Encryption

Note about Replacement/Substitution and Shuffling/Reordering

Replacement/Substitution and Shuffling/Reordering are the two techniques EMA uses. They are always used simultaneously on the same block of bytes for both encryption and decryption.

Replacement and Substitution

The Replacement and Substitution processes affect the entire block of bytes and do not move bytes. For example, if we have a block of 100.000 bytes and its respective sub-key, for example, of 200.000 bytes, both the processes replace the values of the source data with the first 100.000 values of the key (source_data XOR key_value) for all 100.000 bytes. If the sub-key only had 10.000 bytes, it will replace the source data values in blocks of 10.000 bytes to reach 100.000 bytes. If the byte block had 100.015 bytes, the first 15 bytes of the key would be used in the last cycle for that block of bytes.

The following example is a piece of the header byte block of 758-byte (highlighted) before the replacement. Data you can see highlighted includes points from 2. to 18. of the section of the page “The pre-encryption data structure -> Only one byte block (first and last byte block)“.

JJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJ9b016d8e946b7f64701c8e45b1b3d1dc H  =	 

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BUILTIN\Administrators (Alias) C : \ U s e r s \ g u e s t \ e m a \ s r c \ 4 0 0 0 0 0 0 _ J . t x tNT AUTHORITY\SYSTEM:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW, BUILTIN\Administrators:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW, BUILTIN\Users:READ_DATA/READ_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/READ_ACL/SYNCHRONIZE:ALLOW, \Everyone:READ_DATA/READ_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/READ_ACL/SYNCHRONIZE:ALLOWJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJ

The following block is identical to the previous one, but after replacement. It can be seen that the number of bytes remains exactly the same, but the values have changed (758 bytes):

HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHb304201a`1ca43c/d_6adc0/`./`/c55þFþþ;þÿÿŒ6tÿŒ1¡GJÿŒ1 ;HÿŒ1¡GJþþþ Cþþþÿ@SGJRGLZ?bkglgqrp_rmpq&?jg_q'þAþ8þZþSþqþcþpþqþZþeþsþcþqþrþZþcþkþ_þZþqþpþaþZþ2þ.þ.þ.þ.þ.þ.þ]þHþ,þrþvþrLR?SRFMPGRWZQWQRCK8PC?B]B?R?-UPGRC]B?R?-?NNCLB]B?R?-PC?B]L?KCB]?RRPQ-UPGRC]L?KCB]?RRPQ-CVCASRC-BCJCRC]AFGJB-PC?B]?RRPG@SRCQ-UPGRC]?RRPG@SRCQ-BCJCRC-PC?B]?AJ-UPGRC]?AJ-UPGRC]MULCP-QWLAFPMLGXC8?JJMU*@SGJRGLZ?bkglgqrp_rmpq8PC?B]B?R?-UPGRC]B?R?-?NNCLB]B?R?-PC?B]L?KCB]?RRPQ-UPGRC]L?KCB]?RRPQ-CVCASRC-BCJCRC]AFGJB-PC?B]?RRPG@SRCQ-UPGRC]?RRPG@SRCQ-BCJCRC-PC?B]?AJ-UPGRC]?AJ-UPGRC]MULCP-QWLAFPMLGXC8?JJMU*@SGJRGLZSqcpq8PC?B]B?R?-PC?B]L?KCB]?RRPQ-CVCASRC-PC?B]?RRPG@SRCQ-PC?B]?AJ-QWLAFPMLGXC8?JJMU*ZCtcpwmlc8PC?B]B?R?-PC?B]L?KCB]?RRPQ-CVCASRC-PC?B]?RRPG@SRCQ-PC?B]?AJ-QWLAFPMLGXC8?JJMUHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH

As can be seen, the replacement range remains 758 bytes. Only values of data origin have been replaced without adding or removing anything.

Shuffling and Reordering

Shuffling and reordering processes act on the entire block of bytes, but in a different way from Replacement and Substitution to achieve the best performance of the encryption and decryption processes. If we tried to achieve complete shuffling within the entire byte block, performance would degrade frighteningly. So the shuffling is limited to a narrow range compared to the size of the byte block used. All data are swapped but the first data value is exchanged with the data value that has the first key value as its index, and so on. It is clear that origin data values with an index greater than 255 are always exchanged with origin data values that have 0 to 255 as their index.

