/*
 *  Copyright (C) 2007 Tomasz Kojm <tkojm@clamav.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it 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
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *  MA 02110-1301, USA.
 */

#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>

#ifndef _WIN32
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#endif

#include "mirman.h"

#include "libclamav/cltypes.h"
#include "libclamav/clamav.h"

#include "shared/output.h"

#ifndef HAVE_GETADDRINFO
#ifndef AF_INET6
#define AF_INET6    0xbeef  /* foo */
#endif
#endif

#define IGNORE_LONG	3 * 86400
#define IGNORE_SHORT	1800

void mirman_free(struct mirdat *mdat)
{
    if(mdat && mdat->num) {
	free(mdat->mirtab);
	mdat->num = 0;
    }
}

int mirman_read(const char *file, struct mirdat *mdat, uint8_t active)
{
	struct mirdat_ip mip;
	int fd, bread;


    memset(mdat, 0, sizeof(struct mirdat));

    if(!(mdat->active = active))
	return 0;

    if((fd = open(file, O_RDONLY|O_BINARY)) == -1)
	return -1;

    while((bread = read(fd, &mip, sizeof(mip))) == sizeof(mip)) {
	mdat->mirtab = (struct mirdat_ip *) realloc(mdat->mirtab, (mdat->num + 1) * sizeof(mip));
	if(!mdat->mirtab) {
	    logg("!Can't allocate memory for mdat->mirtab\n");
	    mirman_free(mdat);
	    close(fd);
	    return -1;
	}
	memcpy(&mdat->mirtab[mdat->num], &mip, sizeof(mip));
	mdat->num++;
    }

    close(fd);

    if(bread) {
	logg("^Removing broken %s file.\n", file);
	unlink(file);
	mirman_free(mdat);
	return -1;
    }

    return 0;
}

int mirman_check(uint32_t *ip, int af, struct mirdat *mdat, struct mirdat_ip **md)
{
	unsigned int i, flevel = cl_retflevel();


    if(md)
	*md = NULL;

    if(!mdat->active)
	return 0;

    for(i = 0; i < mdat->num; i++) {

	if((af == AF_INET && mdat->mirtab[i].ip4 == *ip) || (af == AF_INET6 && !memcmp(mdat->mirtab[i].ip6, ip, 4 * sizeof(uint32_t)))) {

	    if(!mdat->mirtab[i].atime && !mdat->mirtab[i].ignore) {
		if(md)
		    *md = &mdat->mirtab[i];
		return 0;
	    }

	    if(mdat->dbflevel && (mdat->dbflevel > flevel) && (mdat->dbflevel - flevel > 3))
		if(time(NULL) - mdat->mirtab[i].atime < (mdat->dbflevel - flevel) * 3600)
		    return 2;

	    if(mdat->mirtab[i].ignore) {
		if(!mdat->mirtab[i].atime)
		    return 1;

		if(time(NULL) - mdat->mirtab[i].atime > IGNORE_LONG) {
		    mdat->mirtab[i].ignore = 0;
		    if(md)
			*md = &mdat->mirtab[i];
		    return 0;
		} else {
		    if(mdat->mirtab[i].ignore == 2 && (time(NULL) - mdat->mirtab[i].atime > IGNORE_SHORT)) {
			if(md)
			    *md = &mdat->mirtab[i];
			return 0;
		    }
		    return 1;
		}
	    }

	    if(md)
		*md = &mdat->mirtab[i];
	    return 0;
	}
    }

    return 0;
}

static int mirman_update_int(uint32_t *ip, int af, struct mirdat *mdat, uint8_t broken, int succ, int fail)
{
	unsigned int i, found = 0;


    if(!mdat->active)
	return 0;

    for(i = 0; i < mdat->num; i++) {
	if((af == AF_INET && mdat->mirtab[i].ip4 == *ip) || (af == AF_INET6 && !memcmp(mdat->mirtab[i].ip6, ip, 4 * sizeof(uint32_t)))) {
	    found = 1;
	    break;
	}
    }

    if(found) {
	mdat->mirtab[i].atime = 0; /* will be updated in mirman_write() */
	if(succ || fail) {
	    if((int) mdat->mirtab[i].fail + fail < 0)
		mdat->mirtab[i].fail = 0;
	    else
		mdat->mirtab[i].fail += fail;

	    if((int) mdat->mirtab[i].succ + succ < 0)
		mdat->mirtab[i].succ = 0;
	    else
		mdat->mirtab[i].succ += succ;
	} else {
	    if(broken)
		mdat->mirtab[i].fail++;
	    else
		mdat->mirtab[i].succ++;

