/goal iteration 5 - unconfirmed

src/Simplex/Chat/Library/Commands.hs

@@ -58,8 +58,8 @@ import qualified Data.UUID.V4 as V4
 import Simplex.Chat.Library.Subscriber
 import Simplex.Chat.Badges (BadgeCredential (..), LocalBadge (..), badgeServerCredential, maxXFTPFileSize, mkBadgeStatus, verifyCredential)
 import Simplex.Chat.Names (SimplexDomainProof (..), SimplexDomainClaim (..), claimDomain, mkDomainClaim)
-import Simplex.Chat.Store.Wallets (accountHeldByOther, bindAccount, createWalletSeed, deleteWalletSeed, getNextAccountIndex, getUserAccounts, getWalletSeed)
-import Simplex.Chat.Wallet (AccountIndex, AccountKey, WalletAddress (..), WalletError (..), WalletSeed (..), accountSecret, checkAccountIndex, deriveAccountKey, entropyFromMnemonic, newSeedEntropy, renderAccountPath, seedMaster, seedMnemonic)
+import Simplex.Chat.Store.Wallets (WalletSeed (..), accountHeldByOther, bindAccount, createWalletSeed, deleteWalletSeed, getUserAccounts, getWalletSeed, resolveAccount)
+import Simplex.Chat.Wallet (AccountIndex, AccountKey, WalletAddress (..), WalletError (..), accountSecret, checkAccountIndex, deriveAccountKey, entropyFromMnemonic, newSeedEntropy, renderAccountPath, seedMaster, seedMnemonic)
 import Simplex.Messaging.Eth.Address (addressFromPrivateKey)
 import Simplex.Chat.Call
 import Simplex.Chat.Controller
@@ -1503,27 +1503,25 @@ processChatCommand cxt nm = \case
     unless created $ throwWalletError WEMasterExists
     processChatCommand cxt nm APIGetWallet
   APIBindWalletAccount accountIdx_ -> withUser $ \User {userId, viewPwdHash} -> do
-    seed <- walletSeed
     when (isJust viewPwdHash) $ throwWalletError WEHiddenProfile
-    _ <- liftWallet =<< withFastStore' (\db -> bindAccount db (wsId seed) userId accountIdx_)
+    liftWallet =<< withFastStore' (\db -> bindAccount db userId accountIdx_)
     processChatCommand cxt nm APIGetWallet
   APIGetWalletAddress accountIdx_ -> withUser $ \user -> do
-    seed <- walletSeed
-    n <- resolveAccount seed accountIdx_
+    (seed, n) <- liftWallet =<< withFastStore' (`resolveAccount` accountIdx_)
     CRWalletAddress user . accountAddress n <$> accountKey seed n
   APIExportWalletMnemonic -> withUser $ \user ->
-    CRWalletMnemonic user <$> (liftWallet . seedMnemonic =<< walletSeed)
-  APIExportWalletAccount accountIdx -> withUser $ \user@User {userId} -> do
+    CRWalletMnemonic user <$> (liftWallet . seedMnemonic . wsEntropy =<< walletSeed)
+  APIExportWalletAccount n -> withUser $ \user@User {userId} -> do
     seed <- walletSeed
-    n <- resolveAccount seed (Just accountIdx)
+    liftWallet $ checkAccountIndex n
     -- a key another profile holds is not this profile's to hand out
     heldByOther <- withFastStore' $ \db -> accountHeldByOther db (wsId seed) userId n
     when heldByOther $ throwWalletError WEAccountBound
     k <- accountKey seed n
     pure $ CRWalletAccountSecret user (accountAddress n k) (accountSecret k)
   APIDeleteWallet -> withUser $ \_ -> do
-    seed <- walletSeed
-    withFastStore' $ \db -> deleteWalletSeed db (wsId seed)
+    deleted <- withFastStore' deleteWalletSeed
+    unless deleted $ throwWalletError WENoMaster
     ok_
   APISendCallInvitation contactId callType -> withUser $ \user -> do
     -- party initiating call
@@ -5470,19 +5468,8 @@ throwWalletError = throwChatError . CEWallet
 liftWallet :: Either WalletError a -> CM a
 liftWallet = either throwWalletError pure
 
