/* Copyright (C) 2007-2016 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.

 */

/**

 * \ingroup sshlayer

 *

 * @{

 */

/**

 * \file

 *

 * \author Victor Julien <victor@inliniac.net>

 *

 * Implements support ssh_software sticky buffer

 */

#include "suricata-common.h"

#include "threads.h"

#include "decode.h"

#include "detect.h"

#include "detect-parse.h"

#include "detect-engine.h"

#include "detect-engine-buffer.h"

#include "detect-engine-mpm.h"

#include "detect-engine-state.h"

#include "detect-engine-prefilter.h"

#include "detect-engine-content-inspection.h"

#include "app-layer.h"

#include "app-layer-parser.h"

#include "app-layer-ssh.h"

#include "detect-ssh-software.h"

#include "rust.h"

#define KEYWORD_NAME "ssh.software"

#define KEYWORD_NAME_LEGACY "ssh_software"

#define KEYWORD_DOC "ssh-keywords.html#ssh-software"

#define BUFFER_NAME "ssh_software"

#define BUFFER_DESC "ssh software field"

static int g_buffer_id = 0;

static InspectionBuffer *GetSshData(DetectEngineThreadCtx *det_ctx,

        const DetectEngineTransforms *transforms, Flow *_f,

        const uint8_t flow_flags, void *txv, const int list_id)

{

    SCEnter();

    InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);

    if (buffer->inspect == NULL) {

        const uint8_t *software = NULL;

        uint32_t b_len = 0;

        if (SCSshTxGetSoftware(txv, &software, &b_len, flow_flags) != 1)

            return NULL;

        if (software == NULL || b_len == 0) {

            SCLogDebug("SSH software version not set");

            return NULL;

        }

        InspectionBufferSetupAndApplyTransforms(

                det_ctx, list_id, buffer, software, b_len, transforms);

    }

    return buffer;

}

static int DetectSshSoftwareSetup(DetectEngineCtx *de_ctx, Signature *s, const char *arg)

{

    if (SCDetectBufferSetActiveList(de_ctx, s, g_buffer_id) < 0)

        return -1;

    if (SCDetectSignatureSetAppProto(s, ALPROTO_SSH) < 0)

        return -1;

    return 0;

}

void DetectSshSoftwareRegister(void)

{

    sigmatch_table[DETECT_SSH_SOFTWARE].name = KEYWORD_NAME;

    sigmatch_table[DETECT_SSH_SOFTWARE].alias = KEYWORD_NAME_LEGACY;

    sigmatch_table[DETECT_SSH_SOFTWARE].desc = BUFFER_NAME " sticky buffer";

    sigmatch_table[DETECT_SSH_SOFTWARE].url = "/rules/" KEYWORD_DOC;

    sigmatch_table[DETECT_SSH_SOFTWARE].Setup = DetectSshSoftwareSetup;

    sigmatch_table[DETECT_SSH_SOFTWARE].flags |= SIGMATCH_INFO_STICKY_BUFFER | SIGMATCH_NOOPT;

    DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister,

            GetSshData, ALPROTO_SSH, SshStateBannerDone),

            DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOCLIENT, 2,

                    PrefilterGenericMpmRegister, GetSshData, ALPROTO_SSH, SshStateBannerDone),

            DetectAppLayerInspectEngineRegister(BUFFER_NAME, ALPROTO_SSH, SIG_FLAG_TOSERVER,

                    SshStateBannerDone, DetectEngineInspectBufferGeneric, GetSshData);

    DetectAppLayerInspectEngineRegister(BUFFER_NAME, ALPROTO_SSH, SIG_FLAG_TOCLIENT,

            SshStateBannerDone, DetectEngineInspectBufferGeneric, GetSshData);

    DetectBufferTypeSetDescriptionByName(BUFFER_NAME, BUFFER_DESC);

    g_buffer_id = DetectBufferTypeGetByName(BUFFER_NAME);

}