/* Copyright (C) 2007-2013 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 JSON DNS logging portion of the engine.
 */

#include "suricata-common.h"
#include "debug.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 "util-mem.h"
#include "app-layer-parser.h"
#include "output.h"
#include "app-layer-dns-udp.h"
#include "app-layer.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-dns.h"

#ifdef HAVE_LIBJANSSON

/* we can do query logging as well, but it's disabled for now as the
 * TX id handling doesn't expect it */
#define QUERY 0

#define LOG_QUERIES    BIT_U64(0)
#define LOG_ANSWERS    BIT_U64(1)

#define LOG_A          BIT_U64(2)
#define LOG_NS         BIT_U64(3)
#define LOG_MD         BIT_U64(4)
#define LOG_MF         BIT_U64(5)
#define LOG_CNAME      BIT_U64(6)
#define LOG_SOA        BIT_U64(7)
#define LOG_MB         BIT_U64(8)
#define LOG_MG         BIT_U64(9)
#define LOG_MR         BIT_U64(10)
#define LOG_NULL       BIT_U64(11)
#define LOG_WKS        BIT_U64(12)
#define LOG_PTR        BIT_U64(13)
#define LOG_HINFO      BIT_U64(14)
#define LOG_MINFO      BIT_U64(15)
#define LOG_MX         BIT_U64(16)
#define LOG_TXT        BIT_U64(17)
#define LOG_RP         BIT_U64(18)
#define LOG_AFSDB      BIT_U64(19)
#define LOG_X25        BIT_U64(20)
#define LOG_ISDN       BIT_U64(21)
#define LOG_RT         BIT_U64(22)
#define LOG_NSAP       BIT_U64(23)
#define LOG_NSAPPTR    BIT_U64(24)
#define LOG_SIG        BIT_U64(25)
#define LOG_KEY        BIT_U64(26)
#define LOG_PX         BIT_U64(27)
#define LOG_GPOS       BIT_U64(28)
#define LOG_AAAA       BIT_U64(29)
#define LOG_LOC        BIT_U64(30)
#define LOG_NXT        BIT_U64(31)
#define LOG_SRV        BIT_U64(32)
#define LOG_ATMA       BIT_U64(33)
#define LOG_NAPTR      BIT_U64(34)
#define LOG_KX         BIT_U64(35)
#define LOG_CERT       BIT_U64(36)
#define LOG_A6         BIT_U64(37)
#define LOG_DNAME      BIT_U64(38)
#define LOG_OPT        BIT_U64(39)
#define LOG_APL        BIT_U64(40)
#define LOG_DS         BIT_U64(41)
#define LOG_SSHFP      BIT_U64(42)
#define LOG_IPSECKEY   BIT_U64(43)
#define LOG_RRSIG      BIT_U64(44)
#define LOG_NSEC       BIT_U64(45)
#define LOG_DNSKEY     BIT_U64(46)
#define LOG_DHCID      BIT_U64(47)
#define LOG_NSEC3      BIT_U64(48)
#define LOG_NSEC3PARAM BIT_U64(49)
#define LOG_TLSA       BIT_U64(50)
#define LOG_HIP        BIT_U64(51)
#define LOG_CDS        BIT_U64(52)
#define LOG_CDNSKEY    BIT_U64(53)
#define LOG_SPF        BIT_U64(54)
#define LOG_TKEY       BIT_U64(55)
#define LOG_TSIG       BIT_U64(56)
#define LOG_MAILA      BIT_U64(57)
#define LOG_ANY        BIT_U64(58)
#define LOG_URI        BIT_U64(59)

