tunjos / java-crypto-utils

Java Cryptographic, Encoding and Hash Utilities

Java-Crypto-Utils

Java Cryptographic, Encoding and Hash Utilities

• CryptoUtils.java
• EncodingUtils.java
• HashUtils.java

Build: Maven

Install Maven

sudo apt install maven

To run the unit tests:

mvn test

Encryption/Decryption Algorithms - Descriptions

Term	Description
AES	Advanced Encryption Standard
Encryption	The process of encoding information making in away that makes it unreadable for unauthorized users. Plaintext -> Ciphertext
Decryption	The reverse process of encryption. It is the process of decoding the data which has been encrypted making it readable for authorized users. Ciphertext -> Plaintext
Cryptographic key/Key	Is a piece of information (a parameter) that determines the functional output of a cryptographic algorithm.
RSA	Rivest-Shamir-Adleman (Surnames of the creators)
Symmetric Cryptography/Symmetric-Key Cryptography	Makes use of the same cryptographic keys for both encryption of plaintext and decryption of ciphertext.
Asymmetric Cryptography/Public-Key Cryptography	Makes use of different cryptographic keys(pair of public and private keys) used for encryption of plaintext and decryption of ciphertext.
Public Key	A key that is available to the public.
Private Key	A key that is private and known only to the owner.
Cipher/Cypher	An algorithm for performing encryption or decryption.
Plaintext/Cleartext	An unencrypted information pending input into a cryptographic algorithm.
Ciphertext	The result of encryption performed on plaintext using an algorithm - Cipher.
Block Size	The length of the fixed length string of bits operated on by a Block Cipher. Both the input (plaintext) and output (ciphertext) are of the same length.
Key Size/Key Length	The number of bits in a key used by a cryptographic algorithm.
Rounds	In Block Ciphers, the number of times a cipher transformation is repeated over a block of plaintext to create a block of ciphertext. The number of rounds is determined by the key size/ key length.
Block Cipher	A Symmetric-Key Cipher which operates on a groups of bits of fixed length, called blocks.
Block Cipher Mode of Operation	Is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. It describes how to repeatedly apply a cipher's single-block operation to securely transform amounts of data larger than a block.
Common Block Cipher Modes of Operation	ECB(Electronic Codebook), CBC(Cipher Block Chaining), PCBC(Propagating CBC[Cipher Block Chaining]), CFB(Cipher Feedback), OFB(Output Feedback), CTR(Counter)
Broken	When brute-force attack is feasible i.e A key with a given key size can be permutated in feasible time to generate a key that correctly decrypts a Ciphertext.
Brute-force attack	When an attacker guesses many keys with the hope of eventually guessing correctly usually using a supercomputer.

Encryption/Decryption Algorithms - Symmetric

• AES Variants: AES-128, AES-192, AES-256
  Key sizes: 128 bits, 192 bits, 256 bits
  Block Size: 128 bits
  Rounds: 10, 12 or 14 (depending on key size)

Encryption/Decryption Algorithms - Asymmetric

• RSA
  Key sizes: 1,024 to 4,096 bit typical
  Rounds: 1

Hash Functions - Descriptions

Term	Description
MD5	Message-Digest Algorithm
SHA-1	Secure Hash Algorithm 1
SHA-2	Secure Hash Algorithm 2
SHA-3	Secure Hash Algorithm 3
HMAC	Keyed-Hash Message Authentication Code or Hash-Based Message Authentication Code
Cryptographic Hash function	A mathematical algorithm that maps data of arbitrary size to a bit string of a fixed size (a digest/hash) and is designed to be a one-way function - a function which is infeasible to invert.
Digest/Hash	The output of a Cryptographic Hash function.
Digest Size	The size of the output of a Cryptographic Hash function.
Block Size	The length of the fixed length string of bits operated on by a Cryptographic Hash function.
Rounds	In Cryptographic Hash functions, the number of times a digest transformation stage is repeated over a block of plaintext to create a digest.
Salt	Random data that is used as an additional input to a one-way function(Cryptographic Hash functions) that "hashes" data, a password or passphrase.
Data Integrity	Is the maintenance of, and the assurance of the accuracy and consistency of, data over its entire life-cycle.
Authentication	Guarantees that a message has not been modified while in transit (data integrity) and that the receiving party can verify the source of the message.
Broken	When a collision is found. i.e two different inputs generate the same hash usually using a supercomputer.

Hash Functions

• MD5
  Digest Size: 128 bit
  Block Size: 512 bit
  Rounds: 4/64 (depending of Point of View)
  Broken: Yes

• SHA-1
  Digest Size: 160 bit
  Block Size: 512 bit
  Rounds: 80
  Broken: Yes

• SHA-2
  Variants: SHA224, SHA256, SHA384, SHA512, SHA-512/224, SHA-512/256 Digest Size: [SHA-224: 224 bit], [SHA-256: 256 bit], [SHA-384: 384 bit], [SHA-512: 512 bit], [SHA-512/224: 224 bit], [SHA-512/256: 224 bit]
  Block Size: [SHA-224,SHA-256: 512 bit], [SHA-384,SHA-512,SHA-512/224,SHA-512/256: 1024 bit_]
  Rounds: [SHA-224,SHA-256: 64], [SHA-384,SHA-512,SHA-512/224,SHA-512/256: 80]
  Broken: No

• SHA-3
  Variants: SHA3-224, SHA3-256, SHA3-384, SHA3-512, SHAKE128, SHAKE256
  Digest Size: [SHA3-224: 224 bit], [SHA3-256: 256 bit], [SHA3-384: 384 bit], [SHA3-512: 512 bit], [SHAKE128,SHAKE256: d (arbitrary) bit]
  Block Size: [SHA3-224: 1152 bit], [SHA3-256: 1088 bit], [SHA3-384: 832 bit], [SHA3-512: 576 bit], [SHAKE128: 1344 bit], [SHAKE256: 1088 bit]
  Rounds: 24
  Broken: No

HMAC Functions

• HMAC_MD5
• HMAC_SHA1
• HMAC_SHA256
• HMAC_SHA512

Encoding Algorithms - Descriptions

Term	Description
Binary-to-text Encoding	Encoding of data in plaintext. More precisely, it is an encoding of binary data(bytes/bits) in a sequence of printable characters.
Base64	A group of similar binary-to-text encoding schemes that represent binary data in an ASCII string format by translating it into a radix-64 representation. Each Base64 digit represents exactly 6 bits of data. Three 8-bit bytes (i.e., a total of 24 bits) can therefore be represented by four 6-bit Base64 digits.
URL encoding/Percent-encoding	A mechanism for encoding information in a Uniform Resource Identifier (URI) under certain circumstances.

Encoding Algorithms

• Base64

• URL encoding

  Note: A hash function is not an encryption/decryption function.

License

Copyright THIS YEAR tunjos

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

java-crypto-utils's Issues

CrypoUtils.generateAESKey() returns constant String"AES"

java-crypto-utils/src/main/java/co/tunjos/crypto/crypto/CryptoUtils.java

Line 42 in 54b44eb

return ALGORITHM_AES;

The test does not catch this flaw.