syntax = "proto3";

package lnrpc;

import "lightning.proto";

option go_package = "github.com/lightningnetwork/lnd/lnrpc";

/*
 * Comments in this file will be directly parsed into the API
 * Documentation as descriptions of the associated method, message, or field.
 * These descriptions should go right above the definition of the object, and
 * can be in either block or // comment format.
 *
 * An RPC method can be matched to an lncli command by placing a line in the
 * beginning of the description in exactly the following format:
 * lncli: `methodname`
 *
 * Failure to specify the exact name of the command will cause documentation
 * generation to fail.
 *
 * More information on how exactly the gRPC documentation is generated from
 * this proto file can be found here:
 * https://github.com/lightninglabs/lightning-api
 */

// WalletUnlocker is a service that is used to set up a wallet password for
// lnd at first startup, and unlock a previously set up wallet.
service WalletUnlocker {
    /*
    GenSeed is the first method that should be used to instantiate a new lnd
    instance. This method allows a caller to generate a new aezeed cipher seed
    given an optional passphrase. If provided, the passphrase will be necessary
    to decrypt the cipherseed to expose the internal wallet seed.

    Once the cipherseed is obtained and verified by the user, the InitWallet
    method should be used to commit the newly generated seed, and create the
    wallet.
    */
    rpc GenSeed (GenSeedRequest) returns (GenSeedResponse);

    /*
    InitWallet is used when lnd is starting up for the first time to fully
    initialize the daemon and its internal wallet. At the very least a wallet
    password must be provided. This will be used to encrypt sensitive material
    on disk.

    In the case of a recovery scenario, the user can also specify their aezeed
    mnemonic and passphrase. If set, then the daemon will use this prior state
    to initialize its internal wallet.

    Alternatively, this can be used along with the GenSeed RPC to obtain a
    seed, then present it to the user. Once it has been verified by the user,
    the seed can be fed into this RPC in order to commit the new wallet.
    */
    rpc InitWallet (InitWalletRequest) returns (InitWalletResponse);

    /* lncli: `unlock`
    UnlockWallet is used at startup of lnd to provide a password to unlock
    the wallet database.
    */
    rpc UnlockWallet (UnlockWalletRequest) returns (UnlockWalletResponse);

    /* lncli: `changepassword`
    ChangePassword changes the password of the encrypted wallet. This will
    automatically unlock the wallet database if successful.
    */
    rpc ChangePassword (ChangePasswordRequest) returns (ChangePasswordResponse);
}

message GenSeedRequest {
    /*
    aezeed_passphrase is an optional user provided passphrase that will be used
    to encrypt the generated aezeed cipher seed. When using REST, this field
    must be encoded as base64.
    */
    bytes aezeed_passphrase = 1;

    /*
    seed_entropy is an optional 16-bytes generated via CSPRNG. If not
    specified, then a fresh set of randomness will be used to create the seed.
    When using REST, this field must be encoded as base64.
    */
    bytes seed_entropy = 2;
}
message GenSeedResponse {
    /*
    cipher_seed_mnemonic is a 24-word mnemonic that encodes a prior aezeed
    cipher seed obtained by the user. This field is optional, as if not
    provided, then the daemon will generate a new cipher seed for the user.
    Otherwise, then the daemon will attempt to recover the wallet state linked
    to this cipher seed.
    */
    repeated string cipher_seed_mnemonic = 1;

    /*
    enciphered_seed are the raw aezeed cipher seed bytes. This is the raw
    cipher text before run through our mnemonic encoding scheme.
    */
    bytes enciphered_seed = 2;
}

message InitWalletRequest {
    /*
    wallet_password is the passphrase that should be used to encrypt the
    wallet. This MUST be at least 8 chars in length. After creation, this
    password is required to unlock the daemon. When using REST, this field
    must be encoded as base64.
    */
    bytes wallet_password = 1;

    /*
    cipher_seed_mnemonic is a 24-word mnemonic that encodes a prior aezeed
    cipher seed obtained by the user. This may have been generated by the
    GenSeed method, or be an existing seed.
    */
    repeated string cipher_seed_mnemonic = 2;

