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authorSimon Glass <sjg@chromium.org>2013-06-13 15:10:07 -0700
committerTom Rini <trini@ti.com>2013-06-26 10:18:56 -0400
commit399c744b22459585dc2dda2cb7353b3026e28e18 (patch)
tree82c9fe00fe92fd0eea8831a8224fcad3cac09aad /doc
parent4f6104270146c76fcaf46e951f84cdc1612a04b7 (diff)
mkimage: Add -r option to specify keys that must be verified
Normally, multiple public keys can be provided and U-Boot is not required to use all of them for verification. This is because some images may not be signed, or may be optionally signed. But we still need a mechanism to determine when a key must be used. This feature cannot be implemented in the FIT itself, since anyone could change it to mark a key as optional. The requirement for key verification must go in with the public keys, in a place that is protected from modification. Add a -r option which tells mkimage to mark all keys that it uses for signing as 'required'. If some keys are optional and some are required, run mkimage several times (perhaps with different key directories if some keys are very secret) using the -F flag to update an existing FIT. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Marek Vasut <marex@denx.de>
Diffstat (limited to 'doc')
-rw-r--r--doc/mkimage.16
1 files changed, 6 insertions, 0 deletions
diff --git a/doc/mkimage.1 b/doc/mkimage.1
index b67a35178a0..14374da88af 100644
--- a/doc/mkimage.1
+++ b/doc/mkimage.1
@@ -133,6 +133,12 @@ the corresponding public key is written into this file for for run-time
verification. Typically the file here is the device tree binary used by
CONFIG_OF_CONTROL in U-Boot.
+.TP
+.BI "\-r
+Specifies that keys used to sign the FIT are required. This means that they
+must be verified for the image to boot. Without this option, the verification
+will be optional (useful for testing but not for release).
+
.SH EXAMPLES
List image information: