2 * dhcp.c Functions to send/receive dhcp 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 2008 The FreeRADIUS server project
21 * Copyright 2008 Alan DeKok <aland@deployingradius.com>
26 #include <freeradius-devel/libradius.h>
27 #include <freeradius-devel/udpfromto.h>
28 #include <freeradius-devel/dhcp.h>
31 #include <sys/ioctl.h>
34 #ifdef HAVE_SYS_SOCKET_H
35 #include <sys/socket.h>
37 #ifdef HAVE_SYS_TYPES_H
38 #include <sys/types.h>
42 #include <net/if_arp.h>
45 #define DHCP_CHADDR_LEN (16)
46 #define DHCP_SNAME_LEN (64)
47 #define DHCP_FILE_LEN (128)
48 #define DHCP_VEND_LEN (308)
49 #define DHCP_OPTION_MAGIC_NUMBER (0x63825363)
51 #ifndef INADDR_BROADCAST
52 #define INADDR_BROADCAST INADDR_NONE
55 /* @todo: this is a hack */
56 # define DEBUG if (fr_debug_flag && fr_log_fp) fr_printf_log
57 void fr_strerror_printf(char const *fmt, ...);
58 # define debug_pair(vp) do { if (fr_debug_flag && fr_log_fp) { \
59 vp_print(fr_log_fp, vp); \
63 typedef struct dhcp_packet_t {
69 uint16_t secs; /* 8 */
71 uint32_t ciaddr; /* 12 */
72 uint32_t yiaddr; /* 16 */
73 uint32_t siaddr; /* 20 */
74 uint32_t giaddr; /* 24 */
75 uint8_t chaddr[DHCP_CHADDR_LEN]; /* 28 */
76 uint8_t sname[DHCP_SNAME_LEN]; /* 44 */
77 uint8_t file[DHCP_FILE_LEN]; /* 108 */
78 uint32_t option_format; /* 236 */
79 uint8_t options[DHCP_VEND_LEN];
82 typedef struct dhcp_option_t {
88 * INADDR_ANY : 68 -> INADDR_BROADCAST : 67 DISCOVER
89 * INADDR_BROADCAST : 68 <- SERVER_IP : 67 OFFER
90 * INADDR_ANY : 68 -> INADDR_BROADCAST : 67 REQUEST
91 * INADDR_BROADCAST : 68 <- SERVER_IP : 67 ACK
93 static char const *dhcp_header_names[] = {
96 "DHCP-Hardware-Address-Length",
98 "DHCP-Transaction-Id",
99 "DHCP-Number-of-Seconds",
101 "DHCP-Client-IP-Address",
102 "DHCP-Your-IP-Address",
103 "DHCP-Server-IP-Address",
104 "DHCP-Gateway-IP-Address",
105 "DHCP-Client-Hardware-Address",
106 "DHCP-Server-Host-Name",
107 "DHCP-Boot-Filename",
112 static char const *dhcp_message_types[] = {
125 static int dhcp_header_sizes[] = {
136 * Some clients silently ignore responses less than 300 bytes.
138 #define MIN_PACKET_SIZE (244)
139 #define DEFAULT_PACKET_SIZE (300)
140 #define MAX_PACKET_SIZE (1500 - 40)
142 #define DHCP_OPTION_FIELD (0)
143 #define DHCP_FILE_FIELD (1)
144 #define DHCP_SNAME_FIELD (2)
146 static uint8_t *dhcp_get_option(dhcp_packet_t *packet, size_t packet_size,
150 int field = DHCP_OPTION_FIELD;
155 size = packet_size - offsetof(dhcp_packet_t, options);
156 data = &packet->options[where];
158 while (where < size) {
159 if (data[0] == 0) { /* padding */
164 if (data[0] == 255) { /* end of options */
165 if ((field == DHCP_OPTION_FIELD) &&
166 (overload & DHCP_FILE_FIELD)) {
169 size = sizeof(packet->file);
170 field = DHCP_FILE_FIELD;
173 } else if ((field == DHCP_FILE_FIELD) &&
174 (overload & DHCP_SNAME_FIELD)) {
175 data = packet->sname;
177 size = sizeof(packet->sname);
178 field = DHCP_SNAME_FIELD;
186 * We MUST have a real option here.
