From f743be23b14b639226f444e52cd50b9f0f7f4638 Mon Sep 17 00:00:00 2001
From: David Florness <david@florness.com>
Date: Sun, 23 Feb 2020 09:19:09 -0700
Subject: [PATCH] Functionality to convert polynomials to merkle trees

It's taking 12 seconds for just 100000 points :(
---
 merkle.rkt | 18 ++++++++----------
 poly.rkt   | 17 ++++++++++++++---
 2 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/merkle.rkt b/merkle.rkt
index 3dac588..2eb2330 100644
--- a/merkle.rkt
+++ b/merkle.rkt
@@ -2,13 +2,13 @@
 (require/typed sha [sha256 (-> Bytes Bytes)])
 
 (struct merkle-tree
-  ([root        : merkle-node]
-   [leaves      : (Vectorof merkle-node)]))
+  ([root    : merkle-node]
+   [leaves  : (Vectorof merkle-node)]
+   [content : (Vectorof Bytes)]))
 
 (struct merkle-node
   ([parent : (Option merkle-node)]
-   [hsh    : Bytes]
-   [C      : (Option Bytes)])
+   [hsh    : Bytes])
   #:mutable
   #:transparent)
 
@@ -17,9 +17,8 @@
          [leaves
           (build-vector (+ n (modulo n 2))
                         (λ ([i : Natural])
-                          (let ([bstr
-                                 (vector-ref content (min i (sub1 n)))])
-                            (merkle-node #f (sha256 bstr) bstr))))])
+                          (let ([bstr (vector-ref content (min i (sub1 n)))])
+                            (merkle-node #f (sha256 bstr)))))])
     (let build-level : merkle-tree
          ([nodes : (Vectorof merkle-node)
                  leaves])
@@ -33,11 +32,10 @@
                          (merkle-node
                           #f
                           (sha256 (bytes-append (merkle-node-hsh left)
-                                                (merkle-node-hsh right)))
-                          #f)])
+                                                (merkle-node-hsh right))))])
                     (set-merkle-node-parent! left new-node)
                     (set-merkle-node-parent! right new-node)
                     new-node)))
-               (merkle-tree (vector-ref nodes 0) leaves))))))
+               (merkle-tree (vector-ref nodes 0) leaves content))))))
 
 (provide (all-defined-out))
diff --git a/poly.rkt b/poly.rkt
index 943f3c4..1d26167 100644
--- a/poly.rkt
+++ b/poly.rkt
@@ -1,11 +1,16 @@
-#lang typed/racket
+#lang typed/racket/base
+(require (only-in racket/math natural?))
+(require (only-in racket/vector vector-map))
 (require/typed binaryio
   [bytes->integer (->* (Bytes Boolean) (Boolean Natural Natural) Integer)]
-  [integer->bytes (->* (Integer Natural Boolean) (Boolean Bytes Natural) Bytes)]
-  [integer-bytes-length (Integer Boolean -> Natural)])
+  [integer->bytes (->* (Integer Positive-Integer Boolean)
+                       (Boolean Bytes Natural) Bytes)]
+  [integer-bytes-length (Integer Boolean -> Positive-Integer)])
 (require/typed crypto
   [crypto-random-bytes (Natural -> Bytes)])
 
+(require "merkle.rkt")
+
 (define-type Poly (Integer -> Integer))
 
 (define (gen)
@@ -21,4 +26,10 @@
                   (* (expt x (add1 i)) (vector-ref coefficients i))))
              Integer))))
 
+(define (poly-merkle [p : Poly]) : merkle-tree
+  (merkle
+   (vector-map
+    (λ ([x : Integer]) (integer->bytes x (integer-bytes-length x #t) #t))
+    (build-vector 100000 p))))
+
 (provide (all-defined-out))
-- 
2.38.4