segwit transaction addresses now leaving out witnesses

RooSoft · Nov 13, 2022 · 706af33 · 706af33
1 parent 4d181cf
commit 706af33
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Showing 6 changed files with 161 additions and 41 deletions.
diff --git a/lib/key/private_key.ex b/lib/key/private_key.ex
@@ -231,7 +231,7 @@ defmodule BitcoinLib.Key.PrivateKey do
   """
   @spec from_derivation_path(%PrivateKey{}, %DerivationPath{}) :: {:ok, %PrivateKey{}}
   def from_derivation_path(%PrivateKey{} = private_key, %DerivationPath{} = derivation_path) do
-    with {:ok, private_key} = ChildFromDerivationPath.get(private_key, derivation_path) do
+    with {:ok, private_key} <- ChildFromDerivationPath.get(private_key, derivation_path) do
       {:ok, add_fingerprint(private_key)}
     else
       {:error, message} -> {:error, message}

diff --git a/lib/signing/psbt/global/unsigned_tx.ex b/lib/signing/psbt/global/unsigned_tx.ex
@@ -6,6 +6,7 @@ defmodule BitcoinLib.Signing.Psbt.Global.UnsignedTx do
     keypair
     |> validate_keypair()
     |> decode_transaction()
+    |> validate_witness()
   end
 
   defp validate_keypair(keypair) do
@@ -34,4 +35,11 @@ defmodule BitcoinLib.Signing.Psbt.Global.UnsignedTx do
         end
     end
   end
+
+  defp validate_witness({:error, message}), do: {:error, message}
+
+  defp validate_witness({:ok, %Transaction{segwit?: true, witness: []}}),
+    do: {:error, "unsigned tx serialized with witness serialization format"}
+
+  defp validate_witness({:ok, transaction}), do: {:ok, transaction}
 end
diff --git a/lib/transaction.ex b/lib/transaction.ex
@@ -2,7 +2,7 @@ defmodule BitcoinLib.Transaction do
   @moduledoc """
   Based on https://learnmeabitcoin.com/technical/transaction-data#fields
   """
-  defstruct [:version, :id, :inputs, :outputs, :locktime, witness: []]
+  defstruct [:version, :id, :inputs, :outputs, :locktime, :segwit?, witness: []]
 
   alias BitcoinLib.Crypto
   alias BitcoinLib.Key.PrivateKey
@@ -40,7 +40,8 @@ defmodule BitcoinLib.Transaction do
               ]
             }
           ],
-          locktime: 0
+          locktime: 0,
+          segwit?: false
         }
       }
   """
@@ -82,14 +83,18 @@ defmodule BitcoinLib.Transaction do
               ]
             }
           ],
-          locktime: 0
+          locktime: 0,
+          segwit?: false
         }
       }
   """
   @spec decode(bitstring()) :: {:ok, %Transaction{}} | {:error, binary()}
   def decode(encoded_transaction) do
-    encoded_transaction
-    |> Decoder.to_struct()
+    with {:ok, transaction} <- Decoder.to_struct(encoded_transaction) do
+      {:ok, add_id(transaction)}
+    else
+      {:error, message} -> {:error, message}
+    end
   end
 
   @doc """
@@ -186,31 +191,102 @@ defmodule BitcoinLib.Transaction do
   """
   @spec add_id(%Transaction{}) :: %Transaction{}
   def add_id(%Transaction{} = transaction) do
-    id =
-      transaction
-      |> encode()
-      |> id_from_encoded_transaction()
+    Map.put(transaction, :id, to_id(transaction))
+  end
+
+  @doc """
+  Hashes the transaction's id
 
+  ## Examples
+      iex> %BitcoinLib.Transaction{
+      ...>   version: 2,
+      ...>   inputs: [
+      ...>     %BitcoinLib.Transaction.Input{
+      ...>       txid: "5a957f4bff6d23140eb7e9b6fcedd41d3febf1e145d37519c593c939789a49af",
+      ...>       vout: 0,
+      ...>       script_sig: [],
+      ...>       sequence: 4294967293
+      ...>     }
+      ...>   ],
+      ...>   outputs: [
+      ...>     %BitcoinLib.Transaction.Output{
+      ...>       value: 1303734,
+      ...>       script_pub_key: [%BitcoinLib.Script.Opcodes.Stack.Dup{},
+      ...>        %BitcoinLib.Script.Opcodes.Crypto.Hash160{},
+      ...>        %BitcoinLib.Script.Opcodes.Data{value: <<0x05e17c02fb238ca0779b3533271ebe916b01bcab::160>>},
+      ...>        %BitcoinLib.Script.Opcodes.BitwiseLogic.EqualVerify{},
+      ...>        %BitcoinLib.Script.Opcodes.Crypto.CheckSig{script: <<0x76a91405e17c02fb238ca0779b3533271ebe916b01bcab88ac::200>>}]
+      ...>     }
+      ...>   ],
+      ...>   locktime: 2378041,
+      ...>   witness: []
+      ...> }
+      ...> |> BitcoinLib.Transaction.to_id()
+      "b62e9d36389427d39e5d438a05045c23d1938e4242661c5fe2ad87c46337b091"
+  """
+  @spec to_id(%Transaction{}) :: binary()
+  def to_id(%Transaction{} = transaction) do
     transaction
-    |> Map.put(:id, id)
+    |> Encoder.for_txid()
+    |> Crypto.double_sha256()
+    |> Crypto.Bitstring.reverse()
+    |> Binary.to_hex()
   end
 
