shadow/lib/semanage.c
Christian Göttsche c80788a3ac useradd/usermod: add --selinux-range argument
Add a command line argument to useradd(8) and usermod(8) to specify the
MLS range for a SELinux user mapping.

Improves: #676
2023-04-19 09:19:19 +02:00

362 lines
7.9 KiB
C

/*
* SPDX-FileCopyrightText: 2010 , Jakub Hrozek <jhrozek@redhat.com>
* SPDX-FileCopyrightText: 2011 , Peter Vrabec <pvrabec@redhat.com>
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ifdef WITH_SELINUX
#include "defines.h"
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <stdio.h>
#include <stdarg.h>
#include <selinux/selinux.h>
#include <semanage/semanage.h>
#include "prototypes.h"
#include "shadowlog_internal.h"
format_attr(printf, 3, 4)
static void semanage_error_callback (unused void *varg,
semanage_handle_t *handle,
const char *fmt, ...)
{
int ret;
char * message = NULL;
va_list ap;
va_start (ap, fmt);
ret = vasprintf (&message, fmt, ap);
va_end (ap);
if (ret < 0) {
/* ENOMEM */
return;
}
switch (semanage_msg_get_level (handle)) {
case SEMANAGE_MSG_ERR:
case SEMANAGE_MSG_WARN:
fprintf (shadow_logfd, _("[libsemanage]: %s\n"), message);
break;
case SEMANAGE_MSG_INFO:
/* nop */
break;
}
free (message);
}
static semanage_handle_t *semanage_init (void)
{
int ret;
semanage_handle_t *handle = NULL;
handle = semanage_handle_create ();
if (NULL == handle) {
fprintf (shadow_logfd,
_("Cannot create SELinux management handle\n"));
return NULL;
}
semanage_msg_set_callback (handle, semanage_error_callback, NULL);
ret = semanage_is_managed (handle);
if (ret != 1) {
fprintf (shadow_logfd, _("SELinux policy not managed\n"));
goto fail;
}
ret = semanage_access_check (handle);
if (ret < SEMANAGE_CAN_READ) {
fprintf (shadow_logfd, _("Cannot read SELinux policy store\n"));
goto fail;
}
ret = semanage_connect (handle);
if (ret != 0) {
fprintf (shadow_logfd,
_("Cannot establish SELinux management connection\n"));
goto fail;
}
ret = semanage_begin_transaction (handle);
if (ret != 0) {
fprintf (shadow_logfd, _("Cannot begin SELinux transaction\n"));
goto fail;
}
return handle;
fail:
semanage_handle_destroy (handle);
return NULL;
}
static int semanage_user_mod (semanage_handle_t *handle,
semanage_seuser_key_t *key,
const char *login_name,
const char *seuser_name,
const char *serange)
{
int ret;
semanage_seuser_t *seuser = NULL;
semanage_seuser_query (handle, key, &seuser);
if (NULL == seuser) {
fprintf (shadow_logfd,
_("Could not query seuser for %s\n"), login_name);
ret = 1;
goto done;
}
if (serange && semanage_mls_enabled(handle)) {
ret = semanage_seuser_set_mlsrange (handle, seuser, serange);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not set serange for %s to %s\n"),
login_name, serange);
ret = 1;
goto done;
}
}
ret = semanage_seuser_set_sename (handle, seuser, seuser_name);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not set sename for %s\n"),
login_name);
ret = 1;
goto done;
}
ret = semanage_seuser_modify_local (handle, key, seuser);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not modify login mapping for %s\n"),
login_name);
ret = 1;
goto done;
}
ret = 0;
done:
semanage_seuser_free (seuser);
return ret;
}
static int semanage_user_add (semanage_handle_t *handle,
semanage_seuser_key_t *key,
const char *login_name,
const char *seuser_name,
const char *serange)
{
int ret;
semanage_seuser_t *seuser = NULL;
ret = semanage_seuser_create (handle, &seuser);
if (ret != 0) {
fprintf (shadow_logfd,
_("Cannot create SELinux login mapping for %s\n"),
login_name);
ret = 1;
goto done;
}
ret = semanage_seuser_set_name (handle, seuser, login_name);
if (ret != 0) {
fprintf (shadow_logfd, _("Could not set name for %s\n"), login_name);
