More slicing

src/key.rs

@@ -16,9 +16,7 @@
 //! Public/Private keys
 
 use std::intrinsics::copy_nonoverlapping;
-use std::cmp;
-use std::fmt;
-use std::ops;
+use std::{cmp, fmt, ops};
 use rand::Rng;
 use serialize::{Decoder, Decodable, Encoder, Encodable};
 
@@ -534,7 +532,7 @@ impl fmt::Debug for SecretKey {
 #[cfg(test)]
 mod test {
     use serialize::hex::FromHex;
-    use std::rand::thread_rng;
+    use rand::thread_rng;
 
     use test::Bencher;
 
@@ -579,19 +577,19 @@ mod test {
         let mut s = Secp256k1::new().unwrap();
 
         let (sk1, pk1) = s.generate_keypair(true);
-        assert_eq!(SecretKey::from_slice(sk1.as_slice()), Ok(sk1));
-        assert_eq!(PublicKey::from_slice(pk1.as_slice()), Ok(pk1));
+        assert_eq!(SecretKey::from_slice(&sk1[..]), Ok(sk1));
+        assert_eq!(PublicKey::from_slice(&pk1[..]), Ok(pk1));
 
         let (sk2, pk2) = s.generate_keypair(false);
-        assert_eq!(SecretKey::from_slice(sk2.as_slice()), Ok(sk2));
-        assert_eq!(PublicKey::from_slice(pk2.as_slice()), Ok(pk2));
+        assert_eq!(SecretKey::from_slice(&sk2[..]), Ok(sk2));
+        assert_eq!(PublicKey::from_slice(&pk2[..]), Ok(pk2));
     }
 
     #[test]
     fn nonce_slice_round_trip() {
         let mut rng = thread_rng();
         let nonce = Nonce::new(&mut rng);
-        assert_eq!(Nonce::from_slice(nonce.as_slice()), Ok(nonce));
+        assert_eq!(Nonce::from_slice(&nonce[..]), Ok(nonce));
     }
 
     #[test]
@@ -642,12 +640,12 @@ mod test {
 
         // "%x" % rfc6979.generate_k(SECP256k1.generator, sk, hashlib.sha512, hashlib.sha512('').digest())
         let nonce = Nonce::deterministic(&[], &sk);
-        assert_eq!(nonce.as_slice(),
+        assert_eq!(&nonce[..],
                    hex_slice!("d954eddd184cac2b60edcd0e6be9ec54d93f633b28b366420d38ed9c346ffe27"));
 
         // "%x" % rfc6979.generate_k(SECP256k1.generator, sk, hashlib.sha512, hashlib.sha512('test').digest())
         let nonce = Nonce::deterministic(b"test", &sk);
-        assert_eq!(nonce.as_slice(),
+        assert_eq!(&nonce[..],
                    hex_slice!("609cc24acce2f19e46e38a82afc56c1745dee16e04f2b27e24999e1fefeb08bd"));
 
         // # Decrease the secret key by one
@@ -656,12 +654,12 @@ mod test {
 
         // "%x" % rfc6979.generate_k(SECP256k1.generator, sk, hashlib.sha512, hashlib.sha512('').digest())
         let nonce = Nonce::deterministic(&[], &sk);
-        assert_eq!(nonce.as_slice(),
+        assert_eq!(&nonce[..],
                    hex_slice!("9f45f8d0a28e8956673c8da6db3db86ca4f172f0a2dbd62364fdbf786c7d96df"));
 
         // "%x" % rfc6979.generate_k(SECP256k1.generator, sk, hashlib.sha512, hashlib.sha512('test').digest())
         let nonce = Nonce::deterministic(b"test", &sk);
-        assert_eq!(nonce.as_slice(),
+        assert_eq!(&nonce[..],
                    hex_slice!("355c589ff662c838aee454d62b12c50a87b7e95ede2431c7cfa40b6ba2fddccd"));
     }
 

src/secp256k1.rs

@@ -43,7 +43,7 @@ extern crate libc;
 extern crate rand;
 
 use std::intrinsics::copy_nonoverlapping;
-use std::io;
+use std::{io, ops};
 use std::sync::{Once, ONCE_INIT};
 use libc::c_int;
 use rand::{OsRng, Rng, SeedableRng};
@@ -84,13 +84,6 @@ impl Signature {
         data.as_mut_ptr()
     }
 
-    /// Converts the signature to a byte slice suitable for verification
-    #[inline]
-    pub fn as_slice<'a>(&'a self) -> &'a [u8] {
-        let &Signature(len, ref data) = self;
-        &data[..len]
-    }
-
     /// Returns the length of the signature
     #[inline]
     pub fn len(&self) -> usize {
@@ -115,6 +108,46 @@ impl Signature {
     }
 }
 
+impl ops::Index<usize> for Signature {
+    type Output = u8;
+
+    #[inline]
+    fn index(&self, index: usize) -> &u8 {
+        let &Signature(_, ref dat) = self;
+        &dat[index]
+    }
+}
+
+impl ops::Index<ops::Range<usize>> for Signature {
+    type Output = [u8];
+
+    #[inline]
+    fn index(&self, index: ops::Range<usize>) -> &[u8] {
+        let &Signature(_, ref dat) = self;
+        &dat[index.start..index.end]
+    }
+}
+
+impl ops::Index<ops::RangeFrom<usize>> for Signature {
+    type Output = [u8];
+
+    #[inline]
+    fn index(&self, index: ops::RangeFrom<usize>) -> &[u8] {
+        let &Signature(_, ref dat) = self;
+        &dat[index.start..]
+    }
+}
+
+impl ops::Index<ops::RangeFull> for Signature {
+    type Output = [u8];
+
+    #[inline]
+    fn index(&self, _: ops::RangeFull) -> &[u8] {
+        let &Signature(_, ref dat) = self;
+        &dat[..]
+    }
+}
+
 /// An ECDSA error
 #[derive(PartialEq, Eq, Clone, Debug)]
 pub enum Error {
@@ -245,7 +278,7 @@ impl Secp256k1 {
     /// Use `verify_raw` instead.
     #[inline]
     pub fn verify(msg: &[u8], sig: &Signature, pk: &key::PublicKey) -> Result<()> {
-        Secp256k1::verify_raw(msg, sig.as_slice(), pk)
+        Secp256k1::verify_raw(msg, &sig[..], pk)
     }
 
     /// Checks that `sig` is a valid ECDSA signature for `msg` using the public