/contrib/bind9/lib/dns/spnego.c

https://bitbucket.org/freebsd/freebsd-head/ · C · 1800 lines · 1383 code · 212 blank · 205 comment · 256 complexity · 66ace5ca8ee56058029efbe2aa15a53b MD5 · raw file

  1. /*
  2. * Copyright (C) 2006-2012 Internet Systems Consortium, Inc. ("ISC")
  3. *
  4. * Permission to use, copy, modify, and/or distribute this software for any
  5. * purpose with or without fee is hereby granted, provided that the above
  6. * copyright notice and this permission notice appear in all copies.
  7. *
  8. * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  9. * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  10. * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  11. * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  12. * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  13. * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  14. * PERFORMANCE OF THIS SOFTWARE.
  15. */
  16. /* $Id$ */
  17. /*! \file
  18. * \brief
  19. * Portable SPNEGO implementation.
  20. *
  21. * This is part of a portable implementation of the SPNEGO protocol
  22. * (RFCs 2478 and 4178). This implementation uses the RFC 4178 ASN.1
  23. * module but is not a full implementation of the RFC 4178 protocol;
  24. * at the moment, we only support GSS-TSIG with Kerberos
  25. * authentication, so we only need enough of the SPNEGO protocol to
  26. * support that.
  27. *
  28. * The files that make up this portable SPNEGO implementation are:
  29. * \li spnego.c (this file)
  30. * \li spnego.h (API SPNEGO exports to the rest of lib/dns)
  31. * \li spnego.asn1 (SPNEGO ASN.1 module)
  32. * \li spnego_asn1.c (routines generated from spngo.asn1)
  33. * \li spnego_asn1.pl (perl script to generate spnego_asn1.c)
  34. *
  35. * Everything but the functions exported in spnego.h is static, to
  36. * avoid possible conflicts with other libraries (particularly Heimdal,
  37. * since much of this code comes from Heimdal by way of mod_auth_kerb).
  38. *
  39. * spnego_asn1.c is shipped as part of lib/dns because generating it
  40. * requires both Perl and the Heimdal ASN.1 compiler. See
  41. * spnego_asn1.pl for further details. We've tried to eliminate all
  42. * compiler warnings from the generated code, but you may see a few
  43. * when using a compiler version we haven't tested yet.
  44. */
  45. /*
  46. * Portions of this code were derived from mod_auth_kerb and Heimdal.
  47. * These packages are available from:
  48. *
  49. * http://modauthkerb.sourceforge.net/
  50. * http://www.pdc.kth.se/heimdal/
  51. *
  52. * and were released under the following licenses:
  53. *
  54. * ----------------------------------------------------------------
  55. *
  56. * Copyright (c) 2004 Masarykova universita
  57. * (Masaryk University, Brno, Czech Republic)
  58. * All rights reserved.
  59. *
  60. * Redistribution and use in source and binary forms, with or without
  61. * modification, are permitted provided that the following conditions are met:
  62. *
  63. * 1. Redistributions of source code must retain the above copyright notice,
  64. * this list of conditions and the following disclaimer.
  65. *
  66. * 2. Redistributions in binary form must reproduce the above copyright
  67. * notice, this list of conditions and the following disclaimer in the
  68. * documentation and/or other materials provided with the distribution.
  69. *
  70. * 3. Neither the name of the University nor the names of its contributors may
  71. * be used to endorse or promote products derived from this software
  72. * without specific prior written permission.
  73. *
  74. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  75. * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  76. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  77. * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  78. * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  79. * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  80. * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  81. * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  82. * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  83. * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  84. * POSSIBILITY OF SUCH DAMAGE.
  85. *
  86. * ----------------------------------------------------------------
  87. *
  88. * Copyright (c) 1997 - 2003 Kungliga Tekniska Högskolan
  89. * (Royal Institute of Technology, Stockholm, Sweden).
  90. * All rights reserved.
  91. *
  92. * Redistribution and use in source and binary forms, with or without
  93. * modification, are permitted provided that the following conditions
  94. * are met:
  95. *
  96. * 1. Redistributions of source code must retain the above copyright
  97. * notice, this list of conditions and the following disclaimer.
  98. *
  99. * 2. Redistributions in binary form must reproduce the above copyright
  100. * notice, this list of conditions and the following disclaimer in the
  101. * documentation and/or other materials provided with the distribution.
  102. *
  103. * 3. Neither the name of the Institute nor the names of its contributors
  104. * may be used to endorse or promote products derived from this software
  105. * without specific prior written permission.
  106. *
  107. * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  108. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  109. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  110. * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  111. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  112. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  113. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  114. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  115. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  116. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  117. * SUCH DAMAGE.
  118. */
  119. /*
  120. * XXXSRA We should omit this file entirely in Makefile.in via autoconf,
  121. * but this will keep it from generating errors until that's written.
  122. */
  123. #ifdef GSSAPI
  124. /*
  125. * XXXSRA Some of the following files are almost certainly unnecessary,
  126. * but using this list (borrowed from gssapictx.c) gets rid of some
  127. * whacky compilation errors when building with MSVC and should be
  128. * harmless in any case.
