#ifndef VJBSDHDR_H #define VJBSDHDR_H #include "lwip/tcp.h" /* * Structure of an internet header, naked of options. * * We declare ip_len and ip_off to be short, rather than u_short * pragmatically since otherwise unsigned comparisons can result * against negative integers quite easily, and fail in subtle ways. */ PACK_STRUCT_BEGIN struct ip { #if defined(NO_CHAR_BITFIELDS) u_char ip_hl_v; // bug in GCC for mips means the bitfield stuff will sometimes break - so we use a char for both and get round it with macro's instead... #else #if BYTE_ORDER == LITTLE_ENDIAN u_char ip_hl:4, /* header length */ ip_v:4; /* version */ #elif BYTE_ORDER == BIG_ENDIAN u_char ip_v:4, /* version */ ip_hl:4; /* header length */ #else COMPLAIN - NO BYTE ORDER SELECTED! #endif #endif u_char ip_tos; /* type of service */ u_short ip_len; /* total length */ u_short ip_id; /* identification */ u_short ip_off; /* fragment offset field */ #define IP_DF 0x4000 /* dont fragment flag */ #define IP_MF 0x2000 /* more fragments flag */ #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ u_char ip_ttl; /* time to live */ u_char ip_p; /* protocol */ u_short ip_sum; /* checksum */ struct in_addr ip_src,ip_dst; /* source and dest address */ }; PACK_STRUCT_END typedef u32_t tcp_seq; /* * TCP header. * Per RFC 793, September, 1981. */ PACK_STRUCT_BEGIN struct tcphdr { u_short th_sport; /* source port */ u_short th_dport; /* destination port */ tcp_seq th_seq; /* sequence number */ tcp_seq th_ack; /* acknowledgement number */ #if defined(NO_CHAR_BITFIELDS) u_char th_x2_off; #else #if BYTE_ORDER == LITTLE_ENDIAN u_char th_x2:4, /* (unused) */ th_off:4; /* data offset */ #endif #if BYTE_ORDER == BIG_ENDIAN u_char th_off:4, /* data offset */ th_x2:4; /* (unused) */ #endif #endif u_char th_flags; u_short th_win; /* window */ u_short th_sum; /* checksum */ u_short th_urp; /* urgent pointer */ }; PACK_STRUCT_END #endif /* VJBSDHDR_H */