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);
235 * Wrapper for sendto which handles sendfromto, IPv6, and all
236 * possible combinations.
238 static int rad_sendto(int sockfd, void *data, size_t data_len, int flags,
239 fr_ipaddr_t *src_ipaddr, int src_port,
240 fr_ipaddr_t *dst_ipaddr, int dst_port)
243 struct sockaddr_storage dst;
244 socklen_t sizeof_dst;
246 #ifdef WITH_UDPFROMTO
247 struct sockaddr_storage src;
248 socklen_t sizeof_src;
250 fr_ipaddr2sockaddr(src_ipaddr, src_port, &src, &sizeof_src);
252 src_port = src_port; /* -Wunused */
255 if (!fr_ipaddr2sockaddr(dst_ipaddr, dst_port, &dst, &sizeof_dst)) {
259 #ifdef WITH_UDPFROMTO
261 * And if they don't specify a source IP address, don't
264 if (((dst_ipaddr->af == AF_INET) || (dst_ipaddr->af == AF_INET6)) &&
265 (src_ipaddr->af != AF_UNSPEC) &&
266 !fr_inaddr_any(src_ipaddr)) {
267 rcode = sendfromto(sockfd, data, data_len, flags,
268 (struct sockaddr *)&src, sizeof_src,
269 (struct sockaddr *)&dst, sizeof_dst);
273 src_ipaddr = src_ipaddr; /* -Wunused */
277 * No udpfromto, fail gracefully.
279 rcode = sendto(sockfd, data, data_len, flags,
280 (struct sockaddr *) &dst, sizeof_dst);
282 DEBUG("rad_send() failed: %s\n", strerror(errno));
289 void rad_recv_discard(int sockfd)
292 struct sockaddr_storage src;
293 socklen_t sizeof_src = sizeof(src);
295 recvfrom(sockfd, header, sizeof(header), 0,
296 (struct sockaddr *)&src, &sizeof_src);
300 ssize_t rad_recv_header(int sockfd, fr_ipaddr_t *src_ipaddr, int *src_port,
303 ssize_t data_len, packet_len;
305 struct sockaddr_storage src;
306 socklen_t sizeof_src = sizeof(src);
308 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
309 (struct sockaddr *)&src, &sizeof_src);
311 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
316 * Too little data is available, discard the packet.
319 recvfrom(sockfd, header, sizeof(header), 0,
320 (struct sockaddr *)&src, &sizeof_src);
323 } else { /* we got 4 bytes of data. */
325 * See how long the packet says it is.
327 packet_len = (header[2] * 256) + header[3];
330 * The length in the packet says it's less than
331 * a RADIUS header length: discard it.
333 if (packet_len < AUTH_HDR_LEN) {
334 recvfrom(sockfd, header, sizeof(header), 0,
335 (struct sockaddr *)&src, &sizeof_src);
339 * Enforce RFC requirements, for sanity.
340 * Anything after 4k will be discarded.
342 } else if (packet_len > MAX_PACKET_LEN) {
343 recvfrom(sockfd, header, sizeof(header), 0,
344 (struct sockaddr *)&src, &sizeof_src);
350 * Convert AF. If unknown, discard packet.
352 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, src_port)) {
353 recvfrom(sockfd, header, sizeof(header), 0,
354 (struct sockaddr *)&src, &sizeof_src);
361 * The packet says it's this long, but the actual UDP
362 * size could still be smaller.
369 * wrapper for recvfrom, which handles recvfromto, IPv6, and all
370 * possible combinations.
372 static ssize_t rad_recvfrom(int sockfd, uint8_t **pbuf, int flags,
373 fr_ipaddr_t *src_ipaddr, uint16_t *src_port,
374 fr_ipaddr_t *dst_ipaddr, uint16_t *dst_port)
376 struct sockaddr_storage src;
377 struct sockaddr_storage dst;
378 socklen_t sizeof_src = sizeof(src);
379 socklen_t sizeof_dst = sizeof(dst);
386 memset(&src, 0, sizeof_src);
387 memset(&dst, 0, sizeof_dst);
390 * Get address family, etc. first, so we know if we
391 * need to do udpfromto.
393 * FIXME: udpfromto also does this, but it's not
394 * a critical problem.
396 if (getsockname(sockfd, (struct sockaddr *)&dst,
397 &sizeof_dst) < 0) return -1;
400 * Read the length of the packet, from the packet.
401 * This lets us allocate the buffer to use for
402 * reading the rest of the packet.
404 data_len = recvfrom(sockfd, header, sizeof(header), MSG_PEEK,
405 (struct sockaddr *)&src, &sizeof_src);
407 if ((errno == EAGAIN) || (errno == EINTR)) return 0;
412 * Too little data is available, discard the packet.
415 recvfrom(sockfd, header, sizeof(header), flags,
416 (struct sockaddr *)&src, &sizeof_src);
419 } else { /* we got 4 bytes of data. */
421 * See how long the packet says it is.
423 len = (header[2] * 256) + header[3];
426 * The length in the packet says it's less than
427 * a RADIUS header length: discard it.
429 if (len < AUTH_HDR_LEN) {
430 recvfrom(sockfd, header, sizeof(header), flags,
431 (struct sockaddr *)&src, &sizeof_src);
435 * Enforce RFC requirements, for sanity.
436 * Anything after 4k will be discarded.
438 } else if (len > MAX_PACKET_LEN) {
439 recvfrom(sockfd, header, sizeof(header), flags,
440 (struct sockaddr *)&src, &sizeof_src);
449 * Receive the packet. The OS will discard any data in the
450 * packet after "len" bytes.
452 #ifdef WITH_UDPFROMTO
453 if ((dst.ss_family == AF_INET) || (dst.ss_family == AF_INET6)) {
454 data_len = recvfromto(sockfd, buf, len, flags,
455 (struct sockaddr *)&src, &sizeof_src,
456 (struct sockaddr *)&dst, &sizeof_dst);
460 * No udpfromto, fail gracefully.
462 data_len = recvfrom(sockfd, buf, len, flags,
463 (struct sockaddr *)&src, &sizeof_src);
469 if (!fr_sockaddr2ipaddr(&src, sizeof_src, src_ipaddr, &port)) {
471 return -1; /* Unknown address family, Die Die Die! */
475 fr_sockaddr2ipaddr(&dst, sizeof_dst, dst_ipaddr, &port);
479 * Different address families should never happen.
481 if (src.ss_family != dst.ss_family) {
487 * Tell the caller about the data
495 #define AUTH_PASS_LEN (AUTH_VECTOR_LEN)
496 /*************************************************************************
498 * Function: make_secret
500 * Purpose: Build an encrypted secret value to return in a reply
501 * packet. The secret is hidden by xoring with a MD5 digest
502 * created from the shared secret and the authentication
503 * vector. We put them into MD5 in the reverse order from
504 * that used when encrypting passwords to RADIUS.
506 *************************************************************************/
507 static void make_secret(uint8_t *digest, const uint8_t *vector,
508 const char *secret, const uint8_t *value)
513 fr_MD5Init(&context);
514 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
515 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
516 fr_MD5Final(digest, &context);
518 for ( i = 0; i < AUTH_VECTOR_LEN; i++ ) {
519 digest[i] ^= value[i];
523 #define MAX_PASS_LEN (128)
524 static void make_passwd(uint8_t *output, ssize_t *outlen,
525 const uint8_t *input, size_t inlen,
526 const char *secret, const uint8_t *vector)
528 FR_MD5_CTX context, old;
529 uint8_t digest[AUTH_VECTOR_LEN];
530 uint8_t passwd[MAX_PASS_LEN];
535 * If the length is zero, round it up.
539 if (len > MAX_PASS_LEN) len = MAX_PASS_LEN;
541 memcpy(passwd, input, len);
542 memset(passwd + len, 0, sizeof(passwd) - len);
548 else if ((len & 0x0f) != 0) {
554 fr_MD5Init(&context);
555 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
561 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
563 for (n = 0; n < len; n += AUTH_PASS_LEN) {
566 fr_MD5Update(&context,
567 passwd + n - AUTH_PASS_LEN,
571 fr_MD5Final(digest, &context);
572 for (i = 0; i < AUTH_PASS_LEN; i++) {
573 passwd[i + n] ^= digest[i];
577 memcpy(output, passwd, len);
580 static void make_tunnel_passwd(uint8_t *output, ssize_t *outlen,
581 const uint8_t *input, size_t inlen, size_t room,
582 const char *secret, const uint8_t *vector)
584 FR_MD5_CTX context, old;
585 uint8_t digest[AUTH_VECTOR_LEN];
586 uint8_t passwd[MAX_STRING_LEN + AUTH_VECTOR_LEN];
593 if (room > 253) room = 253;
596 * Account for 2 bytes of the salt, and round the room
597 * available down to the nearest multiple of 16. Then,
598 * subtract one from that to account for the length byte,
599 * and the resulting number is the upper bound on the data
602 * We could short-cut this calculation just be forcing
603 * inlen to be no more than 239. It would work for all
604 * VSA's, as we don't pack multiple VSA's into one
607 * However, this calculation is more general, if a little
608 * complex. And it will work in the future for all possible
609 * kinds of weird attribute packing.
612 room -= (room & 0x0f);
615 if (inlen > room) inlen = room;
618 * Length of the encrypted data is password length plus
619 * one byte for the length of the password.
622 if ((len & 0x0f) != 0) {
626 *outlen = len + 2; /* account for the salt */
629 * Copy the password over.
631 memcpy(passwd + 3, input, inlen);
632 memset(passwd + 3 + inlen, 0, sizeof(passwd) - 3 - inlen);
635 * Generate salt. The RFC's say:
637 * The high bit of salt[0] must be set, each salt in a
638 * packet should be unique, and they should be random
640 * So, we set the high bit, add in a counter, and then
641 * add in some CSPRNG data. should be OK..
643 passwd[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
645 passwd[1] = fr_rand();
646 passwd[2] = inlen; /* length of the password string */
648 fr_MD5Init(&context);
649 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
652 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
653 fr_MD5Update(&context, &passwd[0], 2);
655 for (n = 0; n < len; n += AUTH_PASS_LEN) {
658 fr_MD5Update(&context,
659 passwd + 2 + n - AUTH_PASS_LEN,
663 fr_MD5Final(digest, &context);
665 for (i = 0; i < AUTH_PASS_LEN; i++) {
666 passwd[i + 2 + n] ^= digest[i];
669 memcpy(output, passwd, len + 2);
672 extern int fr_attr_max_tlv;
673 extern int fr_attr_shift[];
674 extern int fr_attr_mask[];
676 static int do_next_tlv(const VALUE_PAIR *vp, int nest)
678 unsigned int tlv1, tlv2;
680 if (nest > fr_attr_max_tlv) return 0;
685 * Keep encoding TLVs which have the same scope.
686 * e.g. two attributes of:
687 * ATTR.TLV1.TLV2.TLV3 = data1
688 * ATTR.TLV1.TLV2.TLV4 = data2
689 * both get put into a container of "ATTR.TLV1.TLV2"
693 * Nothing to follow, we're done.
695 if (!vp->next) return 0;
698 * Not from the same vendor, skip it.
700 if (vp->vendor != vp->next->vendor) return 0;
703 * In a different TLV space, skip it.
