From ad6b75df3d1238f7e53b355644e2123933a3d2d2 Mon Sep 17 00:00:00 2001
From: lishutong <lishutong@google.com>
Date: Tue, 27 Jul 2021 16:20:47 +0000
Subject: [PATCH] Add prebuild and postbuild info to OTA_analysis.

The metadata file in ota package contains prebuild and postbuild info,
now the basic info section will display those.

Test: mannual tested.
Change-Id: I264fe656ff6fab42d5161100c04210ab9a94c7a0
---
 .../ota_analysis/src/components/BasicInfo.vue | 35 ++++++++++-
 tools/ota_analysis/src/services/payload.js    | 58 +++++++++++++++++--
 2 files changed, 88 insertions(+), 5 deletions(-)

diff --git a/tools/ota_analysis/src/components/BasicInfo.vue b/tools/ota_analysis/src/components/BasicInfo.vue
index 8a3a2ecb2..6c1e36816 100644
--- a/tools/ota_analysis/src/components/BasicInfo.vue
+++ b/tools/ota_analysis/src/components/BasicInfo.vue
@@ -13,6 +13,22 @@
       </li>
     </ul>
   </div>
+  <div
+    v-if="payload && payload.metadata"
+    v-bind="$attrs"
+  >
+    <ul class="align">
+      <li
+        v-for="formatter in MetadataFormat"
+        :key="formatter.name"
+      >
+        <strong> {{ formatter.name }} </strong>
+        <p class="wrap">
+          {{ String(payload[formatter.key]) }}
+        </p>
+      </li>
+    </ul>
+  </div>
   <div v-if="payload && payload.manifest">
     <ul class="align">
       <li>
@@ -47,7 +63,7 @@
 </template>
 
 <script>
-import { Payload } from '@/services/payload.js'
+import { Payload, MetadataFormat } from '@/services/payload.js'
 
 export default {
   props: {
@@ -60,6 +76,11 @@ export default {
       required: true,
     },
   },
+  data() {
+    return {
+      MetadataFormat
+    }
+  }
 }
 </script>
 
@@ -75,4 +96,16 @@ export default {
 .align strong::after {
   content: ':';
 }
+
+li {
+  list-style-type: none;
+}
+
+.wrap {
+  width: 50%;
+  display: inline-block;
+  white-space: pre-wrap;
+  word-wrap: break-word;
+  font-family: inherit;
+}
 </style>
\ No newline at end of file
diff --git a/tools/ota_analysis/src/services/payload.js b/tools/ota_analysis/src/services/payload.js
index 5fdb95f88..489f2bca1 100644
--- a/tools/ota_analysis/src/services/payload.js
+++ b/tools/ota_analysis/src/services/payload.js
@@ -10,11 +10,33 @@
 import * as zip from '@zip.js/zip.js/dist/zip-full.min.js'
 import { chromeos_update_engine as update_metadata_pb } from './update_metadata_pb.js'
 
-const /** Number */ _MAGIC = 'CrAU'
+const /** String */ _MAGIC = 'CrAU'
 const /** Number */ _VERSION_SIZE = 8
 const /** Number */ _MANIFEST_LEN_SIZE = 8
 const /** Number */ _METADATA_SIGNATURE_LEN_SIZE = 4
 const /** Number */ _BRILLO_MAJOR_PAYLOAD_VERSION = 2
+export const /** Array<Object> */ MetadataFormat = [
+  {
+    prefix: 'pre-build',
+    key: 'preBuild',
+    name: 'Pre-build'
+  },
+  {
+    prefix: 'pre-build-incremental',
+    key: 'preBuildVersion',
+    name: 'Pre-build version'
+  },
+  {
+    prefix: 'post-build',
+    key: 'postBuild',
+    name: 'Post-build'
+  },
+  {
+    prefix: 'post-build-incremental',
+    key: 'postBuildVersion',
+    name: 'Post-build version'
+  }
+]
 
 export class Payload {
   /**
@@ -26,7 +48,10 @@ export class Payload {
     this.cursor = 0
   }
 
-  async unzipPayload() {
+  /**
+   * Unzip the OTA package, get payload.bin and metadata
+   */
+  async unzip() {
     let /** Array<Entry> */ entries = await this.packedFile.getEntries()
     this.payload = null
     for (let entry of entries) {
@@ -34,6 +59,9 @@ export class Payload {
         //TODO: only read in the manifest instead of the whole payload
         this.payload = await entry.getData(new zip.BlobWriter())
       }
+      if (entry.filename == 'META-INF/com/android/metadata') {
+        this.metadata = await entry.getData(new zip.TextWriter())
+      }
     }
     if (!this.payload) {
       alert('Please select a legit OTA package')
@@ -106,11 +134,22 @@ export class Payload {
       .decode(signature_raw)
   }
 
+  parseMetadata() {
+    for (let formatter of MetadataFormat) {
+      let regex = new RegExp(formatter.prefix + '.+')
+      if (this.metadata.match(regex)) {
+        this[formatter.key] =
+          trimEntry(this.metadata.match(regex)[0], formatter.prefix)
+      } else this[formatter.key] = ''
+    }
+  }
+
   async init() {
-    await this.unzipPayload()
+    await this.unzip()
     this.readHeader()
     this.readManifest()
     this.readSignature()
+    this.parseMetadata()
   }
 
 }
@@ -149,7 +188,7 @@ export class MergeOpType {
 export function octToHex(bufferArray, space = true, maxLine = 16) {
   let hex_table = ''
   for (let i = 0; i < bufferArray.length; i++) {
-    if (bufferArray[i].toString(16).length===2) {
+    if (bufferArray[i].toString(16).length === 2) {
       hex_table += bufferArray[i].toString(16) + (space ? ' ' : '')
     } else {
       hex_table += '0' + bufferArray[i].toString(16) + (space ? ' ' : '')
@@ -159,4 +198,15 @@ export function octToHex(bufferArray, space = true, maxLine = 16) {
     }
   }
   return hex_table
+}
+
+/**
+ * Trim the prefix in an entry. This is required because the lookbehind
+ * regular expression is not supported in safari yet.
+ * @param {String} entry
+ * @param {String} prefix
+ * @return String
+ */
+function trimEntry(entry, prefix) {
+  return entry.slice(prefix.length + 1, entry.length)
 }
\ No newline at end of file