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 int vp2data(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
 640                    const char *secret, const VALUE_PAIR *vp, uint8_t *start,
 641                    size_t room)
 642 {
 643         uint32_t lvalue;
 644         size_t len;
 645         const uint8_t *data;
 646         uint8_t *ptr = start;
 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 -1;
 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 -1;
 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 < 19) return 0;
 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 -1;
 758                         }
 759                         ptr[0] = vp->flags.tag;
 760                         make_tunnel_passwd(ptr + 1, &len, data, len, room - 1,
 761                                            secret, original->vector);
 762                         break;
 763                 case PW_ACCOUNTING_REQUEST:
 764                 case PW_DISCONNECT_REQUEST:
 765                 case PW_COA_REQUEST:
 766                         ptr[0] = vp->flags.tag;
 767                         make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
 768                                            secret, packet->vector);
 769                         break;
 770                 }
 771                 break;
 772
 773                 /*
 774                  *      The code above ensures that this attribute
 775                  *      always fits.
 776                  */
 777         case FLAG_ENCRYPT_ASCEND_SECRET:
 778                 make_secret(ptr, packet->vector, secret, data);
 779                 len = AUTH_VECTOR_LEN;
 780                 break;
 781
 782
 783         default:
 784                 if (vp->flags.has_tag && TAG_VALID(vp->flags.tag)) {
 785                         if (vp->type == PW_TYPE_STRING) {
 786                                 if (len > (room - 1)) len = room - 1;
 787                                 ptr[0] = vp->flags.tag;
 788                                 ptr++;
 789                         } else if (vp->type == PW_TYPE_INTEGER) {
 790                                 array[0] = vp->flags.tag;
 791                         } /* else it can't be any other type */
 792                 }
 793                 memcpy(ptr, data, len);
 794                 break;
 795         } /* switch over encryption flags */
 796
 797         return len + (ptr - start);;
 798 }
 799
 800
 801 static int rad_vp2rfc(const RADIUS_PACKET *packet,
 802                       const RADIUS_PACKET *original,
 803                       const char *secret, const VALUE_PAIR *vp,
 804                       unsigned int attribute, uint8_t *ptr, size_t room)
 805 {
 806         int len;
 807
 808         if (room < 2) return 0;
 809
 810         ptr[0] = attribute & 0xff; /* NOT vp->attribute */
 811         ptr[1] = 2;
 812
 813         len = vp2data(packet, original, secret, vp, ptr + 2, room - 2);
 814         if (len < 0) return len;
 815
 816         ptr[1] += len;
 817
 818         return ptr[1];
 819 }
 820
 821 static int wimax2data(const RADIUS_PACKET *packet,
 822                       const RADIUS_PACKET *original,
 823                       const char *secret, const VALUE_PAIR *vp,
 824                       uint8_t *start, size_t room, uint8_t *ptr)
 825 {
 826         int len;
 827
 828         /*
 829          *      Offsets to Vendor-Specific length, and to length of
 830          *      WiMAX attribute.
 831          */
 832 #define VS_OFF (1)
 833 #define WM_OFF (7)
 834
 835         if (room < 1) return 0;
 836         room--;
 837
 838         /*
 839          *      Account for continuation bytes.  The caller has
 840          *      already accounting for the continuation byte in the
 841          *      Vendor-Specific "length" field.
 842          */
 843         start[WM_OFF]++;
 844         *(ptr++) = 0;
 845
 846         /*
 847          *      Chop everything to fit in one attribute.
 848          */
 849         if (room > (255 - 9)) room = (255 - 9);
 850
 851         /*
 852          *      The attribute contains TLVs that we have NOT decoded
 853          *      properly, OR it contains TLV that the user has encoded
 854          *      manually.  If it has no data, OR it's too long,
 855          *      discard it.  We're not going to walk through its
 856          *      contents trying to figure out how to chop it across
 857          *      multiple continuations.
 858          */
 859         if (vp->flags.has_tlv && (!vp->vp_tlv || (vp->length > room))) {
 860                 return 0;
 861         }
 862
 863         /*
 864          *      The attribute is a top-level integer, ipaddr, etc.
 865          *      Encode it.
 866          */
 867         if (!vp->flags.is_tlv) {
 868                 len = vp2data(packet, original, secret, vp, ptr, room);
 869                 if (len <= 0) return -1;
 870
 871                 start[VS_OFF] += len;
 872                 start[WM_OFF] += len;
 873
 874                 return start[VS_OFF];
 875         }
 876
 877         /*
 878          *      Otherwise it's a TLV.  We need to do more work to
 879          *      encode it.
 880          */
 881
 882         return 0;
 883 }
 884
 885
 886 /*
 887  *      Parse a data structure into a RADIUS attribute.
 888  */
 889 int rad_vp2attr(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
 890                 const char *secret, const VALUE_PAIR *vp, uint8_t *start,
 891                 size_t room)
 892 {
 893         int len;
 894         uint32_t lvalue;
 895         uint8_t *ptr;
 896         DICT_VENDOR *dv;
 897
 898         /*
 899          *      RFC format attributes take the fast path.
 900          */
 901         if (vp->vendor == 0) {
 902                 len = rad_vp2rfc(packet, original, secret, vp,
 903                                  vp->attribute, start, room);
 904                 if (len < 0) return -1;
 905
 906                 /*
 907                  *      RFC 2865 section 5 says that zero-length
 908                  *      attributes MUST NOT be sent.
 909                  *
 910                  *      ... and the WiMAX forum ignores
 911                  *      this... because of one vendor.  Don't they
 912                  *      have anything better to do with their time?
 913                  */
 914                 if ((len == 0) &&
 915                     (vp->attribute != PW_CHARGEABLE_USER_IDENTITY)) return 0;
 916
 917                 return len;
 918
 919         }
 920
 921         /*
 922          *      Not enough room for:
 923          *              attr, len, vendor-id, vsa, vsalen
 924          */
 925         if (room < 8) return 0;
 926
 927         /*
 928          *      Build the Vendor-Specific header
 929          */
 930         ptr = start;
 931         *ptr++ = PW_VENDOR_SPECIFIC;
 932         *ptr++ = 6;
 933         room -= 6;
 934         lvalue = htonl(vp->vendor);
 935         memcpy(ptr, &lvalue, 4);
 936         ptr += 4;
 937
 938         /*
 939          *      Unknown vendors, and type=1,length=1,no-continuation
 940          *      are RFC format attributes.
 941          */
 942         dv = dict_vendorbyvalue(vp->vendor);
 943         if (!dv ||
 944             ((dv->type == 1) && (dv->length = 1) && !dv->flags)) {
 945                 len = rad_vp2rfc(packet, original, secret, vp,
 946                                  vp->attribute, ptr, room);
 947                 if (len <= 0) return len;
 948
 949                 start[1] += len;
 950                 return start[1];
 951         }
 952
 953         if (room < (dv->type + dv->length + dv->flags)) return 0;
 954         room -= (dv->type + dv->length + dv->flags);
 955         start[1] += (dv->type + dv->length + dv->flags);
 956
 957         switch (dv->type) {
 958                 case 1:
 959                         ptr[0] = (vp->attribute & 0xFF);
 960                         break;
 961
 962                 case 2:
 963                         ptr[0] = ((vp->attribute >> 8) & 0xFF);
 964                         ptr[1] = (vp->attribute & 0xFF);
 965                         break;
 966
 967                 case 4:
 968                         ptr[0] = 0;
 969                         ptr[1] = ((vp->attribute >> 16) & 0xFF);
 970                         ptr[2] = ((vp->attribute >> 8) & 0xFF);
 971                         ptr[3] = (vp->attribute & 0xFF);
 972                         break;
 973
 974                 default:
 975                         return 0; /* silently discard it */
 976         }
 977         ptr += dv->type;
 978
 979         switch (dv->length) {
 980         case 0:
 981                 break;
 982         case 1:
 983                 ptr[0] = dv->type + 1;
 984                 break;
 985         case 2:
 986                 ptr[0] = 0;
 987                 ptr[1] = dv->type + 2;
 988                 break;
 989
 990         default:
 991                 return 0; /* silently discard it */
 992         }
 993         ptr += dv->length;
 994
 995         /*
 996          *      WiMAX attributes take their own path through the
 997          *      system.
 998          */
 999         if (dv->flags) return wimax2data(packet, original, secret, vp,
1000                                          start, room, ptr);
1001
1002         len = vp2data(packet, original, secret, vp, ptr, room);
1003         if (len <= 0) return len;
1004
1005         if (dv->length != 0) ptr[-1] += len;
1006
1007         start[1] += len;
1008
1009         return start[1];
1010 }
1011
1012 /*
1013  *  Swap 123a -> 0321
1014  */
1015 #define REORDER(x) ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | ((x & 0xff000000 >> 24))
1016
1017 static int rad_encode_wimax(const RADIUS_PACKET *packet,
1018                             const RADIUS_PACKET *original,
1019                             const char *secret, VALUE_PAIR *reply,
1020                             uint8_t *start, size_t room)
1021 {
1022         int len, total_len = 0;
1023         uint8_t *wimax = NULL;
1024         uint8_t *ptr = start;
1025         uint32_t maxattr;
1026         VALUE_PAIR *vp = reply;
1027
1028         /*
1029          *      Swap the order of the WiMAX hacks, to make later
1030          *      comparisons easier.
1031          */
1032         maxattr = REORDER(vp->attribute);
1033
1034 redo:
1035         len = rad_vp2attr(packet, original, secret, vp, ptr,
1036                           (start + room) - ptr);
1037         if (len <= 0) return total_len;
1038
1039         /*
1040          *      After adding an attribute with the simplest encoding,
1041          *      check to see if we can append it to the previous one.
1042          */
1043         if (wimax) {
1044                 if ((wimax[1] + (ptr[1] - 6)) <= 255) {
1045                         unsigned int hack;
1046
1047                         hack = ptr[7] - 3;
1048                         memmove(ptr, ptr + 9, hack);
1049                         wimax[1] += hack;
1050                         wimax[7] += hack;
1051                         len -= 9;
1052
1053                         /*
1054                          *      See if we can nest sub-TLVs, too, in
1055                          *      order to shorten the encoding.
1056                          */
1057
1058                 } else {
1059                         wimax[8] = 0x80; /* set continuation */
1060                         wimax = ptr;
1061                 }
1062         } else {
1063                 wimax = ptr;
1064         }
1065
1066         total_len += len;
1067         ptr += len;
1068
1069         vp->flags.encoded = 1;
1070         vp = vp->next;
1071
1072         /*
1073          *      Look at the NEXT tlv.  Ensure that we encode
1074          *      attributes into a common VSA *only* if they are for
1075          *      the same WiMAX VSA, AND if the TLVs are in numerically
1076          *      increasing order.
1077          */
1078         if (vp && vp->flags.is_tlv && (reply->vendor == vp->vendor) &&
1079             ((reply->attribute & 0xff) == (vp->attribute & 0xff))) {
1080                 uint32_t attr;
1081
1082                 attr = REORDER(vp->attribute);
1083                 if (attr >= maxattr) {
1084                         maxattr = attr;
1085                         goto redo;
1086                 }
1087         }
1088
1089         return total_len;
1090 }
1091
1092
1093 /*
1094  *      Encode a packet.
1095  */
1096 int rad_encode(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1097                const char *secret)
1098 {
1099         radius_packet_t *hdr;
1100         uint8_t         *ptr;
1101         uint16_t        total_length;
1102         int             len;
1103         VALUE_PAIR      *reply;
1104         const char      *what;
1105         char            ip_buffer[128];
1106
1107         /*
1108          *      A 4K packet, aligned on 64-bits.
