rvv040 - decodeSaplingAddress Function added

SaplingAddress  data type added

CHANGELOG.md

@@ -5,6 +5,21 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.5.5.1]
+
+### Added
+
+- Added unction to decode a Sappling Address in Human Readable Format
+  `decodeSaplingAddress` returns 43 byte array containing
+- Added a new Datatype `SaplingAddress` 
+- Added a new FFI function `rust_wrapper_decode_sapling_address` to haskell-rust interface
+
+### Changed
+
+- `TransparentAddress` type refactored
+- `TransparentReceiver` added to replace old `TransparentAddress` 
+- `sha256` Function moved outside of `encodeTransparentReceiver`
+
 ## [0.5.5.0]
 
 ### Added
@@ -16,7 +31,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `TransparentAddress` type refactored
 - `TransparentReceiver` added to replace old `TransparentAddress` 
 - `sha256` Function moved outside of `encodeTransparentReceiver`
-
 ## [0.5.4.1]
 
 ### Added

librustzcash-wrapper/src/lib.rs

@@ -90,6 +90,7 @@ use zcash_address::{
     ZcashAddress
 };
 
+use zcash_client_backend::encoding::decode_payment_address;
 use zcash_client_backend::keys::sapling::{
     spending_key,
     ExtendedFullViewingKey,
@@ -1242,3 +1243,50 @@ pub extern "C" fn rust_wrapper_read_sapling_position(
         }
     }
 }
+
+#[no_mangle]
+pub extern "C" fn rust_wrapper_decode_sapling_address(
+    sapling: *const u8,
+    sapling_len: usize,
+    out: *mut u8,
+    out_len: &mut usize){
+    let sapling_address_from_haskell : Vec<u8> = marshall_from_haskell_var(sapling, sapling_len, RW);
+    let sapling_address = std::str::from_utf8(&sapling_address_from_haskell).unwrap();
+
+    let mut netid = 0;
+    match sapling_address.find("1") {
+        Some(ix) => {
+                let netstr = &sapling_address[0..ix];
+                if  netstr == "zs" {
+                    netid = 1
+                } else {
+                    if netstr == "ztestsapling" {
+                        netid = 2
+                    }    
+                } 
+            match decode_payment_address(netstr, sapling_address) {
+                Ok( t )=> {
+                    let address_to_bytes = t.to_bytes();
+                    let mut out_bytes_temp : [u8;44] = [0;44];
+                    out_bytes_temp[0] = netid;
+                    let mut iy = 1;
+                    for ix in 0..43 {
+                        out_bytes_temp[iy] = address_to_bytes[ix];
+                        iy += 1;
+                    } 
+                    let out_bytes: Vec<u8> = out_bytes_temp.to_vec();
+                    marshall_to_haskell_var(&out_bytes, out, out_len, RW);
+                }
+                Err(e) => {
+                    let h = vec![0];
+                    marshall_to_haskell_var(&h, out, out_len, RW);
+                }
+            }
+        }
+        None => {
+            let h = vec![0];
+            marshall_to_haskell_var(&h, out, out_len, RW);
+        }
+    } 
+} 
+

src/C/Zcash.chs

@@ -232,3 +232,10 @@ import ZcashHaskell.Types
   -> `()'
 #}
 
+{# fun unsafe rust_wrapper_decode_sapling_address as rustWrapperDecodeSaplingAddress
+     { toBorshVar* `BS.ByteString'&
+     , getVarBuffer `Buffer (BS.ByteString)'&
+     }
+  -> `()'
+#}
+

src/ZcashHaskell/Sapling.hs

@@ -22,6 +22,7 @@ import C.Zcash
   , rustWrapperReadSaplingCommitmentTree
   , rustWrapperReadSaplingPosition
   , rustWrapperReadSaplingWitness
+  , rustWrapperDecodeSaplingAddress
   , rustWrapperSaplingCheck
   , rustWrapperSaplingChgPaymentAddress
   , rustWrapperSaplingDecodeEsk
@@ -45,6 +46,7 @@ import ZcashHaskell.Types
   , DecodedNote(..)
   , RawData(..)
   , RawTxResponse(..)
+  , SaplingAddress(..)
   , SaplingCommitmentTree(..)
   , SaplingReceiver(..)
   , SaplingSpendingKey(..)
@@ -205,3 +207,26 @@ getSaplingWitness tree =
 getSaplingNotePosition :: SaplingWitness -> Integer
 getSaplingNotePosition =
   fromIntegral . rustWrapperReadSaplingPosition . hexBytes . sapWit
+
+getNetId:: [Word8] -> ZcashNet
+getNetId [x] = do 
+  case x of 
+    1 -> MainNet
+    2 -> TestNet 
+
+
+-- | decode a Sapling address 
+decodeSaplingAddress :: BS.ByteString -> Maybe SaplingAddress
+decodeSaplingAddress sapling_address = do 
+  if BS.length sa > 1
+    then do
+      let sa0 = BS.unpack sa
+      Just $ SaplingAddress  (getNetId (take 1 sa0)) (BS.pack (drop 1 sa0))
+    else Nothing
+  where 
+    sa = 
+      withPureBorshVarBuffer $
+      rustWrapperDecodeSaplingAddress sapling_address
+
+
+  

src/ZcashHaskell/Types.hs

@@ -477,6 +477,12 @@ newtype SaplingReceiver =
 instance ToBytes SaplingReceiver where
   getBytes (SaplingReceiver s) = s
 
+data SaplingAddress = SaplingAddress 
+  {
+    net_type :: !ZcashNet
+  , address :: !BS.ByteString  
+  } deriving (Eq, Prelude.Show, Read)
+  
 -- | Type to represent a Sapling Shielded Spend as provided by the @getrawtransaction@ RPC method
 data ShieldedSpend = ShieldedSpend
   { sp_cv :: !HexString

test/Spec.hs

@@ -57,6 +57,7 @@ import ZcashHaskell.Sapling
   , isValidShieldedAddress
   , matchSaplingAddress
   , updateSaplingCommitmentTree
+  , decodeSaplingAddress
   )
 import ZcashHaskell.Transparent
 import ZcashHaskell.Types
@@ -94,6 +95,7 @@ import ZcashHaskell.Types
   , fromRawSBundle
   , fromRawTBundle
   , getValue
+  , SaplingAddress(..)
   )
 import ZcashHaskell.Utils
 
@@ -911,6 +913,17 @@ main = do
                     t_rec u
               (ta_receiver <$> decodeTransparentAddress (E.encodeUtf8 tAdd)) `shouldBe`
                 t_rec u
+      describe "Decode a Sapling Address (MainNet)" $ do
+        let sa = decodeSaplingAddress "zs1waxrpde36rlrjdwfhnvw030sn29lzwmvmeupd8x2uuqgypaafx7mqcy0ep8yf2xtg30n5424t60"
+        it "Try to decode a valid MainNet Sapling Address" $ do
+          print sa
+          sa `shouldNotBe` Nothing
+      describe "Decode a Sapling Address (TestNet)" $ do
+        let sa = decodeSaplingAddress "ztestsapling188csdsvhdny25am8ume03qr2026hdy03zpg5pq7jmmfxtxtct0e93p0rg80yfxvynqd4gwlwft5"
+        it "Try to decode a valid TestNet Sapling Address " $ do
+          print sa
+          sa `shouldBe` Nothing
+
 
 -- | Properties
 prop_PhraseLength :: Property