Harden scan robustness and tests

plugins/services/text_protocol.go

@@ -0,0 +1,54 @@
+//go:build !plugin_selective || plugin_activemq || plugin_imap || plugin_pop3 || plugin_redis
+
+package services
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func hasLineBreak(s string) bool {
+	return strings.ContainsAny(s, "\r\n")
+}
+
+func rejectLineBreaks(values ...string) error {
+	for _, value := range values {
+		if hasLineBreak(value) {
+			return fmt.Errorf("credential contains line break")
+		}
+	}
+	return nil
+}
+
+func imapQuotedString(s string) (string, error) {
+	if hasLineBreak(s) {
+		return "", fmt.Errorf("imap credential contains line break")
+	}
+	return strconv.Quote(s), nil
+}
+
+func buildIMAPLoginCommand(tag, username, password string) (string, error) {
+	quotedUser, err := imapQuotedString(username)
+	if err != nil {
+		return "", err
+	}
+	quotedPass, err := imapQuotedString(password)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%s LOGIN %s %s\r\n", tag, quotedUser, quotedPass), nil
+}
+
+func buildRedisAuthCommand(password string) []byte {
+	return buildRedisCommand("AUTH", password)
+}
+
+func buildRedisCommand(args ...string) []byte {
+	var b strings.Builder
+	_, _ = fmt.Fprintf(&b, "*%d\r\n", len(args))
+	for _, arg := range args {
+		_, _ = fmt.Fprintf(&b, "$%d\r\n%s\r\n", len(arg), arg)
+	}
+	return []byte(b.String())
+}