The following example is a piece of the header byte block of 758-byte (highlighted) before the shuffling. Data you can see highlighted includes points from 2. to 18. of the section of the page “The pre-encryption data structure -> Only one byte block (first and last byte block)“.

JJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJ11033c5d1cbead55ef6202a2abfab710 H  =	  
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Ž3£IL   E     BUILTIN\Administrators (Alias) C : \ U s e r s \ g u e s t \ e m a \ s r c \ 4 0 0 0 0 0 0 _ J . t x tNT AUTHORITY\SYSTEM:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW, BUILTIN\Administrators:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW, BUILTIN\Users:READ_DATA/READ_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/READ_ACL/SYNCHRONIZE:ALLOW, \Everyone:READ_DATA/READ_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/READ_ACL/SYNCHRONIZE:ALLOWJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJ

The following is the same as above but after the shuffling (2472-byte):

JJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJdJJJJJJJJJJJJJJJJJJJJJJJJJJcJJ5fJJJJJJJJJJ	7JJJJJJJJJJJJJJJJJJ=JeJJJJJJJJ=
JJJJJJJJJJJJJ JJJJJJJ;¢JIJJJ2JJJ4 2J8JJJJJBeJJbsJŽJJaeJlJJ5JJ JæJJJJJJ JJ NtJ4  J£J\r JmJ1JJJJJcJ3 JJJJ JbJJ JJJJJJ  7s JJ7S 3 JT
AT J JJrr JJeJJJJJC JJJ1JPJ.ALgJ  J£D\JJ NHJ tJJIJ J  /\JeTJDIf JTE\JJEi JELJW
TJRJA6/JJRJDJII TNJ T0NJJSJE_AcADYRUJJ:J\JLA_aJT)D6U /JBJRE_tAIEETRAJLJJ_ JŽd _JJY_WOJER_JIWJD:eCJJLTmEAUWEMEU EEW NJ:CeJPA5\sJSJŽRRJTEACJ8/TD iJJNLTs
JJ/JJLE5OãELNATP rT_S__AA/AJAAT AsREIHDRJTRTJaTT0,mTJIJrSEJsWdA9JTAWRA A/ENTTH_T_WŽDJJJJEIE_f04R _AETEJDAHDAITIDJA/DEDJJ
 _EIDICJJJRW0JDE_/TIXAR__SNRAnLWEDJWJE\/  AAJDCD/nL_/UAMT:8UJJDLELC3CUUJE_I
THERREA/TTBB/EJTLNT_AXUSDEo_ST R0LJ,NAEAS(NEiBUZtEUR/BeTAEYREDS/AHMRETJ IEJBTRELO:O:RAEMTY/W/As:EDCRO/NERSD_REJATN/SJaEDDJ_RRrEy /URs_RLTZIAIST_RTADEJNLAIRNYTSTJAuJALIEEET/A_URo/JJnJTT_eJEEJJSsJ/JJPJ_JMt_JEJJRJ_TJLLToJEAOJE\iWJJJHJJRJJEDAJ/RJOINAAJJIAJJD/AJJJRJJNTAJRJJ OJDJAIJZCJEJJRJJJJJMJJ IJJJTJUrESJWJJJAJJTtJJJD_AJ/JsEUJJJJIJJJJCJJJAJCJMJAJJJJJJAJJ/JCTLJJL0J_RCJJJJJJJJJAAJJJIJNJJ OJJJJEEAJJJJJJJJJJJCJ/JJEJ_BJ JJJJNJJJJSEZJJ,JJJJJLTAJEJJ3JJJJJJJJJJTJEJDJDJJJJJ:JJNJJJJJJTXJJJJ/JJJJ JJeJxJJRJJJJJJJJJJJYOSJJJJJJJJJJJJJ_JrJJJJJJJJJJJJJJJAJJJJJJEJJJJJ0J/JJJJJDJJEJJJJJJJJJJTJJJJJJJJJJJCJJJBJJJJJJJJJJJJJJJJJJJJJJJJJJJDJJJJJJJJJJJJJJJEAJJJJAJJJ/JIJOJTJJJRJJJJJJJJJJJJJJJJJJJJJJJJJtJTJJJJJJJJJJJJHJ_JJ_JJs\JJJJJJJJJJJJJJJJJDJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJRJJJJ/JJJEJJJJJE/IJ/JJJJ\TJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJiJJJJJJJJJJJJJJJJJJJJJJJJJJJTJJJJJJJJJJJJJJJJJJIJJJJJJJJJJJJJXJJJJJJJJJJJJJJJJDJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJCJJJJJJJvJJRJJJWJJJJJ:JJJJJJJJJJJJJLLJJJJJJJJJJJJJJJJIJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJTJJDJJJJJJJJJJJJJJJJJJJJJJJJ/JJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJWJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJEJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJNJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJUJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJ

The shuffled data range (2472 bytes) is larger than the replacement range alone (758 bytes) because moves the origin data header outside its border. Trying to decipher it, even in plain text and without first applying value substitution, is not easy without knowing the length or contents of the key.

Note that the ‘J’ character, which is not present in the header, was intentionally inserted to aid in understanding how substitution and shuffling work. Typically, instead of ‘J’ characters, a fixed number of random bytes can be found above the header and the source data can be found below the header.
In each of the examples above, we used two keys with only two values (NUL -> 0 and SOH -> 1) to visually demonstrate the effects of substitution and shuffling.
Blanks you can see in the previous examples really are not printable bytes (chars).

The core of EMA encryption and decryption

• The following simple and short method cryptCore() performs the encryption and the decryption in EMA software

  /*
   * Copyright 2021-2024 EMA (Encryption by Masking)
   * Ema.jar (not static, instantiatable) - Version 1.24.0310.0 (2024.03.10)
   * Developer: Stefano Fazzino - Udine (Italy)
   * For info and documentation visit https://www.creoart.com
   *                                    ***
   * 1. EMA is free to use for personal non-profit purposes.
   * 2. Public and private companies, universities, colleges, schools, research
   *    institutes, hospitals, governmental and non-governmental agencies and the
   *    military are only allowed to test and try it freely. For all other purposes
   *    they have to ask for permission to use it.
   * 3. You may not copy and/or include parts of this software in your own code
   *    without the explicit permission of the developer.
   * 2. Before running the program:
   *    - check its checksum and if it does not match to the one signed, DO NOT RUN
   *    - also check the program Ema.jar (not static, instantiatable)
   *     by sites like https://www.virustotal.com
   * 5. For bugs, suggestions, vulnerabilities or anything else send an email:
   *                        i n f o @ c r e o a r t . c o m
   * 6. The developer cannot be held responsible in any way for any damages,
   *    malfunction or any other consequence related to the use of this software.
   * 7. If you do not agree, please avoid using this software.
   *                                     ***
   *                                     ***
   * @param sign is 1 or -1 and means encryption or decryption
   */
  private static void cryptCore(int sign) {

    // 'data[]'       pre-encryption data byte array to encrypt and decrypt
    // 'key[]'        byte array of key values
    // 'beginIdx'     beginning index of data[] to encrypt or decrypt
    // 'endIdx'       end index of data[] to encrypt or decrypt
    // 'dataLen'      length of the data[] byte array
    // 'keyLen'       total length of the key[] array
    // 'subKeyLen'    length of sub-keys, half of the keyLen
    // 'data_i'       single byte of data[] byte array
    // 'replacement'  index to perform the replacement/substitution
    // 'shuffling'    index to perform the shuffling/reordering

    int beginIdx = (dataLen - 1) * ((1 - sign) / 2);
    int endIdx = dataLen - beginIdx;
    int subKeyLen = keyLen / 2;

    for (int i = beginIdx; i * sign < endIdx; i += sign) {

      byte data_i = data[i];
      int replacement = i % subKeyLen, shuffling = key[subKeyLen + replacement] & 0xFF;

      data[i] = (byte) (data[shuffling] ^ key[replacement]);
      data[shuffling] = (byte) (data_i ^ key[replacement]);

    }

  }

Encrypt a file

The easiest way to encrypt a file while retaining all default settings is as follows:

• setKey(“C:\\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key”);
• fileEncryption(“C:\\Users\\guest\\ema\\src\\4000000.txt”, “C:\\”);

This requires specifying the key file, the origin file and output directory as absolute paths.

