• Antonio Nino Diaz's avatar
    tbbr: Use constant-time bcmp() to compare hashes · b621fb50
    Antonio Nino Diaz authored
    
    
    To avoid timing side-channel attacks, it is needed to use a constant
    time memory comparison function when comparing hashes. The affected
    code only cheks for equality so it isn't needed to use any variant of
    memcmp(), bcmp() is enough.
    
    Also, timingsafe_bcmp() is as fast as memcmp() when the two compared
    regions are equal, so this change incurrs no performance hit in said
    case. In case they are unequal, the boot sequence wouldn't continue as
    normal, so performance is not an issue.
    
    Change-Id: I1c7c70ddfa4438e6031c8814411fef79fd3bb4df
    Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
    b621fb50
mbedtls_crypto.c 6.14 KB