The AppArmor security driver adds only the path specified in the domain
XML for character devices of type 'pipe'. It should be using <path>.in
and <path>.out. We do this by creating a new vah_add_file_chardev() and
use it for char devices instead of vah_add_file(). Also adjust
valid_path() to accept S_FIFO (since qemu chardevs of type 'pipe' use
fifos). This is https://launchpad.net/bugs/832507
In the Ubuntu development release we recently got a new udev that
moves /var/run to /run, /var/lock to /run/lock and /dev/shm to /run/shm.
This change in udev requires updating the apparmor security driver in
libvirt[1].
Attached is a patch that:
* adjusts src/security/virt-aa-helper.c to allow both
LOCALSTATEDIR/run/libvirt/**/%s.pid and /run/libvirt/**/%s.pid. While
the profile is not as precise, LOCALSTATEDIR/run/ is typically a symlink
to /run/ anyway, so there is no additional access (remember that
apparmor resolves symlinks, which is why this is still required even
if /var/run points to /run).
* adjusts example/apparmor/libvirt-qemu paths for /dev/shm
[1]https://launchpad.net/bugs/810270
--
Jamie Strandboge | http://www.canonical.com
Commit 12317957ec introduced an incompatible
architectural change for the AppArmor security driver. Specifically,
virSecurityManagerSetAllLabel() is now called much later in
src/qemu/qemu_process.c:qemuProcessStart(). Previously, SetAllLabel() was
called immediately after GenLabel() such that after the dynamic label (profile
name) was generated, SetAllLabel() would be called to create and load the
AppArmor profile into the kernel before qemuProcessHook() was executed. With
12317957ec, qemuProcessHook() is now called
before SetAllLabel(), such that aa_change_profile() ends up being called
before the AppArmor profile is loaded into the kernel (via ProcessLabel() in
qemuProcessHook()).
This patch addresses the change by making GenLabel() load the AppArmor
profile into the kernel after the label (profile name) is generated.
SetAllLabel() is then adjusted to only reload_profile() and append stdin_fn to
the profile when it is specified. This also makes the AppArmor driver work
like its SELinux counterpart with regard to SetAllLabel() and stdin_fn.
Bug-Ubuntu: https://launchpad.net/bugs/801569
During a savevm operation, libvirt will now use fd migration if qemu
supports it. When the AppArmor driver is enabled, AppArmorSetFDLabel()
is used but since this function simply returns '0', the dynamic AppArmor
profile is not updated and AppArmor blocks access to the save file. This
patch implements AppArmorSetFDLabel() to get the pathname of the file by
resolving the fd symlink in /proc, and then gives that pathname to
reload_profile(), which fixes 'virsh save' when AppArmor is enabled.
Reference: https://launchpad.net/bugs/795800
When <uuid> is not in the XML, a virUUIDGenerate() ends up being called which
is unnecessary and can lead to crashes if /dev/urandom isn't available
because virRandomInitialize() is not called within virt-aa-helper. This patch
adds verify_xpath_context() and updates caps_mockup() to use it.
Bug-Ubuntu: https://launchpad.net/bugs/672943
Description: Implement AppArmorSetSecurityHostdevLabel() and
AppArmorRestoreSecurityHostdevLabel() for hostdev and pcidev attach.
virt-aa-helper also has to be adjusted because *FileIterate() is used for pci
and usb devices and the corresponding XML for hot attached hostdev and pcidev
is not in the XML passed to virt-aa-helper. The new '-F filename' option is
added to append a rule to the profile as opposed to the existing '-f
filename', which rewrites the libvirt-<uuid>.files file anew. This new '-F'
option will append a rule to an existing libvirt-<uuid>.files if it exists,
otherwise it acts the same as '-f'.
load_profile() and reload_profile() have been adjusted to add an 'append'
argument, which when true will use '-F' instead of '-f' when executing
virt-aa-helper.
All existing calls to load_profile() and reload_profile() have been adjusted
to use the old behavior (ie append==false) except AppArmorSetSavedStateLabel()
where it made sense to use the new behavior.
This patch also adds tests for '-F'.
Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/640993
Description: Check for VIR_DOMAIN_CHR_TYPE in serial ports and add 'rw' for
defined serial ports, parallel ports and channels
Bug-Ubuntu: LP: #578527, LP: #609055
Adjust args to qemudStartVMDaemon() to also specify path to stdin_fd,
so this can be passed to the AppArmor driver via SetSecurityAllLabel().