--- | The account a command names, or the next free one when it names none.
--- Refuses any index BIP-32 cannot harden, the counter's included.
-resolveAccount :: WalletSeed -> Maybe AccountIndex -> CM AccountIndex
-resolveAccount seed accountIdx_ = do
-  n <- maybe nextFreeAccount pure accountIdx_
-  n <$ liftWallet (checkAccountIndex n)
-  where
-    nextFreeAccount =
-      withFastStore' (\db -> getNextAccountIndex db (wsId seed))
-        >>= maybe (throwWalletError WECounterUnknown) pure
-
 accountKey :: WalletSeed -> AccountIndex -> CM AccountKey
-accountKey seed n = liftWallet $ seedMaster seed >>= (`deriveAccountKey` n)
+accountKey seed n = liftWallet $ seedMaster (wsEntropy seed) >>= (`deriveAccountKey` n)
 
 accountAddress :: AccountIndex -> AccountKey -> WalletAddress
 accountAddress n k =
@@ -6156,12 +6143,15 @@ chatCommandP =
     quotedP = safeDecodeUtf8 <$> (A.char '"' *> A.takeTill (== '"') <* A.char '"')
     text1P = safeDecodeUtf8 <$> A.takeTill (== ' ')
     char_ = optional . A.char
-    -- Digits are counted before they are read, as reading a very long number is
-    -- not free. The hardening bound is a typed error when the command runs.
+    -- The digits are counted before they are read, as reading a very long
+    -- number is not free. Ten of them fit an Int with room to spare, and the
+    -- hardening bound is a typed error when the command runs, so that a caller
+    -- is told which index was refused and why.
     accountIndexP = do
       ds <- A.takeWhile1 isDigit
-      let i = read (B.unpack ds) :: Integer
-      if B.length ds <= 10 && i <= toInteger (maxBound :: AccountIndex) then pure (fromIntegral i) else fail "account index too large"
+      case if B.length ds <= 10 then B.readInt ds else Nothing of
+        Just (i, _) | i <= fromIntegral (maxBound :: AccountIndex) -> pure $ fromIntegral i
+        _ -> fail "account index too large"
 
 displayNameP :: Parser Text
 displayNameP = safeDecodeUtf8 <$> displayNameP_

src/Simplex/Chat/Store/Postgres/Migrations.hs

@@ -99,7 +99,7 @@ schemaMigrations =
     ("20260813_auto_accept_group_invitations", m20260813_auto_accept_group_invitations, Just down_m20260813_auto_accept_group_invitations),
     ("20260822_forward_link", m20260822_forward_link, Just down_m20260822_forward_link),
     ("20260828_file_expiry", m20260828_file_expiry, Just down_m20260828_file_expiry),
-    ("20260908_wallet_seeds", m20260908_wallet_seeds, Just down_m20260908_wallet_seeds)
+    ("20260908_wallet_seeds", m20260908_wallet_seeds, Nothing)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/Postgres/Migrations/M20260908_wallet_seeds.hs

@@ -9,10 +9,10 @@ import Text.RawString.QQ (r)
 m20260908_wallet_seeds :: Text
 m20260908_wallet_seeds =
   [r|
+-- the columns are commented in the SQLite migration
 CREATE TABLE wallet_seeds (
   wallet_seed_id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
   entropy BYTEA NOT NULL CHECK (length(entropy) = 32),
-  -- see the SQLite migration
   next_account_index BIGINT CHECK (next_account_index BETWEEN 0 AND 2147483648),
   single_seed SMALLINT NOT NULL DEFAULT 1
 );
@@ -25,20 +25,8 @@ CREATE TABLE wallet_accounts (
 );
 
 CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
-CREATE UNIQUE INDEX idx_wallet_accounts_index ON wallet_accounts(wallet_seed_id, account_index);
-CREATE INDEX idx_wallet_accounts_user ON wallet_accounts(user_id);
+CREATE UNIQUE INDEX idx_wallet_accounts_wallet_seed_id_account_index ON wallet_accounts(wallet_seed_id, account_index);
+CREATE INDEX idx_wallet_accounts_user_id ON wallet_accounts(user_id);
 |]
 
-down_m20260908_wallet_seeds :: Text
-down_m20260908_wallet_seeds =
-  [r|
-DROP INDEX idx_wallet_accounts_user;
-
-DROP INDEX idx_wallet_accounts_index;
-
-DROP INDEX idx_wallet_seeds_single_seed;
-
-DROP TABLE wallet_accounts;
-
-DROP TABLE wallet_seeds;
-|]
+-- no reverse step, see the SQLite migration

src/Simplex/Chat/Store/Postgres/Migrations/chat_schema.sql

@@ -1533,11 +1533,34 @@ ALTER TABLE test_chat_schema.users ALTER COLUMN user_id ADD GENERATED ALWAYS AS
 
 
 
+CREATE TABLE test_chat_schema.wallet_accounts (
+    wallet_account_id bigint NOT NULL,
+    wallet_seed_id bigint NOT NULL,
+    account_index bigint,
+    user_id bigint,
+    CONSTRAINT wallet_accounts_account_index_check CHECK (((account_index >= 0) AND (account_index <= 2147483647)))
+);
+
+
+
+ALTER TABLE test_chat_schema.wallet_accounts ALTER COLUMN wallet_account_id ADD GENERATED ALWAYS AS IDENTITY (
+    SEQUENCE NAME test_chat_schema.wallet_accounts_wallet_account_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1
+);
+
+
+
 CREATE TABLE test_chat_schema.wallet_seeds (
     wallet_seed_id bigint NOT NULL,
     entropy bytea NOT NULL,
-    next_name_index bigint DEFAULT 1 NOT NULL,
-    single_seed smallint DEFAULT 1 NOT NULL
+    next_account_index bigint,
+    single_seed smallint DEFAULT 1 NOT NULL,
+    CONSTRAINT wallet_seeds_entropy_check CHECK ((length(entropy) = 32)),
+    CONSTRAINT wallet_seeds_next_account_index_check CHECK (((next_account_index >= 0) AND (next_account_index <= '2147483648'::bigint)))
 );
 
 
@@ -1911,6 +1934,11 @@ ALTER TABLE ONLY test_chat_schema.users
 
 
 
+ALTER TABLE ONLY test_chat_schema.wallet_accounts
+    ADD CONSTRAINT wallet_accounts_pkey PRIMARY KEY (wallet_account_id);
+
+
+
 ALTER TABLE ONLY test_chat_schema.wallet_seeds
     ADD CONSTRAINT wallet_seeds_pkey PRIMARY KEY (wallet_seed_id);
 
@@ -2665,6 +2693,14 @@ CREATE UNIQUE INDEX idx_user_contact_links_group_id ON test_chat_schema.user_con
 
 
 
+CREATE INDEX idx_wallet_accounts_user_id ON test_chat_schema.wallet_accounts USING btree (user_id);
+
+
+
+CREATE UNIQUE INDEX idx_wallet_accounts_wallet_seed_id_account_index ON test_chat_schema.wallet_accounts USING btree (wallet_seed_id, account_index);
+
+
+
 CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON test_chat_schema.wallet_seeds USING btree (single_seed);
 
 
@@ -3344,6 +3380,16 @@ ALTER TABLE ONLY test_chat_schema.user_contact_links
 
 
 
