src/lib/radius.c

   1 /*
   2  * radius.c     Functions to send/receive radius packets.
   3  *
   4  * Version:     $Id$
   5  *
   6  *   This library is free software; you can redistribute it and/or
   7  *   modify it under the terms of the GNU Lesser General Public
   8  *   License as published by the Free Software Foundation; either
   9  *   version 2.1 of the License, or (at your option) any later version.
  10  *
  11  *   This library is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  *   Lesser General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU Lesser General Public
  17  *   License along with this library; if not, write to the Free Software
  18  *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  * Copyright 2000-2003,2006  The FreeRADIUS server project
  21  */
  22
  23 #include        <freeradius-devel/ident.h>
  24 RCSID("$Id$")
  25
  26 #include        <freeradius-devel/libradius.h>
  27 #include        <freeradius-devel/md5.h>
  28
  29 #include        <fcntl.h>
  30 #include        <ctype.h>
  31
  32 #ifdef WITH_UDPFROMTO
  33 #include        <freeradius-devel/udpfromto.h>
  34 #endif
  35
  36 #ifdef HAVE_MALLOC_H
  37 #include        <malloc.h>
  38 #endif
  39
  40 /*
  41  *  The RFC says 4096 octets max, and most packets are less than 256.
  42  */
  43 #define MAX_PACKET_LEN 4096
  44
  45 /*
  46  *      The maximum number of attributes which we allow in an incoming
  47  *      request.  If there are more attributes than this, the request
  48  *      is rejected.
  49  *
  50  *      This helps to minimize the potential for a DoS, when an
  51  *      attacker spoofs Access-Request packets, which don't have a
  52  *      Message-Authenticator attribute.  This means that the packet
  53  *      is unsigned, and the attacker can use resources on the server,
  54  *      even if the end request is rejected.
  55  */
  56 int fr_max_attributes = 0;
  57 FILE *fr_log_fp = NULL;
  58
  59 typedef struct radius_packet_t {
  60   uint8_t       code;
  61   uint8_t       id;
  62   uint8_t       length[2];
  63   uint8_t       vector[AUTH_VECTOR_LEN];
  64   uint8_t       data[1];
  65 } radius_packet_t;
  66
  67 static fr_randctx fr_rand_pool; /* across multiple calls */
  68 static int fr_rand_initialized = 0;
  69 static unsigned int salt_offset = 0;
  70
  71 const char *fr_packet_codes[FR_MAX_PACKET_CODE] = {
  72   "",
  73   "Access-Request",
  74   "Access-Accept",
  75   "Access-Reject",
  76   "Accounting-Request",
  77   "Accounting-Response",
  78   "Accounting-Status",
  79   "Password-Request",
  80   "Password-Accept",
  81   "Password-Reject",
  82   "Accounting-Message",
  83   "Access-Challenge",
  84   "Status-Server",
  85   "Status-Client",
  86   "14",
  87   "15",
  88   "16",
  89   "17",
  90   "18",
  91   "19",
  92   "20",
  93   "Resource-Free-Request",
  94   "Resource-Free-Response",
  95   "Resource-Query-Request",
  96   "Resource-Query-Response",
  97   "Alternate-Resource-Reclaim-Request",
  98   "NAS-Reboot-Request",
  99   "NAS-Reboot-Response",
 100   "28",
 101   "Next-Passcode",
 102   "New-Pin",
 103   "Terminate-Session",
 104   "Password-Expired",
 105   "Event-Request",
 106   "Event-Response",
 107   "35",
 108   "36",
 109   "37",
 110   "38",
 111   "39",
 112   "Disconnect-Request",
 113   "Disconnect-ACK",
 114   "Disconnect-NAK",
 115   "CoA-Request",
 116   "CoA-ACK",
 117   "CoA-NAK",
 118   "46",
 119   "47",
 120   "48",
 121   "49",
 122   "IP-Address-Allocate",
 123   "IP-Address-Release"
 124 };
 125
 126
 127 void fr_printf_log(const char *fmt, ...)
 128 {
 129         va_list ap;
 130
 131         va_start(ap, fmt);
 132         if ((fr_debug_flag == 0) || !fr_log_fp) {
 133                 va_end(ap);
 134                 return;
 135         }
 136
 137         vfprintf(fr_log_fp, fmt, ap);
 138         va_end(ap);
 139
 140         return;
 141 }
 142
 143 static void print_hex(RADIUS_PACKET *packet)
 144 {
 145         int i;
 146
 147         if (!packet->data) return;
 148
 149         printf("  Code:\t\t%u\n", packet->data[0]);
 150         printf("  Id:\t\t%u\n", packet->data[1]);
 151         printf("  Length:\t%u\n", ((packet->data[2] << 8) |
 152                                    (packet->data[3])));
 153         printf("  Vector:\t");
 154         for (i = 4; i < 20; i++) {
 155                 printf("%02x", packet->data[i]);
 156         }
 157         printf("\n");
 158
 159         if (packet->data_len > 20) {
 160                 int total;
 161                 const uint8_t *ptr;
 162                 printf("  Data:");
 163
 164                 total = packet->data_len - 20;
 165                 ptr = packet->data + 20;
 166
 167                 while (total > 0) {
 168                         int attrlen;
 169
 170                         printf("\t\t");
 171                         if (total < 2) { /* too short */
 172                                 printf("%02x\n", *ptr);
 173                                 break;
 174                         }
 175
 176                         if (ptr[1] > total) { /* too long */
 177                                 for (i = 0; i < total; i++) {
 178                                         printf("%02x ", ptr[i]);
 179                                 }
 180                                 break;
 181                         }
 182
 183                         printf("%02x  %02x  ", ptr[0], ptr[1]);
 184                         attrlen = ptr[1] - 2;
 185                         ptr += 2;
 186                         total -= 2;
 187
 188                         for (i = 0; i < attrlen; i++) {
 189                                 if ((i > 0) && ((i & 0x0f) == 0x00))
 190                                         printf("\t\t\t");
 191                                 printf("%02x ", ptr[i]);
 192                                 if ((i & 0x0f) == 0x0f) printf("\n");
 193                         }
 194
 195                         if ((attrlen & 0x0f) != 0x00) printf("\n");
 196
 197                         ptr += attrlen;
 198                         total -= attrlen;
 199                 }
 200         }
 201         fflush(stdout);
 202 }
 203
 204
 205 /*
 206  *      Wrapper for sendto which handles sendfromto, IPv6, and all
 207  *      possible combinations.
 208  */
 209 static int rad_sendto(int sockfd, void *data, size_t data_len, int flags,
 210                       fr_ipaddr_t *src_ipaddr, int src_port,
 211                       fr_ipaddr_t *dst_ipaddr, int dst_port)
 212 {
 213         struct sockaddr_storage dst;
 214         socklen_t               sizeof_dst;
 215
 216 #ifdef WITH_UDPFROMTO
 217         struct sockaddr_storage src;
 218         socklen_t               sizeof_src;
 219
 220         fr_ipaddr2sockaddr(src_ipaddr, src_port, &src, &sizeof_src);
 221 #else
 222         src_port = src_port;    /* -Wunused */
 223 #endif
 224
 225         if (!fr_ipaddr2sockaddr(dst_ipaddr, dst_port, &dst, &sizeof_dst)) {
 226                 return -1;
 227         }
 228
 229 #ifdef WITH_UDPFROMTO
 230         /*
 231          *      Only IPv4 is supported for udpfromto.
 232          *
 233          *      And if they don't specify a source IP address, don't
 234          *      use udpfromto.
 235          */
 236         if ((dst_ipaddr->af == AF_INET) ||
 237             (src_ipaddr->af != AF_UNSPEC)) {
 238                 return sendfromto(sockfd, data, data_len, flags,
 239                                   (struct sockaddr *)&src, sizeof_src,
 240                                   (struct sockaddr *)&dst, sizeof_dst);
 241         }
 242 #else
 243         src_ipaddr = src_ipaddr; /* -Wunused */
 244 #endif
 245
 246         /*
 247          *      No udpfromto, OR an IPv6 socket, fail gracefully.
 248          */
 249         return sendto(sockfd, data, data_len, flags,
 250                       (struct sockaddr *) &dst, sizeof_dst);
 251 }
 252
 253
 254 void rad_recv_discard(int sockfd)
 255 {
 256         uint8_t                 header[4];
 257         struct sockaddr_storage src;
 258         socklen_t               sizeof_src = sizeof(src);
 259
 260         recvfrom(sockfd, header, sizeof(header), 0,
 261                  (struct sockaddr *)&src, &sizeof_src);
 262 }
 263
 264
 265 ssize_t rad_recv_header(int sockfd, fr_ipaddr_t *src_ipaddr, int *src_port,
 266                         int *code)
 267 {
 268         ssize_t                 data_len, packet_len;
 269         uint8_t                 header[4];
 270         struct sockaddr_storage src;
 271         socklen_t               sizeof_src = sizeof(src);
 272
 273         data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
 274                             (struct sockaddr *)&src, &sizeof_src);
 275         if (data_len < 0) {
 276                 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
 277                 return -1;
 278         }
 279
 280         /*
 281          *      Too little data is available, discard the packet.
 282          */
 283         if (data_len < 4) {
 284                 recvfrom(sockfd, header, sizeof(header), 0,
 285                          (struct sockaddr *)&src, &sizeof_src);
 286                 return 1;
 287
 288         } else {                /* we got 4 bytes of data. */
 289                 /*
 290                  *      See how long the packet says it is.
 291                  */
 292                 packet_len = (header[2] * 256) + header[3];
 293
 294                 /*
 295                  *      The length in the packet says it's less than
 296                  *      a RADIUS header length: discard it.
 297                  */
 298                 if (packet_len < AUTH_HDR_LEN) {
 299                         recvfrom(sockfd, header, sizeof(header), 0,
 300                                  (struct sockaddr *)&src, &sizeof_src);
 301                         return 1;
 302
 303                         /*
 304                          *      Enforce RFC requirements, for sanity.
 305                          *      Anything after 4k will be discarded.
 306                          */
 307                 } else if (packet_len > MAX_PACKET_LEN) {
 308                         recvfrom(sockfd, header, sizeof(header), 0,
 309                                  (struct sockaddr *)&src, &sizeof_src);
 310                         return 1;
 311                 }
 312         }
 313
 314         /*
 315          *      Convert AF.  If unknown, discard packet.
 316          */
 317         if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, src_port)) {
 318                 recvfrom(sockfd, header, sizeof(header), 0,
 319                          (struct sockaddr *)&src, &sizeof_src);
 320                 return 1;
 321         }
 322
 323         *code = header[0];
 324
 325         /*
 326          *      The packet says it's this long, but the actual UDP
 327          *      size could still be smaller.
 328          */
 329         return packet_len;
 330 }
 331
 332
 333 /*
 334  *      wrapper for recvfrom, which handles recvfromto, IPv6, and all
 335  *      possible combinations.
 336  */
 337 static ssize_t rad_recvfrom(int sockfd, uint8_t **pbuf, int flags,
 338                             fr_ipaddr_t *src_ipaddr, uint16_t *src_port,
 339                             fr_ipaddr_t *dst_ipaddr, uint16_t *dst_port)
 340 {
 341         struct sockaddr_storage src;
 342         struct sockaddr_storage dst;
 343         socklen_t               sizeof_src = sizeof(src);
 344         socklen_t               sizeof_dst = sizeof(dst);
 345         ssize_t                 data_len;
 346         uint8_t                 header[4];
 347         void                    *buf;
 348         size_t                  len;
 349         int                     port;
 350
 351         memset(&src, 0, sizeof_src);
 352         memset(&dst, 0, sizeof_dst);
 353
 354         /*
 355          *      Get address family, etc. first, so we know if we
 356          *      need to do udpfromto.
 357          *
 358          *      FIXME: udpfromto also does this, but it's not
 359          *      a critical problem.
 360          */
 361         if (getsockname(sockfd, (struct sockaddr *)&dst,
 362                         &sizeof_dst) < 0) return -1;
 363
 364         /*
 365          *      Read the length of the packet, from the packet.
 366          *      This lets us allocate the buffer to use for
 367          *      reading the rest of the packet.
 368          */
 369         data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
 370                             (struct sockaddr *)&src, &sizeof_src);
 371         if (data_len < 0) {
 372                 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
 373                 return -1;
 374         }
 375
 376         /*
 377          *      Too little data is available, discard the packet.
 378          */
 379         if (data_len < 4) {
 380                 recvfrom(sockfd, header, sizeof(header), flags,
 381                          (struct sockaddr *)&src, &sizeof_src);
 382                 return 0;
 383
 384         } else {                /* we got 4 bytes of data. */
 385                 /*
 386                  *      See how long the packet says it is.
 387                  */
 388                 len = (header[2] * 256) + header[3];
 389
 390                 /*
 391                  *      The length in the packet says it's less than
 392                  *      a RADIUS header length: discard it.
 393                  */
 394                 if (len < AUTH_HDR_LEN) {
 395                         recvfrom(sockfd, header, sizeof(header), flags,
 396                                  (struct sockaddr *)&src, &sizeof_src);
 397                         return 0;
 398
 399                         /*
 400                          *      Enforce RFC requirements, for sanity.
 401                          *      Anything after 4k will be discarded.
 402                          */
 403                 } else if (len > MAX_PACKET_LEN) {
 404                         recvfrom(sockfd, header, sizeof(header), flags,
 405                                  (struct sockaddr *)&src, &sizeof_src);
 406                         return len;
 407                 }
 408         }
 409
 410         buf = malloc(len);
 411         if (!buf) return -1;
 412
 413         /*
 414          *      Receive the packet.  The OS will discard any data in the
 415          *      packet after "len" bytes.
 416          */
 417 #ifdef WITH_UDPFROMTO
 418         if (dst.ss_family == AF_INET) {
 419                 data_len = recvfromto(sockfd, buf, len, flags,
 420                                       (struct sockaddr *)&src, &sizeof_src,
 421                                       (struct sockaddr *)&dst, &sizeof_dst);
 422         } else
 423 #endif
 424                 /*
 425                  *      No udpfromto, OR an IPv6 socket.  Fail gracefully.
 426                  */
 427                 data_len = recvfrom(sockfd, buf, len, flags,
 428                                     (struct sockaddr *)&src, &sizeof_src);
 429         if (data_len < 0) {
 430                 free(buf);
 431                 return data_len;
 432         }
 433
 434         if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, &port)) {
 435                 free(buf);
 436                 return -1;      /* Unknown address family, Die Die Die! */
 437         }
 438         *src_port = port;
 439
 440         fr_sockaddr2ipaddr(&dst, sizeof_dst, dst_ipaddr, &port);
 441         *dst_port = port;
 442
 443         /*
 444          *      Different address families should never happen.
