EdDSA now supports multiple hashes as defined in curve_data.py. We still dont have sha512 though.

src/gen_headers/curve_data.py

@@ -35,8 +35,9 @@ curve_data = {
         "wnaf":wnaf_config(5,3),
         "window_bits":4,
         
-        "eddsa_hash": "sha512",
-        "eddsa_supports_contexts": 0
+        "eddsa_hash": "sha3_512", # TODO: no, actually it's SHA2-512
+        "eddsa_supports_contexts": 0,
+        "eddsa_dom": ""
     },
     "ed448goldilocks" : {
         "name" : "Ed448-Goldilocks",
@@ -49,7 +50,9 @@ curve_data = {
         
         "combs":comb_config(5,5,18),
         "wnaf":wnaf_config(5,3),
-        "window_bits":5
+        "window_bits":5,
+        
+        "eddsa_dom":"SigEd448"
     }
 }
 
@@ -106,7 +109,7 @@ for curve,data in curve_data.iteritems():
         data["iso_to"] = data["name"]
         
     if "eddsa_hash" not in data:
-        data["edddsa"] = "sha512"
+        data["eddsa_hash"] = "shake256"
         
     if "eddsa_supports_contexts" not in data:
         data["eddsa_supports_contexts"] = 1

src/per_curve/eddsa.tmpl.c

@@ -11,12 +11,12 @@
 #define API_NAME "$(c_ns)"
 #define API_NS(_id) $(c_ns)_##_id
 
-#define hash_ctx_t shake256_ctx_t
-#define hash_init shake256_init
-#define hash_update shake256_update
-#define hash_final shake256_final
-#define hash_destroy shake256_destroy
-#define hash_hash shake256_hash
+#define hash_ctx_t   $(eddsa_hash)_ctx_t
+#define hash_init    $(eddsa_hash)_init
+#define hash_update  $(eddsa_hash)_update
+#define hash_final   $(eddsa_hash)_final
+#define hash_destroy $(eddsa_hash)_destroy
+#define hash_hash    $(eddsa_hash)_hash
 
 #define SUPPORTS_CONTEXTS $(C_NS)_EDDSA_SUPPORTS_CONTEXTS
 
@@ -37,13 +37,21 @@ static void hash_init_with_dom(
     const uint8_t *context,
     uint8_t context_len
 ) {
-    const char *domS = "SigEd448";
-    const uint8_t dom[2] = {1+word_is_zero(prehashed), context_len};
-    
     hash_init(hash);
+    
+#if SUPPORTS_CONTEXTS
+    const char *domS = "$(eddsa_dom)";
+    const uint8_t dom[2] = {1+word_is_zero(prehashed), context_len};
     hash_update(hash,(const unsigned char *)domS, strlen(domS));
     hash_update(hash,dom,2);
     hash_update(hash,context,context_len);
+#else
+    (void)prehashed;
+    (void)context;
+    assert(context==NULL);
+    (void)context_len;
+    assert(context_len == 0);
+#endif
 }
 
 void API_NS(eddsa_derive_public_key) (

test/test_decaf.cxx

@@ -564,8 +564,6 @@ static void run() {
     printf("\n");
 }
 
-
-
 }; /* template<GroupId GROUP> struct Tests */
 
 /* X25519, X448 test vectors */