From cb28a528e8378762cbaed901ac575477bb4fd4de Mon Sep 17 00:00:00 2001
From: David Florness <david@florness.com>
Date: Sun, 10 Nov 2019 07:02:49 -0700
Subject: [PATCH] Endpoint to submit signed ballot

---
 main.rkt   | 19 ++++++++++++++++---
 server.rkt | 23 +++++++++++++++++------
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/main.rkt b/main.rkt
index 994c648..9b42422 100644
--- a/main.rkt
+++ b/main.rkt
@@ -43,15 +43,28 @@
         r
         (gen))))
 
+(displayln "creating blinded message...")
+
 (define M (modulo (* m (expt r e)) n))
 
+(displayln "asking for blinded signature...")
+
 (define S (bytes->integer
            (port->bytes (post-pure-port (vohea-url "/sign")
                                         (integer->bytes M (/ keylen 8) #f)))
            #f))
 
+(displayln "computing real signature")
+
 (define s (modulo (* S (modular-inverse r n)) n))
 
-(displayln (list (equal? m (modular-expt s e n))
-                 m
-                 (modular-expt s e n)))
+(displayln "submitting signed ballot...")
+
+(define result (bytes->string/utf-8
+                (port->bytes
+                 (post-pure-port (vohea-url "/vote")
+                                 (bytes-append (integer->bytes m (/ keylen 8) #f)
+                                               (integer->bytes s (/ keylen 8) #f)
+                                               )))))
+
+(displayln result)
diff --git a/server.rkt b/server.rkt
index d3a6c44..d8bde42 100644
--- a/server.rkt
+++ b/server.rkt
@@ -10,6 +10,8 @@
 
 (define cands (list "ohea" "rtsn" "qfuy"))
 (define k (gen-key))
+(define n (car k))
+(define d (cdr k))
 
 ; how this is not a provided function is beyond me
 (define/contract (response/json jsexpr)
@@ -18,29 +20,38 @@
    200 #f (current-seconds) #"application/json"
    empty (list (jsexpr->bytes jsexpr))))
 
+(define/contract (response/text txt)
+  (-> string? response?)
+  (response/full
+   200 #f (current-seconds) #"text/plain"
+   empty (list (string->bytes/utf-8 txt))))
+
 (define (candidates req)
   (response/json cands))
 
 (define (vote req)
-  (response/xexpr
-   '(html (body (p "you're going to vote")))))
+  (let* ([data (request-post-data/raw req)]
+         [m (bytes->integer (subbytes data 0 (/ keylen 8)) #f)]
+         [s (bytes->integer (subbytes data (/ keylen 8) (* 2 (/ keylen 8))) #f)])
+    (if (equal? m (modular-expt s e n))
+        (response/text "vote submitted")
+        (response/text "invalid signature"))))
 
 (define (sign req)
-  (println (request-post-data/raw req))
   (let ([m (bytes->integer (request-post-data/raw req) #f)])
     (response/full
      200 #f (current-seconds) #"application/octet-stream"
-     empty (list (integer->bytes (modular-expt m (cdr k) (car k)) (/ keylen 8) #f)))))
+     empty (list (integer->bytes (modular-expt m d n) (/ keylen 8) #f)))))
 
 (define (key req)
   (response/full
    200 #f (current-seconds) #"application/octet-stream"
-   empty (list (integer->bytes (car k) (/ keylen 8) #f))))
+   empty (list (integer->bytes n (/ keylen 8) #f))))
 
 (define-values (dispatcher url-generator)
   (dispatch-rules
    [("candidates") candidates]
-   [("vote") vote]
+   [("vote") #:method "post" vote]
    [("sign") #:method "post" sign]
    [("key") key]
    [else candidates]))
-- 
2.38.4