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, const VALUE_PAIR *next, 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.
698 * Not from the same vendor, skip it.
700 if (vp->vendor != next->vendor) return 0;
703 * In a different TLV space, skip it.
705 tlv1 = vp->attribute;
706 tlv2 = 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;
744 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];
762 if (room > 255) my_room = 255;
764 len = vp2data_any(packet, original, secret, nest,
765 &vp, ptr + 2, my_room - 2);
766 if (len < 0) return len;
767 if (len == 0) return ptr - start;
768 /* len can NEVER be more than 253 */
773 if ((fr_debug_flag > 3) && fr_log_fp) {
774 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
775 print_hex_data(ptr + 2, len, 3);
783 if (!do_next_tlv(svp, vp, nest)) break;
787 if ((fr_debug_flag > 3) && fr_log_fp) {
790 da = dict_attrbyvalue(svp->attribute & ((1 << fr_attr_shift[nest ]) - 1), svp->vendor);
791 if (da) fprintf(fr_log_fp, "\t%s = ...\n", da->name);
800 * Encodes the data portion of an attribute.
801 * Returns -1 on error, or the length of the data portion.
803 static ssize_t vp2data_any(const RADIUS_PACKET *packet,
804 const RADIUS_PACKET *original,
805 const char *secret, int nest,
806 const VALUE_PAIR **pvp,
807 uint8_t *start, size_t room)
812 uint8_t *ptr = start;
814 const VALUE_PAIR *vp = *pvp;
817 * See if we need to encode a TLV. The low portion of
818 * the attribute has already been placed into the packer.
819 * If there are still attribute bytes left, then go
820 * encode them as TLVs.
822 * If we cared about the stack, we could unroll the loop.
824 if (vp->flags.is_tlv && (nest < fr_attr_max_tlv) &&
825 ((vp->attribute >> fr_attr_shift[nest + 1]) != 0)) {
826 return vp2data_tlvs(packet, original, secret, nest + 1, pvp,
833 * Set up the default sources for the data.
835 data = vp->vp_octets;
842 case PW_TYPE_IPV6ADDR:
843 case PW_TYPE_IPV6PREFIX:
844 case PW_TYPE_ABINARY:
845 /* nothing more to do */
849 len = 1; /* just in case */
850 array[0] = vp->vp_integer & 0xff;
855 len = 2; /* just in case */
856 array[0] = (vp->vp_integer >> 8) & 0xff;
857 array[1] = vp->vp_integer & 0xff;
861 case PW_TYPE_INTEGER:
862 len = 4; /* just in case */
863 lvalue = htonl(vp->vp_integer);
864 memcpy(array, &lvalue, sizeof(lvalue));
869 data = (const uint8_t *) &vp->vp_ipaddr;
870 len = 4; /* just in case */
874 * There are no tagged date attributes.
877 lvalue = htonl(vp->vp_date);
878 data = (const uint8_t *) &lvalue;
879 len = 4; /* just in case */
886 len = 4; /* just in case */
887 slvalue = htonl(vp->vp_signed);
888 memcpy(array, &slvalue, sizeof(slvalue));
895 fr_strerror_printf("ERROR: Cannot encode NULL TLV");
901 default: /* unknown type: ignore it */
902 fr_strerror_printf("ERROR: Unknown attribute type %d", vp->type);
915 * Bound the data to the calling size
917 if (len > (ssize_t) room) len = room;
920 * Encrypt the various password styles
922 * Attributes with encrypted values MUST be less than
925 switch (vp->flags.encrypt) {
926 case FLAG_ENCRYPT_USER_PASSWORD:
927 make_passwd(ptr, &len, data, len,
928 secret, packet->vector);
931 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
933 if (vp->flags.has_tag) lvalue = 1;
936 * Check if there's enough room. If there isn't,
937 * we discard the attribute.
939 * This is ONLY a problem if we have multiple VSA's
940 * in one Vendor-Specific, though.
942 if (room < (18 + lvalue)) return 0;
944 switch (packet->code) {
945 case PW_AUTHENTICATION_ACK:
946 case PW_AUTHENTICATION_REJECT:
947 case PW_ACCESS_CHALLENGE:
950 fr_strerror_printf("ERROR: No request packet, cannot encrypt %s attribute in the vp.", vp->name);
954 if (lvalue) ptr[0] = vp->flags.tag;
955 make_tunnel_passwd(ptr + lvalue, &len, data, len,
957 secret, original->vector);
959 case PW_ACCOUNTING_REQUEST:
960 case PW_DISCONNECT_REQUEST:
962 ptr[0] = vp->flags.tag;
963 make_tunnel_passwd(ptr + 1, &len, data, len - 1, room,
964 secret, packet->vector);
970 * The code above ensures that this attribute
973 case FLAG_ENCRYPT_ASCEND_SECRET:
974 make_secret(ptr, packet->vector, secret, data);
975 len = AUTH_VECTOR_LEN;
980 if (vp->flags.has_tag && TAG_VALID(vp->flags.tag)) {
981 if (vp->type == PW_TYPE_STRING) {
982 if (len > ((ssize_t) (room - 1))) len = room - 1;
983 ptr[0] = vp->flags.tag;
985 } else if (vp->type == PW_TYPE_INTEGER) {
986 array[0] = vp->flags.tag;
987 } /* else it can't be any other type */
989 memcpy(ptr, data, len);
991 } /* switch over encryption flags */
994 return len + (ptr - start);
997 static ssize_t attr_shift(const uint8_t *start, const uint8_t *end,
998 uint8_t *ptr, int hdr_len, ssize_t len,
999 int flag_offset, int vsa_offset)
1001 int check_len = len - ptr[1];
1002 int total = len + hdr_len;
1005 * Pass 1: Check if the addition of the headers
1006 * overflows the available room. If so, return
1007 * what we were capable of encoding.
1010 while (check_len > (255 - hdr_len)) {
1012 check_len -= (255 - hdr_len);
1016 * Note that this results in a number of attributes maybe
1017 * being marked as "encoded", but which aren't in the
1018 * packet. Oh well. The solution is to fix the
1019 * "vp2data_any" function to take into account the header
1022 if ((ptr + ptr[1] + total) > end) {
1023 return (ptr + ptr[1]) - start;
1027 * Pass 2: Now that we know there's enough room,
1028 * re-arrange the data to form a set of valid
1029 * RADIUS attributes.
1032 int sublen = 255 - ptr[1];
1034 if (len <= sublen) {
1039 memmove(ptr + 255 + hdr_len, ptr + 255, sublen);
1040 memcpy(ptr + 255, ptr, hdr_len);
1042 if (vsa_offset) ptr[vsa_offset] += sublen;
1043 ptr[flag_offset] |= 0x80;
1047 if (vsa_offset) ptr[vsa_offset] = 3;
1051 if (vsa_offset) ptr[vsa_offset] += len;
1053 return (ptr + ptr[1]) - start;
1058 * Encode an "extended" attribute.
1060 int rad_vp2extended(const RADIUS_PACKET *packet,
1061 const RADIUS_PACKET *original,
1062 const char *secret, const VALUE_PAIR **pvp,
1063 uint8_t *ptr, size_t room)
1068 uint8_t *start = ptr;
1069 const VALUE_PAIR *vp = *pvp;
1071 if (vp->vendor < VENDORPEC_EXTENDED) {
1072 fr_strerror_printf("rad_vp2extended called for non-extended attribute");
1076 if (room < 3) return 0;
1078 ptr[0] = vp->attribute & 0xff;
1081 if (vp->flags.extended) {
1082 ptr[2] = (vp->attribute & 0xff00) >> 8;
1084 } else if (vp->flags.extended_flags) {
1085 if (room < 4) return 0;
1088 ptr[2] = (vp->attribute & 0xff00) >> 8;
1093 * Only "flagged" attributes can be longer than one
1096 if (!vp->flags.extended_flags && (room > 255)) {
1103 if (vp->flags.evs) {
1104 uint8_t *evs = ptr + ptr[1];
1106 if (room < (size_t) (ptr[1] + 5)) return 0;
1109 * RADIUS Attribute Type is packed into the high byte
1110 * of the Vendor Id. So over-write it in the packet.
1112 * And hard-code Extended-Type to Vendor-Specific.
1114 ptr[0] = (vp->vendor >> 24) & 0xff;
1117 evs[0] = 0; /* always zero */
1118 evs[1] = (vp->vendor >> 16) & 0xff;
1119 evs[2] = (vp->vendor >> 8) & 0xff;
1120 evs[3] = vp->vendor & 0xff;
1121 evs[4] = vp->attribute & 0xff;
1128 len = vp2data_any(packet, original, secret, nest,
1129 pvp, ptr + ptr[1], room - hdr_len);
1130 if (len <= 0) return len;
1133 * There may be more than 252 octets of data encoded in
1134 * the attribute. If so, move the data up in the packet,
1135 * and copy the existing header over. Set the "M" flag ONLY
1136 * after copying the rest of the data.
1138 if (vp->flags.extended_flags && (len > (255 - ptr[1]))) {
1139 return attr_shift(start, start + room, ptr, 4, len, 3, 0);
1145 if ((fr_debug_flag > 3) && fr_log_fp) {
1148 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1149 if (!vp->flags.extended_flags) {
1150 fprintf(fr_log_fp, "%02x ", ptr[2]);
1153 fprintf(fr_log_fp, "%02x %02x ", ptr[2], ptr[3]);
1157 if (vp->flags.evs) {
1158 fprintf(fr_log_fp, "%02x%02x%02x%02x (%u) %02x ",
1159 ptr[jump], ptr[jump + 1],
1160 ptr[jump + 2], ptr[jump + 3],
1161 ((ptr[jump + 1] << 16) |
1162 (ptr[jump + 2] << 8) |
1168 print_hex_data(ptr + jump, len, 3);
1172 return (ptr + ptr[1]) - start;
1177 * Encode a WiMAX attribute.
1179 int rad_vp2wimax(const RADIUS_PACKET *packet,
1180 const RADIUS_PACKET *original,
1181 const char *secret, const VALUE_PAIR **pvp,
1182 uint8_t *ptr, size_t room)
1187 uint8_t *start = ptr;
1188 const VALUE_PAIR *vp = *pvp;
1191 * Double-check for WiMAX format.
