recovery: Handle oemunlock command

 * Conditionally compile support based on TARGET_HAVE_OEMLOCK.
 * Use liboemunlock for device specific support.

Change-Id: I1cf1fef8e30075b0586bb86625b7df49723974cb

4 files changed, 66 insertions, 7 deletions

diff --git a/Android.mk b/Android.mk
index c5fdbd1..55adbaa 100644
--- a/Android.mk
+++ b/Android.mk
@@ -102,6 +102,13 @@ LOCAL_STATIC_LIBRARIES := \
     libext2_blkid \
     libext2_uuid
 
+# OEMLOCK support requires a device specific liboemlock be supplied.
+# See comments in recovery.cpp for the API.
+ifeq ($(TARGET_HAVE_OEMLOCK), true)
+    LOCAL_CFLAGS += -DHAVE_OEMLOCK
+    LOCAL_STATIC_LIBRARIES += liboemlock
+endif
+
 LOCAL_MODULE_PATH := $(TARGET_RECOVERY_ROOT_OUT)/sbin
 
 ifeq ($(TARGET_USE_MDTP), true)
diff --git a/recovery.cpp b/recovery.cpp
index d3dc398..3a1fd61 100644
--- a/recovery.cpp
+++ b/recovery.cpp
@@ -61,6 +61,39 @@ extern "C" {
 
 struct selabel_handle *sehandle;
 
+#ifdef HAVE_OEMLOCK
+
+/*
+ * liboemlock must supply the following C symbols:
+ *
+ *   - int oemlock_get()
+ *
+ *     Returns the current state of the OEM lock, if available.
+ *       -1: Not available and/or error
+ *        0: Unlocked
+ *        1: Locked
+ *
+ *  - int oemlock_set(int lock)
+ *
+ *      Sets the state of the OEM lock.  The "lock" parameter will be set
+ *      to 0 for unlock and 1 for lock.
+ *
+ *      Returns 0 on success, -1 on error
+ */
+extern "C" {
+int oemlock_get();
+int oemlock_set(int lock);
+}
+
+enum OemLockOp {
+    OEM_LOCK_NONE,
+    OEM_LOCK_UNLOCK
+};
+
+static OemLockOp oem_lock = OEM_LOCK_NONE;
+
+#endif
+
 static const struct option OPTIONS[] = {
   { "send_intent", required_argument, NULL, 'i' },
   { "update_package", required_argument, NULL, 'u' },
@@ -302,6 +335,14 @@ get_args(int *argc, char ***argv) {
             (*argv)[0] = strdup(arg);
             for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
                 if ((arg = strtok(NULL, "\n")) == NULL) break;
+                // Arguments that may only be passed in BCB
+#ifdef HAVE_OEMLOCK
+                if (strcmp(arg, "--oemunlock") == 0) {
+                    oem_lock = OEM_LOCK_UNLOCK;
+                    --*argc;
+                    continue;
+                }
+#endif
                 (*argv)[*argc] = strdup(arg);
             }
             LOGI("Got arguments from boot message\n");
@@ -510,7 +551,7 @@ typedef struct _saved_log_file {
     struct _saved_log_file* next;
 } saved_log_file;
 
-static bool erase_volume(const char* volume) {
+static bool erase_volume(const char* volume, bool force = false) {
     bool is_cache = (strcmp(volume, CACHE_ROOT) == 0);
 
     ui->SetBackground(RecoveryUI::ERASING);
@@ -518,7 +559,7 @@ static bool erase_volume(const char* volume) {
 
     saved_log_file* head = NULL;
 
-    if (is_cache) {
+    if (!force && is_cache) {
         // If we're reformatting /cache, we load any past logs
         // (i.e. "/cache/recovery/last_*") and the current log
         // ("/cache/recovery/log") into memory, so we can restore them after
@@ -568,9 +609,9 @@ static bool erase_volume(const char* volume) {
     if (volume[0] == '/') {
         ensure_path_unmounted(volume);
     }
-    int result = format_volume(volume);
+    int result = format_volume(volume, force);
 
-    if (is_cache) {
+    if (!force && is_cache) {
         while (head) {
             FILE* f = fopen_path(head->name, "wb");
             if (f) {
@@ -1343,6 +1384,17 @@ main(int argc, char **argv) {
 
     int status = INSTALL_SUCCESS;
 
+#ifdef HAVE_OEMLOCK
+    if (oem_lock == OEM_LOCK_UNLOCK) {
+        if (device->WipeData()) status = INSTALL_ERROR;
+        if (erase_volume("/data", true)) status = INSTALL_ERROR;
+        if (wipe_cache && erase_volume("/cache", true)) status = INSTALL_ERROR;
+        if (status != INSTALL_SUCCESS) ui->Print("Data wipe failed.\n");
+        if (oemlock_set(0)) status = INSTALL_ERROR;
+        // Force reboot regardless of actual status
+        status = INSTALL_SUCCESS;
+    } else
+#endif
     if (update_package != NULL) {
         status = install_package(update_package, &should_wipe_cache, TEMPORARY_INSTALL_FILE, true);
         if (status == INSTALL_SUCCESS && should_wipe_cache) {
diff --git a/roots.cpp b/roots.cpp
index fda8f61..d27a2dd 100644
--- a/roots.cpp
+++ b/roots.cpp
@@ -348,7 +348,7 @@ static int rmtree_except(const char* path, const char* except)
     return rc;
 }
 
-int format_volume(const char* volume) {
+int format_volume(const char* volume, bool force) {
     if (strcmp(volume, "media") == 0) {
         if (!vdc->isEmulatedStorage()) {
             return 0;
@@ -378,7 +378,7 @@ int format_volume(const char* volume) {
         return -1;
     }
 
-    if (strcmp(volume, "/data") == 0 && vdc->isEmulatedStorage()) {
+    if (!force && strcmp(volume, "/data") == 0 && vdc->isEmulatedStorage()) {
         if (ensure_path_mounted("/data") == 0) {
             // Preserve .layout_version to avoid "nesting bug"
             LOGI("Preserving layout version\n");
diff --git a/roots.h b/roots.h
index 9b369c0..addb142 100644
--- a/roots.h
+++ b/roots.h
@@ -42,7 +42,7 @@ int ensure_path_unmounted(const char* path, bool detach=false);
 // Reformat the given volume (must be the mount point only, eg
 // "/cache"), no paths permitted.  Attempts to unmount the volume if
 // it is mounted.
-int format_volume(const char* volume);
+int format_volume(const char* volume, bool force = false);
 
 // Ensure that all and only the volumes that packages expect to find
 // mounted (/tmp and /cache) are mounted.  Returns 0 on success.