This updates all calls to qemudStartVMDaemon() as well as setting up
the non-AppArmor security driver *SetSecurityAllLabel() declarations
for the above. This is required for the following
"apparmor-fix-save-restore" patch since AppArmor resolves the passed
file descriptor to the pathname given to open().
* src/security/virt-aa-helper.c: adjust virt-aa-helper to handle pci
devices. Update valid_path() to have an override array to check against,
and add "/sys/devices/pci" to it. Then rename file_iterate_cb() to
file_iterate_hostdev_cb() and create file_iterate_pci_cb() based on it
To avoid an error when hitting the <seclabel...> definition
* src/security/virt-aa-helper.c: add VIR_DOMAIN_XML_INACTIVE flag
to virDomainDefParseString
Don't exit with error if the user unloaded the profile outside of
libvirt
* src/security/virt-aa-helper.c: check the exit error from apparmor_parser
before exiting with a failure
The calls to virExec() in security_apparmor.c when
invoking virt-aa-helper use VIR_EXEC_CLEAR_CAPS. When compiled without
libcap-ng, this is not a problem (it's effectively a no-op) but with
libcap-ng this causes MAC_ADMIN to be cleared. MAC_ADMIN is needed by
virt-aa-helper to manipulate apparmor profiles and without it VMs will
not start[1]. This patch calls virExec with the default VIR_EXEC_NONE
instead.
* src/security/security_apparmor.c: fallback to VIR_EXEC_NONE flags for
virExec of virt_aa_helper
tests/virt-aa-helper-test and examples/apparmor are not included in
official tarballs, but should be. Attached is a patch to fix that
which works when apparmor is and is not available.
Fixes https://launchpad.net/bugs/453335
* src/security/virt-aa-helper.c: suppress confusing and misleading
apparmor denied message when kvm/qemu tries to open a libvirt specified
readonly file (such as a cdrom) with write permissions. libvirt uses
the readonly attribute for the security driver only, and has no way
of telling kvm/qemu that the device should be opened readonly
Fixes https://launchpad.net/bugs/460271
* src/security/virt-aa-helper.c: require absolute path for dynamic added
files. This is required by AppArmor and conveniently prevents adding
tcp consoles to the profile
* examples/apparmor/libvirt-qemu: adds pulseaudio, alsa and preliminary
save/restore to the example apparmor abstraction
* examples/apparmor/usr.sbin.libvirtd: allows libvirtd access to inet
dgram, inet6 dgram, inet6 stream and /usr/lib/libvirt/*
* src/security/virt-aa-helper.c: get_definition() now calls the new
caps_mockup() function which will parse the XML for os.type,
os.type.arch and then sets the wordsize. These attributes are needed
only to get a valid virCapsPtr for virDomainDefParseString(). The -H
and -b options are now removed from virt-aa-helper (they weren't used
yet anyway).
* tests/virt-aa-helper-test: extend and fixes tests, chmod'ed 755
* docs/drvqemu.html.in: include documentation for AppArmor sVirt
confinement
* examples/apparmor/TEMPLATE examples/apparmor/libvirt-qemu
examples/apparmor/usr.lib.libvirt.virt-aa-helper
examples/apparmor/usr.sbin.libvirtd: example templates and
configuration files for SVirt Apparmor when using KVM/QEmu
* configure.in: look for AppArmor and devel
* src/security/security_apparmor.[ch] src/security/security_driver.c
src/Makefile.am: add and plug the new driver
* src/security/virt-aa-helper.c: new binary which is used exclusively by
the AppArmor security driver to manipulate AppArmor.
* po/POTFILES.in: registers the new files
* tests/Makefile.am tests/secaatest.c tests/virt-aa-helper-test:
tests for virt-aa-helper and the security driver, secaatest.c is
identical to seclabeltest.c except it initializes the 'apparmor'
driver instead of 'selinux'
When James Morris originally submitted his sVirt patches (as seen in
libvirt 0.6.1), he did not require on disk labelling for
virSecurityDomainRestoreImageLabel. A later commit[2] changed this
behavior to assume on disk labelling, which halts implementations for
path-based MAC systems such as AppArmor and TOMOYO where
vm->def->seclabel is required to obtain the label.
* src/security/security_driver.h src/qemu/qemu_driver.c
src/security/security_selinux.c: adds the 'virDomainObjPtr vm'
argument back to *RestoreImageLabel
Jamie Strandboge
Jamie Strandboge