summaryrefslogtreecommitdiff
path: root/src/libbasic/virt.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libbasic/virt.c')
-rw-r--r--src/libbasic/virt.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/src/libbasic/virt.c b/src/libbasic/virt.c
new file mode 100644
index 0000000000..19b6318e3d
--- /dev/null
+++ b/src/libbasic/virt.c
@@ -0,0 +1,462 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2011 Lennart Poettering
+
+ systemd 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.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "macro.h"
+#include "process-util.h"
+#include "stat-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "virt.h"
+
+static int detect_vm_cpuid(void) {
+
+ /* CPUID is an x86 specific interface. */
+#if defined(__i386__) || defined(__x86_64__)
+
+ static const struct {
+ const char *cpuid;
+ int id;
+ } cpuid_vendor_table[] = {
+ { "XenVMMXenVMM", VIRTUALIZATION_XEN },
+ { "KVMKVMKVM", VIRTUALIZATION_KVM },
+ /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
+ { "VMwareVMware", VIRTUALIZATION_VMWARE },
+ /* http://msdn.microsoft.com/en-us/library/ff542428.aspx */
+ { "Microsoft Hv", VIRTUALIZATION_MICROSOFT },
+ };
+
+ uint32_t eax, ecx;
+ bool hypervisor;
+
+ /* http://lwn.net/Articles/301888/ */
+
+#if defined (__i386__)
+#define REG_a "eax"
+#define REG_b "ebx"
+#elif defined (__amd64__)
+#define REG_a "rax"
+#define REG_b "rbx"
+#endif
+
+ /* First detect whether there is a hypervisor */
+ eax = 1;
+ __asm__ __volatile__ (
+ /* ebx/rbx is being used for PIC! */
+ " push %%"REG_b" \n\t"
+ " cpuid \n\t"
+ " pop %%"REG_b" \n\t"
+
+ : "=a" (eax), "=c" (ecx)
+ : "0" (eax)
+ );
+
+ hypervisor = !!(ecx & 0x80000000U);
+
+ if (hypervisor) {
+ union {
+ uint32_t sig32[3];
+ char text[13];
+ } sig = {};
+ unsigned j;
+
+ /* There is a hypervisor, see what it is */
+ eax = 0x40000000U;
+ __asm__ __volatile__ (
+ /* ebx/rbx is being used for PIC! */
+ " push %%"REG_b" \n\t"
+ " cpuid \n\t"
+ " mov %%ebx, %1 \n\t"
+ " pop %%"REG_b" \n\t"
+
+ : "=a" (eax), "=r" (sig.sig32[0]), "=c" (sig.sig32[1]), "=d" (sig.sig32[2])
+ : "0" (eax)
+ );
+
+ for (j = 0; j < ELEMENTSOF(cpuid_vendor_table); j ++)
+ if (streq(sig.text, cpuid_vendor_table[j].cpuid))
+ return cpuid_vendor_table[j].id;
+
+ return VIRTUALIZATION_VM_OTHER;
+ }
+#endif
+
+ return VIRTUALIZATION_NONE;
+}
+
+static int detect_vm_device_tree(void) {
+#if defined(__arm__) || defined(__aarch64__) || defined(__powerpc__) || defined(__powerpc64__)
+ _cleanup_free_ char *hvtype = NULL;
+ int r;
+
+ r = read_one_line_file("/proc/device-tree/hypervisor/compatible", &hvtype);
+ if (r == -ENOENT) {
+ _cleanup_closedir_ DIR *dir = NULL;
+ struct dirent *dent;
+
+ dir = opendir("/proc/device-tree");
+ if (!dir) {
+ if (errno == ENOENT)
+ return VIRTUALIZATION_NONE;
+ return -errno;
+ }
+
+ FOREACH_DIRENT(dent, dir, return -errno)
+ if (strstr(dent->d_name, "fw-cfg"))
+ return VIRTUALIZATION_QEMU;
+
+ return VIRTUALIZATION_NONE;
+ } else if (r < 0)
+ return r;
+
+ if (streq(hvtype, "linux,kvm"))
+ return VIRTUALIZATION_KVM;
+ else if (strstr(hvtype, "xen"))
+ return VIRTUALIZATION_XEN;
+ else
+ return VIRTUALIZATION_VM_OTHER;
+#else
+ return VIRTUALIZATION_NONE;
