contrib/hostapd-0.5.8/radius.c

   1 /*
   2  * hostapd / RADIUS message processing
   3  * Copyright (c) 2002-2005, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "radius.h"
  19 #include "md5.h"
  20 #include "crypto.h"
  21
  22
  23 struct radius_msg *radius_msg_new(u8 code, u8 identifier)
  24 {
  25         struct radius_msg *msg;
  26
  27         msg = os_malloc(sizeof(*msg));
  28         if (msg == NULL)
  29                 return NULL;
  30
  31         if (radius_msg_initialize(msg, RADIUS_DEFAULT_MSG_SIZE)) {
  32                 os_free(msg);
  33                 return NULL;
  34         }
  35
  36         radius_msg_set_hdr(msg, code, identifier);
  37
  38         return msg;
  39 }
  40
  41
  42 int radius_msg_initialize(struct radius_msg *msg, size_t init_len)
  43 {
  44         if (msg == NULL || init_len < sizeof(struct radius_hdr))
  45                 return -1;
  46
  47         os_memset(msg, 0, sizeof(*msg));
  48         msg->buf = wpa_zalloc(init_len);
  49         if (msg->buf == NULL)
  50                 return -1;
  51
  52         msg->buf_size = init_len;
  53         msg->hdr = (struct radius_hdr *) msg->buf;
  54         msg->buf_used = sizeof(*msg->hdr);
  55
  56         msg->attrs =
  57                 os_malloc(RADIUS_DEFAULT_ATTR_COUNT * sizeof(*msg->attrs));
  58         if (msg->attrs == NULL) {
  59                 os_free(msg->buf);
  60                 msg->buf = NULL;
  61                 msg->hdr = NULL;
  62                 return -1;
  63         }
  64
  65         msg->attr_size = RADIUS_DEFAULT_ATTR_COUNT;
  66         msg->attr_used = 0;
  67
  68         return 0;
  69 }
  70
  71
  72 void radius_msg_set_hdr(struct radius_msg *msg, u8 code, u8 identifier)
  73 {
  74         msg->hdr->code = code;
  75         msg->hdr->identifier = identifier;
  76 }
  77
  78
  79 void radius_msg_free(struct radius_msg *msg)
  80 {
  81         if (msg->buf != NULL) {
  82                 os_free(msg->buf);
  83                 msg->buf = NULL;
  84                 msg->hdr = NULL;
  85         }
  86         msg->buf_size = msg->buf_used = 0;
  87
  88         if (msg->attrs != NULL) {
  89                 os_free(msg->attrs);
  90                 msg->attrs = NULL;
  91         }
  92         msg->attr_size = msg->attr_used = 0;
  93 }
  94
  95
  96 static const char *radius_code_string(u8 code)
  97 {
  98         switch (code) {
  99         case RADIUS_CODE_ACCESS_REQUEST: return "Access-Request";
 100         case RADIUS_CODE_ACCESS_ACCEPT: return "Access-Accept";
 101         case RADIUS_CODE_ACCESS_REJECT: return "Access-Reject";
 102         case RADIUS_CODE_ACCOUNTING_REQUEST: return "Accounting-Request";
 103         case RADIUS_CODE_ACCOUNTING_RESPONSE: return "Accounting-Response";
 104         case RADIUS_CODE_ACCESS_CHALLENGE: return "Access-Challenge";
 105         case RADIUS_CODE_STATUS_SERVER: return "Status-Server";
 106         case RADIUS_CODE_STATUS_CLIENT: return "Status-Client";
 107         case RADIUS_CODE_RESERVED: return "Reserved";
 108         default: return "?Unknown?";
 109         }
 110 }
 111
 112
 113 struct radius_attr_type {
 114         u8 type;
 115         char *name;
 116         enum {
 117                 RADIUS_ATTR_UNDIST, RADIUS_ATTR_TEXT, RADIUS_ATTR_IP,
 118                 RADIUS_ATTR_HEXDUMP, RADIUS_ATTR_INT32, RADIUS_ATTR_IPV6
 119         } data_type;
 120 };
 121
 122 static struct radius_attr_type radius_attrs[] =
 123 {
 124         { RADIUS_ATTR_USER_NAME, "User-Name", RADIUS_ATTR_TEXT },
 125         { RADIUS_ATTR_USER_PASSWORD, "User-Password", RADIUS_ATTR_UNDIST },
 126         { RADIUS_ATTR_NAS_IP_ADDRESS, "NAS-IP-Address", RADIUS_ATTR_IP },
 127         { RADIUS_ATTR_NAS_PORT, "NAS-Port", RADIUS_ATTR_INT32 },
 128         { RADIUS_ATTR_FRAMED_MTU, "Framed-MTU", RADIUS_ATTR_INT32 },
 129         { RADIUS_ATTR_STATE, "State", RADIUS_ATTR_UNDIST },
 130         { RADIUS_ATTR_CLASS, "Class", RADIUS_ATTR_UNDIST },
 131         { RADIUS_ATTR_VENDOR_SPECIFIC, "Vendor-Specific", RADIUS_ATTR_UNDIST },
 132         { RADIUS_ATTR_SESSION_TIMEOUT, "Session-Timeout", RADIUS_ATTR_INT32 },
 133         { RADIUS_ATTR_IDLE_TIMEOUT, "Idle-Timeout", RADIUS_ATTR_INT32 },
 134         { RADIUS_ATTR_TERMINATION_ACTION, "Termination-Action",
 135           RADIUS_ATTR_INT32 },
 136         { RADIUS_ATTR_CALLED_STATION_ID, "Called-Station-Id",
 137           RADIUS_ATTR_TEXT },
 138         { RADIUS_ATTR_CALLING_STATION_ID, "Calling-Station-Id",
 139           RADIUS_ATTR_TEXT },
 140         { RADIUS_ATTR_NAS_IDENTIFIER, "NAS-Identifier", RADIUS_ATTR_TEXT },
 141         { RADIUS_ATTR_ACCT_STATUS_TYPE, "Acct-Status-Type",
 142           RADIUS_ATTR_INT32 },
 143         { RADIUS_ATTR_ACCT_DELAY_TIME, "Acct-Delay-Time", RADIUS_ATTR_INT32 },
 144         { RADIUS_ATTR_ACCT_INPUT_OCTETS, "Acct-Input-Octets",
 145           RADIUS_ATTR_INT32 },
 146         { RADIUS_ATTR_ACCT_OUTPUT_OCTETS, "Acct-Output-Octets",
 147           RADIUS_ATTR_INT32 },
 148         { RADIUS_ATTR_ACCT_SESSION_ID, "Acct-Session-Id", RADIUS_ATTR_TEXT },
 149         { RADIUS_ATTR_ACCT_AUTHENTIC, "Acct-Authentic", RADIUS_ATTR_INT32 },
 150         { RADIUS_ATTR_ACCT_SESSION_TIME, "Acct-Session-Time",
