Line data    Source code

       1             : /* fd_udpecho_tile mirrors incoming UDP packets back to the source.
       2             :    Useful for testing connectivity issues, but somewhat dangerous to run
       3             :    in prod on the Internet. */
       4             : 
       5             : #include "../../../../disco/topo/fd_topo.h"
       6             : 
       7             : struct fd_udpecho_tile_ctx {
       8             :   void * in_base;
       9             :   void * out_base;
      10             :   ulong  chunk0;
      11             :   ulong  wmark;
      12             :   ulong  chunk;
      13             :   ulong  pkt_sz;
      14             :   uint   ip4_dst;
      15             : };
      16             : 
      17             : typedef struct fd_udpecho_tile_ctx fd_udpecho_tile_ctx_t;
      18             : 
      19             : FD_FN_CONST static inline ulong
      20           0 : scratch_align( void ) {
      21           0 :   return alignof(fd_udpecho_tile_ctx_t);
      22           0 : }
      23             : 
      24             : FD_FN_PURE static inline ulong
      25           0 : scratch_footprint( fd_topo_tile_t const * tile FD_PARAM_UNUSED ) {
      26           0 :   return sizeof(fd_udpecho_tile_ctx_t);
      27           0 : }
      28             : 
      29             : static void
      30             : unprivileged_init( fd_topo_t *      topo,
      31           0 :                    fd_topo_tile_t * tile ) {
      32           0 :   fd_udpecho_tile_ctx_t * ctx = fd_topo_obj_laddr( topo, tile->tile_obj_id );
      33             : 
      34           0 :   FD_TEST( tile->out_cnt==1UL );
      35           0 :   void * out_base   = topo->workspaces[ topo->objs[ topo->links[ tile->out_link_id[ 0 ] ].dcache_obj_id ].wksp_id ].wksp;
      36           0 :   void * out_dcache = topo->links[ tile->out_link_id[ 0 ] ].dcache;
      37           0 :   ctx->out_base    = out_base;
      38           0 :   ctx->chunk0      = fd_dcache_compact_chunk0( out_base, out_dcache );
      39           0 :   ctx->wmark       = fd_dcache_compact_wmark( out_base, out_dcache, FD_NET_MTU );
      40           0 :   ctx->chunk       = ctx->chunk0;
      41             : 
      42           0 :   FD_TEST( tile->in_cnt==1UL );
      43           0 :   void * in_base = topo->workspaces[ topo->objs[ topo->links[ tile->in_link_id[ 0 ] ].dcache_obj_id ].wksp_id ].wksp;
      44           0 :   ctx->in_base = in_base;
      45           0 : }
      46             : 
      47             : static inline void
      48             : during_frag( fd_udpecho_tile_ctx_t * ctx,
      49             :              ulong                   in_idx FD_PARAM_UNUSED,
      50             :              ulong                   seq,
      51             :              ulong                   sig    FD_PARAM_UNUSED,
      52             :              ulong                   chunk,
      53             :              ulong                   sz,
      54           0 :              ulong                   ctl ) {
      55           0 :   FD_TEST( sz<=FD_NET_MTU );
      56           0 :   ctx->pkt_sz = 0;
      57             : 
      58           0 :   ulong const minsz = sizeof(fd_eth_hdr_t)+sizeof(fd_ip4_hdr_t)+sizeof(fd_udp_hdr_t);
      59           0 :   if( FD_UNLIKELY( sz<minsz ) ) return;
      60             : 
      61           0 :   uchar      * frame_out = /*           */fd_chunk_to_laddr      ( ctx->out_base, ctx->chunk );
      62           0 :   void const * frame_in  = (uchar const *)fd_chunk_to_laddr_const( ctx->in_base,  chunk ) + ctl;
      63             : 
      64           0 :   fd_eth_hdr_t const * eth_hdr_in = fd_type_pun_const( frame_in );
      65           0 :   if( FD_UNLIKELY( fd_ushort_bswap( eth_hdr_in->net_type )!=FD_ETH_HDR_TYPE_IP ) ) return;
      66             : 
      67           0 :   fd_ip4_hdr_t const * ip4_hdr_in = fd_type_pun_const( (eth_hdr_in+1) );
      68           0 :   if( FD_UNLIKELY( FD_IP4_GET_VERSION( *ip4_hdr_in )!=4 ) ) return;
      69           0 :   ulong ip4_len = FD_IP4_GET_LEN( *ip4_hdr_in );
      70           0 :   ulong ip4_sz  = fd_ushort_bswap( ip4_hdr_in->net_tot_len );
      71           0 :   sz = fd_ulong_min( sz, ip4_sz+sizeof(fd_eth_hdr_t) );
      72           0 :   if( FD_UNLIKELY( sz < sizeof(fd_eth_hdr_t)+ip4_len+sizeof(fd_udp_hdr_t) ) ) return;