705 tlv1 = vp->attribute;
706 tlv2 = vp->next->attribute;
708 tlv1 &= ((1 << fr_attr_shift[nest]) - 1);
709 tlv2 &= ((1 << fr_attr_shift[nest]) - 1);
711 if (tlv1 != tlv2) return 0;
717 static ssize_t vp2data_any(const RADIUS_PACKET *packet,
718 const RADIUS_PACKET *original,
719 const char *secret, int nest,
720 const VALUE_PAIR **pvp,
721 uint8_t *start, size_t room);
723 static ssize_t vp2attr_rfc(const RADIUS_PACKET *packet,
724 const RADIUS_PACKET *original,
725 const char *secret, const VALUE_PAIR **pvp,
726 unsigned int attribute, uint8_t *ptr, size_t room);
729 * This is really a sub-function of vp2data_any. It encodes
730 * the *data* portion of the TLV, and assumes that the encapsulating
731 * attribute has already been encoded.
733 static ssize_t vp2data_tlvs(const RADIUS_PACKET *packet,
734 const RADIUS_PACKET *original,
735 const char *secret, int nest,
736 const VALUE_PAIR **pvp,
737 uint8_t *start, size_t room)
741 uint8_t *ptr = start;
742 const VALUE_PAIR *old_vp;
743 const VALUE_PAIR *vp = *pvp;
746 const VALUE_PAIR *svp = vp;
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;
790 if ((fr_debug_flag > 3) && fr_log_fp) {
793 da = dict_attrbyvalue(svp->attribute & ((1 << fr_attr_shift[nest ]) - 1), svp->vendor);
794 if (da) fprintf(fr_log_fp, "\t%s = ...\n", da->name);
803 * Encodes the data portion of an attribute.
804 * Returns -1 on error, or the length of the data portion.
806 static ssize_t vp2data_any(const RADIUS_PACKET *packet,
807 const RADIUS_PACKET *original,
808 const char *secret, int nest,
809 const VALUE_PAIR **pvp,
810 uint8_t *start, size_t room)
815 uint8_t *ptr = start;
817 const VALUE_PAIR *vp = *pvp;
820 * See if we need to encode a TLV. The low portion of
821 * the attribute has already been placed into the packer.
822 * If there are still attribute bytes left, then go
823 * encode them as TLVs.
825 * If we cared about the stack, we could unroll the loop.
827 VP_TRACE("vp2data_any: %u attr %u -> %u\n",
828 nest, vp->attribute, vp->attribute >> fr_attr_shift[nest + 1]);
829 if (vp->flags.is_tlv && (nest < fr_attr_max_tlv) &&
830 ((vp->attribute >> fr_attr_shift[nest + 1]) != 0)) {
831 return vp2data_tlvs(packet, original, secret, nest + 1, pvp,
834 VP_TRACE("vp2data_any: Encoding %s\n", vp->name);
837 * Set up the default sources for the data.
839 data = vp->vp_octets;
846 case PW_TYPE_IPV6ADDR:
847 case PW_TYPE_IPV6PREFIX:
848 case PW_TYPE_ABINARY:
849 /* nothing more to do */
853 len = 1; /* just in case */
854 array[0] = vp->vp_integer & 0xff;
859 len = 2; /* just in case */
860 array[0] = (vp->vp_integer >> 8) & 0xff;
861 array[1] = vp->vp_integer & 0xff;
865 case PW_TYPE_INTEGER:
866 len = 4; /* just in case */
867 lvalue = htonl(vp->vp_integer);
868 memcpy(array, &lvalue, sizeof(lvalue));
873 data = (const uint8_t *) &vp->vp_ipaddr;
874 len = 4; /* just in case */
878 * There are no tagged date attributes.
881 lvalue = htonl(vp->vp_date);
882 data = (const uint8_t *) &lvalue;
883 len = 4; /* just in case */
890 len = 4; /* just in case */
891 slvalue = htonl(vp->vp_signed);
892 memcpy(array, &slvalue, sizeof(slvalue));
899 fr_strerror_printf("ERROR: Cannot encode NULL TLV");
905 default: /* unknown type: ignore it */
906 fr_strerror_printf("ERROR: Unknown attribute type %d", vp->type);
911 * Bound the data to the calling size
913 if (len > (ssize_t) room) len = room;
916 * Encrypt the various password styles
918 * Attributes with encrypted values MUST be less than
921 switch (vp->flags.encrypt) {
922 case FLAG_ENCRYPT_USER_PASSWORD:
923 make_passwd(ptr, &len, data, len,
924 secret, packet->vector);
927 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
929 if (vp->flags.has_tag) lvalue = 1;
932 * Check if there's enough room. If there isn't,
933 * we discard the attribute.
935 * This is ONLY a problem if we have multiple VSA's
936 * in one Vendor-Specific, though.
938 if (room < (18 + lvalue)) return 0;
940 switch (packet->code) {
941 case PW_AUTHENTICATION_ACK:
942 case PW_AUTHENTICATION_REJECT:
943 case PW_ACCESS_CHALLENGE:
946 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->name);
950 if (lvalue) ptr[0] = vp->flags.tag;
951 make_tunnel_passwd(ptr + lvalue, &len, data, len,
953 secret, original->vector);
955 case PW_ACCOUNTING_REQUEST:
956 case PW_DISCONNECT_REQUEST:
958 ptr[0] = vp->flags.tag;
959 make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
960 secret, packet->vector);
966 * The code above ensures that this attribute
969 case FLAG_ENCRYPT_ASCEND_SECRET:
970 make_secret(ptr, packet->vector, secret, data);
971 len = AUTH_VECTOR_LEN;
976 if (vp->flags.has_tag && TAG_VALID(vp->flags.tag)) {
977 if (vp->type == PW_TYPE_STRING) {
978 if (len > ((ssize_t) (room - 1))) len = room - 1;
979 ptr[0] = vp->flags.tag;
981 } else if (vp->type == PW_TYPE_INTEGER) {
982 array[0] = vp->flags.tag;
983 } /* else it can't be any other type */
985 memcpy(ptr, data, len);
987 } /* switch over encryption flags */
990 return len + (ptr - start);;
993 static ssize_t attr_shift(const uint8_t *start, const uint8_t *end,
994 uint8_t *ptr, int hdr_len, ssize_t len,
995 int flag_offset, int vsa_offset)
997 int check_len = len - ptr[1];
998 int total = len + hdr_len;
1001 * Pass 1: Check if the addition of the headers
1002 * overflows the available room. If so, return
1003 * what we were capable of encoding.
1006 while (check_len > (255 - hdr_len)) {
1008 check_len -= (255 - hdr_len);
1012 * Note that this results in a number of attributes maybe
1013 * being marked as "encoded", but which aren't in the
1014 * packet. Oh well. The solution is to fix the
1015 * "vp2data_any" function to take into account the header
1018 if ((ptr + ptr[1] + total) > end) {
1019 return (ptr + ptr[1]) - start;
1023 * Pass 2: Now that we know there's enough room,
1024 * re-arrange the data to form a set of valid
1025 * RADIUS attributes.
1028 int sublen = 255 - ptr[1];
1030 if (len <= sublen) {
1035 memmove(ptr + 255 + hdr_len, ptr + 255, sublen);
1036 memcpy(ptr + 255, ptr, hdr_len);
1038 if (vsa_offset) ptr[vsa_offset] += sublen;
1039 ptr[flag_offset] |= 0x80;
1043 if (vsa_offset) ptr[vsa_offset] = 3;
1047 if (vsa_offset) ptr[vsa_offset] += len;
1049 return (ptr + ptr[1]) - start;
1054 * Encode an "extended" attribute.
1056 int rad_vp2extended(const RADIUS_PACKET *packet,
1057 const RADIUS_PACKET *original,
1058 const char *secret, const VALUE_PAIR **pvp,
1059 uint8_t *ptr, size_t room)
1064 uint8_t *start = ptr;
1065 const VALUE_PAIR *vp = *pvp;
1067 VP_TRACE("rad_vp2extended %s\n", vp->name);
1068 if (vp->vendor < VENDORPEC_EXTENDED) {
1069 fr_strerror_printf("rad_vp2extended called for non-extended attribute");
1073 if (room < 3) return 0;
1075 ptr[0] = vp->attribute & 0xff;
1078 if (vp->flags.extended) {
1079 ptr[2] = (vp->attribute & 0xff00) >> 8;
1081 } else if (vp->flags.extended_flags) {
1082 if (room < 4) return 0;
1085 ptr[2] = (vp->attribute & 0xff00) >> 8;
1090 * Only "flagged" attributes can be longer than one
1093 if (!vp->flags.extended_flags && (room > 255)) {
1100 if (vp->flags.evs) {
1101 uint8_t *evs = ptr + ptr[1];
1103 if (room < (size_t) (ptr[1] + 5)) return 0;
1106 * RADIUS Attribute Type is packed into the high byte
1107 * of the Vendor Id. So over-write it in the packet.
1109 * And hard-code Extended-Type to Vendor-Specific.
1111 ptr[0] = (vp->vendor >> 24) & 0xff;
1114 evs[0] = 0; /* always zero */
1115 evs[1] = (vp->vendor >> 16) & 0xff;
1116 evs[2] = (vp->vendor >> 8) & 0xff;
1117 evs[3] = vp->vendor & 0xff;
1118 evs[4] = vp->attribute & 0xff;
1125 len = vp2data_any(packet, original, secret, nest,
1126 pvp, ptr + ptr[1], room - hdr_len);
1127 if (len < 0) return len;
1130 * There may be more than 252 octets of data encoded in
1131 * the attribute. If so, move the data up in the packet,
1132 * and copy the existing header over. Set the "M" flag ONLY
1133 * after copying the rest of the data.
1135 if (vp->flags.extended_flags && (len > (255 - ptr[1]))) {
1136 return attr_shift(start, start + room, ptr, 4, len, 3, 0);
1142 if ((fr_debug_flag > 3) && fr_log_fp) {
1145 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1146 if (!vp->flags.extended_flags) {
1147 fprintf(fr_log_fp, "%02x ", ptr[2]);
1150 fprintf(fr_log_fp, "%02x %02x ", ptr[2], ptr[3]);
1154 if (vp->flags.evs) {
1155 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) %02x ",
1156 ptr[jump], ptr[jump + 1],
1157 ptr[jump + 2], ptr[jump + 3],
1158 ((ptr[jump + 1] << 16) |
1159 (ptr[jump + 2] << 8) |
1165 print_hex_data(ptr + jump, len, 3);
1169 return (ptr + ptr[1]) - start;
1174 * Encode a WiMAX attribute.
1176 int rad_vp2wimax(const RADIUS_PACKET *packet,
1177 const RADIUS_PACKET *original,
1178 const char *secret, const VALUE_PAIR **pvp,
1179 uint8_t *ptr, size_t room)
1184 uint8_t *start = ptr;
1185 const VALUE_PAIR *vp = *pvp;
1188 * Double-check for WiMAX format.
