✨ Offer password generation and query

cmd_tools.go

@@ -0,0 +1,66 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"math/rand"
+
+	pwgen "github.com/sethvargo/go-password/password"
+	"golang.org/x/crypto/bcrypt"
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+type PasswordParam struct {
+	Password               string `name:"password" help:"The password to be set. Empty to prompt."`
+	GeneratePassword       bool   `name:"generate-password" help:"If set, the password is auto generated."`
+	GeneratePasswordLength int    `name:"password-length" help:"If generate-password is set, this specified the length of the generated password." default:"32"`
+}
+
+func (p *PasswordParam) acquirePassword() (string, error) {
+	if p.GeneratePassword {
+		// math.rand is not secure. For determining the number of digits in a password
+		// it should suffice, though. Beware that we expect here that we at least initialized
+		// the seed somewhere.
+		pw, err := pwgen.Generate(p.GeneratePasswordLength, rand.Intn(p.GeneratePasswordLength/2), 0, false, true)
+		if err != nil {
+			return "", fmt.Errorf("cannot generate password: %w", err)
+		}
+
+		p.Password = pw
+
+		fmt.Printf("Password generated: %s\n", p.Password)
+	}
+
+	if p.Password == "" {
+		fmt.Printf("Enter password: ")
+		bytePassword, err := terminal.ReadPassword(0)
+		if err != nil {
+			fmt.Println()
+			return "", fmt.Errorf("error reading password: %w", err)
+		}
+		fmt.Printf("\nRepeat password: ")
+		bytePasswordRepeat, err := terminal.ReadPassword(0)
+		if err != nil {
+			fmt.Println()
+			return "", fmt.Errorf("error reading password: %w", err)
+		}
+		fmt.Println()
+
+		if !bytes.Equal(bytePassword, bytePasswordRepeat) {
+			return "", fmt.Errorf("passwords do not match")
+		}
+
+		p.Password = string(bytePassword)
+	}
+
+	if p.Password == "" {
+		return "", fmt.Errorf("empty password supplied")
+	}
+
+	hash, err := bcrypt.GenerateFromPassword([]byte(p.Password), 0)
+	if err != nil {
+		return "", fmt.Errorf("cannot hash password: %w", err)
+	}
+
+	return string(hash), nil
+}

cmd_user.go

@@ -53,9 +53,9 @@ func (cmd CmdUserList) Run(app *app) error {
 }
 
 type CmdUserAdd struct {
-	Username string     `arg:"" name:"username" help:"The username to be added."`
-	Password string     `name:"password" help:"The password of the new user."`
-	Role     GlobalRole `name:"role" default:"user" help:"Role of the user. 'admin' or ' user'"`
+	Username string `arg:"" name:"username" help:"The username to be added."`
+	PasswordParam
+	Role GlobalRole `name:"role" default:"user" help:"Role of the user. 'admin' or ' user'"`
 }
 
 func (cmd CmdUserAdd) Run(app *app) error {
@@ -66,14 +66,14 @@ func (cmd CmdUserAdd) Run(app *app) error {
 		return fmt.Errorf("invalid user role")
 	}
 
-	hash, err := bcrypt.GenerateFromPassword([]byte(cmd.Password), 0)
+	password, err := cmd.acquirePassword()
 	if err != nil {
-		return fmt.Errorf("cannot hash password: %w", err)
+		return fmt.Errorf("cannot acquire password for user: %w", err)
 	}
 
 	user := User{
 		Username: cmd.Username,
-		Password: string(hash),
+		Password: password,
 		Role:     cmd.Role,
 	}
 	return app.userStore.AddUser(user)

main.go

@@ -26,6 +26,11 @@
 package main
 
 import (
+	crand "crypto/rand"
+	"math"
+	"math/big"
+	"math/rand"
+
 	"github.com/alecthomas/kong"
 )
 
@@ -38,6 +43,14 @@ type app struct {
 }
 
 func main() {
+	// When we need simple randomization (not cryptographically secure one), we should at least start
+	// with some non-default-seed.
+	seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
+	if err != nil {
+		panic("cannot initialize rand: " + err.Error())
+	}
+	rand.Seed(seed.Int64())
+
 	var app app
 	ctx := kong.Parse(&app)
 
@@ -50,32 +63,6 @@ func main() {
 
 	ctx.FatalIfErrorf(ctx.Run(&app))
 
-	//if *genPassword {
-	//	// math.rand is not secure. For determining the number of digits in a password
-	//	// it should suffice, though.
-	//	rand.Seed(time.Now().UnixNano())
-	//	pwLen := 32
-	//	pw, err := pwgen.Generate(pwLen, rand.Intn(pwLen/2), 0, false, true)
-	//	if err != nil {
-	//		panic(err)
-	//	}
-	//	hash, err := bcrypt.GenerateFromPassword([]byte(pw), 0)
-	//	if err != nil {
-	//		panic(err)
-	//	}
-	//
-	//	fmt.Printf("Password: %s\n", pw)
-	//	fmt.Printf("    Hash: %s\n", hash)
-	//	return
-	//} else if *hashPassword != "" {
-	//	hash, err := bcrypt.GenerateFromPassword([]byte(*hashPassword), 0)
-	//	if err != nil {
-	//		panic(err)
-	//	}
-	//	fmt.Println(string(hash))
-	//	return
-	//}
-
 	//c := LoadConfig(*configFile)
 	//
 	//h := &webdav.Handler{}