 445          */
 446         if (src.ss_family != dst.ss_family) {
 447                 free(buf);
 448                 return -1;
 449         }
 450
 451         /*
 452          *      Tell the caller about the data
 453          */
 454         *pbuf = buf;
 455
 456         return data_len;
 457 }
 458
 459
 460 #define AUTH_PASS_LEN (AUTH_VECTOR_LEN)
 461 /*************************************************************************
 462  *
 463  *      Function: make_secret
 464  *
 465  *      Purpose: Build an encrypted secret value to return in a reply
 466  *               packet.  The secret is hidden by xoring with a MD5 digest
 467  *               created from the shared secret and the authentication
 468  *               vector.  We put them into MD5 in the reverse order from
 469  *               that used when encrypting passwords to RADIUS.
 470  *
 471  *************************************************************************/
 472 static void make_secret(uint8_t *digest, const uint8_t *vector,
 473                         const char *secret, const uint8_t *value)
 474 {
 475         FR_MD5_CTX context;
 476         int             i;
 477
 478         fr_MD5Init(&context);
 479         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
 480         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
 481         fr_MD5Final(digest, &context);
 482
 483         for ( i = 0; i < AUTH_VECTOR_LEN; i++ ) {
 484                 digest[i] ^= value[i];
 485         }
 486 }
 487
 488 #define MAX_PASS_LEN (128)
 489 static void make_passwd(uint8_t *output, size_t *outlen,
 490                         const uint8_t *input, size_t inlen,
 491                         const char *secret, const uint8_t *vector)
 492 {
 493         FR_MD5_CTX context, old;
 494         uint8_t digest[AUTH_VECTOR_LEN];
 495         uint8_t passwd[MAX_PASS_LEN];
 496         int     i, n;
 497         int     len;
 498
 499         /*
 500          *      If the length is zero, round it up.
 501          */
 502         len = inlen;
 503
 504         if (len > MAX_PASS_LEN) len = MAX_PASS_LEN;
 505
 506         memcpy(passwd, input, len);
 507         memset(passwd + len, 0, sizeof(passwd) - len);
 508
 509         if (len == 0) {
 510                 len = AUTH_PASS_LEN;
 511         }
 512
 513         else if ((len & 0x0f) != 0) {
 514                 len += 0x0f;
 515                 len &= ~0x0f;
 516         }
 517         *outlen = len;
 518
 519         fr_MD5Init(&context);
 520         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
 521         old = context;
 522
 523         /*
 524          *      Do first pass.
 525          */
 526         fr_MD5Update(&context, vector, AUTH_PASS_LEN);
 527
 528         for (n = 0; n < len; n += AUTH_PASS_LEN) {
 529                 if (n > 0) {
 530                         context = old;
 531                         fr_MD5Update(&context,
 532                                        passwd + n - AUTH_PASS_LEN,
 533                                        AUTH_PASS_LEN);
 534                 }
 535
 536                 fr_MD5Final(digest, &context);
 537                 for (i = 0; i < AUTH_PASS_LEN; i++) {
 538                         passwd[i + n] ^= digest[i];
 539                 }
 540         }
 541
 542         memcpy(output, passwd, len);
 543 }
 544
 545 static void make_tunnel_passwd(uint8_t *output, size_t *outlen,
 546                                const uint8_t *input, size_t inlen, size_t room,
 547                                const char *secret, const uint8_t *vector)
 548 {
 549         FR_MD5_CTX context, old;
 550         uint8_t digest[AUTH_VECTOR_LEN];
 551         uint8_t passwd[MAX_STRING_LEN + AUTH_VECTOR_LEN];
 552         int     i, n;
 553         int     len;
 554
 555         /*
 556          *      Be paranoid.
 557          */
 558         if (room > 253) room = 253;
 559
 560         /*
 561          *      Account for 2 bytes of the salt, and round the room
 562          *      available down to the nearest multiple of 16.  Then,
 563          *      subtract one from that to account for the length byte,
 564          *      and the resulting number is the upper bound on the data
 565          *      to copy.
 566          *
 567          *      We could short-cut this calculation just be forcing
 568          *      inlen to be no more than 239.  It would work for all
 569          *      VSA's, as we don't pack multiple VSA's into one
 570          *      attribute.
 571          *
 572          *      However, this calculation is more general, if a little
 573          *      complex.  And it will work in the future for all possible
 574          *      kinds of weird attribute packing.
 575          */
 576         room -= 2;
 577         room -= (room & 0x0f);
 578         room--;
 579
 580         if (inlen > room) inlen = room;
 581
 582         /*
 583          *      Length of the encrypted data is password length plus
 584          *      one byte for the length of the password.
 585          */
 586         len = inlen + 1;
 587         if ((len & 0x0f) != 0) {
 588                 len += 0x0f;
 589                 len &= ~0x0f;
 590         }
 591         *outlen = len + 2;      /* account for the salt */
 592
 593         /*
 594          *      Copy the password over.
 595          */
 596         memcpy(passwd + 3, input, inlen);
 597         memset(passwd + 3 + inlen, 0, sizeof(passwd) - 3 - inlen);
 598
 599         /*
 600          *      Generate salt.  The RFC's say:
 601          *
 602          *      The high bit of salt[0] must be set, each salt in a
 603          *      packet should be unique, and they should be random
 604          *
 605          *      So, we set the high bit, add in a counter, and then
 606          *      add in some CSPRNG data.  should be OK..
 607          */
 608         passwd[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
 609                      (fr_rand() & 0x07));
 610         passwd[1] = fr_rand();
 611         passwd[2] = inlen;      /* length of the password string */
 612
 613         fr_MD5Init(&context);
 614         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
 615         old = context;
 616
 617         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
 618         fr_MD5Update(&context, &passwd[0], 2);
 619
 620         for (n = 0; n < len; n += AUTH_PASS_LEN) {
 621                 if (n > 0) {
 622                         context = old;
 623                         fr_MD5Update(&context,
 624                                        passwd + 2 + n - AUTH_PASS_LEN,
 625                                        AUTH_PASS_LEN);
 626                 }
 627
 628                 fr_MD5Final(digest, &context);
 629                 for (i = 0; i < AUTH_PASS_LEN; i++) {
 630                         passwd[i + 2 + n] ^= digest[i];
 631                 }
 632         }
 633         memcpy(output, passwd, len + 2);
 634 }
 635
 636 /*
 637  *      Returns the end of the data.
 638  */
 639 static uint8_t *vp2data(const RADIUS_PACKET *packet,
 640                         const RADIUS_PACKET *original,
 641                         const char *secret, const VALUE_PAIR *vp, uint8_t *ptr,
 642                         size_t room)
 643 {
 644         uint32_t lvalue;
 645         size_t len;
 646         const uint8_t *data;
 647         uint8_t array[4];
 648
 649         /*
 650          *      Set up the default sources for the data.
 651          */
 652         data = vp->vp_octets;
 653         len = vp->length;
 654
 655         switch(vp->type) {
 656         case PW_TYPE_STRING:
 657         case PW_TYPE_OCTETS:
 658         case PW_TYPE_IFID:
 659         case PW_TYPE_IPV6ADDR:
 660         case PW_TYPE_IPV6PREFIX:
 661         case PW_TYPE_ABINARY:
 662                 /* nothing more to do */
 663                 break;
 664
 665         case PW_TYPE_BYTE:
 666                 len = 1;        /* just in case */
 667                 array[0] = vp->vp_integer & 0xff;
 668                 data = array;
 669                 break;
 670
 671         case PW_TYPE_SHORT:
 672                 len = 2;        /* just in case */
 673                 array[0] = (vp->vp_integer >> 8) & 0xff;
 674                 array[1] = vp->vp_integer & 0xff;
 675                 data = array;
 676                 break;
 677
 678         case PW_TYPE_INTEGER:
 679                 len = 4;        /* just in case */
 680                 lvalue = htonl(vp->vp_integer);
 681                 memcpy(array, &lvalue, sizeof(lvalue));
 682                 data = array;
 683                 break;
 684
 685         case PW_TYPE_IPADDR:
 686                 data = (const uint8_t *) &vp->vp_ipaddr;
 687                 len = 4;        /* just in case */
 688                 break;
 689
 690                 /*
 691                  *  There are no tagged date attributes.
 692                  */
 693         case PW_TYPE_DATE:
 694                 lvalue = htonl(vp->vp_date);
 695                 data = (const uint8_t *) &lvalue;
 696                 len = 4;        /* just in case */
 697                 break;
 698
 699         case PW_TYPE_SIGNED:
 700         {
 701                 int32_t slvalue;
 702
 703                 len = 4;        /* just in case */
 704                 slvalue = htonl(vp->vp_signed);
 705                 memcpy(array, &slvalue, sizeof(slvalue));
 706                 break;
 707         }
 708
 709         case PW_TYPE_TLV:
 710                 data = vp->vp_tlv;
 711                 if (!data) {
 712                         fr_strerror_printf("ERROR: Cannot encode NULL TLV");
 713                         return NULL;
 714                 }
 715                 if (vp->length > room) return 0; /* can't chop TLVs to fit */
 716                 break;
 717
 718         default:                /* unknown type: ignore it */
 719                 fr_strerror_printf("ERROR: Unknown attribute type %d", vp->type);
 720                 return NULL;
 721         }
 722
 723         /*
 724          *      Bound the data to the calling size
 725          */
 726         if (len > room) len = room;
 727
 728         /*
 729          *      Encrypt the various password styles
 730          *
 731          *      Attributes with encrypted values MUST be less than
 732          *      128 bytes long.
 733          */
 734         switch (vp->flags.encrypt) {
 735         case FLAG_ENCRYPT_USER_PASSWORD:
 736                 make_passwd(ptr, &len, data, len,
 737                             secret, packet->vector);
 738                 break;
 739
 740         case FLAG_ENCRYPT_TUNNEL_PASSWORD:
 741                 /*
 742                  *      Check if there's enough room.  If there isn't,
 743                  *      we discard the attribute.
 744                  *
 745                  *      This is ONLY a problem if we have multiple VSA's
 746                  *      in one Vendor-Specific, though.
 747                  */
 748                 if (room < 18) return ptr;
 749
 750                 switch (packet->code) {
 751                 case PW_AUTHENTICATION_ACK:
 752                 case PW_AUTHENTICATION_REJECT:
 753                 case PW_ACCESS_CHALLENGE:
 754                 default:
 755                         if (!original) {
 756                                 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->name);
 757                                 return NULL;
 758                         }
 759                         make_tunnel_passwd(ptr, &len, data, len, room,
 760                                            secret, original->vector);
 761                         break;
 762                 case PW_ACCOUNTING_REQUEST:
 763                 case PW_DISCONNECT_REQUEST:
 764                 case PW_COA_REQUEST:
 765                         make_tunnel_passwd(ptr, &len, data, len, room,
 766                                            secret, packet->vector);
 767                         break;
 768                 }
 769                 break;
 770
 771                 /*
 772                  *      The code above ensures that this attribute
 773                  *      always fits.
 774                  */
 775         case FLAG_ENCRYPT_ASCEND_SECRET:
 776                 make_secret(ptr, packet->vector, secret, data);
 777                 len = AUTH_VECTOR_LEN;
 778                 break;
 779
 780
 781         default:
 782                 /*
 783                  *      Just copy the data over
 784                  */
 785                 memcpy(ptr, data, len);
 786                 break;
 787         } /* switch over encryption flags */
 788
 789         return ptr + len;
 790 }
 791
 792
 793 /*
 794  *      Parse a data structure into a RADIUS attribute.
 795  */
 796 int rad_vp2attr(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
 797                 const char *secret, const VALUE_PAIR *vp, uint8_t *start,
 798                 size_t room)
 799 {
 800         int             vendorcode;
 801         int             len, total_length;
 802         uint32_t        lvalue;
 803         uint8_t         *ptr, *length_ptr, *vsa_length_ptr, *tlv_length_ptr;
 804         uint8_t         *end, *sub_length_ptr; /* evil */
 805
 806         ptr = start;
 807         vendorcode = total_length = 0;
 808         length_ptr = vsa_length_ptr = tlv_length_ptr = sub_length_ptr = NULL;
 809
 810         /*
 811          *      For interoperability, always put vendor attributes
 812          *      into their own VSA.
 813          */
 814         if ((vendorcode = vp->vendor) == 0) {
 815                 if (room < 2) return 0;
 816                 room -= 2;
 817
 818                 *(ptr++) = vp->attribute & 0xff;
 819                 length_ptr = ptr;
 820                 *(ptr++) = 2;
 821                 total_length += 2;
 822
 823         } else {
 824                 int vsa_tlen = 1;
 825                 int vsa_llen = 1;
 826                 int vsa_offset = 0;
 827                 DICT_VENDOR *dv = dict_vendorbyvalue(vendorcode);
 828
 829                 /*
 830                  *      This must be an RFC-format attribute.  If it
 831                  *      wasn't, then the "decode" function would have
 832                  *      made a Vendor-Specific attribute (i.e. type
 833                  *      26), and we would have "vendorcode == 0" here.
 834                  */
 835                 if (dv) {
 836                         vsa_tlen = dv->type;
 837                         vsa_llen = dv->length;
 838                         if (dv->flags) vsa_offset = 1;
 839                 }
 840
 841                 if (room < (6 + vsa_tlen + vsa_llen + vsa_offset)) return 0;
 842                 room -= 6 + vsa_tlen + vsa_llen + vsa_offset;
 843
 844                 /*
 845                  *      Build a VSA header.
 846                  */
 847                 *ptr++ = PW_VENDOR_SPECIFIC;
 848                 vsa_length_ptr = ptr;
 849                 *ptr++ = 6;
 850                 lvalue = htonl(vendorcode);
 851                 memcpy(ptr, &lvalue, 4);
 852                 ptr += 4;
 853                 total_length += 6;
 854
 855                 switch (vsa_tlen) {
 856                 case 1:
 857                         ptr[0] = (vp->attribute & 0xFF);
 858                         break;
 859
 860                 case 2:
 861                         ptr[0] = ((vp->attribute >> 8) & 0xFF);
 862                         ptr[1] = (vp->attribute & 0xFF);
 863                         break;
 864
 865                 case 4:
 866                         ptr[0] = 0;
 867                         ptr[1] = 0;
 868                         ptr[2] = ((vp->attribute >> 8) & 0xFF);
 869                         ptr[3] = (vp->attribute & 0xFF);
 870                         break;
 871
 872                 default:
 873                         return 0; /* silently discard it */
 874                 }
 875                 ptr += vsa_tlen;
 876
 877                 switch (vsa_llen) {
 878                 case 0:
 879                         length_ptr = vsa_length_ptr;
 880                         vsa_length_ptr = NULL;
 881                         break;
 882                 case 1:
 883                         ptr[0] = 0;
 884                         length_ptr = ptr;
 885                         break;
 886                 case 2:
 887                         ptr[0] = 0;
 888                         ptr[1] = 0;
 889                         length_ptr = ptr + 1;
 890                         break;
 891
 892                 default:
 893                         return 0; /* silently discard it */
 894                 }
 895                 ptr += vsa_llen;
 896
 897                 /*
 898                  *      Allow for some continuation.
