win32/ext/lua-wdk/COPYRIGHT


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34

Lua License
-----------

Lua is licensed under the terms of the MIT license reproduced below.
This means that Lua is free software and can be used for both academic
and commercial purposes at absolutely no cost.

For details and rationale, see http://www.lua.org/license.html .

===============================================================================

Copyright (C) 1994-2011 Lua.org, PUC-Rio.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

===============================================================================

(end of COPYRIGHT)
/* XChat-WDK
 * Copyright (c) 2010-2012 Berke Viktor.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdio.h>
#include <string.h>
#include <malloc.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <openssl/sha.h>

#include "xchat-plugin.h"

#define BUFSIZE 32768
#define DEFAULT_LIMIT 256									/* default size is 256 MiB */

#ifndef snprintf
#define snprintf _snprintf
#endif
#ifndef stat64
#define stat64 _stat64
#endif

static xchat_plugin *ph;									/* plugin handle */
static const char name[] = "Checksum";
static const char desc[] = "Calculate checksum for DCC file transfers";
static const char version[] = "3.0";

/* Use of OpenSSL SHA256 interface: http://adamlamers.com/?p=5 */
static void
sha256_hash_string (unsigned char hash[SHA256_DIGEST_LENGTH], char outputBuffer[65])
{
	int i;
	for (i = 0; i < SHA256_DIGEST_LENGTH; i++)
	{
		sprintf (outputBuffer + (i * 2), "%02x", hash[i]);
	}
	outputBuffer[64] = 0;
}

static void
sha256 (char *string, char outputBuffer[65])
{
	int i;
	unsigned char hash[SHA256_DIGEST_LENGTH];
	SHA256_CTX sha256;

	SHA256_Init (&sha256);
	SHA256_Update (&sha256, string, strlen (string));
	SHA256_Final (hash, &sha256);

	for (i = 0; i < SHA256_DIGEST_LENGTH; i++)
	{
		sprintf (outputBuffer + (i * 2), "%02x", hash[i]);
	}
	outputBuffer[64] = 0;
}

static int
sha256_file (char *path, char outputBuffer[65])
{
	int bytesRead;
	unsigned char *buffer;
	unsigned char hash[SHA256_DIGEST_LENGTH];
	SHA256_CTX sha256;

	FILE *file = fopen (path, "rb");
	if (!file)
	{
		return -534;
	}

	SHA256_Init (&sha256);
	buffer = malloc (BUFSIZE);
	bytesRead = 0;

	if (!buffer)
	{
		return ENOMEM;
	}

	while ((bytesRead = fread (buffer, 1, BUFSIZE, file)))
	{
		SHA256_Update (&sha256, buffer, bytesRead);
	}

	SHA256_Final (hash, &sha256);
	sha256_hash_string (hash, outputBuffer);

	fclose (file);
	free (buffer);
	return 0;
}

static void
set_limit (char* size)
{
	int buffer = atoi (size);

	if (buffer > 0 && buffer < INT_MAX)
	{
		if (xchat_pluginpref_set_int (ph, "limit", buffer))
		{
			xchat_printf (ph, "File size limit has successfully been set to: %d MiB\n", buffer);
		}
		else
		{
			xchat_printf (ph, "File access error while saving!\n");
		}
	}
	else
	{
		xchat_printf (ph, "Invalid input!\n");
	}
}

static int
get_limit ()
{
	int size = xchat_pluginpref_get_int (ph, "limit");

	if (size <= -1 || size >= INT_MAX)
	{
		return DEFAULT_LIMIT;
	}
	else
	{
		return size;
	}
}

static void
print_limit ()
{
	xchat_printf (ph, "File size limit for checksums: %d MiB", get_limit ());
}

static int
dccrecv_cb (char *word[], void *userdata)
{
	int result;
	struct stat64 buffer;									/* buffer for storing file info */
	char sum[65];											/* buffer for checksum */

	result = stat64 (word[2], &buffer);
	if (result == 0)										/* stat returns 0 on success */
	{
		if (buffer.st_size <= (unsigned long long) get_limit () * 1048576)
		{
			sha256_file (word[2], sum);						/* word[2] is the full filename */
			/* try to print the checksum in the privmsg tab of the sender */
			xchat_set_context (ph, xchat_find_context (ph, NULL, word[3]));
			xchat_printf (ph, "SHA-256 checksum for %s (local):  %s\n", word[1], sum);
		}
		else
		{
			xchat_set_context (ph, xchat_find_context (ph, NULL, word[3]));
			xchat_printf (ph, "SHA-256 checksum for %s (local):  (size limit reached, no checksum calculated, you can increase it with /CHECKSUM INC)\n", word[1]);
		}
	}
	else
	{
		xchat_printf (ph, "File access error!\n");
	}

	return XCHAT_EAT_NONE;
}

static int
dccoffer_cb (char *word[], void *userdata)
{
	int result;
	struct stat64 buffer;									/* buffer for storing file info */
	char sum[65];											/* buffer for checksum */

	result = stat64 (word[3], &buffer);
	if (result == 0)										/* stat returns 0 on success */
	{
		if (buffer.st_size <= (unsigned long long) get_limit () * 1048576)
		{
			sha256_file (word[3], sum);						/* word[3] is the full filename */
			xchat_commandf (ph, "quote PRIVMSG %s :SHA-256 checksum for %s (remote): %s", word[2], word[1], sum);
		}
		else
		{
			xchat_set_context (ph, xchat_find_context (ph, NULL, word[3]));
			xchat_printf (ph, "quote PRIVMSG %s :SHA-256 checksum for %s (remote): (size limit reached, no checksum calculated)", word[2], word[1]);
		}
	}
	else
	{
		xchat_printf (ph, "File access error!\n");
	}

	return XCHAT_EAT_NONE;
}

static void
checksum (char *word[], void *userdata)
{
	if (!stricmp ("GET", word[2]))
	{
		print_limit ();
	}
	else if (!stricmp ("SET", word[2]))
	{
		set_limit (word[3]);
	}
	else
	{
		xchat_printf (ph, "Usage: /CHECKSUM GET|INC|DEC\n");
		xchat_printf (ph, "  GET - print the maximum file size (in MiB) to be hashed\n");
		xchat_printf (ph, "  SET <filesize> - set the maximum file size (in MiB) to be hashed\n");
	}
}

int
xchat_plugin_init (xchat_plugin *plugin_handle, char **plugin_name, char **plugin_desc, char **plugin_version, char *arg)
{
	ph = plugin_handle;

	*plugin_name = name;
	*plugin_desc = desc;
	*plugin_version = version;

	/* this is required for the very first run */
	if (xchat_pluginpref_get_int (ph, "limit") == -1)
	{
		xchat_pluginpref_set_int (ph, "limit", DEFAULT_LIMIT);
	}

	xchat_hook_command (ph, "CHECKSUM", XCHAT_PRI_NORM, checksum, "Usage: /CHECKSUM GET|SET", 0);
	xchat_hook_print (ph, "DCC RECV Complete", XCHAT_PRI_NORM, dccrecv_cb, NULL);
	xchat_hook_print (ph, "DCC Offer", XCHAT_PRI_NORM, dccoffer_cb, NULL);

	xchat_printf (ph, "%s plugin loaded\n", name);
	return 1;
}

int
xchat_plugin_deinit (void)
{
	xchat_printf (ph, "%s plugin unloaded\n", name);
	return 1;
}