I am using the following function to encrypt my data via the OpenSSL Library in Qt:
QByteArray Crypto::Encrypt(QByteArray source, QString password)
{
EVP_CIPHER_CTX en;
unsigned char *key_data;
int key_data_len;
QByteArray ba = password.toLatin1();
key_data = (unsigned char*)ba.data();
key_data_len = strlen((char*)key_data);
int nrounds = 28;
unsigned char key[32], iv[32];
EVP_BytesToKey(EVP_aes_256_cbc(), EVP_sha1(), NULL, key_data, key_data_len, nrounds, key, iv);
QByteArray bkey = reinterpret_cast<const char*>(key) //EDIT: Contains the key afterwards
QByteArray biv = reinterpret_cast<const char*>(iv) //EDIT: Is Null afterwards
EVP_CIPHER_CTX_init(&en);
EVP_EncryptInit_ex(&en, EVP_aes_256_cbc(), NULL, key, iv);
char *input = source.data();
char *out;
int len = source.size();
int c_len = len + 16, f_len = 0;
unsigned char *ciphertext = (unsigned char *)malloc(c_len);
EVP_EncryptInit_ex(&en, NULL, NULL, NULL, NULL);
EVP_EncryptUpdate(&en, ciphertext, &c_len, (unsigned char *)input, len);
EVP_EncryptFinal_ex(&en, ciphertext+c_len, &f_len);
len = c_len + f_len;
out = (char*)ciphertext;
EVP_CIPHER_CTX_cleanup(&en);
return QByteArray(out, len);
}
"source" is in that case "12345678901234567890123456789012abc".
"password" is "1hA!dh==sJAh48S8Ak!?skiitFi120xX".
So....if I got that right, then EVP_BytesToKey() should generate a key out of the password and supplied data to decrypt the string with later.
To Base64-Encoded that key would be: "aQkrZD/zwMFU0VAqjYSWsrkfJfS28pQJXym20UEYNnE="
I don't use a salt, so no IV (should be null).
So QByteArray bkey in Base64 leaves me with "aQkrZD/zwMFU0VAqjYSWsrkfJfS28pQJXym20UEYNnE="
QByteArray bvi is giving me Null
The encryptet text is "CiUqILbZo+WJBr19IiovRVc1dqGvrastwo0k67TTrs51HB8AbJe8S4uxvB2D7Dkr".
Now I am using the following PHP function to decrypt the ciphertext with the generated key again:
<?php
function decrypt_data($data, $iv, $key) {
$cypher = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, '');
//if(is_null($iv)) {
// $ivlen = mcrypt_enc_get_iv_size($cypher);
// $iv = substr($data, 0, $ivlen);
// $data = substr($data, $ivlen);
//}
// initialize encryption handle
if (mcrypt_generic_init($cypher, $key, $iv) != -1) {
// decrypt
$decrypted = mdecrypt_generic($cypher, $data);
// clean up
mcrypt_generic_deinit($cypher);
mcrypt_module_close($cypher);
return $decrypted;
}
return false;
}
$ctext = "CiUqILbZo+WJBr19IiovRVc1dqGvrastwo0k67TTrs51HB8AbJe8S4uxvB2D7Dkr";
$key = "aQkrZD/zwMFU0VAqjYSWsrkfJfS28pQJXym20UEYNnE=";
$res = decrypt_data(base64_decode($ctext), null, base64_decode($key));
echo $res;
?>
Now I'd expect a response like "12345678901234567890123456789012abc".
What I get is "7890123456789012abc".
My string seems to be decrypted in the right way, but it's cut in half and only the last 19 characters are displayed.
Can someone please help me with that?
I'm new to encryption and can't really figure out where exactly I went wrong.
This is probably because of a misinterpretation from your part. You say:
I don't use a salt, so no IV (should be null).
But there is no reason at all why that would be the case. The EVP_BytesToKey method provided both a key and an IV. The key is obviously correct, but the IV is not. This will result in random characters in your plain text (the IV only changes the first block). As this block will likely contain control characters and what more, it may not display well.
Remember that a salt and IV may have a few things in common (should not be repeated, can be public etc.) but that they are entirely different concepts in cryptography.
Please try again with your Qt code, and this time print out the IV as well as the key...
I solved the problem with the empty initialisation vector by trial and error now, though I have no clue why the following was a problem at all.
Maybe someone can explain that to me.
Changing the line: int nrounds = 28; did the trick.
