The argument (if not NULL) points to the file the domain is
restoring from. On QEMU command line this used to be '-incoming
$path', but we've switched to passing FD ages ago and thus this
argument is used only in AppArmor (which loads the profile on
domain start). Anyway, the argument does not refer to stdin,
rename it to 'incomingPath' then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
These APIs were removed/renamed in v6.5.0-rc1~142 and v6.5.0-rc1~141
because they deemed unused. And if it wasn't for the RFE [1] things
would stay that way.
The RFE asks for us to not change DAC ownership on the file a domain is
restoring from. We have been doing that for ages (if not forever),
nevertheless it's annoying because if the restore file is on an NFS
remembering owner won't help - NFS doesn't support XATTRs yet. But more
importantly, there is no need for us to chown() the file because when
restoring the domain the file is opened and the FD is then passed to
QEMU. Therefore, we really need only to set SELinux and AppArmor.
This reverts bd22eec903.
This partially reverts 4ccbd207f2.
The difference to the original code is that secdrivers are now
not required to provide dummy implementation to avoid
virReportUnsupportedError(). The callback is run if it exists, if
it doesn't zero is returned without any error.
1: https://bugzilla.redhat.com/show_bug.cgi?id=1851016
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The new name is virSecurityManagerDomainRestorePathLabel().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
After previous commit this function is used no more.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
This API allows drivers to separate out handling of @stdin_path
of virSecurityManagerSetAllLabel(). The thing is, the QEMU driver
uses transactions for virSecurityManagerSetAllLabel() which
relabels devices from inside of domain's namespace. This is what
we usually want. Except when resuming domain from a file. The
file is opened before any namespace is set up and the FD is
passed to QEMU to read the migration stream from. Because of
this, the file lives outside of the namespace and if it so
happens that the file is a block device (i.e. it lives under
/dev) its copy will be created in the namespace. But the FD that
is passed to QEMU points to the original living in the host and
not in the namespace. So relabeling the file inside the namespace
helps nothing.
But if we have a separate API for relabeling the restore file
then the QEMU driver can continue calling
virSecurityManagerSetAllLabel() with transactions enabled and
call this new API without transactions.
We already have an API for relabeling a single file
(virSecurityManagerDomainSetPathLabel()) but in case of SELinux
it uses @imagelabel (which allows RW access) and we want to use
@content_context (which allows RO access).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
In upcoming commits, virSecurityManagerSetAllLabel() will perform
rollback in case of failure by calling
virSecurityManagerRestoreAllLabel(). But in order to do that, the
former needs to have @migrated argument so that it can be passed
to the latter.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
The purpose of this API is to allow caller move XATTRs (or remove
them) from one file to another. This will be needed when moving
top level of disk chain (either by introducing new HEAD or
removing it).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Security labeling of disks consists of labeling of the disk image
itself and it's backing chain. Modify
virSecurityManager[Set|Restore]ImageLabel to take a boolean flag that
will label the full chain rather than the top image itself.
This allows to delete/unify some parts of the code and will also
simplify callers in some cases.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This introduces a syntax-check script that validates header files use a
common layout:
/*
...copyright header...
*/
<one blank line>
#ifndef SYMBOL
# define SYMBOL
....content....
#endif /* SYMBOL */
For any file ending priv.h, before the #ifndef, we will require a
guard to prevent bogus imports:
#ifndef SYMBOL_ALLOW
# error ....
#endif /* SYMBOL_ALLOW */
<one blank line>
The many mistakes this script identifies are then fixed.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When metadata locking is enabled that means the security commit
processing will be run in a fork similar to how namespaces use fork()'s
for processing. This is done to ensure libvirt can properly and
synchronously modify the metadata to store the original owner data.
Since fork()'s (e.g. virFork) have been seen as a performance bottleneck
being able to disable them allows the admin to choose whether the
performance 'hit' is worth the extra 'security' of being able to
remember the original owner of a lock.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In this patch we label the swtpm process with SELinux labels. We give it the
same label as the QEMU process has. We label its state directory and files
as well. We restore the old security labels once the swtpm has terminated.
