1 /*- 2 * Copyright 1998 Juniper Networks, Inc. 3 * All rights reserved. 4 * Copyright (c) 2001,2002 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 <pwd.h> 42 #include <radlib.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <syslog.h> 46 #include <unistd.h> 47 48 #define PAM_SM_AUTH 49 50 #include <security/pam_appl.h> 51 #include <security/pam_modules.h> 52 #include <security/pam_mod_misc.h> 53 54 enum { 55 PAM_OPT_CONF = PAM_OPT_STD_MAX, 56 PAM_OPT_TEMPLATE_USER 57 }; 58 59 static struct opttab other_options[] = { 60 { "conf", PAM_OPT_CONF }, 61 { "template_user", PAM_OPT_TEMPLATE_USER }, 62 { NULL, 0 } 63 }; 64 65 #define MAX_CHALLENGE_MSGS 10 66 #define PASSWORD_PROMPT "RADIUS Password:" 67 68 static int build_access_request(struct rad_handle *, const char *, 69 const char *, const void *, size_t); 70 static int do_accept(pam_handle_t *, struct rad_handle *); 71 static int do_challenge(pam_handle_t *, struct rad_handle *, 72 const char *); 73 74 /* 75 * Construct an access request, but don't send it. Returns 0 on success, 76 * -1 on failure. 77 */ 78 static int 79 build_access_request(struct rad_handle *radh, const char *user, 80 const char *pass, const void *state, size_t state_len) 81 { 82 char host[MAXHOSTNAMELEN]; 83 84 if (rad_create_request(radh, RAD_ACCESS_REQUEST) == -1) { 85 syslog(LOG_CRIT, "rad_create_request: %s", rad_strerror(radh)); 86 return (-1); 87 } 88 if ((user != NULL && 89 rad_put_string(radh, RAD_USER_NAME, user) == -1) || 90 (pass != NULL && 91 rad_put_string(radh, RAD_USER_PASSWORD, pass) == -1) || 92 (gethostname(host, sizeof host) != -1 && 93 rad_put_string(radh, RAD_NAS_IDENTIFIER, host) == -1)) { 94 syslog(LOG_CRIT, "rad_put_string: %s", rad_strerror(radh)); 95 return (-1); 96 } 97 if (state != NULL && rad_put_attr(radh, RAD_STATE, state, 98 state_len) == -1) { 99 syslog(LOG_CRIT, "rad_put_attr: %s", rad_strerror(radh)); 100 return (-1); 101 } 102 if (rad_put_int(radh, RAD_SERVICE_TYPE, RAD_AUTHENTICATE_ONLY) == -1) { 103 syslog(LOG_CRIT, "rad_put_int: %s", rad_strerror(radh)); 104 return (-1); 105 } 106 return (0); 107 } 108 109 static int 110 do_accept(pam_handle_t *pamh, struct rad_handle *radh) 111 { 112 int attrtype; 113 const void *attrval; 114 size_t attrlen; 115 char *s; 116 117 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 118 if (attrtype == RAD_USER_NAME) { 119 s = rad_cvt_string(attrval, attrlen); 120 if (s == NULL) { 121 syslog(LOG_CRIT, 122 "rad_cvt_string: out of memory"); 123 return (-1); 124 } 125 pam_set_item(pamh, PAM_USER, s); 126 free(s); 127 } 128 } 129 if (attrtype == -1) { 130 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 131 return (-1); 132 } 133 return (0); 134 } 135 136 static int 137 do_challenge(pam_handle_t *pamh, struct rad_handle *radh, const char *user) 138 { 139 int retval; 140 int attrtype; 141 const void *attrval; 142 size_t attrlen; 143 const void *state; 144 size_t statelen; 145 struct pam_message msgs[MAX_CHALLENGE_MSGS]; 146 const struct pam_message *msg_ptrs[MAX_CHALLENGE_MSGS]; 147 struct pam_response *resp; 148 int num_msgs; 149 const void *item; 150 const struct pam_conv *conv; 151 152 state = NULL; 153 statelen = 0; 154 num_msgs = 0; 155 while ((attrtype = rad_get_attr(radh, &attrval, &attrlen)) > 0) { 156 switch (attrtype) { 157 158 case RAD_STATE: 159 state = attrval; 160 statelen = attrlen; 161 break; 162 163 case RAD_REPLY_MESSAGE: 164 if (num_msgs >= MAX_CHALLENGE_MSGS) { 165 syslog(LOG_CRIT, 166 "Too many RADIUS challenge messages"); 167 return (PAM_SERVICE_ERR); 168 } 169 msgs[num_msgs].msg = rad_cvt_string(attrval, attrlen); 170 if (msgs[num_msgs].msg == NULL) { 171 syslog(LOG_CRIT, 172 "rad_cvt_string: out of memory"); 173 return (PAM_SERVICE_ERR); 174 } 175 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 176 msg_ptrs[num_msgs] = &msgs[num_msgs]; 177 num_msgs++; 178 break; 179 } 180 } 181 if (attrtype == -1) { 182 syslog(LOG_CRIT, "rad_get_attr: %s", rad_strerror(radh)); 183 return (PAM_SERVICE_ERR); 184 } 185 if (num_msgs == 0) { 186 