IT-Security

Ref.

• https://www.learninjava.com/easy-guide-to-ssl/
• https://badssl.com/
• https://www.learninjava.com/convert-p12-to-jks-and-pem-to-jks/

hashing

Cryptographic Hash Functions (for Security & Authentication)

• MD5 – 128-bit hash (not secure, but still used for checksums)
• SHA-1 – 160-bit hash (deprecated for security purposes)
• SHA-2 (includes multiple versions):
  • SHA-224 – 224-bit
  • SHA-256 – 256-bit (widely used, secure)
  • SHA-384 – 384-bit
  • SHA-512 – 512-bit
• SHA-3 – Modern alternative to SHA-2, available in different sizes
• BLAKE2 – Faster and more secure than SHA-2 (BLAKE2b, BLAKE2s)
• BLAKE3 – Even faster and more efficient than BLAKE2

Password Hashing Algorithms (for Secure Password Storage)

• bcrypt – Adaptive hashing function with salt (widely used for passwords)
• scrypt – Memory-intensive, better resistance against brute-force attacks
• Argon2 – Winner of the "Password Hashing Competition," secure and efficient

Non-Cryptographic Hash Functions (for Fast Hashing)

• CRC32 – 32-bit checksum (used for file integrity checks)
• MurmurHash – Very fast hash function for hash tables
• CityHash – Optimized for speed in large datasets
• xxHash – Extremely fast hash function for streaming data

Cryptographic (Keys & Certificates)

• SSL & TLS are the same. SSL is the old name. TLS is the updated version of SSL.
• X.509 Certificates encoding formats and file extensions.
• (PKCS) Public Key Cryptography Standards >>> are binary files. These are the newer format of .pfx files. #12 is the 12th version of the standard.
• (PEM) Privacy Enhanced Mail >>> are text file alternative to PKCS format.
• We can use .pem for all artifacts. It is recommended to use for certificate (.cer, .crt) and for public or private keys (.key).

* Base64-ASCII: PEM >>> *.pem, *.crt, *.cer, *.key
* Base64-ASCII: PKCS#7 >>> *.p7b, *.p7c
* Binary: DER >>> *.der, *.cer
* Binary: PKCS#12 >>> *.pfx, *.p12

KeyStore/TrustStore

• KeyStore: holds onto certificates that identify us.
• TrustStore: holds onto certificates that identify others.
• Until Java 8, the default KeyStore-Format is JKS. Since Java 9, the default KeyStore-Format is PKCS12.
• Java has bundled a TrustStore called cacerts and it resides in the $JAVA_HOME/jre/lib/security directory

* Certificate: .crt, .pem
* Certificate Chain: .crt, .cer, .pem
* Public Key: .key, .pem
* Private Key: .key, .pem

Converting SSL

• https://cheapsslsecurity.com/ssltools/ssl-converter.php