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.
842 switch(vp->da->type) {
848 fr_strerror_printf("ERROR: Cannot encode NULL data");
855 case PW_TYPE_IPV6ADDR:
856 case PW_TYPE_IPV6PREFIX:
857 case PW_TYPE_IPV4PREFIX:
858 case PW_TYPE_ABINARY:
859 data = (uint8_t const *) &vp->data;
863 len = 1; /* just in case */
864 array[0] = vp->vp_integer & 0xff;
869 len = 2; /* just in case */
870 array[0] = (vp->vp_integer >> 8) & 0xff;
871 array[1] = vp->vp_integer & 0xff;
875 case PW_TYPE_INTEGER:
876 len = 4; /* just in case */
877 lvalue = htonl(vp->vp_integer);
878 memcpy(array, &lvalue, sizeof(lvalue));
882 case PW_TYPE_INTEGER64:
883 len = 8; /* just in case */
884 lvalue64 = htonll(vp->vp_integer64);
885 data = (uint8_t *) &lvalue64;
889 * There are no tagged date attributes.
892 lvalue = htonl(vp->vp_date);
893 data = (uint8_t const *) &lvalue;
894 len = 4; /* just in case */
901 len = 4; /* just in case */
902 slvalue = htonl(vp->vp_signed);
903 memcpy(array, &slvalue, sizeof(slvalue));
908 default: /* unknown type: ignore it */
909 fr_strerror_printf("ERROR: Unknown attribute type %d",
923 * Bound the data to the calling size
925 if (len > (ssize_t) room) len = room;
928 * Encrypt the various password styles
930 * Attributes with encrypted values MUST be less than
933 switch (vp->da->flags.encrypt) {
934 case FLAG_ENCRYPT_USER_PASSWORD:
935 make_passwd(ptr, &len, data, len,
936 secret, packet->vector);
939 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
941 if (vp->da->flags.has_tag) lvalue = 1;
944 * Check if there's enough room. If there isn't,
945 * we discard the attribute.
947 * This is ONLY a problem if we have multiple VSA's
948 * in one Vendor-Specific, though.
950 if (room < (18 + lvalue)) return 0;
952 switch (packet->code) {
953 case PW_AUTHENTICATION_ACK:
954 case PW_AUTHENTICATION_REJECT:
955 case PW_ACCESS_CHALLENGE:
958 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->da->name);
962 if (lvalue) ptr[0] = vp->tag;
963 make_tunnel_passwd(ptr + lvalue, &len, data, len,
965 secret, original->vector);
967 case PW_ACCOUNTING_REQUEST:
968 case PW_DISCONNECT_REQUEST:
971 make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
972 secret, packet->vector);
978 * The code above ensures that this attribute
981 case FLAG_ENCRYPT_ASCEND_SECRET:
982 if (len != 16) return 0;
983 make_secret(ptr, packet->vector, secret, data);
984 len = AUTH_VECTOR_LEN;
989 if (vp->da->flags.has_tag && TAG_VALID(vp->tag)) {
990 if (vp->da->type == PW_TYPE_STRING) {
991 if (len > ((ssize_t) (room - 1))) len = room - 1;
994 } else if (vp->da->type == PW_TYPE_INTEGER) {
996 } /* else it can't be any other type */
998 memcpy(ptr, data, len);
1000 } /* switch over encryption flags */
1003 return len + (ptr - start);
1006 static ssize_t attr_shift(uint8_t const *start, uint8_t const *end,
1007 uint8_t *ptr, int hdr_len, ssize_t len,
1008 int flag_offset, int vsa_offset)
1010 int check_len = len - ptr[1];
1011 int total = len + hdr_len;
1014 * Pass 1: Check if the addition of the headers
1015 * overflows the available room. If so, return
1016 * what we were capable of encoding.
1019 while (check_len > (255 - hdr_len)) {
1021 check_len -= (255 - hdr_len);
1025 * Note that this results in a number of attributes maybe
1026 * being marked as "encoded", but which aren't in the
1027 * packet. Oh well. The solution is to fix the
1028 * "vp2data_any" function to take into account the header
1031 if ((ptr + ptr[1] + total) > end) {
1032 return (ptr + ptr[1]) - start;
1036 * Pass 2: Now that we know there's enough room,
1037 * re-arrange the data to form a set of valid
1038 * RADIUS attributes.
1041 int sublen = 255 - ptr[1];
1043 if (len <= sublen) {
1048 memmove(ptr + 255 + hdr_len, ptr + 255, sublen);
1049 memcpy(ptr + 255, ptr, hdr_len);
1051 if (vsa_offset) ptr[vsa_offset] += sublen;
1052 ptr[flag_offset] |= 0x80;
1056 if (vsa_offset) ptr[vsa_offset] = 3;
1060 if (vsa_offset) ptr[vsa_offset] += len;
1062 return (ptr + ptr[1]) - start;
1067 * @brief Encode an "extended" attribute.
1069 int rad_vp2extended(RADIUS_PACKET const *packet,
1070 RADIUS_PACKET const *original,
1071 char const *secret, VALUE_PAIR const **pvp,
1072 uint8_t *ptr, size_t room)
1076 uint8_t *start = ptr;
1077 const VALUE_PAIR *vp = *pvp;
1079 if (!vp->da->flags.extended) {
1080 fr_strerror_printf("rad_vp2extended called for non-extended attribute");
1085 * The attribute number is encoded into the upper 8 bits
1088 ptr[0] = (vp->da->vendor / FR_MAX_VENDOR) & 0xff;
1090 if (!vp->da->flags.long_extended) {
1091 if (room < 3) return 0;
1094 ptr[2] = vp->da->attr & fr_attr_mask[0];
1097 if (room < 4) return 0;
1100 ptr[2] = vp->da->attr & fr_attr_mask[0];
1105 * Only "flagged" attributes can be longer than one
1108 if (!vp->da->flags.long_extended && (room > 255)) {
1115 if (vp->da->flags.evs) {
1116 uint8_t *evs = ptr + ptr[1];
1118 if (room < (size_t) (ptr[1] + 5)) return 0;
1122 evs[0] = 0; /* always zero */
1123 evs[1] = (vp->da->vendor >> 16) & 0xff;
1124 evs[2] = (vp->da->vendor >> 8) & 0xff;
1125 evs[3] = vp->da->vendor & 0xff;
1126 evs[4] = vp->da->attr & fr_attr_mask[0];
1132 len = vp2data_any(packet, original, secret, 0,
1133 pvp, ptr + ptr[1], room - hdr_len);
1134 if (len <= 0) return len;
1137 * There may be more than 252 octets of data encoded in
1138 * the attribute. If so, move the data up in the packet,
1139 * and copy the existing header over. Set the "M" flag ONLY
1140 * after copying the rest of the data.
1142 if (vp->da->flags.long_extended && (len > (255 - ptr[1]))) {
1143 return attr_shift(start, start + room, ptr, 4, len, 3, 0);
1149 if ((fr_debug_flag > 3) && fr_log_fp) {
1152 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1153 if (!vp->da->flags.long_extended) {
1154 fprintf(fr_log_fp, "%02x ", ptr[2]);
1157 fprintf(fr_log_fp, "%02x %02x ", ptr[2], ptr[3]);
1161 if (vp->da->flags.evs) {
1162 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) %02x ",
1163 ptr[jump], ptr[jump + 1],
1164 ptr[jump + 2], ptr[jump + 3],
1165 ((ptr[jump + 1] << 16) |
1166 (ptr[jump + 2] << 8) |
1172 print_hex_data(ptr + jump, len, 3);
1176 return (ptr + ptr[1]) - start;
1181 * @brief Encode a WiMAX attribute.
1183 int rad_vp2wimax(RADIUS_PACKET const *packet,
1184 RADIUS_PACKET const *original,
1185 char const *secret, VALUE_PAIR const **pvp,
1186 uint8_t *ptr, size_t room)
1191 uint8_t *start = ptr;
1192 const VALUE_PAIR *vp = *pvp;
1195 * Double-check for WiMAX format.
1197 if (!vp->da->flags.wimax) {
1198 fr_strerror_printf("rad_vp2wimax called for non-WIMAX VSA");
1203 * Not enough room for:
1204 * attr, len, vendor-id, vsa, vsalen, continuation
1206 if (room < 9) return 0;
1209 * Build the Vendor-Specific header
1212 ptr[0] = PW_VENDOR_SPECIFIC;
1214 lvalue = htonl(vp->da->vendor);
1215 memcpy(ptr + 2, &lvalue, 4);
1216 ptr[6] = (vp->da->attr & fr_attr_mask[1]);
1218 ptr[8] = 0; /* continuation byte */
1222 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1],
1224 if (len <= 0) return len;
1227 * There may be more than 252 octets of data encoded in
1228 * the attribute. If so, move the data up in the packet,
1229 * and copy the existing header over. Set the "C" flag
1230 * ONLY after copying the rest of the data.
1232 if (len > (255 - ptr[1])) {
1233 return attr_shift(start, start + room, ptr, hdr_len, len, 8, 7);
1240 if ((fr_debug_flag > 3) && fr_log_fp) {
1241 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) %02x %02x %02x ",
1243 ptr[2], ptr[3], ptr[4], ptr[5],
1244 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5],
1245 ptr[6], ptr[7], ptr[8]);
1246 print_hex_data(ptr + 9, len, 3);
1250 return (ptr + ptr[1]) - start;
1254 * @brief Encode an RFC format attribute, with the "concat" flag set.
1256 * If there isn't enough room in the packet, the data is
1259 static ssize_t vp2attr_concat(UNUSED RADIUS_PACKET const *packet,
1260 UNUSED RADIUS_PACKET const *original,
1261 UNUSED char const *secret, VALUE_PAIR const **pvp,
1262 unsigned int attribute, uint8_t *start, size_t room)
1264 uint8_t *ptr = start;
1267 VALUE_PAIR const *vp = *pvp;
1275 if (room <= 2) break;
1282 /* no more than 253 octets */
1283 if (left > 253) left = 253;
1285 /* no more than "room" octets */
1286 if (room < (left + 2)) left = room - 2;
1288 memcpy(ptr + 2, p, left);
1291 if ((fr_debug_flag > 3) && fr_log_fp) {
1292 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1293 print_hex_data(ptr + 2, len, 3);
1308 * @brief Encode an RFC format TLV.
