source: vendor/3.6.0/libcli/auth/spnego_parse.c

Last change on this file was 740, checked in by Silvan Scherrer, 13 years ago

Samba Server: update vendor to 3.6.0
File size: 10.2 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3
4 RFC2478 Compliant SPNEGO implementation
5
6 Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
21*/
22
23#include "includes.h"
24#include "../libcli/auth/spnego.h"
25#include "../lib/util/asn1.h"
26
27static bool read_negTokenInit(struct asn1_data *asn1, TALLOC_CTX *mem_ctx,
28 struct spnego_negTokenInit *token)
29{
30 ZERO_STRUCTP(token);
31
32 asn1_start_tag(asn1, ASN1_CONTEXT(0));
33 asn1_start_tag(asn1, ASN1_SEQUENCE(0));
34
35 while (!asn1->has_error && 0 < asn1_tag_remaining(asn1)) {
36 int i;
37 uint8_t context;
38 if (!asn1_peek_uint8(asn1, &context)) {
39 asn1->has_error = true;
40 break;
41 }
42
43 switch (context) {
44 /* Read mechTypes */
45 case ASN1_CONTEXT(0):
46 asn1_start_tag(asn1, ASN1_CONTEXT(0));
47 asn1_start_tag(asn1, ASN1_SEQUENCE(0));
48
49 token->mechTypes = talloc(NULL, const char *);
50 for (i = 0; !asn1->has_error &&
51 0 < asn1_tag_remaining(asn1); i++) {
52 char *oid;
53 token->mechTypes = talloc_realloc(NULL,
54 token->mechTypes,
55 const char *, i+2);
56 asn1_read_OID(asn1, token->mechTypes, &oid);
57 token->mechTypes[i] = oid;
58 }
59 token->mechTypes[i] = NULL;
60
61 asn1_end_tag(asn1);
62 asn1_end_tag(asn1);
63 break;
64 /* Read reqFlags */
65 case ASN1_CONTEXT(1):
66 asn1_start_tag(asn1, ASN1_CONTEXT(1));
67 asn1_read_BitString(asn1, mem_ctx, &token->reqFlags,
68 &token->reqFlagsPadding);
69 asn1_end_tag(asn1);
70 break;
71 /* Read mechToken */
72 case ASN1_CONTEXT(2):
73 asn1_start_tag(asn1, ASN1_CONTEXT(2));
74 asn1_read_OctetString(asn1, mem_ctx, &token->mechToken);
75 asn1_end_tag(asn1);
76 break;
77 /* Read mecListMIC */
78 case ASN1_CONTEXT(3):
79 {
80 uint8_t type_peek;
81 asn1_start_tag(asn1, ASN1_CONTEXT(3));
82 if (!asn1_peek_uint8(asn1, &type_peek)) {
83 asn1->has_error = true;
84 break;
85 }
86 if (type_peek == ASN1_OCTET_STRING) {
87 asn1_read_OctetString(asn1, mem_ctx,
88 &token->mechListMIC);
89 } else {
90 /* RFC 2478 says we have an Octet String here,
91 but W2k sends something different... */
92 char *mechListMIC;
93 asn1_start_tag(asn1, ASN1_SEQUENCE(0));
94 asn1_start_tag(asn1, ASN1_CONTEXT(0));
95 asn1_read_GeneralString(asn1, mem_ctx, &mechListMIC);
96 asn1_end_tag(asn1);
97 asn1_end_tag(asn1);
98
99 token->targetPrincipal = mechListMIC;
100 }
101 asn1_end_tag(asn1);
102 break;
103 }
104 default:
105 asn1->has_error = true;
106 break;
107 }
108 }
109
110 asn1_end_tag(asn1);
111 asn1_end_tag(asn1);
112
113 return !asn1->has_error;
114}
115
116static bool write_negTokenInit(struct asn1_data *asn1, struct spnego_negTokenInit *token)
117{
118 asn1_push_tag(asn1, ASN1_CONTEXT(0));
119 asn1_push_tag(asn1, ASN1_SEQUENCE(0));
120
121 /* Write mechTypes */
122 if (token->mechTypes && *token->mechTypes) {
123 int i;
124
125 asn1_push_tag(asn1, ASN1_CONTEXT(0));
126 asn1_push_tag(asn1, ASN1_SEQUENCE(0));
127 for (i = 0; token->mechTypes[i]; i++) {
128 asn1_write_OID(asn1, token->mechTypes[i]);
129 }
130 asn1_pop_tag(asn1);
131 asn1_pop_tag(asn1);
132 }
133
134 /* write reqFlags */
135 if (token->reqFlags.length > 0) {
136 asn1_push_tag(asn1, ASN1_CONTEXT(1));
137 asn1_write_BitString(asn1, token->reqFlags.data,
138 token->reqFlags.length,
139 token->reqFlagsPadding);
140 asn1_pop_tag(asn1);
