mirror of
https://gitlab.com/libvirt/libvirt.git
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380bc1bec7
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>
2512 lines
72 KiB
C
2512 lines
72 KiB
C
/*
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* Copyright (C) 2008-2016 Red Hat, Inc.
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* Copyright (C) 2008 IBM Corp.
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* Copyright (c) 2015 SUSE LINUX Products GmbH, Nuernberg, Germany.
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*
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* lxc_container.c: Performs container setup tasks
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library. If not, see
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* <http://www.gnu.org/licenses/>.
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*/
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#include <config.h>
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#include <fcntl.h>
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#include <sys/ioctl.h>
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#include <sys/mount.h>
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#include <sys/wait.h>
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#include <sys/stat.h>
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#include <unistd.h>
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#include <mntent.h>
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#include <sys/reboot.h>
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#include <linux/reboot.h>
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/* Yes, we want linux private one, for _syscall2() macro */
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#include <linux/unistd.h>
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/* For MS_MOVE */
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#include <linux/fs.h>
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#if WITH_CAPNG
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# include <cap-ng.h>
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#endif
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#if WITH_BLKID
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# include <blkid.h>
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#endif
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#if WITH_SELINUX
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# include <selinux/selinux.h>
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#endif
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#include "virerror.h"
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#include "virlog.h"
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#include "lxc_container.h"
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#include "viralloc.h"
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#include "virnetdevveth.h"
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#include "viruuid.h"
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#include "virfile.h"
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#include "virusb.h"
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#include "vircommand.h"
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#include "virnetdevip.h"
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#include "virprocess.h"
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#include "virstring.h"
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#define VIR_FROM_THIS VIR_FROM_LXC
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VIR_LOG_INIT("lxc.lxc_container");
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/*
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* GLibc headers are behind the kernel, so we define these
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* constants if they're not present already.
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*/
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#ifndef CLONE_NEWPID
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# define CLONE_NEWPID 0x20000000
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#endif
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#ifndef CLONE_NEWUTS
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# define CLONE_NEWUTS 0x04000000
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#endif
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#ifndef CLONE_NEWUSER
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# define CLONE_NEWUSER 0x10000000
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#endif
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#ifndef CLONE_NEWIPC
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# define CLONE_NEWIPC 0x08000000
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#endif
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#ifndef CLONE_NEWNET
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# define CLONE_NEWNET 0x40000000 /* New network namespace */
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#endif
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/* messages between parent and container */
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typedef char lxc_message_t;
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#define LXC_CONTINUE_MSG 'c'
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typedef struct __lxc_child_argv lxc_child_argv_t;
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struct __lxc_child_argv {
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virDomainDefPtr config;
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virSecurityManagerPtr securityDriver;
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size_t nveths;
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char **veths;
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int monitor;
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size_t npassFDs;
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int *passFDs;
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size_t nttyPaths;
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char **ttyPaths;
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int handshakefd;
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int *nsInheritFDs;
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};
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static int lxcContainerMountFSBlock(virDomainFSDefPtr fs,
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const char *srcprefix,
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const char *sec_mount_options);
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/*
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* reboot(LINUX_REBOOT_CMD_CAD_ON) will return -EINVAL
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* in a child pid namespace if container reboot support exists.
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* Otherwise, it will either succeed or return -EPERM.
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*/
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G_GNUC_NORETURN static int
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lxcContainerRebootChild(void *argv)
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{
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int *cmd = argv;
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int ret;
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ret = reboot(*cmd);
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if (ret == -1 && errno == EINVAL)
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_exit(1);
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_exit(0);
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}
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static
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int lxcContainerHasReboot(void)
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{
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int flags = CLONE_NEWPID|CLONE_NEWNS|CLONE_NEWUTS|
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CLONE_NEWIPC|SIGCHLD;
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int cpid;
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char *childStack;
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char *stack;
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char *buf;
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int cmd, v;
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int status;
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char *tmp;
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int stacksize = getpagesize() * 4;
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if (virFileReadAll("/proc/sys/kernel/ctrl-alt-del", 10, &buf) < 0)
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return -1;
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if ((tmp = strchr(buf, '\n')))
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*tmp = '\0';
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if (virStrToLong_i(buf, NULL, 10, &v) < 0) {
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virReportError(VIR_ERR_INTERNAL_ERROR,
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_("Malformed ctrl-alt-del setting '%s'"), buf);
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VIR_FREE(buf);
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return -1;
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}
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VIR_FREE(buf);
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cmd = v ? LINUX_REBOOT_CMD_CAD_ON : LINUX_REBOOT_CMD_CAD_OFF;
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if (VIR_ALLOC_N(stack, stacksize) < 0)
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return -1;
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childStack = stack + stacksize;
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cpid = clone(lxcContainerRebootChild, childStack, flags, &cmd);
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VIR_FREE(stack);
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if (cpid < 0) {
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virReportSystemError(errno, "%s",
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_("Unable to clone to check reboot support"));
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return -1;
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} else if (virProcessWait(cpid, &status, false) < 0) {
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return -1;
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}
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if (status != 1) {
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VIR_DEBUG("Containerized reboot support is missing "
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"(kernel probably too old < 3.4)");
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return 0;
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}
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VIR_DEBUG("Containerized reboot support is available");
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return 1;
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}
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/**
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* lxcContainerBuildInitCmd:
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* @vmDef: pointer to vm definition structure
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*
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* Build a virCommandPtr for launching the container 'init' process
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*
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* Returns a virCommandPtr
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*/
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static virCommandPtr lxcContainerBuildInitCmd(virDomainDefPtr vmDef,
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char **ttyPaths,
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size_t nttyPaths)
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{
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char uuidstr[VIR_UUID_STRING_BUFLEN];
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virCommandPtr cmd;
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virBuffer buf = VIR_BUFFER_INITIALIZER;
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size_t i;
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/* 'container_ptys' must exclude the PTY associated with
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* the /dev/console device, hence start at 1 not 0
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*/
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for (i = 1; i < nttyPaths; i++) {
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if (!STRPREFIX(ttyPaths[i], "/dev/")) {
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virReportError(VIR_ERR_INTERNAL_ERROR,
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_("Expected a /dev path for '%s'"),
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ttyPaths[i]);
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virBufferFreeAndReset(&buf);
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return NULL;
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}
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virBufferAdd(&buf, ttyPaths[i] + 5, -1);
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virBufferAddChar(&buf, ' ');
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}
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virBufferTrim(&buf, NULL, 1);
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if (virBufferCheckError(&buf) < 0)
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return NULL;
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virUUIDFormat(vmDef->uuid, uuidstr);
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cmd = virCommandNew(vmDef->os.init);
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if (vmDef->os.initargv && vmDef->os.initargv[0])
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virCommandAddArgSet(cmd, (const char **)vmDef->os.initargv);
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virCommandAddEnvString(cmd, "PATH=/bin:/sbin");
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virCommandAddEnvString(cmd, "TERM=linux");
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virCommandAddEnvString(cmd, "container=lxc-libvirt");
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virCommandAddEnvString(cmd, "HOME=/");
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virCommandAddEnvPair(cmd, "container_uuid", uuidstr);
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if (nttyPaths > 1)
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virCommandAddEnvPair(cmd, "container_ttys", virBufferCurrentContent(&buf));
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virCommandAddEnvPair(cmd, "LIBVIRT_LXC_UUID", uuidstr);
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virCommandAddEnvPair(cmd, "LIBVIRT_LXC_NAME", vmDef->name);
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if (vmDef->os.cmdline)
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virCommandAddEnvPair(cmd, "LIBVIRT_LXC_CMDLINE", vmDef->os.cmdline);
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if (vmDef->os.initdir)
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virCommandSetWorkingDirectory(cmd, vmDef->os.initdir);
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for (i = 0; vmDef->os.initenv[i]; i++) {
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virCommandAddEnvPair(cmd, vmDef->os.initenv[i]->name,
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vmDef->os.initenv[i]->value);
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}
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virBufferFreeAndReset(&buf);
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return cmd;
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}
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/**
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* lxcContainerSetupFDs:
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* @control: control FD from parent
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* @ttyfd: FD of tty to set as the container console
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* @npassFDs: number of extra FDs
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* @passFDs: list of extra FDs
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*
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* Setup file descriptors in the container. @ttyfd is set to be
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* the container's stdin, stdout & stderr. Any FDs included in
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* @passFDs, will be dup()'d such that they start from stderr+1
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* with no gaps.
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*
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* Returns 0 on success or -1 in case of error
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*/
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static int lxcContainerSetupFDs(int *ttyfd,
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size_t npassFDs, int *passFDs)
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{
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int rc = -1;
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int open_max;
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int fd;
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int last_fd;
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size_t i;
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size_t j;
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VIR_DEBUG("Logging from the container init will now cease "
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"as the FDs are about to be closed for exec of "
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"the container init process");
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if (dup2(*ttyfd, STDIN_FILENO) < 0) {
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virReportSystemError(errno, "%s",
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_("dup2(stdin) failed"));
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goto cleanup;
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}
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if (dup2(*ttyfd, STDOUT_FILENO) < 0) {
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virReportSystemError(errno, "%s",
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_("dup2(stdout) failed"));
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goto cleanup;
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}
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if (dup2(*ttyfd, STDERR_FILENO) < 0) {
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virReportSystemError(errno, "%s",
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_("dup2(stderr) failed"));
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goto cleanup;
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}
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VIR_FORCE_CLOSE(*ttyfd);
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/* Any FDs in @passFDs need to be moved around so that
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* they are numbered, without gaps, starting from
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* STDERR_FILENO + 1
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*/
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for (i = 0; i < npassFDs; i++) {
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int wantfd;
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wantfd = STDERR_FILENO + i + 1;
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VIR_DEBUG("Pass %d onto %d", passFDs[i], wantfd);
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/* If we already have desired FD number, life
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* is easy. Nothing needs renumbering */
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if (passFDs[i] == wantfd)
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continue;
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/*
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* Lets check to see if any later FDs are occupying
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* our desired FD number. If so, we must move them
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* out of the way
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*/
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for (j = i + 1; j < npassFDs; j++) {
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if (passFDs[j] == wantfd) {
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VIR_DEBUG("Clash %zu", j);
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int newfd = dup(passFDs[j]);
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if (newfd < 0) {
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virReportSystemError(errno,
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_("Cannot move fd %d out of the way"),
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passFDs[j]);
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goto cleanup;
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}
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/* We're intentionally not closing the
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* old value of passFDs[j], because we
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* don't want later iterations of the
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* loop to take it back. dup2() will
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* cause it to be closed shortly anyway
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*/
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VIR_DEBUG("Moved clash onto %d", newfd);
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passFDs[j] = newfd;
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}
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}
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/* Finally we can move into our desired FD number */
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if (dup2(passFDs[i], wantfd) < 0) {
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virReportSystemError(errno,
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_("Cannot duplicate fd %d onto fd %d"),
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passFDs[i], wantfd);
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goto cleanup;
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}
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VIR_FORCE_CLOSE(passFDs[i]);
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}
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last_fd = STDERR_FILENO + npassFDs;
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/* Just in case someone forget to set FD_CLOEXEC, explicitly
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* close all remaining FDs before executing the container */
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open_max = sysconf(_SC_OPEN_MAX);
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if (open_max < 0) {
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virReportSystemError(errno, "%s",
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_("sysconf(_SC_OPEN_MAX) failed"));
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goto cleanup;
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}
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|
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for (fd = last_fd + 1; fd < open_max; fd++) {
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int tmpfd = fd;
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VIR_MASS_CLOSE(tmpfd);
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}
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rc = 0;
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cleanup:
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VIR_DEBUG("rc=%d", rc);
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return rc;
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}
|
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|
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/**
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* lxcContainerSendContinue:
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* @control: control FD to child
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*
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* Sends the continue message via the socket pair stored in the vm
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* structure.