If i put any other number than 28 in there, an IV is generated and when I use it afterwards in mcrypt the ciphertext is decrypted in the correct way.
Why was it a problem to generate the key with 28 rounds with the openssl-function EVP_BytesToKey()?
I reduced it to 5 rounds now, but I'm curious whether this problem might happen again with a password-rounds-combination that has the possibility to generate such a Null-IV.
I don't realy know how the process of the IV generation is handled in this function.
Related
I have an application running on php which have some values encrypted using openssl encrption by using the code below
<?php
define('OSSLENCKEY','14E2E2D1582A36172AE401CB826003C1');
define('OSSLIVKEY', '747E314D23DBC624E971EE59A0BA6D28');
function encryptString($data) {
$encrypt_method = "AES-256-CBC";
$key = hash('sha256', OSSLENCKEY);
$iv = substr(hash('sha256', OSSLIVKEY), 0, 16);
$output = openssl_encrypt($data, $encrypt_method, $key, 0, $iv);
$output = base64_encode($output);
return $output;
}
function decryptString($data){
$encrypt_method = "AES-256-CBC";
$key = hash('sha256', OSSLENCKEY);
$iv = substr(hash('sha256', OSSLIVKEY), 0, 16);
$output = openssl_decrypt(base64_decode($data), $encrypt_method, $key, 0, $iv);
return $output;
}
echo encryptString("Hello World");
echo "<br>";
echo decryptString("MTZHaEoxb0JYV0dzNnptbEI2UXlPUT09");
?>
I have another endpoint which runs on nodejs where I need to decrypt and encrypt values based on the above php encrypt/decrypt rule.
I have searched but could'nt find a solution for this.
I tried with the library crypto But ends up with errors Reference
My nodejs code which I have tried is given below
message = 'MTZHaEoxb0JYV0dzNnptbEI2UXlPUT09';
const cypher = Buffer.from(message, "base64");
const key = crypto.createHash('sha256').update('14E2E2D1582A36172AE401CB826003C1');//.digest('hex');
// $iv = substr(hash('sha256', '747E314D23DBC624E971EE59A0BA6D28'), 0, 16); from php returns '0ed9c2aa27a31693' need nodejs equivalent
const iv = '0ed9c2aa27a31693';
const decipher = crypto.createDecipheriv("aes-256-cbc", key, iv);
console.log( decipher.update(contents) + decipher.final());
Someone please help me to find a nodejs code for openssl encryption and decyption
Thanks in advance
There are the following problems in the code:
The key is returned hex encoded in the PHP code, so in the NodeJS code for AES-256 only the first 32 bytes must be considered for the key (PHP does this automatically).
The PHP code Base64 encodes the ciphertext implicitly, so because of the explicit Base64 encoding the ciphertext is Base64 encoded twice (which is unnecessary). Therefore, a double Base64 encoding is necessary in the NodeJS code as well.
Also, note that using a static IV is insecure (but you are probably only doing this for testing purposes).
The following NodeJS code produces the same ciphertext as the PHP code:
const crypto = require('crypto');
const plain = 'Hello World';
const hashKey = crypto.createHash('sha256');
hashKey.update('14E2E2D1582A36172AE401CB826003C1');
const key = hashKey.digest('hex').substring(0, 32);
const hashIv = crypto.createHash('sha256');
hashIv.update('747E314D23DBC624E971EE59A0BA6D28');
const iv = hashIv.digest('hex').substring(0, 16);
const cipher = crypto.createCipheriv('aes-256-cbc', key, iv);
var encrypted = cipher.update(plain, 'utf-8', 'base64');
encrypted += cipher.final('base64');
encrypted = Buffer.from(encrypted, 'utf-8').toString('base64');
console.log(encrypted); // MTZHaEoxb0JYV0dzNnptbEI2UXlPUT09
encrypted = Buffer.from(encrypted, 'base64').toString('utf-8');
const decipher = crypto.createDecipheriv('aes-256-cbc', key, iv);
var decrypted = decipher.update(encrypted, 'base64', 'utf-8');
decrypted += decipher.final('utf-8');
console.log(decrypted); // Hello World
EDIT:
As mentioned in the comments, PHP's hash() method returns the hash as a hexadecimal string by default (unless the third parameter is explicitly set to true, which is not the case in the reference code). This doubles the length, because in this encoding each byte of the hash is represented by two hex digits (hexits), i.e. 2 bytes.