 151           RADIUS_ATTR_INT32 },
 152         { RADIUS_ATTR_ACCT_INPUT_PACKETS, "Acct-Input-Packets",
 153           RADIUS_ATTR_INT32 },
 154         { RADIUS_ATTR_ACCT_OUTPUT_PACKETS, "Acct-Output-Packets",
 155           RADIUS_ATTR_INT32 },
 156         { RADIUS_ATTR_ACCT_TERMINATE_CAUSE, "Acct-Terminate-Cause",
 157           RADIUS_ATTR_INT32 },
 158         { RADIUS_ATTR_ACCT_MULTI_SESSION_ID, "Acct-Multi-Session-Id",
 159           RADIUS_ATTR_TEXT },
 160         { RADIUS_ATTR_ACCT_LINK_COUNT, "Acct-Link-Count", RADIUS_ATTR_INT32 },
 161         { RADIUS_ATTR_ACCT_INPUT_GIGAWORDS, "Acct-Input-Gigawords",
 162           RADIUS_ATTR_INT32 },
 163         { RADIUS_ATTR_ACCT_OUTPUT_GIGAWORDS, "Acct-Output-Gigawords",
 164           RADIUS_ATTR_INT32 },
 165         { RADIUS_ATTR_EVENT_TIMESTAMP, "Event-Timestamp",
 166           RADIUS_ATTR_INT32 },
 167         { RADIUS_ATTR_NAS_PORT_TYPE, "NAS-Port-Type", RADIUS_ATTR_INT32 },
 168         { RADIUS_ATTR_TUNNEL_TYPE, "Tunnel-Type", RADIUS_ATTR_HEXDUMP },
 169         { RADIUS_ATTR_TUNNEL_MEDIUM_TYPE, "Tunnel-Medium-Type",
 170           RADIUS_ATTR_HEXDUMP },
 171         { RADIUS_ATTR_CONNECT_INFO, "Connect-Info", RADIUS_ATTR_TEXT },
 172         { RADIUS_ATTR_EAP_MESSAGE, "EAP-Message", RADIUS_ATTR_UNDIST },
 173         { RADIUS_ATTR_MESSAGE_AUTHENTICATOR, "Message-Authenticator",
 174           RADIUS_ATTR_UNDIST },
 175         { RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID, "Tunnel-Private-Group-Id",
 176           RADIUS_ATTR_HEXDUMP },
 177         { RADIUS_ATTR_ACCT_INTERIM_INTERVAL, "Acct-Interim-Interval",
 178           RADIUS_ATTR_INT32 },
 179         { RADIUS_ATTR_NAS_IPV6_ADDRESS, "NAS-IPv6-Address", RADIUS_ATTR_IPV6 },
 180 };
 181 #define RADIUS_ATTRS (sizeof(radius_attrs) / sizeof(radius_attrs[0]))
 182
 183
 184 static struct radius_attr_type *radius_get_attr_type(u8 type)
 185 {
 186         size_t i;
 187
 188         for (i = 0; i < RADIUS_ATTRS; i++) {
 189                 if (type == radius_attrs[i].type)
 190                         return &radius_attrs[i];
 191         }
 192
 193         return NULL;
 194 }
 195
 196
 197 static void print_char(char c)
 198 {
 199         if (c >= 32 && c < 127)
 200                 printf("%c", c);
 201         else
 202                 printf("<%02x>", c);
 203 }
 204
 205
 206 static void radius_msg_dump_attr(struct radius_attr_hdr *hdr)
 207 {
 208         struct radius_attr_type *attr;
 209         int i, len;
 210         unsigned char *pos;
 211
 212         attr = radius_get_attr_type(hdr->type);
 213
 214         printf("   Attribute %d (%s) length=%d\n",
 215                hdr->type, attr ? attr->name : "?Unknown?", hdr->length);
 216
 217         if (attr == NULL)
 218                 return;
 219
 220         len = hdr->length - sizeof(struct radius_attr_hdr);
 221         pos = (unsigned char *) (hdr + 1);
 222
 223         switch (attr->data_type) {
 224         case RADIUS_ATTR_TEXT:
 225                 printf("      Value: '");
 226                 for (i = 0; i < len; i++)
 227                         print_char(pos[i]);
 228                 printf("'\n");
 229                 break;
 230
 231         case RADIUS_ATTR_IP:
 232                 if (len == 4) {
 233                         struct in_addr *addr = (struct in_addr *) pos;
 234                         printf("      Value: %s\n", inet_ntoa(*addr));
 235                 } else
 236                         printf("      Invalid IP address length %d\n", len);
 237                 break;
 238
 239 #ifdef CONFIG_IPV6
 240         case RADIUS_ATTR_IPV6:
 241                 if (len == 16) {
 242                         char buf[128];
 243                         const char *atxt;
 244                         struct in6_addr *addr = (struct in6_addr *) pos;
 245                         atxt = inet_ntop(AF_INET6, addr, buf, sizeof(buf));
 246                         printf("      Value: %s\n", atxt ? atxt : "?");
 247                 } else
 248                         printf("      Invalid IPv6 address length %d\n", len);
 249                 break;
 250 #endif /* CONFIG_IPV6 */
 251
 252         case RADIUS_ATTR_HEXDUMP:
 253         case RADIUS_ATTR_UNDIST:
 254                 printf("      Value:");
 255                 for (i = 0; i < len; i++)
 256                         printf(" %02x", pos[i]);
 257                 printf("\n");
 258                 break;
 259
 260         case RADIUS_ATTR_INT32:
 261                 if (len == 4)
 262                         printf("      Value: %u\n", WPA_GET_BE32(pos));
 263                 else
 264                         printf("      Invalid INT32 length %d\n", len);
 265                 break;
 266
 267         default:
 268                 break;
 269         }
 270 }
 271
 272
 273 void radius_msg_dump(struct radius_msg *msg)
 274 {
 275         size_t i;
 276
 277         printf("RADIUS message: code=%d (%s) identifier=%d length=%d\n",
 278                msg->hdr->code, radius_code_string(msg->hdr->code),
 279                msg->hdr->identifier, ntohs(msg->hdr->length));
 280
 281         for (i = 0; i < msg->attr_used; i++) {
