1 /*- 2 * Copyright 1998 Juniper Networks, Inc. 3 * All rights reserved. 4 * Copyright (c) 2001-2003 Networks Associates Technology, Inc. 5 * All rights reserved. 6 * 7 * Portions of this software were developed for the FreeBSD Project by 8 * ThinkSec AS and NAI Labs, the Security Research Division of Network 9 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 10 * ("CBOSS"), as part of the DARPA CHATS research program. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. The name of the author may not be used to endorse or promote 21 * products derived from this software without specific prior written 22 * permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/socket.h> 42 #include <netdb.h> 43 #include <pwd.h> 44 #include <radlib.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <syslog.h> 48 #include <unistd.h> 49 50 #define PAM_SM_AUTH 51 52 #include <security/pam_appl.h> 53 #include <security/pam_modules.h> 54 #include <security/pam_mod_misc.h> 55 56 #define PAM_OPT_CONF "conf" 57 #define PAM_OPT_TEMPLATE_USER "template_user" 58 #define PAM_OPT_NAS_ID "nas_id" 59 #define PAM_OPT_NAS_IPADDR "nas_ipaddr" 60 61 #define MAX_CHALLENGE_MSGS 10 62 #define PASSWORD_PROMPT "RADIUS Password:" 63 64 static int build_access_request(struct rad_handle *, const char *, 65 const char *, const char *, const char *, const void *, 66 size_t); 67 static int do_accept(pam_handle_t *, struct rad_handle *); 68 static int do_challenge(pam_handle_t *, struct rad_handle *, 69 const char *, const char *, const char *); 70 71 /* 72 * Construct an access request, but don't send it. Returns 0 on success, 73 * -1 on failure. 74 */ 75 static int 76 build_access_request(struct rad_handle *radh, const char *user, 77 const char *pass, const char *nas_id, const char *nas_ipaddr, 78 const void *state, size_t state_len) 79 { 80 int error; 81 char host[MAXHOSTNAMELEN]; 82 struct sockaddr_in *haddr; 83 struct addrinfo hints; 84 struct addrinfo *res; 85 86 if (rad_create_request(radh, RAD_ACCESS_REQUEST) == -1) { 87 syslog(LOG_CRIT, "rad_create_request: %s", rad_strerror(radh)); 88 return (-1); 89 } 90 if (nas_id == NULL || 91 (nas_ipaddr != NULL && strlen(nas_ipaddr) == 0)) { 92 if (gethostname(host, sizeof host) != -1) { 93 if (nas_id == NULL) 94 nas_id = host; 95 if (nas_ipaddr != NULL && strlen(nas_ipaddr) == 0) 96 nas_ipaddr = host; 97 } 98 } 99 if ((user != NULL && 100 rad_put_string(radh, RAD_USER_NAME, user) == -1) || 101 (pass != NULL && 102 rad_put_string(radh, RAD_USER_PASSWORD, pass) == -1) || 103 (nas_id != NULL && 104 rad_put_string(radh, RAD_NAS_IDENTIFIER, nas_id) == -1)) { 105 syslog(LOG_CRIT, "rad_put_string: %s", rad_strerror(radh)); 106 return (-1); 107 } 108 if (nas_ipaddr != NULL) { 109 memset(&hints, 0, sizeof(hints)); 110 hints.ai_family = AF_INET; 111 if (getaddrinfo(nas_ipaddr, NULL, &hints, &res) == 0 && 112 res != NULL && res->ai_family == AF_INET) { 113 haddr = (struct sockaddr_in *)res->ai_addr; 114 error = rad_put_addr(radh, RAD_NAS_IP_ADDRESS, 115 haddr->sin_addr); 116 freeaddrinfo(res); 117 if (error == -1) { 118 syslog(LOG_CRIT, "rad_put_addr: %s", 119 rad_strerror(radh)); 120 return (-1); 121 } 122 } 123 } 124 if (state != NULL && rad_put_attr(radh, RAD_STATE, state, 125 state_len) == -1) { 126 syslog(LOG_CRIT, "rad_put_attr: %s", rad_strerror(radh)); 127 return (-1); 128 } 129 if (rad_put_int(radh, RAD_SERVICE_TYPE, RAD_AUTHENTICATE_ONLY) == -1) { 130 syslog(LOG_CRIT, "rad_put_int: %s", rad_strerror(radh)); 131 return (-1); 132 } 133 return (0); 134 } 135 136 static int 137 do_accept(pam_handle_t *pamh, struct rad_handle *radh) 138 { 139 int attrtype; 140 const void *attrval; 141 size_t attrlen; 142 char *s; 143 144 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 145 if (attrtype == RAD_USER_NAME) { 146 s = rad_cvt_string(attrval, attrlen); 147 if (s == NULL) { 148 syslog(LOG_CRIT, 149 "rad_cvt_string: out of memory"); 150 return (-1); 151 } 152 pam_set_item(pamh, PAM_USER, s); 153 free(s); 154 } 155 } 156 if (attrtype == -1) { 157 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 158 return (-1); 159 } 160 return (0); 161 } 162 163 static int 164 do_challenge(pam_handle_t *pamh, struct rad_handle *radh, const char *user, 165 const char *nas_id, const char *nas_ipaddr) 166 { 167 int retval; 168 int attrtype; 169 const void *attrval; 170 size_t attrlen; 171 const void *state; 172 size_t statelen; 173 struct pam_message msgs[MAX_CHALLENGE_MSGS]; 174 const struct pam_message *msg_ptrs[MAX_CHALLENGE_MSGS]; 175 struct pam_response *resp; 176 int num_msgs; 177 const void *item; 178 const struct pam_conv *conv; 179 180 state = NULL; 181 statelen = 0; 182 num_msgs = 0; 183 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 184 switch (attrtype) { 185 186 case RAD_STATE: 187 state = attrval; 188 statelen = attrlen; 189 break; 190 191 case RAD_REPLY_MESSAGE: 192 if (num_msgs >= MAX_CHALLENGE_MSGS) { 193 syslog(LOG_CRIT, 194 "Too many RADIUS challenge messages"); 195 return (PAM_SERVICE_ERR); 196 } 197 msgs[num_msgs].msg = rad_cvt_string(attrval, attrlen); 198 if (msgs[num_msgs].msg == NULL) { 199 syslog(LOG_CRIT, 200 "rad_cvt_string: out of memory"); 201 return (PAM_SERVICE_ERR); 202 } 203 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 204 msg_ptrs[num_msgs] = &msgs[num_msgs]; 205 num_msgs++; 206 break; 207 } 208 } 209 if (attrtype == -1) { 210 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 211 return (PAM_SERVICE_ERR); 212 } 213 if (num_msgs == 0) { 214 msgs[num_msgs].msg = strdup("(null RADIUS challenge): "); 215 if (msgs[num_msgs].msg == NULL) { 216 syslog(LOG_CRIT, "Out of memory"); 217 return (PAM_SERVICE_ERR); 218 } 219 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 220 msg_ptrs[num_msgs] = &msgs[num_msgs]; 221 num_msgs++; 222 } 223 msgs[num_msgs-1].msg_style = PAM_PROMPT_ECHO_ON; 224 if ((retval = pam_get_item(pamh, PAM_CONV, &item)) != PAM_SUCCESS) { 225 syslog(LOG_CRIT, "do_challenge: cannot get PAM_CONV"); 226 return (retval); 227 } 228 conv = (const struct pam_conv *)item; 229 if ((retval = conv->conv(num_msgs, msg_ptrs, &resp, 230 conv->appdata_ptr)) != PAM_SUCCESS) 231 return (retval); 232 if (build_access_request(radh, user, resp[num_msgs-1].resp, nas_id, 233 nas_ipaddr, state, statelen) == -1) 234 return (PAM_SERVICE_ERR); 235 memset(resp[num_msgs-1].resp, 0, strlen(resp[num_msgs-1].resp)); 236 