+ALTER TABLE ONLY test_chat_schema.wallet_accounts
+    ADD CONSTRAINT wallet_accounts_user_id_fkey FOREIGN KEY (user_id) REFERENCES test_chat_schema.users(user_id) ON DELETE SET NULL;
+
+
+
+ALTER TABLE ONLY test_chat_schema.wallet_accounts
+    ADD CONSTRAINT wallet_accounts_wallet_seed_id_fkey FOREIGN KEY (wallet_seed_id) REFERENCES test_chat_schema.wallet_seeds(wallet_seed_id) ON DELETE CASCADE;
+
+
+
 ALTER TABLE ONLY test_chat_schema.xftp_file_descriptions
     ADD CONSTRAINT xftp_file_descriptions_user_id_fkey FOREIGN KEY (user_id) REFERENCES test_chat_schema.users(user_id) ON DELETE CASCADE;
 

src/Simplex/Chat/Store/SQLite/Migrations.hs

@@ -345,7 +345,7 @@ schemaMigrations =
     ("20260813_auto_accept_group_invitations", m20260813_auto_accept_group_invitations, Just down_m20260813_auto_accept_group_invitations),
     ("20260822_forward_link", m20260822_forward_link, Just down_m20260822_forward_link),
     ("20260828_file_expiry", m20260828_file_expiry, Just down_m20260828_file_expiry),
-    ("20260908_wallet_seeds", m20260908_wallet_seeds, Just down_m20260908_wallet_seeds)
+    ("20260908_wallet_seeds", m20260908_wallet_seeds, Nothing)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/SQLite/Migrations/M20260908_wallet_seeds.hs

@@ -23,20 +23,11 @@ CREATE TABLE wallet_accounts (
 ) STRICT;
 
 CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
-CREATE UNIQUE INDEX idx_wallet_accounts_index ON wallet_accounts(wallet_seed_id, account_index);
-CREATE INDEX idx_wallet_accounts_user ON wallet_accounts(user_id);
+CREATE UNIQUE INDEX idx_wallet_accounts_wallet_seed_id_account_index ON wallet_accounts(wallet_seed_id, account_index);
+CREATE INDEX idx_wallet_accounts_user_id ON wallet_accounts(user_id);
 |]
 
-down_m20260908_wallet_seeds :: Query
-down_m20260908_wallet_seeds =
-  [sql|
-DROP INDEX idx_wallet_accounts_user;
-
-DROP INDEX idx_wallet_accounts_index;
-
-DROP INDEX idx_wallet_seeds_single_seed;
-
-DROP TABLE wallet_accounts;
-
-DROP TABLE wallet_seeds;
-|]
+-- There is no reverse step. Reversing this would drop the only copy of the
+-- master entropy, and a downgrade that takes every key on the device with it is
+-- worse than one that refuses: without a reverse step the older app reports that
+-- the database is newer than it is and changes nothing.

src/Simplex/Chat/Store/SQLite/Migrations/chat_schema.sql

@@ -1399,11 +1399,11 @@ CREATE INDEX idx_chat_items_item_signed_by_group_member_id ON chat_items(
   item_signed_by_group_member_id
 );
 CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
-CREATE UNIQUE INDEX idx_wallet_accounts_index ON wallet_accounts(
+CREATE UNIQUE INDEX idx_wallet_accounts_wallet_seed_id_account_index ON wallet_accounts(
   wallet_seed_id,
   account_index
 );
-CREATE INDEX idx_wallet_accounts_user ON wallet_accounts(user_id);
+CREATE INDEX idx_wallet_accounts_user_id ON wallet_accounts(user_id);
 CREATE TRIGGER on_group_members_insert_update_summary
 AFTER INSERT ON group_members
 FOR EACH ROW

src/Simplex/Chat/Store/Wallets.hs

@@ -1,28 +1,31 @@
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE TypeApplications #-}
 