1109          */
1110         uint64_t        data[MAX_PACKET_LEN / sizeof(uint64_t)];
1111
1112         if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1113                 what = fr_packet_codes[packet->code];
1114         } else {
1115                 what = "Reply";
1116         }
1117
1118         DEBUG("Sending %s of id %d to %s port %d\n",
1119               what, packet->id,
1120               inet_ntop(packet->dst_ipaddr.af,
1121                         &packet->dst_ipaddr.ipaddr,
1122                         ip_buffer, sizeof(ip_buffer)),
1123               packet->dst_port);
1124
1125         /*
1126          *      Double-check some things based on packet code.
1127          */
1128         switch (packet->code) {
1129         case PW_AUTHENTICATION_ACK:
1130         case PW_AUTHENTICATION_REJECT:
1131         case PW_ACCESS_CHALLENGE:
1132                 if (!original) {
1133                         fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1134                         return -1;
1135                 }
1136                 break;
1137
1138                 /*
1139                  *      These packet vectors start off as all zero.
1140                  */
1141         case PW_ACCOUNTING_REQUEST:
1142         case PW_DISCONNECT_REQUEST:
1143         case PW_COA_REQUEST:
1144                 memset(packet->vector, 0, sizeof(packet->vector));
1145                 break;
1146
1147         default:
1148                 break;
1149         }
1150
1151         /*
1152          *      Use memory on the stack, until we know how
1153          *      large the packet will be.
1154          */
1155         hdr = (radius_packet_t *) data;
1156
1157         /*
1158          *      Build standard header
1159          */
1160         hdr->code = packet->code;
1161         hdr->id = packet->id;
1162
1163         memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1164
1165         total_length = AUTH_HDR_LEN;
1166
1167         /*
1168          *      Load up the configuration values for the user
1169          */
1170         ptr = hdr->data;
1171         packet->offset = 0;
1172
1173         /*
1174          *      FIXME: Loop twice over the reply list.  The first time,
1175          *      calculate the total length of data.  The second time,
1176          *      allocate the memory, and fill in the VP's.
1177          *
1178          *      Hmm... this may be slower than just doing a small
1179          *      memcpy.
1180          */
1181
1182         /*
1183          *      Loop over the reply attributes for the packet.
1184          */
1185         for (reply = packet->vps; reply; reply = reply->next) {
1186                 /*
1187                  *      Ignore non-wire attributes
1188                  */
1189                 if ((reply->vendor == 0) &&
1190                     ((reply->attribute & 0xFFFF) > 0xff)) {
1191 #ifndef NDEBUG
1192                         /*
1193                          *      Permit the admin to send BADLY formatted
1194                          *      attributes with a debug build.
1195                          */
1196                         if (reply->attribute == PW_RAW_ATTRIBUTE) {
1197                                 memcpy(ptr, reply->vp_octets, reply->length);
1198                                 len = reply->length;
1199                                 goto next;
1200                         }
1201 #endif
1202                         continue;
1203                 }
1204
1205                 /*
1206                  *      Set the Message-Authenticator to the correct
1207                  *      length and initial value.
1208                  */
1209                 if (reply->attribute == PW_MESSAGE_AUTHENTICATOR) {
1210                         reply->length = AUTH_VECTOR_LEN;
1211                         memset(reply->vp_strvalue, 0, AUTH_VECTOR_LEN);
1212
1213                         /*
1214                          *      Cache the offset to the
1215                          *      Message-Authenticator
1216                          */
1217                         packet->offset = total_length;
1218                 }
1219
1220                 /*
1221                  *      Print out ONLY the attributes which
1222                  *      we're sending over the wire, and print
1223                  *      them out BEFORE they're encrypted.
1224                  */
1225                 debug_pair(reply);
1226
1227                 /*
1228                  *      Skip attributes that are encoded.
1229                  */
1230                 if (reply->flags.encoded) continue;
1231
1232                 if (reply->flags.is_tlv) {
1233                         len = rad_encode_wimax(packet, original, secret,
1234                                                reply, ptr,
1235                                                ((uint8_t *) data) + sizeof(data) - ptr);
1236                 } else {
1237
1238                         len = rad_vp2attr(packet, original, secret, reply, ptr,
1239                                           ((uint8_t *) data) + sizeof(data) - ptr);
1240                 }
1241
1242                 if (len < 0) return -1;
1243
1244         next:
1245                 ptr += len;
1246                 total_length += len;
1247         } /* done looping over all attributes */
1248
1249         /*
1250          *      Fill in the rest of the fields, and copy the data over
1251          *      from the local stack to the newly allocated memory.
1252          *
1253          *      Yes, all this 'memcpy' is slow, but it means
1254          *      that we only allocate the minimum amount of
1255          *      memory for a request.
1256          */
1257         packet->data_len = total_length;
1258         packet->data = (uint8_t *) malloc(packet->data_len);
1259         if (!packet->data) {
1260                 fr_strerror_printf("Out of memory");
1261                 return -1;
1262         }
1263
1264         memcpy(packet->data, hdr, packet->data_len);
1265         hdr = (radius_packet_t *) packet->data;
1266
1267         total_length = htons(total_length);
1268         memcpy(hdr->length, &total_length, sizeof(total_length));
1269
1270         return 0;
1271 }
1272
1273
1274 /*
1275  *      Sign a previously encoded packet.
1276  */
1277 int rad_sign(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1278              const char *secret)
1279 {
1280         radius_packet_t *hdr = (radius_packet_t *)packet->data;
1281
1282         /*
1283          *      It wasn't assigned an Id, this is bad!
1284          */
1285         if (packet->id < 0) {
1286                 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1287                 return -1;
1288         }
1289
1290         if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1291             (packet->offset < 0)) {
1292                 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1293                 return -1;
1294         }
1295
1296         /*
1297          *      If there's a Message-Authenticator, update it
1298          *      now, BEFORE updating the authentication vector.
1299          */
1300         if (packet->offset > 0) {
1301                 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1302
1303                 switch (packet->code) {
1304                 case PW_ACCOUNTING_REQUEST:
1305                 case PW_ACCOUNTING_RESPONSE:
1306                 case PW_DISCONNECT_REQUEST:
1307                 case PW_DISCONNECT_ACK:
1308                 case PW_DISCONNECT_NAK:
1309                 case PW_COA_REQUEST:
1310                 case PW_COA_ACK:
1311                 case PW_COA_NAK:
1312                         memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1313                         break;
1314
1315                 case PW_AUTHENTICATION_ACK:
1316                 case PW_AUTHENTICATION_REJECT:
1317                 case PW_ACCESS_CHALLENGE:
1318                         if (!original) {
1319                                 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1320                                 return -1;
1321                         }
1322                         memcpy(hdr->vector, original->vector,
1323                                AUTH_VECTOR_LEN);
1324                         break;
1325
1326                 default:        /* others have vector already set to zero */
1327                         break;
1328
1329                 }
1330
1331                 /*
1332                  *      Set the authentication vector to zero,
1333                  *      calculate the signature, and put it
1334                  *      into the Message-Authenticator
1335                  *      attribute.
1336                  */
1337                 fr_hmac_md5(packet->data, packet->data_len,
1338                             (const uint8_t *) secret, strlen(secret),
1339                             calc_auth_vector);
1340                 memcpy(packet->data + packet->offset + 2,
1341                        calc_auth_vector, AUTH_VECTOR_LEN);
1342
1343                 /*
1344                  *      Copy the original request vector back
1345                  *      to the raw packet.
1346                  */
1347                 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1348         }
1349
1350         /*
1351          *      Switch over the packet code, deciding how to
1352          *      sign the packet.
1353          */
1354         switch (packet->code) {
1355                 /*
1356                  *      Request packets are not signed, bur
1357                  *      have a random authentication vector.
1358                  */
1359         case PW_AUTHENTICATION_REQUEST:
1360         case PW_STATUS_SERVER:
1361                 break;
1362
1363                 /*
1364                  *      Reply packets are signed with the
1365                  *      authentication vector of the request.
1366                  */
1367         default:
1368                 {
1369                         uint8_t digest[16];
1370
1371                         FR_MD5_CTX      context;
1372                         fr_MD5Init(&context);
1373                         fr_MD5Update(&context, packet->data, packet->data_len);
1374                         fr_MD5Update(&context, (const uint8_t *) secret,
1375                                      strlen(secret));
1376                         fr_MD5Final(digest, &context);
1377
1378                         memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1379                         memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1380                         break;
1381                 }
1382         }/* switch over packet codes */
1383
1384         return 0;
1385 }
1386
1387 /*
1388  *      Reply to the request.  Also attach
1389  *      reply attribute value pairs and any user message provided.
1390  */
1391 int rad_send(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1392              const char *secret)
1393 {
1394         VALUE_PAIR              *reply;
1395         const char              *what;
1396         char                    ip_buffer[128];
1397
1398         /*
1399          *      Maybe it's a fake packet.  Don't send it.
1400          */
1401         if (!packet || (packet->sockfd < 0)) {
1402                 return 0;
1403         }
1404
1405         if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1406                 what = fr_packet_codes[packet->code];
1407         } else {
1408                 what = "Reply";
1409         }
1410
1411         /*
1412          *  First time through, allocate room for the packet
1413          */
1414         if (!packet->data) {
1415                 /*
1416                  *      Encode the packet.
1417                  */
1418                 if (rad_encode(packet, original, secret) < 0) {
1419                         return -1;
1420                 }
1421
1422                 /*
1423                  *      Re-sign it, including updating the
1424                  *      Message-Authenticator.
1425                  */
1426                 if (rad_sign(packet, original, secret) < 0) {
1427                         return -1;
1428                 }
1429
1430                 /*
1431                  *      If packet->data points to data, then we print out
1432                  *      the VP list again only for debugging.
1433                  */
1434         } else if (fr_debug_flag) {
1435                 DEBUG("Sending %s of id %d to %s port %d\n", what, packet->id,
1436                       inet_ntop(packet->dst_ipaddr.af,
1437                                 &packet->dst_ipaddr.ipaddr,
1438                                 ip_buffer, sizeof(ip_buffer)),
1439                       packet->dst_port);
1440
1441                 for (reply = packet->vps; reply; reply = reply->next) {
1442                         if ((reply->vendor == 0) &&
1443                             ((reply->attribute & 0xFFFF) > 0xff)) continue;
1444                         debug_pair(reply);
1445                 }
1446         }
1447
1448         /*
1449          *      And send it on it's way.
1450          */
1451         return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
1452                           &packet->src_ipaddr, packet->src_port,
1453                           &packet->dst_ipaddr, packet->dst_port);
1454 }
1455
1456 /*
1457  *      Do a comparison of two authentication digests by comparing
1458  *      the FULL digest.  Otehrwise, the server can be subject to
1459  *      timing attacks that allow attackers find a valid message
1460  *      authenticator.
1461  *
1462  *      http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
1463  */
1464 static int digest_cmp(const uint8_t *a, const uint8_t *b, size_t length)
1465 {
1466         int result = 0;
1467         size_t i;
1468
1469         for (i = 0; i < length; i++) {
1470                 result |= a[i] ^ b[i];
1471         }
1472
1473         return result;          /* 0 is OK, !0 is !OK, just like memcmp */
1474 }
1475
1476
1477 /*
1478  *      Validates the requesting client NAS.  Calculates the
1479  *      signature based on the clients private key.
1480  */
1481 static int calc_acctdigest(RADIUS_PACKET *packet, const char *secret)
1482 {
1483         uint8_t         digest[AUTH_VECTOR_LEN];
1484         FR_MD5_CTX              context;
1485
1486         /*
1487          *      Zero out the auth_vector in the received packet.
