wrap: use RsaPrivateKey::from_p_q

See RustCrypto/RSA#386

Cargo.toml

@@ -25,13 +25,12 @@ ccm = { version = "0.5", features = ["std"] }
 ecdsa = { version = "0.16", default-features = false }
 ed25519 = "2"
 log = "0.4"
-num-bigint = { version = "0.8.2", features = ["i128", "prime", "zeroize"], default-features = false, package = "num-bigint-dig" }
 num-traits = "0.2"
 p256 = { version = "0.13", default-features = false, features = ["ecdsa"] }
 p384 = { version = "0.13", default-features = false, features = ["ecdsa"] }
 serde = { version = "1", features = ["serde_derive"] }
 rand_core = { version = "0.6", features = ["std"] }
-rsa = "0.9"
+rsa = "0.9.5"
 signature = { version = "2", features = ["derive"] }
 subtle = "2"
 thiserror = "1"

src/wrap/message.rs

@@ -17,8 +17,7 @@ use ecdsa::{
     },
     PrimeCurve,
 };
-use num_bigint::traits::ModInverse;
-use num_traits::{cast::FromPrimitive, identities::One};
+use num_traits::cast::FromPrimitive;
 use rsa::{BigUint, RsaPrivateKey};
 use serde::{Deserialize, Serialize};
 
@@ -141,19 +140,15 @@ impl Plaintext {
 
         let p = BigUint::from_bytes_be(reader.read(component_size)?);
         let q = BigUint::from_bytes_be(reader.read(component_size)?);
-        let dp = BigUint::from_bytes_be(reader.read(component_size)?);
-        let dq = BigUint::from_bytes_be(reader.read(component_size)?);
+        let _dp = BigUint::from_bytes_be(reader.read(component_size)?);
+        let _dq = BigUint::from_bytes_be(reader.read(component_size)?);
         let _qinv = BigUint::from_bytes_be(reader.read(component_size)?);
-        let n = BigUint::from_bytes_be(reader.read(modulus_size)?);
+        let _n = BigUint::from_bytes_be(reader.read(modulus_size)?);
         const EXP: u64 = 65537;
         let e = BigUint::from_u64(EXP).expect("invalid static exponent");
 
-        let d = e
-            .clone()
-            .mod_inverse((dp - BigUint::one()) * (dq - BigUint::one()))?
-            .to_biguint()?;
+        let private_key = RsaPrivateKey::from_p_q(p, q, e).ok()?;
 
-        let private_key = RsaPrivateKey::from_components(n, e, d, vec![p, q]).ok()?;
         Some(private_key)
     }
 }