free(resp[num_msgs-1].resp); 237 free(resp); 238 while (num_msgs > 0) 239 free(msgs[--num_msgs].msg); 240 return (PAM_SUCCESS); 241 } 242 243 PAM_EXTERN int 244 pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 245 int argc __unused, const char *argv[] __unused) 246 { 247 struct rad_handle *radh; 248 const char *user, *pass; 249 const void *tmpuser; 250 const char *conf_file, *template_user, *nas_id, *nas_ipaddr; 251 int retval; 252 int e; 253 254 conf_file = openpam_get_option(pamh, PAM_OPT_CONF); 255 template_user = openpam_get_option(pamh, PAM_OPT_TEMPLATE_USER); 256 nas_id = openpam_get_option(pamh, PAM_OPT_NAS_ID); 257 nas_ipaddr = openpam_get_option(pamh, PAM_OPT_NAS_IPADDR); 258 259 retval = pam_get_user(pamh, &user, NULL); 260 if (retval != PAM_SUCCESS) 261 return (retval); 262 263 PAM_LOG("Got user: %s", user); 264 265 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 266 if (retval != PAM_SUCCESS) 267 return (retval); 268 269 PAM_LOG("Got password"); 270 271 radh = rad_open(); 272 if (radh == NULL) { 273 syslog(LOG_CRIT, "rad_open failed"); 274 return (PAM_SERVICE_ERR); 275 } 276 277 PAM_LOG("Radius opened"); 278 279 if (rad_config(radh, conf_file) == -1) { 280 syslog(LOG_ALERT, "rad_config: %s", rad_strerror(radh)); 281 rad_close(radh); 282 return (PAM_SERVICE_ERR); 283 } 284 285 PAM_LOG("Radius config file read"); 286 287 if (build_access_request(radh, user, pass, nas_id, nas_ipaddr, NULL, 288 0) == -1) { 289 rad_close(radh); 290 return (PAM_SERVICE_ERR); 291 } 292 293 PAM_LOG("Radius build access done"); 294 295 for (;;) { 296 switch (rad_send_request(radh)) { 297 298 case RAD_ACCESS_ACCEPT: 299 e = do_accept(pamh, radh); 300 rad_close(radh); 301 if (e == -1) 302 return (PAM_SERVICE_ERR); 303 if (template_user != NULL) { 304 305 PAM_LOG("Trying template user: %s", 306 template_user); 307 308 /* 309 * If the given user name doesn't exist in 310 * the local password database, change it 311 * to the value given in the "template_user" 312 * option. 313 */ 314 retval = pam_get_item(pamh, PAM_USER, &tmpuser); 315 if (retval != PAM_SUCCESS) 316 return (retval); 317 if (getpwnam(tmpuser) == NULL) { 318 pam_set_item(pamh, PAM_USER, 319 template_user); 320 PAM_LOG("Using template user"); 321 } 322 323 } 324 return (PAM_SUCCESS); 325 326 case RAD_ACCESS_REJECT: 327 rad_close(radh); 328 PAM_VERBOSE_ERROR("Radius rejection"); 329 return (PAM_AUTH_ERR); 330 331 case RAD_ACCESS_CHALLENGE: 332 retval = do_challenge(pamh, radh, user, nas_id, 333 nas_ipaddr); 334 if (retval != PAM_SUCCESS) { 335 rad_close(radh); 336 return (retval); 337 } 338 break; 339 340 case -1: 341 syslog(LOG_CRIT, "rad_send_request: %s", 342 rad_strerror(radh)); 343 rad_close(radh); 344 PAM_VERBOSE_ERROR("Radius failure"); 345 return (PAM_AUTHINFO_UNAVAIL); 346 347 default: 348 syslog(LOG_CRIT, 349 "rad_send_request: unexpected return value"); 350 rad_close(radh); 351 PAM_VERBOSE_ERROR("Radius error"); 352 return (PAM_SERVICE_ERR); 353 } 354 } 355 } 356 357 PAM_EXTERN int 358 pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, 359 int argc __unused, const char *argv[] __unused) 360 { 361 362 return (PAM_SUCCESS); 363 } 364 365 PAM_MODULE_ENTRY("pam_radius"); 366