1. 31 Jan, 2017 1 commit
  2. 15 Dec, 2016 1 commit
    • dp-arm's avatar
      tbbr: Fix updating of Non-Trusted NV counter · d35dee23
      dp-arm authored
      
      
      The previous code required that a certificate be signed with the ROT
      key before the platform's NV counter could be updated with the value
      in the certificate.  This implies that the Non-Trusted NV counter was
      not being updated for Non-Trusted content certificates, as they cannot
      be signed with the ROT key in the TBBR CoT scheme.
      
      The code is reworked to only allow updating the platform's Trusted NV
      counter when a certificate protected by the Trusted NV counter is
      signed with the ROT key.
      
      Content certificates protected by the Non-Trusted NV counter are
      allowed to update the platform's Non-Trusted NV counter, assuming
      that the certificate value is higher than the platform's value.
      
      A new optional platform API has been introduced, named
      plat_set_nv_ctr2().  Platforms may choose to implement it and perform
      additional checks based on the authentication image descriptor before
      modifying the NV counters.  A default weak implementation is available
      that just calls into plat_set_nv_ctr().
      
      Fixes ARM-software/tf-issues#426
      
      Change-Id: I4fc978fd28a3007bc0cef972ff1f69ad0413b79c
      Signed-off-by: default avatardp-arm <dimitris.papastamos@arm.com>
      d35dee23