  129. */
  130. #include <config.h>
  131. #include <stdlib.h>
  132. #include <errno.h>
  133. #include <isc/buffer.h>
  134. #include <isc/dir.h>
  135. #include <isc/entropy.h>
  136. #include <isc/lex.h>
  137. #include <isc/mem.h>
  138. #include <isc/once.h>
  139. #include <isc/random.h>
  140. #include <isc/string.h>
  141. #include <isc/time.h>
  142. #include <isc/util.h>
  143. #include <dns/fixedname.h>
  144. #include <dns/name.h>
  145. #include <dns/rdata.h>
  146. #include <dns/rdataclass.h>
  147. #include <dns/result.h>
  148. #include <dns/types.h>
  149. #include <dns/keyvalues.h>
  150. #include <dns/log.h>
  151. #include <dst/gssapi.h>
  152. #include <dst/result.h>
  153. #include "dst_internal.h"
  154. /*
  155. * The API we export
  156. */
  157. #include "spnego.h"
  158. /* asn1_err.h */
  159. /* Generated from ../../../lib/asn1/asn1_err.et */
  160. #ifndef ERROR_TABLE_BASE_asn1
  161. /* these may be brought in already via gssapi_krb5.h */
  162. typedef enum asn1_error_number {
  163. ASN1_BAD_TIMEFORMAT = 1859794432,
  164. ASN1_MISSING_FIELD = 1859794433,
  165. ASN1_MISPLACED_FIELD = 1859794434,
  166. ASN1_TYPE_MISMATCH = 1859794435,
  167. ASN1_OVERFLOW = 1859794436,
  168. ASN1_OVERRUN = 1859794437,
  169. ASN1_BAD_ID = 1859794438,
  170. ASN1_BAD_LENGTH = 1859794439,
  171. ASN1_BAD_FORMAT = 1859794440,
  172. ASN1_PARSE_ERROR = 1859794441
  173. } asn1_error_number;
  174. #define ERROR_TABLE_BASE_asn1 1859794432
  175. #endif
  176. #define __asn1_common_definitions__
  177. typedef struct octet_string {
  178. size_t length;
  179. void *data;
  180. } octet_string;
  181. typedef char *general_string;
  182. typedef char *utf8_string;
  183. typedef struct oid {
  184. size_t length;
  185. unsigned *components;
  186. } oid;
  187. /* der.h */
  188. typedef enum {
  189. ASN1_C_UNIV = 0, ASN1_C_APPL = 1,
  190. ASN1_C_CONTEXT = 2, ASN1_C_PRIVATE = 3
  191. } Der_class;
  192. typedef enum {
  193. PRIM = 0, CONS = 1
  194. } Der_type;
  195. /* Universal tags */
  196. enum {
  197. UT_Boolean = 1,
  198. UT_Integer = 2,
  199. UT_BitString = 3,
  200. UT_OctetString = 4,
  201. UT_Null = 5,
  202. UT_OID = 6,
  203. UT_Enumerated = 10,
  204. UT_Sequence = 16,
  205. UT_Set = 17,
  206. UT_PrintableString = 19,
  207. UT_IA5String = 22,
  208. UT_UTCTime = 23,
  209. UT_GeneralizedTime = 24,
  210. UT_VisibleString = 26,
  211. UT_GeneralString = 27
  212. };
  213. #define ASN1_INDEFINITE 0xdce0deed
  214. static int
  215. der_get_length(const unsigned char *p, size_t len,
  216. size_t * val, size_t * size);
  217. static int
  218. der_get_octet_string(const unsigned char *p, size_t len,
  219. octet_string * data, size_t * size);
  220. static int
  221. der_get_oid(const unsigned char *p, size_t len,
  222. oid * data, size_t * size);
  223. static int
  224. der_get_tag(const unsigned char *p, size_t len,
  225. Der_class * class, Der_type * type,
  226. int *tag, size_t * size);
  227. static int
  228. der_match_tag(const unsigned char *p, size_t len,
  229. Der_class class, Der_type type,
  230. int tag, size_t * size);
  231. static int
  232. der_match_tag_and_length(const unsigned char *p, size_t len,
  233. Der_class class, Der_type type, int tag,
  234. size_t * length_ret, size_t * size);
  235. static int
  236. decode_oid(const unsigned char *p, size_t len,
  237. oid * k, size_t * size);
  238. static int
  239. decode_enumerated(const unsigned char *p, size_t len, void *num, size_t *size);
  240. static int
  241. decode_octet_string(const unsigned char *, size_t, octet_string *, size_t *);
  242. static int
  243. der_put_int(unsigned char *p, size_t len, int val, size_t *);
  244. static int
  245. der_put_length(unsigned char *p, size_t len, size_t val, size_t *);
  246. static int
  247. der_put_octet_string(unsigned char *p, size_t len,
  248. const octet_string * data, size_t *);
  249. static int
  250. der_put_oid(unsigned char *p, size_t len,
  251. const oid * data, size_t * size);
  252. static int
  253. der_put_tag(unsigned char *p, size_t len, Der_class class, Der_type type,
  254. int tag, size_t *);
  255. static int
  256. der_put_length_and_tag(unsigned char *, size_t, size_t,
  257. Der_class, Der_type, int, size_t *);
  258. static int
  259. encode_enumerated(unsigned char *p, size_t len, const void *data, size_t *);
  260. static int
  261. encode_octet_string(unsigned char *p, size_t len,
  262. const octet_string * k, size_t *);
  263. static int
  264. encode_oid(unsigned char *p, size_t len,
  265. const oid * k, size_t *);
  266. static void
  267. free_octet_string(octet_string * k);
  268. static void
  269. free_oid (oid * k);
  270. static size_t
  271. length_len(size_t len);
  272. static int
  273. fix_dce(size_t reallen, size_t * len);
  274. /*
  275. * Include stuff generated by the ASN.1 compiler.
  276. */
  277. #include "spnego_asn1.c"
  278. static unsigned char gss_krb5_mech_oid_bytes[] = {
  279. 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x01, 0x02, 0x02
  280. };
  281. static gss_OID_desc gss_krb5_mech_oid_desc = {
  282. sizeof(gss_krb5_mech_oid_bytes),
  283. gss_krb5_mech_oid_bytes
  284. };
  285. static gss_OID GSS_KRB5_MECH = &gss_krb5_mech_oid_desc;
  286. static unsigned char gss_mskrb5_mech_oid_bytes[] = {
  287. 0x2a, 0x86, 0x48, 0x82, 0xf7, 0x12, 0x01, 0x02, 0x02
  288. };
  289. static gss_OID_desc gss_mskrb5_mech_oid_desc = {
  290. sizeof(gss_mskrb5_mech_oid_bytes),
  291. gss_mskrb5_mech_oid_bytes
  292. };
  293. static gss_OID GSS_MSKRB5_MECH = &gss_mskrb5_mech_oid_desc;
  294. static unsigned char gss_spnego_mech_oid_bytes[] = {
  295. 0x2b, 0x06, 0x01, 0x05, 0x05, 0x02
  296. };
  297. static gss_OID_desc gss_spnego_mech_oid_desc = {
  298. sizeof(gss_spnego_mech_oid_bytes),
  299. gss_spnego_mech_oid_bytes
  300. };
  301. static gss_OID GSS_SPNEGO_MECH = &gss_spnego_mech_oid_desc;
  302. /* spnegokrb5_locl.h */
  303. static OM_uint32
  304. gssapi_spnego_encapsulate(OM_uint32 *,
  305. unsigned char *,
  306. size_t,
  307. gss_buffer_t,
  308. const gss_OID);
  309. static OM_uint32