 -- | The device seed, and which chat profile each account belongs to.
 module Simplex.Chat.Store.Wallets
-  ( getWalletSeed,
+  ( SeedId,
+    WalletSeed (..),
+    getWalletSeed,
     createWalletSeed,
     deleteWalletSeed,
-    getNextAccountIndex,
+    resolveAccount,
     getUserAccounts,
     accountHeldByOther,
     bindAccount,
   )
 where
 
-import Control.Monad (join, when)
+import Control.Monad (join, unless, when)
 import Control.Monad.Except
 import Control.Monad.IO.Class (liftIO)
 import qualified Data.ByteArray as BA
 import Data.ByteString (ByteString)
 import Data.Int (Int64)
-import Simplex.Chat.Wallet (AccountIndex, SeedId, WalletError (..), WalletSeed (..), checkAccountIndex)
+import Simplex.Chat.Wallet (AccountIndex, WalletError (..), checkAccountIndex)
 import Simplex.Messaging.Agent.Protocol (UserId)
 import Simplex.Messaging.Agent.Store.AgentStore (maybeFirstRow)
 import qualified Simplex.Messaging.Agent.Store.DB as DB
@@ -35,6 +38,17 @@ import Database.SQLite.Simple (Only (..))
 import Database.SQLite.Simple.QQ (sql)
 #endif
 
+type SeedId = Int64
+
+-- | The device seed, as a row: the id the account rows are counted against, and
+-- the entropy every key is derived from. The entropy is 'BA.ScrubbedBytes', so
+-- a derived 'Show' does not print it.
+data WalletSeed = WalletSeed
+  { wsId :: SeedId,
+    wsEntropy :: BA.ScrubbedBytes
+  }
+  deriving (Show)
+
 toSeed :: (Int64, ByteString) -> WalletSeed
 toSeed (sId, entropy) = WalletSeed {wsId = sId, wsEntropy = BA.convert entropy}
 
@@ -56,8 +70,26 @@ createWalletSeed db entropy nextAccount =
           "INSERT INTO wallet_seeds (entropy, next_account_index) VALUES (?, ?)"
           (DB.Binary (BA.convert entropy :: ByteString), accountIndexCol <$> nextAccount)
 
-deleteWalletSeed :: DB.Connection -> SeedId -> IO ()
-deleteWalletSeed db sId = DB.execute db "DELETE FROM wallet_seeds WHERE wallet_seed_id = ?" (Only sId)
+-- | False if the device had no seed to delete. The account rows go with it.
+deleteWalletSeed :: DB.Connection -> IO Bool
+deleteWalletSeed db =
+  getWalletSeed db >>= \case
+    Nothing -> pure False
+    Just WalletSeed {wsId} ->
+      True <$ DB.execute db "DELETE FROM wallet_seeds WHERE wallet_seed_id = ?" (Only wsId)
+
+-- | The seed, and the account an argument names or the next free one from the
+-- counter when it names none. Refuses an index BIP-32 cannot harden, the
+-- counter's included. The seed comes back with it so that a caller derives from
+-- the one the index was resolved against.
+resolveAccount :: DB.Connection -> Maybe AccountIndex -> IO (Either WalletError (WalletSeed, AccountIndex))
+resolveAccount db accountIdx_ = runExceptT $ do
+  seed <- ExceptT $ maybe (Left WENoMaster) Right <$> getWalletSeed db
+  n <- maybe (nextFreeAccount $ wsId seed) pure accountIdx_
+  liftEither $ checkAccountIndex n
+  pure (seed, n)
+  where
+    nextFreeAccount sId = ExceptT $ maybe (Left WECounterUnknown) Right <$> getNextAccountIndex db sId
 
 -- | The index the next account takes. Nothing after an import, where the phrase
 -- does not say how many accounts it has been used for.
@@ -87,9 +119,10 @@ accountUser db sId n =
   maybeFirstRow (fromOnly @(Maybe Int64)) $
     DB.query db "SELECT user_id FROM wallet_accounts WHERE wallet_seed_id = ? AND account_index = ?" (sId, accountIndexCol n)
 