141 }
142
143 /* write mechToken */
144 if (token->mechToken.data) {
145 asn1_push_tag(asn1, ASN1_CONTEXT(2));
146 asn1_write_OctetString(asn1, token->mechToken.data,
147 token->mechToken.length);
148 asn1_pop_tag(asn1);
149 }
150
151 /* write mechListMIC */
152 if (token->mechListMIC.data) {
153 asn1_push_tag(asn1, ASN1_CONTEXT(3));
154#if 0
155 /* This is what RFC 2478 says ... */
156 asn1_write_OctetString(asn1, token->mechListMIC.data,
157 token->mechListMIC.length);
158#else
159 /* ... but unfortunately this is what Windows
160 sends/expects */
161 asn1_push_tag(asn1, ASN1_SEQUENCE(0));
162 asn1_push_tag(asn1, ASN1_CONTEXT(0));
163 asn1_push_tag(asn1, ASN1_GENERAL_STRING);
164 asn1_write(asn1, token->mechListMIC.data,
165 token->mechListMIC.length);
166 asn1_pop_tag(asn1);
167 asn1_pop_tag(asn1);
168 asn1_pop_tag(asn1);
169#endif
170 asn1_pop_tag(asn1);
171 }
172
173 asn1_pop_tag(asn1);
174 asn1_pop_tag(asn1);
175
176 return !asn1->has_error;
177}
178
179static bool read_negTokenTarg(struct asn1_data *asn1, TALLOC_CTX *mem_ctx,
180 struct spnego_negTokenTarg *token)
181{
182 ZERO_STRUCTP(token);
183
184 asn1_start_tag(asn1, ASN1_CONTEXT(1));
185 asn1_start_tag(asn1, ASN1_SEQUENCE(0));
186
187 while (!asn1->has_error && 0 < asn1_tag_remaining(asn1)) {
188 uint8_t context;
189 char *oid;
190 if (!asn1_peek_uint8(asn1, &context)) {
191 asn1->has_error = true;
192 break;
193 }
194
195 switch (context) {
196 case ASN1_CONTEXT(0):
197 asn1_start_tag(asn1, ASN1_CONTEXT(0));
198 asn1_start_tag(asn1, ASN1_ENUMERATED);
199 asn1_read_uint8(asn1, &token->negResult);
200 asn1_end_tag(asn1);
201 asn1_end_tag(asn1);
202 break;
203 case ASN1_CONTEXT(1):
204 asn1_start_tag(asn1, ASN1_CONTEXT(1));
205 asn1_read_OID(asn1, mem_ctx, &oid);
206 token->supportedMech = oid;
207 asn1_end_tag(asn1);
208 break;
209 case ASN1_CONTEXT(2):
210 asn1_start_tag(asn1, ASN1_CONTEXT(2));
211 asn1_read_OctetString(asn1, mem_ctx, &token->responseToken);
212 asn1_end_tag(asn1);
213 break;
214 case ASN1_CONTEXT(3):
215 asn1_start_tag(asn1, ASN1_CONTEXT(3));
216 asn1_read_OctetString(asn1, mem_ctx, &token->mechListMIC);
217 asn1_end_tag(asn1);
218 break;
219 default:
220 asn1->has_error = true;
221 break;
222 }
223 }
224
225 asn1_end_tag(asn1);
226 asn1_end_tag(asn1);
227
228 return !asn1->has_error;
229}
230
231static bool write_negTokenTarg(struct asn1_data *asn1, struct spnego_negTokenTarg *token)
232{
233 asn1_push_tag(asn1, ASN1_CONTEXT(1));
234 asn1_push_tag(asn1, ASN1_SEQUENCE(0));
235
236 if (token->negResult != SPNEGO_NONE_RESULT) {
237 asn1_push_tag(asn1, ASN1_CONTEXT(0));
238 asn1_write_enumerated(asn1, token->negResult);
239 asn1_pop_tag(asn1);
240 }
241
242 if (token->supportedMech) {
243 asn1_push_tag(asn1, ASN1_CONTEXT(1));
244 asn1_write_OID(asn1, token->supportedMech);
245 asn1_pop_tag(asn1);
246 }
247
248 if (token->responseToken.data) {
249 asn1_push_tag(asn1, ASN1_CONTEXT(2));
250 asn1_write_OctetString(asn1, token->responseToken.data,
251 token->responseToken.length);
252 asn1_pop_tag(asn1);
253 }
254
255 if (token->mechListMIC.data) {
256 asn1_push_tag(asn1, ASN1_CONTEXT(3));
257 asn1_write_OctetString(asn1, token->mechListMIC.data,
258 token->mechListMIC.length);
259 asn1_pop_tag(asn1);
260 }
261
262 asn1_pop_tag(asn1);
263 asn1_pop_tag(asn1);
264
265 return !asn1->has_error;
266}
267
268ssize_t spnego_read_data(TALLOC_CTX *mem_ctx, DATA_BLOB data, struct spnego_data *token)
