From fdd6fc5d6d505d7f3cc7308abf5d8edf4f04a513 Mon Sep 17 00:00:00 2001
From: Daniel Bloom <7810950-Daniel.Aaron.Bloom@users.noreply.gitlab.com>
Date: Mon, 26 Dec 2022 18:40:59 -0800
Subject: [PATCH 1/7] feat: support zeroize codegen

---
 Cargo.toml           | 11 +++++++++--
 ff_derive/Cargo.toml |  2 ++
 ff_derive/src/lib.rs | 19 +++++++++++++++++++
 tests/derive_zero.rs | 28 ++++++++++++++++++++++++++++
 4 files changed, 58 insertions(+), 2 deletions(-)
 create mode 100644 tests/derive_zero.rs

diff --git a/Cargo.toml b/Cargo.toml
index 95ee2b9..68cfbdf 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,9 +16,10 @@ edition = "2021"
 [dependencies]
 bitvec = { version = "1", default-features = false, optional = true }
 byteorder = { version = "1", default-features = false, optional = true }
-ff_derive = { version = "0.13", path = "ff_derive", optional = true }
+ff_derive = { version = "0.13.0", path = "ff_derive", optional = true }
 rand_core = { version = "0.6", default-features = false }
 subtle = { version = "2.2.1", default-features = false, features = ["i128"] }
+zeroize = { version = "1", default-features = false, optional = true }
 
 [dev-dependencies]
 blake2b_simd = "1"
@@ -28,16 +29,22 @@ rand = "0.8"
 default = ["bits", "std"]
 alloc = []
 bits = ["bitvec"]
+zero = ["zeroize"]
 derive = ["byteorder", "ff_derive"]
 std = ["alloc"]
 # with MSRV 1.60 this could be merged into bits with ff_derive?/bits
 # see PR#72 for more information.
-derive_bits = ["bits", "ff_derive/bits"]
+derive_bits = ["bits", "derive", "ff_derive/bits"]
+derive_zero = ["zero", "derive", "ff_derive/zero"]
 
 [[test]]
 name = "derive"
 required-features = ["derive"]
 
+[[test]]
+name = "derive_zero"
+required-features = ["derive_zero"]
+
 [badges]
 maintenance = { status = "actively-developed" }
 
diff --git a/ff_derive/Cargo.toml b/ff_derive/Cargo.toml
index 68f5fe2..e155a10 100644
--- a/ff_derive/Cargo.toml
+++ b/ff_derive/Cargo.toml
@@ -15,6 +15,8 @@ edition = "2021"
 [features]
 # enabled when generating bitvec code utilizing the version of ff's bitvec
 bits = []
+# enabled when generating zeroize code utilizing the version of ff's zeroize
+zero = []
 
 [lib]
 proc-macro = true
diff --git a/ff_derive/src/lib.rs b/ff_derive/src/lib.rs
index 5e7ebb6..143b4e6 100644
--- a/ff_derive/src/lib.rs
+++ b/ff_derive/src/lib.rs
@@ -332,6 +332,14 @@ fn prime_field_repr_impl(
 ) -> proc_macro2::TokenStream {
     let repr_iter_be = endianness.iter_be();
 
+    let prime_field_repr_zero_impl = if cfg!(feature = "zero") {
+        Some(quote! {
+            impl ::zeroize::DefaultIsZeroes for #repr {}
+        })
+    } else {
+        None
+    };
+
     quote! {
         #[derive(Copy, Clone)]
         pub struct #repr(pub [u8; #bytes]);
@@ -386,6 +394,8 @@ fn prime_field_repr_impl(
                 &mut self.0
             }
         }
+
+        #prime_field_repr_zero_impl
     }
 }
 
@@ -942,6 +952,14 @@ fn prime_field_impl(
         }
     };
 
