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/>.
30 static int detect_vm_cpuid(const char **_id) {
32 /* Both CPUID and DMI are x86 specific interfaces... */
33 #if defined(__i386__) || defined(__x86_64__)
35 static const char cpuid_vendor_table[] =
36 "XenVMMXenVMM\0" "xen\0"
38 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
39 "VMwareVMware\0" "vmware\0"
40 /* http://msdn.microsoft.com/en-us/library/ff542428.aspx */
41 "Microsoft Hv\0" "microsoft\0";
51 /* http://lwn.net/Articles/301888/ */
53 #if defined (__i386__)
56 #elif defined (__amd64__)
61 /* First detect whether there is a hypervisor */
63 __asm__ __volatile__ (
64 /* ebx/rbx is being used for PIC! */
65 " push %%"REG_b" \n\t"
69 : "=a" (eax), "=c" (ecx)
73 hypervisor = !!(ecx & 0x80000000U);
77 /* There is a hypervisor, see what it is */
79 __asm__ __volatile__ (
80 /* ebx/rbx is being used for PIC! */
81 " push %%"REG_b" \n\t"
86 : "=a" (eax), "=r" (sig.sig32[0]), "=c" (sig.sig32[1]), "=d" (sig.sig32[2])
90 NULSTR_FOREACH_PAIR(j, k, cpuid_vendor_table)
91 if (streq(sig.text, j)) {
104 static int detect_vm_dmi(const char **_id) {
106 /* Both CPUID and DMI are x86 specific interfaces... */
107 #if defined(__i386__) || defined(__x86_64__)
109 static const char *const dmi_vendors[] = {
110 "/sys/class/dmi/id/sys_vendor",
111 "/sys/class/dmi/id/board_vendor",
112 "/sys/class/dmi/id/bios_vendor"
115 static const char dmi_vendor_table[] =
117 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
118 "VMware\0" "vmware\0"
120 "innotek GmbH\0" "oracle\0"
125 for (i = 0; i < ELEMENTSOF(dmi_vendors); i++) {
126 _cleanup_free_ char *s = NULL;
130 r = read_one_line_file(dmi_vendors[i], &s);
138 NULSTR_FOREACH_PAIR(j, k, dmi_vendor_table)
139 if (startswith(s, j)) {
149 /* Returns a short identifier for the various VM implementations */
150 int detect_vm(const char **id) {
151 _cleanup_free_ char *domcap = NULL, *cpuinfo_contents = NULL;
152 static thread_local int cached_found = -1;
153 static thread_local const char *cached_id = NULL;
154 const char *_id = NULL;
157 if (_likely_(cached_found >= 0)) {
165 /* Try xen capabilities file first, if not found try high-level hypervisor sysfs file:
167 * https://bugs.freedesktop.org/show_bug.cgi?id=77271 */
168 r = read_one_line_file("/proc/xen/capabilities", &domcap);
170 char *cap, *i = domcap;
172 while ((cap = strsep(&i, ",")))
173 if (streq(cap, "control_d"))
183 } else if (r == -ENOENT) {
184 _cleanup_free_ char *hvtype = NULL;
186 r = read_one_line_file("/sys/hypervisor/type", &hvtype);
188 if (streq(hvtype, "xen")) {
193 } else if (r != -ENOENT)
198 /* this will set _id to "other" and return 0 for unknown hypervisors */
199 r = detect_vm_cpuid(&_id);
203 r = detect_vm_dmi(&_id);
213 /* Detect User-Mode Linux by reading /proc/cpuinfo */
214 r = read_full_file("/proc/cpuinfo", &cpuinfo_contents, NULL);
217 if (strstr(cpuinfo_contents, "\nvendor_id\t: User Mode Linux\n")) {
223 #if defined(__s390__)
225 _cleanup_free_ char *t = NULL;
227 r = get_status_field("/proc/sysinfo", "VM00 Control Program:", &t);
229 if (streq(t, "z/VM"))
252 int detect_container(const char **id) {
254 static thread_local int cached_found = -1;
255 static thread_local const char *cached_id = NULL;
257 _cleanup_free_ char *m = NULL;
258 const char *_id = NULL, *e = NULL;
261 if (_likely_(cached_found >= 0)) {
269 /* /proc/vz exists in container and outside of the container,
270 * /proc/bc only outside of the container. */
271 if (access("/proc/vz", F_OK) >= 0 &&
272 access("/proc/bc", F_OK) < 0) {
279 /* If we are PID 1 we can just check our own
280 * environment variable */
282 e = getenv("container");
289 /* Otherwise, PID 1 dropped this information into a
290 * file in /run. This is better than accessing
291 * /proc/1/environ, since we don't need CAP_SYS_PTRACE
294 r = read_one_line_file("/run/systemd/container", &m);
305 /* We only recognize a selected few here, since we want to
306 * enforce a redacted namespace */
309 else if (streq(e, "lxc-libvirt"))
311 else if (streq(e, "systemd-nspawn"))
312 _id = "systemd-nspawn";
328 /* Returns a short identifier for the various VM/container implementations */
329 int detect_virtualization(const char **id) {
332 r = detect_container(id);
336 return VIRTUALIZATION_CONTAINER;
342 return VIRTUALIZATION_VM;
344 return VIRTUALIZATION_NONE;