Addressing API comments.

Bug: 266719856
Fixes: 266719856
Test: atest SettingsTest
Change-Id: Idbf60f3a653feede3d85895120deaeb5544acc16
diff --git a/core/java/com/android/internal/security/VerityUtils.java b/core/java/com/android/internal/security/VerityUtils.java
index 786941f..74a9d16 100644
--- a/core/java/com/android/internal/security/VerityUtils.java
+++ b/core/java/com/android/internal/security/VerityUtils.java
@@ -81,6 +81,15 @@
         }
     }
 
+    /** Enables fs-verity for an open file without signature. */
+    public static void setUpFsverity(int fd) throws IOException {
+        int errno = enableFsverityForFdNative(fd);
+        if (errno != 0) {
+            throw new IOException("Failed to enable fs-verity on FD(" + fd + "): "
+                    + Os.strerror(errno));
+        }
+    }
+
     /** Returns whether the file has fs-verity enabled. */
     public static boolean hasFsverity(@NonNull String filePath) {
         int retval = statxForFsverityNative(filePath);
@@ -211,6 +220,7 @@
     }
 
     private static native int enableFsverityNative(@NonNull String filePath);
+    private static native int enableFsverityForFdNative(int fd);
     private static native int measureFsverityNative(@NonNull String filePath,
             @NonNull byte[] digest);
     private static native int statxForFsverityNative(@NonNull String filePath);
diff --git a/core/jni/com_android_internal_security_VerityUtils.cpp b/core/jni/com_android_internal_security_VerityUtils.cpp
index 3e5689b..4a9e2d4 100644
--- a/core/jni/com_android_internal_security_VerityUtils.cpp
+++ b/core/jni/com_android_internal_security_VerityUtils.cpp
@@ -38,13 +38,8 @@
 
 namespace {
 
-int enableFsverity(JNIEnv *env, jobject /* clazz */, jstring filePath) {
-    ScopedUtfChars path(env, filePath);
-    if (path.c_str() == nullptr) {
-        return EINVAL;
-    }
-    ::android::base::unique_fd rfd(open(path.c_str(), O_RDONLY | O_CLOEXEC));
-    if (rfd.get() < 0) {
+int enableFsverityForFd(JNIEnv *env, jobject clazz, jint fd) {
+    if (fd < 0) {
         return errno;
     }
 
@@ -55,12 +50,21 @@
     arg.salt_size = 0;
     arg.salt_ptr = reinterpret_cast<uintptr_t>(nullptr);
 
-    if (ioctl(rfd.get(), FS_IOC_ENABLE_VERITY, &arg) < 0) {
+    if (ioctl(fd, FS_IOC_ENABLE_VERITY, &arg) < 0) {
         return errno;
     }
     return 0;
 }
 
+int enableFsverity(JNIEnv *env, jobject clazz, jstring filePath) {
+    ScopedUtfChars path(env, filePath);
+    if (path.c_str() == nullptr) {
+        return EINVAL;
+    }
+    ::android::base::unique_fd rfd(open(path.c_str(), O_RDONLY | O_CLOEXEC));
+    return enableFsverityForFd(env, clazz, rfd.get());
+}
+
 // Returns whether the file has fs-verity enabled.
 // 0 if it is not present, 1 if is present, and -errno if there was an error.
 int statxForFsverity(JNIEnv *env, jobject /* clazz */, jstring filePath) {
@@ -126,6 +130,7 @@
 }
 const JNINativeMethod sMethods[] = {
         {"enableFsverityNative", "(Ljava/lang/String;)I", (void *)enableFsverity},
+        {"enableFsverityForFdNative", "(I)I", (void *)enableFsverityForFd},
         {"statxForFsverityNative", "(Ljava/lang/String;)I", (void *)statxForFsverity},
         {"measureFsverityNative", "(Ljava/lang/String;[B)I", (void *)measureFsverity},
 };
diff --git a/services/api/current.txt b/services/api/current.txt
index 70ee3b8..a4deed3 100644
--- a/services/api/current.txt
+++ b/services/api/current.txt
@@ -227,8 +227,9 @@
 
 package com.android.server.security {
 
-  public final class FileIntegrityLocal {
-    method public static void setUpFsVerity(@NonNull String) throws java.io.IOException;
+  public final class FileIntegrity {
+    method public static void setUpFsVerity(@NonNull java.io.File) throws java.io.IOException;
+    method public static void setUpFsVerity(@NonNull android.os.ParcelFileDescriptor) throws java.io.IOException;
   }
 