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*
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* Returns 0 on success or -1 in case of error
|
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*/
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int lxcContainerSendContinue(int control)
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{
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int rc = -1;
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lxc_message_t msg = LXC_CONTINUE_MSG;
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int writeCount = 0;
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VIR_DEBUG("Send continue on fd %d", control);
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writeCount = safewrite(control, &msg, sizeof(msg));
|
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if (writeCount != sizeof(msg))
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goto error_out;
|
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rc = 0;
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error_out:
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return rc;
|
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}
|
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|
|
/**
|
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* lxcContainerWaitForContinue:
|
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* @control: Control FD from parent
|
|
*
|
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* This function will wait for the container continue message from the
|
|
* parent process. It will send this message on the socket pair stored in
|
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* the vm structure once it has completed the post clone container setup.
|
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*
|
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* Returns 0 on success or -1 in case of error
|
|
*/
|
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int lxcContainerWaitForContinue(int control)
|
|
{
|
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lxc_message_t msg;
|
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int readLen;
|
|
|
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VIR_DEBUG("Wait continue on fd %d", control);
|
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readLen = saferead(control, &msg, sizeof(msg));
|
|
VIR_DEBUG("Got continue on fd %d %d", control, readLen);
|
|
if (readLen != sizeof(msg)) {
|
|
if (readLen >= 0)
|
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errno = EIO;
|
|
return -1;
|
|
}
|
|
if (msg != LXC_CONTINUE_MSG) {
|
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errno = EINVAL;
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* lxcContainerSetID:
|
|
*
|
|
* This function calls setuid and setgid to create proper
|
|
* cred for tasks running in container.
|
|
*
|
|
* Returns 0 on success or -1 in case of error
|
|
*/
|
|
static int lxcContainerSetID(virDomainDefPtr def)
|
|
{
|
|
/* Only call virSetUIDGID when user namespace is enabled
|
|
* for this container. And user namespace is only enabled
|
|
* when nuidmap&ngidmap is not zero */
|
|
|
|
if (!def->idmap.nuidmap)
|
|
return 0;
|
|
|
|
VIR_DEBUG("Setting UID/GID to 0/0");
|
|
if (virSetUIDGID(0, 0, NULL, 0) < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("setuid or setgid failed"));
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static virDomainNetDefPtr
|
|
lxcContainerGetNetDef(virDomainDefPtr vmDef, const char *devName)
|
|
{
|
|
size_t i;
|
|
virDomainNetDefPtr netDef;
|
|
|
|
for (i = 0; i < vmDef->nnets; i++) {
|
|
netDef = vmDef->nets[i];
|
|
if (STREQ_NULLABLE(netDef->ifname_guest_actual, devName))
|
|
return netDef;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* lxcContainerRenameAndEnableInterfaces:
|
|
* @nveths: number of interfaces
|
|
* @veths: interface names
|
|
*
|
|
* This function will rename the interfaces to ethN
|
|
* with id ascending order from zero and enable the
|
|
* renamed interfaces for this container.
|
|
*
|
|
* Returns 0 on success or nonzero in case of error
|
|
*/
|
|
static int
|
|
lxcContainerRenameAndEnableInterfaces(virDomainDefPtr vmDef,
|
|
size_t nveths,
|
|
char **veths)
|
|
{
|
|
int ret = -1;
|
|
size_t i;
|
|
const char *newname;
|
|
virDomainNetDefPtr netDef;
|
|
bool privNet = vmDef->features[VIR_DOMAIN_FEATURE_PRIVNET] ==
|
|
VIR_TRISTATE_SWITCH_ON;
|
|
|
|
for (i = 0; i < nveths; i++) {
|
|
if (!(netDef = lxcContainerGetNetDef(vmDef, veths[i])))
|
|
goto cleanup;
|
|
|
|
newname = netDef->ifname_guest;
|
|
if (!newname) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
|
|
_("Missing device name for container-side veth"));
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_DEBUG("Renaming %s to %s", veths[i], newname);
|
|
if (virNetDevSetName(veths[i], newname) < 0)
|
|
goto cleanup;
|
|
|
|
/* Only enable this device if there is a reason to do so (either
|
|
* at least one IP was specified, or link state was set to up in
|
|
* the config)
|
|
*/
|
|
if (netDef->guestIP.nips ||
|
|
netDef->linkstate == VIR_DOMAIN_NET_INTERFACE_LINK_STATE_UP) {
|
|
VIR_DEBUG("Enabling %s", newname);
|
|
if (virNetDevSetOnline(newname, true) < 0)
|
|
goto cleanup;
|
|
}
|
|
|
|
/* set IP addresses and routes */
|
|
if (virNetDevIPInfoAddToDev(newname, &netDef->guestIP) < 0)
|
|
goto cleanup;
|
|
}
|
|
|
|
/* enable lo device only if there were other net devices */
|
|
if ((veths || privNet) &&
|
|
virNetDevSetOnline("lo", true) < 0)
|
|
goto cleanup;
|
|
|
|
ret = 0;
|
|
cleanup:
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*_syscall2(int, pivot_root, char *, newroot, const char *, oldroot)*/
|
|
extern int pivot_root(const char * new_root, const char * put_old);
|
|
|
|
#ifndef MS_REC
|
|
# define MS_REC 16384
|
|
#endif
|
|
|
|
#ifndef MNT_DETACH
|
|
# define MNT_DETACH 0x00000002
|
|
#endif
|
|
|
|
#ifndef MS_PRIVATE
|
|
# define MS_PRIVATE (1<<18)
|
|
#endif
|
|
|
|
#ifndef MS_SLAVE
|
|
# define MS_SLAVE (1<<19)
|
|
#endif
|
|
|
|
|
|
static int lxcContainerUnmountSubtree(const char *prefix,
|
|
bool isOldRootFS)
|
|
{
|
|
char **mounts = NULL;
|
|
size_t nmounts = 0;
|
|
size_t i;
|
|
int saveErrno;
|
|
const char *failedUmount = NULL;
|
|
int ret = -1;
|
|
|
|
VIR_DEBUG("Unmount subtree from %s", prefix);
|
|
|
|
if (virFileGetMountReverseSubtree("/proc/mounts", prefix,
|
|
&mounts, &nmounts) < 0)
|
|
goto cleanup;
|
|
for (i = 0; i < nmounts; i++) {
|
|
VIR_DEBUG("Umount %s", mounts[i]);
|
|
if (umount(mounts[i]) < 0) {
|
|
char ebuf[1024];
|
|
failedUmount = mounts[i];
|
|
saveErrno = errno;
|
|
VIR_WARN("Failed to unmount '%s', trying to detach subtree '%s': %s",
|
|
failedUmount, mounts[nmounts-1],
|
|
virStrerror(errno, ebuf, sizeof(ebuf)));
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (failedUmount) {
|
|
/* This detaches the subtree */
|
|
if (umount2(mounts[nmounts-1], MNT_DETACH) < 0) {
|
|
virReportSystemError(saveErrno,
|
|
_("Failed to unmount '%s' and could not detach subtree '%s'"),
|
|
failedUmount, mounts[nmounts-1]);
|
|
goto cleanup;
|
|
}
|
|
/* This unmounts the tmpfs on which the old root filesystem was hosted */
|
|
if (isOldRootFS &&
|
|
umount(mounts[nmounts-1]) < 0) {
|
|
virReportSystemError(saveErrno,
|
|
_("Failed to unmount '%s' and could not unmount old root '%s'"),
|
|
failedUmount, mounts[nmounts-1]);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
virStringListFree(mounts);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int lxcContainerResolveSymlinks(virDomainFSDefPtr fs, bool gentle)
|
|
{
|
|
char *newroot;
|
|
|
|
if (!fs->src || !fs->src->path || fs->symlinksResolved)
|
|
return 0;
|
|
|
|
if (access(fs->src->path, F_OK)) {
|
|
if (gentle) {
|
|
/* Just ignore the error for the while, we'll try again later */
|
|
VIR_DEBUG("Skipped unaccessible '%s'", fs->src->path);
|
|
return 0;
|
|
} else {
|
|
virReportSystemError(errno,
|
|
_("Failed to access '%s'"), fs->src->path);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
VIR_DEBUG("Resolving '%s'", fs->src->path);
|
|
if (virFileResolveAllLinks(fs->src->path, &newroot) < 0) {
|
|
if (gentle) {
|
|
VIR_DEBUG("Skipped non-resolvable '%s'", fs->src->path);
|
|
return 0;
|
|
} else {
|
|
virReportSystemError(errno,
|
|
_("Failed to resolve symlink at %s"),
|
|
fs->src->path);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* Mark it resolved to skip it the next time */
|
|
fs->symlinksResolved = true;
|
|
|
|
VIR_DEBUG("Resolved '%s' to %s", fs->src->path, newroot);
|
|
|
|
VIR_FREE(fs->src->path);
|
|
