All OSes that we support have libselinux >= 2.5 except for Ubuntu 16.04
where the version is 2.4.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Replace all occurrences of
if (VIR_STRDUP(a, b) < 0)
/* effectively dead code */
with:
a = g_strdup(b);
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Replace:
if (!s && VIR_STRDUP(s, str) < 0)
goto;
with:
if (!s)
s = g_strdup(str);
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Replace all the occurrences of
ignore_value(VIR_STRDUP(a, b));
with
a = g_strdup(b);
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since commit 44e7f029159ed701b4a1739ac711507ee53790ed
util: rewrite auto cleanup macros to use glib's equivalent
VIR_AUTOPTR aliases to g_autoptr. Replace all of its use by the GLib
macro version.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Use G_GNUC_UNUSED from GLib instead of ATTRIBUTE_UNUSED.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This function is in fact returning the name of the virtualization
driver that registered the security manager/driver.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@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>
We mirror the labeling strategy that was used for its top image
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
This will be used for recursing into externalDataStore
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
Rename the existing virSecuritySELinuxRestoreImageLabelInt
to virSecuritySELinuxRestoreImageLabelSingle, and extend the new
ImageLabelInt handle externalDataStore
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
This will simplify future patches and make the logic easier to follow
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
The only caller always passes in a non-null parent
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
All the SetFileCon calls only differ by the label they pass in.
Rework the conditionals to track what label we need, and use a
single SetFileCon call
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1755803
The /dev/tpmN file can be opened only once, as implemented in
drivers/char/tpm/tpm-dev.c:tpm_open() from the kernel's tree. Any
other attempt to open the file fails. And since we're opening the
file ourselves and passing the FD to qemu we will not succeed
opening the file again when locking it for seclabel remembering.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
So far all items on the chown/setfilecon list have the same
.remember value. But this will change shortly. Therefore, don't
try to lock paths which we won't manipulate XATTRs for.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
I guess the reason for that was the automatic interpretation/stringification of
setfilecon_errno, but the code was not nice to read and it was a bit confusing.
Also, the logs and error states get cleaner this way.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
There are some network file systems that do support XATTRs (e.g.
gluster via FUSE). And they appear to support SELinux too.
However, not really. Problem is, that it is impossible to change
SELinux label of a file stored there, and yet we claim success
(rightfully - hypervisor succeeds in opening the file). But this
creates a problem for us - from XATTR bookkeeping POV, we haven't
changed the label and thus if we remembered any label, we must
roll back and remove it.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1740506
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
This function is no longer needed because after previous commits
it's just an alias to virSecuritySELinuxSetFilecon.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Now, that we don't need to remember if setting context is
'optional' (the argument only made
virSecuritySELinuxSetFileconImpl() return a different success
code), we can drop it from the _virSecuritySELinuxContextItem
structure as we don't need to remember it in transactions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
There is no real difference between
virSecuritySELinuxSetFilecon() and
virSecuritySELinuxSetFileconOptional(). Drop the latter in favour
of the former.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The only thing that the @optional argument does is that it makes
the function return 1 instead of 0 if setting SELinux context
failed in a non-critical fashion. Drop the argument then and
return 1 in that case. This enables caller to learn if SELinux
context was set or not.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
If user has two domains, each have the same disk (configured for
RW) but each runs with different seclabel then we deny start of
the second domain because in order to do that we would need to
relabel the disk but that would cut the first domain off. Even if
we did not do that, qemu would fail to start because it would be
unable to lock the disk image for the second time. So far, this
behaviour is expected. But what is not expected is that we
increase the refcounter in XATTRs and leave it like that.
What happens is that when the second domain starts,
virSecuritySetRememberedLabel() is called, and since there are
XATTRs from the first domain it increments the refcounter and
returns it (refcounter == 2 at this point). Then callers
(virSecurityDACSetOwnership() and
virSecuritySELinuxSetFileconHelper()) realize that refcounter is
greater than 1 and desired seclabel doesn't match the one the
disk image already has and an error is produced. But the
refcounter is never decremented.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1740024
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
This effectively reverts d7420430ce6 and adds new code.
Here is the problem: Imagine a file X that is to be shared
between two domains as a disk. Let the first domain (vm1) have
seclabel remembering turned on and the other (vm2) has it turned
off. Assume that both domains will run under the same user, but
the original owner of X is different (i.e. trying to access X
without relabelling leads to EPERM).
Let's start vm1 first. This will cause X to be relabelled and to
gain new attributes:
trusted.libvirt.security.ref_dac="1"
trusted.libvirt.security.dac="$originalOwner"
When vm2 is started, X will again be relabelled, but since the
new label is the same as X already has (because of vm1) nothing
changes and vm1 and vm2 can access X just fine. Note that no
XATTR is changed (especially the refcounter keeps its value of 1)
because the vm2 domain has the feature turned off.