 282                 radius_msg_dump_attr(msg->attrs[i]);
 283         }
 284 }
 285
 286
 287 int radius_msg_finish(struct radius_msg *msg, u8 *secret, size_t secret_len)
 288 {
 289         if (secret) {
 290                 u8 auth[MD5_MAC_LEN];
 291                 struct radius_attr_hdr *attr;
 292
 293                 os_memset(auth, 0, MD5_MAC_LEN);
 294                 attr = radius_msg_add_attr(msg,
 295                                            RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
 296                                            auth, MD5_MAC_LEN);
 297                 if (attr == NULL) {
 298                         printf("WARNING: Could not add "
 299                                "Message-Authenticator\n");
 300                         return -1;
 301                 }
 302                 msg->hdr->length = htons(msg->buf_used);
 303                 hmac_md5(secret, secret_len, msg->buf, msg->buf_used,
 304                          (u8 *) (attr + 1));
 305         } else
 306                 msg->hdr->length = htons(msg->buf_used);
 307
 308         if (msg->buf_used > 0xffff) {
 309                 printf("WARNING: too long RADIUS message (%lu)\n",
 310                        (unsigned long) msg->buf_used);
 311                 return -1;
 312         }
 313         return 0;
 314 }
 315
 316
 317 int radius_msg_finish_srv(struct radius_msg *msg, const u8 *secret,
 318                           size_t secret_len, const u8 *req_authenticator)
 319 {
 320         u8 auth[MD5_MAC_LEN];
 321         struct radius_attr_hdr *attr;
 322         const u8 *addr[4];
 323         size_t len[4];
 324
 325         os_memset(auth, 0, MD5_MAC_LEN);
 326         attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
 327                                    auth, MD5_MAC_LEN);
 328         if (attr == NULL) {
 329                 printf("WARNING: Could not add Message-Authenticator\n");
 330                 return -1;
 331         }
 332         msg->hdr->length = htons(msg->buf_used);
 333         os_memcpy(msg->hdr->authenticator, req_authenticator,
 334                   sizeof(msg->hdr->authenticator));
 335         hmac_md5(secret, secret_len, msg->buf, msg->buf_used,
 336                  (u8 *) (attr + 1));
 337
 338         /* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
 339         addr[0] = (u8 *) msg->hdr;
 340         len[0] = 1 + 1 + 2;
 341         addr[1] = req_authenticator;
 342         len[1] = MD5_MAC_LEN;
 343         addr[2] = (u8 *) (msg->hdr + 1);
 344         len[2] = msg->buf_used - sizeof(*msg->hdr);
 345         addr[3] = secret;
 346         len[3] = secret_len;
 347         md5_vector(4, addr, len, msg->hdr->authenticator);
 348
 349         if (msg->buf_used > 0xffff) {
 350                 printf("WARNING: too long RADIUS message (%lu)\n",
 351                        (unsigned long) msg->buf_used);
 352                 return -1;
 353         }
 354         return 0;
 355 }
 356
 357
 358 void radius_msg_finish_acct(struct radius_msg *msg, u8 *secret,
 359                             size_t secret_len)
 360 {
 361         const u8 *addr[2];
 362         size_t len[2];
 363
 364         msg->hdr->length = htons(msg->buf_used);
 365         os_memset(msg->hdr->authenticator, 0, MD5_MAC_LEN);
 366         addr[0] = msg->buf;
 367         len[0] = msg->buf_used;
 368         addr[1] = secret;
 369         len[1] = secret_len;
 370         md5_vector(2, addr, len, msg->hdr->authenticator);
 371
 372         if (msg->buf_used > 0xffff) {
 373                 printf("WARNING: too long RADIUS messages (%lu)\n",
 374                        (unsigned long) msg->buf_used);
 375         }
 376 }
 377
 378
 379 static int radius_msg_add_attr_to_array(struct radius_msg *msg,
 380                                         struct radius_attr_hdr *attr)
 381 {
 382         if (msg->attr_used >= msg->attr_size) {
 383                 struct radius_attr_hdr **nattrs;
 384                 int nlen = msg->attr_size * 2;
 385
 386                 nattrs = os_realloc(msg->attrs, nlen * sizeof(*msg->attrs));
 387                 if (nattrs == NULL)
 388                         return -1;
 389
 390                 msg->attrs = nattrs;
 391                 msg->attr_size = nlen;
 392         }
 393
 394         msg->attrs[msg->attr_used++] = attr;
 395
 396         return 0;
 397 }
 398
 399
 400 struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type,
 401                                             const u8 *data, size_t data_len)
 402 {
 403         size_t buf_needed;
 404         struct radius_attr_hdr *attr;
 405
 406         if (data_len > RADIUS_MAX_ATTR_LEN) {
 407                 printf("radius_msg_add_attr: too long attribute (%lu bytes)\n",
 408                        (unsigned long) data_len);
 409                 return NULL;
 410         }
 411
 412         buf_needed = msg->buf_used + sizeof(*attr) + data_len;
 413
 414         if (msg->buf_size < buf_needed) {
 415                 /* allocate more space for message buffer */
 416                 unsigned char *nbuf;
 417                 size_t i, nlen = msg->buf_size;
 418                 int diff;
 419
 420                 while (nlen < buf_needed)