fs->src->path = newroot;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int lxcContainerPrepareRoot(virDomainDefPtr def,
|
|
virDomainFSDefPtr root,
|
|
const char *sec_mount_options)
|
|
{
|
|
char *dst;
|
|
char *tmp;
|
|
|
|
VIR_DEBUG("Prepare root %d", root->type);
|
|
|
|
if (root->type == VIR_DOMAIN_FS_TYPE_MOUNT)
|
|
return 0;
|
|
|
|
if (root->type == VIR_DOMAIN_FS_TYPE_FILE) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
|
|
_("Unexpected root filesystem without loop device"));
|
|
return -1;
|
|
}
|
|
|
|
if (root->type != VIR_DOMAIN_FS_TYPE_BLOCK) {
|
|
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
|
|
_("Unsupported root filesystem type %s"),
|
|
virDomainFSTypeToString(root->type));
|
|
return -1;
|
|
}
|
|
|
|
if (lxcContainerResolveSymlinks(root, false) < 0)
|
|
return -1;
|
|
|
|
if (virAsprintf(&dst, "%s/%s.root",
|
|
LXC_STATE_DIR, def->name) < 0)
|
|
return -1;
|
|
|
|
tmp = root->dst;
|
|
root->dst = dst;
|
|
|
|
if (lxcContainerMountFSBlock(root, "", sec_mount_options) < 0) {
|
|
root->dst = tmp;
|
|
VIR_FREE(dst);
|
|
return -1;
|
|
}
|
|
|
|
root->dst = tmp;
|
|
root->type = VIR_DOMAIN_FS_TYPE_MOUNT;
|
|
VIR_FREE(root->src->path);
|
|
root->src->path = dst;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int lxcContainerPivotRoot(virDomainFSDefPtr root)
|
|
{
|
|
int ret;
|
|
char *oldroot = NULL, *newroot = NULL;
|
|
|
|
ret = -1;
|
|
|
|
VIR_DEBUG("Pivot via %s", root->src->path);
|
|
|
|
/* root->parent must be private, so make / private. */
|
|
if (mount("", "/", "none", MS_PRIVATE|MS_REC, NULL) < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to make root private"));
|
|
goto err;
|
|
}
|
|
|
|
if (virAsprintf(&oldroot, "%s/.oldroot", root->src->path) < 0)
|
|
goto err;
|
|
|
|
if (virFileMakePath(oldroot) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create %s"),
|
|
oldroot);
|
|
goto err;
|
|
}
|
|
|
|
/* Create a tmpfs root since old and new roots must be
|
|
* on separate filesystems */
|
|
if (mount("tmprootfs", oldroot, "tmpfs", 0, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount empty tmpfs at %s"),
|
|
oldroot);
|
|
goto err;
|
|
}
|
|
|
|
/* Create a directory called 'new' in tmpfs */
|
|
if (virAsprintf(&newroot, "%s/new", oldroot) < 0)
|
|
goto err;
|
|
|
|
if (virFileMakePath(newroot) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create %s"),
|
|
newroot);
|
|
goto err;
|
|
}
|
|
|
|
/* ... and mount our root onto it */
|
|
if (mount(root->src->path, newroot, "none", MS_BIND|MS_REC, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to bind %s to new root %s"),
|
|
root->src->path, newroot);
|
|
goto err;
|
|
}
|
|
|
|
if (root->readonly) {
|
|
if (mount(root->src->path, newroot, "none", MS_BIND|MS_REC|MS_RDONLY|MS_REMOUNT, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to make new root %s readonly"),
|
|
root->src->path);
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
/* Now we chdir into the tmpfs, then pivot into the
|
|
* root->src bind-mounted onto '/new' */
|
|
if (chdir(newroot) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to chdir into %s"), newroot);
|
|
goto err;
|
|
}
|
|
|
|
/* The old root directory will live at /.oldroot after
|
|
* this and will soon be unmounted completely */
|
|
if (pivot_root(".", ".oldroot") < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to pivot root"));
|
|
goto err;
|
|
}
|
|
|
|
/* CWD is undefined after pivot_root, so go to / */
|
|
if (chdir("/") < 0)
|
|
goto err;
|
|
|
|
ret = 0;
|
|
|
|
err:
|
|
VIR_FREE(oldroot);
|
|
VIR_FREE(newroot);
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
typedef struct {
|
|
const char *src;
|
|
const char *dst;
|
|
const char *type;
|
|
int mflags;
|
|
bool skipUserNS;
|
|
bool skipUnmounted;
|
|
bool skipNoNetns;
|
|
} virLXCBasicMountInfo;
|
|
|
|
static const virLXCBasicMountInfo lxcBasicMounts[] = {
|
|
{ "proc", "/proc", "proc", MS_NOSUID|MS_NOEXEC|MS_NODEV, false, false, false },
|
|
{ "/proc/sys", "/proc/sys", "none", MS_BIND|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, false, false, false },
|
|
{ "/.oldroot/proc/sys/net/ipv4", "/proc/sys/net/ipv4", "none", MS_BIND, false, false, true },
|
|
{ "/.oldroot/proc/sys/net/ipv6", "/proc/sys/net/ipv6", "none", MS_BIND, false, false, true },
|
|
{ "sysfs", "/sys", "sysfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, false, false, false },
|
|
{ "securityfs", "/sys/kernel/security", "securityfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, true, true, false },
|
|
#if WITH_SELINUX
|
|
{ SELINUX_MOUNT, SELINUX_MOUNT, "selinuxfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, true, true, false },
|
|
#endif
|
|
};
|
|
|
|
|
|
bool lxcIsBasicMountLocation(const char *path)
|
|
{
|
|
size_t i;
|
|
|
|
for (i = 0; i < G_N_ELEMENTS(lxcBasicMounts); i++) {
|
|
if (STREQ(path, lxcBasicMounts[i].dst))
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
static int lxcContainerSetReadOnly(void)
|
|
{
|
|
FILE *procmnt;
|
|
struct mntent mntent;
|
|
char mntbuf[1024];
|
|
int ret = -1;
|
|
char **mounts = NULL;
|
|
size_t nmounts = 0;
|
|
size_t i;
|
|
|
|
if (!(procmnt = setmntent("/proc/mounts", "r"))) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to read /proc/mounts"));
|
|
return -1;
|
|
}
|
|
|
|
while (getmntent_r(procmnt, &mntent, mntbuf, sizeof(mntbuf)) != NULL) {
|
|
char *tmp;
|
|
if (STREQ(mntent.mnt_dir, "/") ||
|
|
STREQ(mntent.mnt_dir, "/.oldroot") ||
|
|
STRPREFIX(mntent.mnt_dir, "/.oldroot/") ||
|
|
lxcIsBasicMountLocation(mntent.mnt_dir))
|
|
continue;
|
|
|
|
tmp = g_strdup(mntent.mnt_dir);
|
|
|
|
if (VIR_APPEND_ELEMENT(mounts, nmounts, tmp) < 0) {
|
|
VIR_FREE(tmp);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
if (!mounts) {
|
|
ret = 0;
|
|
goto cleanup;
|
|
}
|
|
|
|
qsort(mounts, nmounts, sizeof(mounts[0]),
|
|
virStringSortRevCompare);
|
|
|
|
for (i = 0; i < nmounts; i++) {
|
|
VIR_DEBUG("Bind readonly %s", mounts[i]);
|
|
if (mount(mounts[i], mounts[i], "none", MS_BIND|MS_REC|MS_RDONLY|MS_REMOUNT, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to make mount %s readonly"),
|
|
mounts[i]);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
cleanup:
|
|
virStringListFreeCount(mounts, nmounts);
|
|
endmntent(procmnt);
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
static int lxcContainerMountBasicFS(bool userns_enabled,
|
|
bool netns_disabled)
|
|
{
|
|
size_t i;
|
|
int rc = -1;
|
|
char* mnt_src = NULL;
|
|
int mnt_mflags;
|
|
|
|
VIR_DEBUG("Mounting basic filesystems");
|
|
|
|
for (i = 0; i < G_N_ELEMENTS(lxcBasicMounts); i++) {
|
|
bool bindOverReadonly;
|
|
virLXCBasicMountInfo const *mnt = &lxcBasicMounts[i];
|
|
|
|
/* When enable userns but disable netns, kernel will
|
|
* forbid us doing a new fresh mount for sysfs.
|
|
* So we had to do a bind mount for sysfs instead.
|
|
*/
|
|
if (userns_enabled && netns_disabled &&
|
|
STREQ(mnt->src, "sysfs")) {
|
|
mnt_src = g_strdup("/sys");
|
|
mnt_mflags = MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY|MS_BIND;
|
|
} else {
|
|
mnt_src = g_strdup(mnt->src);
|
|
mnt_mflags = mnt->mflags;
|
|
}
|
|
|
|
VIR_DEBUG("Processing %s -> %s",
|
|
mnt_src, mnt->dst);
|
|
|
|
if (mnt->skipUnmounted) {
|
|
char *hostdir;
|
|
int ret;
|
|
|
|
if (virAsprintf(&hostdir, "/.oldroot%s", mnt->dst) < 0)
|
|
goto cleanup;
|
|
|
|
ret = virFileIsMountPoint(hostdir);
|
|
VIR_FREE(hostdir);
|
|
if (ret < 0)
|
|
goto cleanup;
|
|
|
|
if (ret == 0) {
|
|
VIR_DEBUG("Skipping '%s' which isn't mounted in host",
|
|
mnt->dst);
|
|
VIR_FREE(mnt_src);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (mnt->skipUserNS && userns_enabled) {
|
|
VIR_DEBUG("Skipping due to user ns enablement");
|
|
VIR_FREE(mnt_src);
|
|
continue;
|
|
}
|
|
|
|
/* Skip mounts with missing source without shouting: it may be a
|
|
* missing folder in /proc due to the absence of a kernel feature */
|
|
if (STRPREFIX(mnt_src, "/") && !virFileExists(mnt_src)) {
|
|
VIR_DEBUG("Skipping due to missing source: %s", mnt_src);
|
|
VIR_FREE(mnt_src);
|
|
continue;
|
|
}
|
|
|
|
if (mnt->skipNoNetns && netns_disabled) {
|
|
VIR_DEBUG("Skipping due to absence of network namespace");
|
|
VIR_FREE(mnt_src);
|
|
continue;
|
|
}
|
|
|
|
if (virFileMakePath(mnt->dst) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mkdir %s"),
|
|
mnt->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
/*
|
|
* We can't immediately set the MS_RDONLY flag when mounting filesystems
|
|
* because (in at least some kernel versions) this will propagate back
|
|
* to the original mount in the host OS, turning it readonly too. Thus
|
|
* we mount the filesystem in read-write mode initially, and then do a
|
|
* separate read-only bind mount on top of that.
