xref: /freebsd/lib/librpcsec_gss/rpcsec_gss_conf.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
29 #include <ctype.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <stdlib.h>
33 #include <errno.h>
34 #include <sys/queue.h>
35 #include <rpc/rpc.h>
36 #include <rpc/rpcsec_gss.h>
37 
38 #include "rpcsec_gss_int.h"
39 
40 #ifndef _PATH_GSS_MECH
41 #define _PATH_GSS_MECH	"/etc/gss/mech"
42 #endif
43 
44 #ifndef _PATH_GSS_QOP
45 #define _PATH_GSS_QOP	"/etc/gss/qop"
46 #endif
47 
48 struct mech_info {
49 	SLIST_ENTRY(mech_info) link;
50 	char		*name;
51 	gss_OID_desc	oid;
52 	const char	**qops;
53 	char		*lib;
54 	char		*kobj;
55 };
56 SLIST_HEAD(mech_info_list, mech_info);
57 
58 static struct mech_info_list mechs = SLIST_HEAD_INITIALIZER(mechs);
59 static const char **mech_names;
60 
61 struct qop_info {
62 	SLIST_ENTRY(qop_info) link;
63 	char		*name;
64 	char*		mech;
65 	u_int		qop;
66 };
67 SLIST_HEAD(qop_info_list, qop_info);
68 
69 static struct qop_info_list qops = SLIST_HEAD_INITIALIZER(qops);
70 
71 static int
72 _rpc_gss_string_to_oid(const char* s, gss_OID oid)
73 {
74 	int			number_count, i, j;
75 	int			byte_count;
76 	const char		*p, *q;
77 	char			*res;
78 
79 	/*
80 	 * First figure out how many numbers in the oid, then
81 	 * calculate the compiled oid size.
82 	 */
83 	number_count = 0;
84 	for (p = s; p; p = q) {
85 		q = strchr(p, '.');
86 		if (q) q = q + 1;
87 		number_count++;
88 	}
89 
90 	/*
91 	 * The first two numbers are in the first byte and each
92 	 * subsequent number is encoded in a variable byte sequence.
93 	 */
94 	if (number_count < 2)
95 		return (EINVAL);
96 
97 	/*
98 	 * We do this in two passes. The first pass, we just figure
99 	 * out the size. Second time around, we actually encode the
100 	 * number.
101 	 */
102 	res = 0;
103 	for (i = 0; i < 2; i++) {
104 		byte_count = 0;
105 		for (p = s, j = 0; p; p = q, j++) {
106 			u_int number = 0;
107 
108 			/*
109 			 * Find the end of this number.
110 			 */
111 			q = strchr(p, '.');
112 			if (q) q = q + 1;
113 
114 			/*
115 			 * Read the number of of the string. Don't
116 			 * bother with anything except base ten.
117 			 */
118 			while (*p && *p != '.') {
119 				number = 10 * number + (*p - '0');
120 				p++;
121 			}
122 
123 			/*
124 			 * Encode the number. The first two numbers
125 			 * are packed into the first byte. Subsequent
126 			 * numbers are encoded in bytes seven bits at
127 			 * a time with the last byte having the high
128 			 * bit set.
129 			 */
130 			if (j == 0) {
131 				if (res)
132 					*res = number * 40;
133 			} else if (j == 1) {
134 				if (res) {
135 					*res += number;
136 					res++;
137 				}
138 				byte_count++;
139 			} else if (j >= 2) {
140 				/*
141 				 * The number is encoded in seven bit chunks.