Therefore it is necessary to shorten the key in the NodeJS code (see the first point of my original answer). This shortening is not necessary in the PHP code, since PHP does this implicitly (which is actually a design flaw, since this way the user does not notice a possible issue with the key).
The use of the hex string has two disadvantages:
With a hex encoded string, each byte consists of 16 possible values (0-15), as opposed to 256 possible values of a byte (0-255). This reduces the security from 256 bit to 128 bit (which is arithmetically equivalent to AES-128), see here.
Depending on the platform, the hexits a-f can be represented as lowercase or uppercase letters, which can result in different keys and IVs (without explicit agreement on one of the two cases).
For these reasons it is more secure and robust to use the raw binary data of the hash instead of the hex encoded strings. If you want to do this, then the following changes are necessary.
In the PHP code:
$key = hash('sha256', OSSLENCKEY, true);
$iv = substr(hash('sha256', OSSLIVKEY, true), 0, 16);
in the NodeJS code:
const key = hashKey.digest();
const iv = hashIv.digest().slice(0, 16)
Note, however, that this version is not compatible with the old one, i.e. encryptions before this change cannot be decrypted after the change. So the old data would have to be migrated.
How do I encrypt a file contents in PHP using OpenSSL and decrypt it in C++?
Here's my code:
$dll = file('file.dll')[0];
$iv = substr(hash('sha256', 'test'), 0, 16);
$key = substr(hash('sha256', 'test'), 0, 32);
$dll_en = openssl_encrypt($dll, "AES-256-CBC", $key, 0, $iv);
and here's c++
int main() {
/* A 256 bit key */
byte* key = (byte*)"9f86d081884c7d659a2feaa0c55ad015";
/* A 128 bit IV */
byte* iv = (byte*)"9f86d081884c7d65";
std::vector<byte> data = base64_decode("CyeJtJecBChtVSxeTLw9mYKapHwLNJed/5VVuyGOHNSTksBzH1Ym2JwLJv/LvlT9tqMEahwcX7Yj9jYVRCSnTliz/zQYk0pIi8CKTEGkqffqZd8CdA6joLMl9Ym6d+5wERgHEotURq8Kn+H3/GbUuEBUtLL9Cd1+VsKWDyqkE1c=");
byte* ciphertext = new byte[data.size()];
for (size_t i = 0; i < data.size(); i++)
{
ciphertext[i] = data.at(i);
}
byte decryptedtext[8096];
int decryptedtext_len;
decryptedtext_len = decrypt(ciphertext, data.size(), key, iv, decryptedtext);
decryptedtext[decryptedtext_len] = 0;
std::cout << decryptedtext;
return 0;
}
The decrypt function is from here
The first line of the dll is
MZ����#�� �!�L�!This program cannot be run in DOS mode.
but all I get in console is MZÉ.
What am I doing wrong?
Nothing is wrong except your choice of output method!
Since you're passing a byte* to std::cout, the only way it knows when to stop is to treat the input as a C-string, a sequence of 8-bit bytes. When it encounters one with value ZERO, it thinks it's a null terminator and stops. It's working as it should.
But your input is not ASCII! It is arbitrary, "binary" data.
You should instead use something like std::cout.write(decryptedtext, decryptedtext_len), which just chucks all your bytes out to the output stream. It's then up to your console/teletype/printer to render that as it deems fit (which may still not be identical to what you're looking for, depending on settings).
Nothing, you just get things in ASCII instead of UTF-8 while printing a binary file, and characters are skipped until a 00 valued byte is encountered rather than printed out with as a diamond with a question mark. Perform a binary compare instead.
Of course you should note that key and IV calculation of the key and even more the IV is entirely insecure in PHP mode and that CBC mode doesn't provide authentication, so the code is not as secure as it should be.
Here, I have c++ program which encodes the string and I have to decrypt in php. I have verified that the key and the iv are same in both programs, still getting false in openssl_decrypt() command.
