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ParseEthernetFrame - Fix vlan calculation (#2295)

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Ted Kruijff 2026-03-26 17:33:12 +01:00 • committed by GitHub
parent b0fa1f8d1b
commit 6aa98b4a66
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GPG key ID: B5690EEEBB952194
2 changed files with 5 additions and 8 deletions
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9
src/core/operations/ParseEthernetFrame.mjs
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@ -74,17 +74,14 @@ class ParseEthernetFrame extends Operation {
const ethType = Utils.byteArrayToChars(input.slice(offset, offset+2));
offset += 2;
if (ethType === "\x08\x00") {
break;
} else if (ethType === "\x81\x00" || ethType === "\x88\xA8") {
if (ethType === "\x81\x00" || ethType === "\x88\xA8") {
// Parse the VLAN tag:
// [0000] 0000 0000 0000
// ^^^ PRIO - Ignored
// ^ DEI - Ignored
// ^^^^ ^^^^ ^^^^ VLAN ID
const vlanTag = input.slice(offset+2, offset+4);
vlans.push((vlanTag[0] & 0b00001111) << 4 | vlanTag[1]);
const vlanTag = input.slice(offset, offset+2);
vlans.push(((vlanTag[0] & 0b00001111) << 8) | vlanTag[1]);
offset += 2;
} else {

4
tests/operations/tests/ParseEthernetFrame.mjs
View file

@ -23,7 +23,7 @@ TestRegister.addTests([
{
name: "Parse Ethernet frame with one VLAN tag (802.1q)",
input: "01000ccdcdd00013c3dfae188100a0760165aaaa",
expectedOutput: "Source MAC: 00:13:c3:df:ae:18\nDestination MAC: 01:00:0c:cd:cd:d0\nVLAN: 117\nData:\naa aa",
expectedOutput: "Source MAC: 00:13:c3:df:ae:18\nDestination MAC: 01:00:0c:cd:cd:d0\nVLAN: 118\nData:\naa aa",
recipeConfig: [
{
"op": "Parse Ethernet frame",
@ -34,7 +34,7 @@ TestRegister.addTests([
{
name: "Parse Ethernet frame with two VLAN tags (802.1ad)",
input: "0019aa7de688002155c8f13c810000d18100001408004500",
expectedOutput: "Source MAC: 00:21:55:c8:f1:3c\nDestination MAC: 00:19:aa:7d:e6:88\nVLAN: 16, 128\nData:\n45 00",
expectedOutput: "Source MAC: 00:21:55:c8:f1:3c\nDestination MAC: 00:19:aa:7d:e6:88\nVLAN: 209, 20\nData:\n45 00",
recipeConfig: [
{
"op": "Parse Ethernet frame",