test: debug shares

src/debug_encoding.rs

@@ -0,0 +1,197 @@
+use std::array;
+use std::fmt::Debug;
+use std::ops::{self, Index};
+
+use bytemuck::Zeroable;
+
+pub const BITS: usize = 128;
+const LIMBS: usize = 2;
+
+#[repr(transparent)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)]
+pub struct SEncodedBits(pub [u16; BITS]);
+impl SEncodedBits {
+    pub fn share(&self, n: usize) -> Box<[SEncodedBits]> {
+        assert!(n > 0);
+        let mut rest = SEncodedBits::default();
+
+        for n in 0..rest.0.len() {
+            if n % 2 == 0 {
+                rest.0[n] = 1;
+            } else if n % 7 == 0 {
+                rest.0[n] = 1;
+            } else {
+                rest.0[n] = 0;
+            }
+        }
+
+        let last = &mut SEncodedBits::default();
+        // Initialize last to sum of self
+        *last = self - rest;
+
+        let result = Box::new([rest, *last]);
+        result
+    }
+}
+
+impl ops::AddAssign<&SEncodedBits> for SEncodedBits {
+    fn add_assign(&mut self, rhs: &SEncodedBits) {
+        for (s, &r) in self.0.iter_mut().zip(rhs.0.iter()) {
+            *s = s.wrapping_add(r);
+        }
+    }
+}
+
+impl ops::Add<&SEncodedBits> for SEncodedBits {
+    type Output = SEncodedBits;
+
+    fn add(mut self, rhs: &SEncodedBits) -> Self::Output {
+        self += rhs;
+        self
+    }
+}
+
+impl ops::Sub<SEncodedBits> for &SEncodedBits {
+    type Output = SEncodedBits;
+
+    fn sub(self, mut rhs: SEncodedBits) -> Self::Output {
+        for (a, &b) in rhs.0.iter_mut().zip(self.0.iter()) {
+            *a = b.wrapping_sub(*a);
+        }
+        rhs
+    }
+}
+
+impl Default for SEncodedBits {
+    fn default() -> Self {
+        Self([0; BITS])
+    }
+}
+
+impl From<&SBits> for SEncodedBits {
+    fn from(value: &SBits) -> Self {
+        SEncodedBits(array::from_fn(|i| if value[i] { 1 } else { 0 }))
+    }
+}
+
+#[repr(transparent)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub struct SBits(pub [u64; LIMBS]);
+
+impl SBits {}
+
+unsafe impl Zeroable for SBits {}
+
+impl Index<usize> for SBits {
+    type Output = bool;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        assert!(index < BITS);
+        let (limb, bit) = (index / 64, index % 64);
+        let b = self.0[limb] & (1_u64 << bit) != 0;
+        if b {
+            &true
+        } else {
+            &false
+        }
+    }
+}
+
+impl Default for SBits {
+    fn default() -> Self {
+        Self([u64::MAX; LIMBS])
+    }
+}
+
+impl Debug for SBits {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        for limb in self.0 {
+            write!(f, "{limb:016x}")?;
+        }
+        Ok(())
+    }
+}
+
+impl From<[u8; LIMBS * 8]> for SBits {
+    fn from(bytes: [u8; LIMBS * 8]) -> Self {
+        let mut limbs = [0_u64; LIMBS];
+        for (i, chunk) in bytes.array_chunks::<8>().enumerate() {
+            limbs[i] = u64::from_be_bytes(*chunk);
+        }
+        Self(limbs)
+    }
+}
+
+impl TryFrom<&[u8]> for SBits {
+    type Error = ();
+
+    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
+        if value.len() != LIMBS * 8 {
+            return Err(());
+        }
+
+        let mut limbs = [0_u64; LIMBS];
+        for (i, chunk) in value.array_chunks::<8>().enumerate() {
+            limbs[i] = u64::from_be_bytes(*chunk);
+        }
+
+        Ok(Self(limbs))
+    }
+}
+
+impl TryFrom<Vec<u8>> for SBits {
+    type Error = ();
+
+    fn try_from(value: Vec<u8>) -> Result<Self, Self::Error> {
+        Self::try_from(value.as_slice())
+    }
+}
+
+fn reconstruct_shares(shares: &[SEncodedBits], n: usize) -> SEncodedBits {
+    let mut reconstructed = shares[0].clone();
+    for share in &shares[1..n] {
+        reconstructed = reconstructed + share;
+    }
+    reconstructed
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn share_computation() {
+        let bytes: [u8; 16] = [
+            1, 2, 3, 4, 5, 8, 1, 1, // First 64-bit limb
+            1, 1, 1, 0, 0, 1, 1, 1, //  Second 64-bit limb
+        ];
+
+        // Create a Bits object from the byte array
+        let bits: SBits = SBits::from(bytes);
+        for (idx, chunk) in bits.0.iter().enumerate() {
+            println!("{:?}", chunk);
+            println!("{:?}", idx);
+        }
+
+        println!("BITS          {:?}", bits);
+        let eb = SEncodedBits::from(&bits); // Setup with static input
+
+        println!("EBITS         {:?}", eb);
+        let n = 2; // Number of shares
+                   // Replace thread_rng() with mock_rng() in the share method or here
+        let shares = eb.share(n);
+        let ebr: SEncodedBits = reconstruct_shares(&shares, n);
+        // println!("RECONSTRUCTED {:?}", ebr);
+        println!("SHARES {:?}", shares);
+        // Assert on the expected shares, determined by running with mock_rng
+        assert_eq!(eb, ebr);
+    }
+}
+
+/*
+=== RUST
+encodedBits [1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0]
+=== RUN   TestSharesNew
+encodedBits [1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0]
+=== RUN   TestSharesOld
+encodedBits [1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0]
+*/

src/lib.rs

@@ -6,6 +6,7 @@ pub mod bits;
 pub mod config;
 pub mod coordinator;
 pub mod db;
+mod debug_encoding;
 pub mod distance;
 pub mod encoded_bits;
 pub mod health_check;