 899                  */
 900                 if (vsa_offset) {
 901                         ptr[0] = 0x00;
 902                         ptr++;
 903
 904                         /*
 905                          *      Ignore TLVs that don't have data, OR
 906                          *      have too much data to fit in the
 907                          *      packet, OR have too much data to fit
 908                          *      in the attribute
 909                          *
 910                          *      This shouldn't happen in normal
 911                          *      operation, as the code assumes that
 912                          *      the "tlv" type shouldn't be used.
 913                          */
 914                         if (vp->flags.has_tlv &&
 915                             (!vp->vp_tlv || (vp->length > room) ||
 916
 917                              /*
 918                               *         6 + 1 (vsa_tlen) + 1 (vsa_llen)
 919                               *         + 1 (vsa_offset).
 920                               */
 921                              (vp->length > (255 - 9)))) return 0;
 922
 923
 924                         /*
 925                          *      sub-TLV's can only be in one format.
 926                          */
 927                         if (vp->flags.is_tlv) {
 928                                 if (room < 2) return 0;
 929                                 room -= 2;
 930
 931                                 *(ptr++) = (vp->attribute & 0xff00) >> 8;
 932                                 tlv_length_ptr = ptr;
 933                                 *(ptr++) = 2;
 934                                 vsa_offset += 2;
 935
 936                                 /*
 937                                  *      WiMAX is like sticking knitting
 938                                  *      needles up your nose, and claiming
 939                                  *      you like it.
 940                                  */
 941                                 if ((vp->attribute & 0xff0000) != 0) {
 942                                         *(ptr++) = (vp->attribute >> 16) & 0xff;
 943                                         sub_length_ptr = ptr;
 944                                         *(ptr++) = 2;
 945                                         vsa_offset += 2;
 946                                         *tlv_length_ptr += 2;
 947                                 }
 948                         }
 949                 }
 950
 951                 total_length += vsa_tlen + vsa_llen + vsa_offset;
 952                 if (vsa_length_ptr) *vsa_length_ptr += vsa_tlen + vsa_llen + vsa_offset;
 953                 *length_ptr += vsa_tlen + vsa_llen + vsa_offset;
 954         }
 955
 956         /*
 957          *      Insert tags for string attributes.  They go BEFORE
 958          *      the string.
 959          */
 960         if (vp->flags.has_tag && (vp->type == PW_TYPE_STRING) &&
 961             (TAG_VALID(vp->flags.tag) ||
 962              (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD))) {
 963                 if (room < (1 + vp->length)) return 0;
 964
 965                 ptr[0] = vp->flags.tag;
 966                 end = vp2data(packet, original, secret, vp, ptr + 1,
 967                               (end - ptr) - 1);
 968         } else {
 969                 if (room < vp->length) return 0;
 970                 end = vp2data(packet, original, secret, vp, ptr,
 971                               (end - ptr));
 972         }
 973         if (!end) return -1;
 974
 975         /*
 976          *      Insert tags for integer attributes.  They go at the START
 977          *      of the integer, and over-write the first byte.
 978          */
 979         if (vp->flags.has_tag && (vp->type == PW_TYPE_INTEGER)) {
 980                 ptr[0] = vp->flags.tag;
 981         }
 982
 983         /*
 984          *      RFC 2865 section 5 says that zero-length attributes
 985          *      MUST NOT be sent.
 986          *
 987          *      ... and the WiMAX forum ignores this... because of
 988          *      one vendor.  Don't they have anything better to do
 989          *      with their time?
 990          */
 991         if ((end == ptr) &&
 992             (vp->attribute != PW_CHARGEABLE_USER_IDENTITY)) return 0;
 993
 994         len = (end - ptr);
 995
 996         /*
 997          *      Update the various lengths.
 998          */
 999         *length_ptr += len;
1000         if (vsa_length_ptr) *vsa_length_ptr += len;
1001         if (tlv_length_ptr) *tlv_length_ptr += len;
1002         if (sub_length_ptr) *sub_length_ptr += len;
1003         ptr += len;
1004         total_length += len;
1005
1006         return total_length;    /* of attribute */
1007 }
1008
1009 static int rad_encode_wimax(const RADIUS_PACKET *packet,
1010                             const RADIUS_PACKET *original,
1011                             const char *secret, VALUE_PAIR *vp,
1012                             uint8_t *start, size_t room)
1013 {
1014         int len, total_len = 0;
1015         uint8_t *wimax = NULL;
1016         uint8_t *ptr = start;
1017
1018 redo:
1019         len = rad_vp2attr(packet, original, secret, vp, ptr,
1020                           (start + room) - ptr);
1021         if (len <= 0) return total_len;
1022
1023         /*
1024          *      After adding an attribute with the simplest
1025          *      encoding, check to see if we can append it to
1026          *      the previous one.
1027          */
1028         if (wimax && (memcmp(wimax + 2, ptr + 2, 5) == 0)) {
1029                 if ((wimax[1] + (ptr[1] - 6)) <= 255) {
1030                         unsigned int hack;
1031
1032                         hack = ptr[7] - 3;
1033                         memmove(ptr, ptr + 9, hack);
1034                         wimax[1] += hack;
1035                         wimax[7] += hack;
1036                         len -= 9;
1037
1038                 } else {
1039                         wimax[8] = 0x80; /* set continuation */
1040                         wimax = ptr;
1041                 }
1042         } else {
1043                 wimax = ptr;
1044         }
1045
1046         total_len += len;
1047         ptr += len;
1048
1049         vp->flags.encoded = 1;
1050         vp = vp->next;
1051
1052         if (vp && vp->flags.is_tlv) goto redo;
1053
1054         return total_len;
1055 }
1056
1057
1058 /*
1059  *      Encode a packet.
1060  */
1061 int rad_encode(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1062                const char *secret)
1063 {
1064         radius_packet_t *hdr;
1065         uint8_t         *ptr;
1066         uint16_t        total_length;
1067         int             len;
1068         VALUE_PAIR      *reply;
1069         const char      *what;
1070         char            ip_buffer[128];
1071
1072         /*
1073          *      A 4K packet, aligned on 64-bits.
1074          */
1075         uint64_t        data[MAX_PACKET_LEN / sizeof(uint64_t)];
1076
1077         if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1078                 what = fr_packet_codes[packet->code];
1079         } else {
1080                 what = "Reply";
1081         }
1082
1083         DEBUG("Sending %s of id %d to %s port %d\n",
1084               what, packet->id,
1085               inet_ntop(packet->dst_ipaddr.af,
1086                         &packet->dst_ipaddr.ipaddr,
1087                         ip_buffer, sizeof(ip_buffer)),
1088               packet->dst_port);
1089
1090         /*
1091          *      Double-check some things based on packet code.
1092          */
1093         switch (packet->code) {
1094         case PW_AUTHENTICATION_ACK:
1095         case PW_AUTHENTICATION_REJECT:
1096         case PW_ACCESS_CHALLENGE:
1097                 if (!original) {
1098                         fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1099                         return -1;
1100                 }
1101                 break;
1102
1103                 /*
1104                  *      These packet vectors start off as all zero.
1105                  */
1106         case PW_ACCOUNTING_REQUEST:
1107         case PW_DISCONNECT_REQUEST:
1108         case PW_COA_REQUEST:
1109                 memset(packet->vector, 0, sizeof(packet->vector));
1110                 break;
1111
1112         default:
1113                 break;
1114         }
1115
1116         /*
1117          *      Use memory on the stack, until we know how
1118          *      large the packet will be.
1119          */
1120         hdr = (radius_packet_t *) data;
1121
1122         /*
1123          *      Build standard header
1124          */
1125         hdr->code = packet->code;
1126         hdr->id = packet->id;
1127
1128         memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1129
1130         total_length = AUTH_HDR_LEN;
1131
1132         /*
1133          *      Load up the configuration values for the user
1134          */
1135         ptr = hdr->data;
1136         packet->offset = 0;
1137
1138         /*
1139          *      FIXME: Loop twice over the reply list.  The first time,
1140          *      calculate the total length of data.  The second time,
1141          *      allocate the memory, and fill in the VP's.
1142          *
1143          *      Hmm... this may be slower than just doing a small
1144          *      memcpy.
1145          */
1146
1147         /*
1148          *      Loop over the reply attributes for the packet.
1149          */
1150         for (reply = packet->vps; reply; reply = reply->next) {
1151                 /*
1152                  *      Ignore non-wire attributes
1153                  */
1154                 if ((reply->vendor == 0) &&
1155                     ((reply->attribute & 0xFFFF) > 0xff)) {
1156 #ifndef NDEBUG
1157                         /*
1158                          *      Permit the admin to send BADLY formatted
1159                          *      attributes with a debug build.
1160                          */
1161                         if (reply->attribute == PW_RAW_ATTRIBUTE) {
1162                                 memcpy(ptr, reply->vp_octets, reply->length);
1163                                 len = reply->length;
1164                                 goto next;
1165                         }
1166 #endif
1167                         continue;
1168                 }
1169
1170                 /*
1171                  *      Set the Message-Authenticator to the correct
1172                  *      length and initial value.
1173                  */
1174                 if (reply->attribute == PW_MESSAGE_AUTHENTICATOR) {
1175                         reply->length = AUTH_VECTOR_LEN;
1176                         memset(reply->vp_strvalue, 0, AUTH_VECTOR_LEN);
1177
1178                         /*
1179                          *      Cache the offset to the
1180                          *      Message-Authenticator
1181                          */
1182                         packet->offset = total_length;
1183                 }
1184
1185                 /*
1186                  *      Print out ONLY the attributes which
1187                  *      we're sending over the wire, and print
1188                  *      them out BEFORE they're encrypted.
1189                  */
1190                 debug_pair(reply);
1191
1192                 /*
1193                  *      Skip attributes that are encoded.
1194                  */
1195                 if (reply->flags.encoded) continue;
1196
1197                 if (reply->flags.is_tlv) {
1198                         len = rad_encode_wimax(packet, original, secret,
1199                                                reply, ptr,
1200                                                ((uint8_t *) data) + sizeof(data) - ptr);
1201                 } else {
1202
1203                         len = rad_vp2attr(packet, original, secret, reply, ptr,
1204                                           ((uint8_t *) data) + sizeof(data) - ptr);
1205                 }
1206
1207                 if (len < 0) return -1;
1208
1209         next:
1210                 ptr += len;
1211                 total_length += len;
1212         } /* done looping over all attributes */
1213
1214         /*
1215          *      Fill in the rest of the fields, and copy the data over
1216          *      from the local stack to the newly allocated memory.
1217          *
1218          *      Yes, all this 'memcpy' is slow, but it means
1219          *      that we only allocate the minimum amount of
1220          *      memory for a request.
1221          */
1222         packet->data_len = total_length;
1223         packet->data = (uint8_t *) malloc(packet->data_len);
1224         if (!packet->data) {
1225                 fr_strerror_printf("Out of memory");
1226                 return -1;
1227         }
1228
1229         memcpy(packet->data, hdr, packet->data_len);
1230         hdr = (radius_packet_t *) packet->data;
1231
1232         total_length = htons(total_length);
1233         memcpy(hdr->length, &total_length, sizeof(total_length));
1234
1235         return 0;
1236 }
1237
1238
1239 /*
1240  *      Sign a previously encoded packet.
1241  */
1242 int rad_sign(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1243              const char *secret)
1244 {
1245         radius_packet_t *hdr = (radius_packet_t *)packet->data;
1246
1247         /*
1248          *      It wasn't assigned an Id, this is bad!
1249          */
1250         if (packet->id < 0) {
1251                 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1252                 return -1;
1253         }
1254
1255         if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1256             (packet->offset < 0)) {
1257                 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1258                 return -1;
1259         }
1260
1261         /*
1262          *      If there's a Message-Authenticator, update it
1263          *      now, BEFORE updating the authentication vector.
1264          */
1265         if (packet->offset > 0) {
1266                 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1267
1268                 switch (packet->code) {
1269                 case PW_ACCOUNTING_REQUEST:
1270                 case PW_ACCOUNTING_RESPONSE:
1271                 case PW_DISCONNECT_REQUEST:
1272                 case PW_DISCONNECT_ACK:
1273                 case PW_DISCONNECT_NAK:
1274                 case PW_COA_REQUEST:
1275                 case PW_COA_ACK:
1276                 case PW_COA_NAK:
1277                         memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1278                         break;
1279
1280                 case PW_AUTHENTICATION_ACK:
1281                 case PW_AUTHENTICATION_REJECT:
1282                 case PW_ACCESS_CHALLENGE:
1283                         if (!original) {
1284                                 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1285                                 return -1;
1286                         }
1287                         memcpy(hdr->vector, original->vector,
1288                                AUTH_VECTOR_LEN);
1289                         break;
1290
1291                 default:        /* others have vector already set to zero */
1292                         break;
1293
1294                 }
1295
1296                 /*
1297                  *      Set the authentication vector to zero,
1298                  *      calculate the signature, and put it
1299                  *      into the Message-Authenticator
1300                  *      attribute.
1301                  */
1302                 fr_hmac_md5(packet->data, packet->data_len,
1303                             (const uint8_t *) secret, strlen(secret),
1304                             calc_auth_vector);
1305                 memcpy(packet->data + packet->offset + 2,
1306                        calc_auth_vector, AUTH_VECTOR_LEN);
1307
1308                 /*
1309                  *      Copy the original request vector back
1310                  *      to the raw packet.
1311                  */
1312                 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1313         }
1314
1315         /*
1316          *      Switch over the packet code, deciding how to
1317          *      sign the packet.
1318          */
1319         switch (packet->code) {
1320                 /*
1321                  *      Request packets are not signed, bur
1322                  *      have a random authentication vector.