  310. gssapi_spnego_decapsulate(OM_uint32 *,
  311. gss_buffer_t,
  312. unsigned char **,
  313. size_t *,
  314. const gss_OID);
  315. /* mod_auth_kerb.c */
  316. static int
  317. cmp_gss_type(gss_buffer_t token, gss_OID oid)
  318. {
  319. unsigned char *p;
  320. size_t len;
  321. if (token->length == 0U)
  322. return (GSS_S_DEFECTIVE_TOKEN);
  323. p = token->value;
  324. if (*p++ != 0x60)
  325. return (GSS_S_DEFECTIVE_TOKEN);
  326. len = *p++;
  327. if (len & 0x80) {
  328. if ((len & 0x7f) > 4U)
  329. return (GSS_S_DEFECTIVE_TOKEN);
  330. p += len & 0x7f;
  331. }
  332. if (*p++ != 0x06)
  333. return (GSS_S_DEFECTIVE_TOKEN);
  334. if (((OM_uint32) *p++) != oid->length)
  335. return (GSS_S_DEFECTIVE_TOKEN);
  336. return (memcmp(p, oid->elements, oid->length));
  337. }
  338. /* accept_sec_context.c */
  339. /*
  340. * SPNEGO wrapper for Kerberos5 GSS-API kouril@ics.muni.cz, 2003 (mostly
  341. * based on Heimdal code)
  342. */
  343. static OM_uint32
  344. code_NegTokenArg(OM_uint32 * minor_status,
  345. const NegTokenResp * resp,
  346. unsigned char **outbuf,
  347. size_t * outbuf_size)
  348. {
  349. OM_uint32 ret;
  350. u_char *buf;
  351. size_t buf_size, buf_len = 0;
  352. buf_size = 1024;
  353. buf = malloc(buf_size);
  354. if (buf == NULL) {
  355. *minor_status = ENOMEM;
  356. return (GSS_S_FAILURE);
  357. }
  358. do {
  359. ret = encode_NegTokenResp(buf + buf_size - 1,
  360. buf_size,
  361. resp, &buf_len);
  362. if (ret == 0) {
  363. size_t tmp;
  364. ret = der_put_length_and_tag(buf + buf_size - buf_len - 1,
  365. buf_size - buf_len,
  366. buf_len,
  367. ASN1_C_CONTEXT,
  368. CONS,
  369. 1,
  370. &tmp);
  371. if (ret == 0)
  372. buf_len += tmp;
  373. }
  374. if (ret) {
  375. if (ret == ASN1_OVERFLOW) {
  376. u_char *tmp;
  377. buf_size *= 2;
  378. tmp = realloc(buf, buf_size);
  379. if (tmp == NULL) {
  380. *minor_status = ENOMEM;
  381. free(buf);
  382. return (GSS_S_FAILURE);
  383. }
  384. buf = tmp;
  385. } else {
  386. *minor_status = ret;
  387. free(buf);
  388. return (GSS_S_FAILURE);
  389. }
  390. }
  391. } while (ret == ASN1_OVERFLOW);
  392. *outbuf = malloc(buf_len);
  393. if (*outbuf == NULL) {
  394. *minor_status = ENOMEM;
  395. free(buf);
  396. return (GSS_S_FAILURE);
  397. }
  398. memcpy(*outbuf, buf + buf_size - buf_len, buf_len);
  399. *outbuf_size = buf_len;
  400. free(buf);
  401. return (GSS_S_COMPLETE);
  402. }
  403. static OM_uint32
  404. send_reject(OM_uint32 * minor_status,
  405. gss_buffer_t output_token)
  406. {
  407. NegTokenResp resp;
  408. OM_uint32 ret;
  409. resp.negState = malloc(sizeof(*resp.negState));
  410. if (resp.negState == NULL) {
  411. *minor_status = ENOMEM;
  412. return (GSS_S_FAILURE);
  413. }
  414. *(resp.negState) = reject;
  415. resp.supportedMech = NULL;
  416. resp.responseToken = NULL;
  417. resp.mechListMIC = NULL;
  418. ret = code_NegTokenArg(minor_status, &resp,
  419. (unsigned char **)&output_token->value,
  420. &output_token->length);
  421. free_NegTokenResp(&resp);
  422. if (ret)
  423. return (ret);
  424. return (GSS_S_BAD_MECH);
  425. }
  426. static OM_uint32
  427. send_accept(OM_uint32 * minor_status,
  428. gss_buffer_t output_token,
  429. gss_buffer_t mech_token,
  430. const gss_OID pref)
  431. {
  432. NegTokenResp resp;
  433. OM_uint32 ret;
  434. memset(&resp, 0, sizeof(resp));
  435. resp.negState = malloc(sizeof(*resp.negState));
  436. if (resp.negState == NULL) {
  437. *minor_status = ENOMEM;
  438. return (GSS_S_FAILURE);
  439. }
  440. *(resp.negState) = accept_completed;
  441. resp.supportedMech = malloc(sizeof(*resp.supportedMech));
  442. if (resp.supportedMech == NULL) {
  443. free_NegTokenResp(&resp);
  444. *minor_status = ENOMEM;
  445. return (GSS_S_FAILURE);
  446. }
  447. ret = der_get_oid(pref->elements,
  448. pref->length,
  449. resp.supportedMech,
  450. NULL);
  451. if (ret) {
  452. free_NegTokenResp(&resp);
  453. *minor_status = ENOMEM;
  454. return (GSS_S_FAILURE);
  455. }
  456. if (mech_token != NULL && mech_token->length != 0U) {
  457. resp.responseToken = malloc(sizeof(*resp.responseToken));
  458. if (resp.responseToken == NULL) {
  459. free_NegTokenResp(&resp);
  460. *minor_status = ENOMEM;
  461. return (GSS_S_FAILURE);
  462. }
  463. resp.responseToken->length = mech_token->length;
  464. resp.responseToken->data = mech_token->value;
  465. }
  466. ret = code_NegTokenArg(minor_status, &resp,
  467. (unsigned char **)&output_token->value,
  468. &output_token->length);
  469. if (resp.responseToken != NULL) {
  470. free(resp.responseToken);
  471. resp.responseToken = NULL;
  472. }
  473. free_NegTokenResp(&resp);
  474. if (ret)
  475. return (ret);
  476. return (GSS_S_COMPLETE);
  477. }
  478. OM_uint32
  479. gss_accept_sec_context_spnego(OM_uint32 *minor_status,
  480. gss_ctx_id_t *context_handle,
  481. const gss_cred_id_t acceptor_cred_handle,
  482. const gss_buffer_t input_token_buffer,
  483. const gss_channel_bindings_t input_chan_bindings,
  484. gss_name_t *src_name,
  485. gss_OID *mech_type,
  486. gss_buffer_t output_token,
  487. OM_uint32 *ret_flags,
  488. OM_uint32 *time_rec,
  489. gss_cred_id_t *delegated_cred_handle)
  490. {
  491. NegTokenInit init_token;
  492. OM_uint32 major_status;
  493. OM_uint32 minor_status2;
  494. gss_buffer_desc ibuf, obuf;
  495. gss_buffer_t ot = NULL;
  496. gss_OID pref = GSS_KRB5_MECH;
  497. unsigned char *buf;
  498. size_t buf_size;
  499. size_t len, taglen, ni_len;
  500. int found = 0;
  501. int ret;
  502. unsigned i;
  503. /*
  504. * Before doing anything else, see whether this is a SPNEGO
  505. * PDU. If not, dispatch to the GSSAPI library and get out.
  506. */
  507. if (cmp_gss_type(input_token_buffer, GSS_SPNEGO_MECH))
  508. return (gss_accept_sec_context(minor_status,
  509. context_handle,
  510. acceptor_cred_handle,
  511. input_token_buffer,
  512. input_chan_bindings,
  513. src_name,
  514. mech_type,
  515. output_token,
  516. ret_flags,
  517. time_rec,
  518. delegated_cred_handle));
  519. /*
  520. * If we get here, it's SPNEGO.
