pam_radius.c revision 1.2
1 /* $NetBSD: pam_radius.c,v 1.2 2004/12/12 08:18:46 christos Exp $ */ 2 3 /*- 4 * Copyright 1998 Juniper Networks, Inc. 5 * All rights reserved. 6 * Copyright (c) 2001-2003 Networks Associates Technology, Inc. 7 * All rights reserved. 8 * 9 * Portions of this software were developed for the FreeBSD Project by 10 * ThinkSec AS and NAI Labs, the Security Research Division of Network 11 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 12 * ("CBOSS"), as part of the DARPA CHATS research program. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. The name of the author may not be used to endorse or promote 23 * products derived from this software without specific prior written 24 * permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #ifdef __FreeBSD__ 41 __FBSDID("$FreeBSD: src/lib/libpam/modules/pam_radius/pam_radius.c,v 1.22 2004/06/25 12:32:45 kan Exp $"); 42 #else 43 __RCSID("$NetBSD: pam_radius.c,v 1.2 2004/12/12 08:18:46 christos Exp $"); 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/types.h> 48 #include <sys/socket.h> 49 #include <netdb.h> 50 #include <pwd.h> 51 #include <radlib.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <syslog.h> 55 #include <unistd.h> 56 57 #define PAM_SM_AUTH 58 59 #include <security/pam_appl.h> 60 #include <security/pam_modules.h> 61 #include <security/pam_mod_misc.h> 62 63 #define PAM_OPT_CONF "conf" 64 #define PAM_OPT_TEMPLATE_USER "template_user" 65 #define PAM_OPT_NAS_ID "nas_id" 66 #define PAM_OPT_NAS_IPADDR "nas_ipaddr" 67 68 #define MAX_CHALLENGE_MSGS 10 69 #define PASSWORD_PROMPT "RADIUS Password:" 70 71 static int build_access_request(struct rad_handle *, const char *, 72 const char *, const char *, const char *, const void *, 73 size_t); 74 static int do_accept(pam_handle_t *, struct rad_handle *); 75 static int do_challenge(pam_handle_t *, struct rad_handle *, 76 const char *); 77 78 /* 79 * Construct an access request, but don't send it. Returns 0 on success, 80 * -1 on failure. 81 */ 82 static int 83 build_access_request(struct rad_handle *radh, const char *user, 84 const char *pass, const char *nas_id, const char *nas_ipaddr, 85 const void *state, size_t state_len) 86 { 87 int error; 88 char host[MAXHOSTNAMELEN]; 89 struct sockaddr_in *haddr; 90 struct addrinfo hints; 91 struct addrinfo *res; 92 93 if (rad_create_request(radh, RAD_ACCESS_REQUEST) == -1) { 94 syslog(LOG_CRIT, "rad_create_request: %s", rad_strerror(radh)); 95 return (-1); 96 } 97 if (nas_id == NULL || 98 (nas_ipaddr != NULL && strlen(nas_ipaddr) == 0)) { 99 if (gethostname(host, sizeof host) != -1) { 100 if (nas_id == NULL) 101 nas_id = host; 102 if (nas_ipaddr != NULL && strlen(nas_ipaddr) == 0) 103 nas_ipaddr = host; 104 } 105 } 106 if ((user != NULL && 107 rad_put_string(radh, RAD_USER_NAME, user) == -1) || 108 (pass != NULL && 109 rad_put_string(radh, RAD_USER_PASSWORD, pass) == -1) || 110 (nas_id != NULL && 111 rad_put_string(radh, RAD_NAS_IDENTIFIER, nas_id) == -1)) { 112 syslog(LOG_CRIT, "rad_put_string: %s", rad_strerror(radh)); 113 return (-1); 114 } 115 if (nas_ipaddr != NULL) { 116 memset(&hints, 0, sizeof(hints)); 117 hints.ai_family = PF_INET; 118 if (getaddrinfo(nas_ipaddr, NULL, &hints, &res) == 0 && 119 res != NULL) { 120 (struct sockaddr *)haddr = res->ai_addr; 