From 69cb96e53877f835d5273a2e6d26bc72f4d2c443 Mon Sep 17 00:00:00 2001
From: Robin Getz <rgetz503@gmail.com>
Date: Mon, 17 Nov 2025 16:50:06 -0500
Subject: [PATCH] network: correct MAC classification to match RFC 9542 (SLAP)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

RFC 9542 replaces RFC 7042 and defines the Structured Local Address Plan (SLAP),
subdividing the locally administered address space into four distinct quadrants:
 - Administratively Assigned (x2),
 - Reserved (x6),
 - Extended Local (xA),
 - and Standard Assigned (xE).

Modern systems — including iOS, Android, virtualization platforms, containers,
and privacy-preserving network stacks — use these ranges extensively.

This patch updates the classification logic to implement RFC 9542 semantics:
 - Decode SLAP quadrants for local addresses (x2/x6/xA/xE)
 - Distinguish global vendor MACs from global addresses with unknown vendors
 - Correctly identify multicast addresses (bit 0 set) and avoid mislabeling them as local
 - Preserve support for mock ip- addresses and malformed/unknown formats

This improves accuracy for randomized mobile MACs, manufacturer local address
blocks, protocol-assigned local addresses, and security-focused deployments
where correct interpretation of the first-octet bit fields matters.

Signed-off-by: Robin Getz <rgetz503@gmail.com>
---
 scripts/js/network.js | 59 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 50 insertions(+), 9 deletions(-)

diff --git a/scripts/js/network.js b/scripts/js/network.js
index e6116e8f10..350ddab5bb 100644
--- a/scripts/js/network.js
+++ b/scripts/js/network.js
@@ -179,16 +179,57 @@ $(() => {
       $("td:eq(0)", row).html(ips.join("<br>"));
 
       // MAC + Vendor field if available
-      if (data.macVendor && data.macVendor.length > 0) {
-        $("td:eq(1)", row).html(
-          utils.escapeHtml(data.hwaddr) + "<br>" + utils.escapeHtml(data.macVendor)
-        );
-      }
-
-      // Make mock MAC addresses italics and add title
+      const cell = $("td:eq(1)", row);
       if (data.hwaddr.startsWith("ip-")) {
-        $("td:eq(1)", row).css("font-style", "italic");
-        $("td:eq(1)", row).attr("title", "Mock MAC address");
+        // Case 1 - Make mock MAC addresses italics and add title
+        cell.css("font-style", "italic").attr("title", "Mock MAC address");
+      } else if (data.hwaddr.includes(":")) {
+        // Case 2 — MAC-like address
+        const parts = data.hwaddr.split(":");
+        const firstOctet = Number.parseInt(parts[0], 16);
+        // Arithmetic-only flag detection
+        const isMulticast = firstOctet % 2 === 1; // bit 0
+        const isLocal = Math.floor(firstOctet / 2) % 2 === 1; // bit 1
+        // Multicast overrides all SLAP meaning
+        if (isMulticast) {
+          // Case 2.1 - Multicast
+          cell.html(utils.escapeHtml(data.hwaddr) + "<br>Multicast Address");
+        } else if (isLocal) {
+          // Case 2.2 - Local SLAP
+          let slapLabel = null;
+          // SLAP quadrant resolution (RFC 9542)
+          const ts = Math.floor(firstOctet / 4) % 4; // bits 2–3 become bits 0–1
+          switch (ts) {
+            case 0x0:
+              slapLabel = "Administratively Assigned (AAI)";
+              break;
+            case 0x1:
+              slapLabel = "Extended Local (ELI)";
+              break;
+            case 0x2:
+              slapLabel = "Reserved";
+              break;
+            case 0x3:
+              slapLabel = "Standard Assigned (SAI)";
+              break;
+            default:
+              // satisfy ESLint
+              slapLabel = "Unclassified";
+              break;
+          }
+
+          cell.html(utils.escapeHtml(data.hwaddr) + "<br>Locally Administered");
+          cell.css("font-style", "italic").attr("title", slapLabel);
+        } else if (data.macVendor && data.macVendor.length > 0) {
+          // Case 2.3 - Global address space (U/L = 0)
+          cell.html(utils.escapeHtml(data.hwaddr) + "<br>" + utils.escapeHtml(data.macVendor));
+        } else {
+          // Case 2.4 - Lookup failed
+          cell.html(utils.escapeHtml(data.hwaddr) + "<br>Global: Unknown");
+        }
+      } else {
+        // Case 3 — Not IP-mock, not MAC-like
+        cell.css("color", "red").html(utils.escapeHtml(data.hwaddr) + "<br>Unknown Format");
       }
 
       // Add delete button