libvirt/src/qemu/qemu_security.c
Michal Privoznik 28fdfd20f2 qemu: Label restore path outside of secdriver transactions
As explained in the previous commit, we need to relabel the file
we are restoring the domain from. That is the FD that is passed
to QEMU. If the file is not under /dev then the file inside the
namespace is the very same as the one in the host. And regardless
of using transactions, the file will be relabeled. But, if the
file is under /dev then when using transactions only the copy
inside the namespace is relabeled and the one in the host is not.
But QEMU is reading from the one in the host, actually.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1772838

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2020-04-17 16:24:30 +02:00

722 lines
22 KiB
C

/*
* qemu_security.c: QEMU security management
*
* Copyright (C) 2016 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "qemu_domain.h"
#include "qemu_security.h"
#include "virlog.h"
#define VIR_FROM_THIS VIR_FROM_QEMU
VIR_LOG_INIT("qemu.qemu_process");
int
qemuSecuritySetAllLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
const char *stdin_path,
bool migrated)
{
int ret = -1;
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
/* Explicitly run this outside of transaction. We really want to relabel
* the file in the host and not in the domain's namespace. */
if (virSecurityManagerDomainSetPathLabelRO(driver->securityManager,
vm->def,
stdin_path) < 0)
goto cleanup;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetAllLabel(driver->securityManager,
vm->def,
stdin_path,
priv->chardevStdioLogd,
migrated) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
void
qemuSecurityRestoreAllLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
bool migrated)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
bool transactionStarted = false;
/* In contrast to qemuSecuritySetAllLabel, do not use vm->pid
* here. This function is called from qemuProcessStop() which
* is meant to do cleanup after qemu process died. The
* domain's namespace is gone as qemu was the only process
* running there. We would not succeed in entering the
* namespace then. */
if (virSecurityManagerTransactionStart(driver->securityManager) >= 0)
transactionStarted = true;
virSecurityManagerRestoreAllLabel(driver->securityManager,
vm->def,
migrated,
priv->chardevStdioLogd);
if (transactionStarted &&
virSecurityManagerTransactionCommit(driver->securityManager,
-1, priv->rememberOwner) < 0)
VIR_WARN("Unable to run security manager transaction");
virSecurityManagerTransactionAbort(driver->securityManager);
}
int
qemuSecuritySetImageLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virStorageSourcePtr src,
bool backingChain,
bool chainTop)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
virSecurityDomainImageLabelFlags labelFlags = 0;
if (backingChain)
labelFlags |= VIR_SECURITY_DOMAIN_IMAGE_LABEL_BACKING_CHAIN;
if (chainTop)
labelFlags |= VIR_SECURITY_DOMAIN_IMAGE_PARENT_CHAIN_TOP;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetImageLabel(driver->securityManager,
vm->def, src, labelFlags) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreImageLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virStorageSourcePtr src,
bool backingChain)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
virSecurityDomainImageLabelFlags labelFlags = 0;
if (backingChain)
labelFlags |= VIR_SECURITY_DOMAIN_IMAGE_LABEL_BACKING_CHAIN;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreImageLabel(driver->securityManager,
vm->def, src, labelFlags) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityMoveImageMetadata(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virStorageSourcePtr src,
virStorageSourcePtr dst)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
if (!priv->rememberOwner)
return 0;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
return virSecurityManagerMoveImageMetadata(driver->securityManager, pid, src, dst);
}
int
qemuSecuritySetHostdevLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainHostdevDefPtr hostdev)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetHostdevLabel(driver->securityManager,
vm->def,
hostdev,
NULL) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreHostdevLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainHostdevDefPtr hostdev)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreHostdevLabel(driver->securityManager,
vm->def,
hostdev,
NULL) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecuritySetMemoryLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMemoryDefPtr mem)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetMemoryLabel(driver->securityManager,
vm->def,
mem) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreMemoryLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMemoryDefPtr mem)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreMemoryLabel(driver->securityManager,
vm->def,
mem) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecuritySetInputLabel(virDomainObjPtr vm,
virDomainInputDefPtr input)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetInputLabel(driver->securityManager,
vm->def,
input) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreInputLabel(virDomainObjPtr vm,
virDomainInputDefPtr input)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreInputLabel(driver->securityManager,
vm->def,
input) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecuritySetChardevLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainChrDefPtr chr)
{
int ret = -1;
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetChardevLabel(driver->securityManager,
vm->def,
chr->source,
priv->chardevStdioLogd) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreChardevLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainChrDefPtr chr)