1310 * This could be a standard attribute,
1311 * or a TLV data type. If it's a standard attribute, then
1312 * vp->da->attr == attribute. Otherwise, attribute may be
1315 static ssize_t vp2attr_rfc(RADIUS_PACKET const *packet,
1316 RADIUS_PACKET const *original,
1317 char const *secret, VALUE_PAIR const **pvp,
1318 unsigned int attribute, uint8_t *ptr, size_t room)
1322 if (room <= 2) return 0;
1324 ptr[0] = attribute & 0xff;
1327 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1329 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1], room);
1330 if (len <= 0) return len;
1335 if ((fr_debug_flag > 3) && fr_log_fp) {
1336 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1337 print_hex_data(ptr + 2, len, 3);
1346 * @brief Encode a VSA which is a TLV. If it's in the RFC format, call
1347 * vp2attr_rfc. Otherwise, encode it here.
1349 static ssize_t vp2attr_vsa(RADIUS_PACKET const *packet,
1350 RADIUS_PACKET const *original,
1351 char const *secret, VALUE_PAIR const **pvp,
1352 unsigned int attribute, unsigned int vendor,
1353 uint8_t *ptr, size_t room)
1357 const VALUE_PAIR *vp = *pvp;
1360 * Unknown vendor: RFC format.
1361 * Known vendor and RFC format: go do that.
1363 dv = dict_vendorbyvalue(vendor);
1365 (!vp->da->flags.is_tlv && (dv->type == 1) && (dv->length == 1))) {
1366 return vp2attr_rfc(packet, original, secret, pvp,
1367 attribute, ptr, room);
1372 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1373 " type %u", (unsigned) dv->type);
1377 ptr[0] = 0; /* attr must be 24-bit */
1378 ptr[1] = (attribute >> 16) & 0xff;
1379 ptr[2] = (attribute >> 8) & 0xff;
1380 ptr[3] = attribute & 0xff;
1384 ptr[0] = (attribute >> 8) & 0xff;
1385 ptr[1] = attribute & 0xff;
1389 ptr[0] = attribute & 0xff;
1393 switch (dv->length) {
1395 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1396 " length %u", (unsigned) dv->length);
1404 ptr[dv->type + 1] = dv->type + 2;
1408 ptr[dv->type] = dv->type + 1;
1413 if (room > ((unsigned) 255 - (dv->type + dv->length))) {
1414 room = 255 - (dv->type + dv->length);
1417 len = vp2data_any(packet, original, secret, 0, pvp,
1418 ptr + dv->type + dv->length, room);
1419 if (len <= 0) return len;
1421 if (dv->length) ptr[dv->type + dv->length - 1] += len;
1424 if ((fr_debug_flag > 3) && fr_log_fp) {
1430 if ((fr_debug_flag > 3) && fr_log_fp)
1431 fprintf(fr_log_fp, "\t\t%02x%02x%02x%02x ",
1432 ptr[0], ptr[1], ptr[2], ptr[3]);
1436 if ((fr_debug_flag > 3) && fr_log_fp)
1437 fprintf(fr_log_fp, "\t\t%02x%02x ",
1442 if ((fr_debug_flag > 3) && fr_log_fp)
1443 fprintf(fr_log_fp, "\t\t%02x ", ptr[0]);
1447 switch (dv->length) {
1452 fprintf(fr_log_fp, " ");
1456 fprintf(fr_log_fp, "%02x ",
1461 fprintf(fr_log_fp, "%02x%02x ",
1462 ptr[dv->type], ptr[dv->type] + 1);
1466 print_hex_data(ptr + dv->type + dv->length, len, 3);
1470 return dv->type + dv->length + len;
1475 * @brief Encode a Vendor-Specific attribute.
1477 int rad_vp2vsa(RADIUS_PACKET const *packet, RADIUS_PACKET const *original,
1478 char const *secret, VALUE_PAIR const **pvp, uint8_t *ptr,
1483 const VALUE_PAIR *vp = *pvp;
1486 * Double-check for WiMAX format.
1488 if (vp->da->flags.wimax) {
1489 return rad_vp2wimax(packet, original, secret, pvp,
1493 if (vp->da->vendor > FR_MAX_VENDOR) {
1494 fr_strerror_printf("rad_vp2vsa: Invalid arguments");
1499 * Not enough room for:
1500 * attr, len, vendor-id
1502 if (room < 6) return 0;
1505 * Build the Vendor-Specific header
1507 ptr[0] = PW_VENDOR_SPECIFIC;
1509 lvalue = htonl(vp->da->vendor);
1510 memcpy(ptr + 2, &lvalue, 4);
1512 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1514 len = vp2attr_vsa(packet, original, secret, pvp,
1515 vp->da->attr, vp->da->vendor,
1516 ptr + ptr[1], room);
1517 if (len < 0) return len;
1520 if ((fr_debug_flag > 3) && fr_log_fp) {
1521 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) ",
1523 ptr[2], ptr[3], ptr[4], ptr[5],
1524 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5]);
1525 print_hex_data(ptr + 6, len, 3);
1536 * @brief Encode an RFC standard attribute 1..255
1538 int rad_vp2rfc(RADIUS_PACKET const *packet,
1539 RADIUS_PACKET const *original,
1540 char const *secret, VALUE_PAIR const **pvp,
1541 uint8_t *ptr, size_t room)
1543 const VALUE_PAIR *vp = *pvp;
1545 if (vp->da->vendor != 0) {
1546 fr_strerror_printf("rad_vp2rfc called with VSA");
1550 if ((vp->da->attr == 0) || (vp->da->attr > 255)) {
1551 fr_strerror_printf("rad_vp2rfc called with non-standard attribute %u", vp->da->attr);
1556 * Only CUI is allowed to have zero length.
1559 if ((vp->length == 0) &&
1560 (vp->da->attr == PW_CHARGEABLE_USER_IDENTITY)) {
1561 ptr[0] = PW_CHARGEABLE_USER_IDENTITY;
1569 * Message-Authenticator is hard-coded.
1571 if (vp->da->attr == PW_MESSAGE_AUTHENTICATOR) {
1572 if (room < 18) return -1;
1575 ptr[0] = PW_MESSAGE_AUTHENTICATOR;
1577 memset(ptr + 2, 0, 16);
1579 if ((fr_debug_flag > 3) && fr_log_fp) {
1580 fprintf(fr_log_fp, "\t\t50 12 ...\n");
1584 *pvp = (*pvp)->next;
1589 * EAP-Message is special.
1591 if (vp->da->flags.concat && (vp->length > 253)) {
1592 return vp2attr_concat(packet, original, secret, pvp, vp->da->attr,
1596 return vp2attr_rfc(packet, original, secret, pvp, vp->da->attr,
1600 static ssize_t rad_vp2rfctlv(RADIUS_PACKET const *packet,
1601 RADIUS_PACKET const *original,
1602 char const *secret, VALUE_PAIR const **pvp,
1603 uint8_t *start, size_t room)
1606 const VALUE_PAIR *vp = *pvp;
1608 if (!vp->da->flags.is_tlv) {
1609 fr_strerror_printf("rad_vp2rfctlv: attr is not a TLV");
1613 if ((vp->da->vendor & (FR_MAX_VENDOR - 1)) != 0) {
1614 fr_strerror_printf("rad_vp2rfctlv: attr is not an RFC TLV");
1618 if (room < 5) return 0;
1621 * Encode the first level of TLVs
1623 start[0] = (vp->da->vendor / FR_MAX_VENDOR) & 0xff;
1625 start[2] = vp->da->attr & fr_attr_mask[0];
1628 len = vp2data_any(packet, original, secret, 0, pvp,
1629 start + 4, room - 4);
1630 if (len <= 0) return len;
1643 * @brief Parse a data structure into a RADIUS attribute.
1645 int rad_vp2attr(RADIUS_PACKET const *packet, RADIUS_PACKET const *original,
1646 char const *secret, VALUE_PAIR const **pvp, uint8_t *start,
1649 const VALUE_PAIR *vp;
1651 if (!pvp || !*pvp || !start || (room <= 2)) return -1;
1656 * RFC format attributes take the fast path.
1658 if (!vp->da->vendor) {
1659 if (vp->da->attr > 255) return 0;
1661 return rad_vp2rfc(packet, original, secret, pvp,
1665 if (vp->da->flags.extended) {
1666 return rad_vp2extended(packet, original, secret, pvp,
1671 * The upper 8 bits of the vendor number are the standard
1672 * space attribute which is a TLV.
1674 if ((vp->da->vendor & (FR_MAX_VENDOR - 1)) == 0) {
1675 return rad_vp2rfctlv(packet, original, secret, pvp,
1679 if (vp->da->flags.wimax) {
1680 return rad_vp2wimax(packet, original, secret, pvp,
1684 return rad_vp2vsa(packet, original, secret, pvp,
1690 * @brief Encode a packet.
1692 int rad_encode(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
1695 radius_packet_t *hdr;
1697 uint16_t total_length;
1699 const VALUE_PAIR *reply;
1701 char ip_src_buffer[128];
1702 char ip_dst_buffer[128];
1705 * A 4K packet, aligned on 64-bits.
1707 uint64_t data[MAX_PACKET_LEN / sizeof(uint64_t)];
1709 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1710 what = fr_packet_codes[packet->code];
1715 DEBUG("Sending %s of id %d from %s port %u to %s port %u\n",
1717 inet_ntop(packet->src_ipaddr.af,
1718 &packet->src_ipaddr.ipaddr,
1719 ip_src_buffer, sizeof(ip_src_buffer)),
1721 inet_ntop(packet->dst_ipaddr.af,
1722 &packet->dst_ipaddr.ipaddr,
1723 ip_dst_buffer, sizeof(ip_dst_buffer)),
1727 * Double-check some things based on packet code.
1729 switch (packet->code) {
1730 case PW_AUTHENTICATION_ACK:
1731 case PW_AUTHENTICATION_REJECT:
1732 case PW_ACCESS_CHALLENGE:
1734 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1740 * These packet vectors start off as all zero.
1742 case PW_ACCOUNTING_REQUEST:
1743 case PW_DISCONNECT_REQUEST:
1744 case PW_COA_REQUEST:
1745 memset(packet->vector, 0, sizeof(packet->vector));
1753 * Use memory on the stack, until we know how
1754 * large the packet will be.