188 if ((where + 2) > size) {
189 fr_strerror_printf("Options overflow field at %u",
190 (unsigned int) (data - (uint8_t *) packet));
194 if ((where + 2 + data[1]) > size) {
195 fr_strerror_printf("Option length overflows field at %u",
196 (unsigned int) (data - (uint8_t *) packet));
200 if (data[0] == option) return data;
202 if (data[0] == 52) { /* overload sname and/or file */
206 where += data[1] + 2;
214 * DHCPv4 is only for IPv4. Broadcast only works if udpfromto is
217 RADIUS_PACKET *fr_dhcp_recv(int sockfd)
220 struct sockaddr_storage src;
221 struct sockaddr_storage dst;
222 socklen_t sizeof_src;
223 socklen_t sizeof_dst;
224 RADIUS_PACKET *packet;
229 packet = rad_alloc(NULL, 0);
231 fr_strerror_printf("Failed allocating packet");
235 packet->data = talloc_zero_array(packet, uint8_t, MAX_PACKET_SIZE);
237 fr_strerror_printf("Out of memory");
242 packet->sockfd = sockfd;
243 sizeof_src = sizeof(src);
244 #ifdef WITH_UDPFROMTO
245 sizeof_dst = sizeof(dst);
246 data_len = recvfromto(sockfd, packet->data, MAX_PACKET_SIZE, 0,
247 (struct sockaddr *)&src, &sizeof_src,
248 (struct sockaddr *)&dst, &sizeof_dst);
250 data_len = recvfrom(sockfd, packet->data, MAX_PACKET_SIZE, 0,
251 (struct sockaddr *)&src, &sizeof_src);
255 fr_strerror_printf("Failed reading DHCP socket: %s", fr_syserror(errno));
260 packet->data_len = data_len;
261 if (packet->data_len < MIN_PACKET_SIZE) {
262 fr_strerror_printf("DHCP packet is too small (%zu < %d)",
263 packet->data_len, MIN_PACKET_SIZE);
268 if (packet->data_len > MAX_PACKET_SIZE) {
269 fr_strerror_printf("DHCP packet is too large (%zx > %d)",
270 packet->data_len, MAX_PACKET_SIZE);
275 if (packet->data[1] != 1) {
276 fr_strerror_printf("DHCP can only receive ethernet requests, not type %02x",
282 if (packet->data[2] != 6) {
283 fr_strerror_printf("Ethernet HW length is wrong length %d",
289 memcpy(&magic, packet->data + 236, 4);
290 magic = ntohl(magic);
291 if (magic != DHCP_OPTION_MAGIC_NUMBER) {
292 fr_strerror_printf("Cannot do BOOTP");
298 * Create unique keys for the packet.
300 memcpy(&magic, packet->data + 4, 4);
301 packet->id = ntohl(magic);
303 code = dhcp_get_option((dhcp_packet_t *) packet->data,
304 packet->data_len, 53);
306 fr_strerror_printf("No message-type option was found in the packet");
311 if ((code[1] < 1) || (code[2] == 0) || (code[2] > 8)) {
312 fr_strerror_printf("Unknown value for message-type option");
317 packet->code = code[2] | PW_DHCP_OFFSET;
320 * Create a unique vector from the MAC address and the
321 * DHCP opcode. This is a hack for the RADIUS
322 * infrastructure in the rest of the server.
324 * Note: packet->data[2] == 6, which is smaller than
325 * sizeof(packet->vector)
327 * FIXME: Look for client-identifier in packet,
330 memset(packet->vector, 0, sizeof(packet->vector));
331 memcpy(packet->vector, packet->data + 28, packet->data[2]);
332 packet->vector[packet->data[2]] = packet->code & 0xff;
335 * FIXME: for DISCOVER / REQUEST: src_port == dst_port + 1
336 * FIXME: for OFFER / ACK : src_port = dst_port - 1
340 * Unique keys are xid, client mac, and client ID?
344 * FIXME: More checks, like DHCP packet type?
347 sizeof_dst = sizeof(dst);
349 #ifndef WITH_UDPFROMTO
351 * This should never fail...
353 if (getsockname(sockfd, (struct sockaddr *) &dst, &sizeof_dst) < 0) {
354 fr_strerror_printf("getsockname failed: %s", fr_syserror(errno));
360 fr_sockaddr2ipaddr(&dst, sizeof_dst, &packet->dst_ipaddr, &port);
361 packet->dst_port = port;
363 fr_sockaddr2ipaddr(&src, sizeof_src, &packet->src_ipaddr, &port);
364 packet->src_port = port;
366 if (fr_debug_flag > 1) {
368 char const *name = type_buf;
369 char src_ip_buf[256], dst_ip_buf[256];
371 if ((packet->code >= PW_DHCP_DISCOVER) &&
372 (packet->code <= PW_DHCP_INFORM)) {
373 name = dhcp_message_types[packet->code - PW_DHCP_OFFSET];
375 snprintf(type_buf, sizeof(type_buf), "%d",
376 packet->code - PW_DHCP_OFFSET);
379 DEBUG("Received %s of id %08x from %s:%d to %s:%d\n",
380 name, (unsigned int) packet->id,
381 inet_ntop(packet->src_ipaddr.af,
382 &packet->src_ipaddr.ipaddr,
383 src_ip_buf, sizeof(src_ip_buf)),
385 inet_ntop(packet->dst_ipaddr.af,
386 &packet->dst_ipaddr.ipaddr,
387 dst_ip_buf, sizeof(dst_ip_buf)),
396 * Send a DHCP packet.
