The SHA-1 algorithm is considered a weak hash algorithm and there has been
some movement within certain distros to drop its support completely or at
least drop it from the default behavior. ima-evm-utils uses it as the
default algorithm in case the user doesn't explicitly ask for another
through the --with-default-hash configuration time option or --hashalgo/-a
runtime option. With that, make SHA-256 the default hash algorithm instead.
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
The default hash algorithm for evmctl is today hardcoded in the libimaevm.c
file. To facilitate package maintainers across different distributions to
set their own default hash algorithm, this patch adds the
--with-default-hash=<algo> option to the configuration script.
The chosen algorithm will then be checked by its available in the kernel,
otherwise IMA won't be able to verify files hashed by the user. For that,
the kernel header hash_info.h used as the source of supported hashes. In
case the hash_info.h header is not present, the configuration script warns
about it, but uses whatever the user specified in the option.
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