--- | True when a profile other than this one holds the account, which is what
--- keeps one profile from exporting another profile's key. An account no profile
--- holds is not another profile's.
+-- | True when a profile other than this one holds the account, which keeps one
+-- profile from handing out another's account key. It is a guard, not a
+-- boundary: @export master@ reaches every account from any profile. An account
+-- no profile holds is not another profile's.
 heldByOther :: UserId -> Maybe (Maybe Int64) -> Bool
 heldByOther userId = \case
   Just (Just heldBy) -> heldBy /= userId
@@ -99,32 +132,37 @@ accountHeldByOther :: DB.Connection -> SeedId -> UserId -> AccountIndex -> IO Bo
 accountHeldByOther db sId userId n = heldByOther userId <$> accountUser db sId n
 
 -- | Bind an account to a profile: one the device already knows about, one a
--- scan found, or the next free one when no index is given. Reading the counter
--- and taking the account happen in one transaction, so two binds racing cannot
--- both take it.
-bindAccount :: DB.Connection -> SeedId -> UserId -> Maybe AccountIndex -> IO (Either WalletError AccountIndex)
-bindAccount db sId userId accountIdx_ = runExceptT $ do
-  n <- maybe nextFreeAccount pure accountIdx_
-  liftEither $ checkAccountIndex n
+-- scan found, or the next free one when no index is given. The whole command is
+-- one transaction, so nothing between reading the counter and taking the
+-- account can hand the same one out twice.
+bindAccount :: DB.Connection -> UserId -> Maybe AccountIndex -> IO (Either WalletError ())
+bindAccount db userId accountIdx_ = runExceptT $ do
+  (WalletSeed {wsId = sId}, n) <- ExceptT $ resolveAccount db accountIdx_
   held <- liftIO $ accountUser db sId n
   when (heldByOther userId held) $ throwError WEAccountBound
-  liftIO $ do
-    case held of
-      Just (Just _) -> pure () -- already this profile's
-      Just Nothing -> setAccountUser db sId userId n
-      Nothing -> insertAccount db sId userId n
-    raiseNextAccount db sId n
-  pure n
-  where
-    nextFreeAccount = ExceptT $ maybe (Left WECounterUnknown) Right <$> getNextAccountIndex db sId
+  taken <- liftIO $ case held of
+    Just (Just _) -> pure True -- already this profile's
+    -- the update takes the account only while no profile holds it, and the read
+    -- after it says whether this one got it: where transactions are not
+    -- serialised, two of them can both read the account as free
+    Just Nothing -> setAccountUser db sId userId n >> accountHeldBy db sId userId n
+    Nothing -> True <$ insertAccount db sId userId n
+  unless taken $ throwError WEAccountBound
+  liftIO $ raiseNextAccount db sId n
 
 setAccountUser :: DB.Connection -> SeedId -> UserId -> AccountIndex -> IO ()
 setAccountUser db sId userId n =
   DB.execute
     db
-    [sql| UPDATE wallet_accounts SET user_id = ? WHERE wallet_seed_id = ? AND account_index = ? |]
+    [sql|
+      UPDATE wallet_accounts SET user_id = ?
+      WHERE wallet_seed_id = ? AND account_index = ? AND user_id IS NULL
+    |]
     (userId, sId, accountIndexCol n)
 
+accountHeldBy :: DB.Connection -> SeedId -> UserId -> AccountIndex -> IO Bool
+accountHeldBy db sId userId n = (== Just (Just userId)) <$> accountUser db sId n
+
 -- | Keep the counter a high-water mark, so an account taken by index is not
 -- handed out again as the next free one. Never lowers it, and never gives a
 -- value to the imported phrase that has none.