|
|
*/
|
|
bindOverReadonly = !!(mnt_mflags & MS_RDONLY);
|
|
|
|
VIR_DEBUG("Mount %s on %s type=%s flags=0x%x",
|
|
mnt_src, mnt->dst, mnt->type, mnt_mflags & ~MS_RDONLY);
|
|
if (mount(mnt_src, mnt->dst, mnt->type, mnt_mflags & ~MS_RDONLY, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount %s on %s type %s flags=0x%x"),
|
|
mnt_src, mnt->dst, NULLSTR(mnt->type),
|
|
mnt_mflags & ~MS_RDONLY);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (bindOverReadonly &&
|
|
mount(mnt_src, mnt->dst, "none",
|
|
MS_BIND|MS_REMOUNT|mnt_mflags|MS_RDONLY, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to re-mount %s on %s flags=0x%x"),
|
|
mnt_src, mnt->dst,
|
|
MS_BIND|MS_REMOUNT|MS_RDONLY);
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_FREE(mnt_src);
|
|
}
|
|
|
|
rc = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(mnt_src);
|
|
VIR_DEBUG("rc=%d", rc);
|
|
return rc;
|
|
}
|
|
|
|
#if WITH_FUSE
|
|
static int lxcContainerMountProcFuse(virDomainDefPtr def,
|
|
const char *stateDir)
|
|
{
|
|
int ret;
|
|
char *meminfo_path = NULL;
|
|
|
|
VIR_DEBUG("Mount /proc/meminfo stateDir=%s", stateDir);
|
|
|
|
if ((ret = virAsprintf(&meminfo_path,
|
|
"/.oldroot/%s/%s.fuse/meminfo",
|
|
stateDir,
|
|
def->name)) < 0)
|
|
return ret;
|
|
|
|
if ((ret = mount(meminfo_path, "/proc/meminfo",
|
|
NULL, MS_BIND, NULL)) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount %s on /proc/meminfo"),
|
|
meminfo_path);
|
|
}
|
|
|
|
VIR_FREE(meminfo_path);
|
|
return ret;
|
|
}
|
|
#else
|
|
static int lxcContainerMountProcFuse(virDomainDefPtr def G_GNUC_UNUSED,
|
|
const char *stateDir G_GNUC_UNUSED)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static int lxcContainerMountFSDev(virDomainDefPtr def,
|
|
const char *stateDir)
|
|
{
|
|
int ret = -1;
|
|
char *path = NULL;
|
|
int flags = def->idmap.nuidmap ? MS_BIND : MS_MOVE;
|
|
|
|
VIR_DEBUG("Mount /dev/ stateDir=%s", stateDir);
|
|
|
|
if ((ret = virAsprintf(&path, "/.oldroot/%s/%s.dev",
|
|
stateDir, def->name)) < 0)
|
|
return ret;
|
|
|
|
if (virFileMakePath("/dev") < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Cannot create /dev"));
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_DEBUG("Trying to %s %s to /dev", def->idmap.nuidmap ?
|
|
"bind" : "move", path);
|
|
|
|
if (mount(path, "/dev", "none", flags, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount %s on /dev"),
|
|
path);
|
|
goto cleanup;
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(path);
|
|
return ret;
|
|
}
|
|
|
|
static int lxcContainerMountFSDevPTS(virDomainDefPtr def,
|
|
const char *stateDir)
|
|
{
|
|
int ret = -1;
|
|
char *path = NULL;
|
|
int flags = def->idmap.nuidmap ? MS_BIND : MS_MOVE;
|
|
|
|
VIR_DEBUG("Mount /dev/pts stateDir=%s", stateDir);
|
|
|
|
if (virAsprintf(&path, "/.oldroot/%s/%s.devpts",
|
|
stateDir, def->name) < 0)
|
|
return ret;
|
|
|
|
if (virFileMakePath("/dev/pts") < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Cannot create /dev/pts"));
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_DEBUG("Trying to %s %s to /dev/pts", def->idmap.nuidmap ?
|
|
"bind" : "move", path);
|
|
|
|
if (mount(path, "/dev/pts", "none", flags, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount %s on /dev/pts"),
|
|
path);
|
|
goto cleanup;
|
|
}
|
|
|
|
ret = 0;
|
|
cleanup:
|
|
VIR_FREE(path);
|
|
return ret;
|
|
}
|
|
|
|
static int lxcContainerSetupDevices(char **ttyPaths, size_t nttyPaths)
|
|
{
|
|
size_t i;
|
|
const struct {
|
|
const char *src;
|
|
const char *dst;
|
|
} links[] = {
|
|
{ "/proc/self/fd/0", "/dev/stdin" },
|
|
{ "/proc/self/fd/1", "/dev/stdout" },
|
|
{ "/proc/self/fd/2", "/dev/stderr" },
|
|
{ "/proc/self/fd", "/dev/fd" },
|
|
};
|
|
|
|
for (i = 0; i < G_N_ELEMENTS(links); i++) {
|
|
if (symlink(links[i].src, links[i].dst) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to symlink device %s to %s"),
|
|
links[i].dst, links[i].src);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* We have private devpts capability, so bind that */
|
|
if (virFileBindMountDevice("/dev/pts/ptmx", "/dev/ptmx") < 0)
|
|
return -1;
|
|
|
|
for (i = 0; i < nttyPaths; i++) {
|
|
char *tty;
|
|
if (virAsprintf(&tty, "/dev/tty%zu", i+1) < 0)
|
|
return -1;
|
|
|
|
if (virFileBindMountDevice(ttyPaths[i], tty) < 0) {
|
|
VIR_FREE(tty);
|
|
return -1;
|
|
}
|
|
|
|
VIR_FREE(tty);
|
|
|
|
if (i == 0 &&
|
|
virFileBindMountDevice(ttyPaths[i], "/dev/console") < 0)
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int lxcContainerMountFSBind(virDomainFSDefPtr fs,
|
|
const char *srcprefix)
|
|
{
|
|
char *src = NULL;
|
|
int ret = -1;
|
|
struct stat st;
|
|
|
|
VIR_DEBUG("src=%s dst=%s", fs->src->path, fs->dst);
|
|
|
|
if (virAsprintf(&src, "%s%s", srcprefix, fs->src->path) < 0)
|
|
goto cleanup;
|
|
|
|
if (stat(fs->dst, &st) < 0) {
|
|
if (errno != ENOENT) {
|
|
virReportSystemError(errno, _("Unable to stat bind target %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
/* ENOENT => create the target dir or file */
|
|
if (stat(src, &st) < 0) {
|
|
virReportSystemError(errno, _("Unable to stat bind source %s"),
|
|
src);
|
|
goto cleanup;
|
|
}
|
|
if (S_ISDIR(st.st_mode)) {
|
|
if (virFileMakePath(fs->dst) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
} else {
|
|
/* Create Empty file for target mount point */
|
|
int fd = open(fs->dst, O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666);
|
|
if (fd < 0) {
|
|
if (errno != EEXIST) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create bind target %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
if (VIR_CLOSE(fd) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to close bind target %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (mount(src, fs->dst, "none", MS_BIND, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to bind mount directory %s to %s"),
|
|
src, fs->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (fs->readonly) {
|
|
VIR_DEBUG("Binding %s readonly", fs->dst);
|
|
if (mount(src, fs->dst, "none", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to make directory %s readonly"),
|
|
fs->dst);
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(src);
|
|
return ret;
|
|
}
|
|
|
|
|
|
#ifdef WITH_BLKID
|
|
static int
|
|
lxcContainerMountDetectFilesystem(const char *src, char **type)
|
|
{
|
|
int fd;
|
|
int ret = -1;
|
|
int rc;
|
|
const char *data = NULL;
|
|
blkid_probe blkid = NULL;
|
|
|
|
*type = NULL;
|
|
|
|
if ((fd = open(src, O_RDONLY)) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Unable to open filesystem %s"), src);
|
|
return -1;
|
|
}
|
|
|
|
if (!(blkid = blkid_new_probe())) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Unable to create blkid library handle"));
|
|
goto cleanup;
|
|
}
|
|
if (blkid_probe_set_device(blkid, fd, 0, 0) < 0) {
|
|
virReportSystemError(EINVAL,
|
|
_("Unable to associate device %s with blkid library"),
|
|
src);
|
|
goto cleanup;
|
|
}
|
|
|
|
blkid_probe_enable_superblocks(blkid, 1);
|
|
|
|
blkid_probe_set_superblocks_flags(blkid, BLKID_SUBLKS_TYPE);
|
|
|
|
rc = blkid_do_safeprobe(blkid);
|
|
if (rc != 0) {
|
|
if (rc == 1) /* Nothing found, return success with *type == NULL */
|
|
goto done;
|
|
|
|
if (rc == -2) {
|
|
virReportSystemError(EINVAL,
|
|
_("Too many filesystems detected for %s"),
|
|
src);
|
|
} else {
|
|
virReportSystemError(errno,
|
|
_("Unable to detect filesystem for %s"),
|
|
src);
|
|
}
|
|
goto cleanup;
|
|
}
|
|
|
|
if (blkid_probe_lookup_value(blkid, "TYPE", &data, NULL) < 0) {
|
|
virReportSystemError(ENOENT,
|
|
_("Unable to find filesystem type for %s"),
|
|
src);
|
|
goto cleanup;
|
|
}
|
|
|
|
*type = g_strdup(data);
|
|
|
|
done:
|
|
ret = 0;
|
|
cleanup:
|
|
VIR_FORCE_CLOSE(fd);
|
|
if (blkid)
|
|
blkid_free_probe(blkid);
|
|
return ret;
|
|
}
|
|
#else /* ! WITH_BLKID */
|
|
static int
|
|
lxcContainerMountDetectFilesystem(const char *src G_GNUC_UNUSED,
|
|
char **type)
|
|
{
|
|
/* No libblkid, so just return success with no detected type */
|
|
*type = NULL;
|
|
return 0;
|
|
}
|
|
#endif /* ! WITH_BLKID */
|
|
|
|
/*
|
|
* This function attempts to do automatic detection of filesystem
|
|
* type following the same rules as the util-linux 'mount' binary.
