2 * This library is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU Lesser General Public
4 * License as published by the Free Software Foundation; either
5 * version 2.1 of the License, or (at your option) any later version.
7 * This library is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * Lesser General Public License for more details.
12 * You should have received a copy of the GNU Lesser General Public
13 * License along with this library; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
21 * @brief Functions to send/receive radius packets.
23 * @copyright 2000-2003,2006 The FreeRADIUS server project
28 #include <freeradius-devel/libradius.h>
30 #include <freeradius-devel/md5.h>
36 #include <freeradius-devel/udpfromto.h>
40 #define VP_TRACE if (fr_debug_flag) printf
42 static void VP_HEXDUMP(char const *msg, uint8_t const *data, size_t len)
46 printf("--- %s ---\n", msg);
47 for (i = 0; i < len; i++) {
48 if ((i & 0x0f) == 0) printf("%04x: ", (unsigned int) i);
49 printf("%02x ", data[i]);
50 if ((i & 0x0f) == 0x0f) printf("\n");
52 if ((len == 0x0f) || ((len & 0x0f) != 0x0f)) printf("\n");
56 #define VP_TRACE(_x, ...)
57 #define VP_HEXDUMP(_x, _y, _z)
62 * The RFC says 4096 octets max, and most packets are less than 256.
64 #define MAX_PACKET_LEN 4096
67 * The maximum number of attributes which we allow in an incoming
68 * request. If there are more attributes than this, the request
71 * This helps to minimize the potential for a DoS, when an
72 * attacker spoofs Access-Request packets, which don't have a
73 * Message-Authenticator attribute. This means that the packet
74 * is unsigned, and the attacker can use resources on the server,
75 * even if the end request is rejected.
77 int fr_max_attributes = 0;
78 FILE *fr_log_fp = NULL;
80 typedef struct radius_packet_t {
84 uint8_t vector[AUTH_VECTOR_LEN];
88 static fr_randctx fr_rand_pool; /* across multiple calls */
89 static int fr_rand_initialized = 0;
90 static unsigned int salt_offset = 0;
91 static uint8_t nullvector[AUTH_VECTOR_LEN] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* for CoA decode */
93 char const *fr_packet_codes[FR_MAX_PACKET_CODE] = {
99 "Accounting-Response",
104 "Accounting-Message",
115 "Resource-Free-Request",
116 "Resource-Free-Response",
117 "Resource-Query-Request",
118 "Resource-Query-Response",
119 "Alternate-Resource-Reclaim-Request",
120 "NAS-Reboot-Request",
121 "NAS-Reboot-Response",
134 "Disconnect-Request",
144 "IP-Address-Allocate",
149 void fr_printf_log(char const *fmt, ...)
154 if ((fr_debug_flag == 0) || !fr_log_fp) {
159 vfprintf(fr_log_fp, fmt, ap);
165 static char const *tabs = "\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t";
167 static void print_hex_data(uint8_t const *ptr, int attrlen, int depth)
171 for (i = 0; i < attrlen; i++) {
172 if ((i > 0) && ((i & 0x0f) == 0x00))
173 fprintf(fr_log_fp, "%.*s", depth, tabs);
174 fprintf(fr_log_fp, "%02x ", ptr[i]);
175 if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
177 if ((i & 0x0f) != 0) fprintf(fr_log_fp, "\n");
181 void rad_print_hex(RADIUS_PACKET *packet)
185 if (!packet->data || !fr_log_fp) return;
187 fprintf(fr_log_fp, " Code:\t\t%u\n", packet->data[0]);
188 fprintf(fr_log_fp, " Id:\t\t%u\n", packet->data[1]);
189 fprintf(fr_log_fp, " Length:\t%u\n", ((packet->data[2] << 8) |
191 fprintf(fr_log_fp, " Vector:\t");
192 for (i = 4; i < 20; i++) {
193 fprintf(fr_log_fp, "%02x", packet->data[i]);
195 fprintf(fr_log_fp, "\n");
197 if (packet->data_len > 20) {
200 fprintf(fr_log_fp, " Data:");
202 total = packet->data_len - 20;
203 ptr = packet->data + 20;
207 unsigned int vendor = 0;
209 fprintf(fr_log_fp, "\t\t");
210 if (total < 2) { /* too short */
211 fprintf(fr_log_fp, "%02x\n", *ptr);
215 if (ptr[1] > total) { /* too long */
216 for (i = 0; i < total; i++) {
217 fprintf(fr_log_fp, "%02x ", ptr[i]);
222 fprintf(fr_log_fp, "%02x %02x ", ptr[0], ptr[1]);
223 attrlen = ptr[1] - 2;
225 if ((ptr[0] == PW_VENDOR_SPECIFIC) &&
227 vendor = (ptr[3] << 16) | (ptr[4] << 8) | ptr[5];
228 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) ",
229 ptr[2], ptr[3], ptr[4], ptr[5], vendor);
239 print_hex_data(ptr, attrlen, 3);
249 * @brief Wrapper for sendto which handles sendfromto, IPv6, and all
250 * possible combinations.
252 static int rad_sendto(int sockfd, void *data, size_t data_len, int flags,
253 #ifdef WITH_UDPFROMTO
254 fr_ipaddr_t *src_ipaddr, int src_port,
256 UNUSED fr_ipaddr_t *src_ipaddr, UNUSED int src_port,
258 fr_ipaddr_t *dst_ipaddr, int dst_port)
261 struct sockaddr_storage dst;
262 socklen_t sizeof_dst;
264 #ifdef WITH_UDPFROMTO
265 struct sockaddr_storage src;
266 socklen_t sizeof_src;
268 fr_ipaddr2sockaddr(src_ipaddr, src_port, &src, &sizeof_src);
271 if (!fr_ipaddr2sockaddr(dst_ipaddr, dst_port, &dst, &sizeof_dst)) {
275 #ifdef WITH_UDPFROMTO
277 * And if they don't specify a source IP address, don't
280 if (((dst_ipaddr->af == AF_INET) || (dst_ipaddr->af == AF_INET6)) &&
281 (src_ipaddr->af != AF_UNSPEC) &&
282 !fr_inaddr_any(src_ipaddr)) {
283 rcode = sendfromto(sockfd, data, data_len, flags,
284 (struct sockaddr *)&src, sizeof_src,
285 (struct sockaddr *)&dst, sizeof_dst);
291 * No udpfromto, fail gracefully.
293 rcode = sendto(sockfd, data, data_len, flags,
294 (struct sockaddr *) &dst, sizeof_dst);
295 #ifdef WITH_UDPFROMTO
299 DEBUG("rad_send() failed: %s\n", strerror(errno));
306 void rad_recv_discard(int sockfd)
309 struct sockaddr_storage src;
310 socklen_t sizeof_src = sizeof(src);
312 (void) recvfrom(sockfd, header, sizeof(header), 0,
313 (struct sockaddr *)&src, &sizeof_src);
317 ssize_t rad_recv_header(int sockfd, fr_ipaddr_t *src_ipaddr, int *src_port,
320 ssize_t data_len, packet_len;
322 struct sockaddr_storage src;
323 socklen_t sizeof_src = sizeof(src);
325 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
326 (struct sockaddr *)&src, &sizeof_src);
328 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
333 * Too little data is available, discard the packet.
336 rad_recv_discard(sockfd);
340 } else { /* we got 4 bytes of data. */
342 * See how long the packet says it is.
344 packet_len = (header[2] * 256) + header[3];
347 * The length in the packet says it's less than
348 * a RADIUS header length: discard it.
350 if (packet_len < AUTH_HDR_LEN) {
351 rad_recv_discard(sockfd);
356 * Enforce RFC requirements, for sanity.
357 * Anything after 4k will be discarded.
359 } else if (packet_len > MAX_PACKET_LEN) {
360 rad_recv_discard(sockfd);
367 * Convert AF. If unknown, discard packet.
369 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, src_port)) {
370 rad_recv_discard(sockfd);
378 * The packet says it's this long, but the actual UDP
379 * size could still be smaller.
386 * @brief wrapper for recvfrom, which handles recvfromto, IPv6, and all
387 * possible combinations.
389 static ssize_t rad_recvfrom(int sockfd, RADIUS_PACKET *packet, int flags,
390 fr_ipaddr_t *src_ipaddr, uint16_t *src_port,
391 fr_ipaddr_t *dst_ipaddr, uint16_t *dst_port)
393 struct sockaddr_storage src;
394 struct sockaddr_storage dst;
395 socklen_t sizeof_src = sizeof(src);
396 socklen_t sizeof_dst = sizeof(dst);
402 memset(&src, 0, sizeof_src);
403 memset(&dst, 0, sizeof_dst);
406 * Get address family, etc. first, so we know if we
407 * need to do udpfromto.
409 * FIXME: udpfromto also does this, but it's not
410 * a critical problem.
412 if (getsockname(sockfd, (struct sockaddr *)&dst,
413 &sizeof_dst) < 0) return -1;
416 * Read the length of the packet, from the packet.
417 * This lets us allocate the buffer to use for
418 * reading the rest of the packet.
420 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
421 (struct sockaddr *)&src, &sizeof_src);
423 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
428 * Too little data is available, discard the packet.
431 rad_recv_discard(sockfd);
435 } else { /* we got 4 bytes of data. */
437 * See how long the packet says it is.
439 len = (header[2] * 256) + header[3];
442 * The length in the packet says it's less than
443 * a RADIUS header length: discard it.
445 if (len < AUTH_HDR_LEN) {
446 recvfrom(sockfd, header, sizeof(header), flags,
447 (struct sockaddr *)&src, &sizeof_src);
451 * Enforce RFC requirements, for sanity.
452 * Anything after 4k will be discarded.
454 } else if (len > MAX_PACKET_LEN) {
455 recvfrom(sockfd, header, sizeof(header), flags,
456 (struct sockaddr *)&src, &sizeof_src);
461 packet->data = talloc_array(packet, uint8_t, len);
462 if (!packet->data) return -1;
465 * Receive the packet. The OS will discard any data in the
466 * packet after "len" bytes.
468 #ifdef WITH_UDPFROMTO
469 if ((dst.ss_family == AF_INET) || (dst.ss_family == AF_INET6)) {
470 data_len = recvfromto(sockfd, packet->data, len, flags,
471 (struct sockaddr *)&src, &sizeof_src,
472 (struct sockaddr *)&dst, &sizeof_dst);
476 * No udpfromto, fail gracefully.
478 data_len = recvfrom(sockfd, packet->data, len, flags,
479 (struct sockaddr *)&src, &sizeof_src);
484 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, &port)) {
485 return -1; /* Unknown address family, Die Die Die! */
489 fr_sockaddr2ipaddr(&dst, sizeof_dst, dst_ipaddr, &port);
493 * Different address families should never happen.
495 if (src.ss_family != dst.ss_family) {
503 #define AUTH_PASS_LEN (AUTH_VECTOR_LEN)
505 * @brief Build an encrypted secret value to return in a reply packet
507 * The secret is hidden by xoring with a MD5 digest
508 * created from the shared secret and the authentication
509 * vector. We put them into MD5 in the reverse order from
510 * that used when encrypting passwords to RADIUS.
513 static void make_secret(uint8_t *digest, uint8_t const *vector,
514 char const *secret, uint8_t const *value)
519 fr_MD5Init(&context);
520 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
521 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
522 fr_MD5Final(digest, &context);
524 for ( i = 0; i < AUTH_VECTOR_LEN; i++ ) {
525 digest[i] ^= value[i];
529 #define MAX_PASS_LEN (128)
530 static void make_passwd(uint8_t *output, ssize_t *outlen,
531 uint8_t const *input, size_t inlen,
532 char const *secret, uint8_t const *vector)
534 FR_MD5_CTX context, old;
535 uint8_t digest[AUTH_VECTOR_LEN];
536 uint8_t passwd[MAX_PASS_LEN];
541 * If the length is zero, round it up.
