Line data    Source code

       1             : #ifndef HEADER_fd_src_util_net_headers_h
       2             : #define HEADER_fd_src_util_net_headers_h
       3             : 
       4             : #include "fd_udp.h"
       5             : #include "fd_eth.h"
       6             : 
       7             : /* fd_ip4_udp_hdrs is useful to construct Ethernet+IPv4+UDP network
       8             :    headers. Assumes that the IPv4 header has no options (IHL=5). */
       9             : 
      10             : union fd_ip4_udp_hdrs {
      11             :   uchar uc[ 42 ];
      12             :   struct {
      13             :     fd_eth_hdr_t eth[1];
      14             :     fd_ip4_hdr_t ip4[1];
      15             :     fd_udp_hdr_t udp[1];
      16             :   };
      17             : };
      18             : 
      19             : typedef union fd_ip4_udp_hdrs fd_ip4_udp_hdrs_t;
      20             : 
      21             : FD_PROTOTYPES_BEGIN
      22             : 
      23             : /* Helper method to populate a header template containing Ethernet,
      24             :    IPv4 (no options), and UDP headers.  Note that IPv4 and UDP header
      25             :    checksums are set to 0. */
      26             : 
      27             : static inline fd_ip4_udp_hdrs_t *
      28             : fd_ip4_udp_hdr_init( fd_ip4_udp_hdrs_t * hdrs,
      29             :                      ulong               payload_sz,
      30             :                      uint                src_ip,
      31           0 :                      ushort              src_port ) {
      32           0 :   fd_eth_hdr_t * eth = hdrs->eth;
      33           0 :   memset( eth->dst, 0, 6UL );
      34           0 :   memset( eth->src, 0, 6UL );
      35           0 :   eth->net_type  = fd_ushort_bswap( FD_ETH_HDR_TYPE_IP );
      36             : 
      37           0 :   fd_ip4_hdr_t * ip4 = hdrs->ip4;
      38           0 :   ip4->verihl       = FD_IP4_VERIHL( 4U, 5U );
      39           0 :   ip4->tos          = (uchar)0;
      40           0 :   ip4->net_tot_len  = fd_ushort_bswap( (ushort)(payload_sz + sizeof(fd_ip4_hdr_t)+sizeof(fd_udp_hdr_t)) );
      41           0 :   ip4->net_frag_off = fd_ushort_bswap( FD_IP4_HDR_FRAG_OFF_DF );
      42           0 :   ip4->ttl          = (uchar)64;
      43           0 :   ip4->protocol     = FD_IP4_HDR_PROTOCOL_UDP;
      44           0 :   ip4->check        = 0U;
      45           0 :   ip4->saddr        = src_ip;
      46           0 :   ip4->daddr        = 0;
      47             : 
      48           0 :   fd_udp_hdr_t * udp = hdrs->udp;
      49           0 :   udp->net_sport = fd_ushort_bswap( src_port );
      50           0 :   udp->net_dport = (ushort)0;
      51           0 :   udp->net_len   = fd_ushort_bswap( (ushort)(payload_sz + sizeof(fd_udp_hdr_t)) );
      52           0 :   udp->check     = (ushort)0;
      53             : 
      54           0 :   return hdrs;
      55           0 : }
      56             : 
      57             : FD_PROTOTYPES_END
      58             : 
      59             : union fd_ip4_port {
      60             :   struct {
      61             :     uint   addr;  /* net order */
      62             :     ushort port;  /* net order */
      63             :   };
      64             :   ulong l;
      65             : };
      66             : 
      67             : typedef union fd_ip4_port fd_ip4_port_t;
      68             : 
      69             : #endif /* HEADER_fd_src_util_net_headers_h */