    /*
    aezeed_passphrase is an optional user provided passphrase that will be used
    to encrypt the generated aezeed cipher seed. When using REST, this field
    must be encoded as base64.
    */
    bytes aezeed_passphrase = 3;

    /*
    recovery_window is an optional argument specifying the address lookahead
    when restoring a wallet seed. The recovery window applies to each
    individual branch of the BIP44 derivation paths. Supplying a recovery
    window of zero indicates that no addresses should be recovered, such after
    the first initialization of the wallet.
    */
    int32 recovery_window = 4;

    /*
    channel_backups is an optional argument that allows clients to recover the
    settled funds within a set of channels. This should be populated if the
    user was unable to close out all channels and sweep funds before partial or
    total data loss occurred. If specified, then after on-chain recovery of
    funds, lnd begin to carry out the data loss recovery protocol in order to
    recover the funds in each channel from a remote force closed transaction.
    */
    ChanBackupSnapshot channel_backups = 5;

    /*
    stateless_init is an optional argument instructing the daemon NOT to create
    any *.macaroon files in its filesystem. If this parameter is set, then the
    admin macaroon returned in the response MUST be stored by the caller of the
    RPC as otherwise all access to the daemon will be lost!
    */
    bool stateless_init = 6;

    /*
    extended_master_key is an alternative to specifying cipher_seed_mnemonic and
    aezeed_passphrase. Instead of deriving the master root key from the entropy
    of an aezeed cipher seed, the given extended master root key is used
    directly as the wallet's master key. This allows users to import/use a
    master key from another wallet. When doing so, lnd still uses its default
    SegWit only (BIP49/84) derivation paths and funds from custom/non-default
    derivation paths will not automatically appear in the on-chain wallet. Using
    an 'xprv' instead of an aezeed also has the disadvantage that the wallet's
    birthday is not known as that is an information that's only encoded in the
    aezeed, not the xprv. Therefore a birthday needs to be specified in
    extended_master_key_birthday_timestamp or a "safe" default value will be
    used.
    */
    string extended_master_key = 7;

    /*
    extended_master_key_birthday_timestamp is the optional unix timestamp in
    seconds to use as the wallet's birthday when using an extended master key
    to restore the wallet. lnd will only start scanning for funds in blocks that
    are after the birthday which can speed up the process significantly. If the
    birthday is not known, this should be left at its default value of 0 in
    which case lnd will start scanning from the first SegWit block (481824 on
    mainnet).
    */
    uint64 extended_master_key_birthday_timestamp = 8;

    /*
    watch_only is the third option of initializing a wallet: by importing
    account xpubs only and therefore creating a watch-only wallet that does not
    contain any private keys. That means the wallet won't be able to sign for
    any of the keys and _needs_ to be run with a remote signer that has the
    corresponding private keys and can serve signing RPC requests.
    */
    WatchOnly watch_only = 9;

    /*
    macaroon_root_key is an optional 32 byte macaroon root key that can be
    provided when initializing the wallet rather than letting lnd generate one
    on its own.
    */
    bytes macaroon_root_key = 10;
}
message InitWalletResponse {
    /*
    The binary serialized admin macaroon that can be used to access the daemon
    after creating the wallet. If the stateless_init parameter was set to true,
    this is the ONLY copy of the macaroon and MUST be stored safely by the
    caller. Otherwise a copy of this macaroon is also persisted on disk by the
    daemon, together with other macaroon files.
    */
    bytes admin_macaroon = 1;
}

message WatchOnly {
    /*
    The unix timestamp in seconds of when the master key was created. lnd will
    only start scanning for funds in blocks that are after the birthday which
    can speed up the process significantly. If the birthday is not known, this
    should be left at its default value of 0 in which case lnd will start
    scanning from the first SegWit block (481824 on mainnet).
    */
    uint64 master_key_birthday_timestamp = 1;

