cmail_rpgp/packet/
compressed_data.rs

1use std::io::{self, Read};
2
3use byteorder::WriteBytesExt;
4use flate2::read::{DeflateDecoder, ZlibDecoder};
5
6use crate::errors::Result;
7use crate::packet::PacketTrait;
8use crate::ser::Serialize;
9use crate::types::{CompressionAlgorithm, Tag, Version};
10
11#[derive(Clone, PartialEq, Eq, derive_more::Debug)]
12pub struct CompressedData {
13    packet_version: Version,
14    compression_algorithm: CompressionAlgorithm,
15    #[debug("{}", hex::encode(compressed_data))]
16    compressed_data: Vec<u8>,
17}
18
19pub enum Decompressor<R> {
20    Uncompressed(R),
21    Zip(DeflateDecoder<R>),
22    Zlib(ZlibDecoder<R>),
23    Bzip2,
24}
25
26impl<'a> Read for Decompressor<&'a [u8]> {
27    fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
28        match self {
29            Decompressor::Uncompressed(ref mut c) => c.read(into),
30            Decompressor::Zip(ref mut c) => c.read(into),
31            Decompressor::Zlib(ref mut c) => c.read(into),
32            Decompressor::Bzip2 => unimplemented!("bzip2"),
33        }
34    }
35}
36
37impl CompressedData {
38    /// Parses a `CompressedData` packet from the given slice.
39    pub fn from_slice(packet_version: Version, input: &[u8]) -> Result<Self> {
40        ensure!(input.len() > 1, "input too short");
41
42        let alg = CompressionAlgorithm::from(input[0]);
43        Ok(CompressedData {
44            packet_version,
45            compression_algorithm: alg,
46            compressed_data: input[1..].to_vec(),
47        })
48    }
49
50    pub fn from_compressed(alg: CompressionAlgorithm, data: Vec<u8>) -> Self {
51        CompressedData {
52            packet_version: Default::default(),
53            compression_algorithm: alg,
54            compressed_data: data,
55        }
56    }
57
58    pub fn decompress(&self) -> Result<Decompressor<&[u8]>> {
59        match self.compression_algorithm {
60            CompressionAlgorithm::Uncompressed => {
61                Ok(Decompressor::Uncompressed(&self.compressed_data[..]))
62            }
63            CompressionAlgorithm::ZIP => Ok(Decompressor::Zip(DeflateDecoder::new(
64                &self.compressed_data[..],
65            ))),
66            CompressionAlgorithm::ZLIB => Ok(Decompressor::Zlib(ZlibDecoder::new(
67                &self.compressed_data[..],
68            ))),
69            CompressionAlgorithm::BZip2 => unimplemented_err!("BZip2"),
70            CompressionAlgorithm::Private10 | CompressionAlgorithm::Other(_) => unsupported_err!(
71                "CompressionAlgorithm {} is unsupported",
72                u8::from(self.compression_algorithm)
73            ),
74        }
75    }
76
77    pub fn compressed_data(&self) -> &[u8] {
78        &self.compressed_data
79    }
80}
81
82impl Serialize for CompressedData {
83    fn to_writer<W: io::Write>(&self, writer: &mut W) -> Result<()> {
84        writer.write_u8(self.compression_algorithm.into())?;
85        writer.write_all(&self.compressed_data)?;
86
87        Ok(())
88    }
89}
90
91impl PacketTrait for CompressedData {
92    fn packet_version(&self) -> Version {
93        self.packet_version
94    }
95
96    fn tag(&self) -> Tag {
97        Tag::CompressedData
98    }
99}
cmail_rpgp/packet/compressed_data.rs

cmail_rpgp/packet/
compressed_data.rs
