2 * radius.c Functions to send/receive radius packets.
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
20 * Copyright 2000-2003,2006 The FreeRADIUS server project
23 #include <freeradius-devel/ident.h>
26 #include <freeradius-devel/libradius.h>
27 #include <freeradius-devel/md5.h>
33 #include <freeradius-devel/udpfromto.h>
41 #define VP_TRACE if (fr_debug_flag) printf
43 #define VP_TRACE(_x, ...)
48 * The RFC says 4096 octets max, and most packets are less than 256.
50 #define MAX_PACKET_LEN 4096
53 * The maximum number of attributes which we allow in an incoming
54 * request. If there are more attributes than this, the request
57 * This helps to minimize the potential for a DoS, when an
58 * attacker spoofs Access-Request packets, which don't have a
59 * Message-Authenticator attribute. This means that the packet
60 * is unsigned, and the attacker can use resources on the server,
61 * even if the end request is rejected.
63 int fr_max_attributes = 0;
64 FILE *fr_log_fp = NULL;
66 typedef struct radius_packet_t {
70 uint8_t vector[AUTH_VECTOR_LEN];
74 static fr_randctx fr_rand_pool; /* across multiple calls */
75 static int fr_rand_initialized = 0;
76 static unsigned int salt_offset = 0;
78 const char *fr_packet_codes[FR_MAX_PACKET_CODE] = {
84 "Accounting-Response",
100 "Resource-Free-Request",
101 "Resource-Free-Response",
102 "Resource-Query-Request",
103 "Resource-Query-Response",
104 "Alternate-Resource-Reclaim-Request",
105 "NAS-Reboot-Request",
106 "NAS-Reboot-Response",
119 "Disconnect-Request",
129 "IP-Address-Allocate",
134 void fr_printf_log(const char *fmt, ...)
139 if ((fr_debug_flag == 0) || !fr_log_fp) {
144 vfprintf(fr_log_fp, fmt, ap);
150 static const char *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";
152 static void print_hex_data(const uint8_t *ptr, int attrlen, int depth)
156 for (i = 0; i < attrlen; i++) {
157 if ((i > 0) && ((i & 0x0f) == 0x00))
158 fprintf(fr_log_fp, "%.*s", depth, tabs);
159 fprintf(fr_log_fp, "%02x ", ptr[i]);
160 if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
162 if ((i & 0x0f) != 0) fprintf(fr_log_fp, "\n");
166 void rad_print_hex(RADIUS_PACKET *packet)
170 if (!packet->data || !fr_log_fp) return;
172 fprintf(fr_log_fp, " Code:\t\t%u\n", packet->data[0]);
173 fprintf(fr_log_fp, " Id:\t\t%u\n", packet->data[1]);
174 fprintf(fr_log_fp, " Length:\t%u\n", ((packet->data[2] << 8) |
176 fprintf(fr_log_fp, " Vector:\t");
177 for (i = 4; i < 20; i++) {
178 fprintf(fr_log_fp, "%02x", packet->data[i]);
180 fprintf(fr_log_fp, "\n");
182 if (packet->data_len > 20) {
185 fprintf(fr_log_fp, " Data:");
187 total = packet->data_len - 20;
188 ptr = packet->data + 20;
192 unsigned int vendor = 0;
194 fprintf(fr_log_fp, "\t\t");
195 if (total < 2) { /* too short */
196 fprintf(fr_log_fp, "%02x\n", *ptr);
200 if (ptr[1] > total) { /* too long */
201 for (i = 0; i < total; i++) {
202 fprintf(fr_log_fp, "%02x ", ptr[i]);
207 fprintf(fr_log_fp, "%02x %02x ", ptr[0], ptr[1]);
208 attrlen = ptr[1] - 2;
210 if ((ptr[0] == PW_VENDOR_SPECIFIC) &&
212 vendor = (ptr[3] << 16) | (ptr[4] << 8) | ptr[5];
213 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) ",
214 ptr[2], ptr[3], ptr[4], ptr[5], vendor);
225 print_hex_data(ptr, attrlen, 3);
227 if ((attrlen & 0x0f) != 0x00) fprintf(fr_log_fp, "\n");
237 * Wrapper for sendto which handles sendfromto, IPv6, and all
238 * possible combinations.
240 static int rad_sendto(int sockfd, void *data, size_t data_len, int flags,
241 fr_ipaddr_t *src_ipaddr, int src_port,
242 fr_ipaddr_t *dst_ipaddr, int dst_port)
245 struct sockaddr_storage dst;
246 socklen_t sizeof_dst;
248 #ifdef WITH_UDPFROMTO
249 struct sockaddr_storage src;
250 socklen_t sizeof_src;
252 fr_ipaddr2sockaddr(src_ipaddr, src_port, &src, &sizeof_src);
254 src_port = src_port; /* -Wunused */
257 if (!fr_ipaddr2sockaddr(dst_ipaddr, dst_port, &dst, &sizeof_dst)) {
261 #ifdef WITH_UDPFROMTO
263 * And if they don't specify a source IP address, don't
266 if (((dst_ipaddr->af == AF_INET) || (dst_ipaddr->af == AF_INET6)) &&
267 (src_ipaddr->af != AF_UNSPEC) &&
268 !fr_inaddr_any(src_ipaddr)) {
269 rcode = sendfromto(sockfd, data, data_len, flags,
270 (struct sockaddr *)&src, sizeof_src,
271 (struct sockaddr *)&dst, sizeof_dst);
275 src_ipaddr = src_ipaddr; /* -Wunused */
279 * No udpfromto, fail gracefully.
281 rcode = sendto(sockfd, data, data_len, flags,
282 (struct sockaddr *) &dst, sizeof_dst);
284 DEBUG("rad_send() failed: %s\n", strerror(errno));
291 void rad_recv_discard(int sockfd)
294 struct sockaddr_storage src;
295 socklen_t sizeof_src = sizeof(src);
297 recvfrom(sockfd, header, sizeof(header), 0,
298 (struct sockaddr *)&src, &sizeof_src);
302 ssize_t rad_recv_header(int sockfd, fr_ipaddr_t *src_ipaddr, int *src_port,
305 ssize_t data_len, packet_len;
307 struct sockaddr_storage src;
308 socklen_t sizeof_src = sizeof(src);
310 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
311 (struct sockaddr *)&src, &sizeof_src);
313 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
318 * Too little data is available, discard the packet.
321 recvfrom(sockfd, header, sizeof(header), 0,
322 (struct sockaddr *)&src, &sizeof_src);
325 } else { /* we got 4 bytes of data. */
327 * See how long the packet says it is.
329 packet_len = (header[2] * 256) + header[3];
332 * The length in the packet says it's less than
333 * a RADIUS header length: discard it.
335 if (packet_len < AUTH_HDR_LEN) {
336 recvfrom(sockfd, header, sizeof(header), 0,
337 (struct sockaddr *)&src, &sizeof_src);
341 * Enforce RFC requirements, for sanity.
342 * Anything after 4k will be discarded.
344 } else if (packet_len > MAX_PACKET_LEN) {
345 recvfrom(sockfd, header, sizeof(header), 0,
346 (struct sockaddr *)&src, &sizeof_src);
352 * Convert AF. If unknown, discard packet.
354 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, src_port)) {
355 recvfrom(sockfd, header, sizeof(header), 0,
356 (struct sockaddr *)&src, &sizeof_src);
363 * The packet says it's this long, but the actual UDP
364 * size could still be smaller.
371 * wrapper for recvfrom, which handles recvfromto, IPv6, and all
372 * possible combinations.
374 static ssize_t rad_recvfrom(int sockfd, uint8_t **pbuf, int flags,
375 fr_ipaddr_t *src_ipaddr, uint16_t *src_port,
376 fr_ipaddr_t *dst_ipaddr, uint16_t *dst_port)
378 struct sockaddr_storage src;
379 struct sockaddr_storage dst;
380 socklen_t sizeof_src = sizeof(src);
381 socklen_t sizeof_dst = sizeof(dst);
388 memset(&src, 0, sizeof_src);
389 memset(&dst, 0, sizeof_dst);
392 * Get address family, etc. first, so we know if we
393 * need to do udpfromto.
395 * FIXME: udpfromto also does this, but it's not
396 * a critical problem.
398 if (getsockname(sockfd, (struct sockaddr *)&dst,
399 &sizeof_dst) < 0) return -1;
402 * Read the length of the packet, from the packet.
403 * This lets us allocate the buffer to use for
404 * reading the rest of the packet.
406 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
407 (struct sockaddr *)&src, &sizeof_src);
409 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
414 * Too little data is available, discard the packet.
417 recvfrom(sockfd, header, sizeof(header), flags,
418 (struct sockaddr *)&src, &sizeof_src);
421 } else { /* we got 4 bytes of data. */
423 * See how long the packet says it is.
425 len = (header[2] * 256) + header[3];
428 * The length in the packet says it's less than
429 * a RADIUS header length: discard it.
431 if (len < AUTH_HDR_LEN) {
432 recvfrom(sockfd, header, sizeof(header), flags,
433 (struct sockaddr *)&src, &sizeof_src);
437 * Enforce RFC requirements, for sanity.
438 * Anything after 4k will be discarded.
440 } else if (len > MAX_PACKET_LEN) {
441 recvfrom(sockfd, header, sizeof(header), flags,
442 (struct sockaddr *)&src, &sizeof_src);
451 * Receive the packet. The OS will discard any data in the
452 * packet after "len" bytes.
454 #ifdef WITH_UDPFROMTO
455 if ((dst.ss_family == AF_INET) || (dst.ss_family == AF_INET6)) {
456 data_len = recvfromto(sockfd, buf, len, flags,
457 (struct sockaddr *)&src, &sizeof_src,
458 (struct sockaddr *)&dst, &sizeof_dst);
462 * No udpfromto, fail gracefully.
464 data_len = recvfrom(sockfd, buf, len, flags,
465 (struct sockaddr *)&src, &sizeof_src);
471 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, &port)) {
473 return -1; /* Unknown address family, Die Die Die! */
477 fr_sockaddr2ipaddr(&dst, sizeof_dst, dst_ipaddr, &port);
481 * Different address families should never happen.
483 if (src.ss_family != dst.ss_family) {
489 * Tell the caller about the data
497 #define AUTH_PASS_LEN (AUTH_VECTOR_LEN)
498 /*************************************************************************
500 * Function: make_secret
502 * Purpose: Build an encrypted secret value to return in a reply
503 * packet. The secret is hidden by xoring with a MD5 digest
504 * created from the shared secret and the authentication
505 * vector. We put them into MD5 in the reverse order from
506 * that used when encrypting passwords to RADIUS.
508 *************************************************************************/
509 static void make_secret(uint8_t *digest, const uint8_t *vector,
510 const char *secret, const uint8_t *value)
515 fr_MD5Init(&context);
516 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
517 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
518 fr_MD5Final(digest, &context);
520 for ( i = 0; i < AUTH_VECTOR_LEN; i++ ) {
521 digest[i] ^= value[i];
525 #define MAX_PASS_LEN (128)
526 static void make_passwd(uint8_t *output, ssize_t *outlen,
527 const uint8_t *input, size_t inlen,
528 const char *secret, const uint8_t *vector)
530 FR_MD5_CTX context, old;
531 uint8_t digest[AUTH_VECTOR_LEN];
532 uint8_t passwd[MAX_PASS_LEN];
537 * If the length is zero, round it up.
