Pong over ipv4 response

app/src/main.rs

@@ -35,8 +35,8 @@ impl<A: Address> ServersContext<A> for Servers2NetworkCtxTestImpl<A> {
         );
     }
 
-    fn report_ping(&mut self, addr: A, id: u64, ping_ms: u64) {
-        println!("{} {ping_ms}", addr.to_string())
+    fn report_ping(&mut self, addr: A, id: u64, ping_ms: u128) {
+        println!("{} {ping_ms} ms", addr.to_string())
     }
 
     fn report_error(&mut self, addr: A, id: u64) {

network/abstract/src/lib.rs

@@ -12,7 +12,7 @@ pub trait NetworkContext {
 pub trait ServersContext<A: Address> {
     fn start_measuring(&mut self) -> (u64, impl Iterator<Item = A>);
 
-    fn report_ping(&mut self, addr: A, id: u64, ping_ms: u64);
+    fn report_ping(&mut self, addr: A, id: u64, ping_ms: u128);
 
     fn report_error(&mut self, addr: A, id: u64);
 }

network/icmp/src/conversions.rs

@@ -0,0 +1,39 @@
+pub(crate) fn hton16(v: u16, b: &mut [u8]) {
+    b[0] = (v >> 8) as u8;
+    b[1] = (v & 0xFF) as u8;
+}
+
+pub(crate) fn hton64(v: u64, b: &mut [u8]) {
+    hton16((v >> 48) as u16, b);
+    hton16(((v >> 32) & 0xFFFF) as u16, &mut b[2..4]);
+    hton16(((v >> 16) & 0xFFFF) as u16, &mut b[4..6]);
+    hton16((v & 0xFFFF) as u16, &mut b[6..8]);
+}
+
+pub(crate) fn hton128(v: u128, b: &mut [u8]) {
+    hton64((v >> 64) as u64, b);
+    hton64((v & 0xFFFF_FFFF_FFFF_FFFF) as u64, &mut b[8..16]);
+}
+
+pub(crate) fn ntoh16(b: &[u8]) -> u16 {
+    let mut v = 0u16;
+    v += (b[0] as u16) << 8;
+    v += b[1] as u16;
+    return v;
+}
+
+pub(crate) fn ntoh64(b: &[u8]) -> u64 {
+    let mut v = 0u64;
+    v += (ntoh16(b) as u64) << 48;
+    v += (ntoh16(&b[2..4]) as u64) << 32;
+    v += (ntoh16(&b[4..6]) as u64) << 16;
+    v += ntoh16(&b[6..8]) as u64;
+    return v;
+}
+
+pub(crate) fn ntoh128(b: &[u8]) -> u128 {
+    let mut v = 0u128;
+    v += (ntoh64(b) as u128) << 64;
+    v += ntoh64(&b[8..16]) as u128;
+    return v;
+}

network/icmp/src/lib.rs

@@ -1,23 +1,9 @@
 mod checksum;
 mod ping;
+mod pong;
+mod conversions;
 
 use checksum::IPv4ChecksumAccumulator;
 
 pub use ping::fmt_icmp_echo_req;
-
-fn hton16(v: u16, b: &mut [u8]) {
-    b[0] = (v >> 8) as u8;
-    b[1] = (v & 0xFF) as u8;
-}
-
-fn hton64(v: u64, b: &mut [u8]) {
-    hton16((v >> 48) as u16, b);
-    hton16(((v >> 32) & 0xFFFF) as u16, &mut b[2..4]);
-    hton16(((v >> 16) & 0xFFFF) as u16, &mut b[4..6]);
-    hton16((v & 0xFFFF) as u16, &mut b[6..8]);
-}
-
-fn hton128(v: u128, b: &mut [u8]) {
-    hton64((v >> 64) as u64, b);
-    hton64((v & 0xFFFF_FFFF_FFFF_FFFF) as u64, &mut b[8..16]);
-}
+pub use pong::{parse_icmp_echo_res, IcmpPong};

network/icmp/src/ping.rs

@@ -1,5 +1,5 @@
 use crate::checksum::IPv4ChecksumAccumulator;
-use crate::{hton128, hton16, hton64};
+use crate::conversions::{hton128, hton16, hton64};
 
 pub fn fmt_icmp_echo_req(buff: &mut [u8], seq_no: u16, req_id: u64, timestamp: u128) -> usize{
     buff[0] = 8;

network/icmp/src/pong.rs

@@ -0,0 +1,24 @@
+use crate::checksum::IPv4ChecksumAccumulator;
+use crate::conversions::{hton16, hton64, hton128, ntoh16, ntoh64, ntoh128};
+
+pub enum IcmpPong {
+    WrongChecksum,
+    Success { req_id: u64, timestamp: u128 },
+}
+
+pub fn parse_icmp_echo_res(buff: &[u8]) -> IcmpPong {
+    let expected_checksum = ntoh16(&buff[2..4]);
+    let mut checksum = IPv4ChecksumAccumulator::new();
+    checksum.add_first_byte(buff[0]);
+    checksum.add_second_byte(buff[1]);
+    checksum.add_trailing_data(&buff[4..32]);
+    let actual_checksum = checksum.snapshot();
+    if actual_checksum != expected_checksum {
+        return IcmpPong::WrongChecksum;
+    }
+
+    return IcmpPong::Success {
+        req_id: ntoh64(&buff[8..16]),
+        timestamp: ntoh128(&buff[16..32]),
+    };
+}

network/windows/src/eventloop/mod.rs

@@ -12,10 +12,10 @@ use allocator::Allocator;
 use bgtu_networks_2_network_abstract::{Address, ServersContext};
 use std::ptr::NonNull;
 use std::time::{SystemTime, UNIX_EPOCH};
-use windows::Win32::Networking::WinSock::{WSAEACCES, WSA_ERROR};
+use windows::Win32::Networking::WinSock::{AF_INET, AF_INET6, WSAEACCES, WSA_ERROR};
 use windows::Win32::System::SystemInformation::GetTickCount;
 use windows::Win32::System::Threading::SleepEx;
-use bgtu_networks_2_network_icmp::fmt_icmp_echo_req;
+use bgtu_networks_2_network_icmp::{fmt_icmp_echo_req, parse_icmp_echo_res, IcmpPong};
 
 pub unsafe fn run_eventloop<Ctx: ServersContext<WindowsAddressKnown>>(ctx: *mut Ctx) {
     let heap = Allocator::new();
@@ -86,6 +86,29 @@ impl<'s, Ctx: ServersContext<WindowsAddressKnown>> RecvCallback<'_, Ctx> {
         unsafe {
             let this = this_ptr.cast::<Self>().as_ref();
             this.bind_callback();
+
+            let buffer_no_ip_header;
+            match addr.any.native.ss_family {
+                AF_INET => {
+                    let ipv4_len = ((buffer[0] & 0x0F) as usize) * 4;
+                    buffer_no_ip_header = &buffer[ipv4_len..buffer.len()];
+                }
+                AF_INET6 => {
+                    buffer_no_ip_header = &buffer[40..buffer.len()];
+                    // todo extra headers
+                }
+                _ => panic!("Unsupported L4 header")
+            }
+
+            match parse_icmp_echo_res(buffer_no_ip_header) {
+                IcmpPong::WrongChecksum => {
+                    println!("Wrong checksum")
+                }
+                IcmpPong::Success { req_id, timestamp } => {
+                    let delta = get_timestamp() - timestamp;
+                    NonNull::new_unchecked(this.ctx).as_mut().report_ping(addr, req_id, delta);
+                }
+            }
         }
 
         println!("Received from addr {} data {:02X?}", addr.to_string(), buffer);