1. What is neoCrypto?

neoCrypto is a native, comprehensive cryptographic toolkit for VisualNEO Win.

It provides authenticated AES-256 encryption, cryptographic hashing (MD5, SHA-1, SHA-256, SHA-384, SHA-512 and standard CRC-32), HMAC creation and verification, Base64/Hex/URL encoders, cryptographically secure random bytes and passwords, and UUID creation.

Version 2 uses the authenticated NC257 container for text and files. A password is expanded with PBKDF2-HMAC-SHA-256 (100,000 iterations) into independent encryption and authentication keys. The ciphertext is verified with HMAC-SHA-256 before any plaintext is returned or written. Version 2 intentionally does not decrypt the unauthenticated NC256 format.

Why do you need neoCrypto?

Protect Sensitive Data: Encrypt local records or documents so that corruption, a wrong password, and deliberate modification are detected before decryption.
Verify File & Data Integrity: Generate SHA-256 or MD5 checksums for files to detect corruption or tampering after downloads.
Interact with Web APIs: Encode query parameters for URLs, convert binary payloads to Base64, and calculate HMAC-SHA256 signatures required by cloud REST APIs.
Generate Secure Keys & Tokens: Create UUID v4 identifiers and high-entropy passwords with custom character sets.

2. Quick Start: Everyday Cryptography in 3 Steps

Step 1: Encrypt and Decrypt a Text String with AES-256

TEXT

. Encrypt secret text with your password
neoCryptoEncryptString "Super Secret Database Password" "MyKey@2026" "[EncryptedBase64]"
. [EncryptedBase64] -> "Y6WXh6QHfOnQheZTyQwiH4frJRiJwpulgvIO41XM..."

. Decrypt it back
neoCryptoDecryptString "[EncryptedBase64]" "MyKey@2026" "[DecryptedText]"
AlertBox "Decrypted" "[DecryptedText]"

Step 2: Calculate a SHA-256 Hash

TEXT

. Hash a string (one-way cryptographic digest)
neoCryptoHashString "SHA256" "Hello VisualNEO" "[HashResult]"
. [HashResult] -> "a35d8869b35b602ec45c0f..."

. Hash a downloaded file to verify integrity
neoCryptoHashFile "SHA256" "[PubDir]setup.exe" "[FileHash]"

Step 3: Base64 and URL Encoding

TEXT

. Convert text to Base64
neoCryptoBase64Encode "User:Admin" "[AuthHeader]"

. Percent-encode text for URL queries
neoCryptoUrlEncode "Search term with spaces & symbols" "[SafeUrlParam]"

3. Real-World Practical Examples

Example 1: Encrypting Application Data Files to Disk

Protect sensitive local save files:

TEXT

. Encrypt the database before exiting application
neoCryptoEncryptFile "[PubDir]app_data.db" "[PubDir]app_data.enc" "StrongAppPassword@2026"
FileErase "[PubDir]app_data.db"

. Upon next startup, restore the data file
neoCryptoDecryptFile "[PubDir]app_data.enc" "[PubDir]app_data.db" "StrongAppPassword@2026"

Example 2: Secure Random Password Generator

Generate strong temporary passwords for users:

TEXT

. Generate a 16-character password with uppercase, lowercase, digits and symbols
neoCryptoGenerateRandomPassword "16" "True" "True" "True" "[NewPassword]"
AlertBox "Generated Password" "[NewPassword]"

Example 3: Generating Unique Database UUIDs

Create a globally unique identifier (UUID v4) for new database records:

TEXT

neoCryptoGenerateUUID "standard" "[RecordUUID]"
. [RecordUUID] -> "3f4b8c92-1e7a-4b0d-9c3f-8a2b5e1c4d7e"

Example 4: Calculating HMAC-SHA256 for Cloud API Authentication

Many cloud APIs (AWS, GitHub, Stripe) require HMAC signatures:

