2 * Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #include "krb5_locl.h"
39 struct PAC_INFO_BUFFER {
49 struct PAC_INFO_BUFFER buffers[1];
52 struct krb5_pac_data {
55 struct PAC_INFO_BUFFER *server_checksum;
56 struct PAC_INFO_BUFFER *privsvr_checksum;
57 struct PAC_INFO_BUFFER *logon_name;
60 #define PAC_ALIGNMENT 8
62 #define PACTYPE_SIZE 8
63 #define PAC_INFO_BUFFER_SIZE 16
65 #define PAC_SERVER_CHECKSUM 6
66 #define PAC_PRIVSVR_CHECKSUM 7
67 #define PAC_LOGON_NAME 10
68 #define PAC_CONSTRAINED_DELEGATION 11
70 #define CHECK(r,f,l) \
72 if (((r) = f ) != 0) { \
73 krb5_clear_error_string(context); \
78 static const char zeros[PAC_ALIGNMENT] = { 0 };
85 krb5_pac_parse(krb5_context context, const void *ptr, size_t len,
90 krb5_storage *sp = NULL;
91 uint32_t i, tmp, tmp2, header_end;
93 p = calloc(1, sizeof(*p));
96 krb5_set_error_message(context, ret, "malloc: out of memory");
100 sp = krb5_storage_from_readonly_mem(ptr, len);
103 krb5_set_error_message(context, ret, "malloc: out of memory");
106 krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);
108 CHECK(ret, krb5_ret_uint32(sp, &tmp), out);
109 CHECK(ret, krb5_ret_uint32(sp, &tmp2), out);
111 ret = EINVAL; /* Too few buffers */
112 krb5_set_error_message(context, ret, "PAC have too few buffer");
116 ret = EINVAL; /* Wrong version */
117 krb5_set_error_message(context, ret, "PAC have wrong version");
122 sizeof(*p->pac) + (sizeof(p->pac->buffers[0]) * (tmp - 1)));
123 if (p->pac == NULL) {
125 krb5_set_error_message(context, ret, "malloc: out of memory");
129 p->pac->numbuffers = tmp;
130 p->pac->version = tmp2;
132 header_end = PACTYPE_SIZE + (PAC_INFO_BUFFER_SIZE * p->pac->numbuffers);
133 if (header_end > len) {
138 for (i = 0; i < p->pac->numbuffers; i++) {
139 CHECK(ret, krb5_ret_uint32(sp, &p->pac->buffers[i].type), out);
140 CHECK(ret, krb5_ret_uint32(sp, &p->pac->buffers[i].buffersize), out);
141 CHECK(ret, krb5_ret_uint32(sp, &p->pac->buffers[i].offset_lo), out);
142 CHECK(ret, krb5_ret_uint32(sp, &p->pac->buffers[i].offset_hi), out);
144 /* consistency checks */
145 if (p->pac->buffers[i].offset_lo & (PAC_ALIGNMENT - 1)) {
147 krb5_set_error_message(context, ret, "PAC out of allignment");
150 if (p->pac->buffers[i].offset_hi) {
152 krb5_set_error_message(context, ret, "PAC high offset set");
155 if (p->pac->buffers[i].offset_lo > len) {
157 krb5_set_error_message(context, ret, "PAC offset off end");
160 if (p->pac->buffers[i].offset_lo < header_end) {
162 krb5_set_error_message(context, ret, "PAC offset inside header: %lu %lu",
163 (unsigned long)p->pac->buffers[i].offset_lo,
164 (unsigned long)header_end);
167 if (p->pac->buffers[i].buffersize > len - p->pac->buffers[i].offset_lo){
169 krb5_set_error_message(context, ret, "PAC length off end");
173 /* let save pointer to data we need later */
174 if (p->pac->buffers[i].type == PAC_SERVER_CHECKSUM) {
175 if (p->server_checksum) {
177 krb5_set_error_message(context, ret, "PAC have two server checksums");
180 p->server_checksum = &p->pac->buffers[i];
181 } else if (p->pac->buffers[i].type == PAC_PRIVSVR_CHECKSUM) {
182 if (p->privsvr_checksum) {
184 krb5_set_error_message(context, ret, "PAC have two KDC checksums");
187 p->privsvr_checksum = &p->pac->buffers[i];
188 } else if (p->pac->buffers[i].type == PAC_LOGON_NAME) {
191 krb5_set_error_message(context, ret, "PAC have two logon names");
194 p->logon_name = &p->pac->buffers[i];
198 ret = krb5_data_copy(&p->data, ptr, len);
202 krb5_storage_free(sp);
209 krb5_storage_free(sp);
221 krb5_pac_init(krb5_context context, krb5_pac *pac)
