src/utils/dff.rs

@@ -19,6 +19,7 @@ pub fn ddf(f: Polynomial) -> Vec<(Polynomial, u128)> {
     let mut f_star = f.clone();
 
     let one_cmp = Polynomial::one();
+
     while f_star.degree() as u128 >= (2 * d) {
         let h = Polynomial::x().bpow_mod(q.clone().pow(d), f_star.clone()) + Polynomial::x();
 

src/utils/edf.rs

@@ -0,0 +1,105 @@
+use base64::{prelude::BASE64_STANDARD, Engine};
+use num::{BigUint, FromPrimitive, Integer, One};
+use rand::Rng;
+
+use crate::utils::{field::FieldElement, poly::non_monic_gcd};
+
+use super::poly::{gcd, Polynomial};
+
+pub fn edf(f: Polynomial, d: u32) -> Vec<Polynomial> {
+    eprintln!("Starting edf");
+
+    let q = BigUint::pow(&BigUint::from_u8(2).unwrap(), 128);
+    let n: u32 = (f.degree() as u32) / (d);
+    let mut z: Vec<Polynomial> = vec![f.clone()];
+    let one_cmp = Polynomial::one();
+
+    while (z.len() as u32) < n {
+        //eprintln!("z len {}", z.len());
+        //eprintln!("n len {}", n);
+
+        let h = Polynomial::rand(&rand::thread_rng().gen_range(0..f.degree()));
+        //eprintln!("h: {:02X?}", h);
+
+        let exponent = (q.pow(d) - BigUint::one()) / BigUint::from_u8(3).unwrap();
+        eprintln!("q before for {:0X?}", exponent);
+
+        let g = h.bpow_mod(exponent, &f) + Polynomial::one();
+        //eprintln!("g before for {:0X?}", g);
+
+        //eprintln!("z before for {:0X?}", z);
+
+        for i in 0..z.len() {
+            if z[i].degree() as u32 > d {
+                //eprintln!("Inside if");
+                let j = gcd(&z[i], &g);
+
+                eprintln!("j: {:02X?}", j);
+                if j != one_cmp && j != z[i] {
+                    eprintln!("Working on Z");
+                    let intemediate = z[i].div(&j).0;
+                    z.remove(i);
+                    z.push(j.clone());
+                    z.push(intemediate);
+                }
+            }
+        }
+
+        //eprintln!("z after for {:0X?}", z);
+    }
+
+    z
+}
+
+#[cfg(test)]
+mod tests {
+
+    use serde_json::json;
+
+    // Note this useful idiom: importing names from outer (for mod tests) scope.
+    use super::*;
+
+    #[test]
+    fn test_edf_sheet() {
+        let json_f = json!([
+            "mmAAAAAAAAAAAAAAAAAAAA==",
+            "AbAAAAAAAAAAAAAAAAAAAA==",
+            "zgAAAAAAAAAAAAAAAAAAAA==",
+            "FwAAAAAAAAAAAAAAAAAAAA==",
+            "AAAAAAAAAAAAAAAAAAAAAA==",
+            "wAAAAAAAAAAAAAAAAAAAAA==",
+            "gAAAAAAAAAAAAAAAAAAAAA=="
+        ]);
+        let d = 3;
+        let poly_f = Polynomial::from_c_array(&json_f);
+
+        let mut factors = edf(poly_f, d);
+        factors.sort();
+
+        let mut result: Vec<Vec<String>> = vec![];
+
+        for factor in factors {
+            result.push(factor.to_c_array())
+        }
+
+        println!("Result: {:?}", result);
+
+        assert_eq!(
+            result,
+            vec![
+                [
+                    "iwAAAAAAAAAAAAAAAAAAAA==",
+                    "CAAAAAAAAAAAAAAAAAAAAA==",
+                    "AAAAAAAAAAAAAAAAAAAAAA==",
+                    "gAAAAAAAAAAAAAAAAAAAAA=="
+                ],
+                [
+                    "kAAAAAAAAAAAAAAAAAAAAA==",
+                    "CAAAAAAAAAAAAAAAAAAAAA==",
+                    "wAAAAAAAAAAAAAAAAAAAAA==",
+                    "gAAAAAAAAAAAAAAAAAAAAA=="
+                ]
+            ]
+        )
+    }
+}

src/utils/field.rs

@@ -1,4 +1,5 @@
 use base64::prelude::*;
+use rand::{random, Rng, RngCore};
 use std::{u128, u8, usize};
 
 use std::{
@@ -24,6 +25,11 @@ impl FieldElement {
         87, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01,
     ];
 
+    pub fn rand() -> Self {
+        let rand_field: [u8; 16] = rand::random();
+        FieldElement::new(rand_field.to_vec())
+    }
+
     pub fn zero(self) -> Self {
         FieldElement::new(vec![0])
     }

src/utils/poly.rs

@@ -41,6 +41,15 @@ impl Polynomial {
         ])
     }
 
+    pub fn rand(rng_cap: &usize) -> Self {
+        let mut rand_poly: Vec<FieldElement> = Vec::with_capacity(rng_cap.to_owned());
+        for _i in 0..rng_cap.to_owned() {
+            rand_poly.push(FieldElement::rand());
+        }
+
+        Polynomial::new(rand_poly)
+    }
+
     pub fn zero() -> Self {
         Polynomial::new(vec![FieldElement::new(vec![0; 16])])
     }
@@ -141,7 +150,7 @@ impl Polynomial {
         result
     }
 
-    pub fn bpow_mod(mut self, mut exponent: BigUint, modulus: Polynomial) -> Polynomial {
+    pub fn bpow_mod(mut self, mut exponent: BigUint, modulus: &Polynomial) -> Polynomial {
         let mut result: Polynomial = Polynomial::new(vec![FieldElement::new(
             polynomial_2_block(vec![0], "gcm").unwrap(),
         )]);
@@ -572,6 +581,15 @@ pub fn gcd(a: &Polynomial, b: &Polynomial) -> Polynomial {
     return gcd(&monic_b, a);
 }
 
+pub fn non_monic_gcd(a: &Polynomial, b: &Polynomial) -> Polynomial {
+    if a.is_zero() {
+        return b.clone();
+    }
+
+    let b = b.div(&a).1;
+    return non_monic_gcd(&b, a);
+}
+
 pub fn sort_polynomial_array(mut polys: Vec<Polynomial>) -> Result<Vec<Polynomial>> {
     // Algorithm to sort polynomials
     // First sorting round