# Wallet V4 (https://docs-i0yym09dy-ton-core-docs.vercel.app/llms/standard/wallets/v4/content.md)
| Contract version | Hash | Link |
| ---------------- | ------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------- |
| V4 R1 | `64dd54805522c5be8a9db59cea0105ccf0d08786ca79beb8cb79e880a8d7322d` | [Source](https://github.com/ton-blockchain/wallet-contract/blob/0f9e25acd61a8384887f4d6c017b8cdbd7cf2213/func/wallet-v4-code.fc) |
| V4 R2 | `feb5ff6820e2ff0d9483e7e0d62c817d846789fb4ae580c878866d959dabd5c0` | [Source](https://github.com/ton-blockchain/wallet-contract/blob/4111fd9e3313ec17d99ca9b5b1656445b5b49d8f/func/wallet-v4-code.fc) |
This version retains all the functionality of the previous versions and introduces plugins.
Plugins enable developers to implement custom logic that integrates with wallet functionality. When a plugin is installed on a wallet through a signed transaction, it can force wallet to send internal message with predefined opcode (`0xf06c7567`) and any available Toncoin amount to specified addresses. Plugins are separate smart contracts that can implement their own custom logic.
View the original [wallet V4 source code](https://github.com/ton-blockchain/wallet-contract) or the code of an [example subscription plugin](https://github.com/ton-blockchain/wallet-contract/blob/main/func/simple-subscription-plugin.fc).
## Plugins [#plugins]
Installing third-party plugins can be dangerous and may lead to wallet drainage. Only install plugins from trusted sources and ensure you understand their functionality before installation.
Due to security reasons mentioned above, it is not possible to install plugins using [TON Connect](/llms/ecosystem/ton-connect/overview/content.md).
Plugins are essentially other smart contracts on TON that developers are free to implement as they wish. In relation to the wallet, they are simply addresses of smart contracts stored in a dictionary in the wallet's persistent memory. These plugins are allowed to request funds and remove themselves from the "allowed list" by sending internal messages to the wallet.
### Plugin interaction flow [#plugin-interaction-flow]
## Persistent memory layout [#persistent-memory-layout]
Here we will break down wallet V4 storage structure.
```tlb
contract_state$_
seqno:(## 32)
wallet_id:(## 32)
public_key:(## 256)
plugins:(HashmapE 256 int1) = ContractState;
```
* `seqno`: 32-bit long sequence number.
* `wallet_id`: 32-bit long wallet\_id. This is a number that allows you to create multiple wallets with the same private key but different addresses.
* `public_key`: 256-bit long public key.
* `plugins`: dictionary containing plugins (may be empty).
Default value for wallet\_id is `698983191` in V4, it is a partial hash of TON Mainnet zero state.
## Receiving internal messages [#receiving-internal-messages]
All previous versions of wallets had a straightforward implementation for receiving internal messages. They simply accepted incoming funds from any sender, ignoring the internal message body if present, or in other words, they had an empty `recv_internal` method. However, as mentioned earlier, the fourth version of the wallet introduces two additional available operations. Let's take a look at the internal message body layout:
* `opcode` (optional): 32-bit long operation code. This is an optional field. Any message containing less than 32 bits in the message body, an incorrect opcode, or a sender address that isn't registered as a plugin will be considered a simple transfer, similar to previous wallet versions.
* `query_id`: 64-bit long integer. This field has no effect on the smart contract's behavior; it is used to track chains of messages between contracts.
1. opcode = `0x706c7567`, request funds operation.
* `amount`: [Coins](/llms/tvm/instructions/content.md) amount of requested Toncoin.
* `extra_currencies`: dictionary containing the amount of requested extra currencies (may be empty).
2. opcode = `0x64737472`, request removal of the plugin that sent this message from the allowed list.