226 p = calloc(1, sizeof(*p));
228 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
232 p->pac = calloc(1, sizeof(*p->pac));
233 if (p->pac == NULL) {
235 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
239 ret = krb5_data_alloc(&p->data, PACTYPE_SIZE);
243 krb5_set_error_message(context, ret, "malloc: out of memory");
253 krb5_pac_add_buffer(krb5_context context, krb5_pac p,
254 uint32_t type, const krb5_data *data)
258 size_t len, offset, header_end, old_end;
261 len = p->pac->numbuffers;
263 ptr = realloc(p->pac,
264 sizeof(*p->pac) + (sizeof(p->pac->buffers[0]) * len));
266 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
271 for (i = 0; i < len; i++)
272 p->pac->buffers[i].offset_lo += PAC_INFO_BUFFER_SIZE;
274 offset = p->data.length + PAC_INFO_BUFFER_SIZE;
276 p->pac->buffers[len].type = type;
277 p->pac->buffers[len].buffersize = data->length;
278 p->pac->buffers[len].offset_lo = offset;
279 p->pac->buffers[len].offset_hi = 0;
281 old_end = p->data.length;
282 len = p->data.length + data->length + PAC_INFO_BUFFER_SIZE;
283 if (len < p->data.length) {
284 krb5_set_error_message(context, EINVAL, "integer overrun");
288 /* align to PAC_ALIGNMENT */
289 len = ((len + PAC_ALIGNMENT - 1) / PAC_ALIGNMENT) * PAC_ALIGNMENT;
291 ret = krb5_data_realloc(&p->data, len);
293 krb5_set_error_message(context, ret, "malloc: out of memory");
298 * make place for new PAC INFO BUFFER header
300 header_end = PACTYPE_SIZE + (PAC_INFO_BUFFER_SIZE * p->pac->numbuffers);
301 memmove((unsigned char *)p->data.data + header_end + PAC_INFO_BUFFER_SIZE,
302 (unsigned char *)p->data.data + header_end ,
303 old_end - header_end);
304 memset((unsigned char *)p->data.data + header_end, 0, PAC_INFO_BUFFER_SIZE);
307 * copy in new data part
310 memcpy((unsigned char *)p->data.data + offset,
311 data->data, data->length);
312 memset((unsigned char *)p->data.data + offset + data->length,
313 0, p->data.length - offset - data->length);
315 p->pac->numbuffers += 1;
321 krb5_pac_get_buffer(krb5_context context, krb5_pac p,
322 uint32_t type, krb5_data *data)
327 for (i = 0; i < p->pac->numbuffers; i++) {
328 size_t len = p->pac->buffers[i].buffersize;
329 size_t offset = p->pac->buffers[i].offset_lo;
331 if (p->pac->buffers[i].type != type)
334 ret = krb5_data_copy(data, (unsigned char *)p->data.data + offset, len);
336 krb5_set_error_message(context, ret, "malloc: out of memory");
341 krb5_set_error_message(context, ENOENT, "No PAC buffer of type %lu was found",
342 (unsigned long)type);
351 krb5_pac_get_types(krb5_context context,
358 *types = calloc(p->pac->numbuffers, sizeof(*types));
359 if (*types == NULL) {
361 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
364 for (i = 0; i < p->pac->numbuffers; i++)
365 (*types)[i] = p->pac->buffers[i].type;
366 *len = p->pac->numbuffers;
376 krb5_pac_free(krb5_context context, krb5_pac pac)
378 krb5_data_free(&pac->data);
387 static krb5_error_code
388 verify_checksum(krb5_context context,
389 const struct PAC_INFO_BUFFER *sig,
390 const krb5_data *data,
391 void *ptr, size_t len,
392 const krb5_keyblock *key)
394 krb5_crypto crypto = NULL;
395 krb5_storage *sp = NULL;
400 memset(&cksum, 0, sizeof(cksum));
402 sp = krb5_storage_from_mem((char *)data->data + sig->offset_lo,
405 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
408 krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);
410 CHECK(ret, krb5_ret_uint32(sp, &type), out);
411 cksum.cksumtype = type;
412 cksum.checksum.length =
413 sig->buffersize - krb5_storage_seek(sp, 0, SEEK_CUR);
414 cksum.checksum.data = malloc(cksum.checksum.length);