#define LOG_ALL_RRTYPES (~(uint64_t)(LOG_QUERIES|LOG_ANSWERS))

typedef enum {
    DNS_RRTYPE_A = 0,
    DNS_RRTYPE_NS,
    DNS_RRTYPE_MD,
    DNS_RRTYPE_MF,
    DNS_RRTYPE_CNAME,
    DNS_RRTYPE_SOA,
    DNS_RRTYPE_MB,
    DNS_RRTYPE_MG,
    DNS_RRTYPE_MR,
    DNS_RRTYPE_NULL,
    DNS_RRTYPE_WKS,
    DNS_RRTYPE_PTR,
    DNS_RRTYPE_HINFO,
    DNS_RRTYPE_MINFO,
    DNS_RRTYPE_MX,
    DNS_RRTYPE_TXT,
    DNS_RRTYPE_RP,
    DNS_RRTYPE_AFSDB,
    DNS_RRTYPE_X25,
    DNS_RRTYPE_ISDN,
    DNS_RRTYPE_RT,
    DNS_RRTYPE_NSAP,
    DNS_RRTYPE_NSAPPTR,
    DNS_RRTYPE_SIG,
    DNS_RRTYPE_KEY,
    DNS_RRTYPE_PX,
    DNS_RRTYPE_GPOS,
    DNS_RRTYPE_AAAA,
    DNS_RRTYPE_LOC,
    DNS_RRTYPE_NXT,
    DNS_RRTYPE_SRV,
    DNS_RRTYPE_ATMA,
    DNS_RRTYPE_NAPTR,
    DNS_RRTYPE_KX,
    DNS_RRTYPE_CERT,
    DNS_RRTYPE_A6,
    DNS_RRTYPE_DNAME,
    DNS_RRTYPE_OPT,
    DNS_RRTYPE_APL,
    DNS_RRTYPE_DS,
    DNS_RRTYPE_SSHFP,
    DNS_RRTYPE_IPSECKEY,
    DNS_RRTYPE_RRSIG,
    DNS_RRTYPE_NSEC,
    DNS_RRTYPE_DNSKEY,
    DNS_RRTYPE_DHCID,
    DNS_RRTYPE_NSEC3,
    DNS_RRTYPE_NSEC3PARAM,
    DNS_RRTYPE_TLSA,
    DNS_RRTYPE_HIP,
    DNS_RRTYPE_CDS,
    DNS_RRTYPE_CDNSKEY,
    DNS_RRTYPE_SPF,
    DNS_RRTYPE_TKEY,
    DNS_RRTYPE_TSIG,
    DNS_RRTYPE_MAILA,
    DNS_RRTYPE_ANY,
    DNS_RRTYPE_URI
} DnsRRTypes;

static struct {
    const char *config_rrtype;
    uint64_t flags;
} dns_rrtype_fields[] = {
   { "a", LOG_A },
   { "ns", LOG_NS },
   { "md", LOG_MD },
   { "mf", LOG_MF },
   { "cname", LOG_CNAME },
   { "soa", LOG_SOA },
   { "mb", LOG_MB },
   { "mg", LOG_MG },
   { "mr", LOG_MR },
   { "null", LOG_NULL },
   { "wks", LOG_WKS },
   { "ptr", LOG_PTR },
   { "hinfo", LOG_HINFO },
   { "minfo", LOG_MINFO },
   { "mx", LOG_MX },
   { "txt", LOG_TXT },
   { "rp", LOG_RP },
   { "afsdb", LOG_AFSDB },
   { "x25", LOG_X25 },
   { "isdn", LOG_ISDN },
   { "rt", LOG_RT },
   { "nsap", LOG_NSAP },
   { "nsapptr", LOG_NSAPPTR },
   { "sig", LOG_SIG },
   { "key", LOG_KEY },
   { "px", LOG_PX },
   { "gpos", LOG_GPOS },
   { "aaaa", LOG_AAAA },
   { "loc", LOG_LOC },
   { "nxt", LOG_NXT },
   { "srv", LOG_SRV },
   { "atma", LOG_ATMA },
   { "naptr", LOG_NAPTR },
   { "kx", LOG_KX },
   { "cert", LOG_CERT },
   { "a6", LOG_A6 },
   { "dname", LOG_DNAME },
   { "opt", LOG_OPT },
   { "apl", LOG_APL },
   { "ds", LOG_DS },
   { "sshfp", LOG_SSHFP },
   { "ipseckey", LOG_IPSECKEY },
   { "rrsig", LOG_RRSIG },
   { "nsec", LOG_NSEC },
   { "dnskey", LOG_DNSKEY },
   { "dhcid", LOG_DHCID },
   { "nsec3", LOG_NSEC3 },
   { "nsec3param", LOG_NSEC3PARAM },
   { "tlsa", LOG_TLSA },
   { "hip", LOG_HIP },
   { "cds", LOG_CDS },
   { "cdnskey", LOG_CDNSKEY },
   { "spf", LOG_SPF },
   { "tkey", LOG_TKEY },
   { "tsig", LOG_TSIG },
   { "maila", LOG_MAILA },
   { "any", LOG_ANY },
   { "uri", LOG_URI }
};

