xref: /titanic_44/usr/src/cmd/gss/gsscred/gsscred_file.c (revision 49335bdececa5fc091b6c63763f9176524390b5e)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include <ctype.h>
34 #include "gsscred.h"
35 
36 /*
37  *  gsscred utility
38  *  Manages mapping between a security principal name and unix uid.
39  *  Implementation file for the file based gsscred utility.
40  */
41 
42 #define	MAX_ENTRY_LEN 1024
43 static const char credFile[] = "/etc/gss/gsscred_db";
44 static const char credFileTmp[] = "/etc/gss/gsscred_db.tmp";
45 static const int expNameTokIdLen = 2;
46 static const int mechOidLenLen = 2;
47 static const int mechOidTagLen = 1;
48 
49 static int matchEntry(const char *entry, const gss_buffer_t name,
50 		const char *uid, uid_t *uidOut);
51 
52 /*
53  * file_addGssCredEntry
54  *
55  * Adds a new entry to the gsscred table.
56  * Does not check for duplicate entries.
57  */
58 int file_addGssCredEntry(const gss_buffer_t hexName, const char *uid,
59 		const char *comment, char **errDetails)
60 {
61 	FILE *fp;
62 	char tmpBuf[256];
63 
64 	if ((fp = fopen(credFile, "a")) == NULL) {
65 		if (errDetails) {
66 			(void) snprintf(tmpBuf, sizeof (tmpBuf),
67 				gettext("Unable to open gsscred file [%s]"),
68 				credFile);
69 			*errDetails = strdup(tmpBuf);
70 		}
71 		return (0);
72 	}
73 
74 	(void) fprintf(fp,
75 		    "%s\t%s\t%s\n", (char *)hexName->value, uid, comment);
76 	(void) fclose(fp);
77 	return (1);
78 }  /* *******  file_addGssCredEntry ****** */
79 
80 
81 
82 /*
83  * file_getGssCredEntry
84  *
85  * Searches the file for the file matching the name.  Since the name
86  * contains a mechanism identifier, to search for all names for a given
87  * mechanism just supply the mechanism portion in the name buffer.
88  * To search by uid only, supply a non-null value of uid.
89  */
90 int file_getGssCredEntry(const gss_buffer_t name, const char *uid,
91 		char **errDetails)
92 {
93 	FILE *fp;
94 	char entry[MAX_ENTRY_LEN+1];
95 
96 	if ((fp = fopen(credFile, "r")) == NULL) {
97 
98 		if (errDetails) {
99 			(void) snprintf(entry, sizeof (entry),
100 				gettext("Unable to open gsscred file [%s]"),
101 				credFile);
102 			*errDetails = strdup(entry);
103 		}
104 
105 		return (0);
106 	}
107 
108 	/* go through the file in sequential order */
109 	while (fgets(entry, MAX_ENTRY_LEN, fp) != NULL) {
110 		/* is there any search criteria */
111 		if (name == NULL && uid == NULL) {
112 			(void) fprintf(stdout, "%s", entry);
113 			continue;
114 		}
115 
116 		if (matchEntry(entry, name, uid, NULL))
117 			(void) fprintf(stdout, "%s", entry);
118 
119 	}	 /* while */
120 
121 	(void) fclose(fp);
122 	return (1);
123 }  /* file_getGssCredEntry */
124 
125 /*
126  * file_getGssCredUid
127  *
128  * GSS entry point for retrieving user uid information.
129  * We need to go through the entire file to ensure that
130  * the last matching entry is retrieved - this is because
131  * new entries are added to the end, and in case of
132  * duplicates we want to get the latest entry.
133  */
134 int
135 file_getGssCredUid(const gss_buffer_t expName, uid_t *uidOut)
136 {
137 	FILE *fp;
138 	char entry[MAX_ENTRY_LEN+1];
139 	int retVal = 0;
140 
141 	if ((fp = fopen(credFile, "r")) == NULL)
142 		return (0);
143 
144 	/* go through the entire file in sequential order */
145 	while (fgets(entry, MAX_ENTRY_LEN, fp) != NULL) {
146 		if (matchEntry(entry, expName, NULL, uidOut)) {
147 			retVal = 1;
148 		}
149 	} /* while */
150 
151 	(void) fclose(fp);
152 	return (retVal);
153 } /* file_getGssCredUid */
154 
155 
156 
157 /*
158  *
159  * file_deleteGssCredEntry
160  *
161  * removes entries form file that match the delete criteria
162  */
163 int file_deleteGssCredEntry(const gss_buffer_t name, const char *uid,
164 		char **errDetails)
165 {
166 	FILE *fp, *tempFp;
167 	char entry[MAX_ENTRY_LEN+1];
168 	int foundOne = 0;
169 
170 	/* are we deleting everyone? */
171 	if (name == NULL && uid == NULL) {
172 
173 		if ((fp = fopen(credFile, "w")) == NULL) {
174 
175 			if (errDetails) {
176 				(void) snprintf(entry, sizeof (entry),
177 					gettext("Unable to open gsscred"
178 						" file [%s]"),
179 					credFile);
180 				*errDetails = strdup(entry);
181 			}
182 			return (0);
183 		}
184 
185 		(void) fclose(fp);
186 		return (1);
187 	}
188 
189 	/* selective delete - might still be everyone */
190 	if ((fp = fopen(credFile, "r")) == NULL) {
191 
192 		if (errDetails) {
193 			(void) snprintf(entry, sizeof (entry),
194 				gettext("Unable to open gsscred file [%s]"),
195 				credFile);
196 			*errDetails = strdup(entry);
197 		}
198 		return (0);
199 	}
200 
201 	/* also need to open temp file */