  521. */
  522. memset(&init_token, 0, sizeof(init_token));
  523. ret = gssapi_spnego_decapsulate(minor_status, input_token_buffer,
  524. &buf, &buf_size, GSS_SPNEGO_MECH);
  525. if (ret)
  526. return (ret);
  527. ret = der_match_tag_and_length(buf, buf_size, ASN1_C_CONTEXT, CONS,
  528. 0, &len, &taglen);
  529. if (ret)
  530. return (ret);
  531. ret = decode_NegTokenInit(buf + taglen, len, &init_token, &ni_len);
  532. if (ret) {
  533. *minor_status = EINVAL; /* XXX */
  534. return (GSS_S_DEFECTIVE_TOKEN);
  535. }
  536. for (i = 0; !found && i < init_token.mechTypes.len; ++i) {
  537. unsigned char mechbuf[17];
  538. size_t mech_len;
  539. ret = der_put_oid(mechbuf + sizeof(mechbuf) - 1,
  540. sizeof(mechbuf),
  541. &init_token.mechTypes.val[i],
  542. &mech_len);
  543. if (ret)
  544. return (GSS_S_DEFECTIVE_TOKEN);
  545. if (mech_len == GSS_KRB5_MECH->length &&
  546. memcmp(GSS_KRB5_MECH->elements,
  547. mechbuf + sizeof(mechbuf) - mech_len,
  548. mech_len) == 0) {
  549. found = 1;
  550. break;
  551. }
  552. if (mech_len == GSS_MSKRB5_MECH->length &&
  553. memcmp(GSS_MSKRB5_MECH->elements,
  554. mechbuf + sizeof(mechbuf) - mech_len,
  555. mech_len) == 0) {
  556. found = 1;
  557. if (i == 0)
  558. pref = GSS_MSKRB5_MECH;
  559. break;
  560. }
  561. }
  562. if (!found)
  563. return (send_reject(minor_status, output_token));
  564. if (i == 0 && init_token.mechToken != NULL) {
  565. ibuf.length = init_token.mechToken->length;
  566. ibuf.value = init_token.mechToken->data;
  567. major_status = gss_accept_sec_context(minor_status,
  568. context_handle,
  569. acceptor_cred_handle,
  570. &ibuf,
  571. input_chan_bindings,
  572. src_name,
  573. mech_type,
  574. &obuf,
  575. ret_flags,
  576. time_rec,
  577. delegated_cred_handle);
  578. if (GSS_ERROR(major_status)) {
  579. send_reject(&minor_status2, output_token);
  580. return (major_status);
  581. }
  582. ot = &obuf;
  583. }
  584. ret = send_accept(&minor_status2, output_token, ot, pref);
  585. if (ot != NULL && ot->length != 0U)
  586. gss_release_buffer(&minor_status2, ot);
  587. return (ret);
  588. }
  589. /* decapsulate.c */
  590. static OM_uint32
  591. gssapi_verify_mech_header(u_char ** str,
  592. size_t total_len,
  593. const gss_OID mech)
  594. {
  595. size_t len, len_len, mech_len, foo;
  596. int e;
  597. u_char *p = *str;
  598. if (total_len < 1U)
  599. return (GSS_S_DEFECTIVE_TOKEN);
  600. if (*p++ != 0x60)
  601. return (GSS_S_DEFECTIVE_TOKEN);
  602. e = der_get_length(p, total_len - 1, &len, &len_len);
  603. if (e || 1 + len_len + len != total_len)
  604. return (GSS_S_DEFECTIVE_TOKEN);
  605. p += len_len;
  606. if (*p++ != 0x06)
  607. return (GSS_S_DEFECTIVE_TOKEN);
  608. e = der_get_length(p, total_len - 1 - len_len - 1,
  609. &mech_len, &foo);
  610. if (e)
  611. return (GSS_S_DEFECTIVE_TOKEN);
  612. p += foo;
  613. if (mech_len != mech->length)
  614. return (GSS_S_BAD_MECH);
  615. if (memcmp(p, mech->elements, mech->length) != 0)
  616. return (GSS_S_BAD_MECH);
  617. p += mech_len;
  618. *str = p;
  619. return (GSS_S_COMPLETE);
  620. }
  621. /*
  622. * Remove the GSS-API wrapping from `in_token' giving `buf and buf_size' Does
  623. * not copy data, so just free `in_token'.
  624. */
  625. static OM_uint32
  626. gssapi_spnego_decapsulate(OM_uint32 *minor_status,
  627. gss_buffer_t input_token_buffer,
  628. unsigned char **buf,
  629. size_t *buf_len,
  630. const gss_OID mech)
  631. {
  632. u_char *p;
  633. OM_uint32 ret;
  634. p = input_token_buffer->value;
  635. ret = gssapi_verify_mech_header(&p,
  636. input_token_buffer->length,
  637. mech);
  638. if (ret) {
  639. *minor_status = ret;
  640. return (GSS_S_FAILURE);
  641. }
  642. *buf_len = input_token_buffer->length -
  643. (p - (u_char *) input_token_buffer->value);
  644. *buf = p;
  645. return (GSS_S_COMPLETE);
  646. }
  647. /* der_free.c */
  648. static void
  649. free_octet_string(octet_string *k)
  650. {
  651. free(k->data);
  652. k->data = NULL;
  653. }
  654. static void
  655. free_oid(oid *k)
  656. {
  657. free(k->components);
  658. k->components = NULL;
  659. }
  660. /* der_get.c */
  661. /*
  662. * All decoding functions take a pointer `p' to first position in which to
  663. * read, from the left, `len' which means the maximum number of characters we
  664. * are able to read, `ret' were the value will be returned and `size' where
  665. * the number of used bytes is stored. Either 0 or an error code is returned.
  666. */
  667. static int
  668. der_get_unsigned(const unsigned char *p, size_t len,
  669. unsigned *ret, size_t *size)
  670. {
  671. unsigned val = 0;
  672. size_t oldlen = len;
  673. while (len--)
  674. val = val * 256 + *p++;
  675. *ret = val;
  676. if (size)
  677. *size = oldlen;
  678. return (0);
  679. }
  680. static int
  681. der_get_int(const unsigned char *p, size_t len,
  682. int *ret, size_t *size)
  683. {
  684. int val = 0;
  685. size_t oldlen = len;
  686. if (len > 0U) {
  687. val = (signed char)*p++;
  688. while (--len)
  689. val = val * 256 + *p++;
  690. }
  691. *ret = val;
  692. if (size)
  693. *size = oldlen;
  694. return (0);
  695. }
  696. static int
  697. der_get_length(const unsigned char *p, size_t len,
  698. size_t *val, size_t *size)
  699. {
  700. size_t v;
  701. if (len <= 0U)
  702. return (ASN1_OVERRUN);
  703. --len;
  704. v = *p++;
  705. if (v < 128U) {
  706. *val = v;
  707. if (size)
  708. *size = 1;
  709. } else {
  710. int e;
  711. size_t l;
  712. unsigned tmp;
  713. if (v == 0x80U) {
  714. *val = ASN1_INDEFINITE;
  715. if (size)
  716. *size = 1;
  717. return (0);
  718. }
  719. v &= 0x7F;
  720. if (len < v)
  721. return (ASN1_OVERRUN);
  722. e = der_get_unsigned(p, v, &tmp, &l);
  723. if (e)
  724. return (e);
  725. *val = tmp;
  726. if (size)
  727. *size = l + 1;
  728. }
  729. return (0);
