From a6981231c10a8daf5b4df496f221510384981386 Mon Sep 17 00:00:00 2001
From: Igor Katson <igor.katson@gmail.com>
Date: Thu, 1 Jul 2021 17:18:07 +0100
Subject: [PATCH] Add system hasher

---
 Cargo.lock                                  | 37 +++++++++++++++++++++
 crates/librqbit/Cargo.toml                  |  1 +
 crates/librqbit/src/file_ops.rs             |  4 +--
 crates/librqbit/src/peer_binary_protocol.rs |  1 -
 crates/librqbit/src/sha1w.rs                | 28 +++++++++++++++-
 5 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index d7f0a89..534a12b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -148,6 +148,24 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "commoncrypto"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d056a8586ba25a1e4d61cb090900e495952c7886786fc55f909ab2f819b69007"
+dependencies = [
+ "commoncrypto-sys",
+]
+
+[[package]]
+name = "commoncrypto-sys"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fed34f46747aa73dfaa578069fd8279d2818ade2b55f38f22a9401c7f4083e2"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "core-foundation"
 version = "0.9.1"
@@ -173,6 +191,18 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crypto-hash"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a77162240fd97248d19a564a565eb563a3f592b386e4136fb300909e67dddca"
+dependencies = [
+ "commoncrypto",
+ "hex",
+ "openssl",
+ "winapi",
+]
+
 [[package]]
 name = "digest"
 version = "0.9.0"
@@ -444,6 +474,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "hex"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
+
 [[package]]
 name = "http"
 version = "0.2.4"
@@ -604,6 +640,7 @@ dependencies = [
  "bincode",
  "bitvec",
  "byteorder",
+ "crypto-hash",
  "futures",
  "log",
  "openssl",
diff --git a/crates/librqbit/Cargo.toml b/crates/librqbit/Cargo.toml
index 7beaf75..55c5040 100644
--- a/crates/librqbit/Cargo.toml
+++ b/crates/librqbit/Cargo.toml
@@ -22,6 +22,7 @@ size_format = "1"
 rand = "0.8"
 openssl = "0.10"
 warp = "0.3"
+crypto-hash = "0.3"
 
 uuid = {version = "0.8", features = ["v4"]}
 futures = "0.3"
diff --git a/crates/librqbit/src/file_ops.rs b/crates/librqbit/src/file_ops.rs
index c75e77c..7c52879 100644
--- a/crates/librqbit/src/file_ops.rs
+++ b/crates/librqbit/src/file_ops.rs
@@ -121,7 +121,7 @@ impl<'a> FileOps<'a> {
         let mut read_buffer = vec![0u8; 65536];
 
         for piece_info in self.lengths.iter_piece_infos() {
-            let mut computed_hash = sha1w::Sha1Openssl::new();
+            let mut computed_hash = sha1w::Sha1System::new();
             let mut piece_remaining = piece_info.len as usize;
             let mut some_files_broken = false;
             let mut at_least_one_file_required = current_file.full_file_required;
@@ -221,7 +221,7 @@ impl<'a> FileOps<'a> {
         piece_index: ValidPieceIndex,
         last_received_chunk: &ChunkInfo,
     ) -> anyhow::Result<bool> {
-        let mut h = sha1w::Sha1Openssl::new();
+        let mut h = sha1w::Sha1System::new();
         let piece_length = self.lengths.piece_length(piece_index);
         let mut absolute_offset = self.lengths.piece_offset(piece_index);
         let mut buf = vec![0u8; std::cmp::min(65536, piece_length as usize)];
diff --git a/crates/librqbit/src/peer_binary_protocol.rs b/crates/librqbit/src/peer_binary_protocol.rs
index 9e844ce..d873033 100644
--- a/crates/librqbit/src/peer_binary_protocol.rs
+++ b/crates/librqbit/src/peer_binary_protocol.rs
@@ -266,7 +266,6 @@ where
                 PREAMBLE_LEN
             }
             Message::Piece(p) => {
-                // below code is wrong, need to serialize len_prefix
                 let block_len = p.block.as_ref().len();
                 let payload_len = 8 + block_len;
                 let msg_len = PREAMBLE_LEN + payload_len;
diff --git a/crates/librqbit/src/sha1w.rs b/crates/librqbit/src/sha1w.rs
index c26a17d..976a1e3 100644
--- a/crates/librqbit/src/sha1w.rs
+++ b/crates/librqbit/src/sha1w.rs
@@ -1,8 +1,10 @@
+use std::io::Write;
+
 // Wrapper for sha1 libraries.
 // Sha1 computation is the majority of CPU usage of this library.
 // openssl seems 2-3x faster, so using it for now, but
 // leaving the pure-rust impl here too. Maybe someday make them
-// runtime swappable.
+// runtime swappable or enabled with a feature.
 
 pub trait ISha1 {
     fn new() -> Self;
@@ -47,3 +49,27 @@ impl ISha1 for Sha1Openssl {
         self.inner.finish()
     }
 }
+
+pub struct Sha1System {
+    inner: crypto_hash::Hasher,
+}
+
+impl ISha1 for Sha1System {
+    fn new() -> Self {
+        Self {
+            inner: crypto_hash::Hasher::new(crypto_hash::Algorithm::SHA1),
+        }
+    }
+
+    fn update(&mut self, buf: &[u8]) {
+        self.inner.write_all(buf).unwrap();
+    }
+
+    fn finish(mut self) -> [u8; 20] {
+        let result = self.inner.finish();
+        assert_eq!(result.len(), 20);
+        let mut result_arr = [0u8; 20];
+        result_arr.copy_from_slice(&result);
+        result_arr
+    }
+}