1 /*-
2 * Copyright (c) 2005 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: src/lib/libgssapi/gss_mech_switch.c,v 1.2 2006/02/04 09:40:21 dfr Exp $
27 */
28
29 #include "mech_locl.h"
30 #include <heim_threads.h>
31
32 #ifndef _PATH_GSS_MECH
33 #define _PATH_GSS_MECH "/etc/gss/mech"
34 #endif
35
36 struct _gss_mech_switch_list _gss_mechs = { NULL } ;
37 gss_OID_set _gss_mech_oids;
38 static HEIMDAL_MUTEX _gss_mech_mutex = HEIMDAL_MUTEX_INITIALIZER;
39
40 /*
41 * Convert a string containing an OID in 'dot' form
42 * (e.g. 1.2.840.113554.1.2.2) to a gss_OID.
43 */
44 static int
_gss_string_to_oid(const char * s,gss_OID oid)45 _gss_string_to_oid(const char* s, gss_OID oid)
46 {
47 int number_count, i, j;
48 size_t byte_count;
49 const char *p, *q;
50 char *res;
51
52 oid->length = 0;
53 oid->elements = NULL;
54
55 /*
56 * First figure out how many numbers in the oid, then
57 * calculate the compiled oid size.
58 */
59 number_count = 0;
60 for (p = s; p; p = q) {
61 q = strchr(p, '.');
62 if (q) q = q + 1;
63 number_count++;
64 }
65
66 /*
67 * The first two numbers are in the first byte and each
68 * subsequent number is encoded in a variable byte sequence.
69 */
70 if (number_count < 2)
71 return (EINVAL);
72
73 /*
74 * We do this in two passes. The first pass, we just figure
75 * out the size. Second time around, we actually encode the
76 * number.
77 */
78 res = 0;
79 for (i = 0; i < 2; i++) {
80 byte_count = 0;
81 for (p = s, j = 0; p; p = q, j++) {
82 unsigned int number = 0;
83
84 /*
85 * Find the end of this number.
86 */
87 q = strchr(p, '.');
88 if (q) q = q + 1;
89
90 /*
91 * Read the number of of the string. Don't
92 * bother with anything except base ten.
93 */
94 while (*p && *p != '.') {
95 number = 10 * number + (*p - '0');
96 p++;
97 }
98
99 /*
100 * Encode the number. The first two numbers
101 * are packed into the first byte. Subsequent
102 * numbers are encoded in bytes seven bits at
103 * a time with the last byte having the high
104 * bit set.
105 */
106 if (j == 0) {
107 if (res)
108 *res = number * 40;
109 } else if (j == 1) {
110 if (res) {
111 *res += number;
112 res++;
113 }
114 byte_count++;
115 } else if (j >= 2) {
116 /*
117 * The number is encoded in seven bit chunks.
118 */
119 unsigned int t;
120 unsigned int bytes;
121
122 bytes = 0;
123 for (t = number; t; t >>= 7)
124 bytes++;
125 if (bytes == 0) bytes = 1;
126 while (bytes) {
127 if (res) {
128 int bit = 7*(bytes-1);
129
130 *res = (number >> bit) & 0x7f;
131 if (bytes != 1)
132 *res |= 0x80;
133 res++;
134 }
135 byte_count++;
136 bytes--;
137 }
138 }
139 }
140 if (!res) {
141 res = malloc(byte_count);
142 if (!res)
143 return (ENOMEM);
144 oid->length = byte_count;
145 oid->elements = res;
146 }
147 }
148
149 return (0);
150 }
151
152 #define SYM(name) \
153 do { \
154 m->gm_mech.gm_ ## name = dlsym(so, "gss_" #name); \
155 if (!m->gm_mech.gm_ ## name || \
156 m->gm_mech.gm_ ##name == gss_ ## name) { \
157 fprintf(stderr, "can't find symbol gss_" #name "\n"); \
158 goto bad; \
159 } \
160 } while (0)
161
162 #define OPTSYM(name) \
163 do { \
164 m->gm_mech.gm_ ## name = dlsym(so, "gss_" #name); \
165 if (m->gm_mech.gm_ ## name == gss_ ## name) \