142 				 */
143 				u_int t;
144 				int bytes;
145 
146 				bytes = 0;
147 				for (t = number; t; t >>= 7)
148 					bytes++;
149 				if (bytes == 0) bytes = 1;
150 				while (bytes) {
151 					if (res) {
152 						int bit = 7*(bytes-1);
153 
154 						*res = (number >> bit) & 0x7f;
155 						if (bytes != 1)
156 							*res |= 0x80;
157 						res++;
158 					}
159 					byte_count++;
160 					bytes--;
161 				}
162 			}
163 		}
164 		if (!res) {
165 			res = malloc(byte_count);
166 			if (!res)
167 				return (ENOMEM);
168 			oid->length = byte_count;
169 			oid->elements = res;
170 		}
171 	}
172 
173 	return (0);
174 }
175 
176 static void
177 _rpc_gss_load_mech(void)
178 {
179 	FILE		*fp;
180 	char		buf[256];
181 	char		*p;
182 	char		*name, *oid, *lib, *kobj;
183 	struct mech_info *info;
184 	int		count;
185 	const char	**pp;
186 
187 	if (SLIST_FIRST(&mechs))
188 		return;
189 
190 	fp = fopen(_PATH_GSS_MECH, "r");
191 	if (!fp)
192 		return;
193 
194 	count = 0;
195 	while (fgets(buf, sizeof(buf), fp)) {
196 		if (*buf == '#')
197 			continue;
198 		p = buf;
199 		name = strsep(&p, "\t\n ");
200 		if (p) while (isspace(*p)) p++;
201 		oid = strsep(&p, "\t\n ");
202 		if (p) while (isspace(*p)) p++;
203 		lib = strsep(&p, "\t\n ");
204 		if (p) while (isspace(*p)) p++;
205 		kobj = strsep(&p, "\t\n ");
206 		if (!name || !oid || !lib || !kobj)
207 			continue;
208 
209 		info = malloc(sizeof(struct mech_info));
210 		if (!info)
211 			break;
212 		if (_rpc_gss_string_to_oid(oid, &info->oid)) {
213 			free(info);
214 			continue;
215 		}
216 		info->name = strdup(name);
217 		info->qops = NULL;
218 		info->lib = strdup(lib);
219 		info->kobj = strdup(kobj);
220 		SLIST_INSERT_HEAD(&mechs, info, link);
221 		count++;
222 	}
223 	fclose(fp);
224 
225 	mech_names = malloc((count + 1) * sizeof(char*));
226 	pp = mech_names;
227 	SLIST_FOREACH(info, &mechs, link) {
228 		*pp++ = info->name;
229 	}
230 	*pp = NULL;
231 }
232 
233 static void
234 _rpc_gss_load_qop(void)
235 {
236 	FILE		*fp;
237 	char		buf[256];
238 	char		*p;
239 	char		*name, *num, *mech;
240 	struct mech_info *minfo;
241 	struct qop_info *info;
242 	int		count;
243 	const char	**mech_qops;
244 	const char	**pp;
245 
246 	if (SLIST_FIRST(&qops))
247 		return;
248 
249 	fp = fopen(_PATH_GSS_QOP, "r");
250 	if (!fp)
251 		return;
252 
253 	while (fgets(buf, sizeof(buf), fp)) {
254 		if (*buf == '#')
255 			continue;
256 		p = buf;
257 		name = strsep(&p, "\t\n ");
258 		if (p) while (isspace(*p)) p++;
259 		num = strsep(&p, "\t\n ");
260 		if (p) while (isspace(*p)) p++;
261 		mech = strsep(&p, "\t\n ");
262 		if (!name || !num || !mech)
263 			continue;
264 
265 		info = malloc(sizeof(struct qop_info));
266 		if (!info)
267 			break;
268 		info->name = strdup(name);
269 		info->qop = strtoul(name, 0, 0);
270 		info->mech = strdup(mech);
271 		SLIST_INSERT_HEAD(&qops, info, link);
272 	}
273 	fclose(fp);
274 
275 	/*
276 	 * Compile lists of qops for each mechanism.
