Remove padding using new encryption API

benches/key.rs

@@ -6,7 +6,9 @@ use base64ct::{Base64, Encoding};
 use num_bigint::BigUint;
 use num_traits::{FromPrimitive, Num};
 use rand_chacha::{rand_core::SeedableRng, ChaCha8Rng};
-use rsa::{PaddingScheme, RsaPrivateKey};
+use rsa::signature::RandomizedSigner;
+use rsa::traits::Decryptor;
+use rsa::RsaPrivateKey;
 use sha2::{Digest, Sha256};
 use test::Bencher;
 
@@ -28,30 +30,37 @@ fn get_key() -> RsaPrivateKey {
 #[bench]
 fn bench_rsa_2048_pkcsv1_decrypt(b: &mut Bencher) {
     let priv_key = get_key();
+    let decryption_key = rsa::pkcs1v15::DecryptingKey::new(priv_key);
     let x = Base64::decode_vec(DECRYPT_VAL).unwrap();
 
     b.iter(|| {
-        let res = priv_key
-            .decrypt(PaddingScheme::new_pkcs1v15_encrypt(), &x)
-            .unwrap();
+        let res = decryption_key.decrypt(&x).unwrap();
         test::black_box(res);
     });
 }
 
 #[bench]
 fn bench_rsa_2048_pkcsv1_sign_blinded(b: &mut Bencher) {
     let priv_key = get_key();
+    let signing_key = rsa::pkcs1v15::SigningKey::<Sha256>::new_with_prefix(priv_key);
     let digest = Sha256::digest(b"testing").to_vec();
     let mut rng = ChaCha8Rng::from_seed([42; 32]);
 
     b.iter(|| {
-        let res = priv_key
-            .sign_blinded(
-                &mut rng,
-                PaddingScheme::new_pkcs1v15_sign::<Sha256>(),
-                &digest,
-            )
-            .unwrap();
+        let res = signing_key.sign_with_rng(&mut rng, &digest);
+        test::black_box(res);
+    });
+}
+
+#[bench]
+fn bench_rsa_2048_pss_sign_blinded(b: &mut Bencher) {
+    let priv_key = get_key();
+    let signing_key = rsa::pss::SigningKey::<Sha256>::new(priv_key);
+    let digest = Sha256::digest(b"testing").to_vec();
+    let mut rng = ChaCha8Rng::from_seed([42; 32]);
+
+    b.iter(|| {
+        let res = signing_key.sign_with_rng(&mut rng, &digest);
         test::black_box(res);
     });
 }

src/algorithms.rs

@@ -1,6 +1,6 @@
 //! Useful algorithms related to RSA.
 
-use digest::{Digest, DynDigest, FixedOutputReset};
+use digest::{Digest, FixedOutputReset};
 use num_bigint::traits::ModInverse;
 use num_bigint::{BigUint, RandPrime};
 #[allow(unused_imports)]
@@ -135,37 +135,6 @@ pub fn generate_multi_prime_key_with_exp<R: CryptoRngCore + ?Sized>(
     RsaPrivateKey::from_components(n_final, exp.clone(), d_final, primes)
 }
 
-/// Mask generation function.
-///
-/// Panics if out is larger than 2**32. This is in accordance with RFC 8017 - PKCS #1 B.2.1
-pub fn mgf1_xor(out: &mut [u8], digest: &mut dyn DynDigest, seed: &[u8]) {
-    let mut counter = [0u8; 4];
-    let mut i = 0;
-
-    const MAX_LEN: u64 = core::u32::MAX as u64 + 1;
-    assert!(out.len() as u64 <= MAX_LEN);
-
-    while i < out.len() {
-        let mut digest_input = vec![0u8; seed.len() + 4];
-        digest_input[0..seed.len()].copy_from_slice(seed);
-        digest_input[seed.len()..].copy_from_slice(&counter);
-
-        digest.update(digest_input.as_slice());
-        let digest_output = &*digest.finalize_reset();
-        let mut j = 0;
-        loop {
-            if j >= digest_output.len() || i >= out.len() {
-                break;
-            }
-
-            out[i] ^= digest_output[j];
-            j += 1;
-            i += 1;
-        }
-        inc_counter(&mut counter);
-    }
-}
-
 /// Mask generation function.
 ///
 /// Panics if out is larger than 2**32. This is in accordance with RFC 8017 - PKCS #1 B.2.1