int main(int argc, char** args)
{
unsigned char *salt = (unsigned char*)"12345678";
unsigned char *data = (unsigned char*)"123456789123450";
unsigned int count = 5;
int dlen = strlen((char*)data);
unsigned int ksize = 16;
unsigned int vsize = 12;
unsigned char *key = new unsigned char[ksize];
unsigned char *iv = new unsigned char[vsize];
int ret = EVP_BytesToKey( EVP_aes_128_gcm() , EVP_sha1(), salt, data, dlen, count, key, iv);
const EVP_CIPHER* m_cipher = EVP_aes_128_gcm();
EVP_CIPHER_CTX* m_encode;
EVP_CIPHER_CTX* m_decode;
if (!(m_encode = EVP_CIPHER_CTX_new()))
cout << "ERROR :: In encode Initiallization"<< endl;
EVP_EncryptInit_ex(m_encode, m_cipher, NULL, key, iv);
if (!(m_decode = EVP_CIPHER_CTX_new()))
cout << "ERROR :: In decode Initiallization"<< endl;
EVP_DecryptInit_ex(m_decode, m_cipher, NULL, key, iv);
unsigned char* plain = (unsigned char*)"My Name IS DON !!!";
int len = strlen((char*)plain);
unsigned char* encData = new unsigned char[len];
int c_len = len;
int f_len = 0;
EVP_EncryptInit_ex(m_encode, NULL, NULL, NULL, NULL);
EVP_EncryptUpdate(m_encode, encData, &c_len, plain, len);
EVP_EncryptFinal_ex(m_encode, encData + c_len, &f_len);
len = c_len + f_len;
cout << string( encData, encData + len)<< endl;
}
And the following is decryption code in php. "./abc_enc.txt" contains encryption string of c++ code. As I mentioned above I am getting same key and iv for both programs but openssl_decrypt function returns false. Can someone figure out what is the mistake?
<?
function EVP_BytesToKey($salt, $password) {
$ivlen = 12;
$keylen = 16;
$iterations = 5;
$hash = "";
$hdata = "";
while(strlen($hash)<$ivlen+$keylen)
{
$hdata .= $password.$salt;
$md_buf = openssl_digest($hdata, 'sha1');
for ($i = 1; $i < $iterations; $i++) {
$md_buf = openssl_digest ( hex2bin($md_buf),'sha1');
}
$hdata = hex2bin($md_buf);
$hash.= $hdata;
}
return $hash;
}
function decrypt($ivHashCiphertext, $password) {
$method = "aes-128-gcm";
$salt = "12345678";
$iterations = 5;
$ivlen = openssl_cipher_iv_length($method);
$ciphertext = $ivHashCiphertext;
$genKeyData = EVP_BytesToKey($salt, $password);
$keylen = 16;
$key = substr($genKeyData,0,$keylen);
$iv = substr($genKeyData,$keylen,$ivlen);
//var_dump($key);
//var_dump($iv);
$ret = openssl_decrypt($ciphertext, $method, $key, OPENSSL_RAW_DATA, $iv);
var_dump($ret);
return $ret;
}
$file = './abc_enc.txt';
$fileData = (file_get_contents($file));
$encrypted = $fileData;
$decrypted = decrypt($encrypted, '123456789123450');
?>
The GCM-mode provides both, confidentiality and authenticity. To verify authenticity the GCM-mode uses an authentication tag and defines a length between incl. 12 and 16 Byte for the tag. The authentication strength depends on the length of the tag, i.e. the longer the tag, the more secure the proof of authenticity.
However, in the current C++-code the authentication tag is not determined! This means that one of the main functionalities of the GCM-mode, authentication, is not used.
While the decryption in C++ using EVP is independent from the authentication (this means that the decryption is also performed even if the authentication tags differ), the decryption in PHP using openssl_decrypt is only done if the authentication is successful, i.e. in PHP the authentication tag is mandatory for decryption. Therefore, the authentication tag must be determined in the C++-code. For this purpose, the following code must be added after the EVP_EncryptFinal_ex-call:
unsigned int tsize = 16;
unsigned char *tag = new unsigned char[tsize];
EVP_CIPHER_CTX_ctrl(m_encode, EVP_CTRL_GCM_GET_TAG, tsize, tag);
Here a tagsize of 16 Byte is used. In addition, the authentication tag must be used in the PHP-code for decryption. This is done by passing the authentication tag as the 6th parameter of the openssl_decrypt-method:
$ret = openssl_decrypt($ciphertext, $method, $key, OPENSSL_RAW_DATA, $iv, $tag);
Decryption can only be performed if the tag used for decryption matches the tag used for encryption.
For the data in the posted example the C++-code generates the following authentication tag (as hexadecimal string):
f7c18e8b99587f3063383d68230c0e35
Finally, a more detailed explanation for AES-GCM with OpenSSL can be found here for encryption and decryption (including the consideration of the authentication tag).
In short
I'm neither an openSSL nor a PHP specialist. But at first sight, it appears that you might experience problems because you read and write binary data using files in text mode.