415 if (cksum.checksum.data == NULL) {
417 krb5_set_error_message(context, ret, "malloc: out of memory");
420 ret = krb5_storage_read(sp, cksum.checksum.data, cksum.checksum.length);
421 if (ret != cksum.checksum.length) {
423 krb5_set_error_message(context, ret, "PAC checksum missing checksum");
427 if (!krb5_checksum_is_keyed(context, cksum.cksumtype)) {
429 krb5_set_error_message(context, ret, "Checksum type %d not keyed",
434 ret = krb5_crypto_init(context, key, 0, &crypto);
438 ret = krb5_verify_checksum(context, crypto, KRB5_KU_OTHER_CKSUM,
440 free(cksum.checksum.data);
441 krb5_crypto_destroy(context, crypto);
442 krb5_storage_free(sp);
447 if (cksum.checksum.data)
448 free(cksum.checksum.data);
450 krb5_storage_free(sp);
452 krb5_crypto_destroy(context, crypto);
456 static krb5_error_code
457 create_checksum(krb5_context context,
458 const krb5_keyblock *key,
459 void *data, size_t datalen,
460 void *sig, size_t siglen)
462 krb5_crypto crypto = NULL;
466 ret = krb5_crypto_init(context, key, 0, &crypto);
470 ret = krb5_create_checksum(context, crypto, KRB5_KU_OTHER_CKSUM, 0,
471 data, datalen, &cksum);
472 krb5_crypto_destroy(context, crypto);
476 if (cksum.checksum.length != siglen) {
477 krb5_set_error_message(context, EINVAL, "pac checksum wrong length");
478 free_Checksum(&cksum);
482 memcpy(sig, cksum.checksum.data, siglen);
483 free_Checksum(&cksum);
493 #define NTTIME_EPOCH 0x019DB1DED53E8000LL
496 unix2nttime(time_t unix_time)
499 wt = unix_time * (uint64_t)10000000 + (uint64_t)NTTIME_EPOCH;
503 static krb5_error_code
504 verify_logonname(krb5_context context,
505 const struct PAC_INFO_BUFFER *logon_name,
506 const krb5_data *data,
508 krb5_const_principal principal)
512 uint32_t time1, time2;
517 sp = krb5_storage_from_readonly_mem((const char *)data->data + logon_name->offset_lo,
518 logon_name->buffersize);
520 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
524 krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);
526 CHECK(ret, krb5_ret_uint32(sp, &time1), out);
527 CHECK(ret, krb5_ret_uint32(sp, &time2), out);
531 t1 = unix2nttime(authtime);
532 t2 = ((uint64_t)time2 << 32) | time1;
534 krb5_storage_free(sp);
535 krb5_set_error_message(context, EINVAL, "PAC timestamp mismatch");
539 CHECK(ret, krb5_ret_uint16(sp, &len), out);
541 krb5_storage_free(sp);
542 krb5_set_error_message(context, EINVAL, "PAC logon name length missing");
548 krb5_storage_free(sp);
549 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
552 ret = krb5_storage_read(sp, s, len);
554 krb5_storage_free(sp);
555 krb5_set_error_message(context, EINVAL, "Failed to read PAC logon name");
558 krb5_storage_free(sp);
560 size_t ucs2len = len / 2;
563 unsigned int flags = WIND_RW_LE;
565 ucs2 = malloc(sizeof(ucs2[0]) * ucs2len);
567 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
570 ret = wind_ucs2read(s, len, &flags, ucs2, &ucs2len);
574 krb5_set_error_message(context, ret, "Failed to convert string to UCS-2");
577 ret = wind_ucs2utf8_length(ucs2, ucs2len, &u8len);
580 krb5_set_error_message(context, ret, "Failed to count length of UCS-2 string");
583 u8len += 1; /* Add space for NUL */
587 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
590 ret = wind_ucs2utf8(ucs2, ucs2len, s, &u8len);
593 krb5_set_error_message(context, ret, "Failed to convert to UTF-8");
597 ret = krb5_parse_name_flags(context, s, KRB5_PRINCIPAL_PARSE_NO_REALM, &p2);
602 if (krb5_principal_compare_any_realm(context, principal, p2) != TRUE) {
604 krb5_set_error_message(context, ret, "PAC logon name mismatch");
606 krb5_free_principal(context, p2);