1190 if (!vp->flags.wimax) {
1191 fr_strerror_printf("rad_vp2wimax called for non-WIMAX VSA");
1196 * Not enough room for:
1197 * attr, len, vendor-id, vsa, vsalen, continuation
1199 if (room < 9) return 0;
1202 * Build the Vendor-Specific header
1205 ptr[0] = PW_VENDOR_SPECIFIC;
1207 lvalue = htonl(vp->vendor);
1208 memcpy(ptr + 2, &lvalue, 4);
1209 ptr[6] = (vp->attribute & fr_attr_mask[1]);
1211 ptr[8] = 0; /* continuation byte */
1215 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1],
1217 if (len <= 0) return len;
1220 * There may be more than 252 octets of data encoded in
1221 * the attribute. If so, move the data up in the packet,
1222 * and copy the existing header over. Set the "C" flag
1223 * ONLY after copying the rest of the data.
1225 if (len > (255 - ptr[1])) {
1226 return attr_shift(start, start + room, ptr, hdr_len, len, 8, 7);
1233 if ((fr_debug_flag > 3) && fr_log_fp) {
1234 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) %02x %02x %02x ",
1236 ptr[2], ptr[3], ptr[4], ptr[5],
1237 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5],
1238 ptr[6], ptr[7], ptr[8]);
1239 print_hex_data(ptr + 9, len, 3);
1243 return (ptr + ptr[1]) - start;
1247 * Encode an RFC format TLV. This could be a standard attribute,
1248 * or a TLV data type. If it's a standard attribute, then
1249 * vp->attribute == attribute. Otherwise, attribute may be
1252 static ssize_t vp2attr_rfc(const RADIUS_PACKET *packet,
1253 const RADIUS_PACKET *original,
1254 const char *secret, const VALUE_PAIR **pvp,
1255 unsigned int attribute, uint8_t *ptr, size_t room)
1259 if (room < 2) return 0;
1261 ptr[0] = attribute & 0xff;
1264 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1266 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1], room);
1267 if (len < 0) return len;
1272 if ((fr_debug_flag > 3) && fr_log_fp) {
1273 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1274 print_hex_data(ptr + 2, len, 3);
1283 * Encode a VSA which is a TLV. If it's in the RFC format, call
1284 * vp2attr_rfc. Otherwise, encode it here.
1286 static ssize_t vp2attr_vsa(const RADIUS_PACKET *packet,
1287 const RADIUS_PACKET *original,
1288 const char *secret, const VALUE_PAIR **pvp,
1289 unsigned int attribute, unsigned int vendor,
1290 uint8_t *ptr, size_t room)
1294 const VALUE_PAIR *vp = *pvp;
1297 * Unknown vendor: RFC format.
1298 * Known vendor and RFC format: go do that.
1300 VP_TRACE("Encoding VSA %u.%u\n", vendor, attribute);
1301 dv = dict_vendorbyvalue(vendor);
1302 VP_TRACE("Flags %d %d\n", vp->flags.is_tlv, vp->flags.has_tlv);
1304 (!vp->flags.is_tlv && (dv->type == 1) && (dv->length == 1))) {
1305 VP_TRACE("Encoding RFC %u.%u\n", vendor, attribute);
1306 return vp2attr_rfc(packet, original, secret, pvp,
1307 attribute, ptr, room);
1312 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1313 " type %u", (unsigned) dv->type);
1317 ptr[0] = 0; /* attr must be 24-bit */
1318 ptr[1] = (attribute >> 16) & 0xff;
1319 ptr[2] = (attribute >> 8) & 0xff;
1320 ptr[3] = attribute & 0xff;
1324 ptr[0] = (attribute >> 8) & 0xff;
1325 ptr[1] = attribute & 0xff;
1329 ptr[0] = attribute & 0xff;
1333 switch (dv->length) {
1335 fr_strerror_printf("vp2attr_vsa: Internal sanity check failed,"
1336 " length %u", (unsigned) dv->length);
1344 ptr[dv->type + 1] = dv->type + 2;
1348 ptr[dv->type] = dv->type + 1;
1353 if (room > ((unsigned) 255 - (dv->type + dv->length))) {
1354 room = 255 - (dv->type + dv->length);
1357 len = vp2data_any(packet, original, secret, 0, pvp,
1358 ptr + dv->type + dv->length, room);
1359 if (len < 0) return len;
1361 if (dv->length) ptr[dv->type + dv->length - 1] += len;
1364 if ((fr_debug_flag > 3) && fr_log_fp) {
1370 if ((fr_debug_flag > 3) && fr_log_fp)
1371 fprintf(fr_log_fp, "\t\t%02x%02x%02x%02x ",
1372 ptr[0], ptr[1], ptr[2], ptr[3]);
1376 if ((fr_debug_flag > 3) && fr_log_fp)
1377 fprintf(fr_log_fp, "\t\t%02x%02x ",
1382 if ((fr_debug_flag > 3) && fr_log_fp)
1383 fprintf(fr_log_fp, "\t\t%02x ", ptr[0]);
1387 switch (dv->length) {
1392 fprintf(fr_log_fp, " ");
1396 fprintf(fr_log_fp, "%02x ",
1401 fprintf(fr_log_fp, "%02x%02x ",
1402 ptr[dv->type], ptr[dv->type] + 1);
1406 print_hex_data(ptr + dv->type + dv->length, len, 3);
1410 return dv->type + dv->length + len;
1415 * Encode a Vendor-Specific attribute.
1417 int rad_vp2vsa(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1418 const char *secret, const VALUE_PAIR **pvp, uint8_t *ptr,
1423 const VALUE_PAIR *vp = *pvp;
1426 * Double-check for WiMAX format.
1428 if (vp->flags.wimax) {
1429 return rad_vp2wimax(packet, original, secret, pvp,
1433 if (vp->vendor > FR_MAX_VENDOR) {
1434 fr_strerror_printf("rad_vp2vsa: Invalid arguments");
1439 * Not enough room for:
1440 * attr, len, vendor-id
1442 if (room < 6) return 0;
1445 * Build the Vendor-Specific header
1447 ptr[0] = PW_VENDOR_SPECIFIC;
1449 lvalue = htonl(vp->vendor);
1450 memcpy(ptr + 2, &lvalue, 4);
1452 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1454 len = vp2attr_vsa(packet, original, secret, pvp,
1455 vp->attribute, vp->vendor,
1456 ptr + ptr[1], room);
1457 if (len < 0) return len;
1460 if ((fr_debug_flag > 3) && fr_log_fp) {
1461 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) ",
1463 ptr[2], ptr[3], ptr[4], ptr[5],
1464 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5]);
1465 print_hex_data(ptr + 6, len, 3);
1476 * Encode an RFC standard attribute 1..255
1478 int rad_vp2rfc(const RADIUS_PACKET *packet,
1479 const RADIUS_PACKET *original,
1480 const char *secret, const VALUE_PAIR **pvp,
1481 uint8_t *ptr, size_t room)
1483 const VALUE_PAIR *vp = *pvp;
1485 if (vp->vendor != 0) {
1486 fr_strerror_printf("rad_vp2rfc called with VSA");
1490 if ((vp->attribute == 0) || (vp->attribute > 255)) {
1491 fr_strerror_printf("rad_vp2rfc called with non-standard attribute %u", vp->attribute);
1495 if ((vp->length == 0) &&
1496 (vp->attribute != PW_CHARGEABLE_USER_IDENTITY)) {
1500 return vp2attr_rfc(packet, original, secret, pvp, vp->attribute,
1506 * Parse a data structure into a RADIUS attribute.
1508 int rad_vp2attr(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1509 const char *secret, const VALUE_PAIR **pvp, uint8_t *start,
1512 const VALUE_PAIR *vp;
1514 if (!pvp || !*pvp || !start || (room <= 2)) return -1;
1519 * RFC format attributes take the fast path.
1521 if (vp->vendor == 0) {
1522 if (vp->attribute > 255) return 0;
1525 * Message-Authenticator is hard-coded.
1527 if (vp->attribute == PW_MESSAGE_AUTHENTICATOR) {
1528 if (room < 18) return -1;
1530 start[0] = PW_MESSAGE_AUTHENTICATOR;
1532 memset(start + 2, 0, 16);
1534 if ((fr_debug_flag > 3) && fr_log_fp) {
1535 fprintf(fr_log_fp, "\t\t50 12 ...\n");
1539 *pvp = (*pvp)->next;
1543 return rad_vp2rfc(packet, original, secret, pvp,
1547 if (vp->vendor > FR_MAX_VENDOR) {
1548 return rad_vp2extended(packet, original, secret, pvp,
1552 if (vp->flags.wimax) {
1553 return rad_vp2wimax(packet, original, secret, pvp,
1557 return rad_vp2vsa(packet, original, secret, pvp,
1565 int rad_encode(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1568 radius_packet_t *hdr;
1570 uint16_t total_length;
1572 const VALUE_PAIR *reply;
1574 char ip_buffer[128];
1577 * A 4K packet, aligned on 64-bits.
1579 uint64_t data[MAX_PACKET_LEN / sizeof(uint64_t)];
1581 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1582 what = fr_packet_codes[packet->code];
1587 DEBUG("Sending %s of id %d to %s port %d\n",
1589 inet_ntop(packet->dst_ipaddr.af,
1590 &packet->dst_ipaddr.ipaddr,
1591 ip_buffer, sizeof(ip_buffer)),
1595 * Double-check some things based on packet code.
1597 switch (packet->code) {
1598 case PW_AUTHENTICATION_ACK:
1599 case PW_AUTHENTICATION_REJECT:
1600 case PW_ACCESS_CHALLENGE:
1602 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1608 * These packet vectors start off as all zero.
1610 case PW_ACCOUNTING_REQUEST:
1611 case PW_DISCONNECT_REQUEST:
1612 case PW_COA_REQUEST:
1613 memset(packet->vector, 0, sizeof(packet->vector));
1621 * Use memory on the stack, until we know how
1622 * large the packet will be.
1624 hdr = (radius_packet_t *) data;
1627 * Build standard header
1629 hdr->code = packet->code;
1630 hdr->id = packet->id;
1632 memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1634 total_length = AUTH_HDR_LEN;
1637 * Load up the configuration values for the user
1643 * FIXME: Loop twice over the reply list. The first time,
1644 * calculate the total length of data. The second time,
1645 * allocate the memory, and fill in the VP's.
1647 * Hmm... this may be slower than just doing a small
1652 * Loop over the reply attributes for the packet.
1654 reply = packet->vps;
1657 * Ignore non-wire attributes, but allow extended
1660 if ((reply->vendor == 0) &&
1661 ((reply->attribute & 0xFFFF) >= 256) &&
1662 !reply->flags.extended && !reply->flags.extended_flags) {
1665 * Permit the admin to send BADLY formatted
1666 * attributes with a debug build.
1668 if (reply->attribute == PW_RAW_ATTRIBUTE) {
1669 memcpy(ptr, reply->vp_octets, reply->length);
1670 len = reply->length;
1671 reply = reply->next;
1675 reply = reply->next;
1680 * Set the Message-Authenticator to the correct
1681 * length and initial value.
1683 if (reply->attribute == PW_MESSAGE_AUTHENTICATOR) {
1685 * Cache the offset to the
1686 * Message-Authenticator
1688 packet->offset = total_length;
1692 * Print out ONLY the attributes which
1693 * we're sending over the wire, and print
1694 * them out BEFORE they're encrypted.
1698 len = rad_vp2attr(packet, original, secret, &reply, ptr,
1699 ((uint8_t *) data) + sizeof(data) - ptr);
1700 if (len < 0) return -1;
1703 * Failed to encode the attribute, likely because
1704 * the packet is full.