+    let prime_field_zero_impl = if cfg!(feature = "zero") {
+        Some(quote! {
+            impl ::zeroize::DefaultIsZeroes for #name {}
+        })
+    } else {
+        None
+    };
+
     let top_limb_index = limbs - 1;
 
     quote! {
@@ -1261,6 +1279,7 @@ fn prime_field_impl(
         }
 
         #prime_field_bits_impl
+        #prime_field_zero_impl
 
         impl ::ff::Field for #name {
             const ZERO: Self = #name([0; #limbs]);
diff --git a/tests/derive_zero.rs b/tests/derive_zero.rs
new file mode 100644
index 0000000..982e001
--- /dev/null
+++ b/tests/derive_zero.rs
@@ -0,0 +1,28 @@
+//! This module exercises the `ff_derive` procedural macros, specifically to ensure
+//! zeroize works
+
+#[macro_use]
+extern crate ff;
+
+/// The BLS12-381 scalar field.
+#[derive(PrimeField)]
+#[PrimeFieldModulus = "52435875175126190479447740508185965837690552500527637822603658699938581184513"]
+#[PrimeFieldGenerator = "7"]
+#[PrimeFieldReprEndianness = "little"]
+struct Bls381K12Scalar([u64; 4]);
+
+#[test]
+fn zeroize() {
+    use ff::{Field, PrimeField};
+    use rand::rngs::OsRng;
+    use zeroize::Zeroize;
+
+    let mut f = Bls381K12Scalar::random(OsRng);
+    let mut r = f.to_repr();
+
+    f.zeroize();
+    assert_eq!(f, Bls381K12Scalar::ZERO);
+
+    r.zeroize();
+    assert_eq!(r, Default::default());
+}

From 3b717a178a96c8d48371bad66963658940bb41d9 Mon Sep 17 00:00:00 2001
From: Daniel-Aaron-Bloom
 <76709210+Daniel-Aaron-Bloom@users.noreply.github.com>
Date: Thu, 29 Dec 2022 09:17:50 -0800
Subject: [PATCH 2/7] Update Cargo.toml

Co-authored-by: str4d <thestr4d@gmail.com>
---
 Cargo.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index 68cfbdf..a17053c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,7 +16,7 @@ edition = "2021"
 [dependencies]
 bitvec = { version = "1", default-features = false, optional = true }
 byteorder = { version = "1", default-features = false, optional = true }
-ff_derive = { version = "0.13.0", path = "ff_derive", optional = true }
+ff_derive = { version = "0.13", path = "ff_derive", optional = true }
 rand_core = { version = "0.6", default-features = false }
 subtle = { version = "2.2.1", default-features = false, features = ["i128"] }
 zeroize = { version = "1", default-features = false, optional = true }

From a6be620b6afbf7ca151ac8af1e3f4c35b7758f95 Mon Sep 17 00:00:00 2001
From: Daniel-Aaron-Bloom
 <76709210+Daniel-Aaron-Bloom@users.noreply.github.com>
Date: Thu, 29 Dec 2022 09:32:09 -0800
Subject: [PATCH 3/7] rename `zero` feature to `zeroize` as per Code Review

Co-authored-by: str4d <thestr4d@gmail.com>
---
 ff_derive/Cargo.toml | 2 +-
 ff_derive/src/lib.rs | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/ff_derive/Cargo.toml b/ff_derive/Cargo.toml
index e155a10..61d7ad8 100644
--- a/ff_derive/Cargo.toml
+++ b/ff_derive/Cargo.toml
@@ -16,7 +16,7 @@ edition = "2021"
 # enabled when generating bitvec code utilizing the version of ff's bitvec
 bits = []
 # enabled when generating zeroize code utilizing the version of ff's zeroize
-zero = []
+zeroize = []
 
 [lib]
 proc-macro = true
diff --git a/ff_derive/src/lib.rs b/ff_derive/src/lib.rs
index 143b4e6..8450dd1 100644
--- a/ff_derive/src/lib.rs
+++ b/ff_derive/src/lib.rs
@@ -332,7 +332,7 @@ fn prime_field_repr_impl(
 ) -> proc_macro2::TokenStream {
     let repr_iter_be = endianness.iter_be();
 
-    let prime_field_repr_zero_impl = if cfg!(feature = "zero") {
+    let prime_field_repr_zeroize_impl = if cfg!(feature = "zeroize") {
         Some(quote! {
             impl ::zeroize::DefaultIsZeroes for #repr {}
         })
@@ -395,7 +395,7 @@ fn prime_field_repr_impl(
             }
         }
 
