xref: /freebsd/usr.bin/cap_mkdb/cap_mkdb.c (revision f126890a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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 #include <sys/param.h>
33 #include <sys/stat.h>
34 
35 #include <db.h>
36 #include <err.h>
37 #include <fcntl.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 static void	 db_build(char **);
44 static void	 dounlink(void);
45 static void	 usage(void);
46 
47 static DB	*capdbp;
48 static int	 verbose;
49 static char	*capname, buf[8 * 1024];
50 
51 static HASHINFO openinfo = {
52 	4096,		/* bsize */
53 	0,		/* ffactor */
54 	0,		/* nelem */
55 	0,		/* cachesize */
56 	NULL,		/* hash() */
57 	0		/* lorder */
58 };
59 
60 /*
61  * Mkcapdb creates a capability hash database for quick retrieval of capability
62  * records.  The database contains 2 types of entries: records and references
63  * marked by the first byte in the data.  A record entry contains the actual
64  * capability record whereas a reference contains the name (key) under which
65  * the correct record is stored.
66  */
67 int
68 main(int argc, char *argv[])
69 {
70 	int byteorder, c;
71 
72 	capname = NULL;
73 	byteorder = 0;
74 	while ((c = getopt(argc, argv, "bf:lv")) != -1) {
75 		switch(c) {
76 		case 'b':
77 		case 'l':
78 			if (byteorder != 0)
79 				usage();
80 			byteorder = c == 'b' ? 4321 : 1234;
81 			break;
82 		case 'f':
83 			capname = optarg;
84 			break;
85 		case 'v':
86 			verbose = 1;
87 			break;
88 		case '?':
89 		default:
90 			usage();
91 		}
92 	}
93 	argc -= optind;
94 	argv += optind;
95 
96 	if (*argv == NULL)
97 		usage();
98 
99 	/* Set byte order. */
100 	openinfo.lorder = byteorder;
101 
102 	/*
103 	 * The database file is the first argument if no name is specified.
104 	 * Make arrangements to unlink it if exit badly.
105 	 */
106 	(void)snprintf(buf, sizeof(buf), "%s.db", capname ? capname : *argv);
107 	if ((capname = strdup(buf)) == NULL)
108 		errx(1, "strdup failed");
109 	if ((capdbp = dbopen(capname, O_CREAT | O_TRUNC | O_RDWR,
110 	    DEFFILEMODE, DB_HASH, &openinfo)) == NULL)
111 		err(1, "%s", buf);
112 
113 	if (atexit(dounlink))
114 		err(1, "atexit");
115 
116 	db_build(argv);
117 
118 	if (capdbp->close(capdbp) < 0)
119 		err(1, "%s", capname);
120 	capname = NULL;
121 	exit(0);
122 }
123 
124 static void
125 dounlink(void)
126 {
127 	if (capname != NULL)
128 		(void)unlink(capname);
129 }
130 
131 /*
132  * Any changes to these definitions should be made also in the getcap(3)
133  * library routines.
134  */
135 #define RECOK	(char)0
136 #define TCERR	(char)1
137 #define SHADOW	(char)2
138 
139 /*
140  * Db_build() builds the name and capability databases according to the
141  * details above.
142  */
143 static void
144 db_build(char **ifiles)
145 {
146 	DBT key, data;
147 	recno_t reccnt;
148 	size_t len, bplen;
149 	int st;
150 	char *bp, *p, *t;
151 
152 	data.data = NULL;
153 	key.data = NULL;
154 	for (reccnt = 0, bplen = 0; (st = cgetnext(&bp, ifiles)) > 0;) {
155 
156 		/*
157 		 * Allocate enough memory to store record, terminating
158 		 * NULL and one extra byte.
159 		 */
160 		len = strlen(bp);
161 		if (bplen <= len + 2) {
162 			bplen += MAX(256, len + 2);
163 			if ((data.data = realloc(data.data, bplen)) == NULL)
164 				errx(1, "malloc failed");
165 		}
166 
167 		/* Find the end of the name field. */
168 		if ((p = strchr(bp, ':')) == NULL) {
169 			warnx("no name field: %.*s", (int)MIN(len, 20), bp);
170 			continue;
171 		}
172 
173 		/* First byte of stored record indicates status. */
174 		switch(st) {
175 		case 1:
176 			((char *)(data.data))[0] = RECOK;
177 			break;
178 		case 2:
179 			((char *)(data.data))[0] = TCERR;
180 			warnx("record not tc expanded: %.*s", (int)(p - bp),
181 			    bp);
182 			break;
183 		}
184 
185 		/* Create the stored record. */
186 		memmove(&((u_char *)(data.data))[1], bp, len + 1);
187 		data.size = len + 2;
188 
189 		/* Store the record under the name field. */
190 		key.data = bp;
191 		key.size = p - bp;
192 
193 		switch(capdbp->put(capdbp, &key, &data, R_NOOVERWRITE)) {
194 		case -1:
195 			err(1, "put");
196 			/* NOTREACHED */
197 		case 1:
198 			warnx("ignored duplicate: %.*s",
199 			    (int)key.size, (char *)key.data);
200 			continue;
201 		}
202 		++reccnt;
203 
204 		/* If only one name, ignore the rest. */
205 		*p = '\0';
206 		if (strchr(bp, '|') == NULL)
207 			continue;
208 		*p = ':';
209 
210 		/* The rest of the names reference the entire name. */
211 		((char *)(data.data))[0] = SHADOW;
212 		memmove(&((u_char *)(data.data))[1], key.data, key.size);
213 		data.size = key.size + 1;
214 
215 		/* Store references for other names. */
216 		for (p = t = bp;; ++p) {
217 			if (p > t && (*p == ':' || *p == '|')) {
218 				key.size = p - t;
219 				key.data = t;
220 				switch(capdbp->put(capdbp,
221 				    &key, &data, R_NOOVERWRITE)) {
222 				case -1:
223 					err(1, "put");
224 					/* NOTREACHED */
225 				case 1:
226 					warnx("ignored duplicate: %.*s",
227 					    (int)key.size, (char *)key.data);
228 				}
229 				t = p + 1;
230 			}
231 			if (*p == ':')
232 				break;
233 		}
234 	}
235 
236 	switch(st) {
237 	case -1:
238 		err(1, "file argument");
239 		/* NOTREACHED */
240 	case -2:
241 		errx(1, "potential reference loop detected");
242 		/* NOTREACHED */
243 	}
244 
245 	if (verbose)
246 		(void)printf("cap_mkdb: %d capability records\n", reccnt);
247 }
248 
249 static void
250 usage(void)
251 {
252 	(void)fprintf(stderr,
253 	    "usage: cap_mkdb [-b | -l] [-v] [-f outfile] file ...\n");
254 	exit(1);
255 }
256