541 if (len > MAX_PASS_LEN) len = MAX_PASS_LEN;
543 memcpy(passwd, input, len);
544 memset(passwd + len, 0, sizeof(passwd) - len);
550 else if ((len & 0x0f) != 0) {
556 fr_MD5Init(&context);
557 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
563 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
565 for (n = 0; n < len; n += AUTH_PASS_LEN) {
568 fr_MD5Update(&context,
569 passwd + n - AUTH_PASS_LEN,
573 fr_MD5Final(digest, &context);
574 for (i = 0; i < AUTH_PASS_LEN; i++) {
575 passwd[i + n] ^= digest[i];
579 memcpy(output, passwd, len);
582 static void make_tunnel_passwd(uint8_t *output, ssize_t *outlen,
583 const uint8_t *input, size_t inlen, size_t room,
584 const char *secret, const uint8_t *vector)
586 FR_MD5_CTX context, old;
587 uint8_t digest[AUTH_VECTOR_LEN];
588 uint8_t passwd[MAX_STRING_LEN + AUTH_VECTOR_LEN];
595 if (room > 253) room = 253;
598 * Account for 2 bytes of the salt, and round the room
599 * available down to the nearest multiple of 16. Then,
600 * subtract one from that to account for the length byte,
601 * and the resulting number is the upper bound on the data
604 * We could short-cut this calculation just be forcing
605 * inlen to be no more than 239. It would work for all
606 * VSA's, as we don't pack multiple VSA's into one
609 * However, this calculation is more general, if a little
610 * complex. And it will work in the future for all possible
611 * kinds of weird attribute packing.
614 room -= (room & 0x0f);
617 if (inlen > room) inlen = room;
620 * Length of the encrypted data is password length plus
621 * one byte for the length of the password.
624 if ((len & 0x0f) != 0) {
628 *outlen = len + 2; /* account for the salt */
631 * Copy the password over.
633 memcpy(passwd + 3, input, inlen);
634 memset(passwd + 3 + inlen, 0, sizeof(passwd) - 3 - inlen);
637 * Generate salt. The RFC's say:
639 * The high bit of salt[0] must be set, each salt in a
640 * packet should be unique, and they should be random
642 * So, we set the high bit, add in a counter, and then
643 * add in some CSPRNG data. should be OK..
645 passwd[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
647 passwd[1] = fr_rand();
648 passwd[2] = inlen; /* length of the password string */
650 fr_MD5Init(&context);
651 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
654 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
655 fr_MD5Update(&context, &passwd[0], 2);
657 for (n = 0; n < len; n += AUTH_PASS_LEN) {
660 fr_MD5Update(&context,
661 passwd + 2 + n - AUTH_PASS_LEN,
665 fr_MD5Final(digest, &context);
667 for (i = 0; i < AUTH_PASS_LEN; i++) {
668 passwd[i + 2 + n] ^= digest[i];
671 memcpy(output, passwd, len + 2);
674 extern int fr_attr_max_tlv;
675 extern int fr_attr_shift[];
676 extern int fr_attr_mask[];
678 static int do_next_tlv(const VALUE_PAIR *vp, int nest)
680 unsigned int tlv1, tlv2;
682 if (nest > fr_attr_max_tlv) return 0;
687 * Keep encoding TLVs which have the same scope.
688 * e.g. two attributes of:
689 * ATTR.TLV1.TLV2.TLV3 = data1
690 * ATTR.TLV1.TLV2.TLV4 = data2
691 * both get put into a container of "ATTR.TLV1.TLV2"
695 * Nothing to follow, we're done.
697 if (!vp->next) return 0;
700 * Not from the same vendor, skip it.
702 if (vp->vendor != vp->next->vendor) return 0;
705 * In a different TLV space, skip it.
707 tlv1 = vp->attribute;
708 tlv2 = vp->next->attribute;
710 tlv1 &= ((1 << fr_attr_shift[nest]) - 1);
711 tlv2 &= ((1 << fr_attr_shift[nest]) - 1);
713 if (tlv1 != tlv2) return 0;
719 static ssize_t vp2data_any(const RADIUS_PACKET *packet,
720 const RADIUS_PACKET *original,
721 const char *secret, int nest,
722 const VALUE_PAIR **pvp,
723 uint8_t *start, size_t room);
725 static ssize_t vp2attr_rfc(const RADIUS_PACKET *packet,
726 const RADIUS_PACKET *original,
727 const char *secret, const VALUE_PAIR **pvp,
728 unsigned int attribute, uint8_t *ptr, size_t room);
731 * This is really a sub-function of vp2data_any. It encodes
732 * the *data* portion of the TLV, and assumes that the encapsulating
733 * attribute has already been encoded.
735 static ssize_t vp2data_tlvs(const RADIUS_PACKET *packet,
736 const RADIUS_PACKET *original,
737 const char *secret, int nest,
738 const VALUE_PAIR **pvp,
739 uint8_t *start, size_t room)
743 uint8_t *ptr = start;
744 const VALUE_PAIR *old_vp;
745 const VALUE_PAIR *vp = *pvp;
748 if (nest > fr_attr_max_tlv) {
749 fr_strerror_printf("vp2data_tlvs: attribute nesting overflow");
755 if (room < 2) return ptr - start;
758 ptr[0] = (vp->attribute >> fr_attr_shift[nest]) & fr_attr_mask[nest];
761 VP_TRACE("TLV encoded %s %u\n", vp->name, start[0]);
764 if (room > 255) my_room = 255;
766 len = vp2data_any(packet, original, secret, nest,
767 &vp, ptr + 2, my_room - 2);
768 if (len < 0) return len;
769 if (len == 0) return ptr - start;
770 /* len can NEVER be more than 253 */
775 if ((fr_debug_flag > 3) && fr_log_fp) {
776 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
777 print_hex_data(ptr + 2, len, 3);
785 if (!do_next_tlv(old_vp, nest)) break;
794 * Encodes the data portion of an attribute.
795 * Returns -1 on error, or the length of the data portion.
797 static ssize_t vp2data_any(const RADIUS_PACKET *packet,
798 const RADIUS_PACKET *original,
799 const char *secret, int nest,
800 const VALUE_PAIR **pvp,
801 uint8_t *start, size_t room)
806 uint8_t *ptr = start;
808 const VALUE_PAIR *vp = *pvp;
811 * See if we need to encode a TLV. The low portion of
812 * the attribute has already been placed into the packer.
813 * If there are still attribute bytes left, then go
814 * encode them as TLVs.
816 * If we cared about the stack, we could unroll the loop.
818 VP_TRACE("vp2data_any: %u attr %u -> %u\n",
819 nest, vp->attribute, vp->attribute >> fr_attr_shift[nest + 1]);
820 if (vp->flags.is_tlv && (nest < fr_attr_max_tlv) &&
821 ((vp->attribute >> fr_attr_shift[nest + 1]) != 0)) {
822 return vp2data_tlvs(packet, original, secret, nest + 1, pvp,
825 VP_TRACE("vp2data_any: Encoding %s\n", vp->name);
828 * Set up the default sources for the data.
830 data = vp->vp_octets;
837 case PW_TYPE_IPV6ADDR:
838 case PW_TYPE_IPV6PREFIX:
839 case PW_TYPE_ABINARY:
840 /* nothing more to do */
844 len = 1; /* just in case */
845 array[0] = vp->vp_integer & 0xff;
850 len = 2; /* just in case */
851 array[0] = (vp->vp_integer >> 8) & 0xff;
852 array[1] = vp->vp_integer & 0xff;
856 case PW_TYPE_INTEGER:
857 len = 4; /* just in case */
858 lvalue = htonl(vp->vp_integer);
859 memcpy(array, &lvalue, sizeof(lvalue));
864 data = (const uint8_t *) &vp->vp_ipaddr;
865 len = 4; /* just in case */
869 * There are no tagged date attributes.
872 lvalue = htonl(vp->vp_date);
873 data = (const uint8_t *) &lvalue;
874 len = 4; /* just in case */
881 len = 4; /* just in case */
882 slvalue = htonl(vp->vp_signed);
883 memcpy(array, &slvalue, sizeof(slvalue));
890 fr_strerror_printf("ERROR: Cannot encode NULL TLV");
896 default: /* unknown type: ignore it */
897 fr_strerror_printf("ERROR: Unknown attribute type %d", vp->type);
902 * Bound the data to the calling size
904 if (len > (ssize_t) room) len = room;
907 * Encrypt the various password styles
909 * Attributes with encrypted values MUST be less than
912 switch (vp->flags.encrypt) {
913 case FLAG_ENCRYPT_USER_PASSWORD:
914 make_passwd(ptr, &len, data, len,
915 secret, packet->vector);
918 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
920 if (vp->flags.has_tag) lvalue = 1;
923 * Check if there's enough room. If there isn't,
924 * we discard the attribute.
926 * This is ONLY a problem if we have multiple VSA's
927 * in one Vendor-Specific, though.
929 if (room < (18 + lvalue)) return 0;
931 switch (packet->code) {
932 case PW_AUTHENTICATION_ACK:
933 case PW_AUTHENTICATION_REJECT:
934 case PW_ACCESS_CHALLENGE:
937 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->name);
941 if (lvalue) ptr[0] = vp->flags.tag;
942 make_tunnel_passwd(ptr + lvalue, &len, data, len,
944 secret, original->vector);
946 case PW_ACCOUNTING_REQUEST:
947 case PW_DISCONNECT_REQUEST:
949 ptr[0] = vp->flags.tag;
950 make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
951 secret, packet->vector);
957 * The code above ensures that this attribute
960 case FLAG_ENCRYPT_ASCEND_SECRET:
961 make_secret(ptr, packet->vector, secret, data);
962 len = AUTH_VECTOR_LEN;
967 if (vp->flags.has_tag && TAG_VALID(vp->flags.tag)) {
968 if (vp->type == PW_TYPE_STRING) {
969 if (len > ((ssize_t) (room - 1))) len = room - 1;
970 ptr[0] = vp->flags.tag;
972 } else if (vp->type == PW_TYPE_INTEGER) {
973 array[0] = vp->flags.tag;
974 } /* else it can't be any other type */
976 memcpy(ptr, data, len);
978 } /* switch over encryption flags */
981 return len + (ptr - start);;
984 static ssize_t attr_shift(const uint8_t *start, const uint8_t *end,
985 uint8_t *ptr, int hdr_len, ssize_t len,
986 int flag_offset, int vsa_offset)
988 int check_len = len - ptr[1];
989 int total = len + hdr_len;
992 * Pass 1: Check if the addition of the headers
993 * overflows the available room. If so, return
994 * what we were capable of encoding.
997 while (check_len > (255 - hdr_len)) {
999 check_len -= (255 - hdr_len);
1003 * Note that this results in a number of attributes maybe
1004 * being marked as "encoded", but which aren't in the
1005 * packet. Oh well. The solution is to fix the
1006 * "vp2data_any" function to take into account the header
1009 if ((ptr + ptr[1] + total) > end) {
1010 return (ptr + ptr[1]) - start;
1014 * Pass 2: Now that we know there's enough room,
1015 * re-arrange the data to form a set of valid
1016 * RADIUS attributes.
1019 int sublen = 255 - ptr[1];
1021 if (len <= sublen) {
1026 memmove(ptr + 255 + hdr_len, ptr + 255, sublen);
1027 memcpy(ptr + 255, ptr, hdr_len);
1029 if (vsa_offset) ptr[vsa_offset] += sublen;
1030 ptr[flag_offset] |= 0x80;
1034 if (vsa_offset) ptr[vsa_offset] = 3;
1038 if (vsa_offset) ptr[vsa_offset] += len;
1040 return (ptr + ptr[1]) - start;
1045 * Encode an "extended" attribute.
