The default (required) identity is stored in server-cert.pem /
client-cert.pem and server-key.pem / client-key.pem.
The 4 extra (optional) identities are stored in server-cert-$N.pem /
client-cert-$N.pem and server-key-$N.pem / client-key-$N.pem. The
numbering starts at 0 and the first missing cert/key pair will
terminate the loading process.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Currently only a single set of certificates can be loaded for a
server / client. Certificates are created using a particular
key algorithm and in some scenarios it can be useful to support
multiple algorithms in parallel. This requires the ability to
load multiple sets of certificates.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The x509 TLS credentials code will load the identity certs once to
perform sanity chcking on the certs, then discard the certificate
objects and let gnutls load them a second time.
This extends the previous QCryptoTLSCredsX509Files struct to also
hold the identity certificates & key loaded for sanity checking
and pass them on to gnutls, avoiding the duplicated loading.
The unit tests need updating because we now correctly diagnose the
error scenario where the cert PEM file exists, without its matching
key PEM file. Previously that error was mistakenly ignored.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The x509 TLS credentials code will load the CA certs once to perform
sanity chcking on the certs, then discard the certificate objects
and let gnutls load them a second time.
This introduces a new QCryptoTLSCredsX509Files struct which will
hold the CA certificates loaded for sanity checking and pass them on
to gnutls, avoiding the duplicated loading.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
GNUTLS has deprecated use of externally provided diffie-hellman
parameters. Since 3.6.0 it will automatically negotiate DH params
in accordance with RFC7919.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Now that the TLS session code no longer needs to look at the TLS
credential structs, they can be made private.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
As described in the previous commit, the gnutls credentials need to
be kept alive for as long as the gnutls session object exists. Convert
the QCryptoTLSCreds objects to use QCryptoTLSCredsBox and holding the
gnutls credential objects. When loading the credentials into a gnutls
session, store a reference to the box into the QCryptoTLSSession object.
This has the useful side effect that the QCryptoTLSSession code no
longer needs to know about all the different credential types, it can
use the generic pointer stored in the box.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The gnutls_credentials_set() method has a very suprising API contract
that requires the caller to preserve the passed in credentials pointer
for as long as the gnutls_session_t object is alive. QEMU is failing
to ensure this happens.
In QEMU the GNUTLS credentials object is owned by the QCryptoTLSCreds
object instance while the GNUTLS session object is owned by the
QCryptoTLSSession object instance. Their lifetimes are not guaranteed
to be the same, though in most common usage the credentials will outlive
the session. This is notably not the case, however, after the VNC server
gained the ability to reload credentials on the fly with:
commit 1f08e34151
Author: Zihao Chang <changzihao1@huawei.com>
Date: Tue Mar 16 15:58:44 2021 +0800
vnc: support reload x509 certificates for vnc
If that is triggered while a VNC client is in the middle of performing
a TLS handshake, we might hit a use-after-free.
It is difficult to correct this problem because there's no way to deep-
clone a GNUTLS credentials object, nor is it reference counted. Thus we
introduce a QCryptoTLSCredsBox object whose only purpose is to add
reference counting around the GNUTLS credentials object.
The DH parameters set against a credentials object also have to be kept
alive for as long as the credentials exist. So the box must also hold
the DH parameters pointer.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This prevents direct access of the class members by the VNC
display code.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The logic for setting the TLS priority string on a session object has a
significant amount of logic duplication across the different credential
types. By recording the extra priority string suffix against the
credential class, we can introduce a common method for building the
priority string. The TLS session can now set the priority string without
caring about the credential type.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The code for releasing DH parameters is common to all credential
subclasses, and the unload function is only called from the
finalizers, except for x509 reload, so can be moved into the
parent with a little update of the reload method.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The reload method already has a pointer to the parent object in
the 'creds' parameter that is passed in, so indirect access via
the subclass 'parent_obj' field is redundant.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This allows removal of goto jumps during loading of the credentials
and will simplify the diff in following commits.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The check for the 'dir' property is being repeated for every
credential file to be loaded, but this results in incorrect
logic for optional credentials. The 'dir' property is mandatory
for PSK and x509 creds, even if some individual files are
optional. Address this by separating the check for the 'dir'
property.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The qcrypto_tls_creds_get_path method will perform an access()
check on the file and return a NULL path if it fails. By the
time we get to loading the cert files we know they must exist
on disk and thus the second access() check is redundant.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Readability of the credential files is what matters for our usage,
so access() is more appropriate than stat().
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The only caller of qcrypto_tls_creds_check_authority_chain always
passes 'true' for the 'isCA' parameter. The point of this method
is to check the CA chani, so no other value would ever make sense.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
nettle included XTS in 3.4.1, so with the new min version we
no longer require the in-tree XTS cipher mode impl.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The XTS support required 3.6.8 which is older than our min
required version now.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Cryptographic hash function can operate on any area of memory,
regardless of the content their represent. Do not restrict to
array of char, use the void* type, which is also the type of
the underlying iovec::iov_base field.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The new API automatically allocates the right amount of memory
to hold the distinguished name, avoiding the need to loop and
realloc.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Daniel P. Berrangé
Philippe Mathieu-DaudéandDaniel P. Berrangé