 421                         nlen *= 2;
 422                 nbuf = os_realloc(msg->buf, nlen);
 423                 if (nbuf == NULL)
 424                         return NULL;
 425                 diff = nbuf - msg->buf;
 426                 msg->buf = nbuf;
 427                 msg->hdr = (struct radius_hdr *) msg->buf;
 428                 /* adjust attr pointers to match with the new buffer */
 429                 for (i = 0; i < msg->attr_used; i++)
 430                         msg->attrs[i] = (struct radius_attr_hdr *)
 431                                 (((u8 *) msg->attrs[i]) + diff);
 432                 os_memset(msg->buf + msg->buf_size, 0, nlen - msg->buf_size);
 433                 msg->buf_size = nlen;
 434         }
 435
 436         attr = (struct radius_attr_hdr *) (msg->buf + msg->buf_used);
 437         attr->type = type;
 438         attr->length = sizeof(*attr) + data_len;
 439         if (data_len > 0)
 440                 os_memcpy(attr + 1, data, data_len);
 441
 442         msg->buf_used += sizeof(*attr) + data_len;
 443
 444         if (radius_msg_add_attr_to_array(msg, attr))
 445                 return NULL;
 446
 447         return attr;
 448 }
 449
 450
 451 struct radius_msg *radius_msg_parse(const u8 *data, size_t len)
 452 {
 453         struct radius_msg *msg;
 454         struct radius_hdr *hdr;
 455         struct radius_attr_hdr *attr;
 456         size_t msg_len;
 457         unsigned char *pos, *end;
 458
 459         if (data == NULL || len < sizeof(*hdr))
 460                 return NULL;
 461
 462         hdr = (struct radius_hdr *) data;
 463
 464         msg_len = ntohs(hdr->length);
 465         if (msg_len < sizeof(*hdr) || msg_len > len) {
 466                 printf("Invalid RADIUS message length\n");
 467                 return NULL;
 468         }
 469
 470         if (msg_len < len) {
 471                 printf("Ignored %lu extra bytes after RADIUS message\n",
 472                        (unsigned long) len - msg_len);
 473         }
 474
 475         msg = os_malloc(sizeof(*msg));
 476         if (msg == NULL)
 477                 return NULL;
 478
 479         if (radius_msg_initialize(msg, msg_len)) {
 480                 os_free(msg);
 481                 return NULL;
 482         }
 483
 484         os_memcpy(msg->buf, data, msg_len);
 485         msg->buf_size = msg->buf_used = msg_len;
 486
 487         /* parse attributes */
 488         pos = (unsigned char *) (msg->hdr + 1);
 489         end = msg->buf + msg->buf_used;
 490         while (pos < end) {
 491                 if ((size_t) (end - pos) < sizeof(*attr))
 492                         goto fail;
 493
 494                 attr = (struct radius_attr_hdr *) pos;
 495
 496                 if (pos + attr->length > end || attr->length < sizeof(*attr))
 497                         goto fail;
 498
 499                 /* TODO: check that attr->length is suitable for attr->type */
 500
 501                 if (radius_msg_add_attr_to_array(msg, attr))
 502                         goto fail;
 503
 504                 pos += attr->length;
 505         }
 506
 507         return msg;
 508
 509  fail:
 510         radius_msg_free(msg);
 511         os_free(msg);
 512         return NULL;
 513 }
 514
 515
 516 int radius_msg_add_eap(struct radius_msg *msg, const u8 *data, size_t data_len)
 517 {
 518         const u8 *pos = data;
 519         size_t left = data_len;
 520
 521         while (left > 0) {
 522                 int len;
 523                 if (left > RADIUS_MAX_ATTR_LEN)
 524                         len = RADIUS_MAX_ATTR_LEN;
 525                 else
 526                         len = left;
 527
 528                 if (!radius_msg_add_attr(msg, RADIUS_ATTR_EAP_MESSAGE,
 529                                          pos, len))
 530                         return 0;
 531
 532                 pos += len;
 533                 left -= len;
 534         }
 535
 536         return 1;
 537 }
 538
 539
 540 u8 *radius_msg_get_eap(struct radius_msg *msg, size_t *eap_len)
 541 {
 542         u8 *eap, *pos;
 543         size_t len, i;
 544
 545         if (msg == NULL)
 546                 return NULL;
 547
 548         len = 0;
 549         for (i = 0; i < msg->attr_used; i++) {
 550                 if (msg->attrs[i]->type == RADIUS_ATTR_EAP_MESSAGE)
 551                         len += msg->attrs[i]->length -
 552                                 sizeof(struct radius_attr_hdr);
 553         }
 554
 555         if (len == 0)
 556                 return NULL;
 557
 558         eap = os_malloc(len);
 559         if (eap == NULL)
 560                 return NULL;
 561
 562         pos = eap;
 563         for (i = 0; i < msg->attr_used; i++) {
 564                 if (msg->attrs[i]->type == RADIUS_ATTR_EAP_MESSAGE) {
 565                         struct radius_attr_hdr *attr = msg->attrs[i];
 566                         int flen = attr->length - sizeof(*attr);
 567                         os_memcpy(pos, attr + 1, flen);
 568                         pos += flen;
 569                 }
 570         }
 571
 572         if (eap_len)
 573                 *eap_len = len;
 574
 575         return eap;
 576 }
 577
 578
