source: box/trunk/lib/backupclient/BackupClientCryptoKeys.h @ 2249

// --------------------------------------------------------------------------
//
// File
//              Name:    BackupClientCryptoKeys.h
//              Purpose: Format of crypto keys file, and function for setting everything up
//              Created: 1/12/03
//
// --------------------------------------------------------------------------

#ifndef BACKUPCLIENTCRYTOKEYS__H
#define BACKUPCLIENTCRYTOKEYS__H


// All keys are the maximum size that Blowfish supports. Since only the
// setup time is affected by key length (encryption same speed whatever)
// there is no disadvantage to using long keys as they are never
// transmitted and are static over long periods of time.


// All sizes in bytes. Some gaps deliberately left in the used material.

// How long the key material file is expected to be
#define BACKUPCRYPTOKEYS_FILE_SIZE                                              1024

// key for encrypting filenames (448 bits)
#define BACKUPCRYPTOKEYS_FILENAME_KEY_START                             0
#define BACKUPCRYPTOKEYS_FILENAME_KEY_LENGTH                    56
#define BACKUPCRYPTOKEYS_FILENAME_IV_START                              (0 + BACKUPCRYPTOKEYS_FILENAME_KEY_LENGTH)
#define BACKUPCRYPTOKEYS_FILENAME_IV_LENGTH                             8

// key for encrypting attributes (448 bits)
#define BACKUPCRYPTOKEYS_ATTRIBUTES_KEY_START                   (BACKUPCRYPTOKEYS_FILENAME_KEY_START+64)
#define BACKUPCRYPTOKEYS_ATTRIBUTES_KEY_LENGTH                  56

// Blowfish key for encrypting file data (448 bits (max blowfish key length))
#define BACKUPCRYPTOKEYS_FILE_KEY_START                                 (BACKUPCRYPTOKEYS_ATTRIBUTES_KEY_START+64)
#define BACKUPCRYPTOKEYS_FILE_KEY_LENGTH                                56

// key for encrypting file block index entries
#define BACKUPCRYPTOKEYS_FILE_BLOCK_ENTRY_KEY_START             (BACKUPCRYPTOKEYS_FILE_KEY_START+64)
#define BACKUPCRYPTOKEYS_FILE_BLOCK_ENTRY_KEY_LENGTH    56

// Secret for hashing attributes
#define BACKUPCRYPTOKEYS_ATTRIBUTE_HASH_SECRET_START    (BACKUPCRYPTOKEYS_FILE_BLOCK_ENTRY_KEY_START+64)
#define BACKUPCRYPTOKEYS_ATTRIBUTE_HASH_SECRET_LENGTH   128

// AES key for encrypting file data (256 bits (max AES key length))
#define BACKUPCRYPTOKEYS_FILE_AES_KEY_START                             (BACKUPCRYPTOKEYS_ATTRIBUTE_HASH_SECRET_START+128)
#define BACKUPCRYPTOKEYS_FILE_AES_KEY_LENGTH                    32


void BackupClientCryptoKeys_Setup(const std::string& rKeyMaterialFilename);

#endif // BACKUPCLIENTCRYTOKEYS__H