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 (byte_count == 0)
141 return EINVAL;
142 if (!res) {
143 res = malloc(byte_count);
144 if (!res)
145 return (ENOMEM);
146 oid->length = byte_count;
147 oid->elements = res;
148 }
149 }
150
151 return (0);
152 }
153
154 #define SYM(name) \
155 do { \
156 m->gm_mech.gm_ ## name = dlsym(so, "gss_" #name); \
157 if (!m->gm_mech.gm_ ## name || \
158 m->gm_mech.gm_ ##name == gss_ ## name) { \
159 fprintf(stderr, "can't find symbol gss_" #name "\n"); \
160 goto bad; \
161 } \
162 } while (0)
163
164 #define OPTSYM(name) \
165 do { \
166 m->gm_mech.gm_ ## name = dlsym(so, "gss_" #name); \
167 if (m->gm_mech.gm_ ## name == gss_ ## name) \
168 m->gm_mech.gm_ ## name = NULL; \
169 } while (0)
170
171 #define OPTSPISYM(name) \
172 do { \
173 m->gm_mech.gm_ ## name = dlsym(so, "gssspi_" #name); \
174 } while (0)
175
176 #define COMPATSYM(name) \
177 do { \
178 m->gm_mech.gm_compat->gmc_ ## name = dlsym(so, "gss_" #name); \
179 if (m->gm_mech.gm_compat->gmc_ ## name == gss_ ## name) \
180 m->gm_mech.gm_compat->gmc_ ## name = NULL; \
181 } while (0)
182
183 #define COMPATSPISYM(name) \
184 do { \
185 m->gm_mech.gm_compat->gmc_ ## name = dlsym(so, "gssspi_" #name);\
186 if (m->gm_mech.gm_compat->gmc_ ## name == gss_ ## name) \
187 m->gm_mech.gm_compat->gmc_ ## name = NULL; \
188 } while (0)
189
190 /*
191 *
192 */
193 static int
add_builtin(gssapi_mech_interface mech)194 add_builtin(gssapi_mech_interface mech)
195 {
196 struct _gss_mech_switch *m;
197 OM_uint32 minor_status;
198
199 /* not registering any mech is ok */
200 if (mech == NULL)
201 return 0;
202
203 m = calloc(1, sizeof(*m));
204 if (m == NULL)
205 return ENOMEM;
206 m->gm_so = NULL;
207 m->gm_mech = *mech;
208 m->gm_mech_oid = mech->gm_mech_oid; /* XXX */
209 gss_add_oid_set_member(&minor_status,
210 &m->gm_mech.gm_mech_oid, &_gss_mech_oids);
211
212 /* pick up the oid sets of names */
213
214 if (m->gm_mech.gm_inquire_names_for_mech)
215 (*m->gm_mech.gm_inquire_names_for_mech)(&minor_status,
216 &m->gm_mech.gm_mech_oid, &m->gm_name_types);
217
218 if (m->gm_name_types == NULL)
219 gss_create_empty_oid_set(&minor_status, &m->gm_name_types);
220
221 HEIM_SLIST_INSERT_HEAD(&_gss_mechs, m, gm_link);
222 return 0;
223 }
224
225 /*
226 * Load the mechanisms file (/etc/gss/mech).
227 */
228 void
_gss_load_mech(void)229 _gss_load_mech(void)
230 {
231 OM_uint32 major_status, minor_status;
232 FILE *fp;
233 char buf[256];
234 char *p;
235 char *name, *oid, *lib, *kobj;
236 struct _gss_mech_switch *m;
237 void *so;
238 gss_OID_desc mech_oid;
239 int found;
240
241
242 HEIMDAL_MUTEX_lock(&_gss_mech_mutex);
243
244 if (HEIM_SLIST_FIRST(&_gss_mechs)) {
245 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
246 return;
247 }
248
249 major_status = gss_create_empty_oid_set(&minor_status,
250 &_gss_mech_oids);
251 if (major_status) {
252 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
253 return;
254 }
255
256 add_builtin(__gss_krb5_initialize());
257 add_builtin(__gss_spnego_initialize());
258 add_builtin(__gss_ntlm_initialize());
259
260 #ifdef HAVE_DLOPEN
261 fp = fopen(_PATH_GSS_MECH, "r");
262 if (!fp) {
263 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
264 return;
265 }
266 rk_cloexec_file(fp);
267
268 while (fgets(buf, sizeof(buf), fp)) {
269 _gss_mo_init *mi;
270
271 if (*buf == '#')
272 continue;
273 p = buf;
274 name = strsep(&p, "\t\n ");
275 if (p) while (isspace((unsigned char)*p)) p++;
276 oid = strsep(&p, "\t\n ");
277 if (p) while (isspace((unsigned char)*p)) p++;
278 lib = strsep(&p, "\t\n ");
279 if (p) while (isspace((unsigned char)*p)) p++;
280 kobj = strsep(&p, "\t\n ");
281 if (!name || !oid || !lib || !kobj)
282 continue;
283
284 if (_gss_string_to_oid(oid, &mech_oid))
285 continue;
286
287 /*
288 * Check for duplicates, already loaded mechs.