121 error = rad_put_addr(radh, RAD_NAS_IP_ADDRESS, 122 haddr->sin_addr); 123 freeaddrinfo(res); 124 if (error == -1) { 125 syslog(LOG_CRIT, "rad_put_addr: %s", 126 rad_strerror(radh)); 127 return (-1); 128 } 129 } 130 } 131 if (state != NULL && rad_put_attr(radh, RAD_STATE, state, 132 state_len) == -1) { 133 syslog(LOG_CRIT, "rad_put_attr: %s", rad_strerror(radh)); 134 return (-1); 135 } 136 if (rad_put_int(radh, RAD_SERVICE_TYPE, RAD_AUTHENTICATE_ONLY) == -1) { 137 syslog(LOG_CRIT, "rad_put_int: %s", rad_strerror(radh)); 138 return (-1); 139 } 140 return (0); 141 } 142 143 static int 144 do_accept(pam_handle_t *pamh, struct rad_handle *radh) 145 { 146 int attrtype; 147 const void *attrval; 148 size_t attrlen; 149 char *s; 150 151 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 152 if (attrtype == RAD_USER_NAME) { 153 s = rad_cvt_string(attrval, attrlen); 154 if (s == NULL) { 155 syslog(LOG_CRIT, 156 "rad_cvt_string: out of memory"); 157 return (-1); 158 } 159 pam_set_item(pamh, PAM_USER, s); 160 free(s); 161 } 162 } 163 if (attrtype == -1) { 164 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 165 return (-1); 166 } 167 return (0); 168 } 169 170 static int 171 do_challenge(pam_handle_t *pamh, struct rad_handle *radh, const char *user) 172 { 173 int retval; 174 int attrtype; 175 const void *attrval; 176 size_t attrlen; 177 const void *state; 178 size_t statelen; 179 struct pam_message msgs[MAX_CHALLENGE_MSGS]; 180 const struct pam_message *msg_ptrs[MAX_CHALLENGE_MSGS]; 181 struct pam_response *resp; 182 int num_msgs; 183 const void *item; 184 const struct pam_conv *conv; 185 186 state = NULL; 187 statelen = 0; 188 num_msgs = 0; 189 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 190 switch (attrtype) { 191 192 case RAD_STATE: 193 state = attrval; 194 statelen = attrlen; 195 break; 196 197 case RAD_REPLY_MESSAGE: 198 if (num_msgs >= MAX_CHALLENGE_MSGS) { 199 syslog(LOG_CRIT, 200 "Too many RADIUS challenge messages"); 201 return (PAM_SERVICE_ERR); 202 } 203 msgs[num_msgs].msg = rad_cvt_string(attrval, attrlen); 204 if (msgs[num_msgs].msg == NULL) { 205 syslog(LOG_CRIT, 206 "rad_cvt_string: out of memory"); 207 return (PAM_SERVICE_ERR); 208 } 209 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 210 msg_ptrs[num_msgs] = &msgs[num_msgs]; 211 num_msgs++; 212 break; 213 } 214 } 215 if (attrtype == -1) { 216 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 217 return (PAM_SERVICE_ERR); 218 } 219 if (num_msgs == 0) { 220 msgs[num_msgs].msg = strdup("(null RADIUS challenge): "); 221 if (msgs[num_msgs].msg == NULL) { 222 syslog(LOG_CRIT, "Out of memory"); 223 return (PAM_SERVICE_ERR); 224 } 225 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 226 msg_ptrs[num_msgs] = &msgs[num_msgs]; 227 num_msgs++; 228 } 229 msgs[num_msgs-1].msg_style = PAM_PROMPT_ECHO_ON; 230 if ((retval = pam_get_item(pamh, PAM_CONV, &item)) != PAM_SUCCESS) { 231 syslog(LOG_CRIT, "do_challenge: cannot get PAM_CONV"); 232 return (retval); 233 } 234 conv = (const struct pam_conv *)item; 235 if ((retval = conv->conv(num_msgs, msg_ptrs, &resp, 236 conv->appdata_ptr)) != PAM_SUCCESS) 237 return (retval); 238 if (build_access_request(radh, user, resp[num_msgs-1].resp, NULL, 239 NULL, state, statelen) == -1) 240 return (PAM_SERVICE_ERR); 241 