To not introduce more redundant code, helpers are added for
both "selinux", "dac", and "apparmor" backends.
Signed-off-by: Han Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: Osier Yang <jyang@redhat>
v2.5 - v3:
* Splitted from 8/10 of v2.5
* Don't forget the other backends (DAC, and apparmor)
These all existed before virfile.c was created, and for some reason
weren't moved.
This is mostly straightfoward, although the syntax rule prohibiting
write() had to be changed to have an exception for virfile.c instead
of virutil.c.
This movement pointed out that there is a function called
virBuildPath(), and another almost identical function called
virFileBuildPath(). They really should be a single function, which
I'll take care of as soon as I figure out what the arglist should look
like.
The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
If virPCIDeviceGetVFIOGroupDev() failed,
virSecurity*(Set|Restore)HostdevLabel() would fail to free a
virPCIDevice that had been allocated.
These leaks were all introduced (by me) very recently, in commit
f0bd70a.
This isn't strictly speaking a bugfix, but I realized I'd gotten a bit
too verbose when I chose the names for
VIR_DOMAIN_HOSTDEV_PCI_BACKEND_TYPE_*. This shortens them all a bit.
Legacy kvm style pci device assignment requires changes to the
labelling of several sysfs files for each device, but for vfio device
assignment, the only thing that needs to be relabelled/chowned is the
"group" device for the group that contains the device to be assigned.
There will soon be other items related to pci hostdevs that need to be
in the same part of the hostdevsubsys union as the pci address (which
is currently a single member called "pci". This patch replaces the
single member named pci with a struct named pci that contains a single
member named "addr".
Coverity found the DACGenLabel was checking for mgr == NULL after a
possible dereference; however, in order to get into the function the
virSecurityManagerGenLabel would have already dereferenced sec_managers[i]
so the check was unnecessary. Same check is made in SELinuxGenSecurityLabel.
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>
The libvirt coding standard is to use 'function(...args...)'
instead of 'function (...args...)'. A non-trivial number of
places did not follow this rule and are fixed in this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Fixes a build failure on cygwin:
cc1: warnings being treated as errors
security/security_dac.c: In function 'virSecurityDACSetProcessLabel':
security/security_dac.c:862:5: error: format '%u' expects type 'unsigned int', but argument 7 has type 'uid_t' [-Wformat]
security/security_dac.c:862:5: error: format '%u' expects type 'unsigned int', but argument 8 has type 'gid_t' [-Wformat]
* src/security/security_dac.c (virSecurityDACSetProcessLabel)
(virSecurityDACGenLabel): Use proper casts.
We used to walk the backing file chain at least twice per disk,
once to set up cgroup device whitelisting, and once to set up
security labeling. Rather than walk the chain every iteration,
which possibly includes calls to fork() in order to open root-squashed
NFS files, we can exploit the cache of the previous patch.
* src/conf/domain_conf.h (virDomainDiskDefForeachPath): Alter
signature.
* src/conf/domain_conf.c (virDomainDiskDefForeachPath): Require caller
to supply backing chain via disk, if recursion is desired.
* src/security/security_dac.c
(virSecurityDACSetSecurityImageLabel): Adjust caller.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityImageLabel): Likewise.
* src/security/virt-aa-helper.c (get_files): Likewise.
* src/qemu/qemu_cgroup.c (qemuSetupDiskCgroup)
(qemuTeardownDiskCgroup): Likewise.
(qemuSetupCgroup): Pre-populate chain.
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)
All USB device lookup functions emit an error when they cannot find the
requested device. With this patch, their caller can choose if a missing
device is an error or normal condition.
The functions virGetUserID and virGetGroupID are now able to parse
user/group names and IDs in a similar way to coreutils' chown. So, user
and group parsing in security_dac can be simplified.
The DAC driver is missing parsing of group and user names for DAC labels
and currently just parses uid and gid. This patch extends it to support
names, so the following security label definition is now valid:
<seclabel type='static' model='dac' relabel='yes'>
<label>qemu:qemu</label>
<imagelabel>qemu:qemu</imagelabel>
</seclabel>
When it tries to parse an owner or a group, it first tries to resolve it as
a name, if it fails or it's an invalid user/group name then it tries to
parse it as an UID or GID. A leading '+' can also be used for both owner and
group to force it to be parsed as IDs, so the following example is also
valid:
<seclabel type='static' model='dac' relabel='yes'>
<label>+101:+101</label>
<imagelabel>+101:+101</imagelabel>
</seclabel>
This ensures that UID 101 and GUI 101 will be used instead of an user or
group named "101".
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/
The DAC security driver silently ignored errors when parsing the DAC
label and used default values instead.
With a domain containing the following label definition:
<seclabel type='static' model='dac' relabel='yes'>
<label>sdfklsdjlfjklsdjkl</label>
</seclabel>
the domain would start normaly but the disk images would be still owned
by root and no error was displayed.
This patch changes the behavior if the parsing of the label fails (note
that a not present label is not a failure and in this case the default
label should be used) the error isn't masked but is raised that causes
the domain start to fail with a descriptive error message:
virsh # start tr
error: Failed to start domain tr
error: internal error invalid argument: failed to parse DAC seclabel
'sdfklsdjlfjklsdjkl' for domain 'tr'
I also changed the error code to "invalid argument" from "internal
error" and tweaked the various error messages to contain correct and
useful information.
When starting a machine the DAC security driver tries to set the UID and
GID of the newly spawned process. This worked as desired if the desired
label was set. When the label was missing a logical bug in
virSecurityDACGenLabel() caused that uninitialised values were used as
uid and gid for the new process.