|
|
*
|
|
* The main difference is that we don't (currently) try to use
|
|
* libblkid to detect the format first. We go straight to using
|
|
* /etc/filesystems, and then /proc/filesystems
|
|
*/
|
|
static int lxcContainerMountFSBlockAuto(virDomainFSDefPtr fs,
|
|
int fsflags,
|
|
const char *src,
|
|
const char *srcprefix,
|
|
const char *sec_mount_options)
|
|
{
|
|
FILE *fp = NULL;
|
|
int ret = -1;
|
|
bool tryProc = false;
|
|
bool gotStar = false;
|
|
char *fslist = NULL;
|
|
char *line = NULL;
|
|
const char *type;
|
|
|
|
VIR_DEBUG("src=%s dst=%s srcprefix=%s", src, fs->dst, srcprefix);
|
|
|
|
/* First time around we use /etc/filesystems */
|
|
retry:
|
|
if (virAsprintf(&fslist, "%s%s", srcprefix,
|
|
tryProc ? "/proc/filesystems" : "/etc/filesystems") < 0)
|
|
goto cleanup;
|
|
|
|
VIR_DEBUG("Open fslist %s", fslist);
|
|
if (!(fp = fopen(fslist, "r"))) {
|
|
/* If /etc/filesystems does not exist, then we need to retry
|
|
* with /proc/filesystems next
|
|
*/
|
|
if (errno == ENOENT &&
|
|
!tryProc) {
|
|
tryProc = true;
|
|
VIR_FREE(fslist);
|
|
goto retry;
|
|
}
|
|
|
|
virReportSystemError(errno,
|
|
_("Unable to read %s"),
|
|
fslist);
|
|
goto cleanup;
|
|
}
|
|
|
|
while (!feof(fp)) {
|
|
size_t n;
|
|
VIR_FREE(line);
|
|
if (getline(&line, &n, fp) <= 0) {
|
|
if (feof(fp))
|
|
break;
|
|
|
|
goto cleanup;
|
|
}
|
|
|
|
if (strstr(line, "nodev"))
|
|
continue;
|
|
|
|
type = strchr(line, '\n');
|
|
if (type)
|
|
line[type-line] = '\0';
|
|
|
|
type = line;
|
|
virSkipSpaces(&type);
|
|
|
|
/*
|
|
* /etc/filesystems is only allowed to contain '*' on the last line
|
|
*/
|
|
if (gotStar && !tryProc) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
_("%s has unexpected '*' before last line"),
|
|
fslist);
|
|
goto cleanup;
|
|
}
|
|
|
|
/* An '*' on the last line in /etc/filesystems
|
|
* means try /proc/filesystems next. We don't
|
|
* jump immediately though, since we need to see
|
|
* if any more lines follow
|
|
*/
|
|
if (!tryProc &&
|
|
STREQ(type, "*"))
|
|
gotStar = true;
|
|
|
|
VIR_DEBUG("Trying mount '%s' on '%s' with '%s' opts '%s'",
|
|
src, fs->dst, type, sec_mount_options);
|
|
if (mount(src, fs->dst, type, fsflags, sec_mount_options) < 0) {
|
|
/* These errnos indicate a bogus filesystem type for
|
|
* the image we have, so skip to the next type
|
|
*/
|
|
if (errno == EINVAL || errno == ENODEV)
|
|
continue;
|
|
|
|
virReportSystemError(errno,
|
|
_("Failed to mount device %s to %s"),
|
|
src, fs->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
/* We've got to the end of /etc/filesystems and saw
|
|
* a '*', so we must try /proc/filesystems next
|
|
*/
|
|
if (ret != 0 &&
|
|
!tryProc &&
|
|
gotStar) {
|
|
tryProc = true;
|
|
VIR_FREE(fslist);
|
|
VIR_FORCE_FCLOSE(fp);
|
|
goto retry;
|
|
}
|
|
|
|
if (ret != 0) {
|
|
virReportSystemError(ENODEV,
|
|
_("Failed to mount device %s to %s, unable to detect filesystem"),
|
|
src, fs->dst);
|
|
}
|
|
|
|
VIR_DEBUG("Done mounting filesystem ret=%d tryProc=%d", ret, tryProc);
|
|
|
|
cleanup:
|
|
VIR_FREE(line);
|
|
VIR_FREE(fslist);
|
|
VIR_FORCE_FCLOSE(fp);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* Mount a block device 'src' on fs->dst, automatically
|
|
* probing for filesystem type
|
|
*/
|
|
static int lxcContainerMountFSBlockHelper(virDomainFSDefPtr fs,
|
|
const char *src,
|
|
const char *srcprefix,
|
|
const char *sec_mount_options)
|
|
{
|
|
int fsflags = 0;
|
|
int ret = -1;
|
|
char *format = NULL;
|
|
|
|
if (fs->readonly)
|
|
fsflags |= MS_RDONLY;
|
|
|
|
if (virFileMakePath(fs->dst) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (lxcContainerMountDetectFilesystem(src, &format) < 0)
|
|
goto cleanup;
|
|
|
|
if (format) {
|
|
VIR_DEBUG("Mount '%s' on '%s' with detected format '%s' opts '%s'",
|
|
src, fs->dst, format, sec_mount_options);
|
|
if (mount(src, fs->dst, format, fsflags, sec_mount_options) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount device %s to %s as %s"),
|
|
src, fs->dst, format);
|
|
goto cleanup;
|
|
}
|
|
ret = 0;
|
|
} else {
|
|
ret = lxcContainerMountFSBlockAuto(fs, fsflags, src, srcprefix, sec_mount_options);
|
|
}
|
|
|
|
cleanup:
|
|
VIR_FREE(format);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int lxcContainerMountFSBlock(virDomainFSDefPtr fs,
|
|
const char *srcprefix,
|
|
const char *sec_mount_options)
|
|
{
|
|
char *src = NULL;
|
|
int ret = -1;
|
|
|
|
VIR_DEBUG("src=%s dst=%s", fs->src->path, fs->dst);
|
|
|
|
if (virAsprintf(&src, "%s%s", srcprefix, fs->src->path) < 0)
|
|
goto cleanup;
|
|
|
|
ret = lxcContainerMountFSBlockHelper(fs, src, srcprefix, sec_mount_options);
|
|
|
|
VIR_DEBUG("Done mounting filesystem ret=%d", ret);
|
|
|
|
cleanup:
|
|
VIR_FREE(src);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int lxcContainerMountFSTmpfs(virDomainFSDefPtr fs,
|
|
char *sec_mount_options)
|
|
{
|
|
int ret = -1;
|
|
char *data = NULL;
|
|
|
|
VIR_DEBUG("usage=%lld sec=%s", fs->usage, sec_mount_options);
|
|
|
|
if (virAsprintf(&data,
|
|
"size=%lld%s", fs->usage, sec_mount_options) < 0)
|
|
goto cleanup;
|
|
|
|
if (virFileMakePath(fs->dst) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create %s"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (mount("tmpfs", fs->dst, "tmpfs", MS_NOSUID|MS_NODEV, data) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to mount directory %s as tmpfs"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (fs->readonly) {
|
|
VIR_DEBUG("Binding %s readonly", fs->dst);
|
|
if (mount(fs->dst, fs->dst, "none", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to make directory %s readonly"),
|
|
fs->dst);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(data);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int lxcContainerMountFS(virDomainFSDefPtr fs,
|
|
char *sec_mount_options)
|
|
{
|
|
switch (fs->type) {
|
|
case VIR_DOMAIN_FS_TYPE_MOUNT:
|
|
if (lxcContainerMountFSBind(fs, "/.oldroot") < 0)
|
|
return -1;
|
|
break;
|
|
case VIR_DOMAIN_FS_TYPE_BLOCK:
|
|
if (lxcContainerMountFSBlock(fs, "/.oldroot", sec_mount_options) < 0)
|
|
return -1;
|
|
break;
|
|
case VIR_DOMAIN_FS_TYPE_RAM:
|
|
if (lxcContainerMountFSTmpfs(fs, sec_mount_options) < 0)
|
|
return -1;
|
|
break;
|
|
case VIR_DOMAIN_FS_TYPE_BIND:
|
|
if (lxcContainerMountFSBind(fs, "") < 0)
|
|
return -1;
|
|
break;
|
|
case VIR_DOMAIN_FS_TYPE_FILE:
|
|
/* We do actually support this, but the lxc controller
|
|
* should have associated the file with a loopback
|
|
* device and changed this to TYPE_BLOCK for us */
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
_("Unexpected filesystem type %s"),
|
|
virDomainFSTypeToString(fs->type));
|
|
return -1;
|
|
default:
|
|
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
|
|
_("Cannot mount filesystem type %s"),
|
|
virDomainFSTypeToString(fs->type));
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int lxcContainerMountAllFS(virDomainDefPtr vmDef,
|
|
char *sec_mount_options)
|
|
{
|
|
size_t i;
|
|
VIR_DEBUG("Mounting all non-root filesystems");
|
|
|
|
/* Pull in rest of container's mounts */
|
|
for (i = 0; i < vmDef->nfss; i++) {
|
|
if (STREQ(vmDef->fss[i]->dst, "/"))
|
|
continue;
|
|
|
|
VIR_DEBUG("Mounting '%s' -> '%s'", vmDef->fss[i]->src->path, vmDef->fss[i]->dst);
|
|
|
|
if (lxcContainerResolveSymlinks(vmDef->fss[i], false) < 0)
|
|
return -1;
|
|
|
|
if (!(vmDef->fss[i]->src && vmDef->fss[i]->src->path &&
|
|
STRPREFIX(vmDef->fss[i]->src->path, vmDef->fss[i]->dst)) &&
|
|
lxcContainerUnmountSubtree(vmDef->fss[i]->dst, false) < 0)
|
|
return -1;
|
|
|
|
if (lxcContainerMountFS(vmDef->fss[i], sec_mount_options) < 0)
|
|
return -1;
|
|
}
|
|
|
|
VIR_DEBUG("Mounted all non-root filesystems");
|
|
return 0;
|
|
}
|
|
|
|
|
|
int lxcContainerSetupHostdevCapsMakePath(const char *dev)
|
|
{
|
|
int ret = -1;
|
|
char *dir, *tmp;
|
|
|
|
dir = g_strdup(dev);
|
|
|
|
if ((tmp = strrchr(dir, '/'))) {
|
|
*tmp = '\0';
|
|
if (virFileMakePath(dir) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to create directory for '%s' dev '%s'"),
|
|
dir, dev);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(dir);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int lxcContainerUnmountForSharedRoot(const char *stateDir,
|
|
const char *domain)
|
|
{
|
|
int ret = -1;
|
|
char *tmp = NULL;
|
|
|
|
#if WITH_SELINUX
|
|
/* Some versions of Linux kernel don't let you overmount
|
|
* the selinux filesystem, so make sure we kill it first
|
|
*/
|
|
/* Filed coverity bug for false positive 'USE_AFTER_FREE' due to swap
|
|
* of root->src with root->dst and the VIR_FREE(root->src) prior to the
|
|
* reset of root->src in lxcContainerPrepareRoot()
|
|
*/
|
|
/* coverity[deref_arg] */
|
|
if (lxcContainerUnmountSubtree(SELINUX_MOUNT, false) < 0)
|
|
goto cleanup;
|
|
#endif
|
|
|
|
/* These filesystems are created by libvirt temporarily, they
|
|
* shouldn't appear in container. */
|
|
if (virAsprintf(&tmp, "%s/%s.dev", stateDir, domain) < 0 ||
|
|
lxcContainerUnmountSubtree(tmp, false) < 0)
|
|
goto cleanup;
|
|
|
|
VIR_FREE(tmp);
|
|
if (virAsprintf(&tmp, "%s/%s.devpts", stateDir, domain) < 0 ||
|
|
lxcContainerUnmountSubtree(tmp, false) < 0)
|
|
goto cleanup;
|
|
|
|
#if WITH_FUSE
|
|
VIR_FREE(tmp);
|
|
if (virAsprintf(&tmp, "%s/%s.fuse", stateDir, domain) < 0 ||
|
|
lxcContainerUnmountSubtree(tmp, false) < 0)
|
|
goto cleanup;
|
|
#endif
|
|
|
|
/* If we have the root source being '/', then we need to
|
|
* get rid of any existing stuff under /proc, /sys & /tmp.