1047 int rad_vp2extended(const RADIUS_PACKET *packet,
1048 const RADIUS_PACKET *original,
1049 const char *secret, const VALUE_PAIR **pvp,
1050 uint8_t *ptr, size_t room)
1055 uint8_t *start = ptr;
1056 const VALUE_PAIR *vp = *pvp;
1058 VP_TRACE("rad_vp2extended %s\n", vp->name);
1059 if (vp->vendor < VENDORPEC_EXTENDED) {
1060 fr_strerror_printf("rad_vp2extended called for non-extended attribute");
1064 if (room < 3) return 0;
1066 ptr[0] = vp->attribute & 0xff;
1069 if (vp->flags.extended) {
1070 ptr[2] = (vp->attribute & 0xff00) >> 8;
1072 } else if (vp->flags.extended_flags) {
1073 if (room < 4) return 0;
1076 ptr[2] = (vp->attribute & 0xff00) >> 8;
1081 * Only "flagged" attributes can be longer than one
1084 if (!vp->flags.extended_flags && (room > 255)) {
1091 if (vp->flags.evs) {
1092 uint8_t *evs = ptr + ptr[1];
1094 if (room < (size_t) (ptr[1] + 5)) return 0;
1097 * RADIUS Attribute Type is packed into the high byte
1098 * of the Vendor Id. So over-write it in the packet.
1100 * And hard-code Extended-Type to Vendor-Specific.
1102 ptr[0] = (vp->vendor >> 24) & 0xff;
1105 evs[0] = 0; /* always zero */
1106 evs[1] = (vp->vendor >> 16) & 0xff;
1107 evs[2] = (vp->vendor >> 8) & 0xff;
1108 evs[3] = vp->vendor & 0xff;
1109 evs[4] = vp->attribute & 0xff;
1116 len = vp2data_any(packet, original, secret, nest,
1117 pvp, ptr + ptr[1], room - hdr_len);
1118 if (len < 0) return len;
1121 * There may be more than 252 octets of data encoded in
1122 * the attribute. If so, move the data up in the packet,
1123 * and copy the existing header over. Set the "M" flag ONLY
1124 * after copying the rest of the data.
1126 if (vp->flags.extended_flags && (len > (255 - ptr[1]))) {
1127 return attr_shift(start, start + room, ptr, 4, len, 3, 0);
1132 return (ptr + ptr[1]) - start;
1137 * Encode a WiMAX attribute.
1139 int rad_vp2wimax(const RADIUS_PACKET *packet,
1140 const RADIUS_PACKET *original,
1141 const char *secret, const VALUE_PAIR **pvp,
1142 uint8_t *ptr, size_t room)
1147 uint8_t *start = ptr;
1148 const VALUE_PAIR *vp = *pvp;
1151 * Double-check for WiMAX format.
1153 if (!vp->flags.wimax) {
1154 fr_strerror_printf("rad_vp2wimax called for non-WIMAX VSA");
1159 * Not enough room for:
1160 * attr, len, vendor-id, vsa, vsalen, continuation
1162 if (room < 9) return 0;
1165 * Build the Vendor-Specific header
1168 ptr[0] = PW_VENDOR_SPECIFIC;
1170 lvalue = htonl(vp->vendor);
1171 memcpy(ptr + 2, &lvalue, 4);
1172 ptr[6] = (vp->attribute & fr_attr_mask[1]);
1174 ptr[8] = 0; /* continuation byte */
1178 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1],
1180 if (len <= 0) return len;
1183 * There may be more than 252 octets of data encoded in
1184 * the attribute. If so, move the data up in the packet,
1185 * and copy the existing header over. Set the "C" flag
1186 * ONLY after copying the rest of the data.
1188 if (len > (255 - ptr[1])) {
1189 return attr_shift(start, start + room, ptr, hdr_len, len, 8, 7);
1196 if ((fr_debug_flag > 3) && fr_log_fp) {
1199 da = dict_attrbyvalue(ptr[6], vp->vendor);
1200 if (da && (da->type == PW_TYPE_TLV)) {
1201 fprintf(fr_log_fp, "\t%s = ...\n", da->name);
1204 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) %02x %02x %02x ",
1206 ptr[2], ptr[3], ptr[4], ptr[5],
1207 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5],
1208 ptr[6], ptr[7], ptr[8]);
1209 print_hex_data(ptr + 9, len, 3);
1213 return (ptr + ptr[1]) - start;
1217 * Encode an RFC format TLV. This could be a standard attribute,
1218 * or a TLV data type. If it's a standard attribute, then
1219 * vp->attribute == attribute. Otherwise, attribute may be
1222 static ssize_t vp2attr_rfc(const RADIUS_PACKET *packet,
1223 const RADIUS_PACKET *original,
1224 const char *secret, const VALUE_PAIR **pvp,
1225 unsigned int attribute, uint8_t *ptr, size_t room)
1229 if (room < 2) return 0;
1231 ptr[0] = attribute & 0xff;
1234 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1236 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1], room);
1237 if (len < 0) return len;
1242 if ((fr_debug_flag > 3) && fr_log_fp) {
1243 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1244 print_hex_data(ptr + 2, len, 3);
1253 * Encode a VSA which is a TLV. If it's in the RFC format, call
1254 * vp2attr_rfc. Otherwise, encode it here.
1256 static ssize_t vp2attr_vsa(const RADIUS_PACKET *packet,
1257 const RADIUS_PACKET *original,
1258 const char *secret, const VALUE_PAIR **pvp,
1259 unsigned int attribute, unsigned int vendor,
1260 uint8_t *ptr, size_t room)
1264 const VALUE_PAIR *vp = *pvp;
1267 * Unknown vendor: RFC format.
1268 * Known vendor and RFC format: go do that.
1270 VP_TRACE("Encoding VSA %u.%u\n", vendor, attribute);
1271 dv = dict_vendorbyvalue(vendor);
1272 VP_TRACE("Flags %d %d\n", vp->flags.is_tlv, vp->flags.has_tlv);
1274 (!vp->flags.is_tlv && (dv->type == 1) && (dv->length == 1))) {
1275 VP_TRACE("Encoding RFC %u.%u\n", vendor, attribute);
1276 return vp2attr_rfc(packet, original, secret, pvp,
1277 attribute, ptr, room);
1282 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1283 " type %u", (unsigned) dv->type);
1287 ptr[0] = 0; /* attr must be 24-bit */
1288 ptr[1] = (attribute >> 16) & 0xff;
1289 ptr[2] = (attribute >> 8) & 0xff;
1290 ptr[3] = attribute & 0xff;
1292 if ((fr_debug_flag > 3) && fr_log_fp) fprintf(fr_log_fp, "\t\t%02x%02x%02x%02x ",
1293 ptr[0], ptr[1], ptr[2], ptr[3]);
1298 ptr[0] = (attribute >> 8) & 0xff;
1299 ptr[1] = attribute & 0xff;
1301 if ((fr_debug_flag > 3) && fr_log_fp) fprintf(fr_log_fp, "\t\t%02x%02x ", ptr[0], ptr[1]);
1306 ptr[0] = attribute & 0xff;
1308 if ((fr_debug_flag > 3) && fr_log_fp) fprintf(fr_log_fp, "\t\t%02x ", ptr[0]);
1313 switch (dv->length) {
1315 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1316 " length %u", (unsigned) dv->length);
1324 ptr[dv->type + 1] = dv->type + 2;
1326 if ((fr_debug_flag > 3) && fr_log_fp) fprintf(fr_log_fp, "%02x%02x ",
1333 ptr[dv->type] = dv->type;
1335 if ((fr_debug_flag > 3) && fr_log_fp) fprintf(fr_log_fp, "%02x ", ptr[dv->type]);
1341 if (room > ((unsigned) 255 - (dv->type + dv->length))) {
1342 room = 255 - (dv->type + dv->length);
1345 len = vp2data_any(packet, original, secret, 0, pvp,
1346 ptr + dv->type + dv->length, room);
1347 if (len < 0) return len;
1349 if (dv->length) ptr[dv->type + dv->length - 1] += len;
1352 if ((fr_debug_flag > 3) && fr_log_fp) {
1353 print_hex_data(ptr + dv->type + dv->length, len, 3);
1357 return dv->type + dv->length + len;
1362 * Encode a Vendor-Specific attribute.
1364 int rad_vp2vsa(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1365 const char *secret, const VALUE_PAIR **pvp, uint8_t *ptr,
1370 const VALUE_PAIR *vp = *pvp;
1373 * Double-check for WiMAX format.
1375 if (vp->flags.wimax) {
1376 return rad_vp2wimax(packet, original, secret, pvp,
1380 if (vp->vendor > FR_MAX_VENDOR) {
1381 fr_strerror_printf("rad_vp2vsa: Invalid arguments");
1386 * Not enough room for:
1387 * attr, len, vendor-id
1389 if (room < 6) return 0;
1392 * Build the Vendor-Specific header
1394 ptr[0] = PW_VENDOR_SPECIFIC;
1396 lvalue = htonl(vp->vendor);
1397 memcpy(ptr + 2, &lvalue, 4);
1399 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1401 len = vp2attr_vsa(packet, original, secret, pvp,
1402 vp->attribute, vp->vendor,
1403 ptr + ptr[1], room);
1404 if (len < 0) return len;
1407 if ((fr_debug_flag > 3) && fr_log_fp) {
1408 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) ",
1410 ptr[2], ptr[3], ptr[4], ptr[5],
1411 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5]);
1412 print_hex_data(ptr + 6, len, 3);
1423 * Encode an RFC standard attribute 1..255
1425 int rad_vp2rfc(const RADIUS_PACKET *packet,
1426 const RADIUS_PACKET *original,
1427 const char *secret, const VALUE_PAIR **pvp,
1428 uint8_t *ptr, size_t room)
1430 const VALUE_PAIR *vp = *pvp;
1432 if (vp->vendor != 0) {
1433 fr_strerror_printf("rad_vp2rfc called with VSA");
1437 if ((vp->attribute == 0) || (vp->attribute > 255)) {
1438 fr_strerror_printf("rad_vp2rfc called with non-standard attribute %u", vp->attribute);
1442 if ((vp->length == 0) &&
1443 (vp->attribute != PW_CHARGEABLE_USER_IDENTITY)) {
1447 return vp2attr_rfc(packet, original, secret, pvp, vp->attribute,
1453 * Parse a data structure into a RADIUS attribute.
1455 int rad_vp2attr(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1456 const char *secret, const VALUE_PAIR **pvp, uint8_t *start,
1459 const VALUE_PAIR *vp;
1461 if (!pvp || !*pvp || !start || (room <= 2)) return -1;
1466 * RFC format attributes take the fast path.
1468 if (vp->vendor == 0) {
1469 if (vp->attribute > 255) return 0;
1472 * Message-Authenticator is hard-coded.
1474 if (vp->attribute == PW_MESSAGE_AUTHENTICATOR) {
1475 if (room < 18) return -1;
1477 start[0] = PW_MESSAGE_AUTHENTICATOR;
1479 memset(start + 2, 0, 16);
1481 if ((fr_debug_flag > 3) && fr_log_fp) {
1482 fprintf(fr_log_fp, "\t\t50 12 ...\n");
1486 *pvp = (*pvp)->next;
1490 return rad_vp2rfc(packet, original, secret, pvp,
1494 if (vp->vendor > FR_MAX_VENDOR) {
1495 return rad_vp2extended(packet, original, secret, pvp,
1499 if (vp->flags.wimax) {
1500 return rad_vp2wimax(packet, original, secret, pvp,
1504 return rad_vp2vsa(packet, original, secret, pvp,
1512 int rad_encode(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1515 radius_packet_t *hdr;
1517 uint16_t total_length;
1519 const VALUE_PAIR *reply;
1521 char ip_buffer[128];
1524 * A 4K packet, aligned on 64-bits.
1526 uint64_t data[MAX_PACKET_LEN / sizeof(uint64_t)];
1528 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1529 what = fr_packet_codes[packet->code];
1534 DEBUG("Sending %s of id %d to %s port %d\n",
1536 inet_ntop(packet->dst_ipaddr.af,
1537 &packet->dst_ipaddr.ipaddr,
1538 ip_buffer, sizeof(ip_buffer)),
1542 * Double-check some things based on packet code.
