From 00001111031ca5206f06d5d0e4ad877f3ff595da Mon Sep 17 00:00:00 2001
From: Billy Lau <billylau@google.com>
Date: Tue, 10 Jan 2023 14:13:20 -0600
Subject: [PATCH] BinaryTransparencyService: Fix printPackageInstallationInfo

It seems that APEX_PRELOAD_LOCATION_ERROR is consistently returned
as the value of original APEX location when calling
`getOriginalApexPreinstalledLocation` when preloaded APEXs are
compressed.

While this change does not address the root issue of why that is
the case, it prevents the error value to be used as a legitimate
path to compute digests for by guarding the control flow based on
sane values of apex install location.

Bug: 264925790
Test: Manual.
	adb shell cmd transparency get apex_info -v
Change-Id: I924ba889cb6d11a874cf06ca8692f8320b86b588
---
 .../server/BinaryTransparencyService.java     | 43 ++++++++++---------
 1 file changed, 23 insertions(+), 20 deletions(-)

diff --git a/services/core/java/com/android/server/BinaryTransparencyService.java b/services/core/java/com/android/server/BinaryTransparencyService.java
index 819c948fd0e31..68722d207ae3c 100644
--- a/services/core/java/com/android/server/BinaryTransparencyService.java
+++ b/services/core/java/com/android/server/BinaryTransparencyService.java
@@ -531,27 +531,30 @@ public class BinaryTransparencyService extends SystemService {
                         pw.println("|--> Pre-installed package install location: "
                                 + origPackageFilepath);
 
-                        if (useSha256) {
-                            String sha256Digest = PackageUtils.computeSha256DigestForLargeFile(
-                                    origPackageFilepath, PackageUtils.createLargeFileBuffer());
-                            pw.println("|--> Pre-installed package SHA-256 digest: "
-                                    + sha256Digest);
-                        }
+                        if (!origPackageFilepath.equals(APEX_PRELOAD_LOCATION_ERROR)) {
+                            if (useSha256) {
+                                String sha256Digest = PackageUtils.computeSha256DigestForLargeFile(
+                                        origPackageFilepath, PackageUtils.createLargeFileBuffer());
+                                pw.println("|--> Pre-installed package SHA-256 digest: "
+                                        + sha256Digest);
+                            }
 
-
-                        Map<Integer, byte[]> contentDigests = computeApkContentDigest(
-                                origPackageFilepath);
-                        if (contentDigests == null) {
-                            pw.println("ERROR: Failed to compute package content digest for "
-                                    + origPackageFilepath);
-                        } else {
-                            for (Map.Entry<Integer, byte[]> entry : contentDigests.entrySet()) {
-                                Integer algorithmId = entry.getKey();
-                                byte[] contentDigest = entry.getValue();
-                                pw.println("|--> Pre-installed package content digest: "
-                                        + HexEncoding.encodeToString(contentDigest, false));
-                                pw.println("|--> Pre-installed package content digest algorithm: "
-                                        + translateContentDigestAlgorithmIdToString(algorithmId));
+                            Map<Integer, byte[]> contentDigests = computeApkContentDigest(
+                                    origPackageFilepath);
+                            if (contentDigests == null) {
+                                pw.println("|--> ERROR: Failed to compute package content digest "
+                                        + "for " + origPackageFilepath);
+                            } else {
+                                for (Map.Entry<Integer, byte[]> entry : contentDigests.entrySet()) {
+                                    Integer algorithmId = entry.getKey();
+                                    byte[] contentDigest = entry.getValue();
+                                    pw.println("|--> Pre-installed package content digest: "
+                                            + HexEncoding.encodeToString(contentDigest, false));
+                                    pw.println("|--> Pre-installed package content digest "
+                                            + "algorithm: "
+                                            + translateContentDigestAlgorithmIdToString(
+                                                    algorithmId));
+                                }
                             }
                         }
                     }