From cee206880ef80ac570df6b369d12f111c00f653a Mon Sep 17 00:00:00 2001
From: JP Abgrall <jpa@google.com>
Date: Wed, 2 Jul 2014 14:26:54 -0700
Subject: [PATCH] [HACK]fs_mgr+init: Format via recovery if encryptable /data
 is wiped

If the encryptable partition is wiped (4KB worth of 0 or 0xff),
then reboot into recovery to format /data+/cache

This is while waiting for the Mac OS support to format f2fs.
The flashstation running on Mac OS will currently just erase userdata
and not format it with f2fs.

Bug: 15720406
Bug: 15747366
Change-Id: Ib7cca3e1701483a09573457a835750f34da71ee0
---
 fs_mgr/fs_mgr.c         | 10 ++++++----
 fs_mgr/include/fs_mgr.h |  1 +
 init/builtins.c         | 27 +++++++++++++++++++++++++++
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/fs_mgr/fs_mgr.c b/fs_mgr/fs_mgr.c
index f01c56207..3f94af5e7 100644
--- a/fs_mgr/fs_mgr.c
+++ b/fs_mgr/fs_mgr.c
@@ -387,10 +387,12 @@ int fs_mgr_mount_all(struct fstab *fstab)
 
         /* mount(2) returned an error, check if it's encryptable and deal with it */
         if (mret && mount_errno != EBUSY && mount_errno != EACCES &&
-            fs_mgr_is_encryptable(&fstab->recs[i])) {
-            if (partition_wiped(fstab->recs[i].blk_device)) {
-                ERROR("%s(): Encryptable wiped partition %s. Recommend wiping via recovery. Fail for now.\n", __func__, fstab->recs[i].mount_point);
-                ++error_count;
+            fs_mgr_is_encryptable(&fstab->recs[attempted_idx])) {
+            if(partition_wiped(fstab->recs[attempted_idx].blk_device)) {
+                ERROR("%s(): %s is wiped and %s %s is encryptable. Suggest recovery...\n", __func__,
+                      fstab->recs[attempted_idx].blk_device, fstab->recs[attempted_idx].mount_point,
+                      fstab->recs[attempted_idx].fs_type);
+                encryptable = FS_MGR_MNTALL_DEV_NEEDS_RECOVERY;
                 continue;
             } else {
                 /* Need to mount a tmpfs at this mountpoint for now, and set
diff --git a/fs_mgr/include/fs_mgr.h b/fs_mgr/include/fs_mgr.h
index ab3f82844..d9c58d4fe 100644
--- a/fs_mgr/include/fs_mgr.h
+++ b/fs_mgr/include/fs_mgr.h
@@ -54,6 +54,7 @@ struct fstab_rec {
 struct fstab *fs_mgr_read_fstab(const char *fstab_path);
 void fs_mgr_free_fstab(struct fstab *fstab);
 
+#define FS_MGR_MNTALL_DEV_NEEDS_RECOVERY 3
 #define FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION 2
 #define FS_MGR_MNTALL_DEV_MIGHT_BE_ENCRYPTED 1
 #define FS_MGR_MNTALL_DEV_NOT_ENCRYPTED 0
diff --git a/init/builtins.c b/init/builtins.c
index dd147f603..f7bd8a997 100644
--- a/init/builtins.c
+++ b/init/builtins.c
@@ -474,6 +474,26 @@ exit_success:
 
 }
 
+static int wipe_data_via_recovery()
+{
+    mkdir("/cache/recovery", 0700);
+    int fd = open("/cache/recovery/command", O_RDWR|O_CREAT|O_TRUNC, 0600);
+    if (fd >= 0) {
+        write(fd, "--wipe_data", strlen("--wipe_data") + 1);
+        close(fd);
+    } else {
+        ERROR("could not open /cache/recovery/command\n");
+        return -1;
+    }
+    android_reboot(ANDROID_RB_RESTART2, 0, "recovery");
+    while (1) { pause(); }  // never reached
+}
+
+
+/*
+ * This function might request a reboot, in which case it will
+ * not return.
+ */
 int do_mount_all(int nargs, char **args)
 {
     pid_t pid;
@@ -529,6 +549,13 @@ int do_mount_all(int nargs, char **args)
          * that action.
          */
         action_for_each_trigger("nonencrypted", action_add_queue_tail);
+    } else if (ret == FS_MGR_MNTALL_DEV_NEEDS_RECOVERY) {
+        /* Setup a wipe via recovery, and reboot into recovery */
+        ERROR("fs_mgr_mount_all suggested recovery, so wiping data via recovery.\n");
+        ret = wipe_data_via_recovery();
+        /* If reboot worked, there is no return. */
+    } else if (ret > 0) {
+        ERROR("fs_mgr_mount_all returned unexpected error %d\n", ret);
     }
     /* else ... < 0: error */