1 /* $NetBSD: passwd.c,v 1.9 1997/07/06 18:17:21 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1987, 1993, 1994, 1995 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 #if defined(LIBC_SCCS) && !defined(lint) 38 __RCSID("$NetBSD: passwd.c,v 1.9 1997/07/06 18:17:21 christos Exp $"); 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 #include <sys/time.h> 44 #include <sys/resource.h> 45 #include <sys/wait.h> 46 47 #include <ctype.h> 48 #include <err.h> 49 #include <fcntl.h> 50 #include <unistd.h> 51 #include <stdlib.h> 52 #include <stdio.h> 53 #include <string.h> 54 #include <pwd.h> 55 #include <errno.h> 56 #include <paths.h> 57 #include <signal.h> 58 #include <limits.h> 59 #include <util.h> 60 61 static void pw_cont __P((int sig)); 62 63 int 64 pw_lock(retries) 65 int retries; 66 { 67 int i, fd; 68 mode_t old_mode; 69 70 /* Acquire the lock file. */ 71 old_mode = umask(0); 72 fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL, 0600); 73 for (i = 0; i < retries && fd < 0 && errno == EEXIST; i++) { 74 sleep(1); 75 fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL, 76 0600); 77 } 78 umask(old_mode); 79 return(fd); 80 } 81 82 int 83 pw_mkdb() 84 { 85 int pstat; 86 pid_t pid; 87 88 pid = vfork(); 89 if (pid == 0) { 90 execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p", 91 _PATH_MASTERPASSWD_LOCK, NULL); 92 exit(1); 93 } 94 pid = waitpid(pid, &pstat, 0); 95 if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0) 96 return(-1); 97 return(0); 98 } 99 100 int 101 pw_abort() 102 { 103 return(unlink(_PATH_MASTERPASSWD_LOCK)); 104 } 105 106 /* Everything below this point is intended for the convenience of programs 107 * which allow a user to interactively edit the passwd file. Errors in the 108 * routines below will cause the process to abort. */ 109 110 static pid_t editpid = -1; 111 112 static void 113 pw_cont(sig) 114 int sig; 115 { 116 117 if (editpid != -1) 118 kill(editpid, sig); 119 } 120 121 void 122 pw_init() 123 { 124 struct rlimit rlim; 125 126 /* Unlimited resource limits. */ 127 rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY; 128 (void)setrlimit(RLIMIT_CPU, &rlim); 129 (void)setrlimit(RLIMIT_FSIZE, &rlim); 130 (void)setrlimit(RLIMIT_STACK, &rlim); 131 (void)setrlimit(RLIMIT_DATA, &rlim); 132 (void)setrlimit(RLIMIT_RSS, &rlim); 133 134 /* Don't drop core (not really necessary, but GP's). */ 135 rlim.rlim_cur = rlim.rlim_max = 0; 136 (void)setrlimit(RLIMIT_CORE, &rlim); 137 138 /* Turn off signals. */ 139 (void)signal(SIGALRM, SIG_IGN); 140 (void)signal(SIGHUP, SIG_IGN); 141 (void)signal(SIGINT, SIG_IGN); 142 (void)signal(SIGPIPE, SIG_IGN); 143 (void)signal(SIGQUIT, SIG_IGN); 144 (void)signal(SIGTERM, SIG_IGN); 145 (void)signal(SIGCONT, pw_cont); 146 } 147 148 void 149 pw_edit(notsetuid, filename) 150 int notsetuid; 151 const char *filename; 152 { 153 int i, xargc, pstat; 154 char *p, *editor; 155 char **xargv; 156 #ifdef __GNUC__ 157 (void) &editor; 158 #endif 159 160 if (filename == NULL) 161 filename = _PATH_MASTERPASSWD_LOCK; 162 if ((editor = getenv("EDITOR")) == NULL) 163 editor = strdup(_PATH_VI); 164 else 165 editor = strdup(editor); 166 if ((p = strrchr(editor, '/'))) 167 ++p; 168 else 169 p = editor; 170 171 /* Scan editor string, count spaces, allocate arg vector. */ 172 for (i = 0, xargc = 0; p[i] != '\0'; i++) { 173 if (isspace(p[i])) { 174 while (isspace(p[i++])) 175 /* skip white space */ ; 176 if (p[i] == '\0') 177 break; 178 xargc++; 179 } 180 } 181 182 /* argv[0] + <xargc args> + filename + NULL */ 183 xargv = (char **)malloc(sizeof(char *) * (xargc + 3)); 184 if (xargv == NULL) 185 pw_error("malloc failed", 1, 1); 186 187 i = 0; 188 xargv[i++] = p; 189 for (; *p != '\0'; p++) { 190 if (isspace(*p)) { 191 while(isspace(*p)) 192 *p++ = '\0'; /* blast whitespace */ 193 if (*p == '\0') 194 break; 195 xargv[i++] = p; 196 } 197 } 198 199 xargv[i++] = (char *)filename; 200 xargv[i] = NULL; 201 202 if (!