Harden scan robustness and tests

plugins/services/redis_test.go

@@ -0,0 +1,34 @@
+//go:build plugin_redis || !plugin_selective
+
+package services
+
+import (
+	"net"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestRedisReadReplyIsBounded(t *testing.T) {
+	conn := &redisReplyTestConn{Reader: strings.NewReader(strings.Repeat("a", maxRedisReplyBytes+1024))}
+
+	got, err := NewRedisPlugin().readReply(conn)
+	if err != nil {
+		t.Fatalf("readReply() error = %v", err)
+	}
+	if len(got) != maxRedisReplyBytes {
+		t.Fatalf("readReply() len = %d, want %d", len(got), maxRedisReplyBytes)
+	}
+}
+
+type redisReplyTestConn struct {
+	*strings.Reader
+}
+
+func (c *redisReplyTestConn) Write([]byte) (int, error)        { return 0, nil }
+func (c *redisReplyTestConn) Close() error                     { return nil }
+func (c *redisReplyTestConn) LocalAddr() net.Addr              { return nil }
+func (c *redisReplyTestConn) RemoteAddr() net.Addr             { return nil }
+func (c *redisReplyTestConn) SetDeadline(time.Time) error      { return nil }
+func (c *redisReplyTestConn) SetReadDeadline(time.Time) error  { return nil }
+func (c *redisReplyTestConn) SetWriteDeadline(time.Time) error { return nil }