1 /*- 2 * Copyright (c) 1988, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static char copyright[] = 36 "@(#) Copyright (c) 1988, 1993, 1994\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 static char sccsid[] = "@(#)chpass.c 8.4 (Berkeley) 4/2/94"; 42 #endif /* not lint */ 43 44 #include <sys/param.h> 45 #include <sys/stat.h> 46 #include <sys/signal.h> 47 #include <sys/time.h> 48 #include <sys/resource.h> 49 50 #include <ctype.h> 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <pwd.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 #include <pw_scan.h> 61 #include <pw_util.h> 62 #include "pw_copy.h" 63 64 #include "chpass.h" 65 #include "pathnames.h" 66 67 char *progname = "chpass"; 68 char *tempname; 69 uid_t uid; 70 71 void baduser __P((void)); 72 void usage __P((void)); 73 74 int 75 main(argc, argv) 76 int argc; 77 char **argv; 78 { 79 enum { NEWSH, LOADENTRY, EDITENTRY } op; 80 struct passwd *pw, lpw; 81 int ch, pfd, tfd; 82 char *arg; 83 84 op = EDITENTRY; 85 while ((ch = getopt(argc, argv, "a:s:")) != EOF) 86 switch(ch) { 87 case 'a': 88 op = LOADENTRY; 89 arg = optarg; 90 break; 91 case 's': 92 op = NEWSH; 93 arg = optarg; 94 break; 95 case '?': 96 default: 97 usage(); 98 } 99 argc -= optind; 100 argv += optind; 101 102 uid = getuid(); 103 104 if (op == EDITENTRY || op == NEWSH) 105 switch(argc) { 106 case 0: 107 if (!(pw = getpwuid(uid))) 108 errx(1, "unknown user: uid %u", uid); 109 break; 110 case 1: 111 if (!(pw = getpwnam(*argv))) 112 errx(1, "unknown user: %s", *argv); 113 if (uid && uid != pw->pw_uid) 114 baduser(); 115 break; 116 default: 117 usage(); 118 } 119 120 if (op == NEWSH) { 121 /* protect p_shell -- it thinks NULL is /bin/sh */ 122 if (!arg[0]) 123 usage(); 124 if (p_shell(arg, pw, (ENTRY *)NULL)) 125 pw_error((char *)NULL, 0, 1); 126 } 127 128 if (op == LOADENTRY) { 129 if (uid) 130 baduser(); 131 pw = &lpw; 132 if (!pw_scan(arg, pw)) 133 exit(1); 134 } 135 136 /* 137 * The temporary file/file descriptor usage is a little tricky here. 138 * 1: We start off with two fd's, one for the master password 139 * file (used to lock everything), and one for a temporary file. 140 * 2: Display() gets an fp for the temporary file, and copies the 141 * user's information into it. It then gives the temporary file 142 * to the user and closes the fp, closing the underlying fd. 143 * 3: The user edits the temporary file some number of times. 144 * 4: Verify() gets an fp for the temporary file, and verifies the 145 * contents. It can't use an fp derived from the step #2 fd, 146 * because the user's editor may have created a new instance of 147 * the file. Once the file is verified, its contents are stored 148 * in a password structure. The verify routine closes the fp, 149 * closing the underlying fd. 150 * 5: Delete the temporary file. 151 * 6: Get a new temporary file/fd. Pw_copy() gets an fp for it 152 * file and copies the master password file into it, replacing 153 * the user record with a new one. We can't use the first 154 * temporary file for this because it was owned by the user. 155 * Pw_copy() closes its fp, flushing the data and closing the 156 * underlying file descriptor. We can't close the master 157 * password fp, or we'd lose the lock. 158 * 7: Call pw_mkdb() (which renames the temporary file) and exit. 159 * The exit closes the master passwd fp/fd. 160 */ 161 pw_init(); 162 pfd = pw_lock(); 163 tfd = pw_tmp(); 164 165 if (op == EDITENTRY) { 166 display(tfd, pw); 167 edit(pw); 168 (void)unlink(tempname); 169 tfd = pw_tmp(); 170 } 171 172 pw_copy(pfd, tfd, pw); 173 174 if (!pw_mkdb()) 175 pw_error((char *)NULL, 0, 1); 176 exit(0); 177 } 178 179 void 180 baduser() 181 { 182 183 errx(1, "%s", strerror(EACCES)); 184 } 185 186 void 187 usage() 188 { 189 190 (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [user]\n"); 191 exit(1); 192 } 193