1488          *      Then append the shared secret to the received packet,
1489          *      and calculate the MD5 sum. This must be the same
1490          *      as the original MD5 sum (packet->vector).
1491          */
1492         memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1493
1494         /*
1495          *  MD5(packet + secret);
1496          */
1497         fr_MD5Init(&context);
1498         fr_MD5Update(&context, packet->data, packet->data_len);
1499         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1500         fr_MD5Final(digest, &context);
1501
1502         /*
1503          *      Return 0 if OK, 2 if not OK.
1504          */
1505         if (digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
1506         return 0;
1507 }
1508
1509
1510 /*
1511  *      Validates the requesting client NAS.  Calculates the
1512  *      signature based on the clients private key.
1513  */
1514 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1515                             const char *secret)
1516 {
1517         uint8_t         calc_digest[AUTH_VECTOR_LEN];
1518         FR_MD5_CTX              context;
1519
1520         /*
1521          *      Very bad!
1522          */
1523         if (original == NULL) {
1524                 return 3;
1525         }
1526
1527         /*
1528          *  Copy the original vector in place.
1529          */
1530         memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
1531
1532         /*
1533          *  MD5(packet + secret);
1534          */
1535         fr_MD5Init(&context);
1536         fr_MD5Update(&context, packet->data, packet->data_len);
1537         fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1538         fr_MD5Final(calc_digest, &context);
1539
1540         /*
1541          *  Copy the packet's vector back to the packet.
1542          */
1543         memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
1544
1545         /*
1546          *      Return 0 if OK, 2 if not OK.
1547          */
1548         if (digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
1549         return 0;
1550 }
1551
1552
1553 /*
1554  *      See if the data pointed to by PTR is a valid RADIUS packet.
1555  *
1556  *      packet is not 'const * const' because we may update data_len,
1557  *      if there's more data in the UDP packet than in the RADIUS packet.
1558  */
1559 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
1560 {
1561         uint8_t                 *attr;
1562         int                     totallen;
1563         int                     count;
1564         radius_packet_t         *hdr;
1565         char                    host_ipaddr[128];
1566         int                     require_ma = 0;
1567         int                     seen_ma = 0;
1568         int                     num_attributes;
1569
1570         /*
1571          *      Check for packets smaller than the packet header.
1572          *
1573          *      RFC 2865, Section 3., subsection 'length' says:
1574          *
1575          *      "The minimum length is 20 ..."
1576          */
1577         if (packet->data_len < AUTH_HDR_LEN) {
1578                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %d < minimum %d)",
1579                            inet_ntop(packet->src_ipaddr.af,
1580                                      &packet->src_ipaddr.ipaddr,
1581                                      host_ipaddr, sizeof(host_ipaddr)),
1582                                    (int) packet->data_len, AUTH_HDR_LEN);
1583                 return 0;
1584         }
1585
1586         /*
1587          *      RFC 2865, Section 3., subsection 'length' says:
1588          *
1589          *      " ... and maximum length is 4096."
1590          */
1591         if (packet->data_len > MAX_PACKET_LEN) {
1592                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (received %d > maximum %d)",
1593                            inet_ntop(packet->src_ipaddr.af,
1594                                      &packet->src_ipaddr.ipaddr,
1595                                      host_ipaddr, sizeof(host_ipaddr)),
1596                                    (int) packet->data_len, MAX_PACKET_LEN);
1597                 return 0;
1598         }
1599
1600         /*
1601          *      Check for packets with mismatched size.
1602          *      i.e. We've received 128 bytes, and the packet header
1603          *      says it's 256 bytes long.
1604          */
1605         totallen = (packet->data[2] << 8) | packet->data[3];
1606         hdr = (radius_packet_t *)packet->data;
1607
1608         /*
1609          *      Code of 0 is not understood.
1610          *      Code of 16 or greate is not understood.
1611          */
1612         if ((hdr->code == 0) ||
1613             (hdr->code >= FR_MAX_PACKET_CODE)) {
1614                 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code%d ",
1615                            inet_ntop(packet->src_ipaddr.af,
1616                                      &packet->src_ipaddr.ipaddr,
1617                                      host_ipaddr, sizeof(host_ipaddr)),
1618                            hdr->code);
1619                 return 0;
1620         }
1621
1622         /*
1623          *      Message-Authenticator is required in Status-Server
1624          *      packets, otherwise they can be trivially forged.
1625          */
1626         if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
1627
1628         /*
1629          *      It's also required if the caller asks for it.
1630          */
1631         if (flags) require_ma = 1;
1632
1633         /*
1634          *      Repeat the length checks.  This time, instead of
1635          *      looking at the data we received, look at the value
1636          *      of the 'length' field inside of the packet.
1637          *
1638          *      Check for packets smaller than the packet header.
1639          *
1640          *      RFC 2865, Section 3., subsection 'length' says:
1641          *
1642          *      "The minimum length is 20 ..."
1643          */
1644         if (totallen < AUTH_HDR_LEN) {
1645                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %d < minimum %d)",
1646                            inet_ntop(packet->src_ipaddr.af,
1647                                      &packet->src_ipaddr.ipaddr,
1648                                      host_ipaddr, sizeof(host_ipaddr)),
1649                            totallen, AUTH_HDR_LEN);
1650                 return 0;
1651         }
1652
1653         /*
1654          *      And again, for the value of the 'length' field.
1655          *
1656          *      RFC 2865, Section 3., subsection 'length' says:
1657          *
1658          *      " ... and maximum length is 4096."
1659          */
1660         if (totallen > MAX_PACKET_LEN) {
1661                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (length %d > maximum %d)",
1662                            inet_ntop(packet->src_ipaddr.af,
1663                                      &packet->src_ipaddr.ipaddr,
1664                                      host_ipaddr, sizeof(host_ipaddr)),
1665                            totallen, MAX_PACKET_LEN);
1666                 return 0;
1667         }
1668
1669         /*
1670          *      RFC 2865, Section 3., subsection 'length' says:
1671          *
1672          *      "If the packet is shorter than the Length field
1673          *      indicates, it MUST be silently discarded."
1674          *
1675          *      i.e. No response to the NAS.
1676          */
1677         if (packet->data_len < totallen) {
1678                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %d octets, packet length says %d",
1679                            inet_ntop(packet->src_ipaddr.af,
1680                                      &packet->src_ipaddr.ipaddr,
1681                                      host_ipaddr, sizeof(host_ipaddr)),
1682                                    (int) packet->data_len, totallen);
1683                 return 0;
1684         }
1685
1686         /*
1687          *      RFC 2865, Section 3., subsection 'length' says:
1688          *
1689          *      "Octets outside the range of the Length field MUST be
1690          *      treated as padding and ignored on reception."
1691          */
1692         if (packet->data_len > totallen) {
1693                 /*
1694                  *      We're shortening the packet below, but just
1695                  *      to be paranoid, zero out the extra data.
1696                  */
1697                 memset(packet->data + totallen, 0, packet->data_len - totallen);
1698                 packet->data_len = totallen;
1699         }
1700
1701         /*
1702          *      Walk through the packet's attributes, ensuring that
1703          *      they add up EXACTLY to the size of the packet.
1704          *
1705          *      If they don't, then the attributes either under-fill
1706          *      or over-fill the packet.  Any parsing of the packet
1707          *      is impossible, and will result in unknown side effects.
1708          *
1709          *      This would ONLY happen with buggy RADIUS implementations,
1710          *      or with an intentional attack.  Either way, we do NOT want
1711          *      to be vulnerable to this problem.
1712          */
1713         attr = hdr->data;
1714         count = totallen - AUTH_HDR_LEN;
1715         num_attributes = 0;
1716
1717         while (count > 0) {
1718                 /*
1719                  *      Attribute number zero is NOT defined.
1720                  */
1721                 if (attr[0] == 0) {
1722                         fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
1723                                    inet_ntop(packet->src_ipaddr.af,
1724                                              &packet->src_ipaddr.ipaddr,
1725                                              host_ipaddr, sizeof(host_ipaddr)));
1726                         return 0;
1727                 }
1728
1729                 /*
1730                  *      Attributes are at LEAST as long as the ID & length
1731                  *      fields.  Anything shorter is an invalid attribute.
1732                  */
1733                 if (attr[1] < 2) {
1734                         fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %d too short",
1735                                    inet_ntop(packet->src_ipaddr.af,
1736                                              &packet->src_ipaddr.ipaddr,
1737                                              host_ipaddr, sizeof(host_ipaddr)),
1738                                    attr[0]);
1739                         return 0;
1740                 }
1741
1742                 /*
1743                  *      Sanity check the attributes for length.
1744                  */
1745                 switch (attr[0]) {
1746                 default:        /* don't do anything by default */
1747                         break;
1748
1749                         /*
1750                          *      If there's an EAP-Message, we require
1751                          *      a Message-Authenticator.
1752                          */
1753                 case PW_EAP_MESSAGE:
1754                         require_ma = 1;
1755                         break;
1756
1757                 case PW_MESSAGE_AUTHENTICATOR:
1758                         if (attr[1] != 2 + AUTH_VECTOR_LEN) {
1759                                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
1760                                            inet_ntop(packet->src_ipaddr.af,
1761                                                      &packet->src_ipaddr.ipaddr,
1762                                                      host_ipaddr, sizeof(host_ipaddr)),
1763                                            attr[1] - 2);
1764                                 return 0;
1765                         }
1766                         seen_ma = 1;
1767                         break;
1768                 }
1769
1770                 /*
1771                  *      FIXME: Look up the base 255 attributes in the
1772                  *      dictionary, and switch over their type.  For
1773                  *      integer/date/ip, the attribute length SHOULD
1774                  *      be 6.
1775                  */
1776                 count -= attr[1];       /* grab the attribute length */
1777                 attr += attr[1];
1778                 num_attributes++;       /* seen one more attribute */
1779         }
1780
1781         /*
1782          *      If the attributes add up to a packet, it's allowed.
1783          *
1784          *      If not, we complain, and throw the packet away.
1785          */
1786         if (count != 0) {
1787                 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
1788                            inet_ntop(packet->src_ipaddr.af,
1789                                      &packet->src_ipaddr.ipaddr,
1790                                      host_ipaddr, sizeof(host_ipaddr)));
1791                 return 0;
1792         }
1793
1794         /*
1795          *      If we're configured to look for a maximum number of
1796          *      attributes, and we've seen more than that maximum,
1797          *      then throw the packet away, as a possible DoS.
1798          */
1799         if ((fr_max_attributes > 0) &&
1800             (num_attributes > fr_max_attributes)) {
1801                 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
1802                            inet_ntop(packet->src_ipaddr.af,
1803                                      &packet->src_ipaddr.ipaddr,
1804                                      host_ipaddr, sizeof(host_ipaddr)),
1805                            num_attributes, fr_max_attributes);
1806                 return 0;
1807         }
1808
1809         /*
1810          *      http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
1811          *
1812          *      A packet with an EAP-Message attribute MUST also have
1813          *      a Message-Authenticator attribute.
1814          *
1815          *      A Message-Authenticator all by itself is OK, though.
1816          *
1817          *      Similarly, Status-Server packets MUST contain
1818          *      Message-Authenticator attributes.
