From 22f029064a31cb72c71fd43e8c17f75dfc3d9e03 Mon Sep 17 00:00:00 2001
From: Peter Farr <Peter@PrismaPhonic.com>
Date: Mon, 11 Nov 2019 11:09:49 -0800
Subject: [PATCH 1/3] Added clonability for sha hash state.  Useful for
 incremental hashing

---
 openssl-sys/src/sha.rs | 1 +
 openssl/src/sha.rs     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/openssl-sys/src/sha.rs b/openssl-sys/src/sha.rs
index a9e7b15c..2ad91f6f 100644
--- a/openssl-sys/src/sha.rs
+++ b/openssl-sys/src/sha.rs
@@ -5,6 +5,7 @@ pub type SHA_LONG = c_uint;
 pub const SHA_LBLOCK: c_int = 16;
 
 #[repr(C)]
+#[derive(Clone)]
 pub struct SHA_CTX {
     pub h0: SHA_LONG,
     pub h1: SHA_LONG,
diff --git a/openssl/src/sha.rs b/openssl/src/sha.rs
index e3c4c2e8..dffadb90 100644
--- a/openssl/src/sha.rs
+++ b/openssl/src/sha.rs
@@ -110,6 +110,7 @@ pub fn sha512(data: &[u8]) -> [u8; 64] {
 ///
 /// SHA1 is known to be insecure - it should not be used unless required for
 /// compatibility with existing systems.
+#[derive(Clone)]
 pub struct Sha1(ffi::SHA_CTX);
 
 impl Sha1 {

From 8fae1115a4c60a3b51fce706da7bc0092ea8ee7f Mon Sep 17 00:00:00 2001
From: Peter Farr <Peter@PrismaPhonic.com>
Date: Mon, 11 Nov 2019 16:31:47 -0800
Subject: [PATCH 2/3] Changed all sha objects to be clonable per PR review
 suggestion.

---
 openssl-sys/src/sha.rs | 2 ++
 openssl/src/sha.rs     | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/openssl-sys/src/sha.rs b/openssl-sys/src/sha.rs
index 2ad91f6f..e8d1403f 100644
--- a/openssl-sys/src/sha.rs
+++ b/openssl-sys/src/sha.rs
@@ -26,6 +26,7 @@ extern "C" {
 }
 
 #[repr(C)]
+#[derive(Clone)]
 pub struct SHA256_CTX {
     pub h: [SHA_LONG; 8],
     pub Nl: SHA_LONG,
@@ -49,6 +50,7 @@ extern "C" {
 pub type SHA_LONG64 = u64;
 
 #[repr(C)]
+#[derive(Clone)]
 pub struct SHA512_CTX {
     pub h: [SHA_LONG64; 8],
     pub Nl: SHA_LONG64,
diff --git a/openssl/src/sha.rs b/openssl/src/sha.rs
index dffadb90..a33a0f6c 100644
--- a/openssl/src/sha.rs
+++ b/openssl/src/sha.rs
@@ -146,6 +146,7 @@ impl Sha1 {
 }
 
 /// An object which calculates a SHA224 hash of some data.
+#[derive(Clone)]
 pub struct Sha224(ffi::SHA256_CTX);
 
 impl Sha224 {
@@ -181,6 +182,7 @@ impl Sha224 {
 }
 
 /// An object which calculates a SHA256 hash of some data.
+#[derive(Clone)]
 pub struct Sha256(ffi::SHA256_CTX);
 
 impl Sha256 {
@@ -216,6 +218,7 @@ impl Sha256 {
 }
 
 /// An object which calculates a SHA384 hash of some data.
+#[derive(Clone)]
 pub struct Sha384(ffi::SHA512_CTX);
 
 impl Sha384 {
@@ -251,6 +254,7 @@ impl Sha384 {
 }
 
 /// An object which calculates a SHA512 hash of some data.
+#[derive(Clone)]
 pub struct Sha512(ffi::SHA512_CTX);
 
 impl Sha512 {

From 5991f425faacca144c640f7a978883b4b939df75 Mon Sep 17 00:00:00 2001
From: Peter Farr <Peter@PrismaPhonic.com>
Date: Mon, 11 Nov 2019 16:40:05 -0800
Subject: [PATCH 3/3] Added unit test to test that new cloning feature works as
 intended

---
 openssl/src/sha.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/openssl/src/sha.rs b/openssl/src/sha.rs
index a33a0f6c..7f6c4067 100644
--- a/openssl/src/sha.rs
+++ b/openssl/src/sha.rs
@@ -313,6 +313,20 @@ mod test {
         assert_eq!(hex::encode(hasher.finish()), expected);
     }
 
+    #[test]
+    fn cloning_allows_incremental_hashing() {
+        let expected = "a9993e364706816aba3e25717850c26c9cd0d89d";
+
+        let mut hasher = Sha1::new();
+        hasher.update(b"a");
+
+        let mut incr_hasher = hasher.clone();
+        incr_hasher.update(b"bc");
+
+        assert_eq!(hex::encode(incr_hasher.finish()), expected);
+        assert_ne!(hex::encode(hasher.finish()), expected);
+    }
+
     #[test]
     fn standalone_224() {
         let data = b"abc";