+#endif
+}
+
+static int detect_vm_dmi(void) {
+#if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__aarch64__)
+
+ static const char *const dmi_vendors[] = {
+ "/sys/class/dmi/id/product_name", /* Test this before sys_vendor to detect KVM over QEMU */
+ "/sys/class/dmi/id/sys_vendor",
+ "/sys/class/dmi/id/board_vendor",
+ "/sys/class/dmi/id/bios_vendor"
+ };
+
+ static const struct {
+ const char *vendor;
+ int id;
+ } dmi_vendor_table[] = {
+ { "KVM", VIRTUALIZATION_KVM },
+ { "QEMU", VIRTUALIZATION_QEMU },
+ /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
+ { "VMware", VIRTUALIZATION_VMWARE },
+ { "VMW", VIRTUALIZATION_VMWARE },
+ { "innotek GmbH", VIRTUALIZATION_ORACLE },
+ { "Xen", VIRTUALIZATION_XEN },
+ { "Bochs", VIRTUALIZATION_BOCHS },
+ { "Parallels", VIRTUALIZATION_PARALLELS },
+ };
+ unsigned i;
+ int r;
+
+ for (i = 0; i < ELEMENTSOF(dmi_vendors); i++) {
+ _cleanup_free_ char *s = NULL;
+ unsigned j;
+
+ r = read_one_line_file(dmi_vendors[i], &s);
+ if (r < 0) {
+ if (r == -ENOENT)
+ continue;
+
+ return r;
+ }
+
+ for (j = 0; j < ELEMENTSOF(dmi_vendor_table); j++)
+ if (startswith(s, dmi_vendor_table[j].vendor))
+ return dmi_vendor_table[j].id;
+ }
+#endif
+
+ return VIRTUALIZATION_NONE;
+}
+
+static int detect_vm_xen(void) {
+ _cleanup_free_ char *domcap = NULL;
+ char *cap, *i;
+ int r;
+
+ r = read_one_line_file("/proc/xen/capabilities", &domcap);
+ if (r == -ENOENT)
+ return VIRTUALIZATION_NONE;
+
+ i = domcap;
+ while ((cap = strsep(&i, ",")))
+ if (streq(cap, "control_d"))
+ break;
+
+ return cap ? VIRTUALIZATION_NONE : VIRTUALIZATION_XEN;
+}
+
+static int detect_vm_hypervisor(void) {
+ _cleanup_free_ char *hvtype = NULL;
+ int r;
+
+ r = read_one_line_file("/sys/hypervisor/type", &hvtype);
+ if (r == -ENOENT)
+ return VIRTUALIZATION_NONE;
+ if (r < 0)
+ return r;
+
+ if (streq(hvtype, "xen"))
+ return VIRTUALIZATION_XEN;
+ else
+ return VIRTUALIZATION_VM_OTHER;
+}
+
+static int detect_vm_uml(void) {
+ _cleanup_free_ char *cpuinfo_contents = NULL;
+ int r;
+
+ /* Detect User-Mode Linux by reading /proc/cpuinfo */
+ r = read_full_file("/proc/cpuinfo", &cpuinfo_contents, NULL);
+ if (r < 0)
+ return r;
+ if (strstr(cpuinfo_contents, "\nvendor_id\t: User Mode Linux\n"))
+ return VIRTUALIZATION_UML;
+
+ return VIRTUALIZATION_NONE;
+}
+
+static int detect_vm_zvm(void) {
+
+#if defined(__s390__)
+ _cleanup_free_ char *t = NULL;
+ int r;
+
+ r = get_proc_field("/proc/sysinfo", "VM00 Control Program", WHITESPACE, &t);
+ if (r == -ENOENT)
+ return VIRTUALIZATION_NONE;
+ if (r < 0)
+ return r;
+
+ if (streq(t, "z/VM"))
+ return VIRTUALIZATION_ZVM;
+ else
+ return VIRTUALIZATION_KVM;
+#else
+ return VIRTUALIZATION_NONE;
+#endif
+}
+
+/* Returns a short identifier for the various VM implementations */
+int detect_vm(void) {
+ static thread_local int cached_found = _VIRTUALIZATION_INVALID;
+ int r;
+
+ if (cached_found >= 0)
+ return cached_found;
+
+ /* We have to use the correct order here:
+ * Some virtualization technologies do use KVM hypervisor but are
+ * expected to be detected as something else. So detect DMI first.
+ *
+ * An example is Virtualbox since version 5.0, which uses KVM backend.