289 */
290 found = 0;
291 HEIM_SLIST_FOREACH(m, &_gss_mechs, gm_link) {
292 if (gss_oid_equal(&m->gm_mech.gm_mech_oid, &mech_oid)) {
293 found = 1;
294 free(mech_oid.elements);
295 break;
296 }
297 }
298 if (found)
299 continue;
300
301 #ifndef RTLD_LOCAL
302 #define RTLD_LOCAL 0
303 #endif
304
305 #ifndef RTLD_GROUP
306 #define RTLD_GROUP 0
307 #endif
308
309 so = dlopen(lib, RTLD_LAZY | RTLD_LOCAL | RTLD_GROUP);
310 if (so == NULL) {
311 /* fprintf(stderr, "dlopen: %s\n", dlerror()); */
312 goto bad;
313 }
314
315 m = calloc(1, sizeof(*m));
316 if (m == NULL)
317 goto bad;
318
319 m->gm_so = so;
320 m->gm_mech.gm_mech_oid = mech_oid;
321 m->gm_mech.gm_flags = 0;
322 m->gm_mech.gm_compat = calloc(1, sizeof(struct gss_mech_compat_desc_struct));
323 if (m->gm_mech.gm_compat == NULL)
324 goto bad;
325
326 major_status = gss_add_oid_set_member(&minor_status,
327 &m->gm_mech.gm_mech_oid, &_gss_mech_oids);
328 if (GSS_ERROR(major_status))
329 goto bad;
330
331 SYM(acquire_cred);
332 SYM(release_cred);
333 SYM(init_sec_context);
334 SYM(accept_sec_context);
335 SYM(process_context_token);
336 SYM(delete_sec_context);
337 SYM(context_time);
338 SYM(get_mic);
339 SYM(verify_mic);
340 SYM(wrap);
341 SYM(unwrap);
342 SYM(display_status);
343 SYM(indicate_mechs);
344 SYM(compare_name);
345 SYM(display_name);
346 SYM(import_name);
347 SYM(export_name);
348 SYM(release_name);
349 SYM(inquire_cred);
350 SYM(inquire_context);
351 SYM(wrap_size_limit);
352 SYM(add_cred);
353 SYM(inquire_cred_by_mech);
354 SYM(export_sec_context);
355 SYM(import_sec_context);
356 SYM(inquire_names_for_mech);
357 SYM(inquire_mechs_for_name);
358 SYM(canonicalize_name);
359 SYM(duplicate_name);
360 OPTSYM(inquire_cred_by_oid);
361 OPTSYM(inquire_sec_context_by_oid);
362 OPTSYM(set_sec_context_option);
363 OPTSPISYM(set_cred_option);
364 OPTSYM(pseudo_random);
365 OPTSYM(wrap_iov);
366 OPTSYM(unwrap_iov);
367 OPTSYM(wrap_iov_length);
368 OPTSYM(store_cred);
369 OPTSYM(export_cred);
370 OPTSYM(import_cred);
371 #if 0
372 OPTSYM(acquire_cred_ext);
373 OPTSYM(iter_creds);
374 OPTSYM(destroy_cred);
375 OPTSYM(cred_hold);
376 OPTSYM(cred_unhold);
377 OPTSYM(cred_label_get);
378 OPTSYM(cred_label_set);
379 #endif
380 OPTSYM(display_name_ext);
381 OPTSYM(inquire_name);
382 OPTSYM(get_name_attribute);
383 OPTSYM(set_name_attribute);
384 OPTSYM(delete_name_attribute);
385 OPTSYM(export_name_composite);
386 OPTSYM(pname_to_uid);
387 OPTSPISYM(authorize_localname);
388
389 mi = dlsym(so, "gss_mo_init");
390 if (mi != NULL) {
391 major_status = mi(&minor_status, &mech_oid,
392 &m->gm_mech.gm_mo, &m->gm_mech.gm_mo_num);
393 if (GSS_ERROR(major_status))
394 goto bad;
395 } else {
396 /* API-as-SPI compatibility */
397 COMPATSYM(inquire_saslname_for_mech);
398 COMPATSYM(inquire_mech_for_saslname);
399 COMPATSYM(inquire_attrs_for_mech);
400 COMPATSPISYM(acquire_cred_with_password);
401 }
402
403 /* pick up the oid sets of names */
404
405 if (m->gm_mech.gm_inquire_names_for_mech)
406 (*m->gm_mech.gm_inquire_names_for_mech)(&minor_status,
407 &m->gm_mech.gm_mech_oid, &m->gm_name_types);
408
409 if (m->gm_name_types == NULL)
410 gss_create_empty_oid_set(&minor_status, &m->gm_name_types);
411
412 HEIM_SLIST_INSERT_HEAD(&_gss_mechs, m, gm_link);
413 continue;
414
415 bad:
416 if (m != NULL) {
417 free(m->gm_mech.gm_compat);
418 free(m->gm_mech.gm_mech_oid.elements);
419 free(m);
420 }
421 dlclose(so);
422 continue;
423 }
424 fclose(fp);
425 #endif
426 HEIMDAL_MUTEX_unlock(&_gss_mech_mutex);
427 }
428
429 gssapi_mech_interface
__gss_get_mechanism(gss_const_OID mech)430 __gss_get_mechanism(gss_const_OID mech)
431 {
432 struct _gss_mech_switch *m;
433
434 _gss_load_mech();
435 HEIM_SLIST_FOREACH(m, &_gss_mechs, gm_link) {
436 if (gss_oid_equal(&m->gm_mech.gm_mech_oid, mech))
437 return &m->gm_mech;
438 }
439 return NULL;
440 }
441