Fix slow exchanges on linux by adding polling and other improvements (#14)

* add prints to investigate slowness

* add loop sleep for blocking Stack

* add connection close http attribute and detect end of HTML page

* add timeout to bridge read

* examples/xnet: add ntp timestamp to prints and show output in readme

* add polling to http tap interface

* more digits in ntp format

* prevent crashes on non-8 timestamp
This commit is contained in:
Pat Whittingslow
2026-01-01 09:35:35 -03:00
committed by GitHub
parent 3cbef6fa92
commit f8166aea05
9 changed files with 297 additions and 36 deletions
+76 -1
View File
@@ -100,5 +100,80 @@ Now run the application you wish to test without elevated privilidges. Stackbasi
go run ./examples/stackbasic
```
**Wireshark**: Using the provided method of interfacing mean's you'll always be able to easily reach the TAP interface on your machine over HTTP from any process, be it Python or Go. To visualize the packets over the interface we suggest using wireshark and selecting the `tap0` interface which will show all activity over the HTTP TAP interface created with [`./examples/tap`](./examples/tap/main.go).
### Wireshark and Packet Capture API
Using the provided method of interfacing mean's you'll always be able to easily reach the TAP interface on your machine over HTTP from any process, be it Python or Go. To visualize the packets over the interface we suggest using **Wireshark** and selecting the `tap0` interface which will show all activity over the HTTP TAP interface created with [`./examples/tap`](./examples/tap/main.go).
Alternatively there's the [`internet/pcap`](./internet/pcap) package that does the same thing as Wireshark but as a Go API. Here's the result of running xnet example with pcap logging:
```log
go run ./examples/xnet -httpget -host google.com -ihttp -ntp
softrand 1767229198
NIC hardware address: d8:5e:d3:43:03:eb bridgeHW: d8:5e:d3:43:03:eb mtu: 1500 addr: 192.168.1.53/24
OUT 328 [Ethernet len=14; destination=ff:ff:ff:ff:ff:ff; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=255.255.255.255 | UDP [RFC768] len=8; (Source port)=68; (Destination port)=67 | DHCPv4 len=285; op=1; Flags=0x0000; (Client Address)=us; (Offered Address)=us; (Server Next Address)=255.255.255.255; (Relay Agent Address)=us; (Client Hardware Address)=d85e:d343:3eb::]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=192.168.1.53 | ICMP [RFC792] len=64]
IN 60 [Ethernet len=14; destination=ff:ff:ff:ff:ff:ff; source=e8:4d:74:9f:61:4a | ARP len=28; op=1; (Sender hardware address)=e8:4d:74:9f:61:4a; (Sender protocol address)=192.168.1.1; (Target hardware address)=00:00:00:00:00:00; (Target protocol address)=192.168.1.53]
IN 590 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=192.168.1.1; destination=192.168.1.53 | UDP [RFC768] len=8; (Source port)=67; (Destination port)=68 | DHCPv4 len=273; op=2; Flags=0x0000; (Client Address)=us; (Offered Address)=192.168.1.53; (Server Next Address)=us; (Relay Agent Address)=us; (Client Hardware Address)=d85e:d343:3eb::]
OUT 326 [Ethernet len=14; destination=ff:ff:ff:ff:ff:ff; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=255.255.255.255 | UDP [RFC768] len=8; (Source port)=68; (Destination port)=67 | DHCPv4 len=283; op=1; Flags=0x0000; (Client Address)=us; (Offered Address)=192.168.1.53; (Server Next Address)=us; (Relay Agent Address)=us; (Client Hardware Address)=d85e:d343:3eb::]
IN 590 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=192.168.1.1; destination=192.168.1.53 | UDP [RFC768] len=8; (Source port)=67; (Destination port)=68 | DHCPv4 len=273; op=2; Flags=0x0000; (Client Address)=us; (Offered Address)=192.168.1.53; (Server Next Address)=us; (Relay Agent Address)=us; (Client Hardware Address)=d85e:d343:3eb::]
[119ms] DHCP request completed
2025/12/31 21:59:58 INFO dhcp-complete assignedIP=192.168.1.53 routerIP=192.168.1.1 DNS=[192.168.1.1] subnet=192.168.1.0/24
OUT 42 [Ethernet len=14; destination=ff:ff:ff:ff:ff:ff; source=us | ARP len=28; op=1; (Sender hardware address)=us; (Sender protocol address)=us; (Target hardware address)=00:00:00:00:00:00; (Target protocol address)=192.168.1.1]
IN 60 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | ARP len=28; op=2; (Sender hardware address)=e8:4d:74:9f:61:4a; (Sender protocol address)=192.168.1.1; (Target hardware address)=us; (Target protocol address)=us]
[1.1s] Router ARP resolution
IN 60 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | ARP len=28; op=1; (Sender hardware address)=e8:4d:74:9f:61:4a; (Sender protocol address)=192.168.1.1; (Target hardware address)=00:00:00:00:00:00; (Target protocol address)=us]
