attempt to wipe digital car keys when clearing userdata from fastbootd

A WipeKeys function is optionally compiled into the recovery UI on
Pixels where digital car keys are supported. This change looks for that
function and, if found, uses it to clear the keys during a userdata
wipe.

Includes are reordered based on repohook requirements.

Bug: 203234558
Test: adb reboot fastboot && fastboot -w; then check for key after reboot
Signed-off-by: Jeffrey Carlyle <jcarlyle@google.com>
Change-Id: I46a58f7d521fdefd0675be0b4180bbefdee2e660
Merged-In: I46a58f7d521fdefd0675be0b4180bbefdee2e660

1 files changed, 41 insertions, 8 deletions

diff --git a/fastboot/Fastboot.cpp b/fastboot/Fastboot.cpp
index 922334b..913d82d 100644
--- a/fastboot/Fastboot.cpp
+++ b/fastboot/Fastboot.cpp
@@ -16,15 +16,16 @@
 
 #include "fastboot/Fastboot.h"
 
-#include <string>
-#include <unordered_map>
-#include <vector>
-#include <map>
-
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
+#include <dlfcn.h>
+
+#include <map>
+#include <string>
+#include <unordered_map>
+#include <vector>
 
 // FS headers
 #include <ext4_utils/wipe.h>
@@ -169,11 +170,35 @@ enum WipeVolumeStatus wipe_volume(const std::string &volume) {
     return WIPE_OK;
 }
 
+// Attempt to reuse a WipeKeys function that might be found in the recovery
+// library in order to clear any digital car keys on the secure element.
+bool WipeDigitalCarKeys(void) {
+    static constexpr const char *kDefaultLibRecoveryUIExt = "librecovery_ui_ext.so";
+    void *librecovery_ui_ext = dlopen(kDefaultLibRecoveryUIExt, RTLD_NOW);
+    if (librecovery_ui_ext == nullptr) {
+        // Dynamic library not found. Returning true since this likely
+        // means target does not support DCK.
+        return true;
+    }
+
+    bool *(*WipeKeysFunc)(void *const);
+    reinterpret_cast<void *&>(WipeKeysFunc) = dlsym(librecovery_ui_ext, "WipeKeys");
+    if (WipeKeysFunc == nullptr) {
+        // No WipeKeys implementation found. Returning true since this likely
+        // means target does not support DCK.
+        return true;
+    }
+
+    return (*WipeKeysFunc)(nullptr);
+}
+
 Return<void> Fastboot::doOemSpecificErase(V1_1::IFastboot::doOemSpecificErase_cb _hidl_cb) {
     // Erase metadata partition along with userdata partition.
     // Keep erasing Titan M even if failing on this case.
     auto wipe_status = wipe_volume("/metadata");
 
+    bool dck_wipe_success = WipeDigitalCarKeys();
+
     // Connect to Titan M
     ::nos::NuggetClient client;
     client.Open();
@@ -188,19 +213,27 @@ Return<void> Fastboot::doOemSpecificErase(V1_1::IFastboot::doOemSpecificErase_cb
     memcpy(magic.data(), &magicValue, sizeof(magicValue));
     const uint8_t retry_count = 5;
     uint32_t nugget_status;
-    for(uint8_t i = 0; i < retry_count; i++) {
+    for (uint8_t i = 0; i < retry_count; i++) {
         nugget_status = client.CallApp(APP_ID_NUGGET, NUGGET_PARAM_NUKE_FROM_ORBIT, magic, nullptr);
-        if (nugget_status == APP_SUCCESS && wipe_status == WIPE_OK) {
+        if (nugget_status == APP_SUCCESS && wipe_status == WIPE_OK && dck_wipe_success) {
             _hidl_cb({Status::SUCCESS, wipe_vol_ret_msg[wipe_status]});
             return Void();
         }
     }
 
     // Return exactly what happened
-    if (nugget_status != APP_SUCCESS && wipe_status != WIPE_OK) {
+    if (nugget_status != APP_SUCCESS && wipe_status != WIPE_OK && !dck_wipe_success) {
+        _hidl_cb({Status::FAILURE_UNKNOWN, "Fail on wiping metadata, Titan M user data, and DCK"});
+    } else if (nugget_status != APP_SUCCESS && wipe_status != WIPE_OK) {
         _hidl_cb({Status::FAILURE_UNKNOWN, "Fail on wiping metadata and Titan M user data"});
+    } else if (nugget_status != APP_SUCCESS && !dck_wipe_success) {
+        _hidl_cb({Status::FAILURE_UNKNOWN, "Titan M user data and DCK wipe failed"});
     } else if (nugget_status != APP_SUCCESS) {
         _hidl_cb({Status::FAILURE_UNKNOWN, "Titan M user data wipe failed"});
+    } else if (wipe_status != WIPE_OK && !dck_wipe_success) {
+        _hidl_cb({Status::FAILURE_UNKNOWN, "Fail on wiping metadata and DCK"});
+    } else if (!dck_wipe_success) {
+        _hidl_cb({Status::FAILURE_UNKNOWN, "DCK wipe failed"});
     } else {
         if (wipe_vol_ret_msg.find(wipe_status) != wipe_vol_ret_msg.end())
             _hidl_cb({Status::FAILURE_UNKNOWN, wipe_vol_ret_msg[wipe_status]});