#ifndef _IPT_AH_H#define _IPT_AH_Hstructipt_ah{u_int32_tspis[2];/* Security Parameter Index */u_int8_tinvflags;/* Inverse flags */};/* Values for "invflags" field in struct ipt_ah. */#define IPT_AH_INV_SPI 0x01 /* Invert the sense of spi. */#define IPT_AH_INV_MASK 0x01 /* All possible flags. */#endif /*_IPT_AH_H*/