memset(resp[num_msgs-1].resp, 0, strlen(resp[num_msgs-1].resp)); 242 free(resp[num_msgs-1].resp); 243 free(resp); 244 while (num_msgs > 0) 245 free(msgs[--num_msgs].msg); 246 return (PAM_SUCCESS); 247 } 248 249 PAM_EXTERN int 250 pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 251 int argc __unused, const char *argv[] __unused) 252 { 253 struct rad_handle *radh; 254 const char *user, *pass; 255 const void *tmpuser; 256 const char *conf_file, *template_user, *nas_id, *nas_ipaddr; 257 int retval; 258 int e; 259 260 conf_file = openpam_get_option(pamh, PAM_OPT_CONF); 261 template_user = openpam_get_option(pamh, PAM_OPT_TEMPLATE_USER); 262 nas_id = openpam_get_option(pamh, PAM_OPT_NAS_ID); 263 nas_ipaddr = openpam_get_option(pamh, PAM_OPT_NAS_IPADDR); 264 265 retval = pam_get_user(pamh, &user, NULL); 266 if (retval != PAM_SUCCESS) 267 return (retval); 268 269 PAM_LOG("Got user: %s", user); 270 271 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 272 if (retval != PAM_SUCCESS) 273 return (retval); 274 275 PAM_LOG("Got password"); 276 277 radh = rad_open(); 278 if (radh == NULL) { 279 syslog(LOG_CRIT, "rad_open failed"); 280 return (PAM_SERVICE_ERR); 281 } 282 283 PAM_LOG("Radius opened"); 284 285 if (rad_config(radh, conf_file) == -1) { 286 syslog(LOG_ALERT, "rad_config: %s", rad_strerror(radh)); 287 rad_close(radh); 288 return (PAM_SERVICE_ERR); 289 } 290 291 PAM_LOG("Radius config file read"); 292 293 if (build_access_request(radh, user, pass, nas_id, nas_ipaddr, NULL, 294 0) == -1) { 295 rad_close(radh); 296 return (PAM_SERVICE_ERR); 297 } 298 299 PAM_LOG("Radius build access done"); 300 301 for (;;) { 302 switch (rad_send_request(radh)) { 303 304 case RAD_ACCESS_ACCEPT: 305 e = do_accept(pamh, radh); 306 rad_close(radh); 307 if (e == -1) 308 return (PAM_SERVICE_ERR); 309 if (template_user != NULL) { 310 311 PAM_LOG("Trying template user: %s", 312 template_user); 313 314 /* 315 * If the given user name doesn't exist in 316 * the local password database, change it 317 * to the value given in the "template_user" 318 * option. 319 */ 320 retval = pam_get_item(pamh, PAM_USER, &tmpuser); 321 if (retval != PAM_SUCCESS) 322 return (retval); 323 if (getpwnam(tmpuser) == NULL) { 324 pam_set_item(pamh, PAM_USER, 325 template_user); 326 PAM_LOG("Using template user"); 327 } 328 329 } 330 return (PAM_SUCCESS); 331 332 case RAD_ACCESS_REJECT: 333 rad_close(radh); 334 PAM_VERBOSE_ERROR("Radius rejection"); 335 return (PAM_AUTH_ERR); 336 337 case RAD_ACCESS_CHALLENGE: 338 retval = do_challenge(pamh, radh, user); 339 if (retval != PAM_SUCCESS) { 340 rad_close(radh); 341 return (retval); 342 } 343 break; 344 345 case -1: 346 syslog(LOG_CRIT, "rad_send_request: %s", 347 rad_strerror(radh)); 348 rad_close(radh); 349 PAM_VERBOSE_ERROR("Radius failure"); 350 return (PAM_AUTHINFO_UNAVAIL); 351 352 default: 353 syslog(LOG_CRIT, 354 "rad_send_request: unexpected return value"); 355 rad_close(radh); 356 PAM_VERBOSE_ERROR("Radius error"); 357 return (PAM_SERVICE_ERR); 358 } 359 } 360 } 361 362 PAM_EXTERN int 363 pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, 364 int argc __unused, const char *argv[] __unused) 365 { 366 367 return (PAM_SUCCESS); 368 } 369 370 PAM_MODULE_ENTRY("pam_radius"); 371
Indexes created Sat Oct 11 08:10:02 GMT 2025