spl-token-2022 12.0.0

//! Token-metadata processor

use {
    pinocchio::{account::next_account_view, AccountView},
    solana_address::Address,
    solana_cpi::set_return_data,
    solana_msg::msg,
    solana_nullable::MaybeNull,
    solana_program_error::{ProgramError, ProgramResult},
    spl_token_2022_interface::{
        check_program_account,
        error::TokenError,
        extension::{
            alloc_and_serialize_variable_len_extension, metadata_pointer::MetadataPointer,
            BaseStateWithExtensions, PodStateWithExtensions,
        },
        pod::{PodCOption, PodMint},
    },
    spl_token_metadata_interface::{
        error::TokenMetadataError,
        instruction::{
            Emit, Initialize, RemoveKey, TokenMetadataInstruction, UpdateAuthority, UpdateField,
        },
        state::TokenMetadata,
    },
};

fn check_update_authority(
    update_authority_info: &AccountView,
    expected_update_authority: &MaybeNull<Address>,
) -> Result<(), ProgramError> {
    if !update_authority_info.is_signer() {
        return Err(ProgramError::MissingRequiredSignature);
    }
    let update_authority = Option::<Address>::from(*expected_update_authority)
        .ok_or(TokenMetadataError::ImmutableMetadata)?;
    if update_authority != *update_authority_info.address() {
        return Err(TokenMetadataError::IncorrectUpdateAuthority.into());
    }
    Ok(())
}

/// Processes a [`Initialize`](enum.TokenMetadataInstruction.html) instruction.
pub fn process_initialize(
    _program_id: &Address,
    accounts: &mut [AccountView],
    data: Initialize,
) -> ProgramResult {
    let account_info_iter = &mut accounts.iter_mut();

    let metadata_info = next_account_view(account_info_iter)?;
    let update_authority_info = next_account_view(account_info_iter)?;
    let mint_info = next_account_view(account_info_iter)?;
    let mint_authority_info = next_account_view(account_info_iter)?;

    // check that the mint and metadata accounts are the same, since the metadata
    // extension should only describe itself
    if metadata_info.address() != mint_info.address() {
        msg!("Metadata for a mint must be initialized in the mint itself.");
        return Err(TokenError::MintMismatch.into());
    }

    // scope the mint authority check, since the mint is in the same account!
    {
        check_program_account(mint_info.owner())?;
        let mint_data = mint_info.try_borrow()?;
        let mint = PodStateWithExtensions::<PodMint>::unpack(&mint_data)?;

        if !mint_authority_info.is_signer() {
            return Err(ProgramError::MissingRequiredSignature);
        }
        if mint.base.mint_authority != PodCOption::some(*mint_authority_info.address()) {
            return Err(TokenMetadataError::IncorrectMintAuthority.into());
        }

        if mint.get_extension::<MetadataPointer>().is_err() {
            msg!("A mint with metadata must have the metadata-pointer extension initialized");
            return Err(TokenError::InvalidExtensionCombination.into());
        }
    }

    // Create the token metadata
    let update_authority = Some(*update_authority_info.address())
        .try_into()
        .map_err(|_| ProgramError::InvalidArgument)?;
    let token_metadata = TokenMetadata {
        name: data.name,
        symbol: data.symbol,
        uri: data.uri,
        update_authority,
        mint: *mint_info.address(),
        ..Default::default()
    };

    // allocate a TLV entry for the space and write it in, assumes that there's
    // enough SOL for the new rent-exemption
    alloc_and_serialize_variable_len_extension::<PodMint, _>(
        metadata_info,
        &token_metadata,
        false,
    )?;

    Ok(())
}

/// Processes an [`UpdateField`](enum.TokenMetadataInstruction.html)
/// instruction.
pub fn process_update_field(
    _program_id: &Address,
    accounts: &mut [AccountView],
    data: UpdateField,
) -> ProgramResult {
    let account_info_iter = &mut accounts.iter_mut();
    let metadata_info = next_account_view(account_info_iter)?;
    let update_authority_info = next_account_view(account_info_iter)?;
    check_program_account(metadata_info.owner())?;

    // deserialize the metadata, but scope the data borrow since we'll probably
    // realloc the account
    let mut token_metadata = {
        let buffer = metadata_info.try_borrow()?;
        let mint = PodStateWithExtensions::<PodMint>::unpack(&buffer)?;
        mint.get_variable_len_extension::<TokenMetadata>()?
    };

    check_update_authority(update_authority_info, &token_metadata.update_authority)?;

