1 /* $OpenBSD: kvm_mkdb.c,v 1.28 2016/04/25 16:03:57 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 __dead void usage(void); 52 int kvm_mkdb(int, const char *, char *, char *, gid_t, 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 struct group *gr; 68 gid_t kvm_gid = -1; 69 int fd, rval, ch, verbose = 0; 70 char *nlistpath, *nlistname; 71 char dbdir[PATH_MAX]; 72 73 if (pledge("stdio rpath wpath cpath fattr getpw flock id", NULL) == -1) 74 err(1, "pledge"); 75 76 /* Try to use the kmem group to be able to fchown() in kvm_mkdb(). */ 77 if ((gr = getgrnam("kmem")) == NULL) { 78 warn("can't find kmem group"); 79 } else { 80 kvm_gid = gr->gr_gid; 81 if (setresgid(kvm_gid, kvm_gid, kvm_gid) == -1) 82 err(1, "setegid"); 83 } 84 85 /* Increase our data size to the max if we can. */ 86 if (getrlimit(RLIMIT_DATA, &rl) == 0) { 87 rl.rlim_cur = rl.rlim_max; 88 if (setrlimit(RLIMIT_DATA, &rl) < 0) 89 warn("can't set rlimit data size"); 90 } 91 92 if (pledge("stdio rpath wpath cpath fattr flock", NULL) == -1) 93 err(1, "pledge"); 94 95 strlcpy(dbdir, _PATH_VARDB, sizeof(dbdir)); 96 while ((ch = getopt(argc, argv, "vo:")) != -1) 97 switch (ch) { 98 case 'v': 99 verbose = 1; 100 break; 101 case 'o': 102 rval = strlcpy(dbdir, optarg, sizeof(dbdir)); 103 if (rval == 0 || rval + 1 >= sizeof(dbdir)) 104 errx(1, "Invalid directory"); 105 /* Make sure there is a '/' at the end of the path */ 106 if (dbdir[strlen(dbdir) - 1] != '/') 107 strlcat(dbdir, "/", sizeof(dbdir)); 108 break; 109 default: 110 usage(); 111 } 112 argc -= optind; 113 argv += optind; 114 115 if (argc > 1) 116 usage(); 117 118 /* If no kernel specified use _PATH_KSYMS and fall back to _PATH_UNIX */ 119 if (argc > 0) { 120 nlistpath = argv[0]; 121 nlistname = basename(nlistpath); 122 if ((fd = open(nlistpath, O_RDONLY, 0)) == -1) 123 err(1, "can't open %s", nlistpath); 124 rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname, kvm_gid, 125 verbose); 126 } else { 127 nlistname = basename(_PATH_UNIX); 128 if ((fd = open((nlistpath = _PATH_KSYMS), O_RDONLY, 0)) == -1 || 129 (rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname, kvm_gid, 130 verbose)) != 0) { 131 if (fd == -1) 132 warnx("can't open %s", _PATH_KSYMS); 133 else 134 warnx("will try again using %s instead", _PATH_UNIX); 135 if ((fd = open((nlistpath = _PATH_UNIX), O_RDONLY, 0)) == -1) 136 err(1, "can't open %s", nlistpath); 137 rval = kvm_mkdb(fd, dbdir, nlistpath, nlistname, 138 kvm_gid, verbose); 139 } 140 } 141 exit(rval); 142 } 143 144 int 145 kvm_mkdb(int fd, const char *dbdir, char *nlistpath, char *nlistname, gid_t gid, 146 int verbose) 147 { 148 DB *db; 149 char dbtemp[PATH_MAX], dbname[PATH_MAX]; 150 int r; 151 152 r = snprintf(dbtemp, sizeof(dbtemp), "%skvm_%s.tmp", 153 dbdir, nlistname); 154 if (r < 0 || r >= sizeof(dbtemp)) { 155 warnx("Directory name too long"); 156 return (1); 157 } 158 r = snprintf(dbname, sizeof(dbname), "%skvm_%s.db", 159 dbdir, nlistname); 160 if (r < 0 || r >= sizeof(dbtemp)) { 161 warnx("Directory name too long"); 162 return (1); 163 } 164 165 /* If the existing db file matches the currently running kernel, exit */ 166 if (testdb(dbname)) { 167 if (verbose) 168 warnx("%s already up to date", dbname); 169 return(0); 170 } else if (verbose) 171 warnx("rebuilding %s", dbname); 172 173 (void)umask(0); 174 db = dbopen(dbtemp, O_CREAT | O_EXLOCK | O_TRUNC | O_RDWR, 175 S_IRUSR | S_IWUSR | S_IRGRP, DB_HASH, &openinfo); 176 if (db == NULL) { 177 warn("can't dbopen %s", dbtemp); 178 return(1); 179 } 180 181 if (gid != -1 && fchown(db->fd(db), -1, gid) == -1) { 182 warn("can't chown %s", dbtemp); 183 (void)unlink(dbtemp); 184 return(1); 185 } 186 187 if (create_knlist(nlistpath, fd, db) != 0) { 188 warn("cannot determine executable type of %s", nlistpath); 189 (void)unlink(dbtemp); 190 return(1); 191 } 192 if (db->close(db)) { 193 warn("can't dbclose %s", dbtemp); 194 (void)unlink(dbtemp); 195 return(1); 196 } 197 198 if (rename(dbtemp, dbname)) { 199 warn("rename %s to %s", dbtemp, dbname); 200 (void)unlink(dbtemp); 201 return(1); 202 } 203 204 return(0); 205 } 206 207 __dead void 208 usage(void) 209 { 210 (void)fprintf(stderr, "usage: kvm_mkdb [-v] [-o directory] [file]\n"); 211 exit(1); 212 } 213