feat: switch to CryptoRngCore

Follow the signature v2 change and Switch the rest of the code ot use
CryptoRngCore instead of CryptoRng+RngCore combo.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

src/algorithms.rs

@@ -6,7 +6,7 @@ use num_bigint::{BigUint, RandPrime};
 #[allow(unused_imports)]
 use num_traits::Float;
 use num_traits::{FromPrimitive, One, Zero};
-use rand_core::{CryptoRng, RngCore};
+use rand_core::CryptoRngCore;
 
 use crate::errors::{Error, Result};
 use crate::key::RsaPrivateKey;
@@ -29,7 +29,7 @@ const EXP: u64 = 65537;
 ///
 /// [1]: https://patents.google.com/patent/US4405829A/en
 /// [2]: https://cacr.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
-pub fn generate_multi_prime_key<R: RngCore + CryptoRng>(
+pub fn generate_multi_prime_key<R: CryptoRngCore>(
     rng: &mut R,
     nprimes: usize,
     bit_size: usize,
@@ -49,7 +49,7 @@ pub fn generate_multi_prime_key<R: RngCore + CryptoRng>(
 ///
 /// [1]: https://patents.google.com/patent/US4405829A/en
 /// [2]: http://www.cacr.math.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
-pub fn generate_multi_prime_key_with_exp<R: RngCore + CryptoRng>(
+pub fn generate_multi_prime_key_with_exp<R: CryptoRngCore>(
     rng: &mut R,
     nprimes: usize,
     bit_size: usize,

src/internals.rs

@@ -3,7 +3,7 @@ use alloc::vec;
 use alloc::vec::Vec;
 use num_bigint::{BigInt, BigUint, IntoBigInt, IntoBigUint, ModInverse, RandBigInt, ToBigInt};
 use num_traits::{One, Signed, Zero};
-use rand_core::{CryptoRng, RngCore};
+use rand_core::CryptoRngCore;
 use zeroize::Zeroize;
 
 use crate::errors::{Error, Result};
@@ -18,7 +18,7 @@ pub fn encrypt<K: PublicKeyParts>(key: &K, m: &BigUint) -> BigUint {
 /// Performs raw RSA decryption with no padding, resulting in a plaintext `BigUint`.
 /// Peforms RSA blinding if an `Rng` is passed.
 #[inline]
-pub fn decrypt<R: RngCore + CryptoRng>(
+pub fn decrypt<R: CryptoRngCore>(
     mut rng: Option<&mut R>,
     priv_key: &RsaPrivateKey,
     c: &BigUint,
@@ -108,7 +108,7 @@ pub fn decrypt<R: RngCore + CryptoRng>(
 /// Peforms RSA blinding if an `Rng` is passed.
 /// This will also check for errors in the CRT computation.
 #[inline]
-pub fn decrypt_and_check<R: RngCore + CryptoRng>(
+pub fn decrypt_and_check<R: CryptoRngCore>(
     rng: Option<&mut R>,
     priv_key: &RsaPrivateKey,
     c: &BigUint,
@@ -127,7 +127,7 @@ pub fn decrypt_and_check<R: RngCore + CryptoRng>(
 }
 
 /// Returns the blinded c, along with the unblinding factor.
-pub fn blind<R: RngCore + CryptoRng, K: PublicKeyParts>(
+pub fn blind<R: CryptoRngCore, K: PublicKeyParts>(
     rng: &mut R,
     key: &K,
     c: &BigUint,

src/key.rs

@@ -4,7 +4,7 @@ use num_bigint::traits::ModInverse;
 use num_bigint::Sign::Plus;
 use num_bigint::{BigInt, BigUint};
 use num_traits::{One, ToPrimitive};
-use rand_core::{CryptoRng, RngCore};
+use rand_core::CryptoRngCore;
 #[cfg(feature = "serde")]
 use serde_crate::{Deserialize, Serialize};
 use zeroize::Zeroize;
@@ -173,7 +173,7 @@ impl From<&RsaPrivateKey> for RsaPublicKey {
 /// Generic trait for operations on a public key.
 pub trait PublicKey: EncryptionPrimitive + PublicKeyParts {
     /// Encrypt the given message.
-    fn encrypt<R: RngCore + CryptoRng>(
+    fn encrypt<R: CryptoRngCore>(
         &self,
         rng: &mut R,
         padding: PaddingScheme,
@@ -198,7 +198,7 @@ impl PublicKeyParts for RsaPublicKey {
 }
 