398 int fr_dhcp_send(RADIUS_PACKET *packet)
400 struct sockaddr_storage dst;
401 socklen_t sizeof_dst;
402 #ifdef WITH_UDPFROMTO
403 struct sockaddr_storage src;
404 socklen_t sizeof_src;
406 fr_ipaddr2sockaddr(&packet->src_ipaddr, packet->src_port,
410 fr_ipaddr2sockaddr(&packet->dst_ipaddr, packet->dst_port,
413 if (packet->data_len == 0) {
414 fr_strerror_printf("No data to send");
418 if (fr_debug_flag > 1) {
420 char const *name = type_buf;
421 #ifdef WITH_UDPFROMTO
422 char src_ip_buf[INET6_ADDRSTRLEN];
424 char dst_ip_buf[INET6_ADDRSTRLEN];
426 if ((packet->code >= PW_DHCP_DISCOVER) &&
427 (packet->code <= PW_DHCP_INFORM)) {
428 name = dhcp_message_types[packet->code - PW_DHCP_OFFSET];
430 snprintf(type_buf, sizeof(type_buf), "%d",
431 packet->code - PW_DHCP_OFFSET);
435 #ifdef WITH_UDPFROMTO
436 "Sending %s of id %08x from %s:%d to %s:%d\n",
438 "Sending %s of id %08x to %s:%d\n",
440 name, (unsigned int) packet->id,
441 #ifdef WITH_UDPFROMTO
442 inet_ntop(packet->src_ipaddr.af, &packet->src_ipaddr.ipaddr, src_ip_buf, sizeof(src_ip_buf)),
445 inet_ntop(packet->dst_ipaddr.af, &packet->dst_ipaddr.ipaddr, dst_ip_buf, sizeof(dst_ip_buf)),
449 #ifndef WITH_UDPFROMTO
451 * Assume that the packet is encoded before sending it.
453 return sendto(packet->sockfd, packet->data, packet->data_len, 0,
454 (struct sockaddr *)&dst, sizeof_dst);
457 return sendfromto(packet->sockfd, packet->data, packet->data_len, 0,
458 (struct sockaddr *)&src, sizeof_src,
459 (struct sockaddr *)&dst, sizeof_dst);
463 static int fr_dhcp_attr2vp(RADIUS_PACKET *packet, VALUE_PAIR *vp, uint8_t const *p, size_t alen);
465 static int decode_tlv(RADIUS_PACKET *packet, VALUE_PAIR *tlv, uint8_t const *data, size_t data_len)
468 VALUE_PAIR *head, *vp;
472 * Take a pass at parsing it.
475 while (p < (data + data_len)) {
476 if ((p + 2) > (data + data_len)) goto make_tlv;
478 if ((p + p[1] + 2) > (data + data_len)) goto make_tlv;
483 * Got here... must be well formed.
486 fr_cursor_init(&cursor, &head);
489 while (p < (data + data_len)) {
490 vp = paircreate(packet, tlv->da->attr | (p[0] << 8), DHCP_MAGIC_VENDOR);
496 if (fr_dhcp_attr2vp(packet, vp, p + 2, p[1]) < 0) {
501 fr_cursor_insert(&cursor, vp);
506 * The caller allocated TLV, so we need to copy the FIRST
507 * attribute over top of that.
509 * This is a pretty awful hack, but we should be able to
510 * clean it up when we get nested VPs so lets leave it for
514 /* Cleanup any old TLV data */
515 talloc_free(tlv->vp_tlv);
518 memcpy(tlv, head, sizeof(*tlv));
520 /* If the VP has a talloced value we need to reparent it to the original TLV attribute */
521 switch (head->da->type) {
525 talloc_steal(tlv, head->data.ptr);
529 tlv->next = head->next;
536 tlv->vp_tlv = talloc_array(tlv, uint8_t, data_len);
538 fr_strerror_printf("No memory");
541 memcpy(tlv->vp_tlv, data, data_len);
542 tlv->length = data_len;
549 * Decode ONE value into a VP
551 static int fr_dhcp_attr2vp(RADIUS_PACKET *packet, VALUE_PAIR *vp, uint8_t const *p, size_t alen)
555 switch (vp->da->type) {
557 if (alen != 1) goto raw;
558 vp->vp_integer = p[0];
562 if (alen != 2) goto raw;
563 memcpy(&vp->vp_integer, p, 2);
564 vp->vp_integer = ntohs(vp->vp_integer);
567 case PW_TYPE_INTEGER:
568 if (alen != 4) goto raw;
569 memcpy(&vp->vp_integer, p, 4);
570 vp->vp_integer = ntohl(vp->vp_integer);
574 if (alen != 4) goto raw;
576 * Keep value in Network Order!
578 memcpy(&vp->vp_ipaddr, p , 4);
583 vp->vp_strvalue = q = talloc_array(vp, char, alen + 1);
589 case PW_TYPE_ETHERNET:
590 memcpy(vp->vp_ether, p, sizeof(vp->vp_ether));
591 vp->length = sizeof(vp->vp_ether);
595 * Value doesn't match up with attribute type, overwrite the
596 * vp's original DICT_ATTR with an unknown one.