The file and process labels now look as follows:
Directory: /var/lib/libvirt/swtpm
[root@localhost swtpm]# ls -lZ
total 4
rwx------. 2 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 4096 Apr 5 16:46 testvm
[root@localhost testvm]# ls -lZ
total 8
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 3648 Apr 5 16:46 tpm-00.permall
The log in /var/log/swtpm/libvirt/qemu is labeled as follows:
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 2237 Apr 5 16:46 vtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep swtpm | grep ctrl | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 tss 25664 0.0 0.0 28172 3892 ? Ss 16:57 0:00 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/testvm-swtpm.sock,mode=0660 --tpmstate dir=/var/lib/libvirt/swtpm/testvm/tpm1.2 --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep qemu | grep tpm | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 qemu 25669 99.0 0.0 3096704 48500 ? Sl 16:57 3:28 /bin/qemu-system-x86_64 [..]
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
virSecurityManagerDomainSetPathLabel is used to make a path known
to the security modules, but today is used interchangably for
- paths to files/dirs to be accessed directly
- paths to a dir, but the access will actually be to files therein
Depending on the security module it is important to know which of
these types it will be.
The argument allowSubtree augments the call to the implementations of
DomainSetPathLabel that can - per security module - decide if extra
actions shall be taken.
For now dac/selinux handle this as before, but apparmor will make
use of it to add a wildcard to the path that was passed.
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
SELinux and DAC drivers already have both functions but they were not
exported as public API of security manager.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
In the case that virtlogd is used as stdio handler we pass to QEMU
only FD to a PIPE connected to virtlogd instead of the file itself.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1430988
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
With our new qemu namespace code in place, the relabelling of
devices is done not as good is it could: a child process is
spawned, it enters the mount namespace of the qemu process and
then runs desired API of the security driver.
Problem with this approach is that internal state transition of
the security driver done in the child process is not reflected in
the parent process. While currently it wouldn't matter that much,
it is fairly easy to forget about that. We should take the extra
step now while this limitation is still fresh in our minds.
Three new APIs are introduced here:
virSecurityManagerTransactionStart()
virSecurityManagerTransactionCommit()
virSecurityManagerTransactionAbort()
The Start() is going to be used to let security driver know that
we are starting a new transaction. During a transaction no
security labels are actually touched, but rather recorded and
only at Commit() phase they are actually updated. Should
something go wrong Abort() aborts the transaction freeing up all
memory allocated by transaction.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Since its introduction in 2012 this internal API did nothing.
Moreover we have the same API that does exactly the same:
virSecurityManagerDomainSetPathLabel.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Add security driver functions to label separate storage images using the
virStorageSource definition. This will help to avoid the need to do ugly
changes to the disk struct and use the source directly.
I'm going to add functions that will deal with individual image files
rather than whole disks. Rename the security function to make room for
the new one.
I'm going to add functions that will deal with individual image files
rather than whole disks. Rename the security function to make room for
the new one.
A future patch wants the DAC security manager to be able to safely
get the supplemental group list for a given uid, but at the time
of a fork rather than during initialization so as to pick up on
live changes to the system's group database. This patch adds the
framework, including the possibility of a pre-fork callback
failing.
For now, any driver that implements a prefork callback must be
robust against the possibility of being part of a security stack
where a later element in the chain fails prefork. This means
that drivers cannot do any action that requires a call to postfork
for proper cleanup (no grabbing a mutex, for example). If this
is too prohibitive in the future, we would have to switch to a
transactioning sequence, where each driver has (up to) 3 callbacks:
PreForkPrepare, PreForkCommit, and PreForkAbort, to either clean
up or commit changes made during prepare.
* src/security/security_driver.h (virSecurityDriverPreFork): New
callback.
* src/security/security_manager.h (virSecurityManagerPreFork):
Change signature.
* src/security/security_manager.c (virSecurityManagerPreFork):
Optionally call into driver, and allow returning failure.
* src/security/security_stack.c (virSecurityDriverStack):
Wrap the handler for the stack driver.
* src/qemu/qemu_process.c (qemuProcessStart): Adjust caller.
Signed-off-by: Eric Blake <eblake@redhat.com>
The existing virSecurityManagerSetProcessLabel() API is designed so
that it must be called after forking the child process, but before
exec'ing the child. Due to the way the virCommand API works, that
means it needs to be put in a "hook" function that virCommand is told
to call out to at that time.
Setting the child process label is a basic enough need when executing
any process that virCommand should have a method of doing that. But
virCommand must be told what label to set, and only the security
driver knows the answer to that question.