Here is the result:

2024.04.27 10:27:35.258 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 10:27:35.259 RUNNING setKeyFilename() :: 
2024.04.27 10:27:35.259   SETTING the key
2024.04.27 10:27:35.260   C:\Users\guest\ema\key\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key     4.194.304-byte
2024.04.27 10:27:35.260     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 10:27:35.260     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 10:27:35.345   
2024.04.27 10:27:35.345   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 10:27:35.346   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 10:27:35.346   
2024.04.27 10:27:35.347 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 10:27:35.347 RUNNING fileEncryption() :: 
2024.04.27 10:27:35.349   SETTING 'C:' as output encrypted files directory                                           
2024.04.27 10:27:35.352   FILE TO ENCRYPT
2024.04.27 10:27:35.352   C:\Users\guest\ema\src\4000000.txt                                                  4.000.000-byte
2024.04.27 10:27:35.353   ..................................................................................................
2024.04.27 10:27:35.353   ENCRYPTION KEY
2024.04.27 10:27:35.353   C:\Users\guest\ema\key\\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key    4.194.304-byte
2024.04.27 10:27:35.355     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 10:27:35.353     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 10:27:35.355   
2024.04.27 10:27:35.355   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 10:27:35.356   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 10:27:35.356   ..................................................................................................
2024.04.27 10:27:35.429   ENCRYPTION SETTINGS
2024.04.27 10:27:35.430    Encryption execution core: ENABLED
2024.04.27 10:27:35.430    Checksum calculation: ENABLED with MD5 algorithm
2024.04.27 10:27:35.431    Encryption details: ENABLED
2024.04.27 10:27:35.431    Use a random name to save the encrypted file: ENABLED
2024.04.27 10:27:35.432   ..................................................................................................
2024.04.27 10:27:35.432   STARTING THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.27 10:27:35.530    Reading the prepared byte block 0000000001          00088212µs                     2.097.152-byte
2024.04.27 10:27:35.652    Calculating MD5 checksum                            00007668µs
2024.04.27 10:27:35.667    Encrypting the byte block 0000000001                00013686µs
2024.04.27 10:27:35.670    Writing the encrypted byte block 0000000001         00002451µs                     2.097.152-byte
2024.04.27 10:27:35.671    ....
2024.04.27 10:27:35.672    ....
2024.04.27 10:27:35.672    ....
2024.04.27 10:27:35.673    ....
2024.04.27 10:27:35.680    Reading the prepared byte block 0000000002          00001252µs                     1.934.556-byte
2024.04.27 10:27:35.681    Calculating MD5 checksum                            00004331µs
2024.04.27 10:27:35.689    Encrypting the byte block 0000000002                00007681µs
2024.04.27 10:27:35.692    Writing the encrypted byte block 0000000002         00001559µs                     1.934.556-byte
2024.04.27 10:27:35.692   FINISHED THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.27 10:27:35.693   ..................................................................................................
2024.04.27 10:27:35.693   OVERALL TIMES
2024.04.27 10:27:35.695    Time to read 0000000002 byte blocks                 00000089ms
2024.04.27 10:27:35.696    Time to calculate the MD5 checksum                  00000011ms
2024.04.27 10:27:35.696    Time to complete the encryption                     00000021ms
2024.04.27 10:27:35.696    Time to write 0000000002 byte blocks                00000004ms
2024.04.27 10:27:35.697    Total time                                          00000126ms
2024.04.27 10:27:35.698   ..................................................................................................
2024.04.27 10:27:35.698   SAVING THE ENCRYPTED FILE
2024.04.27 10:27:35.699   C:\1714206455488377100_R2OBN4FwRY4Qp7hoIYdrema8JAKCPX8B.msk                         4.031.708-byte
2024.04.27 10:27:35.699   ..................................................................................................
2024.04.27 10:27:35.700   The checksum MD5 was calculated
2024.04.27 10:27:35.700   Encryption performed successfully
2024.04.27 10:27:35.701   
2024.04.27 10:27:35.701 FINISHED fileEncryption() ::

We obtain the same result by configuring the necessary paths:

