Fix address pool panics on start up

dcrwallet.go

@@ -6,6 +6,7 @@
 package main
 
 import (
+	"bufio"
 	"io/ioutil"
 	"net"
 	"net/http"
@@ -16,7 +17,10 @@ import (
 	"sync"
 	"time"
 
+	"github.com/decred/dcrd/chaincfg"
 	"github.com/decred/dcrwallet/chain"
+	"github.com/decred/dcrwallet/internal/prompt"
+	"github.com/decred/dcrwallet/internal/zero"
 	"github.com/decred/dcrwallet/rpc/legacyrpc"
 	"github.com/decred/dcrwallet/wallet"
 )
@@ -112,6 +116,7 @@ func walletMain() error {
 	}
 
 	loader.RunAfterLoad(func(w *wallet.Wallet) {
+		startPromptPass(w)
 		startWalletRPCServices(w, rpcs, legacyRPCServer)
 	})
 
@@ -160,6 +165,66 @@ func walletMain() error {
 	return nil
 }
 
+// startPromptPass prompts the user for a password to unlock their wallet in
+// the event that it was restored from seed or --promptpass flag is set.
+func startPromptPass(w *wallet.Wallet) {
+	promptPass := cfg.PromptPass
+
+	// The wallet is totally desynced, so we need to resync accounts.
+	// Prompt for the password. Then, set the flag it wallet so it
+	// knows which address functions to call when resyncing.
+	firstRunBS := w.Manager.SyncedTo()
+	if firstRunBS.Hash == *w.ChainParams().GenesisHash {
+		promptPass = true
+	}
+	if promptPass {
+		w.SetResyncAccounts(true)
+		log.Infof("Please enter the private wallet passphrase. " +
+			"This will complete syncing of the wallet accounts " +
+			"and then leave your wallet unlocked. You may relock " +
+			"wallet after by calling 'walletlock' through the RPC.")
+	} else {
+		return
+	}
+
+	// We need to rescan accounts for the initial sync. Unlock the
+	// wallet after prompting for the passphrase. The special case
+	// of a --createtemp simnet wallet is handled by first
+	// attempting to automatically open it with the default
+	// passphrase. The wallet should also request to be unlocked
+	// if stake mining is currently on, so users with this flag
+	// are prompted here as well.
+	for {
+		if w.ChainParams() == &chaincfg.SimNetParams {
+			var unlockAfter <-chan time.Time
+			err := w.Unlock(wallet.SimulationPassphrase, unlockAfter)
+			if err == nil {
+				// Unlock success with the default password.
+				return
+			}
+		}
+		if promptPass {
+			reader := bufio.NewReader(os.Stdin)
+			passphrase, err := prompt.PromptPass(reader, "", false)
+			if err != nil {
+				log.Errorf("Failed to input password. Please try again.")
+				continue
+			}
+			defer zero.Bytes(passphrase)
+
+			var unlockAfter <-chan time.Time
+			err = w.Unlock(passphrase, unlockAfter)
+			if err != nil {
+				log.Errorf("Incorrect password entered. Please " +
+					"try again.")
+				continue
+			}
+
+			break
+		}
+	}
+}
+
 // rpcClientConnectLoop continuously attempts a connection to the consensus RPC
 // server.  When a connection is established, the client is used to sync the
 // loaded wallet, either immediately or when loaded at a later time.

wallet/addresspool.go

@@ -267,9 +267,42 @@ func (w *Wallet) CloseAddressPools() {
 	return
 }
 
+// CheckAddressPoolsInitialized checks to make sure an address pool exists
+// that that one can safely access functions and internal memory such as
+// mutexes.
+func (w *Wallet) CheckAddressPoolsInitialized(account uint32) error {
+	if w.addrPools[account] == nil {
+		return fmt.Errorf("Address pools for account %v "+
+			"are undeclared", account)
+	}
+	if w.addrPools[account].external == nil {
+		return fmt.Errorf("External address pool for "+
+			"account %v is undeclared", account)
+	}
+	if w.addrPools[account].internal == nil {
+		return fmt.Errorf("Internal address pool for "+
+			"account %v is undeclared", account)
+	}
+	if !w.addrPools[account].external.started {
+		return fmt.Errorf("External address pool for the "+
+			"account %v is uninitialized", account)
+	}
+	if !w.addrPools[account].internal.started {
+		return fmt.Errorf("Internal address pool for the "+
+			"account %v is uninitialized", account)
+	}
+
+	return nil
+}
+
 // GetNewAddressExternal is the exported function that gets a new external address
 // for the default account from the external address mempool.
 func (w *Wallet) GetNewAddressExternal() (dcrutil.Address, error) {
+	err := w.CheckAddressPoolsInitialized(waddrmgr.DefaultAccountNum)
+	if err != nil {
+		return nil, err
+	}
+
 	w.addrPools[waddrmgr.DefaultAccountNum].external.mutex.Lock()
 	defer w.addrPools[waddrmgr.DefaultAccountNum].external.mutex.Unlock()
 	address, err :=
@@ -283,6 +316,11 @@ func (w *Wallet) GetNewAddressExternal() (dcrutil.Address, error) {
 // GetNewAddressInternal is the exported function that gets a new internal address
 // for the default account from the internal address mempool.
 func (w *Wallet) GetNewAddressInternal() (dcrutil.Address, error) {
+	err := w.CheckAddressPoolsInitialized(waddrmgr.DefaultAccountNum)
+	if err != nil {
+		return nil, err
+	}
+
 	w.addrPools[waddrmgr.DefaultAccountNum].internal.mutex.Lock()
 	defer w.addrPools[waddrmgr.DefaultAccountNum].internal.mutex.Unlock()
 	address, err :=
@@ -296,6 +334,11 @@ func (w *Wallet) GetNewAddressInternal() (dcrutil.Address, error) {
 // NewAddress returns the next external chained address for a wallet given some
 // account.
 func (w *Wallet) NewAddress(account uint32) (dcrutil.Address, error) {
+	err := w.CheckAddressPoolsInitialized(account)
+	if err != nil {
+		return nil, err
+	}
+
 	// Get next address from wallet.
 	addr, err := w.addrPools[account].external.GetNewAddress()
 	if err != nil {
@@ -328,6 +371,11 @@ func (w *Wallet) NewAddress(account uint32) (dcrutil.Address, error) {
 
 // NewChangeAddress returns a new change address for a wallet.
 func (w *Wallet) NewChangeAddress(account uint32) (dcrutil.Address, error) {
+	err := w.CheckAddressPoolsInitialized(account)
+	if err != nil {
+		return nil, err
+	}
+
 	// Get next chained change address from wallet for account.
 	addr, err := w.addrPools[account].internal.GetNewAddress()
 	if err != nil {