1544 switch (packet->code) {
1545 case PW_AUTHENTICATION_ACK:
1546 case PW_AUTHENTICATION_REJECT:
1547 case PW_ACCESS_CHALLENGE:
1549 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1555 * These packet vectors start off as all zero.
1557 case PW_ACCOUNTING_REQUEST:
1558 case PW_DISCONNECT_REQUEST:
1559 case PW_COA_REQUEST:
1560 memset(packet->vector, 0, sizeof(packet->vector));
1568 * Use memory on the stack, until we know how
1569 * large the packet will be.
1571 hdr = (radius_packet_t *) data;
1574 * Build standard header
1576 hdr->code = packet->code;
1577 hdr->id = packet->id;
1579 memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1581 total_length = AUTH_HDR_LEN;
1584 * Load up the configuration values for the user
1590 * FIXME: Loop twice over the reply list. The first time,
1591 * calculate the total length of data. The second time,
1592 * allocate the memory, and fill in the VP's.
1594 * Hmm... this may be slower than just doing a small
1599 * Loop over the reply attributes for the packet.
1601 reply = packet->vps;
1604 * Ignore non-wire attributes, but allow extended
1607 if ((reply->vendor == 0) &&
1608 ((reply->attribute & 0xFFFF) >= 256) &&
1609 !reply->flags.extended && !reply->flags.extended_flags) {
1612 * Permit the admin to send BADLY formatted
1613 * attributes with a debug build.
1615 if (reply->attribute == PW_RAW_ATTRIBUTE) {
1616 memcpy(ptr, reply->vp_octets, reply->length);
1617 len = reply->length;
1618 reply = reply->next;
1622 reply = reply->next;
1627 * Set the Message-Authenticator to the correct
1628 * length and initial value.
1630 if (reply->attribute == PW_MESSAGE_AUTHENTICATOR) {
1632 * Cache the offset to the
1633 * Message-Authenticator
1635 packet->offset = total_length;
1639 * Print out ONLY the attributes which
1640 * we're sending over the wire, and print
1641 * them out BEFORE they're encrypted.
1645 len = rad_vp2attr(packet, original, secret, &reply, ptr,
1646 ((uint8_t *) data) + sizeof(data) - ptr);
1647 if (len < 0) return -1;
1650 * Failed to encode the attribute, likely because
1651 * the packet is full.
1654 (total_length > (sizeof(data) - 2 - reply->length))) {
1655 DEBUG("WARNING: Attributes are too long for packet. Discarding data past %d bytes", total_length);
1660 next: /* Used only for Raw-Attribute */
1663 total_length += len;
1664 } /* done looping over all attributes */
1667 * Fill in the rest of the fields, and copy the data over
1668 * from the local stack to the newly allocated memory.
1670 * Yes, all this 'memcpy' is slow, but it means
1671 * that we only allocate the minimum amount of
1672 * memory for a request.
1674 packet->data_len = total_length;
1675 packet->data = (uint8_t *) malloc(packet->data_len);
1676 if (!packet->data) {
1677 fr_strerror_printf("Out of memory");
1681 memcpy(packet->data, hdr, packet->data_len);
1682 hdr = (radius_packet_t *) packet->data;
1684 total_length = htons(total_length);
1685 memcpy(hdr->length, &total_length, sizeof(total_length));
1692 * Sign a previously encoded packet.
1694 int rad_sign(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1697 radius_packet_t *hdr = (radius_packet_t *)packet->data;
1700 * It wasn't assigned an Id, this is bad!
1702 if (packet->id < 0) {
1703 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1707 if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1708 (packet->offset < 0)) {
1709 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1714 * If there's a Message-Authenticator, update it
1715 * now, BEFORE updating the authentication vector.
1717 if (packet->offset > 0) {
1718 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1720 switch (packet->code) {
1721 case PW_ACCOUNTING_REQUEST:
1722 case PW_ACCOUNTING_RESPONSE:
1723 case PW_DISCONNECT_REQUEST:
1724 case PW_DISCONNECT_ACK:
1725 case PW_DISCONNECT_NAK:
1726 case PW_COA_REQUEST:
1729 memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1732 case PW_AUTHENTICATION_ACK:
1733 case PW_AUTHENTICATION_REJECT:
1734 case PW_ACCESS_CHALLENGE:
1736 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1739 memcpy(hdr->vector, original->vector,
1743 default: /* others have vector already set to zero */
1749 * Set the authentication vector to zero,
1750 * calculate the signature, and put it
1751 * into the Message-Authenticator
1754 fr_hmac_md5(packet->data, packet->data_len,
1755 (const uint8_t *) secret, strlen(secret),
1757 memcpy(packet->data + packet->offset + 2,
1758 calc_auth_vector, AUTH_VECTOR_LEN);
1761 * Copy the original request vector back
1762 * to the raw packet.
1764 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1768 * Switch over the packet code, deciding how to
1771 switch (packet->code) {
1773 * Request packets are not signed, bur
1774 * have a random authentication vector.
1776 case PW_AUTHENTICATION_REQUEST:
1777 case PW_STATUS_SERVER:
1781 * Reply packets are signed with the
1782 * authentication vector of the request.
1789 fr_MD5Init(&context);
1790 fr_MD5Update(&context, packet->data, packet->data_len);
1791 fr_MD5Update(&context, (const uint8_t *) secret,
1793 fr_MD5Final(digest, &context);
1795 memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1796 memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1799 }/* switch over packet codes */
1805 * Reply to the request. Also attach
1806 * reply attribute value pairs and any user message provided.
1808 int rad_send(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1813 char ip_buffer[128];
1816 * Maybe it's a fake packet. Don't send it.
1818 if (!packet || (packet->sockfd < 0)) {
1822 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1823 what = fr_packet_codes[packet->code];
1829 * First time through, allocate room for the packet
1831 if (!packet->data) {
1833 * Encode the packet.
1835 if (rad_encode(packet, original, secret) < 0) {
1840 * Re-sign it, including updating the
1841 * Message-Authenticator.
1843 if (rad_sign(packet, original, secret) < 0) {
1848 * If packet->data points to data, then we print out
1849 * the VP list again only for debugging.
1851 } else if (fr_debug_flag) {
1852 DEBUG("Sending %s of id %d to %s port %d\n", what, packet->id,
1853 inet_ntop(packet->dst_ipaddr.af,
1854 &packet->dst_ipaddr.ipaddr,
1855 ip_buffer, sizeof(ip_buffer)),
1858 for (reply = packet->vps; reply; reply = reply->next) {
1859 if ((reply->vendor == 0) &&
1860 ((reply->attribute & 0xFFFF) > 0xff)) continue;
1866 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
1870 * And send it on it's way.
1872 return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
1873 &packet->src_ipaddr, packet->src_port,
1874 &packet->dst_ipaddr, packet->dst_port);
1878 * Do a comparison of two authentication digests by comparing
1879 * the FULL digest. Otehrwise, the server can be subject to
1880 * timing attacks that allow attackers find a valid message
1883 * http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
1885 int rad_digest_cmp(const uint8_t *a, const uint8_t *b, size_t length)
1890 for (i = 0; i < length; i++) {
1891 result |= a[i] ^ b[i];
1894 return result; /* 0 is OK, !0 is !OK, just like memcmp */
1899 * Validates the requesting client NAS. Calculates the
1900 * signature based on the clients private key.
1902 static int calc_acctdigest(RADIUS_PACKET *packet, const char *secret)
1904 uint8_t digest[AUTH_VECTOR_LEN];
1908 * Zero out the auth_vector in the received packet.
1909 * Then append the shared secret to the received packet,
1910 * and calculate the MD5 sum. This must be the same
1911 * as the original MD5 sum (packet->vector).
1913 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1916 * MD5(packet + secret);
1918 fr_MD5Init(&context);
1919 fr_MD5Update(&context, packet->data, packet->data_len);
1920 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1921 fr_MD5Final(digest, &context);
1924 * Return 0 if OK, 2 if not OK.
1926 if (rad_digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
1932 * Validates the requesting client NAS. Calculates the
1933 * signature based on the clients private key.
1935 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1938 uint8_t calc_digest[AUTH_VECTOR_LEN];
1944 if (original == NULL) {
1949 * Copy the original vector in place.
1951 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
1954 * MD5(packet + secret);
1956 fr_MD5Init(&context);
1957 fr_MD5Update(&context, packet->data, packet->data_len);
1958 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1959 fr_MD5Final(calc_digest, &context);
1962 * Copy the packet's vector back to the packet.
1964 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
1967 * Return 0 if OK, 2 if not OK.
1969 if (rad_digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
1975 * Check if a set of RADIUS formatted TLVs are OK.
1977 int rad_tlv_ok(const uint8_t *data, size_t length,
1978 size_t dv_type, size_t dv_length)
1980 const uint8_t *end = data + length;
1982 if ((dv_length > 2) || (dv_type == 0) || (dv_type > 4)) {
1983 fr_strerror_printf("rad_tlv_ok: Invalid arguments");
1987 while (data < end) {
1990 if ((data + dv_type + dv_length) > end) {
1991 fr_strerror_printf("Attribute header overflow");
1997 if ((data[0] == 0) && (data[1] == 0) &&
1998 (data[2] == 0) && (data[3] == 0)) {
2000 fr_strerror_printf("Invalid attribute 0");
2005 fr_strerror_printf("Invalid attribute > 2^24");
2011 if ((data[1] == 0) && (data[1] == 0)) goto zero;
2015 if (data[0] == 0) goto zero;
2019 fr_strerror_printf("Internal sanity check failed");
2023 switch (dv_length) {
2028 if (data[dv_type + 1] != 0) {
2029 fr_strerror_printf("Attribute is longer than 256 octets");
2034 attrlen = data[dv_type + dv_length - 1];
2039 fr_strerror_printf("Internal sanity check failed");
2043 if (attrlen < (dv_type + dv_length)) {
2044 fr_strerror_printf("Attribute header has invalid length");
2048 if (attrlen > length) {
2049 fr_strerror_printf("Attribute overflows container");
2062 * See if the data pointed to by PTR is a valid RADIUS packet.
2064 * packet is not 'const * const' because we may update data_len,
2065 * if there's more data in the UDP packet than in the RADIUS packet.
2067 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
2072 radius_packet_t *hdr;
2073 char host_ipaddr[128];
2079 * Check for packets smaller than the packet header.
2081 * RFC 2865, Section 3., subsection 'length' says:
2083 * "The minimum length is 20 ..."
2085 if (packet->data_len < AUTH_HDR_LEN) {
2086 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %d < minimum %d)",
2087 inet_ntop(packet->src_ipaddr.af,
2088 &packet->src_ipaddr.ipaddr,
2089 host_ipaddr, sizeof(host_ipaddr)),
2090 (int) packet->data_len, AUTH_HDR_LEN);
2095 * RFC 2865, Section 3., subsection 'length' says:
2097 * " ... and maximum length is 4096."
2099 if (packet->data_len > MAX_PACKET_LEN) {
2100 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (received %d > maximum %d)",
2101 inet_ntop(packet->src_ipaddr.af,
2102 &packet->src_ipaddr.ipaddr,
2103 host_ipaddr, sizeof(host_ipaddr)),
2104 (int) packet->data_len, MAX_PACKET_LEN);
2109 * Check for packets with mismatched size.
2110 * i.e. We've received 128 bytes, and the packet header
2111 * says it's 256 bytes long.
2113 totallen = (packet->data[2] << 8) | packet->data[3];
2114 hdr = (radius_packet_t *)packet->data;
2117 * Code of 0 is not understood.
2118 * Code of 16 or greate is not understood.
