maddy/internal/target/smtp/sasl.go
2025-09-05 16:54:41 +02:00

78 lines
2.8 KiB
Go

/*
Maddy Mail Server - Composable all-in-one email server.
Copyright © 2019-2020 Max Mazurov <fox.cpp@disroot.org>, Maddy Mail Server contributors
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package smtp_downstream
import (
"github.com/emersion/go-sasl"
"github.com/foxcpp/maddy/framework/config"
"github.com/foxcpp/maddy/framework/exterrors"
"github.com/foxcpp/maddy/framework/module"
)
type saslClientFactory = func(msgMeta *module.MsgMetadata) (sasl.Client, error)
// saslAuthDirective returns saslClientFactory function used to create sasl.Client.
// for use in outbound connections.
//
// Authentication information of the current client should be passed in arguments.
func saslAuthDirective(_ *config.Map, node config.Node) (interface{}, error) {
if len(node.Children) != 0 {
return nil, config.NodeErr(node, "can't declare a block here")
}
if len(node.Args) == 0 {
return nil, config.NodeErr(node, "at least one argument required")
}
switch node.Args[0] {
case "off":
return nil, nil
case "forward":
if len(node.Args) > 1 {
return nil, config.NodeErr(node, "no additional arguments required")
}
return func(msgMeta *module.MsgMetadata) (sasl.Client, error) {
if msgMeta.Conn == nil || msgMeta.Conn.AuthUser == "" || msgMeta.Conn.AuthPassword == "" {
return nil, &exterrors.SMTPError{
Code: 530,
EnhancedCode: exterrors.EnhancedCode{5, 7, 0},
Message: "Authentication is required",
TargetName: "target.smtp",
Reason: "Credentials forwarding is requested but the client is not authenticated",
}
}
return sasl.NewPlainClient("", msgMeta.Conn.AuthUser, msgMeta.Conn.AuthPassword), nil
}, nil
case "plain":
if len(node.Args) != 3 {
return nil, config.NodeErr(node, "two additional arguments are required (username, password)")
}
return func(*module.MsgMetadata) (sasl.Client, error) {
return sasl.NewPlainClient("", node.Args[1], node.Args[2]), nil
}, nil
case "external":
if len(node.Args) > 1 {
return nil, config.NodeErr(node, "no additional arguments required")
}
return func(*module.MsgMetadata) (sasl.Client, error) {
return sasl.NewExternalClient(""), nil
}, nil
default:
return nil, config.NodeErr(node, "unknown authentication mechanism: %s", node.Args[0])
}
}