xref: /netbsd-src/usr.bin/cap_mkdb/cap_mkdb.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /*	$NetBSD: cap_mkdb.c,v 1.27 2011/08/29 13:56:17 joerg Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 #if !defined(lint)
38 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\
39  The Regents of the University of California.  All rights reserved.");
40 #if 0
41 static char sccsid[] = "@(#)cap_mkdb.c	8.2 (Berkeley) 4/27/95";
42 #endif
43 __RCSID("$NetBSD: cap_mkdb.c,v 1.27 2011/08/29 13:56:17 joerg Exp $");
44 #endif /* not lint */
45 
46 #include <sys/param.h>
47 #include <sys/stat.h>
48 
49 #include <assert.h>
50 #include <db.h>
51 #include <err.h>
52 #include <fcntl.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include <ctype.h>
58 
59 static void	db_build(const char **);
60 static void	dounlink(void);
61 static void	usage(void) __dead;
62 static int	count_records(char **);
63 
64 static DB *capdbp;
65 static int verbose;
66 static char *capname, buf[8 * 1024];
67 
68 static HASHINFO openinfo = {
69 	4096,		/* bsize */
70 	16,		/* ffactor */
71 	2048,		/* nelem */
72 	2048 * 1024,	/* cachesize */
73 	NULL,		/* hash() */
74 	0		/* lorder */
75 };
76 
77 /*
78  * Mkcapdb creates a capability hash database for quick retrieval of capability
79  * records.  The database contains 2 types of entries: records and references
80  * marked by the first byte in the data.  A record entry contains the actual
81  * capability record whereas a reference contains the name (key) under which
82  * the correct record is stored.
83  */
84 int
85 main(int argc, char *argv[])
86 {
87 	int c, byteorder;
88 	char *p;
89 
90 	capname = NULL;
91 	byteorder = 0;
92 	while ((c = getopt(argc, argv, "bf:lv")) != -1) {
93 		switch(c) {
94 		case 'b':
95 		case 'l':
96 			if (byteorder != 0)
97 				usage();
98 			byteorder = c == 'b' ? 4321 : 1234;
99 			break;
100 		case 'f':
101 			capname = optarg;
102 			break;
103 		case 'v':
104 			verbose = 1;
105 			break;
106 		case '?':
107 		default:
108 			usage();
109 		}
110 	}
111 	argc -= optind;
112 	argv += optind;
113 
114 	if (*argv == NULL)
115 		usage();
116 
117 	/* Set byte order */
118 	openinfo.lorder = byteorder;
119 
120 	/*
121 	 * Set nelem to twice the value returned by count_record().
122 	 */
123 	openinfo.nelem = count_records(argv) << 1;
124 
125 	/*
126 	 * The database file is the first argument if no name is specified.
127 	 * Make arrangements to unlink it if exit badly.
128 	 */
129 	(void)snprintf(buf, sizeof(buf), "%s.db.tmp",
130 	    capname ? capname : *argv);
131 	if ((capname = strdup(buf)) == NULL)
132 		err(1, "strdup");
133 	if ((capdbp = dbopen(capname, O_CREAT | O_TRUNC | O_RDWR,
134 	    DEFFILEMODE, DB_HASH, &openinfo)) == NULL)
135 		err(1, "%s", buf);
136 
137 	if (atexit(dounlink))
138 		err(1, "atexit");
139 
140 	db_build((void *)argv);
141 
142 	if (capdbp->close(capdbp) < 0)
143 		err(1, "%s", capname);
144 	assert((p = strrchr(buf, '.')) != NULL);
145 	*p = '\0';
146 	if (rename(capname, buf) == -1)
147 		err(1, "rename");
148 	free(capname);
149 	capname = NULL;
150 	return 0;
151 }
152 
153 static void
154 dounlink(void)
155 {
156 	if (capname != NULL)
157 		(void)unlink(capname);
158 }
159 
160 /*
161  * Any changes to these definitions should be made also in the getcap(3)
162  * library routines.
163  */
164 #define RECOK	(char)0
165 #define TCERR	(char)1
166 #define SHADOW	(char)2
167 
168 /*
169  * Db_build() builds the name and capabilty databases according to the
170  * details above.
171  */
172 static void
173 db_build(const char **ifiles)
174 {
175 	DBT key, data;
176 	recno_t reccnt;
177 	size_t len, bplen;
178 	int st;
179 	char *bp, *p, *t, *n;
180 
181 	data.data = NULL;
182 	key.data = NULL;
183 	for (reccnt = 0, bplen = 0; (st = cgetnext(&bp, ifiles)) > 0; free(bp)){
184 
185 		/*
186 		 * Allocate enough memory to store record, terminating
187 		 * NULL and one extra byte.