599 if (pair2unknown(vp) < 0) return -1;
602 if (alen > 253) return -1;
603 pairmemcpy(vp, p, alen);
607 return decode_tlv(packet, vp, p, alen);
610 fr_strerror_printf("Internal sanity check %d %d", vp->da->type, __LINE__);
612 } /* switch over type */
618 ssize_t fr_dhcp_decode_options(RADIUS_PACKET *packet,
619 uint8_t const *data, size_t len, VALUE_PAIR **head)
624 uint8_t const *p, *next;
628 fr_cursor_init(&cursor, head);
631 * FIXME: This should also check sname && file fields.
632 * See the dhcp_get_option() function above.
634 while (next < (data + len)) {
635 int num_entries, alen;
641 if (*p == 255) break; /* end of options signifier */
642 if ((p + 2) > (data + len)) break;
647 fr_strerror_printf("Attribute too long %u %u",
652 da = dict_attrbyvalue(p[0], DHCP_MAGIC_VENDOR);
654 fr_strerror_printf("Attribute not in our dictionary: %u",
665 * Could be an array of bytes, integers, etc.
667 if (da->flags.array) {
674 case PW_TYPE_SHORT: /* ignore any trailing data */
675 num_entries = alen >> 1;
680 case PW_TYPE_INTEGER:
681 case PW_TYPE_DATE: /* ignore any trailing data */
682 num_entries = alen >> 2;
688 break; /* really an internal sanity failure */
693 * Loop over all of the entries, building VPs
695 for (i = 0; i < num_entries; i++) {
696 vp = pairmake(packet, NULL, da->name, NULL, T_OP_ADD);
698 fr_strerror_printf("Cannot build attribute %s",
705 * Hack for ease of use.
707 if ((da->vendor == DHCP_MAGIC_VENDOR) &&
708 (da->attr == 61) && !da->flags.array &&
709 (alen == 7) && (*p == 1) && (num_entries == 1)) {
710 pairmemcpy(vp, p + 1, 6);
712 } else if (fr_dhcp_attr2vp(packet, vp, p, alen) < 0) {
718 fr_cursor_insert(&cursor, vp);
720 for (vp = fr_cursor_current(&cursor);
722 vp = fr_cursor_next(&cursor)) {
726 } /* loop over array entries */
727 } /* loop over the entire packet */
732 int fr_dhcp_decode(RADIUS_PACKET *packet)
738 VALUE_PAIR *head = NULL, *vp;
739 VALUE_PAIR *maxms, *mtu;
741 fr_cursor_init(&cursor, &head);
744 if ((fr_debug_flag > 2) && fr_log_fp) {
745 for (i = 0; i < packet->data_len; i++) {
746 if ((i & 0x0f) == 0x00) fprintf(fr_log_fp, "%d: ", (int) i);
747 fprintf(fr_log_fp, "%02x ", packet->data[i]);
748 if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
750 fprintf(fr_log_fp, "\n");
753 if (packet->data[1] != 1) {
754 fr_strerror_printf("Packet is not Ethernet: %u",
762 for (i = 0; i < 14; i++) {
765 vp = pairmake(packet, NULL, dhcp_header_names[i], NULL, T_OP_EQ);
768 strlcpy(buffer, fr_strerror(), sizeof(buffer));
769 fr_strerror_printf("Cannot decode packet due to internal error: %s", buffer);
775 * If chaddr does != 6 bytes it's probably not ethernet, and we should store
776 * it as an opaque type (octets).
778 if ((i == 11) && (packet->data[1] == 1) && (packet->data[2] != sizeof(vp->vp_ether))) {
779 DICT_ATTR const *da = dict_attrunknown(vp->da->attr, vp->da->vendor, true);
786 switch (vp->da->type) {
788 vp->vp_integer = p[0];
793 vp->vp_integer = (p[0] << 8) | p[1];
797 case PW_TYPE_INTEGER:
798 memcpy(&vp->vp_integer, p, 4);
799 vp->vp_integer = ntohl(vp->vp_integer);
804 memcpy(&vp->vp_ipaddr, p, 4);
809 vp->vp_strvalue = q = talloc_array(vp, char, dhcp_header_sizes[i] + 1);
811 memcpy(q, p, dhcp_header_sizes[i]);
812 q[dhcp_header_sizes[i]] = '\0';
813 vp->length = strlen(vp->vp_strvalue);
814 if (vp->length == 0) {
820 pairmemcpy(vp, p, packet->data[2]);
823 case PW_TYPE_ETHERNET:
824 memcpy(vp->vp_ether, p, sizeof(vp->vp_ether));
825 vp->length = sizeof(vp->vp_ether);
829 fr_strerror_printf("BAD TYPE %d", vp->da->type);
833 p += dhcp_header_sizes[i];
838 fr_cursor_insert(&cursor, vp);
842 * Loop over the options.
846 * Nothing uses tail after this call, if it does in the future
847 * it'll need to find the new tail...