1819          */
1820         if (require_ma && ! seen_ma) {
1821                 fr_strerror_printf("WARNING: Insecure packet from host %s:  Packet does not contain required Message-Authenticator attribute",
1822                            inet_ntop(packet->src_ipaddr.af,
1823                                      &packet->src_ipaddr.ipaddr,
1824                                      host_ipaddr, sizeof(host_ipaddr)));
1825                 return 0;
1826         }
1827
1828         /*
1829          *      Fill RADIUS header fields
1830          */
1831         packet->code = hdr->code;
1832         packet->id = hdr->id;
1833         memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
1834
1835         return 1;
1836 }
1837
1838
1839 /*
1840  *      Receive UDP client requests, and fill in
1841  *      the basics of a RADIUS_PACKET structure.
1842  */
1843 RADIUS_PACKET *rad_recv(int fd, int flags)
1844 {
1845         int sock_flags = 0;
1846         RADIUS_PACKET           *packet;
1847
1848         /*
1849          *      Allocate the new request data structure
1850          */
1851         if ((packet = malloc(sizeof(*packet))) == NULL) {
1852                 fr_strerror_printf("out of memory");
1853                 return NULL;
1854         }
1855         memset(packet, 0, sizeof(*packet));
1856
1857         if (flags & 0x02) {
1858                 sock_flags = MSG_PEEK;
1859                 flags &= ~0x02;
1860         }
1861
1862         packet->data_len = rad_recvfrom(fd, &packet->data, sock_flags,
1863                                         &packet->src_ipaddr, &packet->src_port,
1864                                         &packet->dst_ipaddr, &packet->dst_port);
1865
1866         /*
1867          *      Check for socket errors.
1868          */
1869         if (packet->data_len < 0) {
1870                 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
1871                 /* packet->data is NULL */
1872                 free(packet);
1873                 return NULL;
1874         }
1875
1876         /*
1877          *      If the packet is too big, then rad_recvfrom did NOT
1878          *      allocate memory.  Instead, it just discarded the
1879          *      packet.
1880          */
1881         if (packet->data_len > MAX_PACKET_LEN) {
1882                 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
1883                 /* packet->data is NULL */
1884                 free(packet);
1885                 return NULL;
1886         }
1887
1888         /*
1889          *      Read no data.  Continue.
1890          *      This check is AFTER the MAX_PACKET_LEN check above, because
1891          *      if the packet is larger than MAX_PACKET_LEN, we also have
1892          *      packet->data == NULL
1893          */
1894         if ((packet->data_len == 0) || !packet->data) {
1895                 fr_strerror_printf("Empty packet: Socket is not ready.");
1896                 free(packet);
1897                 return NULL;
1898         }
1899
1900         /*
1901          *      See if it's a well-formed RADIUS packet.
1902          */
1903         if (!rad_packet_ok(packet, flags)) {
1904                 rad_free(&packet);
1905                 return NULL;
1906         }
1907
1908         /*
1909          *      Remember which socket we read the packet from.
1910          */
1911         packet->sockfd = fd;
1912
1913         /*
1914          *      FIXME: Do even more filtering by only permitting
1915          *      certain IP's.  The problem is that we don't know
1916          *      how to do this properly for all possible clients...
1917          */
1918
1919         /*
1920          *      Explicitely set the VP list to empty.
1921          */
1922         packet->vps = NULL;
1923
1924         if (fr_debug_flag) {
1925                 char host_ipaddr[128];
1926
1927                 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1928                         DEBUG("rad_recv: %s packet from host %s port %d",
1929                               fr_packet_codes[packet->code],
1930                               inet_ntop(packet->src_ipaddr.af,
1931                                         &packet->src_ipaddr.ipaddr,
1932                                         host_ipaddr, sizeof(host_ipaddr)),
1933                               packet->src_port);
1934                 } else {
1935                         DEBUG("rad_recv: Packet from host %s port %d code=%d",
1936                               inet_ntop(packet->src_ipaddr.af,
1937                                         &packet->src_ipaddr.ipaddr,
1938                                         host_ipaddr, sizeof(host_ipaddr)),
1939                               packet->src_port,
1940                               packet->code);
1941                 }
1942                 DEBUG(", id=%d, length=%d\n",
1943                       packet->id, (int) packet->data_len);
1944         }
1945
1946         return packet;
1947 }
1948
1949
1950 /*
1951  *      Verify the signature of a packet.
1952  */
1953 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1954                const char *secret)
1955 {
1956         uint8_t                 *ptr;
1957         int                     length;
1958         int                     attrlen;
1959
1960         if (!packet || !packet->data) return -1;
1961
1962         /*
1963          *      Before we allocate memory for the attributes, do more
1964          *      sanity checking.
1965          */
1966         ptr = packet->data + AUTH_HDR_LEN;
1967         length = packet->data_len - AUTH_HDR_LEN;
1968         while (length > 0) {
1969                 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
1970                 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1971
1972                 attrlen = ptr[1];
1973
1974                 switch (ptr[0]) {
1975                 default:        /* don't do anything. */
1976                         break;
1977
1978                         /*
1979                          *      Note that more than one Message-Authenticator
1980                          *      attribute is invalid.
1981                          */
1982                 case PW_MESSAGE_AUTHENTICATOR:
1983                         memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
1984                         memset(&ptr[2], 0, AUTH_VECTOR_LEN);
1985
1986                         switch (packet->code) {
1987                         default:
1988                                 break;
1989
1990                         case PW_ACCOUNTING_REQUEST:
1991                         case PW_ACCOUNTING_RESPONSE:
1992                         case PW_DISCONNECT_REQUEST:
1993                         case PW_DISCONNECT_ACK:
1994                         case PW_DISCONNECT_NAK:
1995                         case PW_COA_REQUEST:
1996                         case PW_COA_ACK:
1997                         case PW_COA_NAK:
1998                                 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1999                                 break;
2000
2001                         case PW_AUTHENTICATION_ACK:
2002                         case PW_AUTHENTICATION_REJECT:
2003                         case PW_ACCESS_CHALLENGE:
2004                                 if (!original) {
2005                                         fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2006                                         return -1;
2007                                 }
2008                                 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2009                                 break;
2010                         }
2011
2012                         fr_hmac_md5(packet->data, packet->data_len,
2013                                     (const uint8_t *) secret, strlen(secret),
2014                                     calc_auth_vector);
2015                         if (digest_cmp(calc_auth_vector, msg_auth_vector,
2016                                    sizeof(calc_auth_vector)) != 0) {
2017                                 char buffer[32];
2018                                 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator!  (Shared secret is incorrect.)",
2019                                            inet_ntop(packet->src_ipaddr.af,
2020                                                      &packet->src_ipaddr.ipaddr,
2021                                                      buffer, sizeof(buffer)));
2022                                 /* Silently drop packet, according to RFC 3579 */
2023                                 return -1;
2024                         } /* else the message authenticator was good */
2025
2026                         /*
2027                          *      Reinitialize Authenticators.
2028                          */
2029                         memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2030                         memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2031                         break;
2032                 } /* switch over the attributes */
2033
2034                 ptr += attrlen;
2035                 length -= attrlen;
2036         } /* loop over the packet, sanity checking the attributes */
2037
2038         /*
2039          *      It looks like a RADIUS packet, but we can't validate
2040          *      the signature.
2041          */
2042         if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2043                 char buffer[32];
2044                 fr_strerror_printf("Received Unknown packet code %d "
2045                            "from client %s port %d: Cannot validate signature.",
2046                            packet->code,
2047                            inet_ntop(packet->src_ipaddr.af,
2048                                      &packet->src_ipaddr.ipaddr,
2049                                      buffer, sizeof(buffer)),
2050                            packet->src_port);
2051                 return -1;
2052         }
2053
2054         /*
2055          *      Calculate and/or verify digest.
2056          */
2057         switch(packet->code) {
2058                 int rcode;
2059                 char buffer[32];
2060
2061                 case PW_AUTHENTICATION_REQUEST:
2062                 case PW_STATUS_SERVER:
2063                         /*
2064                          *      The authentication vector is random
2065                          *      nonsense, invented by the client.
2066                          */
2067                         break;
2068
2069                 case PW_COA_REQUEST:
2070                 case PW_DISCONNECT_REQUEST:
2071                 case PW_ACCOUNTING_REQUEST:
2072                         if (calc_acctdigest(packet, secret) > 1) {
2073                                 fr_strerror_printf("Received %s packet "
2074                                            "from %s with invalid signature!  (Shared secret is incorrect.)",
2075                                            fr_packet_codes[packet->code],
2076                                            inet_ntop(packet->src_ipaddr.af,
2077                                                      &packet->src_ipaddr.ipaddr,
2078                                                      buffer, sizeof(buffer)));
2079                                 return -1;
2080                         }
2081                         break;
2082
2083                         /* Verify the reply digest */
2084                 case PW_AUTHENTICATION_ACK:
2085                 case PW_AUTHENTICATION_REJECT:
2086                 case PW_ACCESS_CHALLENGE:
2087                 case PW_ACCOUNTING_RESPONSE:
2088                 case PW_DISCONNECT_ACK:
2089                 case PW_DISCONNECT_NAK:
2090                 case PW_COA_ACK:
2091                 case PW_COA_NAK:
2092                         rcode = calc_replydigest(packet, original, secret);
2093                         if (rcode > 1) {
2094                                 fr_strerror_printf("Received %s packet "
2095                                            "from client %s port %d with invalid signature (err=%d)!  (Shared secret is incorrect.)",
2096                                            fr_packet_codes[packet->code],
2097                                            inet_ntop(packet->src_ipaddr.af,
2098                                                      &packet->src_ipaddr.ipaddr,
2099                                                      buffer, sizeof(buffer)),
2100                                            packet->src_port,
2101                                            rcode);
2102                                 return -1;
2103                         }
2104                         break;
2105
2106                 default:
2107                         fr_strerror_printf("Received Unknown packet code %d "
2108                                    "from client %s port %d: Cannot validate signature",
2109                                    packet->code,
2110                                    inet_ntop(packet->src_ipaddr.af,
2111                                              &packet->src_ipaddr.ipaddr,
2112                                                      buffer, sizeof(buffer)),
2113                                    packet->src_port);
2114                         return -1;
2115         }
2116
2117         return 0;
2118 }
2119
2120
2121 static VALUE_PAIR *data2vp(const RADIUS_PACKET *packet,
2122                            const RADIUS_PACKET *original,
2123                            const char *secret, size_t length,
2124                            const uint8_t *data, VALUE_PAIR *vp)
2125 {
2126         int offset = 0;
2127
2128         /*
2129          *      If length is greater than 253, something is SERIOUSLY
2130          *      wrong.
2131          */
2132         if (length > 253) length = 253; /* paranoia (pair-anoia?) */
2133
2134         vp->length = length;
2135         vp->operator = T_OP_EQ;
2136         vp->next = NULL;
2137
2138         /*
2139          *      Handle tags.
2140          */
2141         if (vp->flags.has_tag) {
2142                 if (TAG_VALID(data[0]) ||
2143                     (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD)) {
2144                         /*
2145                          *      Tunnel passwords REQUIRE a tag, even
2146                          *      if don't have a valid tag.
2147                          */
2148                         vp->flags.tag = data[0];
2149
2150                         if ((vp->type == PW_TYPE_STRING) ||
2151                             (vp->type == PW_TYPE_OCTETS)) offset = 1;
2152                 }
2153         }
2154
2155         /*
2156          *      Copy the data to be decrypted
2157          */
2158         memcpy(&vp->vp_octets[0], data + offset, length - offset);
2159         vp->length -= offset;
2160
2161         /*
2162          *      Decrypt the attribute.