  730. }
  731. static int
  732. der_get_octet_string(const unsigned char *p, size_t len,
  733. octet_string *data, size_t *size)
  734. {
  735. data->length = len;
  736. data->data = malloc(len);
  737. if (data->data == NULL && data->length != 0U)
  738. return (ENOMEM);
  739. memcpy(data->data, p, len);
  740. if (size)
  741. *size = len;
  742. return (0);
  743. }
  744. static int
  745. der_get_oid(const unsigned char *p, size_t len,
  746. oid *data, size_t *size)
  747. {
  748. int n;
  749. size_t oldlen = len;
  750. if (len < 1U)
  751. return (ASN1_OVERRUN);
  752. data->components = malloc(len * sizeof(*data->components));
  753. if (data->components == NULL && len != 0U)
  754. return (ENOMEM);
  755. data->components[0] = (*p) / 40;
  756. data->components[1] = (*p) % 40;
  757. --len;
  758. ++p;
  759. for (n = 2; len > 0U; ++n) {
  760. unsigned u = 0;
  761. do {
  762. --len;
  763. u = u * 128 + (*p++ % 128);
  764. } while (len > 0U && p[-1] & 0x80);
  765. data->components[n] = u;
  766. }
  767. if (p[-1] & 0x80) {
  768. free_oid(data);
  769. return (ASN1_OVERRUN);
  770. }
  771. data->length = n;
  772. if (size)
  773. *size = oldlen;
  774. return (0);
  775. }
  776. static int
  777. der_get_tag(const unsigned char *p, size_t len,
  778. Der_class *class, Der_type *type,
  779. int *tag, size_t *size)
  780. {
  781. if (len < 1U)
  782. return (ASN1_OVERRUN);
  783. *class = (Der_class) (((*p) >> 6) & 0x03);
  784. *type = (Der_type) (((*p) >> 5) & 0x01);
  785. *tag = (*p) & 0x1F;
  786. if (size)
  787. *size = 1;
  788. return (0);
  789. }
  790. static int
  791. der_match_tag(const unsigned char *p, size_t len,
  792. Der_class class, Der_type type,
  793. int tag, size_t *size)
  794. {
  795. size_t l;
  796. Der_class thisclass;
  797. Der_type thistype;
  798. int thistag;
  799. int e;
  800. e = der_get_tag(p, len, &thisclass, &thistype, &thistag, &l);
  801. if (e)
  802. return (e);
  803. if (class != thisclass || type != thistype)
  804. return (ASN1_BAD_ID);
  805. if (tag > thistag)
  806. return (ASN1_MISPLACED_FIELD);
  807. if (tag < thistag)
  808. return (ASN1_MISSING_FIELD);
  809. if (size)
  810. *size = l;
  811. return (0);
  812. }
  813. static int
  814. der_match_tag_and_length(const unsigned char *p, size_t len,
  815. Der_class class, Der_type type, int tag,
  816. size_t *length_ret, size_t *size)
  817. {
  818. size_t l, ret = 0;
  819. int e;
  820. e = der_match_tag(p, len, class, type, tag, &l);
  821. if (e)
  822. return (e);
  823. p += l;
  824. len -= l;
  825. ret += l;
  826. e = der_get_length(p, len, length_ret, &l);
  827. if (e)
  828. return (e);
  829. /* p += l; */
  830. len -= l;
  831. POST(len);
  832. ret += l;
  833. if (size)
  834. *size = ret;
  835. return (0);
  836. }
  837. static int
  838. decode_enumerated(const unsigned char *p, size_t len, void *num, size_t *size)
  839. {
  840. size_t ret = 0;
  841. size_t l, reallen;
  842. int e;
  843. e = der_match_tag(p, len, ASN1_C_UNIV, PRIM, UT_Enumerated, &l);
  844. if (e)
  845. return (e);
  846. p += l;
  847. len -= l;
  848. ret += l;
  849. e = der_get_length(p, len, &reallen, &l);
  850. if (e)
  851. return (e);
  852. p += l;
  853. len -= l;
  854. ret += l;
  855. e = der_get_int(p, reallen, num, &l);
  856. if (e)
  857. return (e);
  858. p += l;
  859. len -= l;
  860. POST(p); POST(len);
  861. ret += l;
  862. if (size)
  863. *size = ret;
  864. return (0);
  865. }
  866. static int
  867. decode_octet_string(const unsigned char *p, size_t len,
  868. octet_string *k, size_t *size)
  869. {
  870. size_t ret = 0;
  871. size_t l;
  872. int e;
  873. size_t slen;
  874. e = der_match_tag(p, len, ASN1_C_UNIV, PRIM, UT_OctetString, &l);
  875. if (e)
  876. return (e);
  877. p += l;
  878. len -= l;
  879. ret += l;
  880. e = der_get_length(p, len, &slen, &l);
  881. if (e)
  882. return (e);
  883. p += l;
  884. len -= l;
  885. ret += l;
  886. if (len < slen)
  887. return (ASN1_OVERRUN);
  888. e = der_get_octet_string(p, slen, k, &l);
  889. if (e)
  890. return (e);
  891. p += l;
  892. len -= l;
  893. POST(p); POST(len);
  894. ret += l;
  895. if (size)
  896. *size = ret;
  897. return (0);
  898. }
  899. static int
  900. decode_oid(const unsigned char *p, size_t len,
  901. oid *k, size_t *size)
  902. {
  903. size_t ret = 0;
  904. size_t l;
  905. int e;
  906. size_t slen;
  907. e = der_match_tag(p, len, ASN1_C_UNIV, PRIM, UT_OID, &l);
  908. if (e)
  909. return (e);
  910. p += l;
  911. len -= l;
  912. ret += l;
  913. e = der_get_length(p, len, &slen, &l);
  914. if (e)
  915. return (e);
  916. p += l;
  917. len -= l;
  918. ret += l;
  919. if (len < slen)
  920. return (ASN1_OVERRUN);
  921. e = der_get_oid(p, slen, k, &l);
  922. if (e)
  923. return (e);
  924. p += l;
  925. len -= l;
  926. POST(p); POST(len);
  927. ret += l;
  928. if (size)
  929. *size = ret;
  930. return (0);
  931. }
  932. static int
  933. fix_dce(size_t reallen, size_t *len)
  934. {
  935. if (reallen == ASN1_INDEFINITE)
  936. return (1);
  937. if (*len < reallen)
  938. return (-1);
  939. *len = reallen;
  940. return (0);
  941. }
  942. /* der_length.c */
  943. static size_t
  944. len_unsigned(unsigned val)
  945. {
  946. size_t ret = 0;
  947. do {
  948. ++ret;
  949. val /= 256;
  950. } while (val);
  951. return (ret);
  952. }
  953. static size_t
  954. length_len(size_t len)
  955. {
  956. if (len < 128U)
  957. return (1);
  958. else
  959. return (len_unsigned(len) + 1);
  960. }
  961. /* der_put.c */
  962. /*
  963. * All encoding functions take a pointer `p' to first position in which to
  964. * write, from the right, `len' which means the maximum number of characters
  965. * we are able to write. The function returns the number of characters
  966. * written in `size' (if non-NULL). The return value is 0 or an error.