1323                  */
1324         case PW_AUTHENTICATION_REQUEST:
1325         case PW_STATUS_SERVER:
1326                 break;
1327
1328                 /*
1329                  *      Reply packets are signed with the
1330                  *      authentication vector of the request.
1331                  */
1332         default:
1333                 {
1334                         uint8_t digest[16];
1335
1336                         FR_MD5_CTX      context;
1337                         fr_MD5Init(&context);
1338                         fr_MD5Update(&context, packet->data, packet->data_len);
1339                         fr_MD5Update(&context, (const uint8_t *) secret,
1340                                      strlen(secret));
1341                         fr_MD5Final(digest, &context);
1342
1343                         memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1344                         memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1345                         break;
1346                 }
1347         }/* switch over packet codes */
1348
1349         return 0;
1350 }
1351
1352 /*
1353  *      Reply to the request.  Also attach
1354  *      reply attribute value pairs and any user message provided.
1355  */
1356 int rad_send(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1357              const char *secret)
1358 {
1359         VALUE_PAIR              *reply;
1360         const char              *what;
1361         char                    ip_buffer[128];
1362
1363         /*
1364          *      Maybe it's a fake packet.  Don't send it.
1365          */
1366         if (!packet || (packet->sockfd < 0)) {
1367                 return 0;
1368         }
1369
1370         if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1371                 what = fr_packet_codes[packet->code];
1372         } else {
1373                 what = "Reply";
1374         }
1375
1376         /*
1377          *  First time through, allocate room for the packet
1378          */
1379         if (!packet->data) {
1380                 /*
1381                  *      Encode the packet.
1382                  */
1383                 if (rad_encode(packet, original, secret) < 0) {
1384                         return -1;
1385                 }
1386
1387                 /*
1388                  *      Re-sign it, including updating the
1389                  *      Message-Authenticator.
1390                  */
1391                 if (rad_sign(packet, original, secret) < 0) {
1392                         return -1;
1393                 }
1394
1395                 /*
1396                  *      If packet->data points to data, then we print out
1397                  *      the VP list again only for debugging.
1398                  */
1399         } else if (fr_debug_flag) {
1400                 DEBUG("Sending %s of id %d to %s port %d\n", what, packet->id,
1401                       inet_ntop(packet->dst_ipaddr.af,
1402                                 &packet->dst_ipaddr.ipaddr,
1403                                 ip_buffer, sizeof(ip_buffer)),
1404                       packet->dst_port);
1405
1406                 for (reply = packet->vps; reply; reply = reply->next) {
1407                         if ((reply->vendor == 0) &&
1408                             ((reply->attribute & 0xFFFF) > 0xff)) continue;
1409                         debug_pair(reply);
1410                 }
1411         }
1412
1413         /*
1414          *      And send it on it's way.
1415          */
1416         return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
1417                           &packet->src_ipaddr, packet->src_port,
1418                           &packet->dst_ipaddr, packet->dst_port);
1419 }
1420
1421 /*
1422  *      Do a comparison of two authentication digests by comparing
1423  *      the FULL digest.  Otehrwise, the server can be subject to
1424  *      timing attacks that allow attackers find a valid message
1425  *      authenticator.
1426  *
1427  *      http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
1428  */
1429 static int digest_cmp(const uint8_t *a, const uint8_t *b, size_t length)
1430 {
1431         int result = 0;
1432         size_t i;
1433
1434         for (i = 0; i < length; i++) {
1435                 result |= a[i] ^ b[i];
1436         }
1437
1438         return result;          /* 0 is OK, !0 is !OK, just like memcmp */
1439 }
1440
1441
1442 /*
1443  *      Validates the requesting client NAS.  Calculates the
1444  *      signature based on the clients private key.
1445  */
1446 static int calc_acctdigest(RADIUS_PACKET *packet, const char *secret)
1447 {
1448         uint8_t         digest[AUTH_VECTOR_LEN];
1449         FR_MD5_CTX              context;
1450
1451         /*
1452          *      Zero out the auth_vector in the received packet.
1453          *      Then append the shared secret to the received packet,
1454          *      and calculate the MD5 sum. This must be the same
1455          *      as the original MD5 sum (packet->vector).
1456          */
1457         memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1458
1459         /*
1460          *  MD5(packet + secret);
1461          */
1462         fr_MD5Init(&context);
1463         fr_MD5Update(&context, packet->data, packet->data_len);
1464         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1465         fr_MD5Final(digest, &context);
1466
1467         /*
1468          *      Return 0 if OK, 2 if not OK.
1469          */
1470         if (digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
1471         return 0;
1472 }
1473
1474
1475 /*
1476  *      Validates the requesting client NAS.  Calculates the
1477  *      signature based on the clients private key.
1478  */
1479 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1480                             const char *secret)
1481 {
1482         uint8_t         calc_digest[AUTH_VECTOR_LEN];
1483         FR_MD5_CTX              context;
1484
1485         /*
1486          *      Very bad!
1487          */
1488         if (original == NULL) {
1489                 return 3;
1490         }
1491
1492         /*
1493          *  Copy the original vector in place.
1494          */
1495         memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
1496
1497         /*
1498          *  MD5(packet + secret);
1499          */
1500         fr_MD5Init(&context);
1501         fr_MD5Update(&context, packet->data, packet->data_len);
1502         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1503         fr_MD5Final(calc_digest, &context);
1504
1505         /*
1506          *  Copy the packet's vector back to the packet.
1507          */
1508         memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
1509
1510         /*
1511          *      Return 0 if OK, 2 if not OK.
1512          */
1513         if (digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
1514         return 0;
1515 }
1516
1517
1518 /*
1519  *      See if the data pointed to by PTR is a valid RADIUS packet.
1520  *
1521  *      packet is not 'const * const' because we may update data_len,
1522  *      if there's more data in the UDP packet than in the RADIUS packet.
1523  */
1524 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
1525 {
1526         uint8_t                 *attr;
1527         int                     totallen;
1528         int                     count;
1529         radius_packet_t         *hdr;
1530         char                    host_ipaddr[128];
1531         int                     require_ma = 0;
1532         int                     seen_ma = 0;
1533         int                     num_attributes;
1534
1535         /*
1536          *      Check for packets smaller than the packet header.
1537          *
1538          *      RFC 2865, Section 3., subsection 'length' says:
1539          *
1540          *      "The minimum length is 20 ..."
1541          */
1542         if (packet->data_len < AUTH_HDR_LEN) {
1543                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %d < minimum %d)",
1544                            inet_ntop(packet->src_ipaddr.af,
1545                                      &packet->src_ipaddr.ipaddr,
1546                                      host_ipaddr, sizeof(host_ipaddr)),
1547                                    (int) packet->data_len, AUTH_HDR_LEN);
1548                 return 0;
1549         }
1550
1551         /*
1552          *      RFC 2865, Section 3., subsection 'length' says:
1553          *
1554          *      " ... and maximum length is 4096."
1555          */
1556         if (packet->data_len > MAX_PACKET_LEN) {
1557                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (received %d > maximum %d)",
1558                            inet_ntop(packet->src_ipaddr.af,
1559                                      &packet->src_ipaddr.ipaddr,
1560                                      host_ipaddr, sizeof(host_ipaddr)),
1561                                    (int) packet->data_len, MAX_PACKET_LEN);
1562                 return 0;
1563         }
1564
1565         /*
1566          *      Check for packets with mismatched size.
1567          *      i.e. We've received 128 bytes, and the packet header
1568          *      says it's 256 bytes long.
1569          */
1570         totallen = (packet->data[2] << 8) | packet->data[3];
1571         hdr = (radius_packet_t *)packet->data;
1572
1573         /*
1574          *      Code of 0 is not understood.
1575          *      Code of 16 or greate is not understood.
1576          */
1577         if ((hdr->code == 0) ||
1578             (hdr->code >= FR_MAX_PACKET_CODE)) {
1579                 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code%d ",
1580                            inet_ntop(packet->src_ipaddr.af,
1581                                      &packet->src_ipaddr.ipaddr,
1582                                      host_ipaddr, sizeof(host_ipaddr)),
1583                            hdr->code);
1584                 return 0;
1585         }
1586
1587         /*
1588          *      Message-Authenticator is required in Status-Server
1589          *      packets, otherwise they can be trivially forged.
1590          */
1591         if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
1592
1593         /*
1594          *      It's also required if the caller asks for it.
1595          */
1596         if (flags) require_ma = 1;
1597
1598         /*
1599          *      Repeat the length checks.  This time, instead of
1600          *      looking at the data we received, look at the value
1601          *      of the 'length' field inside of the packet.
1602          *
1603          *      Check for packets smaller than the packet header.
1604          *
1605          *      RFC 2865, Section 3., subsection 'length' says:
1606          *
1607          *      "The minimum length is 20 ..."
1608          */
1609         if (totallen < AUTH_HDR_LEN) {
1610                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %d < minimum %d)",
1611                            inet_ntop(packet->src_ipaddr.af,
1612                                      &packet->src_ipaddr.ipaddr,
1613                                      host_ipaddr, sizeof(host_ipaddr)),
1614                            totallen, AUTH_HDR_LEN);
1615                 return 0;
1616         }
1617
1618         /*
1619          *      And again, for the value of the 'length' field.
1620          *
1621          *      RFC 2865, Section 3., subsection 'length' says:
1622          *
1623          *      " ... and maximum length is 4096."
1624          */
1625         if (totallen > MAX_PACKET_LEN) {
1626                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (length %d > maximum %d)",
1627                            inet_ntop(packet->src_ipaddr.af,
1628                                      &packet->src_ipaddr.ipaddr,
1629                                      host_ipaddr, sizeof(host_ipaddr)),
1630                            totallen, MAX_PACKET_LEN);
1631                 return 0;
1632         }
1633
1634         /*
1635          *      RFC 2865, Section 3., subsection 'length' says:
1636          *
1637          *      "If the packet is shorter than the Length field
1638          *      indicates, it MUST be silently discarded."
1639          *
1640          *      i.e. No response to the NAS.
1641          */
1642         if (packet->data_len < totallen) {
1643                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %d octets, packet length says %d",
1644                            inet_ntop(packet->src_ipaddr.af,
1645                                      &packet->src_ipaddr.ipaddr,
1646                                      host_ipaddr, sizeof(host_ipaddr)),
1647                                    (int) packet->data_len, totallen);
1648                 return 0;
1649         }
1650
1651         /*
1652          *      RFC 2865, Section 3., subsection 'length' says:
1653          *
1654          *      "Octets outside the range of the Length field MUST be
1655          *      treated as padding and ignored on reception."
1656          */
1657         if (packet->data_len > totallen) {
1658                 /*
1659                  *      We're shortening the packet below, but just
1660                  *      to be paranoid, zero out the extra data.
1661                  */
1662                 memset(packet->data + totallen, 0, packet->data_len - totallen);
1663                 packet->data_len = totallen;
1664         }
1665
1666         /*
1667          *      Walk through the packet's attributes, ensuring that
1668          *      they add up EXACTLY to the size of the packet.
1669          *
1670          *      If they don't, then the attributes either under-fill
1671          *      or over-fill the packet.  Any parsing of the packet
1672          *      is impossible, and will result in unknown side effects.
1673          *
1674          *      This would ONLY happen with buggy RADIUS implementations,
1675          *      or with an intentional attack.  Either way, we do NOT want
1676          *      to be vulnerable to this problem.
1677          */
1678         attr = hdr->data;
1679         count = totallen - AUTH_HDR_LEN;
1680         num_attributes = 0;
1681
1682         while (count > 0) {
1683                 /*
1684                  *      Attribute number zero is NOT defined.
1685                  */
1686                 if (attr[0] == 0) {
1687                         fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
1688                                    inet_ntop(packet->src_ipaddr.af,
1689                                              &packet->src_ipaddr.ipaddr,
1690                                              host_ipaddr, sizeof(host_ipaddr)));
1691                         return 0;
1692                 }
1693
1694                 /*
1695                  *      Attributes are at LEAST as long as the ID & length
1696                  *      fields.  Anything shorter is an invalid attribute.
1697                  */
1698                 if (attr[1] < 2) {
1699                         fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %d too short",
1700                                    inet_ntop(packet->src_ipaddr.af,
1701                                              &packet->src_ipaddr.ipaddr,
1702                                              host_ipaddr, sizeof(host_ipaddr)),
1703                                    attr[0]);
1704                         return 0;
1705                 }
1706
1707                 /*
1708                  *      Sanity check the attributes for length.
1709                  */
1710                 switch (attr[0]) {
1711                 default:        /* don't do anything by default */
1712                         break;
1713
1714                         /*
1715                          *      If there's an EAP-Message, we require
1716                          *      a Message-Authenticator.
1717                          */
1718                 case PW_EAP_MESSAGE:
1719                         require_ma = 1;
1720                         break;
1721
1722                 case PW_MESSAGE_AUTHENTICATOR:
1723                         if (attr[1] != 2 + AUTH_VECTOR_LEN) {
1724                                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
1725                                            inet_ntop(packet->src_ipaddr.af,
1726                                                      &packet->src_ipaddr.ipaddr,
1727                                                      host_ipaddr, sizeof(host_ipaddr)),
1728                                            attr[1] - 2);
1729                                 return 0;
1730                         }
1731                         seen_ma = 1;
1732                         break;
1733                 }
1734
1735                 /*
1736                  *      FIXME: Look up the base 255 attributes in the
1737                  *      dictionary, and switch over their type.  For
1738                  *      integer/date/ip, the attribute length SHOULD
1739                  *      be 6.
1740                  */
1741                 count -= attr[1];       /* grab the attribute length */
1742                 attr += attr[1];
1743                 num_attributes++;       /* seen one more attribute */
1744         }
1745
1746         /*
1747          *      If the attributes add up to a packet, it's allowed.
1748          *
1749          *      If not, we complain, and throw the packet away.
1750          */
1751         if (count != 0) {
1752                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
1753                            inet_ntop(packet->src_ipaddr.af,
1754                                      &packet->src_ipaddr.ipaddr,
1755                                      host_ipaddr, sizeof(host_ipaddr)));
1756                 return 0;
1757         }
1758
1759         /*
1760          *      If we're configured to look for a maximum number of
1761          *      attributes, and we've seen more than that maximum,
1762          *      then throw the packet away, as a possible DoS.
1763          */
1764         if ((fr_max_attributes > 0) &&
1765             (num_attributes > fr_max_attributes)) {
1766                 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
1767                            inet_ntop(packet->src_ipaddr.af,
1768                                      &packet->src_ipaddr.ipaddr,
1769                                      host_ipaddr, sizeof(host_ipaddr)),
1770                            num_attributes, fr_max_attributes);
1771                 return 0;
1772         }
1773
1774         /*
1775          *      http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
1776          *
1777          *      A packet with an EAP-Message attribute MUST also have
1778          *      a Message-Authenticator attribute.
