On the host OS, various aspects of TLS operation are configurable.
In particular it is possible for the sysadmin to control the TLS
cipher/protocol algorithms that applications are permitted to use.
* Any given crypto library has a built-in default priority list
defined by the distro maintainer of the library package (or by
upstream).
* The "crypto-policies" RPM (or equivalent host OS package)
provides a config file such as "/etc/crypto-policies/config",
where the sysadmin can set a high level (library-independent)
policy.
The "update-crypto-policies --set" command (or equivalent) is
used to translate the global policy to individual library
representations, producing files such as
"/etc/crypto-policies/back-ends/*.config". The generated files,
if present, are loaded by the various crypto libraries to
override their own built-in defaults.
For example, the GNUTLS library may read
"/etc/crypto-policies/back-ends/gnutls.config".
* A management application (or the QEMU user) may overide the
system-wide crypto-policies config via their own config, if
they need to diverge from the former.
Thus the priority order is "QEMU user config" > "crypto-policies
system config" > "library built-in config".
Introduce the "tls-cipher-suites" object for exposing the ordered
list of permitted TLS cipher suites from the host side to the
guest firmware, via fw_cfg. The list is represented as an array
of bytes.
The priority at which the host-side policy is retrieved is given
by the "priority" property of the new object type. For example,
"priority=@SYSTEM" may be used to refer to
"/etc/crypto-policies/back-ends/gnutls.config" (given that QEMU
uses GNUTLS).
The firmware uses the IANA_TLS_CIPHER array for configuring
guest-side TLS, for example in UEFI HTTPS Boot.
[Description from Daniel P. Berrangé, edited by Laszlo Ersek.]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200623172726.21040-2-philmd@redhat.com>
We spell out sub/dir/ in sub/dir/trace-events' comments pointing to
source files. That's because when trace-events got split up, the
comments were moved verbatim.
Delete the sub/dir/ part from these comments. Gets rid of several
misspellings.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190314180929.27722-3-armbru@redhat.com
Message-Id: <20190314180929.27722-3-armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The 'qemu_acl' type was a previous non-QOM based attempt to provide an
authorization facility in QEMU. Because it is non-QOM based it cannot be
created via the command line and requires special monitor commands to
manipulate it.
The new QAuthZ subclasses provide a superset of the functionality in
qemu_acl, so the latter can now be deleted. The HMP 'acl_*' monitor
commands are converted to use the new QAuthZSimple data type instead
in order to provide temporary backwards compatibility.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Pre-Shared Keys (PSK) is a simpler mechanism for enabling TLS
connections than using certificates. It requires only a simple secret
key:
$ mkdir -m 0700 /tmp/keys
$ psktool -u rjones -p /tmp/keys/keys.psk
$ cat /tmp/keys/keys.psk
rjones:d543770c15ad93d76443fb56f501a31969235f47e999720ae8d2336f6a13fcbc
The key can be secretly shared between clients and servers. Clients
must specify the directory containing the "keys.psk" file and a
username (defaults to "qemu"). Servers must specify only the
directory.
Example NBD client:
$ qemu-img info \
--object tls-creds-psk,id=tls0,dir=/tmp/keys,username=rjones,endpoint=client \
--image-opts \
file.driver=nbd,file.host=localhost,file.port=10809,file.tls-creds=tls0,file.export=/
Example NBD server using qemu-nbd:
$ qemu-nbd -t -x / \
--object tls-creds-psk,id=tls0,endpoint=server,dir=/tmp/keys \
--tls-creds tls0 \
image.qcow2
Example NBD server using nbdkit:
$ nbdkit -n -e / -fv \
--tls=on --tls-psk=/tmp/keys/keys.psk \
file file=disk.img
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
It is very useful to know about TLS cert verification
status when debugging, so add a trace point for it.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Move all trace-events for files in the crypto/ directory to
their own file.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1466066426-16657-4-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Philippe Mathieu-Daudé