  967. */
  968. static int
  969. der_put_unsigned(unsigned char *p, size_t len, unsigned val, size_t *size)
  970. {
  971. unsigned char *base = p;
  972. if (val) {
  973. while (len > 0U && val) {
  974. *p-- = val % 256;
  975. val /= 256;
  976. --len;
  977. }
  978. if (val != 0)
  979. return (ASN1_OVERFLOW);
  980. else {
  981. *size = base - p;
  982. return (0);
  983. }
  984. } else if (len < 1U)
  985. return (ASN1_OVERFLOW);
  986. else {
  987. *p = 0;
  988. *size = 1;
  989. return (0);
  990. }
  991. }
  992. static int
  993. der_put_int(unsigned char *p, size_t len, int val, size_t *size)
  994. {
  995. unsigned char *base = p;
  996. if (val >= 0) {
  997. do {
  998. if (len < 1U)
  999. return (ASN1_OVERFLOW);
  1000. *p-- = val % 256;
  1001. len--;
  1002. val /= 256;
  1003. } while (val);
  1004. if (p[1] >= 128) {
  1005. if (len < 1U)
  1006. return (ASN1_OVERFLOW);
  1007. *p-- = 0;
  1008. len--;
  1009. }
  1010. } else {
  1011. val = ~val;
  1012. do {
  1013. if (len < 1U)
  1014. return (ASN1_OVERFLOW);
  1015. *p-- = ~(val % 256);
  1016. len--;
  1017. val /= 256;
  1018. } while (val);
  1019. if (p[1] < 128) {
  1020. if (len < 1U)
  1021. return (ASN1_OVERFLOW);
  1022. *p-- = 0xff;
  1023. len--;
  1024. }
  1025. }
  1026. *size = base - p;
  1027. return (0);
  1028. }
  1029. static int
  1030. der_put_length(unsigned char *p, size_t len, size_t val, size_t *size)
  1031. {
  1032. if (len < 1U)
  1033. return (ASN1_OVERFLOW);
  1034. if (val < 128U) {
  1035. *p = val;
  1036. *size = 1;
  1037. return (0);
  1038. } else {
  1039. size_t l;
  1040. int e;
  1041. e = der_put_unsigned(p, len - 1, val, &l);
  1042. if (e)
  1043. return (e);
  1044. p -= l;
  1045. *p = 0x80 | l;
  1046. *size = l + 1;
  1047. return (0);
  1048. }
  1049. }
  1050. static int
  1051. der_put_octet_string(unsigned char *p, size_t len,
  1052. const octet_string *data, size_t *size)
  1053. {
  1054. if (len < data->length)
  1055. return (ASN1_OVERFLOW);
  1056. p -= data->length;
  1057. len -= data->length;
  1058. POST(len);
  1059. memcpy(p + 1, data->data, data->length);
  1060. *size = data->length;
  1061. return (0);
  1062. }
  1063. static int
  1064. der_put_oid(unsigned char *p, size_t len,
  1065. const oid *data, size_t *size)
  1066. {
  1067. unsigned char *base = p;
  1068. int n;
  1069. for (n = data->length - 1; n >= 2; --n) {
  1070. unsigned u = data->components[n];
  1071. if (len < 1U)
  1072. return (ASN1_OVERFLOW);
  1073. *p-- = u % 128;
  1074. u /= 128;
  1075. --len;
  1076. while (u > 0) {
  1077. if (len < 1U)
  1078. return (ASN1_OVERFLOW);
  1079. *p-- = 128 + u % 128;
  1080. u /= 128;
  1081. --len;
  1082. }
  1083. }
  1084. if (len < 1U)
  1085. return (ASN1_OVERFLOW);
  1086. *p-- = 40 * data->components[0] + data->components[1];
  1087. *size = base - p;
  1088. return (0);
  1089. }
  1090. static int
  1091. der_put_tag(unsigned char *p, size_t len, Der_class class, Der_type type,
  1092. int tag, size_t *size)
  1093. {
  1094. if (len < 1U)
  1095. return (ASN1_OVERFLOW);
  1096. *p = (class << 6) | (type << 5) | tag; /* XXX */
  1097. *size = 1;
  1098. return (0);
  1099. }
  1100. static int
  1101. der_put_length_and_tag(unsigned char *p, size_t len, size_t len_val,
  1102. Der_class class, Der_type type, int tag, size_t *size)
  1103. {
  1104. size_t ret = 0;
  1105. size_t l;
  1106. int e;
  1107. e = der_put_length(p, len, len_val, &l);
  1108. if (e)
  1109. return (e);
  1110. p -= l;
  1111. len -= l;
  1112. ret += l;
  1113. e = der_put_tag(p, len, class, type, tag, &l);
  1114. if (e)
  1115. return (e);
  1116. p -= l;
  1117. len -= l;
  1118. POST(p); POST(len);
  1119. ret += l;
  1120. *size = ret;
  1121. return (0);
  1122. }
  1123. static int
  1124. encode_enumerated(unsigned char *p, size_t len, const void *data, size_t *size)
  1125. {
  1126. unsigned num = *(const unsigned *)data;
  1127. size_t ret = 0;
  1128. size_t l;
  1129. int e;
  1130. e = der_put_int(p, len, num, &l);
  1131. if (e)
  1132. return (e);
  1133. p -= l;
  1134. len -= l;
  1135. ret += l;
  1136. e = der_put_length_and_tag(p, len, l, ASN1_C_UNIV, PRIM, UT_Enumerated, &l);
  1137. if (e)
  1138. return (e);
  1139. p -= l;
  1140. len -= l;
  1141. POST(p); POST(len);
  1142. ret += l;
  1143. *size = ret;
  1144. return (0);
  1145. }
  1146. static int
  1147. encode_octet_string(unsigned char *p, size_t len,
  1148. const octet_string *k, size_t *size)
  1149. {
  1150. size_t ret = 0;
  1151. size_t l;
  1152. int e;
  1153. e = der_put_octet_string(p, len, k, &l);
  1154. if (e)
  1155. return (e);
  1156. p -= l;
  1157. len -= l;
  1158. ret += l;
  1159. e = der_put_length_and_tag(p, len, l, ASN1_C_UNIV, PRIM, UT_OctetString, &l);
  1160. if (e)
  1161. return (e);
  1162. p -= l;
  1163. len -= l;
  1164. POST(p); POST(len);
  1165. ret += l;
  1166. *size = ret;
  1167. return (0);
  1168. }
  1169. static int
  1170. encode_oid(unsigned char *p, size_t len,
  1171. const oid *k, size_t *size)
  1172. {
  1173. size_t ret = 0;
  1174. size_t l;
  1175. int e;
  1176. e = der_put_oid(p, len, k, &l);
  1177. if (e)
  1178. return (e);
  1179. p -= l;
  1180. len -= l;
  1181. ret += l;
  1182. e = der_put_length_and_tag(p, len, l, ASN1_C_UNIV, PRIM, UT_OID, &l);
  1183. if (e)
  1184. return (e);
  1185. p -= l;
  1186. len -= l;
  1187. POST(p); POST(len);
  1188. ret += l;
  1189. *size = ret;
  1190. return (0);
  1191. }
  1192. /* encapsulate.c */
  1193. static void
  1194. gssapi_encap_length(size_t data_len,
  1195. size_t *len,
  1196. size_t *total_len,
  1197. const gss_OID mech)
  1198. {
  1199. size_t len_len;
  1200. *len = 1 + 1 + mech->length + data_len;
  1201. len_len = length_len(*len);
  1202. *total_len = 1 + len_len + *len;
  1203. }
  1204. static u_char *
  1205. gssapi_mech_make_header(u_char *p,
  1206. size_t len,
  1207. const gss_OID mech)
  1208. {
  1209. int e;
  1210. size_t len_len, foo;
  1211. *p++ = 0x60;
  1212. len_len = length_len(len);
  1213. e = der_put_length(p + len_len - 1, len_len, len, &foo);
  1214. if (e || foo != len_len)
  1215. return (NULL);
  1216. p += len_len;
  1217. *p++ = 0x06;
  1218. *p++ = mech->length;
  1219. memcpy(p, mech->elements, mech->length);
  1220. p += mech->length;
  1221. return (p);
  1222. }
  1223. /*
  1224. * Give it a krb5_data and it will encapsulate with extra GSS-API wrappings.
