xref: /openbsd/usr.sbin/kvm_mkdb/kvm_mkdb.c (revision 5c94ac0a)
1 /*	$OpenBSD: kvm_mkdb.c,v 1.22 2015/10/13 15:43:19 deraadt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990, 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/stat.h>
33 #include <sys/types.h>
34 #include <sys/time.h>
35 #include <sys/resource.h>
36 
37 #include <db.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <libgen.h>
42 #include <paths.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47 #include <grp.h>
48 
49 #include "extern.h"
50 
51 void usage(void);
52 int kvm_mkdb(int, const char *, char *, char *, int);
53 
54 HASHINFO openinfo = {
55 	4096,		/* bsize */
56 	128,		/* ffactor */
57 	1024,		/* nelem */
58 	2048 * 1024,	/* cachesize */
59 	NULL,		/* hash() */
60 	0		/* lorder */
61 };
62 
63 int
64 main(int argc, char *argv[])
65 {
66 	struct rlimit rl;
67 	int fd, rval, ch, verbose = 0;
68 	char *nlistpath, *nlistname;
69 	char dbdir[PATH_MAX];
70 
71 	/* Increase our data size to the max if we can. */
72 	if (getrlimit(RLIMIT_DATA, &rl) == 0) {
73 		rl.rlim_cur = rl.rlim_max;
74 		if (setrlimit(RLIMIT_DATA, &rl) < 0)
75 			warn("can't set rlimit data size");
76 	}
77 
78 	/* getpwnam() and fchown() later */
79 	if (pledge("stdio rpath wpath cpath getpw fattr proc", NULL) == -1)
80 		err(1, "pledge");
81 
82 	strlcpy(dbdir, _PATH_VARDB, sizeof(dbdir));
83 	while ((ch = getopt(argc, argv, "vo:")) != -1)
84 		switch (ch) {
85 		case 'v':
86 			verbose = 1;
87 			break;
88 		case 'o':
89 			rval = strlcpy(dbdir, optarg, sizeof(dbdir));
90 			if (rval == 0 || rval + 1 >= sizeof(dbdir))
91 				errx(1, "Invalid directory");
92 			/* Make sure there is a '/' at the end of the path */
93 			if (dbdir[strlen(dbdir) - 1] != '/')
94 				strlcat(dbdir, "/", sizeof(dbdir));
95 			break;
96 		default:
97 			usage();
98 		}
99 	argc -= optind;
100 	argv += optind;
101 
102 	if (argc > 1)
103 		usage();
104 
105 	/* If no kernel specified use _PATH_KSYMS and fall back to _PATH_UNIX */
106 	if (argc > 0) {
107 		nlistpath = argv[0];
108 		nlistname = basename(nlistpath);
109 		if ((fd = open(nlistpath, O_RDONLY, 0)) == -1)
110 			err(1, "can't open %s", nlistpath);
111 		rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname, verbose);
112 	} else {
113 		nlistname = basename(_PATH_UNIX);
114 		if ((fd = open((nlistpath = _PATH_KSYMS), O_RDONLY, 0)) == -1 ||
115 		    (rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname,
116 		    verbose)) != 0) {
117 			if (fd == -1)
118 				warnx("can't open %s", _PATH_KSYMS);
119 			else
120 				warnx("will try again using %s instead", _PATH_UNIX);
121 			if ((fd = open((nlistpath = _PATH_UNIX), O_RDONLY, 0)) == -1)
122 				err(1, "can't open %s", nlistpath);
123 			rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname,
124 			    verbose);
125 		}
126 	}
127 	exit(rval);
128 }
129 
130 int
131 kvm_mkdb(int fd, const char *dbdir, char *nlistpath, char *nlistname,
132     int verbose)
133 {
134 	DB *db;
135 	char dbtemp[PATH_MAX], dbname[PATH_MAX];
136 	int r;
137 	struct group *gr;
138 
139 	r = snprintf(dbtemp, sizeof(dbtemp), "%skvm_%s.tmp",
140 	    dbdir, nlistname);
141 	if (r < 0 || r >= sizeof(dbtemp)) {
142 		warnx("Directory name too long");
143 		return (1);
144 	}
145 	r = snprintf(dbname, sizeof(dbname), "%skvm_%s.db",
146 	    dbdir, nlistname);
147 	if (r < 0 || r >= sizeof(dbtemp)) {
148 		warnx("Directory name too long");
149 		return (1);
150 	}
151 
152 	/* If the existing db file matches the currently running kernel, exit */
153 	if (testdb(dbname)) {
154 		if (verbose)
155 			warnx("%s already up to date", dbname);
156 		return(0);
157 	} else if (verbose)
158 		warnx("rebuilding %s", dbname);
159 
160 	(void)umask(0);
161 	db = dbopen(dbtemp, O_CREAT | O_EXLOCK | O_TRUNC | O_RDWR,
162 	    S_IRUSR | S_IWUSR | S_IRGRP, DB_HASH, &openinfo);
163 	if (db == NULL) {
164 		warn("can't dbopen %s", dbtemp);
165 		return(1);
166 	}
167 
168 	if ((gr = getgrnam("kmem")) == NULL) {
169 		warn("can't find kmem group");
170 	} else if (fchown(db->fd(db), -1, gr->gr_gid)) {
171 		warn("can't chown %s", dbtemp);
172 		(void)unlink(dbtemp);
173 		return(1);
174 	}
175 
176 	/* rename() later */
177 	if (pledge("stdio cpath", NULL) == -1)
178 		err(1, "pledge");
179 
180 	if (create_knlist(nlistpath, fd, db) != 0) {
181 		warn("cannot determine executable type of %s", nlistpath);
182 		(void)unlink(dbtemp);
183 		return(1);
184 	}
185 	if (db->close(db)) {
186 		warn("can't dbclose %s", dbtemp);
187 		(void)unlink(dbtemp);
188 		return(1);
189 	}
190 
191 	if (rename(dbtemp, dbname)) {
192 		warn("rename %s to %s", dbtemp, dbname);
193 		(void)unlink(dbtemp);
194 		return(1);
195 	}
196 
197 	return(0);
198 }
199 
200 void
201 usage(void)
202 {
203 	(void)fprintf(stderr, "usage: kvm_mkdb [-v] [-o directory] [file]\n");
204 	exit(1);
205 }
206