typedef struct LogDnsFileCtx_ {
    LogFileCtx *file_ctx;
    uint64_t flags; /** Store mode */
} LogDnsFileCtx;

typedef struct LogDnsLogThread_ {
    LogDnsFileCtx *dnslog_ctx;
    /** LogFileCtx has the pointer to the file and a mutex to allow multithreading */
    uint32_t dns_cnt;

    MemBuffer *buffer;
} LogDnsLogThread;

static int DNSRRTypeEnabled(uint16_t type, uint64_t flags)
{
    if (likely(flags == ~0UL)) {
        return 1;
    }

    switch (type) {
        case DNS_RECORD_TYPE_A:
            return ((flags & LOG_A) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NS:
            return ((flags & LOG_NS) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MD:
            return ((flags & LOG_MD) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MF:
            return ((flags & LOG_MF) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_CNAME:
            return ((flags & LOG_CNAME) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_SOA:
            return ((flags & LOG_SOA) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MB:
            return ((flags & LOG_MB) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MG:
            return ((flags & LOG_MG) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MR:
            return ((flags & LOG_MR) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NULL:
            return ((flags & LOG_NULL) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_WKS:
            return ((flags & LOG_WKS) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_PTR:
            return ((flags & LOG_PTR) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_HINFO:
            return ((flags & LOG_HINFO) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MINFO:
            return ((flags & LOG_MINFO) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MX:
            return ((flags & LOG_MX) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_TXT:
            return ((flags & LOG_TXT) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_RP:
            return ((flags & LOG_RP) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_AFSDB:
            return ((flags & LOG_AFSDB) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_X25:
            return ((flags & LOG_X25) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_ISDN:
            return ((flags & LOG_ISDN) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_RT:
            return ((flags & LOG_RT) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NSAP:
            return ((flags & LOG_NSAP) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NSAPPTR:
            return ((flags & LOG_NSAPPTR) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_SIG:
            return ((flags & LOG_SIG) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_KEY:
            return ((flags & LOG_KEY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_PX:
            return ((flags & LOG_PX) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_GPOS:
            return ((flags & LOG_GPOS) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_AAAA:
            return ((flags & LOG_AAAA) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_LOC:
            return ((flags & LOG_LOC) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NXT:
            return ((flags & LOG_NXT) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_SRV:
            return ((flags & LOG_SRV) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_ATMA:
            return ((flags & LOG_ATMA) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NAPTR:
            return ((flags & LOG_NAPTR) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_KX:
            return ((flags & LOG_KX) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_CERT:
            return ((flags & LOG_CERT) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_A6:
            return ((flags & LOG_A6) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_DNAME:
            return ((flags & LOG_DNAME) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_OPT:
            return ((flags & LOG_OPT) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_APL:
            return ((flags & LOG_APL) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_DS:
            return ((flags & LOG_DS) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_SSHFP:
            return ((flags & LOG_SSHFP) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_IPSECKEY:
            return ((flags & LOG_IPSECKEY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_RRSIG:
            return ((flags & LOG_RRSIG) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NSEC:
            return ((flags & LOG_NSEC) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_DNSKEY:
            return ((flags & LOG_DNSKEY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_DHCID:
            return ((flags & LOG_DHCID) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NSEC3:
            return ((flags & LOG_NSEC3) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_NSEC3PARAM:
            return ((flags & LOG_NSEC3PARAM) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_TLSA:
            return ((flags & LOG_TLSA) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_HIP:
            return ((flags & LOG_HIP) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_CDS:
            return ((flags & LOG_CDS) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_CDNSKEY:
            return ((flags & LOG_CDNSKEY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_SPF:
            return ((flags & LOG_SPF) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_TKEY:
            return ((flags & LOG_TKEY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_TSIG:
            return ((flags & LOG_TSIG) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_MAILA:
            return ((flags & LOG_MAILA) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_ANY:
            return ((flags & LOG_ANY) != 0) ? 1 : 0;
        case DNS_RECORD_TYPE_URI:
            return ((flags & LOG_URI) != 0) ? 1 : 0;
        default:
            return 0;
    }
}