   @doc """
   Computes a transaction id from an encoded transaction in bitstring format
 
   ## Examples
-      Based on https://bitcoin.stackexchange.com/a/2233/101041
+      A random transaction
+
+      iex> "010000000001016dc77969a38fcd7ade1524658b7cf04430eefcbed5ed18e8907f938932ee6b360100000000f5ffffff02404b4c000000000017a9140403fb8f4a93093430e338f346efe40774b45f95873c75360000000000160014a79e4076fca80a3742536d1d5cd364d5cfe0eeaf02483045022100ff621967f1a0c231dbdaf500a83079d4a5c32e64e2d6b3809ff47ee25c7750ca0220326d95db84811e391af38aded348c8f26cdf793be3ed19ae1185cc03aef42fa8012102b57b7b110b4c00ae0f2ed1594174ebcc2f4077667867ba2cb514bbf59ae8868500000000"
+      ...> |> Binary.from_hex()
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "651560f701575fb0b15780b6ba771bf6096b1d6b6c6202b3d79915ebbac5ebff"}
+
+      The transaction in the genesis block
+
+      iex> "01000000010000000000000000000000000000000000000000000000000000000000000000FFFFFFFF4D04FFFF001D0104455468652054696D65732030332F4A616E2F32303039204368616E63656C6C6F72206F6E206272696E6B206F66207365636F6E64206261696C6F757420666F722062616E6B73FFFFFFFF0100F2052A01000000434104678AFDB0FE5548271967F1A67130B7105CD6A828E03909A67962E0EA1F61DEB649F6BC3F4CEF38C4F35504E51EC112DE5C384DF7BA0B8D578A4C702B6BF11D5FAC00000000"
+      ...> |> Binary.from_hex()
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b"}
+
+      From real world ElectrumClient example
+
+      iex> "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"
+      ...> |> Binary.from_hex()
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "f318dd60cc36fb1238e39abf697b471881ed811f2f66b0bdeed15e29d3032c76"}
+
+      From https://learnmeabitcoin.com/technical/txid
+
+      iex> "01000000000101c6548bbe4e6a1bc65c2b6546b15c5bcb17682d0418d866632ec5328f0e6c46420000000000ffffffff02dcc5630000000000160014349a727852238d54d2d98662b72ba19d48dafea1c01d13000000000017a9140efd4916baef33b979989542f21a4e182a992bf6870247304402207b6a1d52a7bcfc87b776f3946a5c57fc686828131f87603f0e87b9c5cddfe4d90220405070bac780bf313df38c174313a48437e67eedf3234ef0770760d005f9182e012102b173048a5b94939f9486826d41b87add8a20910f7ff8acadabb5f89edbd0da9b00000000"
+      ...> |> Binary.from_hex()
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "c7fbe3f35f6060555279ba455c1c4d419ceaaa1a5fe68940913a431296d37f5b"}
+
+      iex> <<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::2200>>
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16"}
+
+      iex> "02000000000101fabb6b29687f2047622f546cc97aedce4407da5d96b7f7d72e53c7fdbae9b5930100000000fdffffff02e63be7390000000017a9140e825b4005779df0808738f3beabcee7abe5b46687436b1200000000001976a9146b426bed96ace2804e99f29304a9eb1b1260ea6688ac0247304402207e39cfe660bc35ab24229a820d847aa97b3dfd96623cc5b6cc679d11215d2b3402201a7a2ddda43b8698968e38fc44a967a86d0e088103b24695e79c091c6139754b012103ee237db683c637ddf2bd51bc39555084dcc402599625bb1a2ec02fd2a1a79ddeaba40b00"
+      ...> |> Binary.from_hex()
+      ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
+      {:ok, "6991e107b306fa1629f3b41054ec856dbcc379aac28cc8c84102163d03239f88"}
+
+      Another one based on https://bitcoin.stackexchange.com/a/2233/101041
 