2163          */
2164         switch (vp->flags.encrypt) {
2165                 /*
2166                  *  User-Password
2167                  */
2168         case FLAG_ENCRYPT_USER_PASSWORD:
2169                 if (original) {
2170                         rad_pwdecode((char *)vp->vp_strvalue,
2171                                      vp->length, secret,
2172                                      original->vector);
2173                 } else {
2174                         rad_pwdecode((char *)vp->vp_strvalue,
2175                                      vp->length, secret,
2176                                      packet->vector);
2177                 }
2178                 if (vp->attribute == PW_USER_PASSWORD) {
2179                         vp->length = strlen(vp->vp_strvalue);
2180                 }
2181                 break;
2182
2183                 /*
2184                  *      Tunnel-Password's may go ONLY
2185                  *      in response packets.
2186                  */
2187         case FLAG_ENCRYPT_TUNNEL_PASSWORD:
2188                 if (!original) goto raw;
2189
2190                 if (rad_tunnel_pwdecode(vp->vp_octets, &vp->length,
2191                                         secret, original->vector) < 0) {
2192                         goto raw;
2193                 }
2194                 break;
2195
2196                 /*
2197                  *  Ascend-Send-Secret
2198                  *  Ascend-Receive-Secret
2199                  */
2200         case FLAG_ENCRYPT_ASCEND_SECRET:
2201                 if (!original) {
2202                         goto raw;
2203                 } else {
2204                         uint8_t my_digest[AUTH_VECTOR_LEN];
2205                         make_secret(my_digest,
2206                                     original->vector,
2207                                     secret, data);
2208                         memcpy(vp->vp_strvalue, my_digest,
2209                                AUTH_VECTOR_LEN );
2210                         vp->vp_strvalue[AUTH_VECTOR_LEN] = '\0';
2211                         vp->length = strlen(vp->vp_strvalue);
2212                 }
2213                 break;
2214
2215         default:
2216                 break;
2217         } /* switch over encryption flags */
2218
2219
2220         switch (vp->type) {
2221         case PW_TYPE_STRING:
2222         case PW_TYPE_OCTETS:
2223         case PW_TYPE_ABINARY:
2224                 /* nothing more to do */
2225                 break;
2226
2227         case PW_TYPE_BYTE:
2228                 if (vp->length != 1) goto raw;
2229
2230                 vp->vp_integer = vp->vp_octets[0];
2231                 break;
2232
2233
2234         case PW_TYPE_SHORT:
2235                 if (vp->length != 2) goto raw;
2236
2237                 vp->vp_integer = (vp->vp_octets[0] << 8) | vp->vp_octets[1];
2238                 break;
2239
2240         case PW_TYPE_INTEGER:
2241                 if (vp->length != 4) goto raw;
2242
2243                 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2244                 vp->vp_integer = ntohl(vp->vp_integer);
2245
2246                 if (vp->flags.has_tag) vp->vp_integer &= 0x00ffffff;
2247
2248                 /*
2249                  *      Try to get named VALUEs
2250                  */
2251                 {
2252                         DICT_VALUE *dval;
2253                         dval = dict_valbyattr(vp->attribute, vp->vendor,
2254                                               vp->vp_integer);
2255                         if (dval) {
2256                                 strlcpy(vp->vp_strvalue,
2257                                         dval->name,
2258                                         sizeof(vp->vp_strvalue));
2259                         }
2260                 }
2261                 break;
2262
2263         case PW_TYPE_DATE:
2264                 if (vp->length != 4) goto raw;
2265
2266                 memcpy(&vp->vp_date, vp->vp_octets, 4);
2267                 vp->vp_date = ntohl(vp->vp_date);
2268                 break;
2269
2270
2271         case PW_TYPE_IPADDR:
2272                 if (vp->length != 4) goto raw;
2273
2274                 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2275                 break;
2276
2277                 /*
2278                  *      IPv6 interface ID is 8 octets long.
2279                  */
2280         case PW_TYPE_IFID:
2281                 if (vp->length != 8) goto raw;
2282                 /* vp->vp_ifid == vp->vp_octets */
2283                 break;
2284
2285                 /*
2286                  *      IPv6 addresses are 16 octets long
2287                  */
2288         case PW_TYPE_IPV6ADDR:
2289                 if (vp->length != 16) goto raw;
2290                 /* vp->vp_ipv6addr == vp->vp_octets */
2291                 break;
2292
2293                 /*
2294                  *      IPv6 prefixes are 2 to 18 octets long.
2295                  *
2296                  *      RFC 3162: The first octet is unused.
2297                  *      The second is the length of the prefix
2298                  *      the rest are the prefix data.
2299                  *
2300                  *      The prefix length can have value 0 to 128.
2301                  */
2302         case PW_TYPE_IPV6PREFIX:
2303                 if (vp->length < 2 || vp->length > 18) goto raw;
2304                 if (vp->vp_octets[1] > 128) goto raw;
2305
2306                 /*
2307                  *      FIXME: double-check that
2308                  *      (vp->vp_octets[1] >> 3) matches vp->length + 2
2309                  */
2310                 if (vp->length < 18) {
2311                         memset(vp->vp_octets + vp->length, 0,
2312                                18 - vp->length);
2313                 }
2314                 break;
2315
2316         case PW_TYPE_SIGNED:
2317                 if (vp->length != 4) goto raw;
2318
2319                 /*
2320                  *      Overload vp_integer for ntohl, which takes
2321                  *      uint32_t, not int32_t
2322                  */
2323                 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2324                 vp->vp_integer = ntohl(vp->vp_integer);
2325                 memcpy(&vp->vp_signed, &vp->vp_integer, 4);
2326                 break;
2327
2328         case PW_TYPE_TLV:
2329                 vp->length = length;
2330                 vp->vp_tlv = malloc(length);
2331                 if (!vp->vp_tlv) {
2332                         pairfree(&vp);
2333                         fr_strerror_printf("No memory");
2334                         return NULL;
2335                 }
2336                 memcpy(vp->vp_tlv, data, length);
2337                 break;
2338
2339         case PW_TYPE_COMBO_IP:
2340                 if (vp->length == 4) {
2341                         vp->type = PW_TYPE_IPADDR;
2342                         memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2343                         break;
2344
2345                 } else if (vp->length == 16) {
2346                         vp->type = PW_TYPE_IPV6ADDR;
2347                         /* vp->vp_ipv6addr == vp->vp_octets */
2348                         break;
2349
2350                 }
2351                 /* FALL-THROUGH */
2352
2353         default:
2354         raw:
2355                 vp->type = PW_TYPE_OCTETS;
2356                 vp->length = length;
2357                 memcpy(vp->vp_octets, data, length);
2358
2359
2360                 /*
2361                  *      Ensure there's no encryption or tag stuff,
2362                  *      we just pass the attribute as-is.
2363                  */
2364                 memset(&vp->flags, 0, sizeof(vp->flags));
2365         }
2366
2367         return vp;
2368 }
2369
2370 static void rad_sortvp(VALUE_PAIR **head)
2371 {
2372         int swapped;
2373         VALUE_PAIR *vp, **tail;
2374
2375         /*
2376          *      Walk over the VP's, sorting them in order.  Did I
2377          *      mention that I hate WiMAX continuations?
2378          *
2379          *      And bubble sort!  WTF is up with that?
2380          */
2381         do {
2382                 swapped = 0;
2383                 tail = head;
2384                 while (*tail) {
2385                         vp = *tail;
2386                         if (!vp->next) break;
2387
2388                         if (vp->attribute > vp->next->attribute) {
2389                                 *tail = vp->next;
2390                                 vp->next = (*tail)->next;
2391                                 (*tail)->next = vp;
2392                                 swapped = 1;
2393                         }
2394                         tail = &(vp->next);
2395                 }
2396         } while (swapped);
2397 }
2398
2399
2400 /*
2401  *      Walk the packet, looking for continuations of this attribute.
2402  *
2403  *      This is (worst-case) O(N^2) in the number of RADIUS
2404  *      attributes.  That happens only when perverse clients create
2405  *      continued attributes, AND separate the fragmented portions
2406  *      with a lot of other attributes.
2407  *
2408  *      Sane clients should put the fragments next to each other, in
2409  *      which case this is O(N), in the number of fragments.
2410  */
2411 static uint8_t *rad_coalesce(unsigned int attribute, int vendor,
2412                              size_t length, uint8_t *data,
2413                              size_t packet_length, size_t *ptlv_length)
2414
2415 {
2416         uint32_t lvalue;
2417         size_t tlv_length = length;
2418         uint8_t *ptr, *tlv, *tlv_data;
2419
2420         for (ptr = data + length;
2421              ptr != (data + packet_length);
2422              ptr += ptr[1]) {
2423                 /* FIXME: Check that there are 6 bytes of data here... */
2424                 if ((ptr[0] != PW_VENDOR_SPECIFIC) ||
2425                     (ptr[1] < (2 + 4 + 3)) || /* WiMAX VSA with continuation */
2426                     (ptr[2] != 0) || (ptr[3] != 0) ||  /* our requirement */
2427                     (ptr[4] != ((vendor >> 8) & 0xff)) ||
2428                     (ptr[5] != (vendor & 0xff))) {
2429                         continue;
2430                 }
2431
2432                 memcpy(&lvalue, ptr + 2, 4); /* Vendor Id */
2433                 lvalue = ntohl(lvalue);
2434                 lvalue <<= 16;
2435                 lvalue |= ptr[2 + 4]; /* add in VSA number */
2436                 if (lvalue != attribute) continue;
2437
2438                 /*
2439                  *      If the vendor-length is too small, it's badly
2440                  *      formed, so we stop.
2441                  */
2442                 if ((ptr[2 + 4 + 1]) < 3) break;
2443
2444                 tlv_length += ptr[2 + 4 + 1] - 3;
2445                 if ((ptr[2 + 4 + 1 + 1] & 0x80) == 0) break;
2446         }
2447
2448         tlv = tlv_data = malloc(tlv_length);
2449         if (!tlv_data) return NULL;
2450
2451         memcpy(tlv, data, length);
2452         tlv += length;
2453
2454         /*
2455          *      Now we walk the list again, copying the data over to
2456          *      our newly created memory.
2457          */
2458         for (ptr = data + length;
2459              ptr != (data + packet_length);
2460              ptr += ptr[1]) {
2461                 int this_length;
2462
2463                 if ((ptr[0] != PW_VENDOR_SPECIFIC) ||
2464                     (ptr[1] < (2 + 4 + 3)) || /* WiMAX VSA with continuation */
2465                     (ptr[2] != 0) || (ptr[3] != 0)) { /* our requirement */
2466                         continue;
2467                 }
2468
2469                 memcpy(&lvalue, ptr + 2, 4);
2470                 lvalue = ntohl(lvalue);
2471                 lvalue <<= 16;
2472                 lvalue |= ptr[2 + 4];
2473                 if (lvalue != attribute) continue;
2474
2475                 /*
2476                  *      If the vendor-length is too small, it's badly
2477                  *      formed, so we stop.
2478                  */
2479                 if ((ptr[2 + 4 + 1]) < 3) break;
2480
2481                 this_length = ptr[2 + 4 + 1] - 3;
2482                 memcpy(tlv, ptr + 2 + 4 + 3, this_length);
2483                 tlv += this_length;
2484
2485                 ptr[2 + 4] = 0; /* What a hack! */
2486                 if ((ptr[2 + 4 + 1 + 1] & 0x80) == 0) break;
2487         }
2488
2489         *ptlv_length = tlv_length;
2490         return tlv_data;
2491 }
2492
2493 /*
2494  *      Walk over Evil WIMAX Hell, creating attributes.
2495  *
2496  *      Won't someone think of the children?  What if they read this code?