 579 int radius_msg_verify_msg_auth(struct radius_msg *msg, const u8 *secret,
 580                                size_t secret_len, const u8 *req_auth)
 581 {
 582         u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
 583         u8 orig_authenticator[16];
 584         struct radius_attr_hdr *attr = NULL;
 585         size_t i;
 586
 587         for (i = 0; i < msg->attr_used; i++) {
 588                 if (msg->attrs[i]->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
 589                         if (attr != NULL) {
 590                                 printf("Multiple Message-Authenticator "
 591                                        "attributes in RADIUS message\n");
 592                                 return 1;
 593                         }
 594                         attr = msg->attrs[i];
 595                 }
 596         }
 597
 598         if (attr == NULL) {
 599                 printf("No Message-Authenticator attribute found\n");
 600                 return 1;
 601         }
 602
 603         os_memcpy(orig, attr + 1, MD5_MAC_LEN);
 604         os_memset(attr + 1, 0, MD5_MAC_LEN);
 605         if (req_auth) {
 606                 os_memcpy(orig_authenticator, msg->hdr->authenticator,
 607                           sizeof(orig_authenticator));
 608                 os_memcpy(msg->hdr->authenticator, req_auth,
 609                           sizeof(msg->hdr->authenticator));
 610         }
 611         hmac_md5(secret, secret_len, msg->buf, msg->buf_used, auth);
 612         os_memcpy(attr + 1, orig, MD5_MAC_LEN);
 613         if (req_auth) {
 614                 os_memcpy(msg->hdr->authenticator, orig_authenticator,
 615                           sizeof(orig_authenticator));
 616         }
 617
 618         if (os_memcmp(orig, auth, MD5_MAC_LEN) != 0) {
 619                 printf("Invalid Message-Authenticator!\n");
 620                 return 1;
 621         }
 622
 623         return 0;
 624 }
 625
 626
 627 int radius_msg_verify(struct radius_msg *msg, const u8 *secret,
 628                       size_t secret_len, struct radius_msg *sent_msg, int auth)
 629 {
 630         const u8 *addr[4];
 631         size_t len[4];
 632         u8 hash[MD5_MAC_LEN];
 633
 634         if (sent_msg == NULL) {
 635                 printf("No matching Access-Request message found\n");
 636                 return 1;
 637         }
 638
 639         if (auth &&
 640             radius_msg_verify_msg_auth(msg, secret, secret_len,
 641                                        sent_msg->hdr->authenticator)) {
 642                 return 1;
 643         }
 644
 645         /* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
 646         addr[0] = (u8 *) msg->hdr;
 647         len[0] = 1 + 1 + 2;
 648         addr[1] = sent_msg->hdr->authenticator;
 649         len[1] = MD5_MAC_LEN;
 650         addr[2] = (u8 *) (msg->hdr + 1);
 651         len[2] = msg->buf_used - sizeof(*msg->hdr);
 652         addr[3] = secret;
 653         len[3] = secret_len;
 654         md5_vector(4, addr, len, hash);
 655         if (os_memcmp(hash, msg->hdr->authenticator, MD5_MAC_LEN) != 0) {
 656                 printf("Response Authenticator invalid!\n");
 657                 return 1;
 658         }
 659
 660         return 0;
 661 }
 662
 663
 664 int radius_msg_copy_attr(struct radius_msg *dst, struct radius_msg *src,
 665                          u8 type)
 666 {
 667         struct radius_attr_hdr *attr = NULL;
 668         size_t i;
 669
 670         for (i = 0; i < src->attr_used; i++) {
 671                 if (src->attrs[i]->type == type) {
 672                         attr = src->attrs[i];
 673                         break;
 674                 }
 675         }
 676
 677         if (attr == NULL)
 678                 return 0;
 679
 680         if (!radius_msg_add_attr(dst, type, (u8 *) (attr + 1),
 681                                  attr->length - sizeof(*attr)))
 682                 return -1;
 683
 684         return 1;
 685 }
 686
 687
 688 /* Create Request Authenticator. The value should be unique over the lifetime
 689  * of the shared secret between authenticator and authentication server.
 690  * Use one-way MD5 hash calculated from current timestamp and some data given
 691  * by the caller. */
 692 void radius_msg_make_authenticator(struct radius_msg *msg,
 693                                    const u8 *data, size_t len)
 694 {
 695         struct os_time tv;
 696         long int l;
 697         const u8 *addr[3];
 698         size_t elen[3];
 699
 700         os_get_time(&tv);
 701         l = os_random();
 702         addr[0] = (u8 *) &tv;
 703         elen[0] = sizeof(tv);
 704         addr[1] = data;
 705         elen[1] = len;
 706         addr[2] = (u8 *) &l;
 707         elen[2] = sizeof(l);
 708         md5_vector(3, addr, elen, msg->hdr->authenticator);
 709 }
 710
 711
 712 /* Get Vendor-specific RADIUS Attribute from a parsed RADIUS message.
 713  * Returns the Attribute payload and sets alen to indicate the length of the
 714  * payload if a vendor attribute with subtype is found, otherwise returns NULL.
 715  * The returned payload is allocated with os_malloc() and caller must free it
 716  * by calling os_free().
