1 /* $OpenBSD: testdb.c,v 1.8 2009/10/27 23:59:51 deraadt 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 #include <sys/param.h> 33 #include <sys/sysctl.h> 34 35 #include <db.h> 36 #include <fcntl.h> 37 #include <kvm.h> 38 #include <limits.h> 39 #include <paths.h> 40 #include <stdio.h> 41 #include <string.h> 42 #include <unistd.h> 43 44 #include "extern.h" 45 46 /* Return true if the db file is valid, else false */ 47 int 48 testdb(char *dbname) 49 { 50 DBT rec; 51 DB *db = NULL; 52 size_t kversionlen; 53 char kversion[LINE_MAX]; 54 int mib[2], ret = 0; 55 56 /* Read version string of running kernel */ 57 mib[0] = CTL_KERN; 58 mib[1] = KERN_VERSION; 59 kversionlen = sizeof(kversion); 60 if (sysctl(mib, 2, kversion, &kversionlen, NULL, 0) < 0) 61 goto close; 62 63 /* Read the version out of the database */ 64 if ((db = dbopen(dbname, O_RDONLY, 0, DB_HASH, NULL)) == NULL) 65 goto close; 66 rec.data = VRS_KEY; 67 rec.size = sizeof(VRS_KEY) - 1; 68 if ((db->get)(db, &rec, &rec, 0)) 69 goto close; 70 if (rec.data == NULL || rec.size > kversionlen) 71 goto close; 72 73 /* If they match, we win */ 74 ret = memcmp(kversion, rec.data, rec.size) == 0; 75 76 close: 77 if (db) 78 (void)(db->close)(db); 79 return (ret); 80 } 81