3 files changed, 142 insertions, 0 deletions

diff --git a/services/auth/source/db/assert_interface_test.go b/services/auth/source/db/assert_interface_test.go
new file mode 100644
index 0000000..62387c7
--- /dev/null
+++ b/services/auth/source/db/assert_interface_test.go
@@ -0,0 +1,20 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db_test
+
+import (
+	auth_model "code.gitea.io/gitea/models/auth"
+	"code.gitea.io/gitea/services/auth"
+	"code.gitea.io/gitea/services/auth/source/db"
+)
+
+// This test file exists to assert that our Source exposes the interfaces that we expect
+// It tightly binds the interfaces and implementation without breaking go import cycles
+
+type sourceInterface interface {
+	auth.PasswordAuthenticator
+	auth_model.Config
+}
+
+var _ (sourceInterface) = &db.Source{}
diff --git a/services/auth/source/db/authenticate.go b/services/auth/source/db/authenticate.go
new file mode 100644
index 0000000..8160141
--- /dev/null
+++ b/services/auth/source/db/authenticate.go
@@ -0,0 +1,87 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db
+
+import (
+	"context"
+	"fmt"
+
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
+)
+
+// ErrUserPasswordNotSet represents a "ErrUserPasswordNotSet" kind of error.
+type ErrUserPasswordNotSet struct {
+	UID  int64
+	Name string
+}
+
+func (err ErrUserPasswordNotSet) Error() string {
+	return fmt.Sprintf("user's password isn't set [uid: %d, name: %s]", err.UID, err.Name)
+}
+
+// Unwrap unwraps this error as a ErrInvalidArgument error
+func (err ErrUserPasswordNotSet) Unwrap() error {
+	return util.ErrInvalidArgument
+}
+
+// ErrUserPasswordInvalid represents a "ErrUserPasswordInvalid" kind of error.
+type ErrUserPasswordInvalid struct {
+	UID  int64
+	Name string
+}
+
+func (err ErrUserPasswordInvalid) Error() string {
+	return fmt.Sprintf("user's password is invalid [uid: %d, name: %s]", err.UID, err.Name)
+}
+
+// Unwrap unwraps this error as a ErrInvalidArgument error
+func (err ErrUserPasswordInvalid) Unwrap() error {
+	return util.ErrInvalidArgument
+}
+
+// Authenticate authenticates the provided user against the DB
+func Authenticate(ctx context.Context, user *user_model.User, login, password string) (*user_model.User, error) {
+	if user == nil {
+		return nil, user_model.ErrUserNotExist{Name: login}
+	}
+
+	if !user.IsPasswordSet() {
+		return nil, ErrUserPasswordNotSet{UID: user.ID, Name: user.Name}
+	} else if !user.ValidatePassword(password) {
+		return nil, ErrUserPasswordInvalid{UID: user.ID, Name: user.Name}
+	}
+
+	// Update password hash if server password hash algorithm have changed
+	// Or update the password when the salt length doesn't match the current
+	// recommended salt length, this in order to migrate user's salts to a more secure salt.
+	if user.PasswdHashAlgo != setting.PasswordHashAlgo || len(user.Salt) != user_model.SaltByteLength*2 {
+		if err := user.SetPassword(password); err != nil {
+			return nil, err
+		}
+		if err := user_model.UpdateUserCols(ctx, user, "passwd", "passwd_hash_algo", "salt"); err != nil {
+			return nil, err
+		}
+	}
+
+	// WARN: DON'T check user.IsActive, that will be checked on reqSign so that
+	// user could be hinted to resend confirm email.
+	if user.ProhibitLogin {
+		return nil, user_model.ErrUserProhibitLogin{
+			UID:  user.ID,
+			Name: user.Name,
+		}
+	}
+
+	// attempting to login as a non-user account
+	if user.Type != user_model.UserTypeIndividual {
+		return nil, user_model.ErrUserProhibitLogin{
+			UID:  user.ID,
+			Name: user.Name,
+		}
+	}
+
+	return user, nil
+}
diff --git a/services/auth/source/db/source.go b/services/auth/source/db/source.go
new file mode 100644
index 0000000..bb2270c
--- /dev/null
+++ b/services/auth/source/db/source.go
@@ -0,0 +1,35 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db
+
+import (
+	"context"
+
+	"code.gitea.io/gitea/models/auth"
+	user_model "code.gitea.io/gitea/models/user"
+)
+
+// Source is a password authentication service
+type Source struct{}
+
+// FromDB fills up an OAuth2Config from serialized format.
+func (source *Source) FromDB(bs []byte) error {
+	return nil
+}
+
+// ToDB exports the config to a byte slice to be saved into database (this method is just dummy and does nothing for DB source)
+func (source *Source) ToDB() ([]byte, error) {
+	return nil, nil
+}
+
+// Authenticate queries if login/password is valid against the PAM,
+// and create a local user if success when enabled.
+func (source *Source) Authenticate(ctx context.Context, user *user_model.User, login, password string) (*user_model.User, error) {
+	return Authenticate(ctx, user, login, password)
+}
+
+func init() {
+	auth.RegisterTypeConfig(auth.NoType, &Source{})
+	auth.RegisterTypeConfig(auth.Plain, &Source{})
+}