  1225. */
  1226. static OM_uint32
  1227. gssapi_spnego_encapsulate(OM_uint32 * minor_status,
  1228. unsigned char *buf,
  1229. size_t buf_size,
  1230. gss_buffer_t output_token,
  1231. const gss_OID mech)
  1232. {
  1233. size_t len, outer_len;
  1234. u_char *p;
  1235. gssapi_encap_length(buf_size, &len, &outer_len, mech);
  1236. output_token->length = outer_len;
  1237. output_token->value = malloc(outer_len);
  1238. if (output_token->value == NULL) {
  1239. *minor_status = ENOMEM;
  1240. return (GSS_S_FAILURE);
  1241. }
  1242. p = gssapi_mech_make_header(output_token->value, len, mech);
  1243. if (p == NULL) {
  1244. if (output_token->length != 0U)
  1245. gss_release_buffer(minor_status, output_token);
  1246. return (GSS_S_FAILURE);
  1247. }
  1248. memcpy(p, buf, buf_size);
  1249. return (GSS_S_COMPLETE);
  1250. }
  1251. /* init_sec_context.c */
  1252. /*
  1253. * SPNEGO wrapper for Kerberos5 GSS-API kouril@ics.muni.cz, 2003 (mostly
  1254. * based on Heimdal code)
  1255. */
  1256. static int
  1257. add_mech(MechTypeList * mech_list, gss_OID mech)
  1258. {
  1259. MechType *tmp;
  1260. int ret;
  1261. tmp = realloc(mech_list->val, (mech_list->len + 1) * sizeof(*tmp));
  1262. if (tmp == NULL)
  1263. return (ENOMEM);
  1264. mech_list->val = tmp;
  1265. ret = der_get_oid(mech->elements, mech->length,
  1266. &mech_list->val[mech_list->len], NULL);
  1267. if (ret)
  1268. return (ret);
  1269. mech_list->len++;
  1270. return (0);
  1271. }
  1272. /*
  1273. * return the length of the mechanism in token or -1
  1274. * (which implies that the token was bad - GSS_S_DEFECTIVE_TOKEN
  1275. */
  1276. static ssize_t
  1277. gssapi_krb5_get_mech(const u_char *ptr,
  1278. size_t total_len,
  1279. const u_char **mech_ret)
  1280. {
  1281. size_t len, len_len, mech_len, foo;
  1282. const u_char *p = ptr;
  1283. int e;
  1284. if (total_len < 1U)
  1285. return (-1);
  1286. if (*p++ != 0x60)
  1287. return (-1);
  1288. e = der_get_length (p, total_len - 1, &len, &len_len);
  1289. if (e || 1 + len_len + len != total_len)
  1290. return (-1);
  1291. p += len_len;
  1292. if (*p++ != 0x06)
  1293. return (-1);
  1294. e = der_get_length (p, total_len - 1 - len_len - 1,
  1295. &mech_len, &foo);
  1296. if (e)
  1297. return (-1);
  1298. p += foo;
  1299. *mech_ret = p;
  1300. return (mech_len);
  1301. }
  1302. static OM_uint32
  1303. spnego_initial(OM_uint32 *minor_status,
  1304. const gss_cred_id_t initiator_cred_handle,
  1305. gss_ctx_id_t *context_handle,
  1306. const gss_name_t target_name,
  1307. const gss_OID mech_type,
  1308. OM_uint32 req_flags,
  1309. OM_uint32 time_req,
  1310. const gss_channel_bindings_t input_chan_bindings,
  1311. const gss_buffer_t input_token,
  1312. gss_OID *actual_mech_type,
  1313. gss_buffer_t output_token,
  1314. OM_uint32 *ret_flags,
  1315. OM_uint32 *time_rec)
  1316. {
  1317. NegTokenInit token_init;
  1318. OM_uint32 major_status, minor_status2;
  1319. gss_buffer_desc krb5_output_token = GSS_C_EMPTY_BUFFER;
  1320. unsigned char *buf = NULL;
  1321. size_t buf_size;
  1322. size_t len;
  1323. int ret;
  1324. (void)mech_type;
  1325. memset(&token_init, 0, sizeof(token_init));
  1326. ret = add_mech(&token_init.mechTypes, GSS_KRB5_MECH);
  1327. if (ret) {
  1328. *minor_status = ret;
  1329. ret = GSS_S_FAILURE;
  1330. goto end;
  1331. }
  1332. major_status = gss_init_sec_context(minor_status,
  1333. initiator_cred_handle,
  1334. context_handle,
  1335. target_name,
  1336. GSS_KRB5_MECH,
  1337. req_flags,
  1338. time_req,
  1339. input_chan_bindings,
  1340. input_token,
  1341. actual_mech_type,
  1342. &krb5_output_token,
  1343. ret_flags,
  1344. time_rec);
  1345. if (GSS_ERROR(major_status)) {
  1346. ret = major_status;
  1347. goto end;
  1348. }
  1349. if (krb5_output_token.length > 0U) {
  1350. token_init.mechToken = malloc(sizeof(*token_init.mechToken));
  1351. if (token_init.mechToken == NULL) {
  1352. *minor_status = ENOMEM;
  1353. ret = GSS_S_FAILURE;
  1354. goto end;
  1355. }
  1356. token_init.mechToken->data = krb5_output_token.value;
  1357. token_init.mechToken->length = krb5_output_token.length;
  1358. }
  1359. /*
  1360. * The MS implementation of SPNEGO seems to not like the mechListMIC
  1361. * field, so we omit it (it's optional anyway)
  1362. */
  1363. buf_size = 1024;
  1364. buf = malloc(buf_size);
  1365. do {
  1366. ret = encode_NegTokenInit(buf + buf_size - 1,
  1367. buf_size,
  1368. &token_init, &len);
  1369. if (ret == 0) {
  1370. size_t tmp;
  1371. ret = der_put_length_and_tag(buf + buf_size - len - 1,
  1372. buf_size - len,
  1373. len,
  1374. ASN1_C_CONTEXT,
  1375. CONS,
  1376. 0,
  1377. &tmp);
  1378. if (ret == 0)
  1379. len += tmp;
  1380. }
  1381. if (ret) {
  1382. if (ret == ASN1_OVERFLOW) {
  1383. u_char *tmp;
  1384. buf_size *= 2;
  1385. tmp = realloc(buf, buf_size);
  1386. if (tmp == NULL) {
  1387. *minor_status = ENOMEM;
  1388. ret = GSS_S_FAILURE;
  1389. goto end;
  1390. }
  1391. buf = tmp;
  1392. } else {
  1393. *minor_status = ret;
  1394. ret = GSS_S_FAILURE;
  1395. goto end;
  1396. }
  1397. }
  1398. } while (ret == ASN1_OVERFLOW);
  1399. ret = gssapi_spnego_encapsulate(minor_status,
  1400. buf + buf_size - len, len,
  1401. output_token, GSS_SPNEGO_MECH);
  1402. if (ret == GSS_S_COMPLETE)
  1403. ret = major_status;
  1404. end:
  1405. if (token_init.mechToken != NULL) {
  1406. free(token_init.mechToken);
  1407. token_init.mechToken = NULL;
  1408. }
  1409. free_NegTokenInit(&token_init);
  1410. if (krb5_output_token.length != 0U)
  1411. gss_release_buffer(&minor_status2, &krb5_output_token);
  1412. if (buf)
  1413. free(buf);
  1414. return (ret);
  1415. }
  1416. static OM_uint32
  1417. spnego_reply(OM_uint32 *minor_status,
  1418. const gss_cred_id_t initiator_cred_handle,
  1419. gss_ctx_id_t *context_handle,
  1420. const gss_name_t target_name,
  1421. const gss_OID mech_type,
  1422. OM_uint32 req_flags,
  1423. OM_uint32 time_req,
  1424. const gss_channel_bindings_t input_chan_bindings,
  1425. const gss_buffer_t input_token,
  1426. gss_OID *actual_mech_type,
  1427. gss_buffer_t output_token,
  1428. OM_uint32 *ret_flags,
  1429. OM_uint32 *time_rec)
  1430. {
  1431. OM_uint32 ret;
  1432. NegTokenResp resp;
  1433. unsigned char *buf;
  1434. size_t buf_size;
  1435. u_char oidbuf[17];
  1436. size_t oidlen;
  1437. gss_buffer_desc sub_token;
  1438. ssize_t mech_len;
  1439. const u_char *p;
  1440. size_t len, taglen;
  1441. (void)mech_type;
  1442. output_token->length = 0;
  1443. output_token->value = NULL;
  1444. /*
  1445. * SPNEGO doesn't include gss wrapping on SubsequentContextToken
  1446. * like the Kerberos 5 mech does. But lets check for it anyway.
