New messaging specification (replacing old deposit/withdrawal spec)

specs/protocol/identifiers.md

@@ -4,8 +4,7 @@
 - [Contract ID](#contract-id)
 - [UTXO ID](#utxo-id)
   - [Coin ID](#coin-id)
-  - [Deposit ID](#deposit-id)
-    - [Deposit Asset ID](#deposit-asset-id)
+  - [Message ID](#message-id)
   - [Fee ID](#fee-id)
 
 This document defines how to compute unique identifiers.
@@ -24,14 +23,9 @@ For a transaction of type `TransactionType.Create`, `tx`, the contract ID is `sh
 
 Is represented as an _outpoint_: a pair of [transaction ID](#transaction-id) as `byte[32]` and output index as a `uint8`.
 
+### Message ID
 
-### Deposit ID
-
-The ID of a deposit is computed as the [hash](./cryptographic_primitives.md#hashing) of the [Deposit Asset ID](#deposit-asset-id) `byte[32]`, recipient address `byte[32]`, amount `uint64` and deposit nonce `uint64`: `hash(byte[32] ++ byte[32] ++ uint64 ++ uint64)`. All value types are serialized according to the standard [transaction serialization](./tx_format.md#transaction).
-
-#### Deposit Asset ID
-
-The ID of a deposit asset is computed as the [hash](./cryptographic_primitives.md#hashing) of the token address `byte[32]` and token precision `uint8`: `hash(byte[32] ++ uint8)`. The address value is serialized as a byte array of length 32 left-padded with zeroes, and all other value types are serialized according to the standard [transaction serialization](./tx_format.md#transaction).
+The ID of a message is computed as the [hash](./cryptographic_primitives.md#hashing) of the sender address `byte[32]`, recipient address `byte[32]`, the abi encoded message (either [EVM abi](https://docs.soliditylang.org/en/v0.8.13/abi-spec.html) or [FuelVM abi](./abi.md)) `byte[]`, the amount being sent with the message `uint64`, the message nonce `uint64` and the message owner (either address or predicate hash) `byte[32]`: `hash(byte[32] ++ byte[32] ++ byte[] ++ uint64 ++ uint64 ++ byte[32])`. The address values are serialized as a byte array of length 32 left-padded with zeroes, and all other value types are serialized according to the standard [transaction serialization](./tx_format.md#transaction). If the owner component is not applicable then a 32 byte long array of zeros should be used.
 
 ### Fee ID
 

specs/protocol/tx_format.md

@@ -8,12 +8,13 @@
 - [InputType](#inputtype)
 - [Input](#input)
   - [InputCoin](#inputcoin)
-  - [InputContract](#inputcontract)
+  - [fInputContract](#inputcontract)
+  - [InputMessage](#inputmessage)
 - [OutputType](#outputtype)
 - [Output](#output)
   - [OutputCoin](#outputcoin)
   - [OutputContract](#outputcontract)
-  - [OutputWithdrawal](#outputwithdrawal)
+  - [OutputMessage](#outputmessage)
   - [OutputChange](#outputchange)
   - [OutputVariable](#outputvariable)
   - [OutputContractCreated](#outputcontractcreated)
@@ -170,6 +171,7 @@ Creates a contract with contract ID as computed [here](./identifiers.md#contract
 enum  InputType : uint8 {
     Coin = 0,
     Contract = 1,
+    Message = 2
 }
 ```
 
@@ -178,7 +180,7 @@ enum  InputType : uint8 {
 | name   | type                                                              | description    |
 |--------|-------------------------------------------------------------------|----------------|
 | `type` | [InputType](#inputtype)                                           | Type of input. |
-| `data` | One of [InputCoin](#inputcoin) or [InputContract](#inputcontract) | Input data.    |
+| `data` | One of [InputCoin](#inputcoin), [InputContract](#inputcontract) or [InputMessage](#inputmessage) | Input data.    |
 
 Transaction is invalid if:
 
@@ -239,13 +241,39 @@ Note: when verifying a predicate, `txID`, `outputIndex`, `balanceRoot`, `stateRo
 
 Note: when executing a script, `txID`, `outputIndex`, `balanceRoot`, and `stateRoot` are initialized to the transaction ID, output index, amount, and state root of the contract with ID `contractID`, and `txPointer` is initialized to zero.
 
+### InputMessage
+
+| name                  | type        | description                                                            |
+|-----------------------|-------------|------------------------------------------------------------------------|
+| `messageID`           | `byte[32]`  | The messageID as described [here](./identifiers.md#message-id).        |
+| `sender`              | `byte[32]`  | The address of the message sender.                                     |
+| `recipient`           | `byte[32]`  | The address of the message recipient.                                  |
+| `callABI`             | `byte[]`    | The [abi encoded](./abi.md) call to execute.                           |
+| `amount`              | `uint64`    | Amount of base asset coins sent with message.                          |
+| `nonce`               | `uint64`    | The message nonce.                                                     |
+| `owner`               | `byte[32]`  | Owning address or predicate hash.                                      |
+| `witnessIndex`        | `uint8`     | Index of witness that authorizes spending the coin.                    |
+| `predicateLength`     | `uint16`    | Length of predicate, in instructions.                                  |
+| `predicateDataLength` | `uint16`    | Length of predicate input data, in bytes.                              |
+| `predicate`           | `byte[]`    | Predicate bytecode.                                                    |
+| `predicateData`       | `byte[]`    | Predicate input data (parameters).                                     |
+
+Transaction is invalid if:
+
+- `witnessIndex >= tx.witnessesCount`
+- `predicateLength > MAX_PREDICATE_LENGTH`
+- `predicateDataLength > MAX_PREDICATE_DATA_LENGTH`
+- If `predicateLength > 0`; the computed predicate root (see below) is not equal `owner`
+
+Note: the predicate root is computed identically to the contract ID, [here](./identifiers.md#contract-id).
+
 ## OutputType
 