 impl PublicKey for RsaPublicKey {
-    fn encrypt<R: RngCore + CryptoRng>(
+    fn encrypt<R: CryptoRngCore>(
         &self,
         rng: &mut R,
         padding: PaddingScheme,
@@ -281,15 +281,15 @@ impl PrivateKey for RsaPrivateKey {}
 
 impl RsaPrivateKey {
     /// Generate a new Rsa key pair of the given bit size using the passed in `rng`.
-    pub fn new<R: RngCore + CryptoRng>(rng: &mut R, bit_size: usize) -> Result<RsaPrivateKey> {
+    pub fn new<R: CryptoRngCore>(rng: &mut R, bit_size: usize) -> Result<RsaPrivateKey> {
         generate_multi_prime_key(rng, 2, bit_size)
     }
 
     /// Generate a new RSA key pair of the given bit size and the public exponent
     /// using the passed in `rng`.
     ///
     /// Unless you have specific needs, you should use `RsaPrivateKey::new` instead.
-    pub fn new_with_exp<R: RngCore + CryptoRng>(
+    pub fn new_with_exp<R: CryptoRngCore>(
         rng: &mut R,
         bit_size: usize,
         exp: &BigUint,
@@ -458,7 +458,7 @@ impl RsaPrivateKey {
     /// Decrypt the given message.
     ///
     /// Uses `rng` to blind the decryption process.
-    pub fn decrypt_blinded<R: RngCore + CryptoRng>(
+    pub fn decrypt_blinded<R: CryptoRngCore>(
         &self,
         rng: &mut R,
         padding: PaddingScheme,
@@ -501,7 +501,7 @@ impl RsaPrivateKey {
     /// Sign the given digest using the provided rng
     ///
     /// Use `rng` for signature process.
-    pub fn sign_with_rng<R: RngCore + CryptoRng>(
+    pub fn sign_with_rng<R: CryptoRngCore>(
         &self,
         rng: &mut R,
         padding: PaddingScheme,
@@ -519,7 +519,7 @@ impl RsaPrivateKey {
     /// Sign the given digest.
     ///
     /// Use `rng` for blinding.
-    pub fn sign_blinded<R: RngCore + CryptoRng>(
+    pub fn sign_blinded<R: CryptoRngCore>(
         &self,
         rng: &mut R,
         padding: PaddingScheme,

src/oaep.rs

@@ -1,7 +1,7 @@
 use alloc::string::String;
 use alloc::vec;
 use alloc::vec::Vec;
-use rand_core::{CryptoRng, RngCore};
+use rand_core::CryptoRngCore;
 
 use digest::DynDigest;
 use subtle::{Choice, ConditionallySelectable, ConstantTimeEq, CtOption};
@@ -23,7 +23,7 @@ const MAX_LABEL_LEN: u64 = 2_305_843_009_213_693_951;
 ///
 /// [PKCS#1 OAEP]: https://datatracker.ietf.org/doc/html/rfc8017#section-7.1
 #[inline]
-pub fn encrypt<R: RngCore + CryptoRng, K: PublicKey>(
+pub fn encrypt<R: CryptoRngCore, K: PublicKey>(
     rng: &mut R,
     pub_key: &K,
     msg: &[u8],
@@ -80,7 +80,7 @@ pub fn encrypt<R: RngCore + CryptoRng, K: PublicKey>(
 ///
 /// [PKCS#1 OAEP]: https://datatracker.ietf.org/doc/html/rfc8017#section-7.1
 #[inline]
-pub fn decrypt<R: RngCore + CryptoRng, SK: PrivateKey>(
+pub fn decrypt<R: CryptoRngCore, SK: PrivateKey>(
     rng: Option<&mut R>,
     priv_key: &SK,
     ciphertext: &[u8],
@@ -104,7 +104,7 @@ pub fn decrypt<R: RngCore + CryptoRng, SK: PrivateKey>(
 /// `rng` is given. It returns one or zero in valid that indicates whether the
 /// plaintext was correctly structured.
 #[inline]
-fn decrypt_inner<R: RngCore + CryptoRng, SK: PrivateKey>(
+fn decrypt_inner<R: CryptoRngCore, SK: PrivateKey>(
     rng: Option<&mut R>,
     priv_key: &SK,
     ciphertext: &[u8],