• setKeyFilesDirectory(“C:\\”);
• setOriginFilesDirectory(“C:\\Users\\guest\\ema\\src\\”);
• setEncryptedFilesDirectory(“C:\\”);
• setKey(“1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key”);
• fileEncryption(“4000000.txt”, “”); // note that the output directory is empty

The result:

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:31:21.778 RUNNING setKeyFilesDirectory() :: 
2024.04.27 08:31:21.782   SETTING 'C:\' as input/output keys files directory                                         
2024.04.27 08:31:21.782   
2024.04.27 08:31:21.782 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:31:21.783 RUNNING setOriginFilesDirectory() :: 
2024.04.27 08:31:21.783   SETTING 'C:\Users\guest\ema\src\' as origin files directory                                
2024.04.27 08:31:21.783   
2024.04.27 08:31:21.783 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:31:21.784 RUNNING setEncryptedFilesDirectory() :: 
2024.04.27 08:31:21.784   SETTING 'C:\' as output encrypted files directory                                          
2024.04.27 08:31:21.784   
2024.04.27 08:31:21.784 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:31:21.784 RUNNING setKeyFilename() :: 
2024.04.27 08:31:21.785   SETTING the key
2024.04.27 08:31:21.785   C:\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key                         4.194.304-byte
2024.04.27 08:31:21.786     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 08:31:21.785     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 08:31:21.858   
2024.04.27 08:31:21.858   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 08:31:21.859   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 08:31:21.859   
2024.04.27 08:31:21.859 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:31:21.859 RUNNING fileEncryption() :: 
2024.04.27 08:31:21.859   FILE TO ENCRYPT
2024.04.27 08:31:21.859   C:\Users\guest\ema\src\4000000.txt                                                  4.000.000-byte
2024.04.27 08:31:21.859   ..................................................................................................
2024.04.27 08:31:21.860   ENCRYPTION KEY
2024.04.27 08:31:21.860   C:\\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key                        4.194.304-byte
2024.04.27 08:31:21.860     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 08:31:21.860     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 08:31:21.860   
2024.04.27 08:31:21.860   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 08:31:21.860   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 08:31:21.861   ..................................................................................................
2024.04.27 08:31:21.896   ENCRYPTION SETTINGS
2024.04.27 08:31:21.897    Encryption execution core: ENABLED
2024.04.27 08:31:21.897    Checksum calculation: ENABLED with MD5 algorithm
2024.04.27 08:31:21.897    Encryption details: ENABLED
2024.04.27 08:31:21.897    Use a random name to save the encrypted file: ENABLED
2024.04.27 08:31:21.897   ..................................................................................................
2024.04.27 08:31:21.897   STARTING THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.27 08:31:21.909    Reading the prepared byte block 0000000001          00002887µs                     2.097.152-byte
2024.04.27 08:31:21.910    Calculating MD5 checksum                            00007822µs
2024.04.27 08:31:21.926    Encrypting the byte block 0000000001                00016086µs
2024.04.27 08:31:21.928    Writing the encrypted byte block 0000000001         00001623µs                     2.097.152-byte
2024.04.27 08:31:21.929    ....
2024.04.27 08:31:21.929    ....
2024.04.27 08:31:21.929    ....
2024.04.27 08:31:21.929    ....
2024.04.27 08:31:21.936    Reading the prepared byte block 0000000002          00001234µs                     1.934.556-byte
2024.04.27 08:31:21.936    Calculating MD5 checksum                            00004204µs
2024.04.27 08:31:21.943    Encrypting the byte block 0000000002                00006816µs
2024.04.27 08:31:21.945    Writing the encrypted byte block 0000000002         00001449µs                     1.934.556-byte
2024.04.27 08:31:21.945   FINISHED THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.27 08:31:21.946   ..................................................................................................
2024.04.27 08:31:21.946   OVERALL TIMES
2024.04.27 08:31:21.946    Time to read 0000000002 byte blocks                 00000004ms
2024.04.27 08:31:21.946    Time to calculate the MD5 checksum                  00000012ms
2024.04.27 08:31:21.947    Time to complete the encryption                     00000022ms
2024.04.27 08:31:21.947    Time to write 0000000002 byte blocks                00000003ms
2024.04.27 08:31:21.947    Total time                                          00000042ms
2024.04.27 08:31:21.947   ..................................................................................................
2024.04.27 08:31:21.947   SAVING THE ENCRYPTED FILE
2024.04.27 08:31:21.947   C:\\1714206681980030100_T89wmNjdjWi7P9A4WU9n2BUxRJKeQQpo.msk                        4.031.708-byte
2024.04.27 08:31:21.948   ..................................................................................................
2024.04.27 08:31:21.948   The checksum MD5 was calculated
2024.04.27 08:31:21.948   Encryption performed successfully
2024.04.27 08:31:21.948   
2024.04.27 08:31:21.948 FINISHED fileEncryption() ::