      73           0 :   if( FD_UNLIKELY( ip4_hdr_in->protocol!=FD_IP4_HDR_PROTOCOL_UDP ) ) return;
      74             : 
      75           0 :   fd_udp_hdr_t const * udp_hdr_in = fd_type_pun_const( (ip4_hdr_in+1) );
      76           0 :   if( FD_UNLIKELY( fd_ushort_bswap( udp_hdr_in->net_len )<sizeof(fd_udp_hdr_t) ) ) return;
      77           0 :   ulong const udp_len = fd_ushort_bswap( udp_hdr_in->net_len );
      78           0 :   if( FD_UNLIKELY( udp_len<sizeof(fd_udp_hdr_t) ) ) return;
      79             : 
      80           0 :   void const * dgram_in = (udp_hdr_in+1);
      81           0 :   ulong const  dgram_sz = udp_len-sizeof(fd_udp_hdr_t);
      82           0 :   if( FD_UNLIKELY( (ulong)dgram_in+dgram_sz > (ulong)frame_in+sz ) ) return;
      83             : 
      84           0 :   fd_eth_hdr_t eth_hdr_out = {
      85           0 :     .net_type = fd_ushort_bswap( FD_ETH_HDR_TYPE_IP )
      86           0 :   };
      87           0 :   FD_STORE( fd_eth_hdr_t, frame_out, eth_hdr_out );
      88           0 :   fd_ip4_hdr_t ip4_hdr = {
      89           0 :     .verihl       = FD_IP4_VERIHL( 4, 5 ),
      90           0 :     .net_tot_len  = fd_ushort_bswap( (ushort)( 28+dgram_sz ) ),
      91           0 :     .net_id       = fd_ushort_bswap( (ushort)seq ),
      92           0 :     .net_frag_off = fd_ushort_bswap( FD_IP4_HDR_FRAG_OFF_DF ),
      93           0 :     .ttl          = 64,
      94           0 :     .protocol     = FD_IP4_HDR_PROTOCOL_UDP,
      95           0 :     .saddr        = ip4_hdr_in->daddr,
      96           0 :     .daddr        = ip4_hdr_in->saddr,
      97           0 :   };
      98           0 :   ip4_hdr.check = fd_ip4_hdr_check_fast( &ip4_hdr );
      99           0 :   ctx->ip4_dst = ip4_hdr.daddr;
     100           0 :   FD_STORE( fd_ip4_hdr_t, frame_out+14, ip4_hdr );
     101             : 
     102           0 :   fd_udp_hdr_t udp_hdr = {
     103           0 :     .net_sport = udp_hdr_in->net_dport,
     104           0 :     .net_dport = udp_hdr_in->net_sport,
     105           0 :     .net_len   = udp_hdr_in->net_len
     106           0 :   };
     107           0 :   FD_STORE( fd_udp_hdr_t, frame_out+34, udp_hdr );
     108             : 
     109           0 :   fd_memcpy( frame_out+42, dgram_in, dgram_sz );
     110           0 :   ctx->pkt_sz = 42+dgram_sz;
     111           0 : }
     112             : 
     113             : static inline void
     114             : after_frag( fd_udpecho_tile_ctx_t * ctx,
     115             :             ulong                   in_idx FD_PARAM_UNUSED,
     116             :             ulong                   in_seq FD_PARAM_UNUSED,
     117             :             ulong                   in_sig FD_PARAM_UNUSED,
     118             :             ulong                   in_sz  FD_PARAM_UNUSED,
     119             :             ulong                   in_tsorig,
     120             :             ulong                   in_tspub FD_PARAM_UNUSED,
     121           0 :             fd_stem_context_t *     stem ) {
     122           0 :   ulong out_sig   = fd_disco_netmux_sig( 0U, 0, ctx->ip4_dst, DST_PROTO_OUTGOING, 42 );
     123           0 :   ulong out_chunk = ctx->chunk;
     124           0 :   ulong out_sz    = ctx->pkt_sz;
     125           0 :   fd_stem_publish( stem, 0UL, out_sig, out_chunk, out_sz, 0, in_tsorig, 0UL );
     126           0 :   ctx->chunk = fd_dcache_compact_next( out_chunk, out_sz, ctx->chunk0, ctx->wmark );
     127           0 : }
     128             : 
     129           0 : #define STEM_BURST (1UL)
     130           0 : #define STEM_LAZY ((long)10e6)
     131             : 
     132           0 : #define STEM_CALLBACK_CONTEXT_TYPE fd_udpecho_tile_ctx_t
     133           0 : #define STEM_CALLBACK_CONTEXT_ALIGN alignof(fd_udpecho_tile_ctx_t)
     134             : 
     135           0 : #define STEM_CALLBACK_DURING_FRAG during_frag
     136           0 : #define STEM_CALLBACK_AFTER_FRAG  after_frag
     137             : 
     138             : #include "../../../../disco/stem/fd_stem.c"
     139             : 
     140             : fd_topo_run_tile_t fd_tile_udpecho = {
     141             :   .name              = "l4swap",
     142             :   .scratch_align     = scratch_align,
     143             :   .scratch_footprint = scratch_footprint,
     144             :   .unprivileged_init = unprivileged_init,
     145             :   .run               = stem_run
     146             : };