1779          *
1780          *      A Message-Authenticator all by itself is OK, though.
1781          *
1782          *      Similarly, Status-Server packets MUST contain
1783          *      Message-Authenticator attributes.
1784          */
1785         if (require_ma && ! seen_ma) {
1786                 fr_strerror_printf("WARNING: Insecure packet from host %s:  Packet does not contain required Message-Authenticator attribute",
1787                            inet_ntop(packet->src_ipaddr.af,
1788                                      &packet->src_ipaddr.ipaddr,
1789                                      host_ipaddr, sizeof(host_ipaddr)));
1790                 return 0;
1791         }
1792
1793         /*
1794          *      Fill RADIUS header fields
1795          */
1796         packet->code = hdr->code;
1797         packet->id = hdr->id;
1798         memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
1799
1800         return 1;
1801 }
1802
1803
1804 /*
1805  *      Receive UDP client requests, and fill in
1806  *      the basics of a RADIUS_PACKET structure.
1807  */
1808 RADIUS_PACKET *rad_recv(int fd, int flags)
1809 {
1810         int sock_flags = 0;
1811         RADIUS_PACKET           *packet;
1812
1813         /*
1814          *      Allocate the new request data structure
1815          */
1816         if ((packet = malloc(sizeof(*packet))) == NULL) {
1817                 fr_strerror_printf("out of memory");
1818                 return NULL;
1819         }
1820         memset(packet, 0, sizeof(*packet));
1821
1822         if (flags & 0x02) {
1823                 sock_flags = MSG_PEEK;
1824                 flags &= ~0x02;
1825         }
1826
1827         packet->data_len = rad_recvfrom(fd, &packet->data, sock_flags,
1828                                         &packet->src_ipaddr, &packet->src_port,
1829                                         &packet->dst_ipaddr, &packet->dst_port);
1830
1831         /*
1832          *      Check for socket errors.
1833          */
1834         if (packet->data_len < 0) {
1835                 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
1836                 /* packet->data is NULL */
1837                 free(packet);
1838                 return NULL;
1839         }
1840
1841         /*
1842          *      If the packet is too big, then rad_recvfrom did NOT
1843          *      allocate memory.  Instead, it just discarded the
1844          *      packet.
1845          */
1846         if (packet->data_len > MAX_PACKET_LEN) {
1847                 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
1848                 /* packet->data is NULL */
1849                 free(packet);
1850                 return NULL;
1851         }
1852
1853         /*
1854          *      Read no data.  Continue.
1855          *      This check is AFTER the MAX_PACKET_LEN check above, because
1856          *      if the packet is larger than MAX_PACKET_LEN, we also have
1857          *      packet->data == NULL
1858          */
1859         if ((packet->data_len == 0) || !packet->data) {
1860                 fr_strerror_printf("Empty packet: Socket is not ready.");
1861                 free(packet);
1862                 return NULL;
1863         }
1864
1865         /*
1866          *      See if it's a well-formed RADIUS packet.
1867          */
1868         if (!rad_packet_ok(packet, flags)) {
1869                 rad_free(&packet);
1870                 return NULL;
1871         }
1872
1873         /*
1874          *      Remember which socket we read the packet from.
1875          */
1876         packet->sockfd = fd;
1877
1878         /*
1879          *      FIXME: Do even more filtering by only permitting
1880          *      certain IP's.  The problem is that we don't know
1881          *      how to do this properly for all possible clients...
1882          */
1883
1884         /*
1885          *      Explicitely set the VP list to empty.
1886          */
1887         packet->vps = NULL;
1888
1889         if (fr_debug_flag) {
1890                 char host_ipaddr[128];
1891
1892                 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1893                         DEBUG("rad_recv: %s packet from host %s port %d",
1894                               fr_packet_codes[packet->code],
1895                               inet_ntop(packet->src_ipaddr.af,
1896                                         &packet->src_ipaddr.ipaddr,
1897                                         host_ipaddr, sizeof(host_ipaddr)),
1898                               packet->src_port);
1899                 } else {
1900                         DEBUG("rad_recv: Packet from host %s port %d code=%d",
1901                               inet_ntop(packet->src_ipaddr.af,
1902                                         &packet->src_ipaddr.ipaddr,
1903                                         host_ipaddr, sizeof(host_ipaddr)),
1904                               packet->src_port,
1905                               packet->code);
1906                 }
1907                 DEBUG(", id=%d, length=%d\n",
1908                       packet->id, (int) packet->data_len);
1909         }
1910
1911         return packet;
1912 }
1913
1914
1915 /*
1916  *      Verify the signature of a packet.
1917  */
1918 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1919                const char *secret)
1920 {
1921         uint8_t                 *ptr;
1922         int                     length;
1923         int                     attrlen;
1924
1925         if (!packet || !packet->data) return -1;
1926
1927         /*
1928          *      Before we allocate memory for the attributes, do more
1929          *      sanity checking.
1930          */
1931         ptr = packet->data + AUTH_HDR_LEN;
1932         length = packet->data_len - AUTH_HDR_LEN;
1933         while (length > 0) {
1934                 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
1935                 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1936
1937                 attrlen = ptr[1];
1938
1939                 switch (ptr[0]) {
1940                 default:        /* don't do anything. */
1941                         break;
1942
1943                         /*
1944                          *      Note that more than one Message-Authenticator
1945                          *      attribute is invalid.
1946                          */
1947                 case PW_MESSAGE_AUTHENTICATOR:
1948                         memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
1949                         memset(&ptr[2], 0, AUTH_VECTOR_LEN);
1950
1951                         switch (packet->code) {
1952                         default:
1953                                 break;
1954
1955                         case PW_ACCOUNTING_REQUEST:
1956                         case PW_ACCOUNTING_RESPONSE:
1957                         case PW_DISCONNECT_REQUEST:
1958                         case PW_DISCONNECT_ACK:
1959                         case PW_DISCONNECT_NAK:
1960                         case PW_COA_REQUEST:
1961                         case PW_COA_ACK:
1962                         case PW_COA_NAK:
1963                                 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1964                                 break;
1965
1966                         case PW_AUTHENTICATION_ACK:
1967                         case PW_AUTHENTICATION_REJECT:
1968                         case PW_ACCESS_CHALLENGE:
1969                                 if (!original) {
1970                                         fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
1971                                         return -1;
1972                                 }
1973                                 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
1974                                 break;
1975                         }
1976
1977                         fr_hmac_md5(packet->data, packet->data_len,
1978                                     (const uint8_t *) secret, strlen(secret),
1979                                     calc_auth_vector);
1980                         if (digest_cmp(calc_auth_vector, msg_auth_vector,
1981                                    sizeof(calc_auth_vector)) != 0) {
1982                                 char buffer[32];
1983                                 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator!  (Shared secret is incorrect.)",
1984                                            inet_ntop(packet->src_ipaddr.af,
1985                                                      &packet->src_ipaddr.ipaddr,
1986                                                      buffer, sizeof(buffer)));
1987                                 /* Silently drop packet, according to RFC 3579 */
1988                                 return -1;
1989                         } /* else the message authenticator was good */
1990
1991                         /*
1992                          *      Reinitialize Authenticators.
1993                          */
1994                         memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
1995                         memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
1996                         break;
1997                 } /* switch over the attributes */
1998
1999                 ptr += attrlen;
2000                 length -= attrlen;
2001         } /* loop over the packet, sanity checking the attributes */
2002
2003         /*
2004          *      It looks like a RADIUS packet, but we can't validate
2005          *      the signature.
2006          */
2007         if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2008                 char buffer[32];
2009                 fr_strerror_printf("Received Unknown packet code %d "
2010                            "from client %s port %d: Cannot validate signature.",
2011                            packet->code,
2012                            inet_ntop(packet->src_ipaddr.af,
2013                                      &packet->src_ipaddr.ipaddr,
2014                                      buffer, sizeof(buffer)),
2015                            packet->src_port);
2016                 return -1;
2017         }
2018
2019         /*
2020          *      Calculate and/or verify digest.
2021          */
2022         switch(packet->code) {
2023                 int rcode;
2024                 char buffer[32];
2025
2026                 case PW_AUTHENTICATION_REQUEST:
2027                 case PW_STATUS_SERVER:
2028                         /*
2029                          *      The authentication vector is random
2030                          *      nonsense, invented by the client.
2031                          */
2032                         break;
2033
2034                 case PW_COA_REQUEST:
2035                 case PW_DISCONNECT_REQUEST:
2036                 case PW_ACCOUNTING_REQUEST:
2037                         if (calc_acctdigest(packet, secret) > 1) {
2038                                 fr_strerror_printf("Received %s packet "
2039                                            "from %s with invalid signature!  (Shared secret is incorrect.)",
2040                                            fr_packet_codes[packet->code],
2041                                            inet_ntop(packet->src_ipaddr.af,
2042                                                      &packet->src_ipaddr.ipaddr,
2043                                                      buffer, sizeof(buffer)));
2044                                 return -1;
2045                         }
2046                         break;
2047
2048                         /* Verify the reply digest */
2049                 case PW_AUTHENTICATION_ACK:
2050                 case PW_AUTHENTICATION_REJECT:
2051                 case PW_ACCESS_CHALLENGE:
2052                 case PW_ACCOUNTING_RESPONSE:
2053                 case PW_DISCONNECT_ACK:
2054                 case PW_DISCONNECT_NAK:
2055                 case PW_COA_ACK:
2056                 case PW_COA_NAK:
2057                         rcode = calc_replydigest(packet, original, secret);
2058                         if (rcode > 1) {
2059                                 fr_strerror_printf("Received %s packet "
2060                                            "from client %s port %d with invalid signature (err=%d)!  (Shared secret is incorrect.)",
2061                                            fr_packet_codes[packet->code],
2062                                            inet_ntop(packet->src_ipaddr.af,
2063                                                      &packet->src_ipaddr.ipaddr,
2064                                                      buffer, sizeof(buffer)),
2065                                            packet->src_port,
2066                                            rcode);
2067                                 return -1;
2068                         }
2069                         break;
2070
2071                 default:
2072                         fr_strerror_printf("Received Unknown packet code %d "
2073                                    "from client %s port %d: Cannot validate signature",
2074                                    packet->code,
2075                                    inet_ntop(packet->src_ipaddr.af,
2076                                              &packet->src_ipaddr.ipaddr,
2077                                                      buffer, sizeof(buffer)),
2078                                    packet->src_port);
2079                         return -1;
2080         }
2081
2082         return 0;
2083 }
2084
2085
2086 static VALUE_PAIR *data2vp(const RADIUS_PACKET *packet,
2087                            const RADIUS_PACKET *original,
2088                            const char *secret, size_t length,
2089                            const uint8_t *data, VALUE_PAIR *vp)
2090 {
2091         int offset = 0;
2092
2093         /*
2094          *      If length is greater than 253, something is SERIOUSLY
2095          *      wrong.
2096          */
2097         if (length > 253) length = 253; /* paranoia (pair-anoia?) */
2098
2099         vp->length = length;
2100         vp->operator = T_OP_EQ;
2101         vp->next = NULL;
2102
2103         /*
2104          *      Handle tags.
2105          */
2106         if (vp->flags.has_tag) {
2107                 if (TAG_VALID(data[0]) ||
2108                     (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD)) {
2109                         /*
2110                          *      Tunnel passwords REQUIRE a tag, even
2111                          *      if don't have a valid tag.
2112                          */
2113                         vp->flags.tag = data[0];
2114
2115                         if ((vp->type == PW_TYPE_STRING) ||
2116                             (vp->type == PW_TYPE_OCTETS)) offset = 1;
2117                 }
2118         }
2119
2120         /*
2121          *      Copy the data to be decrypted
2122          */
2123         memcpy(&vp->vp_octets[0], data + offset, length - offset);
2124         vp->length -= offset;
2125
2126         /*
2127          *      Decrypt the attribute.
2128          */
2129         switch (vp->flags.encrypt) {
2130                 /*
2131                  *  User-Password
2132                  */
2133         case FLAG_ENCRYPT_USER_PASSWORD:
2134                 if (original) {
2135                         rad_pwdecode((char *)vp->vp_strvalue,
2136                                      vp->length, secret,
2137                                      original->vector);
2138                 } else {
2139                         rad_pwdecode((char *)vp->vp_strvalue,
2140                                      vp->length, secret,
2141                                      packet->vector);
2142                 }
2143                 if (vp->attribute == PW_USER_PASSWORD) {
2144                         vp->length = strlen(vp->vp_strvalue);
2145                 }
2146                 break;
2147
2148                 /*
2149                  *      Tunnel-Password's may go ONLY
2150                  *      in response packets.
2151                  */
2152         case FLAG_ENCRYPT_TUNNEL_PASSWORD:
2153                 if (!original) goto raw;
2154
2155                 if (rad_tunnel_pwdecode(vp->vp_octets, &vp->length,
2156                                         secret, original->vector) < 0) {
2157                         goto raw;
2158                 }
2159                 break;
2160
2161                 /*
2162                  *  Ascend-Send-Secret
2163                  *  Ascend-Receive-Secret
2164                  */
2165         case FLAG_ENCRYPT_ASCEND_SECRET:
2166                 if (!original) {
2167                         goto raw;
2168                 } else {
2169                         uint8_t my_digest[AUTH_VECTOR_LEN];
2170                         make_secret(my_digest,
2171                                     original->vector,
2172                                     secret, data);
2173                         memcpy(vp->vp_strvalue, my_digest,
2174                                AUTH_VECTOR_LEN );
2175                         vp->vp_strvalue[AUTH_VECTOR_LEN] = '\0';
2176                         vp->length = strlen(vp->vp_strvalue);
2177                 }
2178                 break;
2179
2180         default:
2181                 break;
2182         } /* switch over encryption flags */
2183
2184
2185         switch (vp->type) {
2186         case PW_TYPE_STRING:
2187         case PW_TYPE_OCTETS:
2188         case PW_TYPE_ABINARY:
2189                 /* nothing more to do */
2190                 break;
2191
2192         case PW_TYPE_BYTE:
2193                 if (vp->length != 1) goto raw;
2194
2195                 vp->vp_integer = vp->vp_octets[0];
2196                 break;
2197
2198
2199         case PW_TYPE_SHORT:
2200                 if (vp->length != 2) goto raw;
2201
2202                 vp->vp_integer = (vp->vp_octets[0] << 8) | vp->vp_octets[1];
2203                 break;
2204
2205         case PW_TYPE_INTEGER:
2206                 if (vp->length != 4) goto raw;
2207
2208                 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2209                 vp->vp_integer = ntohl(vp->vp_integer);
2210
2211                 if (vp->flags.has_tag) vp->vp_integer &= 0x00ffffff;
2212
2213                 /*
2214                  *      Try to get named VALUEs
2215                  */
2216                 {
2217                         DICT_VALUE *dval;
2218                         dval = dict_valbyattr(vp->attribute, vp->vendor,
2219                                               vp->vp_integer);
2220                         if (dval) {
2221                                 strlcpy(vp->vp_strvalue,
2222                                         dval->name,
2223                                         sizeof(vp->vp_strvalue));
2224                         }
2225                 }
2226                 break;
2227
2228         case PW_TYPE_DATE:
2229                 if (vp->length != 4) goto raw;
2230
2231                 memcpy(&vp->vp_date, vp->vp_octets, 4);
2232                 vp->vp_date = ntohl(vp->vp_date);
2233                 break;
2234
2235
2236         case PW_TYPE_IPADDR:
2237                 if (vp->length != 4) goto raw;
2238
2239                 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2240                 break;
2241
2242                 /*
2243                  *      IPv6 interface ID is 8 octets long.
