[Ed25519] Wrap the return value of Ed25519.sign and .verify with Right

scheme-libs/racket/unison/crypto.rkt

@@ -3,6 +3,7 @@
          ffi/unsafe/define
          racket/exn
          racket/runtime-path
+         (only-in unison/data-info ref-either-left ref-either-right)
          (for-syntax racket/base)
          openssl/libcrypto
          unison/chunked-seq
@@ -23,10 +24,12 @@
         HashAlgorithm.Blake2b_256
         HashAlgorithm.Blake2b_512
         hashBytes
-        hmacBytes
-        Ed25519.sign.impl
-        Ed25519.verify.impl
-        )))
+        hmacBytes))
+    (prefix-out builtin-crypto.
+        (combine-out
+            Ed25519.sign.impl
+            Ed25519.verify.impl))
+        )
 
 (define-runtime-path libb2-so '(so "libb2" ("1" #f)))
 
@@ -50,6 +53,14 @@
   (unless (= 1 v)
     (error who "failed with return value ~a" v)))
 
+(define ERR_get_error (if (string? libcrypto)
+        (lambda _ (raise (error 'libcrypto "ERR_get_error\n~a" libcrypto)))
+        (get-ffi-obj "ERR_get_error" libcrypto (_fun -> _long))))
+(define ERR_error_string_n (if (string? libcrypto)
+        (lambda _ (raise (error 'libcrypto "ERR_error_string_n\n~a" libcrypto)))
+        (get-ffi-obj "ERR_error_string_n" libcrypto
+            (_fun _long _bytes _long -> _void))))
+
 (define EVP_Digest
     (if (string? libcrypto)
         (lambda _ (raise (error 'libcrypto "EVP_Digest\n~a" libcrypto)))
@@ -200,39 +211,46 @@
             -> _int
             ))))
 
+(define (get-error-message id)
+  (let* ([buffer (make-bytes 512)])
+    (ERR_error_string_n id buffer (bytes-length buffer))
+    (bytes->string/utf-8 buffer)))
+
+(define (libcrypto-error message)
+    (error (string-append message (get-error-message (ERR_get_error)))))
 
 (define EVP_PKEY_ED25519 1087)
 (define (evpSign-raw seed input)
   (let* ([ctx (EVP_MD_CTX_new)]
          [pkey (EVP_PKEY_new_raw_private_key EVP_PKEY_ED25519 #f seed (bytes-length seed))])
     (if (false? pkey)
-      (raise (error "Invalid seed provided."))
+      (raise (libcrypto-error "Invalid seed provided. "))
       (if (<= (EVP_DigestSignInit ctx #f #f #f pkey) 0)
-        (raise (error "Initializing signing failed"))
+        (raise (libcrypto-error "Initializing signing failed. "))
         (let* ([output (make-bytes 64)])
           (if (<= (EVP_DigestSign ctx output input (bytes-length input)) 0)
-            (raise (error "Running digest failed"))
+            (raise (libcrypto-error "Running digest failed. "))
             output))))))
 
 (define (evpVerify-raw public-key input signature)
   (let* ([ctx (EVP_MD_CTX_new)]
          [pkey (EVP_PKEY_new_raw_public_key EVP_PKEY_ED25519 #f public-key (bytes-length public-key))])
     (if (false? pkey)
-      (raise (error "Invalid seed provided."))
+      (raise (libcrypto-error "Invalid seed provided. "))
       (if (<= (EVP_DigestVerifyInit ctx #f #f #f pkey) 0)
-        (raise (error "Initializing Verify failed"))
+        (raise (libcrypto-error "Initializing Verify failed. "))
         (if (<= (EVP_DigestVerify ctx signature (bytes-length signature) input (bytes-length input)) 0)
           #f
           #t)))))
 
 (define (Ed25519.sign.impl seed _ignored_pubkey input)
-    (bytes->chunked-bytes (evpSign-raw (chunked-bytes->bytes seed) (chunked-bytes->bytes input))))
+    (ref-either-right (bytes->chunked-bytes (evpSign-raw (chunked-bytes->bytes seed) (chunked-bytes->bytes input)))))
 
 (define (Ed25519.verify.impl public-key input signature)
-    (evpVerify-raw
+    (ref-either-right (evpVerify-raw
         (chunked-bytes->bytes public-key)
         (chunked-bytes->bytes input)
-        (chunked-bytes->bytes signature)))
+        (chunked-bytes->bytes signature))))
 
 ; This one isn't provided by libcrypto, for some reason
 (define (HashAlgorithm.Blake2b_256) (cons 'blake2b 256))

scheme-libs/racket/unison/primops.ss

@@ -547,6 +547,8 @@
     unison-FOp-crypto.HashAlgorithm.Blake2s_256
     unison-FOp-crypto.HashAlgorithm.Blake2b_256
     unison-FOp-crypto.HashAlgorithm.Blake2b_512
+    builtin-crypto.Ed25519.sign.impl
+    builtin-crypto.Ed25519.verify.impl
 
     unison-FOp-IO.clientSocket.impl.v3
     unison-FOp-IO.closeSocket.impl.v3
@@ -1388,7 +1390,7 @@
             (exception->string e)
             ref-unit-unit))])
       (thunk ref-unit-unit)))
-  
+
   (declare-builtin-link builtin-Float.*)
   (declare-builtin-link builtin-Float.fromRepresentation)
   (declare-builtin-link builtin-Float.toRepresentation)