1707 (total_length > (sizeof(data) - 2 - reply->length))) {
1708 DEBUG("WARNING: Attributes are too long for packet. Discarding data past %d bytes", total_length);
1713 next: /* Used only for Raw-Attribute */
1716 total_length += len;
1717 } /* done looping over all attributes */
1720 * Fill in the rest of the fields, and copy the data over
1721 * from the local stack to the newly allocated memory.
1723 * Yes, all this 'memcpy' is slow, but it means
1724 * that we only allocate the minimum amount of
1725 * memory for a request.
1727 packet->data_len = total_length;
1728 packet->data = (uint8_t *) malloc(packet->data_len);
1729 if (!packet->data) {
1730 fr_strerror_printf("Out of memory");
1734 memcpy(packet->data, hdr, packet->data_len);
1735 hdr = (radius_packet_t *) packet->data;
1737 total_length = htons(total_length);
1738 memcpy(hdr->length, &total_length, sizeof(total_length));
1745 * Sign a previously encoded packet.
1747 int rad_sign(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1750 radius_packet_t *hdr = (radius_packet_t *)packet->data;
1753 * It wasn't assigned an Id, this is bad!
1755 if (packet->id < 0) {
1756 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1760 if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1761 (packet->offset < 0)) {
1762 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1767 * If there's a Message-Authenticator, update it
1768 * now, BEFORE updating the authentication vector.
1770 if (packet->offset > 0) {
1771 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1773 switch (packet->code) {
1774 case PW_ACCOUNTING_REQUEST:
1775 case PW_ACCOUNTING_RESPONSE:
1776 case PW_DISCONNECT_REQUEST:
1777 case PW_DISCONNECT_ACK:
1778 case PW_DISCONNECT_NAK:
1779 case PW_COA_REQUEST:
1782 memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1785 case PW_AUTHENTICATION_ACK:
1786 case PW_AUTHENTICATION_REJECT:
1787 case PW_ACCESS_CHALLENGE:
1789 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1792 memcpy(hdr->vector, original->vector,
1796 default: /* others have vector already set to zero */
1802 * Set the authentication vector to zero,
1803 * calculate the signature, and put it
1804 * into the Message-Authenticator
1807 fr_hmac_md5(packet->data, packet->data_len,
1808 (const uint8_t *) secret, strlen(secret),
1810 memcpy(packet->data + packet->offset + 2,
1811 calc_auth_vector, AUTH_VECTOR_LEN);
1814 * Copy the original request vector back
1815 * to the raw packet.
1817 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1821 * Switch over the packet code, deciding how to
1824 switch (packet->code) {
1826 * Request packets are not signed, bur
1827 * have a random authentication vector.
1829 case PW_AUTHENTICATION_REQUEST:
1830 case PW_STATUS_SERVER:
1834 * Reply packets are signed with the
1835 * authentication vector of the request.
1842 fr_MD5Init(&context);
1843 fr_MD5Update(&context, packet->data, packet->data_len);
1844 fr_MD5Update(&context, (const uint8_t *) secret,
1846 fr_MD5Final(digest, &context);
1848 memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1849 memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1852 }/* switch over packet codes */
1858 * Reply to the request. Also attach
1859 * reply attribute value pairs and any user message provided.
1861 int rad_send(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1866 char ip_buffer[128];
1869 * Maybe it's a fake packet. Don't send it.
1871 if (!packet || (packet->sockfd < 0)) {
1875 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1876 what = fr_packet_codes[packet->code];
1882 * First time through, allocate room for the packet
1884 if (!packet->data) {
1886 * Encode the packet.
1888 if (rad_encode(packet, original, secret) < 0) {
1893 * Re-sign it, including updating the
1894 * Message-Authenticator.
1896 if (rad_sign(packet, original, secret) < 0) {
1901 * If packet->data points to data, then we print out
1902 * the VP list again only for debugging.
1904 } else if (fr_debug_flag) {
1905 DEBUG("Sending %s of id %d to %s port %d\n", what, packet->id,
1906 inet_ntop(packet->dst_ipaddr.af,
1907 &packet->dst_ipaddr.ipaddr,
1908 ip_buffer, sizeof(ip_buffer)),
1911 for (reply = packet->vps; reply; reply = reply->next) {
1912 if ((reply->vendor == 0) &&
1913 ((reply->attribute & 0xFFFF) > 0xff)) continue;
1919 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
1923 * And send it on it's way.
1925 return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
1926 &packet->src_ipaddr, packet->src_port,
1927 &packet->dst_ipaddr, packet->dst_port);
1931 * Do a comparison of two authentication digests by comparing
1932 * the FULL digest. Otehrwise, the server can be subject to
1933 * timing attacks that allow attackers find a valid message
1936 * http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
1938 int rad_digest_cmp(const uint8_t *a, const uint8_t *b, size_t length)
1943 for (i = 0; i < length; i++) {
1944 result |= a[i] ^ b[i];
1947 return result; /* 0 is OK, !0 is !OK, just like memcmp */
1952 * Validates the requesting client NAS. Calculates the
1953 * signature based on the clients private key.
1955 static int calc_acctdigest(RADIUS_PACKET *packet, const char *secret)
1957 uint8_t digest[AUTH_VECTOR_LEN];
1961 * Zero out the auth_vector in the received packet.
1962 * Then append the shared secret to the received packet,
1963 * and calculate the MD5 sum. This must be the same
1964 * as the original MD5 sum (packet->vector).
1966 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1969 * MD5(packet + secret);
1971 fr_MD5Init(&context);
1972 fr_MD5Update(&context, packet->data, packet->data_len);
1973 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1974 fr_MD5Final(digest, &context);
1977 * Return 0 if OK, 2 if not OK.
1979 if (rad_digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
1985 * Validates the requesting client NAS. Calculates the
1986 * signature based on the clients private key.
1988 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1991 uint8_t calc_digest[AUTH_VECTOR_LEN];
1997 if (original == NULL) {
2002 * Copy the original vector in place.
2004 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2007 * MD5(packet + secret);
2009 fr_MD5Init(&context);
2010 fr_MD5Update(&context, packet->data, packet->data_len);
2011 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
2012 fr_MD5Final(calc_digest, &context);
2015 * Copy the packet's vector back to the packet.
2017 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2020 * Return 0 if OK, 2 if not OK.
2022 if (rad_digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
2028 * Check if a set of RADIUS formatted TLVs are OK.
2030 int rad_tlv_ok(const uint8_t *data, size_t length,
2031 size_t dv_type, size_t dv_length)
2033 const uint8_t *end = data + length;
2035 if ((dv_length > 2) || (dv_type == 0) || (dv_type > 4)) {
2036 fr_strerror_printf("rad_tlv_ok: Invalid arguments");
2040 while (data < end) {
2043 if ((data + dv_type + dv_length) > end) {
2044 fr_strerror_printf("Attribute header overflow");
2050 if ((data[0] == 0) && (data[1] == 0) &&
2051 (data[2] == 0) && (data[3] == 0)) {
2053 fr_strerror_printf("Invalid attribute 0");
2058 fr_strerror_printf("Invalid attribute > 2^24");
2064 if ((data[1] == 0) && (data[1] == 0)) goto zero;
2068 if (data[0] == 0) goto zero;
2072 fr_strerror_printf("Internal sanity check failed");
2076 switch (dv_length) {
2081 if (data[dv_type + 1] != 0) {
2082 fr_strerror_printf("Attribute is longer than 256 octets");
2087 attrlen = data[dv_type + dv_length - 1];
2092 fr_strerror_printf("Internal sanity check failed");
2096 if (attrlen < (dv_type + dv_length)) {
2097 fr_strerror_printf("Attribute header has invalid length");
2101 if (attrlen > length) {
2102 fr_strerror_printf("Attribute overflows container");
2115 * See if the data pointed to by PTR is a valid RADIUS packet.
2117 * packet is not 'const * const' because we may update data_len,
2118 * if there's more data in the UDP packet than in the RADIUS packet.
2120 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
2125 radius_packet_t *hdr;
2126 char host_ipaddr[128];
2132 * Check for packets smaller than the packet header.
2134 * RFC 2865, Section 3., subsection 'length' says:
2136 * "The minimum length is 20 ..."
2138 if (packet->data_len < AUTH_HDR_LEN) {
2139 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %d < minimum %d)",
2140 inet_ntop(packet->src_ipaddr.af,
2141 &packet->src_ipaddr.ipaddr,
2142 host_ipaddr, sizeof(host_ipaddr)),
2143 (int) packet->data_len, AUTH_HDR_LEN);
2148 * RFC 2865, Section 3., subsection 'length' says:
2150 * " ... and maximum length is 4096."
2152 if (packet->data_len > MAX_PACKET_LEN) {
2153 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (received %d > maximum %d)",
2154 inet_ntop(packet->src_ipaddr.af,
2155 &packet->src_ipaddr.ipaddr,
2156 host_ipaddr, sizeof(host_ipaddr)),
2157 (int) packet->data_len, MAX_PACKET_LEN);
2162 * Check for packets with mismatched size.
2163 * i.e. We've received 128 bytes, and the packet header
2164 * says it's 256 bytes long.
2166 totallen = (packet->data[2] << 8) | packet->data[3];
2167 hdr = (radius_packet_t *)packet->data;
2170 * Code of 0 is not understood.
2171 * Code of 16 or greate is not understood.
2173 if ((hdr->code == 0) ||
2174 (hdr->code >= FR_MAX_PACKET_CODE)) {
2175 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code%d ",
2176 inet_ntop(packet->src_ipaddr.af,
2177 &packet->src_ipaddr.ipaddr,
2178 host_ipaddr, sizeof(host_ipaddr)),
2184 * Message-Authenticator is required in Status-Server
2185 * packets, otherwise they can be trivially forged.
2187 if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
2190 * It's also required if the caller asks for it.
2192 if (flags) require_ma = 1;
2195 * Repeat the length checks. This time, instead of
2196 * looking at the data we received, look at the value
2197 * of the 'length' field inside of the packet.
2199 * Check for packets smaller than the packet header.
2201 * RFC 2865, Section 3., subsection 'length' says:
2203 * "The minimum length is 20 ..."
2205 if (totallen < AUTH_HDR_LEN) {
2206 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %d < minimum %d)",
2207 inet_ntop(packet->src_ipaddr.af,
2208 &packet->src_ipaddr.ipaddr,
2209 host_ipaddr, sizeof(host_ipaddr)),
2210 totallen, AUTH_HDR_LEN);
2215 * And again, for the value of the 'length' field.
2217 * RFC 2865, Section 3., subsection 'length' says:
2219 * " ... and maximum length is 4096."
2221 if (totallen > MAX_PACKET_LEN) {
2222 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (length %d > maximum %d)",
2223 inet_ntop(packet->src_ipaddr.af,
2224 &packet->src_ipaddr.ipaddr,
2225 host_ipaddr, sizeof(host_ipaddr)),
2226 totallen, MAX_PACKET_LEN);
2231 * RFC 2865, Section 3., subsection 'length' says:
2233 * "If the packet is shorter than the Length field
2234 * indicates, it MUST be silently discarded."
2236 * i.e. No response to the NAS.
