/* Copyright (c) 2008 Victor Julien <victor@inliniac.net> */

/* alert fastlog
 *
 * Logs alerts in a line based text format compatible to Snort's
 * alert_fast format.
 *
 * TODO
 * - Print the protocol as a string
 * - Support classifications
 * - Support priorities
 * - Support more than just IPv4/IPv4 TCP/UDP.
 * - Print [drop] as well if appropriate
 */

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#include "vips.h"
#include "debug.h"
#include "detect.h"
#include "flow.h"

#include "threadvars.h"
#include "tm-modules.h"

#include "util-unittest.h"

int AlertFastlog (ThreadVars *, Packet *, void *);
int AlertFastlogIPv4(ThreadVars *, Packet *, void *);
int AlertFastlogIPv6(ThreadVars *, Packet *, void *);
int AlertFastlogThreadInit(ThreadVars *, void **);
int AlertFastlogThreadDeinit(ThreadVars *, void *);

void TmModuleAlertFastlogRegister (void) {
    tmm_modules[TMM_ALERTFASTLOG].name = "AlertFastlog";
    tmm_modules[TMM_ALERTFASTLOG].Init = AlertFastlogThreadInit;
    tmm_modules[TMM_ALERTFASTLOG].Func = AlertFastlog;
    tmm_modules[TMM_ALERTFASTLOG].Deinit = AlertFastlogThreadDeinit;
    tmm_modules[TMM_ALERTFASTLOG].RegisterTests = NULL;
}

void TmModuleAlertFastlogIPv4Register (void) {
    tmm_modules[TMM_ALERTFASTLOG4].name = "AlertFastlogIPv4";
    tmm_modules[TMM_ALERTFASTLOG4].Init = AlertFastlogThreadInit;
    tmm_modules[TMM_ALERTFASTLOG4].Func = AlertFastlogIPv4;
    tmm_modules[TMM_ALERTFASTLOG4].Deinit = AlertFastlogThreadDeinit;
    tmm_modules[TMM_ALERTFASTLOG4].RegisterTests = NULL;
}

void TmModuleAlertFastlogIPv6Register (void) {
    tmm_modules[TMM_ALERTFASTLOG6].name = "AlertFastlogIPv6";
    tmm_modules[TMM_ALERTFASTLOG6].Init = AlertFastlogThreadInit;
    tmm_modules[TMM_ALERTFASTLOG6].Func = AlertFastlogIPv6;
    tmm_modules[TMM_ALERTFASTLOG6].Deinit = AlertFastlogThreadDeinit;
    tmm_modules[TMM_ALERTFASTLOG6].RegisterTests = NULL;
}

typedef struct _AlertFastlogThread {
    FILE *fp;
} AlertFastlogThread;

static void CreateTimeString (const struct timeval *ts, char *str, size_t size) {
    time_t time = ts->tv_sec;
    struct tm *t = gmtime(&time);
    u_int32_t sec = ts->tv_sec % 86400;

    snprintf(str, size, "%02d/%02d/%02d-%02d:%02d:%02d.%06u",
        t->tm_mon + 1, t->tm_mday, t->tm_year - 100,
        sec / 3600, (sec % 3600) / 60, sec % 60,
        (u_int32_t) ts->tv_usec);
}

int AlertFastlogIPv4(ThreadVars *tv, Packet *p, void *data)
{
    AlertFastlogThread *aft = (AlertFastlogThread *)data;
    int i;
    char timebuf[64];

    if (p->alerts.cnt == 0)
        return 0;

    CreateTimeString(&p->ts, timebuf, sizeof(timebuf));

    for (i = 0; i < p->alerts.cnt; i++) {
        PacketAlert *pa = &p->alerts.alerts[i];
        char srcip[16], dstip[16];

        inet_ntop(AF_INET, (const void *)GET_IPV4_SRC_ADDR_PTR(p), srcip, sizeof(srcip));
        inet_ntop(AF_INET, (const void *)GET_IPV4_DST_ADDR_PTR(p), dstip, sizeof(dstip));

        fprintf(aft->fp, "%s  [**] [%u:%u:%u] %s [**] [Classification: fixme] [Priority: 1] {%u} %s:%u -> %s:%u\n",
            timebuf, pa->gid, pa->sid, pa->rev, pa->msg, IPV4_GET_IPPROTO(p), srcip, p->sp, dstip, p->dp);
        fflush(aft->fp);
    }
    return 0;
}

int AlertFastlogIPv6(ThreadVars *tv, Packet *p, void *data)
{
    AlertFastlogThread *aft = (AlertFastlogThread *)data;
    int i;
    char timebuf[64];

    if (p->alerts.cnt == 0)
        return 0;

    CreateTimeString(&p->ts, timebuf, sizeof(timebuf));

    for (i = 0; i < p->alerts.cnt; i++) {
        PacketAlert *pa = &p->alerts.alerts[i];
        char srcip[46], dstip[46];

        inet_ntop(AF_INET6, (const void *)GET_IPV6_SRC_ADDR(p), srcip, sizeof(srcip));
        inet_ntop(AF_INET6, (const void *)GET_IPV6_DST_ADDR(p), dstip, sizeof(dstip));

        fprintf(aft->fp, "%s  [**] [%u:%u:%u] %s [**] [Classification: fixme] [Priority: 1] {%u} %s:%u -> %s:%u\n",
            timebuf, pa->gid, pa->sid, pa->rev, pa->msg, IPV6_GET_L4PROTO(p), srcip, p->sp, dstip, p->dp);
        fflush(aft->fp);
    }

    return 0;
}

int AlertFastlog (ThreadVars *tv, Packet *p, void *data)
{
    if (PKT_IS_IPV4(p)) {
        return(AlertFastlogIPv4(tv, p, data));
    } else if (PKT_IS_IPV6(p)) {
        return(AlertFastlogIPv6(tv, p, data));
    }

    return 0;
}

int AlertFastlogThreadInit(ThreadVars *t, void **data)
{
    AlertFastlogThread *aft = malloc(sizeof(AlertFastlogThread));
    if (aft == NULL) {
        return -1;
    }
    memset(aft, 0, sizeof(AlertFastlogThread));

    /* XXX */
    aft->fp = fopen("/var/log/eips/fast.log", "w");
    if (aft->fp == NULL) {
        return -1;
    }

    *data = (void *)aft;
    return 0;
}

int AlertFastlogThreadDeinit(ThreadVars *t, void *data)
{
    AlertFastlogThread *aft = (AlertFastlogThread *)data;
    if (aft == NULL) {
        return 0;
    }

    if (aft->fp != NULL)
        fclose(aft->fp);

    /* clear memory */
    memset(aft, 0, sizeof(AlertFastlogThread));

    free(aft);
    return 0;
}