xref: /freebsd/lib/librpcsec_gss/rpcsec_gss_conf.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008 Doug Rabson
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	$FreeBSD$
29  */
30 
31 #include <ctype.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <stdlib.h>
35 #include <errno.h>
36 #include <sys/queue.h>
37 #include <rpc/rpc.h>
38 #include <rpc/rpcsec_gss.h>
39 
40 #include "rpcsec_gss_int.h"
41 
42 #ifndef _PATH_GSS_MECH
43 #define _PATH_GSS_MECH	"/etc/gss/mech"
44 #endif
45 
46 #ifndef _PATH_GSS_QOP
47 #define _PATH_GSS_QOP	"/etc/gss/qop"
48 #endif
49 
50 struct mech_info {
51 	SLIST_ENTRY(mech_info) link;
52 	char		*name;
53 	gss_OID_desc	oid;
54 	const char	**qops;
55 	char		*lib;
56 	char		*kobj;
57 };
58 SLIST_HEAD(mech_info_list, mech_info);
59 
60 static struct mech_info_list mechs = SLIST_HEAD_INITIALIZER(mechs);
61 static const char **mech_names;
62 
63 struct qop_info {
64 	SLIST_ENTRY(qop_info) link;
65 	char		*name;
66 	char*		mech;
67 	u_int		qop;
68 };
69 SLIST_HEAD(qop_info_list, qop_info);
70 
71 static struct qop_info_list qops = SLIST_HEAD_INITIALIZER(qops);
72 
73 static int
74 _rpc_gss_string_to_oid(const char* s, gss_OID oid)
75 {
76 	int			number_count, i, j;
77 	int			byte_count;
78 	const char		*p, *q;
79 	char			*res;
80 
81 	/*
82 	 * First figure out how many numbers in the oid, then
83 	 * calculate the compiled oid size.
84 	 */
85 	number_count = 0;
86 	for (p = s; p; p = q) {
87 		q = strchr(p, '.');
88 		if (q) q = q + 1;
89 		number_count++;
90 	}
91 
92 	/*
93 	 * The first two numbers are in the first byte and each
94 	 * subsequent number is encoded in a variable byte sequence.
95 	 */
96 	if (number_count < 2)
97 		return (EINVAL);
98 
99 	/*
100 	 * We do this in two passes. The first pass, we just figure
101 	 * out the size. Second time around, we actually encode the
102 	 * number.
103 	 */
104 	res = 0;
105 	for (i = 0; i < 2; i++) {
106 		byte_count = 0;
107 		for (p = s, j = 0; p; p = q, j++) {
108 			u_int number = 0;
109 
110 			/*
111 			 * Find the end of this number.
112 			 */
113 			q = strchr(p, '.');
114 			if (q) q = q + 1;
115 
116 			/*
117 			 * Read the number of of the string. Don't
118 			 * bother with anything except base ten.
119 			 */
120 			while (*p && *p != '.') {
121 				number = 10 * number + (*p - '0');
122 				p++;
123 			}
124 
125 			/*
126 			 * Encode the number. The first two numbers
127 			 * are packed into the first byte. Subsequent
128 			 * numbers are encoded in bytes seven bits at
129 			 * a time with the last byte having the high
130 			 * bit set.
131 			 */
132 			if (j == 0) {
133 				if (res)
134 					*res = number * 40;
135 			} else if (j == 1) {
136 				if (res) {
137 					*res += number;
138 					res++;
139 				}
140 				byte_count++;
141 			} else if (j >= 2) {
142 				/*
143 				 * The number is encoded in seven bit chunks.
