Initial commit

pkg/auth/password.go

@@ -0,0 +1,74 @@
+package auth
+
+import (
+	"addrss/pkg/repo"
+	"fmt"
+	"math/rand"
+	"time"
+
+	"golang.org/x/crypto/bcrypt"
+)
+
+type NewPassword struct {
+	Password string `json:"-"`
+	Hash     string `json:"-"`
+}
+
+type PasswordChange struct {
+	UserId          int64  `json:"userId"`
+	OldPassword     string `json:"oldPassword"`
+	NewPassword     string `json:"newPassword"`
+	ConfirmPassword string `json:"confirmPassword"`
+}
+
+func ChangePassword(pc PasswordChange) error {
+	u, err := repo.GetUserById(pc.UserId)
+	if err != nil {
+		return fmt.Errorf("could not get user for user id %d: %v", pc.UserId, err)
+	}
+
+	if err = bcrypt.CompareHashAndPassword([]byte(u.Password), []byte(pc.OldPassword)); err != nil {
+		return fmt.Errorf("incorrect password for user id %d", pc.UserId)
+	}
+
+	h, err := bcrypt.GenerateFromPassword([]byte(pc.NewPassword), bcrypt.DefaultCost)
+	if err != nil {
+		return fmt.Errorf("bcrypt error: %v", err)
+	}
+
+	u.Password = string(h)
+	if err = repo.UpdateUserPassword(u); err != nil {
+		return fmt.Errorf("failed to update password for user id %d: %v", u.Id, err)
+	}
+
+	return nil
+}
+
+func GetRandomPassword(length int) (NewPassword, error) {
+	p := GetRandomString(length)
+
+	h, err := bcrypt.GenerateFromPassword([]byte(p), bcrypt.DefaultCost)
+	if err != nil {
+		return NewPassword{}, err
+	}
+
+	np := NewPassword{
+		Password: p,
+		Hash:     string(h),
+	}
+
+	return np, nil
+}
+
+// GetRandomString Keep as a separate function in case this becomes useful for some other purpose
+func GetRandomString(length int) string {
+	const chars = "!@#$%?abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	rnd := rand.New(rand.NewSource(time.Now().UnixNano()))
+
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = chars[rnd.Intn(len(chars))]
+	}
+
+	return string(b)
+}