Make rust-tls work (through ring)

crates/sha1w/src/lib.rs

@@ -5,35 +5,75 @@
 // openssl is 2-3x faster than rust's sha1.
 // system library is the best choice probably (it's the default anyway).
 
-pub type Sha1 = Sha1System;
-
 pub trait ISha1 {
     fn new() -> Self;
     fn update(&mut self, buf: &[u8]);
     fn finish(self) -> [u8; 20];
 }
 
-pub struct Sha1System {
-    inner: crypto_hash::Hasher,
-}
+#[cfg(feature = "sha1-crypto-hash")]
+mod crypto_hash_impl {
+    use super::ISha1;
 
-impl ISha1 for Sha1System {
-    fn new() -> Self {
-        Self {
-            inner: crypto_hash::Hasher::new(crypto_hash::Algorithm::SHA1),
+    pub struct Sha1CryptoHash {
+        inner: crypto_hash::Hasher,
+    }
+
+    impl ISha1 for Sha1CryptoHash {
+        fn new() -> Self {
+            Self {
+                inner: crypto_hash::Hasher::new(crypto_hash::Algorithm::SHA1),
+            }
+        }
+
+        fn update(&mut self, buf: &[u8]) {
+            use std::io::Write;
+            self.inner.write_all(buf).unwrap();
+        }
+
+        fn finish(mut self) -> [u8; 20] {
+            let result = self.inner.finish();
+            debug_assert_eq!(result.len(), 20);
+            let mut result_arr = [0u8; 20];
+            result_arr.copy_from_slice(&result);
+            result_arr
         }
     }
+}
 
-    fn update(&mut self, buf: &[u8]) {
-        use std::io::Write;
-        self.inner.write_all(buf).unwrap();
+#[cfg(feature = "sha1-ring")]
+mod ring_impl {
+    use super::ISha1;
+
+    use ring::digest::{Context, SHA1_FOR_LEGACY_USE_ONLY as SHA1};
+
+    pub struct Sha1Ring {
+        ctx: Context,
     }
 
-    fn finish(mut self) -> [u8; 20] {
-        let result = self.inner.finish();
-        debug_assert_eq!(result.len(), 20);
-        let mut result_arr = [0u8; 20];
-        result_arr.copy_from_slice(&result);
-        result_arr
+    impl ISha1 for Sha1Ring {
+        fn new() -> Self {
+            Self {
+                ctx: Context::new(&SHA1),
+            }
+        }
+
+        fn update(&mut self, buf: &[u8]) {
+            self.ctx.update(buf);
+        }
+
+        fn finish(self) -> [u8; 20] {
+            let result = self.ctx.finish();
+            debug_assert_eq!(result.as_ref().len(), 20);
+            let mut result_arr = [0u8; 20];
+            result_arr.copy_from_slice(result.as_ref());
+            result_arr
+        }
     }
 }
+
+#[cfg(feature = "sha1-crypto-hash")]
+pub type Sha1 = crypto_hash_impl::Sha1CryptoHash;
+
+#[cfg(feature = "sha1-ring")]
+pub type Sha1 = ring_impl::Sha1Ring;