static void LogQuery(LogDnsLogThread *aft, json_t *js, DNSTransaction *tx,
        uint64_t tx_id, DNSQueryEntry *entry) __attribute__((nonnull));

static void LogQuery(LogDnsLogThread *aft, json_t *js, DNSTransaction *tx,
        uint64_t tx_id, DNSQueryEntry *entry)
{
    SCLogDebug("got a DNS request and now logging !!");

    if (!DNSRRTypeEnabled(entry->type, aft->dnslog_ctx->flags)) {
        return;
    }

    json_t *djs = json_object();
    if (djs == NULL) {
        return;
    }

    /* reset */
    MemBufferReset(aft->buffer);

    /* type */
    json_object_set_new(djs, "type", json_string("query"));

    /* id */
    json_object_set_new(djs, "id", json_integer(tx->tx_id));

    /* query */
    char *c;
    c = BytesToString((uint8_t *)((uint8_t *)entry + sizeof(DNSQueryEntry)), entry->len);
    if (c != NULL) {
        json_object_set_new(djs, "rrname", json_string(c));
        SCFree(c);
    }

    /* name */
    char record[16] = "";
    DNSCreateTypeString(entry->type, record, sizeof(record));
    json_object_set_new(djs, "rrtype", json_string(record));

    /* tx id (tx counter) */
    json_object_set_new(djs, "tx_id", json_integer(tx_id));

    /* dns */
    json_object_set_new(js, "dns", djs);
    OutputJSONBuffer(js, aft->dnslog_ctx->file_ctx, &aft->buffer);
    json_object_del(js, "dns");
}

static void OutputAnswer(LogDnsLogThread *aft, json_t *djs,
        DNSTransaction *tx, DNSAnswerEntry *entry) __attribute__((nonnull));

static void OutputAnswer(LogDnsLogThread *aft, json_t *djs,
        DNSTransaction *tx, DNSAnswerEntry *entry)
{
    if (!DNSRRTypeEnabled(entry->type, aft->dnslog_ctx->flags)) {
        return;
    }

    json_t *js = json_object();
    if (js == NULL)
        return;

    /* type */
    json_object_set_new(js, "type", json_string("answer"));

    /* id */
    json_object_set_new(js, "id", json_integer(tx->tx_id));

    /* rcode */
    char rcode[16] = "";
    DNSCreateRcodeString(tx->rcode, rcode, sizeof(rcode));
    json_object_set_new(js, "rcode", json_string(rcode));

    /* query */
    if (entry->fqdn_len > 0) {
        char *c;
        c = BytesToString((uint8_t *)((uint8_t *)entry + sizeof(DNSAnswerEntry)),
                entry->fqdn_len);
        if (c != NULL) {
            json_object_set_new(js, "rrname", json_string(c));
            SCFree(c);
        }
    }

    /* name */
    char record[16] = "";
    DNSCreateTypeString(entry->type, record, sizeof(record));
    json_object_set_new(js, "rrtype", json_string(record));

