1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2011 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
27 #include "process-util.h"
31 static int detect_vm_cpuid(const char **_id) {
33 /* Both CPUID and DMI are x86 specific interfaces... */
34 #if defined(__i386__) || defined(__x86_64__)
36 static const char cpuid_vendor_table[] =
37 "XenVMMXenVMM\0" "xen\0"
39 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
40 "VMwareVMware\0" "vmware\0"
41 /* http://msdn.microsoft.com/en-us/library/ff542428.aspx */
42 "Microsoft Hv\0" "microsoft\0";
52 /* http://lwn.net/Articles/301888/ */
54 #if defined (__i386__)
57 #elif defined (__amd64__)
62 /* First detect whether there is a hypervisor */
64 __asm__ __volatile__ (
65 /* ebx/rbx is being used for PIC! */
66 " push %%"REG_b" \n\t"
70 : "=a" (eax), "=c" (ecx)
74 hypervisor = !!(ecx & 0x80000000U);
78 /* There is a hypervisor, see what it is */
80 __asm__ __volatile__ (
81 /* ebx/rbx is being used for PIC! */
82 " push %%"REG_b" \n\t"
87 : "=a" (eax), "=r" (sig.sig32[0]), "=c" (sig.sig32[1]), "=d" (sig.sig32[2])
91 NULSTR_FOREACH_PAIR(j, k, cpuid_vendor_table)
92 if (streq(sig.text, j)) {
105 static int detect_vm_devicetree(const char **_id) {
106 #if defined(__arm__) || defined(__aarch64__) || defined(__powerpc__) || defined(__powerpc64__)
107 _cleanup_free_ char *hvtype = NULL;
110 r = read_one_line_file("/proc/device-tree/hypervisor/compatible", &hvtype);
112 if (streq(hvtype, "linux,kvm")) {
115 } else if (strstr(hvtype, "xen")) {
119 } else if (r == -ENOENT) {
120 _cleanup_closedir_ DIR *dir = NULL;
123 dir = opendir("/proc/device-tree");
130 FOREACH_DIRENT(dent, dir, return -errno) {
131 if (strstr(dent->d_name, "fw-cfg")) {
141 static int detect_vm_dmi(const char **_id) {
143 /* Both CPUID and DMI are x86 specific interfaces... */
144 #if defined(__i386__) || defined(__x86_64__)
146 static const char *const dmi_vendors[] = {
147 "/sys/class/dmi/id/sys_vendor",
148 "/sys/class/dmi/id/board_vendor",
149 "/sys/class/dmi/id/bios_vendor"
152 static const char dmi_vendor_table[] =
154 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
155 "VMware\0" "vmware\0"
157 "innotek GmbH\0" "oracle\0"
162 for (i = 0; i < ELEMENTSOF(dmi_vendors); i++) {
163 _cleanup_free_ char *s = NULL;
167 r = read_one_line_file(dmi_vendors[i], &s);
175 NULSTR_FOREACH_PAIR(j, k, dmi_vendor_table)
176 if (startswith(s, j)) {
186 /* Returns a short identifier for the various VM implementations */
187 int detect_vm(const char **id) {
188 _cleanup_free_ char *domcap = NULL, *cpuinfo_contents = NULL;
189 static thread_local int cached_found = -1;
190 static thread_local const char *cached_id = NULL;
191 const char *_id = NULL;
194 if (_likely_(cached_found >= 0)) {
202 /* Try xen capabilities file first, if not found try high-level hypervisor sysfs file:
204 * https://bugs.freedesktop.org/show_bug.cgi?id=77271 */
205 r = read_one_line_file("/proc/xen/capabilities", &domcap);
207 char *cap, *i = domcap;
209 while ((cap = strsep(&i, ",")))
210 if (streq(cap, "control_d"))
220 } else if (r == -ENOENT) {
221 _cleanup_free_ char *hvtype = NULL;
223 r = read_one_line_file("/sys/hypervisor/type", &hvtype);
225 if (streq(hvtype, "xen")) {
230 } else if (r != -ENOENT)
235 /* this will set _id to "other" and return 0 for unknown hypervisors */
236 r = detect_vm_cpuid(&_id);
240 r = detect_vm_dmi(&_id);
244 r = detect_vm_devicetree(&_id);
254 /* Detect User-Mode Linux by reading /proc/cpuinfo */
255 r = read_full_file("/proc/cpuinfo", &cpuinfo_contents, NULL);
258 if (strstr(cpuinfo_contents, "\nvendor_id\t: User Mode Linux\n")) {
264 #if defined(__s390__)
266 _cleanup_free_ char *t = NULL;
268 r = get_status_field("/proc/sysinfo", "VM00 Control Program:", &t);
270 if (streq(t, "z/VM"))
293 int detect_container(const char **id) {
295 static thread_local int cached_found = -1;
296 static thread_local const char *cached_id = NULL;
298 _cleanup_free_ char *m = NULL;
299 const char *_id = NULL, *e = NULL;
302 if (_likely_(cached_found >= 0)) {
310 /* /proc/vz exists in container and outside of the container,
311 * /proc/bc only outside of the container. */
312 if (access("/proc/vz", F_OK) >= 0 &&
313 access("/proc/bc", F_OK) < 0) {
320 /* If we are PID 1 we can just check our own
321 * environment variable */
323 e = getenv("container");
330 /* Otherwise, PID 1 dropped this information into a
331 * file in /run. This is better than accessing
332 * /proc/1/environ, since we don't need CAP_SYS_PTRACE
335 r = read_one_line_file("/run/systemd/container", &m);
338 /* Fallback for cases where PID 1 was not
339 * systemd (for example, cases where
340 * init=/bin/sh is used. */
342 r = getenv_for_pid(1, "container", &m);
345 /* If that didn't work, give up,
346 * assume no container manager.
348 * Note: This means we still cannot
349 * detect containers if init=/bin/sh
350 * is passed but privileges dropped,
351 * as /proc/1/environ is only readable
352 * with privileges. */
364 /* We only recognize a selected few here, since we want to
365 * enforce a redacted namespace */
368 else if (streq(e, "lxc-libvirt"))
370 else if (streq(e, "systemd-nspawn"))
371 _id = "systemd-nspawn";
372 else if (streq(e, "docker"))
389 /* Returns a short identifier for the various VM/container implementations */
390 int detect_virtualization(const char **id) {
393 r = detect_container(id);
397 return VIRTUALIZATION_CONTAINER;
403 return VIRTUALIZATION_VM;
405 return VIRTUALIZATION_NONE;