Impl Sync and Send for various types

Closes #865

openssl/src/derive.rs

@@ -11,6 +11,9 @@ use pkey::{HasPrivate, HasPublic, PKeyRef};
 /// A type used to derive a shared secret between two keys.
 pub struct Deriver<'a>(*mut ffi::EVP_PKEY_CTX, PhantomData<&'a ()>);
 
+unsafe impl<'a> Sync for Deriver<'a> {}
+unsafe impl<'a> Send for Deriver<'a> {}
+
 impl<'a> Deriver<'a> {
     /// Creates a new `Deriver` using the provided private key.
     ///

openssl/src/hash.rs

@@ -49,6 +49,9 @@ impl MessageDigest {
     }
 }
 
+unsafe impl Sync for MessageDigest {}
+unsafe impl Send for MessageDigest {}
+
 #[derive(PartialEq, Copy, Clone)]
 enum State {
     Reset,
@@ -99,6 +102,9 @@ pub struct Hasher {
     state: State,
 }
 
+unsafe impl Sync for Hasher {}
+unsafe impl Send for Hasher {}
+
 impl Hasher {
     /// Creates a new `Hasher` with the specified hash type.
     pub fn new(ty: MessageDigest) -> Result<Hasher, ErrorStack> {

openssl/src/sign.rs

@@ -85,6 +85,9 @@ pub struct Signer<'a> {
     _p: PhantomData<&'a ()>,
 }
 
+unsafe impl<'a> Sync for Signer<'a> {}
+unsafe impl<'a> Send for Signer<'a> {}
+
 impl<'a> Drop for Signer<'a> {
     fn drop(&mut self) {
         // pkey_ctx is owned by the md_ctx, so no need to explicitly free it.
@@ -244,6 +247,9 @@ pub struct Verifier<'a> {
     pkey_pd: PhantomData<&'a ()>,
 }
 
+unsafe impl<'a> Sync for Verifier<'a> {}
+unsafe impl<'a> Send for Verifier<'a> {}
+
 impl<'a> Drop for Verifier<'a> {
     fn drop(&mut self) {
         // pkey_ctx is owned by the md_ctx, so no need to explicitly free it.

openssl/src/symm.rs

@@ -223,6 +223,9 @@ impl Cipher {
     }
 }
 
+unsafe impl Sync for Cipher {}
+unsafe impl Send for Cipher {}
+
 /// Represents a symmetric cipher context.
 ///
 /// Padding is enabled by default.
@@ -288,6 +291,9 @@ pub struct Crypter {
     block_size: usize,
 }
 
+unsafe impl Sync for Crypter {}
+unsafe impl Send for Crypter {}
+
 impl Crypter {
     /// Creates a new `Crypter`.  The initialisation vector, `iv`, is not necesarry for certain
     /// types of `Cipher`.
@@ -963,7 +969,6 @@ mod tests {
 
     #[test]
     fn test_des_ede3_cbc() {
-
         let pt = "54686973206973206120746573742e";
         let ct = "6f2867cfefda048a4046ef7e556c7132";
         let key = "7cb66337f3d3c0fe7cb66337f3d3c0fe7cb66337f3d3c0fe";