1756 hdr = (radius_packet_t *) data;
1759 * Build standard header
1761 hdr->code = packet->code;
1762 hdr->id = packet->id;
1764 memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1766 total_length = AUTH_HDR_LEN;
1769 * Load up the configuration values for the user
1775 * FIXME: Loop twice over the reply list. The first time,
1776 * calculate the total length of data. The second time,
1777 * allocate the memory, and fill in the VP's.
1779 * Hmm... this may be slower than just doing a small
1784 * Loop over the reply attributes for the packet.
1786 reply = packet->vps;
1789 char const *last_name = NULL;
1794 * Ignore non-wire attributes, but allow extended
1797 if ((reply->da->vendor == 0) &&
1798 ((reply->da->attr & 0xFFFF) >= 256) &&
1799 !reply->da->flags.extended && !reply->da->flags.long_extended) {
1802 * Permit the admin to send BADLY formatted
1803 * attributes with a debug build.
1805 if (reply->da->attr == PW_RAW_ATTRIBUTE) {
1806 memcpy(ptr, reply->vp_octets, reply->length);
1807 len = reply->length;
1808 reply = reply->next;
1812 reply = reply->next;
1817 * Set the Message-Authenticator to the correct
1818 * length and initial value.
1820 if (reply->da->attr == PW_MESSAGE_AUTHENTICATOR) {
1822 * Cache the offset to the
1823 * Message-Authenticator
1825 packet->offset = total_length;
1828 last_len = reply->length;
1830 last_name = reply->da->name;
1832 len = rad_vp2attr(packet, original, secret, &reply, ptr,
1833 ((uint8_t *) data) + sizeof(data) - ptr);
1834 if (len < 0) return -1;
1837 * Failed to encode the attribute, likely because
1838 * the packet is full.
1841 if (last_len != 0) {
1842 fr_strerror_printf("WARNING: Failed encoding attribute %s\n", last_name);
1844 fr_strerror_printf("WARNING: Skipping zero-length attribute %s\n", last_name);
1849 next: /* Used only for Raw-Attribute */
1852 total_length += len;
1853 } /* done looping over all attributes */
1856 * Fill in the rest of the fields, and copy the data over
1857 * from the local stack to the newly allocated memory.
1859 * Yes, all this 'memcpy' is slow, but it means
1860 * that we only allocate the minimum amount of
1861 * memory for a request.
1863 packet->data_len = total_length;
1864 packet->data = talloc_array(packet, uint8_t, packet->data_len);
1865 if (!packet->data) {
1866 fr_strerror_printf("Out of memory");
1870 memcpy(packet->data, hdr, packet->data_len);
1871 hdr = (radius_packet_t *) packet->data;
1873 total_length = htons(total_length);
1874 memcpy(hdr->length, &total_length, sizeof(total_length));
1881 * @brief Sign a previously encoded packet.
1883 int rad_sign(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
1886 radius_packet_t *hdr = (radius_packet_t *)packet->data;
1889 * It wasn't assigned an Id, this is bad!
1891 if (packet->id < 0) {
1892 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1896 if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1897 (packet->offset < 0)) {
1898 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1903 * If there's a Message-Authenticator, update it
1904 * now, BEFORE updating the authentication vector.
1906 if (packet->offset > 0) {
1907 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1909 switch (packet->code) {
1910 case PW_ACCOUNTING_RESPONSE:
1911 if (original && original->code == PW_STATUS_SERVER) {
1915 case PW_ACCOUNTING_REQUEST:
1916 case PW_DISCONNECT_REQUEST:
1917 case PW_DISCONNECT_ACK:
1918 case PW_DISCONNECT_NAK:
1919 case PW_COA_REQUEST:
1922 memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1926 case PW_AUTHENTICATION_ACK:
1927 case PW_AUTHENTICATION_REJECT:
1928 case PW_ACCESS_CHALLENGE:
1930 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1933 memcpy(hdr->vector, original->vector,
1937 default: /* others have vector already set to zero */
1943 * Set the authentication vector to zero,
1944 * calculate the HMAC, and put it
1945 * into the Message-Authenticator
1948 fr_hmac_md5(packet->data, packet->data_len,
1949 (uint8_t const *) secret, strlen(secret),
1951 memcpy(packet->data + packet->offset + 2,
1952 calc_auth_vector, AUTH_VECTOR_LEN);
1955 * Copy the original request vector back
1956 * to the raw packet.
1958 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1962 * Switch over the packet code, deciding how to
1965 switch (packet->code) {
1967 * Request packets are not signed, bur
1968 * have a random authentication vector.
1970 case PW_AUTHENTICATION_REQUEST:
1971 case PW_STATUS_SERVER:
1975 * Reply packets are signed with the
1976 * authentication vector of the request.
1983 fr_MD5Init(&context);
1984 fr_MD5Update(&context, packet->data, packet->data_len);
1985 fr_MD5Update(&context, (uint8_t const *) secret,
1987 fr_MD5Final(digest, &context);
1989 memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1990 memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1993 }/* switch over packet codes */
1999 * @brief Reply to the request. Also attach
2000 * reply attribute value pairs and any user message provided.
2002 int rad_send(RADIUS_PACKET *packet, RADIUS_PACKET const *original,
2007 char ip_src_buffer[128];
2008 char ip_dst_buffer[128];
2011 * Maybe it's a fake packet. Don't send it.
2013 if (!packet || (packet->sockfd < 0)) {
2017 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2018 what = fr_packet_codes[packet->code];
2024 * First time through, allocate room for the packet
2026 if (!packet->data) {
2028 * Encode the packet.
2030 if (rad_encode(packet, original, secret) < 0) {
2035 * Re-sign it, including updating the
2036 * Message-Authenticator.
2038 if (rad_sign(packet, original, secret) < 0) {
2043 * If packet->data points to data, then we print out
2044 * the VP list again only for debugging.
2046 } else if (fr_debug_flag) {
2047 DEBUG("Sending %s of id %d from %s port %u to %s port %u\n", what,
2049 inet_ntop(packet->src_ipaddr.af,
2050 &packet->src_ipaddr.ipaddr,
2051 ip_src_buffer, sizeof(ip_src_buffer)),
2053 inet_ntop(packet->dst_ipaddr.af,
2054 &packet->dst_ipaddr.ipaddr,
2055 ip_dst_buffer, sizeof(ip_dst_buffer)),
2058 for (reply = packet->vps; reply; reply = reply->next) {
2059 if ((reply->da->vendor == 0) &&
2060 ((reply->da->attr & 0xFFFF) > 0xff)) continue;
2066 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2070 * And send it on it's way.
2072 return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
2073 &packet->src_ipaddr, packet->src_port,
2074 &packet->dst_ipaddr, packet->dst_port);
2078 * @brief Do a comparison of two authentication digests by comparing
2081 * Otherwise, the server can be subject to
2082 * timing attacks that allow attackers find a valid message
2085 * http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
2087 int rad_digest_cmp(uint8_t const *a, uint8_t const *b, size_t length)
2092 for (i = 0; i < length; i++) {
2093 result |= a[i] ^ b[i];
2096 return result; /* 0 is OK, !0 is !OK, just like memcmp */
2101 * @brief Validates the requesting client NAS. Calculates the
2102 * Request Authenticator based on the clients private key.
2104 static int calc_acctdigest(RADIUS_PACKET *packet, char const *secret)
2106 uint8_t digest[AUTH_VECTOR_LEN];
2110 * Zero out the auth_vector in the received packet.
2111 * Then append the shared secret to the received packet,
2112 * and calculate the MD5 sum. This must be the same
2113 * as the original MD5 sum (packet->vector).
2115 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2118 * MD5(packet + secret);
2120 fr_MD5Init(&context);
2121 fr_MD5Update(&context, packet->data, packet->data_len);
2122 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
2123 fr_MD5Final(digest, &context);
2126 * Return 0 if OK, 2 if not OK.
2128 if (rad_digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
2134 * @brief Validates the requesting client NAS. Calculates the
2135 * Response Authenticator based on the clients private key.
2137 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2140 uint8_t calc_digest[AUTH_VECTOR_LEN];
2146 if (original == NULL) {
2151 * Copy the original vector in place.
2153 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2156 * MD5(packet + secret);
2158 fr_MD5Init(&context);
2159 fr_MD5Update(&context, packet->data, packet->data_len);
2160 fr_MD5Update(&context, (uint8_t const *) secret, strlen(secret));
2161 fr_MD5Final(calc_digest, &context);
2164 * Copy the packet's vector back to the packet.
2166 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2169 * Return 0 if OK, 2 if not OK.
2171 if (rad_digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
2177 * @brief Check if a set of RADIUS formatted TLVs are OK.
2179 int rad_tlv_ok(uint8_t const *data, size_t length,
2180 size_t dv_type, size_t dv_length)
2182 const uint8_t *end = data + length;
2184 if ((dv_length > 2) || (dv_type == 0) || (dv_type > 4)) {
2185 fr_strerror_printf("rad_tlv_ok: Invalid arguments");
2189 while (data < end) {
2192 if ((data + dv_type + dv_length) > end) {
2193 fr_strerror_printf("Attribute header overflow");
2199 if ((data[0] == 0) && (data[1] == 0) &&
2200 (data[2] == 0) && (data[3] == 0)) {
2202 fr_strerror_printf("Invalid attribute 0");
2207 fr_strerror_printf("Invalid attribute > 2^24");
2213 if ((data[0] == 0) && (data[1] == 0)) goto zero;
2217 if (data[0] == 0) goto zero;
2221 fr_strerror_printf("Internal sanity check failed");
2225 switch (dv_length) {
2230 if (data[dv_type + 1] != 0) {
2231 fr_strerror_printf("Attribute is longer than 256 octets");
2236 attrlen = data[dv_type + dv_length - 1];
2241 fr_strerror_printf("Internal sanity check failed");
2245 if (attrlen < (dv_type + dv_length)) {
2246 fr_strerror_printf("Attribute header has invalid length");
2250 if (attrlen > length) {
2251 fr_strerror_printf("Attribute overflows container");
2264 * @brief See if the data pointed to by PTR is a valid RADIUS packet.
2266 * packet is not 'const * const' because we may update data_len,
2267 * if there's more data in the UDP packet than in the RADIUS packet.
2269 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
2274 radius_packet_t *hdr;
2275 char host_ipaddr[128];
2281 * Check for packets smaller than the packet header.
2283 * RFC 2865, Section 3., subsection 'length' says:
2285 * "The minimum length is 20 ..."