|
|
* We need new namespace aware versions of those. We must
|
|
* do /proc last otherwise we won't find /proc/mounts :-) */
|
|
if (lxcContainerUnmountSubtree("/sys", false) < 0 ||
|
|
lxcContainerUnmountSubtree("/dev", false) < 0 ||
|
|
lxcContainerUnmountSubtree("/proc", false) < 0)
|
|
goto cleanup;
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(tmp);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static bool
|
|
lxcNeedNetworkNamespace(virDomainDefPtr def)
|
|
{
|
|
size_t i;
|
|
if (def->nets != NULL)
|
|
return true;
|
|
if (def->features[VIR_DOMAIN_FEATURE_PRIVNET] == VIR_TRISTATE_SWITCH_ON)
|
|
return true;
|
|
for (i = 0; i < def->nhostdevs; i++) {
|
|
if (def->hostdevs[i]->mode == VIR_DOMAIN_HOSTDEV_MODE_CAPABILITIES &&
|
|
def->hostdevs[i]->source.caps.type == VIR_DOMAIN_HOSTDEV_CAPS_TYPE_NET)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
/* Got a FS mapped to /, we're going the pivot_root
|
|
* approach to do a better-chroot-than-chroot
|
|
* this is based on this thread http://lkml.org/lkml/2008/3/5/29
|
|
*/
|
|
static int lxcContainerSetupPivotRoot(virDomainDefPtr vmDef,
|
|
virDomainFSDefPtr root,
|
|
char **ttyPaths,
|
|
size_t nttyPaths,
|
|
virSecurityManagerPtr securityDriver)
|
|
{
|
|
virCgroupPtr cgroup = NULL;
|
|
int ret = -1;
|
|
char *sec_mount_options;
|
|
char *stateDir = NULL;
|
|
|
|
VIR_DEBUG("Setup pivot root");
|
|
|
|
if (!(sec_mount_options = virSecurityManagerGetMountOptions(securityDriver, vmDef)))
|
|
return -1;
|
|
|
|
/* Before pivoting we need to identify any
|
|
* cgroups controllers that are mounted */
|
|
if (virCgroupNewSelf(&cgroup) < 0)
|
|
goto cleanup;
|
|
|
|
if (virFileResolveAllLinks(LXC_STATE_DIR, &stateDir) < 0)
|
|
goto cleanup;
|
|
|
|
/* Ensure the root filesystem is mounted */
|
|
if (lxcContainerPrepareRoot(vmDef, root, sec_mount_options) < 0)
|
|
goto cleanup;
|
|
|
|
/* Gives us a private root, leaving all parent OS mounts on /.oldroot */
|
|
if (lxcContainerPivotRoot(root) < 0)
|
|
goto cleanup;
|
|
|
|
/* FIXME: we should find a way to unmount these mounts for container
|
|
* even user namespace is enabled. */
|
|
if (STREQ(root->src->path, "/") && (!vmDef->idmap.nuidmap) &&
|
|
lxcContainerUnmountForSharedRoot(stateDir, vmDef->name) < 0)
|
|
goto cleanup;
|
|
|
|
/* Mounts the core /proc, /sys, etc filesystems */
|
|
if (lxcContainerMountBasicFS(vmDef->idmap.nuidmap,
|
|
!lxcNeedNetworkNamespace(vmDef)) < 0)
|
|
goto cleanup;
|
|
|
|
/* Ensure entire root filesystem (except /.oldroot) is readonly */
|
|
if (root->readonly &&
|
|
lxcContainerSetReadOnly() < 0)
|
|
goto cleanup;
|
|
|
|
/* Mounts /proc/meminfo etc sysinfo */
|
|
if (lxcContainerMountProcFuse(vmDef, stateDir) < 0)
|
|
goto cleanup;
|
|
|
|
/* Now we can re-mount the cgroups controllers in the
|
|
* same configuration as before */
|
|
if (virCgroupBindMount(cgroup, "/.oldroot/", sec_mount_options) < 0)
|
|
goto cleanup;
|
|
|
|
/* Mounts /dev */
|
|
if (lxcContainerMountFSDev(vmDef, stateDir) < 0)
|
|
goto cleanup;
|
|
|
|
/* Mounts /dev/pts */
|
|
if (lxcContainerMountFSDevPTS(vmDef, stateDir) < 0)
|
|
goto cleanup;
|
|
|
|
/* Setup device nodes in /dev/ */
|
|
if (lxcContainerSetupDevices(ttyPaths, nttyPaths) < 0)
|
|
goto cleanup;
|
|
|
|
/* Sets up any non-root mounts from guest config */
|
|
if (lxcContainerMountAllFS(vmDef, sec_mount_options) < 0)
|
|
goto cleanup;
|
|
|
|
/* Gets rid of all remaining mounts from host OS, including /.oldroot itself */
|
|
if (lxcContainerUnmountSubtree("/.oldroot", true) < 0)
|
|
goto cleanup;
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(stateDir);
|
|
virCgroupFree(&cgroup);
|
|
VIR_FREE(sec_mount_options);
|
|
return ret;
|
|
}
|
|
|
|
static int lxcContainerResolveAllSymlinks(virDomainDefPtr vmDef)
|
|
{
|
|
size_t i;
|
|
|
|
VIR_DEBUG("Resolving symlinks");
|
|
|
|
for (i = 0; i < vmDef->nfss; i++) {
|
|
virDomainFSDefPtr fs = vmDef->fss[i];
|
|
/* In the first pass, be gentle as some files may
|
|
depend on other filesystems to be mounted */
|
|
if (lxcContainerResolveSymlinks(fs, true) < 0)
|
|
return -1;
|
|
}
|
|
VIR_DEBUG("Resolved all filesystem symlinks");
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This is running as the 'init' process inside the container.
|
|
* It removes some capabilities that could be dangerous to
|
|
* host system, since they are not currently "containerized"
|
|
*/
|
|
#if WITH_CAPNG
|
|
|
|
/* Define capabilities to -1 if those aren't defined in the kernel:
|
|
* this will help us ignore them. */
|
|
# ifndef CAP_AUDIT_CONTROL
|
|
# define CAP_AUDIT_CONTROL -1
|
|
# endif
|
|
# ifndef CAP_AUDIT_WRITE
|
|
# define CAP_AUDIT_WRITE -1
|
|
# endif
|
|
# ifndef CAP_BLOCK_SUSPEND
|
|
# define CAP_BLOCK_SUSPEND -1
|
|
# endif
|
|
# ifndef CAP_CHOWN
|
|
# define CAP_CHOWN -1
|
|
# endif
|
|
# ifndef CAP_DAC_OVERRIDE
|
|
# define CAP_DAC_OVERRIDE -1
|
|
# endif
|
|
# ifndef CAP_DAC_READ_SEARCH
|
|
# define CAP_DAC_READ_SEARCH -1
|
|
# endif
|
|
# ifndef CAP_FOWNER
|
|
# define CAP_FOWNER -1
|
|
# endif
|
|
# ifndef CAP_FSETID
|
|
# define CAP_FSETID -1
|
|
# endif
|
|
# ifndef CAP_IPC_LOCK
|
|
# define CAP_IPC_LOCK -1
|
|
# endif
|
|
# ifndef CAP_IPC_OWNER
|
|
# define CAP_IPC_OWNER -1
|
|
# endif
|
|
# ifndef CAP_KILL
|
|
# define CAP_KILL -1
|
|
# endif
|
|
# ifndef CAP_LEASE
|
|
# define CAP_LEASE -1
|
|
# endif
|
|
# ifndef CAP_LINUX_IMMUTABLE
|
|
# define CAP_LINUX_IMMUTABLE -1
|
|
# endif
|
|
# ifndef CAP_MAC_ADMIN
|
|
# define CAP_MAC_ADMIN -1
|
|
# endif
|
|
# ifndef CAP_MAC_OVERRIDE
|
|
# define CAP_MAC_OVERRIDE -1
|
|
# endif
|
|
# ifndef CAP_MKNOD
|
|
# define CAP_MKNOD -1
|
|
# endif
|
|
# ifndef CAP_NET_ADMIN
|
|
# define CAP_NET_ADMIN -1
|
|
# endif
|
|
# ifndef CAP_NET_BIND_SERVICE
|
|
# define CAP_NET_BIND_SERVICE -1
|
|
# endif
|
|
# ifndef CAP_NET_BROADCAST
|
|
# define CAP_NET_BROADCAST -1
|
|
# endif
|
|
# ifndef CAP_NET_RAW
|
|
# define CAP_NET_RAW -1
|
|
# endif
|
|
# ifndef CAP_SETGID
|
|
# define CAP_SETGID -1
|
|
# endif
|
|
# ifndef CAP_SETFCAP
|
|
# define CAP_SETFCAP -1
|
|
# endif
|
|
# ifndef CAP_SETPCAP
|
|
# define CAP_SETPCAP -1
|
|
# endif
|
|
# ifndef CAP_SETUID
|
|
# define CAP_SETUID -1
|
|
# endif
|
|
# ifndef CAP_SYS_ADMIN
|
|
# define CAP_SYS_ADMIN -1
|
|
# endif
|
|
# ifndef CAP_SYS_BOOT
|
|
# define CAP_SYS_BOOT -1
|
|
# endif
|
|
# ifndef CAP_SYS_CHROOT
|
|
# define CAP_SYS_CHROOT -1
|
|
# endif
|
|
# ifndef CAP_SYS_MODULE
|
|
# define CAP_SYS_MODULE -1
|
|
# endif
|
|
# ifndef CAP_SYS_NICE
|
|
# define CAP_SYS_NICE -1
|
|
# endif
|
|
# ifndef CAP_SYS_PACCT
|
|
# define CAP_SYS_PACCT -1
|
|
# endif
|
|
# ifndef CAP_SYS_PTRACE
|
|
# define CAP_SYS_PTRACE -1
|
|
# endif
|
|
# ifndef CAP_SYS_RAWIO
|
|
# define CAP_SYS_RAWIO -1
|
|
# endif
|
|
# ifndef CAP_SYS_RESOURCE
|
|
# define CAP_SYS_RESOURCE -1
|
|
# endif
|
|
# ifndef CAP_SYS_TIME
|
|
# define CAP_SYS_TIME -1
|
|
# endif
|
|
# ifndef CAP_SYS_TTY_CONFIG
|
|
# define CAP_SYS_TTY_CONFIG -1
|