	    if(broken == 2) {
		mdat->mirtab[i].ignore = 2;
	    } else {
		/*
		 * If the total number of failures is less than 3 then never
		 * mark a permanent failure, in other case use the real status.
		 */
		if(mdat->mirtab[i].fail < 3)
		    mdat->mirtab[i].ignore = 0;
		else
		    mdat->mirtab[i].ignore = broken;
	    }
	}
    } else {
	mdat->mirtab = (struct mirdat_ip *) realloc(mdat->mirtab, (mdat->num + 1) * sizeof(struct mirdat_ip));
	if(!mdat->mirtab) {
	    logg("!Can't allocate memory for new element in mdat->mirtab\n");
	    return -1;
	}
	if(af == AF_INET) {
	    mdat->mirtab[mdat->num].ip4 = *ip;
	} else {
	    mdat->mirtab[mdat->num].ip4 = 0;
	    memcpy(mdat->mirtab[mdat->num].ip6, ip, 4 * sizeof(uint32_t));
	}
	mdat->mirtab[mdat->num].atime = 0;
	mdat->mirtab[mdat->num].succ = (succ > 0) ? succ : 0;
	mdat->mirtab[mdat->num].fail = (fail > 0) ? fail : 0;
	mdat->mirtab[mdat->num].ignore = (broken == 2) ? 2 : 0;
	memset(&mdat->mirtab[mdat->num].res, 0xff, sizeof(mdat->mirtab[mdat->num].res));
	if(!succ && !fail) {
	    if(broken)
		mdat->mirtab[mdat->num].fail++;
	    else
		mdat->mirtab[mdat->num].succ++;
	}
	mdat->num++;
    }

    return 0;
}

int mirman_update(uint32_t *ip, int af, struct mirdat *mdat, uint8_t broken)
{
    return mirman_update_int(ip, af, mdat, broken, 0, 0);
}

int mirman_update_sf(uint32_t *ip, int af, struct mirdat *mdat, int succ, int fail)
{
    return mirman_update_int(ip, af, mdat, 0, succ, fail);
}

void mirman_list(const struct mirdat *mdat)
{
	unsigned int i;
	time_t tm;
	char ip[46];


    for(i = 0; i < mdat->num; i++) {
	printf("Mirror #%u\n", i + 1);
#ifdef HAVE_GETADDRINFO
	if(mdat->mirtab[i].ip4)
	    printf("IP: %s\n", inet_ntop(AF_INET, &mdat->mirtab[i].ip4, ip, sizeof(ip)));
	else
	    printf("IP: %s\n", inet_ntop(AF_INET6, mdat->mirtab[i].ip6, ip, sizeof(ip)));
#else
	if(mdat->mirtab[i].ip4)
	    printf("IP: %s\n", inet_ntoa(*(struct in_addr*) &mdat->mirtab[i].ip4));
#endif
	printf("Successes: %u\n", mdat->mirtab[i].succ);
	printf("Failures: %u\n", mdat->mirtab[i].fail);
	tm = mdat->mirtab[i].atime;
	printf("Last access: %s", ctime((const time_t *)&tm));
	printf("Ignore: %s\n", mdat->mirtab[i].ignore ? "Yes" : "No");
	if(i != mdat->num - 1)
	    printf("-------------------------------------\n");
    }
}

void mirman_whitelist(struct mirdat *mdat, unsigned int mode)
{
	unsigned int i;

    logg("*Whitelisting %s blacklisted mirrors\n", mode == 1 ? "all" : "short-term");
    for(i = 0; i < mdat->num; i++)
	if(mode == 1 || (mode == 2 && mdat->mirtab[i].ignore == 2))
	    mdat->mirtab[i].ignore = 0;
}

int mirman_write(const char *file, const char *dir, struct mirdat *mdat)
{
	int fd;
	unsigned int i;
	char path[512];

    snprintf(path, sizeof(path), "%s/%s", dir, file);
    path[sizeof(path) - 1] = 0;

    if(!mdat->num)
	return 0;

    if((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0600)) == -1) {
	logg("!Can't open %s for writing\n", path);
	return -1;
    }

    for(i = 0; i < mdat->num; i++)
	if(!mdat->mirtab[i].atime)
	    mdat->mirtab[i].atime = (uint32_t) time(NULL);

    if(write(fd, mdat->mirtab, mdat->num * sizeof(struct mirdat_ip)) == -1) {
	logg("!Can't write to %s\n", path);
	close(fd);
	return -1;
    }

    close(fd);
    return 0;
}
