Add change-pin command + better error handling with invalid PIN

README.md

@@ -2,16 +2,20 @@ This is a simple TOTP _(Time-based One-time Password)_ CLI tool. You can manage
 accounts with namespaces and protect your data with a PIN _(aka password)_.
 
 ```
-❯ ./bin/totp-cli
+❯ totp-cli
+              delete     Delete an account or a whole namespace
+                         `totp-cli delete nsname`
+                         `totp-cli delete nsname.accname`
+          change-pin     Change PIN code
+            generate     Generate a specific OTP
+                         `totp-cli generate namespace.account`
+                help     This help message :)
            add-token     Add new token
                          `totp-cli add-token`
                          This command will ask for the namespace, the account and the token
                 list     List all available namespaces or accounts under a namespace
                          `totp-cli list`      => list all namespaces
                          `totp-cli list myns` => list all accounts under 'myns' namespace
-            generate     Generate a specific OTP
-                         `totp-cli generate namespace.account`
-                help     This help message :)
 ```
 
 TODO: Documentation :D

commands.go

@@ -14,23 +14,25 @@ type CommandFunction func()
 var storage *Storage
 
 var commandHandlers map[string]CommandFunction = map[string]CommandFunction{
-	"generate":  Command_Generate,
-	"help":      Command_Help,
-	"add-token": Command_AddToken,
-	"list":      Command_List,
-	"delete":    Command_Delete,
+	"generate":   Command_Generate,
+	"help":       Command_Help,
+	"add-token":  Command_AddToken,
+	"list":       Command_List,
+	"delete":     Command_Delete,
+	"change-pin": Command_ChangePIN,
 }
 
 var commandDescriptions map[string]string = map[string]string{
-	"generate":  "Generate a specific OTP%NLWI%`totp-cli generate namespace.account`",
-	"help":      "This help message :)",
-	"add-token": "Add new token%NLWI%`totp-cli add-token`%NLWI%This command will ask for the namespace, the account and the token",
-	"list":      "List all available namespaces or accounts under a namespace%NLWI%`totp-cli list`      => list all namespaces%NLWI%`totp-cli list myns` => list all accounts under 'myns' namespace",
-	"delete":    "Delete an account or a whole namespace%NLWI%`totp-cli delete nsname`%NLWI%`totp-cli delete nsname.accname`",
+	"generate":   "Generate a specific OTP%NLWI%`totp-cli generate namespace.account`",
+	"help":       "This help message :)",
+	"add-token":  "Add new token%NLWI%`totp-cli add-token`%NLWI%This command will ask for the namespace, the account and the token",
+	"list":       "List all available namespaces or accounts under a namespace%NLWI%`totp-cli list`      => list all namespaces%NLWI%`totp-cli list myns` => list all accounts under 'myns' namespace",
+	"delete":     "Delete an account or a whole namespace%NLWI%`totp-cli delete nsname`%NLWI%`totp-cli delete nsname.accname`",
+	"change-pin": "Change PIN code",
 }
 
 func prepareStorage() {
-	pin := AskPIN(32)
+	pin := AskPIN(32, "")
 
 	currentUser, err := user.Current()
 	check(err)
@@ -127,7 +129,7 @@ func Command_AddToken() {
 
 	account = &Account{Name: accName, Token: token}
 
-	namespace.Accounts = []*Account{account}
+	namespace.Accounts = append(namespace.Accounts, account)
 
 	storage.Save()
 }
@@ -183,11 +185,27 @@ func Command_Delete() {
 	}
 }
 
+func Command_ChangePIN() {
+	prepareStorage()
+	newPIN := AskPIN(32, "New PIN")
+	newPINConfirm := AskPIN(32, "Again")
+
+	if !CheckPINConfirm(newPIN, newPINConfirm) {
+		fmt.Println("New PIN and the confirm mismatch!")
+		return
+	}
+
+	storage.PIN = newPIN
+	storage.Save()
+}
+
 func Command_NotImplementedYet() {
 	fmt.Println(" -- Not Implemented Yet --")
 }
 
 func askForAddTokenDetails() (namespace, account, token string) {
+	namespace = flag.Arg(1)
+	account = flag.Arg(2)
 	for len(namespace) < 1 {
 		namespace = Ask("Namespace")
 	}

storage.go

@@ -8,8 +8,10 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io"
 	"io/ioutil"
+	"os"
 )
 
 type Storage struct {
@@ -94,7 +96,10 @@ func (s *Storage) parse(decodedData []byte) {
 	}
 
 	err := json.Unmarshal(decodedData, &parsedData)
-	check(err)
+	if err != nil {
+		fmt.Println("Something went wrong. Maybe this PIN is not a valid one.")
+		os.Exit(1)
+	}
 
 	var namespaces []*Namespace
 

utils.go

@@ -12,18 +12,24 @@ import (
 
 func check(err error) {
 	if err != nil {
-		panic(err)
+		fmt.Println(err.Error())
+		os.Exit(1)
 	}
 }
 
-func AskPIN(length int) []byte {
+func AskPIN(length int, prompt string) []byte {
 	var pin []byte = make([]byte, length, length)
 	var text string
 
+	if prompt == "" {
+		prompt = "PIN"
+	}
+
 	text = os.Getenv("PIN")
 
 	if len(text) < 1 {
-		os.Stderr.Write([]byte("PIN: "))
+		prompt = fmt.Sprintf("%s: ", prompt)
+		os.Stderr.Write([]byte(prompt))
 		stdin := int(os.Stdin.Fd())
 		if terminal.IsTerminal(stdin) {
 			var lineBytes []byte
@@ -66,3 +72,25 @@ func Confirm(prompt string) bool {
 
 	return (text == "y" || text == "yes" || text == "sure")
 }
+
+func CheckPINConfirm(pin, confirm []byte) bool {
+	if pin == nil && confirm == nil {
+		return true
+	}
+
+	if pin == nil || confirm == nil {
+		return false
+	}
+
+	if len(pin) != len(confirm) {
+		return false
+	}
+
+	for i := range pin {
+		if pin[i] != confirm[i] {
+			return false
+		}
+	}
+
+	return true
+}