    /*
    The fingerprint of the root key (also known as the key with derivation path
    m/) from which the account public keys were derived from. This may be
    required by some hardware wallets for proper identification and signing. The
    bytes must be in big-endian order.
    */
    bytes master_key_fingerprint = 2;

    /*
    The list of accounts to import. There _must_ be an account for all of lnd's
    main key scopes: BIP49/BIP84 (m/49'/0'/0', m/84'/0'/0', note that the
    coin type is always 0, even for testnet/regtest) and lnd's internal key
    scope (m/1017'/<coin_type>'/<account>'), where account is the key family as
    defined in `keychain/derivation.go` (currently indices 0 to 9).
     */
    repeated WatchOnlyAccount accounts = 3;
}

message WatchOnlyAccount {
    /*
    Purpose is the first number in the derivation path, must be either 49, 84
    or 1017.
    */
    uint32 purpose = 1;

    /*
    Coin type is the second number in the derivation path, this is _always_ 0
    for purposes 49 and 84. It only needs to be set to 1 for purpose 1017 on
    testnet or regtest.
    */
    uint32 coin_type = 2;

    /*
    Account is the third number in the derivation path. For purposes 49 and 84
    at least the default account (index 0) needs to be created but optional
    additional accounts are allowed. For purpose 1017 there needs to be exactly
    one account for each of the key families defined in `keychain/derivation.go`
    (currently indices 0 to 9)
    */
    uint32 account = 3;

    /*
    The extended public key at depth 3 for the given account.
    */
    string xpub = 4;
}

message UnlockWalletRequest {
    /*
    wallet_password should be the current valid passphrase for the daemon. This
    will be required to decrypt on-disk material that the daemon requires to
    function properly. When using REST, this field must be encoded as base64.
    */
    bytes wallet_password = 1;

    /*
    recovery_window is an optional argument specifying the address lookahead
    when restoring a wallet seed. The recovery window applies to each
    individual branch of the BIP44 derivation paths. Supplying a recovery
    window of zero indicates that no addresses should be recovered, such after
    the first initialization of the wallet.
    */
    int32 recovery_window = 2;

    /*
    channel_backups is an optional argument that allows clients to recover the
    settled funds within a set of channels. This should be populated if the
    user was unable to close out all channels and sweep funds before partial or
    total data loss occurred. If specified, then after on-chain recovery of
    funds, lnd begin to carry out the data loss recovery protocol in order to
    recover the funds in each channel from a remote force closed transaction.
    */
    ChanBackupSnapshot channel_backups = 3;

    /*
    stateless_init is an optional argument instructing the daemon NOT to create
    any *.macaroon files in its file system.
    */
    bool stateless_init = 4;
}
message UnlockWalletResponse {
}

message ChangePasswordRequest {
    /*
    current_password should be the current valid passphrase used to unlock the
    daemon. When using REST, this field must be encoded as base64.
    */
    bytes current_password = 1;

    /*
    new_password should be the new passphrase that will be needed to unlock the
    daemon. When using REST, this field must be encoded as base64.
    */
    bytes new_password = 2;

    /*
    stateless_init is an optional argument instructing the daemon NOT to create
    any *.macaroon files in its filesystem. If this parameter is set, then the
    admin macaroon returned in the response MUST be stored by the caller of the
    RPC as otherwise all access to the daemon will be lost!
    */
    bool stateless_init = 3;

    /*
    new_macaroon_root_key is an optional argument instructing the daemon to
    rotate the macaroon root key when set to true. This will invalidate all
    previously generated macaroons.
    */
    bool new_macaroon_root_key = 4;
}
message ChangePasswordResponse {
    /*
    The binary serialized admin macaroon that can be used to access the daemon
    after rotating the macaroon root key. If both the stateless_init and
    new_macaroon_root_key parameter were set to true, this is the ONLY copy of
    the macaroon that was created from the new root key and MUST be stored
    safely by the caller. Otherwise a copy of this macaroon is also persisted on
    disk by the daemon, together with other macaroon files.
    */
    bytes admin_macaroon = 1;
}