188 		 */
189 		len = strlen(bp);
190 		if (bplen <= len + 2) {
191 			if ((n = realloc(data.data,
192 			    bplen + MAX(256, len + 2))) == NULL)
193 				err(1, "realloc");
194 			data.data = n;
195 			bplen += MAX(256, len + 2);
196 		}
197 
198 		/* Find the end of the name field. */
199 		if ((p = strchr(bp, ':')) == NULL) {
200 			warnx("no name field: %.*s", (int)(MIN(len, 20)), bp);
201 			continue;
202 		}
203 
204 		/* First byte of stored record indicates status. */
205 		switch(st) {
206 		case 1:
207 			((char *)(data.data))[0] = RECOK;
208 			break;
209 		case 2:
210 			((char *)(data.data))[0] = TCERR;
211 			warnx("Record not tc expanded: %.*s", (int)(p - bp),bp);
212 			break;
213 		}
214 
215 		/* Create the stored record. */
216 		(void)memmove(&((u_char *)(data.data))[1], bp, len + 1);
217 		data.size = len + 2;
218 
219 		/* Store the record under the name field. */
220 		key.data = bp;
221 		key.size = p - bp;
222 
223 		switch(capdbp->put(capdbp, &key, &data, R_NOOVERWRITE)) {
224 		case -1:
225 			err(1, "put");
226 			/* NOTREACHED */
227 		case 1:
228 			warnx("ignored duplicate: %.*s",
229 			    (int)key.size, (char *)key.data);
230 			continue;
231 		}
232 		++reccnt;
233 
234 		/* If only one name, ignore the rest. */
235 		if ((p = strchr(bp, '|')) == NULL)
236 			continue;
237 
238 		/* The rest of the names reference the entire name. */
239 		((char *)(data.data))[0] = SHADOW;
240 		(void)memmove(&((u_char *)(data.data))[1], key.data, key.size);
241 		data.size = key.size + 1;
242 
243 		/* Store references for other names. */
244 		for (p = t = bp;; ++p) {
245 			if (p > t && (*p == ':' || *p == '|')) {
246 				key.size = p - t;
247 				key.data = t;
248 				switch(capdbp->put(capdbp,
249 				    &key, &data, R_NOOVERWRITE)) {
250 				case -1:
251 					err(1, "put");
252 					/* NOTREACHED */
253 				case 1:
254 					warnx("ignored duplicate: %.*s",
255 					    (int)key.size, (char *)key.data);
256 				}
257 				t = p + 1;
258 			}
259 			if (*p == ':')
260 				break;
261 		}
262 	}
263 
264 	switch(st) {
265 	case -1:
266 		err(1, "file argument");
267 		/* NOTREACHED */
268 	case -2:
269 		errx(1, "potential reference loop detected");
270 		/* NOTREACHED */
271 	}
272 
273 	if (verbose)
274 		(void)printf("cap_mkdb: %d capability records\n", reccnt);
275 }
276 
277 static void
278 usage(void)
279 {
280 	(void)fprintf(stderr,
281 	    "Usage: %s [-b|-l] [-v] [-f outfile] file1 [file2 ...]\n",
282 	    getprogname());
283 	exit(1);
284 }
285 
286 /*
287  * Count number of records in input files. This does not need
288  * to be really accurate (the result is used only as a hint).
289  * It seems to match number of records should a cgetnext() be used, though.
290  */
291 static int
292 count_records(char **list)
293 {
294 	FILE *fp;
295 	char *line;
296 	size_t len;
297 	int nelem, slash;
298 
299 	/* scan input files and count individual records */
300 	for(nelem = 0, slash = 0; *list && (fp = fopen(*list++, "r")); ) {
301 		while((line = fgetln(fp, &len)) != NULL) {
302 			if (len < 2)
303 				continue;
304 			if (!isspace((unsigned char) *line) && *line != ':'
305 				&& *line != '#' && !slash)
306 				nelem++;
307 
308 			slash = (line[len - 2] == '\\');
309 		}
310 		(void)fclose(fp);
311 	}
312 
313 	if (nelem == 0) {
314 		/* no records found; pass default size hint */
315 		nelem = 1;
316 	} else if (!powerof2(nelem)) {
317 		/* set nelem to nearest bigger power-of-two number */
318 		int bt = 1;
319 		while(bt < nelem) bt <<= 1;
320 		nelem = bt;
321 	}
322 
323 	return nelem;
324 }
325