1 files changed, 58 insertions, 0 deletions
diff --git a/internal/auth/smtp/config.go b/internal/auth/smtp/config.go
new file mode 100644
index 00000000..33985f45
--- /dev/null
+++ b/internal/auth/smtp/config.go
@@ -0,0 +1,58 @@
+// Copyright 2020 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package smtp
+
+import (
+	"crypto/tls"
+	"fmt"
+	"net/smtp"
+
+	"github.com/pkg/errors"
+)
+
+// Config contains configuration for SMTP authentication.
+//
+// ⚠️ WARNING: Change to the field name must preserve the INI key name for backward compatibility.
+type Config struct {
+	Auth           string
+	Host           string
+	Port           int
+	AllowedDomains string
+	TLS            bool `ini:"tls"`
+	SkipVerify     bool
+}
+
+func (c *Config) doAuth(auth smtp.Auth) error {
+	client, err := smtp.Dial(fmt.Sprintf("%s:%d", c.Host, c.Port))
+	if err != nil {
+		return err
+	}
+	defer client.Close()
+
+	if err = client.Hello("gogs"); err != nil {
+		return err
+	}
+
+	if c.TLS {
+		if ok, _ := client.Extension("STARTTLS"); ok {
+			if err = client.StartTLS(&tls.Config{
+				InsecureSkipVerify: c.SkipVerify,
+				ServerName:         c.Host,
+			}); err != nil {
+				return err
+			}
+		} else {
+			return errors.New("SMTP server does not support TLS")
+		}
+	}
+
+	if ok, _ := client.Extension("AUTH"); ok {
+		if err = client.Auth(auth); err != nil {
+			return err
+		}
+		return nil
+	}
+	return errors.New("unsupported SMTP authentication method")
+}