 ```
 enum  OutputType : uint8 {
     Coin = 0,
     Contract = 1,
-    Withdrawal = 2,
+    Message = 2,
     Change = 3,
     Variable = 4,
     ContractCreated = 5,
@@ -257,7 +285,7 @@ enum  OutputType : uint8 {
 | name   | type                                                                                                                                                                                                                             | description     |
 |--------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
 | `type` | [OutputType](#outputtype)                                                                                                                                                                                                         | Type of output. |
-| `data` | One of [OutputCoin](#outputcoin), [OutputContract](#outputcontract), [OutputWithdrawal](#outputwithdrawal) [OutputChange](#outputchange), [OutputVariable](#outputvariable), or [OutputContractCreated](#outputcontractcreated). | Output data.    |
+| `data` | One of [OutputCoin](#outputcoin), [OutputContract](#outputcontract), [OutputMessage](#outputmessage) [OutputChange](#outputchange), [OutputVariable](#outputvariable), or [OutputContractCreated](#outputcontractcreated). | Output data.    |
 
 Transaction is invalid if:
 
@@ -294,15 +322,18 @@ The balance root `balanceRoot` is the root of the [SMT](./cryptographic_primitiv
 
 The state root `stateRoot` is the root of the [SMT](./cryptographic_primitives.md#sparse-merkle-tree) of storage slots. Each storage slot is a `byte[32]`, keyed by a `byte[32]`.
 
-### OutputWithdrawal
+### OutputMessage
 
-| name       | type       | description                  |
-|------------|------------|------------------------------|
-| `to`       | `byte[32]` | Receiving address.           |
-| `amount`   | `uint64`   | Amount of coins to withdraw. |
-| `asset_id` | `byte[32]` | Asset ID of coins.           |
+| name                  | type        | description                                                             |
+|-----------------------|-------------|-------------------------------------------------------------------------|
+| `messageID`           | `byte[32]`  | The messageID as described [here](./identifiers.md#message-id).         |
+| `sender`              | `byte[32]`  | The address of the message sender.                                      |
+| `recipient`           | `byte[32]`  | The address of the message recipient.                                   |
+| `callABI`             | `byte[]`    | The [abi encoded]([./abi.md](https://docs.soliditylang.org/en/v0.8.13/abi-spec.html)) call to execute.        |
+| `amount`              | `uint64`    | Amount of base asset coins sent with message.                           |
+| `nonce`               | `uint64`    | The message nonce.                                                      |
 
-This output type is unspendable and can be pruned form the UTXO set.
+This output type is unspendable and can be pruned from the UTXO set.
 
 ### OutputChange
 

specs/protocol/tx_validity.md

@@ -84,14 +84,14 @@ For each asset ID `asset_id` in the input and output set:
 def sum_inputs(tx, col) -> int:
     total: int = 0
     for input in tx.inputs:
-        if input.type == InputType.Coin and input.asset_id == col:
+        if (input.type == InputType.Coin and input.asset_id == col) or (input.type == InputType.Message and col == 0):
             total += input.amount
     return total
 
 def sum_outputs(tx, col) -> int:
     total: int = 0
     for output in tx.outputs:
-        if (output.type == OutputType.Coin or output.type == OutputType.Withdrawal) and output.asset_id == col:
+        if (output.type == OutputType.Coin and output.asset_id == col) or (output.type == OutputType.Message and col == 0):
             total += output.amount
     return total