2497  */
2498 static VALUE_PAIR *recurse_evil(const RADIUS_PACKET *packet,
2499                                 const RADIUS_PACKET *original,
2500                                 const char *secret,
2501                                 int attribute, int vendor,
2502                                 uint8_t *ptr, size_t len)
2503 {
2504         VALUE_PAIR *head = NULL;
2505         VALUE_PAIR **tail = &head;
2506         VALUE_PAIR *vp;
2507         uint8_t *y;             /* why do I need to do this? */
2508
2509         /*
2510          *      Sanity check the attribute.
2511          */
2512         for (y = ptr; y < (ptr + len); y += y[1]) {
2513                 if ((y[0] == 0) || ((y + 2) > (ptr + len)) ||
2514                     (y[1] < 2) || ((y + y[1]) > (ptr + len))) {
2515                         return NULL;
2516                 }
2517         }
2518
2519         for (y = ptr; y < (ptr + len); y += y[1]) {
2520                 vp = paircreate(attribute | (ptr[0] << 16), vendor,
2521                                 PW_TYPE_OCTETS);
2522                 if (!vp) {
2523                 error:
2524                         pairfree(&head);
2525                         return NULL;
2526                 }
2527
2528                 if (!data2vp(packet, original, secret,
2529                              y[1] - 2, y + 2, vp)) {
2530                         goto error;
2531                 }
2532
2533                 *tail = vp;
2534                 tail = &(vp->next);
2535         }
2536
2537         return head;
2538 }
2539
2540 /*
2541  *      Start at the *data* portion of a continued attribute.  search
2542  *      through the rest of the attributes to find a matching one, and
2543  *      add it's contents to our contents.
2544  */
2545 static VALUE_PAIR *rad_continuation2vp(const RADIUS_PACKET *packet,
2546                                        const RADIUS_PACKET *original,
2547                                        const char *secret, int attribute,
2548                                        int vendor,
2549                                        int length, /* CANNOT be zero */
2550                                        uint8_t *data, size_t packet_length,
2551                                        int flag, DICT_ATTR *da)
2552 {
2553         size_t tlv_length, left;
2554         uint8_t *ptr;
2555         uint8_t *tlv_data;
2556         VALUE_PAIR *vp, *head, **tail;
2557         DICT_ATTR *tlv_da;
2558
2559         /*
2560          *      Ensure we have data that hasn't been split across
2561          *      multiple attributes.
2562          */
2563         if (flag) {
2564                 tlv_data = rad_coalesce(attribute, vendor, length,
2565                                         data, packet_length, &tlv_length);
2566                 if (!tlv_data) return NULL;
2567         } else {
2568                 tlv_data = data;
2569                 tlv_length = length;
2570         }
2571
2572         /*
2573          *      Non-TLV types cannot be continued across multiple
2574          *      attributes.  This is true even of keys that are
2575          *      encrypted with the tunnel-password method.  The spec
2576          *      says that they can be continued... but also that the
2577          *      keys are 160 bits, which means that they CANNOT be
2578          *      continued.  <sigh>
2579          *
2580          *      Note that we don't check "flag" here.  The calling
2581          *      code ensures that
2582          */
2583         if (!da || (da->type != PW_TYPE_TLV)) {
2584         not_well_formed:
2585                 if (tlv_data == data) { /* true if we had 'goto' */
2586                         tlv_data = malloc(tlv_length);
2587                         if (!tlv_data) return NULL;
2588                         memcpy(tlv_data, data, tlv_length);
2589                 }
2590
2591                 vp = paircreate(attribute, vendor, PW_TYPE_OCTETS);
2592                 if (!vp) return NULL;
2593
2594                 vp->type = PW_TYPE_TLV;
2595                 vp->flags.encrypt = FLAG_ENCRYPT_NONE;
2596                 vp->flags.has_tag = 0;
2597                 vp->flags.is_tlv = 0;
2598                 vp->vp_tlv = tlv_data;
2599                 vp->length = tlv_length;
2600                 return vp;
2601         } /* else it WAS a TLV, go decode the sub-tlv's */
2602
2603         /*
2604          *      Now (sigh) we walk over the TLV, seeing if it is
2605          *      well-formed.
2606          */
2607         left = tlv_length;
2608         for (ptr = tlv_data;
2609              ptr != (tlv_data + tlv_length);
2610              ptr += ptr[1]) {
2611                 if ((left < 2) ||
2612                     (ptr[1] < 2) ||
2613                     (ptr[1] > left)) {
2614                         goto not_well_formed;
2615                 }
2616
2617                 left -= ptr[1];
2618         }
2619
2620         /*
2621          *      Now we walk over the TLV *again*, creating sub-tlv's.
2622          */
2623         head = NULL;
2624         tail = &head;
2625
2626         for (ptr = tlv_data;
2627              ptr != (tlv_data + tlv_length);
2628              ptr += ptr[1]) {
2629
2630                 tlv_da = dict_attrbyvalue(attribute | (ptr[0] << 8), vendor);
2631                 if (tlv_da && (tlv_da->type == PW_TYPE_TLV)) {
2632                         vp = recurse_evil(packet, original, secret,
2633                                           attribute | (ptr[0] << 8),
2634                                           vendor, ptr + 2, ptr[1] - 2);
2635
2636                         if (!vp) {
2637                                 pairfree(&head);
2638                                 goto not_well_formed;
2639                         }
2640                 } else {
2641                         vp = paircreate(attribute | (ptr[0] << 8), vendor,
2642                                         PW_TYPE_OCTETS);
2643                         if (!vp) {
2644                                 pairfree(&head);
2645                                 goto not_well_formed;
2646                         }
2647
2648                         if (!data2vp(packet, original, secret,
2649                                      ptr[1] - 2, ptr + 2, vp)) {
2650                                 pairfree(&head);
2651                                 goto not_well_formed;
2652                         }
2653                 }
2654
2655                 *tail = vp;
2656
2657                 while (*tail) tail = &((*tail)->next);
2658         }
2659
2660         /*
2661          *      TLV's MAY be continued, but sometimes they're not.
2662          */
2663         if (tlv_data != data) free(tlv_data);
2664
2665         if (head->next) rad_sortvp(&head);
2666
2667         return head;
2668 }
2669
2670
2671 /*
2672  *      Parse a RADIUS attribute into a data structure.
2673  */
2674 VALUE_PAIR *rad_attr2vp(const RADIUS_PACKET *packet,
2675                         const RADIUS_PACKET *original,
2676                         const char *secret, int attribute, int vendor,
2677                         int length, const uint8_t *data)
2678 {
2679         VALUE_PAIR *vp;
2680
2681         vp = paircreate(attribute, vendor, PW_TYPE_OCTETS);
2682         if (!vp) return NULL;
2683
2684         return data2vp(packet, original, secret, length, data, vp);
2685 }
2686
2687
2688 /*
2689  *      Calculate/check digest, and decode radius attributes.
2690  *      Returns:
2691  *      -1 on decoding error
2692  *      0 on success
2693  */
2694 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2695                const char *secret)
2696 {
2697         uint32_t                lvalue;
2698         uint32_t                vendorcode;
2699         VALUE_PAIR              **tail;
2700         VALUE_PAIR              *pair;
2701         uint8_t                 *ptr, *vsa_ptr;
2702         int                     packet_length;
2703         int                     attribute;
2704         int                     attrlen;
2705         int                     vendorlen;
2706         radius_packet_t         *hdr;
2707         int                     vsa_tlen, vsa_llen, vsa_offset;
2708         DICT_VENDOR             *dv = NULL;
2709         int                     num_attributes = 0;
2710
2711         /*
2712          *      Extract attribute-value pairs
2713          */
2714         hdr = (radius_packet_t *)packet->data;
2715         ptr = hdr->data;
2716         packet_length = packet->data_len - AUTH_HDR_LEN;
2717
2718         /*
2719          *      There may be VP's already in the packet.  Don't
2720          *      destroy them.
2721          */
2722         for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
2723                 /* nothing */
2724         }
2725
2726         vendorcode = 0;
2727         vendorlen  = 0;
2728         vsa_tlen = vsa_llen = 1;
2729         vsa_offset = 0;
2730
2731         /*
2732          *      We have to read at least two bytes.
2733          *
2734          *      rad_recv() above ensures that this is OK.
2735          */
2736         while (packet_length > 0) {
2737                 attribute = -1;
2738                 attrlen = -1;
2739
2740                 /*
2741                  *      Normal attribute, handle it like normal.
2742                  */
2743                 if (vendorcode == 0) {
2744                         /*
2745                          *      No room to read attr/length,
2746                          *      or bad attribute, or attribute is
2747                          *      too short, or attribute is too long,
2748                          *      stop processing the packet.
2749                          */
2750                         if ((packet_length < 2) ||
2751                             (ptr[0] == 0) ||  (ptr[1] < 2) ||
2752                             (ptr[1] > packet_length)) break;
2753
2754                         attribute = *ptr++;
2755                         attrlen   = *ptr++;
2756
2757                         attrlen -= 2;
2758                         packet_length  -= 2;
2759
2760                         if (attribute != PW_VENDOR_SPECIFIC) goto create_pair;
2761
2762                         /*
2763                          *      No vendor code, or ONLY vendor code.
2764                          */
2765                         if (attrlen <= 4) goto create_pair;
2766
2767                         vendorlen = 0;
2768                 }
2769
2770                 /*
2771                  *      Handle Vendor-Specific
2772                  */
2773                 if (vendorlen == 0) {
2774                         uint8_t *subptr;
2775                         int sublen;
2776                         int myvendor;
2777
2778                         /*
2779                          *      attrlen was checked above.
2780                          */
2781                         memcpy(&lvalue, ptr, 4);
2782                         myvendor = ntohl(lvalue);
2783
2784                         /*
2785                          *      Zero isn't allowed.
2786                          */
2787                         if (myvendor == 0) goto create_pair;
2788
2789                         /*
2790                          *      This is an implementation issue.
2791                          *      We currently pack vendor into the upper
2792                          *      16 bits of a 32-bit attribute number,
2793                          *      so we can't handle vendor numbers larger
2794                          *      than 16 bits.
2795                          */
2796                         if (myvendor > 65535) goto create_pair;
2797
2798                         vsa_tlen = vsa_llen = 1;
2799                         vsa_offset = 0;
2800                         dv = dict_vendorbyvalue(myvendor);
2801                         if (dv) {
2802                                 vsa_tlen = dv->type;
2803                                 vsa_llen = dv->length;
2804                                 if (dv->flags) vsa_offset = 1;
2805                         }
2806
2807                         /*
2808                          *      Sweep through the list of VSA's,
2809                          *      seeing if they exactly fill the
2810                          *      outer Vendor-Specific attribute.
2811                          *
2812                          *      If not, create a raw Vendor-Specific.
2813                          */
2814                         subptr = ptr + 4;
2815                         sublen = attrlen - 4;
2816
2817                         /*
2818                          *      See if we can parse it.
2819                          */
2820                         do {
2821                                 int myattr = 0;
2822
2823                                 /*
2824                                  *      Not enough room for one more
2825                                  *      attribute.  Die!
2826                                  */
2827                                 if (sublen < (vsa_tlen + vsa_llen + vsa_offset)) goto create_pair;
2828
2829                                 /*
2830                                  *      Ensure that the attribute number
2831                                  *      is OK.