545 if (len > MAX_PASS_LEN) len = MAX_PASS_LEN;
547 memcpy(passwd, input, len);
548 if (len < sizeof(passwd)) memset(passwd + len, 0, sizeof(passwd) - len);
554 else if ((len & 0x0f) != 0) {
560 fr_MD5Init(&context);
561 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
567 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
569 for (n = 0; n < len; n += AUTH_PASS_LEN) {
572 fr_MD5Update(&context,
573 passwd + n - AUTH_PASS_LEN,
577 fr_MD5Final(digest, &context);
578 for (i = 0; i < AUTH_PASS_LEN; i++) {
579 passwd[i + n] ^= digest[i];
583 memcpy(output, passwd, len);
586 static void make_tunnel_passwd(uint8_t *output, ssize_t *outlen,
587 uint8_t const *input, size_t inlen, size_t room,
588 char const *secret, uint8_t const *vector)
590 FR_MD5_CTX context, old;
591 uint8_t digest[AUTH_VECTOR_LEN];
592 uint8_t passwd[MAX_STRING_LEN + AUTH_VECTOR_LEN];
599 if (room > 253) room = 253;
602 * Account for 2 bytes of the salt, and round the room
603 * available down to the nearest multiple of 16. Then,
604 * subtract one from that to account for the length byte,
605 * and the resulting number is the upper bound on the data
608 * We could short-cut this calculation just be forcing
609 * inlen to be no more than 239. It would work for all
610 * VSA's, as we don't pack multiple VSA's into one
613 * However, this calculation is more general, if a little
614 * complex. And it will work in the future for all possible
615 * kinds of weird attribute packing.
618 room -= (room & 0x0f);
621 if (inlen > room) inlen = room;
624 * Length of the encrypted data is password length plus
625 * one byte for the length of the password.
628 if ((len & 0x0f) != 0) {
632 *outlen = len + 2; /* account for the salt */
635 * Copy the password over.
637 memcpy(passwd + 3, input, inlen);
638 memset(passwd + 3 + inlen, 0, sizeof(passwd) - 3 - inlen);
641 * Generate salt. The RFC's say:
643 * The high bit of salt[0] must be set, each salt in a
644 * packet should be unique, and they should be random
646 * So, we set the high bit, add in a counter, and then
647 * add in some CSPRNG data. should be OK..
649 passwd[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
651 passwd[1] = fr_rand();
652 passwd[2] = inlen; /* length of the password string */
654 fr_MD5Init(&context);
655 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
658 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
659 fr_MD5Update(&context, &passwd[0], 2);
661 for (n = 0; n < len; n += AUTH_PASS_LEN) {
664 fr_MD5Update(&context,
665 passwd + 2 + n - AUTH_PASS_LEN,
669 fr_MD5Final(digest, &context);
671 for (i = 0; i < AUTH_PASS_LEN; i++) {
672 passwd[i + 2 + n] ^= digest[i];
675 memcpy(output, passwd, len + 2);
678 extern int fr_attr_max_tlv;
679 extern int fr_attr_shift[];
680 extern int fr_attr_mask[];
682 static int do_next_tlv(VALUE_PAIR const *vp, VALUE_PAIR const *next, int nest)
684 unsigned int tlv1, tlv2;
686 if (nest > fr_attr_max_tlv) return 0;
691 * Keep encoding TLVs which have the same scope.
692 * e.g. two attributes of:
693 * ATTR.TLV1.TLV2.TLV3 = data1
694 * ATTR.TLV1.TLV2.TLV4 = data2
695 * both get put into a container of "ATTR.TLV1.TLV2"
699 * Nothing to follow, we're done.
704 * Not from the same vendor, skip it.
706 if (vp->da->vendor != next->da->vendor) return 0;
709 * In a different TLV space, skip it.
712 tlv2 = next->da->attr;
714 tlv1 &= ((1 << fr_attr_shift[nest]) - 1);
715 tlv2 &= ((1 << fr_attr_shift[nest]) - 1);
717 if (tlv1 != tlv2) return 0;
723 static ssize_t vp2data_any(RADIUS_PACKET const *packet,
724 RADIUS_PACKET const *original,
725 char const *secret, int nest,
726 VALUE_PAIR const **pvp,
727 uint8_t *start, size_t room);
729 static ssize_t vp2attr_rfc(RADIUS_PACKET const *packet,
730 RADIUS_PACKET const *original,
731 char const *secret, VALUE_PAIR const **pvp,
732 unsigned int attribute, uint8_t *ptr, size_t room);
735 * @brief This is really a sub-function of vp2data_any(). It encodes
736 * the *data* portion of the TLV, and assumes that the encapsulating
737 * attribute has already been encoded.
739 static ssize_t vp2data_tlvs(RADIUS_PACKET const *packet,
740 RADIUS_PACKET const *original,
741 char const *secret, int nest,
742 VALUE_PAIR const **pvp,
743 uint8_t *start, size_t room)
747 uint8_t *ptr = start;
748 const VALUE_PAIR *vp = *pvp;
749 const VALUE_PAIR *svp = vp;
754 if (nest > fr_attr_max_tlv) {
755 fr_strerror_printf("vp2data_tlvs: attribute nesting overflow");
761 if (room < 2) return ptr - start;
763 ptr[0] = (vp->da->attr >> fr_attr_shift[nest]) & fr_attr_mask[nest];
767 if (room > 255) my_room = 255;
769 len = vp2data_any(packet, original, secret, nest,
770 &vp, ptr + 2, my_room - 2);
771 if (len < 0) return len;
772 if (len == 0) return ptr - start;
773 /* len can NEVER be more than 253 */
778 if ((fr_debug_flag > 3) && fr_log_fp) {
779 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
780 print_hex_data(ptr + 2, len, 3);
788 if (!do_next_tlv(svp, vp, nest)) break;
792 if ((fr_debug_flag > 3) && fr_log_fp) {
795 da = dict_attrbyvalue(svp->da->attr & ((1 << fr_attr_shift[nest ]) - 1), svp->da->vendor);
796 if (da) fprintf(fr_log_fp, "\t%s = ...\n", da->name);
804 * @brief Encodes the data portion of an attribute.
805 * @return -1 on error, or the length of the data portion.
807 static ssize_t vp2data_any(RADIUS_PACKET const *packet,
808 RADIUS_PACKET const *original,
809 char const *secret, int nest,
810 VALUE_PAIR const **pvp,
811 uint8_t *start, size_t room)
816 uint8_t *ptr = start;
819 const VALUE_PAIR *vp = *pvp;
822 * See if we need to encode a TLV. The low portion of
823 * the attribute has already been placed into the packer.
824 * If there are still attribute bytes left, then go
825 * encode them as TLVs.
827 * If we cared about the stack, we could unroll the loop.
829 if (vp->da->flags.is_tlv && (nest < fr_attr_max_tlv) &&
830 ((vp->da->attr >> fr_attr_shift[nest + 1]) != 0)) {
831 return vp2data_tlvs(packet, original, secret, nest + 1, pvp,
838 * Set up the default sources for the data.
840 data = vp->vp_octets;
844 * Short-circuit it for long attributes. They can't be
845 * encrypted, tagged, etc.
847 if ((vp->da->type & PW_FLAG_LONG) != 0) goto do_tlv;
849 switch(vp->da->type) {
853 case PW_TYPE_IPV6ADDR:
854 case PW_TYPE_IPV6PREFIX:
855 case PW_TYPE_IPV4PREFIX:
856 case PW_TYPE_ABINARY:
857 /* nothing more to do */
861 len = 1; /* just in case */
862 array[0] = vp->vp_integer & 0xff;
867 len = 2; /* just in case */
868 array[0] = (vp->vp_integer >> 8) & 0xff;
869 array[1] = vp->vp_integer & 0xff;
873 case PW_TYPE_INTEGER:
874 len = 4; /* just in case */
875 lvalue = htonl(vp->vp_integer);
876 memcpy(array, &lvalue, sizeof(lvalue));
880 case PW_TYPE_INTEGER64:
881 len = 8; /* just in case */
882 lvalue64 = htonll(vp->vp_integer64);
883 data = (uint8_t *) &lvalue64;
887 data = (uint8_t const *) &vp->vp_ipaddr;
888 len = 4; /* just in case */
892 * There are no tagged date attributes.
895 lvalue = htonl(vp->vp_date);
896 data = (uint8_t const *) &lvalue;
897 len = 4; /* just in case */
904 len = 4; /* just in case */
905 slvalue = htonl(vp->vp_signed);
906 memcpy(array, &slvalue, sizeof(slvalue));
914 fr_strerror_printf("ERROR: Cannot encode NULL TLV");
919 default: /* unknown type: ignore it */
920 fr_strerror_printf("ERROR: Unknown attribute type %d",
934 * Bound the data to the calling size
936 if (len > (ssize_t) room) len = room;
939 * Encrypt the various password styles
941 * Attributes with encrypted values MUST be less than
944 switch (vp->da->flags.encrypt) {
945 case FLAG_ENCRYPT_USER_PASSWORD:
946 make_passwd(ptr, &len, data, len,
947 secret, packet->vector);
950 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
952 if (vp->da->flags.has_tag) lvalue = 1;
955 * Check if there's enough room. If there isn't,
956 * we discard the attribute.
958 * This is ONLY a problem if we have multiple VSA's
959 * in one Vendor-Specific, though.
961 if (room < (18 + lvalue)) return 0;
963 switch (packet->code) {
964 case PW_AUTHENTICATION_ACK:
965 case PW_AUTHENTICATION_REJECT:
966 case PW_ACCESS_CHALLENGE:
969 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->da->name);
973 if (lvalue) ptr[0] = vp->tag;
974 make_tunnel_passwd(ptr + lvalue, &len, data, len,
976 secret, original->vector);
978 case PW_ACCOUNTING_REQUEST:
979 case PW_DISCONNECT_REQUEST:
982 make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
983 secret, packet->vector);
989 * The code above ensures that this attribute
992 case FLAG_ENCRYPT_ASCEND_SECRET:
993 if (len != 16) return 0;
994 make_secret(ptr, packet->vector, secret, data);
995 len = AUTH_VECTOR_LEN;
1000 if (vp->da->flags.has_tag && TAG_VALID(vp->tag)) {
1001 if (vp->da->type == PW_TYPE_STRING) {
1002 if (len > ((ssize_t) (room - 1))) len = room - 1;
1005 } else if (vp->da->type == PW_TYPE_INTEGER) {
1007 } /* else it can't be any other type */
1009 memcpy(ptr, data, len);
1011 } /* switch over encryption flags */
1014 return len + (ptr - start);
1017 static ssize_t attr_shift(uint8_t const *start, uint8_t const *end,
1018 uint8_t *ptr, int hdr_len, ssize_t len,
1019 int flag_offset, int vsa_offset)
1021 int check_len = len - ptr[1];
1022 int total = len + hdr_len;
1025 * Pass 1: Check if the addition of the headers
1026 * overflows the available room. If so, return
1027 * what we were capable of encoding.
1030 while (check_len > (255 - hdr_len)) {
1032 check_len -= (255 - hdr_len);
1036 * Note that this results in a number of attributes maybe
1037 * being marked as "encoded", but which aren't in the
1038 * packet. Oh well. The solution is to fix the
1039 * "vp2data_any" function to take into account the header
1042 if ((ptr + ptr[1] + total) > end) {
1043 return (ptr + ptr[1]) - start;
1047 * Pass 2: Now that we know there's enough room,
1048 * re-arrange the data to form a set of valid
1049 * RADIUS attributes.
1052 int sublen = 255 - ptr[1];
1054 if (len <= sublen) {
1059 memmove(ptr + 255 + hdr_len, ptr + 255, sublen);
1060 memcpy(ptr + 255, ptr, hdr_len);
1062 if (vsa_offset) ptr[vsa_offset] += sublen;
1063 ptr[flag_offset] |= 0x80;
1067 if (vsa_offset) ptr[vsa_offset] = 3;
1071 if (vsa_offset) ptr[vsa_offset] += len;
1073 return (ptr + ptr[1]) - start;
1078 * @brief Encode an "extended" attribute.