src/Simplex/Chat/Wallet.hs

@@ -10,10 +10,8 @@
 -- Nothing here knows about chat profiles. Which profile an account belongs to is
 -- a mapping in "Simplex.Chat.Store.Wallets".
 module Simplex.Chat.Wallet
-  ( SeedId,
-    AccountIndex,
+  ( AccountIndex,
     AccountKey,
-    WalletSeed (..),
     WalletAddress (..),
     WalletError (..),
     newSeedEntropy,
@@ -33,7 +31,6 @@ import qualified Data.Aeson.TH as JQ
 import qualified Data.ByteArray as BA
 import qualified Data.ByteArray.Encoding as BAE
 import Data.ByteString (ByteString)
-import Data.Int (Int64)
 import Data.Text (Text)
 import Data.Text.Encoding (decodeLatin1)
 import Data.Word (Word32)
@@ -43,8 +40,6 @@ import qualified Simplex.Messaging.Crypto.Secp256k1 as S
 import Simplex.Messaging.Eth.Address (ethereumPath)
 import Simplex.Messaging.Parsers (defaultJSON, dropPrefix, sumTypeJSON)
 
-type SeedId = Int64
-
 -- | BIP-44 account index. One account owns one thing on chain, one name to
 -- begin with.
 type AccountIndex = Word32
@@ -52,15 +47,6 @@ type AccountIndex = Word32
 -- | The key at an account index. It owns whatever that account owns.
 type AccountKey = S.PrivateKey
 
--- | The device seed. The entropy is 'BA.ScrubbedBytes', so a derived 'Show'
--- does not print it. Copies made for BIP-39 are plain 'ByteString' and are not
--- wiped.
-data WalletSeed = WalletSeed
-  { wsId :: SeedId,
-    wsEntropy :: BA.ScrubbedBytes
-  }
-  deriving (Eq, Show)
-
 -- | One derived address, with the index it came from, so a caller that left the
 -- index out knows what it got.
 data WalletAddress = WalletAddress
@@ -101,14 +87,14 @@ entropyFromMnemonic phrase = case B39.parseMnemonic phrase of
     Right . BA.convert $ B39.mnemonicToEntropy m
   _ -> Left WEBadMnemonic
 
-seedMnemonic :: WalletSeed -> Either WalletError Text
-seedMnemonic s =
-  bipError . fmap (decodeLatin1 . B39.mnemonicPhrase) . B39.entropyToMnemonic $ entropyBytes s
+seedMnemonic :: BA.ScrubbedBytes -> Either WalletError Text
+seedMnemonic entropy =
+  bipError . fmap (decodeLatin1 . B39.mnemonicPhrase) . B39.entropyToMnemonic $ entropyBytes entropy
 
 -- | Deriving this runs PBKDF2, so it is done once per command.
-seedMaster :: WalletSeed -> Either WalletError B32.ExtendedKey
-seedMaster s = do
-  m <- bipError . B39.entropyToMnemonic $ entropyBytes s
+seedMaster :: BA.ScrubbedBytes -> Either WalletError B32.ExtendedKey
+seedMaster entropy = do
+  m <- bipError . B39.entropyToMnemonic $ entropyBytes entropy
   bipError . B32.masterKey $ B39.mnemonicToSeed m ""
 
 accountPath :: AccountIndex -> [Word32]
@@ -124,8 +110,9 @@ deriveAccountKey master n = B32.xkKey <$> bipError (B32.derivePath master $ acco
 accountSecret :: AccountKey -> Text
 accountSecret k = "0x" <> decodeLatin1 (BAE.convertToBase BAE.Base16 $ S.unPrivateKey k)
 
-entropyBytes :: WalletSeed -> ByteString
-entropyBytes = BA.convert . wsEntropy
+-- | The copy BIP-39 takes is a plain 'ByteString' and is not wiped.
+entropyBytes :: BA.ScrubbedBytes -> ByteString
+entropyBytes = BA.convert
 
 -- | The BIP-32 and BIP-39 functions report failure as a string. For entropy
 -- this module produced only 'B32.masterKey' and 'B32.derivePath' can fail at