 717  */
 718 static u8 *radius_msg_get_vendor_attr(struct radius_msg *msg, u32 vendor,
 719                                       u8 subtype, size_t *alen)
 720 {
 721         u8 *data, *pos;
 722         size_t i, len;
 723
 724         if (msg == NULL)
 725                 return NULL;
 726
 727         for (i = 0; i < msg->attr_used; i++) {
 728                 struct radius_attr_hdr *attr = msg->attrs[i];
 729                 size_t left;
 730                 u32 vendor_id;
 731                 struct radius_attr_vendor *vhdr;
 732
 733                 if (attr->type != RADIUS_ATTR_VENDOR_SPECIFIC)
 734                         continue;
 735
 736                 left = attr->length - sizeof(*attr);
 737                 if (left < 4)
 738                         continue;
 739
 740                 pos = (u8 *) (attr + 1);
 741
 742                 os_memcpy(&vendor_id, pos, 4);
 743                 pos += 4;
 744                 left -= 4;
 745
 746                 if (ntohl(vendor_id) != vendor)
 747                         continue;
 748
 749                 while (left >= sizeof(*vhdr)) {
 750                         vhdr = (struct radius_attr_vendor *) pos;
 751                         if (vhdr->vendor_length > left ||
 752                             vhdr->vendor_length < sizeof(*vhdr)) {
 753                                 left = 0;
 754                                 break;
 755                         }
 756                         if (vhdr->vendor_type != subtype) {
 757                                 pos += vhdr->vendor_length;
 758                                 left -= vhdr->vendor_length;
 759                                 continue;
 760                         }
 761
 762                         len = vhdr->vendor_length - sizeof(*vhdr);
 763                         data = os_malloc(len);
 764                         if (data == NULL)
 765                                 return NULL;
 766                         os_memcpy(data, pos + sizeof(*vhdr), len);
 767                         if (alen)
 768                                 *alen = len;
 769                         return data;
 770                 }
 771         }
 772
 773         return NULL;
 774 }
 775
 776
 777 static u8 * decrypt_ms_key(const u8 *key, size_t len,
 778                            const u8 *req_authenticator,
 779                            const u8 *secret, size_t secret_len, size_t *reslen)
 780 {
 781         u8 *plain, *ppos, *res;
 782         const u8 *pos;
 783         size_t left, plen;
 784         u8 hash[MD5_MAC_LEN];
 785         int i, first = 1;
 786         const u8 *addr[3];
 787         size_t elen[3];
 788
 789         /* key: 16-bit salt followed by encrypted key info */
 790
 791         if (len < 2 + 16)
 792                 return NULL;
 793
 794         pos = key + 2;
 795         left = len - 2;
 796         if (left % 16) {
 797                 printf("Invalid ms key len %lu\n", (unsigned long) left);
 798                 return NULL;
 799         }
 800
 801         plen = left;
 802         ppos = plain = os_malloc(plen);
 803         if (plain == NULL)
 804                 return NULL;
 805
 806         while (left > 0) {
 807                 /* b(1) = MD5(Secret + Request-Authenticator + Salt)
 808                  * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
 809
 810                 addr[0] = secret;
 811                 elen[0] = secret_len;
 812                 if (first) {
 813                         addr[1] = req_authenticator;
 814                         elen[1] = MD5_MAC_LEN;
 815                         addr[2] = key;
 816                         elen[2] = 2; /* Salt */
 817                 } else {
 818                         addr[1] = pos - MD5_MAC_LEN;
 819                         elen[1] = MD5_MAC_LEN;
 820                 }
 821                 md5_vector(first ? 3 : 2, addr, elen, hash);
 822                 first = 0;
 823
 824                 for (i = 0; i < MD5_MAC_LEN; i++)
 825                         *ppos++ = *pos++ ^ hash[i];
 826                 left -= MD5_MAC_LEN;
 827         }
 828
 829         if (plain[0] > plen - 1) {
 830                 printf("Failed to decrypt MPPE key\n");
 831                 os_free(plain);
 832                 return NULL;
 833         }
 834
 835         res = os_malloc(plain[0]);
 836         if (res == NULL) {
 837                 os_free(plain);
 838                 return NULL;
 839         }
 840         os_memcpy(res, plain + 1, plain[0]);
 841         if (reslen)
 842                 *reslen = plain[0];
 843         os_free(plain);
 844         return res;
 845 }
 846
 847
 848 static void encrypt_ms_key(const u8 *key, size_t key_len, u16 salt,
 849                            const u8 *req_authenticator,
 850                            const u8 *secret, size_t secret_len,
 851                            u8 *ebuf, size_t *elen)
 852 {
 853         int i, len, first = 1;
 854         u8 hash[MD5_MAC_LEN], saltbuf[2], *pos;
 855         const u8 *addr[3];
 856         size_t _len[3];
 857
 858         saltbuf[0] = salt >> 8;
 859         saltbuf[1] = salt;
 860
 861         len = 1 + key_len;
 862         if (len & 0x0f) {
 863                 len = (len & 0xf0) + 16;
 864         }
 865         os_memset(ebuf, 0, len);
 866         ebuf[0] = key_len;
 867         os_memcpy(ebuf + 1, key, key_len);
 868
 869         *elen = len;
 870
 871         pos = ebuf;
 872         while (len > 0) {
 873                 /* b(1) = MD5(Secret + Request-Authenticator + Salt)
 874                  * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
 875                 addr[0] = secret;
 876                 _len[0] = secret_len;
 877                 if (first) {
 878                         addr[1] = req_authenticator;
 879                         _len[1] = MD5_MAC_LEN;
 880                         addr[2] = saltbuf;
 881                         _len[2] = sizeof(saltbuf);
 882                 } else {
 883                         addr[1] = pos - MD5_MAC_LEN;
 884                         _len[1] = MD5_MAC_LEN;
 885                 }
 886                 md5_vector(first ? 3 : 2, addr, _len, hash);