More infos about the potential problem
The encrypted data resulting from your C++ code is binary data. Your code does not show how you write the file. But unless you explicitly request the file to be in binary mode, you will get a file in text mode.
This might cause multiple issues when writing the data, since text mode allows for OS-dependent transformations to happen. Typical examples are characters with value 0x0A (new lines), skipping trailing 0x20 (space character), adding a 0x0A at the end of the file if there isn't and similar undesired transformation.
Your PHP code might open the file in an incompatible default mode, which might add further transformation if it's text mode, or avoid reverting transformations if it's binary.
This means that in the end, the string you try to decode might not be the original encrypted string !
How to solve it ?
First inspect with a binary editor the content of the file to see if it matches the expectations. Or check the expected length of the encrypted source data, the length of the file, and the length of the loaded content. If they all match, my answer is not relevant.
If it is relevant, or if you intend sooner or later to allow cross platform exchanges (e.g. windows client communicating with a linux server), then you could:
either add the necessary statements to use binary mode on both sides.
or add a Base64 encoding to transform binary into a robust ascii string on the writing side, and retransforming Base64 into binary on the reading side (openssl provides for base64 encoding and PHP has everything needed as well)
Again I have a problem with mcrypt. I am wondering why am I getting diffrent results in php and c bei encryping with rinjdael-128 cfb mode. Here is my php function:
function mcencrypt($Clear, $Pass){
$td = mcrypt_module_open('rijndael-128', '', 'cfb', '');
$iv = 'AAAAAAAAAAAAAAAA';
mcrypt_generic_init($td, $Pass, $iv);
$encrypted = mcrypt_generic($td, $Clear);
mcrypt_generic_deinit($td);
return $encrypted;
}
and my c function:
unsigned char *Encrypt( unsigned char *key, unsigned char *message, int buff_len){
unsigned char *Res;
MCRYPT mfd;
char* IV = "AAAAAAAAAAAAAAAA";
int i, blocks, key_size=16, block_size;
mfd = mcrypt_module_open("rijndael-128", NULL, "cfb", NULL);
block_size = mcrypt_enc_get_block_size(mfd);
blocks = ceil((double)buff_len/block_size);
mcrypt_generic_init(mfd, key, key_size, IV);
Res = calloc(1, (blocks *block_size)+1);
strncpy(Res, message, buff_len);
mcrypt_generic(mfd,Res,(blocks *block_size));
mcrypt_generic_deinit(mfd);
mcrypt_module_close(mfd);
return (Res);
}
when I use them in a for loop the first 26 encryptions are korect, but at the 27 the last tree signs are diffrent. This is realy very odd.
in php I make the for loop like this:
$seed ="m78otPfBLT48msvd";
$key = "r2oE61IQo7VwFXnF";
$start_y= mcencrypt($seed,$key);
$new =$start_y;
$enc_prob = mcencrypt($start_y,$key);
for ($j=1; $j<30;$j++){
$new.=$enc_prob;
echo "j: ".$j.'<br>';
echo "the new: ".$enc_prob."lenght: ".strlen($enc_prob).'<br>';
echo "new in hex for j=".$j.": ".strToHex($enc_prob).'<br>';
$enc_prob=mcencrypt($enc_prob,$key);
}
and in c like this:
int j, buff_len;
char seed[] = "m78otPfBLT48msvd", key1[]="r2oE61IQo7VwFXnF";
buff_len = strlen(seed);
unsigned char *encrypted, *encrypted2;
encrypted = Encrypt(key1, seed, buff_len);
encrypted2 = Encrypt(key1, encrypted, buff_len);
for (j=1; j<cols; j++) {
printf("j: %d\n", j);
printf("encrypted2 %s\n", string_to_hex(encrypted2, buff_len));
memcpy(encrypted2, Encrypt(key1, encrypted2, buff_len),buff_len);
}
free(encrypted);
free(encrypted2);
what is going wrong. The message and the key are the same. I'm using the same library, the same iv. I don't get it. It is strange. Please help me out on this one. Many thanks in advance!!
I figured out what the problem was. The strings in c are null terminated and by using strncpy in my encryption function was making the problems, so I just changed that in memcpy and now everything goes well. Thanks again to everybody who tried to help and took time to take a look at my problem.
For a project I'm working on, I need to encrypt and decrypt a string using Blowfish in a compatible way across NSIS and PHP.
At the moment I'm using the Blowfish++ plugin for NSIS and the mcrypt library with PHP. The problem is, I can't get them both to produce the same output.