2287 if (packet->data_len < AUTH_HDR_LEN) {
2288 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %zu < minimum %d)",
2289 inet_ntop(packet->src_ipaddr.af,
2290 &packet->src_ipaddr.ipaddr,
2291 host_ipaddr, sizeof(host_ipaddr)),
2292 packet->data_len, AUTH_HDR_LEN);
2298 * Check for packets with mismatched size.
2299 * i.e. We've received 128 bytes, and the packet header
2300 * says it's 256 bytes long.
2302 totallen = (packet->data[2] << 8) | packet->data[3];
2303 hdr = (radius_packet_t *)packet->data;
2306 * Code of 0 is not understood.
2307 * Code of 16 or greate is not understood.
2309 if ((hdr->code == 0) ||
2310 (hdr->code >= FR_MAX_PACKET_CODE)) {
2311 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code %d",
2312 inet_ntop(packet->src_ipaddr.af,
2313 &packet->src_ipaddr.ipaddr,
2314 host_ipaddr, sizeof(host_ipaddr)),
2320 * Message-Authenticator is required in Status-Server
2321 * packets, otherwise they can be trivially forged.
2323 if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
2326 * It's also required if the caller asks for it.
2328 if (flags) require_ma = 1;
2331 * Repeat the length checks. This time, instead of
2332 * looking at the data we received, look at the value
2333 * of the 'length' field inside of the packet.
2335 * Check for packets smaller than the packet header.
2337 * RFC 2865, Section 3., subsection 'length' says:
2339 * "The minimum length is 20 ..."
2341 if (totallen < AUTH_HDR_LEN) {
2342 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %zu < minimum %d)",
2343 inet_ntop(packet->src_ipaddr.af,
2344 &packet->src_ipaddr.ipaddr,
2345 host_ipaddr, sizeof(host_ipaddr)),
2346 totallen, AUTH_HDR_LEN);
2351 * And again, for the value of the 'length' field.
2353 * RFC 2865, Section 3., subsection 'length' says:
2355 * " ... and maximum length is 4096."
2357 * HOWEVER. This requirement is for the network layer.
2358 * If the code gets here, we assume that a well-formed
2359 * packet is an OK packet.
2361 * We allow both the UDP data length, and the RADIUS
2362 * "length" field to contain up to 64K of data.
2366 * RFC 2865, Section 3., subsection 'length' says:
2368 * "If the packet is shorter than the Length field
2369 * indicates, it MUST be silently discarded."
2371 * i.e. No response to the NAS.
2373 if (packet->data_len < totallen) {
2374 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %zu octets, packet length says %zu",
2375 inet_ntop(packet->src_ipaddr.af,
2376 &packet->src_ipaddr.ipaddr,
2377 host_ipaddr, sizeof(host_ipaddr)),
2378 packet->data_len, totallen);
2383 * RFC 2865, Section 3., subsection 'length' says:
2385 * "Octets outside the range of the Length field MUST be
2386 * treated as padding and ignored on reception."
2388 if (packet->data_len > totallen) {
2390 * We're shortening the packet below, but just
2391 * to be paranoid, zero out the extra data.
2393 memset(packet->data + totallen, 0, packet->data_len - totallen);
2394 packet->data_len = totallen;
2398 * Walk through the packet's attributes, ensuring that
2399 * they add up EXACTLY to the size of the packet.
2401 * If they don't, then the attributes either under-fill
2402 * or over-fill the packet. Any parsing of the packet
2403 * is impossible, and will result in unknown side effects.
2405 * This would ONLY happen with buggy RADIUS implementations,
2406 * or with an intentional attack. Either way, we do NOT want
2407 * to be vulnerable to this problem.
2410 count = totallen - AUTH_HDR_LEN;
2415 * We need at least 2 bytes to check the
2419 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute header overflows the packet",
2420 inet_ntop(packet->src_ipaddr.af,
2421 &packet->src_ipaddr.ipaddr,
2422 host_ipaddr, sizeof(host_ipaddr)));
2427 * Attribute number zero is NOT defined.
2430 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
2431 inet_ntop(packet->src_ipaddr.af,
2432 &packet->src_ipaddr.ipaddr,
2433 host_ipaddr, sizeof(host_ipaddr)));
2438 * Attributes are at LEAST as long as the ID & length
2439 * fields. Anything shorter is an invalid attribute.
2442 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u too short",
2443 inet_ntop(packet->src_ipaddr.af,
2444 &packet->src_ipaddr.ipaddr,
2445 host_ipaddr, sizeof(host_ipaddr)),
2451 * If there are fewer bytes in the packet than in the
2452 * attribute, it's a bad packet.
2454 if (count < attr[1]) {
2455 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u data overflows the packet",
2456 inet_ntop(packet->src_ipaddr.af,
2457 &packet->src_ipaddr.ipaddr,
2458 host_ipaddr, sizeof(host_ipaddr)),
2464 * Sanity check the attributes for length.
2467 default: /* don't do anything by default */
2471 * If there's an EAP-Message, we require
2472 * a Message-Authenticator.
2474 case PW_EAP_MESSAGE:
2478 case PW_MESSAGE_AUTHENTICATOR:
2479 if (attr[1] != 2 + AUTH_VECTOR_LEN) {
2480 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
2481 inet_ntop(packet->src_ipaddr.af,
2482 &packet->src_ipaddr.ipaddr,
2483 host_ipaddr, sizeof(host_ipaddr)),
2492 * FIXME: Look up the base 255 attributes in the
2493 * dictionary, and switch over their type. For
2494 * integer/date/ip, the attribute length SHOULD
2497 count -= attr[1]; /* grab the attribute length */
2499 num_attributes++; /* seen one more attribute */
2503 * If the attributes add up to a packet, it's allowed.
2505 * If not, we complain, and throw the packet away.
2508 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
2509 inet_ntop(packet->src_ipaddr.af,
2510 &packet->src_ipaddr.ipaddr,
2511 host_ipaddr, sizeof(host_ipaddr)));
2516 * If we're configured to look for a maximum number of
2517 * attributes, and we've seen more than that maximum,
2518 * then throw the packet away, as a possible DoS.
2520 if ((fr_max_attributes > 0) &&
2521 (num_attributes > fr_max_attributes)) {
2522 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2523 inet_ntop(packet->src_ipaddr.af,
2524 &packet->src_ipaddr.ipaddr,
2525 host_ipaddr, sizeof(host_ipaddr)),
2526 num_attributes, fr_max_attributes);
2531 * http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
2533 * A packet with an EAP-Message attribute MUST also have
2534 * a Message-Authenticator attribute.
2536 * A Message-Authenticator all by itself is OK, though.
2538 * Similarly, Status-Server packets MUST contain
2539 * Message-Authenticator attributes.
2541 if (require_ma && ! seen_ma) {
2542 fr_strerror_printf("WARNING: Insecure packet from host %s: Packet does not contain required Message-Authenticator attribute",
2543 inet_ntop(packet->src_ipaddr.af,
2544 &packet->src_ipaddr.ipaddr,
2545 host_ipaddr, sizeof(host_ipaddr)));
2550 * Fill RADIUS header fields
2552 packet->code = hdr->code;
2553 packet->id = hdr->id;
2554 memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
2561 * @brief Receive UDP client requests, and fill in
2562 * the basics of a RADIUS_PACKET structure.
2564 RADIUS_PACKET *rad_recv(int fd, int flags)
2568 RADIUS_PACKET *packet;
2571 * Allocate the new request data structure
2573 packet = rad_alloc(NULL, 0);
2575 fr_strerror_printf("out of memory");
2580 sock_flags = MSG_PEEK;
2584 data_len = rad_recvfrom(fd, packet, sock_flags,
2585 &packet->src_ipaddr, &packet->src_port,
2586 &packet->dst_ipaddr, &packet->dst_port);
2589 * Check for socket errors.
2592 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
2593 /* packet->data is NULL */
2597 packet->data_len = data_len; /* unsigned vs signed */
2600 * If the packet is too big, then rad_recvfrom did NOT
2601 * allocate memory. Instead, it just discarded the
2604 if (packet->data_len > MAX_PACKET_LEN) {
2605 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
2606 /* packet->data is NULL */
2612 * Read no data. Continue.
2613 * This check is AFTER the MAX_PACKET_LEN check above, because
2614 * if the packet is larger than MAX_PACKET_LEN, we also have
2615 * packet->data == NULL
2617 if ((packet->data_len == 0) || !packet->data) {
2618 fr_strerror_printf("Empty packet: Socket is not ready.");
2624 * See if it's a well-formed RADIUS packet.
2626 if (!rad_packet_ok(packet, flags)) {
2632 * Remember which socket we read the packet from.
2634 packet->sockfd = fd;
2637 * FIXME: Do even more filtering by only permitting
2638 * certain IP's. The problem is that we don't know
2639 * how to do this properly for all possible clients...
2643 * Explicitely set the VP list to empty.
2647 if (fr_debug_flag) {
2648 char host_ipaddr[128];
2650 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2651 DEBUG("rad_recv: %s packet from host %s port %d",
2652 fr_packet_codes[packet->code],
2653 inet_ntop(packet->src_ipaddr.af,
2654 &packet->src_ipaddr.ipaddr,
2655 host_ipaddr, sizeof(host_ipaddr)),
2658 DEBUG("rad_recv: Packet from host %s port %d code=%d",
2659 inet_ntop(packet->src_ipaddr.af,
2660 &packet->src_ipaddr.ipaddr,
2661 host_ipaddr, sizeof(host_ipaddr)),
2665 DEBUG(", id=%d, length=%d\n",
2666 packet->id, (int) packet->data_len);
2670 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2678 * @brief Verify the Request/Response Authenticator
2679 * (and Message-Authenticator if present) of a packet.
2681 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2688 if (!packet || !packet->data) return -1;
2691 * Before we allocate memory for the attributes, do more
2694 ptr = packet->data + AUTH_HDR_LEN;
2695 length = packet->data_len - AUTH_HDR_LEN;
2696 while (length > 0) {
2697 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
2698 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
2703 default: /* don't do anything. */
2707 * Note that more than one Message-Authenticator
2708 * attribute is invalid.
