/* Copyright (C) 2007-2021 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 Tom DeCanio <td@npulsetech.com>

 *

 * Implements SMTP JSON logging portion of the engine.

 */

#include "suricata-common.h"

#include "detect.h"

#include "pkt-var.h"

#include "conf.h"

#include "threads.h"

#include "threadvars.h"

#include "tm-threads.h"

#include "util-print.h"

#include "util-unittest.h"

#include "util-debug.h"

#include "output.h"

#include "app-layer-smtp.h"

#include "app-layer.h"

#include "app-layer-parser.h"

#include "util-privs.h"

#include "util-buffer.h"

#include "util-proto-name.h"

#include "util-logopenfile.h"

#include "util-time.h"

#include "output-json.h"

#include "output-json-smtp.h"

#include "output-json-email-common.h"

static void EveSmtpDataLogger(void *state, void *vtx, JsonBuilder *js)

{

    SMTPTransaction *tx = vtx;

    SMTPString *rcptto_str;

    if (((SMTPState *)state)->helo) {

        jb_set_string(js, "helo", (const char *)((SMTPState *)state)->helo);

    }

    if (tx->mail_from) {

        jb_set_string(js, "mail_from", (const char *)tx->mail_from);

    }

    if (!TAILQ_EMPTY(&tx->rcpt_to_list)) {

        jb_open_array(js, "rcpt_to");

        TAILQ_FOREACH(rcptto_str, &tx->rcpt_to_list, next) {

            jb_append_string(js, (char *)rcptto_str->str);

        }

        jb_close(js);

    }

}

static int JsonSmtpLogger(ThreadVars *tv, void *thread_data, const Packet *p, Flow *f, void *state, void *tx, uint64_t tx_id)

{

    SCEnter();

    JsonEmailLogThread *jhl = (JsonEmailLogThread *)thread_data;

    JsonBuilder *jb = CreateEveHeaderWithTxId(

            p, LOG_DIR_FLOW, "smtp", NULL, tx_id, jhl->emaillog_ctx->eve_ctx);

    if (unlikely(jb == NULL))

        return TM_ECODE_OK;

    jb_open_object(jb, "smtp");

    EveSmtpDataLogger(state, tx, jb);

    jb_close(jb);

    EveEmailLogJson(jhl, jb, p, f, state, tx, tx_id);

    OutputJsonBuilderBuffer(jb, jhl->ctx);

    jb_free(jb);

    SCReturnInt(TM_ECODE_OK);

}

bool EveSMTPAddMetadata(const Flow *f, uint64_t tx_id, JsonBuilder *js)

{

    SMTPState *smtp_state = (SMTPState *)FlowGetAppState(f);

    if (smtp_state) {

        SMTPTransaction *tx = AppLayerParserGetTx(IPPROTO_TCP, ALPROTO_SMTP, smtp_state, tx_id);

        if (tx) {

            EveSmtpDataLogger(smtp_state, tx, js);

            return true;

        }

    }

    return false;

}

static void OutputSmtpLogDeInitCtxSub(OutputCtx *output_ctx)

{

    SCLogDebug("cleaning up sub output_ctx %p", output_ctx);

    OutputJsonEmailCtx *email_ctx = output_ctx->data;

    if (email_ctx != NULL) {

        SCFree(email_ctx);

    }

    SCFree(output_ctx);

}

static OutputInitResult OutputSmtpLogInitSub(ConfNode *conf, OutputCtx *parent_ctx)

{

    OutputInitResult result = { NULL, false };

    OutputJsonCtx *ojc = parent_ctx->data;

    OutputJsonEmailCtx *email_ctx = SCCalloc(1, sizeof(OutputJsonEmailCtx));

    if (unlikely(email_ctx == NULL))

        return result;

    OutputCtx *output_ctx = SCCalloc(1, sizeof(OutputCtx));

    if (unlikely(output_ctx == NULL)) {

        SCFree(email_ctx);

        return result;

    }

    email_ctx->eve_ctx = ojc;

    OutputEmailInitConf(conf, email_ctx);

    output_ctx->data = email_ctx;

    output_ctx->DeInit = OutputSmtpLogDeInitCtxSub;

    /* enable the logger for the app layer */

    AppLayerParserRegisterLogger(IPPROTO_TCP, ALPROTO_SMTP);

    result.ctx = output_ctx;

    result.ok = true;

    return result;

}

static TmEcode JsonSmtpLogThreadInit(ThreadVars *t, const void *initdata, void **data)

{

    JsonEmailLogThread *aft = SCCalloc(1, sizeof(JsonEmailLogThread));

    if (unlikely(aft == NULL))

        return TM_ECODE_FAILED;

    if(initdata == NULL) {

        SCLogDebug("Error getting context for EveLogSMTP.  \"initdata\" argument NULL");

        goto error_exit;

    }

    /* Use the Output Context (file pointer and mutex) */

    aft->emaillog_ctx = ((OutputCtx *)initdata)->data;

    aft->ctx = CreateEveThreadCtx(t, aft->emaillog_ctx->eve_ctx);

    if (aft->ctx == NULL) {

        goto error_exit;

    }

    *data = (void *)aft;

    return TM_ECODE_OK;

error_exit:

    SCFree(aft);

    return TM_ECODE_FAILED;

}

static TmEcode JsonSmtpLogThreadDeinit(ThreadVars *t, void *data)

{

    JsonEmailLogThread *aft = (JsonEmailLogThread *)data;

    if (aft == NULL) {

        return TM_ECODE_OK;

    }

    FreeEveThreadCtx(aft->ctx);

    /* clear memory */

    memset(aft, 0, sizeof(JsonEmailLogThread));

    SCFree(aft);

    return TM_ECODE_OK;

}

void JsonSmtpLogRegister (void) {

    /* register as child of eve-log */

    OutputRegisterTxSubModule(LOGGER_JSON_TX, "eve-log", "JsonSmtpLog", "eve-log.smtp",

            OutputSmtpLogInitSub, ALPROTO_SMTP, JsonSmtpLogger, JsonSmtpLogThreadInit,

            JsonSmtpLogThreadDeinit, NULL);

}