       iex> <<0x01000000010000000000000000000000000000000000000000000000000000000000000000FFFFFFFF4D04FFFF001D0104455468652054696D65732030332F4A616E2F32303039204368616E63656C6C6F72206F6E206272696E6B206F66207365636F6E64206261696C6F757420666F722062616E6B73FFFFFFFF0100F2052A01000000434104678AFDB0FE5548271967F1A67130B7105CD6A828E03909A67962E0EA1F61DEB649F6BC3F4CEF38C4F35504E51EC112DE5C384DF7BA0B8D578A4C702B6BF11D5FAC00000000::1632>>
       ...> |> BitcoinLib.Transaction.id_from_encoded_transaction()
-      "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b"
+      {:ok, "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b"}
   """
   @spec id_from_encoded_transaction(bitstring()) :: binary()
   def id_from_encoded_transaction(encoded_transaction) do
-    encoded_transaction
-    |> Crypto.double_sha256()
-    |> Crypto.Bitstring.reverse()
-    |> Binary.to_hex()
+    with {:ok, transaction} <- Decoder.to_struct(encoded_transaction) do
+      {:ok, to_id(transaction)}
+    else
+      {:error, message} -> {:error, message}
+    end
   end
 
   @doc """

diff --git a/lib/transaction/decoder.ex b/lib/transaction/decoder.ex
@@ -21,7 +21,6 @@ defmodule BitcoinLib.Transaction.Decoder do
         :ok,
         %BitcoinLib.Transaction{
           version: 1,
-          id: "b1caa607a324ed9132c3d894d2cf7a22d59cdb4022bd8827c49e2f0d8ca018c6",
           inputs: [
             %BitcoinLib.Transaction.Input{
               txid: "3f4fa19803dec4d6a84fae3821da7ac7577080ef75451294e71f9b20e0ab1e7b",
@@ -42,24 +41,23 @@ defmodule BitcoinLib.Transaction.Decoder do
               ]
             }
           ],
-          locktime: 1170
+          locktime: 1170,
+          segwit?: false
         }
       }
   """
   @spec to_struct(bitstring()) :: {:ok, %Transaction{}} | {:error, binary()}
   def to_struct(encoded_transaction) do
     # see https://github.com/bitcoin/bips/blob/master/bip-0144.mediawiki#hashes
-    Transaction.id_from_encoded_transaction(encoded_transaction)
-    |> version_specific_extract(encoded_transaction)
+    version_specific_extract(encoded_transaction)
   end
 
   # Extracts a witness transaction
   defp version_specific_extract(
-         id,
          <<version::little-32, @marker::8, @flag::8, remaining::bitstring>>
        ) do
     result =
-      %{remaining: remaining, witness_signature?: true}
+      %{remaining: remaining}
       |> extract_input_count
       |> extract_inputs
       |> extract_output_count
@@ -75,20 +73,20 @@ defmodule BitcoinLib.Transaction.Decoder do
       %{inputs: inputs, outputs: outputs, witness: witness, locktime: locktime} ->
         {:ok,
          %Transaction{
-           id: id,
            version: version,
            inputs: inputs,
            outputs: outputs,
            witness: witness,
-           locktime: locktime
+           locktime: locktime,
+           segwit?: true
          }}
     end
   end
 
   # Extracts a non-witness transaction
-  defp version_specific_extract(id, remaining) do
+  defp version_specific_extract(remaining) do
     result =
-      %{remaining: remaining, witness_signature?: false}
+      %{remaining: remaining}
       |> extract_version
       |> extract_input_count
       |> extract_inputs
@@ -104,11 +102,11 @@ defmodule BitcoinLib.Transaction.Decoder do
       %{version: version, inputs: inputs, outputs: outputs, locktime: locktime} ->
         {:ok,
          %Transaction{
-           id: id,
            version: version,
            inputs: inputs,
            outputs: outputs,
-           locktime: locktime
+           locktime: locktime,
+           segwit?: false
          }}
     end
   end
@@ -149,20 +147,14 @@ defmodule BitcoinLib.Transaction.Decoder do
 
   defp extract_witness(%{error: message}), do: %{error: message}
 
-  defp extract_witness(%{remaining: remaining, witness_signature?: witness_signature?} = map) do
+  defp extract_witness(%{remaining: remaining} = map) do
     %CompactInteger{value: witness_count, remaining: remaining} =
       CompactInteger.extract_from(remaining, :big_endian)
 
