2 files changed, 62 insertions(+), 47 deletions(-)

M bulletin.rkt
M client.rkt

@@ 2,6 2,7 @@
 (require racket/contract
          racket/list
          racket/match
+         racket/random
          racket/set
          racket/string)
 (require web-server/servlet


@@ 9,9 10,10 @@
          json)
 (require simple-http)
 (require readline/readline)
+(require (only-in openssl/sha1 bytes->hex-string))
 
 (define state  'registering)
-(define _peers   (mutable-set))
+(define _peers   (make-hasheq))
 (define _commits (make-hash))
 (define _outputs (make-hash))
 (define _sums    (make-hash))


@@ 70,11 72,15 @@
                [password (hash-ref params 'password)]
                [input (hash-ref params 'input)])
           (if (auth username password)
-              (begin
+              (let* ([token (crypto-random-bytes 128)]
+                     [token (bytes->hex-string token)])
                 (displayln (format "~a is voting! (~a)" username input))
-                (set-add! _peers (hasheq 'input input
-                                         'username username))
-                (response/jsexpr empty))
+                (hash-set! _peers (string->symbol token)
+                           (hasheq 'input input
+                                   'username username))
+                ; send the token that the peer will use for further
+                ; authorization
+                (response/jsexpr token))
               (response/jsexpr
                "Bad Login"
                #:code 400)))


@@ 85,23 91,25 @@
 
   (define (peer-count request)
     (if (eq? state 'committing)
-        (response/jsexpr (set-count _peers))
+        (response/jsexpr (hash-count _peers))
         (response/jsexpr
          "Committing has not begun"
          #:code 403)))
 
   (define (commit request)
     (if (eq? state 'committing)
-        (let ([params (bytes->jsexpr (request-post-data/raw request))])
+        (let* ([params (bytes->jsexpr (request-post-data/raw request))]
+               [peer   (hash-ref _peers (string->symbol
+                                         (hash-ref params 'token)))])
           (displayln params)
-          (hash-set! _commits (hash-ref params 'input)
+          (hash-set! _commits (hash-ref peer 'input)
                      (hasheq 'p (hash-ref params 'p))
                      ; TODO: D polynomial
                      ;; (hasheq 'd (hash-ref params 'd))
                      )
           ; has everyone committed?
           (when (eqv? (hash-count _commits)
-                      (set-count _peers))
+                      (hash-count _peers))
             (transition))
           (response/jsexpr empty))
         (response/jsexpr "Not in the committing phase"


@@ 109,7 117,7 @@
 
   (define (peers request)
     (if (eq? state 'voting)
-        (response/jsexpr (for/list ([v _peers])
+        (response/jsexpr (for/list ([v (hash-values _peers)])
                            (hash-ref v 'input)))
         (response/jsexpr
          "Voting has not begun"


@@ 117,17 125,19 @@
 
   (define (outputs request)
     (if (eq? state 'voting)
-        (begin
+        (let* ([params (bytes->jsexpr (request-post-data/raw request))]
+               ; ensure this is a registered peer
+               [peer   (hash-ref _peers (string->symbol
+                                         (hash-ref params 'token)))])
           ; TODO: check validity of inputs
-          (let ([params (bytes->jsexpr (request-post-data/raw request))])
-            (for ([(p v) params])
-              (hash-update! _outputs
-                            (symbol->string p)
-                            (λ (l) (cons v l)) empty)))
+          (for ([(p v) (hash-ref params 'outputs)])
+            (hash-update! _outputs
+                          (symbol->string p)
+                          (λ (l) (cons v l)) empty))
           ; has everyone submitted their outputs?
           (when (for/and ([(p v) _outputs])
                   (eqv? (length v)
-                        (set-count _peers)))
+                        (hash-count _peers)))
             (transition))
           (response/jsexpr empty))
         (response/jsexpr


