secure_erase_file: Create secure_erase_file tool.
This commit introduces a library and binary for securely erasing files
that are backed by eMMC storage.
This change uses BLKDISCARD, which is translated by the kernel to
either an eMMC "Secure Trim" or "Secure Erase" command, depending on the
request length.
Followup changes will
* create an ebuild package,
* add an autotest-based integration test,
* add binary uses in platform2/init/clobber-state, and
* add library uses in platform2/cryptohome.
BUG=chromium:718518
TEST=manually tested on caroline, eve, also tested with platform_SecureErase
Change-Id: I5252997993072b479be37d57d971ec66934c1594
Reviewed-on: https://chromium-review.googlesource.com/498647
Commit-Ready: Justin TerAvest <teravest@chromium.org>
Tested-by: Justin TerAvest <teravest@chromium.org>
Reviewed-by: Justin TerAvest <teravest@chromium.org>
6 files changed