The new virSecurityManagerSet*Child*ProcessLabel() API is the way to
transfer the knowledge about what label to set from the security
driver to the virCommand object. It is given a virCommandPtr, and each
security driver calls the appropriate virCommand* API to tell
virCommand what to do between fork and exec.
1) in the case of the DAC security driver, it calls
virCommandSetUID/GID() to set a uid and gid that must be set for the
child process.
2) for the SELinux security driver, it calls
virCommandSetSELinuxLabel() to save a copy of the char* that will be
sent to setexeccon_raw() *after forking the child process*.
3) for the AppArmor security drivers, it calls
virCommandSetAppArmorProfile() to save a copy of the char* that will
be sent to aa_change_profile() *after forking the child process*.
With this new API in place, we will be able to remove
virSecurityManagerSetProcessLabel() from any virCommand pre-exec
hooks.
(Unfortunately, the LXC driver uses clone() rather than virCommand, so
it can't take advantage of this new security driver API, meaning that
we need to keep around the older virSecurityManagerSetProcessLabel(),
at least for now.)
When LXC labels USB devices during hotplug, it is running in
host context, so it needs to pass in a vroot path to the
container root.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When a qemu domain is backed by huge pages, apparmor needs to grant the domain
rw access to files under the hugetlbfs mount point. Add a hook, called in
qemu_process.c, which ends up adding the read-write access through
virt-aa-helper. Qemu will be creating a randomly named file under the
mountpoint and unlinking it as soon as it has mmap()d it, therefore we
cannot predict the full pathname, but for the same reason it is generally
safe to provide access to $path/**.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
BZ:https://bugzilla.redhat.com/show_bug.cgi?id=851981
When using macvtap, a character device gets first created by
kernel with name /dev/tapN, its selinux context is:
system_u:object_r:device_t:s0
Shortly, when udev gets notification when new file is created
in /dev, it will then jump in and relabel this file back to the
expected default context:
system_u:object_r:tun_tap_device_t:s0
There is a time gap happened.
Sometimes, it will have migration failed, AVC error message:
type=AVC msg=audit(1349858424.233:42507): avc: denied { read write } for
pid=19926 comm="qemu-kvm" path="/dev/tap33" dev=devtmpfs ino=131524
scontext=unconfined_u:system_r:svirt_t:s0:c598,c908
tcontext=system_u:object_r:device_t:s0 tclass=chr_file
This patch will label the tapfd device before qemu process starts:
system_u:object_r:tun_tap_device_t:MCS(MCS from seclabel->label)
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
Some security drivers require special options to be passed to
the mount system call. Add a security driver API for handling
this data.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To allow the security drivers to apply different configuration
information per hypervisor, pass the virtualization driver name
into the security manager constructor.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When sVirt is integrated with the LXC driver, it will be neccessary
to invoke the security driver APIs using only a virDomainDefPtr
since the lxc_container.c code has no virDomainObjPtr available.
Aside from two functions which want obj->pid, every bit of the
security driver code only touches obj->def. So we don't need to
pass a virDomainObjPtr into the security drivers, a virDomainDefPtr
is sufficient. Two functions also gain a 'pid_t pid' argument.
* src/qemu/qemu_driver.c, src/qemu/qemu_hotplug.c,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c,
src/security/security_dac.c,
src/security/security_driver.h,
src/security/security_manager.c,
src/security/security_manager.h,
src/security/security_nop.c,
src/security/security_selinux.c,
src/security/security_stack.c: Change all security APIs to use a
virDomainDefPtr instead of virDomainObjPtr
The virSecurityManagerSetProcessFDLabel method was introduced
after a mis-understanding from a conversation about SELinux
socket labelling. The virSecurityManagerSetSocketLabel method
should have been used for all such scenarios.
* src/security/security_apparmor.c, src/security/security_apparmor.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: Remove SetProcessFDLabel driver
This API labels all sockets created until ClearSocketLabel is called in
a way that a vm can access them (i.e., they are labeled with svirt_t
based label in SELinux).
The APIs are designed to label a socket in a way that the libvirt daemon
itself is able to access it (i.e., in SELinux the label is virtd_t based
as opposed to svirt_* we use for labeling resources that need to be
accessed by a vm). The new name reflects this.