2244                  */
2245         case PW_TYPE_IFID:
2246                 if (vp->length != 8) goto raw;
2247                 /* vp->vp_ifid == vp->vp_octets */
2248                 break;
2249
2250                 /*
2251                  *      IPv6 addresses are 16 octets long
2252                  */
2253         case PW_TYPE_IPV6ADDR:
2254                 if (vp->length != 16) goto raw;
2255                 /* vp->vp_ipv6addr == vp->vp_octets */
2256                 break;
2257
2258                 /*
2259                  *      IPv6 prefixes are 2 to 18 octets long.
2260                  *
2261                  *      RFC 3162: The first octet is unused.
2262                  *      The second is the length of the prefix
2263                  *      the rest are the prefix data.
2264                  *
2265                  *      The prefix length can have value 0 to 128.
2266                  */
2267         case PW_TYPE_IPV6PREFIX:
2268                 if (vp->length < 2 || vp->length > 18) goto raw;
2269                 if (vp->vp_octets[1] > 128) goto raw;
2270
2271                 /*
2272                  *      FIXME: double-check that
2273                  *      (vp->vp_octets[1] >> 3) matches vp->length + 2
2274                  */
2275                 if (vp->length < 18) {
2276                         memset(vp->vp_octets + vp->length, 0,
2277                                18 - vp->length);
2278                 }
2279                 break;
2280
2281         case PW_TYPE_SIGNED:
2282                 if (vp->length != 4) goto raw;
2283
2284                 /*
2285                  *      Overload vp_integer for ntohl, which takes
2286                  *      uint32_t, not int32_t
2287                  */
2288                 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2289                 vp->vp_integer = ntohl(vp->vp_integer);
2290                 memcpy(&vp->vp_signed, &vp->vp_integer, 4);
2291                 break;
2292
2293         case PW_TYPE_TLV:
2294                 vp->length = length;
2295                 vp->vp_tlv = malloc(length);
2296                 if (!vp->vp_tlv) {
2297                         pairfree(&vp);
2298                         fr_strerror_printf("No memory");
2299                         return NULL;
2300                 }
2301                 memcpy(vp->vp_tlv, data, length);
2302                 break;
2303
2304         case PW_TYPE_COMBO_IP:
2305                 if (vp->length == 4) {
2306                         vp->type = PW_TYPE_IPADDR;
2307                         memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2308                         break;
2309
2310                 } else if (vp->length == 16) {
2311                         vp->type = PW_TYPE_IPV6ADDR;
2312                         /* vp->vp_ipv6addr == vp->vp_octets */
2313                         break;
2314
2315                 }
2316                 /* FALL-THROUGH */
2317
2318         default:
2319         raw:
2320                 vp->type = PW_TYPE_OCTETS;
2321                 vp->length = length;
2322                 memcpy(vp->vp_octets, data, length);
2323
2324
2325                 /*
2326                  *      Ensure there's no encryption or tag stuff,
2327                  *      we just pass the attribute as-is.
2328                  */
2329                 memset(&vp->flags, 0, sizeof(vp->flags));
2330         }
2331
2332         return vp;
2333 }
2334
2335 static void rad_sortvp(VALUE_PAIR **head)
2336 {
2337         int swapped;
2338         VALUE_PAIR *vp, **tail;
2339
2340         /*
2341          *      Walk over the VP's, sorting them in order.  Did I
2342          *      mention that I hate WiMAX continuations?
2343          *
2344          *      And bubble sort!  WTF is up with that?
2345          */
2346         do {
2347                 swapped = 0;
2348                 tail = head;
2349                 while (*tail) {
2350                         vp = *tail;
2351                         if (!vp->next) break;
2352
2353                         if (vp->attribute > vp->next->attribute) {
2354                                 *tail = vp->next;
2355                                 vp->next = (*tail)->next;
2356                                 (*tail)->next = vp;
2357                                 swapped = 1;
2358                         }
2359                         tail = &(vp->next);
2360                 }
2361         } while (swapped);
2362 }
2363
2364
2365 /*
2366  *      Walk the packet, looking for continuations of this attribute.
2367  *
2368  *      This is (worst-case) O(N^2) in the number of RADIUS
2369  *      attributes.  That happens only when perverse clients create
2370  *      continued attributes, AND separate the fragmented portions
2371  *      with a lot of other attributes.
2372  *
2373  *      Sane clients should put the fragments next to each other, in
2374  *      which case this is O(N), in the number of fragments.
2375  */
2376 static uint8_t *rad_coalesce(unsigned int attribute, int vendor,
2377                              size_t length, uint8_t *data,
2378                              size_t packet_length, size_t *ptlv_length)
2379
2380 {
2381         uint32_t lvalue;
2382         size_t tlv_length = length;
2383         uint8_t *ptr, *tlv, *tlv_data;
2384
2385         for (ptr = data + length;
2386              ptr != (data + packet_length);
2387              ptr += ptr[1]) {
2388                 /* FIXME: Check that there are 6 bytes of data here... */
2389                 if ((ptr[0] != PW_VENDOR_SPECIFIC) ||
2390                     (ptr[1] < (2 + 4 + 3)) || /* WiMAX VSA with continuation */
2391                     (ptr[2] != 0) || (ptr[3] != 0) ||  /* our requirement */
2392                     (ptr[4] != ((vendor >> 8) & 0xff)) ||
2393                     (ptr[5] != (vendor & 0xff))) {
2394                         continue;
2395                 }
2396
2397                 memcpy(&lvalue, ptr + 2, 4); /* Vendor Id */
2398                 lvalue = ntohl(lvalue);
2399                 lvalue <<= 16;
2400                 lvalue |= ptr[2 + 4]; /* add in VSA number */
2401                 if (lvalue != attribute) continue;
2402
2403                 /*
2404                  *      If the vendor-length is too small, it's badly
2405                  *      formed, so we stop.
2406                  */
2407                 if ((ptr[2 + 4 + 1]) < 3) break;
2408
2409                 tlv_length += ptr[2 + 4 + 1] - 3;
2410                 if ((ptr[2 + 4 + 1 + 1] & 0x80) == 0) break;
2411         }
2412
2413         tlv = tlv_data = malloc(tlv_length);
2414         if (!tlv_data) return NULL;
2415
2416         memcpy(tlv, data, length);
2417         tlv += length;
2418
2419         /*
2420          *      Now we walk the list again, copying the data over to
2421          *      our newly created memory.
2422          */
2423         for (ptr = data + length;
2424              ptr != (data + packet_length);
2425              ptr += ptr[1]) {
2426                 int this_length;
2427
2428                 if ((ptr[0] != PW_VENDOR_SPECIFIC) ||
2429                     (ptr[1] < (2 + 4 + 3)) || /* WiMAX VSA with continuation */
2430                     (ptr[2] != 0) || (ptr[3] != 0)) { /* our requirement */
2431                         continue;
2432                 }
2433
2434                 memcpy(&lvalue, ptr + 2, 4);
2435                 lvalue = ntohl(lvalue);
2436                 lvalue <<= 16;
2437                 lvalue |= ptr[2 + 4];
2438                 if (lvalue != attribute) continue;
2439
2440                 /*
2441                  *      If the vendor-length is too small, it's badly
2442                  *      formed, so we stop.
2443                  */
2444                 if ((ptr[2 + 4 + 1]) < 3) break;
2445
2446                 this_length = ptr[2 + 4 + 1] - 3;
2447                 memcpy(tlv, ptr + 2 + 4 + 3, this_length);
2448                 tlv += this_length;
2449
2450                 ptr[2 + 4] = 0; /* What a hack! */
2451                 if ((ptr[2 + 4 + 1 + 1] & 0x80) == 0) break;
2452         }
2453
2454         *ptlv_length = tlv_length;
2455         return tlv_data;
2456 }
2457
2458 /*
2459  *      Walk over Evil WIMAX Hell, creating attributes.
2460  *
2461  *      Won't someone think of the children?  What if they read this code?
2462  */
2463 static VALUE_PAIR *recurse_evil(const RADIUS_PACKET *packet,
2464                                 const RADIUS_PACKET *original,
2465                                 const char *secret,
2466                                 int attribute, int vendor,
2467                                 uint8_t *ptr, size_t len)
2468 {
2469         VALUE_PAIR *head = NULL;
2470         VALUE_PAIR **tail = &head;
2471         VALUE_PAIR *vp;
2472         uint8_t *y;             /* why do I need to do this? */
2473
2474         /*
2475          *      Sanity check the attribute.
2476          */
2477         for (y = ptr; y < (ptr + len); y += y[1]) {
2478                 if ((y[0] == 0) || ((y + 2) > (ptr + len)) ||
2479                     (y[1] < 2) || ((y + y[1]) > (ptr + len))) {
2480                         return NULL;
2481                 }
2482         }
2483
2484         for (y = ptr; y < (ptr + len); y += y[1]) {
2485                 vp = paircreate(attribute | (ptr[0] << 16), vendor,
2486                                 PW_TYPE_OCTETS);
2487                 if (!vp) {
2488                 error:
2489                         pairfree(&head);
2490                         return NULL;
2491                 }
2492
2493                 if (!data2vp(packet, original, secret,
2494                              y[1] - 2, y + 2, vp)) {
2495                         goto error;
2496                 }
2497
2498                 *tail = vp;
2499                 tail = &(vp->next);
2500         }
2501
2502         return head;
2503 }
2504
2505 /*
2506  *      Start at the *data* portion of a continued attribute.  search
2507  *      through the rest of the attributes to find a matching one, and
2508  *      add it's contents to our contents.
2509  */
2510 static VALUE_PAIR *rad_continuation2vp(const RADIUS_PACKET *packet,
2511                                        const RADIUS_PACKET *original,
2512                                        const char *secret, int attribute,
2513                                        int vendor,
2514                                        int length, /* CANNOT be zero */
2515                                        uint8_t *data, size_t packet_length,
2516                                        int flag, DICT_ATTR *da)
2517 {
2518         size_t tlv_length, left;
2519         uint8_t *ptr;
2520         uint8_t *tlv_data;
2521         VALUE_PAIR *vp, *head, **tail;
2522         DICT_ATTR *tlv_da;
2523
2524         /*
2525          *      Ensure we have data that hasn't been split across
2526          *      multiple attributes.
2527          */
2528         if (flag) {
2529                 tlv_data = rad_coalesce(attribute, vendor, length,
2530                                         data, packet_length, &tlv_length);
2531                 if (!tlv_data) return NULL;
2532         } else {
2533                 tlv_data = data;
2534                 tlv_length = length;
2535         }
2536
2537         /*
2538          *      Non-TLV types cannot be continued across multiple
2539          *      attributes.  This is true even of keys that are
2540          *      encrypted with the tunnel-password method.  The spec
2541          *      says that they can be continued... but also that the
2542          *      keys are 160 bits, which means that they CANNOT be
2543          *      continued.  <sigh>
2544          *
2545          *      Note that we don't check "flag" here.  The calling
2546          *      code ensures that
2547          */
2548         if (!da || (da->type != PW_TYPE_TLV)) {
2549         not_well_formed:
2550                 if (tlv_data == data) { /* true if we had 'goto' */
2551                         tlv_data = malloc(tlv_length);
2552                         if (!tlv_data) return NULL;
2553                         memcpy(tlv_data, data, tlv_length);
2554                 }
2555
2556                 vp = paircreate(attribute, vendor, PW_TYPE_OCTETS);
2557                 if (!vp) return NULL;
2558
2559                 vp->type = PW_TYPE_TLV;
2560                 vp->flags.encrypt = FLAG_ENCRYPT_NONE;
2561                 vp->flags.has_tag = 0;
2562                 vp->flags.is_tlv = 0;
2563                 vp->vp_tlv = tlv_data;
2564                 vp->length = tlv_length;
2565                 return vp;
2566         } /* else it WAS a TLV, go decode the sub-tlv's */
2567
2568         /*
2569          *      Now (sigh) we walk over the TLV, seeing if it is
2570          *      well-formed.
2571          */
2572         left = tlv_length;
2573         for (ptr = tlv_data;
2574              ptr != (tlv_data + tlv_length);
2575              ptr += ptr[1]) {
2576                 if ((left < 2) ||
2577                     (ptr[1] < 2) ||
2578                     (ptr[1] > left)) {
2579                         goto not_well_formed;
2580                 }
2581
2582                 left -= ptr[1];
2583         }
2584
2585         /*
2586          *      Now we walk over the TLV *again*, creating sub-tlv's.
2587          */
2588         head = NULL;
2589         tail = &head;
2590
2591         for (ptr = tlv_data;
2592              ptr != (tlv_data + tlv_length);
2593              ptr += ptr[1]) {
2594
2595                 tlv_da = dict_attrbyvalue(attribute | (ptr[0] << 8), vendor);
2596                 if (tlv_da && (tlv_da->type == PW_TYPE_TLV)) {
2597                         vp = recurse_evil(packet, original, secret,
2598                                           attribute | (ptr[0] << 8),
2599                                           vendor, ptr + 2, ptr[1] - 2);
2600
2601                         if (!vp) {
2602                                 pairfree(&head);
2603                                 goto not_well_formed;
2604                         }
2605                 } else {
2606                         vp = paircreate(attribute | (ptr[0] << 8), vendor,
2607                                         PW_TYPE_OCTETS);
2608                         if (!vp) {
2609                                 pairfree(&head);
2610                                 goto not_well_formed;
2611                         }
2612
2613                         if (!data2vp(packet, original, secret,
2614                                      ptr[1] - 2, ptr + 2, vp)) {
2615                                 pairfree(&head);
2616                                 goto not_well_formed;
2617                         }
2618                 }
2619
2620                 *tail = vp;
2621
2622                 while (*tail) tail = &((*tail)->next);
2623         }
2624
2625         /*
2626          *      TLV's MAY be continued, but sometimes they're not.