|
# endif
|
|
# ifndef CAP_SYSLOG
|
|
# define CAP_SYSLOG -1
|
|
# endif
|
|
# ifndef CAP_WAKE_ALARM
|
|
# define CAP_WAKE_ALARM -1
|
|
# endif
|
|
|
|
static int lxcContainerDropCapabilities(virDomainDefPtr def,
|
|
bool keepReboot)
|
|
{
|
|
int ret;
|
|
size_t i;
|
|
int policy = def->features[VIR_DOMAIN_FEATURE_CAPABILITIES];
|
|
|
|
/* Maps virDomainCapsFeature to CAPS_* */
|
|
static int capsMapping[] = {CAP_AUDIT_CONTROL,
|
|
CAP_AUDIT_WRITE,
|
|
CAP_BLOCK_SUSPEND,
|
|
CAP_CHOWN,
|
|
CAP_DAC_OVERRIDE,
|
|
CAP_DAC_READ_SEARCH,
|
|
CAP_FOWNER,
|
|
CAP_FSETID,
|
|
CAP_IPC_LOCK,
|
|
CAP_IPC_OWNER,
|
|
CAP_KILL,
|
|
CAP_LEASE,
|
|
CAP_LINUX_IMMUTABLE,
|
|
CAP_MAC_ADMIN,
|
|
CAP_MAC_OVERRIDE,
|
|
CAP_MKNOD,
|
|
CAP_NET_ADMIN,
|
|
CAP_NET_BIND_SERVICE,
|
|
CAP_NET_BROADCAST,
|
|
CAP_NET_RAW,
|
|
CAP_SETGID,
|
|
CAP_SETFCAP,
|
|
CAP_SETPCAP,
|
|
CAP_SETUID,
|
|
CAP_SYS_ADMIN,
|
|
CAP_SYS_BOOT,
|
|
CAP_SYS_CHROOT,
|
|
CAP_SYS_MODULE,
|
|
CAP_SYS_NICE,
|
|
CAP_SYS_PACCT,
|
|
CAP_SYS_PTRACE,
|
|
CAP_SYS_RAWIO,
|
|
CAP_SYS_RESOURCE,
|
|
CAP_SYS_TIME,
|
|
CAP_SYS_TTY_CONFIG,
|
|
CAP_SYSLOG,
|
|
CAP_WAKE_ALARM};
|
|
|
|
capng_get_caps_process();
|
|
|
|
/* Make sure we drop everything if required by the user */
|
|
if (policy == VIR_DOMAIN_CAPABILITIES_POLICY_DENY)
|
|
capng_clear(CAPNG_SELECT_BOTH);
|
|
|
|
/* Apply all single capabilities changes */
|
|
for (i = 0; i < VIR_DOMAIN_CAPS_FEATURE_LAST; i++) {
|
|
bool toDrop = false;
|
|
int state = def->caps_features[i];
|
|
|
|
if (!cap_valid(capsMapping[i]))
|
|
continue;
|
|
|
|
switch ((virDomainCapabilitiesPolicy) policy) {
|
|
|
|
case VIR_DOMAIN_CAPABILITIES_POLICY_DENY:
|
|
if (state == VIR_TRISTATE_SWITCH_ON &&
|
|
(ret = capng_update(CAPNG_ADD,
|
|
CAPNG_EFFECTIVE | CAPNG_PERMITTED |
|
|
CAPNG_INHERITABLE | CAPNG_BOUNDING_SET,
|
|
capsMapping[i])) < 0) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
_("Failed to add capability %s: %d"),
|
|
virDomainCapsFeatureTypeToString(i), ret);
|
|
return -1;
|
|
}
|
|
break;
|
|
|
|
case VIR_DOMAIN_CAPABILITIES_POLICY_DEFAULT:
|
|
switch (i) {
|
|
case VIR_DOMAIN_CAPS_FEATURE_SYS_BOOT: /* No use of reboot */
|
|
toDrop = !keepReboot && (state != VIR_TRISTATE_SWITCH_ON);
|
|
break;
|
|
case VIR_DOMAIN_CAPS_FEATURE_SYS_MODULE: /* No kernel module loading */
|
|
case VIR_DOMAIN_CAPS_FEATURE_SYS_TIME: /* No changing the clock */
|
|
case VIR_DOMAIN_CAPS_FEATURE_MKNOD: /* No creating device nodes */
|
|
case VIR_DOMAIN_CAPS_FEATURE_AUDIT_CONTROL: /* No messing with auditing status */
|
|
case VIR_DOMAIN_CAPS_FEATURE_MAC_ADMIN: /* No messing with LSM config */
|
|
toDrop = (state != VIR_TRISTATE_SWITCH_ON);
|
|
break;
|
|
default: /* User specified capabilities to drop */
|
|
toDrop = (state == VIR_TRISTATE_SWITCH_OFF);
|
|
}
|
|
G_GNUC_FALLTHROUGH;
|
|
|
|
case VIR_DOMAIN_CAPABILITIES_POLICY_ALLOW:
|
|
if (policy == VIR_DOMAIN_CAPABILITIES_POLICY_ALLOW)
|
|
toDrop = state == VIR_TRISTATE_SWITCH_OFF;
|
|
|
|
if (toDrop && (ret = capng_update(CAPNG_DROP,
|
|
CAPNG_EFFECTIVE | CAPNG_PERMITTED |
|
|
CAPNG_INHERITABLE | CAPNG_BOUNDING_SET,
|
|
capsMapping[i])) < 0) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
_("Failed to remove capability %s: %d"),
|
|
virDomainCapsFeatureTypeToString(i), ret);
|
|
return -1;
|
|
}
|
|
break;
|
|
|
|
case VIR_DOMAIN_CAPABILITIES_POLICY_LAST:
|
|
default:
|
|
virReportEnumRangeError(virDomainCapabilitiesPolicy, policy);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
if ((ret = capng_apply(CAPNG_SELECT_BOTH)) < 0) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
_("Failed to apply capabilities: %d"), ret);
|
|
return -1;
|
|
}
|
|
|
|
/* We do not need to call capng_lock() in this case. The bounding
|
|
* set restriction will prevent them reacquiring sys_boot/module/time,
|
|
* etc which is all that matters for the container. Once inside the
|
|
* container it is fine for SECURE_NOROOT / SECURE_NO_SETUID_FIXUP to
|
|
* be unmasked - they can never escape the bounding set. */
|
|
|
|
return 0;
|
|
}
|
|
#else
|
|
static int lxcContainerDropCapabilities(virDomainDefPtr def G_GNUC_UNUSED,
|
|
bool keepReboot G_GNUC_UNUSED)
|
|
{
|
|
VIR_WARN("libcap-ng support not compiled in, unable to clear capabilities");
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
|
|
/**
|
|
* lxcAttach_ns:
|
|
* @ns_fd: array of namespaces to attach
|
|
*/
|
|
static int lxcAttachNS(int *ns_fd)
|
|
{
|
|
if (ns_fd &&
|
|
virProcessSetNamespaces((size_t)VIR_LXC_DOMAIN_NAMESPACE_LAST,
|
|
ns_fd) < 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* lxcContainerSetUserGroup:
|
|
* @cmd: command to update
|
|
* @vmDef: domain definition for the container
|
|
* @ttyPath: guest path to the tty
|
|
*
|
|
* Set the command UID and GID. As this function attempts at
|
|
* converting the user/group name into uid/gid, it needs to
|
|
* be called after the pivot root is done.
|
|
*
|
|
* The owner of the tty is also changed to the given user.
|
|
*/
|
|
static int lxcContainerSetUserGroup(virCommandPtr cmd,
|
|
virDomainDefPtr vmDef,
|
|
const char *ttyPath)
|
|
{
|
|
uid_t uid;
|
|
gid_t gid;
|
|
|
|
if (vmDef->os.inituser) {
|
|
if (virGetUserID(vmDef->os.inituser, &uid) < 0) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR, _("User %s doesn't exist"),
|
|
vmDef->os.inituser);
|
|
return -1;
|
|
}
|
|
virCommandSetUID(cmd, uid);
|
|
|
|
/* Change the newly created tty owner to the inituid for
|
|
* shells to have job control. */
|
|
if (chown(ttyPath, uid, -1) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to change ownership of tty %s"),
|
|
ttyPath);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
if (vmDef->os.initgroup) {
|
|
if (virGetGroupID(vmDef->os.initgroup, &gid) < 0) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR, _("Group %s doesn't exist"),
|
|
vmDef->os.initgroup);
|
|
return -1;
|
|
}
|
|
virCommandSetGID(cmd, gid);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const char hostname_validchars[] =
|
|
"abcdefghijklmnopqrstuvwxyz"
|
|
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
|
|
"0123456789-";
|
|
|
|
static int lxcContainerSetHostname(virDomainDefPtr def)
|
|
{
|
|
int ret = -1;
|
|
char *name = NULL;
|
|
char *hostname = NULL;
|
|
|
|
/* Filter the VM name to get a valid hostname */
|
|
name = g_strdup(def->name);
|
|
|
|
/* RFC 1123 allows 0-9 digits as a first character in hostname */
|
|
virStringFilterChars(name, hostname_validchars);
|
|
hostname = name;
|
|
if (strlen(name) > 0 && name[0] == '-')
|
|
hostname = name + 1;
|
|
|
|
if (sethostname(hostname, strlen(hostname)) < 0) {
|
|
virReportSystemError(errno, "%s", _("Failed to set hostname"));
|
|
goto cleanup;
|
|
}
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
VIR_FREE(name);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* lxcContainerChild:
|
|
* @data: pointer to container arguments
|
|
*
|
|
* This function is run in the process clone()'d in lxcStartContainer.