@@ 136,9 146,11 @@
 
   (define (_values request)
     (if (eq? state 'summing)
-        (let ([input (hash-ref (bytes->jsexpr (request-post-data/raw request)) 'input)])
+        (let* ([params (bytes->jsexpr (request-post-data/raw request))]
+               [peer   (hash-ref _peers (string->symbol
+                                         (hash-ref params 'token)))])
           (response/jsexpr
-           (hash-ref _outputs input)))
+           (hash-ref _outputs (hash-ref peer 'input))))
         (response/jsexpr
          "This election is not in the summing phase"
          #:code 403)))


@@ 146,8 158,10 @@
   (define (sum request)
     (if (eq? state 'summing)
         (let* ([params (bytes->jsexpr (request-post-data/raw request))]
-               [input (string->symbol (hash-ref params 'input))]
-               [sum (hash-ref params 'sum)])
+               [peer   (hash-ref _peers (string->symbol
+                                         (hash-ref params 'token)))]
+               [input  (string->symbol (hash-ref peer 'input))]
+               [sum    (hash-ref params 'sum)])
           (hash-set! _sums input sum)
           (response/jsexpr
            empty))


@@ 157,7 171,7 @@
 
   (define (sums request)
     (if (eq? (length (hash-keys _sums))
-             (set-count _peers))
+             (hash-count _peers))
         (response/jsexpr
          _sums)
         (response/jsexpr


@@ 217,7 231,7 @@
                        ['cands
                         (displayln (hash-ref election->candidates election))]
                        ['peers
-                        (displayln _peers)])]
+                        (displayln (hash-values _peers))])]
               ['set (match (read sp)
                       ['election (let ([election (read sp)])
                                    (election-set! election))]

@@ 66,20 66,21 @@
   (define bulletin
     (update-port (update-host json-requester "localhost") 1984))
 
-  (void
-   (let ([username (readline "Username: ")]
-         [password (get-pass "Password: ")])
-     (with-handlers ([exn:fail:network:http:error?
-                      (λ ([ex : exn:fail:network:http:error])
-                        (newline)
-                        (displayln (format "Login refused: ~a"
-                                           (exn-message ex)))
-                        (exit))])
-       (post bulletin "/register"
-             #:data
-             (jsexpr->string (hasheq 'input (integer->hex-string point)
-                                     'username username
-                                     'password password))))))
+  (define token
+    (let ([username (readline "Username: ")]
+          [password (get-pass "Password: ")])
+      (with-handlers ([exn:fail:network:http:error?
+                       (λ ([ex : exn:fail:network:http:error])
+                         (newline)
+                         (displayln (format "Login refused: ~a"
+                                            (exn-message ex)))
+                         (exit))])
+        (json-response-body
+         (post bulletin "/register"
+               #:data
+               (jsexpr->string (hasheq 'input (integer->hex-string point)
+                                       'username username
+                                       'password password)))))))
 
   (displayln "retrieving candidates...")
   (define candidates (cast (json-response-body


@@ 155,8 156,7 @@
          #:data
          (jsexpr->string
           (hasheq
-           'input
-           (integer->hex-string point)
+           'token token
            'p
            (bytes->hex-string
             (merkle-node-hsh


@@ 177,10 177,13 @@
    (post bulletin "/outputs"
          #:data
          (jsexpr->string
-          (for/hasheq : (Immutable-HashTable Symbol String)
-              ([p : Integer (cast peer-inputs (Listof Integer))])
-            (values (string->symbol (integer->hex-string p))
-                    (integer->hex-string (poly p)))))))
+          (hasheq
+           'token token
+           'outputs
+           (for/hasheq : (Immutable-HashTable Symbol String)
+               ([p : Integer (cast peer-inputs (Listof Integer))])
+             (values (string->symbol (integer->hex-string p))
+                     (integer->hex-string (poly p))))))))
 
   (display "summing...")
   (void


@@ 188,8 191,7 @@
          #:data
          (jsexpr->string
           (hasheq
-           'input
-           (integer->hex-string point)
+           'token token
            'sum
            (integer->hex-string
             (foldl + 0


@@ 200,8 202,7 @@
                             (post bulletin "/values"
                                   #:data
                                   (jsexpr->string
-                                   (hasheq 'input
-                                           (integer->hex-string point))))))
+                                   (hasheq 'token token)))))
                           (Listof String)))))))))
   (newline)