202 	if ((tempFp = fopen(credFileTmp, "w")) == NULL) {
203 		if (errDetails) {
204 			(void) snprintf(entry, sizeof (entry),
205 				gettext("Unable to open gsscred temporary"
206 					" file [%s]"),
207 				credFileTmp);
208 			*errDetails = strdup(entry);
209 		}
210 
211 		(void) fclose(fp);
212 		return (0);
213 	}
214 
215 	/* go through all the entries sequentially removing ones that match */
216 	while (fgets(entry, MAX_ENTRY_LEN, fp) != NULL) {
217 
218 		if (!matchEntry(entry, name, uid, NULL))
219 			(void) fputs(entry, tempFp);
220 		else
221 			foundOne = 1;
222 	}
223 	(void) fclose(tempFp);
224 	(void) fclose(fp);
225 
226 	/* now make the tempfile the gsscred file */
227 	(void) rename(credFileTmp, credFile);
228 	(void) unlink(credFileTmp);
229 
230 	if (!foundOne) {
231 		*errDetails = strdup(gettext("No users found"));
232 		return (0);
233 	}
234 	return (1);
235 }  /* file_deleteGssCredEntry */
236 
237 
238 
239 /*
240  *
241  * match entry
242  *
243  * checks if the specified entry matches the supplied criteria
244  * returns 1 if yes, 0 if no
245  * uidOut value can be used to retrieve the uid from the entry
246  * when the uid string is passed in, the uidOut value is not set
247  */
248 static int matchEntry(const char *entry, const gss_buffer_t name,
249 		const char *uid, uid_t *uidOut)
250 {
251 	char fullEntry[MAX_ENTRY_LEN+1], *item, *buf;
252 	char dilims[] = "\t \n";
253 	int length, dummy;
254 	OM_uint32 minor, result;
255 	gss_buffer_desc mechOidDesc = GSS_C_EMPTY_BUFFER;
256 	gss_name_t intName;
257 	gss_buffer_desc expName;
258 	char *krb5_oid = "\052\206\110\206\367\022\001\002\002";
259 
260 	if (entry == NULL || isspace(*entry))
261 		return (0);
262 
263 	/* save the entry since strtok will chop it up */
264 	(void) strcpy(fullEntry, entry);
265 
266 	if ((item = strtok(fullEntry, dilims)) == NULL)
267 		return (0);
268 
269 	/* do wee need to search the name */
270 	if (name != NULL) {
271 		/* we can match the prefix of the string */
272 		if (strlen(item) < name->length)
273 			return (0);
274 
275 		if (memcmp(item, name->value, name->length) != 0) {
276 
277 			buf = (char *)name->value;
278 			buf += expNameTokIdLen;
279 
280 			/* skip oid length - get to der */
281 			buf += 2;
282 
283 			/* skip oid tag */
284 			buf++;
285 
286 			/* get oid length */
287 			length = get_der_length(&buf,
288 				(name->length - expNameTokIdLen
289 				- mechOidLenLen - mechOidTagLen), &dummy);
290 
291 			if (length == -1)
292 				return (0);
293 
294 			mechOidDesc.length = length;
295 
296 			/*
297 			 * check whether exported name length is within the
298 			 * boundary.
299 			 */
300 			if (name->length <
301 				(expNameTokIdLen + mechOidLenLen + length
302 					+ dummy + mechOidTagLen))
303 				return (0);
304 
305 			mechOidDesc.value = buf;
306 
307 			buf += dummy + mechOidDesc.length;
308 
309 			/*
310 			 * If the mechoid is that of Kerberos and if the
311 			 * "display" part of the exported file name starts and
312 			 * ends with a zero-valued byte, then we are dealing
313 			 * with old styled gsscred entries. We will then match
314 			 * them in the following manner:
315 			 *	- gss_import_name() the name from the file
316 			 *	- gss_export_name() the result
317 			 *	- mem_cmp() the result with the name we are
318 			 *		trying to match.
319 			 */
320 			if (mechOidDesc.length == 9 &&
321 				(memcmp(buf, krb5_oid,
322 						mechOidDesc.length) == 0) &&
323 				(*buf == '\0' && buf[length] == '\0')) {
324 				if (gss_import_name(&minor, name,
325 						GSS_C_NT_EXPORT_NAME,
326 						&intName) != GSS_S_COMPLETE)
327 					return (0);
328 				result = gss_export_name(&minor, intName,
329 								&expName);
330 				(void) gss_release_name(&minor, &intName);
331 				if (result != GSS_S_COMPLETE)
332 					return (0);
333 				result = memcmp(item, expName.value,
334 							expName.length);
335 				(void) gss_release_buffer(&minor, &expName);
336 				if (result != 0)
337 					return (0);
338 			}
339 		}
340 
341 		/* do we need to check the uid - if not then we found it */
342 		if (uid == NULL) {
343 			/* do we ned to parse out the uid ? */
344 			if (uidOut) {
345 				if ((item = strtok(NULL, dilims)) == NULL)
346 					return (0);
347 				*uidOut = atol(item);
348 			}
349 			return (1);
350 		}
351 
352 		/* continue with checking the uid */
353 	}
354 
355 	if (uid == NULL)
356 		return (1);
357 
358 	/* get the next token from the string - the uid */
359 	if ((item = strtok(NULL, dilims)) == NULL)
360 		return (0);
361 
362 	if (strcmp(item, uid) == 0)
363 		return (1);
364 
365 	return (0);
366 }  /* *******  matchEntry ****** */
367