If you do not specify a key:

• fileEncryption(“4000000.txt”, “”);

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:37:08.205 RUNNING disableEncryptionDetails() :: 
2024.04.27 08:37:08.206   DISABLING details in encryption stage
2024.04.27 08:37:08.206   
2024.04.27 08:37:08.206 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:37:08.206 RUNNING fileEncryption() :: 
2024.04.27 08:37:08.206   ERROR: Key NOT SET

If you do not specify a correct path for the origin file:

• setKeyFilesDirectory(“C:\\Users\\guest\\ema\\key\\”);
• setEncryptedFilesDirectory(“C:\\Users\\guest\\ema\\msk\\”);
• setKeyFilename(“1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key”);
• fileEncryption(“4000000.txt”, “”);

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:39:14.994 RUNNING setKeyFilesDirectory() :: 
2024.04.27 08:39:14.998   SETTING 'C:\Users\guest\ema\key\' as input/output keys files directory                     
2024.04.27 08:39:14.998   
2024.04.27 08:39:14.998 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:39:14.999 RUNNING setEncryptedFilesDirectory() :: 
2024.04.27 08:39:14.999   SETTING 'C:\Users\guest\ema\msk\' as output encrypted files directory                      
2024.04.27 08:39:14.999   
2024.04.27 08:39:14.999 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:39:15.000 RUNNING setKeyFilename() :: 
2024.04.27 08:39:15.000   SETTING the key
2024.04.27 08:39:15.000   C:\Users\guest\ema\key\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key     4.194.304-byte
2024.04.27 08:39:15.000     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 08:39:15.000     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 08:39:15.064   
2024.04.27 08:39:15.064   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 08:39:15.064   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 08:39:15.064   
2024.04.27 08:39:15.064 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:39:15.065 RUNNING fileEncryption() :: 
2024.04.27 08:39:15.065   ERROR: '4000000.txt' file NOT FOUND                                                               
2024.04.27 08:39:15.065   
2024.04.27 08:39:15.065 FINISHED fileEncryption() ::

If you do not want a detailed output log for the fileEncryption() command:

• setKeyFilesDirectory(“C:\\Users\\guest\\ema\\key\\”);
• setEncryptedFilesDirectory(“C:\\Users\\guest\\ema\\msk\\”);
• setOriginFilesDirectory(“C:\\Users\\guest\\ema\\src\\”);
• setKey(“1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key”);
• disableEncryptionDetails();
• fileEncryption(“4000000.txt”, “”);

