCESS) 194 PAM_RETURN(retval); 195 user = (const char *)item; 196 if (getpwnam(user) == NULL) { 197 pam_set_item(pamh, PAM_USER, 198 template_user); 199 PAM_LOG("Using template user"); 200 } 201 } 202 PAM_RETURN(PAM_SUCCESS); 203 204 case TAC_AUTHEN_STATUS_FAIL: 205 tac_close(tach); 206 PAM_VERBOSE_ERROR("TACACS+ authentication failed"); 207 PAM_RETURN(PAM_AUTH_ERR); 208 209 case TAC_AUTHEN_STATUS_GETUSER: 210 case TAC_AUTHEN_STATUS_GETPASS: 211 if ((srvr_msg = get_msg(tach)) == NULL) 212 PAM_RETURN(PAM_SERVICE_ERR); 213 if (status == TAC_AUTHEN_STATUS_GETUSER) 214 retval = pam_get_user(pamh, &user_msg, 215 srvr_msg[0] != '\0' ? srvr_msg : NULL); 216 else if (status == TAC_AUTHEN_STATUS_GETPASS) 217 retval = pam_get_pass(pamh, &user_msg, 218 srvr_msg[0] != '\0' ? srvr_msg : 219 "Password:", &options); 220 free(srvr_msg); 221 if (retval != PAM_SUCCESS) { 222 /* XXX - send a TACACS+ abort packet */ 223 tac_close(tach); 224 PAM_RETURN(retval); 225 } 226 if (set_msg(tach, user_msg) == -1) 227 PAM_RETURN(PAM_SERVICE_ERR); 228 break; 229 230 case TAC_AUTHEN_STATUS_GETDATA: 231 if ((srvr_msg = get_msg(tach)) == NULL) 232 PAM_RETURN(PAM_SERVICE_ERR); 233 retval = pam_prompt(pamh, 234 pam_test_option(&options, PAM_OPT_ECHO_PASS, NULL) 235 ? PAM_PROMPT_ECHO_ON : PAM_PROMPT_ECHO_OFF, 236 srvr_msg[0] != '\0' ? srvr_msg : "Data:", 237 &data_msg); 238 free(srvr_msg); 239 if (retval != PAM_SUCCESS) { 240 /* XXX - send a TACACS+ abort packet */ 241 tac_close(tach); 242 PAM_RETURN(retval); 243 } 244 retval = set_msg(tach, data_msg); 245 memset(data_msg, 0, strlen(data_msg)); 246 free(data_msg); 247 if (retval == -1) 248 PAM_RETURN(PAM_SERVICE_ERR); 249 break; 250 251 case TAC_AUTHEN_STATUS_ERROR: 252 srvr_msg = (char *)tac_get_data(tach, &msg_len); 253 if (srvr_msg != NULL && msg_len != 0) { 254 syslog(LOG_CRIT, "tac_send_authen:" 255 " server detected error: %s", srvr_msg); 256 free(srvr_msg); 257 } 258 else 259 syslog(LOG_CRIT, 260 "tac_send_authen: server detected error"); 261 tac_close(tach); 262 PAM_RETURN(PAM_AUTHINFO_UNAVAIL); 263 break; 264 265 case TAC_AUTHEN_STATUS_RESTART: 266 case TAC_AUTHEN_STATUS_FOLLOW: 267 default: 268 syslog(LOG_CRIT, 269 "tac_send_authen: unexpected status %#x", status); 270 tac_close(tach); 271 PAM_RETURN(PAM_AUTHINFO_UNAVAIL); 272 } 273 } 274} 275 276PAM_EXTERN int 277pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv) 278{ 279 return PAM_SUCCESS; 280} 281 282PAM_MODULE_ENTRY("pam_tacplus"); 283