269{
270 struct asn1_data *asn1;
271 ssize_t ret = -1;
272 uint8_t context;
273
274 ZERO_STRUCTP(token);
275
276 if (data.length == 0) {
277 return ret;
278 }
279
280 asn1 = asn1_init(mem_ctx);
281 if (asn1 == NULL) {
282 return -1;
283 }
284
285 asn1_load(asn1, data);
286
287 if (!asn1_peek_uint8(asn1, &context)) {
288 asn1->has_error = true;
289 } else {
290 switch (context) {
291 case ASN1_APPLICATION(0):
292 asn1_start_tag(asn1, ASN1_APPLICATION(0));
293 asn1_check_OID(asn1, OID_SPNEGO);
294 if (read_negTokenInit(asn1, mem_ctx, &token->negTokenInit)) {
295 token->type = SPNEGO_NEG_TOKEN_INIT;
296 }
297 asn1_end_tag(asn1);
298 break;
299 case ASN1_CONTEXT(1):
300 if (read_negTokenTarg(asn1, mem_ctx, &token->negTokenTarg)) {
301 token->type = SPNEGO_NEG_TOKEN_TARG;
302 }
303 break;
304 default:
305 asn1->has_error = true;
306 break;
307 }
308 }
309
310 if (!asn1->has_error) ret = asn1->ofs;
311 asn1_free(asn1);
312
313 return ret;
314}
315
316ssize_t spnego_write_data(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, struct spnego_data *spnego)
317{
318 struct asn1_data *asn1 = asn1_init(mem_ctx);
319 ssize_t ret = -1;
320
321 if (asn1 == NULL) {
322 return -1;
323 }
324
325 switch (spnego->type) {
326 case SPNEGO_NEG_TOKEN_INIT:
327 asn1_push_tag(asn1, ASN1_APPLICATION(0));
328 asn1_write_OID(asn1, OID_SPNEGO);
329 write_negTokenInit(asn1, &spnego->negTokenInit);
330 asn1_pop_tag(asn1);
331 break;
332 case SPNEGO_NEG_TOKEN_TARG:
333 write_negTokenTarg(asn1, &spnego->negTokenTarg);
334 break;
335 default:
336 asn1->has_error = true;
337 break;
338 }
339
340 if (!asn1->has_error) {
341 *blob = data_blob_talloc(mem_ctx, asn1->data, asn1->length);
342 ret = asn1->ofs;
343 }
344 asn1_free(asn1);
345
346 return ret;
347}
348
349bool spnego_free_data(struct spnego_data *spnego)
350{
351 bool ret = true;
352
353 if (!spnego) goto out;
354
355 switch(spnego->type) {
356 case SPNEGO_NEG_TOKEN_INIT:
357 if (spnego->negTokenInit.mechTypes) {
358 talloc_free(spnego->negTokenInit.mechTypes);
359 }
360 data_blob_free(&spnego->negTokenInit.reqFlags);
361 data_blob_free(&spnego->negTokenInit.mechToken);
362 data_blob_free(&spnego->negTokenInit.mechListMIC);
363 talloc_free(spnego->negTokenInit.targetPrincipal);
364 break;
365 case SPNEGO_NEG_TOKEN_TARG:
366 if (spnego->negTokenTarg.supportedMech) {
367 talloc_free(discard_const(spnego->negTokenTarg.supportedMech));
368 }
369 data_blob_free(&spnego->negTokenTarg.responseToken);
370 data_blob_free(&spnego->negTokenTarg.mechListMIC);
371 break;
372 default:
373 ret = false;
374 break;
375 }
376 ZERO_STRUCTP(spnego);
377out:
378 return ret;
379}
380
381bool spnego_write_mech_types(TALLOC_CTX *mem_ctx,
382 const char **mech_types,
383 DATA_BLOB *blob)
384{
385 struct asn1_data *asn1 = asn1_init(mem_ctx);
386
387 if (asn1 == NULL) {
388 return false;
389 }
390
391 /* Write mechTypes */
392 if (mech_types && *mech_types) {
393 int i;
394
395 asn1_push_tag(asn1, ASN1_SEQUENCE(0));
396 for (i = 0; mech_types[i]; i++) {
397 asn1_write_OID(asn1, mech_types[i]);
398 }
399 asn1_pop_tag(asn1);
400 }
401
402 if (asn1->has_error) {
403 asn1_free(asn1);
404 return false;
405 }
406
407 *blob = data_blob_talloc(mem_ctx, asn1->data, asn1->length);
408 if (blob->length != asn1->length) {
409 asn1_free(asn1);
410 return false;
411 }
412
413 asn1_free(asn1);
414
415 return true;
416}
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