2024.04.27 08:35:45.960 RUNNING setKeyFilesDirectory() :: 
2024.04.27 08:35:45.964   SETTING 'C:\Users\guest\ema\key\' as input/output keys files directory                     
2024.04.27 08:35:45.965   
2024.04.27 08:35:45.965 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:35:45.965 RUNNING setEncryptedFilesDirectory() :: 
2024.04.27 08:35:45.966   SETTING 'C:\Users\guest\ema\msk\' as output encrypted files directory                      
2024.04.27 08:35:45.966   
2024.04.27 08:35:45.966 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:35:45.966 RUNNING setOriginFilesDirectory() :: 
2024.04.27 08:35:45.967   SETTING 'C:\Users\guest\ema\src\' as origin files directory                                
2024.04.27 08:35:45.967   
2024.04.27 08:35:45.967 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:35:45.967 RUNNING setKeyFilename() :: 
2024.04.27 08:35:45.968   SETTING the key
2024.04.27 08:35:45.968   C:\Users\guest\ema\key\1713795503342556300_RiwfKN66ufGX2LV267ld5U8iDLaDLyaR.key     4.194.304-byte
2024.04.27 08:35:45.968     sub-key_1: from index '0' to index '2.097.151'
2024.04.27 08:35:45.968     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.27 08:35:46.037   
2024.04.27 08:35:46.037   This key adds 30890 random bytes to the top of pre-encryption data if origin data is a file
2024.04.27 08:35:46.037   and 965 random bytes to the top of pre-encryption data if origin data is a byte array      
2024.04.27 08:35:46.037   
2024.04.27 08:35:46.037 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:35:46.037 RUNNING disableEncryptionDetails() :: 
2024.04.27 08:35:46.038   DISABLING details in encryption stage
2024.04.27 08:35:46.038   
2024.04.27 08:35:46.038 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.27 08:35:46.038 RUNNING fileEncryption() :: 
2024.04.27 08:35:46.038   FILE TO ENCRYPT
2024.04.27 08:35:46.038   C:\Users\guest\ema\src\4000000.txt                                                  4.000.000-byte
2024.04.27 08:35:46.039   ..................................................................................................
2024.04.27 08:35:46.121   SAVING THE ENCRYPTED FILE
2024.04.27 08:35:46.121   C:\Users\guest\ema\msk\1714206946130266400_cOBzmtqrixPkNiWdsWUtb8bCEyac28Ow.msk     4.031.708-byte
2024.04.27 08:35:46.122   
2024.04.27 08:35:46.122 FINISHED fileEncryption() ::

Encrypt a byte array

Encrypting a byte array is similar to encrypting a file, but without the need to set filenames or paths. The method requires a byte array with at least one element, unlike file encryption which can also be empty.

Encrypting a byte array produces a ByteResult object consisting of a boolean result and the encrypted byte array is as follow:

• ByteResult encryption = byteArrayEncryption(byteArray);

the encryption result is:

• encryption.getResult(); // boolean

and the encrypted byte array is:

• encryption.getData(); // byte array

Now the decrypted data must be managed by the user. (see Decrypt a byte array)

Example

• String string = “Hello world”;
• byte[] byteArray = string.getBytes();
• setKeyFilename(“1710489295094854777_IPLLUX88fvtd43MRtj10tPTKJqtpRVJg.key”);
• setEncryptionChecksumAlgorithm(3); // SHA-512
• ByteResult encryption = byteArrayEncryption(byteArray);
• ByteResult decryption = byteArrayDecryption(encryption.getData());
• System.out.println();
• for (byte value : decryption.getData()) { System.out.print((char) value); }