src/pkcs1v15.rs

@@ -8,7 +8,7 @@ use core::fmt::{Debug, Display, Formatter, LowerHex, UpperHex};
 use core::marker::PhantomData;
 use digest::Digest;
 use pkcs8::{AssociatedOid, Document, EncodePrivateKey, EncodePublicKey, SecretDocument};
-use rand_core::{CryptoRng, CryptoRngCore, RngCore};
+use rand_core::CryptoRngCore;
 use signature::{
     hazmat::{PrehashSigner, PrehashVerifier},
     DigestSigner, DigestVerifier, Keypair, RandomizedDigestSigner, RandomizedSigner,
@@ -96,7 +96,7 @@ impl Display for Signature {
 /// scheme from PKCS#1 v1.5.  The message must be no longer than the
 /// length of the public modulus minus 11 bytes.
 #[inline]
-pub(crate) fn encrypt<R: RngCore + CryptoRng, PK: PublicKey>(
+pub(crate) fn encrypt<R: CryptoRngCore, PK: PublicKey>(
     rng: &mut R,
     pub_key: &PK,
     msg: &[u8],
@@ -128,7 +128,7 @@ pub(crate) fn encrypt<R: RngCore + CryptoRng, PK: PublicKey>(
 /// forge signatures as if they had the private key. See
 /// `decrypt_session_key` for a way of solving this problem.
 #[inline]
-pub(crate) fn decrypt<R: RngCore + CryptoRng, SK: PrivateKey>(
+pub(crate) fn decrypt<R: CryptoRngCore, SK: PrivateKey>(
     rng: Option<&mut R>,
     priv_key: &SK,
     ciphertext: &[u8],
@@ -157,7 +157,7 @@ pub(crate) fn decrypt<R: RngCore + CryptoRng, SK: PrivateKey>(
 /// messages to signatures and identify the signed messages. As ever,
 /// signatures provide authenticity, not confidentiality.
 #[inline]
-pub(crate) fn sign<R: RngCore + CryptoRng, SK: PrivateKey>(
+pub(crate) fn sign<R: CryptoRngCore, SK: PrivateKey>(
     rng: Option<&mut R>,
     priv_key: &SK,
     prefix: &[u8],
@@ -245,7 +245,7 @@ where
 /// in order to maintain constant memory access patterns. If the plaintext was
 /// valid then index contains the index of the original message in em.
 #[inline]
-fn decrypt_inner<R: RngCore + CryptoRng, SK: PrivateKey>(
+fn decrypt_inner<R: CryptoRngCore, SK: PrivateKey>(
     rng: Option<&mut R>,
     priv_key: &SK,
     ciphertext: &[u8],
@@ -290,7 +290,7 @@ fn decrypt_inner<R: RngCore + CryptoRng, SK: PrivateKey>(
 /// Fills the provided slice with random values, which are guaranteed
 /// to not be zero.
 #[inline]
-fn non_zero_random_bytes<R: RngCore + CryptoRng>(rng: &mut R, data: &mut [u8]) {
+fn non_zero_random_bytes<R: CryptoRngCore>(rng: &mut R, data: &mut [u8]) {
     rng.fill_bytes(data);
 
     for el in data {
@@ -595,7 +595,10 @@ mod tests {
     use num_bigint::BigUint;
     use num_traits::FromPrimitive;
     use num_traits::Num;
-    use rand_chacha::{rand_core::SeedableRng, ChaCha8Rng};
+    use rand_chacha::{
+        rand_core::{RngCore, SeedableRng},
+        ChaCha8Rng,
+    };
     use sha1::{Digest, Sha1};
     use sha2::Sha256;
     use sha3::Sha3_256;