850 VALUE_PAIR *options = NULL;
852 if (fr_dhcp_decode_options(packet,
853 packet->data + 240, packet->data_len - 240,
859 fr_cursor_insert(&cursor, options);
864 * If DHCP request, set ciaddr to zero.
868 * Set broadcast flag for broken vendors, but only if
871 memcpy(&giaddr, packet->data + 24, sizeof(giaddr));
872 if (giaddr == htonl(INADDR_ANY)) {
874 * DHCP Opcode is request
876 vp = pairfind(head, 256, DHCP_MAGIC_VENDOR, TAG_ANY);
877 if (vp && vp->vp_integer == 3) {
879 * Vendor is "MSFT 98"
881 vp = pairfind(head, 63, DHCP_MAGIC_VENDOR, TAG_ANY);
882 if (vp && (strcmp(vp->vp_strvalue, "MSFT 98") == 0)) {
883 vp = pairfind(head, 262, DHCP_MAGIC_VENDOR, TAG_ANY);
886 * Reply should be broadcast.
888 if (vp) vp->vp_integer |= 0x8000;
889 packet->data[10] |= 0x80;
895 * FIXME: Nuke attributes that aren't used in the normal
896 * header for discover/requests.
901 * Client can request a LARGER size, but not a smaller
902 * one. They also cannot request a size larger than MTU.
904 maxms = pairfind(packet->vps, 57, DHCP_MAGIC_VENDOR, TAG_ANY);
905 mtu = pairfind(packet->vps, 26, DHCP_MAGIC_VENDOR, TAG_ANY);
907 if (mtu && (mtu->vp_integer < DEFAULT_PACKET_SIZE)) {
908 fr_strerror_printf("DHCP Fatal: Client says MTU is smaller than minimum permitted by the specification.");
912 if (maxms && (maxms->vp_integer < DEFAULT_PACKET_SIZE)) {
913 fr_strerror_printf("DHCP WARNING: Client says maximum message size is smaller than minimum permitted by the specification: fixing it");
914 maxms->vp_integer = DEFAULT_PACKET_SIZE;
917 if (maxms && mtu && (maxms->vp_integer > mtu->vp_integer)) {
918 fr_strerror_printf("DHCP WARNING: Client says MTU is smaller than maximum message size: fixing it");
919 maxms->vp_integer = mtu->vp_integer;
922 if (fr_debug_flag) fflush(stdout);
928 static int attr_cmp(void const *one, void const *two)
930 VALUE_PAIR const * const *a = one;
931 VALUE_PAIR const * const *b = two;
934 * DHCP-Message-Type is first, for simplicity.
936 if (((*a)->da->attr == 53) &&
937 (*b)->da->attr != 53) return -1;
940 * Relay-Agent is last
942 if (((*a)->da->attr == 82) &&
943 (*b)->da->attr != 82) return 1;
945 return ((*a)->da->attr - (*b)->da->attr);
951 static size_t fr_dhcp_vp2attr(VALUE_PAIR *vp, uint8_t *p, UNUSED size_t room)
957 * Search for all attributes of the same
958 * type, and pack them into the same
961 switch (vp->da->type) {
964 *p = vp->vp_integer & 0xff;
969 p[0] = (vp->vp_integer >> 8) & 0xff;
970 p[1] = vp->vp_integer & 0xff;
973 case PW_TYPE_INTEGER:
975 lvalue = htonl(vp->vp_integer);
976 memcpy(p, &lvalue, 4);
981 memcpy(p, &vp->vp_ipaddr, 4);
984 case PW_TYPE_ETHERNET:
986 memcpy(p, &vp->vp_ether, 6);
990 memcpy(p, vp->vp_strvalue, vp->length);
994 case PW_TYPE_TLV: /* FIXME: split it on 255? */
995 memcpy(p, vp->vp_tlv, vp->length);
1000 memcpy(p, vp->vp_octets, vp->length);
1001 length = vp->length;
1005 fr_strerror_printf("BAD TYPE2 %d", vp->da->type);
1013 static VALUE_PAIR *fr_dhcp_vp2suboption(RADIUS_PACKET *packet, VALUE_PAIR *vps)
1016 unsigned int attribute;
1019 VALUE_PAIR *vp, *tlv;
1021 attribute = vps->da->attr & 0xffff00ff;
1023 tlv = paircreate(packet, attribute, DHCP_MAGIC_VENDOR);
1024 if (!tlv) return NULL;
1027 for (vp = fr_cursor_init(&cursor, &vps);
1029 vp = fr_cursor_next(&cursor)) {
1031 * Group the attributes ONLY until we see a
1032 * non-TLV attribute.
1034 if (!vp->da->flags.is_tlv ||
1035 vp->da->flags.extended ||
1036 ((vp->da->attr & 0xffff00ff) != attribute)) {
1040 tlv->length += vp->length + 2;
1048 tlv->vp_tlv = talloc_array(tlv, uint8_t, tlv->length);
1055 for (vp = fr_cursor_init(&cursor, &vps);
1057 vp = fr_cursor_next(&cursor)) {
1058 if (!vp->da->flags.is_tlv ||
1059 vp->da->flags.extended ||
1060 ((vp->da->attr & 0xffff00ff) != attribute)) {
1064 length = fr_dhcp_vp2attr(vp, ptr + 2,
1065 tlv->vp_tlv + tlv->length - ptr);
1072 * Pack the attribute.