TEXT

neoCryptoHMAC "SHA256" "my_api_secret_key" "POST/v1/payment" "[HmacSignature]"
neoCryptoVerifyHMAC "SHA256" "my_api_secret_key" "POST/v1/payment" "[HmacSignature]" "[SignatureValid]"

4. Complete Action Reference

Encoders & Decoders

Action	Parameters	Description
`neoCryptoBase64Encode`	`"[Text]"` `"[VarResult]"`	Encodes text string into Base64 format.
`neoCryptoBase64Decode`	`"[Base64Text]"` `"[VarResult]"`	Decodes Base64 string back to UTF-8 text.
`neoCryptoHexEncode`	`"[Text]"` `"[VarResult]"`	Encodes text into Hexadecimal string.
`neoCryptoHexDecode`	`"[HexText]"` `"[VarResult]"`	Decodes Hexadecimal string back to text.
`neoCryptoUrlEncode`	`"[Text]"` `"[VarResult]"`	Percent-encodes text for URLs.
`neoCryptoUrlDecode`	`"[UrlEncodedText]"` `"[VarResult]"`	Decodes URL-encoded text.

Cryptographic Hashes & Signatures

Action	Parameters	Description
`neoCryptoHashString`	`"[Algorithm]"` `"[Text]"` `"[VarResult]"`	Computes hash of string (`MD5`, `SHA1`, `SHA256`, `SHA384`, `SHA512`, `CRC32`).
`neoCryptoHashFile`	`"[Algorithm]"` `"[FilePath]"` `"[VarResult]"`	Computes hash of an entire disk file.
`neoCryptoHmac`	`"[Algorithm]"` `"[SecretKey]"` `"[Text]"` `"[VarResult]"`	Calculates Keyed-Hash Message Authentication Code.
`neoCryptoVerifyHMAC`	`"[Algorithm]"` `"[SecretKey]"` `"[Text]"` `"[ExpectedHex]"` `"[VarValid]"`	Verifies an HMAC using constant-time comparison.

Symmetric Encryption (AES-256)

Action	Parameters	Description
`neoCryptoEncryptString`	`"[Text]"` `"[Password]"` `"[VarResultBase64]"`	Encrypts text using AES-256.
`neoCryptoDecryptString`	`"[CipherBase64]"` `"[Password]"` `"[VarResultText]"`	Decrypts AES-256 ciphertext.
`neoCryptoEncryptFile`	`"[SourceFile]"` `"[DestFile]"` `"[Password]"`	Encrypts a disk file using AES-256.
`neoCryptoDecryptFile`	`"[SourceFile]"` `"[DestFile]"` `"[Password]"`	Decrypts an AES-256 encrypted file.

Utilities & Generators

Action	Parameters	Description
`neoCryptoGenerateRandomPassword`	`"[Length]"` `"[Upper]"` `"[Digits]"` `"[Symbols]"` `"[VarResult]"`	Generates a cryptographically strong random password. Lowercase letters are always included.
`neoCryptoGenerateRandomBytes`	`"[Count]"` `"[hex/base64]"` `"[VarResult]"`	Generates 1 to 1,048,576 cryptographically secure random bytes.
`neoCryptoGenerateUUID`	`"[Format]"` `"[VarResult]"`	Generates a UUID (`standard`, `compact`, `uppercase`, `braced`).

5. Security and Limits

Treat MD5 and SHA-1 as legacy compatibility hashes. Use SHA-256 or stronger for integrity checks.
Encoding is not encryption. Base64, Hex and URL encoding do not protect secrets.
Encrypted source files are limited to 256 MB in this Win32 build to keep memory use bounded.
Decryption writes atomically: authentication failure does not replace the destination file.
Store passwords outside the publication whenever possible. The plugin cannot protect a password embedded in a script.

6. Interactive Demo

Open demo/neoCrypto-demo.pub in VisualNEO Win to test AES-256 string/file encryption, SHA-256 hashes, Base64/Hex conversion, and UUID generation interactively.