Merge pull request #258 from dadleyy/prefer-iter

perf: avoid `concat` in sha1 checksum impl
rpgp · Dec 9, 2023 · d907163 · d907163
2 parents 63f55a7 + 036943b
commit d907163
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Showing 4 changed files with 13 additions and 4 deletions.
diff --git a/src/crypto/checksum.rs b/src/crypto/checksum.rs
@@ -82,6 +82,14 @@ impl Hasher for SimpleChecksum {
 
 /// SHA1 checksum, first 20 octets.
 #[inline]
-pub fn calculate_sha1(data: &[u8]) -> Vec<u8> {
-    Sha1::digest(data)[..20].to_vec()
+pub fn calculate_sha1<I, T>(data: I) -> Vec<u8>
+where
+    T: AsRef<[u8]>,
+    I: IntoIterator<Item = T>,
+{
+    let mut digest = Sha1::new();
+    for chunk in data {
+        digest.update(chunk.as_ref());
+    }
+    digest.finalize()[..20].to_vec()
 }
diff --git a/src/crypto/sym.rs b/src/crypto/sym.rs
@@ -169,7 +169,7 @@ impl SymmetricKeyAlgorithm {
         let mdc_len = 22;
         let (data, mdc) = res.split_at(res.len() - mdc_len);
 
-        let sha1 = checksum::calculate_sha1(&[prefix, data, &mdc[0..2]].concat());
+        let sha1 = checksum::calculate_sha1([prefix, data, &mdc[0..2]]);
         if mdc[0] != 0xD3 || // Invalid MDC tag
            mdc[1] != 0x14 || // Invalid MDC length
            mdc[2..] != sha1[..]

diff --git a/src/lib.rs b/src/lib.rs
@@ -60,6 +60,7 @@ pub mod ser;
 pub mod types;
 
 // reexports for easier use
+#[allow(unused_imports)]
 pub use self::composed::key::*;
 pub use self::composed::*;
 pub use self::packet::Signature;
diff --git a/src/types/params/plain_secret.rs b/src/types/params/plain_secret.rs
@@ -115,7 +115,7 @@ impl<'a> PlainSecretParamsRef<'a> {
     pub fn checksum_sha1(&self) -> Vec<u8> {
         let mut buf = Vec::new();
         self.to_writer_raw(&mut buf).expect("known write target");
-        checksum::calculate_sha1(&buf)
+        checksum::calculate_sha1([&buf])
     }
 
     pub fn as_repr(&self, public_params: &PublicParams) -> Result<SecretKeyRepr> {