openpgp: Use ahash instead of xxhash.neal/partial-body-hash

  - According to the `ahash` `README`, it performs better than
    `xxhash`.

  - `ahash` is also used by some of our dependencies, `xxhash` isn't.

  - Fixes #1074.

4 files changed, 50 insertions, 22 deletions

diff --git a/Cargo.lock b/Cargo.lock
index f5c4b61d..b21c388d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -54,6 +54,19 @@ dependencies = [
 ]
 
 [[package]]
+name = "ahash"
+version = "0.8.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77c3a9648d43b9cd48db467b3f87fdd6e146bcc88ab0180006cef2179fe11d01"
+dependencies = [
+ "cfg-if",
+ "getrandom",
+ "once_cell",
+ "version_check",
+ "zerocopy",
+]
+
+[[package]]
 name = "aho-corasick"
 version = "1.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2601,6 +2614,7 @@ version = "1.17.0"
 dependencies = [
  "aes",
  "aes-gcm",
+ "ahash",
  "anyhow",
  "base64",
  "block-padding",
@@ -2655,7 +2669,6 @@ dependencies = [
  "win-crypto-ng",
  "winapi",
  "x25519-dalek",
- "xxhash-rust",
 ]
 
 [[package]]
@@ -3378,18 +3391,32 @@ dependencies = [
 ]
 
 [[package]]
-name = "xxhash-rust"
-version = "0.8.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9828b178da53440fa9c766a3d2f73f7cf5d0ac1fe3980c1e5018d899fd19e07b"
-
-[[package]]
 name = "z-base-32"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "80a0d98613370af88e15bd2047702d7c78c8c6aba44403eb227c8ad706871f92"
 
 [[package]]
+name = "zerocopy"
+version = "0.7.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "74d4d3961e53fa4c9a25a8637fc2bfaf2595b3d3ae34875568a5cf64787716be"
+dependencies = [
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.7.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ce1b18ccd8e73a9321186f97e46f9f04b778851177567b1975109d26a08d2a6"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
 name = "zeroize"
 version = "1.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/openpgp/Cargo.toml b/openpgp/Cargo.toml
index de75a852..847b5733 100644
--- a/openpgp/Cargo.toml
+++ b/openpgp/Cargo.toml
@@ -44,7 +44,7 @@ regex = "1"
 regex-syntax = "0.8"
 sha1collisiondetection = { version = "0.3.1", default-features = false, features = ["std"] }
 thiserror = "1.0.2"
-xxhash-rust = { version = "0.8", features = ["xxh3"] }
+ahash = { version = "0.8", features = ["std"] }
 
 # At least 0.10.55 is needed due `no-ocb` check:
 # https://github.com/sfackler/rust-openssl/blob/master/openssl/CHANGELOG.md
diff --git a/openpgp/src/packet/container.rs b/openpgp/src/packet/container.rs
index fd8c0f2f..fb713979 100644
--- a/openpgp/src/packet/container.rs
+++ b/openpgp/src/packet/container.rs
@@ -8,7 +8,7 @@ use std::hash::{Hash, Hasher};
 use std::slice;
 use std::vec;
 
-use xxhash_rust::xxh3::Xxh3;
+use ahash::AHasher;
 
 use crate::{
     Packet,
@@ -287,8 +287,8 @@ impl Container {
         use Body::*;
         let mut h = Self::make_body_hash();
         match &body {
-            Unprocessed(bytes) => h.update(bytes),
-            Processed(bytes) => h.update(bytes),
+            Unprocessed(bytes) => h.write(bytes),
+            Processed(bytes) => h.write(bytes),
             Structured(_) => (),
         }
         self.set_body_hash(h);
@@ -299,7 +299,7 @@ impl Container {
     fn empty_body_digest() -> u64 {
         lazy_static::lazy_static!{
             static ref DIGEST: u64 = {
-                Container::make_body_hash().digest()
+                Container::make_body_hash().finish()
             };
         }
 
@@ -308,14 +308,14 @@ impl Container {
 
     /// Creates a hash context for hashing the body.
     pub(crate) // For parse.rs
-    fn make_body_hash() -> Box<Xxh3> {
-        Box::new(Xxh3::new())
+    fn make_body_hash() -> Box<AHasher> {
+        Box::new(AHasher::default())
     }
 
     /// Hashes content that has been streamed.
     pub(crate) // For parse.rs
-    fn set_body_hash(&mut self, h: Box<Xxh3>) {
-        self.body_digest = h.digest();
+    fn set_body_hash(&mut self, h: Box<AHasher>) {
+        self.body_digest = h.finish();
     }
 
     pub(crate)
diff --git a/openpgp/src/parse.rs b/openpgp/src/parse.rs
index 4e18acee..510d1cfd 100644
--- a/openpgp/src/parse.rs
+++ b/openpgp/src/parse.rs
@@ -177,13 +177,14 @@ use std::io;
 use std::io::prelude::*;
 use std::convert::TryFrom;
 use std::cmp;
+use std::hash::Hasher;
 use std::str;
 use std::mem;
 use std::fmt;
 use std::path::Path;
 use std::result::Result as StdResult;
 
-use xxhash_rust::xxh3::Xxh3;
+use ahash::AHasher;
 
 // Re-export buffered_reader.
 //
@@ -3547,7 +3548,7 @@ pub struct PacketParser<'a> {
 
     /// We compute a hashsum over the body to implement comparison on
     /// containers that have been streamed.
-    body_hash: Option<Box<Xxh3>>,
+    body_hash: Option<Box<AHasher>>,
 
     state: PacketParserState,
 }
@@ -5140,7 +5141,7 @@ impl <'a> PacketParser<'a> {
         if !b.is_empty() {
             assert!(self.body_hash.is_some());
             if let Some(h) = self.body_hash.as_mut() {
-                h.update(b);
+                h.write(b);
             }
             self.content_was_read = true;
         }
@@ -5277,7 +5278,7 @@ impl<'a> BufferedReader<Cookie> for PacketParser<'a> {
         if let Some(mut body_hash) = self.body_hash.take() {
             let data = self.data_hard(amount)
                 .expect("It is an error to consume more than data returns");
-            body_hash.update(&data[..amount]);
+            body_hash.write(&data[..amount]);
             self.body_hash = Some(body_hash);
             self.content_was_read |= amount > 0;
         } else {
@@ -5292,7 +5293,7 @@ impl<'a> BufferedReader<Cookie> for PacketParser<'a> {
         if let Some(mut body_hash) = self.body_hash.take() {
             let data = self.data(amount)?;
             amount = cmp::min(data.len(), amount);
-            body_hash.update(&data[..amount]);
+            body_hash.write(&data[..amount]);
             self.body_hash = Some(body_hash);
             self.content_was_read |= amount > 0;
         } else {
@@ -5306,7 +5307,7 @@ impl<'a> BufferedReader<Cookie> for PacketParser<'a> {
         // This is awkward.  Juggle mutable references around.
         if let Some(mut body_hash) = self.body_hash.take() {
             let data = self.data_hard(amount)?;
-            body_hash.update(&data[..amount]);
+            body_hash.write(&data[..amount]);
             self.body_hash = Some(body_hash);
             self.content_was_read |= amount > 0;
         } else {