616 static krb5_error_code
617 build_logon_name(krb5_context context,
619 krb5_const_principal principal,
628 t = unix2nttime(authtime);
630 krb5_data_zero(logon);
632 sp = krb5_storage_emem();
634 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
637 krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);
639 CHECK(ret, krb5_store_uint32(sp, t & 0xffffffff), out);
640 CHECK(ret, krb5_store_uint32(sp, t >> 32), out);
642 ret = krb5_unparse_name_flags(context, principal,
643 KRB5_PRINCIPAL_UNPARSE_NO_REALM, &s);
649 CHECK(ret, krb5_store_uint16(sp, len * 2), out);
651 #if 1 /* cheat for now */
652 s2 = malloc(len * 2);
658 for (i = 0; i < len; i++) {
664 /* write libwind code here */
667 ret = krb5_storage_write(sp, s2, len * 2);
669 if (ret != len * 2) {
673 ret = krb5_storage_to_data(sp, logon);
676 krb5_storage_free(sp);
680 krb5_storage_free(sp);
690 krb5_pac_verify(krb5_context context,
693 krb5_const_principal principal,
694 const krb5_keyblock *server,
695 const krb5_keyblock *privsvr)
699 if (pac->server_checksum == NULL) {
700 krb5_set_error_message(context, EINVAL, "PAC missing server checksum");
703 if (pac->privsvr_checksum == NULL) {
704 krb5_set_error_message(context, EINVAL, "PAC missing kdc checksum");
707 if (pac->logon_name == NULL) {
708 krb5_set_error_message(context, EINVAL, "PAC missing logon name");
712 ret = verify_logonname(context,
721 * in the service case, clean out data option of the privsvr and
722 * server checksum before checking the checksum.
727 ret = krb5_copy_data(context, &pac->data, ©);
731 if (pac->server_checksum->buffersize < 4)
733 if (pac->privsvr_checksum->buffersize < 4)
736 memset((char *)copy->data + pac->server_checksum->offset_lo + 4,
738 pac->server_checksum->buffersize - 4);
740 memset((char *)copy->data + pac->privsvr_checksum->offset_lo + 4,
742 pac->privsvr_checksum->buffersize - 4);
744 ret = verify_checksum(context,
745 pac->server_checksum,
750 krb5_free_data(context, copy);
755 ret = verify_checksum(context,
756 pac->privsvr_checksum,
758 (char *)pac->data.data
759 + pac->server_checksum->offset_lo + 4,
760 pac->server_checksum->buffersize - 4,
773 static krb5_error_code
774 fill_zeros(krb5_context context, krb5_storage *sp, size_t len)
781 if (l > sizeof(zeros))
783 sret = krb5_storage_write(sp, zeros, l);
785 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
793 static krb5_error_code
794 pac_checksum(krb5_context context,
795 const krb5_keyblock *key,
799 krb5_cksumtype cktype;
801 krb5_crypto crypto = NULL;
803 ret = krb5_crypto_init(context, key, 0, &crypto);
807 ret = krb5_crypto_get_checksum_type(context, crypto, &cktype);
808 krb5_crypto_destroy(context, crypto);
812 if (krb5_checksum_is_keyed(context, cktype) == FALSE) {
813 krb5_set_error_message(context, EINVAL, "PAC checksum type is not keyed");
817 ret = krb5_checksumsize(context, cktype, cksumsize);
821 *cksumtype = (uint32_t)cktype;
827 _krb5_pac_sign(krb5_context context,
830 krb5_principal principal,
831 const krb5_keyblock *server_key,
832 const krb5_keyblock *priv_key,
836 krb5_storage *sp = NULL, *spdata = NULL;
838 size_t server_size, priv_size;
839 uint32_t server_offset = 0, priv_offset = 0;
840 uint32_t server_cksumtype = 0, priv_cksumtype = 0;
844 krb5_data_zero(&logon);
846 if (p->logon_name == NULL)
848 if (p->server_checksum == NULL)
850 if (p->privsvr_checksum == NULL)
856 ptr = realloc(p->pac, sizeof(*p->pac) + (sizeof(p->pac->buffers[0]) * (p->pac->numbuffers + num - 1)));
858 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
863 if (p->logon_name == NULL) {