1193 if (!vp->flags.wimax) {
1194 fr_strerror_printf("rad_vp2wimax called for non-WIMAX VSA");
1199 * Not enough room for:
1200 * attr, len, vendor-id, vsa, vsalen, continuation
1202 if (room < 9) return 0;
1205 * Build the Vendor-Specific header
1208 ptr[0] = PW_VENDOR_SPECIFIC;
1210 lvalue = htonl(vp->vendor);
1211 memcpy(ptr + 2, &lvalue, 4);
1212 ptr[6] = (vp->attribute & fr_attr_mask[1]);
1214 ptr[8] = 0; /* continuation byte */
1218 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1],
1220 if (len <= 0) return len;
1223 * There may be more than 252 octets of data encoded in
1224 * the attribute. If so, move the data up in the packet,
1225 * and copy the existing header over. Set the "C" flag
1226 * ONLY after copying the rest of the data.
1228 if (len > (255 - ptr[1])) {
1229 return attr_shift(start, start + room, ptr, hdr_len, len, 8, 7);
1236 if ((fr_debug_flag > 3) && fr_log_fp) {
1237 fprintf(fr_log_fp, "\t\t%02x %02x %02x%02x%02x%02x (%u) %02x %02x %02x ",
1239 ptr[2], ptr[3], ptr[4], ptr[5],
1240 (ptr[3] << 16) | (ptr[4] << 8) | ptr[5],
1241 ptr[6], ptr[7], ptr[8]);
1242 print_hex_data(ptr + 9, len, 3);
1246 return (ptr + ptr[1]) - start;
1250 * Encode an RFC format TLV. This could be a standard attribute,
1251 * or a TLV data type. If it's a standard attribute, then
1252 * vp->attribute == attribute. Otherwise, attribute may be
1255 static ssize_t vp2attr_rfc(const RADIUS_PACKET *packet,
1256 const RADIUS_PACKET *original,
1257 const char *secret, const VALUE_PAIR **pvp,
1258 unsigned int attribute, uint8_t *ptr, size_t room)
1262 if (room < 2) return 0;
1264 ptr[0] = attribute & 0xff;
1267 if (room > ((unsigned) 255 - ptr[1])) room = 255 - ptr[1];
1269 len = vp2data_any(packet, original, secret, 0, pvp, ptr + ptr[1], room);
1270 if (len <= 0) return len;
1275 if ((fr_debug_flag > 3) && fr_log_fp) {
1276 fprintf(fr_log_fp, "\t\t%02x %02x ", ptr[0], ptr[1]);
1277 print_hex_data(ptr + 2, len, 3);
1286 * Encode a VSA which is a TLV. If it's in the RFC format, call
1287 * vp2attr_rfc. Otherwise, encode it here.
1289 static ssize_t vp2attr_vsa(const RADIUS_PACKET *packet,
1290 const RADIUS_PACKET *original,
1291 const char *secret, const VALUE_PAIR **pvp,
1292 unsigned int attribute, unsigned int vendor,
1293 uint8_t *ptr, size_t room)
1297 const VALUE_PAIR *vp = *pvp;
1300 * Unknown vendor: RFC format.
1301 * Known vendor and RFC format: go do that.
1303 dv = dict_vendorbyvalue(vendor);
1305 (!vp->flags.is_tlv && (dv->type == 1) && (dv->length == 1))) {
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)) {
1501 return vp2attr_rfc(packet, original, secret, pvp, vp->attribute,
1507 * Parse a data structure into a RADIUS attribute.
1509 int rad_vp2attr(const RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1510 const char *secret, const VALUE_PAIR **pvp, uint8_t *start,
1513 const VALUE_PAIR *vp;
1515 if (!pvp || !*pvp || !start || (room <= 2)) return -1;
1520 * RFC format attributes take the fast path.
1522 if (vp->vendor == 0) {
1523 if (vp->attribute > 255) return 0;
1526 * Message-Authenticator is hard-coded.
1528 if (vp->attribute == PW_MESSAGE_AUTHENTICATOR) {
1529 if (room < 18) return -1;
1532 start[0] = PW_MESSAGE_AUTHENTICATOR;
1534 memset(start + 2, 0, 16);
1536 if ((fr_debug_flag > 3) && fr_log_fp) {
1537 fprintf(fr_log_fp, "\t\t50 12 ...\n");
1541 *pvp = (*pvp)->next;
1545 return rad_vp2rfc(packet, original, secret, pvp,
1549 if (vp->vendor > FR_MAX_VENDOR) {
1550 return rad_vp2extended(packet, original, secret, pvp,
1554 if (vp->flags.wimax) {
1555 return rad_vp2wimax(packet, original, secret, pvp,
1559 return rad_vp2vsa(packet, original, secret, pvp,
1567 int rad_encode(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1570 radius_packet_t *hdr;
1572 uint16_t total_length;
1574 const VALUE_PAIR *reply;
1576 char ip_buffer[128];
1579 * A 4K packet, aligned on 64-bits.
1581 uint64_t data[MAX_PACKET_LEN / sizeof(uint64_t)];
1583 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1584 what = fr_packet_codes[packet->code];
1589 DEBUG("Sending %s of id %d to %s port %d\n",
1591 inet_ntop(packet->dst_ipaddr.af,
1592 &packet->dst_ipaddr.ipaddr,
1593 ip_buffer, sizeof(ip_buffer)),
1597 * Double-check some things based on packet code.
1599 switch (packet->code) {
1600 case PW_AUTHENTICATION_ACK:
1601 case PW_AUTHENTICATION_REJECT:
1602 case PW_ACCESS_CHALLENGE:
1604 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1610 * These packet vectors start off as all zero.
1612 case PW_ACCOUNTING_REQUEST:
1613 case PW_DISCONNECT_REQUEST:
1614 case PW_COA_REQUEST:
1615 memset(packet->vector, 0, sizeof(packet->vector));
1623 * Use memory on the stack, until we know how
1624 * large the packet will be.
1626 hdr = (radius_packet_t *) data;
1629 * Build standard header
1631 hdr->code = packet->code;
1632 hdr->id = packet->id;
1634 memcpy(hdr->vector, packet->vector, sizeof(hdr->vector));
1636 total_length = AUTH_HDR_LEN;
1639 * Load up the configuration values for the user
1645 * FIXME: Loop twice over the reply list. The first time,
1646 * calculate the total length of data. The second time,
1647 * allocate the memory, and fill in the VP's.
1649 * Hmm... this may be slower than just doing a small
1654 * Loop over the reply attributes for the packet.
1656 reply = packet->vps;
1659 const char *last_name = NULL;
1662 * Ignore non-wire attributes, but allow extended
1665 if ((reply->vendor == 0) &&
1666 ((reply->attribute & 0xFFFF) >= 256) &&
1667 !reply->flags.extended && !reply->flags.extended_flags) {
1670 * Permit the admin to send BADLY formatted
1671 * attributes with a debug build.
1673 if (reply->attribute == PW_RAW_ATTRIBUTE) {
1674 memcpy(ptr, reply->vp_octets, reply->length);
1675 len = reply->length;
1676 reply = reply->next;
1680 reply = reply->next;
1685 * Set the Message-Authenticator to the correct
1686 * length and initial value.
1688 if (reply->attribute == PW_MESSAGE_AUTHENTICATOR) {
1690 * Cache the offset to the
1691 * Message-Authenticator
1693 packet->offset = total_length;
1696 last_len = reply->length;
1698 last_name = reply->name;
1700 len = rad_vp2attr(packet, original, secret, &reply, ptr,
1701 ((uint8_t *) data) + sizeof(data) - ptr);
1702 if (len < 0) return -1;
1705 * Failed to encode the attribute, likely because
1706 * the packet is full.
1709 if (last_len != 0) {
1710 DEBUG("WARNING: Failed encoding attribute %s\n", last_name);
1712 DEBUG("WARNING: Skipping zero-length attribute %s\n", last_name);
1717 next: /* Used only for Raw-Attribute */
1720 total_length += len;
1721 } /* done looping over all attributes */
1724 * Fill in the rest of the fields, and copy the data over
1725 * from the local stack to the newly allocated memory.
1727 * Yes, all this 'memcpy' is slow, but it means
1728 * that we only allocate the minimum amount of
1729 * memory for a request.
1731 packet->data_len = total_length;
1732 packet->data = (uint8_t *) malloc(packet->data_len);
1733 if (!packet->data) {
1734 fr_strerror_printf("Out of memory");
1738 memcpy(packet->data, hdr, packet->data_len);
1739 hdr = (radius_packet_t *) packet->data;
1741 total_length = htons(total_length);
1742 memcpy(hdr->length, &total_length, sizeof(total_length));
1749 * Sign a previously encoded packet.
1751 int rad_sign(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1754 radius_packet_t *hdr = (radius_packet_t *)packet->data;
1757 * It wasn't assigned an Id, this is bad!
1759 if (packet->id < 0) {
1760 fr_strerror_printf("ERROR: RADIUS packets must be assigned an Id.");
1764 if (!packet->data || (packet->data_len < AUTH_HDR_LEN) ||
1765 (packet->offset < 0)) {
1766 fr_strerror_printf("ERROR: You must call rad_encode() before rad_sign()");
1771 * If there's a Message-Authenticator, update it
1772 * now, BEFORE updating the authentication vector.
1774 if (packet->offset > 0) {
1775 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
1777 switch (packet->code) {
1778 case PW_ACCOUNTING_REQUEST:
1779 case PW_ACCOUNTING_RESPONSE:
1780 case PW_DISCONNECT_REQUEST:
1781 case PW_DISCONNECT_ACK:
1782 case PW_DISCONNECT_NAK:
1783 case PW_COA_REQUEST:
1786 memset(hdr->vector, 0, AUTH_VECTOR_LEN);
1789 case PW_AUTHENTICATION_ACK:
1790 case PW_AUTHENTICATION_REJECT:
1791 case PW_ACCESS_CHALLENGE:
1793 fr_strerror_printf("ERROR: Cannot sign response packet without a request packet.");
1796 memcpy(hdr->vector, original->vector,
1800 default: /* others have vector already set to zero */
1806 * Set the authentication vector to zero,
1807 * calculate the signature, and put it
1808 * into the Message-Authenticator
1811 fr_hmac_md5(packet->data, packet->data_len,
1812 (const uint8_t *) secret, strlen(secret),
1814 memcpy(packet->data + packet->offset + 2,
1815 calc_auth_vector, AUTH_VECTOR_LEN);
1818 * Copy the original request vector back
1819 * to the raw packet.
