From b795c22f60a20b1ccd92e212b8697bd02289de61 Mon Sep 17 00:00:00 2001
From: dignifiedquire <me@dignifiedquire.com>
Date: Thu, 30 Nov 2023 22:44:47 +0100
Subject: [PATCH] cache p and q params

---
 src/algorithms/rsa.rs |  8 +++-----
 src/key.rs            | 16 ++++++++++++++++
 src/traits/keys.rs    |  4 ++++
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/src/algorithms/rsa.rs b/src/algorithms/rsa.rs
index b52754b6..b24fc042 100644
--- a/src/algorithms/rsa.rs
+++ b/src/algorithms/rsa.rs
@@ -79,21 +79,19 @@ pub fn rsa_decrypt<R: CryptoRngCore + ?Sized>(
         let dp = priv_key.dp().unwrap();
         let dq = priv_key.dq().unwrap();
         let qinv = priv_key.qinv().unwrap();
+        let p_params = priv_key.p_params().unwrap();
+        let q_params = priv_key.q_params().unwrap();
 
         let p = &priv_key.primes()[0];
         let q = &priv_key.primes()[1];
 
-        // TODO: store
-        let p_params = BoxedResidueParams::new(p.clone()).unwrap();
-        let q_params = BoxedResidueParams::new(q.clone()).unwrap();
-
         // precomputed: dP = (1/e) mod (p-1) = d mod (p-1)
         // precomputed: dQ = (1/e) mod (q-1) = d mod (q-1)
 
         // m1 = c^dP mod p
         let m1 = pow_mod_params(&c, &dp, p_params.clone());
         // m2 = c^dQ mod q
-        let m2 = pow_mod_params(&c, &dq, q_params);
+        let m2 = pow_mod_params(&c, &dq, q_params.clone());
 
         // precomputed: qInv = (1/q) mod p
 
diff --git a/src/key.rs b/src/key.rs
index a8e8bf34..452d6954 100644
--- a/src/key.rs
+++ b/src/key.rs
@@ -104,6 +104,9 @@ pub(crate) struct PrecomputedValues {
     pub(crate) qinv: BoxedUint,
 
     pub(crate) residue_params: BoxedResidueParams,
+
+    pub(crate) p_params: BoxedResidueParams,
+    pub(crate) q_params: BoxedResidueParams,
 }
 
 impl Zeroize for PrecomputedValues {
@@ -404,11 +407,16 @@ impl RsaPrivateKey {
         let residue_params =
             BoxedResidueParams::new(self.pubkey_components.n.clone().get()).unwrap();
 
+        let p_params = BoxedResidueParams::new(p.clone()).unwrap();
+        let q_params = BoxedResidueParams::new(q.clone()).unwrap();
+
         self.precomputed = Some(PrecomputedValues {
             dp,
             dq,
             qinv,
             residue_params,
+            p_params,
+            q_params,
         });
 
         Ok(())
@@ -535,6 +543,14 @@ impl PrivateKeyPartsNew for RsaPrivateKey {
     fn residue_params(&self) -> Option<&BoxedResidueParams> {
         self.precomputed.as_ref().map(|p| &p.residue_params)
     }
+
+    fn p_params(&self) -> Option<&BoxedResidueParams> {
+        self.precomputed.as_ref().map(|p| &p.p_params)
+    }
+
+    fn q_params(&self) -> Option<&BoxedResidueParams> {
+        self.precomputed.as_ref().map(|p| &p.q_params)
+    }
 }
 
 /// Check that the public key is well formed and has an exponent within acceptable bounds.
diff --git a/src/traits/keys.rs b/src/traits/keys.rs
index 11985856..5912ed01 100644
--- a/src/traits/keys.rs
+++ b/src/traits/keys.rs
@@ -120,6 +120,10 @@ pub trait PrivateKeyPartsNew: PublicKeyPartsNew {
     fn crt_values(&self) -> Option<&[CrtValueNew]>;
 
     fn residue_params(&self) -> Option<&BoxedResidueParams>;
+
+    fn p_params(&self) -> Option<&BoxedResidueParams>;
+
+    fn q_params(&self) -> Option<&BoxedResidueParams>;
 }
 
 /// Contains the precomputed Chinese remainder theorem values.