Let's start with the NSIS Blowfish++ plugin. Basically the API is:
; Second argument needs to be base64 encoded
; base64_encode("12345678") == "MTIzNDU2Nzg="
blowfish::encrypt "test#test.com***" "MTIzNDU2Nzg="
Pop $0 ; 0 on success, 1 on failure
Pop $1 ; encrypted message on success, error message on failure
There's no mention of whether it's CBC, ECB, CFB, etc. and I'm not familiar enough with Blowfish to be able to tell by reading the mostly undocumented source. I assume it's ECB since the PHP docs for mcrypt tells me that ECB doesn't need an IV.
I've also learned by reading the source code that the Blowfish++ plugin will Base64 decode the second argument to encrypt (I'm not sure why). It also returns a Base64 encoded string.
For the PHP side of things, I'm basically using this code to encrypt:
$plainText = "test#test.com***";
$cipher = mcrypt_module_open(MCRYPT_BLOWFISH, '', MCRYPT_MODE_ECB, '');
$iv = '00000000'; // Show not be used anyway.
$key = "12345678";
$cipherText = "";
if (mcrypt_generic_init($cipher, $key, $iv) != -1)
{
$cipherText = mcrypt_generic($cipher, $plainText);
mcrypt_generic_deinit($cipher);
}
echo base64_encode($cipherText);
However, if I do all these things, I get the following output from each:
NSIS: GyCyBcUE0s5gqVDshVUB8w==
PHP: BQdlPd19zEkX5KT9tnF8Ng==
What am I doing wrong? Is the NSIS plugin not using ECB? If not, what is it using for it's IV?
OK, I've gone through that code and reproduced your results. The problem isn't the cipher mode - NSIS is using ECB. The problem is that the NSIS Blowfish code is simply broken on little-endian machines.
The Blowfish algorithm operates on two 32-bit unsigned integers. To convert between a 64 bit plaintext or ciphertext block and these two integers, the block is supposed to be interpreted as two Big Endian integers. The NSIS Blowfish plugin is instead interpreting them in host byte order - so it fails to do the right thing on little-endian hosts (like x86). This means it'll interoperate with itself, but not with genuine Blowfish implementations (like mcrypt).
I've patched Blowfish++ for you to make it do the right thing - the modified Blowfish::Encrypt and Blowfish::Decrypt are below, and the new version of blowfish.cpp is here on Pastebin.
void Blowfish::Encrypt(void *Ptr,unsigned int N_Bytes)
{
unsigned int i;
unsigned char *Work;
if (N_Bytes%8)
{
return;
}
Work = (unsigned char *)Ptr;
for (i=0;i<N_Bytes;i+=8)
{
Word word0, word1;
word0.byte.zero = Work[i];
word0.byte.one = Work[i+1];
word0.byte.two = Work[i+2];
word0.byte.three = Work[i+3];
word1.byte.zero = Work[i+4];
word1.byte.one = Work[i+5];
word1.byte.two = Work[i+6];
word1.byte.three = Work[i+7];
BF_En(&word0, &word1);
Work[i] = word0.byte.zero;
Work[i+1] = word0.byte.one;
Work[i+2] = word0.byte.two;
Work[i+3] = word0.byte.three;
Work[i+4] = word1.byte.zero;
Work[i+5] = word1.byte.one;
Work[i+6] = word1.byte.two;
Work[i+7] = word1.byte.three;
}
Work = NULL;
}
void Blowfish::Decrypt(void *Ptr, unsigned int N_Bytes)
{
unsigned int i;
unsigned char *Work;
if (N_Bytes%8)
{
return;
}
Work = (unsigned char *)Ptr;
for (i=0;i<N_Bytes;i+=8)
{
Word word0, word1;
word0.byte.zero = Work[i];
word0.byte.one = Work[i+1];
word0.byte.two = Work[i+2];
word0.byte.three = Work[i+3];
word1.byte.zero = Work[i+4];
word1.byte.one = Work[i+5];
word1.byte.two = Work[i+6];
word1.byte.three = Work[i+7];
BF_De(&word0, &word1);
Work[i] = word0.byte.zero;
Work[i+1] = word0.byte.one;
Work[i+2] = word0.byte.two;
Work[i+3] = word0.byte.three;
Work[i+4] = word1.byte.zero;
Work[i+5] = word1.byte.one;
Work[i+6] = word1.byte.two;
Work[i+7] = word1.byte.three;
}
Work = NULL;
}