1080 int rad_vp2extended(RADIUS_PACKET const *packet,
1081 RADIUS_PACKET const *original,
1082 char const *secret, VALUE_PAIR const **pvp,
1083 uint8_t *ptr, size_t room)
1087 uint8_t *start = ptr;
1088 const VALUE_PAIR *vp = *pvp;
1090 if (!vp->da->flags.extended) {
1091 fr_strerror_printf("rad_vp2extended called for non-extended attribute");
1096 * The attribute number is encoded into the upper 8 bits
1099 ptr[0] = (vp->da->vendor / FR_MAX_VENDOR) & 0xff;
1101 if (!vp->da->flags.long_extended) {
1102 if (room < 3) return 0;
1105 ptr[2] = vp->da->attr & fr_attr_mask[0];
1108 if (room < 4) return 0;
1111 ptr[2] = vp->da->attr & fr_attr_mask[0];
1116 * Only "flagged" attributes can be longer than one
1119 if (!vp->da->flags.long_extended && (room > 255)) {
1126 if (vp->da->flags.evs) {
1127 uint8_t *evs = ptr + ptr[1];
1129 if (room < (size_t) (ptr[1] + 5)) return 0;
1133 evs[0] = 0; /* always zero */
1134 evs[1] = (vp->da->vendor >> 16) & 0xff;
1135 evs[2] = (vp->da->vendor >> 8) & 0xff;
1136 evs[3] = vp->da->vendor & 0xff;
1137 evs[4] = vp->da->attr & fr_attr_mask[0];
1143 len = vp2data_any(packet, original, secret, 0,
1144 pvp, ptr + ptr[1], room - hdr_len);
1145 if (len <= 0) return len;
1148 * There may be more than 252 octets of data encoded in
1149 * the attribute. If so, move the data up in the packet,
1150 * and copy the existing header over. Set the "M" flag ONLY
1151 * after copying the rest of the data.
1153 if (vp->da->flags.long_extended && (len > (255 - ptr[1]))) {
1154 return attr_shift(start, start + room, ptr, 4, len, 3, 0);
1160 if ((fr_debug_flag > 3) && fr_log_fp) {
1163 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1164 if (!vp->da->flags.long_extended) {
1165 fprintf(fr_log_fp, "%02x ", ptr[2]);
1168 fprintf(fr_log_fp, "%02x %02x ", ptr[2], ptr[3]);
1172 if (vp->da->flags.evs) {
1173 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) %02x ",
1174 ptr[jump], ptr[jump + 1],
1175 ptr[jump + 2], ptr[jump + 3],
1176 ((ptr[jump + 1] << 16) |
1177 (ptr[jump + 2] << 8) |
1183 print_hex_data(ptr + jump, len, 3);
1187 return (ptr + ptr[1]) - start;
1192 * @brief Encode a WiMAX attribute.
1194 int rad_vp2wimax(RADIUS_PACKET const *packet,
1195 RADIUS_PACKET const *original,
1196 char const *secret, VALUE_PAIR const **pvp,
1197 uint8_t *ptr, size_t room)
1202 uint8_t *start = ptr;
1203 const VALUE_PAIR *vp = *pvp;
1206 * Double-check for WiMAX format.
1208 if (!vp->da->flags.wimax) {
1209 fr_strerror_printf("rad_vp2wimax called for non-WIMAX VSA");
1214 * Not enough room for:
1215 * attr, len, vendor-id, vsa, vsalen, continuation
1217 if (room < 9) return 0;
1220 * Build the Vendor-Specific header
1223 ptr[0] = PW_VENDOR_SPECIFIC;
1225 lvalue = htonl(vp->da->vendor);
1226 memcpy(ptr + 2, &lvalue, 4);
1227 ptr[6] = (vp->da->attr & fr_attr_mask[1]);
1229 ptr[8] = 0; /* continuation byte */
1233 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1],
1235 if (len <= 0) return len;
1238 * There may be more than 252 octets of data encoded in
1239 * the attribute. If so, move the data up in the packet,
1240 * and copy the existing header over. Set the "C" flag
1241 * ONLY after copying the rest of the data.
1243 if (len > (255 - ptr[1])) {
1244 return attr_shift(start, start + room, ptr, hdr_len, len, 8, 7);
1251 if ((fr_debug_flag > 3) && fr_log_fp) {
1252 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) %02x %02x %02x ",
1254 ptr[2], ptr[3], ptr[4], ptr[5],
1255 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5],
1256 ptr[6], ptr[7], ptr[8]);
1257 print_hex_data(ptr + 9, len, 3);
1261 return (ptr + ptr[1]) - start;
1265 * @brief Encode an RFC format TLV.
1267 * This could be a standard attribute,
1268 * or a TLV data type. If it's a standard attribute, then
1269 * vp->da->attr == attribute. Otherwise, attribute may be
1272 static ssize_t vp2attr_rfc(RADIUS_PACKET const *packet,
1273 RADIUS_PACKET const *original,
1274 char const *secret, VALUE_PAIR const **pvp,
1275 unsigned int attribute, uint8_t *ptr, size_t room)
1279 if (room < 2) return 0;
1281 ptr[0] = attribute & 0xff;
1284 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1286 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1], room);
1287 if (len <= 0) return len;
1292 if ((fr_debug_flag > 3) && fr_log_fp) {
1293 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1294 print_hex_data(ptr + 2, len, 3);
1303 * @brief Encode a VSA which is a TLV. If it's in the RFC format, call
1304 * vp2attr_rfc. Otherwise, encode it here.
1306 static ssize_t vp2attr_vsa(RADIUS_PACKET const *packet,
1307 RADIUS_PACKET const *original,
1308 char const *secret, VALUE_PAIR const **pvp,
1309 unsigned int attribute, unsigned int vendor,
1310 uint8_t *ptr, size_t room)
1314 const VALUE_PAIR *vp = *pvp;
1317 * Unknown vendor: RFC format.
1318 * Known vendor and RFC format: go do that.
1320 dv = dict_vendorbyvalue(vendor);
1322 (!vp->da->flags.is_tlv && (dv->type == 1) && (dv->length == 1))) {
1323 return vp2attr_rfc(packet, original, secret, pvp,
1324 attribute, ptr, room);
1329 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1330 " type %u", (unsigned) dv->type);
1334 ptr[0] = 0; /* attr must be 24-bit */
1335 ptr[1] = (attribute >> 16) & 0xff;
1336 ptr[2] = (attribute >> 8) & 0xff;
1337 ptr[3] = attribute & 0xff;
1341 ptr[0] = (attribute >> 8) & 0xff;
1342 ptr[1] = attribute & 0xff;
1346 ptr[0] = attribute & 0xff;
1350 switch (dv->length) {
1352 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1353 " length %u", (unsigned) dv->length);
1361 ptr[dv->type + 1] = dv->type + 2;
1365 ptr[dv->type] = dv->type + 1;
1370 if (room > ((unsigned) 255 - (dv->type + dv->length))) {
1371 room = 255 - (dv->type + dv->length);
1374 len = vp2data_any(packet, original, secret, 0, pvp,
1375 ptr + dv->type + dv->length, room);
1376 if (len <= 0) return len;
1378 if (dv->length) ptr[dv->type + dv->length - 1] += len;
1381 if ((fr_debug_flag > 3) && fr_log_fp) {
1387 if ((fr_debug_flag > 3) && fr_log_fp)
1388 fprintf(fr_log_fp, "\t\t%02x%02x%02x%02x ",
1389 ptr[0], ptr[1], ptr[2], ptr[3]);
1393 if ((fr_debug_flag > 3) && fr_log_fp)
1394 fprintf(fr_log_fp, "\t\t%02x%02x ",
1399 if ((fr_debug_flag > 3) && fr_log_fp)
1400 fprintf(fr_log_fp, "\t\t%02x ", ptr[0]);
1404 switch (dv->length) {
1409 fprintf(fr_log_fp, " ");
1413 fprintf(fr_log_fp, "%02x ",
1418 fprintf(fr_log_fp, "%02x%02x ",
1419 ptr[dv->type], ptr[dv->type] + 1);
1423 print_hex_data(ptr + dv->type + dv->length, len, 3);
1427 return dv->type + dv->length + len;
1432 * @brief Encode a Vendor-Specific attribute.
1434 int rad_vp2vsa(RADIUS_PACKET const *packet, RADIUS_PACKET const *original,
1435 char const *secret, VALUE_PAIR const **pvp, uint8_t *ptr,
1440 const VALUE_PAIR *vp = *pvp;
1443 * Double-check for WiMAX format.
1445 if (vp->da->flags.wimax) {
1446 return rad_vp2wimax(packet, original, secret, pvp,
1450 if (vp->da->vendor > FR_MAX_VENDOR) {
1451 fr_strerror_printf("rad_vp2vsa: Invalid arguments");
1456 * Not enough room for:
1457 * attr, len, vendor-id
1459 if (room < 6) return 0;
1462 * Build the Vendor-Specific header
1464 ptr[0] = PW_VENDOR_SPECIFIC;
1466 lvalue = htonl(vp->da->vendor);
1467 memcpy(ptr + 2, &lvalue, 4);
1469 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1471 len = vp2attr_vsa(packet, original, secret, pvp,
1472 vp->da->attr, vp->da->vendor,
1473 ptr + ptr[1], room);
1474 if (len < 0) return len;
1477 if ((fr_debug_flag > 3) && fr_log_fp) {
1478 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) ",
1480 ptr[2], ptr[3], ptr[4], ptr[5],
1481 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5]);
1482 print_hex_data(ptr + 6, len, 3);
1493 * @brief Encode an RFC standard attribute 1..255
1495 int rad_vp2rfc(RADIUS_PACKET const *packet,
1496 RADIUS_PACKET const *original,
1497 char const *secret, VALUE_PAIR const **pvp,
1498 uint8_t *ptr, size_t room)
1500 const VALUE_PAIR *vp = *pvp;
1502 if (vp->da->vendor != 0) {
1503 fr_strerror_printf("rad_vp2rfc called with VSA");
1507 if ((vp->da->attr == 0) || (vp->da->attr > 255)) {
1508 fr_strerror_printf("rad_vp2rfc called with non-standard attribute %u", vp->da->attr);
1513 * Only CUI is allowed to have zero length.
1516 if ((vp->length == 0) &&
1517 (vp->da->attr == PW_CHARGEABLE_USER_IDENTITY)) {
1518 ptr[0] = PW_CHARGEABLE_USER_IDENTITY;
1526 * Message-Authenticator is hard-coded.
1528 if (vp->da->attr == PW_MESSAGE_AUTHENTICATOR) {
1529 if (room < 18) return -1;
1532 ptr[0] = PW_MESSAGE_AUTHENTICATOR;
1534 memset(ptr + 2, 0, 16);
1536 if ((fr_debug_flag > 3) && fr_log_fp) {
1537 fprintf(fr_log_fp, "\t\t50 12 ...\n");
1541 *pvp = (*pvp)->next;
1545 return vp2attr_rfc(packet, original, secret, pvp, vp->da->attr,
1549 static ssize_t rad_vp2rfctlv(RADIUS_PACKET const *packet,
1550 RADIUS_PACKET const *original,
1551 char const *secret, VALUE_PAIR const **pvp,
1552 uint8_t *start, size_t room)
1555 const VALUE_PAIR *vp = *pvp;
1557 if (!vp->da->flags.is_tlv) {
1558 fr_strerror_printf("rad_vp2rfctlv: attr is not a TLV");
1562 if ((vp->da->vendor & (FR_MAX_VENDOR - 1)) != 0) {
1563 fr_strerror_printf("rad_vp2rfctlv: attr is not an RFC TLV");
1567 if (room < 5) return 0;
1570 * Encode the first level of TLVs
1572 start[0] = (vp->da->vendor / FR_MAX_VENDOR) & 0xff;
1574 start[2] = vp->da->attr & fr_attr_mask[0];
1577 len = vp2data_any(packet, original, secret, 0, pvp,
1578 start + 4, room - 4);
1579 if (len <= 0) return len;
1592 * @brief Parse a data structure into a RADIUS attribute.
1594 int rad_vp2attr(RADIUS_PACKET const *packet, RADIUS_PACKET const *original,
1595 char const *secret, VALUE_PAIR const **pvp, uint8_t *start,
1598 const VALUE_PAIR *vp;
1600 if (!pvp || !*pvp || !start || (room <= 2)) return -1;
1605 * RFC format attributes take the fast path.
1607 if (!vp->da->vendor) {
1608 if (vp->da->attr > 255) return 0;
1610 return rad_vp2rfc(packet, original, secret, pvp,
1614 if (vp->da->flags.extended) {
1615 return rad_vp2extended(packet, original, secret, pvp,
1620 * The upper 8 bits of the vendor number are the standard
1621 * space attribute which is a TLV.
1623 if ((vp->da->vendor & (FR_MAX_VENDOR - 1)) == 0) {
1624 return rad_vp2rfctlv(packet, original, secret, pvp,
1628 if (vp->da->flags.wimax) {
1629 return rad_vp2wimax(packet, original, secret, pvp,
1633 return rad_vp2vsa(packet, original, secret, pvp,
1639 * @brief Encode a packet.
1641 int rad_encode(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
1644 radius_packet_t *hdr;
1646 uint16_t total_length;
1648 const VALUE_PAIR *reply;
1650 char ip_src_buffer[128];
1651 char ip_dst_buffer[128];
1654 * A 4K packet, aligned on 64-bits.
1656 uint64_t data[MAX_PACKET_LEN / sizeof(uint64_t)];
1658 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1659 what = fr_packet_codes[packet->code];
1664 DEBUG("Sending %s of id %d from %s port %u to %s port %u\n",
1666 inet_ntop(packet->src_ipaddr.af,
1667 &packet->src_ipaddr.ipaddr,
1668 ip_src_buffer, sizeof(ip_src_buffer)),
1670 inet_ntop(packet->dst_ipaddr.af,
1671 &packet->dst_ipaddr.ipaddr,
1672 ip_dst_buffer, sizeof(ip_dst_buffer)),
1676 * Double-check some things based on packet code.
1678 switch (packet->code) {
1679 case PW_AUTHENTICATION_ACK:
1680 case PW_AUTHENTICATION_REJECT:
1681 case PW_ACCESS_CHALLENGE:
1683 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1689 * These packet vectors start off as all zero.
1691 case PW_ACCOUNTING_REQUEST:
1692 case PW_DISCONNECT_REQUEST:
1693 case PW_COA_REQUEST:
1694 memset(packet->vector, 0, sizeof(packet->vector));
1702 * Use memory on the stack, until we know how
1703 * large the packet will be.
1705 hdr = (radius_packet_t *) data;
1708 * Build standard header
1710 hdr->code = packet->code;
1711 hdr->id = packet->id;
1713 memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1715 total_length = AUTH_HDR_LEN;
1718 * Load up the configuration values for the user
1724 * FIXME: Loop twice over the reply list. The first time,
1725 * calculate the total length of data. The second time,
1726 * allocate the memory, and fill in the VP's.
1728 * Hmm... this may be slower than just doing a small
1733 * Loop over the reply attributes for the packet.
1735 reply = packet->vps;
1738 char const *last_name = NULL;
1741 * Ignore non-wire attributes, but allow extended
1744 if ((reply->da->vendor == 0) &&
1745 ((reply->da->attr & 0xFFFF) >= 256) &&
1746 !reply->da->flags.extended && !reply->da->flags.long_extended) {
1749 * Permit the admin to send BADLY formatted
1750 * attributes with a debug build.
1752 if (reply->da->attr == PW_RAW_ATTRIBUTE) {
1753 memcpy(ptr, reply->vp_octets, reply->length);
1754 len = reply->length;
1755 reply = reply->next;
1759 reply = reply->next;
1764 * Set the Message-Authenticator to the correct
1765 * length and initial value.
1767 if (reply->da->attr == PW_MESSAGE_AUTHENTICATOR) {
1769 * Cache the offset to the
1770 * Message-Authenticator
1772 packet->offset = total_length;
1775 last_len = reply->length;
1777 last_name = reply->da->name;
1779 len = rad_vp2attr(packet, original, secret, &reply, ptr,
1780 ((uint8_t *) data) + sizeof(data) - ptr);
1781 if (len < 0) return -1;
1784 * Failed to encode the attribute, likely because
1785 * the packet is full.
1788 if (last_len != 0) {
1789 DEBUG("WARNING: Failed encoding attribute %s\n", last_name);
1791 DEBUG("WARNING: Skipping zero-length attribute %s\n", last_name);
1796 next: /* Used only for Raw-Attribute */
1799 total_length += len;
1800 } /* done looping over all attributes */
1803 * Fill in the rest of the fields, and copy the data over
1804 * from the local stack to the newly allocated memory.
1806 * Yes, all this 'memcpy' is slow, but it means
1807 * that we only allocate the minimum amount of
1808 * memory for a request.
1810 packet->data_len = total_length;
1811 packet->data = talloc_array(packet, uint8_t, packet->data_len);
1812 if (!packet->data) {
1813 fr_strerror_printf("Out of memory");
1817 memcpy(packet->data, hdr, packet->data_len);
1818 hdr = (radius_packet_t *) packet->data;
1820 total_length = htons(total_length);
1821 memcpy(hdr->length, &total_length, sizeof(total_length));
1828 * @brief Sign a previously encoded packet.
1830 int rad_sign(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
1833 radius_packet_t *hdr = (radius_packet_t *)packet->data;
1836 * It wasn't assigned an Id, this is bad!
1838 if (packet->id < 0) {
1839 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1843 if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1844 (packet->offset < 0)) {
1845 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1850 * If there's a Message-Authenticator, update it
1851 * now, BEFORE updating the authentication vector.
1853 if (packet->offset > 0) {
1854 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1856 switch (packet->code) {
1857 case PW_ACCOUNTING_RESPONSE:
1858 if (original && original->code == PW_STATUS_SERVER) {
1862 case PW_ACCOUNTING_REQUEST:
1863 case PW_DISCONNECT_REQUEST:
1864 case PW_DISCONNECT_ACK:
1865 case PW_DISCONNECT_NAK:
1866 case PW_COA_REQUEST:
1869 memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1873 case PW_AUTHENTICATION_ACK:
1874 case PW_AUTHENTICATION_REJECT:
1875 case PW_ACCESS_CHALLENGE:
1877 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1880 memcpy(hdr->vector, original->vector,
1884 default: /* others have vector already set to zero */
1890 * Set the authentication vector to zero,
1891 * calculate the HMAC, and put it
1892 * into the Message-Authenticator
1895 fr_hmac_md5(packet->data, packet->data_len,
1896 (uint8_t const *) secret, strlen(secret),
1898 memcpy(packet->data + packet->offset + 2,
1899 calc_auth_vector, AUTH_VECTOR_LEN);
1902 * Copy the original request vector back
1903 * to the raw packet.
1905 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1909 * Switch over the packet code, deciding how to
1912 switch (packet->code) {
1914 * Request packets are not signed, bur
1915 * have a random authentication vector.
1917 case PW_AUTHENTICATION_REQUEST:
1918 case PW_STATUS_SERVER:
1922 * Reply packets are signed with the
1923 * authentication vector of the request.
1930 fr_MD5Init(&context);
1931 fr_MD5Update(&context, packet->data, packet->data_len);
1932 fr_MD5Update(&context, (uint8_t const *) secret,
1934 fr_MD5Final(digest, &context);
1936 memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1937 memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1940 }/* switch over packet codes */
1946 * @brief Reply to the request. Also attach
1947 * reply attribute value pairs and any user message provided.
1949 int rad_send(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
1954 char ip_src_buffer[128];
1955 char ip_dst_buffer[128];
1958 * Maybe it's a fake packet. Don't send it.
1960 if (!packet || (packet->sockfd < 0)) {
1964 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1965 what = fr_packet_codes[packet->code];
1971 * First time through, allocate room for the packet
1973 if (!packet->data) {
1975 * Encode the packet.
1977 if (rad_encode(packet, original, secret) < 0) {
1982 * Re-sign it, including updating the
1983 * Message-Authenticator.
1985 if (rad_sign(packet, original, secret) < 0) {
1990 * If packet->data points to data, then we print out
1991 * the VP list again only for debugging.
1993 } else if (fr_debug_flag) {
1994 DEBUG("Sending %s of id %d from %s port %u to %s port %u\n", what,
1996 inet_ntop(packet->src_ipaddr.af,
1997 &packet->src_ipaddr.ipaddr,
1998 ip_src_buffer, sizeof(ip_src_buffer)),
2000 inet_ntop(packet->dst_ipaddr.af,
2001 &packet->dst_ipaddr.ipaddr,
2002 ip_dst_buffer, sizeof(ip_dst_buffer)),
2005 for (reply = packet->vps; reply; reply = reply->next) {
2006 if ((reply->da->vendor == 0) &&
2007 ((reply->da->attr & 0xFFFF) > 0xff)) continue;
2013 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2017 * And send it on it's way.
2019 return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
2020 &packet->src_ipaddr, packet->src_port,
2021 &packet->dst_ipaddr, packet->dst_port);
2025 * @brief Do a comparison of two authentication digests by comparing
2028 * Otherwise, the server can be subject to
2029 * timing attacks that allow attackers find a valid message
2032 * http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
2034 int rad_digest_cmp(uint8_t const *a, uint8_t const *b, size_t length)
2039 for (i = 0; i < length; i++) {
2040 result |= a[i] ^ b[i];
2043 return result; /* 0 is OK, !0 is !OK, just like memcmp */
2048 * @brief Validates the requesting client NAS. Calculates the
2049 * Request Authenticator based on the clients private key.
2051 static int calc_acctdigest(RADIUS_PACKET *packet, char const *secret)
2053 uint8_t digest[AUTH_VECTOR_LEN];
2057 * Zero out the auth_vector in the received packet.
2058 * Then append the shared secret to the received packet,
2059 * and calculate the MD5 sum. This must be the same
2060 * as the original MD5 sum (packet->vector).
2062 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2065 * MD5(packet + secret);
2067 fr_MD5Init(&context);
2068 fr_MD5Update(&context, packet->data, packet->data_len);
2069 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
2070 fr_MD5Final(digest, &context);
2073 * Return 0 if OK, 2 if not OK.
2075 if (rad_digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
2081 * @brief Validates the requesting client NAS. Calculates the
2082 * Response Authenticator based on the clients private key.
2084 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2087 uint8_t calc_digest[AUTH_VECTOR_LEN];
2093 if (original == NULL) {
2098 * Copy the original vector in place.
2100 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2103 * MD5(packet + secret);
2105 fr_MD5Init(&context);
2106 fr_MD5Update(&context, packet->data, packet->data_len);
2107 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
2108 fr_MD5Final(calc_digest, &context);
2111 * Copy the packet's vector back to the packet.
2113 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2116 * Return 0 if OK, 2 if not OK.
2118 if (rad_digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
2124 * @brief Check if a set of RADIUS formatted TLVs are OK.
2126 int rad_tlv_ok(uint8_t const *data, size_t length,
2127 size_t dv_type, size_t dv_length)
2129 const uint8_t *end = data + length;
2131 if ((dv_length > 2) || (dv_type == 0) || (dv_type > 4)) {
2132 fr_strerror_printf("rad_tlv_ok: Invalid arguments");
2136 while (data < end) {
2139 if ((data + dv_type + dv_length) > end) {
2140 fr_strerror_printf("Attribute header overflow");
2146 if ((data[0] == 0) && (data[1] == 0) &&
2147 (data[2] == 0) && (data[3] == 0)) {
2149 fr_strerror_printf("Invalid attribute 0");
2154 fr_strerror_printf("Invalid attribute > 2^24");
2160 if ((data[0] == 0) && (data[1] == 0)) goto zero;
2164 if (data[0] == 0) goto zero;
2168 fr_strerror_printf("Internal sanity check failed");
2172 switch (dv_length) {
2177 if (data[dv_type + 1] != 0) {
2178 fr_strerror_printf("Attribute is longer than 256 octets");
2183 attrlen = data[dv_type + dv_length - 1];
2188 fr_strerror_printf("Internal sanity check failed");
2192 if (attrlen < (dv_type + dv_length)) {
2193 fr_strerror_printf("Attribute header has invalid length");
2197 if (attrlen > length) {
2198 fr_strerror_printf("Attribute overflows container");
2211 * @brief See if the data pointed to by PTR is a valid RADIUS packet.