 887                 first = 0;
 888
 889                 for (i = 0; i < MD5_MAC_LEN; i++)
 890                         *pos++ ^= hash[i];
 891
 892                 len -= MD5_MAC_LEN;
 893         }
 894 }
 895
 896
 897 struct radius_ms_mppe_keys *
 898 radius_msg_get_ms_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
 899                        u8 *secret, size_t secret_len)
 900 {
 901         u8 *key;
 902         size_t keylen;
 903         struct radius_ms_mppe_keys *keys;
 904
 905         if (msg == NULL || sent_msg == NULL)
 906                 return NULL;
 907
 908         keys = wpa_zalloc(sizeof(*keys));
 909         if (keys == NULL)
 910                 return NULL;
 911
 912         key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
 913                                          RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY,
 914                                          &keylen);
 915         if (key) {
 916                 keys->send = decrypt_ms_key(key, keylen,
 917                                             sent_msg->hdr->authenticator,
 918                                             secret, secret_len,
 919                                             &keys->send_len);
 920                 os_free(key);
 921         }
 922
 923         key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
 924                                          RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY,
 925                                          &keylen);
 926         if (key) {
 927                 keys->recv = decrypt_ms_key(key, keylen,
 928                                             sent_msg->hdr->authenticator,
 929                                             secret, secret_len,
 930                                             &keys->recv_len);
 931                 os_free(key);
 932         }
 933
 934         return keys;
 935 }
 936
 937
 938 struct radius_ms_mppe_keys *
 939 radius_msg_get_cisco_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
 940                           u8 *secret, size_t secret_len)
 941 {
 942         u8 *key;
 943         size_t keylen;
 944         struct radius_ms_mppe_keys *keys;
 945
 946         if (msg == NULL || sent_msg == NULL)
 947                 return NULL;
 948
 949         keys = wpa_zalloc(sizeof(*keys));
 950         if (keys == NULL)
 951                 return NULL;
 952
 953         key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_CISCO,
 954                                          RADIUS_CISCO_AV_PAIR, &keylen);
 955         if (key && keylen == 51 &&
 956             os_memcmp(key, "leap:session-key=", 17) == 0) {
 957                 keys->recv = decrypt_ms_key(key + 17, keylen - 17,
 958                                             sent_msg->hdr->authenticator,
 959                                             secret, secret_len,
 960                                             &keys->recv_len);
 961         }
 962         os_free(key);
 963
 964         return keys;
 965 }
 966
 967
 968 int radius_msg_add_mppe_keys(struct radius_msg *msg,
 969                              const u8 *req_authenticator,
 970                              const u8 *secret, size_t secret_len,
 971                              const u8 *send_key, size_t send_key_len,
 972                              const u8 *recv_key, size_t recv_key_len)
 973 {
 974         struct radius_attr_hdr *attr;
 975         u32 vendor_id = htonl(RADIUS_VENDOR_ID_MICROSOFT);
 976         u8 *buf;
 977         struct radius_attr_vendor *vhdr;
 978         u8 *pos;
 979         size_t elen;
 980         int hlen;
 981         u16 salt;
 982
 983         hlen = sizeof(vendor_id) + sizeof(*vhdr) + 2;
 984
 985         /* MS-MPPE-Send-Key */
 986         buf = os_malloc(hlen + send_key_len + 16);
 987         if (buf == NULL) {
 988                 return 0;
 989         }
 990         pos = buf;
 991         os_memcpy(pos, &vendor_id, sizeof(vendor_id));
 992         pos += sizeof(vendor_id);
 993         vhdr = (struct radius_attr_vendor *) pos;
 994         vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY;
 995         pos = (u8 *) (vhdr + 1);
 996         salt = os_random() | 0x8000;
 997         *pos++ = salt >> 8;
 998         *pos++ = salt;
 999         encrypt_ms_key(send_key, send_key_len, salt, req_authenticator, secret,
1000                        secret_len, pos, &elen);
1001         vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1002
1003         attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1004                                    buf, hlen + elen);
1005         os_free(buf);
1006         if (attr == NULL) {
1007                 return 0;
1008         }
1009
1010         /* MS-MPPE-Recv-Key */
1011         buf = os_malloc(hlen + send_key_len + 16);
1012         if (buf == NULL) {
1013                 return 0;
1014         }
1015         pos = buf;
1016         os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1017         pos += sizeof(vendor_id);
1018         vhdr = (struct radius_attr_vendor *) pos;
1019         vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY;
1020         pos = (u8 *) (vhdr + 1);
1021         salt ^= 1;
1022         *pos++ = salt >> 8;
1023         *pos++ = salt;
1024         encrypt_ms_key(recv_key, recv_key_len, salt, req_authenticator, secret,
1025                        secret_len, pos, &elen);
1026         vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1027
1028         attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1029                                    buf, hlen + elen);
1030         os_free(buf);
1031         if (attr == NULL) {
1032                 return 0;
1033         }
1034
1035         return 1;
1036 }
1037
1038
1039 /* Add User-Password attribute to a RADIUS message and encrypt it as specified
1040  * in RFC 2865, Chap. 5.2 */
1041 struct radius_attr_hdr *
1042 radius_msg_add_attr_user_password(struct radius_msg *msg,
1043                                   u8 *data, size_t data_len,
1044                                   u8 *secret, size_t secret_len)
1045 {
1046         u8 buf[128];
1047         int padlen, i;
1048         size_t buf_len, pos;