    /* ttl */
    json_object_set_new(js, "ttl", json_integer(entry->ttl));

    uint8_t *ptr = (uint8_t *)((uint8_t *)entry + sizeof(DNSAnswerEntry)+ entry->fqdn_len);
    if (entry->type == DNS_RECORD_TYPE_A && entry->data_len == 4) {
        char a[16] = "";
        PrintInet(AF_INET, (const void *)ptr, a, sizeof(a));
        json_object_set_new(js, "rdata", json_string(a));
    } else if (entry->type == DNS_RECORD_TYPE_AAAA && entry->data_len == 16) {
        char a[46] = "";
        PrintInet(AF_INET6, (const void *)ptr, a, sizeof(a));
        json_object_set_new(js, "rdata", json_string(a));
    } else if (entry->data_len == 0) {
        json_object_set_new(js, "rdata", json_string(""));
    } else if (entry->type == DNS_RECORD_TYPE_TXT || entry->type == DNS_RECORD_TYPE_CNAME ||
            entry->type == DNS_RECORD_TYPE_MX || entry->type == DNS_RECORD_TYPE_PTR ||
            entry->type == DNS_RECORD_TYPE_NS) {
        if (entry->data_len != 0) {
            char buffer[256] = "";
            uint16_t copy_len = entry->data_len < (sizeof(buffer) - 1) ?
                entry->data_len : sizeof(buffer) - 1;
            memcpy(buffer, ptr, copy_len);
            buffer[copy_len] = '\0';
            json_object_set_new(js, "rdata", json_string(buffer));
        } else {
            json_object_set_new(js, "rdata", json_string(""));
        }
    } else if (entry->type == DNS_RECORD_TYPE_SSHFP) {
        if (entry->data_len > 2) {
            /* get algo and type */
            uint8_t algo = *ptr;
            uint8_t fptype = *(ptr+1);

            /* turn fp raw buffer into a nice :-separate hex string */
            uint16_t fp_len = (entry->data_len - 2);
            uint8_t *dptr = ptr+2;

            /* c-string for ':' separated hex and trailing \0. */
            uint32_t output_len = fp_len * 3 + 1;
            char hexstring[output_len];
            memset(hexstring, 0x00, output_len);

            uint16_t x;
            for (x = 0; x < fp_len; x++) {
                char one[4];
                snprintf(one, sizeof(one), x == fp_len - 1 ? "%02x" : "%02x:", dptr[x]);
                strlcat(hexstring, one, output_len);
            }

            /* wrap the whole thing in it's own structure */
            json_t *hjs = json_object();
            if (hjs != NULL) {
                json_object_set_new(hjs, "fingerprint", json_string(hexstring));
                json_object_set_new(hjs, "algo", json_integer(algo));
                json_object_set_new(hjs, "type", json_integer(fptype));

                json_object_set_new(js, "sshfp", hjs);
            }
        }
    }

    /* reset */
    MemBufferReset(aft->buffer);
    json_object_set_new(djs, "dns", js);
    OutputJSONBuffer(djs, aft->dnslog_ctx->file_ctx, &aft->buffer);
    json_object_del(djs, "dns");

    return;
}

static void OutputFailure(LogDnsLogThread *aft, json_t *djs,
        DNSTransaction *tx, DNSQueryEntry *entry) __attribute__((nonnull));

static void OutputFailure(LogDnsLogThread *aft, json_t *djs,
        DNSTransaction *tx, DNSQueryEntry *entry)
{
    if (!DNSRRTypeEnabled(entry->type, aft->dnslog_ctx->flags)) {
        return;
    }

    json_t *js = json_object();
    if (js == NULL)
        return;

    /* type */
    json_object_set_new(js, "type", json_string("answer"));

    /* id */
    json_object_set_new(js, "id", json_integer(tx->tx_id));