1821 memcpy(hdr->vector, packet->vector, AUTH_VECTOR_LEN);
1825 * Switch over the packet code, deciding how to
1828 switch (packet->code) {
1830 * Request packets are not signed, bur
1831 * have a random authentication vector.
1833 case PW_AUTHENTICATION_REQUEST:
1834 case PW_STATUS_SERVER:
1838 * Reply packets are signed with the
1839 * authentication vector of the request.
1846 fr_MD5Init(&context);
1847 fr_MD5Update(&context, packet->data, packet->data_len);
1848 fr_MD5Update(&context, (const uint8_t *) secret,
1850 fr_MD5Final(digest, &context);
1852 memcpy(hdr->vector, digest, AUTH_VECTOR_LEN);
1853 memcpy(packet->vector, digest, AUTH_VECTOR_LEN);
1856 }/* switch over packet codes */
1862 * Reply to the request. Also attach
1863 * reply attribute value pairs and any user message provided.
1865 int rad_send(RADIUS_PACKET *packet, const RADIUS_PACKET *original,
1870 char ip_buffer[128];
1873 * Maybe it's a fake packet. Don't send it.
1875 if (!packet || (packet->sockfd < 0)) {
1879 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
1880 what = fr_packet_codes[packet->code];
1886 * First time through, allocate room for the packet
1888 if (!packet->data) {
1890 * Encode the packet.
1892 if (rad_encode(packet, original, secret) < 0) {
1897 * Re-sign it, including updating the
1898 * Message-Authenticator.
1900 if (rad_sign(packet, original, secret) < 0) {
1905 * If packet->data points to data, then we print out
1906 * the VP list again only for debugging.
1908 } else if (fr_debug_flag) {
1909 DEBUG("Sending %s of id %d to %s port %d\n", what, packet->id,
1910 inet_ntop(packet->dst_ipaddr.af,
1911 &packet->dst_ipaddr.ipaddr,
1912 ip_buffer, sizeof(ip_buffer)),
1915 for (reply = packet->vps; reply; reply = reply->next) {
1916 if ((reply->vendor == 0) &&
1917 ((reply->attribute & 0xFFFF) > 0xff)) continue;
1923 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
1927 * And send it on it's way.
1929 return rad_sendto(packet->sockfd, packet->data, packet->data_len, 0,
1930 &packet->src_ipaddr, packet->src_port,
1931 &packet->dst_ipaddr, packet->dst_port);
1935 * Do a comparison of two authentication digests by comparing
1936 * the FULL digest. Otehrwise, the server can be subject to
1937 * timing attacks that allow attackers find a valid message
1940 * http://www.cs.rice.edu/~dwallach/pub/crosby-timing2009.pdf
1942 int rad_digest_cmp(const uint8_t *a, const uint8_t *b, size_t length)
1947 for (i = 0; i < length; i++) {
1948 result |= a[i] ^ b[i];
1951 return result; /* 0 is OK, !0 is !OK, just like memcmp */
1956 * Validates the requesting client NAS. Calculates the
1957 * signature based on the clients private key.
1959 static int calc_acctdigest(RADIUS_PACKET *packet, const char *secret)
1961 uint8_t digest[AUTH_VECTOR_LEN];
1965 * Zero out the auth_vector in the received packet.
1966 * Then append the shared secret to the received packet,
1967 * and calculate the MD5 sum. This must be the same
1968 * as the original MD5 sum (packet->vector).
1970 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
1973 * MD5(packet + secret);
1975 fr_MD5Init(&context);
1976 fr_MD5Update(&context, packet->data, packet->data_len);
1977 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
1978 fr_MD5Final(digest, &context);
1981 * Return 0 if OK, 2 if not OK.
1983 if (rad_digest_cmp(digest, packet->vector, AUTH_VECTOR_LEN) != 0) return 2;
1989 * Validates the requesting client NAS. Calculates the
1990 * signature based on the clients private key.
1992 static int calc_replydigest(RADIUS_PACKET *packet, RADIUS_PACKET *original,
1995 uint8_t calc_digest[AUTH_VECTOR_LEN];
2001 if (original == NULL) {
2006 * Copy the original vector in place.
2008 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2011 * MD5(packet + secret);
2013 fr_MD5Init(&context);
2014 fr_MD5Update(&context, packet->data, packet->data_len);
2015 fr_MD5Update(&context, (const uint8_t *) secret, strlen(secret));
2016 fr_MD5Final(calc_digest, &context);
2019 * Copy the packet's vector back to the packet.
2021 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2024 * Return 0 if OK, 2 if not OK.
2026 if (rad_digest_cmp(packet->vector, calc_digest, AUTH_VECTOR_LEN) != 0) return 2;
2032 * Check if a set of RADIUS formatted TLVs are OK.
2034 int rad_tlv_ok(const uint8_t *data, size_t length,
2035 size_t dv_type, size_t dv_length)
2037 const uint8_t *end = data + length;
2039 if ((dv_length > 2) || (dv_type == 0) || (dv_type > 4)) {
2040 fr_strerror_printf("rad_tlv_ok: Invalid arguments");
2044 while (data < end) {
2047 if ((data + dv_type + dv_length) > end) {
2048 fr_strerror_printf("Attribute header overflow");
2054 if ((data[0] == 0) && (data[1] == 0) &&
2055 (data[2] == 0) && (data[3] == 0)) {
2057 fr_strerror_printf("Invalid attribute 0");
2062 fr_strerror_printf("Invalid attribute > 2^24");
2068 if ((data[1] == 0) && (data[1] == 0)) goto zero;
2072 if (data[0] == 0) goto zero;
2076 fr_strerror_printf("Internal sanity check failed");
2080 switch (dv_length) {
2085 if (data[dv_type + 1] != 0) {
2086 fr_strerror_printf("Attribute is longer than 256 octets");
2091 attrlen = data[dv_type + dv_length - 1];
2096 fr_strerror_printf("Internal sanity check failed");
2100 if (attrlen < (dv_type + dv_length)) {
2101 fr_strerror_printf("Attribute header has invalid length");
2105 if (attrlen > length) {
2106 fr_strerror_printf("Attribute overflows container");
2119 * See if the data pointed to by PTR is a valid RADIUS packet.
2121 * packet is not 'const * const' because we may update data_len,
2122 * if there's more data in the UDP packet than in the RADIUS packet.
2124 int rad_packet_ok(RADIUS_PACKET *packet, int flags)
2129 radius_packet_t *hdr;
2130 char host_ipaddr[128];
2136 * Check for packets smaller than the packet header.
2138 * RFC 2865, Section 3., subsection 'length' says:
2140 * "The minimum length is 20 ..."
2142 if (packet->data_len < AUTH_HDR_LEN) {
2143 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (received %d < minimum %d)",
2144 inet_ntop(packet->src_ipaddr.af,
2145 &packet->src_ipaddr.ipaddr,
2146 host_ipaddr, sizeof(host_ipaddr)),
2147 (int) packet->data_len, AUTH_HDR_LEN);
2152 * RFC 2865, Section 3., subsection 'length' says:
2154 * " ... and maximum length is 4096."
2156 if (packet->data_len > MAX_PACKET_LEN) {
2157 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (received %d > maximum %d)",
2158 inet_ntop(packet->src_ipaddr.af,
2159 &packet->src_ipaddr.ipaddr,
2160 host_ipaddr, sizeof(host_ipaddr)),
2161 (int) packet->data_len, MAX_PACKET_LEN);
2166 * Check for packets with mismatched size.
2167 * i.e. We've received 128 bytes, and the packet header
2168 * says it's 256 bytes long.
2170 totallen = (packet->data[2] << 8) | packet->data[3];
2171 hdr = (radius_packet_t *)packet->data;
2174 * Code of 0 is not understood.
2175 * Code of 16 or greate is not understood.
2177 if ((hdr->code == 0) ||
2178 (hdr->code >= FR_MAX_PACKET_CODE)) {
2179 fr_strerror_printf("WARNING: Bad RADIUS packet from host %s: unknown packet code%d ",
2180 inet_ntop(packet->src_ipaddr.af,
2181 &packet->src_ipaddr.ipaddr,
2182 host_ipaddr, sizeof(host_ipaddr)),
2188 * Message-Authenticator is required in Status-Server
2189 * packets, otherwise they can be trivially forged.
2191 if (hdr->code == PW_STATUS_SERVER) require_ma = 1;
2194 * It's also required if the caller asks for it.
2196 if (flags) require_ma = 1;
2199 * Repeat the length checks. This time, instead of
2200 * looking at the data we received, look at the value
2201 * of the 'length' field inside of the packet.
2203 * Check for packets smaller than the packet header.
2205 * RFC 2865, Section 3., subsection 'length' says:
2207 * "The minimum length is 20 ..."
2209 if (totallen < AUTH_HDR_LEN) {
2210 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too short (length %d < minimum %d)",
2211 inet_ntop(packet->src_ipaddr.af,
2212 &packet->src_ipaddr.ipaddr,
2213 host_ipaddr, sizeof(host_ipaddr)),
2214 totallen, AUTH_HDR_LEN);
2219 * And again, for the value of the 'length' field.
2221 * RFC 2865, Section 3., subsection 'length' says:
2223 * " ... and maximum length is 4096."
2225 if (totallen > MAX_PACKET_LEN) {
2226 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: too long (length %d > maximum %d)",
2227 inet_ntop(packet->src_ipaddr.af,
2228 &packet->src_ipaddr.ipaddr,
2229 host_ipaddr, sizeof(host_ipaddr)),
2230 totallen, MAX_PACKET_LEN);
2235 * RFC 2865, Section 3., subsection 'length' says:
2237 * "If the packet is shorter than the Length field
2238 * indicates, it MUST be silently discarded."