-        #prime_field_repr_zero_impl
+        #prime_field_repr_zeroize_impl
     }
 }
 
@@ -952,7 +952,7 @@ fn prime_field_impl(
         }
     };
 
-    let prime_field_zero_impl = if cfg!(feature = "zero") {
+    let prime_field_zeroize_impl = if cfg!(feature = "zeroize") {
         Some(quote! {
             impl ::zeroize::DefaultIsZeroes for #name {}
         })
@@ -1279,7 +1279,7 @@ fn prime_field_impl(
         }
 
         #prime_field_bits_impl
-        #prime_field_zero_impl
+        #prime_field_zeroize_impl
 
         impl ::ff::Field for #name {
             const ZERO: Self = #name([0; #limbs]);

From a42c8b562daa55cf6d26f02b4963fbd7f0717128 Mon Sep 17 00:00:00 2001
From: Daniel Bloom <7810950-Daniel.Aaron.Bloom@users.noreply.gitlab.com>
Date: Thu, 29 Dec 2022 09:36:20 -0800
Subject: [PATCH 4/7] Move tests as per Code Review

---
 Cargo.toml           |  6 +-----
 tests/derive.rs      | 18 ++++++++++++++++++
 tests/derive_zero.rs | 28 ----------------------------
 3 files changed, 19 insertions(+), 33 deletions(-)
 delete mode 100644 tests/derive_zero.rs

diff --git a/Cargo.toml b/Cargo.toml
index a17053c..c22e875 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -35,16 +35,12 @@ std = ["alloc"]
 # with MSRV 1.60 this could be merged into bits with ff_derive?/bits
 # see PR#72 for more information.
 derive_bits = ["bits", "derive", "ff_derive/bits"]
-derive_zero = ["zero", "derive", "ff_derive/zero"]
+derive_zero = ["zero", "derive", "ff_derive/zeroize"]
 
 [[test]]
 name = "derive"
 required-features = ["derive"]
 
-[[test]]
-name = "derive_zero"
-required-features = ["derive_zero"]
-
 [badges]
 maintenance = { status = "actively-developed" }
 
diff --git a/tests/derive.rs b/tests/derive.rs
index fa6ee20..9c1f106 100644
--- a/tests/derive.rs
+++ b/tests/derive.rs
@@ -135,3 +135,21 @@ fn batch_inversion() {
         }
     }
 }
+
+#[cfg(feature = "zero")]
+
+#[test]
+fn zeroize() {
+    use ff::{Field, PrimeField};
+    use rand::rngs::OsRng;
+    use zeroize::Zeroize;
+
+    let mut f = Bls381K12Scalar::random(OsRng);
+    let mut r = f.to_repr();
+
+    f.zeroize();
+    assert_eq!(f, Bls381K12Scalar::ZERO);
+
+    r.zeroize();
+    assert_eq!(r, Default::default());
+}
\ No newline at end of file
diff --git a/tests/derive_zero.rs b/tests/derive_zero.rs
deleted file mode 100644
index 982e001..0000000
--- a/tests/derive_zero.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-//! This module exercises the `ff_derive` procedural macros, specifically to ensure
-//! zeroize works
-
-#[macro_use]
-extern crate ff;
-
-/// The BLS12-381 scalar field.
-#[derive(PrimeField)]
-#[PrimeFieldModulus = "52435875175126190479447740508185965837690552500527637822603658699938581184513"]
-#[PrimeFieldGenerator = "7"]
-#[PrimeFieldReprEndianness = "little"]
-struct Bls381K12Scalar([u64; 4]);
-
-#[test]
-fn zeroize() {
-    use ff::{Field, PrimeField};
-    use rand::rngs::OsRng;
-    use zeroize::Zeroize;
-
-    let mut f = Bls381K12Scalar::random(OsRng);
-    let mut r = f.to_repr();
-
-    f.zeroize();
-    assert_eq!(f, Bls381K12Scalar::ZERO);
-
-    r.zeroize();
-    assert_eq!(r, Default::default());
-}

From 82485154ed9694073472668e84efa92ae147aad2 Mon Sep 17 00:00:00 2001
From: Daniel Bloom <7810950-Daniel.Aaron.Bloom@users.noreply.gitlab.com>
Date: Thu, 29 Dec 2022 09:37:45 -0800
Subject: [PATCH 5/7] cargo fmt

