/*
dnsdcc.c - MessageWall DNS DCC definitions
Copyright (C) 2002 Ian Gulliver

This program is free software; you can redistribute it and/or modify
it under the terms of version 2 of the GNU General Public License 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <time.h>
#include <firestring.h>
#include <firedns.h>
#include "messagewall.h"
#include "md5.h"
#include "mime.h"
#include "smtp.h"
#include "dnsdcc.h"

static const char tagstring[] = "$Id: dnsdcc.c,v 1.20 2002/07/15 17:48:26 ian Exp $";

char *dnsdcc_checksum_aa(struct firestring_estr_t *chunk) {
	/*
	 * this is a standard boring md5
	 */
	static char ret[33];
	md5_state_t state;
	md5_byte_t digest[16];
	int i;


	md5_init(&state);
	md5_append(&state, (unsigned char *) chunk->s, chunk->l);
	md5_finish(&state, digest);

	/*
	 * we know the maximum size of the object we're printing (1 byte), so this sprintf is safe
         */
	for (i = 0; i < 16; i++) 
		sprintf(ret + i * 2, "%02x", digest[i]); /* ITS4: ignore sprintf */

	return ret;
}

char *dnsdcc_checksum_ba(struct firestring_estr_t *chunk) {
	/*
	 * mad crazy linguistic "the" hook checksum
	 */
	static struct firestring_estr_t line = {0};
	int i = 0;
	int words = 0;

	if (line.a == 0)
		firestring_estr_alloc(&line,DNSDCC_BA_MAXLEN);

	line.l = 0;
	while (words < 10) {
		i = firestring_estr_stristr(chunk,"the",i);
		if (i == -1)
			break;
		i += 3;
		if (chunk->l <= i)
			break;
		if (strchr(DNSDCC_WHITESPACE,chunk->s[i]) == NULL)
			continue;
		while (strchr(DNSDCC_WHITESPACE,chunk->s[i]) != NULL) {
			i++;
			if (chunk->l <= i)
				goto dnsdcc_ba_out;
		}
		while (strchr(DNSDCC_WHITESPACE,chunk->s[i]) == NULL) {
			/* 
			 * check for space in line
			 */
			if (line.l >= line.a - 1)
				goto dnsdcc_ba_out;

			/*
			 * check for end of source
			 */
			if (i == chunk->l - 1)
				goto dnsdcc_ba_out;

			line.s[line.l++] = tolower(chunk->s[i]);
			i++;
		}
		line.s[line.l++] = ' ';
		words++;
	}

dnsdcc_ba_out:

	if (words < 5)
		return NULL;

	return dnsdcc_checksum_aa(&line);
}

int dnsdcc_clear_queries(int client) {
	time(&clients[client].dnsdcc_send);
	clients[client].resent_dnsdcc = 0;
	clients[client].num_parts = 0;

	return 0;
}

int dnsdcc_send_queries(int client, int part, char *(*check)(struct firestring_estr_t *), struct firestring_estr_t *chunk) {
	struct messagewall_dnsdcc_global_t *dnsdcc;
	char *res;
	char query[256];

	clients[client].resent_dnsdcc = 0;

	res = check(chunk);
	if (res == NULL)
		return 0;

	dnsdcc = dnsdcc_head;
	while (dnsdcc != NULL) {
		if (dnsdcc->check != check) {
			dnsdcc = dnsdcc->next;
			continue;
		}
		firestring_snprintf(query,256,"%s.%e",res,&dnsdcc->dnsdcc);
		clients[client].dnsdcc_fd[part][dnsdcc->i] = firedns_gettxt(query);
		dnsdcc = dnsdcc->next;
	}
	clients[client].num_parts = max(clients[client].num_parts,part);

	return 0;
}

int dnsdcc_resend_queries(int client) {
	struct messagewall_dnsdcc_global_t *dnsdcc;
	char query[256];
	int i;
	
	dnsdcc = dnsdcc_head;
	while (dnsdcc != NULL) {
		for (i = 0; i < clients[client].num_parts; i++)
			if (clients[client].dnsdcc_fd[i][dnsdcc->i] >= 0) {
				firedns_getresult(clients[client].dnsdcc_fd[i][dnsdcc->i]);
				firestring_snprintf(query,256,"%s.%s",dnsdcc->check(&clients[client].parts[i].message.body),&dnsdcc->dnsdcc);
				clients[client].dnsdcc_fd[i][dnsdcc->i] = firedns_gettxt(query);
			}
		dnsdcc = dnsdcc->next;
	}

	return 0;
}

int dnsdcc_response(int client, int part, int dnsdcc) {
	char *ret;

	ret = firedns_getresult(clients[client].dnsdcc_fd[part][dnsdcc]);
	if (ret == NULL)
		clients[client].dnsdcc_fd[part][dnsdcc] = -1;
	else
		clients[client].dnsdcc_fd[part][dnsdcc] = -2;

	return 0;
}

int dnsdcc_check_profile(int client, int force) {
	struct messagewall_dnsdcc_profile_t *iter;
	int i;

	iter = clients[client].profile->dnsdcc;
	while (iter != NULL) {
		for (i = 0; i <= clients[client].num_parts; i++) {
			if (clients[client].dnsdcc_fd[i][iter->global->i] == -2) {
				if (force == 1) {
					if (smtp_reject(client,"DNSDCC","%e: checksum is listed",SMTP_DNSDCC,iter->score,0,&iter->global->dnsdcc,NULL) == 1)
						return 1;
				} else
					return 1;
			}
			if (clients[client].dnsdcc_fd[i][iter->global->i] >= 0) {
				if (force == 1)
					continue;
				else
					return -1;
			}
		}
		iter = iter->next;
	}

	return 0;
}