Introduce a QCryptoTLSSession object that will encapsulate
all the code for setting up and using a client/sever TLS
session. This isolates the code which depends on the gnutls
library, avoiding #ifdefs in the rest of the codebase, as
well as facilitating any possible future port to other TLS
libraries, if desired. It makes use of the previously
defined QCryptoTLSCreds object to access credentials to
use with the session. It also includes further unit tests
to validate the correctness of the TLS session handshake
and certificate validation. This is functionally equivalent
to the current TLS session handling code embedded in the
VNC server, and will obsolete it.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If the administrator incorrectly sets up their x509 certificates,
the errors seen at runtime during connection attempts are very
obscure and difficult to diagnose. This has been a particular
problem for people using openssl to generate their certificates
instead of the gnutls certtool, because the openssl tools don't
turn on the various x509 extensions that gnutls expects to be
present by default.
This change thus adds support in the TLS credentials object to
sanity check the certificates when QEMU first loads them. This
gives the administrator immediate feedback for the majority of
common configuration mistakes, reducing the pain involved in
setting up TLS. The code is derived from equivalent code that
has been part of libvirt's TLS support and has been seen to be
valuable in assisting admins.
It is possible to disable the sanity checking, however, via
the new 'sanity-check' property on the tls-creds object type,
with a value of 'no'.
Unit tests are included in this change to verify the correctness
of the sanity checking code in all the key scenarios it is
intended to cope with. As part of the test suite, the pkix_asn1_tab.c
from gnutls is imported. This file is intentionally copied from the
(long since obsolete) gnutls 1.6.3 source tree, since that version
was still under GPLv2+, rather than the GPLv3+ of gnutls >= 2.0.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Introduce a QCryptoTLSCredsX509 class which is used to
manage x509 certificate TLS credentials. This will be
the preferred credential type offering strong security
characteristics
Example CLI configuration:
$QEMU -object tls-creds-x509,id=tls0,endpoint=server,\
dir=/path/to/creds/dir,verify-peer=yes
The 'id' value in the -object args will be used to associate the
credentials with the network services. For example, when the VNC
server is later converted it would use
$QEMU -object tls-creds-x509,id=tls0,.... \
-vnc 127.0.0.1:1,tls-creds=tls0
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Introduce a QCryptoTLSCredsAnon class which is used to
manage anonymous TLS credentials. Use of this class is
generally discouraged since it does not offer strong
security, but it is required for backwards compatibility
with the current VNC server implementation.
Simple example CLI configuration:
$QEMU -object tls-creds-anon,id=tls0,endpoint=server
Example using pre-created diffie-hellman parameters
$QEMU -object tls-creds-anon,id=tls0,endpoint=server,\
dir=/path/to/creds/dir
The 'id' value in the -object args will be used to associate the
credentials with the network services. For example, when the VNC
server is later converted it would use
$QEMU -object tls-creds-anon,id=tls0,.... \
-vnc 127.0.0.1:1,tls-creds=tls0
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Introduce a QCryptoTLSCreds class to act as the base class for
storing TLS credentials. This will be later subclassed to provide
handling of anonymous and x509 credential types. The subclasses
will be user creatable objects, so instances can be created &
deleted via 'object-add' and 'object-del' QMP commands respectively,
or via the -object command line arg.
If the credentials cannot be initialized an error will be reported
as a QMP reply, or on stderr respectively.
The idea is to make it possible to represent and manage TLS
credentials independently of the network service that is using
them. This will enable multiple services to use the same set of
credentials and minimize code duplication. A later patch will
convert the current VNC server TLS code over to use this object.
The representation of credentials will be functionally equivalent
to that currently implemented in the VNC server with one exception.
The new code has the ability to (optionally) load a pre-generated
set of diffie-hellman parameters, if the file dh-params.pem exists,
whereas the current VNC server will always generate them on startup.
This is beneficial for admins who wish to avoid the (small) time
sink of generating DH parameters at startup and/or avoid depleting
entropy.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Introduce a generic cipher API and an implementation of it that
supports only the built-in AES and DES-RFB algorithms.
The test suite checks the supported algorithms + modes to
validate that every backend implementation is actually correctly
complying with the specs.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-5-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To prepare for a generic internal cipher API, move the
built-in D3DES implementation into the crypto/ directory.
This is not in fact a normal D3DES implementation, it is
D3DES with double & triple length modes removed, and the
key bytes in reversed bit order. IOW it is crippled
specifically for the "benefit" of RFB, so call the new
files desrfb.c instead of d3des.c to make it clear that
it isn't a generally useful impl.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
To prepare for a generic internal cipher API, move the
built-in AES implementation into the crypto/ directory
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-3-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>