2710 case PW_MESSAGE_AUTHENTICATOR:
2711 memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
2712 memset(&ptr[2], 0, AUTH_VECTOR_LEN);
2714 switch (packet->code) {
2718 case PW_ACCOUNTING_RESPONSE:
2720 (original->code == PW_STATUS_SERVER)) {
2724 case PW_ACCOUNTING_REQUEST:
2725 case PW_DISCONNECT_REQUEST:
2726 case PW_DISCONNECT_ACK:
2727 case PW_DISCONNECT_NAK:
2728 case PW_COA_REQUEST:
2731 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2735 case PW_AUTHENTICATION_ACK:
2736 case PW_AUTHENTICATION_REJECT:
2737 case PW_ACCESS_CHALLENGE:
2739 fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2742 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2746 fr_hmac_md5(packet->data, packet->data_len,
2747 (uint8_t const *) secret, strlen(secret),
2749 if (rad_digest_cmp(calc_auth_vector, msg_auth_vector,
2750 sizeof(calc_auth_vector)) != 0) {
2752 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator! (Shared secret is incorrect.)",
2753 inet_ntop(packet->src_ipaddr.af,
2754 &packet->src_ipaddr.ipaddr,
2755 buffer, sizeof(buffer)));
2756 /* Silently drop packet, according to RFC 3579 */
2758 } /* else the message authenticator was good */
2761 * Reinitialize Authenticators.
2763 memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2764 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2766 } /* switch over the attributes */
2770 } /* loop over the packet, sanity checking the attributes */
2773 * It looks like a RADIUS packet, but we don't know what it is
2774 * so can't validate the authenticators.
2776 if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2778 fr_strerror_printf("Received Unknown packet code %d "
2779 "from client %s port %d: Cannot validate Request/Response Authenticator.",
2781 inet_ntop(packet->src_ipaddr.af,
2782 &packet->src_ipaddr.ipaddr,
2783 buffer, sizeof(buffer)),
2789 * Calculate and/or verify Request or Response Authenticator.
2791 switch(packet->code) {
2795 case PW_AUTHENTICATION_REQUEST:
2796 case PW_STATUS_SERVER:
2798 * The authentication vector is random
2799 * nonsense, invented by the client.
2803 case PW_COA_REQUEST:
2804 case PW_DISCONNECT_REQUEST:
2805 case PW_ACCOUNTING_REQUEST:
2806 if (calc_acctdigest(packet, secret) > 1) {
2807 fr_strerror_printf("Received %s packet "
2808 "from client %s with invalid Request Authenticator! (Shared secret is incorrect.)",
2809 fr_packet_codes[packet->code],
2810 inet_ntop(packet->src_ipaddr.af,
2811 &packet->src_ipaddr.ipaddr,
2812 buffer, sizeof(buffer)));
2817 /* Verify the reply digest */
2818 case PW_AUTHENTICATION_ACK:
2819 case PW_AUTHENTICATION_REJECT:
2820 case PW_ACCESS_CHALLENGE:
2821 case PW_ACCOUNTING_RESPONSE:
2822 case PW_DISCONNECT_ACK:
2823 case PW_DISCONNECT_NAK:
2826 rcode = calc_replydigest(packet, original, secret);
2828 fr_strerror_printf("Received %s packet "
2829 "from home server %s port %d with invalid Response Authenticator! (Shared secret is incorrect.)",
2830 fr_packet_codes[packet->code],
2831 inet_ntop(packet->src_ipaddr.af,
2832 &packet->src_ipaddr.ipaddr,
2833 buffer, sizeof(buffer)),
2840 fr_strerror_printf("Received Unknown packet code %d "
2841 "from client %s port %d: Cannot validate Request/Response Authenticator",
2843 inet_ntop(packet->src_ipaddr.af,
2844 &packet->src_ipaddr.ipaddr,
2845 buffer, sizeof(buffer)),
2854 static ssize_t data2vp(RADIUS_PACKET *packet,
2855 RADIUS_PACKET const *original,
2857 DICT_ATTR const *da, uint8_t const *start,
2858 size_t const attrlen, size_t const packetlen,
2862 * @brief convert a "concatenated" attribute to one long VP.
2864 static ssize_t data2vp_concat(RADIUS_PACKET *packet,
2865 DICT_ATTR const *da, uint8_t const *start,
2866 size_t const packetlen, VALUE_PAIR **pvp)
2870 uint8_t const *ptr = start;
2871 uint8_t const *end = start + packetlen;
2879 * The packet has already been sanity checked, so we
2880 * don't care about walking off of the end of it.
2883 total += ptr[1] - 2;
2888 * Attributes MUST be consecutive.
2890 if (ptr[0] != attr) break;
2893 vp = pairalloc(packet, da);
2897 vp->vp_octets = p = talloc_array(vp, uint8_t, vp->length);
2905 while (total < vp->length) {
2906 memcpy(p, ptr + 2, ptr[1] - 2);
2908 total += ptr[1] - 2;
2918 * @brief convert TLVs to one or more VPs
2920 static ssize_t data2vp_tlvs(RADIUS_PACKET *packet,
2921 RADIUS_PACKET const *original,
2922 char const *secret, DICT_ATTR const *da,
2923 uint8_t const *start, size_t length,
2926 const uint8_t *data = start;
2927 const DICT_ATTR *child;
2928 VALUE_PAIR *head, **tail;
2930 if (length < 3) return -1; /* type, length, value */
2932 VP_HEXDUMP("tlvs", data, length);
2934 if (rad_tlv_ok(data, length, 1, 1) < 0) return -1;
2939 while (data < (start + length)) {
2942 child = dict_attrbyparent(da, data[0], da->vendor);
2944 unsigned int my_attr, my_vendor;
2946 VP_TRACE("Failed to find child %u of TLV %s\n",
2950 * Get child attr/vendor so that
2951 * we can call unknown attr.
2954 my_vendor = da->vendor;
2956 if (!dict_attr_child(da, &my_attr, &my_vendor)) {
2961 child = dict_attrunknown(my_attr, my_vendor, true);
2968 tlv_len = data2vp(packet, original, secret, child,
2969 data + 2, data[1] - 2, data[1] - 2, tail);
2974 tail = &((*tail)->next);
2983 * @brief Convert a top-level VSA to a VP.
2985 * "length" can be LONGER than just this sub-vsa
2987 static ssize_t data2vp_vsa(RADIUS_PACKET *packet,
2988 RADIUS_PACKET const *original,
2989 char const *secret, DICT_VENDOR *dv,
2990 uint8_t const *data, size_t length,
2993 unsigned int attribute;
2994 ssize_t attrlen, my_len;
2995 const DICT_ATTR *da;
2998 if (length <= (dv->type + dv->length)) {
2999 fr_strerror_printf("data2vp_vsa: Failure to call rad_tlv_ok");
3006 /* data[0] must be zero */
3007 attribute = data[1] << 16;
3008 attribute |= data[2] << 8;
3009 attribute |= data[3];
3013 attribute = data[0] << 8;
3014 attribute |= data[1];
3018 attribute = data[0];
3022 fr_strerror_printf("data2vp_vsa: Internal sanity check failed");
3026 switch (dv->length) {
3028 /* data[dv->type] must be zero, from rad_tlv_ok() */
3029 attrlen = data[dv->type + 1];
3033 attrlen = data[dv->type];
3041 fr_strerror_printf("data2vp_vsa: Internal sanity check failed");
3046 if (attrlen <= (ssize_t) (dv->type + dv->length)) {
3047 fr_strerror_printf("data2vp_vsa: Failure to call rad_tlv_ok");
3053 * See if the VSA is known.
3055 da = dict_attrbyvalue(attribute, dv->vendorpec);
3056 if (!da) da = dict_attrunknown(attribute, dv->vendorpec, true);
3059 my_len = data2vp(packet, original, secret, da,
3060 data + dv->type + dv->length,
3061 attrlen - (dv->type + dv->length),
3062 attrlen - (dv->type + dv->length),
3064 if (my_len < 0) return my_len;
3071 * @brief Convert a fragmented extended attr to a VP
3081 * But for the first fragment, we get passed a pointer to the
3084 static ssize_t data2vp_extended(RADIUS_PACKET *packet,
3085 RADIUS_PACKET const *original,
3086 char const *secret, DICT_ATTR const *da,
3087 uint8_t const *data,
3088 size_t attrlen, size_t packetlen,
3093 uint8_t *head, *tail;
3094 const uint8_t *frag, *end;
3095 uint8_t const *attr;
3097 if (attrlen < 3) return -1;
3100 * Calculate the length of all of the fragments. For
3101 * now, they MUST be contiguous in the packet, and they
3102 * MUST be all of the same TYPE and EXTENDED-TYPE
3105 fraglen = attrlen - 2;
3106 frag = data + attrlen;
3107 end = data + packetlen;
3109 while (frag < end) {
3110 int last_frag = false;
3113 (frag[0] != attr[0]) ||
3114 (frag[1] < 4) || /* too short for long-extended */
3115 (frag[2] != attr[2]) ||
3116 ((frag + frag[1]) > end)) { /* overflow */
3121 last_frag = ((frag[3] & 0x80) == 0);
3123 fraglen += frag[1] - 4;
3127 head = tail = malloc(fraglen);
3128 if (!head) return -1;
3131 * And again, but faster and looser.
3133 * We copy the first fragment, followed by the rest of
3138 while (frag < end) {
3139 memcpy(tail, frag + 4, frag[1] - 4);
3140 tail += frag[1] - 4;
3144 VP_HEXDUMP("long-extended fragments", head, fraglen);
3146 rcode = data2vp(packet, original, secret, da,
3147 head, fraglen, fraglen, pvp);
3149 if (rcode < 0) return rcode;
3155 * @brief Convert a Vendor-Specific WIMAX to vps
3157 * Called ONLY for Vendor-Specific
3159 static ssize_t data2vp_wimax(RADIUS_PACKET *packet,
3160 RADIUS_PACKET const *original,
3161 char const *secret, uint32_t vendor,
3162 uint8_t const *data,
3163 size_t attrlen, size_t packetlen,
3168 uint8_t *head, *tail;
3169 const uint8_t *frag, *end;
3170 DICT_ATTR const *child;
3172 if (attrlen < 8) return -1;
3174 if (((size_t) (data[5] + 4)) != attrlen) return -1;
3176 child = dict_attrbyvalue(data[4], vendor);
3177 if (!child) return -1;
3179 if ((data[6] & 0x80) == 0) {
3180 rcode = data2vp(packet, original, secret, child,
3181 data + 7, data[5] - 3, data[5] - 3,
3183 if (rcode < 0) return -1;
3188 * Calculate the length of all of the fragments. For
3189 * now, they MUST be contiguous in the packet, and they
3190 * MUST be all of the same VSA, WiMAX, and WiMAX-attr.