-    case witness_count == 0 && witness_signature? do
-      true ->
-        %{error: "unsigned tx serialized with witness serialization format"}
+    {witness, remaining} = extract_witness_list([], remaining, witness_count)
 
-      false ->
-        {witness, remaining} = extract_witness_list([], remaining, witness_count)
-
-        %{map | remaining: remaining}
-        |> Map.put(:witness, witness)
-    end
+    %{map | remaining: remaining}
+    |> Map.put(:witness, witness)
   end
 
   defp extract_witness_list(witnesses, remaining, 0), do: {witnesses, remaining}

diff --git a/lib/transaction/encoder.ex b/lib/transaction/encoder.ex
@@ -16,7 +16,7 @@ defmodule BitcoinLib.Transaction.Encoder do
   Encodes a transaction in binary format from a structure
 
   ## Examples
-      iex> transaction = %BitcoinLib.Transaction{
+      iex> %BitcoinLib.Transaction{
       ...>   inputs: [
       ...>     %BitcoinLib.Transaction.Input{
       ...>       script_sig: nil,
@@ -40,7 +40,7 @@ defmodule BitcoinLib.Transaction.Encoder do
       ...>   locktime: 0,
       ...>   version: 1
       ...> }
-      ...> BitcoinLib.Transaction.Encoder.from_struct(transaction)
+      ...> |> BitcoinLib.Transaction.Encoder.from_struct()
       <<1, 0, 0, 0>> <> # version
       <<1>> <>          # input_count
       <<0x449d45bbbfe7fc93bbe649bb7b6106b248a15da5dbd6fdc9bdfc7efede83235e0100000000ffffffff::328>> <> # inputs
@@ -62,6 +62,49 @@ defmodule BitcoinLib.Transaction.Encoder do
     |> Map.get(:encoded)
   end
 
+  @doc """
+  Specific encoding meant to generate Transaction ID's
+
+  ## Examples
+
+      iex> %BitcoinLib.Transaction{
+      ...>   inputs: [
+      ...>     %BitcoinLib.Transaction.Input{
+      ...>       script_sig: nil,
+      ...>       sequence: 0xFFFFFFFF,
+      ...>       txid: "5e2383defe7efcbdc9fdd6dba55da148b206617bbb49e6bb93fce7bfbb459d44",
+      ...>       vout: 1
+      ...>     }
+      ...>   ],
+      ...>   outputs: [
+      ...>     %BitcoinLib.Transaction.Output{
+      ...>       script_pub_key: [
+      ...>         %BitcoinLib.Script.Opcodes.Stack.Dup{},
+      ...>         %BitcoinLib.Script.Opcodes.Crypto.Hash160{},
+      ...>         %BitcoinLib.Script.Opcodes.Data{value: <<0xf86f0bc0a2232970ccdf4569815db500f1268361::160>>},
+      ...>         %BitcoinLib.Script.Opcodes.BitwiseLogic.EqualVerify{},
+      ...>         %BitcoinLib.Script.Opcodes.Crypto.CheckSig{}
+      ...>       ],
+      ...>       value: 129000000
+      ...>     }
+      ...>   ],
+      ...>   locktime: 0,
+      ...>   version: 1
+      ...> }
+      ...> |> BitcoinLib.Transaction.Encoder.for_txid()
+      <<0x0100000001449d45bbbfe7fc93bbe649bb7b6106b248a15da5dbd6fdc9bdfc7efede83235e0100000000ffffffff014062b007000000001976a914f86f0bc0a2232970ccdf4569815db500f126836188ac00000000::680>>
+  """
+  def for_txid(%Transaction{} = transaction) do
+    %{transaction: transaction, encoded: <<>>}
+    |> append_version
+    |> append_input_count
+    |> append_inputs
+    |> append_output_count
+    |> append_outputs
+    |> append_locktime
+    |> Map.get(:encoded)
+  end
+
   defp append_version(%{transaction: %Transaction{version: version}, encoded: encoded} = map) do
     %{map | encoded: <<encoded::binary, version::little-32>>}
   end

diff --git a/test/integration/transactions/decode_raw_transaction_test.exs b/test/integration/transactions/decode_raw_transaction_test.exs
@@ -62,6 +62,7 @@ defmodule BitcoinLib.Test.Integration.Transactions.DecodeRawTransactionTest do
                }
              ],
              locktime: 0,
+             segwit?: false,
              witness: []
            }
   end
-Original file line number
+Diff line change
@@ Expand Up @@
                    }
                  ],
                  locktime: 0,
+                 segwit?: false,
                  witness: []
                }
       end
@@ Expand Down @@