2024.04.04 09:22:52.901 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.04 09:22:52.901 RUNNING setKeyFilename() :: 
2024.04.04 09:22:52.902   SETTING the key
2024.04.04 09:22:52.902   C:\Users\guest\ema\key\1712213110928004300_a7721cd837e1de1e5c0daec15bf4c13fca340142.key
2024.04.04 09:22:52.902   Size = 55.556-byte
2024.04.04 09:22:52.904     sub-key_1: from index '0' to index '2.097.151'
2024.04.04 09:22:52.904     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.04 09:22:52.906   
2024.04.04 09:22:52.907   This key adds 10297 random bytes to the top of pre-encryption data if origin data is a file
2024.04.04 09:22:52.907   and 321 random bytes to the top of pre-encryption data if origin data is a byte array    
2024.04.04 09:22:52.908   
2024.04.04 09:22:52.908 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.04 09:22:52.909 RUNNING setEncryptionChecksumAlgorithm() :: 
2024.04.04 09:22:52.909   SETTING checksum algorithm to 'SHA-256' for encryption
2024.04.04 09:22:52.909   
2024.04.04 09:22:52.909 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.04 09:22:52.910 RUNNING byteArrayEncryption() :: 
2024.04.04 09:22:52.913   ENCRYPTING A BYTE ARRAY
2024.04.04 09:22:52.913    Size = 11-byte
2024.04.04 09:22:52.913   ..................................................................................................
2024.04.04 09:22:52.913   ENCRYPTION KEY
2024.04.04 09:22:52.914   C:\Users\guest\ema\key\1712213110928004300_a7721cd837e1de1e5c0daec15bf4c13fca340142.key
2024.04.04 09:22:52.914   Size = 55.556-byte
2024.04.04 09:22:52.915     sub-key_1: from index '0' to index '2.097.151'
2024.04.04 09:22:52.914     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.04 09:22:52.915   
2024.04.04 09:22:52.915   This key adds 10297 random bytes to the top of pre-encryption data if origin data is a file
2024.04.04 09:22:52.917   and 321 random bytes to the top of pre-encryption data if origin data is a byte array    
2024.04.04 09:22:52.917   ..................................................................................................
2024.04.04 09:22:52.918   ENCRYPTION SETTINGS
2024.04.04 09:22:52.919    Encryption execution core: ENABLED
2024.04.04 09:22:52.919    Checksum calculation: ENABLED with SHA-256 algorithm
2024.04.04 09:22:52.919    Encryption details: ENABLED
2024.04.04 09:22:52.920   ..................................................................................................
2024.04.04 09:22:52.920   STARTING THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.04 09:22:52.920    Reading the prepared byte array                     00000569µs                            11-byte
2024.04.04 09:22:52.923    Encrypting the byte array                           00002680µs
2024.04.04 09:22:52.928    Return the encrypted byte array                     00000023µs                        65.536-byte
2024.04.04 09:22:52.929   FINISHED THE CORE EXECUTION IN ENCRYPTION MODE
2024.04.04 09:22:52.929   ..................................................................................................
2024.04.04 09:22:52.929   The checksum SHA-256 was calculated
2024.04.04 09:22:52.930   Encryption performed successfully
2024.04.04 09:22:52.930   
2024.04.04 09:22:52.930 FINISHED byteArrayEncryption() ::
2024.04.04 09:22:52.931   
2024.04.04 09:22:52.931 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
2024.04.04 09:22:52.931 RUNNING byteArrayDecryption() :: 
2024.04.04 09:22:52.931   DECRYPTING A BYTE ARRAY
2024.04.04 09:22:52.931    Size = 65.536-byte
2024.04.04 09:22:52.932   ..................................................................................................
2024.04.04 09:22:52.932   DECRYPTION KEY
2024.04.04 09:22:52.932   C:\Users\guest\ema\key\1712213110928004300_a7721cd837e1de1e5c0daec15bf4c13fca340142.key
2024.04.04 09:22:52.932   Size = 55.556-byte
2024.04.04 09:22:52.933     sub-key_1: from index '0' to index '2.097.151'
2024.04.04 09:22:52.933     sub-key_2: from index '2.097.152' to index '4.194.304'
2024.04.04 09:22:52.934    Decrypting the byte array                           00000454µs
2024.04.04 09:22:52.934   
2024.04.04 09:22:52.935   This key adds 10297 random bytes to the top of pre-encryption data if origin data is a file
2024.04.04 09:22:52.935   and 321 random bytes to the top of pre-encryption data if origin data is a byte array    
2024.04.04 09:22:52.935   ..................................................................................................
2024.04.04 09:22:52.936   DECRYPTION SETTINGS
2024.04.04 09:22:52.936    Decryption details: ENABLED
2024.04.04 09:22:52.936   ..................................................................................................
2024.04.04 09:22:52.937   STARTING THE CORE EXECUTION IN DECRYPTION MODE
2024.04.04 09:22:52.937    Reading the prepared byte array                     00004605µs                        65.536-byte
2024.04.04 09:22:52.937    > Checksum SHA-256 algorithm found
2024.04.04 09:22:52.937    Calculating SHA-256 checksum                        00000000µs
2024.04.04 09:22:52.938    Return the decrypted byte array                     00000005µs                            11-byte
2024.04.04 09:22:52.938   FINISHED THE CORE EXECUTION IN DECRYPTION MODE
2024.04.04 09:22:52.939   ..................................................................................................
2024.04.04 09:22:52.939   CHECKSUM SHA-256 was verified and is correct
2024.04.04 09:22:52.939   Decryption performed successfully
2024.04.04 09:22:52.940   
2024.04.04 09:22:52.940 FINISHED byteArrayDecryption() ::
2024.04.04 09:22:52.940   
2024.04.04 09:22:52.941 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

Hello world