2213 * packet is not 'const * const' because we may update data_len,
2214 * if there's more data in the UDP packet than in the RADIUS packet.
2216 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
2221 radius_packet_t *hdr;
2222 char host_ipaddr[128];
2228 * Check for packets smaller than the packet header.
2230 * RFC 2865, Section 3., subsection 'length' says:
2232 * "The minimum length is 20 ..."
2234 if (packet->data_len < AUTH_HDR_LEN) {
2235 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %zu < minimum %d)",
2236 inet_ntop(packet->src_ipaddr.af,
2237 &packet->src_ipaddr.ipaddr,
2238 host_ipaddr, sizeof(host_ipaddr)),
2239 packet->data_len, AUTH_HDR_LEN);
2245 * Check for packets with mismatched size.
2246 * i.e. We've received 128 bytes, and the packet header
2247 * says it's 256 bytes long.
2249 totallen = (packet->data[2] << 8) | packet->data[3];
2250 hdr = (radius_packet_t *)packet->data;
2253 * Code of 0 is not understood.
2254 * Code of 16 or greate is not understood.
2256 if ((hdr->code == 0) ||
2257 (hdr->code >= FR_MAX_PACKET_CODE)) {
2258 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code %d",
2259 inet_ntop(packet->src_ipaddr.af,
2260 &packet->src_ipaddr.ipaddr,
2261 host_ipaddr, sizeof(host_ipaddr)),
2267 * Message-Authenticator is required in Status-Server
2268 * packets, otherwise they can be trivially forged.
2270 if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
2273 * It's also required if the caller asks for it.
2275 if (flags) require_ma = 1;
2278 * Repeat the length checks. This time, instead of
2279 * looking at the data we received, look at the value
2280 * of the 'length' field inside of the packet.
2282 * Check for packets smaller than the packet header.
2284 * RFC 2865, Section 3., subsection 'length' says:
2286 * "The minimum length is 20 ..."
2288 if (totallen < AUTH_HDR_LEN) {
2289 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %zu < minimum %d)",
2290 inet_ntop(packet->src_ipaddr.af,
2291 &packet->src_ipaddr.ipaddr,
2292 host_ipaddr, sizeof(host_ipaddr)),
2293 totallen, AUTH_HDR_LEN);
2298 * And again, for the value of the 'length' field.
2300 * RFC 2865, Section 3., subsection 'length' says:
2302 * " ... and maximum length is 4096."
2304 * HOWEVER. This requirement is for the network layer.
2305 * If the code gets here, we assume that a well-formed
2306 * packet is an OK packet.
2308 * We allow both the UDP data length, and the RADIUS
2309 * "length" field to contain up to 64K of data.
2313 * RFC 2865, Section 3., subsection 'length' says:
2315 * "If the packet is shorter than the Length field
2316 * indicates, it MUST be silently discarded."
2318 * i.e. No response to the NAS.
2320 if (packet->data_len < totallen) {
2321 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %zu octets, packet length says %zu",
2322 inet_ntop(packet->src_ipaddr.af,
2323 &packet->src_ipaddr.ipaddr,
2324 host_ipaddr, sizeof(host_ipaddr)),
2325 packet->data_len, totallen);
2330 * RFC 2865, Section 3., subsection 'length' says:
2332 * "Octets outside the range of the Length field MUST be
2333 * treated as padding and ignored on reception."
2335 if (packet->data_len > totallen) {
2337 * We're shortening the packet below, but just
2338 * to be paranoid, zero out the extra data.
2340 memset(packet->data + totallen, 0, packet->data_len - totallen);
2341 packet->data_len = totallen;
2345 * Walk through the packet's attributes, ensuring that
2346 * they add up EXACTLY to the size of the packet.
2348 * If they don't, then the attributes either under-fill
2349 * or over-fill the packet. Any parsing of the packet
2350 * is impossible, and will result in unknown side effects.
2352 * This would ONLY happen with buggy RADIUS implementations,
2353 * or with an intentional attack. Either way, we do NOT want
2354 * to be vulnerable to this problem.
2357 count = totallen - AUTH_HDR_LEN;
2362 * We need at least 2 bytes to check the
2366 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute header overflows the packet",
2367 inet_ntop(packet->src_ipaddr.af,
2368 &packet->src_ipaddr.ipaddr,
2369 host_ipaddr, sizeof(host_ipaddr)));
2374 * Attribute number zero is NOT defined.
2377 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
2378 inet_ntop(packet->src_ipaddr.af,
2379 &packet->src_ipaddr.ipaddr,
2380 host_ipaddr, sizeof(host_ipaddr)));
2385 * Attributes are at LEAST as long as the ID & length
2386 * fields. Anything shorter is an invalid attribute.
2389 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u too short",
2390 inet_ntop(packet->src_ipaddr.af,
2391 &packet->src_ipaddr.ipaddr,
2392 host_ipaddr, sizeof(host_ipaddr)),
2398 * If there are fewer bytes in the packet than in the
2399 * attribute, it's a bad packet.
2401 if (count < attr[1]) {
2402 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u data overflows the packet",
2403 inet_ntop(packet->src_ipaddr.af,
2404 &packet->src_ipaddr.ipaddr,
2405 host_ipaddr, sizeof(host_ipaddr)),
2411 * Sanity check the attributes for length.
2414 default: /* don't do anything by default */
2418 * If there's an EAP-Message, we require
2419 * a Message-Authenticator.
2421 case PW_EAP_MESSAGE:
2425 case PW_MESSAGE_AUTHENTICATOR:
2426 if (attr[1] != 2 + AUTH_VECTOR_LEN) {
2427 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
2428 inet_ntop(packet->src_ipaddr.af,
2429 &packet->src_ipaddr.ipaddr,
2430 host_ipaddr, sizeof(host_ipaddr)),
2439 * FIXME: Look up the base 255 attributes in the
2440 * dictionary, and switch over their type. For
2441 * integer/date/ip, the attribute length SHOULD
2444 count -= attr[1]; /* grab the attribute length */
2446 num_attributes++; /* seen one more attribute */
2450 * If the attributes add up to a packet, it's allowed.
2452 * If not, we complain, and throw the packet away.
2455 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
2456 inet_ntop(packet->src_ipaddr.af,
2457 &packet->src_ipaddr.ipaddr,
2458 host_ipaddr, sizeof(host_ipaddr)));
2463 * If we're configured to look for a maximum number of
2464 * attributes, and we've seen more than that maximum,
2465 * then throw the packet away, as a possible DoS.
2467 if ((fr_max_attributes > 0) &&
2468 (num_attributes > fr_max_attributes)) {
2469 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2470 inet_ntop(packet->src_ipaddr.af,
2471 &packet->src_ipaddr.ipaddr,
2472 host_ipaddr, sizeof(host_ipaddr)),
2473 num_attributes, fr_max_attributes);
2478 * http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
2480 * A packet with an EAP-Message attribute MUST also have
2481 * a Message-Authenticator attribute.
2483 * A Message-Authenticator all by itself is OK, though.
2485 * Similarly, Status-Server packets MUST contain
2486 * Message-Authenticator attributes.
2488 if (require_ma && ! seen_ma) {
2489 fr_strerror_printf("WARNING: Insecure packet from host %s: Packet does not contain required Message-Authenticator attribute",
2490 inet_ntop(packet->src_ipaddr.af,
2491 &packet->src_ipaddr.ipaddr,
2492 host_ipaddr, sizeof(host_ipaddr)));
2497 * Fill RADIUS header fields
2499 packet->code = hdr->code;
2500 packet->id = hdr->id;
2501 memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
2508 * @brief Receive UDP client requests, and fill in
2509 * the basics of a RADIUS_PACKET structure.
2511 RADIUS_PACKET *rad_recv(int fd, int flags)
2515 RADIUS_PACKET *packet;
2518 * Allocate the new request data structure
2520 packet = rad_alloc(NULL, 0);
2522 fr_strerror_printf("out of memory");
2527 sock_flags = MSG_PEEK;
2531 data_len = rad_recvfrom(fd, packet, sock_flags,
2532 &packet->src_ipaddr, &packet->src_port,
2533 &packet->dst_ipaddr, &packet->dst_port);
2536 * Check for socket errors.
2539 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
2540 /* packet->data is NULL */
2544 packet->data_len = data_len; /* unsigned vs signed */
2547 * If the packet is too big, then rad_recvfrom did NOT
2548 * allocate memory. Instead, it just discarded the
2551 if (packet->data_len > MAX_PACKET_LEN) {
2552 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
2553 /* packet->data is NULL */
2559 * Read no data. Continue.
2560 * This check is AFTER the MAX_PACKET_LEN check above, because
2561 * if the packet is larger than MAX_PACKET_LEN, we also have
2562 * packet->data == NULL
2564 if ((packet->data_len == 0) || !packet->data) {
2565 fr_strerror_printf("Empty packet: Socket is not ready.");
2571 * See if it's a well-formed RADIUS packet.
2573 if (!rad_packet_ok(packet, flags)) {
2579 * Remember which socket we read the packet from.
2581 packet->sockfd = fd;
2584 * FIXME: Do even more filtering by only permitting
2585 * certain IP's. The problem is that we don't know
2586 * how to do this properly for all possible clients...
2590 * Explicitely set the VP list to empty.
2594 if (fr_debug_flag) {
2595 char host_ipaddr[128];
2597 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2598 DEBUG("rad_recv: %s packet from host %s port %d",
2599 fr_packet_codes[packet->code],
2600 inet_ntop(packet->src_ipaddr.af,
2601 &packet->src_ipaddr.ipaddr,
2602 host_ipaddr, sizeof(host_ipaddr)),
2605 DEBUG("rad_recv: Packet from host %s port %d code=%d",
2606 inet_ntop(packet->src_ipaddr.af,
2607 &packet->src_ipaddr.ipaddr,
2608 host_ipaddr, sizeof(host_ipaddr)),
2612 DEBUG(", id=%d, length=%d\n",
2613 packet->id, (int) packet->data_len);
2617 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2625 * @brief Verify the Request/Response Authenticator
2626 * (and Message-Authenticator if present) of a packet.
2628 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2635 if (!packet || !packet->data) return -1;
2638 * Before we allocate memory for the attributes, do more
2641 ptr = packet->data + AUTH_HDR_LEN;
2642 length = packet->data_len - AUTH_HDR_LEN;
2643 while (length > 0) {
2644 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
2645 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
2650 default: /* don't do anything. */
2654 * Note that more than one Message-Authenticator
2655 * attribute is invalid.
2657 case PW_MESSAGE_AUTHENTICATOR:
2658 memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
2659 memset(&ptr[2], 0, AUTH_VECTOR_LEN);
2661 switch (packet->code) {
2665 case PW_ACCOUNTING_RESPONSE:
2667 (original->code == PW_STATUS_SERVER)) {
2671 case PW_ACCOUNTING_REQUEST:
2672 case PW_DISCONNECT_REQUEST:
2673 case PW_DISCONNECT_ACK:
2674 case PW_DISCONNECT_NAK:
2675 case PW_COA_REQUEST:
2678 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2682 case PW_AUTHENTICATION_ACK:
2683 case PW_AUTHENTICATION_REJECT:
2684 case PW_ACCESS_CHALLENGE:
2686 fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2689 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2693 fr_hmac_md5(packet->data, packet->data_len,
2694 (uint8_t const *) secret, strlen(secret),
2696 if (rad_digest_cmp(calc_auth_vector, msg_auth_vector,
2697 sizeof(calc_auth_vector)) != 0) {
2699 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator! (Shared secret is incorrect.)",
2700 inet_ntop(packet->src_ipaddr.af,
2701 &packet->src_ipaddr.ipaddr,
2702 buffer, sizeof(buffer)));
2703 /* Silently drop packet, according to RFC 3579 */
2705 } /* else the message authenticator was good */
2708 * Reinitialize Authenticators.
