fix: establish sodiumoxide 0.2.7 compatibility

Author: comawill

src/internal/keys.rs

@@ -555,7 +555,7 @@ pub struct Signature {
 impl Signature {
     pub fn encode<W: Write>(&self, e: &mut Encoder<W>) -> EncodeResult<()> {
         e.object(1)?;
-        e.u8(0).and(e.bytes(&self.sig.0))?;
+        e.u8(0).and(e.bytes(&self.sig.to_bytes()))?;
         Ok(())
     }
 
@@ -567,7 +567,7 @@ impl Signature {
                 0 => uniq!(
                     "Signature::sig",
                     sig,
-                    Bytes64::decode(d).map(|v| sign::Signature(v.array))?
+                    Bytes64::decode(d).map(|v| sign::Signature::from_bytes(&v.array))??
                 ),
                 _ => d.skip()?,
             }

src/internal/types.rs

@@ -90,6 +90,7 @@ pub type DecodeResult<A> = Result<A, DecodeError>;
 #[derive(Debug)]
 pub enum DecodeError {
     Decoder(cbor::DecodeError),
+    SodiumoxideDecoder(sodiumoxide::crypto::sign::Error),
     InvalidArrayLen(usize),
     LocalIdentityChanged(IdentityKey),
     InvalidType(u8, &'static str),
@@ -102,6 +103,7 @@ impl fmt::Display for DecodeError {
     fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
         match *self {
             DecodeError::Decoder(ref e) => write!(f, "CBOR decoder error: {}", e),
+            DecodeError::SodiumoxideDecoder(ref e) => write!(f, "Sodiumoxide decoder error: {}", e),
             DecodeError::InvalidArrayLen(n) => write!(f, "CBOR array length mismatch: {}", n),
             DecodeError::LocalIdentityChanged(_) => write!(f, "Local identity changed"),
             DecodeError::InvalidType(t, ref s) => write!(f, "Invalid type {}: {}", t, s),
@@ -130,3 +132,9 @@ impl From<cbor::DecodeError> for DecodeError {
         DecodeError::Decoder(err)
     }
 }
+
+impl From<sodiumoxide::crypto::sign::Error> for DecodeError {
+    fn from(err: sodiumoxide::crypto::sign::Error) -> DecodeError {
+        DecodeError::SodiumoxideDecoder(err)
+    }
+}