1074 ptr[0] = (vp->da->attr & 0xff00) >> 8;
1084 int fr_dhcp_encode(RADIUS_PACKET *packet)
1086 unsigned int i, num_vps;
1091 size_t dhcp_size, length;
1094 # ifdef WITH_UDPFROMTO
1095 char src_ip_buf[256];
1097 char dst_ip_buf[256];
1100 if (packet->data) return 0;
1102 packet->data_len = MAX_PACKET_SIZE;
1103 packet->data = talloc_zero_array(packet, uint8_t, packet->data_len);
1105 /* XXX Ugly ... should be set by the caller */
1106 if (packet->code == 0) packet->code = PW_DHCP_NAK;
1109 if ((packet->code >= PW_DHCP_DISCOVER) &&
1110 (packet->code <= PW_DHCP_INFORM)) {
1111 name = dhcp_message_types[packet->code - PW_DHCP_OFFSET];
1117 # ifdef WITH_UDPFROMTO
1118 "Encoding %s of id %08x from %s:%d to %s:%d\n",
1120 "Encoding %s of id %08x to %s:%d\n",
1122 name, (unsigned int) packet->id,
1123 # ifdef WITH_UDPFROMTO
1124 inet_ntop(packet->src_ipaddr.af,
1125 &packet->src_ipaddr.ipaddr,
1126 src_ip_buf, sizeof(src_ip_buf)),
1129 inet_ntop(packet->dst_ipaddr.af,
1130 &packet->dst_ipaddr.ipaddr,
1131 dst_ip_buf, sizeof(dst_ip_buf)),
1138 * @todo: Make this work again.
1141 mms = DEFAULT_PACKET_SIZE; /* maximum message size */
1144 * Clients can request a LARGER size, but not a
1145 * smaller one. They also cannot request a size
1149 /* DHCP-DHCP-Maximum-Msg-Size */
1150 vp = pairfind(packet->vps, 57, DHCP_MAGIC_VENDOR, TAG_ANY);
1151 if (vp && (vp->vp_integer > mms)) {
1152 mms = vp->vp_integer;
1154 if (mms > MAX_PACKET_SIZE) mms = MAX_PACKET_SIZE;
1158 vp = pairfind(packet->vps, 256, DHCP_MAGIC_VENDOR, TAG_ANY);
1160 *p++ = vp->vp_integer & 0xff;
1162 *p++ = 1; /* client message */
1165 /* DHCP-Hardware-Type */
1166 if ((vp = pairfind(packet->vps, 257, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1167 *p++ = vp->vp_integer & 0xFF;
1169 *p++ = 1; /* hardware type = ethernet */
1172 /* DHCP-Hardware-Address-Length */
1173 if ((vp = pairfind(packet->vps, 258, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1174 *p++ = vp->vp_integer & 0xFF;
1176 *p++ = 6; /* 6 bytes of ethernet */
1179 /* DHCP-Hop-Count */
1180 if ((vp = pairfind(packet->vps, 259, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1181 *p = vp->vp_integer & 0xff;
1185 /* DHCP-Transaction-Id */
1186 if ((vp = pairfind(packet->vps, 260, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1187 lvalue = htonl(vp->vp_integer);
1191 memcpy(p, &lvalue, 4);
1194 /* DHCP-Number-of-Seconds */
1195 if ((vp = pairfind(packet->vps, 261, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1196 lvalue = htonl(vp->vp_integer);
1197 memcpy(p, &lvalue, 2);
1202 if ((vp = pairfind(packet->vps, 262, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1203 lvalue = htons(vp->vp_integer);
1204 memcpy(p, &lvalue, 2);
1208 /* DHCP-Client-IP-Address */
1209 if ((vp = pairfind(packet->vps, 263, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1210 memcpy(p, &vp->vp_ipaddr, 4);
1214 /* DHCP-Your-IP-address */
1215 if ((vp = pairfind(packet->vps, 264, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1216 lvalue = vp->vp_ipaddr;
1218 lvalue = htonl(INADDR_ANY);
1220 memcpy(p, &lvalue, 4);
1223 /* DHCP-Server-IP-Address */
1224 vp = pairfind(packet->vps, 265, DHCP_MAGIC_VENDOR, TAG_ANY);
1226 /* DHCP-DHCP-Server-Identifier */
1227 if (!vp && (vp = pairfind(packet->vps, 54, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1228 lvalue = vp->vp_ipaddr;
1230 lvalue = htonl(INADDR_ANY);
1232 memcpy(p, &lvalue, 4);
1236 * DHCP-Gateway-IP-Address
1238 if ((vp = pairfind(packet->vps, 266, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1239 lvalue = vp->vp_ipaddr;
1241 lvalue = htonl(INADDR_ANY);
1243 memcpy(p, &lvalue, 4);
1246 /* DHCP-Client-Hardware-Address */
1247 if ((vp = pairfind(packet->vps, 267, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1248 if (vp->length == sizeof(vp->vp_ether)) {
1249 memcpy(p, vp->vp_ether, vp->length);
1250 } /* else ignore it */
1252 p += DHCP_CHADDR_LEN;
1254 /* DHCP-Server-Host-Name */
1255 if ((vp = pairfind(packet->vps, 268, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1256 if (vp->length > DHCP_SNAME_LEN) {
1257 memcpy(p, vp->vp_strvalue, DHCP_SNAME_LEN);
1259 memcpy(p, vp->vp_strvalue, vp->length);
1262 p += DHCP_SNAME_LEN;
1265 * Copy over DHCP-Boot-Filename.