2710 memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2711 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2713 } /* switch over the attributes */
2717 } /* loop over the packet, sanity checking the attributes */
2720 * It looks like a RADIUS packet, but we don't know what it is
2721 * so can't validate the authenticators.
2723 if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2725 fr_strerror_printf("Received Unknown packet code %d "
2726 "from client %s port %d: Cannot validate Request/Response Authenticator.",
2728 inet_ntop(packet->src_ipaddr.af,
2729 &packet->src_ipaddr.ipaddr,
2730 buffer, sizeof(buffer)),
2736 * Calculate and/or verify Request or Response Authenticator.
2738 switch(packet->code) {
2742 case PW_AUTHENTICATION_REQUEST:
2743 case PW_STATUS_SERVER:
2745 * The authentication vector is random
2746 * nonsense, invented by the client.
2750 case PW_COA_REQUEST:
2751 case PW_DISCONNECT_REQUEST:
2752 case PW_ACCOUNTING_REQUEST:
2753 if (calc_acctdigest(packet, secret) > 1) {
2754 fr_strerror_printf("Received %s packet "
2755 "from client %s with invalid Request Authenticator! (Shared secret is incorrect.)",
2756 fr_packet_codes[packet->code],
2757 inet_ntop(packet->src_ipaddr.af,
2758 &packet->src_ipaddr.ipaddr,
2759 buffer, sizeof(buffer)));
2764 /* Verify the reply digest */
2765 case PW_AUTHENTICATION_ACK:
2766 case PW_AUTHENTICATION_REJECT:
2767 case PW_ACCESS_CHALLENGE:
2768 case PW_ACCOUNTING_RESPONSE:
2769 case PW_DISCONNECT_ACK:
2770 case PW_DISCONNECT_NAK:
2773 rcode = calc_replydigest(packet, original, secret);
2775 fr_strerror_printf("Received %s packet "
2776 "from home server %s port %d with invalid Response Authenticator! (Shared secret is incorrect.)",
2777 fr_packet_codes[packet->code],
2778 inet_ntop(packet->src_ipaddr.af,
2779 &packet->src_ipaddr.ipaddr,
2780 buffer, sizeof(buffer)),
2787 fr_strerror_printf("Received Unknown packet code %d "
2788 "from client %s port %d: Cannot validate Request/Response Authenticator",
2790 inet_ntop(packet->src_ipaddr.af,
2791 &packet->src_ipaddr.ipaddr,
2792 buffer, sizeof(buffer)),
2801 static ssize_t data2vp(RADIUS_PACKET const *packet,
2802 RADIUS_PACKET const *original,
2804 DICT_ATTR const *da, uint8_t const *start,
2805 size_t const attrlen, size_t const packetlen,
2809 * @brief convert TLVs to one or more VPs
2811 static ssize_t data2vp_tlvs(RADIUS_PACKET const *packet,
2812 RADIUS_PACKET const *original,
2813 char const *secret, DICT_ATTR const *da,
2814 uint8_t const *start, size_t length,
2817 const uint8_t *data = start;
2818 const DICT_ATTR *child;
2819 VALUE_PAIR *head, **tail;
2821 if (length < 3) return -1; /* type, length, value */
2823 VP_HEXDUMP("tlvs", data, length);
2825 if (rad_tlv_ok(data, length, 1, 1) < 0) return -1;
2830 while (data < (start + length)) {
2833 child = dict_attrbyparent(da, data[0], da->vendor);
2835 unsigned int my_attr, my_vendor;
2837 VP_TRACE("Failed to find child %u of TLV %s\n",
2841 * Get child attr/vendor so that
2842 * we can call unknown attr.
2845 my_vendor = da->vendor;
2847 if (!dict_attr_child(da, &my_attr, &my_vendor)) {
2852 child = dict_attrunknown(my_attr, my_vendor, TRUE);
2859 tlv_len = data2vp(packet, original, secret, child,
2860 data + 2, data[1] - 2, data[1] - 2, tail);
2865 tail = &((*tail)->next);
2874 * @brief Convert a top-level VSA to a VP.
2876 * "length" can be LONGER than just this sub-vsa
2878 static ssize_t data2vp_vsa(RADIUS_PACKET const *packet,
2879 RADIUS_PACKET const *original,
2880 char const *secret, DICT_VENDOR *dv,
2881 uint8_t const *data, size_t length,
2884 unsigned int attribute;
2885 ssize_t attrlen, my_len;
2886 const DICT_ATTR *da;
2889 if (length <= (dv->type + dv->length)) {
2890 fr_strerror_printf("data2vp_vsa: Failure to call rad_tlv_ok");
2897 /* data[0] must be zero */
2898 attribute = data[1] << 16;
2899 attribute |= data[2] << 8;
2900 attribute |= data[3];
2904 attribute = data[0] << 8;
2905 attribute |= data[1];
2909 attribute = data[0];
2913 fr_strerror_printf("data2vp_vsa: Internal sanity check failed");
2917 switch (dv->length) {
2919 /* data[dv->type] must be zero, from rad_tlv_ok() */
2920 attrlen = data[dv->type + 1];
2924 attrlen = data[dv->type];
2932 fr_strerror_printf("data2vp_vsa: Internal sanity check failed");
2937 if (attrlen <= (ssize_t) (dv->type + dv->length)) {
2938 fr_strerror_printf("data2vp_vsa: Failure to call rad_tlv_ok");
2944 * See if the VSA is known.
2946 da = dict_attrbyvalue(attribute, dv->vendorpec);
2947 if (!da) da = dict_attrunknown(attribute, dv->vendorpec, TRUE);
2950 my_len = data2vp(packet, original, secret, da,
2951 data + dv->type + dv->length,
2952 attrlen - (dv->type + dv->length),
2953 attrlen - (dv->type + dv->length),
2955 if (my_len < 0) return my_len;
2962 * @brief Convert a Vendor-Specific WIMAX to vps
2964 * Called ONLY for Vendor-Specific
2966 static ssize_t data2vp_wimax(RADIUS_PACKET const *packet,
2967 RADIUS_PACKET const *original,
2968 char const *secret, uint32_t vendor,
2969 uint8_t const *data,
2970 size_t attrlen, size_t packetlen,
2975 uint8_t *head, *tail;
2976 const uint8_t *frag, *end;
2977 const DICT_ATTR *child;
2979 if (attrlen < 8) return -1;
2981 if (((size_t) (data[5] + 4)) != attrlen) return -1;
2983 child = dict_attrbyvalue(data[4], vendor);
2984 if (!child) return -1;
2986 if ((data[6] & 0x80) == 0) {
2987 rcode = data2vp(packet, original, secret, child,
2988 data + 7, data[5] - 3, data[5] - 3,
2990 if (rcode < 0) return -1;
2995 * Calculate the length of all of the fragments. For
2996 * now, they MUST be contiguous in the packet, and they
2997 * MUST be all of the same VSA, WiMAX, and WiMAX-attr.
2999 * The first fragment doesn't have a RADIUS attribute
3000 * header, so it needs to be treated a little special.
3002 fraglen = data[5] - 3;
3003 frag = data + attrlen;
3004 end = data + packetlen;
3006 while (frag < end) {
3007 int last_frag = FALSE;
3010 (frag[0] != PW_VENDOR_SPECIFIC) ||
3011 (frag[1] < 9) || /* too short for wimax */
3012 ((frag + frag[1]) > end) || /* overflow */
3013 (memcmp(frag + 2, data, 4) != 0) || /* not wimax */
3014 (frag[6] != data[4]) || /* not the same wimax attr */
3015 ((frag[7] + 6) != frag[1])) { /* doesn't fill the attr */
3020 last_frag = ((frag[8] & 0x80) == 0);
3022 fraglen += frag[7] - 3;
3026 head = tail = malloc(fraglen);
3027 if (!head) return -1;
3030 * And again, but faster and looser.
3032 * We copy the first fragment, followed by the rest of
3037 memcpy(tail, frag + 4 + 3, frag[4 + 1] - 3);
3038 tail += frag[4 + 1] - 3;
3039 frag += attrlen; /* should be frag[1] - 7 */
3042 * frag now points to RADIUS attributes
3045 memcpy(tail, frag + 2 + 4 + 3, frag[2 + 4 + 1] - 3);
3046 tail += frag[2 + 4 + 1] - 3;
3048 } while (frag < end);
3050 VP_HEXDUMP("wimax fragments", head, fraglen);
3052 rcode = data2vp(packet, original, secret, child,
3053 head, fraglen, fraglen, pvp);
3055 if (rcode < 0) return rcode;
3062 * @brief Convert a top-level VSA to one or more VPs
3064 static ssize_t data2vp_vsas(RADIUS_PACKET const *packet,
3065 RADIUS_PACKET const *original,
3066 char const *secret, uint8_t const *data,
3067 size_t attrlen, size_t packetlen,
3074 VALUE_PAIR *head, **tail;
3076 if (attrlen > packetlen) return -1;
3077 if (attrlen < 5) return -1; /* vid, value */
3078 if (data[0] != 0) return -1; /* we require 24-bit VIDs */
3080 memcpy(&vendor, data, 4);
3081 vendor = ntohl(vendor);
3082 dv = dict_vendorbyvalue(vendor);
3088 if ((vendor == VENDORPEC_WIMAX) && dv->flags) {
3089 rcode = data2vp_wimax(packet, original, secret, vendor,
3090 data, attrlen, packetlen, pvp);
3095 * VSAs should normally be in TLV format.
3097 if (rad_tlv_ok(data + 4, attrlen - 4,
3098 dv->type, dv->length) < 0) return -1;
3101 * There may be more than one VSA in the
3102 * Vendor-Specific. If so, loop over them all.
3111 while (attrlen > 0) {
3114 vsa_len = data2vp_vsa(packet, original, secret, dv,
3115 data, attrlen, tail);
3118 fr_strerror_printf("Internal sanity check %d", __LINE__);
3121 tail = &((*tail)->next);
3124 packetlen -= vsa_len;
3134 * @brief Create any kind of VP from the attribute contents.
3136 * "length" is AT LEAST the length of this attribute, as we
3137 * expect the caller to have verified the data with
3138 * rad_packet_ok(). "length" may be up to the length of the
3141 * @return -1 on error, or "length".
3143 static ssize_t data2vp(RADIUS_PACKET const *packet,
3144 RADIUS_PACKET const *original,
3146 DICT_ATTR const *da, uint8_t const *start,
3147 size_t const attrlen, size_t const packetlen,
3154 const DICT_ATTR *child;
3157 const uint8_t *data = start;
3158 uint8_t buffer[256];
3160 if (!da || (attrlen > 253) || (attrlen > packetlen) ||
3161 (attrlen > 128*1024)) {
3162 fr_strerror_printf("data2vp: invalid arguments");
3166 VP_HEXDUMP("data2vp", start, attrlen);
3168 VP_TRACE("parent %s len %zu ... %zu\n", da->name, attrlen, packetlen);
3173 * Hacks for CUI. The WiMAX spec says that it can be
3174 * zero length, even though this is forbidden by the
3175 * RADIUS specs. So... we make a special case for it.
3178 if (!((da->vendor == 0) &&
3179 (da->attr == PW_CHARGEABLE_USER_IDENTITY))) {
3186 * Hacks for Coverity. Editing the dictionary
3187 * will break assumptions about CUI. We know
3188 * this, but Coverity doesn't.
3190 if (da->type != PW_TYPE_STRING) return -1;
3193 data = (uint8_t const *) "";
3195 goto alloc_cui; /* skip everything */
3199 * Hacks for tags. If the attribute is capable of
3200 * encoding a tag, and there's room for the tag, and
3201 * there is a tag, or it's encryted with Tunnel-Password,
3202 * then decode the tag.
3204 if (da->flags.has_tag && (datalen > 1) &&
3205 ((data[0] < 0x20) ||
3206 (da->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD))) {
3208 if (da->type == PW_TYPE_STRING) {
3209 memcpy(buffer, data + 1, datalen - 1);
3213 } else if (da->type == PW_TYPE_INTEGER) {
3214 memcpy(buffer, data, attrlen);
3219 return -1; /* only string and integer can have tags */
3226 * Decrypt the attribute.