    /* rcode */
    char rcode[16] = "";
    DNSCreateRcodeString(tx->rcode, rcode, sizeof(rcode));
    json_object_set_new(js, "rcode", json_string(rcode));

    /* no answer RRs, use query for rname */
    char *c;
    c = BytesToString((uint8_t *)((uint8_t *)entry + sizeof(DNSQueryEntry)), entry->len);
    if (c != NULL) {
        json_object_set_new(js, "rrname", json_string(c));
        SCFree(c);
    }

    /* reset */
    MemBufferReset(aft->buffer);
    json_object_set_new(djs, "dns", js);
    OutputJSONBuffer(djs, aft->dnslog_ctx->file_ctx, &aft->buffer);
    json_object_del(djs, "dns");

    return;
}

static void LogAnswers(LogDnsLogThread *aft, json_t *js, DNSTransaction *tx, uint64_t tx_id)
{

    SCLogDebug("got a DNS response and now logging !!");

    /* rcode != noerror */
    if (tx->rcode) {
        /* Most DNS servers do not support multiple queries because
         * the rcode in response is not per-query.  Multiple queries
         * are likely to lead to FORMERR, so log this. */
        DNSQueryEntry *query = NULL;
        TAILQ_FOREACH(query, &tx->query_list, next) {
            OutputFailure(aft, js, tx, query);
        }
    }

    DNSAnswerEntry *entry = NULL;
    TAILQ_FOREACH(entry, &tx->answer_list, next) {
        OutputAnswer(aft, js, tx, entry);
    }

    entry = NULL;
    TAILQ_FOREACH(entry, &tx->authority_list, next) {
        OutputAnswer(aft, js, tx, entry);
    }

}

static int JsonDnsLoggerToServer(ThreadVars *tv, void *thread_data,
    const Packet *p, Flow *f, void *alstate, void *txptr, uint64_t tx_id)
{
    SCEnter();

    LogDnsLogThread *td = (LogDnsLogThread *)thread_data;
    LogDnsFileCtx *dnslog_ctx = td->dnslog_ctx;
    DNSTransaction *tx = txptr;
    json_t *js;

    if (likely(dnslog_ctx->flags & LOG_QUERIES) != 0) {
        DNSQueryEntry *query = NULL;
        TAILQ_FOREACH(query, &tx->query_list, next) {
            js = CreateJSONHeader((Packet *)p, 1, "dns");
            if (unlikely(js == NULL))
                return TM_ECODE_OK;

            LogQuery(td, js, tx, tx_id, query);

            json_decref(js);
        }
    }

    SCReturnInt(TM_ECODE_OK);
}

static int JsonDnsLoggerToClient(ThreadVars *tv, void *thread_data,
    const Packet *p, Flow *f, void *alstate, void *txptr, uint64_t tx_id)
{
    SCEnter();

    LogDnsLogThread *td = (LogDnsLogThread *)thread_data;
    LogDnsFileCtx *dnslog_ctx = td->dnslog_ctx;
    DNSTransaction *tx = txptr;
    json_t *js;

    if (likely(dnslog_ctx->flags & LOG_ANSWERS) != 0) {
        js = CreateJSONHeader((Packet *)p, 0, "dns");
        if (unlikely(js == NULL))
            return TM_ECODE_OK;

        LogAnswers(td, js, tx, tx_id);

        json_decref(js);
    }

    SCReturnInt(TM_ECODE_OK);
}

#define OUTPUT_BUFFER_SIZE 65536
static TmEcode LogDnsLogThreadInit(ThreadVars *t, const void *initdata, void **data)
{
    LogDnsLogThread *aft = SCMalloc(sizeof(LogDnsLogThread));
    if (unlikely(aft == NULL))
        return TM_ECODE_FAILED;
    memset(aft, 0, sizeof(LogDnsLogThread));

    if(initdata == NULL)
    {
        SCLogDebug("Error getting context for EveLogDNS.  \"initdata\" argument NULL");
        SCFree(aft);
        return TM_ECODE_FAILED;
    }

    aft->buffer = MemBufferCreateNew(OUTPUT_BUFFER_SIZE);
    if (aft->buffer == NULL) {
        SCFree(aft);
        return TM_ECODE_FAILED;
    }

