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# JSON Encryption
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Secure JSON encryption and decryption with password protection, supporting multiple encoding formats and versions for secure data storage and transmission.
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## Capabilities
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### JSON Encryption
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Encrypt data to password-protected JSON format.
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```typescript { .api }
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/**
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 * Encrypt data to JSON format with password protection
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 * @param data - Data bytes to encrypt
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 * @param contentType - Array describing content type
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 * @param passphrase - Password for encryption
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 * @returns Encrypted JSON object
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 */
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function jsonEncrypt(data: Uint8Array, contentType: string[], passphrase: string): EncryptedJson;
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/**
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 * Format encrypted data as JSON
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 * @param encoded - Encoded encrypted data
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 * @param contentType - Optional content type array
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 * @returns Formatted encrypted JSON
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 */
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function jsonEncryptFormat(encoded: string, contentType?: string[]): EncryptedJson;
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```
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### JSON Decryption
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Decrypt password-protected JSON data.
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```typescript { .api }
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/**
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 * Decrypt encrypted JSON with passphrase
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 * @param json - Encrypted JSON object
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 * @param passphrase - Password for decryption
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 * @returns Decrypted data bytes
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 */
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function jsonDecrypt(json: EncryptedJson, passphrase: string): Uint8Array;
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/**
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 * Decrypt encrypted data directly
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 * @param encrypted - Encrypted data object
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 * @param passphrase - Password for decryption
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 * @returns Decrypted data bytes
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 */
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function jsonDecryptData(encrypted: EncryptedJson, passphrase: string): Uint8Array;
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```
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## Types
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```typescript { .api }
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type EncryptedJsonVersion = '0' | '1' | '2' | '3';
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type EncryptedJsonEncoding = 'none' | 'scrypt' | 'xsalsa20-poly1305';
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interface EncryptedJsonDescriptor {
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  /** Descriptor for the content */
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  content: string[];
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  /** The encoding (in current/latest versions this is always an array) */
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  type: EncryptedJsonEncoding | EncryptedJsonEncoding[];
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  /** The version of encoding applied */
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  version: EncryptedJsonVersion;
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}
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interface EncryptedJson {
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  /** The encoded string */
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  encoded: string;
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  /** The encoding used */
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  encoding: EncryptedJsonDescriptor;
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}
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```
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## Usage Example
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```typescript
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import { jsonEncrypt, jsonDecrypt } from "@polkadot/util-crypto";
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// Data to encrypt
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const secretData = new TextEncoder().encode("sensitive information");
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const contentType = ["pkcs8", "sr25519"];
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const passphrase = "strong-password";
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// Encrypt data
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const encrypted = jsonEncrypt(secretData, contentType, passphrase);
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console.log(encrypted.encoding.version); // Current version
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console.log(encrypted.encoding.type); // Encoding methods used
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// Decrypt data
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const decrypted = jsonDecrypt(encrypted, passphrase);
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const decryptedText = new TextDecoder().decode(decrypted);
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console.log(decryptedText); // "sensitive information"
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```
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## Security Features
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- **Password-based encryption** using Scrypt key derivation
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- **XSalsa20-Poly1305** authenticated encryption
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- **Version support** for format evolution
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- **Content type metadata** for proper handling
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- **Salt and nonce generation** for unique encryptions