---
 tests/derive.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tests/derive.rs b/tests/derive.rs
index 9c1f106..6d87258 100644
--- a/tests/derive.rs
+++ b/tests/derive.rs
@@ -137,7 +137,6 @@ fn batch_inversion() {
 }
 
 #[cfg(feature = "zero")]
-
 #[test]
 fn zeroize() {
     use ff::{Field, PrimeField};
@@ -152,4 +151,4 @@ fn zeroize() {
 
     r.zeroize();
     assert_eq!(r, Default::default());
-}
\ No newline at end of file
+}

From b8e716ba1cb0e6e0ad72e46f99183f1614e748fc Mon Sep 17 00:00:00 2001
From: Daniel-Aaron-Bloom
 <76709210+Daniel-Aaron-Bloom@users.noreply.github.com>
Date: Thu, 29 Dec 2022 21:33:46 -0800
Subject: [PATCH 6/7] Apply suggestions from code review

Co-authored-by: str4d <thestr4d@gmail.com>
---
 Cargo.toml           | 2 --
 ff_derive/Cargo.toml | 2 +-
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index c22e875..243465a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,7 +19,6 @@ byteorder = { version = "1", default-features = false, optional = true }
 ff_derive = { version = "0.13", path = "ff_derive", optional = true }
 rand_core = { version = "0.6", default-features = false }
 subtle = { version = "2.2.1", default-features = false, features = ["i128"] }
-zeroize = { version = "1", default-features = false, optional = true }
 
 [dev-dependencies]
 blake2b_simd = "1"
@@ -29,7 +28,6 @@ rand = "0.8"
 default = ["bits", "std"]
 alloc = []
 bits = ["bitvec"]
-zero = ["zeroize"]
 derive = ["byteorder", "ff_derive"]
 std = ["alloc"]
 # with MSRV 1.60 this could be merged into bits with ff_derive?/bits
diff --git a/ff_derive/Cargo.toml b/ff_derive/Cargo.toml
index 61d7ad8..d0a41dd 100644
--- a/ff_derive/Cargo.toml
+++ b/ff_derive/Cargo.toml
@@ -15,7 +15,7 @@ edition = "2021"
 [features]
 # enabled when generating bitvec code utilizing the version of ff's bitvec
 bits = []
-# enabled when generating zeroize code utilizing the version of ff's zeroize
+# enabled when generating zeroize bindings
 zeroize = []
 
 [lib]

From 08afa04041f713b198f75487ce8f7b2986becdbc Mon Sep 17 00:00:00 2001
From: Daniel Bloom <7810950-Daniel.Aaron.Bloom@users.noreply.gitlab.com>
Date: Thu, 29 Dec 2022 21:41:39 -0800
Subject: [PATCH 7/7] fixup tests

---
 Cargo.toml      | 3 ++-
 tests/derive.rs | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 243465a..a53e367 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,6 +23,7 @@ subtle = { version = "2.2.1", default-features = false, features = ["i128"] }
 [dev-dependencies]
 blake2b_simd = "1"
 rand = "0.8"
+zeroize = { version = "1", default-features = false }
 
 [features]
 default = ["bits", "std"]
@@ -33,7 +34,7 @@ std = ["alloc"]
 # with MSRV 1.60 this could be merged into bits with ff_derive?/bits
 # see PR#72 for more information.
 derive_bits = ["bits", "derive", "ff_derive/bits"]
-derive_zero = ["zero", "derive", "ff_derive/zeroize"]
+test_derive_zeroize = ["derive", "ff_derive/zeroize"]
 
 [[test]]
 name = "derive"
diff --git a/tests/derive.rs b/tests/derive.rs
index 6d87258..81ac505 100644
--- a/tests/derive.rs
+++ b/tests/derive.rs
@@ -136,7 +136,7 @@ fn batch_inversion() {
     }
 }
 
-#[cfg(feature = "zero")]
+#[cfg(feature = "test_derive_zeroize")]
 #[test]
 fn zeroize() {
     use ff::{Field, PrimeField};