2240 * i.e. No response to the NAS.
2242 if (packet->data_len < totallen) {
2243 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: received %d octets, packet length says %d",
2244 inet_ntop(packet->src_ipaddr.af,
2245 &packet->src_ipaddr.ipaddr,
2246 host_ipaddr, sizeof(host_ipaddr)),
2247 (int) packet->data_len, totallen);
2252 * RFC 2865, Section 3., subsection 'length' says:
2254 * "Octets outside the range of the Length field MUST be
2255 * treated as padding and ignored on reception."
2257 if (packet->data_len > totallen) {
2259 * We're shortening the packet below, but just
2260 * to be paranoid, zero out the extra data.
2262 memset(packet->data + totallen, 0, packet->data_len - totallen);
2263 packet->data_len = totallen;
2267 * Walk through the packet's attributes, ensuring that
2268 * they add up EXACTLY to the size of the packet.
2270 * If they don't, then the attributes either under-fill
2271 * or over-fill the packet. Any parsing of the packet
2272 * is impossible, and will result in unknown side effects.
2274 * This would ONLY happen with buggy RADIUS implementations,
2275 * or with an intentional attack. Either way, we do NOT want
2276 * to be vulnerable to this problem.
2279 count = totallen - AUTH_HDR_LEN;
2284 * We need at least 2 bytes to check the
2288 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute header overflows the packet",
2289 inet_ntop(packet->src_ipaddr.af,
2290 &packet->src_ipaddr.ipaddr,
2291 host_ipaddr, sizeof(host_ipaddr)));
2296 * Attribute number zero is NOT defined.
2299 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Invalid attribute 0",
2300 inet_ntop(packet->src_ipaddr.af,
2301 &packet->src_ipaddr.ipaddr,
2302 host_ipaddr, sizeof(host_ipaddr)));
2307 * Attributes are at LEAST as long as the ID & length
2308 * fields. Anything shorter is an invalid attribute.
2311 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u too short",
2312 inet_ntop(packet->src_ipaddr.af,
2313 &packet->src_ipaddr.ipaddr,
2314 host_ipaddr, sizeof(host_ipaddr)),
2320 * If there are fewer bytes in the packet than in the
2321 * attribute, it's a bad packet.
2323 if (count < attr[1]) {
2324 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: attribute %u data overflows the packet",
2325 inet_ntop(packet->src_ipaddr.af,
2326 &packet->src_ipaddr.ipaddr,
2327 host_ipaddr, sizeof(host_ipaddr)),
2333 * Sanity check the attributes for length.
2336 default: /* don't do anything by default */
2340 * If there's an EAP-Message, we require
2341 * a Message-Authenticator.
2343 case PW_EAP_MESSAGE:
2347 case PW_MESSAGE_AUTHENTICATOR:
2348 if (attr[1] != 2 + AUTH_VECTOR_LEN) {
2349 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: Message-Authenticator has invalid length %d",
2350 inet_ntop(packet->src_ipaddr.af,
2351 &packet->src_ipaddr.ipaddr,
2352 host_ipaddr, sizeof(host_ipaddr)),
2361 * FIXME: Look up the base 255 attributes in the
2362 * dictionary, and switch over their type. For
2363 * integer/date/ip, the attribute length SHOULD
2366 count -= attr[1]; /* grab the attribute length */
2368 num_attributes++; /* seen one more attribute */
2372 * If the attributes add up to a packet, it's allowed.
2374 * If not, we complain, and throw the packet away.
2377 fr_strerror_printf("WARNING: Malformed RADIUS packet from host %s: packet attributes do NOT exactly fill the packet",
2378 inet_ntop(packet->src_ipaddr.af,
2379 &packet->src_ipaddr.ipaddr,
2380 host_ipaddr, sizeof(host_ipaddr)));
2385 * If we're configured to look for a maximum number of
2386 * attributes, and we've seen more than that maximum,
2387 * then throw the packet away, as a possible DoS.
2389 if ((fr_max_attributes > 0) &&
2390 (num_attributes > fr_max_attributes)) {
2391 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
2392 inet_ntop(packet->src_ipaddr.af,
2393 &packet->src_ipaddr.ipaddr,
2394 host_ipaddr, sizeof(host_ipaddr)),
2395 num_attributes, fr_max_attributes);
2400 * http://www.freeradius.org/rfc/rfc2869.html#EAP-Message
2402 * A packet with an EAP-Message attribute MUST also have
2403 * a Message-Authenticator attribute.
2405 * A Message-Authenticator all by itself is OK, though.
2407 * Similarly, Status-Server packets MUST contain
2408 * Message-Authenticator attributes.
2410 if (require_ma && ! seen_ma) {
2411 fr_strerror_printf("WARNING: Insecure packet from host %s: Packet does not contain required Message-Authenticator attribute",
2412 inet_ntop(packet->src_ipaddr.af,
2413 &packet->src_ipaddr.ipaddr,
2414 host_ipaddr, sizeof(host_ipaddr)));
2419 * Fill RADIUS header fields
2421 packet->code = hdr->code;
2422 packet->id = hdr->id;
2423 memcpy(packet->vector, hdr->vector, AUTH_VECTOR_LEN);
2430 * Receive UDP client requests, and fill in
2431 * the basics of a RADIUS_PACKET structure.
2433 RADIUS_PACKET *rad_recv(int fd, int flags)
2436 RADIUS_PACKET *packet;
2439 * Allocate the new request data structure
2441 if ((packet = malloc(sizeof(*packet))) == NULL) {
2442 fr_strerror_printf("out of memory");
2445 memset(packet, 0, sizeof(*packet));
2448 sock_flags = MSG_PEEK;
2452 packet->data_len = rad_recvfrom(fd, &packet->data, sock_flags,
2453 &packet->src_ipaddr, &packet->src_port,
2454 &packet->dst_ipaddr, &packet->dst_port);
2457 * Check for socket errors.
2459 if (packet->data_len < 0) {
2460 fr_strerror_printf("Error receiving packet: %s", strerror(errno));
2461 /* packet->data is NULL */
2467 * If the packet is too big, then rad_recvfrom did NOT
2468 * allocate memory. Instead, it just discarded the
2471 if (packet->data_len > MAX_PACKET_LEN) {
2472 fr_strerror_printf("Discarding packet: Larger than RFC limitation of 4096 bytes.");
2473 /* packet->data is NULL */
2479 * Read no data. Continue.
2480 * This check is AFTER the MAX_PACKET_LEN check above, because
2481 * if the packet is larger than MAX_PACKET_LEN, we also have
2482 * packet->data == NULL
2484 if ((packet->data_len == 0) || !packet->data) {
2485 fr_strerror_printf("Empty packet: Socket is not ready.");
2491 * See if it's a well-formed RADIUS packet.
2493 if (!rad_packet_ok(packet, flags)) {
2499 * Remember which socket we read the packet from.
2501 packet->sockfd = fd;
2504 * FIXME: Do even more filtering by only permitting
2505 * certain IP's. The problem is that we don't know
2506 * how to do this properly for all possible clients...
2510 * Explicitely set the VP list to empty.
2514 if (fr_debug_flag) {
2515 char host_ipaddr[128];
2517 if ((packet->code > 0) && (packet->code < FR_MAX_PACKET_CODE)) {
2518 DEBUG("rad_recv: %s packet from host %s port %d",
2519 fr_packet_codes[packet->code],
2520 inet_ntop(packet->src_ipaddr.af,
2521 &packet->src_ipaddr.ipaddr,
2522 host_ipaddr, sizeof(host_ipaddr)),
2525 DEBUG("rad_recv: Packet from host %s port %d code=%d",
2526 inet_ntop(packet->src_ipaddr.af,
2527 &packet->src_ipaddr.ipaddr,
2528 host_ipaddr, sizeof(host_ipaddr)),
2532 DEBUG(", id=%d, length=%d\n",
2533 packet->id, (int) packet->data_len);
2537 if ((fr_debug_flag > 3) && fr_log_fp) rad_print_hex(packet);
2545 * Verify the signature of a packet.
2547 int rad_verify(RADIUS_PACKET *packet, RADIUS_PACKET *original,
2554 if (!packet || !packet->data) return -1;
2557 * Before we allocate memory for the attributes, do more
2560 ptr = packet->data + AUTH_HDR_LEN;
2561 length = packet->data_len - AUTH_HDR_LEN;
2562 while (length > 0) {
2563 uint8_t msg_auth_vector[AUTH_VECTOR_LEN];
2564 uint8_t calc_auth_vector[AUTH_VECTOR_LEN];
2569 default: /* don't do anything. */
2573 * Note that more than one Message-Authenticator
2574 * attribute is invalid.
2576 case PW_MESSAGE_AUTHENTICATOR:
2577 memcpy(msg_auth_vector, &ptr[2], sizeof(msg_auth_vector));
2578 memset(&ptr[2], 0, AUTH_VECTOR_LEN);
2580 switch (packet->code) {
2584 case PW_ACCOUNTING_REQUEST:
2585 case PW_ACCOUNTING_RESPONSE:
2586 case PW_DISCONNECT_REQUEST:
2587 case PW_DISCONNECT_ACK:
2588 case PW_DISCONNECT_NAK:
2589 case PW_COA_REQUEST:
2592 memset(packet->data + 4, 0, AUTH_VECTOR_LEN);
2595 case PW_AUTHENTICATION_ACK:
2596 case PW_AUTHENTICATION_REJECT:
2597 case PW_ACCESS_CHALLENGE:
2599 fr_strerror_printf("ERROR: Cannot validate Message-Authenticator in response packet without a request packet.");
2602 memcpy(packet->data + 4, original->vector, AUTH_VECTOR_LEN);
2606 fr_hmac_md5(packet->data, packet->data_len,
2607 (const uint8_t *) secret, strlen(secret),
2609 if (rad_digest_cmp(calc_auth_vector, msg_auth_vector,
2610 sizeof(calc_auth_vector)) != 0) {
2612 fr_strerror_printf("Received packet from %s with invalid Message-Authenticator! (Shared secret is incorrect.)",
2613 inet_ntop(packet->src_ipaddr.af,
2614 &packet->src_ipaddr.ipaddr,
2615 buffer, sizeof(buffer)));
2616 /* Silently drop packet, according to RFC 3579 */
2618 } /* else the message authenticator was good */
2621 * Reinitialize Authenticators.
