diff options
Diffstat (limited to 'libmisc/setugid.c')
| -rw-r--r-- | libmisc/setugid.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/libmisc/setugid.c b/libmisc/setugid.c new file mode 100644 index 0000000..9bb62af --- /dev/null +++ b/libmisc/setugid.c @@ -0,0 +1,148 @@ +/* + * Copyright (c) 1989 - 1994, Julianne Frances Haugh + * Copyright (c) 1996 - 1998, Marek Michałkiewicz + * Copyright (c) 2003 - 2005, Tomasz Kłoczko + * Copyright (c) 2008 - 2010, Nicolas François + * All rights reserved. + * + * 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. The name of the copyright holders or contributors may not be used to + * endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT + * HOLDERS 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. + */ + +/* + * Separated from setup.c. --marekm + */ + +#include <config.h> + +#ident "$Id$" + +#include <stdio.h> +#include <grp.h> +#include <errno.h> +#include "prototypes.h" +#include "defines.h" +#include <pwd.h> +#include "getdef.h" + +/* + * setup_groups - set the group credentials + * set the group ID to the value from the password file entry + * set the supplementary group IDs + * + * In case of PAM enabled configurations, this shall be called before + * pam_setcred. + * + * Returns 0 on success, or -1 on failure. + */ +int setup_groups (const struct passwd *info) +{ + /* + * Set the real group ID to the primary group ID in the password + * file. + */ + if (setgid (info->pw_gid) == -1) { + int err = errno; + perror ("setgid"); + SYSLOG ((LOG_ERR, "bad group ID `%d' for user `%s': %s\n", + info->pw_gid, info->pw_name, strerror (err))); + closelog (); + return -1; + } +#ifdef HAVE_INITGROUPS + /* + * For systems which support multiple concurrent groups, go get + * the group set from the /etc/group file. + */ + if (initgroups (info->pw_name, info->pw_gid) == -1) { + int err = errno; + perror ("initgroups"); + SYSLOG ((LOG_ERR, "initgroups failed for user `%s': %s\n", + info->pw_name, strerror (err))); + closelog (); + return -1; + } +#endif + return 0; +} + +/* + * change_uid - Set the real UID + * + * Returns 0 on success, or -1 on failure. + */ +int change_uid (const struct passwd *info) +{ + /* + * Set the real UID to the UID value in the password file. + */ + if (setuid (info->pw_uid) != 0) { + int err = errno; + perror ("setuid"); + SYSLOG ((LOG_ERR, "bad user ID `%d' for user `%s': %s\n", + (int) info->pw_uid, info->pw_name, strerror (err))); + closelog (); + return -1; + } + return 0; +} + +/* + * setup_uid_gid() performs the following steps - + * + * set the group ID to the value from the password file entry + * set the supplementary group IDs + * optionally call specified function which may add more groups + * set the user ID to the value from the password file entry + * + * Returns 0 on success, or -1 on failure. + */ + +#if defined (HAVE_INITGROUPS) && ! (defined USE_PAM) +int setup_uid_gid (const struct passwd *info, bool is_console) +#else +int setup_uid_gid (const struct passwd *info) +#endif +{ + if (setup_groups (info) < 0) { + return -1; + } + +#if defined (HAVE_INITGROUPS) && ! defined (USE_PAM) + if (is_console) { + const char *cp = getdef_str ("CONSOLE_GROUPS"); + + if ((NULL != cp) && (add_groups (cp) != 0)) { + perror ("Warning: add_groups"); + } + } +#endif /* HAVE_INITGROUPS && !USE_PAM*/ + + if (change_uid (info) < 0) { + return -1; + } + + return 0; +} + |