1049         const u8 *addr[2];
1050         size_t len[2];
1051         u8 hash[16];
1052
1053         if (data_len > 128)
1054                 return NULL;
1055
1056         os_memcpy(buf, data, data_len);
1057         buf_len = data_len;
1058
1059         padlen = data_len % 16;
1060         if (padlen) {
1061                 padlen = 16 - padlen;
1062                 os_memset(buf + data_len, 0, padlen);
1063                 buf_len += padlen;
1064         }
1065
1066         addr[0] = secret;
1067         len[0] = secret_len;
1068         addr[1] = msg->hdr->authenticator;
1069         len[1] = 16;
1070         md5_vector(2, addr, len, hash);
1071
1072         for (i = 0; i < 16; i++)
1073                 buf[i] ^= hash[i];
1074         pos = 16;
1075
1076         while (pos < buf_len) {
1077                 addr[0] = secret;
1078                 len[0] = secret_len;
1079                 addr[1] = &buf[pos - 16];
1080                 len[1] = 16;
1081                 md5_vector(2, addr, len, hash);
1082
1083                 for (i = 0; i < 16; i++)
1084                         buf[pos + i] ^= hash[i];
1085
1086                 pos += 16;
1087         }
1088
1089         return radius_msg_add_attr(msg, RADIUS_ATTR_USER_PASSWORD,
1090                                    buf, buf_len);
1091 }
1092
1093
1094 int radius_msg_get_attr(struct radius_msg *msg, u8 type, u8 *buf, size_t len)
1095 {
1096         struct radius_attr_hdr *attr = NULL;
1097         size_t i, dlen;
1098
1099         for (i = 0; i < msg->attr_used; i++) {
1100                 if (msg->attrs[i]->type == type) {
1101                         attr = msg->attrs[i];
1102                         break;
1103                 }
1104         }
1105
1106         if (!attr)
1107                 return -1;
1108
1109         dlen = attr->length - sizeof(*attr);
1110         if (buf)
1111                 os_memcpy(buf, (attr + 1), dlen > len ? len : dlen);
1112         return dlen;
1113 }
1114
1115
1116 int radius_msg_get_attr_ptr(struct radius_msg *msg, u8 type, u8 **buf,
1117                             size_t *len, const u8 *start)
1118 {
1119         size_t i;
1120         struct radius_attr_hdr *attr = NULL;
1121
1122         for (i = 0; i < msg->attr_used; i++) {
1123                 if (msg->attrs[i]->type == type &&
1124                     (start == NULL || (u8 *) msg->attrs[i] > start)) {
1125                         attr = msg->attrs[i];
1126                         break;
1127                 }
1128         }
1129
1130         if (!attr)
1131                 return -1;
1132
1133         *buf = (u8 *) (attr + 1);
1134         *len = attr->length - sizeof(*attr);
1135         return 0;
1136 }
1137
1138
1139 int radius_msg_count_attr(struct radius_msg *msg, u8 type, int min_len)
1140 {
1141         size_t i;
1142         int count;
1143
1144         for (count = 0, i = 0; i < msg->attr_used; i++) {
1145                 if (msg->attrs[i]->type == type &&
1146                     msg->attrs[i]->length >=
1147                     sizeof(struct radius_attr_hdr) + min_len)
1148                         count++;
1149         }
1150
1151         return count;
1152 }
1153
1154
1155 struct radius_tunnel_attrs {
1156         int tag_used;
1157         int type; /* Tunnel-Type */
1158         int medium_type; /* Tunnel-Medium-Type */
1159         int vlanid;
1160 };
1161
1162
1163 /**
1164  * radius_msg_get_vlanid - Parse RADIUS attributes for VLAN tunnel information
1165  * @msg: RADIUS message
1166  * Returns: VLAN ID for the first tunnel configuration of -1 if none is found
1167  */
1168 int radius_msg_get_vlanid(struct radius_msg *msg)
1169 {
1170         struct radius_tunnel_attrs tunnel[RADIUS_TUNNEL_TAGS], *tun;
1171         size_t i;
1172         struct radius_attr_hdr *attr = NULL;
1173         const u8 *data;
1174         char buf[10];
1175         size_t dlen;
1176
1177         os_memset(&tunnel, 0, sizeof(tunnel));
1178
1179         for (i = 0; i < msg->attr_used; i++) {
1180                 attr = msg->attrs[i];
1181                 data = (const u8 *) (attr + 1);
1182                 dlen = attr->length - sizeof(*attr);
1183                 if (attr->length < 3)
1184                         continue;
1185                 if (data[0] >= RADIUS_TUNNEL_TAGS)
1186                         tun = &tunnel[0];
1187                 else
1188                         tun = &tunnel[data[0]];
1189
1190                 switch (attr->type) {
1191                 case RADIUS_ATTR_TUNNEL_TYPE:
1192                         if (attr->length != 6)
1193                                 break;
1194                         tun->tag_used++;
1195                         tun->type = (data[1] << 16) | (data[2] << 8) | data[3];
1196                         break;
1197                 case RADIUS_ATTR_TUNNEL_MEDIUM_TYPE:
1198                         if (attr->length != 6)
1199                                 break;
1200                         tun->tag_used++;
1201                         tun->medium_type =
1202                                 (data[1] << 16) | (data[2] << 8) | data[3];
1203                         break;
1204                 case RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID:
1205                         if (data[0] < RADIUS_TUNNEL_TAGS) {
1206                                 data++;
1207                                 dlen--;
1208                         }
1209                         if (dlen >= sizeof(buf))
1210                                 break;
1211                         os_memcpy(buf, data, dlen);
1212                         buf[dlen] = '\0';
1213                         tun->tag_used++;
1214                         tun->vlanid = atoi(buf);
1215                         break;
1216                 }
1217         }
1218
1219         for (i = 0; i < RADIUS_TUNNEL_TAGS; i++) {
1220                 tun = &tunnel[i];
1221                 if (tun->tag_used &&
1222                     tun->type == RADIUS_TUNNEL_TYPE_VLAN &&
1223                     tun->medium_type == RADIUS_TUNNEL_MEDIUM_TYPE_802 &&
1224                     tun->vlanid > 0)
1225                         return tun->vlanid;
1226         }
1227
1228         return -1;
1229 }