From 253dfde60e6106ceeda696b86cb2f605ce3cd557 Mon Sep 17 00:00:00 2001
From: derekpierre <derek.pierre@gmail.com>
Date: Tue, 6 Jun 2023 11:11:31 -0400
Subject: [PATCH] Remove unnecessary/excession make_factory method from
 SessionSecretFactory.

---
 .../nucypher_core/__init__.pyi                |  4 ----
 nucypher-core-python/src/lib.rs               |  6 ------
 nucypher-core-wasm/src/lib.rs                 |  5 -----
 nucypher-core/src/dkg.rs                      | 19 ++++++++-----------
 4 files changed, 8 insertions(+), 26 deletions(-)

diff --git a/nucypher-core-python/nucypher_core/__init__.pyi b/nucypher-core-python/nucypher_core/__init__.pyi
index e96c3263..fce1d08b 100644
--- a/nucypher-core-python/nucypher_core/__init__.pyi
+++ b/nucypher-core-python/nucypher_core/__init__.pyi
@@ -534,7 +534,3 @@ class SessionSecretFactory:
 
     def make_key(self, label: bytes) -> SessionStaticSecret:
         ...
-
-    def make_factory(self, label: bytes) -> RequestKeyFactory:
-        ...
-
diff --git a/nucypher-core-python/src/lib.rs b/nucypher-core-python/src/lib.rs
index 63b84d8e..5aa09c55 100644
--- a/nucypher-core-python/src/lib.rs
+++ b/nucypher-core-python/src/lib.rs
@@ -737,12 +737,6 @@ impl SessionSecretFactory {
         }
     }
 
-    pub fn make_factory(&self, label: &[u8]) -> SessionSecretFactory {
-        SessionSecretFactory {
-            backend: self.backend.make_factory(label),
-        }
-    }
-
     fn __str__(&self) -> String {
         self.backend.to_string()
     }
diff --git a/nucypher-core-wasm/src/lib.rs b/nucypher-core-wasm/src/lib.rs
index a4ca38ec..a84f4fc3 100644
--- a/nucypher-core-wasm/src/lib.rs
+++ b/nucypher-core-wasm/src/lib.rs
@@ -633,11 +633,6 @@ impl SessionSecretFactory {
         SessionStaticSecret(self.0.make_key(label))
     }
 
-    #[wasm_bindgen(js_name = makeFactory)]
-    pub fn make_factory(&self, label: &[u8]) -> Self {
-        Self(self.0.make_factory(label))
-    }
-
     #[allow(clippy::inherent_to_string)]
     #[wasm_bindgen(js_name = toString)]
     pub fn to_string(&self) -> String {
diff --git a/nucypher-core/src/dkg.rs b/nucypher-core/src/dkg.rs
index 564eed1e..3ca231cf 100644
--- a/nucypher-core/src/dkg.rs
+++ b/nucypher-core/src/dkg.rs
@@ -264,6 +264,7 @@ pub mod session {
     type SessionSecretFactorySeed = GenericArray<u8, SessionSecretFactorySeedSize>;
 
     /// Error thrown when invalid random seed provided for creating key factory.
+    #[derive(Debug)]
     pub struct InvalidSessionSecretFactorySeedLength;
 
     impl fmt::Display for InvalidSessionSecretFactorySeedLength {
@@ -319,14 +320,6 @@ pub mod session {
                 ChaCha20Rng::from_seed(<[u8; 32]>::try_from(seed.as_secret().as_slice()).unwrap());
             SessionStaticSecret::random_from_rng(&mut rng)
         }
-
-        /// Creates a `SessionSecretFactory` deterministically from the given label.
-        pub fn make_factory(&self, label: &[u8]) -> Self {
-            let prefix = b"SESSION_SECRET_FACTORY_DERIVATION/";
-            let info = [prefix, label].concat();
-            let derived_seed = kdf::<SessionSecretFactorySeedSize>(self.0.as_secret(), Some(&info));
-            Self(derived_seed)
-        }
     }
 
     impl fmt::Display for SessionSecretFactory {
@@ -590,6 +583,7 @@ mod tests {
     };
 
     use generic_array::typenum::Unsigned;
+    use rand_core::RngCore;
 
     use crate::dkg::session::SessionStaticSecret;
     use crate::dkg::{
@@ -652,9 +646,12 @@ mod tests {
         assert_ne!(requester_public_key, not_same_requester_public_key);
 
         // ensure that two secret factories with the same seed generate the same keys
-        let secret_factory_label = b"seeded_secret_factory_label".to_vec().into_boxed_slice();
-        let seeded_secret_factory_1 = secret_factory.make_factory(&secret_factory_label.as_ref());
-        let seeded_secret_factory_2 = secret_factory.make_factory(&secret_factory_label.as_ref());
+        let mut secret_factory_seed = [0u8; 32];
+        rand::thread_rng().fill_bytes(&mut secret_factory_seed);
+        let seeded_secret_factory_1 =
+            SessionSecretFactory::from_secure_randomness(&secret_factory_seed).unwrap();
+        let seeded_secret_factory_2 =
+            SessionSecretFactory::from_secure_randomness(&secret_factory_seed).unwrap();
 
         let key_label = b"seeded_factory_key_label".to_vec().into_boxed_slice();
         let sk_1 = seeded_secret_factory_1.make_key(&key_label);