    /* Use the Ouptut Context (file pointer and mutex) */
    aft->dnslog_ctx= ((OutputCtx *)initdata)->data;

    *data = (void *)aft;
    return TM_ECODE_OK;
}

static TmEcode LogDnsLogThreadDeinit(ThreadVars *t, void *data)
{
    LogDnsLogThread *aft = (LogDnsLogThread *)data;
    if (aft == NULL) {
        return TM_ECODE_OK;
    }

    MemBufferFree(aft->buffer);
    /* clear memory */
    memset(aft, 0, sizeof(LogDnsLogThread));

    SCFree(aft);
    return TM_ECODE_OK;
}

static void LogDnsLogDeInitCtx(OutputCtx *output_ctx)
{
    LogDnsFileCtx *dnslog_ctx = (LogDnsFileCtx *)output_ctx->data;
    LogFileFreeCtx(dnslog_ctx->file_ctx);
    SCFree(dnslog_ctx);
    SCFree(output_ctx);
}

static void LogDnsLogDeInitCtxSub(OutputCtx *output_ctx)
{
    SCLogDebug("cleaning up sub output_ctx %p", output_ctx);
    LogDnsFileCtx *dnslog_ctx = (LogDnsFileCtx *)output_ctx->data;
    SCFree(dnslog_ctx);
    SCFree(output_ctx);
}

static void JsonDnsLogInitFilters(LogDnsFileCtx *dnslog_ctx, ConfNode *conf)
{
    dnslog_ctx->flags = ~0UL;

    if (conf) {
        const char *query = ConfNodeLookupChildValue(conf, "query");
        if (query != NULL) {
            if (ConfValIsTrue(query)) {
                dnslog_ctx->flags |= LOG_QUERIES;
            } else {
                dnslog_ctx->flags &= ~LOG_QUERIES;
            }
        }
        const char *response = ConfNodeLookupChildValue(conf, "answer");
        if (response != NULL) {
            if (ConfValIsTrue(response)) {
                dnslog_ctx->flags |= LOG_ANSWERS;
            } else {
                dnslog_ctx->flags &= ~LOG_ANSWERS;
            }
        }
        ConfNode *custom;
        if ((custom = ConfNodeLookupChild(conf, "custom")) != NULL) {
            dnslog_ctx->flags &= ~LOG_ALL_RRTYPES;
            ConfNode *field;
            TAILQ_FOREACH(field, &custom->head, next)
            {
                if (field != NULL)
                {
                    DnsRRTypes f;
                    for (f = DNS_RRTYPE_A; f < DNS_RRTYPE_TXT; f++)
                    {
                        if (strcasecmp(dns_rrtype_fields[f].config_rrtype,
                                       field->val) == 0)
                        {
                            dnslog_ctx->flags |= dns_rrtype_fields[f].flags;
                            break;
                        }
                    }
                }
            }
        }
    }
}

static OutputCtx *JsonDnsLogInitCtxSub(ConfNode *conf, OutputCtx *parent_ctx)
{
    OutputJsonCtx *ojc = parent_ctx->data;

    LogDnsFileCtx *dnslog_ctx = SCMalloc(sizeof(LogDnsFileCtx));
    if (unlikely(dnslog_ctx == NULL)) {
        return NULL;
    }
    memset(dnslog_ctx, 0x00, sizeof(LogDnsFileCtx));

    dnslog_ctx->file_ctx = ojc->file_ctx;

    OutputCtx *output_ctx = SCCalloc(1, sizeof(OutputCtx));
    if (unlikely(output_ctx == NULL)) {
        SCFree(dnslog_ctx);
        return NULL;
    }

    output_ctx->data = dnslog_ctx;
    output_ctx->DeInit = LogDnsLogDeInitCtxSub;