 }
diff --git a/services/core/java/com/android/server/pm/Settings.java b/services/core/java/com/android/server/pm/Settings.java
index 9c91879..7e7205d 100644
--- a/services/core/java/com/android/server/pm/Settings.java
+++ b/services/core/java/com/android/server/pm/Settings.java
@@ -120,7 +120,7 @@
 import com.android.server.pm.verify.domain.DomainVerificationLegacySettings;
 import com.android.server.pm.verify.domain.DomainVerificationManagerInternal;
 import com.android.server.pm.verify.domain.DomainVerificationPersistence;
-import com.android.server.security.FileIntegrityLocal;
+import com.android.server.security.FileIntegrity;
 import com.android.server.utils.Slogf;
 import com.android.server.utils.Snappable;
 import com.android.server.utils.SnapshotCache;
@@ -2714,8 +2714,8 @@
             }
 
             try {
-                FileIntegrityLocal.setUpFsVerity(mSettingsFilename.getAbsolutePath());
-                FileIntegrityLocal.setUpFsVerity(mSettingsReserveCopyFilename.getAbsolutePath());
+                FileIntegrity.setUpFsVerity(mSettingsFilename);
+                FileIntegrity.setUpFsVerity(mSettingsReserveCopyFilename);
             } catch (IOException e) {
                 Slog.e(TAG, "Failed to verity-protect settings", e);
             }
diff --git a/services/core/java/com/android/server/security/FileIntegrityLocal.java b/services/core/java/com/android/server/security/FileIntegrity.java
similarity index 63%
rename from services/core/java/com/android/server/security/FileIntegrityLocal.java
rename to services/core/java/com/android/server/security/FileIntegrity.java
index 8c7219b..7b87d99 100644
--- a/services/core/java/com/android/server/security/FileIntegrityLocal.java
+++ b/services/core/java/com/android/server/security/FileIntegrity.java
@@ -18,19 +18,22 @@
 
 import android.annotation.NonNull;
 import android.annotation.SystemApi;
+import android.os.ParcelFileDescriptor;
 
 import com.android.internal.security.VerityUtils;
 
+import java.io.File;
 import java.io.IOException;
 
+
 /**
  * In-process API for server side FileIntegrity related infrastructure.
  *
  * @hide
  */
 @SystemApi(client = SystemApi.Client.SYSTEM_SERVER)
-public final class FileIntegrityLocal {
-    private FileIntegrityLocal() {}
+public final class FileIntegrity {
+    private FileIntegrity() {}
 
     /**
      * Enables fs-verity, if supported by the filesystem.
@@ -38,7 +41,18 @@
      * @hide
      */
     @SystemApi(client = SystemApi.Client.SYSTEM_SERVER)
-    public static void setUpFsVerity(@NonNull String filePath) throws IOException {
-        VerityUtils.setUpFsverity(filePath);
+    public static void setUpFsVerity(@NonNull File file) throws IOException {
+        VerityUtils.setUpFsverity(file.getAbsolutePath());
+    }
+
+    /**
+     * Enables fs-verity, if supported by the filesystem.
+     * @see <a href="https://www.kernel.org/doc/html/latest/filesystems/fsverity.html">
+     * @hide
+     */
+    @SystemApi(client = SystemApi.Client.SYSTEM_SERVER)
+    public static void setUpFsVerity(@NonNull ParcelFileDescriptor parcelFileDescriptor)
+            throws IOException {
+        VerityUtils.setUpFsverity(parcelFileDescriptor.getFd());
     }
 }