2627          */
2628         if (tlv_data != data) free(tlv_data);
2629
2630         if (head->next) rad_sortvp(&head);
2631
2632         return head;
2633 }
2634
2635
2636 /*
2637  *      Parse a RADIUS attribute into a data structure.
2638  */
2639 VALUE_PAIR *rad_attr2vp(const RADIUS_PACKET *packet,
2640                         const RADIUS_PACKET *original,
2641                         const char *secret, int attribute, int vendor,
2642                         int length, const uint8_t *data)
2643 {
2644         VALUE_PAIR *vp;
2645
2646         vp = paircreate(attribute, vendor, PW_TYPE_OCTETS);
2647         if (!vp) return NULL;
2648
2649         return data2vp(packet, original, secret, length, data, vp);
2650 }
2651
2652
2653 /*
2654  *      Calculate/check digest, and decode radius attributes.
2655  *      Returns:
2656  *      -1 on decoding error
2657  *      0 on success
2658  */
2659 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2660                const char *secret)
2661 {
2662         uint32_t                lvalue;
2663         uint32_t                vendorcode;
2664         VALUE_PAIR              **tail;
2665         VALUE_PAIR              *pair;
2666         uint8_t                 *ptr, *vsa_ptr;
2667         int                     packet_length;
2668         int                     attribute;
2669         int                     attrlen;
2670         int                     vendorlen;
2671         radius_packet_t         *hdr;
2672         int                     vsa_tlen, vsa_llen, vsa_offset;
2673         DICT_VENDOR             *dv = NULL;
2674         int                     num_attributes = 0;
2675
2676         /*
2677          *      Extract attribute-value pairs
2678          */
2679         hdr = (radius_packet_t *)packet->data;
2680         ptr = hdr->data;
2681         packet_length = packet->data_len - AUTH_HDR_LEN;
2682
2683         /*
2684          *      There may be VP's already in the packet.  Don't
2685          *      destroy them.
2686          */
2687         for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
2688                 /* nothing */
2689         }
2690
2691         vendorcode = 0;
2692         vendorlen  = 0;
2693         vsa_tlen = vsa_llen = 1;
2694         vsa_offset = 0;
2695
2696         /*
2697          *      We have to read at least two bytes.
2698          *
2699          *      rad_recv() above ensures that this is OK.
2700          */
2701         while (packet_length > 0) {
2702                 attribute = -1;
2703                 attrlen = -1;
2704
2705                 /*
2706                  *      Normal attribute, handle it like normal.
2707                  */
2708                 if (vendorcode == 0) {
2709                         /*
2710                          *      No room to read attr/length,
2711                          *      or bad attribute, or attribute is
2712                          *      too short, or attribute is too long,
2713                          *      stop processing the packet.
2714                          */
2715                         if ((packet_length < 2) ||
2716                             (ptr[0] == 0) ||  (ptr[1] < 2) ||
2717                             (ptr[1] > packet_length)) break;
2718
2719                         attribute = *ptr++;
2720                         attrlen   = *ptr++;
2721
2722                         attrlen -= 2;
2723                         packet_length  -= 2;
2724
2725                         if (attribute != PW_VENDOR_SPECIFIC) goto create_pair;
2726
2727                         /*
2728                          *      No vendor code, or ONLY vendor code.
2729                          */
2730                         if (attrlen <= 4) goto create_pair;
2731
2732                         vendorlen = 0;
2733                 }
2734
2735                 /*
2736                  *      Handle Vendor-Specific
2737                  */
2738                 if (vendorlen == 0) {
2739                         uint8_t *subptr;
2740                         int sublen;
2741                         int myvendor;
2742
2743                         /*
2744                          *      attrlen was checked above.
2745                          */
2746                         memcpy(&lvalue, ptr, 4);
2747                         myvendor = ntohl(lvalue);
2748
2749                         /*
2750                          *      Zero isn't allowed.
2751                          */
2752                         if (myvendor == 0) goto create_pair;
2753
2754                         /*
2755                          *      This is an implementation issue.
2756                          *      We currently pack vendor into the upper
2757                          *      16 bits of a 32-bit attribute number,
2758                          *      so we can't handle vendor numbers larger
2759                          *      than 16 bits.
2760                          */
2761                         if (myvendor > 65535) goto create_pair;
2762
2763                         vsa_tlen = vsa_llen = 1;
2764                         vsa_offset = 0;
2765                         dv = dict_vendorbyvalue(myvendor);
2766                         if (dv) {
2767                                 vsa_tlen = dv->type;
2768                                 vsa_llen = dv->length;
2769                                 if (dv->flags) vsa_offset = 1;
2770                         }
2771
2772                         /*
2773                          *      Sweep through the list of VSA's,
2774                          *      seeing if they exactly fill the
2775                          *      outer Vendor-Specific attribute.
2776                          *
2777                          *      If not, create a raw Vendor-Specific.
2778                          */
2779                         subptr = ptr + 4;
2780                         sublen = attrlen - 4;
2781
2782                         /*
2783                          *      See if we can parse it.
2784                          */
2785                         do {
2786                                 int myattr = 0;
2787
2788                                 /*
2789                                  *      Not enough room for one more
2790                                  *      attribute.  Die!
2791                                  */
2792                                 if (sublen < (vsa_tlen + vsa_llen + vsa_offset)) goto create_pair;
2793
2794                                 /*
2795                                  *      Ensure that the attribute number
2796                                  *      is OK.
2797                                  */
2798                                 switch (vsa_tlen) {
2799                                 case 1:
2800                                         myattr = subptr[0];
2801                                         break;
2802
2803                                 case 2:
2804                                         myattr = (subptr[0] << 8) | subptr[1];
2805                                         break;
2806
2807                                 case 4:
2808                                         if ((subptr[0] != 0) ||
2809                                             (subptr[1] != 0)) goto create_pair;
2810
2811                                         myattr = (subptr[2] << 8) | subptr[3];
2812                                         break;
2813
2814                                         /*
2815                                          *      Our dictionary is broken.
2816                                          */
2817                                 default:
2818                                         goto create_pair;
2819                                 }
2820
2821                                 switch (vsa_llen) {
2822                                 case 0:
2823                                         attribute = myattr;
2824                                         ptr += 4 + vsa_tlen;
2825                                         attrlen -= (4 + vsa_tlen);
2826                                         packet_length -= 4 + vsa_tlen;
2827                                         goto create_pair;
2828
2829                                 case 1:
2830                                         if (subptr[vsa_tlen] < (vsa_tlen + vsa_llen + vsa_offset))
2831                                                 goto create_pair;
2832
2833                                         if (subptr[vsa_tlen] > sublen)
2834                                                 goto create_pair;
2835
2836                                         /*
2837                                          *      WiMAX: 0bCrrrrrrr
2838                                          *      Reserved bits MUST be
2839                                          *      zero.
2840                                          */
2841                                         if (vsa_offset &&
2842                                             ((subptr[vsa_tlen + vsa_llen] & 0x7f) != 0))
2843                                                 goto create_pair;
2844
2845                                         sublen -= subptr[vsa_tlen];
2846                                         subptr += subptr[vsa_tlen];
2847                                         break;
2848
2849                                 case 2:
2850                                         if (subptr[vsa_tlen] != 0) goto create_pair;
2851                                         if (subptr[vsa_tlen + 1] < (vsa_tlen + vsa_llen))
2852                                                 goto create_pair;
2853                                         if (subptr[vsa_tlen + 1] > sublen)
2854                                                 goto create_pair;
2855                                         sublen -= subptr[vsa_tlen + 1];
2856                                         subptr += subptr[vsa_tlen + 1];
2857                                         break;
2858
2859                                         /*
2860                                          *      Our dictionaries are
2861                                          *      broken.
2862                                          */
2863                                 default:
2864                                         goto create_pair;
2865                                 }
2866                         } while (sublen > 0);
2867
2868                         vendorcode = myvendor;
2869                         vendorlen = attrlen - 4;
2870                         packet_length -= 4;
2871
2872                         ptr += 4;
2873                 }
2874
2875                 /*
2876                  *      attrlen is the length of this attribute.
2877                  *      total_len is the length of the encompassing
2878                  *      attribute.
2879                  */
2880                 switch (vsa_tlen) {
2881                 case 1:
2882                         attribute = ptr[0];
2883                         break;
2884
2885                 case 2:
2886                         attribute = (ptr[0] << 8) | ptr[1];
2887                         break;
2888
2889                 default:        /* can't hit this. */
2890                         return -1;
2891                 }
2892                 vsa_ptr = ptr;
2893                 ptr += vsa_tlen;
2894
2895                 switch (vsa_llen) {
2896                 case 1:
2897                         attrlen = ptr[0] - (vsa_tlen + vsa_llen + vsa_offset);
2898                         break;
2899
2900                 case 2:
2901                         attrlen = ptr[1] - (vsa_tlen + vsa_llen);
2902                         break;
2903
2904                 default:        /* can't hit this. */
2905                         return -1;
2906                 }
2907
2908                 ptr += vsa_llen + vsa_offset;
2909                 vendorlen -= vsa_tlen + vsa_llen + vsa_offset + attrlen;
2910                 packet_length -= (vsa_tlen + vsa_llen + vsa_offset);
2911
2912                 /*
2913                  *      Ignore VSAs that have no data.
2914                  */
2915                 if (attrlen == 0) goto next;
2916
2917                 /*
2918                  *      WiMAX attributes of type 0 are ignored.  They
2919                  *      are a secret flag to us that the attribute has
2920                  *      already been dealt with.
2921                  */
2922                 if ((vendorcode == VENDORPEC_WIMAX) && (attribute == 0)) {
2923                         goto next;
2924                 }
2925
2926                 if (vsa_offset) {
2927                         DICT_ATTR *da;
2928
2929                         da = dict_attrbyvalue(attribute, vendorcode);
2930
2931                         /*
2932                          *      If it's NOT continued, AND we know
2933                          *      about it, AND it's not a TLV, we can
2934                          *      create a normal pair.
2935                          */
2936                         if (((vsa_ptr[2] & 0x80) == 0) &&
2937                             da && (da->type != PW_TYPE_TLV)) goto create_pair;
2938
2939                         /*
2940                          *      Else it IS continued, or it's a TLV.
2941                          *      Go do a lot of work to find the stuff.
2942                          */
2943                         pair = rad_continuation2vp(packet, original, secret,
2944                                                    attribute, vendorcode,
2945                                                    attrlen, ptr,
2946                                                    packet_length,
2947                                                    ((vsa_ptr[2] & 0x80) != 0),
2948                                                    da);
2949                         goto created_pair;
2950                 }
2951
2952                 /*
2953                  *      Create the attribute, setting the default type
2954                  *      to 'octets'.  If the type in the dictionary
2955                  *      is different, then the dictionary type will
2956                  *      over-ride this one.
2957                  *
2958                  *      If the attribute has no data, then discard it.
2959                  *
2960                  *      Unless it's CUI.  Damn you, CUI!
2961                  */
2962         create_pair:
2963                 if (!attrlen &&
2964                     (attribute != PW_CHARGEABLE_USER_IDENTITY)) goto next;
2965
2966                 pair = rad_attr2vp(packet, original, secret,
2967                                    attribute, vendorcode, attrlen, ptr);
2968                 if (!pair) {
2969                         pairfree(&packet->vps);
2970                         fr_strerror_printf("out of memory");
2971                         return -1;
2972                 }
2973
2974         created_pair:
2975                 *tail = pair;
2976                 while (pair) {
2977                         num_attributes++;
2978                         debug_pair(pair);
2979                         tail = &pair->next;
2980                         pair = pair->next;
2981                 }
2982
2983                 /*
2984                  *      VSA's may not have been counted properly in
2985                  *      rad_packet_ok() above, as it is hard to count
2986                  *      then without using the dictionary.  We
2987                  *      therefore enforce the limits here, too.
2988                  */
2989                 if ((fr_max_attributes > 0) &&
2990                     (num_attributes > fr_max_attributes)) {
2991                         char host_ipaddr[128];
2992
2993                         pairfree(&packet->vps);
2994                         fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2995                                    inet_ntop(packet->src_ipaddr.af,
2996                                              &packet->src_ipaddr.ipaddr,
2997                                              host_ipaddr, sizeof(host_ipaddr)),
2998                                    num_attributes, fr_max_attributes);
2999                         return -1;
3000                 }
3001
3002         next:
3003                 if (vendorlen == 0) vendorcode = 0;
3004                 ptr += attrlen;
3005                 packet_length -= attrlen;
3006         }
3007
3008         /*
3009          *      Merge information from the outside world into our
3010          *      random pool.
3011          */
3012         fr_rand_seed(packet->data, AUTH_HDR_LEN);
3013
3014         return 0;
3015 }
3016
3017
3018 /*
3019  *      Encode password.
3020  *
3021  *      We assume that the passwd buffer passed is big enough.
3022  *      RFC2138 says the password is max 128 chars, so the size
3023  *      of the passwd buffer must be at least 129 characters.
3024  *      Preferably it's just MAX_STRING_LEN.
3025  *
3026  *      int *pwlen is updated to the new length of the encrypted
3027  *      password - a multiple of 16 bytes.
3028  */
3029 int rad_pwencode(char *passwd, size_t *pwlen, const char *secret,
3030                  const uint8_t *vector)
3031 {
3032         FR_MD5_CTX context, old;
3033         uint8_t digest[AUTH_VECTOR_LEN];
3034         int     i, n, secretlen;
3035         int     len;
3036
3037         /*
3038          *      RFC maximum is 128 bytes.
3039          *
3040          *      If length is zero, pad it out with zeros.
3041          *
3042          *      If the length isn't aligned to 16 bytes,
3043          *      zero out the extra data.