2238 if (packet->data_len < totallen) {
2239 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %d octets, packet length says %d",
2240 inet_ntop(packet->src_ipaddr.af,
2241 &packet->src_ipaddr.ipaddr,
2242 host_ipaddr, sizeof(host_ipaddr)),
2243 (int) packet->data_len, totallen);
2248 * RFC 2865, Section 3., subsection 'length' says:
2250 * "Octets outside the range of the Length field MUST be
2251 * treated as padding and ignored on reception."
2253 if (packet->data_len > totallen) {
2255 * We're shortening the packet below, but just
2256 * to be paranoid, zero out the extra data.
2258 memset(packet->data + totallen, 0, packet->data_len - totallen);
2259 packet->data_len = totallen;
2263 * Walk through the packet's attributes, ensuring that
2264 * they add up EXACTLY to the size of the packet.
2266 * If they don't, then the attributes either under-fill
2267 * or over-fill the packet. Any parsing of the packet
2268 * is impossible, and will result in unknown side effects.
2270 * This would ONLY happen with buggy RADIUS implementations,
2271 * or with an intentional attack. Either way, we do NOT want
2272 * to be vulnerable to this problem.
2275 count = totallen - AUTH_HDR_LEN;
2280 * We need at least 2 bytes to check the
2284 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute header overflows the packet",
2285 inet_ntop(packet->src_ipaddr.af,
2286 &packet->src_ipaddr.ipaddr,
2287 host_ipaddr, sizeof(host_ipaddr)));
2292 * Attribute number zero is NOT defined.
2295 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
2296 inet_ntop(packet->src_ipaddr.af,
2297 &packet->src_ipaddr.ipaddr,
2298 host_ipaddr, sizeof(host_ipaddr)));
2303 * Attributes are at LEAST as long as the ID & length
2304 * fields. Anything shorter is an invalid attribute.
2307 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u too short",
2308 inet_ntop(packet->src_ipaddr.af,
2309 &packet->src_ipaddr.ipaddr,
2310 host_ipaddr, sizeof(host_ipaddr)),
2316 * If there are fewer bytes in the packet than in the
2317 * attribute, it's a bad packet.
2319 if (count < attr[1]) {
2320 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u data overflows the packet",
2321 inet_ntop(packet->src_ipaddr.af,
2322 &packet->src_ipaddr.ipaddr,
2323 host_ipaddr, sizeof(host_ipaddr)),
2329 * Sanity check the attributes for length.
2332 default: /* don't do anything by default */
2336 * If there's an EAP-Message, we require
2337 * a Message-Authenticator.
2339 case PW_EAP_MESSAGE:
2343 case PW_MESSAGE_AUTHENTICATOR:
2344 if (attr[1] != 2 + AUTH_VECTOR_LEN) {
2345 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
2346 inet_ntop(packet->src_ipaddr.af,
2347 &packet->src_ipaddr.ipaddr,
2348 host_ipaddr, sizeof(host_ipaddr)),
2357 * FIXME: Look up the base 255 attributes in the
2358 * dictionary, and switch over their type. For
2359 * integer/date/ip, the attribute length SHOULD
2362 count -= attr[1]; /* grab the attribute length */
2364 num_attributes++; /* seen one more attribute */
2368 * If the attributes add up to a packet, it's allowed.
2370 * If not, we complain, and throw the packet away.
2373 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
2374 inet_ntop(packet->src_ipaddr.af,
2375 &packet->src_ipaddr.ipaddr,
2376 host_ipaddr, sizeof(host_ipaddr)));
2381 * If we're configured to look for a maximum number of
2382 * attributes, and we've seen more than that maximum,
2383 * then throw the packet away, as a possible DoS.
2385 if ((fr_max_attributes > 0) &&
2386 (num_attributes > fr_max_attributes)) {
2387 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2388 inet_ntop(packet->src_ipaddr.af,
2389 &packet->src_ipaddr.ipaddr,
2390 host_ipaddr, sizeof(host_ipaddr)),
2391 num_attributes, fr_max_attributes);
2396 * http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
2398 * A packet with an EAP-Message attribute MUST also have
2399 * a Message-Authenticator attribute.
2401 * A Message-Authenticator all by itself is OK, though.
2403 * Similarly, Status-Server packets MUST contain
2404 * Message-Authenticator attributes.
2406 if (require_ma && ! seen_ma) {
2407 fr_strerror_printf("WARNING: Insecure packet from host %s: Packet does not contain required Message-Authenticator attribute",
2408 inet_ntop(packet->src_ipaddr.af,
2409 &packet->src_ipaddr.ipaddr,
2410 host_ipaddr, sizeof(host_ipaddr)));
2415 * Fill RADIUS header fields
2417 packet->code = hdr->code;
2418 packet->id = hdr->id;
2419 memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
2426 * Receive UDP client requests, and fill in
2427 * the basics of a RADIUS_PACKET structure.
2429 RADIUS_PACKET *rad_recv(int fd, int flags)
2432 RADIUS_PACKET *packet;
2435 * Allocate the new request data structure
2437 if ((packet = malloc(sizeof(*packet))) == NULL) {
2438 fr_strerror_printf("out of memory");
2441 memset(packet, 0, sizeof(*packet));
2444 sock_flags = MSG_PEEK;
2448 packet->data_len = rad_recvfrom(fd, &packet->data, sock_flags,
2449 &packet->src_ipaddr, &packet->src_port,
2450 &packet->dst_ipaddr, &packet->dst_port);
2453 * Check for socket errors.
2455 if (packet->data_len < 0) {
2456 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
2457 /* packet->data is NULL */
2463 * If the packet is too big, then rad_recvfrom did NOT
2464 * allocate memory. Instead, it just discarded the
2467 if (packet->data_len > MAX_PACKET_LEN) {
2468 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
2469 /* packet->data is NULL */
2475 * Read no data. Continue.
2476 * This check is AFTER the MAX_PACKET_LEN check above, because
2477 * if the packet is larger than MAX_PACKET_LEN, we also have
2478 * packet->data == NULL
2480 if ((packet->data_len == 0) || !packet->data) {
2481 fr_strerror_printf("Empty packet: Socket is not ready.");
2487 * See if it's a well-formed RADIUS packet.
2489 if (!rad_packet_ok(packet, flags)) {
2495 * Remember which socket we read the packet from.
2497 packet->sockfd = fd;
2500 * FIXME: Do even more filtering by only permitting
2501 * certain IP's. The problem is that we don't know
2502 * how to do this properly for all possible clients...
2506 * Explicitely set the VP list to empty.
2510 if (fr_debug_flag) {
2511 char host_ipaddr[128];
2513 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2514 DEBUG("rad_recv: %s packet from host %s port %d",
2515 fr_packet_codes[packet->code],
2516 inet_ntop(packet->src_ipaddr.af,
2517 &packet->src_ipaddr.ipaddr,
2518 host_ipaddr, sizeof(host_ipaddr)),
2521 DEBUG("rad_recv: Packet from host %s port %d code=%d",
2522 inet_ntop(packet->src_ipaddr.af,
2523 &packet->src_ipaddr.ipaddr,
2524 host_ipaddr, sizeof(host_ipaddr)),
2528 DEBUG(", id=%d, length=%d\n",
2529 packet->id, (int) packet->data_len);
2533 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2541 * Verify the signature of a packet.
2543 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2550 if (!packet || !packet->data) return -1;
2553 * Before we allocate memory for the attributes, do more
2556 ptr = packet->data + AUTH_HDR_LEN;
2557 length = packet->data_len - AUTH_HDR_LEN;
2558 while (length > 0) {
2559 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
2560 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
2565 default: /* don't do anything. */
2569 * Note that more than one Message-Authenticator
2570 * attribute is invalid.
2572 case PW_MESSAGE_AUTHENTICATOR:
2573 memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
2574 memset(&ptr[2], 0, AUTH_VECTOR_LEN);
2576 switch (packet->code) {
2580 case PW_ACCOUNTING_REQUEST:
2581 case PW_ACCOUNTING_RESPONSE:
2582 case PW_DISCONNECT_REQUEST:
2583 case PW_DISCONNECT_ACK:
2584 case PW_DISCONNECT_NAK:
2585 case PW_COA_REQUEST:
2588 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2591 case PW_AUTHENTICATION_ACK:
2592 case PW_AUTHENTICATION_REJECT:
2593 case PW_ACCESS_CHALLENGE:
2595 fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2598 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2602 fr_hmac_md5(packet->data, packet->data_len,
2603 (const uint8_t *) secret, strlen(secret),
2605 if (rad_digest_cmp(calc_auth_vector, msg_auth_vector,
2606 sizeof(calc_auth_vector)) != 0) {
2608 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator! (Shared secret is incorrect.)",
2609 inet_ntop(packet->src_ipaddr.af,
2610 &packet->src_ipaddr.ipaddr,
2611 buffer, sizeof(buffer)));
2612 /* Silently drop packet, according to RFC 3579 */
2614 } /* else the message authenticator was good */
2617 * Reinitialize Authenticators.
2619 memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2620 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2622 } /* switch over the attributes */
2626 } /* loop over the packet, sanity checking the attributes */
2629 * It looks like a RADIUS packet, but we can't validate
2632 if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2634 fr_strerror_printf("Received Unknown packet code %d "
2635 "from client %s port %d: Cannot validate signature.",
2637 inet_ntop(packet->src_ipaddr.af,
2638 &packet->src_ipaddr.ipaddr,
2639 buffer, sizeof(buffer)),
2645 * Calculate and/or verify digest.
2647 switch(packet->code) {
2651 case PW_AUTHENTICATION_REQUEST:
2652 case PW_STATUS_SERVER:
2654 * The authentication vector is random
2655 * nonsense, invented by the client.
2659 case PW_COA_REQUEST:
2660 case PW_DISCONNECT_REQUEST:
2661 case PW_ACCOUNTING_REQUEST:
2662 if (calc_acctdigest(packet, secret) > 1) {
2663 fr_strerror_printf("Received %s packet "
2664 "from client %s with invalid signature! (Shared secret is incorrect.)",
2665 fr_packet_codes[packet->code],
2666 inet_ntop(packet->src_ipaddr.af,
2667 &packet->src_ipaddr.ipaddr,
2668 buffer, sizeof(buffer)));
2673 /* Verify the reply digest */
2674 case PW_AUTHENTICATION_ACK:
2675 case PW_AUTHENTICATION_REJECT:
2676 case PW_ACCESS_CHALLENGE:
2677 case PW_ACCOUNTING_RESPONSE:
2678 case PW_DISCONNECT_ACK:
2679 case PW_DISCONNECT_NAK:
2682 rcode = calc_replydigest(packet, original, secret);
2684 fr_strerror_printf("Received %s packet "
2685 "from home server %s port %d with invalid signature! (Shared secret is incorrect.)",
2686 fr_packet_codes[packet->code],
2687 inet_ntop(packet->src_ipaddr.af,
2688 &packet->src_ipaddr.ipaddr,
2689 buffer, sizeof(buffer)),
2696 fr_strerror_printf("Received Unknown packet code %d "
2697 "from client %s port %d: Cannot validate signature",
2699 inet_ntop(packet->src_ipaddr.af,
2700 &packet->src_ipaddr.ipaddr,
2701 buffer, sizeof(buffer)),
2711 * Create a "raw" attribute from the attribute contents.
