aes-ctr

audio/Cargo.toml

@@ -15,7 +15,7 @@ log = "0.3.5"
 num-bigint = "0.1.35"
 num-traits = "0.1.36"
 tempfile = "2.1"
-aes = "0.1"
+aes-ctr = "0.1.0"
 
 tremor = { git = "https://github.com/plietar/rust-tremor", optional = true }
 vorbis = { version ="0.1.0", optional = true }

audio/src/decrypt.rs

@@ -1,39 +1,38 @@
-use crypto::aes;
-use crypto::symmetriccipher::SynchronousStreamCipher;
-use num_bigint::BigUint;
-use num_traits::FromPrimitive;
 use std::io;
-use std::ops::Add;
+
+use aes_ctr::Aes128Ctr;
+use aes_ctr::stream_cipher::{
+    NewFixStreamCipher, StreamCipherCore, StreamCipherSeek
+};
+use aes_ctr::stream_cipher::generic_array::GenericArray;
 
 use core::audio_key::AudioKey;
 
-const AUDIO_AESIV: &'static [u8] = &[
-    0x72, 0xe0, 0x67, 0xfb, 0xdd, 0xcb, 0xcf, 0x77, 0xeb, 0xe8, 0xbc, 0x64, 0x3f, 0x63, 0x0d, 0x93,
+const AUDIO_AESIV: [u8; 16] = [
+    0x72, 0xe0, 0x67, 0xfb, 0xdd, 0xcb, 0xcf, 0x77,
+    0xeb, 0xe8, 0xbc, 0x64, 0x3f, 0x63, 0x0d, 0x93,
 ];
 
 pub struct AudioDecrypt<T: io::Read> {
-    cipher: Box<SynchronousStreamCipher + 'static>,
-    key: AudioKey,
+    cipher: Aes128Ctr,
     reader: T,
 }
 
 impl<T: io::Read> AudioDecrypt<T> {
     pub fn new(key: AudioKey, reader: T) -> AudioDecrypt<T> {
-        let cipher = aes::ctr(aes::KeySize::KeySize128, &key.0, AUDIO_AESIV);
-        AudioDecrypt {
-            cipher: cipher,
-            key: key,
-            reader: reader,
-        }
+        let cipher = Aes128Ctr::new(
+            &GenericArray::from_slice(&key.0),
+            &GenericArray::from_slice(&AUDIO_AESIV),
+        );
+        AudioDecrypt { cipher, reader }
     }
 }
 
 impl<T: io::Read> io::Read for AudioDecrypt<T> {
     fn read(&mut self, output: &mut [u8]) -> io::Result<usize> {
-        let mut buffer = vec![0u8; output.len()];
-        let len = try!(self.reader.read(&mut buffer));
+        let len = try!(self.reader.read(output));
 
-        self.cipher.process(&buffer[..len], &mut output[..len]);
+        self.cipher.apply_keystream(&mut output[..len]);
 
         Ok(len)
     }
@@ -42,17 +41,9 @@ impl<T: io::Read> io::Read for AudioDecrypt<T> {
 impl<T: io::Read + io::Seek> io::Seek for AudioDecrypt<T> {
     fn seek(&mut self, pos: io::SeekFrom) -> io::Result<u64> {
         let newpos = try!(self.reader.seek(pos));
-        let skip = newpos % 16;
 
-        let iv = BigUint::from_bytes_be(AUDIO_AESIV)
-            .add(BigUint::from_u64(newpos / 16).unwrap())
-            .to_bytes_be();
-        self.cipher = aes::ctr(aes::KeySize::KeySize128, &self.key.0, &iv);
+        self.cipher.seek(newpos);
 
-        let buf = vec![0u8; skip as usize];
-        let mut buf2 = vec![0u8; skip as usize];
-        self.cipher.process(&buf, &mut buf2);
-
-        Ok(newpos as u64)
+        Ok(newpos)
     }
 }

audio/src/lib.rs

@@ -8,6 +8,7 @@ extern crate byteorder;
 extern crate num_bigint;
 extern crate num_traits;
 extern crate tempfile;
+extern crate aes_ctr;
 
 extern crate librespot_core as core;