3044          */
3045         len = *pwlen;
3046
3047         if (len > 128) len = 128;
3048
3049         if (len == 0) {
3050                 memset(passwd, 0, AUTH_PASS_LEN);
3051                 len = AUTH_PASS_LEN;
3052         } else if ((len % AUTH_PASS_LEN) != 0) {
3053                 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3054                 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3055         }
3056         *pwlen = len;
3057
3058         /*
3059          *      Use the secret to setup the decryption digest
3060          */
3061         secretlen = strlen(secret);
3062
3063         fr_MD5Init(&context);
3064         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3065         old = context;          /* save intermediate work */
3066
3067         /*
3068          *      Encrypt it in place.  Don't bother checking
3069          *      len, as we've ensured above that it's OK.
3070          */
3071         for (n = 0; n < len; n += AUTH_PASS_LEN) {
3072                 if (n == 0) {
3073                         fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3074                         fr_MD5Final(digest, &context);
3075                 } else {
3076                         context = old;
3077                         fr_MD5Update(&context,
3078                                      (uint8_t *) passwd + n - AUTH_PASS_LEN,
3079                                      AUTH_PASS_LEN);
3080                         fr_MD5Final(digest, &context);
3081                 }
3082
3083                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3084                         passwd[i + n] ^= digest[i];
3085                 }
3086         }
3087
3088         return 0;
3089 }
3090
3091 /*
3092  *      Decode password.
3093  */
3094 int rad_pwdecode(char *passwd, size_t pwlen, const char *secret,
3095                  const uint8_t *vector)
3096 {
3097         FR_MD5_CTX context, old;
3098         uint8_t digest[AUTH_VECTOR_LEN];
3099         int     i;
3100         size_t  n, secretlen;
3101
3102         /*
3103          *      The RFC's say that the maximum is 128.
3104          *      The buffer we're putting it into above is 254, so
3105          *      we don't need to do any length checking.
3106          */
3107         if (pwlen > 128) pwlen = 128;
3108
3109         /*
3110          *      Catch idiots.
3111          */
3112         if (pwlen == 0) goto done;
3113
3114         /*
3115          *      Use the secret to setup the decryption digest
3116          */
3117         secretlen = strlen(secret);
3118
3119         fr_MD5Init(&context);
3120         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3121         old = context;          /* save intermediate work */
3122
3123         /*
3124          *      The inverse of the code above.
3125          */
3126         for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3127                 if (n == 0) {
3128                         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3129                         fr_MD5Final(digest, &context);
3130
3131                         context = old;
3132                         if (pwlen > AUTH_PASS_LEN) {
3133                                 fr_MD5Update(&context, (uint8_t *) passwd,
3134                                              AUTH_PASS_LEN);
3135                         }
3136                 } else {
3137                         fr_MD5Final(digest, &context);
3138
3139                         context = old;
3140                         if (pwlen > (n + AUTH_PASS_LEN)) {
3141                                 fr_MD5Update(&context, (uint8_t *) passwd + n,
3142                                              AUTH_PASS_LEN);
3143                         }
3144                 }
3145
3146                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3147                         passwd[i + n] ^= digest[i];
3148                 }
3149         }
3150
3151  done:
3152         passwd[pwlen] = '\0';
3153         return strlen(passwd);
3154 }
3155
3156
3157 /*
3158  *      Encode Tunnel-Password attributes when sending them out on the wire.
3159  *
3160  *      int *pwlen is updated to the new length of the encrypted
3161  *      password - a multiple of 16 bytes.
3162  *
3163  *      This is per RFC-2868 which adds a two char SALT to the initial intermediate
3164  *      value MD5 hash.
3165  */
3166 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, const char *secret,
3167                         const uint8_t *vector)
3168 {
3169         uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
3170         unsigned char   digest[AUTH_VECTOR_LEN];
3171         char*   salt;
3172         int     i, n, secretlen;
3173         unsigned len, n2;
3174
3175         len = *pwlen;
3176
3177         if (len > 127) len = 127;
3178
3179         /*
3180          * Shift the password 3 positions right to place a salt and original
3181          * length, tag will be added automatically on packet send
3182          */
3183         for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
3184         salt = passwd;
3185         passwd += 2;
3186         /*
3187          * save original password length as first password character;
3188          */
3189         *passwd = len;
3190         len += 1;
3191
3192
3193         /*
3194          *      Generate salt.  The RFC's say:
3195          *
3196          *      The high bit of salt[0] must be set, each salt in a
3197          *      packet should be unique, and they should be random
3198          *
3199          *      So, we set the high bit, add in a counter, and then
3200          *      add in some CSPRNG data.  should be OK..
3201          */
3202         salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
3203                    (fr_rand() & 0x07));
3204         salt[1] = fr_rand();
3205
3206         /*
3207          *      Padd password to multiple of AUTH_PASS_LEN bytes.
3208          */
3209         n = len % AUTH_PASS_LEN;
3210         if (n) {
3211                 n = AUTH_PASS_LEN - n;
3212                 for (; n > 0; n--, len++)
3213                         passwd[len] = 0;
3214         }
3215         /* set new password length */
3216         *pwlen = len + 2;
3217
3218         /*
3219          *      Use the secret to setup the decryption digest
3220          */
3221         secretlen = strlen(secret);
3222         memcpy(buffer, secret, secretlen);
3223
3224         for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
3225                 if (!n2) {
3226                         memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
3227                         memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
3228                         fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
3229                 } else {
3230                         memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
3231                         fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
3232                 }
3233
3234                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3235                         passwd[i + n2] ^= digest[i];
3236                 }
3237         }
3238         passwd[n2] = 0;
3239         return 0;
3240 }
3241
3242 /*
3243  *      Decode Tunnel-Password encrypted attributes.
3244  *
3245  *      Defined in RFC-2868, this uses a two char SALT along with the
3246  *      initial intermediate value, to differentiate it from the
3247  *      above.
3248  */
3249 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, const char *secret,
3250                         const uint8_t *vector)
3251 {
3252         FR_MD5_CTX  context, old;
3253         uint8_t         digest[AUTH_VECTOR_LEN];
3254         int             secretlen;
3255         unsigned        i, n, len, reallen;
3256
3257         len = *pwlen;
3258
3259         /*
3260          *      We need at least a salt.
3261          */
3262         if (len < 2) {
3263                 fr_strerror_printf("tunnel password is too short");
3264                 return -1;
3265         }
3266
3267         /*
3268          *      There's a salt, but no password.  Or, there's a salt
3269          *      and a 'data_len' octet.  It's wrong, but at least we
3270          *      can figure out what it means: the password is empty.
3271          *
3272          *      Note that this means we ignore the 'data_len' field,
3273          *      if the attribute length tells us that there's no
3274          *      more data.  So the 'data_len' field may be wrong,
3275          *      but that's ok...
3276          */
3277         if (len <= 3) {
3278                 passwd[0] = 0;
3279                 *pwlen = 0;
3280                 return 0;
3281         }
3282
3283         len -= 2;               /* discount the salt */
3284
3285         /*
3286          *      Use the secret to setup the decryption digest
3287          */
3288         secretlen = strlen(secret);
3289
3290         fr_MD5Init(&context);
3291         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3292         old = context;          /* save intermediate work */
3293
3294         /*
3295          *      Set up the initial key:
3296          *
3297          *       b(1) = MD5(secret + vector + salt)
3298          */
3299         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3300         fr_MD5Update(&context, passwd, 2);
3301
3302         reallen = 0;
3303         for (n = 0; n < len; n += AUTH_PASS_LEN) {
3304                 int base = 0;
3305
3306                 if (n == 0) {
3307                         fr_MD5Final(digest, &context);
3308
3309                         context = old;
3310
3311                         /*
3312                          *      A quick check: decrypt the first octet
3313                          *      of the password, which is the
3314                          *      'data_len' field.  Ensure it's sane.
3315                          */
3316                         reallen = passwd[2] ^ digest[0];
3317                         if (reallen >= len) {
3318                                 fr_strerror_printf("tunnel password is too long for the attribute");
3319                                 return -1;
3320                         }
3321
3322                         fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
3323
3324                         base = 1;
3325                 } else {
3326                         fr_MD5Final(digest, &context);
3327
3328                         context = old;
3329                         fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
3330                 }
3331
3332                 for (i = base; i < AUTH_PASS_LEN; i++) {
3333                         passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
3334                 }
3335         }
3336
3337         /*
3338          *      See make_tunnel_password, above.
3339          */
3340         if (reallen > 239) reallen = 239;
3341
3342         *pwlen = reallen;
3343         passwd[reallen] = 0;
3344
3345         return reallen;
3346 }
3347
3348 /*
3349  *      Encode a CHAP password
3350  *
3351  *      FIXME: might not work with Ascend because
3352  *      we use vp->length, and Ascend gear likes
3353  *      to send an extra '\0' in the string!
3354  */
3355 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
3356                     VALUE_PAIR *password)
3357 {
3358         int             i;
3359         uint8_t         *ptr;
3360         uint8_t         string[MAX_STRING_LEN * 2 + 1];
3361         VALUE_PAIR      *challenge;
3362
3363         /*
3364          *      Sanity check the input parameters
3365          */
3366         if ((packet == NULL) || (password == NULL)) {
3367                 return -1;
3368         }
3369
3370         /*
3371          *      Note that the password VP can be EITHER
3372          *      a User-Password attribute (from a check-item list),
3373          *      or a CHAP-Password attribute (the client asking
3374          *      the library to encode it).
3375          */
3376
3377         i = 0;
3378         ptr = string;
3379         *ptr++ = id;
3380
3381         i++;
3382         memcpy(ptr, password->vp_strvalue, password->length);
3383         ptr += password->length;
3384         i += password->length;
3385
3386         /*
3387          *      Use Chap-Challenge pair if present,
3388          *      Request-Authenticator otherwise.
3389          */
3390         challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0);
3391         if (challenge) {
3392                 memcpy(ptr, challenge->vp_strvalue, challenge->length);
3393                 i += challenge->length;
3394         } else {
3395                 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
3396                 i += AUTH_VECTOR_LEN;
3397         }
3398
3399         *output = id;
3400         fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
3401
3402         return 0;
3403 }
3404
3405
3406 /*
3407  *      Seed the random number generator.
3408  *
3409  *      May be called any number of times.
3410  */
3411 void fr_rand_seed(const void *data, size_t size)
3412 {
3413         uint32_t hash;
3414
3415         /*
3416          *      Ensure that the pool is initialized.
3417          */
3418         if (!fr_rand_initialized) {
3419                 int fd;
3420
3421                 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
3422
3423                 fd = open("/dev/urandom", O_RDONLY);
3424                 if (fd >= 0) {
3425                         size_t total;
3426                         ssize_t this;
3427
3428                         total = this = 0;
3429                         while (total < sizeof(fr_rand_pool.randrsl)) {
3430                                 this = read(fd, fr_rand_pool.randrsl,
3431                                             sizeof(fr_rand_pool.randrsl) - total);
3432                                 if ((this < 0) && (errno != EINTR)) break;
3433                                 if (this > 0) total += this;
3434                         }
3435                         close(fd);
3436                 } else {
3437                         fr_rand_pool.randrsl[0] = fd;
3438                         fr_rand_pool.randrsl[1] = time(NULL);
3439                         fr_rand_pool.randrsl[2] = errno;
3440                 }
3441
3442                 fr_randinit(&fr_rand_pool, 1);
3443                 fr_rand_pool.randcnt = 0;
3444                 fr_rand_initialized = 1;
3445         }
3446
3447         if (!data) return;
3448
3449         /*
3450          *      Hash the user data
3451          */
3452         hash = fr_rand();
3453         if (!hash) hash = fr_rand();
3454         hash = fr_hash_update(data, size, hash);
3455
3456         fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
3457 }
3458
3459
3460 /*
3461  *      Return a 32-bit random number.
3462  */
3463 uint32_t fr_rand(void)
3464 {
3465         uint32_t num;
3466
3467         /*
3468          *      Ensure that the pool is initialized.
3469          */
3470         if (!fr_rand_initialized) {
3471                 fr_rand_seed(NULL, 0);
3472         }
3473
3474         num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
3475         if (fr_rand_pool.randcnt >= 256) {
3476                 fr_rand_pool.randcnt = 0;
3477                 fr_isaac(&fr_rand_pool);
3478         }
3479
3480         return num;
3481 }
3482
3483
3484 /*
3485  *      Allocate a new RADIUS_PACKET
3486  */
3487 RADIUS_PACKET *rad_alloc(int newvector)
3488 {
3489         RADIUS_PACKET   *rp;
3490
3491         if ((rp = malloc(sizeof(RADIUS_PACKET))) == NULL) {
3492                 fr_strerror_printf("out of memory");
3493                 return NULL;
3494         }
3495         memset(rp, 0, sizeof(*rp));
3496         rp->id = -1;
3497         rp->offset = -1;
3498
3499         if (newvector) {
3500                 int i;
3501                 uint32_t hash, base;
3502
3503                 /*
3504                  *      Don't expose the actual contents of the random
3505                  *      pool.
3506                  */
3507                 base = fr_rand();
3508                 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
3509                         hash = fr_rand() ^ base;
3510                         memcpy(rp->vector + i, &hash, sizeof(hash));
3511                 }
3512         }
3513         fr_rand();              /* stir the pool again */
3514
3515         return rp;
3516 }
3517
3518 RADIUS_PACKET *rad_alloc_reply(RADIUS_PACKET *packet)
3519 {
3520         RADIUS_PACKET *reply;
3521
3522         if (!packet) return NULL;
3523
3524         reply = rad_alloc(0);
3525         if (!reply) return NULL;
3526
3527         /*
3528          *      Initialize the fields from the request.
3529          */
3530         reply->sockfd = packet->sockfd;
3531         reply->dst_ipaddr = packet->src_ipaddr;
3532         reply->src_ipaddr = packet->dst_ipaddr;
3533         reply->dst_port = packet->src_port;
3534         reply->src_port = packet->dst_port;
3535         reply->id = packet->id;
3536         reply->code = 0; /* UNKNOWN code */
3537         memcpy(reply->vector, packet->vector,
3538                sizeof(reply->vector));
3539         reply->vps = NULL;
3540         reply->data = NULL;
3541         reply->data_len = 0;
3542
3543         return reply;
3544 }
3545
3546
3547 /*
3548  *      Free a RADIUS_PACKET
3549  */
3550 void rad_free(RADIUS_PACKET **radius_packet_ptr)
3551 {
3552         RADIUS_PACKET *radius_packet;
3553
3554         if (!radius_packet_ptr || !*radius_packet_ptr) return;
3555         radius_packet = *radius_packet_ptr;
3556
3557         free(radius_packet->data);
3558
3559         pairfree(&radius_packet->vps);
3560
3561         free(radius_packet);
3562
3563         *radius_packet_ptr = NULL;
3564 }