2120 if ((hdr->code == 0) ||
2121 (hdr->code >= FR_MAX_PACKET_CODE)) {
2122 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code%d ",
2123 inet_ntop(packet->src_ipaddr.af,
2124 &packet->src_ipaddr.ipaddr,
2125 host_ipaddr, sizeof(host_ipaddr)),
2131 * Message-Authenticator is required in Status-Server
2132 * packets, otherwise they can be trivially forged.
2134 if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
2137 * It's also required if the caller asks for it.
2139 if (flags) require_ma = 1;
2142 * Repeat the length checks. This time, instead of
2143 * looking at the data we received, look at the value
2144 * of the 'length' field inside of the packet.
2146 * Check for packets smaller than the packet header.
2148 * RFC 2865, Section 3., subsection 'length' says:
2150 * "The minimum length is 20 ..."
2152 if (totallen < AUTH_HDR_LEN) {
2153 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %d < minimum %d)",
2154 inet_ntop(packet->src_ipaddr.af,
2155 &packet->src_ipaddr.ipaddr,
2156 host_ipaddr, sizeof(host_ipaddr)),
2157 totallen, AUTH_HDR_LEN);
2162 * And again, for the value of the 'length' field.
2164 * RFC 2865, Section 3., subsection 'length' says:
2166 * " ... and maximum length is 4096."
2168 if (totallen > MAX_PACKET_LEN) {
2169 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (length %d > maximum %d)",
2170 inet_ntop(packet->src_ipaddr.af,
2171 &packet->src_ipaddr.ipaddr,
2172 host_ipaddr, sizeof(host_ipaddr)),
2173 totallen, MAX_PACKET_LEN);
2178 * RFC 2865, Section 3., subsection 'length' says:
2180 * "If the packet is shorter than the Length field
2181 * indicates, it MUST be silently discarded."
2183 * i.e. No response to the NAS.
2185 if (packet->data_len < totallen) {
2186 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %d octets, packet length says %d",
2187 inet_ntop(packet->src_ipaddr.af,
2188 &packet->src_ipaddr.ipaddr,
2189 host_ipaddr, sizeof(host_ipaddr)),
2190 (int) packet->data_len, totallen);
2195 * RFC 2865, Section 3., subsection 'length' says:
2197 * "Octets outside the range of the Length field MUST be
2198 * treated as padding and ignored on reception."
2200 if (packet->data_len > totallen) {
2202 * We're shortening the packet below, but just
2203 * to be paranoid, zero out the extra data.
2205 memset(packet->data + totallen, 0, packet->data_len - totallen);
2206 packet->data_len = totallen;
2210 * Walk through the packet's attributes, ensuring that
2211 * they add up EXACTLY to the size of the packet.
2213 * If they don't, then the attributes either under-fill
2214 * or over-fill the packet. Any parsing of the packet
2215 * is impossible, and will result in unknown side effects.
2217 * This would ONLY happen with buggy RADIUS implementations,
2218 * or with an intentional attack. Either way, we do NOT want
2219 * to be vulnerable to this problem.
2222 count = totallen - AUTH_HDR_LEN;
2227 * We need at least 2 bytes to check the
2231 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute header overflows the packet",
2232 inet_ntop(packet->src_ipaddr.af,
2233 &packet->src_ipaddr.ipaddr,
2234 host_ipaddr, sizeof(host_ipaddr)));
2239 * Attribute number zero is NOT defined.
2242 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
2243 inet_ntop(packet->src_ipaddr.af,
2244 &packet->src_ipaddr.ipaddr,
2245 host_ipaddr, sizeof(host_ipaddr)));
2250 * Attributes are at LEAST as long as the ID & length
2251 * fields. Anything shorter is an invalid attribute.
2254 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u too short",
2255 inet_ntop(packet->src_ipaddr.af,
2256 &packet->src_ipaddr.ipaddr,
2257 host_ipaddr, sizeof(host_ipaddr)),
2263 * If there are fewer bytes in the packet than in the
2264 * attribute, it's a bad packet.
2266 if (count < attr[1]) {
2267 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u data overflows the packet",
2268 inet_ntop(packet->src_ipaddr.af,
2269 &packet->src_ipaddr.ipaddr,
2270 host_ipaddr, sizeof(host_ipaddr)),
2276 * Sanity check the attributes for length.
2279 default: /* don't do anything by default */
2283 * If there's an EAP-Message, we require
2284 * a Message-Authenticator.
2286 case PW_EAP_MESSAGE:
2290 case PW_MESSAGE_AUTHENTICATOR:
2291 if (attr[1] != 2 + AUTH_VECTOR_LEN) {
2292 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
2293 inet_ntop(packet->src_ipaddr.af,
2294 &packet->src_ipaddr.ipaddr,
2295 host_ipaddr, sizeof(host_ipaddr)),
2304 * FIXME: Look up the base 255 attributes in the
2305 * dictionary, and switch over their type. For
2306 * integer/date/ip, the attribute length SHOULD
2309 count -= attr[1]; /* grab the attribute length */
2311 num_attributes++; /* seen one more attribute */
2315 * If the attributes add up to a packet, it's allowed.
2317 * If not, we complain, and throw the packet away.
2320 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
2321 inet_ntop(packet->src_ipaddr.af,
2322 &packet->src_ipaddr.ipaddr,
2323 host_ipaddr, sizeof(host_ipaddr)));
2328 * If we're configured to look for a maximum number of
2329 * attributes, and we've seen more than that maximum,
2330 * then throw the packet away, as a possible DoS.
2332 if ((fr_max_attributes > 0) &&
2333 (num_attributes > fr_max_attributes)) {
2334 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2335 inet_ntop(packet->src_ipaddr.af,
2336 &packet->src_ipaddr.ipaddr,
2337 host_ipaddr, sizeof(host_ipaddr)),
2338 num_attributes, fr_max_attributes);
2343 * http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
2345 * A packet with an EAP-Message attribute MUST also have
2346 * a Message-Authenticator attribute.
2348 * A Message-Authenticator all by itself is OK, though.
2350 * Similarly, Status-Server packets MUST contain
2351 * Message-Authenticator attributes.
2353 if (require_ma && ! seen_ma) {
2354 fr_strerror_printf("WARNING: Insecure packet from host %s: Packet does not contain required Message-Authenticator attribute",
2355 inet_ntop(packet->src_ipaddr.af,
2356 &packet->src_ipaddr.ipaddr,
2357 host_ipaddr, sizeof(host_ipaddr)));
2362 * Fill RADIUS header fields
2364 packet->code = hdr->code;
2365 packet->id = hdr->id;
2366 memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
2373 * Receive UDP client requests, and fill in
2374 * the basics of a RADIUS_PACKET structure.
2376 RADIUS_PACKET *rad_recv(int fd, int flags)
2379 RADIUS_PACKET *packet;
2382 * Allocate the new request data structure
2384 if ((packet = malloc(sizeof(*packet))) == NULL) {
2385 fr_strerror_printf("out of memory");
2388 memset(packet, 0, sizeof(*packet));
2391 sock_flags = MSG_PEEK;
2395 packet->data_len = rad_recvfrom(fd, &packet->data, sock_flags,
2396 &packet->src_ipaddr, &packet->src_port,
2397 &packet->dst_ipaddr, &packet->dst_port);
2400 * Check for socket errors.
2402 if (packet->data_len < 0) {
2403 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
2404 /* packet->data is NULL */
2410 * If the packet is too big, then rad_recvfrom did NOT
2411 * allocate memory. Instead, it just discarded the
2414 if (packet->data_len > MAX_PACKET_LEN) {
2415 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
2416 /* packet->data is NULL */
2422 * Read no data. Continue.
2423 * This check is AFTER the MAX_PACKET_LEN check above, because
2424 * if the packet is larger than MAX_PACKET_LEN, we also have
2425 * packet->data == NULL
2427 if ((packet->data_len == 0) || !packet->data) {
2428 fr_strerror_printf("Empty packet: Socket is not ready.");
2434 * See if it's a well-formed RADIUS packet.
2436 if (!rad_packet_ok(packet, flags)) {
2442 * Remember which socket we read the packet from.
2444 packet->sockfd = fd;
2447 * FIXME: Do even more filtering by only permitting
2448 * certain IP's. The problem is that we don't know
2449 * how to do this properly for all possible clients...
2453 * Explicitely set the VP list to empty.
2457 if (fr_debug_flag) {
2458 char host_ipaddr[128];
2460 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2461 DEBUG("rad_recv: %s packet from host %s port %d",
2462 fr_packet_codes[packet->code],
2463 inet_ntop(packet->src_ipaddr.af,
2464 &packet->src_ipaddr.ipaddr,
2465 host_ipaddr, sizeof(host_ipaddr)),
2468 DEBUG("rad_recv: Packet from host %s port %d code=%d",
2469 inet_ntop(packet->src_ipaddr.af,
2470 &packet->src_ipaddr.ipaddr,
2471 host_ipaddr, sizeof(host_ipaddr)),
2475 DEBUG(", id=%d, length=%d\n",
2476 packet->id, (int) packet->data_len);
2480 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2488 * Verify the signature of a packet.
2490 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2497 if (!packet || !packet->data) return -1;
2500 * Before we allocate memory for the attributes, do more
2503 ptr = packet->data + AUTH_HDR_LEN;
2504 length = packet->data_len - AUTH_HDR_LEN;
2505 while (length > 0) {
2506 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
2507 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
2512 default: /* don't do anything. */
2516 * Note that more than one Message-Authenticator
2517 * attribute is invalid.
2519 case PW_MESSAGE_AUTHENTICATOR:
2520 memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
2521 memset(&ptr[2], 0, AUTH_VECTOR_LEN);
2523 switch (packet->code) {
2527 case PW_ACCOUNTING_REQUEST:
2528 case PW_ACCOUNTING_RESPONSE:
2529 case PW_DISCONNECT_REQUEST:
2530 case PW_DISCONNECT_ACK:
2531 case PW_DISCONNECT_NAK:
2532 case PW_COA_REQUEST:
2535 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2538 case PW_AUTHENTICATION_ACK:
2539 case PW_AUTHENTICATION_REJECT:
2540 case PW_ACCESS_CHALLENGE:
2542 fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2545 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2549 fr_hmac_md5(packet->data, packet->data_len,
2550 (const uint8_t *) secret, strlen(secret),
2552 if (rad_digest_cmp(calc_auth_vector, msg_auth_vector,
2553 sizeof(calc_auth_vector)) != 0) {
2555 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator! (Shared secret is incorrect.)",
2556 inet_ntop(packet->src_ipaddr.af,
2557 &packet->src_ipaddr.ipaddr,
2558 buffer, sizeof(buffer)));
2559 /* Silently drop packet, according to RFC 3579 */
2561 } /* else the message authenticator was good */
2564 * Reinitialize Authenticators.
2566 memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2567 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2569 } /* switch over the attributes */
2573 } /* loop over the packet, sanity checking the attributes */
2576 * It looks like a RADIUS packet, but we can't validate
2579 if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2581 fr_strerror_printf("Received Unknown packet code %d "
2582 "from client %s port %d: Cannot validate signature.",
2584 inet_ntop(packet->src_ipaddr.af,
2585 &packet->src_ipaddr.ipaddr,
2586 buffer, sizeof(buffer)),
2592 * Calculate and/or verify digest.
2594 switch(packet->code) {
2598 case PW_AUTHENTICATION_REQUEST:
2599 case PW_STATUS_SERVER:
2601 * The authentication vector is random
2602 * nonsense, invented by the client.
