From 5b5143afcb70ed7ef76f3dff97c7b5c65a5fa6f4 Mon Sep 17 00:00:00 2001
From: Michael Straka <mstraka100@gmail.com>
Date: Thu, 10 Jun 2021 13:16:40 -0700
Subject: [PATCH] Subgroup check skip (#79)

* added skip subgroup check option

* changed subgroup check parameter

* added no option to SubgroupCheckMode

* cargo fmt
---
 phase1/src/helpers/accumulator.rs | 6 ++++--
 phase1/src/verification.rs        | 1 +
 setup-utils/src/elements.rs       | 7 +++++--
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/phase1/src/helpers/accumulator.rs b/phase1/src/helpers/accumulator.rs
index 66a7d7bd..f9366014 100644
--- a/phase1/src/helpers/accumulator.rs
+++ b/phase1/src/helpers/accumulator.rs
@@ -100,10 +100,12 @@ cfg_if! {
                 compression,
                 CheckForCorrectness::OnlyNonZero,
             )?;
+
             const SECURITY_PARAM: usize = 128;
             const BATCH_SIZE: usize = 1 << 12;
             let now = std::time::Instant::now();
-            let all_in_prime_order_subgroup = match (elements.len() > BATCH_SIZE, subgroup_check_mode) {
+            let prime_order_subgroup_check_pass = match (elements.len() > BATCH_SIZE, subgroup_check_mode) {
+                (_, SubgroupCheckMode::No) => true,
                 (true, SubgroupCheckMode::Auto) | (_, SubgroupCheckMode::Batched) => {
                     match batch_verify_in_subgroup(elements, SECURITY_PARAM, &mut rand::thread_rng()) {
                         Ok(()) => true,
@@ -122,7 +124,7 @@ cfg_if! {
                 }
             };
             debug!("Subgroup verification for {} elems: {}us", end - start, now.elapsed().as_micros());
-            if !all_in_prime_order_subgroup {
+            if !prime_order_subgroup_check_pass {
                 return Err(Error::IncorrectSubgroup);
             }
             Ok(())
diff --git a/phase1/src/verification.rs b/phase1/src/verification.rs
index a1ad23a9..54e627f4 100644
--- a/phase1/src/verification.rs
+++ b/phase1/src/verification.rs
@@ -381,6 +381,7 @@ impl<'a, E: PairingEngine + Sync> Phase1<'a, E> {
                                     .expect(
                                         "could not check element are non zero and in prime order subgroup (beta g1)",
                                     );
+
                                     if ratio_check {
                                         check_power_ratios::<E>(
                                             (beta_g1, compressed_output, CheckForCorrectness::No),
diff --git a/setup-utils/src/elements.rs b/setup-utils/src/elements.rs
index 8c5c0fe9..ac49a51f 100644
--- a/setup-utils/src/elements.rs
+++ b/setup-utils/src/elements.rs
@@ -90,6 +90,7 @@ pub enum SubgroupCheckMode {
     Auto,
     Direct,
     Batched,
+    No,
 }
 
 impl fmt::Display for SubgroupCheckMode {
@@ -98,6 +99,7 @@ impl fmt::Display for SubgroupCheckMode {
             SubgroupCheckMode::Auto => write!(f, "Auto"),
             SubgroupCheckMode::Direct => write!(f, "Direct"),
             SubgroupCheckMode::Batched => write!(f, "Batched"),
+            SubgroupCheckMode::No => write!(f, "No"),
         }
     }
 }
@@ -135,7 +137,8 @@ pub fn check_subgroup<C: AffineCurve>(
 ) -> core::result::Result<(), Error> {
     const SECURITY_PARAM: usize = 128;
     const BATCH_SIZE: usize = 1 << 12;
-    let all_in_prime_order_subgroup = match (elements.len() > BATCH_SIZE, subgroup_check_mode) {
+    let prime_order_subgroup_check_pass = match (elements.len() > BATCH_SIZE, subgroup_check_mode) {
+        (_, SubgroupCheckMode::No) => true,
         (true, SubgroupCheckMode::Auto) | (_, SubgroupCheckMode::Batched) => {
             match batch_verify_in_subgroup(elements, SECURITY_PARAM, &mut rand::thread_rng()) {
                 Ok(()) => true,
@@ -147,7 +150,7 @@ pub fn check_subgroup<C: AffineCurve>(
                 .is_zero()
         }),
     };
-    if !all_in_prime_order_subgroup {
+    if !prime_order_subgroup_check_pass {
         return Err(Error::IncorrectSubgroup);
     }