{
int ret = -1;
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreChardevLabel(driver->securityManager,
vm->def,
chr->source,
priv->chardevStdioLogd) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
/*
* qemuSecurityStartVhostUserGPU:
*
* @driver: the QEMU driver
* @vm: the domain object
* @cmd: the command to run
* @existstatus: pointer to int returning exit status of process
* @cmdret: pointer to int returning result of virCommandRun
*
* Start the vhost-user-gpu process with approriate labels.
* This function returns -1 on security setup error, 0 if all the
* setup was done properly. In case the virCommand failed to run
* 0 is returned but cmdret is set appropriately with the process
* exitstatus also set.
*/
int
qemuSecurityStartVhostUserGPU(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virCommandPtr cmd,
int *exitstatus,
int *cmdret)
{
if (virSecurityManagerSetChildProcessLabel(driver->securityManager,
vm->def, cmd) < 0)
return -1;
if (virSecurityManagerPreFork(driver->securityManager) < 0)
return -1;
*cmdret = virCommandRun(cmd, exitstatus);
virSecurityManagerPostFork(driver->securityManager);
if (*cmdret < 0)
return -1;
return 0;
}
/*
* qemuSecurityStartTPMEmulator:
*
* @driver: the QEMU driver
* @vm: the domain object
* @cmd: the command to run
* @uid: the uid to run the emulator
* @gid: the gid to run the emulator
* @existstatus: pointer to int returning exit status of process
* @cmdret: pointer to int returning result of virCommandRun
*
* Start the TPM emulator with appropriate labels. Apply security
* labels to files first.
* This function returns -1 on security setup error, 0 if all the
* setup was done properly. In case the virCommand failed to run
* 0 is returned but cmdret is set appropriately with the process
* exitstatus also set.
*/
int
qemuSecurityStartTPMEmulator(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virCommandPtr cmd,
uid_t uid,
gid_t gid,
int *exitstatus,
int *cmdret)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
int ret = -1;
bool transactionStarted = false;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
return -1;
transactionStarted = true;
if (virSecurityManagerSetTPMLabels(driver->securityManager,
vm->def) < 0) {
virSecurityManagerTransactionAbort(driver->securityManager);
return -1;
}
if (virSecurityManagerTransactionCommit(driver->securityManager,
-1, priv->rememberOwner) < 0)
goto cleanup_abort;
transactionStarted = false;
if (qemuSecurityCommandRun(driver, vm, cmd, uid, gid, exitstatus, cmdret) < 0)
goto cleanup;
ret = 0;
if (*cmdret < 0)
goto cleanup;
return 0;
cleanup:
if (!transactionStarted &&
virSecurityManagerTransactionStart(driver->securityManager) >= 0)
transactionStarted = true;
virSecurityManagerRestoreTPMLabels(driver->securityManager, vm->def);
if (transactionStarted &&
virSecurityManagerTransactionCommit(driver->securityManager,
-1, priv->rememberOwner) < 0)
VIR_WARN("Unable to run security manager transaction");
cleanup_abort:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
void
qemuSecurityCleanupTPMEmulator(virQEMUDriverPtr driver,
virDomainObjPtr vm)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
bool transactionStarted = false;
if (virSecurityManagerTransactionStart(driver->securityManager) >= 0)
transactionStarted = true;
virSecurityManagerRestoreTPMLabels(driver->securityManager, vm->def);
if (transactionStarted &&
virSecurityManagerTransactionCommit(driver->securityManager,
-1, priv->rememberOwner) < 0)
VIR_WARN("Unable to run security manager transaction");
virSecurityManagerTransactionAbort(driver->securityManager);
}
int
qemuSecurityDomainSetPathLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
const char *path,
bool allowSubtree)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerDomainSetPathLabel(driver->securityManager,
vm->def,
path,
allowSubtree) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecuritySetSavedStateLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
const char *savefile)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerSetSavedStateLabel(driver->securityManager,
vm->def,
savefile) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
int
qemuSecurityRestoreSavedStateLabel(virQEMUDriverPtr driver,
virDomainObjPtr vm,
const char *savefile)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
pid_t pid = -1;
int ret = -1;
if (qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
pid = vm->pid;
if (virSecurityManagerTransactionStart(driver->securityManager) < 0)
goto cleanup;
if (virSecurityManagerRestoreSavedStateLabel(driver->securityManager,
vm->def,
savefile) < 0)
goto cleanup;
if (virSecurityManagerTransactionCommit(driver->securityManager,
pid, priv->rememberOwner) < 0)
goto cleanup;
ret = 0;
cleanup:
virSecurityManagerTransactionAbort(driver->securityManager);
return ret;
}
/**
* qemuSecurityCommandRun:
* @driver: the QEMU driver
* @vm: the domain object
* @cmd: the command to run
* @uid: the uid to force
* @gid: the gid to force
* @existstatus: pointer to int returning exit status of process
* @cmdret: pointer to int returning result of virCommandRun
*
* Run @cmd with seclabels set on it. If @uid and/or @gid are not
* -1 then their value is enforced.
*
* Returns: 0 on success,
* -1 otherwise.
*/
int
qemuSecurityCommandRun(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virCommandPtr cmd,
uid_t uid,
gid_t gid,
int *exitstatus,
int *cmdret)
{
if (virSecurityManagerSetChildProcessLabel(driver->securityManager,
vm->def, cmd) < 0)
return -1;
if (uid != (uid_t) -1)
virCommandSetUID(cmd, uid);
if (gid != (gid_t) -1)
virCommandSetGID(cmd, gid);
if (virSecurityManagerPreFork(driver->securityManager) < 0)
return -1;
*cmdret = virCommandRun(cmd, exitstatus);
virSecurityManagerPostFork(driver->securityManager);
return 0;
}