2606 case PW_COA_REQUEST:
2607 case PW_DISCONNECT_REQUEST:
2608 case PW_ACCOUNTING_REQUEST:
2609 if (calc_acctdigest(packet, secret) > 1) {
2610 fr_strerror_printf("Received %s packet "
2611 "from client %s with invalid signature! (Shared secret is incorrect.)",
2612 fr_packet_codes[packet->code],
2613 inet_ntop(packet->src_ipaddr.af,
2614 &packet->src_ipaddr.ipaddr,
2615 buffer, sizeof(buffer)));
2620 /* Verify the reply digest */
2621 case PW_AUTHENTICATION_ACK:
2622 case PW_AUTHENTICATION_REJECT:
2623 case PW_ACCESS_CHALLENGE:
2624 case PW_ACCOUNTING_RESPONSE:
2625 case PW_DISCONNECT_ACK:
2626 case PW_DISCONNECT_NAK:
2629 rcode = calc_replydigest(packet, original, secret);
2631 fr_strerror_printf("Received %s packet "
2632 "from home server %s port %d with invalid signature! (Shared secret is incorrect.)",
2633 fr_packet_codes[packet->code],
2634 inet_ntop(packet->src_ipaddr.af,
2635 &packet->src_ipaddr.ipaddr,
2636 buffer, sizeof(buffer)),
2643 fr_strerror_printf("Received Unknown packet code %d "
2644 "from client %s port %d: Cannot validate signature",
2646 inet_ntop(packet->src_ipaddr.af,
2647 &packet->src_ipaddr.ipaddr,
2648 buffer, sizeof(buffer)),
2658 * Create a "raw" attribute from the attribute contents.
2660 static ssize_t data2vp_raw(UNUSED const RADIUS_PACKET *packet,
2661 UNUSED const RADIUS_PACKET *original,
2662 UNUSED const char *secret,
2663 unsigned int attribute, unsigned int vendor,
2664 const uint8_t *data, size_t length,
2670 * Keep the next function happy.
2672 vp = pairalloc(NULL);
2673 vp = paircreate_raw(attribute, vendor, PW_TYPE_OCTETS, vp);
2675 fr_strerror_printf("data2vp_raw: Failed creating attribute");
2679 vp->length = length;
2682 * If the data is too large, mark it as a "TLV".
2684 if (length <= sizeof(vp->vp_octets)) {
2685 memcpy(vp->vp_octets, data, length);
2687 vp->type = PW_TYPE_TLV;
2688 vp->vp_tlv = malloc(length);
2693 memcpy(vp->vp_tlv, data, length);
2702 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
2703 const RADIUS_PACKET *original,
2705 unsigned int attribute, unsigned int vendor,
2707 const uint8_t *start, size_t length,
2711 * Create any kind of VP from the attribute contents.
2713 * Will return -1 on error, or "length".
2715 static ssize_t data2vp_any(const RADIUS_PACKET *packet,
2716 const RADIUS_PACKET *original,
2717 const char *secret, int nest,
2718 unsigned int attribute, unsigned int vendor,
2719 const uint8_t *data, size_t length,
2722 int data_offset = 0;
2724 VALUE_PAIR *vp = NULL;
2728 * Hacks for CUI. The WiMAX spec says that it
2729 * can be zero length, even though this is
2730 * forbidden by the RADIUS specs. So... we make
2731 * a special case for it.
2733 if ((vendor == 0) &&
2734 (attribute == PW_CHARGEABLE_USER_IDENTITY)) {
2735 data = (const uint8_t *) "";
2743 da = dict_attrbyvalue(attribute, vendor);
2746 * Unknown attribute. Create it as a "raw" attribute.
2749 VP_TRACE("Not found %u.%u\n", vendor, attribute);
2751 if (vp) pairfree(&vp);
2752 return data2vp_raw(packet, original, secret,
2753 attribute, vendor, data, length, pvp);
2757 * TLVs are handled first. They can't be tagged, and
2758 * they can't be encrypted.
2760 if (da->type == PW_TYPE_TLV) {
2761 VP_TRACE("Found TLV %u.%u\n", vendor, attribute);
2762 return data2vp_tlvs(packet, original, secret,
2763 attribute, vendor, nest,
2768 * The attribute is known, and well formed. We can now
2769 * create it. The main failure from here on in is being
2778 if (vp->flags.has_tag) {
2779 if (TAG_VALID(data[0]) ||
2780 (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD)) {
2782 * Tunnel passwords REQUIRE a tag, even
2783 * if don't have a valid tag.
2785 vp->flags.tag = data[0];
2787 if ((vp->type == PW_TYPE_STRING) ||
2788 (vp->type == PW_TYPE_OCTETS)) {
2789 if (length == 0) goto raw;
2796 * Copy the data to be decrypted
2798 vp->length = length - data_offset;
2799 memcpy(&vp->vp_octets[0], data + data_offset, vp->length);
2802 * Decrypt the attribute.
2804 switch (vp->flags.encrypt) {
2808 case FLAG_ENCRYPT_USER_PASSWORD:
2810 rad_pwdecode(vp->vp_strvalue,
2814 rad_pwdecode(vp->vp_strvalue,
2818 if (vp->attribute == PW_USER_PASSWORD) {
2819 vp->length = strlen(vp->vp_strvalue);
2824 * Tunnel-Password's may go ONLY
2825 * in response packets.
2827 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
2828 if (!original) goto raw;
2830 if (rad_tunnel_pwdecode(vp->vp_octets, &vp->length,
2831 secret, original->vector) < 0) {
2837 * Ascend-Send-Secret
2838 * Ascend-Receive-Secret
2840 case FLAG_ENCRYPT_ASCEND_SECRET:
2844 uint8_t my_digest[AUTH_VECTOR_LEN];
2845 make_secret(my_digest,
2848 memcpy(vp->vp_strvalue, my_digest,
2850 vp->vp_strvalue[AUTH_VECTOR_LEN] = '\0';
2851 vp->length = strlen(vp->vp_strvalue);
2857 } /* switch over encryption flags */
2861 case PW_TYPE_STRING:
2862 case PW_TYPE_OCTETS:
2863 case PW_TYPE_ABINARY:
2864 /* nothing more to do */
2868 if (vp->length != 1) goto raw;
2870 vp->vp_integer = vp->vp_octets[0];
2875 if (vp->length != 2) goto raw;
2877 vp->vp_integer = (vp->vp_octets[0] << 8) | vp->vp_octets[1];
2880 case PW_TYPE_INTEGER:
2881 if (vp->length != 4) goto raw;
2883 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2884 vp->vp_integer = ntohl(vp->vp_integer);
2886 if (vp->flags.has_tag) vp->vp_integer &= 0x00ffffff;
2889 * Try to get named VALUEs
2893 dval = dict_valbyattr(vp->attribute, vp->vendor,
2896 strlcpy(vp->vp_strvalue,
2898 sizeof(vp->vp_strvalue));
2904 if (vp->length != 4) goto raw;
2906 memcpy(&vp->vp_date, vp->vp_octets, 4);
2907 vp->vp_date = ntohl(vp->vp_date);
2911 case PW_TYPE_IPADDR:
2912 if (vp->length != 4) goto raw;
2914 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2918 * IPv6 interface ID is 8 octets long.
2921 if (vp->length != 8) goto raw;
2922 /* vp->vp_ifid == vp->vp_octets */
2926 * IPv6 addresses are 16 octets long
2928 case PW_TYPE_IPV6ADDR:
2929 if (vp->length != 16) goto raw;
2930 /* vp->vp_ipv6addr == vp->vp_octets */
2934 * IPv6 prefixes are 2 to 18 octets long.
2936 * RFC 3162: The first octet is unused.
2937 * The second is the length of the prefix
2938 * the rest are the prefix data.
2940 * The prefix length can have value 0 to 128.
2942 case PW_TYPE_IPV6PREFIX:
2943 if (vp->length < 2 || vp->length > 18) goto raw;
2944 if (vp->vp_octets[1] > 128) goto raw;
2947 * FIXME: double-check that
2948 * (vp->vp_octets[1] >> 3) matches vp->length + 2
2950 if (vp->length < 18) {
2951 memset(vp->vp_octets + vp->length, 0,
2956 case PW_TYPE_SIGNED:
2957 if (vp->length != 4) goto raw;
2960 * Overload vp_integer for ntohl, which takes
2961 * uint32_t, not int32_t
2963 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2964 vp->vp_integer = ntohl(vp->vp_integer);
2965 memcpy(&vp->vp_signed, &vp->vp_integer, 4);
2970 fr_strerror_printf("data2vp_any: Internal sanity check failed");
2973 case PW_TYPE_COMBO_IP:
2974 if (vp->length == 4) {
2975 vp->type = PW_TYPE_IPADDR;
2976 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2979 } else if (vp->length == 16) {
2980 vp->type = PW_TYPE_IPV6ADDR;
2981 /* vp->vp_ipv6addr == vp->vp_octets */
2998 * Convert a top-level VSA to a VP.
3000 static ssize_t attr2vp_vsa(const RADIUS_PACKET *packet,
3001 const RADIUS_PACKET *original,
3002 const char *secret, unsigned int vendor,
3003 size_t dv_type, size_t dv_length,
3004 const uint8_t *data, size_t length,
3007 unsigned int attribute;
3008 ssize_t attrlen, my_len;
3011 if (length <= (dv_type + dv_length)) {
3012 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3019 /* data[0] must be zero */
3020 attribute = data[1] << 16;
3021 attribute |= data[2] << 8;
3022 attribute |= data[3];
3026 attribute = data[0] << 8;
3027 attribute |= data[1];
3031 attribute = data[0];
3035 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3039 switch (dv_length) {
3041 /* data[dv_type] must be zero */
3042 attrlen = data[dv_type + 1];
3046 attrlen = data[dv_type];
3054 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3059 if (attrlen <= (ssize_t) (dv_type + dv_length)) {
3060 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3065 attrlen -= (dv_type + dv_length);
3067 my_len = data2vp_any(packet, original, secret, 0,
3069 data + dv_type + dv_length, attrlen, pvp);
3070 if (my_len < 0) return my_len;
3073 if (my_len != attrlen) {
3075 fr_strerror_printf("attr2vp_vsa: Incomplete decode %d != %d",
3076 (int) my_len, (int) attrlen);
3081 return dv_type + dv_length + attrlen;
3085 * Convert one or more TLVs to VALUE_PAIRs. This function can
3086 * be called recursively...
3088 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
3089 const RADIUS_PACKET *original,
3091 unsigned int attribute, unsigned int vendor,
3093 const uint8_t *start, size_t length,
3096 size_t dv_type, dv_length;
3097 const uint8_t *data, *end;
3098 VALUE_PAIR *head, **last, *vp;
3103 * The default format for a VSA is the RFC recommended
3110 * Top-level TLVs can be of a weird format. TLVs
3111 * encapsulated in a TLV can only be in the RFC format.
3115 dv = dict_vendorbyvalue(vendor);
3118 dv_length = dv->length;
3119 /* dict.c enforces sane values on the above fields */
3123 if (nest >= fr_attr_max_tlv) {
3124 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in recursion");
3129 * The VSAs do not exactly fill the data,
3130 * The *entire* TLV is malformed.
3132 if (rad_tlv_ok(data, length, dv_type, dv_length) < 0) {
3133 VP_TRACE("TLV malformed %u.%u\n", vendor, attribute);
3134 return data2vp_raw(packet, original, secret,
3135 attribute, vendor, data, length, pvp);
3138 end = data + length;
3142 while (data < end) {
3143 unsigned int my_attr;
3144 unsigned int my_len;
3147 if ((data + dv_type + dv_length) > end) {
3148 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: Insufficient data");
3156 my_attr = attribute;
3157 my_attr |= ((data[0] & fr_attr_mask[nest + 1])
3158 << fr_attr_shift[nest + 1]);
3161 my_attr = (data[0] << 8) | data[1];
3165 my_attr = (data[1] << 16) | (data[1] << 8) | data[3];
3169 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3173 switch (dv_length) {
3180 my_len = data[dv_type + dv_length - 1];
3184 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3189 if (my_len < (dv_type + dv_length)) {
3190 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: underflow");
3195 if ((data + my_len) > end) {
3196 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: overflow");
3202 my_len -= dv_type + dv_length;
3205 * If this returns > 0, it returns "my_len"
3207 if (data2vp_any(packet, original, secret, nest + 1,
3209 data + dv_type + dv_length, my_len, &vp) < 0) {
3214 data += my_len + dv_type + dv_length;
3224 return data - start;
3229 * Group "continued" attributes together, and create VPs from them.
