From 0939068492b5286a2e2bfe838cb54d760e7bcbd9 Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Thu, 12 Sep 2024 00:00:50 -0400
Subject: [PATCH] chore(connlib): report UDP socket buffer sizes (#6564)

The actual size of the send and receive buffers is OS-dependent. To aid
debugging with customer-submitted logs, we now print the size of the
send and receive buffers of each UDP socket.
---
 rust/socket-factory/src/lib.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/rust/socket-factory/src/lib.rs b/rust/socket-factory/src/lib.rs
index ffdcbf053..c8ebd43f7 100644
--- a/rust/socket-factory/src/lib.rs
+++ b/rust/socket-factory/src/lib.rs
@@ -8,7 +8,6 @@ use std::{
     task::{ready, Context, Poll},
 };
 
-use socket2::SockAddr;
 use std::any::Any;
 use std::collections::hash_map::Entry;
 use std::pin::Pin;
@@ -32,8 +31,8 @@ pub fn tcp(addr: &SocketAddr) -> io::Result<TcpSocket> {
     })
 }
 
-pub fn udp(addr: &SocketAddr) -> io::Result<UdpSocket> {
-    let addr: SockAddr = (*addr).into();
+pub fn udp(std_addr: &SocketAddr) -> io::Result<UdpSocket> {
+    let addr = socket2::SockAddr::from(*std_addr);
     let socket = socket2::Socket::new(addr.domain(), socket2::Type::DGRAM, None)?;
 
     // Note: for AF_INET sockets IPV6_V6ONLY is not a valid flag
@@ -44,6 +43,11 @@ pub fn udp(addr: &SocketAddr) -> io::Result<UdpSocket> {
     socket.set_nonblocking(true)?;
     socket.bind(&addr)?;
 
+    let send_buf_size = socket.send_buffer_size()?;
+    let recv_buf_size = socket.recv_buffer_size()?;
+
+    tracing::info!(addr = %std_addr, %send_buf_size, %recv_buf_size, "Created new UDP socket");
+
     let socket = std::net::UdpSocket::from(socket);
     let socket = tokio::net::UdpSocket::try_from(socket)?;
     let socket = UdpSocket::new(socket)?;