2713 static ssize_t data2vp_raw(UNUSED const RADIUS_PACKET *packet,
2714 UNUSED const RADIUS_PACKET *original,
2715 UNUSED const char *secret,
2716 unsigned int attribute, unsigned int vendor,
2717 const uint8_t *data, size_t length,
2723 * Keep the next function happy.
2725 vp = pairalloc(NULL);
2726 vp = paircreate_raw(attribute, vendor, PW_TYPE_OCTETS, vp);
2728 fr_strerror_printf("data2vp_raw: Failed creating attribute");
2732 vp->length = length;
2735 * If the data is too large, mark it as a "TLV".
2737 if (length <= sizeof(vp->vp_octets)) {
2738 memcpy(vp->vp_octets, data, length);
2740 vp->type = PW_TYPE_TLV;
2741 vp->vp_tlv = malloc(length);
2746 memcpy(vp->vp_tlv, data, length);
2755 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
2756 const RADIUS_PACKET *original,
2758 unsigned int attribute, unsigned int vendor,
2760 const uint8_t *start, size_t length,
2764 * Create any kind of VP from the attribute contents.
2766 * Will return -1 on error, or "length".
2768 static ssize_t data2vp_any(const RADIUS_PACKET *packet,
2769 const RADIUS_PACKET *original,
2770 const char *secret, int nest,
2771 unsigned int attribute, unsigned int vendor,
2772 const uint8_t *data, size_t length,
2775 int data_offset = 0;
2777 VALUE_PAIR *vp = NULL;
2781 * Hacks for CUI. The WiMAX spec says that it
2782 * can be zero length, even though this is
2783 * forbidden by the RADIUS specs. So... we make
2784 * a special case for it.
2786 if ((vendor == 0) &&
2787 (attribute == PW_CHARGEABLE_USER_IDENTITY)) {
2788 data = (const uint8_t *) "";
2796 da = dict_attrbyvalue(attribute, vendor);
2799 * Unknown attribute. Create it as a "raw" attribute.
2802 VP_TRACE("Not found %u.%u\n", vendor, attribute);
2804 if (vp) pairfree(&vp);
2805 return data2vp_raw(packet, original, secret,
2806 attribute, vendor, data, length, pvp);
2810 * TLVs are handled first. They can't be tagged, and
2811 * they can't be encrypted.
2813 if (da->type == PW_TYPE_TLV) {
2814 VP_TRACE("Found TLV %u.%u\n", vendor, attribute);
2815 return data2vp_tlvs(packet, original, secret,
2816 attribute, vendor, nest,
2821 * The attribute is known, and well formed. We can now
2822 * create it. The main failure from here on in is being
2831 if (vp->flags.has_tag) {
2832 if (TAG_VALID(data[0]) ||
2833 (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD)) {
2835 * Tunnel passwords REQUIRE a tag, even
2836 * if don't have a valid tag.
2838 vp->flags.tag = data[0];
2840 if ((vp->type == PW_TYPE_STRING) ||
2841 (vp->type == PW_TYPE_OCTETS)) {
2842 if (length == 0) goto raw;
2849 * Copy the data to be decrypted
2851 vp->length = length - data_offset;
2852 memcpy(&vp->vp_octets[0], data + data_offset, vp->length);
2855 * Decrypt the attribute.
2857 switch (vp->flags.encrypt) {
2861 case FLAG_ENCRYPT_USER_PASSWORD:
2863 rad_pwdecode(vp->vp_strvalue,
2867 rad_pwdecode(vp->vp_strvalue,
2871 if (vp->attribute == PW_USER_PASSWORD) {
2872 vp->length = strlen(vp->vp_strvalue);
2877 * Tunnel-Password's may go ONLY
2878 * in response packets.
2880 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
2881 if (!original) goto raw;
2883 if (rad_tunnel_pwdecode(vp->vp_octets, &vp->length,
2884 secret, original->vector) < 0) {
2890 * Ascend-Send-Secret
2891 * Ascend-Receive-Secret
2893 case FLAG_ENCRYPT_ASCEND_SECRET:
2897 uint8_t my_digest[AUTH_VECTOR_LEN];
2898 make_secret(my_digest,
2901 memcpy(vp->vp_strvalue, my_digest,
2903 vp->vp_strvalue[AUTH_VECTOR_LEN] = '\0';
2904 vp->length = strlen(vp->vp_strvalue);
2910 } /* switch over encryption flags */
2914 case PW_TYPE_STRING:
2915 case PW_TYPE_OCTETS:
2916 case PW_TYPE_ABINARY:
2917 /* nothing more to do */
2921 if (vp->length != 1) goto raw;
2923 vp->vp_integer = vp->vp_octets[0];
2928 if (vp->length != 2) goto raw;
2930 vp->vp_integer = (vp->vp_octets[0] << 8) | vp->vp_octets[1];
2933 case PW_TYPE_INTEGER:
2934 if (vp->length != 4) goto raw;
2936 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2937 vp->vp_integer = ntohl(vp->vp_integer);
2939 if (vp->flags.has_tag) vp->vp_integer &= 0x00ffffff;
2942 * Try to get named VALUEs
2946 dval = dict_valbyattr(vp->attribute, vp->vendor,
2949 strlcpy(vp->vp_strvalue,
2951 sizeof(vp->vp_strvalue));
2957 if (vp->length != 4) goto raw;
2959 memcpy(&vp->vp_date, vp->vp_octets, 4);
2960 vp->vp_date = ntohl(vp->vp_date);
2964 case PW_TYPE_IPADDR:
2965 if (vp->length != 4) goto raw;
2967 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2971 * IPv6 interface ID is 8 octets long.
2974 if (vp->length != 8) goto raw;
2975 /* vp->vp_ifid == vp->vp_octets */
2979 * IPv6 addresses are 16 octets long
2981 case PW_TYPE_IPV6ADDR:
2982 if (vp->length != 16) goto raw;
2983 /* vp->vp_ipv6addr == vp->vp_octets */
2987 * IPv6 prefixes are 2 to 18 octets long.
2989 * RFC 3162: The first octet is unused.
2990 * The second is the length of the prefix
2991 * the rest are the prefix data.
2993 * The prefix length can have value 0 to 128.
2995 case PW_TYPE_IPV6PREFIX:
2996 if (vp->length < 2 || vp->length > 18) goto raw;
2997 if (vp->vp_octets[1] > 128) goto raw;
3000 * FIXME: double-check that
3001 * (vp->vp_octets[1] >> 3) matches vp->length + 2
3003 if (vp->length < 18) {
3004 memset(vp->vp_octets + vp->length, 0,
3009 case PW_TYPE_SIGNED:
3010 if (vp->length != 4) goto raw;
3013 * Overload vp_integer for ntohl, which takes
3014 * uint32_t, not int32_t
3016 memcpy(&vp->vp_integer, vp->vp_octets, 4);
3017 vp->vp_integer = ntohl(vp->vp_integer);
3018 memcpy(&vp->vp_signed, &vp->vp_integer, 4);
3023 fr_strerror_printf("data2vp_any: Internal sanity check failed");
3026 case PW_TYPE_COMBO_IP:
3027 if (vp->length == 4) {
3028 vp->type = PW_TYPE_IPADDR;
3029 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
3032 } else if (vp->length == 16) {
3033 vp->type = PW_TYPE_IPV6ADDR;
3034 /* vp->vp_ipv6addr == vp->vp_octets */
3051 * Convert a top-level VSA to a VP.
3053 static ssize_t attr2vp_vsa(const RADIUS_PACKET *packet,
3054 const RADIUS_PACKET *original,
3055 const char *secret, unsigned int vendor,
3056 size_t dv_type, size_t dv_length,
3057 const uint8_t *data, size_t length,
3060 unsigned int attribute;
3061 ssize_t attrlen, my_len;
3064 if (length <= (dv_type + dv_length)) {
3065 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3072 /* data[0] must be zero */
3073 attribute = data[1] << 16;
3074 attribute |= data[2] << 8;
3075 attribute |= data[3];
3079 attribute = data[0] << 8;
3080 attribute |= data[1];
3084 attribute = data[0];
3088 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3092 switch (dv_length) {
3094 /* data[dv_type] must be zero */
3095 attrlen = data[dv_type + 1];
3099 attrlen = data[dv_type];
3107 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3112 if (attrlen <= (ssize_t) (dv_type + dv_length)) {
3113 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3118 attrlen -= (dv_type + dv_length);
3120 my_len = data2vp_any(packet, original, secret, 0,
3122 data + dv_type + dv_length, attrlen, pvp);
3123 if (my_len < 0) return my_len;
3126 if (my_len != attrlen) {
3128 fr_strerror_printf("attr2vp_vsa: Incomplete decode %d != %d",
3129 (int) my_len, (int) attrlen);
3134 return dv_type + dv_length + attrlen;
3138 * Convert one or more TLVs to VALUE_PAIRs. This function can
3139 * be called recursively...
3141 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
3142 const RADIUS_PACKET *original,
3144 unsigned int attribute, unsigned int vendor,
3146 const uint8_t *start, size_t length,
3149 size_t dv_type, dv_length;
3150 const uint8_t *data, *end;
3151 VALUE_PAIR *head, **last, *vp;
3156 * The default format for a VSA is the RFC recommended
3163 * Top-level TLVs can be of a weird format. TLVs
3164 * encapsulated in a TLV can only be in the RFC format.
3168 dv = dict_vendorbyvalue(vendor);
3171 dv_length = dv->length;
3172 /* dict.c enforces sane values on the above fields */
3176 if (nest >= fr_attr_max_tlv) {
3177 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in recursion");
3182 * The VSAs do not exactly fill the data,
3183 * The *entire* TLV is malformed.
3185 if (rad_tlv_ok(data, length, dv_type, dv_length) < 0) {
3186 VP_TRACE("TLV malformed %u.%u\n", vendor, attribute);
3187 return data2vp_raw(packet, original, secret,
3188 attribute, vendor, data, length, pvp);
3191 end = data + length;
3195 while (data < end) {
3196 unsigned int my_attr;
3197 unsigned int my_len;
3200 if ((data + dv_type + dv_length) > end) {
3201 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: Insufficient data");
3209 my_attr = attribute;
3210 my_attr |= ((data[0] & fr_attr_mask[nest + 1])
3211 << fr_attr_shift[nest + 1]);
3214 my_attr = (data[0] << 8) | data[1];
3218 my_attr = (data[1] << 16) | (data[1] << 8) | data[3];
3222 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3226 switch (dv_length) {
3233 my_len = data[dv_type + dv_length - 1];
3237 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3242 if (my_len < (dv_type + dv_length)) {
3243 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: underflow");
3248 if ((data + my_len) > end) {
3249 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: overflow");
3255 my_len -= dv_type + dv_length;
3258 * If this returns > 0, it returns "my_len"
3260 if (data2vp_any(packet, original, secret, nest + 1,
3262 data + dv_type + dv_length, my_len, &vp) < 0) {
3267 data += my_len + dv_type + dv_length;
3277 return data - start;
3282 * Group "continued" attributes together, and create VPs from them.
3283 * The caller ensures that the RADIUS packet is OK, and that the
3284 * continuations have all been checked.