src/pss.rs

@@ -12,7 +12,7 @@ use core::fmt::{Debug, Display, Formatter, LowerHex, UpperHex};
 use core::marker::PhantomData;
 use digest::{Digest, DynDigest, FixedOutputReset};
 use pkcs8::{Document, EncodePrivateKey, EncodePublicKey, SecretDocument};
-use rand_core::{CryptoRng, CryptoRngCore, RngCore};
+use rand_core::CryptoRngCore;
 use signature::{
     hazmat::{PrehashVerifier, RandomizedPrehashSigner},
     DigestVerifier, Keypair, RandomizedDigestSigner, RandomizedSigner, SignatureEncoding, Verifier,
@@ -132,8 +132,7 @@ where
 /// Note that hashed must be the result of hashing the input message using the
 /// given hash function. The opts argument may be nil, in which case sensible
 /// defaults are used.
-// TODO: bind T with the CryptoRng trait
-pub(crate) fn sign<T: RngCore + CryptoRng, SK: PrivateKey>(
+pub(crate) fn sign<T: CryptoRngCore, SK: PrivateKey>(
     rng: &mut T,
     blind: bool,
     priv_key: &SK,
@@ -146,7 +145,7 @@ pub(crate) fn sign<T: RngCore + CryptoRng, SK: PrivateKey>(
     sign_pss_with_salt(blind.then(|| rng), priv_key, hashed, &salt, digest)
 }
 
-pub(crate) fn sign_digest<T: RngCore + CryptoRng, SK: PrivateKey, D: Digest + FixedOutputReset>(
+pub(crate) fn sign_digest<T: CryptoRngCore, SK: PrivateKey, D: Digest + FixedOutputReset>(
     rng: &mut T,
     blind: bool,
     priv_key: &SK,
@@ -158,7 +157,7 @@ pub(crate) fn sign_digest<T: RngCore + CryptoRng, SK: PrivateKey, D: Digest + Fi
     sign_pss_with_salt_digest::<_, _, D>(blind.then(|| rng), priv_key, hashed, &salt)
 }
 
-fn generate_salt<T: RngCore + ?Sized, SK: PrivateKey>(
+fn generate_salt<T: CryptoRngCore + ?Sized, SK: PrivateKey>(
     rng: &mut T,
     priv_key: &SK,
     salt_len: Option<usize>,
@@ -177,7 +176,7 @@ fn generate_salt<T: RngCore + ?Sized, SK: PrivateKey>(
 /// Note that hashed must be the result of hashing the input message using the
 /// given hash function. salt is a random sequence of bytes whose length will be
 /// later used to verify the signature.
-fn sign_pss_with_salt<T: CryptoRng + RngCore, SK: PrivateKey>(
+fn sign_pss_with_salt<T: CryptoRngCore, SK: PrivateKey>(
     blind_rng: Option<&mut T>,
     priv_key: &SK,
     hashed: &[u8],
@@ -190,11 +189,7 @@ fn sign_pss_with_salt<T: CryptoRng + RngCore, SK: PrivateKey>(
     priv_key.raw_decryption_primitive(blind_rng, &em, priv_key.size())
 }
 
-fn sign_pss_with_salt_digest<
-    T: CryptoRng + RngCore,
-    SK: PrivateKey,
-    D: Digest + FixedOutputReset,
->(
+fn sign_pss_with_salt_digest<T: CryptoRngCore, SK: PrivateKey, D: Digest + FixedOutputReset>(
     blind_rng: Option<&mut T>,
     priv_key: &SK,
     hashed: &[u8],

src/raw.rs

@@ -1,6 +1,6 @@
 use alloc::vec::Vec;
 use num_bigint::BigUint;
-use rand_core::{CryptoRng, RngCore};
+use rand_core::CryptoRngCore;
 use zeroize::Zeroize;
 
 use crate::errors::{Error, Result};
@@ -14,7 +14,7 @@ pub trait EncryptionPrimitive {
 
 pub trait DecryptionPrimitive {
     /// Do NOT use directly! Only for implementors.
-    fn raw_decryption_primitive<R: RngCore + CryptoRng>(
+    fn raw_decryption_primitive<R: CryptoRngCore>(
         &self,
         rng: Option<&mut R>,
         ciphertext: &[u8],
@@ -43,7 +43,7 @@ impl EncryptionPrimitive for RsaPublicKey {
 }
 
 impl DecryptionPrimitive for RsaPrivateKey {
-    fn raw_decryption_primitive<R: RngCore + CryptoRng>(
+    fn raw_decryption_primitive<R: CryptoRngCore>(
         &self,
         rng: Option<&mut R>,
         ciphertext: &[u8],