1 /* $NetBSD: chpass.c,v 1.22 2001/08/18 19:35:34 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 1988, 1993, 1994 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\n\ 39 The Regents of the University of California. All rights reserved.\n"); 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)chpass.c 8.4 (Berkeley) 4/2/94"; 45 #else 46 __RCSID("$NetBSD: chpass.c,v 1.22 2001/08/18 19:35:34 ad Exp $"); 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/param.h> 51 #include <sys/stat.h> 52 #include <sys/time.h> 53 #include <sys/resource.h> 54 55 #include <ctype.h> 56 #include <err.h> 57 #include <errno.h> 58 #include <fcntl.h> 59 #include <pwd.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <unistd.h> 64 #include <util.h> 65 66 #include "chpass.h" 67 #include "pathnames.h" 68 69 char *tempname; 70 uid_t uid; 71 int use_yp; 72 int yflag; 73 74 void (*Pw_error) __P((const char *, int, int)); 75 76 #ifdef YP 77 extern int _yp_check __P((char **)); /* buried deep inside libc */ 78 #endif 79 80 void baduser __P((void)); 81 int main __P((int, char **)); 82 void usage __P((void)); 83 84 int 85 main(argc, argv) 86 int argc; 87 char **argv; 88 { 89 enum { NEWSH, LOADENTRY, EDITENTRY } op; 90 struct passwd *pw, lpw, old_pw; 91 int ch, pfd, tfd, dfd; 92 char *arg, *username = NULL, tempname[] = "/etc/pw.XXXXXX"; 93 94 #ifdef __GNUC__ 95 pw = NULL; /* XXX gcc -Wuninitialized */ 96 arg = NULL; 97 #endif 98 #ifdef YP 99 use_yp = _yp_check(NULL); 100 #endif 101 102 op = EDITENTRY; 103 while ((ch = getopt(argc, argv, "a:s:ly")) != -1) 104 switch(ch) { 105 case 'a': 106 op = LOADENTRY; 107 arg = optarg; 108 break; 109 case 's': 110 op = NEWSH; 111 arg = optarg; 112 break; 113 case 'l': 114 use_yp = 0; 115 break; 116 case 'y': 117 #ifdef YP 118 if (!use_yp) 119 errx(1, "YP not in use."); 120 yflag = 1; 121 #else 122 errx(1, "YP support not compiled in."); 123 #endif 124 break; 125 default: 126 usage(); 127 } 128 argc -= optind; 129 argv += optind; 130 131 uid = getuid(); 132 switch (argc) { 133 case 0: 134 /* nothing */ 135 break; 136 137 case 1: 138 username = argv[0]; 139 break; 140 141 default: 142 usage(); 143 } 144 145 #ifdef YP 146 /* 147 * We need to determine if we _really_ want to use YP. 148 * If we defaulted to YP (i.e. were not given the -y flag), 149 * and the master is not running rpc.yppasswdd, we check 150 * to see if the user exists in the local passwd database. 151 * If so, we use it, otherwise we error out. 152 */ 153 if (use_yp && yflag == 0) { 154 if (check_yppasswdd()) { 155 /* 156 * We weren't able to contact rpc.yppasswdd. 157 * Check to see if we're in the local 158 * password database. If we are, use it. 159 */ 160 if (username != NULL) 161 pw = getpwnam(username); 162 else 163 pw = getpwuid(uid); 164 if (pw != NULL) 165 use_yp = 0; 166 else { 167 errx(1, "master YP server not running yppasswd daemon.\n\t%s\n", 168 "Can't change password."); 169 } 170 } 171 } 172 #endif 173 174 #ifdef YP 175 if (use_yp) 176 Pw_error = yppw_error; 177 else 178 #endif 179 Pw_error = pw_error; 180 181 #ifdef YP 182 if (op == LOADENTRY && use_yp) 183 errx(1, "cannot load entry using YP.\n\tUse the -l flag to load local."); 184 #endif 185 186 if (op == EDITENTRY || op == NEWSH) { 187 if (username != NULL) { 188 pw = getpwnam(username); 189 if (pw == NULL) 190 errx(1, "unknown user: %s", username); 191 if (uid && uid != pw->pw_uid) 192 baduser(); 193 } else { 194 pw = getpwuid(uid); 195 if (pw == NULL) 196 errx(1, "unknown user: uid %u\n", uid); 197 } 198 199 /* Make a copy for later verification */ 200 old_pw = *pw; 201 old_pw.pw_gecos = strdup(old_pw.pw_gecos); 202 } 203 204 if (op == NEWSH) { 205 /* protect p_shell -- it thinks NULL is /bin/sh */ 206 if (!arg[0]) 207 usage(); 208 if (p_shell(arg, pw, NULL)) 209 (*Pw_error)(NULL, 0, 1); 210 } 211 212 if (op == LOADENTRY) { 213 if (uid) 214 baduser(); 215 pw = &lpw; 216 if (!pw_scan(arg, pw, NULL)) 217 exit(1); 218 } 219 220 /* Edit the user passwd information if requested. */ 221 if (op == EDITENTRY) { 222 dfd = mkstemp(tempname); 223 if (dfd < 0 || fcntl(dfd, F_SETFD, 1) < 0) 224 (*Pw_error)(tempname, 1, 1); 225 display(tempname, dfd, pw); 226 edit(tempname, pw); 227 (void)unlink(tempname); 228 } 229 230 #ifdef YP 231 if (use_yp) { 232 if (pw_yp(pw, uid)) 233 yppw_error((char *)NULL, 0, 1); 234 else 235 exit(0); 236 /* Will not exit from this if. */ 237 } 238 #endif /* YP */ 239 240 241 /* 242 * Get the passwd lock file and open the passwd file for 243 * reading. 244 */ 245 pw_init(); 246 tfd = pw_lock(0); 247 if (tfd < 0) { 248 if (errno != EEXIST) 249 err(1, "%s", _PATH_MASTERPASSWD_LOCK); 250 warnx("The passwd file is busy, waiting..."); 251 tfd = pw_lock(10); 252 if (tfd < 0) { 253 if (errno != EEXIST) 254 err(1, "%s", _PATH_MASTERPASSWD_LOCK); 255 errx(1, "The passwd file is still busy, " 256 "try again later."); 257 } 258 } 259 if (fcntl(tfd, F_SETFD, 1) < 0) 260 pw_error(_PATH_MASTERPASSWD_LOCK, 1, 1); 261 262 pfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0); 263 if (pfd < 0 || fcntl(pfd, F_SETFD, 1) < 0) 264 pw_error(_PATH_MASTERPASSWD, 1, 1); 265 266 /* Copy the passwd file to the lock file, updating pw. */ 267 pw_copy(pfd, tfd, pw, (op == LOADENTRY) ? NULL : &old_pw); 268 269 /* Now finish the passwd file update. */ 270 if (pw_mkdb(username, 0) < 0) 271 pw_error(NULL, 0, 1); 272 273 exit(0); 274 } 275 276 void 277 baduser() 278 { 279 280 errx(1, "%s", strerror(EACCES)); 281 } 282 283 void 284 usage() 285 { 286 287 #ifdef YP 288 (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [-l]%s [user]\n", use_yp?" [-y]":""); 289 #else 290 (void)fprintf(stderr, "usage: chpass [-a list] [-s shell] [user]\n"); 291 #endif 292 exit(1); 293 } 294