(editpid = vfork())) { 203 if (notsetuid) { 204 setgid(getgid()); 205 setuid(getuid()); 206 } 207 execvp(editor, xargv); 208 _exit(1); 209 } 210 for (;;) { 211 editpid = waitpid(editpid, (int *)&pstat, WUNTRACED); 212 if (editpid == -1) 213 pw_error(editor, 1, 1); 214 else if (WIFSTOPPED(pstat)) 215 raise(WSTOPSIG(pstat)); 216 else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0) 217 break; 218 else 219 pw_error(editor, 1, 1); 220 } 221 editpid = -1; 222 free(editor); 223 free(xargv); 224 } 225 226 void 227 pw_prompt() 228 { 229 int c; 230 231 (void)printf("re-edit the password file? [y]: "); 232 (void)fflush(stdout); 233 c = getchar(); 234 if (c != EOF && c != '\n') 235 while (getchar() != '\n'); 236 if (c == 'n') 237 pw_error(NULL, 0, 0); 238 } 239 240 void 241 pw_copy(ffd, tfd, pw) 242 int ffd, tfd; 243 struct passwd *pw; 244 { 245 FILE *from, *to; 246 int done; 247 char *p, buf[8192]; 248 249 if (!(from = fdopen(ffd, "r"))) 250 pw_error(_PATH_MASTERPASSWD, 1, 1); 251 if (!(to = fdopen(tfd, "w"))) 252 pw_error(_PATH_MASTERPASSWD_LOCK, 1, 1); 253 254 for (done = 0; fgets(buf, sizeof(buf), from);) { 255 if (!strchr(buf, '\n')) { 256 warnx("%s: line too long", _PATH_MASTERPASSWD); 257 pw_error(NULL, 0, 1); 258 } 259 if (done) { 260 (void)fprintf(to, "%s", buf); 261 if (ferror(to)) 262 goto err; 263 continue; 264 } 265 if (!(p = strchr(buf, ':'))) { 266 warnx("%s: corrupted entry", _PATH_MASTERPASSWD); 267 pw_error(NULL, 0, 1); 268 } 269 *p = '\0'; 270 if (strcmp(buf, pw->pw_name)) { 271 *p = ':'; 272 (void)fprintf(to, "%s", buf); 273 if (ferror(to)) 274 goto err; 275 continue; 276 } 277 (void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", 278 pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid, 279 pw->pw_class, (long)pw->pw_change, (long)pw->pw_expire, 280 pw->pw_gecos, pw->pw_dir, pw->pw_shell); 281 done = 1; 282 if (ferror(to)) 283 goto err; 284 } 285 if (!done) 286 (void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n", 287 pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid, 288 pw->pw_class, (long)pw->pw_change, (long)pw->pw_expire, 289 pw->pw_gecos, pw->pw_dir, pw->pw_shell); 290 291 if (ferror(to)) 292 err: pw_error(NULL, 1, 1); 293 (void)fclose(to); 294 } 295 296 int 297 pw_scan(bp, pw, flags) 298 char *bp; 299 struct passwd *pw; 300 int *flags; 301 { 302 unsigned long id; 303 int root; 304 char *p, *sh, *ep; 305 306 if (flags != (int *)NULL) 307 *flags = 0; 308 309 if (!(pw->pw_name = strsep(&bp, ":"))) /* login */ 310 goto fmt; 311 root = !strcmp(pw->pw_name, "root"); 312 313 if (!(pw->pw_passwd = strsep(&bp, ":"))) /* passwd */ 314 goto fmt; 315 316 if (!(p = strsep(&bp, ":"))) /* uid */ 317 goto fmt; 318 id = strtoul(p, &ep, 10); 319 if (root && id) { 320 warnx("root uid should be 0"); 321 return (0); 322 } 323 if (id > UID_MAX || *ep != '\0') { 324 warnx("invalid uid '%s'", p); 325 return (0); 326 } 327 pw->pw_uid = (uid_t)id; 328 if ((*p == '\0') && (flags != (int *)NULL)) 329 *flags |= _PASSWORD_NOUID; 330 331 if (!(p = strsep(&bp, ":"))) /* gid */ 332 goto fmt; 333 id = strtoul(p, &ep, 10); 334 if (id > GID_MAX || *ep != '\0') { 335 warnx("invalid gid '%s'", p); 336 return (0); 337 } 338 pw->pw_gid = (gid_t)id; 339 if ((*p == '\0') && (flags != (int *)NULL)) 340 *flags |= _PASSWORD_NOGID; 341 342 pw->pw_class = strsep(&bp, ":"); /* class */ 343 if (!(p = strsep(&bp, ":"))) /* change */ 344 goto fmt; 345 pw->pw_change = atol(p); 346 if ((*p == '\0') && (flags != (int *)NULL)) 347 *flags |= _PASSWORD_NOCHG; 348 if (!(p = strsep(&bp, ":"))) /* expire */ 349 goto fmt; 350 pw->pw_expire = atol(p); 351 if ((*p == '\0') && (flags != (int *)NULL)) 352 *flags |= _PASSWORD_NOEXP; 353 pw->pw_gecos = strsep(&bp, ":"); /* gecos */ 354 pw->pw_dir = strsep(&bp, ":"); /* directory */ 355 if (!(pw->pw_shell = strsep(&bp, ":"))) /* shell */ 356 goto fmt; 357 358 p = pw->pw_shell; 359 if (root && *p) /* empty == /bin/sh */ 360 for (setusershell();;) { 361 if (!(sh = getusershell())) { 362 warnx("warning, unknown root shell"); 363 break; 364 } 365 if (!strcmp(p, sh)) 366 break; 367 } 368 369 if ((p = strsep(&bp, ":"))) { /* too many */ 370 fmt: warnx("corrupted entry"); 371 return (0); 372 } 373 374 return (1); 375 } 376 377 void 378 pw_error(name, err, eval) 379 const char *name; 380 int err, eval; 381 { 382 if (err) 383 warn(name); 384 385 warnx("%s: unchanged", _PATH_MASTERPASSWD); 386 pw_abort(); 387 exit(eval); 388 } 389 390