File indexing completed on 2025-01-05 04:37:19

 /*
     SPDX-FileCopyrightText: 2005 Joris Guisson <joris.guisson@gmail.com>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 #ifndef MSERC4ENCRYPTOR_H
 #define MSERC4ENCRYPTOR_H
 
 #include <gcrypt.h>
 #include <ktorrent_export.h>
 #include <util/constants.h>
 #include <util/sha1hash.h>
 
 using bt::Uint32;
 using bt::Uint8;
 
 namespace mse
 {
 /**
  * @author Joris Guisson <joris.guisson@gmail.com>
  *
  * RC4 encryptor. Uses the RC4 algorithm to encrypt and decrypt data.
  * This class has a static encryption buffer, which makes it not thread safe
  * because the buffer is not protected by mutexes.
  */
 class KTORRENT_EXPORT RC4Encryptor
 {
 public:
     RC4Encryptor(const bt::SHA1Hash &dkey, const bt::SHA1Hash &ekey);
     virtual ~RC4Encryptor();
 
     /**
      * Decrypt some data, decryption happens in place (original data gets overwritten)
      * @param data The data
      * @param len Size of the data
      */
     void decrypt(Uint8 *data, Uint32 len);
 
     /**
      * Encrypt the data. Encryption happens into the static buffer.
      * So that the data passed to this function is never overwritten.
      * If we send pieces we point directly to the mmap region of data,
      * this cannot be overwritten, hence the static buffer.
      * @param data The data
      * @param len The length of the data
      * @return Pointer to the static buffer
      */
     const Uint8 *encrypt(const Uint8 *data, Uint32 len);
 
     /**
      * Encrypt data, encryption will happen in the same buffer. So data will
      * be changed replaced by it's encrypted version.
      * @param data The data to encrypt
      * @param len The length of the data
      */
     void encryptReplace(Uint8 *data, Uint32 len);
 
 private:
     gcry_cipher_hd_t enc;
     gcry_cipher_hd_t dec;
 };
 
 }
 
 #endif