From bd4634fe5dc7808ab33b20afb9d42dcc36f0b4d9 Mon Sep 17 00:00:00 2001 From: Eitan Adler Date: Thu, 15 Nov 2012 15:06:18 +0000 Subject: Avoid possible null deref if ypclnt_new returns null PR: bin/172979 Submitted by: Erik Cederstrand Approved by: cperciva MFC after: 3 days --- chpass/chpass.c | 305 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 305 insertions(+) create mode 100644 chpass/chpass.c (limited to 'chpass/chpass.c') diff --git a/chpass/chpass.c b/chpass/chpass.c new file mode 100644 index 0000000..9f9be53 --- /dev/null +++ b/chpass/chpass.c @@ -0,0 +1,305 @@ +/*- + * Copyright (c) 1988, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * Copyright (c) 2002 Networks Associates Technology, Inc. + * All rights reserved. + * + * Portions of this software were developed for the FreeBSD Project by + * ThinkSec AS and NAI Labs, the Security Research Division of Network + * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 + * ("CBOSS"), as part of the DARPA CHATS research program. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if 0 +#ifndef lint +static const char copyright[] = +"@(#) Copyright (c) 1988, 1993, 1994\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +static char sccsid[] = "@(#)chpass.c 8.4 (Berkeley) 4/2/94"; +#endif /* not lint */ +#endif +#include +__FBSDID("$FreeBSD$"); + +#include + +#include +#include +#include +#include +#include +#include +#include +#ifdef YP +#include +#endif + +#include +#include + +#include "chpass.h" + +int master_mode; + +static void baduser(void); +static void usage(void); + +int +main(int argc, char *argv[]) +{ + enum { NEWSH, LOADENTRY, EDITENTRY, NEWPW, NEWEXP } op; + struct passwd lpw, *old_pw, *pw; + int ch, pfd, tfd; + const char *password; + char *arg = NULL; + uid_t uid; +#ifdef YP + struct ypclnt *ypclnt; + const char *yp_domain = NULL, *yp_host = NULL; +#endif + + pw = old_pw = NULL; + op = EDITENTRY; +#ifdef YP + while ((ch = getopt(argc, argv, "a:p:s:e:d:h:loy")) != -1) +#else + while ((ch = getopt(argc, argv, "a:p:s:e:")) != -1) +#endif + switch (ch) { + case 'a': + op = LOADENTRY; + arg = optarg; + break; + case 's': + op = NEWSH; + arg = optarg; + break; + case 'p': + op = NEWPW; + arg = optarg; + break; + case 'e': + op = NEWEXP; + arg = optarg; + break; +#ifdef YP + case 'd': + yp_domain = optarg; + break; + case 'h': + yp_host = optarg; + break; + case 'l': + case 'o': + case 'y': + /* compatibility */ + break; +#endif + case '?': + default: + usage(); + } + + argc -= optind; + argv += optind; + + if (argc > 1) + usage(); + + uid = getuid(); + + if (op == EDITENTRY || op == NEWSH || op == NEWPW || op == NEWEXP) { + if (argc == 0) { + if ((pw = getpwuid(uid)) == NULL) + errx(1, "unknown user: uid %lu", + (unsigned long)uid); + } else { + if ((pw = getpwnam(*argv)) == NULL) + errx(1, "unknown user: %s", *argv); + if (uid != 0 && uid != pw->pw_uid) + baduser(); + } + + /* Make a copy for later verification */ + if ((pw = pw_dup(pw)) == NULL || + (old_pw = pw_dup(pw)) == NULL) + err(1, "pw_dup"); + } + +#ifdef