2832                                  */
2833                                 switch (vsa_tlen) {
2834                                 case 1:
2835                                         myattr = subptr[0];
2836                                         break;
2837
2838                                 case 2:
2839                                         myattr = (subptr[0] << 8) | subptr[1];
2840                                         break;
2841
2842                                 case 4:
2843                                         if ((subptr[0] != 0) ||
2844                                             (subptr[1] != 0)) goto create_pair;
2845
2846                                         myattr = (subptr[2] << 8) | subptr[3];
2847                                         break;
2848
2849                                         /*
2850                                          *      Our dictionary is broken.
2851                                          */
2852                                 default:
2853                                         goto create_pair;
2854                                 }
2855
2856                                 switch (vsa_llen) {
2857                                 case 0:
2858                                         attribute = myattr;
2859                                         ptr += 4 + vsa_tlen;
2860                                         attrlen -= (4 + vsa_tlen);
2861                                         packet_length -= 4 + vsa_tlen;
2862                                         goto create_pair;
2863
2864                                 case 1:
2865                                         if (subptr[vsa_tlen] < (vsa_tlen + vsa_llen + vsa_offset))
2866                                                 goto create_pair;
2867
2868                                         if (subptr[vsa_tlen] > sublen)
2869                                                 goto create_pair;
2870
2871                                         /*
2872                                          *      WiMAX: 0bCrrrrrrr
2873                                          *      Reserved bits MUST be
2874                                          *      zero.
2875                                          */
2876                                         if (vsa_offset &&
2877                                             ((subptr[vsa_tlen + vsa_llen] & 0x7f) != 0))
2878                                                 goto create_pair;
2879
2880                                         sublen -= subptr[vsa_tlen];
2881                                         subptr += subptr[vsa_tlen];
2882                                         break;
2883
2884                                 case 2:
2885                                         if (subptr[vsa_tlen] != 0) goto create_pair;
2886                                         if (subptr[vsa_tlen + 1] < (vsa_tlen + vsa_llen))
2887                                                 goto create_pair;
2888                                         if (subptr[vsa_tlen + 1] > sublen)
2889                                                 goto create_pair;
2890                                         sublen -= subptr[vsa_tlen + 1];
2891                                         subptr += subptr[vsa_tlen + 1];
2892                                         break;
2893
2894                                         /*
2895                                          *      Our dictionaries are
2896                                          *      broken.
2897                                          */
2898                                 default:
2899                                         goto create_pair;
2900                                 }
2901                         } while (sublen > 0);
2902
2903                         vendorcode = myvendor;
2904                         vendorlen = attrlen - 4;
2905                         packet_length -= 4;
2906
2907                         ptr += 4;
2908                 }
2909
2910                 /*
2911                  *      attrlen is the length of this attribute.
2912                  *      total_len is the length of the encompassing
2913                  *      attribute.
2914                  */
2915                 switch (vsa_tlen) {
2916                 case 1:
2917                         attribute = ptr[0];
2918                         break;
2919
2920                 case 2:
2921                         attribute = (ptr[0] << 8) | ptr[1];
2922                         break;
2923
2924                 default:        /* can't hit this. */
2925                         return -1;
2926                 }
2927                 vsa_ptr = ptr;
2928                 ptr += vsa_tlen;
2929
2930                 switch (vsa_llen) {
2931                 case 1:
2932                         attrlen = ptr[0] - (vsa_tlen + vsa_llen + vsa_offset);
2933                         break;
2934
2935                 case 2:
2936                         attrlen = ptr[1] - (vsa_tlen + vsa_llen);
2937                         break;
2938
2939                 default:        /* can't hit this. */
2940                         return -1;
2941                 }
2942
2943                 ptr += vsa_llen + vsa_offset;
2944                 vendorlen -= vsa_tlen + vsa_llen + vsa_offset + attrlen;
2945                 packet_length -= (vsa_tlen + vsa_llen + vsa_offset);
2946
2947                 /*
2948                  *      Ignore VSAs that have no data.
2949                  */
2950                 if (attrlen == 0) goto next;
2951
2952                 /*
2953                  *      WiMAX attributes of type 0 are ignored.  They
2954                  *      are a secret flag to us that the attribute has
2955                  *      already been dealt with.
2956                  */
2957                 if ((vendorcode == VENDORPEC_WIMAX) && (attribute == 0)) {
2958                         goto next;
2959                 }
2960
2961                 if (vsa_offset) {
2962                         DICT_ATTR *da;
2963
2964                         da = dict_attrbyvalue(attribute, vendorcode);
2965
2966                         /*
2967                          *      If it's NOT continued, AND we know
2968                          *      about it, AND it's not a TLV, we can
2969                          *      create a normal pair.
2970                          */
2971                         if (((vsa_ptr[2] & 0x80) == 0) &&
2972                             da && (da->type != PW_TYPE_TLV)) goto create_pair;
2973
2974                         /*
2975                          *      Else it IS continued, or it's a TLV.
2976                          *      Go do a lot of work to find the stuff.
2977                          */
2978                         pair = rad_continuation2vp(packet, original, secret,
2979                                                    attribute, vendorcode,
2980                                                    attrlen, ptr,
2981                                                    packet_length,
2982                                                    ((vsa_ptr[2] & 0x80) != 0),
2983                                                    da);
2984                         goto created_pair;
2985                 }
2986
2987                 /*
2988                  *      Create the attribute, setting the default type
2989                  *      to 'octets'.  If the type in the dictionary
2990                  *      is different, then the dictionary type will
2991                  *      over-ride this one.
2992                  *
2993                  *      If the attribute has no data, then discard it.
2994                  *
2995                  *      Unless it's CUI.  Damn you, CUI!
2996                  */
2997         create_pair:
2998                 if (!attrlen &&
2999                     (attribute != PW_CHARGEABLE_USER_IDENTITY)) goto next;
3000
3001                 pair = rad_attr2vp(packet, original, secret,
3002                                    attribute, vendorcode, attrlen, ptr);
3003                 if (!pair) {
3004                         pairfree(&packet->vps);
3005                         fr_strerror_printf("out of memory");
3006                         return -1;
3007                 }
3008
3009         created_pair:
3010                 *tail = pair;
3011                 while (pair) {
3012                         num_attributes++;
3013                         debug_pair(pair);
3014                         tail = &pair->next;
3015                         pair = pair->next;
3016                 }
3017
3018                 /*
3019                  *      VSA's may not have been counted properly in
3020                  *      rad_packet_ok() above, as it is hard to count
3021                  *      then without using the dictionary.  We
3022                  *      therefore enforce the limits here, too.
3023                  */
3024                 if ((fr_max_attributes > 0) &&
3025                     (num_attributes > fr_max_attributes)) {
3026                         char host_ipaddr[128];
3027
3028                         pairfree(&packet->vps);
3029                         fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
3030                                    inet_ntop(packet->src_ipaddr.af,
3031                                              &packet->src_ipaddr.ipaddr,
3032                                              host_ipaddr, sizeof(host_ipaddr)),
3033                                    num_attributes, fr_max_attributes);
3034                         return -1;
3035                 }
3036
3037         next:
3038                 if (vendorlen == 0) vendorcode = 0;
3039                 ptr += attrlen;
3040                 packet_length -= attrlen;
3041         }
3042
3043         /*
3044          *      Merge information from the outside world into our
3045          *      random pool.
3046          */
3047         fr_rand_seed(packet->data, AUTH_HDR_LEN);
3048
3049         return 0;
3050 }
3051
3052
3053 /*
3054  *      Encode password.
3055  *
3056  *      We assume that the passwd buffer passed is big enough.
3057  *      RFC2138 says the password is max 128 chars, so the size
3058  *      of the passwd buffer must be at least 129 characters.
3059  *      Preferably it's just MAX_STRING_LEN.
3060  *
3061  *      int *pwlen is updated to the new length of the encrypted
3062  *      password - a multiple of 16 bytes.
3063  */
3064 int rad_pwencode(char *passwd, size_t *pwlen, const char *secret,
3065                  const uint8_t *vector)
3066 {
3067         FR_MD5_CTX context, old;
3068         uint8_t digest[AUTH_VECTOR_LEN];
3069         int     i, n, secretlen;
3070         int     len;
3071
3072         /*
3073          *      RFC maximum is 128 bytes.
3074          *
3075          *      If length is zero, pad it out with zeros.
3076          *
3077          *      If the length isn't aligned to 16 bytes,
3078          *      zero out the extra data.
3079          */
3080         len = *pwlen;
3081
3082         if (len > 128) len = 128;
3083
3084         if (len == 0) {
3085                 memset(passwd, 0, AUTH_PASS_LEN);
3086                 len = AUTH_PASS_LEN;
3087         } else if ((len % AUTH_PASS_LEN) != 0) {
3088                 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3089                 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3090         }
3091         *pwlen = len;
3092
3093         /*
3094          *      Use the secret to setup the decryption digest
3095          */
3096         secretlen = strlen(secret);
3097
3098         fr_MD5Init(&context);
3099         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3100         old = context;          /* save intermediate work */
3101
3102         /*
3103          *      Encrypt it in place.  Don't bother checking
3104          *      len, as we've ensured above that it's OK.
3105          */
3106         for (n = 0; n < len; n += AUTH_PASS_LEN) {
3107                 if (n == 0) {
3108                         fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3109                         fr_MD5Final(digest, &context);
3110                 } else {
3111                         context = old;
3112                         fr_MD5Update(&context,
3113                                      (uint8_t *) passwd + n - AUTH_PASS_LEN,
3114                                      AUTH_PASS_LEN);
3115                         fr_MD5Final(digest, &context);
3116                 }
3117
3118                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3119                         passwd[i + n] ^= digest[i];
3120                 }
3121         }
3122
3123         return 0;
3124 }
3125
3126 /*
3127  *      Decode password.
3128  */
3129 int rad_pwdecode(char *passwd, size_t pwlen, const char *secret,
3130                  const uint8_t *vector)
3131 {
3132         FR_MD5_CTX context, old;
3133         uint8_t digest[AUTH_VECTOR_LEN];
3134         int     i;
3135         size_t  n, secretlen;
3136
3137         /*
3138          *      The RFC's say that the maximum is 128.
3139          *      The buffer we're putting it into above is 254, so
3140          *      we don't need to do any length checking.
3141          */
3142         if (pwlen > 128) pwlen = 128;
3143
3144         /*
3145          *      Catch idiots.
3146          */
3147         if (pwlen == 0) goto done;
3148
3149         /*
3150          *      Use the secret to setup the decryption digest
3151          */
3152         secretlen = strlen(secret);
3153
3154         fr_MD5Init(&context);
3155         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3156         old = context;          /* save intermediate work */
3157
3158         /*
3159          *      The inverse of the code above.
3160          */
3161         for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3162                 if (n == 0) {
3163                         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3164                         fr_MD5Final(digest, &context);
3165
3166                         context = old;
3167                         if (pwlen > AUTH_PASS_LEN) {
3168                                 fr_MD5Update(&context, (uint8_t *) passwd,
3169                                              AUTH_PASS_LEN);
3170                         }
3171                 } else {
3172                         fr_MD5Final(digest, &context);
3173
3174                         context = old;
3175                         if (pwlen > (n + AUTH_PASS_LEN)) {
3176                                 fr_MD5Update(&context, (uint8_t *) passwd + n,
3177                                              AUTH_PASS_LEN);
3178                         }
3179                 }
3180
3181                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3182                         passwd[i + n] ^= digest[i];
3183                 }
3184         }
3185
3186  done:
3187         passwd[pwlen] = '\0';
3188         return strlen(passwd);
3189 }
3190
3191
3192 /*
3193  *      Encode Tunnel-Password attributes when sending them out on the wire.
3194  *
3195  *      int *pwlen is updated to the new length of the encrypted
3196  *      password - a multiple of 16 bytes.