    // Update the field
    token_metadata.update(data.field, data.value);

    // Update / realloc the account
    alloc_and_serialize_variable_len_extension::<PodMint, _>(metadata_info, &token_metadata, true)?;

    Ok(())
}

/// Processes a [`RemoveKey`](enum.TokenMetadataInstruction.html) instruction.
pub fn process_remove_key(
    _program_id: &Address,
    accounts: &mut [AccountView],
    data: RemoveKey,
) -> ProgramResult {
    let account_info_iter = &mut accounts.iter_mut();
    let metadata_info = next_account_view(account_info_iter)?;
    let update_authority_info = next_account_view(account_info_iter)?;
    check_program_account(metadata_info.owner())?;

    // deserialize the metadata, but scope the data borrow since we'll probably
    // realloc the account
    let mut token_metadata = {
        let buffer = metadata_info.try_borrow()?;
        let mint = PodStateWithExtensions::<PodMint>::unpack(&buffer)?;
        mint.get_variable_len_extension::<TokenMetadata>()?
    };

    check_update_authority(update_authority_info, &token_metadata.update_authority)?;
    if !token_metadata.remove_key(&data.key) && !data.idempotent {
        return Err(TokenMetadataError::KeyNotFound.into());
    }
    alloc_and_serialize_variable_len_extension::<PodMint, _>(metadata_info, &token_metadata, true)?;
    Ok(())
}

/// Processes a [`UpdateAuthority`](enum.TokenMetadataInstruction.html)
/// instruction.
pub fn process_update_authority(
    _program_id: &Address,
    accounts: &mut [AccountView],
    data: UpdateAuthority,
) -> ProgramResult {
    let account_info_iter = &mut accounts.iter_mut();
    let metadata_info = next_account_view(account_info_iter)?;
    let update_authority_info = next_account_view(account_info_iter)?;
    check_program_account(metadata_info.owner())?;

    // deserialize the metadata, but scope the data borrow since we'll write
    // to the account later
    let mut token_metadata = {
        let buffer = metadata_info.try_borrow()?;
        let mint = PodStateWithExtensions::<PodMint>::unpack(&buffer)?;
        mint.get_variable_len_extension::<TokenMetadata>()?
    };

    check_update_authority(update_authority_info, &token_metadata.update_authority)?;
    token_metadata.update_authority = data.new_authority;
    // Update the account, no realloc needed!
    alloc_and_serialize_variable_len_extension::<PodMint, _>(metadata_info, &token_metadata, true)?;

    Ok(())
}

/// Processes an [`Emit`](enum.TokenMetadataInstruction.html) instruction.
pub fn process_emit(_program_id: &Address, accounts: &[AccountView], data: Emit) -> ProgramResult {
    let account_info_iter = &mut accounts.iter();
    let metadata_info = next_account_view(account_info_iter)?;
    check_program_account(metadata_info.owner())?;

    let buffer = metadata_info.try_borrow()?;
    let state = PodStateWithExtensions::<PodMint>::unpack(&buffer)?;
    let metadata_bytes = state.get_extension_bytes::<TokenMetadata>()?;

    if let Some(range) = TokenMetadata::get_slice(metadata_bytes, data.start, data.end) {
        set_return_data(range);
    }
    Ok(())
}

/// Processes an [`Instruction`](enum.Instruction.html).
pub fn process_instruction(
    program_id: &Address,
    accounts: &mut [AccountView],
    instruction: TokenMetadataInstruction,
) -> ProgramResult {
    match instruction {
        TokenMetadataInstruction::Initialize(data) => {
            msg!("TokenMetadataInstruction: Initialize");
            process_initialize(program_id, accounts, data)
        }
        TokenMetadataInstruction::UpdateField(data) => {
            msg!("TokenMetadataInstruction: UpdateField");
            process_update_field(program_id, accounts, data)
        }
        TokenMetadataInstruction::RemoveKey(data) => {
            msg!("TokenMetadataInstruction: RemoveKey");
            process_remove_key(program_id, accounts, data)
        }
        TokenMetadataInstruction::UpdateAuthority(data) => {
            msg!("TokenMetadataInstruction: UpdateAuthority");
            process_update_authority(program_id, accounts, data)
        }
        TokenMetadataInstruction::Emit(data) => {
            msg!("TokenMetadataInstruction: Emit");
            process_emit(program_id, accounts, data)
        }
    }
}