Now, vm1 is shut off and vm2 continues running. In seclabel
restore process we would get to X and since its refcounter is 1
we would restore the $originalOwner on it. But this is unsafe to
do because vm2 is still using X (remember the assumption that
$originalOwner and vm2's seclabel are distinct?).
The problem is that refcounter stored in XATTRs doesn't reflect
the actual times a resource is in use. Since I don't see any easy
way around it let's just not store original owner on shared
resources. Shared resource in world of domain disks is:
- whole backing chain but the top layer,
- read only disk (we don't require CDROM to be explicitly
marked as shareable),
- disk marked as shareable.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Just like previous commit allowed to enable or disable owner
remembering for each individual path, do the same for SELinux
driver. This is going to be needed in the next commit.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Both DAC and SELinux drivers support transactions. Each item on
the transaction list consists of various variables and @restore
is one of them. Document it so that as the list of variables grow
it's easier to spot which variable does what.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The way that virSecurityDACRecallLabel is currently written is
that if XATTRs are not supported for given path to the caller
this is not different than if the path is still in use. The value
of 1 is returned which makes secdrivers skip label restore.
This is clearly a bug as we are not restoring labels on say NFS
even though previously we were.
Strictly speaking, changes to virSecurityDACRememberLabel are not
needed, but they are done anyway so that getter and setter behave
in the same fashion.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Just like it's DAC counterpart is doing,
virSecuritySELinuxRestoreAllLabel() could print @migrated in the
debug message.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The d_type field cannot be assumed to be filled. Some filesystems, such
as older XFS, will simply report DT_UNKNOWN.
Even if the d_type is filled in, the use of it in the SELinux functions
is dubious. If labelling all files in a directory there's no reason to
skip things which are not regular files. We merely need to skip "." and
"..", which is done by virDirRead() already.
Signed-off-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>
The @con type security_context_t is actually a "char *", so the
correct check should be to dereference one more level; otherwise,
we could return/use the NULL pointer later in a subsequent
virSecuritySELinuxSetFileconImpl call (using @fcon).
Suggested-by: Michal Prívozník <mprivozn@redhat.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
If virSecuritySELinuxRestoreFileLabel returns 0 or -1 too soon, then
the @newpath will be leaked.
Suggested-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We are setting label on kernel, initrd, dtb and slic_table files.
But we never restored it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It helps whe trying to match calls with virSecuritySELinuxSetAllLabel
if the order in which devices are set/restored is the same in
both functions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When iterating over list of paths/disk sources to relabel it may
happen that the process fails at some point. In that case, for
the sake of keeping seclabel refcount (stored in XATTRs) in sync
with reality we have to perform rollback. However, if that fails
too the only thing we can do is warn user.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It's important to keep XATTRs untouched (well, in the same state
they were in when entering the function). Otherwise our
refcounting would be messed up.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Similarly to what I did in DAC driver, this also requires the
same SELinux label to be used for shared paths. If a path is
already in use by a domain (or domains) then and the domain we
are starting now wants to access the path it has to have the same
SELinux label. This might look too restrictive as the new label
can still guarantee access to already running domains but in
reality it is very unlikely and usually an admin mistake.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It is going to be important to know if the current transaction we
are running is a restore operation or set label operation so that
we know whether to call virSecurityGetRememberedLabel() or
virSecuritySetRememberedLabel(). That is, whether we are in a
restore and therefore have to fetch the remembered label, or we
are in set operation and therefore have to store the original
label.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Ján Tomko <jtomko@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>
Trying to use virlockd to lock metadata turns out to be too big
gun. Since we will always spawn a separate process for relabeling
we are safe to use thread unsafe POSIX locks and take out
virtlockd completely out of the picture.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@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>
Return -1 and report an error message if no transaction is set and
virSecuritySELinuxTransactionCommit is called.
The function description of virSecuritySELinuxTransactionCommit says:
"Also it is considered as error if there's no transaction set and this
function is called."
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
In 4674fc6afd6 I've implemented transactions for selinux driver.
Well, now that I am working in this area I've noticed a subtle
bug: @ret is initialized to 0 instead of -1. Facepalm.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc Hartmayer <mhartmay@linux.ibm.com>
This shouldn't be needed per-se. Security manager shouldn't
disappear during transactions - it's immutable. However, it
doesn't hurt to grab a reference either - transaction code uses
it after all.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This array is allocated in virSecuritySELinuxContextListAppend()
but never freed. This commit is essentially the same as ca25026.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Lock all the paths we want to relabel to mutually exclude other
libvirt daemons.
The only hitch here is that directories can't be locked.
Therefore, when relabeling a directory do not lock it (this
happens only when setting up some domain private paths anyway,
e.g. huge pages directory).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