3192 * The first fragment doesn't have a RADIUS attribute
3193 * header, so it needs to be treated a little special.
3195 fraglen = data[5] - 3;
3196 frag = data + attrlen;
3197 end = data + packetlen;
3199 while (frag < end) {
3200 int last_frag = false;
3203 (frag[0] != PW_VENDOR_SPECIFIC) ||
3204 (frag[1] < 9) || /* too short for wimax */
3205 ((frag + frag[1]) > end) || /* overflow */
3206 (memcmp(frag + 2, data, 4) != 0) || /* not wimax */
3207 (frag[6] != data[4]) || /* not the same wimax attr */
3208 ((frag[7] + 6) != frag[1])) { /* doesn't fill the attr */
3213 last_frag = ((frag[8] & 0x80) == 0);
3215 fraglen += frag[7] - 3;
3219 head = tail = malloc(fraglen);
3220 if (!head) return -1;
3223 * And again, but faster and looser.
3225 * We copy the first fragment, followed by the rest of
3230 memcpy(tail, frag + 4 + 3, frag[4 + 1] - 3);
3231 tail += frag[4 + 1] - 3;
3232 frag += attrlen; /* should be frag[1] - 7 */
3235 * frag now points to RADIUS attributes
3238 memcpy(tail, frag + 2 + 4 + 3, frag[2 + 4 + 1] - 3);
3239 tail += frag[2 + 4 + 1] - 3;
3241 } while (frag < end);
3243 VP_HEXDUMP("wimax fragments", head, fraglen);
3245 rcode = data2vp(packet, original, secret, child,
3246 head, fraglen, fraglen, pvp);
3248 if (rcode < 0) return rcode;
3255 * @brief Convert a top-level VSA to one or more VPs
3257 static ssize_t data2vp_vsas(RADIUS_PACKET *packet,
3258 RADIUS_PACKET const *original,
3259 char const *secret, uint8_t const *data,
3260 size_t attrlen, size_t packetlen,
3267 VALUE_PAIR *head, **tail;
3269 if (attrlen > packetlen) return -1;
3270 if (attrlen < 5) return -1; /* vid, value */
3271 if (data[0] != 0) return -1; /* we require 24-bit VIDs */
3273 memcpy(&vendor, data, 4);
3274 vendor = ntohl(vendor);
3275 dv = dict_vendorbyvalue(vendor);
3281 if ((vendor == VENDORPEC_WIMAX) && dv->flags) {
3282 rcode = data2vp_wimax(packet, original, secret, vendor,
3283 data, attrlen, packetlen, pvp);
3288 * VSAs should normally be in TLV format.
3290 if (rad_tlv_ok(data + 4, attrlen - 4,
3291 dv->type, dv->length) < 0) return -1;
3294 * There may be more than one VSA in the
3295 * Vendor-Specific. If so, loop over them all.
3304 while (attrlen > 0) {
3307 vsa_len = data2vp_vsa(packet, original, secret, dv,
3308 data, attrlen, tail);
3311 fr_strerror_printf("Internal sanity check %d", __LINE__);
3314 tail = &((*tail)->next);
3317 packetlen -= vsa_len;
3327 * @brief Create any kind of VP from the attribute contents.
3329 * "length" is AT LEAST the length of this attribute, as we
3330 * expect the caller to have verified the data with
3331 * rad_packet_ok(). "length" may be up to the length of the
3334 * @return -1 on error, or "length".
3336 static ssize_t data2vp(RADIUS_PACKET *packet,
3337 RADIUS_PACKET const *original,
3339 DICT_ATTR const *da, uint8_t const *start,
3340 size_t const attrlen, size_t const packetlen,
3347 const DICT_ATTR *child;
3350 const uint8_t *data = start;
3352 uint8_t buffer[256];
3355 * FIXME: Attrlen can be larger than 253 for extended attrs!
3357 if (!da || (attrlen > packetlen) ||
3358 ((attrlen > 253) && (attrlen != packetlen)) ||
3359 (attrlen > 128*1024)) {
3360 fr_strerror_printf("data2vp: invalid arguments");
3364 VP_HEXDUMP("data2vp", start, attrlen);
3366 VP_TRACE("parent %s len %zu ... %zu\n", da->name, attrlen, packetlen);
3371 * Hacks for CUI. The WiMAX spec says that it can be
3372 * zero length, even though this is forbidden by the
3373 * RADIUS specs. So... we make a special case for it.
3376 if (!((da->vendor == 0) &&
3377 (da->attr == PW_CHARGEABLE_USER_IDENTITY))) {
3384 * Hacks for Coverity. Editing the dictionary
3385 * will break assumptions about CUI. We know
3386 * this, but Coverity doesn't.
3388 if (da->type != PW_TYPE_STRING) return -1;
3391 data = (uint8_t const *) "";
3393 goto alloc_cui; /* skip everything */
3397 * Hacks for tags. If the attribute is capable of
3398 * encoding a tag, and there's room for the tag, and
3399 * there is a tag, or it's encrypted with Tunnel-Password,
3400 * then decode the tag.
3402 if (da->flags.has_tag && (datalen > 1) &&
3403 ((data[0] < 0x20) ||
3404 (da->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD))) {
3406 * Only "short" attributes can be encrypted.
3408 if (datalen >= sizeof(buffer)) return -1;
3410 if (da->type == PW_TYPE_STRING) {
3411 memcpy(buffer, data + 1, datalen - 1);
3415 } else if (da->type == PW_TYPE_INTEGER) {
3416 memcpy(buffer, data, attrlen);
3421 return -1; /* only string and integer can have tags */
3428 * Decrypt the attribute.
3430 if (secret && packet && (da->flags.encrypt != FLAG_ENCRYPT_NONE)) {
3431 if (data == start) memcpy(buffer, data, attrlen);
3434 switch (da->flags.encrypt) { /* can't be tagged */
3438 case FLAG_ENCRYPT_USER_PASSWORD:
3440 rad_pwdecode((char *) buffer,
3444 rad_pwdecode((char *) buffer,
3449 datalen = strlen((char *) buffer);
3453 * Tunnel-Password's may go ONLY in response
3454 * packets. They can have a tag, so datalen is
3455 * not the same as attrlen.
3457 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
3458 if (rad_tunnel_pwdecode(buffer, &datalen, secret,
3459 original ? original->vector : nullvector) < 0) {
3465 * Ascend-Send-Secret
3466 * Ascend-Receive-Secret
3468 case FLAG_ENCRYPT_ASCEND_SECRET:
3472 uint8_t my_digest[AUTH_VECTOR_LEN];
3473 make_secret(my_digest,
3476 memcpy(buffer, my_digest,
3478 buffer[AUTH_VECTOR_LEN] = '\0';
3479 datalen = strlen((char *) buffer);
3485 } /* switch over encryption flags */
3489 * Double-check the length after decrypting the
3493 case PW_TYPE_STRING:
3494 case PW_TYPE_OCTETS:
3497 case PW_TYPE_ABINARY:
3498 if (datalen > sizeof(vp->vp_filter)) goto raw;
3501 case PW_TYPE_INTEGER:
3502 case PW_TYPE_IPADDR:
3504 case PW_TYPE_SIGNED:
3505 if (datalen != 4) goto raw;
3508 case PW_TYPE_INTEGER64:
3510 if (datalen != 8) goto raw;
3513 case PW_TYPE_IPV6ADDR:
3514 if (datalen != 16) goto raw;
3517 case PW_TYPE_IPV6PREFIX:
3518 if ((datalen < 2) || (datalen > 18)) goto raw;
3519 if (data[1] > 128) goto raw;
3523 if (datalen != 1) goto raw;
3527 if (datalen != 2) goto raw;
3530 case PW_TYPE_ETHERNET:
3531 if (datalen != 6) goto raw;
3534 case PW_TYPE_COMBO_IP:
3536 child = dict_attrbytype(da->attr, da->vendor,
3538 } else if (datalen == 16) {
3539 child = dict_attrbytype(da->attr, da->vendor,
3544 if (!child) goto raw;
3545 da = child; /* re-write it */
3548 case PW_TYPE_IPV4PREFIX:
3549 if (datalen != 6) goto raw;
3550 if ((data[1] & 0x3f) > 32) goto raw;
3554 * The rest of the data types can cause
3555 * recursion! Ask yourself, "is recursion OK?"
3558 case PW_TYPE_EXTENDED:
3559 if (datalen < 2) goto raw; /* etype, value */
3561 child = dict_attrbyparent(da, data[0], 0);
3562 if (!child) goto raw;
3565 * Recurse to decode the contents, which could be
3566 * a TLV, IPaddr, etc. Note that we decode only
3567 * the current attribute, and we ignore any extra
3570 rcode = data2vp(packet, original, secret, child,
3571 data + 1, attrlen - 1, attrlen - 1, pvp);
3572 if (rcode < 0) goto raw;
3575 case PW_TYPE_LONG_EXTENDED:
3576 if (datalen < 3) goto raw; /* etype, flags, value */
3578 child = dict_attrbyparent(da, data[0], 0);
3580 if ((data[0] != PW_VENDOR_SPECIFIC) ||
3581 (datalen < (3 + 4 + 1))) {
3582 /* da->attr < 255, da->vendor == 0 */
3583 child = dict_attrunknown(data[0], da->attr * FR_MAX_VENDOR, true);
3586 * Try to find the VSA.
3588 memcpy(&vendor, data + 3, 4);
3589 vendor = ntohl(vendor);
3591 if (vendor == 0) goto raw;
3593 child = dict_attrunknown(data[7], vendor | (da->attr * FR_MAX_VENDOR), true);
3597 fr_strerror_printf("Internal sanity check %d", __LINE__);
3603 * If there no more fragments, then the contents
3604 * have to be a well-known data type.
3607 if ((data[1] & 0x80) == 0) {
3608 rcode = data2vp(packet, original, secret, child,
3609 data + 2, attrlen - 2, attrlen - 2,
3611 if (rcode < 0) goto raw;
3616 * This requires a whole lot more work.