277 	 */
278 	SLIST_FOREACH(minfo, &mechs, link) {
279 		count = 0;
280 		SLIST_FOREACH(info, &qops, link) {
281 			if (strcmp(info->mech, minfo->name) == 0)
282 				count++;
283 		}
284 		mech_qops = malloc((count + 1) * sizeof(char*));
285 		pp = mech_qops;
286 		SLIST_FOREACH(info, &qops, link) {
287 			if (strcmp(info->mech, minfo->name) == 0)
288 				*pp++ = info->name;
289 		}
290 		*pp = NULL;
291 		minfo->qops = mech_qops;
292 	}
293 }
294 
295 bool_t
296 rpc_gss_mech_to_oid(const char *mech, gss_OID *oid_ret)
297 {
298 	struct mech_info *info;
299 
300 	_rpc_gss_load_mech();
301 	SLIST_FOREACH(info, &mechs, link) {
302 		if (!strcmp(info->name, mech)) {
303 			*oid_ret = &info->oid;
304 			return (TRUE);
305 		}
306 	}
307 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
308 	return (FALSE);
309 }
310 
311 bool_t
312 rpc_gss_oid_to_mech(gss_OID oid, const char **mech_ret)
313 {
314 	struct mech_info *info;
315 
316 	_rpc_gss_load_mech();
317 	SLIST_FOREACH(info, &mechs, link) {
318 		if (oid->length == info->oid.length
319 		    && !memcmp(oid->elements, info->oid.elements,
320 			oid->length)) {
321 			*mech_ret = info->name;
322 			return (TRUE);
323 		}
324 	}
325 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
326 	return (FALSE);
327 }
328 
329 bool_t
330 rpc_gss_qop_to_num(const char *qop, const char *mech, u_int *num_ret)
331 {
332 	struct qop_info *info;
333 
334 	_rpc_gss_load_qop();
335 	SLIST_FOREACH(info, &qops, link) {
336 		if (strcmp(info->name, qop) == 0
337 		    && strcmp(info->mech, mech) == 0) {
338 			*num_ret = info->qop;
339 			return (TRUE);
340 		}
341 	}
342 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
343 	return (FALSE);
344 }
345 
346 const char *
347 _rpc_gss_num_to_qop(const char *mech, u_int num)
348 {
349 	struct qop_info *info;
350 
351 	if (num == GSS_C_QOP_DEFAULT)
352 		return "default";
353 
354 	_rpc_gss_load_qop();
355 	SLIST_FOREACH(info, &qops, link) {
356 		if (info->qop == num && strcmp(info->mech, mech) == 0) {
357 			return (info->name);
358 		}
359 	}
360 	return (NULL);
361 }
362 
363 const char **
364 rpc_gss_get_mechanisms(void)
365 {
366 
367 	_rpc_gss_load_mech();
368 	return (mech_names);
369 }
370 
371 const char **
372 rpc_gss_get_mech_info(const char *mech, rpc_gss_service_t *service)
373 {
374 	struct mech_info *info;
375 
376 	_rpc_gss_load_mech();
377 	_rpc_gss_load_qop();
378 	SLIST_FOREACH(info, &mechs, link) {
379 		if (!strcmp(mech, info->name)) {
380 			/*
381 			 * I'm not sure what to do with service
382 			 * here. The Solaris manpages are not clear on
383 			 * the subject and the OpenSolaris code just
384 			 * sets it to rpc_gss_svc_privacy
385 			 * unconditionally with a comment noting that
386 			 * it is bogus.
387 			 */
388 			*service = rpc_gss_svc_privacy;
389 			return info->qops;
390 		}
391 	}
392 
393 	_rpc_gss_set_error(RPC_GSS_ER_SYSTEMERROR, ENOENT);
394 	return (NULL);
395 }
396 
397 bool_t
398 rpc_gss_get_versions(u_int *vers_hi, u_int *vers_lo)
399 {
400 
401 	*vers_hi = 1;
402 	*vers_lo = 1;
403 	return (TRUE);
404 }
405 
406 bool_t
407 rpc_gss_is_installed(const char *mech)
408 {
409 	struct mech_info *info;
410 
411 	_rpc_gss_load_mech();
412 	SLIST_FOREACH(info, &mechs, link)
413 		if (!strcmp(mech, info->name))
414 			return (TRUE);
415 	return (FALSE);
416 }
417 
418