144 				 */
145 				u_int t;
146 				int bytes;
147 
148 				bytes = 0;
149 				for (t = number; t; t >>= 7)
150 					bytes++;
151 				if (bytes == 0) bytes = 1;
152 				while (bytes) {
153 					if (res) {
154 						int bit = 7*(bytes-1);
155 
156 						*res = (number >> bit) & 0x7f;
157 						if (bytes != 1)
158 							*res |= 0x80;
159 						res++;
160 					}
161 					byte_count++;
162 					bytes--;
163 				}
164 			}
165 		}
166 		if (!res) {
167 			res = malloc(byte_count);
168 			if (!res)
169 				return (ENOMEM);
170 			oid->length = byte_count;
171 			oid->elements = res;
172 		}
173 	}
174 
175 	return (0);
176 }
177 
178 static void
179 _rpc_gss_load_mech(void)
180 {
181 	FILE		*fp;
182 	char		buf[256];
183 	char		*p;
184 	char		*name, *oid, *lib, *kobj;
185 	struct mech_info *info;
186 	int		count;
187 	const char	**pp;
188 
189 	if (SLIST_FIRST(&mechs))
190 		return;
191 
192 	fp = fopen(_PATH_GSS_MECH, "r");
193 	if (!fp)
194 		return;
195 
196 	count = 0;
197 	while (fgets(buf, sizeof(buf), fp)) {
198 		if (*buf == '#')
199 			continue;
200 		p = buf;
201 		name = strsep(&p, "\t\n ");
202 		if (p) while (isspace(*p)) p++;
203 		oid = strsep(&p, "\t\n ");
204 		if (p) while (isspace(*p)) p++;
205 		lib = strsep(&p, "\t\n ");
206 		if (p) while (isspace(*p)) p++;
207 		kobj = strsep(&p, "\t\n ");
208 		if (!name || !oid || !lib || !kobj)
209 			continue;
210 
211 		info = malloc(sizeof(struct mech_info));
212 		if (!info)
213 			break;
214 		if (_rpc_gss_string_to_oid(oid, &info->oid)) {
215 			free(info);
216 			continue;
217 		}
218 		info->name = strdup(name);
219 		info->qops = NULL;
220 		info->lib = strdup(lib);
221 		info->kobj = strdup(kobj);
222 		SLIST_INSERT_HEAD(&mechs, info, link);
223 		count++;
224 	}
225 	fclose(fp);
226 
227 	mech_names = malloc((count + 1) * sizeof(char*));
228 	pp = mech_names;
229 	SLIST_FOREACH(info, &mechs, link) {
230 		*pp++ = info->name;
231 	}
232 	*pp = NULL;
233 }
234 
235 static void
236 _rpc_gss_load_qop(void)
237 {
238 	FILE		*fp;
239 	char		buf[256];
240 	char		*p;
241 	char		*name, *num, *mech;
242 	struct mech_info *minfo;
243 	struct qop_info *info;
244 	int		count;
245 	const char	**mech_qops;
246 	const char	**pp;
247 
248 	if (SLIST_FIRST(&qops))
249 		return;
250 
251 	fp = fopen(_PATH_GSS_QOP, "r");
252 	if (!fp)
253 		return;
254 
255 	while (fgets(buf, sizeof(buf), fp)) {
256 		if (*buf == '#')
257 			continue;
258 		p = buf;
259 		name = strsep(&p, "\t\n ");
260 		if (p) while (isspace(*p)) p++;
261 		num = strsep(&p, "\t\n ");
262 		if (p) while (isspace(*p)) p++;
263 		mech = strsep(&p, "\t\n ");
264 		if (!name || !num || !mech)
265 			continue;
266 
267 		info = malloc(sizeof(struct qop_info));
268 		if (!info)
269 			break;
270 		info->name = strdup(name);
271 		info->qop = strtoul(name, 0, 0);
272 		info->mech = strdup(mech);
273 		SLIST_INSERT_HEAD(&qops, info, link);
274 	}
275 	fclose(fp);
276 
277 	/*
278 	 * Compile lists of qops for each mechanism.