3230 * The caller ensures that the RADIUS packet is OK, and that the
3231 * continuations have all been checked.
3233 static ssize_t data2vp_continued(const RADIUS_PACKET *packet,
3234 const RADIUS_PACKET *original,
3236 const uint8_t *start, size_t length,
3237 VALUE_PAIR **pvp, int nest,
3238 unsigned int attribute, unsigned int vendor,
3239 int first_offset, int later_offset,
3243 uint8_t *attr, *ptr;
3244 const uint8_t *data;
3246 attr = malloc(attrlen);
3248 fr_strerror_printf("Out of memory");
3259 memcpy(ptr, data + first_offset, data[1] - first_offset);
3260 ptr += data[1] - first_offset;
3261 left -= data[1] - first_offset;
3266 if (data >= (start + length)) {
3267 fr_strerror_printf("data2vp_continued: Internal sanity check failed");
3271 memcpy(ptr, data + later_offset, data[1] - later_offset);
3272 ptr += data[1] - later_offset;
3273 left -= data[1] - later_offset;
3277 left = data2vp_any(packet, original, secret, nest,
3279 attr, attrlen, pvp);
3281 if (left < 0) return left;
3283 return data - start;
3288 * Create a "raw" VALUE_PAIR from a RADIUS attribute.
3290 ssize_t rad_attr2vp_raw(const RADIUS_PACKET *packet,
3291 const RADIUS_PACKET *original,
3293 const uint8_t *data, size_t length,
3298 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3299 fr_strerror_printf("rad_attr2vp_raw: Invalid length");
3303 my_len = data2vp_raw(packet, original, secret, data[0], 0,
3304 data + 2, data[1] - 2, pvp);
3305 if (my_len < 0) return my_len;
3312 * Get the length of the data portion of all of the contiguous
3313 * continued attributes.
3315 * 0 for "no continuation"
3316 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3318 static ssize_t wimax_attrlen(uint32_t vendor,
3319 const uint8_t *start, const uint8_t *end)
3322 const uint8_t *data = start;
3324 if ((data[8] & 0x80) == 0) return 0;
3325 total = data[7] - 3;
3328 while (data < end) {
3330 if ((data + 9) > end) return -1;
3332 if ((data[0] != PW_VENDOR_SPECIFIC) ||
3334 (memcmp(data + 2, &vendor, 4) != 0) ||
3335 (data[6] != start[6]) ||
3336 ((data[7] + 6) != data[1])) return -1;
3338 total += data[7] - 3;
3339 if ((data[8] & 0x80) == 0) break;
3348 * Get the length of the data portion of all of the contiguous
3349 * continued attributes.
3351 * 0 for "no continuation"
3352 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3354 static ssize_t extended_attrlen(const uint8_t *start, const uint8_t *end)
3357 const uint8_t *data = start;
3359 if ((data[3] & 0x80) == 0) return 0;
3360 total = data[1] - 4;
3363 while (data < end) {
3364 if ((data + 4) > end) return -1;
3366 if ((data[0] != start[0]) ||
3368 (data[2] != start[2])) return -1;
3370 total += data[1] - 4;
3371 if ((data[3] & 0x80) == 0) break;
3380 * Create WiMAX VALUE_PAIRs from a RADIUS attribute.
3382 ssize_t rad_attr2vp_wimax(const RADIUS_PACKET *packet,
3383 const RADIUS_PACKET *original,
3385 const uint8_t *data, size_t length,
3389 unsigned int attribute;
3392 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3393 fr_strerror_printf("rad_attr2vp_wimax: Invalid length");
3397 if (data[0] != PW_VENDOR_SPECIFIC) {
3398 fr_strerror_printf("rad_attr2vp_wimax: Invalid attribute");
3403 * Not enough room for a Vendor-Id. + WiMAX header
3406 return rad_attr2vp_raw(packet, original, secret,
3410 memcpy(&lvalue, data + 2, 4);
3411 lvalue = ntohl(lvalue);
3416 if (lvalue != VENDORPEC_WIMAX) {
3419 dv = dict_vendorbyvalue(lvalue);
3420 if (!dv || !dv->flags) {
3421 fr_strerror_printf("rad_attr2vp_wimax: Not a WiMAX attribute");
3427 * The WiMAX attribute is encapsulated in a VSA. If the
3428 * WiMAX length disagrees with the VSA length, it's malformed.
3430 if ((data[7] + 6) != data[1]) {
3431 return rad_attr2vp_raw(packet, original, secret,
3435 attribute = data[6];
3438 * Attribute is continued. Do some more work.
3441 my_len = wimax_attrlen(htonl(lvalue), data, data + length);
3443 return rad_attr2vp_raw(packet, original, secret,
3447 return data2vp_continued(packet, original, secret,
3448 data, length, pvp, 0,
3453 my_len = data2vp_any(packet, original, secret, 0, attribute, lvalue,
3454 data + 9, data[1] - 9, pvp);
3455 if (my_len < 0) return my_len;
3461 * Create Vendor-Specifc VALUE_PAIRs from a RADIUS attribute.
3463 ssize_t rad_attr2vp_vsa(const RADIUS_PACKET *packet,
3464 const RADIUS_PACKET *original,
3466 const uint8_t *data, size_t length,
3469 size_t dv_type, dv_length;
3474 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3475 fr_strerror_printf("rad_attr2vp_vsa: Invalid length");
3479 if (data[0] != PW_VENDOR_SPECIFIC) {
3480 fr_strerror_printf("rad_attr2vp_vsa: Invalid attribute");
3485 * Not enough room for a Vendor-Id.
3486 * Or the high octet of the Vendor-Id is set.
3488 if ((data[1] < 6) || (data[2] != 0)) {
3489 return rad_attr2vp_raw(packet, original, secret,
3493 memcpy(&lvalue, data + 2, 4);
3494 lvalue = ntohl(lvalue);
3497 * WiMAX gets its own set of magic.
3499 if (lvalue == VENDORPEC_WIMAX) {
3501 return rad_attr2vp_wimax(packet, original, secret,
3505 dv_type = dv_length = 1;
3506 dv = dict_vendorbyvalue(lvalue);
3509 dv_length = dv->length;
3511 if (dv->flags) goto wimax;
3515 * Attribute is not in the correct form.
3517 if (rad_tlv_ok(data + 6, data[1] - 6, dv_type, dv_length) < 0) {
3518 return rad_attr2vp_raw(packet, original, secret,
3522 my_len = attr2vp_vsa(packet, original, secret,
3523 lvalue, dv_type, dv_length,
3524 data + 6, data[1] - 6, pvp);
3525 if (my_len < 0) return my_len;
3528 * Incomplete decode means that something is wrong
3529 * with the attribute. Back up, and make it "raw".
3531 if (my_len != (data[1] - 6)) {
3533 return rad_attr2vp_raw(packet, original, secret,
3541 * Create an "extended" VALUE_PAIR from a RADIUS attribute.
3543 ssize_t rad_attr2vp_extended(const RADIUS_PACKET *packet,
3544 const RADIUS_PACKET *original,
3546 const uint8_t *start, size_t length,
3549 unsigned int attribute;
3552 unsigned int vendor = VENDORPEC_EXTENDED;
3553 size_t data_len = length;
3554 const uint8_t *data;
3559 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3560 fr_strerror_printf("rad_attr2vp_extended: Invalid length");
3564 da = dict_attrbyvalue(data[0], vendor);
3566 (!da->flags.extended && !da->flags.extended_flags)) {
3567 fr_strerror_printf("rad_attr2vp_extended: Attribute is not extended format");
3574 * No Extended-Type. It's a raw attribute.
3575 * Also, if there's no data following the Extended-Type,
3576 * it's a raw attribute.
3580 return rad_attr2vp_raw(packet, original, secret, start,
3585 * The attribute is "241.1", for example. Go look that
3586 * up to see what type it is.
3588 attribute = data[0];
3589 attribute |= (data[2] << fr_attr_shift[1]);
3591 da = dict_attrbyvalue(attribute, vendor);
3594 vendor = VENDORPEC_EXTENDED;
3597 if (data[1] < length) data_len = data[1];
3603 * If there's supposed to be a flag octet. If not, it's
3604 * a raw attribute. If the flag is set, it's supposed to
3607 if (da->flags.extended_flags) {
3608 if (data_len == 0) goto raw;
3610 continued = ((data[0] & 0x80) != 0);
3616 * Extended VSAs have 4 octets of
3617 * Vendor-Id followed by one octet of
3620 if (da->flags.evs) {
3621 if (data_len < 5) goto raw;
3624 * Vendor Ids can only be 24-bit.
3626 if (data[0] != 0) goto raw;
3628 vendor = ((data[1] << 16) |
3633 * Pack the *encapsulating* attribute number into
3634 * the vendor id. This number should be >= 241.
3636 vendor |= start[0] * FR_MAX_VENDOR;
3640 * Over-write the attribute with the
3643 attribute = data[4];
3649 int first_offset = 4;
3652 if (vendor != VENDORPEC_EXTENDED) first_offset += 5;
3654 my_len = extended_attrlen(start, start + length);
3655 if (my_len < 0) goto raw;
3657 if (vendor != VENDORPEC_EXTENDED) my_len -= 5;
3659 return data2vp_continued(packet, original, secret,
3660 start, length, pvp, shift,
3662 first_offset, 4, my_len);
3665 if (data2vp_any(packet, original, secret, shift,
3666 attribute, vendor, data, data_len, pvp) < 0) {
3670 return (data + data_len) - start;
3675 * Create a "standard" RFC VALUE_PAIR from the given data.
3677 ssize_t rad_attr2vp_rfc(const RADIUS_PACKET *packet,
3678 const RADIUS_PACKET *original,
3680 const uint8_t *data, size_t length,
3683 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3684 fr_strerror_printf("rad_attr2vp_rfc: Insufficient data");
3688 if (data2vp_any(packet, original, secret, 0,
3689 data[0], 0, data + 2, data[1] - 2, pvp) < 0) {
3697 * Create a "normal" VALUE_PAIR from the given data.
3699 ssize_t rad_attr2vp(const RADIUS_PACKET *packet,
3700 const RADIUS_PACKET *original,
3702 const uint8_t *data, size_t length,
3705 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3706 fr_strerror_printf("rad_attr2vp: Insufficient data");
3711 * VSAs get their own handler.
3713 if (data[0] == PW_VENDOR_SPECIFIC) {
3714 return rad_attr2vp_vsa(packet, original, secret,
3719 * Extended attribute format gets their own handler.
3721 if (dict_attrbyvalue(data[0], VENDORPEC_EXTENDED) != NULL) {
3722 return rad_attr2vp_extended(packet, original, secret,
3726 return rad_attr2vp_rfc(packet, original, secret, data, length, pvp);
3731 * Calculate/check digest, and decode radius attributes.
3733 * -1 on decoding error
3736 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
3742 radius_packet_t *hdr;
3743 VALUE_PAIR *head, **tail, *vp;
3746 * Extract attribute-value pairs
3748 hdr = (radius_packet_t *)packet->data;
3750 packet_length = packet->data_len - AUTH_HDR_LEN;
3757 * Loop over the attributes, decoding them into VPs.