  1447. */
  1448. mech_len = gssapi_krb5_get_mech(input_token->value,
  1449. input_token->length,
  1450. &p);
  1451. if (mech_len < 0) {
  1452. buf = input_token->value;
  1453. buf_size = input_token->length;
  1454. } else if ((size_t)mech_len == GSS_KRB5_MECH->length &&
  1455. memcmp(GSS_KRB5_MECH->elements, p, mech_len) == 0)
  1456. return (gss_init_sec_context(minor_status,
  1457. initiator_cred_handle,
  1458. context_handle,
  1459. target_name,
  1460. GSS_KRB5_MECH,
  1461. req_flags,
  1462. time_req,
  1463. input_chan_bindings,
  1464. input_token,
  1465. actual_mech_type,
  1466. output_token,
  1467. ret_flags,
  1468. time_rec));
  1469. else if ((size_t)mech_len == GSS_SPNEGO_MECH->length &&
  1470. memcmp(GSS_SPNEGO_MECH->elements, p, mech_len) == 0) {
  1471. ret = gssapi_spnego_decapsulate(minor_status,
  1472. input_token,
  1473. &buf,
  1474. &buf_size,
  1475. GSS_SPNEGO_MECH);
  1476. if (ret)
  1477. return (ret);
  1478. } else
  1479. return (GSS_S_BAD_MECH);
  1480. ret = der_match_tag_and_length(buf, buf_size,
  1481. ASN1_C_CONTEXT, CONS, 1, &len, &taglen);
  1482. if (ret)
  1483. return (ret);
  1484. if(len > buf_size - taglen)
  1485. return (ASN1_OVERRUN);
  1486. ret = decode_NegTokenResp(buf + taglen, len, &resp, NULL);
  1487. if (ret) {
  1488. *minor_status = ENOMEM;
  1489. return (GSS_S_FAILURE);
  1490. }
  1491. if (resp.negState == NULL ||
  1492. *(resp.negState) == reject ||
  1493. resp.supportedMech == NULL) {
  1494. free_NegTokenResp(&resp);
  1495. return (GSS_S_BAD_MECH);
  1496. }
  1497. ret = der_put_oid(oidbuf + sizeof(oidbuf) - 1,
  1498. sizeof(oidbuf),
  1499. resp.supportedMech,
  1500. &oidlen);
  1501. if (ret || oidlen != GSS_KRB5_MECH->length ||
  1502. memcmp(oidbuf + sizeof(oidbuf) - oidlen,
  1503. GSS_KRB5_MECH->elements,
  1504. oidlen) != 0) {
  1505. free_NegTokenResp(&resp);
  1506. return GSS_S_BAD_MECH;
  1507. }
  1508. if (resp.responseToken != NULL) {
  1509. sub_token.length = resp.responseToken->length;
  1510. sub_token.value = resp.responseToken->data;
  1511. } else {
  1512. sub_token.length = 0;
  1513. sub_token.value = NULL;
  1514. }
  1515. ret = gss_init_sec_context(minor_status,
  1516. initiator_cred_handle,
  1517. context_handle,
  1518. target_name,
  1519. GSS_KRB5_MECH,
  1520. req_flags,
  1521. time_req,
  1522. input_chan_bindings,
  1523. &sub_token,
  1524. actual_mech_type,
  1525. output_token,
  1526. ret_flags,
  1527. time_rec);
  1528. if (ret) {
  1529. free_NegTokenResp(&resp);
  1530. return (ret);
  1531. }
  1532. /*
  1533. * XXXSRA I don't think this limited implementation ever needs
  1534. * to check the MIC -- our preferred mechanism (Kerberos)
  1535. * authenticates its own messages and is the only mechanism
  1536. * we'll accept, so if the mechanism negotiation completes
  1537. * successfully, we don't need the MIC. See RFC 4178.
  1538. */
  1539. free_NegTokenResp(&resp);
  1540. return (ret);
  1541. }
  1542. OM_uint32
  1543. gss_init_sec_context_spnego(OM_uint32 *minor_status,
  1544. const gss_cred_id_t initiator_cred_handle,
  1545. gss_ctx_id_t *context_handle,
  1546. const gss_name_t target_name,
  1547. const gss_OID mech_type,
  1548. OM_uint32 req_flags,
  1549. OM_uint32 time_req,
  1550. const gss_channel_bindings_t input_chan_bindings,
  1551. const gss_buffer_t input_token,
  1552. gss_OID *actual_mech_type,
  1553. gss_buffer_t output_token,
  1554. OM_uint32 *ret_flags,
  1555. OM_uint32 *time_rec)
  1556. {
  1557. /* Dirty trick to suppress compiler warnings */
  1558. /* Figure out whether we're starting over or processing a reply */
  1559. if (input_token == GSS_C_NO_BUFFER || input_token->length == 0U)
  1560. return (spnego_initial(minor_status,
  1561. initiator_cred_handle,
  1562. context_handle,
  1563. target_name,
  1564. mech_type,
  1565. req_flags,
  1566. time_req,
  1567. input_chan_bindings,
  1568. input_token,
  1569. actual_mech_type,
  1570. output_token,
  1571. ret_flags,
  1572. time_rec));
  1573. else
  1574. return (spnego_reply(minor_status,
  1575. initiator_cred_handle,
  1576. context_handle,
  1577. target_name,
  1578. mech_type,
  1579. req_flags,
  1580. time_req,
  1581. input_chan_bindings,
  1582. input_token,
  1583. actual_mech_type,
  1584. output_token,
  1585. ret_flags,
  1586. time_rec));
  1587. }
  1588. #endif /* GSSAPI */