Make use of the QCryptoSecret object to support loading of
encrypted x509 keys. The optional 'passwordid' parameter
to the tls-creds-x509 object type, provides the ID of a
secret object instance that holds the decryption password
for the PEM file.
# printf "123456" > mypasswd.txt
# $QEMU \
-object secret,id=sec0,filename=mypasswd.txt \
-object tls-creds-x509,passwordid=sec0,id=creds0,\
dir=/home/berrange/.pki/qemu,endpoint=server \
-vnc :1,tls-creds=creds0
This requires QEMU to be linked to GNUTLS >= 3.1.11. If
GNUTLS is too old an error will be reported if an attempt
is made to pass a decryption password.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
In qcrypto_tls_creds_get_path() coverity complains that
we are checking '*creds' for NULL, despite having
dereferenced it previously. This is harmless bug due
to fact that the trace call was too early. Moving it
after the cleanup gets the desired semantics.
In qcrypto_tls_creds_check_cert_key_purpose() coverity
complains that we're passing a pointer to a previously
free'd buffer into gnutls_x509_crt_get_key_purpose_oid()
This is harmless because we're passing a size == 0, so
gnutls won't access the buffer, but rather just report
what size it needs to be. We can avoid it though by
explicitly setting the buffer to NULL after free'ing
it.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The qcrypto_tls_creds_x509_sanity_check() checks whether
certs exist by calling access(). It is valid for this
method to be invoked with certfile==NULL though, since
for client credentials the cert is optional. This caused
it to call access(NULL), which happens to be harmless on
current Linux, but should none the less be avoided.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The QCryptoTLSCredsX509 object was not free'ing the allocated
gnutls_dh_params_t data when unloading the credentials
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>
Daniel P. Berrange