sudo/plugins/group_file/group_file.c

130 lines
3.2 KiB
C

/*
* SPDX-License-Identifier: ISC
*
* Copyright (c) 2010-2014 Todd C. Miller <Todd.Miller@sudo.ws>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
*/
#include <config.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STDBOOL_H
# include <stdbool.h>
#else
# include <compat/stdbool.h>
#endif /* HAVE_STDBOOL_H */
#include <string.h>
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <sudo_plugin.h>
#include <sudo_compat.h>
/*
* Sample sudoers group plugin that uses an extra group file with the
* same format as /etc/group.
*/
static sudo_printf_t sudo_log;
extern void mysetgrfile(const char *);
extern int mysetgroupent(int);
extern void myendgrent(void);
extern struct group *mygetgrnam(const char *);
static int
sample_init(int version, sudo_printf_t sudo_printf, char *const argv[])
{
struct stat sb;
sudo_log = sudo_printf;
if (SUDO_API_VERSION_GET_MAJOR(version) != GROUP_API_VERSION_MAJOR) {
sudo_log(SUDO_CONV_ERROR_MSG,
"group_file: incompatible major version %d, expected %d\n",
SUDO_API_VERSION_GET_MAJOR(version),
GROUP_API_VERSION_MAJOR);
return -1;
}
/* Check that the group file exists and has a safe mode. */
if (argv == NULL || argv[0] == NULL) {
sudo_log(SUDO_CONV_ERROR_MSG,
"group_file: path to group file not specified\n");
return -1;
}
if (stat(argv[0], &sb) != 0) {
sudo_log(SUDO_CONV_ERROR_MSG,
"group_file: %s: %s\n", argv[0], strerror(errno));
return -1;
}
if ((sb.st_mode & (S_IWGRP|S_IWOTH)) != 0) {
sudo_log(SUDO_CONV_ERROR_MSG,
"%s must be only be writable by owner\n", argv[0]);
return -1;
}
mysetgrfile(argv[0]);
if (!mysetgroupent(1))
return false;
return true;
}
static void
sample_cleanup(void)
{
myendgrent();
}
/*
* Returns true if "user" is a member of "group", else false.
*/
static int
sample_query(const char *user, const char *group, const struct passwd *pwd)
{
struct group *grp;
char **member;
grp = mygetgrnam(group);
if (grp != NULL && grp->gr_mem != NULL) {
for (member = grp->gr_mem; *member != NULL; member++) {
if (strcasecmp(user, *member) == 0)
return true;
}
}
return false;
}
sudo_dso_public struct sudoers_group_plugin group_plugin = {
GROUP_API_VERSION,
sample_init,
sample_cleanup,
sample_query
};