Currently the choice of whether to use nettle or gcrypt is
made based on what gnutls is linked to. There are times
when it is desirable to be able to force build against a
specific library. For example, if testing changes to QEMU's
crypto code all 3 possible backends need to be checked
regardless of what the local gnutls uses.
It is also desirable to be able to enable nettle/gcrypt
for cipher/hash algorithms, without enabling gnutls
for TLS support.
This gives two new configure flags, which allow the
following possibilities
Automatically determine nettle vs gcrypt from what
gnutls links to (recommended to minimize number of
crypto libraries linked to)
./configure
Automatically determine nettle vs gcrypt based on
which is installed
./configure --disable-gnutls
Force use of nettle
./configure --enable-nettle
Force use of gcrypt
./configure --enable-gcrypt
Force use of built-in AES & crippled-DES
./configure --disable-nettle --disable-gcrypt
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If we are linking to gnutls already and gnutls is built against
gcrypt, then we should use gcrypt as a cipher backend in
preference to our built-in backend.
This will be used when linking against GNUTLS 1.x and many
GNUTLS 2.x versions.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-6-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce a new crypto/ directory that will (eventually) contain
all the cryptographic related code. This initially defines a
wrapper for initializing gnutls and for computing hashes with
gnutls. The former ensures that gnutls is guaranteed to be
initialized exactly once in QEMU regardless of CLI args. The
block quorum code currently fails to initialize gnutls so it
only works by luck, if VNC server TLS is not requested. The
hash APIs avoids the need to litter the rest of the code with
preprocessor checks and simplifies callers by allocating the
correct amount of memory for the requested hash.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-2-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>