ret = 1;
goto done;
}
if (serange && semanage_mls_enabled(handle)) {
ret = semanage_seuser_set_mlsrange (handle, seuser, serange);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not set serange for %s to %s\n"),
login_name, serange);
ret = 1;
goto done;
}
}
ret = semanage_seuser_set_sename (handle, seuser, seuser_name);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not set SELinux user for %s\n"),
login_name);
ret = 1;
goto done;
}
ret = semanage_seuser_modify_local (handle, key, seuser);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not add login mapping for %s\n"),
login_name);
ret = 1;
goto done;
}
ret = 0;
done:
semanage_seuser_free (seuser);
return ret;
}
int set_seuser (const char *login_name, const char *seuser_name, const char *serange)
{
semanage_handle_t *handle = NULL;
semanage_seuser_key_t *key = NULL;
int ret;
int seuser_exists = 0;
if (NULL == seuser_name) {
/* don't care, just let system pick the defaults */
return 0;
}
handle = semanage_init ();
if (NULL == handle) {
fprintf (shadow_logfd, _("Cannot init SELinux management\n"));
ret = 1;
goto done;
}
ret = semanage_seuser_key_create (handle, login_name, &key);
if (ret != 0) {
fprintf (shadow_logfd, _("Cannot create SELinux user key\n"));
ret = 1;
goto done;
}
ret = semanage_seuser_exists (handle, key, &seuser_exists);
if (ret < 0) {
fprintf (shadow_logfd, _("Cannot verify the SELinux user\n"));
ret = 1;
goto done;
}
if (0 != seuser_exists) {
ret = semanage_user_mod (handle, key, login_name, seuser_name, serange);
if (ret != 0) {
fprintf (shadow_logfd,
_("Cannot modify SELinux user mapping\n"));
ret = 1;
goto done;
}
} else {
ret = semanage_user_add (handle, key, login_name, seuser_name, serange);
if (ret != 0) {
fprintf (shadow_logfd,
_("Cannot add SELinux user mapping\n"));
ret = 1;
goto done;
}
}
ret = semanage_commit (handle);
if (ret < 0) {
fprintf (shadow_logfd, _("Cannot commit SELinux transaction\n"));
ret = 1;
goto done;
}
ret = 0;
reset_selinux_handle();
done:
semanage_seuser_key_free (key);
semanage_handle_destroy (handle);
return ret;
}
int del_seuser (const char *login_name)
{
semanage_handle_t *handle = NULL;
semanage_seuser_key_t *key = NULL;
int ret;
int exists = 0;
handle = semanage_init ();
if (NULL == handle) {
fprintf (shadow_logfd, _("Cannot init SELinux management\n"));
ret = 1;
goto done;
}
ret = semanage_seuser_key_create (handle, login_name, &key);
if (ret != 0) {
fprintf (shadow_logfd, _("Cannot create SELinux user key\n"));
ret = 1;
goto done;
}
ret = semanage_seuser_exists (handle, key, &exists);
if (ret < 0) {
fprintf (shadow_logfd, _("Cannot verify the SELinux user\n"));
ret = 1;
goto done;
}
if (0 == exists) {
fprintf (shadow_logfd,
_("Login mapping for %s is not defined, OK if default mapping was used\n"),
login_name);
ret = 0; /* probably default mapping */
goto done;
}
ret = semanage_seuser_exists_local (handle, key, &exists);
if (ret < 0) {
fprintf (shadow_logfd, _("Cannot verify the SELinux user\n"));
ret = 1;
goto done;
}
if (0 == exists) {
fprintf (shadow_logfd,
_("Login mapping for %s is defined in policy, cannot be deleted\n"),
login_name);
ret = 0; /* Login mapping defined in policy can't be deleted */
goto done;
}
ret = semanage_seuser_del_local (handle, key);
if (ret != 0) {
fprintf (shadow_logfd,
_("Could not delete login mapping for %s"),
login_name);
ret = 1;
goto done;
}
ret = semanage_commit (handle);
if (ret < 0) {
fprintf (shadow_logfd, _("Cannot commit SELinux transaction\n"));
ret = 1;
goto done;
}
ret = 0;
done:
semanage_handle_destroy (handle);
return ret;
}
#else /* !WITH_SELINUX */
extern int ISO_C_forbids_an_empty_translation_unit;
#endif /* !WITH_SELINUX */