Bug 1881524 - Update ipv6 representation algorithm r=keeler,manuel

vladski-i · mb · commit 869f4cfd7ab7 · 2025-09-23T08:44:53.000Z
Differential Revision: https://phabricator.services.mozilla.com/D265461
diff --git a/toolkit/components/certviewer/content/certDecoder.mjs b/toolkit/components/certviewer/content/certDecoder.mjs
@@ -8,6 +8,7 @@ import {
   ECPublicKey,
   RSAPublicKey,
 } from "./vendor/pkijs.js";
+import { hexToIpv6Repr, b64ToPEM } from "./components/utils.mjs";
 
 const getTimeZone = () => {
   let timeZone = new Date().toString().match(/\(([A-Za-z\s].*)\)/);
@@ -156,14 +157,7 @@ const getSubjectAltNames = (x509, criticalExtensions) => {
             ];
           } else if (address.length === 32) {
             // ipv6
-            return [
-              strings.san[type],
-              address
-                .toLowerCase()
-                .match(/.{1,4}/g)
-                .join(":")
-                .replace(/\b:?(?:0+:?){2,}/, "::"),
-            ];
+            return [strings.san[type], hexToIpv6Repr(address)];
           }
           return [strings.san[type], "Unknown IP address"];
 
@@ -442,11 +436,6 @@ const getMicrosoftCryptographicExtensions = (x509, criticalExtensions) => {
   return msCrypto;
 };
 
-const b64ToPEM = string => {
-  let wrapped = string.match(/.{1,64}/g).join("\r\n");
-  return `-----BEGIN CERTIFICATE-----\r\n${wrapped}\r\n-----END CERTIFICATE-----\r\n`;
-};
-
 export const parse = async certificate => {
   // certificate could be an array of BER or an array of buffers
   const supportedExtensions = [
diff --git a/toolkit/components/certviewer/content/components/utils.mjs b/toolkit/components/certviewer/content/components/utils.mjs
@@ -24,3 +24,48 @@ export const b64ToPEM = string => {
   let wrapped = string.match(/.{1,64}/g).join("\r\n");
   return `-----BEGIN CERTIFICATE-----\r\n${wrapped}\r\n-----END CERTIFICATE-----\r\n`;
 };
+
+export const hexToIpv6Repr = ipAddressHex => {
+  let chunks = ipAddressHex
+    .match(/.{4}/g)
+    .map(x => parseInt(x, 16).toString(16));
+  let longestZeroRunStartIndex = 0;
+  let longestZeroRunFound = false;
+  let longestZeroRunLength = 1;
+  let isCounting = false;
+  let currentZeroRunLength = 0;
+  let currentZeroRunStartIndex = 0;
+  for (let i = 0; i < chunks.length; i++) {
+    if (chunks[i] == "0" && !isCounting) {
+      isCounting = true;
+      currentZeroRunStartIndex = i;
+      currentZeroRunLength = 1;
+    } else if (chunks[i] == "0" && isCounting) {
+      currentZeroRunLength++;
+    } else if (chunks[i] != "0" && isCounting) {
+      if (currentZeroRunLength > longestZeroRunLength) {
+        longestZeroRunLength = currentZeroRunLength;
+        longestZeroRunFound = true;
+        longestZeroRunStartIndex = currentZeroRunStartIndex;
+        currentZeroRunLength = 0;
+        isCounting = false;
+      }
+    }
+  }
+  if (isCounting && currentZeroRunLength > longestZeroRunLength) {
+    longestZeroRunLength = currentZeroRunLength;
+    longestZeroRunFound = true;
+    longestZeroRunStartIndex = currentZeroRunStartIndex;
+  }
+  if (longestZeroRunFound) {
+    if (longestZeroRunStartIndex + longestZeroRunLength == chunks.length) {
+      chunks.push("");
+    }
+    if (longestZeroRunStartIndex != 0) {
+      chunks.splice(longestZeroRunStartIndex, longestZeroRunLength, "");
+    } else {
+      chunks.splice(0, longestZeroRunLength, ":");
+    }
+  }
+  return chunks.join(":");
+};
diff --git a/toolkit/components/certviewer/tests/chrome/chrome.toml b/toolkit/components/certviewer/tests/chrome/chrome.toml
@@ -9,5 +9,7 @@ support-files = ["parseOutput.mjs"]
 ["test_certDecoderFields.html"]
 support-files = ["CSoutput.mjs"]
 
+["test_hexToIpv6Repr.html"]
+
 ["test_kebabCaseInAdjustCertInformation.html"]
 support-files = ["parseOutput.mjs"]
diff --git a/toolkit/components/certviewer/tests/chrome/test_hexToIpv6Repr.html b/toolkit/components/certviewer/tests/chrome/test_hexToIpv6Repr.html
@@ -0,0 +1,69 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>certviewer ipv6 representation test</title>
+    <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
+    <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+    <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+  </head>
+<body>
+  <script type="module">
+
+    async function doTest() {
+      const { hexToIpv6Repr } = await import("chrome://global/content/certviewer/components/utils.mjs");
+
+      ok(hexToIpv6Repr, "hexToIpv6Repr should be available in this context");
+
+      let tests = [
+        {
+          input: "00000000111100000000000000001111",
+          expected: "0:0:1111::1111"
+        },
+        {
+          input: "262000fe0000000000000000000000fe",
+          expected: "2620:fe::fe"
+        },
+        {
+          input: "2602ff3a0001abad0c0f0feeabadcafe",
+          expected: "2602:ff3a:1:abad:c0f:fee:abad:cafe"
+        },
+        {
+          input: "00000000000000000000000000000000",
+          expected: "::"
+        },
+        {
+          input: "00000000000000000000000000000001",
+          expected: "::1"
+        },
+        {
+          input: "10000000000000000000000000000000",
+          expected: "1000::"
+        },
+        {
+          input: "2602ff3a1001abad1c0f1feeabadcafe",
+          expected: "2602:ff3a:1001:abad:1c0f:1fee:abad:cafe"
+        },
+        {
+          input: "260200001001abad1c0f1feeabadcafe",
+          expected: "2602:0:1001:abad:1c0f:1fee:abad:cafe"
+        },
+        {
+          input: "00000000000011110000000000001111",
+          expected: "::1111:0:0:0:1111"
+        }
+      ];
+
+      for (let test of tests) {
+        let result = hexToIpv6Repr(test.input);
+        is(result, test.expected, `Ipv6 address incorrectly parsed`);
+      }
+
+      SimpleTest.finish();
+    }
+
+    SimpleTest.waitForExplicitFinish();
+    doTest();
+
+  </script>
+</body>
+</html>