3618 return data2vp_extended(packet, original, secret, child,
3619 start, attrlen, packetlen, pvp);
3622 if (datalen < 6) goto raw; /* vid, vtype, value */
3624 if (data[0] != 0) goto raw; /* we require 24-bit VIDs */
3626 memcpy(&vendor, data, 4);
3627 vendor = ntohl(vendor);
3628 dv = dict_vendorbyvalue(vendor);
3630 child = dict_attrunknown(data[4], da->vendor | vendor, true);
3632 child = dict_attrbyparent(da, data[4], vendor);
3634 child = dict_attrunknown(data[4], da->vendor | vendor, true);
3637 if (!child) goto raw;
3639 rcode = data2vp(packet, original, secret, child,
3640 data + 5, attrlen - 5, attrlen - 5, pvp);
3641 if (rcode < 0) goto raw;
3646 * We presume that the TLVs all fit into one
3647 * attribute, OR they've already been grouped
3648 * into a contiguous memory buffer.
3650 rcode = data2vp_tlvs(packet, original, secret, da,
3651 data, attrlen, pvp);
3652 if (rcode < 0) goto raw;
3657 * VSAs can be WiMAX, in which case they don't
3658 * fit into one attribute.
3660 rcode = data2vp_vsas(packet, original, secret,
3661 data, attrlen, packetlen, pvp);
3662 if (rcode < 0) goto raw;
3668 * Re-write the attribute to be "raw". It is
3669 * therefore of type "octets", and will be
3672 da = dict_attrunknown(da->attr, da->vendor, true);
3674 fr_strerror_printf("Internal sanity check %d", __LINE__);
3682 if (da->type != PW_TYPE_OCTETS) {
3683 dict_attr_free(&da);
3691 * And now that we've verified the basic type
3692 * information, decode the actual data.
3695 vp = pairalloc(packet, da);
3698 vp->length = datalen;
3702 case PW_TYPE_STRING:
3703 p = talloc_array(vp, char, vp->length + 1);
3704 memcpy(p, data, vp->length);
3705 p[vp->length] = '\0';
3706 vp->vp_strvalue = p;
3709 case PW_TYPE_OCTETS:
3710 vp->vp_octets = talloc_memdup(vp, data, vp->length);
3713 case PW_TYPE_ABINARY:
3714 if (vp->length > sizeof(vp->vp_filter)) {
3715 vp->length = sizeof(vp->vp_filter);
3717 memcpy(vp->vp_filter, data, vp->length);
3721 vp->vp_integer = data[0];
3725 vp->vp_integer = (data[0] << 8) | data[1];
3728 case PW_TYPE_INTEGER:
3729 memcpy(&vp->vp_integer, data, 4);
3730 vp->vp_integer = ntohl(vp->vp_integer);
3733 case PW_TYPE_INTEGER64:
3734 memcpy(&vp->vp_integer64, data, 8);
3735 vp->vp_integer64 = ntohll(vp->vp_integer64);
3739 memcpy(&vp->vp_date, data, 4);
3740 vp->vp_date = ntohl(vp->vp_date);
3744 case PW_TYPE_IPADDR:
3745 memcpy(&vp->vp_ipaddr, data, 4);
3749 memcpy(&vp->vp_ifid, data, 8);
3752 case PW_TYPE_IPV6ADDR:
3753 memcpy(&vp->vp_ipv6addr, data, 16);
3756 case PW_TYPE_IPV6PREFIX:
3758 * FIXME: double-check that
3759 * (vp->vp_octets[1] >> 3) matches vp->length + 2
3761 memcpy(&vp->vp_ipv6prefix, data, vp->length);
3762 if (vp->length < 18) {
3763 memset(((uint8_t *)vp->vp_ipv6prefix) + vp->length, 0,
3768 case PW_TYPE_IPV4PREFIX:
3769 /* FIXME: do the same double-check as for IPv6Prefix */
3770 memcpy(&vp->vp_ipv4prefix, buffer, sizeof(vp->vp_ipv4prefix));
3773 * /32 means "keep all bits". Otherwise, mask
3776 if ((data[1] & 0x3f) > 32) {
3777 uint32_t addr, mask;
3779 memcpy(&addr, vp->vp_octets + 2, sizeof(addr));
3781 mask <<= (32 - (buffer[1] & 0x3f));
3786 memcpy(vp->vp_ipv4prefix + 2, &addr, sizeof(addr));
3790 case PW_TYPE_SIGNED: /* overloaded with vp_integer */
3791 memcpy(&vp->vp_integer, buffer, 4);
3792 vp->vp_integer = ntohl(vp->vp_integer);
3797 fr_strerror_printf("Internal sanity check %d", __LINE__);
3808 * @brief Create a "normal" VALUE_PAIR from the given data.
3810 ssize_t rad_attr2vp(RADIUS_PACKET *packet,
3811 RADIUS_PACKET const *original,
3813 uint8_t const *data, size_t length,
3818 const DICT_ATTR *da;
3820 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3821 fr_strerror_printf("rad_attr2vp: Insufficient data");
3825 da = dict_attrbyvalue(data[0], 0);
3826 if (!da) da = dict_attrunknown(data[0], 0, true);
3829 * Pass the entire thing to the decoding function
3831 if (da->flags.concat) {
3832 return data2vp_concat(packet, da, data, length, pvp);
3836 * Note that we pass the entire length, not just the
3837 * length of this attribute. The Extended or WiMAX
3838 * attributes may have the "continuation" bit set, and
3839 * will thus be more than one attribute in length.
3841 rcode = data2vp(packet, original, secret, da,
3842 data + 2, data[1] - 2, length - 2, pvp);
3843 if (rcode < 0) return rcode;
3850 * @brief Converts data in network byte order to a VP
3851 * @return -1 on error, or the length of the data read
3853 ssize_t rad_data2vp(unsigned int attribute, unsigned int vendor,
3854 uint8_t const *data, size_t length,
3857 const DICT_ATTR *da;
3859 if (!data || (length == 0) || !pvp) return -1;
3861 da = dict_attrbyvalue(attribute, vendor);
3862 if (!da) da = dict_attrunknown(attribute, vendor, true);
3865 return data2vp(NULL, NULL, NULL, da,
3866 data, length, length, pvp);
3870 * @brief Converts vp_data to network byte order
3871 * @return -1 on error, or the length of the value
3873 ssize_t rad_vp2data(VALUE_PAIR const *vp, uint8_t *out, size_t outlen)
3881 fr_strerror_printf("ERROR: rad_vp2data buffer passed too small");
3885 switch(vp->da->type) {
3886 case PW_TYPE_STRING:
3887 case PW_TYPE_OCTETS:
3889 memcpy(out, vp->data.ptr, len);
3893 * All of this data is at the same
3897 case PW_TYPE_IPADDR:
3898 case PW_TYPE_IPV6ADDR:
3899 case PW_TYPE_IPV6PREFIX:
3900 case PW_TYPE_IPV4PREFIX:
3901 case PW_TYPE_ABINARY:
3902 memcpy(out, &vp->data, len);
3906 out[0] = vp->vp_integer & 0xff;
3910 out[0] = (vp->vp_integer >> 8) & 0xff;
3911 out[1] = vp->vp_integer & 0xff;
3914 case PW_TYPE_INTEGER:
3915 lvalue = htonl(vp->vp_integer);
3916 memcpy(out, &lvalue, sizeof(lvalue));
3919 case PW_TYPE_INTEGER64:
3920 lvalue64 = htonll(vp->vp_integer64);
3921 memcpy(out, &lvalue64, sizeof(lvalue64));
3925 lvalue = htonl(vp->vp_date);
3926 memcpy(out, &lvalue, sizeof(lvalue));
3929 case PW_TYPE_SIGNED:
3933 slvalue = htonl(vp->vp_signed);
3934 memcpy(out, &slvalue, sizeof(slvalue));
3937 /* unknown type: ignore it */
3939 fr_strerror_printf("ERROR: Unknown attribute type %d",
3948 * @brief Calculate/check digest, and decode radius attributes.
3949 * @return -1 on decoding error, 0 on success
3951 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
3957 radius_packet_t *hdr;
3958 VALUE_PAIR *head, **tail, *vp;
3961 * Extract attribute-value pairs
3963 hdr = (radius_packet_t *)packet->data;
3965 packet_length = packet->data_len - AUTH_HDR_LEN;
3972 * Loop over the attributes, decoding them into VPs.
3974 while (packet_length > 0) {
3978 * This may return many VPs
3980 my_len = rad_attr2vp(packet, original, secret,
3981 ptr, packet_length, &vp);
3996 * VSA's may not have been counted properly in
3997 * rad_packet_ok() above, as it is hard to count
3998 * then without using the dictionary. We
3999 * therefore enforce the limits here, too.
4001 if ((fr_max_attributes > 0) &&
4002 (num_attributes > fr_max_attributes)) {
4003 char host_ipaddr[128];
4006 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
4007 inet_ntop(packet->src_ipaddr.af,
4008 &packet->src_ipaddr.ipaddr,
4009 host_ipaddr, sizeof(host_ipaddr)),
4010 num_attributes, fr_max_attributes);
4015 packet_length -= my_len;
4019 * Merge information from the outside world into our
4022 fr_rand_seed(packet->data, AUTH_HDR_LEN);
4025 * There may be VP's already in the packet. Don't
4026 * destroy them. Instead, add the decoded attributes to
4027 * the tail of the list.
4029 for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
4039 * @brief Encode password.
4041 * We assume that the passwd buffer passed is big enough.
4042 * RFC2138 says the password is max 128 chars, so the size
4043 * of the passwd buffer must be at least 129 characters.
4044 * Preferably it's just MAX_STRING_LEN.
4046 * int *pwlen is updated to the new length of the encrypted
4047 * password - a multiple of 16 bytes.
4049 int rad_pwencode(char *passwd, size_t *pwlen, char const *secret,
4050 uint8_t const *vector)
4052 FR_MD5_CTX context, old;
4053 uint8_t digest[AUTH_VECTOR_LEN];
4054 int i, n, secretlen;
4058 * RFC maximum is 128 bytes.
4060 * If length is zero, pad it out with zeros.
4062 * If the length isn't aligned to 16 bytes,
4063 * zero out the extra data.
4067 if (len > 128) len = 128;
4070 memset(passwd, 0, AUTH_PASS_LEN);
4071 len = AUTH_PASS_LEN;
4072 } else if ((len % AUTH_PASS_LEN) != 0) {
4073 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
4074 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
4079 * Use the secret to setup the decryption digest
4081 secretlen = strlen(secret);
4083 fr_MD5Init(&context);
4084 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
4085 old = context; /* save intermediate work */
4088 * Encrypt it in place. Don't bother checking
4089 * len, as we've ensured above that it's OK.
