tool: Implement compression and padding.

4 files changed, 36 insertions, 4 deletions

diff --git a/tool/src/commands/mod.rs b/tool/src/commands/mod.rs
index 229a6854..0db911ce 100644
--- a/tool/src/commands/mod.rs
+++ b/tool/src/commands/mod.rs
@@ -8,7 +8,10 @@ use rpassword;
 
 extern crate sequoia_openpgp as openpgp;
 use sequoia_core::Context;
-use crate::openpgp::constants::DataFormat;
+use crate::openpgp::constants::{
+    CompressionAlgorithm,
+    DataFormat,
+};
 use crate::openpgp::crypto;
 use crate::openpgp::{TPK, KeyID, Result};
 use crate::openpgp::packet::prelude::*;
@@ -22,6 +25,11 @@ use crate::openpgp::parse::stream::{
 };
 use crate::openpgp::serialize::stream::{
     Message, Signer, LiteralWriter, Encryptor, EncryptionMode,
+    Compressor,
+};
+use crate::openpgp::serialize::padding::{
+    Padder,
+    padme,
 };
 extern crate sequoia_store as store;
 
@@ -80,7 +88,8 @@ fn get_signing_keys(tpks: &[openpgp::TPK])
 pub fn encrypt(store: &mut store::Store,
                input: &mut io::Read, output: &mut io::Write,
                npasswords: usize, recipients: Vec<&str>,
-               mut tpks: Vec<openpgp::TPK>, signers: Vec<openpgp::TPK>)
+               mut tpks: Vec<openpgp::TPK>, signers: Vec<openpgp::TPK>,
+               compression: &str)
                -> Result<()> {
     for r in recipients {
         tpks.push(store.lookup(r).context("No such key found")?.tpk()?);
@@ -114,6 +123,18 @@ pub fn encrypt(store: &mut store::Store,
                                   None, None)
         .context("Failed to create encryptor")?;
 
+    match compression {
+        "none" => (),
+        "pad" => sink = Padder::new(sink, padme)?,
+        "zip" =>
+            sink = Compressor::new(sink, CompressionAlgorithm::Zip, None)?,
+        "zlib" =>
+            sink = Compressor::new(sink, CompressionAlgorithm::Zlib, None)?,
+        "bzip2" =>
+            sink = Compressor::new(sink, CompressionAlgorithm::BZip2, None)?,
+        _ => unreachable!("all possible choices are handled")
+    }
+
     // Optionally sign message.
     if ! signers.is_empty() {
         sink = Signer::with_intended_recipients(
diff --git a/tool/src/sq-usage.rs b/tool/src/sq-usage.rs
index 0b25be37..c5580112 100644
--- a/tool/src/sq-usage.rs
+++ b/tool/src/sq-usage.rs
@@ -76,6 +76,8 @@
 //!     -V, --version      Prints version information
 //!
 //! OPTIONS:
+//!         --compression <KIND>                  Selects compression scheme to use [default: pad]  [possible values: none,
+//!                                               pad, zip, zlib, bzip2]
 //!     -o, --output <FILE>                       Sets the output file to use
 //!     -r, --recipient <LABEL>...                Recipient to encrypt for (can be given multiple times)
 //!         --recipient-key-file <TPK-FILE>...    Recipient to encrypt for, given as a file (can be given multiple times)
diff --git a/tool/src/sq.rs b/tool/src/sq.rs
index a87c176f..9962a0a4 100644
--- a/tool/src/sq.rs
+++ b/tool/src/sq.rs
@@ -208,7 +208,8 @@ fn real_main() -> Result<(), failure::Error> {
                 .unwrap_or(Ok(vec![]))?;
             commands::encrypt(&mut store, &mut input, &mut output,
                               m.occurrences_of("symmetric") as usize,
-                              recipients, additional_tpks, additional_secrets)?;
+                              recipients, additional_tpks, additional_secrets,
+                              m.value_of("compression").expect("has default"))?;
         },
         ("sign",  Some(m)) => {
             let mut input = open_or_stdin(m.value_of("input"))?;
diff --git a/tool/src/sq_cli.rs b/tool/src/sq_cli.rs
index 6042efcb..feb9d755 100644
--- a/tool/src/sq_cli.rs
+++ b/tool/src/sq_cli.rs
@@ -111,7 +111,15 @@ pub fn build() -> App<'static, 'static> {
                          .short("s")
                          .multiple(true)
                          .help("Encrypt with a password \
-                                (can be given multiple times)")))
+                                (can be given multiple times)"))
+                    .arg(Arg::with_name("compression")
+                         .value_name("KIND")
+                         .long("compression")
+                         .possible_values(&["none", "pad", "zip", "zlib",
+                                            "bzip2"])
+                         .default_value("pad")
+                         .help("Selects compression scheme to use")))
+
         .subcommand(SubCommand::with_name("sign")
                     .display_order(25)
                     .about("Signs a message")