3759 while (packet_length > 0) {
3763 * This may return many VPs
3765 my_len = rad_attr2vp(packet, original, secret,
3766 ptr, packet_length, &vp);
3781 * VSA's may not have been counted properly in
3782 * rad_packet_ok() above, as it is hard to count
3783 * then without using the dictionary. We
3784 * therefore enforce the limits here, too.
3786 if ((fr_max_attributes > 0) &&
3787 (num_attributes > fr_max_attributes)) {
3788 char host_ipaddr[128];
3791 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
3792 inet_ntop(packet->src_ipaddr.af,
3793 &packet->src_ipaddr.ipaddr,
3794 host_ipaddr, sizeof(host_ipaddr)),
3795 num_attributes, fr_max_attributes);
3800 packet_length -= my_len;
3804 * Merge information from the outside world into our
3807 fr_rand_seed(packet->data, AUTH_HDR_LEN);
3810 * There may be VP's already in the packet. Don't
3811 * destroy them. Instead, add the decoded attributes to
3812 * the tail of the list.
3814 for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
3826 * We assume that the passwd buffer passed is big enough.
3827 * RFC2138 says the password is max 128 chars, so the size
3828 * of the passwd buffer must be at least 129 characters.
3829 * Preferably it's just MAX_STRING_LEN.
3831 * int *pwlen is updated to the new length of the encrypted
3832 * password - a multiple of 16 bytes.
3834 int rad_pwencode(char *passwd, size_t *pwlen, const char *secret,
3835 const uint8_t *vector)
3837 FR_MD5_CTX context, old;
3838 uint8_t digest[AUTH_VECTOR_LEN];
3839 int i, n, secretlen;
3843 * RFC maximum is 128 bytes.
3845 * If length is zero, pad it out with zeros.
3847 * If the length isn't aligned to 16 bytes,
3848 * zero out the extra data.
3852 if (len > 128) len = 128;
3855 memset(passwd, 0, AUTH_PASS_LEN);
3856 len = AUTH_PASS_LEN;
3857 } else if ((len % AUTH_PASS_LEN) != 0) {
3858 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3859 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3864 * Use the secret to setup the decryption digest
3866 secretlen = strlen(secret);
3868 fr_MD5Init(&context);
3869 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3870 old = context; /* save intermediate work */
3873 * Encrypt it in place. Don't bother checking
3874 * len, as we've ensured above that it's OK.
3876 for (n = 0; n < len; n += AUTH_PASS_LEN) {
3878 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3879 fr_MD5Final(digest, &context);
3882 fr_MD5Update(&context,
3883 (uint8_t *) passwd + n - AUTH_PASS_LEN,
3885 fr_MD5Final(digest, &context);
3888 for (i = 0; i < AUTH_PASS_LEN; i++) {
3889 passwd[i + n] ^= digest[i];
3899 int rad_pwdecode(char *passwd, size_t pwlen, const char *secret,
3900 const uint8_t *vector)
3902 FR_MD5_CTX context, old;
3903 uint8_t digest[AUTH_VECTOR_LEN];
3905 size_t n, secretlen;
3908 * The RFC's say that the maximum is 128.
3909 * The buffer we're putting it into above is 254, so
3910 * we don't need to do any length checking.
3912 if (pwlen > 128) pwlen = 128;
3917 if (pwlen == 0) goto done;
3920 * Use the secret to setup the decryption digest
3922 secretlen = strlen(secret);
3924 fr_MD5Init(&context);
3925 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3926 old = context; /* save intermediate work */
3929 * The inverse of the code above.
3931 for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3933 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3934 fr_MD5Final(digest, &context);
3937 if (pwlen > AUTH_PASS_LEN) {
3938 fr_MD5Update(&context, (uint8_t *) passwd,
3942 fr_MD5Final(digest, &context);
3945 if (pwlen > (n + AUTH_PASS_LEN)) {
3946 fr_MD5Update(&context, (uint8_t *) passwd + n,
3951 for (i = 0; i < AUTH_PASS_LEN; i++) {
3952 passwd[i + n] ^= digest[i];
3957 passwd[pwlen] = '\0';
3958 return strlen(passwd);
3963 * Encode Tunnel-Password attributes when sending them out on the wire.
3965 * int *pwlen is updated to the new length of the encrypted
3966 * password - a multiple of 16 bytes.
3968 * This is per RFC-2868 which adds a two char SALT to the initial intermediate
3971 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, const char *secret,
3972 const uint8_t *vector)
3974 uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
3975 unsigned char digest[AUTH_VECTOR_LEN];
3977 int i, n, secretlen;
3982 if (len > 127) len = 127;
3985 * Shift the password 3 positions right to place a salt and original
3986 * length, tag will be added automatically on packet send
3988 for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
3992 * save original password length as first password character;
3999 * Generate salt. The RFC's say:
4001 * The high bit of salt[0] must be set, each salt in a
4002 * packet should be unique, and they should be random
4004 * So, we set the high bit, add in a counter, and then
4005 * add in some CSPRNG data. should be OK..
4007 salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
4008 (fr_rand() & 0x07));
4009 salt[1] = fr_rand();
4012 * Padd password to multiple of AUTH_PASS_LEN bytes.
4014 n = len % AUTH_PASS_LEN;
4016 n = AUTH_PASS_LEN - n;
4017 for (; n > 0; n--, len++)
4020 /* set new password length */
4024 * Use the secret to setup the decryption digest
4026 secretlen = strlen(secret);
4027 memcpy(buffer, secret, secretlen);
4029 for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
4031 memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
4032 memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
4033 fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
4035 memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
4036 fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
4039 for (i = 0; i < AUTH_PASS_LEN; i++) {
4040 passwd[i + n2] ^= digest[i];
4048 * Decode Tunnel-Password encrypted attributes.
4050 * Defined in RFC-2868, this uses a two char SALT along with the
4051 * initial intermediate value, to differentiate it from the
4054 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, const char *secret,
4055 const uint8_t *vector)
4057 FR_MD5_CTX context, old;
4058 uint8_t digest[AUTH_VECTOR_LEN];
4060 unsigned i, n, len, reallen;
4065 * We need at least a salt.
4068 fr_strerror_printf("tunnel password is too short");
4073 * There's a salt, but no password. Or, there's a salt
4074 * and a 'data_len' octet. It's wrong, but at least we
4075 * can figure out what it means: the password is empty.
4077 * Note that this means we ignore the 'data_len' field,
4078 * if the attribute length tells us that there's no
4079 * more data. So the 'data_len' field may be wrong,
4088 len -= 2; /* discount the salt */
4091 * Use the secret to setup the decryption digest
4093 secretlen = strlen(secret);
4095 fr_MD5Init(&context);
4096 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
4097 old = context; /* save intermediate work */
4100 * Set up the initial key:
4102 * b(1) = MD5(secret + vector + salt)
4104 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4105 fr_MD5Update(&context, passwd, 2);
4108 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4112 fr_MD5Final(digest, &context);
4117 * A quick check: decrypt the first octet
4118 * of the password, which is the
4119 * 'data_len' field. Ensure it's sane.
4121 reallen = passwd[2] ^ digest[0];
4122 if (reallen >= len) {
4123 fr_strerror_printf("tunnel password is too long for the attribute");
4127 fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
4131 fr_MD5Final(digest, &context);
4134 fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
4137 for (i = base; i < AUTH_PASS_LEN; i++) {
4138 passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
4143 * See make_tunnel_password, above.
4145 if (reallen > 239) reallen = 239;
4148 passwd[reallen] = 0;
4154 * Encode a CHAP password
4156 * FIXME: might not work with Ascend because
4157 * we use vp->length, and Ascend gear likes
4158 * to send an extra '\0' in the string!
4160 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
4161 VALUE_PAIR *password)
4165 uint8_t string[MAX_STRING_LEN * 2 + 1];
4166 VALUE_PAIR *challenge;
4169 * Sanity check the input parameters
4171 if ((packet == NULL) || (password == NULL)) {
4176 * Note that the password VP can be EITHER
4177 * a User-Password attribute (from a check-item list),
4178 * or a CHAP-Password attribute (the client asking
4179 * the library to encode it).
4187 memcpy(ptr, password->vp_strvalue, password->length);
4188 ptr += password->length;
4189 i += password->length;
4192 * Use Chap-Challenge pair if present,
4193 * Request-Authenticator otherwise.
4195 challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0);
4197 memcpy(ptr, challenge->vp_strvalue, challenge->length);
4198 i += challenge->length;
4200 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
4201 i += AUTH_VECTOR_LEN;
4205 fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
4212 * Seed the random number generator.
4214 * May be called any number of times.
4216 void fr_rand_seed(const void *data, size_t size)
4221 * Ensure that the pool is initialized.
4223 if (!fr_rand_initialized) {
4226 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
4228 fd = open("/dev/urandom", O_RDONLY);
4234 while (total < sizeof(fr_rand_pool.randrsl)) {
4235 this = read(fd, fr_rand_pool.randrsl,
4236 sizeof(fr_rand_pool.randrsl) - total);
4237 if ((this < 0) && (errno != EINTR)) break;
4238 if (this > 0) total += this;
4242 fr_rand_pool.randrsl[0] = fd;
4243 fr_rand_pool.randrsl[1] = time(NULL);
4244 fr_rand_pool.randrsl[2] = errno;
4247 fr_randinit(&fr_rand_pool, 1);
4248 fr_rand_pool.randcnt = 0;
4249 fr_rand_initialized = 1;
4255 * Hash the user data
4258 if (!hash) hash = fr_rand();
4259 hash = fr_hash_update(data, size, hash);
4261 fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
4266 * Return a 32-bit random number.
4268 uint32_t fr_rand(void)
4273 * Ensure that the pool is initialized.
4275 if (!fr_rand_initialized) {
4276 fr_rand_seed(NULL, 0);
4279 num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
4280 if (fr_rand_pool.randcnt >= 256) {
4281 fr_rand_pool.randcnt = 0;
4282 fr_isaac(&fr_rand_pool);
4290 * Allocate a new RADIUS_PACKET
4292 RADIUS_PACKET *rad_alloc(int newvector)
4296 if ((rp = malloc(sizeof(RADIUS_PACKET))) == NULL) {
4297 fr_strerror_printf("out of memory");
4300 memset(rp, 0, sizeof(*rp));
4306 uint32_t hash, base;
4309 * Don't expose the actual contents of the random
4313 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
4314 hash = fr_rand() ^ base;
4315 memcpy(rp->vector + i, &hash, sizeof(hash));
4318 fr_rand(); /* stir the pool again */
4323 RADIUS_PACKET *rad_alloc_reply(RADIUS_PACKET *packet)
4325 RADIUS_PACKET *reply;
4327 if (!packet) return NULL;
4329 reply = rad_alloc(0);
4330 if (!reply) return NULL;
4333 * Initialize the fields from the request.
4335 reply->sockfd = packet->sockfd;
4336 reply->dst_ipaddr = packet->src_ipaddr;
4337 reply->src_ipaddr = packet->dst_ipaddr;
4338 reply->dst_port = packet->src_port;
4339 reply->src_port = packet->dst_port;
4340 reply->id = packet->id;
4341 reply->code = 0; /* UNKNOWN code */
4342 memcpy(reply->vector, packet->vector,
4343 sizeof(reply->vector));
4346 reply->data_len = 0;
4353 * Free a RADIUS_PACKET
4355 void rad_free(RADIUS_PACKET **radius_packet_ptr)
4357 RADIUS_PACKET *radius_packet;
4359 if (!radius_packet_ptr || !*radius_packet_ptr) return;
4360 radius_packet = *radius_packet_ptr;
4362 free(radius_packet->data);
4364 pairfree(&radius_packet->vps);
4366 free(radius_packet);
4368 *radius_packet_ptr = NULL;