diff --git a/signing/anti-rollback.hjson b/signing/anti-rollback.hjson new file mode 100644 index 000000000..13ca5ac26 --- /dev/null +++ b/signing/anti-rollback.hjson @@ -0,0 +1,22 @@ +// Anti-rollback version numbers. Increment these only when there is a security-relevant +// event that requires anti-rollback. In practice the maximum value of these counters is limited +// by the wear-out of the flash memory and the time it takes to set the anti-rollback counter +// to the current rollback level. So in general, we would aim for the maximum value of the counter +// to be in the "teens to dozens" count over the entire product lifetime. +// +// The 0 value is reserved to denote an uninitialized anti-rollback counter +// +// All variants of an image share the same anti-rollback counter. So, for example, dabao and baosec +// images must share a common loader/kernel anit-rollback level. This prevents a weak dabao image from +// being used to hack a baosec image. I have concerns about the scalability of this across more +// and more device types; this might have to be handled with the reserved rollback counters and/or +// reserved function codes in the future. +{ + "boot0": "1", + "boot1": "1", + "loader": "1", + "kernel": "1", + "app": "1", + "swap": "1", + "baremetal": "1" +} \ No newline at end of file