3228 if (secret && packet && (da->flags.encrypt != FLAG_ENCRYPT_NONE)) {
3229 if (data == start) memcpy(buffer, data, attrlen);
3232 switch (da->flags.encrypt) { /* can't be tagged */
3236 case FLAG_ENCRYPT_USER_PASSWORD:
3238 rad_pwdecode((char *) buffer,
3242 rad_pwdecode((char *) buffer,
3247 datalen = strlen((char *) buffer);
3251 * Tunnel-Password's may go ONLY in response
3252 * packets. They can have a tag, so datalen is
3253 * not the same as attrlen.
3255 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
3256 if (rad_tunnel_pwdecode(buffer, &datalen, secret,
3257 original ? original->vector : nullvector) < 0) {
3263 * Ascend-Send-Secret
3264 * Ascend-Receive-Secret
3266 case FLAG_ENCRYPT_ASCEND_SECRET:
3270 uint8_t my_digest[AUTH_VECTOR_LEN];
3271 make_secret(my_digest,
3274 memcpy(buffer, my_digest,
3276 buffer[AUTH_VECTOR_LEN] = '\0';
3277 datalen = strlen((char *) buffer);
3283 } /* switch over encryption flags */
3287 * Double-check the length after decrypting the
3291 case PW_TYPE_STRING:
3292 case PW_TYPE_OCTETS:
3293 case PW_TYPE_ABINARY:
3296 case PW_TYPE_INTEGER:
3297 case PW_TYPE_IPADDR:
3299 case PW_TYPE_SIGNED:
3300 if (datalen != 4) goto raw;
3303 case PW_TYPE_INTEGER64:
3305 if (datalen != 8) goto raw;
3308 case PW_TYPE_IPV6ADDR:
3309 if (datalen != 16) goto raw;
3312 case PW_TYPE_IPV6PREFIX:
3313 if ((datalen < 2) || (datalen > 18)) goto raw;
3314 if (data[1] > 128) goto raw;
3318 if (datalen != 1) goto raw;
3322 if (datalen != 2) goto raw;
3325 case PW_TYPE_ETHERNET:
3326 if (datalen != 6) goto raw;
3329 case PW_TYPE_COMBO_IP:
3331 child = dict_attrbytype(da->attr, da->vendor,
3333 } else if (datalen == 16) {
3334 child = dict_attrbytype(da->attr, da->vendor,
3339 if (!child) goto raw;
3340 da = child; /* re-write it */
3343 case PW_TYPE_IPV4PREFIX:
3344 if (datalen != 6) goto raw;
3345 if ((data[1] & 0x3f) > 32) goto raw;
3349 * The rest of the data types can cause
3350 * recursion! Ask yourself, "is recursion OK?"
3353 case PW_TYPE_EXTENDED:
3354 if (datalen < 2) goto raw; /* etype, value */
3356 child = dict_attrbyparent(da, data[0], 0);
3357 if (!child) goto raw;
3360 * Recurse to decode the contents, which could be
3361 * a TLV, IPaddr, etc. Note that we decode only
3362 * the current attribute, and we ignore any extra
3365 rcode = data2vp(packet, original, secret, child,
3366 data + 1, attrlen - 1, attrlen - 1, pvp);
3367 if (rcode < 0) goto raw;
3370 case PW_TYPE_LONG_EXTENDED:
3371 if (datalen < 3) goto raw; /* etype, flags, value */
3373 child = dict_attrbyparent(da, data[0], 0);
3374 if (!child) goto raw;
3377 * If there no more fragments, then the contents
3378 * have to be a well-known data type.
3381 if ((data[1] & 0x80) == 0) {
3382 rcode = data2vp(packet, original, secret, child,
3383 data + 2, attrlen - 2, attrlen - 2,
3385 if (rcode < 0) goto raw;
3389 fr_strerror_printf("Internal sanity check %d", __LINE__);
3390 return -1; /* TODO: fixme! */
3393 if (datalen < 6) goto raw; /* vid, vtype, value */
3395 if (data[0] != 0) goto raw; /* we require 24-bit VIDs */
3397 memcpy(&vendor, data, 4);
3398 vendor = ntohl(vendor);
3399 dv = dict_vendorbyvalue(vendor);
3402 child = dict_attrbyparent(da, data[5], vendor);
3403 if (!child) goto raw;
3405 rcode = data2vp(packet, original, secret, child,
3406 data + 5, attrlen - 5, attrlen - 5, pvp);
3407 if (rcode < 0) goto raw;
3412 * We presume that the TLVs all fit into one
3413 * attribute, OR they've already been grouped
3414 * into a contiguous memory buffer.
3416 rcode = data2vp_tlvs(packet, original, secret, da,
3417 data, attrlen, pvp);
3418 if (rcode < 0) goto raw;
3423 * VSAs can be WiMAX, in which case they don't
3424 * fit into one attribute.
3426 rcode = data2vp_vsas(packet, original, secret,
3427 data, attrlen, packetlen, pvp);
3428 if (rcode < 0) goto raw;
3434 * Re-write the attribute to be "raw". It is
3435 * therefore of type "octets", and will be
3438 da = dict_attrunknown(da->attr, da->vendor, TRUE);
3440 fr_strerror_printf("Internal sanity check %d", __LINE__);
3448 if (da->type != PW_TYPE_OCTETS) {
3449 dict_attr_free(&da);
3457 * And now that we've verified the basic type
3458 * information, decode the actual data.
3461 vp = pairalloc(NULL, da);
3464 vp->length = datalen;
3468 case PW_TYPE_STRING:
3469 memcpy(vp->vp_strvalue, data, vp->length);
3470 vp->vp_strvalue[vp->length] = '\0';
3473 case PW_TYPE_OCTETS:
3474 case PW_TYPE_ABINARY:
3475 memcpy(vp->vp_octets, data, vp->length);
3479 vp->vp_integer = data[0];
3484 vp->vp_integer = (data[0] << 8) | data[1];
3487 case PW_TYPE_INTEGER:
3488 memcpy(&vp->vp_integer, data, 4);
3489 vp->vp_integer = ntohl(vp->vp_integer);
3492 case PW_TYPE_INTEGER64:
3493 memcpy(&vp->vp_integer64, data, 8);
3494 vp->vp_integer64 = ntohll(vp->vp_integer64);
3498 memcpy(&vp->vp_date, data, 4);
3499 vp->vp_date = ntohl(vp->vp_date);
3503 case PW_TYPE_IPADDR:
3504 memcpy(&vp->vp_ipaddr, data, 4);
3508 memcpy(&vp->vp_ifid, data, 8);
3511 case PW_TYPE_IPV6ADDR:
3512 memcpy(&vp->vp_ipv6addr, data, 16);
3515 case PW_TYPE_IPV6PREFIX:
3517 * FIXME: double-check that
3518 * (vp->vp_octets[1] >> 3) matches vp->length + 2
3520 memcpy(&vp->vp_ipv6prefix, data, vp->length);
3521 if (vp->length < 18) {
3522 memset(((uint8_t *)vp->vp_ipv6prefix) + vp->length, 0,
3527 case PW_TYPE_IPV4PREFIX:
3528 /* FIXME: do the same double-check as for IPv6Prefix */
3529 memcpy(&vp->vp_ipv4prefix, buffer, sizeof(vp->vp_ipv4prefix));
3532 * /32 means "keep all bits". Otherwise, mask
3535 if ((data[1] & 0x3f) > 32) {
3536 uint32_t addr, mask;
3538 memcpy(&addr, vp->vp_octets + 2, sizeof(addr));
3540 mask <<= (32 - (buffer[1] & 0x3f));
3545 memcpy(vp->vp_octets + 2, &addr, sizeof(addr));
3549 case PW_TYPE_SIGNED: /* overloaded with vp_integer */
3550 memcpy(&vp->vp_integer, buffer, 4);
3551 vp->vp_integer = ntohl(vp->vp_integer);
3556 fr_strerror_printf("Internal sanity check %d", __LINE__);
3567 * @brief Create a "normal" VALUE_PAIR from the given data.
3569 ssize_t rad_attr2vp(RADIUS_PACKET const *packet,
3570 RADIUS_PACKET const *original,
3572 uint8_t const *data, size_t length,
3577 const DICT_ATTR *da;
3579 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3580 fr_strerror_printf("rad_attr2vp: Insufficient data");
3584 da = dict_attrbyvalue(data[0], 0);
3585 if (!da) da = dict_attrunknown(data[0], 0, TRUE);
3588 * Note that we pass the entire length, not just the
3589 * length of this attribute. The Extended or WiMAX
3590 * attributes may have the "continuation" bit set, and
3591 * will thus be more than one attribute in length.
3593 rcode = data2vp(packet, original, secret, da,
3594 data + 2, data[1] - 2, length - 2, pvp);
3595 if (rcode < 0) return rcode;
3602 * @brief Converts data in network byte order to a VP
3603 * @return -1 on error, or the length of the data read
3605 ssize_t rad_data2vp(unsigned int attribute, unsigned int vendor,
3606 uint8_t const *data, size_t length,
3609 const DICT_ATTR *da;
3611 if (!data || (length == 0) || !pvp) return -1;
3613 da = dict_attrbyvalue(attribute, vendor);
3614 if (!da) da = dict_attrunknown(attribute, vendor, TRUE);
3617 return data2vp(NULL, NULL, NULL, da,
3618 data, length, length, pvp);
3622 * @brief Converts vp_data to network byte order
3623 * @return -1 on error, or the length of the value
3625 ssize_t rad_vp2data(VALUE_PAIR const *vp, uint8_t *out, size_t outlen)
3633 fr_strerror_printf("ERROR: rad_vp2data buffer passed too small");
3638 * Short-circuit it for long attributes.
3640 if ((vp->da->type & PW_FLAG_LONG) != 0) goto do_raw;
3642 switch(vp->da->type) {
3643 case PW_TYPE_STRING:
3644 case PW_TYPE_OCTETS:
3646 case PW_TYPE_IPADDR:
3647 case PW_TYPE_IPV6ADDR:
3648 case PW_TYPE_IPV6PREFIX:
3649 case PW_TYPE_IPV4PREFIX:
3650 case PW_TYPE_ABINARY:
3653 memcpy(out, vp->vp_octets, len);
3656 out[0] = vp->vp_integer & 0xff;
3660 out[0] = (vp->vp_integer >> 8) & 0xff;
3661 out[1] = vp->vp_integer & 0xff;
3664 case PW_TYPE_INTEGER:
3665 lvalue = htonl(vp->vp_integer);
3666 memcpy(out, &lvalue, sizeof(lvalue));
3669 case PW_TYPE_INTEGER64:
3670 lvalue64 = htonll(vp->vp_integer64);
3671 memcpy(out, &lvalue64, sizeof(lvalue64));
3675 lvalue = htonl(vp->vp_date);
3676 memcpy(out, &lvalue, sizeof(lvalue));
3679 case PW_TYPE_SIGNED:
3683 slvalue = htonl(vp->vp_signed);
3684 memcpy(out, &slvalue, sizeof(slvalue));
3687 /* unknown type: ignore it */
3689 fr_strerror_printf("ERROR: Unknown attribute type %d",
3698 * @brief Calculate/check digest, and decode radius attributes.
3699 * @return -1 on decoding error, 0 on success
3701 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
3707 radius_packet_t *hdr;
3708 VALUE_PAIR *head, **tail, *vp;
3711 * Extract attribute-value pairs
3713 hdr = (radius_packet_t *)packet->data;
3715 packet_length = packet->data_len - AUTH_HDR_LEN;
3722 * Loop over the attributes, decoding them into VPs.
3724 while (packet_length > 0) {
3728 * This may return many VPs
3730 my_len = rad_attr2vp(packet, original, secret,
3731 ptr, packet_length, &vp);
3746 * VSA's may not have been counted properly in
3747 * rad_packet_ok() above, as it is hard to count
3748 * then without using the dictionary. We
3749 * therefore enforce the limits here, too.
