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/* Copyright (C) 2007-2010 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Gurvinder Singh <gurvindersinghdahiya@gmail.com>
*
* File to drop the engine capabilities using libcap-ng by
* Steve Grubb
*/
#ifndef OS_WIN32
#include <grp.h>
#include <pwd.h>
#include "util-debug.h"
#include "suricata-common.h"
#include "suricata.h"
#ifdef HAVE_LIBCAP_NG
#include <cap-ng.h>
#ifdef HAVE_SYS_PRCTL_H
#include <sys/prctl.h>
#endif
#include "threadvars.h"
#include "util-cpu.h"
#include "util-privs.h"
#include "runmodes.h"
/** flag indicating if we'll be using caps */
extern int sc_set_caps;
/** our current runmode */
extern int run_mode;
/**
* \brief Drop all the previliges of the given thread
*/
void SCDropAllCaps()
{
capng_clear(CAPNG_SELECT_BOTH);
if (capng_apply(CAPNG_SELECT_BOTH) < 0) {
SCLogError(SC_ERR_CHANGING_CAPS_FAILED, "failed in dropping the caps");
exit(EXIT_FAILURE);
}
}
/**
* \brief Drop the previliges of the main thread
*/
void SCDropMainThreadCaps(uint32_t userid, uint32_t groupid)
{
if (sc_set_caps == FALSE)
return;
capng_clear(CAPNG_SELECT_BOTH);
switch (run_mode) {
case RUNMODE_PCAP_DEV:
case RUNMODE_AFP_DEV:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_RAW, /* needed for pcap live mode */
-1);
break;
case RUNMODE_PFRING:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_ADMIN, CAP_NET_RAW,
-1);
break;
case RUNMODE_NFQ:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_ADMIN, /* needed for nfqueue inline mode */
-1);
break;
}
if (capng_change_id(userid, groupid, CAPNG_DROP_SUPP_GRP |
CAPNG_CLEAR_BOUNDING) < 0)
{
SCLogError(SC_ERR_CHANGING_CAPS_FAILED, "capng_change_id for main thread"
" failed");
exit(EXIT_FAILURE);
}
SCLogInfo("dropped the caps for main thread");
}
void SCDropCaps(ThreadVars *tv)
{
#if 0
capng_clear(CAPNG_SELECT_BOTH);
capng_apply(CAPNG_SELECT_BOTH);
if (tv->cap_flags & SC_CAP_IPC_LOCK) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_IPC_LOCK);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_IPC_LOCK has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_ADMIN) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_ADMIN);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_ADMIN has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_BIND_SERVICE) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_BIND_SERVICE);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_BIND_SERVICE has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_BROADCAST) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_BROADCAST);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_BROADCAST has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_RAW) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_RAW);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_RAW has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_SYS_ADMIN) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_SYS_ADMIN);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_SYS_ADMIN has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_SYS_RAW_IO) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_SYS_RAWIO);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_SYS_RAWIO has been set", tv->name);
}
#endif
}
#endif /* HAVE_LIBCAP_NG */
/**
* \brief Function to get the user and group ID from the specified user name
*
* \param user_name pointer to the given user name
* \param uid pointer to the user id in which result will be stored
* \param gid pointer to the group id in which result will be stored
*
* \retval upon success it return 0
*/
int SCGetUserID(char *user_name, char *group_name, uint32_t *uid, uint32_t *gid)
{
uint32_t userid = 0;
uint32_t groupid = 0;
struct passwd *pw;
/* Get the user ID */
if (isdigit((unsigned char)user_name[0]) != 0) {
userid = atoi(user_name);
pw = getpwuid(userid);
if (pw == NULL) {
SCLogError(SC_ERR_UID_FAILED, "unable to get the user ID, "
"check if user exist!!");
exit(EXIT_FAILURE);
}
} else {
pw = getpwnam(user_name);
if (pw == NULL) {
SCLogError(SC_ERR_UID_FAILED, "unable to get the user ID, "
"check if user exist!!");
exit(EXIT_FAILURE);
}
userid = pw->pw_uid;
}
/* Get the group ID */
if (group_name != NULL) {
struct group *gp;
if (isdigit((unsigned char)group_name[0]) != 0) {
groupid = atoi(group_name);
} else {
gp = getgrnam(group_name);
if (gp == NULL) {
SCLogError(SC_ERR_GID_FAILED, "unable to get the group"
" ID, check if group exist!!");
exit(EXIT_FAILURE);
}
groupid = gp->gr_gid;
}
} else {
groupid = pw->pw_gid;
}
/* close the group database */
endgrent();
/* close the user database */
endpwent();
*uid = userid;
*gid = groupid;
return 0;
}
/**
* \brief Function to get the group ID from the specified group name
*
* \param group_name pointer to the given group name
* \param gid pointer to the group id in which result will be stored
*
* \retval upon success it return 0
*/
int SCGetGroupID(char *group_name, uint32_t *gid)
{
uint32_t grpid = 0;
struct group *gp;
/* Get the group ID */
if (isdigit((unsigned char)group_name[0]) != 0) {
grpid = atoi(group_name);
} else {
gp = getgrnam(group_name);
if (gp == NULL) {
SCLogError(SC_ERR_GID_FAILED, "unable to get the group ID,"
" check if group exist!!");
exit(EXIT_FAILURE);
}
grpid = gp->gr_gid;
}
/* close the group database */
endgrent();
*gid = grpid;
return 0;
}
#endif /* OS_WIN32 */
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