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")) {
235 int detect_container(const char **id) {
237 static thread_local int cached_found = -1;
238 static thread_local const char *cached_id = NULL;
240 _cleanup_free_ char *m = NULL;
241 const char *_id = NULL, *e = NULL;
244 if (_likely_(cached_found >= 0)) {
252 /* /proc/vz exists in container and outside of the container,
253 * /proc/bc only outside of the container. */
254 if (access("/proc/vz", F_OK) >= 0 &&
255 access("/proc/bc", F_OK) < 0) {
262 /* If we are PID 1 we can just check our own
263 * environment variable */
265 e = getenv("container");
272 /* Otherwise, PID 1 dropped this information into a
273 * file in /run. This is better than accessing
274 * /proc/1/environ, since we don't need CAP_SYS_PTRACE
277 r = read_one_line_file("/run/systemd/container", &m);
288 /* We only recognize a selected few here, since we want to
289 * enforce a redacted namespace */
292 else if (streq(e, "lxc-libvirt"))
294 else if (streq(e, "systemd-nspawn"))
295 _id = "systemd-nspawn";
311 /* Returns a short identifier for the various VM/container implementations */
312 int detect_virtualization(const char **id) {
315 r = detect_container(id);
319 return VIRTUALIZATION_CONTAINER;
325 return VIRTUALIZATION_VM;
327 return VIRTUALIZATION_NONE;