Diff: net/tcp.h

Revision:

0:d494b853ce97

Child:

2:e8e09adc41fc

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/net/tcp.h	Tue Oct 12 05:32:59 2010 +0000
@@ -0,0 +1,76 @@
+#ifndef TCP_H
+#define TCP_H
+
+#include "net.h"
+
+#define IPPROTO_TCP 0x06
+typedef struct {
+  u16 source_port;
+  u16 destination_port;
+  u32 sequence_number;
+  u32 acknowledge_number;
+  
+  unsigned data_offset_bytes_div4:4;
+  unsigned unused_0:4;
+  
+  unsigned fin:1; // connection FINished (no more data from sender)
+  unsigned syn:1; // SYNchronize sequence numbers
+  unsigned rst:1; // ReSeT the connection
+  unsigned psh:1; // PuSH to receiving application
+  unsigned ack:1; // ACKnowledge fiend is significant
+  unsigned urg:1; // URGent field is significant
+  unsigned ece:1; // ECn Echo
+  unsigned cwr:1; // Congestion Window Reduced
+  
+  u16 window_size;
+  u16 checksum;
+  u16 urgent_pointer;
+  // Options (unsupported)
+  unsigned char data[];
+} TCP_SegmentHeader;
+
+inline void fix_endian_tcp(TCP_SegmentHeader *segment)
+{
+  segment->unused_0 ^= segment->data_offset_bytes_div4;
+  segment->data_offset_bytes_div4 ^= segment->unused_0;
+  segment->unused_0 ^= segment->data_offset_bytes_div4;
+  fix_endian_u16(&segment->source_port);
+  fix_endian_u16(&segment->destination_port);
+  fix_endian_u16(&segment->window_size);
+  // No fixing checksums
+  fix_endian_u16(&segment->urgent_pointer);
+  fix_endian_u32(&segment->sequence_number);
+  fix_endian_u32(&segment->acknowledge_number);
+}
+
+inline void print_tcp(TCP_SegmentHeader *segment)
+{
+  main_log.printf("TCP Segment:");
+  main_log.printf("  Source:    PORT %d", segment->source_port);
+  main_log.printf("  Dest:      PORT %d", segment->destination_port);
+  main_log.printf("  TCP Seqno: 0x%08X", segment->sequence_number);
+  main_log.printf("  TCP Ackno: 0x%08X", segment->acknowledge_number);
+  main_log.printf("  Header:    %d bytes", segment->data_offset_bytes_div4*4);
+  if (segment->cwr) main_log.printf("  Flag:      CWR");
+  if (segment->ece) main_log.printf("  Flag:      ECE");
+  if (segment->urg) main_log.printf("  Flag:      URG");
+  if (segment->ack) main_log.printf("  Flag:      ACK");
+  if (segment->psh) main_log.printf("  Flag:      PSH");
+  if (segment->rst) main_log.printf("  Flag:      RST");
+  if (segment->syn) main_log.printf("  Flag:      SYN");
+  if (segment->fin) main_log.printf("  Flag:      FIN");
+}
+
+inline u16 pseudo_header_checksum(IP_Address source, IP_Address destination, u16 length)
+{
+  struct {
+    IP_Address src, dst;
+    u8 zeros;
+    u8 proto;
+    u16 length;
+  } pseudoheader = {source, destination, 0, IPPROTO_TCP, length};
+  fix_endian_u16(&pseudoheader.length);
+  return checksum(&pseudoheader, sizeof(pseudoheader));
+}
+
+#endif
\ No newline at end of file