166 m->gm_mech.gm_ ## name = NULL; \
167 } while (0)
168
169 #define OPTSPISYM(name) \
170 do { \
171 m->gm_mech.gm_ ## name = dlsym(so, "gssspi_" #name); \
172 } while (0)
173
174 #define COMPATSYM(name) \
175 do { \
176 m->gm_mech.gm_compat->gmc_ ## name = dlsym(so, "gss_" #name); \
177 if (m->gm_mech.gm_compat->gmc_ ## name == gss_ ## name) \
178 m->gm_mech.gm_compat->gmc_ ## name = NULL; \
179 } while (0)
180
181 #define COMPATSPISYM(name) \
182 do { \
183 m->gm_mech.gm_compat->gmc_ ## name = dlsym(so, "gssspi_" #name);\
184 if (m->gm_mech.gm_compat->gmc_ ## name == gss_ ## name) \
185 m->gm_mech.gm_compat->gmc_ ## name = NULL; \
186 } while (0)
187
188 /*
189 *
190 */
191 static int
add_builtin(gssapi_mech_interface mech)192 add_builtin(gssapi_mech_interface mech)
193 {
194 struct _gss_mech_switch *m;
195 OM_uint32 minor_status;
196
197 /* not registering any mech is ok */
198 if (mech == NULL)
199 return 0;
200
201 m = calloc(1, sizeof(*m));
202 if (m == NULL)
203 return ENOMEM;
204 m->gm_so = NULL;
205 m->gm_mech = *mech;
206 m->gm_mech_oid = mech->gm_mech_oid; /* XXX */
207 gss_add_oid_set_member(&minor_status,
208 &m->gm_mech.gm_mech_oid, &_gss_mech_oids);
209
210 /* pick up the oid sets of names */
211
212 if (m->gm_mech.gm_inquire_names_for_mech)
213 (*m->gm_mech.gm_inquire_names_for_mech)(&minor_status,
214 &m->gm_mech.gm_mech_oid, &m->gm_name_types);
215
216 if (m->gm_name_types == NULL)
217 gss_create_empty_oid_set(&minor_status, &m->gm_name_types);
218
219 HEIM_SLIST_INSERT_HEAD(&_gss_mechs, m, gm_link);
220 return 0;
221 }
222
223 /*
224 * Load the mechanisms file (/etc/gss/mech).
225 */
226 void
_gss_load_mech(void)227 _gss_load_mech(void)
228 {
229 OM_uint32 major_status, minor_status;
230 FILE *fp;
231 char buf[256];
232 char *p;
233 char *name, *oid, *lib, *kobj;
234 struct _gss_mech_switch *m;
235 void *so;
236 gss_OID_desc mech_oid;
237 int found;
238
239
240 HEIMDAL_MUTEX_lock(&_gss_mech_mutex);
241
242 if (HEIM_SLIST_FIRST(&_gss_mechs)) {
243 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
244 return;
245 }
246
247 major_status = gss_create_empty_oid_set(&minor_status,
248 &_gss_mech_oids);
249 if (major_status) {
250 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
251 return;
252 }
253
254 add_builtin(__gss_krb5_initialize());
255 add_builtin(__gss_spnego_initialize());
256 add_builtin(__gss_ntlm_initialize());
257
258 #ifdef HAVE_DLOPEN
259 fp = fopen(_PATH_GSS_MECH, "r");
260 if (!fp) {
261 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
262 return;
263 }
264 rk_cloexec_file(fp);
265
266 while (fgets(buf, sizeof(buf), fp)) {
267 _gss_mo_init *mi;
268
269 if (*buf == '#')
270 continue;
271 p = buf;
272 name = strsep(&p, "\t\n ");
273 if (p) while (isspace((unsigned char)*p)) p++;
274 oid = strsep(&p, "\t\n ");
275 if (p) while (isspace((unsigned char)*p)) p++;
276 lib = strsep(&p, "\t\n ");
277 if (p) while (isspace((unsigned char)*p)) p++;
278 kobj = strsep(&p, "\t\n ");
279 if (!name || !oid || !lib || !kobj)
280 continue;
281
282 if (_gss_string_to_oid(oid, &mech_oid))
283 continue;
284
285 /*
286 * Check for duplicates, already loaded mechs.