|
|
* Perform a number of container setup tasks:
|
|
* Setup container file system
|
|
* mount container /proc
|
|
* Then exec's the container init
|
|
*
|
|
* Returns 0 on success or -1 in case of error
|
|
*/
|
|
static int lxcContainerChild(void *data)
|
|
{
|
|
lxc_child_argv_t *argv = data;
|
|
virDomainDefPtr vmDef = argv->config;
|
|
int ttyfd = -1;
|
|
int ret = -1;
|
|
char *ttyPath = NULL;
|
|
virDomainFSDefPtr root;
|
|
virCommandPtr cmd = NULL;
|
|
int hasReboot;
|
|
gid_t *groups = NULL;
|
|
int ngroups;
|
|
|
|
if (NULL == vmDef) {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR,
|
|
"%s", _("lxcChild() passed invalid vm definition"));
|
|
goto cleanup;
|
|
}
|
|
|
|
if (lxcAttachNS(argv->nsInheritFDs) < 0) {
|
|
virReportError(VIR_ERR_SYSTEM_ERROR, "%s",
|
|
_("failed to attach the namespace"));
|
|
return -1;
|
|
}
|
|
|
|
/* Wait for controller to finish setup tasks, including
|
|
* things like move of network interfaces, uid/gid mapping
|
|
*/
|
|
if (lxcContainerWaitForContinue(argv->monitor) < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to read the container continue message"));
|
|
goto cleanup;
|
|
}
|
|
VIR_DEBUG("Received container continue message");
|
|
|
|
if ((hasReboot = lxcContainerHasReboot()) < 0)
|
|
goto cleanup;
|
|
|
|
cmd = lxcContainerBuildInitCmd(vmDef,
|
|
argv->ttyPaths,
|
|
argv->nttyPaths);
|
|
virCommandWriteArgLog(cmd, 1);
|
|
|
|
if (lxcContainerSetID(vmDef) < 0)
|
|
goto cleanup;
|
|
|
|
root = virDomainGetFilesystemForTarget(vmDef, "/");
|
|
|
|
if (argv->nttyPaths) {
|
|
const char *tty = argv->ttyPaths[0];
|
|
if (STRPREFIX(tty, "/dev/pts/"))
|
|
tty += strlen("/dev/pts/");
|
|
if (virAsprintf(&ttyPath, "%s/%s.devpts/%s",
|
|
LXC_STATE_DIR, vmDef->name, tty) < 0)
|
|
goto cleanup;
|
|
} else {
|
|
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
|
|
_("At least one tty is required"));
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_DEBUG("Container TTY path: %s", ttyPath);
|
|
|
|
ttyfd = open(ttyPath, O_RDWR);
|
|
if (ttyfd < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to open tty %s"),
|
|
ttyPath);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (lxcContainerResolveAllSymlinks(vmDef) < 0)
|
|
goto cleanup;
|
|
|
|
VIR_DEBUG("Setting up pivot");
|
|
if (lxcContainerSetupPivotRoot(vmDef, root,
|
|
argv->ttyPaths, argv->nttyPaths,
|
|
argv->securityDriver) < 0)
|
|
goto cleanup;
|
|
|
|
if (!virFileExists(vmDef->os.init)) {
|
|
virReportSystemError(errno,
|
|
_("cannot find init path '%s' relative to container root"),
|
|
vmDef->os.init);
|
|
goto cleanup;
|
|
}
|
|
|
|
if (lxcContainerSetUserGroup(cmd, vmDef, argv->ttyPaths[0]) < 0)
|
|
goto cleanup;
|
|
|
|
/* rename and enable interfaces */
|
|
if (lxcContainerRenameAndEnableInterfaces(vmDef,
|
|
argv->nveths,
|
|
argv->veths) < 0) {
|
|
goto cleanup;
|
|
}
|
|
|
|
if (lxcContainerSetHostname(vmDef) < 0)
|
|
goto cleanup;
|
|
|
|
|
|
/* drop a set of root capabilities */
|
|
if (lxcContainerDropCapabilities(vmDef, !!hasReboot) < 0)
|
|
goto cleanup;
|
|
|
|
if (lxcContainerSendContinue(argv->handshakefd) < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to send continue signal to controller"));
|
|
goto cleanup;
|
|
}
|
|
|
|
VIR_DEBUG("Setting up security labeling");
|
|
if (virSecurityManagerSetProcessLabel(argv->securityDriver, vmDef) < 0)
|
|
goto cleanup;
|
|
|
|
VIR_DEBUG("Setting up inherited FDs");
|
|
VIR_FORCE_CLOSE(argv->handshakefd);
|
|
VIR_FORCE_CLOSE(argv->monitor);
|
|
if (lxcContainerSetupFDs(&ttyfd,
|
|
argv->npassFDs, argv->passFDs) < 0)
|
|
goto cleanup;
|
|
|
|
/* Make init process of the container the leader of the new session.
|
|
* That is needed when checkpointing container.
|
|
*/
|
|
if (setsid() < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Unable to become session leader"));
|
|
goto cleanup;
|
|
}
|
|
|
|
/* TODO is it safe to call it here or should this call be moved in
|
|
* front of the clone() as otherwise there might be a risk for a
|
|
* deadlock */
|
|
if ((ngroups = virGetGroupList(virCommandGetUID(cmd), virCommandGetGID(cmd),
|
|
&groups)) < 0)
|
|
goto cleanup;
|
|
|
|
ret = 0;
|
|
cleanup:
|
|
VIR_FREE(ttyPath);
|
|
VIR_FORCE_CLOSE(ttyfd);
|
|
VIR_FORCE_CLOSE(argv->monitor);
|
|
VIR_FORCE_CLOSE(argv->handshakefd);
|
|
|
|
if (ret == 0) {
|
|
VIR_DEBUG("Executing init binary");
|
|
/* this function will only return if an error occurred */
|
|
ret = virCommandExec(cmd, groups, ngroups);
|
|
}
|
|
|
|
if (ret != 0) {
|
|
VIR_DEBUG("Tearing down container");
|
|
fprintf(stderr,
|
|
_("Failure in libvirt_lxc startup: %s\n"),
|
|
virGetLastErrorMessage());
|
|
}
|
|
|
|
VIR_FREE(groups);
|
|
virCommandFree(cmd);
|
|
return ret;
|
|
}
|
|
|
|
static int userns_required(virDomainDefPtr def)
|
|
{
|
|
return def->idmap.uidmap && def->idmap.gidmap;
|
|
}
|
|
|
|
virArch lxcContainerGetAlt32bitArch(virArch arch)
|
|
{
|
|
/* Any Linux 64bit arch which has a 32bit
|
|
* personality available should be listed here */
|
|
if (arch == VIR_ARCH_X86_64)
|
|
return VIR_ARCH_I686;
|
|
if (arch == VIR_ARCH_S390X)
|
|
return VIR_ARCH_S390;
|
|
if (arch == VIR_ARCH_PPC64)
|
|
return VIR_ARCH_PPC;
|
|
if (arch == VIR_ARCH_PARISC64)
|
|
return VIR_ARCH_PARISC;
|
|
if (arch == VIR_ARCH_SPARC64)
|
|
return VIR_ARCH_SPARC;
|
|
if (arch == VIR_ARCH_MIPS64)
|
|
return VIR_ARCH_MIPS;
|
|
if (arch == VIR_ARCH_MIPS64EL)
|
|
return VIR_ARCH_MIPSEL;
|
|
if (arch == VIR_ARCH_AARCH64)
|
|
return VIR_ARCH_ARMV7L;
|
|
|
|
return VIR_ARCH_NONE;
|
|
}
|
|
|
|
|
|
/**
|
|
* lxcContainerStart:
|
|
* @def: pointer to virtual machine structure
|
|
* @nveths: number of interfaces
|
|
* @veths: interface names
|
|
* @control: control FD to the container
|
|
* @ttyPath: path of tty to set as the container console
|
|
*
|
|
* Starts a container process by calling clone() with the namespace flags
|
|
*
|
|
* Returns PID of container on success or -1 in case of error
|
|
*/
|
|
int lxcContainerStart(virDomainDefPtr def,
|
|
virSecurityManagerPtr securityDriver,
|
|
size_t nveths,
|
|
char **veths,
|
|
size_t npassFDs,
|
|
int *passFDs,
|
|
int control,
|
|
int handshakefd,
|
|
int *nsInheritFDs,
|
|
size_t nttyPaths,
|
|
char **ttyPaths)
|
|
{
|
|
pid_t pid;
|
|
int cflags;
|
|
int stacksize = getpagesize() * 4;
|
|
char *stack, *stacktop;
|
|
lxc_child_argv_t args = {
|
|
.config = def,
|
|
.securityDriver = securityDriver,
|
|
.nveths = nveths,
|
|
.veths = veths,
|
|
.npassFDs = npassFDs,
|
|
.passFDs = passFDs,
|
|
.monitor = control,
|
|
.nttyPaths = nttyPaths,
|
|
.ttyPaths = ttyPaths,
|
|
.handshakefd = handshakefd,
|
|
.nsInheritFDs = nsInheritFDs,
|
|
};
|
|
|
|
/* allocate a stack for the container */
|
|
if (VIR_ALLOC_N(stack, stacksize) < 0)
|
|
return -1;
|
|
|
|
stacktop = stack + stacksize;
|
|
|
|
cflags = CLONE_NEWPID|CLONE_NEWNS|SIGCHLD;
|
|
|
|
if (userns_required(def)) {
|
|
if (virProcessNamespaceAvailable(VIR_PROCESS_NAMESPACE_USER) < 0) {
|
|
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
|
|
_("Kernel doesn't support user namespace"));
|
|
VIR_FREE(stack);
|
|
return -1;
|
|
}
|
|
VIR_DEBUG("Enable user namespace");
|
|
cflags |= CLONE_NEWUSER;
|
|
}
|
|
if (!nsInheritFDs || nsInheritFDs[VIR_LXC_DOMAIN_NAMESPACE_SHARENET] == -1) {
|
|
if (lxcNeedNetworkNamespace(def)) {
|
|
VIR_DEBUG("Enable network namespaces");
|
|
cflags |= CLONE_NEWNET;
|
|
}
|
|
} else {
|
|
if (lxcNeedNetworkNamespace(def)) {
|
|
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
|
|
_("Config asks for inherit net namespace "
|
|
"as well as private network interfaces"));
|
|
VIR_FREE(stack);
|
|
return -1;
|
|
}
|
|
VIR_DEBUG("Inheriting a net namespace");
|
|
}
|
|
|
|
if (!nsInheritFDs || nsInheritFDs[VIR_LXC_DOMAIN_NAMESPACE_SHAREIPC] == -1) {
|
|
cflags |= CLONE_NEWIPC;
|
|
} else {
|
|
VIR_DEBUG("Inheriting an IPC namespace");
|
|
}
|
|
|
|
if (!nsInheritFDs || nsInheritFDs[VIR_LXC_DOMAIN_NAMESPACE_SHAREUTS] == -1) {
|
|
cflags |= CLONE_NEWUTS;
|
|
} else {
|
|
VIR_DEBUG("Inheriting a UTS namespace");
|
|
}
|
|
|
|
VIR_DEBUG("Cloning container init process");
|
|
pid = clone(lxcContainerChild, stacktop, cflags, &args);
|
|
VIR_FREE(stack);
|
|
VIR_DEBUG("clone() completed, new container PID is %d", pid);
|
|
|
|
if (pid < 0) {
|
|
virReportSystemError(errno, "%s",
|
|
_("Failed to run clone container"));
|
|
return -1;
|
|
}
|
|
|
|
return pid;
|
|
}
|
|
|
|
int lxcContainerChown(virDomainDefPtr def, const char *path)
|
|
{
|
|
uid_t uid;
|
|
gid_t gid;
|
|
|
|
if (!def->idmap.uidmap)
|
|
return 0;
|
|
|
|
uid = def->idmap.uidmap[0].target;
|
|
gid = def->idmap.gidmap[0].target;
|
|
|
|
if (chown(path, uid, gid) < 0) {
|
|
virReportSystemError(errno,
|
|
_("Failed to change owner of %s to %u:%u"),
|
|
path, uid, gid);
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|