Struct EncryptedMessage

pub struct EncryptedMessage<T> { /* private fields */ }

A wrapper for a message of type T with support for in-place encryption/decryption.

This struct provides functionality for encrypting and decrypting messages while maintaining a specific format:

[ msg-hdr | additional-data | payload | trailer | tag + nonce ]

Where:

• msg-hdr: Message header containing ID, TTL, and flags
• additional-data: Optional unencrypted data
• payload: The encrypted external representation of type T
• trailer: Optional encrypted variable-sized data
• tag + nonce: Authentication tag and nonce for the encryption scheme

The payload and trailer sections are encrypted, while the header and additional data remain in plaintext.

Implementations

impl<T: AnyBitPattern + NoUninit> EncryptedMessage<T>

pub fn size(ad: usize, trailer: usize, scheme: &dyn EncryptionScheme) -> usize

Calculates the total size of an encrypted message.

Arguments

• ad - Size of additional data in bytes
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use

Returns

The total size in bytes needed for the encrypted message

pub fn new( id: &MsgId, ttl: u32, flags: u16, trailer: usize, scheme: &dyn EncryptionScheme, ) -> Self

Creates a new encrypted message with the specified parameters.

Arguments

• id - Message identifier
• ttl - Time-to-live value
• flags - Message flags
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use

Returns

A new EncryptedMessage instance

pub fn new_with_ad( id: &MsgId, ttl: u32, flags: u16, additional_data: usize, trailer: usize, scheme: &dyn EncryptionScheme, ) -> Self

Creates a new encrypted message with additional data.

Arguments

• id - Message identifier
• ttl - Time-to-live value
• flags - Message flags
• additional_data - Size of additional data in bytes
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use

Returns

A new EncryptedMessage instance with space for additional data

pub fn from_buffer( buffer: Vec<u8>, id: &MsgId, ttl: u32, flags: u16, additional_data: usize, trailer: usize, scheme: &dyn EncryptionScheme, ) -> Self

Creates an encrypted message from an existing buffer.

Arguments

• buffer - Existing buffer to use
• id - Message identifier
• ttl - Time-to-live value
• flags - Message flags
• additional_data - Size of additional data in bytes
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use

Returns

A new EncryptedMessage instance using the provided buffer

pub fn payload_with_ad( &mut self, scheme: &dyn EncryptionScheme, ) -> (&mut T, &mut [u8], &mut [u8])

Returns mutable references to the message payload, trailer, and additional data.

Arguments

• scheme - The encryption scheme to use

Returns

A tuple containing:

• Mutable reference to the payload object
• Mutable reference to the trailer bytes
• Mutable reference to the additional data bytes

pub fn payload(&mut self, scheme: &dyn EncryptionScheme) -> (&mut T, &mut [u8])

Returns mutable references to the message payload and trailer.

Arguments

• scheme - The encryption scheme to use

Returns

A tuple containing:

• Mutable reference to the payload object
• Mutable reference to the trailer bytes

pub fn encrypt( self, scheme: &mut dyn EncryptionScheme, receiver: usize, ) -> Option<Vec<u8>>

Encrypts the message using the provided encryption scheme.

Arguments

• scheme - The encryption scheme to use
• receiver - The ID of the intended receiver

Returns

The encrypted message as a byte vector, or None if encryption failed

pub fn decrypt_with_ad<'msg>( buffer: &'msg mut [u8], additional_data: usize, trailer: usize, scheme: &dyn EncryptionScheme, sender: usize, ) -> Option<(&'msg T, &'msg [u8], &'msg [u8])>

Decrypts a message and returns references to the payload, trailer, and additional data.

Arguments

• buffer - The encrypted message buffer
• additional_data - Size of additional data in bytes
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use
• sender - The ID of the message sender

Returns

A tuple containing references to the decrypted payload, trailer, and additional data, or None if decryption failed

pub fn decrypt<'msg>( buffer: &'msg mut [u8], trailer: usize, scheme: &dyn EncryptionScheme, sender: usize, ) -> Option<(&'msg T, &'msg [u8])>

Decrypts a message and returns references to the payload and trailer.

Arguments

• buffer - The encrypted message buffer
• trailer - Size of trailer data in bytes
• scheme - The encryption scheme to use
• sender - The ID of the message sender

Returns

A tuple containing references to the decrypted payload and trailer, or None if decryption failed