    JsonDnsLogInitFilters(dnslog_ctx, conf);

    SCLogDebug("DNS log sub-module initialized");

    AppLayerParserRegisterLogger(IPPROTO_UDP, ALPROTO_DNS);
    AppLayerParserRegisterLogger(IPPROTO_TCP, ALPROTO_DNS);

    return output_ctx;
}

#define DEFAULT_LOG_FILENAME "dns.json"
/** \brief Create a new dns log LogFileCtx.
 *  \param conf Pointer to ConfNode containing this loggers configuration.
 *  \return NULL if failure, LogFileCtx* to the file_ctx if succesful
 * */
static OutputCtx *JsonDnsLogInitCtx(ConfNode *conf)
{
    LogFileCtx *file_ctx = LogFileNewCtx();

    if(file_ctx == NULL) {
        SCLogError(SC_ERR_DNS_LOG_GENERIC, "couldn't create new file_ctx");
        return NULL;
    }

    if (SCConfLogOpenGeneric(conf, file_ctx, DEFAULT_LOG_FILENAME, 1) < 0) {
        LogFileFreeCtx(file_ctx);
        return NULL;
    }

    LogDnsFileCtx *dnslog_ctx = SCMalloc(sizeof(LogDnsFileCtx));
    if (unlikely(dnslog_ctx == NULL)) {
        LogFileFreeCtx(file_ctx);
        return NULL;
    }
    memset(dnslog_ctx, 0x00, sizeof(LogDnsFileCtx));

    dnslog_ctx->file_ctx = file_ctx;

    OutputCtx *output_ctx = SCCalloc(1, sizeof(OutputCtx));
    if (unlikely(output_ctx == NULL)) {
        LogFileFreeCtx(file_ctx);
        SCFree(dnslog_ctx);
        return NULL;
    }

    output_ctx->data = dnslog_ctx;
    output_ctx->DeInit = LogDnsLogDeInitCtx;

    JsonDnsLogInitFilters(dnslog_ctx, conf);

    SCLogDebug("DNS log output initialized");

    AppLayerParserRegisterLogger(IPPROTO_UDP, ALPROTO_DNS);
    AppLayerParserRegisterLogger(IPPROTO_TCP, ALPROTO_DNS);

    return output_ctx;
}


#define MODULE_NAME "JsonDnsLog"
void JsonDnsLogRegister (void)
{
    /* Logger for requests. */
    OutputRegisterTxModuleWithProgress(LOGGER_JSON_DNS, MODULE_NAME,
        "dns-json-log", JsonDnsLogInitCtx, ALPROTO_DNS, JsonDnsLoggerToServer,
        0, 1, LogDnsLogThreadInit, LogDnsLogThreadDeinit, NULL);

    /* Logger for replies. */
    OutputRegisterTxModuleWithProgress(LOGGER_JSON_DNS, MODULE_NAME,
        "dns-json-log", JsonDnsLogInitCtx, ALPROTO_DNS, JsonDnsLoggerToClient,
        1, 1, LogDnsLogThreadInit, LogDnsLogThreadDeinit, NULL);

    /* Sub-logger for requests. */
    OutputRegisterTxSubModuleWithProgress(LOGGER_JSON_DNS, "eve-log",
        MODULE_NAME, "eve-log.dns", JsonDnsLogInitCtxSub, ALPROTO_DNS,
        JsonDnsLoggerToServer, 0, 1, LogDnsLogThreadInit,
        LogDnsLogThreadDeinit, NULL);

    /* Sub-logger for replies. */
    OutputRegisterTxSubModuleWithProgress(LOGGER_JSON_DNS, "eve-log",
        MODULE_NAME, "eve-log.dns", JsonDnsLogInitCtxSub, ALPROTO_DNS,
        JsonDnsLoggerToClient, 1, 1, LogDnsLogThreadInit, LogDnsLogThreadDeinit,
        NULL);
}

#else

void JsonDnsLogRegister (void)
{
}

#endif