2623 memcpy(&ptr[2], msg_auth_vector, AUTH_VECTOR_LEN);
2624 memcpy(packet->data + 4, packet->vector, AUTH_VECTOR_LEN);
2626 } /* switch over the attributes */
2630 } /* loop over the packet, sanity checking the attributes */
2633 * It looks like a RADIUS packet, but we can't validate
2636 if ((packet->code == 0) || (packet->code >= FR_MAX_PACKET_CODE)) {
2638 fr_strerror_printf("Received Unknown packet code %d "
2639 "from client %s port %d: Cannot validate signature.",
2641 inet_ntop(packet->src_ipaddr.af,
2642 &packet->src_ipaddr.ipaddr,
2643 buffer, sizeof(buffer)),
2649 * Calculate and/or verify digest.
2651 switch(packet->code) {
2655 case PW_AUTHENTICATION_REQUEST:
2656 case PW_STATUS_SERVER:
2658 * The authentication vector is random
2659 * nonsense, invented by the client.
2663 case PW_COA_REQUEST:
2664 case PW_DISCONNECT_REQUEST:
2665 case PW_ACCOUNTING_REQUEST:
2666 if (calc_acctdigest(packet, secret) > 1) {
2667 fr_strerror_printf("Received %s packet "
2668 "from client %s with invalid signature! (Shared secret is incorrect.)",
2669 fr_packet_codes[packet->code],
2670 inet_ntop(packet->src_ipaddr.af,
2671 &packet->src_ipaddr.ipaddr,
2672 buffer, sizeof(buffer)));
2677 /* Verify the reply digest */
2678 case PW_AUTHENTICATION_ACK:
2679 case PW_AUTHENTICATION_REJECT:
2680 case PW_ACCESS_CHALLENGE:
2681 case PW_ACCOUNTING_RESPONSE:
2682 case PW_DISCONNECT_ACK:
2683 case PW_DISCONNECT_NAK:
2686 rcode = calc_replydigest(packet, original, secret);
2688 fr_strerror_printf("Received %s packet "
2689 "from home server %s port %d with invalid signature! (Shared secret is incorrect.)",
2690 fr_packet_codes[packet->code],
2691 inet_ntop(packet->src_ipaddr.af,
2692 &packet->src_ipaddr.ipaddr,
2693 buffer, sizeof(buffer)),
2700 fr_strerror_printf("Received Unknown packet code %d "
2701 "from client %s port %d: Cannot validate signature",
2703 inet_ntop(packet->src_ipaddr.af,
2704 &packet->src_ipaddr.ipaddr,
2705 buffer, sizeof(buffer)),
2715 * Create a "raw" attribute from the attribute contents.
2717 static ssize_t data2vp_raw(UNUSED const RADIUS_PACKET *packet,
2718 UNUSED const RADIUS_PACKET *original,
2719 UNUSED const char *secret,
2720 unsigned int attribute, unsigned int vendor,
2721 const uint8_t *data, size_t length,
2727 * Keep the next function happy.
2729 vp = pairalloc(NULL);
2730 vp = paircreate_raw(attribute, vendor, PW_TYPE_OCTETS, vp);
2732 fr_strerror_printf("data2vp_raw: Failed creating attribute");
2736 vp->length = length;
2739 * If the data is too large, mark it as a "TLV".
2741 if (length <= sizeof(vp->vp_octets)) {
2742 memcpy(vp->vp_octets, data, length);
2744 vp->type = PW_TYPE_TLV;
2745 vp->vp_tlv = malloc(length);
2750 memcpy(vp->vp_tlv, data, length);
2759 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
2760 const RADIUS_PACKET *original,
2762 unsigned int attribute, unsigned int vendor,
2764 const uint8_t *start, size_t length,
2768 * Create any kind of VP from the attribute contents.
2770 * Will return -1 on error, or "length".
2772 static ssize_t data2vp_any(const RADIUS_PACKET *packet,
2773 const RADIUS_PACKET *original,
2774 const char *secret, int nest,
2775 unsigned int attribute, unsigned int vendor,
2776 const uint8_t *data, size_t length,
2779 int data_offset = 0;
2781 VALUE_PAIR *vp = NULL;
2785 * Hacks for CUI. The WiMAX spec says that it
2786 * can be zero length, even though this is
2787 * forbidden by the RADIUS specs. So... we make
2788 * a special case for it.
2790 if ((vendor == 0) &&
2791 (attribute == PW_CHARGEABLE_USER_IDENTITY)) {
2792 data = (const uint8_t *) "";
2800 da = dict_attrbyvalue(attribute, vendor);
2803 * Unknown attribute. Create it as a "raw" attribute.
2806 VP_TRACE("Not found %u.%u\n", vendor, attribute);
2808 if (vp) pairfree(&vp);
2809 return data2vp_raw(packet, original, secret,
2810 attribute, vendor, data, length, pvp);
2814 * TLVs are handled first. They can't be tagged, and
2815 * they can't be encrypted.
2817 if (da->type == PW_TYPE_TLV) {
2818 VP_TRACE("Found TLV %u.%u\n", vendor, attribute);
2819 return data2vp_tlvs(packet, original, secret,
2820 attribute, vendor, nest,
2825 * The attribute is known, and well formed. We can now
2826 * create it. The main failure from here on in is being
2835 if (vp->flags.has_tag) {
2836 if (TAG_VALID(data[0]) ||
2837 (vp->flags.encrypt == FLAG_ENCRYPT_TUNNEL_PASSWORD)) {
2839 * Tunnel passwords REQUIRE a tag, even
2840 * if don't have a valid tag.
2842 vp->flags.tag = data[0];
2844 if ((vp->type == PW_TYPE_STRING) ||
2845 (vp->type == PW_TYPE_OCTETS)) {
2846 if (length == 0) goto raw;
2853 * Copy the data to be decrypted
2855 vp->length = length - data_offset;
2856 memcpy(&vp->vp_octets[0], data + data_offset, vp->length);
2859 * Decrypt the attribute.
2861 switch (vp->flags.encrypt) {
2865 case FLAG_ENCRYPT_USER_PASSWORD:
2867 rad_pwdecode(vp->vp_strvalue,
2871 rad_pwdecode(vp->vp_strvalue,
2875 if (vp->attribute == PW_USER_PASSWORD) {
2876 vp->length = strlen(vp->vp_strvalue);
2881 * Tunnel-Password's may go ONLY
2882 * in response packets.
2884 case FLAG_ENCRYPT_TUNNEL_PASSWORD:
2885 if (!original) goto raw;
2887 if (rad_tunnel_pwdecode(vp->vp_octets, &vp->length,
2888 secret, original->vector) < 0) {
2894 * Ascend-Send-Secret
2895 * Ascend-Receive-Secret
2897 case FLAG_ENCRYPT_ASCEND_SECRET:
2901 uint8_t my_digest[AUTH_VECTOR_LEN];
2902 make_secret(my_digest,
2905 memcpy(vp->vp_strvalue, my_digest,
2907 vp->vp_strvalue[AUTH_VECTOR_LEN] = '\0';
2908 vp->length = strlen(vp->vp_strvalue);
2914 } /* switch over encryption flags */
2918 case PW_TYPE_STRING:
2919 case PW_TYPE_OCTETS:
2920 case PW_TYPE_ABINARY:
2921 /* nothing more to do */
2925 if (vp->length != 1) goto raw;
2927 vp->vp_integer = vp->vp_octets[0];
2932 if (vp->length != 2) goto raw;
2934 vp->vp_integer = (vp->vp_octets[0] << 8) | vp->vp_octets[1];
2937 case PW_TYPE_INTEGER:
2938 if (vp->length != 4) goto raw;
2940 memcpy(&vp->vp_integer, vp->vp_octets, 4);
2941 vp->vp_integer = ntohl(vp->vp_integer);
2943 if (vp->flags.has_tag) vp->vp_integer &= 0x00ffffff;
2946 * Try to get named VALUEs
2950 dval = dict_valbyattr(vp->attribute, vp->vendor,
2953 strlcpy(vp->vp_strvalue,
2955 sizeof(vp->vp_strvalue));
2961 if (vp->length != 4) goto raw;
2963 memcpy(&vp->vp_date, vp->vp_octets, 4);
2964 vp->vp_date = ntohl(vp->vp_date);
2968 case PW_TYPE_IPADDR:
2969 if (vp->length != 4) goto raw;
2971 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
2975 * IPv6 interface ID is 8 octets long.
2978 if (vp->length != 8) goto raw;
2979 /* vp->vp_ifid == vp->vp_octets */
2983 * IPv6 addresses are 16 octets long
2985 case PW_TYPE_IPV6ADDR:
2986 if (vp->length != 16) goto raw;
2987 /* vp->vp_ipv6addr == vp->vp_octets */
2991 * IPv6 prefixes are 2 to 18 octets long.
2993 * RFC 3162: The first octet is unused.
2994 * The second is the length of the prefix
2995 * the rest are the prefix data.
2997 * The prefix length can have value 0 to 128.
2999 case PW_TYPE_IPV6PREFIX:
3000 if (vp->length < 2 || vp->length > 18) goto raw;
3001 if (vp->vp_octets[1] > 128) goto raw;
3004 * FIXME: double-check that
3005 * (vp->vp_octets[1] >> 3) matches vp->length + 2
3007 if (vp->length < 18) {
3008 memset(vp->vp_octets + vp->length, 0,
3013 case PW_TYPE_SIGNED:
3014 if (vp->length != 4) goto raw;
3017 * Overload vp_integer for ntohl, which takes
3018 * uint32_t, not int32_t
3020 memcpy(&vp->vp_integer, vp->vp_octets, 4);
3021 vp->vp_integer = ntohl(vp->vp_integer);
3022 memcpy(&vp->vp_signed, &vp->vp_integer, 4);
3027 fr_strerror_printf("data2vp_any: Internal sanity check failed");
3030 case PW_TYPE_COMBO_IP:
3031 if (vp->length == 4) {
3032 vp->type = PW_TYPE_IPADDR;
3033 memcpy(&vp->vp_ipaddr, vp->vp_octets, 4);
3036 } else if (vp->length == 16) {
3037 vp->type = PW_TYPE_IPV6ADDR;
3038 /* vp->vp_ipv6addr == vp->vp_octets */
3055 * Convert a top-level VSA to a VP.