3751 if ((fr_max_attributes > 0) &&
3752 (num_attributes > fr_max_attributes)) {
3753 char host_ipaddr[128];
3756 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
3757 inet_ntop(packet->src_ipaddr.af,
3758 &packet->src_ipaddr.ipaddr,
3759 host_ipaddr, sizeof(host_ipaddr)),
3760 num_attributes, fr_max_attributes);
3765 packet_length -= my_len;
3769 * Merge information from the outside world into our
3772 fr_rand_seed(packet->data, AUTH_HDR_LEN);
3775 * There may be VP's already in the packet. Don't
3776 * destroy them. Instead, add the decoded attributes to
3777 * the tail of the list.
3779 for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
3789 * @brief Encode password.
3791 * We assume that the passwd buffer passed is big enough.
3792 * RFC2138 says the password is max 128 chars, so the size
3793 * of the passwd buffer must be at least 129 characters.
3794 * Preferably it's just MAX_STRING_LEN.
3796 * int *pwlen is updated to the new length of the encrypted
3797 * password - a multiple of 16 bytes.
3799 int rad_pwencode(char *passwd, size_t *pwlen, char const *secret,
3800 uint8_t const *vector)
3802 FR_MD5_CTX context, old;
3803 uint8_t digest[AUTH_VECTOR_LEN];
3804 int i, n, secretlen;
3808 * RFC maximum is 128 bytes.
3810 * If length is zero, pad it out with zeros.
3812 * If the length isn't aligned to 16 bytes,
3813 * zero out the extra data.
3817 if (len > 128) len = 128;
3820 memset(passwd, 0, AUTH_PASS_LEN);
3821 len = AUTH_PASS_LEN;
3822 } else if ((len % AUTH_PASS_LEN) != 0) {
3823 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3824 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3829 * Use the secret to setup the decryption digest
3831 secretlen = strlen(secret);
3833 fr_MD5Init(&context);
3834 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
3835 old = context; /* save intermediate work */
3838 * Encrypt it in place. Don't bother checking
3839 * len, as we've ensured above that it's OK.
3841 for (n = 0; n < len; n += AUTH_PASS_LEN) {
3843 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3844 fr_MD5Final(digest, &context);
3847 fr_MD5Update(&context,
3848 (uint8_t *) passwd + n - AUTH_PASS_LEN,
3850 fr_MD5Final(digest, &context);
3853 for (i = 0; i < AUTH_PASS_LEN; i++) {
3854 passwd[i + n] ^= digest[i];
3862 * @brief Decode password.
3864 int rad_pwdecode(char *passwd, size_t pwlen, char const *secret,
3865 uint8_t const *vector)
3867 FR_MD5_CTX context, old;
3868 uint8_t digest[AUTH_VECTOR_LEN];
3870 size_t n, secretlen;
3873 * The RFC's say that the maximum is 128.
3874 * The buffer we're putting it into above is 254, so
3875 * we don't need to do any length checking.
3877 if (pwlen > 128) pwlen = 128;
3882 if (pwlen == 0) goto done;
3885 * Use the secret to setup the decryption digest
3887 secretlen = strlen(secret);
3889 fr_MD5Init(&context);
3890 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
3891 old = context; /* save intermediate work */
3894 * The inverse of the code above.
3896 for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3898 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3899 fr_MD5Final(digest, &context);
3902 if (pwlen > AUTH_PASS_LEN) {
3903 fr_MD5Update(&context, (uint8_t *) passwd,
3907 fr_MD5Final(digest, &context);
3910 if (pwlen > (n + AUTH_PASS_LEN)) {
3911 fr_MD5Update(&context, (uint8_t *) passwd + n,
3916 for (i = 0; i < AUTH_PASS_LEN; i++) {
3917 passwd[i + n] ^= digest[i];
3922 passwd[pwlen] = '\0';
3923 return strlen(passwd);
3928 * @brief Encode Tunnel-Password attributes when sending them out on the wire.
3930 * int *pwlen is updated to the new length of the encrypted
3931 * password - a multiple of 16 bytes.
3933 * This is per RFC-2868 which adds a two char SALT to the initial intermediate
3936 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, char const *secret,
3937 uint8_t const *vector)
3939 uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
3940 unsigned char digest[AUTH_VECTOR_LEN];
3942 int i, n, secretlen;
3947 if (len > 127) len = 127;
3950 * Shift the password 3 positions right to place a salt and original
3951 * length, tag will be added automatically on packet send
3953 for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
3957 * save original password length as first password character;
3964 * Generate salt. The RFC's say:
3966 * The high bit of salt[0] must be set, each salt in a
3967 * packet should be unique, and they should be random
3969 * So, we set the high bit, add in a counter, and then
3970 * add in some CSPRNG data. should be OK..
3972 salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
3973 (fr_rand() & 0x07));
3974 salt[1] = fr_rand();
3977 * Padd password to multiple of AUTH_PASS_LEN bytes.
3979 n = len % AUTH_PASS_LEN;
3981 n = AUTH_PASS_LEN - n;
3982 for (; n > 0; n--, len++)
3985 /* set new password length */
3989 * Use the secret to setup the decryption digest
3991 secretlen = strlen(secret);
3992 memcpy(buffer, secret, secretlen);
3994 for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
3996 memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
3997 memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
3998 fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
4000 memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
4001 fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
4004 for (i = 0; i < AUTH_PASS_LEN; i++) {
4005 passwd[i + n2] ^= digest[i];
4013 * @brief Decode Tunnel-Password encrypted attributes.
4015 * Defined in RFC-2868, this uses a two char SALT along with the
4016 * initial intermediate value, to differentiate it from the
4019 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, char const *secret,
4020 uint8_t const *vector)
4022 FR_MD5_CTX context, old;
4023 uint8_t digest[AUTH_VECTOR_LEN];
4025 unsigned i, n, len, reallen;
4030 * We need at least a salt.
4033 fr_strerror_printf("tunnel password is too short");
4038 * There's a salt, but no password. Or, there's a salt
4039 * and a 'data_len' octet. It's wrong, but at least we
4040 * can figure out what it means: the password is empty.
4042 * Note that this means we ignore the 'data_len' field,
4043 * if the attribute length tells us that there's no
4044 * more data. So the 'data_len' field may be wrong,
4053 len -= 2; /* discount the salt */
4056 * Use the secret to setup the decryption digest
4058 secretlen = strlen(secret);
4060 fr_MD5Init(&context);
4061 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
4062 old = context; /* save intermediate work */
4065 * Set up the initial key:
4067 * b(1) = MD5(secret + vector + salt)
4069 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4070 fr_MD5Update(&context, passwd, 2);
4073 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4077 fr_MD5Final(digest, &context);
4082 * A quick check: decrypt the first octet
4083 * of the password, which is the
4084 * 'data_len' field. Ensure it's sane.
4086 reallen = passwd[2] ^ digest[0];
4087 if (reallen >= len) {
4088 fr_strerror_printf("tunnel password is too long for the attribute");
4092 fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
4096 fr_MD5Final(digest, &context);
4099 fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
4102 for (i = base; i < AUTH_PASS_LEN; i++) {
4103 passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
4108 * See make_tunnel_password, above.
4110 if (reallen > 239) reallen = 239;
4113 passwd[reallen] = 0;
4119 * @brief Encode a CHAP password
4121 * @bug FIXME: might not work with Ascend because
4122 * we use vp->length, and Ascend gear likes
4123 * to send an extra '\0' in the string!
4125 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
4126 VALUE_PAIR *password)
4130 uint8_t string[MAX_STRING_LEN * 2 + 1];
4131 VALUE_PAIR *challenge;
4134 * Sanity check the input parameters
4136 if ((packet == NULL) || (password == NULL)) {
4141 * Note that the password VP can be EITHER
4142 * a User-Password attribute (from a check-item list),
4143 * or a CHAP-Password attribute (the client asking
4144 * the library to encode it).
4152 memcpy(ptr, password->vp_strvalue, password->length);
4153 ptr += password->length;
4154 i += password->length;
4157 * Use Chap-Challenge pair if present,
4158 * Request Authenticator otherwise.
4160 challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0, TAG_ANY);
4162 memcpy(ptr, challenge->vp_strvalue, challenge->length);
4163 i += challenge->length;
4165 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
4166 i += AUTH_VECTOR_LEN;
4170 fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
4177 * @brief Seed the random number generator.
4179 * May be called any number of times.
4181 void fr_rand_seed(void const *data, size_t size)
4186 * Ensure that the pool is initialized.
4188 if (!fr_rand_initialized) {
4191 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
4193 fd = open("/dev/urandom", O_RDONLY);
4199 while (total < sizeof(fr_rand_pool.randrsl)) {
4200 this = read(fd, fr_rand_pool.randrsl,
4201 sizeof(fr_rand_pool.randrsl) - total);
4202 if ((this < 0) && (errno != EINTR)) break;
4203 if (this > 0) total += this;
4207 fr_rand_pool.randrsl[0] = fd;
4208 fr_rand_pool.randrsl[1] = time(NULL);
4209 fr_rand_pool.randrsl[2] = errno;
4212 fr_randinit(&fr_rand_pool, 1);
4213 fr_rand_pool.randcnt = 0;
4214 fr_rand_initialized = 1;
4220 * Hash the user data
4223 if (!hash) hash = fr_rand();
4224 hash = fr_hash_update(data, size, hash);
4226 fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
4231 * @brief Return a 32-bit random number.
4233 uint32_t fr_rand(void)
4238 * Ensure that the pool is initialized.
4240 if (!fr_rand_initialized) {
4241 fr_rand_seed(NULL, 0);
4244 num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
4245 if (fr_rand_pool.randcnt >= 256) {
4246 fr_rand_pool.randcnt = 0;
4247 fr_isaac(&fr_rand_pool);
4254 /** Allocate a new RADIUS_PACKET
4256 * @param ctx the context in which the packet is allocated. May be NULL if
4257 * the packet is not associated with a REQUEST.
4258 * @param newvector if TRUE a new request authenticator will be generated.
4259 * @return a new RADIUS_PACKET or NULL on error.
4261 RADIUS_PACKET *rad_alloc(TALLOC_CTX *ctx, int newvector)
4265 rp = talloc_zero(ctx, RADIUS_PACKET);
4267 fr_strerror_printf("out of memory");
4275 uint32_t hash, base;
4278 * Don't expose the actual contents of the random
4282 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
4283 hash = fr_rand() ^ base;
4284 memcpy(rp->vector + i, &hash, sizeof(hash));
4287 fr_rand(); /* stir the pool again */
4292 /** Allocate a new RADIUS_PACKET response
4294 * @param ctx the context in which the packet is allocated. May be NULL if
4295 * the packet is not associated with a REQUEST.
4296 * @param packet The request packet.
4297 * @return a new RADIUS_PACKET or NULL on error.
4299 RADIUS_PACKET *rad_alloc_reply(TALLOC_CTX *ctx, RADIUS_PACKET *packet)
4301 RADIUS_PACKET *reply;
4303 if (!packet) return NULL;
4305 reply = rad_alloc(ctx, 0);
4306 if (!reply) return NULL;
4309 * Initialize the fields from the request.
4311 reply->sockfd = packet->sockfd;
4312 reply->dst_ipaddr = packet->src_ipaddr;
4313 reply->src_ipaddr = packet->dst_ipaddr;
4314 reply->dst_port = packet->src_port;
4315 reply->src_port = packet->dst_port;
4316 reply->id = packet->id;
4317 reply->code = 0; /* UNKNOWN code */
4318 memcpy(reply->vector, packet->vector,
4319 sizeof(reply->vector));
4322 reply->data_len = 0;
4329 * @brief Free a RADIUS_PACKET
4331 void rad_free(RADIUS_PACKET **radius_packet_ptr)
4333 RADIUS_PACKET *radius_packet;
4335 if (!radius_packet_ptr || !*radius_packet_ptr) return;
4336 radius_packet = *radius_packet_ptr;
4338 talloc_free(radius_packet->data); /* not really necessary... */
4340 pairfree(&radius_packet->vps);
4342 talloc_free(radius_packet);
4343 *radius_packet_ptr = NULL;