added network server files

[palacios.git] / misc / network_servers / vtl / test / vtl_ack.cc

diff --git a/misc/network_servers/vtl/test/vtl_ack.cc b/misc/network_servers/vtl/test/vtl_ack.cc
new file mode 100644 (file)
index 0000000..3e0d615
--- /dev/null
+++ b/misc/network_servers/vtl/test/vtl_ack.cc
@@ -0,0 +1,79 @@
+#include "vtl_ack.h"
+
+
+int make_ack_pkt(tcp_model_t * model, RawEthernetPacket * data_pkt, RawEthernetPacket * ack_pkt) {
+  unsigned long * seq_num_ptr ;
+  unsigned long seq_num = 0;
+  unsigned long rem_seq_num = 0;
+  unsigned long  payload_len = 0;
+  unsigned short tcp_hdr_len = 0;
+  unsigned long ack = 0;
+  unsigned long local_ts = 0;
+  unsigned short tcp_cksum = 0;
+  unsigned char ip_hdr_len = IP_HDR_LEN(pkt->data);
+  unsigned short ip_pkt_len = *(unsigned short *)(pkt->data + ETH_HDR_LEN + 2);
+  unsigned short ack_ip_pkt_len = *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + 2);
+  unsigned char ack_ip_hdr_len = IP_HDR_LEN(ack_pkt->data);
+
+  ip_pkt_len = ntohs(ip_pkt_len);
+  ack_ip_pkt_len = ntohs(ack_ip_pkt_len);
+
+  seq_num_ptr = (unsigned long *)(pkt->data + ETH_HDR_LEN + ip_hdr_len + 4);
+  seq_num = ntohl(*seq_num_ptr);
+  JRLDBG("Sequence Number = %lu\n", seq_num);
+
+  tcp_hdr_len = (*(pkt->data + ETH_HDR_LEN + ip_hdr_len + 12) & 0xf0) >> 2;
+
+  if (is_syn_pkt(pkt) == 1) {
+    ack = seq_num + 1;
+  } else {    
+    payload_len = ip_pkt_len  - (ip_hdr_len + tcp_hdr_len);
+    
+    JRLDBG("TCP Header Length = %hu\n", tcp_hdr_len);
+    JRLDBG("Payload Length = %lu\n", payload_len);
+    
+    ack = seq_num + payload_len;
+    JRLDBG("Ack Num = %lu\n", ack);
+  }
+
+  // Set IP id 
+  g_vtp_cons[vcon_i].ip_id--;
+  *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + 4) = htons(g_vtp_cons[vcon_i].ip_id);
+
+  // Recompute IP checksum
+  *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + 10) = 0;
+  *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + 10) = get_ip_checksum(ack_pkt);
+
+  //return 0;
+  // Set Sequence Number
+  rem_seq_num = htonl(g_vtp_cons[vcon_i].rem_seq_num);
+  *(unsigned long *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 4) = rem_seq_num;
+ 
+  // Set ACK Number
+  ack = htonl(ack);
+  *(unsigned long *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 8) = ack;
+
+  // Set TCP Timestamp option
+  local_ts = get_tcp_timestamp(pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 20, tcp_hdr_len - 20);
+
+  /* We use this for debugging:
+   * If the TCPDump trace shows timestamps with the value of '5' then they are our packets
+   */
+  
+  *(unsigned long *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 24) = g_vtp_cons[vcon_i].tcp_timestamp;
+  //*(unsigned long *)(ack_pkt->data + ETH_HDR_LEN + ip_hdr_len + 24) = htonl(5);
+
+
+  *(unsigned long *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 28) = local_ts;
+
+  // Zero TCP chksum
+  *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 16) = 0;
+
+  // Get TCP chksum
+  tcp_cksum = get_tcp_checksum(ack_pkt, ack_ip_pkt_len - ack_ip_hdr_len);
+
+  // Set TCP chksum
+  *(unsigned short *)(ack_pkt->data + ETH_HDR_LEN + ack_ip_hdr_len + 16) = tcp_cksum;
+
+
+}