864 p->logon_name = &p->pac->buffers[p->pac->numbuffers++];
865 memset(p->logon_name, 0, sizeof(*p->logon_name));
866 p->logon_name->type = PAC_LOGON_NAME;
868 if (p->server_checksum == NULL) {
869 p->server_checksum = &p->pac->buffers[p->pac->numbuffers++];
870 memset(p->server_checksum, 0, sizeof(*p->server_checksum));
871 p->server_checksum->type = PAC_SERVER_CHECKSUM;
873 if (p->privsvr_checksum == NULL) {
874 p->privsvr_checksum = &p->pac->buffers[p->pac->numbuffers++];
875 memset(p->privsvr_checksum, 0, sizeof(*p->privsvr_checksum));
876 p->privsvr_checksum->type = PAC_PRIVSVR_CHECKSUM;
880 /* Calculate LOGON NAME */
881 ret = build_logon_name(context, authtime, principal, &logon);
885 /* Set lengths for checksum */
886 ret = pac_checksum(context, server_key, &server_cksumtype, &server_size);
889 ret = pac_checksum(context, priv_key, &priv_cksumtype, &priv_size);
894 sp = krb5_storage_emem();
896 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
899 krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);
901 spdata = krb5_storage_emem();
902 if (spdata == NULL) {
903 krb5_storage_free(sp);
904 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
907 krb5_storage_set_flags(spdata, KRB5_STORAGE_BYTEORDER_LE);
909 CHECK(ret, krb5_store_uint32(sp, p->pac->numbuffers), out);
910 CHECK(ret, krb5_store_uint32(sp, p->pac->version), out);
912 end = PACTYPE_SIZE + (PAC_INFO_BUFFER_SIZE * p->pac->numbuffers);
914 for (i = 0; i < p->pac->numbuffers; i++) {
921 if (p->pac->buffers[i].type == PAC_SERVER_CHECKSUM) {
922 len = server_size + 4;
923 server_offset = end + 4;
924 CHECK(ret, krb5_store_uint32(spdata, server_cksumtype), out);
925 CHECK(ret, fill_zeros(context, spdata, server_size), out);
926 } else if (p->pac->buffers[i].type == PAC_PRIVSVR_CHECKSUM) {
928 priv_offset = end + 4;
929 CHECK(ret, krb5_store_uint32(spdata, priv_cksumtype), out);
930 CHECK(ret, fill_zeros(context, spdata, priv_size), out);
931 } else if (p->pac->buffers[i].type == PAC_LOGON_NAME) {
932 len = krb5_storage_write(spdata, logon.data, logon.length);
933 if (logon.length != len) {
938 len = p->pac->buffers[i].buffersize;
939 ptr = (char *)p->data.data + p->pac->buffers[i].offset_lo;
941 sret = krb5_storage_write(spdata, ptr, len);
944 krb5_set_error_message(context, ret, "malloc: out of memory");
947 /* XXX if not aligned, fill_zeros */
951 CHECK(ret, krb5_store_uint32(sp, p->pac->buffers[i].type), out);
952 CHECK(ret, krb5_store_uint32(sp, len), out);
953 CHECK(ret, krb5_store_uint32(sp, end), out);
954 CHECK(ret, krb5_store_uint32(sp, 0), out);
956 /* advance data endpointer and align */
961 e = ((end + PAC_ALIGNMENT - 1) / PAC_ALIGNMENT) * PAC_ALIGNMENT;
963 CHECK(ret, fill_zeros(context, spdata, e - end), out);
970 /* assert (server_offset != 0 && priv_offset != 0); */
973 ret = krb5_storage_to_data(spdata, &d);
975 krb5_set_error_message(context, ret, "malloc: out of memory");
978 ret = krb5_storage_write(sp, d.data, d.length);
979 if (ret != d.length) {
982 krb5_set_error_message(context, ret, "malloc: out of memory");
987 ret = krb5_storage_to_data(sp, &d);
989 krb5_set_error_message(context, ret, "malloc: out of memory");
995 ret = create_checksum(context, server_key,
997 (char *)d.data + server_offset, server_size);
1003 ret = create_checksum(context, priv_key,
1004 (char *)d.data + server_offset, server_size,
1005 (char *)d.data + priv_offset, priv_size);
1014 krb5_data_free(&logon);
1015 krb5_storage_free(sp);
1016 krb5_storage_free(spdata);
1020 krb5_data_free(&logon);
1022 krb5_storage_free(sp);
1024 krb5_storage_free(spdata);