YP + if (pw != NULL && (pw->pw_fields & _PWF_SOURCE) == _PWF_NIS) { + ypclnt = ypclnt_new(yp_domain, "passwd.byname", yp_host); + master_mode = (ypclnt != NULL && + ypclnt_connect(ypclnt) != -1 && + ypclnt_havepasswdd(ypclnt) == 1); + ypclnt_free(ypclnt); + } else +#endif + master_mode = (uid == 0); + + if (op == NEWSH) { + /* protect p_shell -- it thinks NULL is /bin/sh */ + if (!arg[0]) + usage(); + if (p_shell(arg, pw, (ENTRY *)NULL) == -1) + exit(1); + } + + if (op == NEWEXP) { + if (uid) /* only root can change expire */ + baduser(); + if (p_expire(arg, pw, (ENTRY *)NULL) == -1) + exit(1); + } + + if (op == LOADENTRY) { + if (uid) + baduser(); + pw = &lpw; + old_pw = NULL; + if (!__pw_scan(arg, pw, _PWSCAN_WARN|_PWSCAN_MASTER)) + exit(1); + } + + if (op == NEWPW) { + if (uid) + baduser(); + + if (strchr(arg, ':')) + errx(1, "invalid format for password"); + pw->pw_passwd = arg; + } + + if (op == EDITENTRY) { + /* + * We don't really need pw_*() here, but pw_edit() (used + * by edit()) is just too useful... + */ + if (pw_init(NULL, NULL)) + err(1, "pw_init()"); + if ((tfd = pw_tmp(-1)) == -1) { + pw_fini(); + err(1, "pw_tmp()"); + } + free(pw); + pw = edit(pw_tempname(), old_pw); + pw_fini(); + if (pw == NULL) + err(1, "edit()"); + /* + * pw_equal does not check for crypted passwords, so we + * should do it explicitly + */ + if (pw_equal(old_pw, pw) && + strcmp(old_pw->pw_passwd, pw->pw_passwd) == 0) + errx(0, "user information unchanged"); + } + + if (old_pw && !master_mode) { + password = getpass("Password: "); + if (strcmp(crypt(password, old_pw->pw_passwd), + old_pw->pw_passwd) != 0) + baduser(); + } else { + password = ""; + } + + if (old_pw != NULL) + pw->pw_fields |= (old_pw->pw_fields & _PWF_SOURCE); + switch (pw->pw_fields & _PWF_SOURCE) { +#ifdef YP + case _PWF_NIS: + ypclnt = ypclnt_new(yp_domain, "passwd.byname", yp_host); + if (ypclnt == NULL) { + warnx("ypclnt_new failed"); + exit(1); + } + if (ypclnt_connect(ypclnt) == -1 || + ypclnt_passwd(ypclnt, pw, password) == -1) { + warnx("%s", ypclnt->error); + ypclnt_free(ypclnt); + exit(1); + } + ypclnt_free(ypclnt); + errx(0, "NIS user information updated"); +#endif /* YP */ + case 0: + case _PWF_FILES: + if (pw_init(NULL, NULL)) + err(1, "pw_init()"); + if ((pfd = pw_lock()) == -1) { + pw_fini(); + err(1, "pw_lock()"); + } + if ((tfd = pw_tmp(-1)) == -1) { + pw_fini(); + err(1, "pw_tmp()"); + } + if (pw_copy(pfd, tfd, pw, old_pw) == -1) { + pw_fini(); + err(1, "pw_copy"); + } + if (pw_mkdb(pw->pw_name) == -1) { + pw_fini(); + err(1, "pw_mkdb()"); + } + pw_fini(); + errx(0, "user information updated"); + break; + default: + errx(1, "unsupported passwd source"); + } +} + +static void +baduser(void) +{ + + errx(1, "%s", strerror(EACCES)); +} + +static void +usage(void) +{ + + (void)fprintf(stderr, + "usage: chpass%s %s [user]\n", +#ifdef YP + " [-d domain] [-h host]", +#else + "", +#endif + "[-a list] [-p encpass] [-s shell] [-e mmm dd yy]"); + exit(1); +} -- cgit v1.2.3-56-ge451