3197  *
3198  *      This is per RFC-2868 which adds a two char SALT to the initial intermediate
3199  *      value MD5 hash.
3200  */
3201 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, const char *secret,
3202                         const uint8_t *vector)
3203 {
3204         uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
3205         unsigned char   digest[AUTH_VECTOR_LEN];
3206         char*   salt;
3207         int     i, n, secretlen;
3208         unsigned len, n2;
3209
3210         len = *pwlen;
3211
3212         if (len > 127) len = 127;
3213
3214         /*
3215          * Shift the password 3 positions right to place a salt and original
3216          * length, tag will be added automatically on packet send
3217          */
3218         for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
3219         salt = passwd;
3220         passwd += 2;
3221         /*
3222          * save original password length as first password character;
3223          */
3224         *passwd = len;
3225         len += 1;
3226
3227
3228         /*
3229          *      Generate salt.  The RFC's say:
3230          *
3231          *      The high bit of salt[0] must be set, each salt in a
3232          *      packet should be unique, and they should be random
3233          *
3234          *      So, we set the high bit, add in a counter, and then
3235          *      add in some CSPRNG data.  should be OK..
3236          */
3237         salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
3238                    (fr_rand() & 0x07));
3239         salt[1] = fr_rand();
3240
3241         /*
3242          *      Padd password to multiple of AUTH_PASS_LEN bytes.
3243          */
3244         n = len % AUTH_PASS_LEN;
3245         if (n) {
3246                 n = AUTH_PASS_LEN - n;
3247                 for (; n > 0; n--, len++)
3248                         passwd[len] = 0;
3249         }
3250         /* set new password length */
3251         *pwlen = len + 2;
3252
3253         /*
3254          *      Use the secret to setup the decryption digest
3255          */
3256         secretlen = strlen(secret);
3257         memcpy(buffer, secret, secretlen);
3258
3259         for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
3260                 if (!n2) {
3261                         memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
3262                         memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
3263                         fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
3264                 } else {
3265                         memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
3266                         fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
3267                 }
3268
3269                 for (i = 0; i < AUTH_PASS_LEN; i++) {
3270                         passwd[i + n2] ^= digest[i];
3271                 }
3272         }
3273         passwd[n2] = 0;
3274         return 0;
3275 }
3276
3277 /*
3278  *      Decode Tunnel-Password encrypted attributes.
3279  *
3280  *      Defined in RFC-2868, this uses a two char SALT along with the
3281  *      initial intermediate value, to differentiate it from the
3282  *      above.
3283  */
3284 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, const char *secret,
3285                         const uint8_t *vector)
3286 {
3287         FR_MD5_CTX  context, old;
3288         uint8_t         digest[AUTH_VECTOR_LEN];
3289         int             secretlen;
3290         unsigned        i, n, len, reallen;
3291
3292         len = *pwlen;
3293
3294         /*
3295          *      We need at least a salt.
3296          */
3297         if (len < 2) {
3298                 fr_strerror_printf("tunnel password is too short");
3299                 return -1;
3300         }
3301
3302         /*
3303          *      There's a salt, but no password.  Or, there's a salt
3304          *      and a 'data_len' octet.  It's wrong, but at least we
3305          *      can figure out what it means: the password is empty.
3306          *
3307          *      Note that this means we ignore the 'data_len' field,
3308          *      if the attribute length tells us that there's no
3309          *      more data.  So the 'data_len' field may be wrong,
3310          *      but that's ok...
3311          */
3312         if (len <= 3) {
3313                 passwd[0] = 0;
3314                 *pwlen = 0;
3315                 return 0;
3316         }
3317
3318         len -= 2;               /* discount the salt */
3319
3320         /*
3321          *      Use the secret to setup the decryption digest
3322          */
3323         secretlen = strlen(secret);
3324
3325         fr_MD5Init(&context);
3326         fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3327         old = context;          /* save intermediate work */
3328
3329         /*
3330          *      Set up the initial key:
3331          *
3332          *       b(1) = MD5(secret + vector + salt)
3333          */
3334         fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3335         fr_MD5Update(&context, passwd, 2);
3336
3337         reallen = 0;
3338         for (n = 0; n < len; n += AUTH_PASS_LEN) {
3339                 int base = 0;
3340
3341                 if (n == 0) {
3342                         fr_MD5Final(digest, &context);
3343
3344                         context = old;
3345
3346                         /*
3347                          *      A quick check: decrypt the first octet
3348                          *      of the password, which is the
3349                          *      'data_len' field.  Ensure it's sane.
3350                          */
3351                         reallen = passwd[2] ^ digest[0];
3352                         if (reallen >= len) {
3353                                 fr_strerror_printf("tunnel password is too long for the attribute");
3354                                 return -1;
3355                         }
3356
3357                         fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
3358
3359                         base = 1;
3360                 } else {
3361                         fr_MD5Final(digest, &context);
3362
3363                         context = old;
3364                         fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
3365                 }
3366
3367                 for (i = base; i < AUTH_PASS_LEN; i++) {
3368                         passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
3369                 }
3370         }
3371
3372         /*
3373          *      See make_tunnel_password, above.
3374          */
3375         if (reallen > 239) reallen = 239;
3376
3377         *pwlen = reallen;
3378         passwd[reallen] = 0;
3379
3380         return reallen;
3381 }
3382
3383 /*
3384  *      Encode a CHAP password
3385  *
3386  *      FIXME: might not work with Ascend because
3387  *      we use vp->length, and Ascend gear likes
3388  *      to send an extra '\0' in the string!
3389  */
3390 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
3391                     VALUE_PAIR *password)
3392 {
3393         int             i;
3394         uint8_t         *ptr;
3395         uint8_t         string[MAX_STRING_LEN * 2 + 1];
3396         VALUE_PAIR      *challenge;
3397
3398         /*
3399          *      Sanity check the input parameters
3400          */
3401         if ((packet == NULL) || (password == NULL)) {
3402                 return -1;
3403         }
3404
3405         /*
3406          *      Note that the password VP can be EITHER
3407          *      a User-Password attribute (from a check-item list),
3408          *      or a CHAP-Password attribute (the client asking
3409          *      the library to encode it).
3410          */
3411
3412         i = 0;
3413         ptr = string;
3414         *ptr++ = id;
3415
3416         i++;
3417         memcpy(ptr, password->vp_strvalue, password->length);
3418         ptr += password->length;
3419         i += password->length;
3420
3421         /*
3422          *      Use Chap-Challenge pair if present,
3423          *      Request-Authenticator otherwise.
3424          */
3425         challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0);
3426         if (challenge) {
3427                 memcpy(ptr, challenge->vp_strvalue, challenge->length);
3428                 i += challenge->length;
3429         } else {
3430                 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
3431                 i += AUTH_VECTOR_LEN;
3432         }
3433
3434         *output = id;
3435         fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
3436
3437         return 0;
3438 }
3439
3440
3441 /*
3442  *      Seed the random number generator.
3443  *
3444  *      May be called any number of times.
3445  */
3446 void fr_rand_seed(const void *data, size_t size)
3447 {
3448         uint32_t hash;
3449
3450         /*
3451          *      Ensure that the pool is initialized.
3452          */
3453         if (!fr_rand_initialized) {
3454                 int fd;
3455
3456                 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
3457
3458                 fd = open("/dev/urandom", O_RDONLY);
3459                 if (fd >= 0) {
3460                         size_t total;
3461                         ssize_t this;
3462
3463                         total = this = 0;
3464                         while (total < sizeof(fr_rand_pool.randrsl)) {
3465                                 this = read(fd, fr_rand_pool.randrsl,
3466                                             sizeof(fr_rand_pool.randrsl) - total);
3467                                 if ((this < 0) && (errno != EINTR)) break;
3468                                 if (this > 0) total += this;
3469                         }
3470                         close(fd);
3471                 } else {
3472                         fr_rand_pool.randrsl[0] = fd;
3473                         fr_rand_pool.randrsl[1] = time(NULL);
3474                         fr_rand_pool.randrsl[2] = errno;
3475                 }
3476
3477                 fr_randinit(&fr_rand_pool, 1);
3478                 fr_rand_pool.randcnt = 0;
3479                 fr_rand_initialized = 1;
3480         }
3481
3482         if (!data) return;
3483
3484         /*
3485          *      Hash the user data
3486          */
3487         hash = fr_rand();
3488         if (!hash) hash = fr_rand();
3489         hash = fr_hash_update(data, size, hash);
3490
3491         fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
3492 }
3493
3494
3495 /*
3496  *      Return a 32-bit random number.
3497  */
3498 uint32_t fr_rand(void)
3499 {
3500         uint32_t num;
3501
3502         /*
3503          *      Ensure that the pool is initialized.
3504          */
3505         if (!fr_rand_initialized) {
3506                 fr_rand_seed(NULL, 0);
3507         }
3508
3509         num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
3510         if (fr_rand_pool.randcnt >= 256) {
3511                 fr_rand_pool.randcnt = 0;
3512                 fr_isaac(&fr_rand_pool);
3513         }
3514
3515         return num;
3516 }
3517
3518
3519 /*
3520  *      Allocate a new RADIUS_PACKET
3521  */
3522 RADIUS_PACKET *rad_alloc(int newvector)
3523 {
3524         RADIUS_PACKET   *rp;
3525
3526         if ((rp = malloc(sizeof(RADIUS_PACKET))) == NULL) {
3527                 fr_strerror_printf("out of memory");
3528                 return NULL;
3529         }
3530         memset(rp, 0, sizeof(*rp));
3531         rp->id = -1;
3532         rp->offset = -1;
3533
3534         if (newvector) {
3535                 int i;
3536                 uint32_t hash, base;
3537
3538                 /*
3539                  *      Don't expose the actual contents of the random
3540                  *      pool.
3541                  */
3542                 base = fr_rand();
3543                 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
3544                         hash = fr_rand() ^ base;
3545                         memcpy(rp->vector + i, &hash, sizeof(hash));
3546                 }
3547         }
3548         fr_rand();              /* stir the pool again */
3549
3550         return rp;
3551 }
3552
3553 RADIUS_PACKET *rad_alloc_reply(RADIUS_PACKET *packet)
3554 {
3555         RADIUS_PACKET *reply;
3556
3557         if (!packet) return NULL;
3558
3559         reply = rad_alloc(0);
3560         if (!reply) return NULL;
3561
3562         /*
3563          *      Initialize the fields from the request.
3564          */
3565         reply->sockfd = packet->sockfd;
3566         reply->dst_ipaddr = packet->src_ipaddr;
3567         reply->src_ipaddr = packet->dst_ipaddr;
3568         reply->dst_port = packet->src_port;
3569         reply->src_port = packet->dst_port;
3570         reply->id = packet->id;
3571         reply->code = 0; /* UNKNOWN code */
3572         memcpy(reply->vector, packet->vector,
3573                sizeof(reply->vector));
3574         reply->vps = NULL;
3575         reply->data = NULL;
3576         reply->data_len = 0;
3577
3578         return reply;
3579 }
3580
3581
3582 /*
3583  *      Free a RADIUS_PACKET
3584  */
3585 void rad_free(RADIUS_PACKET **radius_packet_ptr)
3586 {
3587         RADIUS_PACKET *radius_packet;
3588
3589         if (!radius_packet_ptr || !*radius_packet_ptr) return;
3590         radius_packet = *radius_packet_ptr;
3591
3592         free(radius_packet->data);
3593
3594         pairfree(&radius_packet->vps);
3595
3596         free(radius_packet);
3597
3598         *radius_packet_ptr = NULL;
3599 }