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use ihl to derive port bytes

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zedddie 2026-03-17 22:27:24 +01:00 • committed by tuturuu
parent da8e70f2e3
commit 50524cb5ae
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GPG key ID: B352C3C2894405A7
2 changed files with 14 additions and 12 deletions
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6
src/sniffing/headers.rs
View file

@ -52,13 +52,15 @@ pub fn sniff_raw_packets(packet: &Packet) -> SniffedPacket {
let ver = packet[0] >> 4;
match ver {
4 => {
let dst_port = Port::from_be_bytes([packet[22], packet[23]]);
// Internet Header Length (IHL).
let ihl = (packet[0] & 0x0F) as usize * 4;
let dst_port = Port::from_be_bytes([packet[ihl+2], packet[ihl+3]]);
let dns;
if dst_port == 53 { dns = true; } else { dns = false; };
// FIXME: hardcoded IPv4 port offset
let v4 = PacketInfo::V4{
src_ip: <Ipv4>::try_from(&packet[12..16])?,
src_port: Port::from_be_bytes([packet[20], packet[21]]),
src_port: Port::from_be_bytes([packet[ihl], packet[ihl+1]]),
dst_ip: <Ipv4>::try_from(&packet[16..20])?,
dst_port,
protocol: match packet[9] {

20
tests/headers.rs
View file

@ -115,7 +115,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [0] IPv4 TCP 192.168.1.100:4832 → 93.184.216.34:443
assert_eq!(
sniff_raw_packets(test_suite[0])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [192, 168, 1, 100],
src_port: 4832,
dst_ip: [93, 184, 216, 34],
@ -127,7 +127,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [1] IPv4 UDP 10.0.0.9:5353 → 224.0.0.251:5353 (mDNS)
assert_eq!(
sniff_raw_packets(test_suite[1])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [10, 0, 0, 9],
src_port: 5353,
dst_ip: [224, 0, 0, 251],
@ -139,7 +139,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [2] IPv4 UDP 10.0.0.9:1024 → 8.8.8.8:53 (DNS)
assert_eq!(
sniff_raw_packets(test_suite[2])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [10, 0, 0, 9],
src_port: 1024,
dst_ip: [8, 8, 8, 8],
@ -151,7 +151,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [3] IPv4 TCP 10.0.0.5:54321 → 10.0.0.1:80 (HTTP)
assert_eq!(
sniff_raw_packets(test_suite[3])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [10, 0, 0, 5],
src_port: 54321,
dst_ip: [10, 0, 0, 1],
@ -163,7 +163,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [4] IPv4 TCP 172.16.0.1:65535 → 172.16.0.2:8080
assert_eq!(
sniff_raw_packets(test_suite[4])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [172, 16, 0, 1],
src_port: 65535,
dst_ip: [172, 16, 0, 2],
@ -175,7 +175,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [5] IPv4 TCP IHL=6 10.0.0.1:9090 → 10.0.0.2:22 (requires IHL-based offset)
assert_eq!(
sniff_raw_packets(test_suite[5])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [10, 0, 0, 1],
src_port: 9090,
dst_ip: [10, 0, 0, 2],
@ -187,7 +187,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [6] IPv4 ICMP (unsupported, "ports" are just ICMP body bytes)
assert_eq!(
sniff_raw_packets(test_suite[6])?,
PacketInfo::V4 {
PacketInfo::V6 { dns: false,
src_ip: [10, 0, 0, 9],
src_port: 2048,
dst_ip: [10, 0, 0, 1],
@ -199,7 +199,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [7] IPv6 TCP [::1]:4000 → [2606:4700::1]:443
assert_eq!(
sniff_raw_packets(test_suite[7])?,
PacketInfo::V6 {
PacketInfo::V6 { dns: false,
src_ip: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
src_port: 4000,
dst_ip: [0x26, 0x06, 0x47, 0x00, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
@ -211,7 +211,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [8] IPv6 UDP [fd00::9]:1234 → [fd00::1]:53 (requires fixing 17 => UDP)
assert_eq!(
sniff_raw_packets(test_suite[8])?,
PacketInfo::V6 {
PacketInfo::V6 { dns: false,
src_ip: [0xFD, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9],
src_port: 1234,
dst_ip: [0xFD, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
@ -223,7 +223,7 @@ fn generic_typeck() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
// [9] IPv6 ICMPv6 (unsupported, "ports" are ICMPv6 body bytes)
assert_eq!(
sniff_raw_packets(test_suite[9])?,
PacketInfo::V6 {
PacketInfo::V6 { dns: false,
src_ip: [0xFE, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],
src_port: 32768,
dst_ip: [0xFF, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1],