3286 static ssize_t data2vp_continued(const RADIUS_PACKET *packet,
3287 const RADIUS_PACKET *original,
3289 const uint8_t *start, size_t length,
3290 VALUE_PAIR **pvp, int nest,
3291 unsigned int attribute, unsigned int vendor,
3292 int first_offset, int later_offset,
3296 uint8_t *attr, *ptr;
3297 const uint8_t *data;
3299 attr = malloc(attrlen);
3301 fr_strerror_printf("Out of memory");
3312 memcpy(ptr, data + first_offset, data[1] - first_offset);
3313 ptr += data[1] - first_offset;
3314 left -= data[1] - first_offset;
3319 if (data >= (start + length)) {
3320 fr_strerror_printf("data2vp_continued: Internal sanity check failed");
3324 memcpy(ptr, data + later_offset, data[1] - later_offset);
3325 ptr += data[1] - later_offset;
3326 left -= data[1] - later_offset;
3330 left = data2vp_any(packet, original, secret, nest,
3332 attr, attrlen, pvp);
3334 if (left < 0) return left;
3336 return data - start;
3341 * Create a "raw" VALUE_PAIR from a RADIUS attribute.
3343 ssize_t rad_attr2vp_raw(const RADIUS_PACKET *packet,
3344 const RADIUS_PACKET *original,
3346 const uint8_t *data, size_t length,
3351 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3352 fr_strerror_printf("rad_attr2vp_raw: Invalid length");
3356 my_len = data2vp_raw(packet, original, secret, data[0], 0,
3357 data + 2, data[1] - 2, pvp);
3358 if (my_len < 0) return my_len;
3365 * Get the length of the data portion of all of the contiguous
3366 * continued attributes.
3368 * 0 for "no continuation"
3369 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3371 static ssize_t wimax_attrlen(uint32_t vendor,
3372 const uint8_t *start, const uint8_t *end)
3375 const uint8_t *data = start;
3377 if ((data[8] & 0x80) == 0) return 0;
3378 total = data[7] - 3;
3381 while (data < end) {
3383 if ((data + 9) > end) return -1;
3385 if ((data[0] != PW_VENDOR_SPECIFIC) ||
3387 (memcmp(data + 2, &vendor, 4) != 0) ||
3388 (data[6] != start[6]) ||
3389 ((data[7] + 6) != data[1])) return -1;
3391 total += data[7] - 3;
3392 if ((data[8] & 0x80) == 0) break;
3401 * Get the length of the data portion of all of the contiguous
3402 * continued attributes.
3404 * 0 for "no continuation"
3405 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3407 static ssize_t extended_attrlen(const uint8_t *start, const uint8_t *end)
3410 const uint8_t *data = start;
3412 if ((data[3] & 0x80) == 0) return 0;
3413 total = data[1] - 4;
3416 while (data < end) {
3417 if ((data + 4) > end) return -1;
3419 if ((data[0] != start[0]) ||
3421 (data[2] != start[2])) return -1;
3423 total += data[1] - 4;
3424 if ((data[3] & 0x80) == 0) break;
3433 * Create WiMAX VALUE_PAIRs from a RADIUS attribute.
3435 ssize_t rad_attr2vp_wimax(const RADIUS_PACKET *packet,
3436 const RADIUS_PACKET *original,
3438 const uint8_t *data, size_t length,
3442 unsigned int attribute;
3445 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3446 fr_strerror_printf("rad_attr2vp_wimax: Invalid length");
3450 if (data[0] != PW_VENDOR_SPECIFIC) {
3451 fr_strerror_printf("rad_attr2vp_wimax: Invalid attribute");
3456 * Not enough room for a Vendor-Id. + WiMAX header
3459 return rad_attr2vp_raw(packet, original, secret,
3463 memcpy(&lvalue, data + 2, 4);
3464 lvalue = ntohl(lvalue);
3469 if (lvalue != VENDORPEC_WIMAX) {
3472 dv = dict_vendorbyvalue(lvalue);
3473 if (!dv || !dv->flags) {
3474 fr_strerror_printf("rad_attr2vp_wimax: Not a WiMAX attribute");
3480 * The WiMAX attribute is encapsulated in a VSA. If the
3481 * WiMAX length disagrees with the VSA length, it's malformed.
3483 if ((data[7] + 6) != data[1]) {
3484 return rad_attr2vp_raw(packet, original, secret,
3488 attribute = data[6];
3491 * Attribute is continued. Do some more work.
3494 my_len = wimax_attrlen(htonl(lvalue), data, data + length);
3496 return rad_attr2vp_raw(packet, original, secret,
3500 return data2vp_continued(packet, original, secret,
3501 data, length, pvp, 0,
3506 my_len = data2vp_any(packet, original, secret, 0, attribute, lvalue,
3507 data + 9, data[1] - 9, pvp);
3508 if (my_len < 0) return my_len;
3514 * Create Vendor-Specifc VALUE_PAIRs from a RADIUS attribute.
3516 ssize_t rad_attr2vp_vsa(const RADIUS_PACKET *packet,
3517 const RADIUS_PACKET *original,
3519 const uint8_t *data, size_t length,
3522 size_t dv_type, dv_length;
3527 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3528 fr_strerror_printf("rad_attr2vp_vsa: Invalid length");
3532 if (data[0] != PW_VENDOR_SPECIFIC) {
3533 fr_strerror_printf("rad_attr2vp_vsa: Invalid attribute");
3538 * Not enough room for a Vendor-Id.
3539 * Or the high octet of the Vendor-Id is set.
3541 if ((data[1] < 6) || (data[2] != 0)) {
3542 return rad_attr2vp_raw(packet, original, secret,
3546 memcpy(&lvalue, data + 2, 4);
3547 lvalue = ntohl(lvalue);
3550 * WiMAX gets its own set of magic.
3552 if (lvalue == VENDORPEC_WIMAX) {
3554 return rad_attr2vp_wimax(packet, original, secret,
3558 dv_type = dv_length = 1;
3559 dv = dict_vendorbyvalue(lvalue);
3562 dv_length = dv->length;
3564 if (dv->flags) goto wimax;
3568 * Attribute is not in the correct form.
3570 if (rad_tlv_ok(data + 6, data[1] - 6, dv_type, dv_length) < 0) {
3571 return rad_attr2vp_raw(packet, original, secret,
3575 my_len = attr2vp_vsa(packet, original, secret,
3576 lvalue, dv_type, dv_length,
3577 data + 6, data[1] - 6, pvp);
3578 if (my_len < 0) return my_len;
3581 * Incomplete decode means that something is wrong
3582 * with the attribute. Back up, and make it "raw".
3584 if (my_len != (data[1] - 6)) {
3586 return rad_attr2vp_raw(packet, original, secret,
3594 * Create an "extended" VALUE_PAIR from a RADIUS attribute.
3596 ssize_t rad_attr2vp_extended(const RADIUS_PACKET *packet,
3597 const RADIUS_PACKET *original,
3599 const uint8_t *start, size_t length,
3602 unsigned int attribute;
3605 unsigned int vendor = VENDORPEC_EXTENDED;
3606 size_t data_len = length;
3607 const uint8_t *data;
3612 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3613 fr_strerror_printf("rad_attr2vp_extended: Invalid length");
3617 da = dict_attrbyvalue(data[0], vendor);
3619 (!da->flags.extended && !da->flags.extended_flags)) {
3620 fr_strerror_printf("rad_attr2vp_extended: Attribute is not extended format");
3627 * No Extended-Type. It's a raw attribute.
3628 * Also, if there's no data following the Extended-Type,
3629 * it's a raw attribute.
3633 return rad_attr2vp_raw(packet, original, secret, start,
3638 * The attribute is "241.1", for example. Go look that
3639 * up to see what type it is.
3641 attribute = data[0];
3642 attribute |= (data[2] << fr_attr_shift[1]);
3644 da = dict_attrbyvalue(attribute, vendor);
3647 vendor = VENDORPEC_EXTENDED;
3650 if (data[1] < length) data_len = data[1];
3656 * If there's supposed to be a flag octet. If not, it's
3657 * a raw attribute. If the flag is set, it's supposed to
3660 if (da->flags.extended_flags) {
3661 if (data_len == 0) goto raw;
3663 continued = ((data[0] & 0x80) != 0);
3669 * Extended VSAs have 4 octets of
3670 * Vendor-Id followed by one octet of
3673 if (da->flags.evs) {
3674 if (data_len < 5) goto raw;
3677 * Vendor Ids can only be 24-bit.
3679 if (data[0] != 0) goto raw;
3681 vendor = ((data[1] << 16) |
3686 * Pack the *encapsulating* attribute number into
3687 * the vendor id. This number should be >= 241.
3689 vendor |= start[0] * FR_MAX_VENDOR;
3693 * Over-write the attribute with the
3696 attribute = data[4];
3702 int first_offset = 4;
3705 if (vendor != VENDORPEC_EXTENDED) first_offset += 5;
3707 my_len = extended_attrlen(start, start + length);
3708 if (my_len < 0) goto raw;
3710 if (vendor != VENDORPEC_EXTENDED) my_len -= 5;
3712 return data2vp_continued(packet, original, secret,
3713 start, length, pvp, shift,
3715 first_offset, 4, my_len);
3718 if (data2vp_any(packet, original, secret, shift,
3719 attribute, vendor, data, data_len, pvp) < 0) {
3723 return (data + data_len) - start;
3728 * Create a "standard" RFC VALUE_PAIR from the given data.
3730 ssize_t rad_attr2vp_rfc(const RADIUS_PACKET *packet,
3731 const RADIUS_PACKET *original,
3733 const uint8_t *data, size_t length,
3736 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3737 fr_strerror_printf("rad_attr2vp_rfc: Insufficient data");
3741 if (data2vp_any(packet, original, secret, 0,
3742 data[0], 0, data + 2, data[1] - 2, pvp) < 0) {
3750 * Create a "normal" VALUE_PAIR from the given data.
3752 ssize_t rad_attr2vp(const RADIUS_PACKET *packet,
3753 const RADIUS_PACKET *original,
3755 const uint8_t *data, size_t length,
3758 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3759 fr_strerror_printf("rad_attr2vp: Insufficient data");
3764 * VSAs get their own handler.
3766 if (data[0] == PW_VENDOR_SPECIFIC) {
3767 return rad_attr2vp_vsa(packet, original, secret,
3772 * Extended attribute format gets their own handler.
3774 if (dict_attrbyvalue(data[0], VENDORPEC_EXTENDED) != NULL) {
3775 return rad_attr2vp_extended(packet, original, secret,
3779 return rad_attr2vp_rfc(packet, original, secret, data, length, pvp);
3784 * Calculate/check digest, and decode radius attributes.
3786 * -1 on decoding error
3789 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
3795 radius_packet_t *hdr;
3796 VALUE_PAIR *head, **tail, *vp;
3799 * Extract attribute-value pairs
3801 hdr = (radius_packet_t *)packet->data;
3803 packet_length = packet->data_len - AUTH_HDR_LEN;
3810 * Loop over the attributes, decoding them into VPs.
3812 while (packet_length > 0) {
3816 * This may return many VPs
3818 my_len = rad_attr2vp(packet, original, secret,
3819 ptr, packet_length, &vp);
3834 * VSA's may not have been counted properly in
3835 * rad_packet_ok() above, as it is hard to count
3836 * then without using the dictionary. We
3837 * therefore enforce the limits here, too.