3057 static ssize_t attr2vp_vsa(const RADIUS_PACKET *packet,
3058 const RADIUS_PACKET *original,
3059 const char *secret, unsigned int vendor,
3060 size_t dv_type, size_t dv_length,
3061 const uint8_t *data, size_t length,
3064 unsigned int attribute;
3065 ssize_t attrlen, my_len;
3068 if (length <= (dv_type + dv_length)) {
3069 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3076 /* data[0] must be zero */
3077 attribute = data[1] << 16;
3078 attribute |= data[2] << 8;
3079 attribute |= data[3];
3083 attribute = data[0] << 8;
3084 attribute |= data[1];
3088 attribute = data[0];
3092 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3096 switch (dv_length) {
3098 /* data[dv_type] must be zero */
3099 attrlen = data[dv_type + 1];
3103 attrlen = data[dv_type];
3111 fr_strerror_printf("attr2vp_vsa: Internal sanity check failed");
3116 if (attrlen <= (ssize_t) (dv_type + dv_length)) {
3117 fr_strerror_printf("attr2vp_vsa: Failure to call rad_tlv_ok");
3122 attrlen -= (dv_type + dv_length);
3124 my_len = data2vp_any(packet, original, secret, 0,
3126 data + dv_type + dv_length, attrlen, pvp);
3127 if (my_len < 0) return my_len;
3130 if (my_len != attrlen) {
3132 fr_strerror_printf("attr2vp_vsa: Incomplete decode %d != %d",
3133 (int) my_len, (int) attrlen);
3138 return dv_type + dv_length + attrlen;
3142 * Convert one or more TLVs to VALUE_PAIRs. This function can
3143 * be called recursively...
3145 static ssize_t data2vp_tlvs(const RADIUS_PACKET *packet,
3146 const RADIUS_PACKET *original,
3148 unsigned int attribute, unsigned int vendor,
3150 const uint8_t *start, size_t length,
3153 size_t dv_type, dv_length;
3154 const uint8_t *data, *end;
3155 VALUE_PAIR *head, **last, *vp;
3160 * The default format for a VSA is the RFC recommended
3167 * Top-level TLVs can be of a weird format. TLVs
3168 * encapsulated in a TLV can only be in the RFC format.
3172 dv = dict_vendorbyvalue(vendor);
3175 dv_length = dv->length;
3176 /* dict.c enforces sane values on the above fields */
3180 if (nest >= fr_attr_max_tlv) {
3181 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in recursion");
3186 * The VSAs do not exactly fill the data,
3187 * The *entire* TLV is malformed.
3189 if (rad_tlv_ok(data, length, dv_type, dv_length) < 0) {
3190 VP_TRACE("TLV malformed %u.%u\n", vendor, attribute);
3191 return data2vp_raw(packet, original, secret,
3192 attribute, vendor, data, length, pvp);
3195 end = data + length;
3199 while (data < end) {
3200 unsigned int my_attr;
3201 unsigned int my_len;
3204 if ((data + dv_type + dv_length) > end) {
3205 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: Insufficient data");
3213 my_attr = attribute;
3214 my_attr |= ((data[0] & fr_attr_mask[nest + 1])
3215 << fr_attr_shift[nest + 1]);
3218 my_attr = (data[0] << 8) | data[1];
3222 my_attr = (data[1] << 16) | (data[1] << 8) | data[3];
3226 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3230 switch (dv_length) {
3237 my_len = data[dv_type + dv_length - 1];
3241 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed");
3246 if (my_len < (dv_type + dv_length)) {
3247 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: underflow");
3252 if ((data + my_len) > end) {
3253 fr_strerror_printf("data2vp_tlvs: Internal sanity check failed in tlvs: overflow");
3259 my_len -= dv_type + dv_length;
3262 * If this returns > 0, it returns "my_len"
3264 if (data2vp_any(packet, original, secret, nest + 1,
3266 data + dv_type + dv_length, my_len, &vp) < 0) {
3271 data += my_len + dv_type + dv_length;
3281 return data - start;
3286 * Group "continued" attributes together, and create VPs from them.
3287 * The caller ensures that the RADIUS packet is OK, and that the
3288 * continuations have all been checked.
3290 static ssize_t data2vp_continued(const RADIUS_PACKET *packet,
3291 const RADIUS_PACKET *original,
3293 const uint8_t *start, size_t length,
3294 VALUE_PAIR **pvp, int nest,
3295 unsigned int attribute, unsigned int vendor,
3296 int first_offset, int later_offset,
3300 uint8_t *attr, *ptr;
3301 const uint8_t *data;
3303 attr = malloc(attrlen);
3305 fr_strerror_printf("Out of memory");
3316 memcpy(ptr, data + first_offset, data[1] - first_offset);
3317 ptr += data[1] - first_offset;
3318 left -= data[1] - first_offset;
3323 if (data >= (start + length)) {
3324 fr_strerror_printf("data2vp_continued: Internal sanity check failed");
3328 memcpy(ptr, data + later_offset, data[1] - later_offset);
3329 ptr += data[1] - later_offset;
3330 left -= data[1] - later_offset;
3334 left = data2vp_any(packet, original, secret, nest,
3336 attr, attrlen, pvp);
3338 if (left < 0) return left;
3340 return data - start;
3345 * Create a "raw" VALUE_PAIR from a RADIUS attribute.
3347 ssize_t rad_attr2vp_raw(const RADIUS_PACKET *packet,
3348 const RADIUS_PACKET *original,
3350 const uint8_t *data, size_t length,
3355 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3356 fr_strerror_printf("rad_attr2vp_raw: Invalid length");
3360 my_len = data2vp_raw(packet, original, secret, data[0], 0,
3361 data + 2, data[1] - 2, pvp);
3362 if (my_len < 0) return my_len;
3369 * Get the length of the data portion of all of the contiguous
3370 * continued attributes.
3372 * 0 for "no continuation"
3373 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3375 static ssize_t wimax_attrlen(uint32_t vendor,
3376 const uint8_t *start, const uint8_t *end)
3379 const uint8_t *data = start;
3381 if ((data[8] & 0x80) == 0) return 0;
3382 total = data[7] - 3;
3385 while (data < end) {
3387 if ((data + 9) > end) return -1;
3389 if ((data[0] != PW_VENDOR_SPECIFIC) ||
3391 (memcmp(data + 2, &vendor, 4) != 0) ||
3392 (data[6] != start[6]) ||
3393 ((data[7] + 6) != data[1])) return -1;
3395 total += data[7] - 3;
3396 if ((data[8] & 0x80) == 0) break;
3405 * Get the length of the data portion of all of the contiguous
3406 * continued attributes.
3408 * 0 for "no continuation"
3409 * -1 on malformed packets (continuation followed by non-wimax, etc.)
3411 static ssize_t extended_attrlen(const uint8_t *start, const uint8_t *end)
3414 const uint8_t *data = start;
3416 if ((data[3] & 0x80) == 0) return 0;
3417 total = data[1] - 4;
3420 while (data < end) {
3421 if ((data + 4) > end) return -1;
3423 if ((data[0] != start[0]) ||
3425 (data[2] != start[2])) return -1;
3427 total += data[1] - 4;
3428 if ((data[3] & 0x80) == 0) break;
3437 * Create WiMAX VALUE_PAIRs from a RADIUS attribute.
3439 ssize_t rad_attr2vp_wimax(const RADIUS_PACKET *packet,
3440 const RADIUS_PACKET *original,
3442 const uint8_t *data, size_t length,
3446 unsigned int attribute;
3449 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3450 fr_strerror_printf("rad_attr2vp_wimax: Invalid length");
3454 if (data[0] != PW_VENDOR_SPECIFIC) {
3455 fr_strerror_printf("rad_attr2vp_wimax: Invalid attribute");
3460 * Not enough room for a Vendor-Id. + WiMAX header
3463 return rad_attr2vp_raw(packet, original, secret,
3467 memcpy(&lvalue, data + 2, 4);
3468 lvalue = ntohl(lvalue);
3473 if (lvalue != VENDORPEC_WIMAX) {
3476 dv = dict_vendorbyvalue(lvalue);
3477 if (!dv || !dv->flags) {
3478 fr_strerror_printf("rad_attr2vp_wimax: Not a WiMAX attribute");
3484 * The WiMAX attribute is encapsulated in a VSA. If the
3485 * WiMAX length disagrees with the VSA length, it's malformed.
3487 if ((data[7] + 6) != data[1]) {
3488 return rad_attr2vp_raw(packet, original, secret,
3492 attribute = data[6];
3495 * Attribute is continued. Do some more work.
3498 my_len = wimax_attrlen(htonl(lvalue), data, data + length);
3500 return rad_attr2vp_raw(packet, original, secret,
3504 return data2vp_continued(packet, original, secret,
3505 data, length, pvp, 0,
3510 my_len = data2vp_any(packet, original, secret, 0, attribute, lvalue,
3511 data + 9, data[1] - 9, pvp);
3512 if (my_len < 0) return my_len;
3518 * Create Vendor-Specifc VALUE_PAIRs from a RADIUS attribute.
3520 ssize_t rad_attr2vp_vsa(const RADIUS_PACKET *packet,
3521 const RADIUS_PACKET *original,
3523 const uint8_t *data, size_t length,
3526 size_t dv_type, dv_length;
3531 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3532 fr_strerror_printf("rad_attr2vp_vsa: Invalid length");
3536 if (data[0] != PW_VENDOR_SPECIFIC) {
3537 fr_strerror_printf("rad_attr2vp_vsa: Invalid attribute");
3542 * Not enough room for a Vendor-Id.
