EC Cryptography Tutorials - Herong's Tutorial Examples
This EC (Elliptic Curve) cryptography tutorial book is a collection of notes and sample codes written by the author while he was learning cryptography technologies himself. Topics include rule of chord and point addition on elliptic curves; Abelian groups with additive and multiplicative notations; ... 2019-01-01, 272👍, 1💬
RSA Public Key Encryption Algorithm
This section describes the RSA public key encryption algorithm. Generating public and private keys used in RSA encryption requires two large prime numbers. 2016-11-21, 120👍, 1💬
DES Encryption Operation Modes
This chapter provides tutorial examples and notes about DES encryption operation modes. Topics include how different blocks of plaintext can be coupled together to improve the strength of the DES encryption algorithm; ECB (Electronic CodeBook), CBC (Cipher Block Chaining), CFB (Cipher FeedBack), and... 2016-11-12, 446👍, 1💬
SHA1 Mesasge Digest Algorithm
This chapter provides tutorial notes and example codes on the SHA1 message digest algorithm. Topics include SHA1 algorithm overview; using SHA1 in Java, PHP, and Perl. 2016-11-05, 1500👍, 5💬
What Is Block Cipher?
This section describes what is block cipher - An encryption scheme in which 'the clear text is broken up into blocks of fixed length, and encrypted one block at a time'. 2016-09-26, 311👍, 1💬
"openssl pkcs8" Converting Keys to PKCS#8 Format
This section provides a tutorial example on how to convert a private key file from the traditional format into PKCS#8 format using the 'openssl pkcs8' command. Keys can still be encoded with DER or PEM with or without DES encryption in PKCS#8 format. 2016-04-12, 5440👍, 1💬
Certificate X.509 Standard and DER/PEM Formats
This chapter provides tutorial notes and example codes on certificate content standard and file formats. Topics include X.509 standard for certificate content; DER encoding for certificate binary file format; PEM encoding for certificate text file format; exchanging certificates in DER and PEM forma... 2016-04-10, 130👍, 1💬
Summary - Migrating "keystore" Keys to "OpenSSL"
This section describes high level steps on how to migrate a private key generated in a JKS (Java KeyStore) file to an 'OpenSSL' key file. The key step is to convert a JKS file into a PKCS#12 file with 'keytool'. 2016-04-09, 102👍, 1💬
Certificate in PEM Format
This section describes what is certificate PEM (Privacy Enhanced Mail) format - A format uses PEM idea to convert a certificate in DER format to a message of printable characters. The conversion uses the Base64 encoding. 2016-03-30, 3282👍, 2💬
Key Schedule (Sub-Keys Generation) Algorithm
This section describes the Blowfish Key Schedule (Sub-Keys Generation) algorithm. It uses the binary representation of the fractional portion of constant Pi - 3.1415927... as initial values. 2016-03-17, 1111👍, 2💬
Viewing Components of RSA Keys
This section provides a tutorial example on how to view different components of a pair of RSA private key and public key using the OpenSSL command line tool. 2016-03-14, 1663👍, 2💬
Viewing Components of Certificate Signing Request
This section provides a tutorial example on how to view different components of a CSR (Certificate Signing Request) for your public key with OpenSSL. 2016-03-14, 600👍, 3💬
Key Pair Sample Program - JcaKeyPair.java
This section provides a tutorial example on how to write simple program to generate a pair of private key and public key for the RSA or DSA algorithm. 2016-03-01, 852👍, 1💬
RSA Implementation using java.math.BigInteger Class
This chapter provides tutorial notes and example codes on RSA implementation using Java BigInteger class. Topics include introduction of the java.math.BigInteger class; generating large probable prime numbers; generating RSA public key and private key; validating RSA keys; determining cleartext and ... 2016-02-29, 2680👍, 3💬
Steps of Using DES Algorithm in JDK JCE
This section describes how to use DES algorithm provided in the JDK JCE package. Steps include building a secret key object from key material; creating and initializing a cipher object. 2016-01-24, 731👍, 1💬
What is ECB (Electronic CodeBook) Operation Mode?
This section describes what is ECB (Electronic CodeBook) Operation Mode - each plaintext block is encrypted independently without any input from other blocks. 2016-01-10, 2600👍, 2💬
Introduction to AES (Advanced Encryption Standard)
Tutorial notes and example codes on AES algorithms. Topics include introduction of AES (Advanced Encryption Standard); AES encryption algorithm; AES key schedule (round keys) algorithm and illustration example; MixColumns procedure algorithm; AES decryption algorithms. 2015-11-27, 258👍, 1💬
What is OFB (Output FeedBack) Operation Mode?
This section describes what is OFB (Output FeedBack) Operation Mode - each plaintext block is XORed with the current output block to be the ciphertext block. The current output block is the encrypted version of the previous output block. 2015-11-13, 1448👍, 2💬
This section provides a quick introduction of the SecretKeySpec class and the KeySpec interface. The...
This section describes steps of the compilation and execution process of C programs: preprocessing, ...
This section provides a tutorial example on how to create and delete a program service with 'sc.exe'...
This section provides a quick description of the Services Console and a tutorial example on how to l...
This web site provides a collection of about 40 free tutorial books on programming languages, Web ap...