Add a new security driver method for labelling an FD with
the process label, rather than the image label
* src/libvirt_private.syms, src/security/security_apparmor.c,
src/security/security_dac.c, src/security/security_driver.h,
src/security/security_manager.c, src/security/security_manager.h,
src/security/security_selinux.c, src/security/security_stack.c:
Add virSecurityManagerSetProcessFDLabel & impl
The virSecurityManagerSetFDLabel method is used to label
file descriptors associated with disk images. There will
shortly be a need to label other file descriptors in a
different way. So the current name is ambiguous. Rename
the method to virSecurityManagerSetImageFDLabel to clarify
its purpose
* src/libvirt_private.syms,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c, src/security/security_dac.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: s/FDLabel/ImageFDLabel/
A need was found to set the SELinux context label on an open fd (a
pipe, as a matter of fact). This patch adds a function to the security
driver API that will set the label on an open fd to secdef.label. For
all drivers other than the SELinux driver, it's a NOP. For the SElinux
driver, it calls fsetfilecon().
If the return is a failure, it only returns error up to the caller if
1) the desired label is different from the existing label, 2) the
destination fd is of a type that supports setting the selinux context,
and 3) selinux is in enforcing mode. Otherwise it will return
success. This follows the pattern of the existing function
SELinuxSetFilecon().
The current security driver usage requires horrible code like
if (driver->securityDriver &&
driver->securityDriver->domainSetSecurityHostdevLabel &&
driver->securityDriver->domainSetSecurityHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
This pair of checks for NULL clutters up the code, making the driver
calls 2 lines longer than they really need to be. The goal of the
patchset is to change the calling convention to simply
if (virSecurityManagerSetHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
The first check for 'driver->securityDriver' being NULL is removed
by introducing a 'no op' security driver that will always be present
if no real driver is enabled. This guarentees driver->securityDriver
!= NULL.
The second check for 'driver->securityDriver->domainSetSecurityHostdevLabel'
being non-NULL is hidden in a new abstraction called virSecurityManager.
This separates the driver callbacks, from main internal API. The addition
of a virSecurityManager object, that is separate from the virSecurityDriver
struct also allows for security drivers to carry state / configuration
information directly. Thus the DAC/Stack drivers from src/qemu which
used to pull config from 'struct qemud_driver' can now be moved into
the 'src/security' directory and store their config directly.
* src/qemu/qemu_conf.h, src/qemu/qemu_driver.c: Update to
use new virSecurityManager APIs
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_dac.h
src/qemu/qemu_security_stacked.c, src/qemu/qemu_security_stacked.h:
Move into src/security directory
* src/security/security_stack.c, src/security/security_stack.h,
src/security/security_dac.c, src/security/security_dac.h: Generic
versions of previous QEMU specific drivers
* src/security/security_apparmor.c, src/security/security_apparmor.h,
src/security/security_driver.c, src/security/security_driver.h,
src/security/security_selinux.c, src/security/security_selinux.h:
Update to take virSecurityManagerPtr object as the first param
in all callbacks
* src/security/security_nop.c, src/security/security_nop.h: Stub
implementation of all security driver APIs.
* src/security/security_manager.h, src/security/security_manager.c:
New internal API for invoking security drivers
* src/libvirt.c: Add missing debug for security APIs
Disk format probing is now disabled by default. A new config
option in /etc/qemu/qemu.conf will re-enable it for existing
deployments where this causes trouble
The implementation of security driver callbacks often needs
to access the security driver object. Currently only a handful
of callbacks include the driver object as a parameter. Later
patches require this is many more places.
* src/qemu/qemu_driver.c: Pass in the security driver object
to all callbacks
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_stacked.c,
src/security/security_apparmor.c, src/security/security_driver.h,
src/security/security_selinux.c: Add a virSecurityDriverPtr
param to all security callbacks
When SELinux is running in MLS mode, libvirtd will have a
different security level to the VMs. For libvirtd to be
able to connect to the monitor console, the client end of
the UNIX domain socket needs a different label. This adds
infrastructure to set the socket label via the security
driver framework
* src/qemu/qemu_driver.c: Call out to socket label APIs in
security driver
* src/qemu/qemu_security_stacked.c: Wire up socket label
drivers
* src/security/security_driver.h: Define security driver
entry points for socket labelling
* src/security/security_selinux.c: Set socket label based on
VM label
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().
