MFA fix, added IP blacklist, update webmail client

internal/imapserver/server.go

@@ -2,13 +2,18 @@ package imapserver
 
 import (
 	"crypto/tls"
+	"net"
 
 	goimapserver "github.com/emersion/go-imap/v2/imapserver"
 )
 
 func newSessionFunc(backend *Backend) func(*goimapserver.Conn) (goimapserver.Session, *goimapserver.GreetingData, error) {
 	return func(c *goimapserver.Conn) (goimapserver.Session, *goimapserver.GreetingData, error) {
-		return backend.NewSession(), nil, nil
+		host, _, err := net.SplitHostPort(c.NetConn().RemoteAddr().String())
+		if err != nil {
+			host = c.NetConn().RemoteAddr().String()
+		}
+		return backend.NewSession(host), nil, nil
 	}
 }