+ * Detection via DMI works corretly, the CPU ID would find KVM
+ * only. */
+ r = detect_vm_dmi();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ r = detect_vm_cpuid();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ /* x86 xen will most likely be detected by cpuid. If not (most likely
+ * because we're not an x86 guest), then we should try the xen capabilities
+ * file next. If that's not found, then we check for the high-level
+ * hypervisor sysfs file:
+ *
+ * https://bugs.freedesktop.org/show_bug.cgi?id=77271 */
+
+ r = detect_vm_xen();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ r = detect_vm_hypervisor();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ r = detect_vm_device_tree();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ r = detect_vm_uml();
+ if (r < 0)
+ return r;
+ if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ r = detect_vm_zvm();
+ if (r < 0)
+ return r;
+
+finish:
+ cached_found = r;
+ return r;
+}
+
+int detect_container(void) {
+
+ static const struct {
+ const char *value;
+ int id;
+ } value_table[] = {
+ { "lxc", VIRTUALIZATION_LXC },
+ { "lxc-libvirt", VIRTUALIZATION_LXC_LIBVIRT },
+ { "systemd-nspawn", VIRTUALIZATION_SYSTEMD_NSPAWN },
+ { "docker", VIRTUALIZATION_DOCKER },
+ { "rkt", VIRTUALIZATION_RKT },
+ };
+
+ static thread_local int cached_found = _VIRTUALIZATION_INVALID;
+ _cleanup_free_ char *m = NULL;
+ const char *e = NULL;
+ unsigned j;
+ int r;
+
+ if (cached_found >= 0)
+ return cached_found;
+
+ /* /proc/vz exists in container and outside of the container,
+ * /proc/bc only outside of the container. */
+ if (access("/proc/vz", F_OK) >= 0 &&
+ access("/proc/bc", F_OK) < 0) {
+ r = VIRTUALIZATION_OPENVZ;
+ goto finish;
+ }
+
+ if (getpid() == 1) {
+ /* If we are PID 1 we can just check our own
+ * environment variable */
+
+ e = getenv("container");
+ if (isempty(e)) {
+ r = VIRTUALIZATION_NONE;
+ goto finish;
+ }
+ } else {
+
+ /* Otherwise, PID 1 dropped this information into a
+ * file in /run. This is better than accessing
+ * /proc/1/environ, since we don't need CAP_SYS_PTRACE
+ * for that. */
+
+ r = read_one_line_file("/run/systemd/container", &m);
+ if (r == -ENOENT) {
+
+ /* Fallback for cases where PID 1 was not
+ * systemd (for example, cases where
+ * init=/bin/sh is used. */
+
+ r = getenv_for_pid(1, "container", &m);
+ if (r <= 0) {
+
+ /* If that didn't work, give up,
+ * assume no container manager.
+ *
+ * Note: This means we still cannot
+ * detect containers if init=/bin/sh
+ * is passed but privileges dropped,
+ * as /proc/1/environ is only readable
+ * with privileges. */
+
+ r = VIRTUALIZATION_NONE;
+ goto finish;
+ }
+ }
+ if (r < 0)
+ return r;
+
+ e = m;
+ }
+
+ for (j = 0; j < ELEMENTSOF(value_table); j++)
+ if (streq(e, value_table[j].value)) {
+ r = value_table[j].id;
+ goto finish;
+ }
+
+ r = VIRTUALIZATION_CONTAINER_OTHER;
+
+finish:
+ cached_found = r;
+ return r;
+}
+
+int detect_virtualization(void) {
+ int r;
+
+ r = detect_container();
+ if (r != 0)
+ return r;
+
+ return detect_vm();
+}
+
+int running_in_chroot(void) {
+ int ret;
+
+ ret = files_same("/proc/1/root", "/");
+ if (ret < 0)
+ return ret;
+
+ return ret == 0;
+}
+
+static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
+ [VIRTUALIZATION_NONE] = "none",
+ [VIRTUALIZATION_KVM] = "kvm",
+ [VIRTUALIZATION_QEMU] = "qemu",
+ [VIRTUALIZATION_BOCHS] = "bochs",
+ [VIRTUALIZATION_XEN] = "xen",
+ [VIRTUALIZATION_UML] = "uml",
+ [VIRTUALIZATION_VMWARE] = "vmware",
+ [VIRTUALIZATION_ORACLE] = "oracle",
+ [VIRTUALIZATION_MICROSOFT] = "microsoft",
+ [VIRTUALIZATION_ZVM] = "zvm",
+ [VIRTUALIZATION_PARALLELS] = "parallels",
+ [VIRTUALIZATION_VM_OTHER] = "vm-other",
+
+ [VIRTUALIZATION_SYSTEMD_NSPAWN] = "systemd-nspawn",
+ [VIRTUALIZATION_LXC_LIBVIRT] = "lxc-libvirt",
+ [VIRTUALIZATION_LXC] = "lxc",
+ [VIRTUALIZATION_OPENVZ] = "openvz",
+ [VIRTUALIZATION_DOCKER] = "docker",
+ [VIRTUALIZATION_RKT] = "rkt",
+ [VIRTUALIZATION_CONTAINER_OTHER] = "container-other",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(virtualization, int);