3543 * Or the high octet of the Vendor-Id is set.
3545 if ((data[1] < 6) || (data[2] != 0)) {
3546 return rad_attr2vp_raw(packet, original, secret,
3550 memcpy(&lvalue, data + 2, 4);
3551 lvalue = ntohl(lvalue);
3554 * WiMAX gets its own set of magic.
3556 if (lvalue == VENDORPEC_WIMAX) {
3558 return rad_attr2vp_wimax(packet, original, secret,
3562 dv_type = dv_length = 1;
3563 dv = dict_vendorbyvalue(lvalue);
3566 dv_length = dv->length;
3568 if (dv->flags) goto wimax;
3572 * Attribute is not in the correct form.
3574 if (rad_tlv_ok(data + 6, data[1] - 6, dv_type, dv_length) < 0) {
3575 return rad_attr2vp_raw(packet, original, secret,
3579 my_len = attr2vp_vsa(packet, original, secret,
3580 lvalue, dv_type, dv_length,
3581 data + 6, data[1] - 6, pvp);
3582 if (my_len < 0) return my_len;
3585 * Incomplete decode means that something is wrong
3586 * with the attribute. Back up, and make it "raw".
3588 if (my_len != (data[1] - 6)) {
3590 return rad_attr2vp_raw(packet, original, secret,
3598 * Create an "extended" VALUE_PAIR from a RADIUS attribute.
3600 ssize_t rad_attr2vp_extended(const RADIUS_PACKET *packet,
3601 const RADIUS_PACKET *original,
3603 const uint8_t *start, size_t length,
3606 unsigned int attribute;
3609 unsigned int vendor = VENDORPEC_EXTENDED;
3610 size_t data_len = length;
3611 const uint8_t *data;
3616 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3617 fr_strerror_printf("rad_attr2vp_extended: Invalid length");
3621 da = dict_attrbyvalue(data[0], vendor);
3623 (!da->flags.extended && !da->flags.extended_flags)) {
3624 fr_strerror_printf("rad_attr2vp_extended: Attribute is not extended format");
3631 * No Extended-Type. It's a raw attribute.
3632 * Also, if there's no data following the Extended-Type,
3633 * it's a raw attribute.
3637 return rad_attr2vp_raw(packet, original, secret, start,
3642 * The attribute is "241.1", for example. Go look that
3643 * up to see what type it is.
3645 attribute = data[0];
3646 attribute |= (data[2] << fr_attr_shift[1]);
3648 da = dict_attrbyvalue(attribute, vendor);
3651 vendor = VENDORPEC_EXTENDED;
3654 if (data[1] < length) data_len = data[1];
3660 * If there's supposed to be a flag octet. If not, it's
3661 * a raw attribute. If the flag is set, it's supposed to
3664 if (da->flags.extended_flags) {
3665 if (data_len == 0) goto raw;
3667 continued = ((data[0] & 0x80) != 0);
3673 * Extended VSAs have 4 octets of
3674 * Vendor-Id followed by one octet of
3677 if (da->flags.evs) {
3678 if (data_len < 5) goto raw;
3681 * Vendor Ids can only be 24-bit.
3683 if (data[0] != 0) goto raw;
3685 vendor = ((data[1] << 16) |
3690 * Pack the *encapsulating* attribute number into
3691 * the vendor id. This number should be >= 241.
3693 vendor |= start[0] * FR_MAX_VENDOR;
3697 * Over-write the attribute with the
3700 attribute = data[4];
3706 int first_offset = 4;
3709 if (vendor != VENDORPEC_EXTENDED) first_offset += 5;
3711 my_len = extended_attrlen(start, start + length);
3712 if (my_len < 0) goto raw;
3714 if (vendor != VENDORPEC_EXTENDED) my_len -= 5;
3716 return data2vp_continued(packet, original, secret,
3717 start, length, pvp, shift,
3719 first_offset, 4, my_len);
3722 if (data2vp_any(packet, original, secret, shift,
3723 attribute, vendor, data, data_len, pvp) < 0) {
3727 return (data + data_len) - start;
3732 * Create a "standard" RFC VALUE_PAIR from the given data.
3734 ssize_t rad_attr2vp_rfc(const RADIUS_PACKET *packet,
3735 const RADIUS_PACKET *original,
3737 const uint8_t *data, size_t length,
3740 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3741 fr_strerror_printf("rad_attr2vp_rfc: Insufficient data");
3745 if (data2vp_any(packet, original, secret, 0,
3746 data[0], 0, data + 2, data[1] - 2, pvp) < 0) {
3754 * Create a "normal" VALUE_PAIR from the given data.
3756 ssize_t rad_attr2vp(const RADIUS_PACKET *packet,
3757 const RADIUS_PACKET *original,
3759 const uint8_t *data, size_t length,
3762 if ((length < 2) || (data[1] < 2) || (data[1] > length)) {
3763 fr_strerror_printf("rad_attr2vp: Insufficient data");
3768 * VSAs get their own handler.
3770 if (data[0] == PW_VENDOR_SPECIFIC) {
3771 return rad_attr2vp_vsa(packet, original, secret,
3776 * Extended attribute format gets their own handler.
3778 if (dict_attrbyvalue(data[0], VENDORPEC_EXTENDED) != NULL) {
3779 return rad_attr2vp_extended(packet, original, secret,
3783 return rad_attr2vp_rfc(packet, original, secret, data, length, pvp);
3788 * Calculate/check digest, and decode radius attributes.
3790 * -1 on decoding error
3793 int rad_decode(RADIUS_PACKET *packet, RADIUS_PACKET *original,
3799 radius_packet_t *hdr;
3800 VALUE_PAIR *head, **tail, *vp;
3803 * Extract attribute-value pairs
3805 hdr = (radius_packet_t *)packet->data;
3807 packet_length = packet->data_len - AUTH_HDR_LEN;
3814 * Loop over the attributes, decoding them into VPs.
3816 while (packet_length > 0) {
3820 * This may return many VPs
3822 my_len = rad_attr2vp(packet, original, secret,
3823 ptr, packet_length, &vp);
3838 * VSA's may not have been counted properly in
3839 * rad_packet_ok() above, as it is hard to count
3840 * then without using the dictionary. We
3841 * therefore enforce the limits here, too.
3843 if ((fr_max_attributes > 0) &&
3844 (num_attributes > fr_max_attributes)) {
3845 char host_ipaddr[128];
3848 fr_strerror_printf("WARNING: Possible DoS attack from host %s: Too many attributes in request (received %d, max %d are allowed).",
3849 inet_ntop(packet->src_ipaddr.af,
3850 &packet->src_ipaddr.ipaddr,
3851 host_ipaddr, sizeof(host_ipaddr)),
3852 num_attributes, fr_max_attributes);
3857 packet_length -= my_len;
3861 * Merge information from the outside world into our
3864 fr_rand_seed(packet->data, AUTH_HDR_LEN);
3867 * There may be VP's already in the packet. Don't
3868 * destroy them. Instead, add the decoded attributes to
3869 * the tail of the list.
3871 for (tail = &packet->vps; *tail != NULL; tail = &((*tail)->next)) {
3883 * We assume that the passwd buffer passed is big enough.
3884 * RFC2138 says the password is max 128 chars, so the size
3885 * of the passwd buffer must be at least 129 characters.
3886 * Preferably it's just MAX_STRING_LEN.
3888 * int *pwlen is updated to the new length of the encrypted
3889 * password - a multiple of 16 bytes.
3891 int rad_pwencode(char *passwd, size_t *pwlen, const char *secret,
3892 const uint8_t *vector)
3894 FR_MD5_CTX context, old;
3895 uint8_t digest[AUTH_VECTOR_LEN];
3896 int i, n, secretlen;
3900 * RFC maximum is 128 bytes.
3902 * If length is zero, pad it out with zeros.
3904 * If the length isn't aligned to 16 bytes,
3905 * zero out the extra data.
3909 if (len > 128) len = 128;
3912 memset(passwd, 0, AUTH_PASS_LEN);
3913 len = AUTH_PASS_LEN;
3914 } else if ((len % AUTH_PASS_LEN) != 0) {
3915 memset(&passwd[len], 0, AUTH_PASS_LEN - (len % AUTH_PASS_LEN));
3916 len += AUTH_PASS_LEN - (len % AUTH_PASS_LEN);
3921 * Use the secret to setup the decryption digest
3923 secretlen = strlen(secret);
3925 fr_MD5Init(&context);
3926 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3927 old = context; /* save intermediate work */
3930 * Encrypt it in place. Don't bother checking
3931 * len, as we've ensured above that it's OK.
3933 for (n = 0; n < len; n += AUTH_PASS_LEN) {
3935 fr_MD5Update(&context, vector, AUTH_PASS_LEN);
3936 fr_MD5Final(digest, &context);
3939 fr_MD5Update(&context,
3940 (uint8_t *) passwd + n - AUTH_PASS_LEN,
3942 fr_MD5Final(digest, &context);
3945 for (i = 0; i < AUTH_PASS_LEN; i++) {
3946 passwd[i + n] ^= digest[i];
3956 int rad_pwdecode(char *passwd, size_t pwlen, const char *secret,
3957 const uint8_t *vector)
3959 FR_MD5_CTX context, old;
3960 uint8_t digest[AUTH_VECTOR_LEN];
3962 size_t n, secretlen;
3965 * The RFC's say that the maximum is 128.
3966 * The buffer we're putting it into above is 254, so
3967 * we don't need to do any length checking.
3969 if (pwlen > 128) pwlen = 128;
3974 if (pwlen == 0) goto done;
3977 * Use the secret to setup the decryption digest
3979 secretlen = strlen(secret);
3981 fr_MD5Init(&context);
3982 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
3983 old = context; /* save intermediate work */
3986 * The inverse of the code above.