1267 * FIXME: This copy should be delayed until AFTER the options
1268 * have been processed. If there are too many options for
1269 * the packet, then they go into the sname && filename fields.
1270 * When that happens, the boot filename is passed as an option,
1271 * instead of being placed verbatim in the filename field.
1274 /* DHCP-Boot-Filename */
1275 if ((vp = pairfind(packet->vps, 269, DHCP_MAGIC_VENDOR, TAG_ANY))) {
1276 if (vp->length > DHCP_FILE_LEN) {
1277 memcpy(p, vp->vp_strvalue, DHCP_FILE_LEN);
1279 memcpy(p, vp->vp_strvalue, vp->length);
1284 /* DHCP magic number */
1285 lvalue = htonl(DHCP_OPTION_MAGIC_NUMBER);
1286 memcpy(p, &lvalue, 4);
1292 if (fr_debug_flag > 1) {
1297 for (i = 0; i < 14; i++) {
1300 vp = pairmake(packet, NULL,
1301 dhcp_header_names[i], NULL, T_OP_EQ);
1304 strlcpy(buffer, fr_strerror(), sizeof(buffer));
1305 fr_strerror_printf("Cannot decode packet due to internal error: %s", buffer);
1309 switch (vp->da->type) {
1311 vp->vp_integer = p[0];
1316 vp->vp_integer = (p[0] << 8) | p[1];
1320 case PW_TYPE_INTEGER:
1321 memcpy(&vp->vp_integer, p, 4);
1322 vp->vp_integer = ntohl(vp->vp_integer);
1326 case PW_TYPE_IPADDR:
1327 memcpy(&vp->vp_ipaddr, p, 4);
1331 case PW_TYPE_STRING:
1332 vp->vp_strvalue = q = talloc_array(vp, char, dhcp_header_sizes[i] + 1);
1334 memcpy(q, p, dhcp_header_sizes[i]);
1335 q[dhcp_header_sizes[i]] = '\0';
1336 vp->length = strlen(vp->vp_strvalue);
1339 case PW_TYPE_OCTETS: /* only for Client HW Address */
1340 pairmemcpy(vp, p, packet->data[2]);
1343 case PW_TYPE_ETHERNET: /* only for Client HW Address */
1344 memcpy(vp->vp_ether, p, sizeof(vp->vp_ether));
1345 vp->length = sizeof(vp->vp_ether);
1349 fr_strerror_printf("Internal sanity check failed %d %d", vp->da->type, __LINE__);
1354 p += dhcp_header_sizes[i];
1361 * Jump over DHCP magic number, response, etc.
1367 * Before packing the attributes, re-order them so that
1368 * the array ones are all contiguous. This simplifies
1372 for (vp = fr_cursor_init(&cursor, &packet->vps);
1374 vp = fr_cursor_next(&cursor)) {
1380 array = talloc_array(packet, VALUE_PAIR*, num_vps);
1383 for (vp = fr_cursor_init(&cursor, &packet->vps);
1385 vp = fr_cursor_next(&cursor)) {
1390 * Sort the attributes.
1392 qsort(array, (size_t) num_vps, sizeof(VALUE_PAIR *), attr_cmp);
1395 fr_cursor_init(&cursor, &packet->vps);
1396 for (i = 0; i < num_vps; i++) {
1397 array[i]->next = NULL;
1398 fr_cursor_insert(&cursor, array[i]);
1403 p[0] = 0x35; /* DHCP-Message-Type */
1405 p[2] = packet->code - PW_DHCP_OFFSET;
1409 * Pack in the attributes.
1413 unsigned int num_entries = 1;
1417 if (vp->da->vendor != DHCP_MAGIC_VENDOR) goto next;
1418 if (vp->da->attr == 53) goto next; /* already done */
1419 if ((vp->da->attr > 255) &&
1420 (DHCP_BASE_ATTR(vp->da->attr) != PW_DHCP_OPTION_82)) goto next;
1423 if (vp->da->flags.extended) goto next;
1425 for (same = fr_cursor_init(&cursor, &vp->next);
1427 same = fr_cursor_next(&cursor)) {
1428 if (same->da->attr != vp->da->attr) break;
1433 * For client-identifier
1434 * @todo What's this meant to be doing?!