TL-B for plugin operations:
```tlb
request_funds#706c7567
amount:Coins
extra_currencies:ExtraCurrencyCollection = InternalMsgBody;
self_destroy#64737472 = InternalMsgBody;
```
## External message body layout [#external-message-body-layout]
* `signature`: 512-bit long [Ed25519](https://en.wikipedia.org/wiki/EdDSA#Ed25519) signature.
* `wallet_id`: 32-bit long subwallet ID.
* `valid_until`: 32-bit long Unix time integer.
* `msg_seqno`: 32-bit long sequence number.
* `opcode`: 32-bit long operation code.
* other data depending on the opcode
Next, let's explore the types of messages:
### Simple send (opcode = 0x0) [#simple-send-opcode--0x0]
The simple send operation processes a chain of messages, where each message contains a mode and a reference to the actual message cell:
**Processing logic:**
```func
if (op == 0) { ;; simple send
while (cs.slice_refs()) {
var mode = cs~load_uint(8);
send_raw_message(cs~load_ref(), mode);
}
}
```
* `mode`: up to four 8-bit integers defining the sending mode for each message.
* `out_msg`: up to four references to cells containing messages.
### Deploy and install plugin (opcode = 0x1) [#deploy-and-install-plugin-opcode--0x1]
```tlb
deploy_and_install_plugin#01
workchain:(## 8)
balance:Coins
state_init:^Cell
body:^Cell
= WalletAction;
```
Deploys a new plugin contract and adds it to the wallet's plugin allowlist:
* `workchain`: 8-bit workchain ID where the plugin will be deployed
* `balance`: Initial Toncoin balance for the plugin contract
* `state_init`: Cell reference containing the plugin's initial state and code
* `body`: Cell reference containing the deployment message body
### Install plugin (opcode = 0x2) [#install-plugin-opcode--0x2]
```tlb
wc_n_address#_ wc:(## 8) hash:(## 256) = WorkchainWithAddress;
install_plugin#02
wc_n_address:WorkchainWithAddress
balance:Coins
query_id:(## 64)
= WalletAction;
```
Adds an existing plugin contract to the wallet's allowlist:
* `wc_n_address`: Combined 8-bit workchain ID and 256-bit plugin address
* `balance`: Toncoin amount to send during installation
* `query_id`: 64-bit identifier for tracking the operation
### Remove plugin (opcode = 0x3) [#remove-plugin-opcode--0x3]
```tlb
wc_n_address#_ wc:(## 8) hash:(## 256) = WorkchainWithAddress;
remove_plugin#03
wc_n_address:WorkchainWithAddress
balance:Coins
query_id:(## 64)
= WalletAction;
```
Removes a plugin from the wallet's allowlist:
* `wc_n_address`: Combined 8-bit workchain ID and 256-bit plugin address
* `balance`: Toncoin amount
* `query_id`: 64-bit identifier for tracking the operation
Wallet V4 provides standard functionality through the `0x0` opcode, similar to previous versions (see [wallet overview](/llms/standard/wallets/history/content.md) for details on message layout). The `0x2` and `0x3` operations allow manipulation of the plugin dictionary.
## Exit codes [#exit-codes]
| Exit code | Description |
| --------- | ----------------------------------------------------------------------- |
| 33 | `seqno` check failed, replay protection triggered |
| 34 | `wallet_id` does not match the stored one |
| 35 | `signature` check failed |
| 36 | `valid_until` check failed, transaction attempted too late |
| 39 | Plugins dictionary manipulation failed (0x1-0x3 recv\_external opcodes) |
| 80 | Not enough funds for the plugin funds request |
| 0 | Standard successful execution exit code. |
## Get methods [#get-methods]
1. `int seqno()` returns current stored seqno.
2. `int get_public_key()` returns current stored public key.
3. `int get_subwallet_id()` returns current subwallet ID.
4. `int is_plugin_installed(int wc, int addr_hash)` checks if plugin with defined workchain\_id and address hash is installed. Returns `-1` (true) if the plugin is installed, `0` (false) if not installed.
5. `tuple get_plugin_list()` returns list of plugins.