4091 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4093 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
4094 fr_MD5Final(digest, &context);
4097 fr_MD5Update(&context,
4098 (uint8_t *) passwd + n - AUTH_PASS_LEN,
4100 fr_MD5Final(digest, &context);
4103 for (i = 0; i < AUTH_PASS_LEN; i++) {
4104 passwd[i + n] ^= digest[i];
4112 * @brief Decode password.
4114 int rad_pwdecode(char *passwd, size_t pwlen, char const *secret,
4115 uint8_t const *vector)
4117 FR_MD5_CTX context, old;
4118 uint8_t digest[AUTH_VECTOR_LEN];
4120 size_t n, secretlen;
4123 * The RFC's say that the maximum is 128.
4124 * The buffer we're putting it into above is 254, so
4125 * we don't need to do any length checking.
4127 if (pwlen > 128) pwlen = 128;
4132 if (pwlen == 0) goto done;
4135 * Use the secret to setup the decryption digest
4137 secretlen = strlen(secret);
4139 fr_MD5Init(&context);
4140 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
4141 old = context; /* save intermediate work */
4144 * The inverse of the code above.
4146 for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
4148 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4149 fr_MD5Final(digest, &context);
4152 if (pwlen > AUTH_PASS_LEN) {
4153 fr_MD5Update(&context, (uint8_t *) passwd,
4157 fr_MD5Final(digest, &context);
4160 if (pwlen > (n + AUTH_PASS_LEN)) {
4161 fr_MD5Update(&context, (uint8_t *) passwd + n,
4166 for (i = 0; i < AUTH_PASS_LEN; i++) {
4167 passwd[i + n] ^= digest[i];
4172 passwd[pwlen] = '\0';
4173 return strlen(passwd);
4178 * @brief Encode Tunnel-Password attributes when sending them out on the wire.
4180 * int *pwlen is updated to the new length of the encrypted
4181 * password - a multiple of 16 bytes.
4183 * This is per RFC-2868 which adds a two char SALT to the initial intermediate
4186 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, char const *secret,
4187 uint8_t const *vector)
4189 uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
4190 unsigned char digest[AUTH_VECTOR_LEN];
4192 int i, n, secretlen;
4197 if (len > 127) len = 127;
4200 * Shift the password 3 positions right to place a salt and original
4201 * length, tag will be added automatically on packet send
4203 for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
4207 * save original password length as first password character;
4214 * Generate salt. The RFC's say:
4216 * The high bit of salt[0] must be set, each salt in a
4217 * packet should be unique, and they should be random
4219 * So, we set the high bit, add in a counter, and then
4220 * add in some CSPRNG data. should be OK..
4222 salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
4223 (fr_rand() & 0x07));
4224 salt[1] = fr_rand();
4227 * Padd password to multiple of AUTH_PASS_LEN bytes.
4229 n = len % AUTH_PASS_LEN;
4231 n = AUTH_PASS_LEN - n;
4232 for (; n > 0; n--, len++)
4235 /* set new password length */
4239 * Use the secret to setup the decryption digest
4241 secretlen = strlen(secret);
4242 memcpy(buffer, secret, secretlen);
4244 for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
4246 memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
4247 memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
4248 fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
4250 memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
4251 fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
4254 for (i = 0; i < AUTH_PASS_LEN; i++) {
4255 passwd[i + n2] ^= digest[i];
4263 * @brief Decode Tunnel-Password encrypted attributes.
4265 * Defined in RFC-2868, this uses a two char SALT along with the
4266 * initial intermediate value, to differentiate it from the
4269 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, char const *secret,
4270 uint8_t const *vector)
4272 FR_MD5_CTX context, old;
4273 uint8_t digest[AUTH_VECTOR_LEN];
4275 unsigned i, n, len, reallen;
4280 * We need at least a salt.
4283 fr_strerror_printf("tunnel password is too short");
4288 * There's a salt, but no password. Or, there's a salt
4289 * and a 'data_len' octet. It's wrong, but at least we
4290 * can figure out what it means: the password is empty.
4292 * Note that this means we ignore the 'data_len' field,
4293 * if the attribute length tells us that there's no
4294 * more data. So the 'data_len' field may be wrong,
4303 len -= 2; /* discount the salt */
4306 * Use the secret to setup the decryption digest
4308 secretlen = strlen(secret);
4310 fr_MD5Init(&context);
4311 fr_MD5Update(&context, (uint8_t const *) secret, secretlen);
4312 old = context; /* save intermediate work */
4315 * Set up the initial key:
4317 * b(1) = MD5(secret + vector + salt)
4319 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4320 fr_MD5Update(&context, passwd, 2);
4323 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4327 fr_MD5Final(digest, &context);
4332 * A quick check: decrypt the first octet
4333 * of the password, which is the
4334 * 'data_len' field. Ensure it's sane.
4336 reallen = passwd[2] ^ digest[0];
4337 if (reallen >= len) {
4338 fr_strerror_printf("tunnel password is too long for the attribute");
4342 fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
4346 fr_MD5Final(digest, &context);
4349 fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
4352 for (i = base; i < AUTH_PASS_LEN; i++) {
4353 passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
4358 * See make_tunnel_password, above.
4360 if (reallen > 239) reallen = 239;
4363 passwd[reallen] = 0;
4369 * @brief Encode a CHAP password
4371 * @bug FIXME: might not work with Ascend because
4372 * we use vp->length, and Ascend gear likes
4373 * to send an extra '\0' in the string!
4375 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
4376 VALUE_PAIR *password)
4380 uint8_t string[MAX_STRING_LEN * 2 + 1];
4381 VALUE_PAIR *challenge;
4384 * Sanity check the input parameters
4386 if ((packet == NULL) || (password == NULL)) {
4391 * Note that the password VP can be EITHER
4392 * a User-Password attribute (from a check-item list),
4393 * or a CHAP-Password attribute (the client asking
4394 * the library to encode it).
4402 memcpy(ptr, password->vp_strvalue, password->length);
4403 ptr += password->length;
4404 i += password->length;
4407 * Use Chap-Challenge pair if present,
4408 * Request Authenticator otherwise.
4410 challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0, TAG_ANY);
4412 memcpy(ptr, challenge->vp_strvalue, challenge->length);
4413 i += challenge->length;
4415 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
4416 i += AUTH_VECTOR_LEN;
4420 fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
4427 * @brief Seed the random number generator.
4429 * May be called any number of times.
4431 void fr_rand_seed(void const *data, size_t size)
4436 * Ensure that the pool is initialized.
4438 if (!fr_rand_initialized) {
4441 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
4443 fd = open("/dev/urandom", O_RDONLY);
4449 while (total < sizeof(fr_rand_pool.randrsl)) {
4450 this = read(fd, fr_rand_pool.randrsl,
4451 sizeof(fr_rand_pool.randrsl) - total);
4452 if ((this < 0) && (errno != EINTR)) break;
4453 if (this > 0) total += this;
4457 fr_rand_pool.randrsl[0] = fd;
4458 fr_rand_pool.randrsl[1] = time(NULL);
4459 fr_rand_pool.randrsl[2] = errno;
4462 fr_randinit(&fr_rand_pool, 1);
4463 fr_rand_pool.randcnt = 0;
4464 fr_rand_initialized = 1;
4470 * Hash the user data
4473 if (!hash) hash = fr_rand();
4474 hash = fr_hash_update(data, size, hash);
4476 fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
4481 * @brief Return a 32-bit random number.
4483 uint32_t fr_rand(void)
4488 * Ensure that the pool is initialized.
4490 if (!fr_rand_initialized) {
4491 fr_rand_seed(NULL, 0);
4494 num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
4495 if (fr_rand_pool.randcnt >= 256) {
4496 fr_rand_pool.randcnt = 0;
4497 fr_isaac(&fr_rand_pool);
4504 /** Allocate a new RADIUS_PACKET
4506 * @param ctx the context in which the packet is allocated. May be NULL if
4507 * the packet is not associated with a REQUEST.
4508 * @param newvector if true a new request authenticator will be generated.
4509 * @return a new RADIUS_PACKET or NULL on error.
4511 RADIUS_PACKET *rad_alloc(TALLOC_CTX *ctx, int newvector)
4515 rp = talloc_zero(ctx, RADIUS_PACKET);
4517 fr_strerror_printf("out of memory");
4525 uint32_t hash, base;
4528 * Don't expose the actual contents of the random
4532 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
4533 hash = fr_rand() ^ base;
4534 memcpy(rp->vector + i, &hash, sizeof(hash));
4537 fr_rand(); /* stir the pool again */
4542 /** Allocate a new RADIUS_PACKET response
4544 * @param ctx the context in which the packet is allocated. May be NULL if
4545 * the packet is not associated with a REQUEST.
4546 * @param packet The request packet.
4547 * @return a new RADIUS_PACKET or NULL on error.
4549 RADIUS_PACKET *rad_alloc_reply(TALLOC_CTX *ctx, RADIUS_PACKET *packet)
4551 RADIUS_PACKET *reply;
4553 if (!packet) return NULL;
4555 reply = rad_alloc(ctx, 0);
4556 if (!reply) return NULL;
4559 * Initialize the fields from the request.
4561 reply->sockfd = packet->sockfd;
4562 reply->dst_ipaddr = packet->src_ipaddr;
4563 reply->src_ipaddr = packet->dst_ipaddr;
4564 reply->dst_port = packet->src_port;
4565 reply->src_port = packet->dst_port;
4566 reply->id = packet->id;
4567 reply->code = 0; /* UNKNOWN code */
4568 memcpy(reply->vector, packet->vector,
4569 sizeof(reply->vector));
4572 reply->data_len = 0;
4579 * @brief Free a RADIUS_PACKET
4581 void rad_free(RADIUS_PACKET **radius_packet_ptr)
4583 RADIUS_PACKET *radius_packet;
4585 if (!radius_packet_ptr || !*radius_packet_ptr) return;
4586 radius_packet = *radius_packet_ptr;
4588 talloc_free(radius_packet->data); /* not really necessary... */
4590 pairfree(&radius_packet->vps);
4592 talloc_free(radius_packet);
4593 *radius_packet_ptr = NULL;