1437 if ((vp->da->type == PW_TYPE_ETHERNET) &&
1438 (vp->length == 6) &&
1439 (num_entries == 1)) {
1440 vp->da->type = PW_TYPE_OCTETS;
1441 memmove(vp->vp_octets + 1, vp->vp_octets, 6);
1442 vp->vp_octets[0] = 1;
1445 *(p++) = vp->da->attr & 0xff;
1447 *(p++) = 0; /* header isn't included in attr length */
1449 for (i = 0; i < num_entries; i++) {
1450 if (i != 0) debug_pair(vp);
1452 if (vp->da->flags.is_tlv) {
1456 * Should NOT have been encoded yet!
1458 tlv = fr_dhcp_vp2suboption(packet, vp);
1461 * Ignore it if there's an issue
1464 if (!tlv) goto next;
1466 tlv->next = vp->next;
1471 length = fr_dhcp_vp2attr(vp, p, 0);
1474 * This will never happen due to FreeRADIUS
1475 * limitations: sizeof(vp->vp_octets) < 255
1478 fr_strerror_printf("WARNING Ignoring too long attribute %s!", vp->da->name);
1483 * More than one attribute of the same type
1484 * in a row: they are packed together
1485 * into the same TLV. If we overflow,
1488 if ((*plength + length) > 255) {
1489 fr_strerror_printf("WARNING Ignoring too long attribute %s!", vp->da->name);
1496 if (vp->next && (vp->next->da->attr == vp->da->attr)) {
1499 } /* loop over num_entries */
1505 p[0] = 0xff; /* end of option option */
1508 dhcp_size = p - packet->data;
1511 * FIXME: if (dhcp_size > mms),
1512 * then we put the extra options into the "sname" and "file"
1513 * fields, AND set the "end option option" in the "options"
1514 * field. We also set the "overload option",
1515 * and put options into the "file" field, followed by
1516 * the "sname" field. Where each option is completely
1517 * enclosed in the "file" and/or "sname" field, AND
1518 * followed by the "end of option", and MUST be followed
1519 * by padding option.
1521 * Yuck. That sucks...
1523 packet->data_len = dhcp_size;
1525 if (packet->data_len < DEFAULT_PACKET_SIZE) {
1526 memset(packet->data + packet->data_len, 0,
1527 DEFAULT_PACKET_SIZE - packet->data_len);
1528 packet->data_len = DEFAULT_PACKET_SIZE;
1531 if ((fr_debug_flag > 2) && fr_log_fp) {
1532 fprintf(fr_log_fp, "DHCP Sending %zu bytes\n", packet->data_len);
1533 for (i = 0; i < packet->data_len; i++) {
1534 if ((i & 0x0f) == 0x00) fprintf(fr_log_fp, "%d: ", i);
1535 fprintf(fr_log_fp, "%02x ", packet->data[i]);
1536 if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
1538 fprintf(fr_log_fp, "\n");
1545 int fr_dhcp_add_arp_entry(int fd, char const *interface,
1546 VALUE_PAIR *macaddr, VALUE_PAIR *ip)
1548 struct sockaddr_in *sin;
1552 fr_strerror_printf("No interface specified. Cannot update ARP table");
1556 if (!fr_assert(macaddr) ||
1557 !fr_assert((macaddr->da->type == PW_TYPE_ETHERNET) || (macaddr->da->type == PW_TYPE_OCTETS))) {
1558 fr_strerror_printf("Wrong VP type (%s) for chaddr",
1559 fr_int2str(dict_attr_types, macaddr->da->type, "<invalid>"));
1563 if (macaddr->length > sizeof(req.arp_ha.sa_data)) {
1564 fr_strerror_printf("arp sa_data field too small (%zu octets) to contain chaddr (%zu octets)",
1565 sizeof(req.arp_ha.sa_data), macaddr->length);
1569 memset(&req, 0, sizeof(req));
1570 sin = (struct sockaddr_in *) &req.arp_pa;
1571 sin->sin_family = AF_INET;
1572 sin->sin_addr.s_addr = ip->vp_ipaddr;
1574 strlcpy(req.arp_dev, interface, sizeof(req.arp_dev));
1576 if (macaddr->da->type == PW_TYPE_ETHERNET) {
1577 memcpy(&req.arp_ha.sa_data, &macaddr->vp_ether, sizeof(macaddr->vp_ether));
1579 memcpy(&req.arp_ha.sa_data, macaddr->vp_octets, macaddr->length);
1582 req.arp_flags = ATF_COM;
1583 if (ioctl(fd, SIOCSARP, &req) < 0) {
1584 fr_strerror_printf("Failed to add entry in ARP cache: %s (%d)", fr_syserror(errno), errno);
1591 int fr_dhcp_add_arp_entry(UNUSED int fd, UNUSED char const *interface,
1592 UNUSED VALUE_PAIR *macaddr, UNUSED VALUE_PAIR *ip)
1594 fr_strerror_printf("Adding ARP entry is unsupported on this system");