From 2a2e10d3e094a6f221b812162a2935e6464adee5 Mon Sep 17 00:00:00 2001
From: Sean Bowe <ewillbefull@gmail.com>
Date: Sat, 17 Sep 2016 14:48:08 -0600
Subject: [PATCH] Added simulator binary for R1CS.

---
 Cargo.toml              |  6 +++++
 src/protocol/mod.rs     |  1 +
 src/protocol/secrets.rs |  8 +++---
 src/simulator.rs        | 56 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 67 insertions(+), 4 deletions(-)
 create mode 100644 src/simulator.rs

diff --git a/Cargo.toml b/Cargo.toml
index 3239242..989bb14 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,6 +21,12 @@ path = "src/verifier.rs"
 # avoid duplicate tests
 test = false
 
+[[bin]]
+name = "simulator"
+path = "src/simulator.rs"
+# avoid duplicate tests
+test = false
+
 [[bin]]
 name = "player"
 path = "src/player.rs"
diff --git a/src/protocol/mod.rs b/src/protocol/mod.rs
index a29bbc3..b928332 100644
--- a/src/protocol/mod.rs
+++ b/src/protocol/mod.rs
@@ -226,6 +226,7 @@ pub struct Stage3Contents {
 }
 
 impl Stage3Contents {
+    #[cfg(feature = "snark")]
     pub fn new(cs: &CS, stage2: &Stage2Contents) -> Self {
         assert_eq!(stage2.pk_a.len(), cs.num_vars + 1);
         assert_eq!(stage2.pk_b_temp.len(), cs.num_vars + 1);
diff --git a/src/protocol/secrets.rs b/src/protocol/secrets.rs
index 334785e..056b77d 100644
--- a/src/protocol/secrets.rs
+++ b/src/protocol/secrets.rs
@@ -1,7 +1,7 @@
 use bn::*;
 use rand::Rng;
 use super::spair::{Spair, same_power};
-#[cfg(test)]
+#[cfg(feature = "snark")]
 use snark::*;
 use rustc_serialize::{Encodable, Encoder, Decodable, Decoder};
 
@@ -205,7 +205,7 @@ impl PrivateKey {
 
     /// Construct a "blank" private key for accumulating
     /// in tests.
-    #[cfg(test)]
+    #[cfg(feature = "snark")]
     pub fn new_blank() -> PrivateKey {
         PrivateKey {
             tau: Fr::one(),
@@ -219,7 +219,7 @@ impl PrivateKey {
         }
     }
 
-    #[cfg(test)]
+    #[cfg(feature = "snark")]
     pub fn multiply(&mut self, other: &Self) {
         self.tau = self.tau * other.tau;
         self.alpha_a = self.alpha_a * other.alpha_a;
@@ -231,7 +231,7 @@ impl PrivateKey {
         self.gamma = self.gamma * other.gamma;
     }
 
-    #[cfg(test)]
+    #[cfg(feature = "snark")]
     pub fn libsnark_keypair(&self, cs: &CS) -> Keypair {
         Keypair::generate(
             cs,
diff --git a/src/simulator.rs b/src/simulator.rs
new file mode 100644
index 0000000..ea89368
--- /dev/null
+++ b/src/simulator.rs
@@ -0,0 +1,56 @@
+extern crate bn;
+extern crate rand;
+extern crate snark;
+extern crate crossbeam;
+extern crate rustc_serialize;
+
+mod protocol;
+use protocol::*;
+use snark::*;
+
+pub const THREADS: usize = 128;
+
+fn main() {
+    let rng = &mut ::rand::thread_rng();
+
+    let privkeys: Vec<_> = (0..3).map(|_| PrivateKey::new(rng)).collect();
+    let pubkeys: Vec<_> = privkeys.iter().map(|p| p.pubkey(rng)).collect();
+
+    let cs = CS::from_file();
+
+    // Stage 1
+    let mut stage1 = Stage1Contents::new(&cs);
+
+    for (private, public) in privkeys.iter().zip(pubkeys.iter()) {
+        let prev = stage1.clone();
+        stage1.transform(private);
+        assert!(stage1.verify_transform(&prev, public));
+    }
+
+    // Stage 2
+    let mut stage2 = Stage2Contents::new(&cs, &stage1);
+    for (private, public) in privkeys.iter().zip(pubkeys.iter()) {
+        let prev = stage2.clone();
+        stage2.transform(private);
+        assert!(stage2.verify_transform(&prev, public));
+    }
+
+    // Stage 3
+    let mut stage3 = Stage3Contents::new(&cs, &stage2);
+    for (private, public) in privkeys.iter().zip(pubkeys.iter()) {
+        let prev = stage3.clone();
+        stage3.transform(private);
+        assert!(stage3.verify_transform(&prev, public));
+    }
+
+    let kp = keypair(&cs, &stage1, &stage2, &stage3);
+
+    // Compare to libsnark
+
+    let mut acc = PrivateKey::new_blank();
+    for private in privkeys.iter() {
+        acc.multiply(private);
+    }
+
+    assert!(kp == acc.libsnark_keypair(&cs));
+}