Commit Graph

11 Commits

Author SHA1 Message Date
Markus Armbruster 8e26ae7bb5 authz-list-file: Improve an error message
When qauthz_list_file_load() rejects JSON values other than JSON
object with a rather confusing error message:

    $ echo 1 | qemu-system-x86_64 -nodefaults -S -display none  -object authz-list-file,id=authz0,filename=/dev/stdin
    qemu-system-x86_64: -object authz-list-file,id=authz0,filename=/dev/stdin: Invalid parameter type for 'obj', expected: dict

Improve to

    qemu-system-x86_64: -object authz-list-file,id=authz0,filename=/dev/stdin: File '/dev/stdin' must contain a JSON object

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-18 10:51:35 +00:00
Markus Armbruster 2b37e9f843 authz-list-file: Fix file read error handling
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.

qauthz_list_file_complete() is wrong that way: it passes @errp to
qauthz_list_file_complete() without checking for failure.  If it runs
into another failure, it trips error_setv()'s assertion.  Reproducer:

    $ qemu-system-x86_64 -nodefaults -S -display none -object authz-list-file,id=authz0,filename=
    qemu-system-x86_64: ../util/error.c:59: error_setv: Assertion `*errp == NULL' failed.
    Aborted (core dumped)

Fix it to check for failure.

Fixes: 55d869846d
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-18 10:51:35 +00:00
Chetan Pant 036a80cdf7 authz: Fix Lesser GPL version number
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.

Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-10-29 09:57:37 +00:00
Eduardo Habkost 14b3948536 authz-list-file: Fix crash when filename is not set
Fix the following crash:

  $ qemu-system-x86_64 -object authz-list-file,id=obj0
  qemu-system-x86_64: -object authz-list-file,id=obj0: GLib: g_file_get_contents: assertion 'filename != NULL' failed
  Segmentation fault (core dumped)

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Message-Id: <20201008202713.1416823-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-10-13 15:56:30 -04:00
Eduardo Habkost c734cd40a1 qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE
The requirement to specify the parent class type makes the macro
harder to use and easy to misuse (silent bugs can be introduced
if the wrong struct type is specified).

Simplify the macro by just not declaring any class struct,
allowing us to remove the class_size field from the TypeInfo
variables for those types.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200916182519.415636-3-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Markus Armbruster d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00
Jafar Abdi 834e8bf17c authz: fix usage of bool in listfile.c
Clean up wrong usage of FALSE and TRUE in places that use "bool" from stdbool.h.

FALSE and TRUE (with capital letters) are the constants defined by glib for
being used with the "gboolean" type of glib. But some parts of the code also use
TRUE and FALSE for variables that are declared as "bool" (the type from <stdbool.h>).

Signed-off-by: Jafar Abdi <cafer.abdi@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-02-07 12:22:19 +00:00
Markus Armbruster 0b8fa32f55 Include qemu/module.h where needed, drop it from qemu-common.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-4-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c
hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c;
ui/cocoa.m fixed up]
2019-06-12 13:18:33 +02:00
Markus Armbruster 45b1f68ca5 authz: Normalize #include "authz/trace.h" to "trace.h"
Include the generated trace.h the same way as we do everywhere else.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190315145123.28030-3-armbru@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-05-13 08:58:55 +02:00
Daniel P. Berrangé b4682a63f8 filemon: fix watch IDs to avoid potential wraparound issues
Watch IDs are allocated from incrementing a int counter against
the QFileMonitor object. In very long life QEMU processes with
a huge amount of USB MTP activity creating & deleting directories
it is just about conceivable that the int counter can wrap
around. This would result in incorrect behaviour of the file
monitor watch APIs due to clashing watch IDs.

Instead of trying to detect this situation, this patch changes
the way watch IDs are allocated. It is turned into an int64_t
variable where the high 32 bits are set from the underlying
inotify "int" ID. This gives an ID that is guaranteed unique
for the directory as a whole, and we can rely on the kernel
to enforce this. QFileMonitor then sets the low 32 bits from
a per-directory counter.

The USB MTP device only sets watches on the directory as a
whole, not files within, so there is no risk of guest
triggered wrap around on the low 32 bits.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-02 13:52:02 +01:00
Daniel P. Berrangé 55d869846d authz: add QAuthZListFile object type for a file access control list
Add a QAuthZListFile object type that implements the QAuthZ interface. This
built-in implementation is a proxy around the QAuthZList object type,
initializing it from an external file, and optionally, automatically
reloading it whenever it changes.

To create an instance of this object via the QMP monitor, the syntax
used would be:

      {
        "execute": "object-add",
        "arguments": {
          "qom-type": "authz-list-file",
          "id": "authz0",
          "props": {
            "filename": "/etc/qemu/vnc.acl",
	    "refresh": true
          }
        }
      }

If "refresh" is "yes", inotify is used to monitor the file,
automatically reloading changes. If an error occurs during reloading,
all authorizations will fail until the file is next successfully
loaded.

The /etc/qemu/vnc.acl file would contain a JSON representation of a
QAuthZList object

    {
      "rules": [
         { "match": "fred", "policy": "allow", "format": "exact" },
         { "match": "bob", "policy": "allow", "format": "exact" },
         { "match": "danb", "policy": "deny", "format": "glob" },
         { "match": "dan*", "policy": "allow", "format": "exact" },
      ],
      "policy": "deny"
    }

This sets up an authorization rule that allows 'fred', 'bob' and anyone
whose name starts with 'dan', except for 'danb'. Everyone unmatched is
denied.

The object can be loaded on the comand line using

   -object authz-list-file,id=authz0,filename=/etc/qemu/vnc.acl,refresh=yes

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-02-26 15:32:18 +00:00