[Ceres] Allow arbitrary sized message in Crypto.verify_sig (#481)

* Allow arbitrary sized msg in signature verification

* Move Address.to_bytes documentation to correct place

CHANGELOG.md

@@ -24,6 +24,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   sized byte arrays.
 - `Chain.network_id` - a function to get hold of the Chain's network id.
 ### Changed
+- `Crypto.verify_sig` is changed to have `msg : bytes()`. I.e. the
+  signed data can be of any length (used to be limited to `bytes(32)`/`hash`).
 ### Removed
 - `Bitwise.aes` standard library is removed - the builtin operations are superior.
 

docs/sophia_stdlib.md

@@ -57,6 +57,12 @@ Address.to_str(a : address) : string
 
 Base58 encoded string
 
+#### to_bytes
+```
+Address.to_bytes(a : address) : bytes(32)
+```
+
+The binary representation of the address.
 
 #### is_contract
 ```
@@ -564,14 +570,6 @@ Chain.block_height : int"
 
 The height of the current block (i.e. the block in which the current call will be included).
 
-#### to_bytes
-```
-Address.to_bytes(a : address) : bytes(32)
-```
-
-The binary representation of the address.
-
-
 ##### bytecode_hash
 ```
 Chain.bytecode_hash : 'c => option(hash)
@@ -834,11 +832,14 @@ Hash any object to blake2b
 
 #### verify_sig
 ```
-Crypto.verify_sig(msg : hash, pubkey : address, sig : signature) : bool
+Crypto.verify_sig(msg : bytes(), pubkey : address, sig : signature) : bool
 ```
 
 Checks if the signature of `msg` was made using private key corresponding to
-the `pubkey`
+the `pubkey`.
+
+Note: before v8 of the compiler, `msg` had type `hash` (i.e. `bytes(32)`).
+
 
 #### ecverify_secp256k1
 ```

src/aeso_ast_infer_types.erl

@@ -775,7 +775,7 @@ global_env() ->
     %% Crypto/Curve operations
     CryptoScope = #scope
         { funs = MkDefs(
-                     [{"verify_sig",           Fun([Hash, Address, SignId], Bool)},
+                     [{"verify_sig",           Fun([Bytes('_'), Address, SignId], Bool)},
                       {"verify_sig_secp256k1", Fun([Hash, Bytes(64), SignId], Bool)},
                       {"ecverify_secp256k1",   Fun([Hash, Bytes(20), Bytes(65)], Bool)},
                       {"ecrecover_secp256k1",  Fun([Hash, Bytes(65)], Option(Bytes(20)))},

test/contracts/unapplied_builtins.aes

@@ -36,7 +36,7 @@ contract UnappliedBuiltins =
   function map_delete()                  = Map.delete : (_, m) => _
   function map_from_list()               = Map.from_list : _ => m
   function map_to_list()                 = Map.to_list : m => _
-  function crypto_verify_sig()           = Crypto.verify_sig
+  function crypto_verify_sig()           = Crypto.verify_sig : (bytes(), _, _) => _
   function crypto_verify_sig_secp256k1() = Crypto.verify_sig_secp256k1
   function crypto_ecverify_secp256k1()   = Crypto.ecverify_secp256k1
   function crypto_ecrecover_secp256k1()  = Crypto.ecrecover_secp256k1