3839 if ((fr_max_attributes > 0) &&
3840 (num_attributes > fr_max_attributes)) {
3841 char host_ipaddr[128];
3844 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
3845 inet_ntop(packet->src_ipaddr.af,
3846 &packet->src_ipaddr.ipaddr,
3847 host_ipaddr, sizeof(host_ipaddr)),
3848 num_attributes, fr_max_attributes);
3853 packet_length -= my_len;
3857 * Merge information from the outside world into our
3860 fr_rand_seed(packet->data, AUTH_HDR_LEN);
3863 * There may be VP's already in the packet. Don't
3864 * destroy them. Instead, add the decoded attributes to
3865 * the tail of the list.
3867 for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
3879 * We assume that the passwd buffer passed is big enough.
3880 * RFC2138 says the password is max 128 chars, so the size
3881 * of the passwd buffer must be at least 129 characters.
3882 * Preferably it's just MAX_STRING_LEN.
3884 * int *pwlen is updated to the new length of the encrypted
3885 * password - a multiple of 16 bytes.
3887 int rad_pwencode(char *passwd, size_t *pwlen, const char *secret,
3888 const uint8_t *vector)
3890 FR_MD5_CTX context, old;
3891 uint8_t digest[AUTH_VECTOR_LEN];
3892 int i, n, secretlen;
3896 * RFC maximum is 128 bytes.
3898 * If length is zero, pad it out with zeros.
3900 * If the length isn't aligned to 16 bytes,
3901 * zero out the extra data.
3905 if (len > 128) len = 128;
3908 memset(passwd, 0, AUTH_PASS_LEN);
3909 len = AUTH_PASS_LEN;
3910 } else if ((len % AUTH_PASS_LEN) != 0) {
3911 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3912 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3917 * Use the secret to setup the decryption digest
3919 secretlen = strlen(secret);
3921 fr_MD5Init(&context);
3922 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3923 old = context; /* save intermediate work */
3926 * Encrypt it in place. Don't bother checking
3927 * len, as we've ensured above that it's OK.
3929 for (n = 0; n < len; n += AUTH_PASS_LEN) {
3931 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3932 fr_MD5Final(digest, &context);
3935 fr_MD5Update(&context,
3936 (uint8_t *) passwd + n - AUTH_PASS_LEN,
3938 fr_MD5Final(digest, &context);
3941 for (i = 0; i < AUTH_PASS_LEN; i++) {
3942 passwd[i + n] ^= digest[i];
3952 int rad_pwdecode(char *passwd, size_t pwlen, const char *secret,
3953 const uint8_t *vector)
3955 FR_MD5_CTX context, old;
3956 uint8_t digest[AUTH_VECTOR_LEN];
3958 size_t n, secretlen;
3961 * The RFC's say that the maximum is 128.
3962 * The buffer we're putting it into above is 254, so
3963 * we don't need to do any length checking.
3965 if (pwlen > 128) pwlen = 128;
3970 if (pwlen == 0) goto done;
3973 * Use the secret to setup the decryption digest
3975 secretlen = strlen(secret);
3977 fr_MD5Init(&context);
3978 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3979 old = context; /* save intermediate work */
3982 * The inverse of the code above.
3984 for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3986 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3987 fr_MD5Final(digest, &context);
3990 if (pwlen > AUTH_PASS_LEN) {
3991 fr_MD5Update(&context, (uint8_t *) passwd,
3995 fr_MD5Final(digest, &context);
3998 if (pwlen > (n + AUTH_PASS_LEN)) {
3999 fr_MD5Update(&context, (uint8_t *) passwd + n,
4004 for (i = 0; i < AUTH_PASS_LEN; i++) {
4005 passwd[i + n] ^= digest[i];
4010 passwd[pwlen] = '\0';
4011 return strlen(passwd);
4016 * Encode Tunnel-Password attributes when sending them out on the wire.
4018 * int *pwlen is updated to the new length of the encrypted
4019 * password - a multiple of 16 bytes.
4021 * This is per RFC-2868 which adds a two char SALT to the initial intermediate
4024 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, const char *secret,
4025 const uint8_t *vector)
4027 uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
4028 unsigned char digest[AUTH_VECTOR_LEN];
4030 int i, n, secretlen;
4035 if (len > 127) len = 127;
4038 * Shift the password 3 positions right to place a salt and original
4039 * length, tag will be added automatically on packet send
4041 for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
4045 * save original password length as first password character;
4052 * Generate salt. The RFC's say:
4054 * The high bit of salt[0] must be set, each salt in a
4055 * packet should be unique, and they should be random
4057 * So, we set the high bit, add in a counter, and then
4058 * add in some CSPRNG data. should be OK..
4060 salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
4061 (fr_rand() & 0x07));
4062 salt[1] = fr_rand();
4065 * Padd password to multiple of AUTH_PASS_LEN bytes.
4067 n = len % AUTH_PASS_LEN;
4069 n = AUTH_PASS_LEN - n;
4070 for (; n > 0; n--, len++)
4073 /* set new password length */
4077 * Use the secret to setup the decryption digest
4079 secretlen = strlen(secret);
4080 memcpy(buffer, secret, secretlen);
4082 for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
4084 memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
4085 memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
4086 fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
4088 memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
4089 fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
4092 for (i = 0; i < AUTH_PASS_LEN; i++) {
4093 passwd[i + n2] ^= digest[i];
4101 * Decode Tunnel-Password encrypted attributes.
4103 * Defined in RFC-2868, this uses a two char SALT along with the
4104 * initial intermediate value, to differentiate it from the
4107 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, const char *secret,
4108 const uint8_t *vector)
4110 FR_MD5_CTX context, old;
4111 uint8_t digest[AUTH_VECTOR_LEN];
4113 unsigned i, n, len, reallen;
4118 * We need at least a salt.
4121 fr_strerror_printf("tunnel password is too short");
4126 * There's a salt, but no password. Or, there's a salt
4127 * and a 'data_len' octet. It's wrong, but at least we
4128 * can figure out what it means: the password is empty.
4130 * Note that this means we ignore the 'data_len' field,
4131 * if the attribute length tells us that there's no
4132 * more data. So the 'data_len' field may be wrong,
4141 len -= 2; /* discount the salt */
4144 * Use the secret to setup the decryption digest
4146 secretlen = strlen(secret);
4148 fr_MD5Init(&context);
4149 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
4150 old = context; /* save intermediate work */
4153 * Set up the initial key:
4155 * b(1) = MD5(secret + vector + salt)
4157 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4158 fr_MD5Update(&context, passwd, 2);
4161 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4165 fr_MD5Final(digest, &context);
4170 * A quick check: decrypt the first octet
4171 * of the password, which is the
4172 * 'data_len' field. Ensure it's sane.
4174 reallen = passwd[2] ^ digest[0];
4175 if (reallen >= len) {
4176 fr_strerror_printf("tunnel password is too long for the attribute");
4180 fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
4184 fr_MD5Final(digest, &context);
4187 fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
4190 for (i = base; i < AUTH_PASS_LEN; i++) {
4191 passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
4196 * See make_tunnel_password, above.
4198 if (reallen > 239) reallen = 239;
4201 passwd[reallen] = 0;
4207 * Encode a CHAP password
4209 * FIXME: might not work with Ascend because
4210 * we use vp->length, and Ascend gear likes
4211 * to send an extra '\0' in the string!
4213 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
4214 VALUE_PAIR *password)
4218 uint8_t string[MAX_STRING_LEN * 2 + 1];
4219 VALUE_PAIR *challenge;
4222 * Sanity check the input parameters
4224 if ((packet == NULL) || (password == NULL)) {
4229 * Note that the password VP can be EITHER
4230 * a User-Password attribute (from a check-item list),
4231 * or a CHAP-Password attribute (the client asking
4232 * the library to encode it).
4240 memcpy(ptr, password->vp_strvalue, password->length);
4241 ptr += password->length;
4242 i += password->length;
4245 * Use Chap-Challenge pair if present,
4246 * Request-Authenticator otherwise.
4248 challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0);
4250 memcpy(ptr, challenge->vp_strvalue, challenge->length);
4251 i += challenge->length;
4253 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
4254 i += AUTH_VECTOR_LEN;
4258 fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
4265 * Seed the random number generator.
4267 * May be called any number of times.
4269 void fr_rand_seed(const void *data, size_t size)
4274 * Ensure that the pool is initialized.
4276 if (!fr_rand_initialized) {
4279 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
4281 fd = open("/dev/urandom", O_RDONLY);
4287 while (total < sizeof(fr_rand_pool.randrsl)) {
4288 this = read(fd, fr_rand_pool.randrsl,
4289 sizeof(fr_rand_pool.randrsl) - total);
4290 if ((this < 0) && (errno != EINTR)) break;
4291 if (this > 0) total += this;
4295 fr_rand_pool.randrsl[0] = fd;
4296 fr_rand_pool.randrsl[1] = time(NULL);
4297 fr_rand_pool.randrsl[2] = errno;
4300 fr_randinit(&fr_rand_pool, 1);
4301 fr_rand_pool.randcnt = 0;
4302 fr_rand_initialized = 1;
4308 * Hash the user data
4311 if (!hash) hash = fr_rand();
4312 hash = fr_hash_update(data, size, hash);
4314 fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
4319 * Return a 32-bit random number.
4321 uint32_t fr_rand(void)
4326 * Ensure that the pool is initialized.
4328 if (!fr_rand_initialized) {
4329 fr_rand_seed(NULL, 0);
4332 num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
4333 if (fr_rand_pool.randcnt >= 256) {
4334 fr_rand_pool.randcnt = 0;
4335 fr_isaac(&fr_rand_pool);
4343 * Allocate a new RADIUS_PACKET
4345 RADIUS_PACKET *rad_alloc(int newvector)
4349 if ((rp = malloc(sizeof(RADIUS_PACKET))) == NULL) {
4350 fr_strerror_printf("out of memory");
4353 memset(rp, 0, sizeof(*rp));
4359 uint32_t hash, base;
4362 * Don't expose the actual contents of the random
4366 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
4367 hash = fr_rand() ^ base;
4368 memcpy(rp->vector + i, &hash, sizeof(hash));
4371 fr_rand(); /* stir the pool again */
4376 RADIUS_PACKET *rad_alloc_reply(RADIUS_PACKET *packet)
4378 RADIUS_PACKET *reply;
4380 if (!packet) return NULL;
4382 reply = rad_alloc(0);
4383 if (!reply) return NULL;
4386 * Initialize the fields from the request.
4388 reply->sockfd = packet->sockfd;
4389 reply->dst_ipaddr = packet->src_ipaddr;
4390 reply->src_ipaddr = packet->dst_ipaddr;
4391 reply->dst_port = packet->src_port;
4392 reply->src_port = packet->dst_port;
4393 reply->id = packet->id;
4394 reply->code = 0; /* UNKNOWN code */
4395 memcpy(reply->vector, packet->vector,
4396 sizeof(reply->vector));
4399 reply->data_len = 0;
4406 * Free a RADIUS_PACKET
4408 void rad_free(RADIUS_PACKET **radius_packet_ptr)
4410 RADIUS_PACKET *radius_packet;
4412 if (!radius_packet_ptr || !*radius_packet_ptr) return;
4413 radius_packet = *radius_packet_ptr;
4415 free(radius_packet->data);
4417 pairfree(&radius_packet->vps);
4419 free(radius_packet);
4421 *radius_packet_ptr = NULL;