279 	 */
280 	SLIST_FOREACH(minfo, &mechs, link) {
281 		count = 0;
282 		SLIST_FOREACH(info, &qops, link) {
283 			if (strcmp(info->mech, minfo->name) == 0)
284 				count++;
285 		}
286 		mech_qops = malloc((count + 1) * sizeof(char*));
287 		pp = mech_qops;
288 		SLIST_FOREACH(info, &qops, link) {
289 			if (strcmp(info->mech, minfo->name) == 0)
290 				*pp++ = info->name;
291 		}
292 		*pp = NULL;
293 		minfo->qops = mech_qops;
294 	}
295 }
296 
297 bool_t
298 rpc_gss_mech_to_oid(const char *mech, gss_OID *oid_ret)
299 {
300 	struct mech_info *info;
301 
302 	_rpc_gss_load_mech();
303 	SLIST_FOREACH(info, &mechs, link) {
304 		if (!strcmp(info->name, mech)) {
305 			*oid_ret = &info->oid;
306 			return (TRUE);
307 		}
308 	}
309 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
310 	return (FALSE);
311 }
312 
313 bool_t
314 rpc_gss_oid_to_mech(gss_OID oid, const char **mech_ret)
315 {
316 	struct mech_info *info;
317 
318 	_rpc_gss_load_mech();
319 	SLIST_FOREACH(info, &mechs, link) {
320 		if (oid->length == info->oid.length
321 		    && !memcmp(oid->elements, info->oid.elements,
322 			oid->length)) {
323 			*mech_ret = info->name;
324 			return (TRUE);
325 		}
326 	}
327 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
328 	return (FALSE);
329 }
330 
331 bool_t
332 rpc_gss_qop_to_num(const char *qop, const char *mech, u_int *num_ret)
333 {
334 	struct qop_info *info;
335 
336 	_rpc_gss_load_qop();
337 	SLIST_FOREACH(info, &qops, link) {
338 		if (strcmp(info->name, qop) == 0
339 		    && strcmp(info->mech, mech) == 0) {
340 			*num_ret = info->qop;
341 			return (TRUE);
342 		}
343 	}
344 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
345 	return (FALSE);
346 }
347 
348 const char *
349 _rpc_gss_num_to_qop(const char *mech, u_int num)
350 {
351 	struct qop_info *info;
352 
353 	if (num == GSS_C_QOP_DEFAULT)
354 		return "default";
355 
356 	_rpc_gss_load_qop();
357 	SLIST_FOREACH(info, &qops, link) {
358 		if (info->qop == num && strcmp(info->mech, mech) == 0) {
359 			return (info->name);
360 		}
361 	}
362 	return (NULL);
363 }
364 
365 const char **
366 rpc_gss_get_mechanisms(void)
367 {
368 
369 	_rpc_gss_load_mech();
370 	return (mech_names);
371 }
372 
373 const char **
374 rpc_gss_get_mech_info(const char *mech, rpc_gss_service_t *service)
375 {
376 	struct mech_info *info;
377 
378 	_rpc_gss_load_mech();
379 	_rpc_gss_load_qop();
380 	SLIST_FOREACH(info, &mechs, link) {
381 		if (!strcmp(mech, info->name)) {
382 			/*
383 			 * I'm not sure what to do with service
384 			 * here. The Solaris manpages are not clear on
385 			 * the subject and the OpenSolaris code just
386 			 * sets it to rpc_gss_svc_privacy
387 			 * unconditionally with a comment noting that
388 			 * it is bogus.
389 			 */
390 			*service = rpc_gss_svc_privacy;
391 			return info->qops;
392 		}
393 	}
394 
395 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
396 	return (NULL);
397 }
398 
399 bool_t
400 rpc_gss_get_versions(u_int *vers_hi, u_int *vers_lo)
401 {
402 
403 	*vers_hi = 1;
404 	*vers_lo = 1;
405 	return (TRUE);
406 }
407 
408 bool_t
409 rpc_gss_is_installed(const char *mech)
410 {
411 	struct mech_info *info;
412 
413 	_rpc_gss_load_mech();
414 	SLIST_FOREACH(info, &mechs, link)
415 		if (!strcmp(mech, info->name))
416 			return (TRUE);
417 	return (FALSE);
418 }
419 
420