shadow-crypt-core 3.0.0

Core types and deterministic operations for shadow-crypt
Documentation 
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use crate::{
    errors::{FileError, HeaderError},
    file::PlaintextFile,
    memory::SecureKey,
};

use super::header::FileHeader;

/// Represents a complete encrypted file with header and content
#[derive(Debug)]
pub struct EncryptedFile {
    header: FileHeader,
    ciphertext: Vec<u8>,
}

impl EncryptedFile {
    pub fn new(header: FileHeader, ciphertext: Vec<u8>) -> Self {
        Self { header, ciphertext }
    }

    /// Parses a serialized v1 file into its header and content ciphertext.
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, HeaderError> {
        let header = FileHeader::try_deserialize(bytes)?;
        let ciphertext = bytes[header.header_length()..].to_vec();

        Ok(Self::new(header, ciphertext))
    }

    /// Serializes the complete file (header followed by content ciphertext).
    pub fn to_bytes(&self) -> Vec<u8> {
        let mut bytes = self.header.serialize();
        bytes.extend_from_slice(&self.ciphertext);
        bytes
    }

    /// Decrypts the filename and content. v1 has no header authentication,
    /// so only the AEAD tags of the two ciphertexts are verified.
    pub fn decrypt(&self, key: &SecureKey) -> Result<PlaintextFile, FileError> {
        let filename = self.header.decrypt_filename(key)?;
        let content = self.header.decrypt_content(&self.ciphertext, key)?;

        Ok(PlaintextFile::new(filename, content))
    }

    pub fn header(&self) -> &FileHeader {
        &self.header
    }
    pub fn ciphertext(&self) -> &[u8] {
        &self.ciphertext
    }
}