287 */
288 found = 0;
289 HEIM_SLIST_FOREACH(m, &_gss_mechs, gm_link) {
290 if (gss_oid_equal(&m->gm_mech.gm_mech_oid, &mech_oid)) {
291 found = 1;
292 free(mech_oid.elements);
293 break;
294 }
295 }
296 if (found)
297 continue;
298
299 #ifndef RTLD_LOCAL
300 #define RTLD_LOCAL 0
301 #endif
302
303 #ifndef RTLD_GROUP
304 #define RTLD_GROUP 0
305 #endif
306
307 so = dlopen(lib, RTLD_LAZY | RTLD_LOCAL | RTLD_GROUP);
308 if (so == NULL) {
309 /* fprintf(stderr, "dlopen: %s\n", dlerror()); */
310 goto bad;
311 }
312
313 m = calloc(1, sizeof(*m));
314 if (m == NULL)
315 goto bad;
316
317 m->gm_so = so;
318 m->gm_mech.gm_mech_oid = mech_oid;
319 m->gm_mech.gm_flags = 0;
320 m->gm_mech.gm_compat = calloc(1, sizeof(struct gss_mech_compat_desc_struct));
321 if (m->gm_mech.gm_compat == NULL)
322 goto bad;
323
324 major_status = gss_add_oid_set_member(&minor_status,
325 &m->gm_mech.gm_mech_oid, &_gss_mech_oids);
326 if (GSS_ERROR(major_status))
327 goto bad;
328
329 SYM(acquire_cred);
330 SYM(release_cred);
331 SYM(init_sec_context);
332 SYM(accept_sec_context);
333 SYM(process_context_token);
334 SYM(delete_sec_context);
335 SYM(context_time);
336 SYM(get_mic);
337 SYM(verify_mic);
338 SYM(wrap);
339 SYM(unwrap);
340 SYM(display_status);
341 SYM(indicate_mechs);
342 SYM(compare_name);
343 SYM(display_name);
344 SYM(import_name);
345 SYM(export_name);
346 SYM(release_name);
347 SYM(inquire_cred);
348 SYM(inquire_context);
349 SYM(wrap_size_limit);
350 SYM(add_cred);
351 SYM(inquire_cred_by_mech);
352 SYM(export_sec_context);
353 SYM(import_sec_context);
354 SYM(inquire_names_for_mech);
355 SYM(inquire_mechs_for_name);
356 SYM(canonicalize_name);
357 SYM(duplicate_name);
358 OPTSYM(inquire_cred_by_oid);
359 OPTSYM(inquire_sec_context_by_oid);
360 OPTSYM(set_sec_context_option);
361 OPTSPISYM(set_cred_option);
362 OPTSYM(pseudo_random);
363 OPTSYM(wrap_iov);
364 OPTSYM(unwrap_iov);
365 OPTSYM(wrap_iov_length);
366 OPTSYM(store_cred);
367 OPTSYM(export_cred);
368 OPTSYM(import_cred);
369 #if 0
370 OPTSYM(acquire_cred_ext);
371 OPTSYM(iter_creds);
372 OPTSYM(destroy_cred);
373 OPTSYM(cred_hold);
374 OPTSYM(cred_unhold);
375 OPTSYM(cred_label_get);
376 OPTSYM(cred_label_set);
377 #endif
378 OPTSYM(display_name_ext);
379 OPTSYM(inquire_name);
380 OPTSYM(get_name_attribute);
381 OPTSYM(set_name_attribute);
382 OPTSYM(delete_name_attribute);
383 OPTSYM(export_name_composite);
384 OPTSYM(pname_to_uid);
385 OPTSPISYM(authorize_localname);
386
387 mi = dlsym(so, "gss_mo_init");
388 if (mi != NULL) {
389 major_status = mi(&minor_status, &mech_oid,
390 &m->gm_mech.gm_mo, &m->gm_mech.gm_mo_num);
391 if (GSS_ERROR(major_status))
392 goto bad;
393 } else {
394 /* API-as-SPI compatibility */
395 COMPATSYM(inquire_saslname_for_mech);
396 COMPATSYM(inquire_mech_for_saslname);
397 COMPATSYM(inquire_attrs_for_mech);
398 COMPATSPISYM(acquire_cred_with_password);
399 }
400
401 /* pick up the oid sets of names */
402
403 if (m->gm_mech.gm_inquire_names_for_mech)
404 (*m->gm_mech.gm_inquire_names_for_mech)(&minor_status,
405 &m->gm_mech.gm_mech_oid, &m->gm_name_types);
406
407 if (m->gm_name_types == NULL)
408 gss_create_empty_oid_set(&minor_status, &m->gm_name_types);
409
410 HEIM_SLIST_INSERT_HEAD(&_gss_mechs, m, gm_link);
411 continue;
412
413 bad:
414 if (m != NULL) {
415 free(m->gm_mech.gm_compat);
416 free(m->gm_mech.gm_mech_oid.elements);
417 free(m);
418 }
419 dlclose(so);
420 continue;
421 }
422 fclose(fp);
423 #endif
424 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
425 }
426
427 gssapi_mech_interface
__gss_get_mechanism(gss_const_OID mech)428 __gss_get_mechanism(gss_const_OID mech)
429 {
430 struct _gss_mech_switch *m;
431
432 _gss_load_mech();
433 HEIM_SLIST_FOREACH(m, &_gss_mechs, gm_link) {
434 if (gss_oid_equal(&m->gm_mech.gm_mech_oid, mech))
435 return &m->gm_mech;
436 }
437 return NULL;
438 }
439