msgs[num_msgs].msg = strdup("(null RADIUS challenge): "); 187 if (msgs[num_msgs].msg == NULL) { 188 syslog(LOG_CRIT, "Out of memory"); 189 return (PAM_SERVICE_ERR); 190 } 191 msgs[num_msgs].msg_style = PAM_TEXT_INFO; 192 msg_ptrs[num_msgs] = &msgs[num_msgs]; 193 num_msgs++; 194 } 195 msgs[num_msgs-1].msg_style = PAM_PROMPT_ECHO_ON; 196 if ((retval = pam_get_item(pamh, PAM_CONV, &item)) != PAM_SUCCESS) { 197 syslog(LOG_CRIT, "do_challenge: cannot get PAM_CONV"); 198 return (retval); 199 } 200 conv = (const struct pam_conv *)item; 201 if ((retval = conv->conv(num_msgs, msg_ptrs, &resp, 202 conv->appdata_ptr)) != PAM_SUCCESS) 203 return (retval); 204 if (build_access_request(radh, user, resp[num_msgs-1].resp, state, 205 statelen) == -1) 206 return (PAM_SERVICE_ERR); 207 memset(resp[num_msgs-1].resp, 0, strlen(resp[num_msgs-1].resp)); 208 free(resp[num_msgs-1].resp); 209 free(resp); 210 while (num_msgs > 0) 211 free(msgs[--num_msgs].msg); 212 return (PAM_SUCCESS); 213 } 214 215 PAM_EXTERN int 216 pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, 217 int argc, const char *argv[]) 218 { 219 struct options options; 220 struct rad_handle *radh; 221 const char *user, *tmpuser, *pass; 222 char *conf_file, *template_user; 223 int retval; 224 int e; 225 226 pam_std_option(&options, other_options, argc, argv); 227 228 PAM_LOG("Options processed"); 229 230 conf_file = NULL; 231 pam_test_option(&options, PAM_OPT_CONF, &conf_file); 232 template_user = NULL; 233 pam_test_option(&options, PAM_OPT_TEMPLATE_USER, &template_user); 234 235 retval = pam_get_user(pamh, &user, NULL); 236 if (retval != PAM_SUCCESS) 237 return (retval); 238 239 PAM_LOG("Got user: %s", user); 240 241 retval = pam_get_authtok(pamh, PAM_AUTHTOK, &pass, PASSWORD_PROMPT); 242 if (retval != PAM_SUCCESS) 243 return (retval); 244 245 PAM_LOG("Got password"); 246 247 radh = rad_open(); 248 if (radh == NULL) { 249 syslog(LOG_CRIT, "rad_open failed"); 250 return (PAM_SERVICE_ERR); 251 } 252 253 PAM_LOG("Radius opened"); 254 255 if (rad_config(radh, conf_file) == -1) { 256 syslog(LOG_ALERT, "rad_config: %s", rad_strerror(radh)); 257 rad_close(radh); 258 return (PAM_SERVICE_ERR); 259 } 260 261 PAM_LOG("Radius config file read"); 262 263 if (build_access_request(radh, user, pass, NULL, 0) == -1) { 264 rad_close(radh); 265 return (PAM_SERVICE_ERR); 266 } 267 268 PAM_LOG("Radius build access done"); 269 270 for (;;) { 271 switch (rad_send_request(radh)) { 272 273 case RAD_ACCESS_ACCEPT: 274 e = do_accept(pamh, radh); 275 rad_close(radh); 276 if (e == -1) 277 return (PAM_SERVICE_ERR); 278 if (template_user != NULL) { 279 280 PAM_LOG("Trying template user: %s", 281 template_user); 282 283 /* 284 * If the given user name doesn't exist in 285 * the local password database, change it 286 * to the value given in the "template_user" 287 * option. 288 */ 289 retval = pam_get_item(pamh, PAM_USER, 290 (const void **)&tmpuser); 291 if (retval != PAM_SUCCESS) 292 return (retval); 293 if (getpwnam(tmpuser) == NULL) { 294 pam_set_item(pamh, PAM_USER, 295 template_user); 296 PAM_LOG("Using template user"); 297 } 298 299 } 300 return (PAM_SUCCESS); 301 302 case RAD_ACCESS_REJECT: 303 rad_close(radh); 304 PAM_VERBOSE_ERROR("Radius rejection"); 305 return (PAM_AUTH_ERR); 306 307 case RAD_ACCESS_CHALLENGE: 308 retval = do_challenge(pamh, radh, user); 309 if (retval != PAM_SUCCESS) { 310 rad_close(radh); 311 return (retval); 312 } 313 break; 314 315 case -1: 316 syslog(LOG_CRIT, "rad_send_request: %s", 317 rad_strerror(radh)); 318 rad_close(radh); 319 PAM_VERBOSE_ERROR("Radius failure"); 320 return (PAM_AUTHINFO_UNAVAIL); 321 322 default: 323 syslog(LOG_CRIT, 324 "rad_send_request: unexpected return value"); 325 rad_close(radh); 326 PAM_VERBOSE_ERROR("Radius error"); 327 return (PAM_SERVICE_ERR); 328 } 329 } 330 } 331 332 PAM_EXTERN int 333 pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, 334 int argc __unused, const char *argv[] __unused) 335 { 336 337 return (PAM_SUCCESS); 338 } 339 340 PAM_MODULE_ENTRY("pam_radius"); 341