Revert "Revert "ota: Make sure we don't install on top of an incompat…

…ible system""

This should be fixed now.

This reverts commit 5875e34.

Change-Id: Ie102ff6ecb08bff80c83654a490fd18248d23086

tools/releasetools/edify_generator.py

@@ -122,6 +122,17 @@ def RunBackup(self, command):
         self.script.append('delete("/system/bin/backuptool.sh");')
         self.script.append('delete("/system/bin/backuptool.functions");')
 
+  def ValidateSignatures(self, command):
+    if command == "cleanup":
+        self.script.append('delete("/system/bin/otasigcheck.sh");')
+    else:
+        self.script.append('package_extract_file("system/bin/otasigcheck.sh", "/tmp/otasigcheck.sh");')
+        self.script.append('package_extract_file("META-INF/org/cyanogenmod/releasekey", "/tmp/releasekey");')
+        self.script.append('set_metadata("/tmp/otasigcheck.sh", "uid", 0, "gid", 0, "mode", 0755);')
+        self.script.append('run_program("/tmp/otasigcheck.sh");')
+        ## Hax: a failure from run_program doesn't trigger an abort, so have it change the key value and check for "INVALID"
+        self.script.append('sha1_check(read_file("/tmp/releasekey"),"7241e92725436afc79389d4fc2333a2aa8c20230") && abort("Can\'t install this package on top of incompatible data. Please try another package or run a factory reset");')
+
   def ShowProgress(self, frac, dur):
     """Update the progress bar, advancing it over 'frac' over the next
     'dur' seconds.  'dur' may be zero to advance it via SetProgress

tools/releasetools/ota_from_target_files

@@ -511,6 +511,10 @@ else if get_stage("%(bcb_dev)s", "stage") == "3/3" then
 
   device_specific.FullOTA_InstallBegin()
 
+  script.Mount("/data")
+  script.ValidateSignatures("data")
+  script.Unmount("/data")
+
   if OPTIONS.backuptool:
     script.Mount("/system")
     script.RunBackup("backup")
@@ -545,6 +549,8 @@ else if get_stage("%(bcb_dev)s", "stage") == "3/3" then
   common.ZipWriteStr(output_zip, "boot.img", boot_img.data)
   script.ShowProgress(0.2, 0)
 
+  script.ValidateSignatures("cleanup")
+
   if OPTIONS.backuptool:
     script.ShowProgress(0.2, 10)
     script.RunBackup("restore")