OUT 42 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | ARP len=28; op=2; (Sender hardware address)=us; (Sender protocol address)=us; (Target hardware address)=e8:4d:74:9f:61:4a; (Target protocol address)=192.168.1.1]
OUT 83 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=192.168.1.1 | UDP [RFC768] len=8; (Source port)=57216; (Destination port)=53 | DNS len=41]
IN 147 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=us | UDP [RFC768] len=8; (Source port)=53; (Destination port)=57216 | DNS len=105]
[3.5s] NTP IP lookup
OUT 90 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=170.210.222.10 | UDP [RFC768] len=8; (Source port)=1023; (Destination port)=123 | NTP len=48; (Reference Time)=1900-01-01T00:00:00; (Origin Time)=1900-01-01T00:00:00; (Receive Time)=1900-01-01T00:00:00; (Transit Time)=1900-01-01T00:00:00]
IN 90 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=170.210.222.10; destination=us | UDP [RFC768] len=8; (Source port)=123; (Destination port)=1023 | NTP len=48; (Reference Time)=2026-01-01T00:43:04; (Origin Time)=1900-01-01T00:00:00; (Receive Time)=2026-01-01T01:00:03; (Transit Time)=2026-01-01T01:00:03]
[786ms] NTP exchange
NTP completed. You are 11.493283ms ahead of the NTP server
OUT 81 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=192.168.1.1 | UDP [RFC768] len=8; (Source port)=56316; (Destination port)=53 | DNS len=39]
IN 97 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=us | UDP [RFC768] len=8; (Source port)=53; (Destination port)=56316 | DNS len=55]
[1s] resolve google.com
DNS resolution of "google.com" complete and resolved to [142.251.129.142]
[10µs] create HTTP GET request
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=us | ICMP [RFC792] len=64]
OUT 58 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=142.251.129.142 | TCP [RFC9293] len=24; (Source port)=51982; (Destination port)=80; flags=SYN]
IN 98 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=192.168.1.1; destination=us | ICMP [RFC792] len=64]
IN 60 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=142.251.129.142; destination=us | TCP [RFC9293] len=24; (Source port)=80; (Destination port)=51982; flags=SYN,ACK | payload? len=2]
OUT 54 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=142.251.129.142 | TCP [RFC9293] len=20; (Source port)=51982; (Destination port)=80; flags=ACK]
[646ms] TCP dial (handshake)
[5µs] send HTTP request
OUT 161 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=142.251.129.142 | TCP [RFC9293] len=20; (Source port)=51982; (Destination port)=80; flags=PSH,ACK | HTTP len=107]
IN 60 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=142.251.129.142; destination=us | TCP [RFC9293] len=20; (Source port)=80; (Destination port)=51982; flags=ACK | payload? len=6]
IN 846 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=142.251.129.142; destination=us | TCP [RFC9293] len=20; (Source port)=80; (Destination port)=51982; flags=PSH,ACK | HTTP len=792]
IN 60 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=142.251.129.142; destination=us | TCP [RFC9293] len=20; (Source port)=80; (Destination port)=51982; flags=FIN,ACK | payload? len=6]
IN 804 [Ethernet len=14; destination=us; source=e8:4d:74:9f:61:4a | IPv4 len=20; (Type of Service)=0x00; flags=0x0000; source=142.251.129.142; destination=us | TCP [RFC9293] len=20; (Source port)=80; (Destination port)=51982; flags=ACK | HTTP len=750]
OUT 54 [Ethernet len=14; destination=e8:4d:74:9f:61:4a; source=us | IPv4 len=20; (Type of Service)=0x00; flags=0x4000; source=us; destination=142.251.129.142 | TCP [RFC9293] len=20; (Source port)=51982; (Destination port)=80; flags=ACK]
[2.9s] recv http request
HTTP/1.1 301 Moved Permanently
Location: http://www.google.com/
Content-Type: text/html; charset=UTF-8
Content-Security-Policy-Report-Only: object-src 'none';base-uri 'self';script-src 'nonce-v-ysoE0WjLlAMlo2ek5UrA' 'strict-dynamic' 'report-sample' 'unsafe-eval' 'unsafe-inline' https: http:;report-uri https://csp.withgoogle.com/csp/gws/other-hp
Date: Thu, 01 Jan 2026 01:00:08 GMT
Expires: Sat, 31 Jan 2026 01:00:08 GMT
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 219
X-XSS-Protection: 0
X-Frame-Options: SAMEORIGIN
Connection: close
<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>301 Moved</TITLE></HEAD><BODY>
<H1>301 Moved</H1>
The document has moved
<A HREF="http://www.google.com/">here</A>.
</BODY></HTML>
success
```