With this patch, default values (from qemu driver configuration)
are used if the label is not found.
The DAC security driver uses the virStrToLong_ui function to
parse the uid/gid out of the seclabel string. This works on
Linux where 'uid_t' is an unsigned int, but on Mingw32 it is
just an 'int'. This causes compiler warnings about signed/
unsigned int pointer mis-match.
To avoid this, use explicit 'unsigned int ouruid' local
vars to pass into virStrToLong_ui, and then simply assign
to the 'uid_t' type after parsing
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
These changes make the security drivers able to find and handle the
correct security label information when more than one label is
available. They also update the DAC driver to be used as an usual
security driver.
Signed-off-by: Marcelo Cerri <mhcerri@linux.vnet.ibm.com>
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>
No thanks to 64-bit windows, with 64-bit pid_t, we have to avoid
constructs like 'int pid'. Our API in libvirt-qemu cannot be
changed without breaking ABI; but then again, libvirt-qemu can
only be used on systems that support UNIX sockets, which rules
out Windows (even if qemu could be compiled there) - so for all
points on the call chain that interact with this API decision,
we require a different variable name to make it clear that we
audited the use for safety.
Adding a syntax-check rule only solves half the battle; anywhere
that uses printf on a pid_t still needs to be converted, but that
will be a separate patch.
* cfg.mk (sc_correct_id_types): New syntax check.
* src/libvirt-qemu.c (virDomainQemuAttach): Document why we didn't
use pid_t for pid, and validate for overflow.
* include/libvirt/libvirt-qemu.h (virDomainQemuAttach): Tweak name
for syntax check.
* src/vmware/vmware_conf.c (vmwareExtractPid): Likewise.
* src/driver.h (virDrvDomainQemuAttach): Likewise.
* tools/virsh.c (cmdQemuAttach): Likewise.
* src/remote/qemu_protocol.x (qemu_domain_attach_args): Likewise.
* src/qemu_protocol-structs (qemu_domain_attach_args): Likewise.
* src/util/cgroup.c (virCgroupPidCode, virCgroupKillInternal):
Likewise.
* src/qemu/qemu_command.c(qemuParseProcFileStrings): Likewise.
(qemuParseCommandLinePid): Use pid_t for pid.
* daemon/libvirtd.c (daemonForkIntoBackground): Likewise.
* src/conf/domain_conf.h (_virDomainObj): Likewise.
* src/probes.d (rpc_socket_new): Likewise.
* src/qemu/qemu_command.h (qemuParseCommandLinePid): Likewise.
* src/qemu/qemu_driver.c (qemudGetProcessInfo, qemuDomainAttach):
Likewise.
* src/qemu/qemu_process.c (qemuProcessAttach): Likewise.
* src/qemu/qemu_process.h (qemuProcessAttach): Likewise.
* src/uml/uml_driver.c (umlGetProcessInfo): Likewise.
* src/util/virnetdev.h (virNetDevSetNamespace): Likewise.
* src/util/virnetdev.c (virNetDevSetNamespace): Likewise.
* tests/testutils.c (virtTestCaptureProgramOutput): Likewise.
* src/conf/storage_conf.h (_virStoragePerms): Use mode_t, uid_t,
and gid_t rather than int.
* src/security/security_dac.c (virSecurityDACSetOwnership): Likewise.
* src/conf/storage_conf.c (virStorageDefParsePerms): Avoid
compiler warning.
This eliminates the warning message reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=624447
It was caused by a failure to open an image file that is not
accessible by root (the uid libvirtd is running as) because it's on a
root-squash NFS share, owned by a different user, with permissions of
660 (or maybe 600).
The solution is to use virFileOpenAs() rather than open(). The
codepath that generates the error is during qemuSetupDiskCGroup(), but
the actual open() is in a lower-level generic function called from
many places (virDomainDiskDefForeachPath), so some other pieces of the
code were touched just to add dummy (or possibly useful) uid and gid
arguments.
Eliminating this warning message has the nice side effect that the
requested operation may even succeed (which in this case isn't
necessary, but shouldn't hurt anything either).
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
Network disks don't have paths to be resolved or files to be checked
for ownership. ee3efc41e6 checked this
for some image label functions, but was partially reverted in a
refactor. This finishes adding the check to each security driver's
set and restore label methods for images.
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
This patch fixes the regression with using named pipes for qemu serial
devices noted in:
https://bugzilla.redhat.com/show_bug.cgi?id=740478
The problem was that, while new code in libvirt looks for a single
bidirectional fifo of the name given in the config, then relabels that
and continues without looking for / relabelling the two unidirectional
fifos named ${name}.in and ${name}.out, qemu looks in the opposite
order. So if the user had naively created all three fifos, libvirt
would relabel the bidirectional fifo to allow qemu access, but qemu
would attempt to use the two unidirectional fifos and fail (because it
didn't have proper permissions/rights).
This patch changes the order that libvirt looks for the fifos to match
what qemu does - first it looks for the dual fifos, then it looks for
the single bidirectional fifo. If it finds the dual unidirectional
fifos first, it labels/chowns them and ignores any possible
bidirectional fifo.
(Note commit d37c6a3a (which first appeared in libvirt-0.9.2) added
the code that checked for a bidirectional fifo. Prior to that commit,
bidirectional fifos for serial devices didn't work because libvirt
always required the ${name}.(in|out) fifos to exist, and qemu would
always prefer those.
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.
