dsa: Implement signature traits directly on the structures

Author: aumetra

dsa/Cargo.toml

@@ -14,14 +14,13 @@ num-bigint = { package = "num-bigint-dig", version = "0.8.1", default-features =
 num-traits = { version = "0.2.15", default-features = false }
 opaque-debug = "0.3.0"
 paste = "1.0.7"
-pkcs8 = { version = "0.9.0", default-features = false, features = ["alloc"] }
+pkcs8 = { version = "0.9.0", default-features = false }
 rand = { version = "0.8.5", default-features = false }
-signature = { version = "1.5.0", optional = true }
+signature = { version = ">= 1.5.0, < 1.6.0", default-features = false, features = ["digest-preview", "rand-preview"] }
 zeroize = { version = "1.5.5", default-features = false }
 
 [features]
-default = ["signature-compat"]
-signature-compat = ["signature", "pkcs8/std", "rand/std", "rand/std_rng"]
+default = []
 
 [dev-dependencies]
 pkcs8 = { version = "0.9.0", default-features = false, features = ["pem"] }

dsa/examples/export.rs

@@ -8,18 +8,14 @@ fn main() {
     let private_key = PrivateKey::generate(&mut rng, components);
     let public_key = private_key.public_key();
 
+    let private_key_bytes = private_key.to_pkcs8_pem(LineEnding::LF).unwrap();
+    let public_key_bytes = public_key.to_public_key_pem(LineEnding::LF).unwrap();
+
     let mut file = File::create("public.pem").unwrap();
-    file.write_all(
-        public_key
-            .to_public_key_pem(LineEnding::LF)
-            .unwrap()
-            .as_bytes(),
-    )
-    .unwrap();
+    file.write_all(public_key_bytes.as_bytes()).unwrap();
     file.flush().unwrap();
 
     let mut file = File::create("private.pem").unwrap();
-    file.write_all(private_key.to_pkcs8_pem(LineEnding::LF).unwrap().as_bytes())
-        .unwrap();
+    file.write_all(private_key_bytes.as_bytes()).unwrap();
     file.flush().unwrap();
 }

dsa/examples/sign.rs

@@ -1,34 +1,31 @@
+use digest::Digest;
 use dsa::{consts::DSA_2048_256, Components, PrivateKey};
-use pkcs8::{der::Encode, EncodePrivateKey, EncodePublicKey, LineEnding};
+use pkcs8::{EncodePrivateKey, EncodePublicKey, LineEnding};
 use sha1::Sha1;
+use signature::{RandomizedDigestSigner, Signature};
 use std::{fs::File, io::Write};
 
 fn main() {
     let mut rng = rand::thread_rng();
     let components = Components::generate(&mut rng, DSA_2048_256);
     let private_key = PrivateKey::generate(&mut rng, components);
     let public_key = private_key.public_key();
+
     let signature = private_key
-        .sign::<_, Sha1>(&mut rng, b"hello world")
-        .unwrap();
+        .sign_digest_with_rng(rand::thread_rng(), Sha1::new().chain_update(b"hello world"));
+
+    let private_key_bytes = private_key.to_pkcs8_pem(LineEnding::LF).unwrap();
+    let public_key_bytes = public_key.to_public_key_pem(LineEnding::LF).unwrap();
 
     let mut file = File::create("public.pem").unwrap();
-    file.write_all(
-        public_key
-            .to_public_key_pem(LineEnding::LF)
-            .unwrap()
-            .as_bytes(),
-    )
-    .unwrap();
+    file.write_all(public_key_bytes.as_bytes()).unwrap();
     file.flush().unwrap();
 
     let mut file = File::create("signature.der").unwrap();
-    file.write_all(signature.to_vec().unwrap().as_ref())
-        .unwrap();
+    file.write_all(signature.as_bytes()).unwrap();
     file.flush().unwrap();
 
     let mut file = File::create("private.pem").unwrap();
-    file.write_all(private_key.to_pkcs8_pem(LineEnding::LF).unwrap().as_bytes())
-        .unwrap();
+    file.write_all(private_key_bytes.as_bytes()).unwrap();
     file.flush().unwrap();
 }

dsa/src/compat.rs

@@ -54,24 +54,24 @@
 //! ```
 //!
 
-#![cfg_attr(not(feature = "signature-compat"), no_std)]
+#![no_std]
 #![forbid(missing_docs, unsafe_code)]
 #![deny(rust_2018_idioms)]
 
+extern crate alloc;
+
 /// DSA object identifier as defined by RFC-3279, section 2.3.2
 const DSA_OID: ObjectIdentifier = ObjectIdentifier::new_unwrap("1.2.840.10040.4.1");
 
 pub use self::components::Components;
 pub use self::privatekey::PrivateKey;
 pub use self::publickey::PublicKey;
-pub use self::signature::Signature;
+pub use self::sig::Signature;
 
 // Re-export the types needed for de-/serialising keys to DER and PEM
 pub use pkcs8;
+pub use signature;
 
-#[cfg(feature = "signature-compat")]
-#[cfg_attr(doc_cfg, doc(cfg(feature = "signature-compat")))]
-pub mod compat;
 pub mod consts;
 
 use num_bigint::BigUint;
@@ -81,7 +81,7 @@ mod components;
 mod generate;
 mod privatekey;
 mod publickey;
-mod signature;
+mod sig;
 
 /// Returns a `BigUint` with the value 2
 #[inline]