3988 for (n = 0; n < pwlen; n += AUTH_PASS_LEN) {
3990 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
3991 fr_MD5Final(digest, &context);
3994 if (pwlen > AUTH_PASS_LEN) {
3995 fr_MD5Update(&context, (uint8_t *) passwd,
3999 fr_MD5Final(digest, &context);
4002 if (pwlen > (n + AUTH_PASS_LEN)) {
4003 fr_MD5Update(&context, (uint8_t *) passwd + n,
4008 for (i = 0; i < AUTH_PASS_LEN; i++) {
4009 passwd[i + n] ^= digest[i];
4014 passwd[pwlen] = '\0';
4015 return strlen(passwd);
4020 * Encode Tunnel-Password attributes when sending them out on the wire.
4022 * int *pwlen is updated to the new length of the encrypted
4023 * password - a multiple of 16 bytes.
4025 * This is per RFC-2868 which adds a two char SALT to the initial intermediate
4028 int rad_tunnel_pwencode(char *passwd, size_t *pwlen, const char *secret,
4029 const uint8_t *vector)
4031 uint8_t buffer[AUTH_VECTOR_LEN + MAX_STRING_LEN + 3];
4032 unsigned char digest[AUTH_VECTOR_LEN];
4034 int i, n, secretlen;
4039 if (len > 127) len = 127;
4042 * Shift the password 3 positions right to place a salt and original
4043 * length, tag will be added automatically on packet send
4045 for (n=len ; n>=0 ; n--) passwd[n+3] = passwd[n];
4049 * save original password length as first password character;
4056 * Generate salt. The RFC's say:
4058 * The high bit of salt[0] must be set, each salt in a
4059 * packet should be unique, and they should be random
4061 * So, we set the high bit, add in a counter, and then
4062 * add in some CSPRNG data. should be OK..
4064 salt[0] = (0x80 | ( ((salt_offset++) & 0x0f) << 3) |
4065 (fr_rand() & 0x07));
4066 salt[1] = fr_rand();
4069 * Padd password to multiple of AUTH_PASS_LEN bytes.
4071 n = len % AUTH_PASS_LEN;
4073 n = AUTH_PASS_LEN - n;
4074 for (; n > 0; n--, len++)
4077 /* set new password length */
4081 * Use the secret to setup the decryption digest
4083 secretlen = strlen(secret);
4084 memcpy(buffer, secret, secretlen);
4086 for (n2 = 0; n2 < len; n2+=AUTH_PASS_LEN) {
4088 memcpy(buffer + secretlen, vector, AUTH_VECTOR_LEN);
4089 memcpy(buffer + secretlen + AUTH_VECTOR_LEN, salt, 2);
4090 fr_md5_calc(digest, buffer, secretlen + AUTH_VECTOR_LEN + 2);
4092 memcpy(buffer + secretlen, passwd + n2 - AUTH_PASS_LEN, AUTH_PASS_LEN);
4093 fr_md5_calc(digest, buffer, secretlen + AUTH_PASS_LEN);
4096 for (i = 0; i < AUTH_PASS_LEN; i++) {
4097 passwd[i + n2] ^= digest[i];
4105 * Decode Tunnel-Password encrypted attributes.
4107 * Defined in RFC-2868, this uses a two char SALT along with the
4108 * initial intermediate value, to differentiate it from the
4111 int rad_tunnel_pwdecode(uint8_t *passwd, size_t *pwlen, const char *secret,
4112 const uint8_t *vector)
4114 FR_MD5_CTX context, old;
4115 uint8_t digest[AUTH_VECTOR_LEN];
4117 unsigned i, n, len, reallen;
4122 * We need at least a salt.
4125 fr_strerror_printf("tunnel password is too short");
4130 * There's a salt, but no password. Or, there's a salt
4131 * and a 'data_len' octet. It's wrong, but at least we
4132 * can figure out what it means: the password is empty.
4134 * Note that this means we ignore the 'data_len' field,
4135 * if the attribute length tells us that there's no
4136 * more data. So the 'data_len' field may be wrong,
4145 len -= 2; /* discount the salt */
4148 * Use the secret to setup the decryption digest
4150 secretlen = strlen(secret);
4152 fr_MD5Init(&context);
4153 fr_MD5Update(&context, (const uint8_t *) secret, secretlen);
4154 old = context; /* save intermediate work */
4157 * Set up the initial key:
4159 * b(1) = MD5(secret + vector + salt)
4161 fr_MD5Update(&context, vector, AUTH_VECTOR_LEN);
4162 fr_MD5Update(&context, passwd, 2);
4165 for (n = 0; n < len; n += AUTH_PASS_LEN) {
4169 fr_MD5Final(digest, &context);
4174 * A quick check: decrypt the first octet
4175 * of the password, which is the
4176 * 'data_len' field. Ensure it's sane.
4178 reallen = passwd[2] ^ digest[0];
4179 if (reallen >= len) {
4180 fr_strerror_printf("tunnel password is too long for the attribute");
4184 fr_MD5Update(&context, passwd + 2, AUTH_PASS_LEN);
4188 fr_MD5Final(digest, &context);
4191 fr_MD5Update(&context, passwd + n + 2, AUTH_PASS_LEN);
4194 for (i = base; i < AUTH_PASS_LEN; i++) {
4195 passwd[n + i - 1] = passwd[n + i + 2] ^ digest[i];
4200 * See make_tunnel_password, above.
4202 if (reallen > 239) reallen = 239;
4205 passwd[reallen] = 0;
4211 * Encode a CHAP password
4213 * FIXME: might not work with Ascend because
4214 * we use vp->length, and Ascend gear likes
4215 * to send an extra '\0' in the string!
4217 int rad_chap_encode(RADIUS_PACKET *packet, uint8_t *output, int id,
4218 VALUE_PAIR *password)
4222 uint8_t string[MAX_STRING_LEN * 2 + 1];
4223 VALUE_PAIR *challenge;
4226 * Sanity check the input parameters
4228 if ((packet == NULL) || (password == NULL)) {
4233 * Note that the password VP can be EITHER
4234 * a User-Password attribute (from a check-item list),
4235 * or a CHAP-Password attribute (the client asking
4236 * the library to encode it).
4244 memcpy(ptr, password->vp_strvalue, password->length);
4245 ptr += password->length;
4246 i += password->length;
4249 * Use Chap-Challenge pair if present,
4250 * Request-Authenticator otherwise.
4252 challenge = pairfind(packet->vps, PW_CHAP_CHALLENGE, 0);
4254 memcpy(ptr, challenge->vp_strvalue, challenge->length);
4255 i += challenge->length;
4257 memcpy(ptr, packet->vector, AUTH_VECTOR_LEN);
4258 i += AUTH_VECTOR_LEN;
4262 fr_md5_calc((uint8_t *)output + 1, (uint8_t *)string, i);
4269 * Seed the random number generator.
4271 * May be called any number of times.
4273 void fr_rand_seed(const void *data, size_t size)
4278 * Ensure that the pool is initialized.
4280 if (!fr_rand_initialized) {
4283 memset(&fr_rand_pool, 0, sizeof(fr_rand_pool));
4285 fd = open("/dev/urandom", O_RDONLY);
4291 while (total < sizeof(fr_rand_pool.randrsl)) {
4292 this = read(fd, fr_rand_pool.randrsl,
4293 sizeof(fr_rand_pool.randrsl) - total);
4294 if ((this < 0) && (errno != EINTR)) break;
4295 if (this > 0) total += this;
4299 fr_rand_pool.randrsl[0] = fd;
4300 fr_rand_pool.randrsl[1] = time(NULL);
4301 fr_rand_pool.randrsl[2] = errno;
4304 fr_randinit(&fr_rand_pool, 1);
4305 fr_rand_pool.randcnt = 0;
4306 fr_rand_initialized = 1;
4312 * Hash the user data
4315 if (!hash) hash = fr_rand();
4316 hash = fr_hash_update(data, size, hash);
4318 fr_rand_pool.randmem[fr_rand_pool.randcnt] ^= hash;
4323 * Return a 32-bit random number.
4325 uint32_t fr_rand(void)
4330 * Ensure that the pool is initialized.
4332 if (!fr_rand_initialized) {
4333 fr_rand_seed(NULL, 0);
4336 num = fr_rand_pool.randrsl[fr_rand_pool.randcnt++];
4337 if (fr_rand_pool.randcnt >= 256) {
4338 fr_rand_pool.randcnt = 0;
4339 fr_isaac(&fr_rand_pool);
4347 * Allocate a new RADIUS_PACKET
4349 RADIUS_PACKET *rad_alloc(int newvector)
4353 if ((rp = malloc(sizeof(RADIUS_PACKET))) == NULL) {
4354 fr_strerror_printf("out of memory");
4357 memset(rp, 0, sizeof(*rp));
4363 uint32_t hash, base;
4366 * Don't expose the actual contents of the random
4370 for (i = 0; i < AUTH_VECTOR_LEN; i += sizeof(uint32_t)) {
4371 hash = fr_rand() ^ base;
4372 memcpy(rp->vector + i, &hash, sizeof(hash));
4375 fr_rand(); /* stir the pool again */
4380 RADIUS_PACKET *rad_alloc_reply(RADIUS_PACKET *packet)
4382 RADIUS_PACKET *reply;
4384 if (!packet) return NULL;
4386 reply = rad_alloc(0);
4387 if (!reply) return NULL;
4390 * Initialize the fields from the request.
4392 reply->sockfd = packet->sockfd;
4393 reply->dst_ipaddr = packet->src_ipaddr;
4394 reply->src_ipaddr = packet->dst_ipaddr;
4395 reply->dst_port = packet->src_port;
4396 reply->src_port = packet->dst_port;
4397 reply->id = packet->id;
4398 reply->code = 0; /* UNKNOWN code */
4399 memcpy(reply->vector, packet->vector,
4400 sizeof(reply->vector));
4403 reply->data_len = 0;
4410 * Free a RADIUS_PACKET
4412 void rad_free(RADIUS_PACKET **radius_packet_ptr)
4414 RADIUS_PACKET *radius_packet;
4416 if (!radius_packet_ptr || !*radius_packet_ptr) return;
4417 radius_packet = *radius_packet_ptr;
4419 free(radius_packet->data);
4421 pairfree(&radius_packet->vps);
4423 free(radius_packet);
4425 *radius_packet_ptr = NULL;