+/* SPDX-License-Identifier: LGPL-2.1+ */
/***
- 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/>.
***/
+#if defined(__i386__) || defined(__x86_64__)
+//#include <cpuid.h>
+#endif
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include "alloc-util.h"
#include "dirent-util.h"
+#include "env-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "macro.h"
} cpuid_vendor_table[] = {
{ "XenVMMXenVMM", VIRTUALIZATION_XEN },
{ "KVMKVMKVM", VIRTUALIZATION_KVM },
+ { "TCGTCGTCGTCG", VIRTUALIZATION_QEMU },
/* 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 */
+ /* https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs */
{ "Microsoft Hv", VIRTUALIZATION_MICROSOFT },
/* https://wiki.freebsd.org/bhyve */
{ "bhyve bhyve ", VIRTUALIZATION_BHYVE },
+ { "QNXQVMBSQG", VIRTUALIZATION_QNX },
};
- uint32_t eax, ecx;
+ uint32_t eax, ebx, ecx, edx;
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)
- );
+ if (__get_cpuid(1, &eax, &ebx, &ecx, &edx) == 0)
+ return VIRTUALIZATION_NONE;
- hypervisor = !!(ecx & 0x80000000U);
+ hypervisor = ecx & 0x80000000U;
if (hypervisor) {
union {
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)
- );
+ __cpuid(0x40000000U, eax, ebx, ecx, edx);
+
+ sig.sig32[0] = ebx;
+ sig.sig32[1] = ecx;
+ sig.sig32[2] = edx;
log_debug("Virtualization found, CPUID=%s", sig.text);
return r;
}
-
-
for (j = 0; j < ELEMENTSOF(dmi_vendor_table); j++)
if (startswith(s, dmi_vendor_table[j].vendor)) {
log_debug("Virtualization %s found in DMI (%s)", s, dmi_vendors[i]);
}
static int detect_vm_xen(void) {
+
/* Check for Dom0 will be executed later in detect_vm_xen_dom0
- Thats why we dont check the content of /proc/xen/capabilities here. */
- if (access("/proc/xen/capabilities", F_OK) < 0) {
- log_debug("Virtualization XEN not found, /proc/xen/capabilities does not exist");
+ The presence of /proc/xen indicates some form of a Xen domain */
+ if (access("/proc/xen", F_OK) < 0) {
+ log_debug("Virtualization XEN not found, /proc/xen does not exist");
return VIRTUALIZATION_NONE;
}
- log_debug("Virtualization XEN found (/proc/xen/capabilities exists)");
- return VIRTUALIZATION_XEN;
-
+ log_debug("Virtualization XEN found (/proc/xen exists)");
+ return VIRTUALIZATION_XEN;
}
-static bool detect_vm_xen_dom0(void) {
+#define XENFEAT_dom0 11 /* xen/include/public/features.h */
+#define PATH_FEATURES "/sys/hypervisor/properties/features"
+/* Returns -errno, or 0 for domU, or 1 for dom0 */
+static int detect_vm_xen_dom0(void) {
_cleanup_free_ char *domcap = NULL;
char *cap, *i;
int r;
+ r = read_one_line_file(PATH_FEATURES, &domcap);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ if (r == 0) {
+ unsigned long features;
+
+ /* Here, we need to use sscanf() instead of safe_atoul()
+ * as the string lacks the leading "0x". */
+ r = sscanf(domcap, "%lx", &features);
+ if (r == 1) {
+ r = !!(features & (1U << XENFEAT_dom0));
+ log_debug("Virtualization XEN, found %s with value %08lx, "
+ "XENFEAT_dom0 (indicating the 'hardware domain') is%s set.",
+ PATH_FEATURES, features, r ? "" : " not");
+ return r;
+ }
+ log_debug("Virtualization XEN, found %s, unhandled content '%s'",
+ PATH_FEATURES, domcap);
+ }
+
r = read_one_line_file("/proc/xen/capabilities", &domcap);
if (r == -ENOENT) {
- log_debug("Virtualization XEN not found, /proc/xen/capabilities does not exist");
- return false;
+ log_debug("Virtualization XEN because /proc/xen/capabilities does not exist");
+ return 0;
}
if (r < 0)
return r;
break;
if (!cap) {
log_debug("Virtualization XEN DomU found (/proc/xen/capabilites)");
- return false;
+ return 0;
}
log_debug("Virtualization XEN Dom0 ignored (/proc/xen/capabilities)");
- return true;
+ return 1;
}
static int detect_vm_hypervisor(void) {
/* Detect User-Mode Linux by reading /proc/cpuinfo */
r = read_full_file("/proc/cpuinfo", &cpuinfo_contents, NULL);
+ if (r == -ENOENT) {
+ log_debug("/proc/cpuinfo not found, assuming no UML virtualization.");
+ return VIRTUALIZATION_NONE;
+ }
if (r < 0)
return r;
return VIRTUALIZATION_UML;
}
- log_debug("No virtualization found in /proc/cpuinfo.");
+ log_debug("UML virtualization not found in /proc/cpuinfo.");
return VIRTUALIZATION_NONE;
}
/* Returns a short identifier for the various VM implementations */
int detect_vm(void) {
static thread_local int cached_found = _VIRTUALIZATION_INVALID;
- int r;
+ bool other = false;
+ int r, dmi;
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)
+ * → First, try to detect Oracle Virtualbox, even if it uses KVM, as well as Xen even if it cloaks as Microsoft
+ * Hyper-V.
+ *
+ * → Second, try to detect from CPUID, this will report KVM for whatever software is used even if info in DMI is
+ * overwritten.
+ *
+ * → Third, try to detect from DMI. */
+
+ dmi = detect_vm_dmi();
+ if (IN_SET(dmi, VIRTUALIZATION_ORACLE, VIRTUALIZATION_XEN)) {
+ r = dmi;
goto finish;
+ }
r = detect_vm_cpuid();
if (r < 0)
return r;
- if (r != VIRTUALIZATION_NONE)
+ if (r == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (r != VIRTUALIZATION_NONE)
+ goto finish;
+
+ /* Now, let's get back to DMI */
+ if (dmi < 0)
+ return dmi;
+ if (dmi == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (dmi != VIRTUALIZATION_NONE) {
+ r = dmi;
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 */
+ * because we're not an x86 guest), then we should try the /proc/xen
+ * directory next. If that's not found, then we check for the high-level
+ * hypervisor sysfs file.
+ */
r = detect_vm_xen();
if (r < 0)
return r;
- if (r != VIRTUALIZATION_NONE)
+ if (r == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (r != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_hypervisor();
if (r < 0)
return r;
- if (r != VIRTUALIZATION_NONE)
+ if (r == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (r != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_device_tree();
if (r < 0)
return r;
- if (r != VIRTUALIZATION_NONE)
+ if (r == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (r != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_uml();
if (r < 0)
return r;
- if (r != VIRTUALIZATION_NONE)
+ if (r == VIRTUALIZATION_VM_OTHER)
+ other = true;
+ else if (r != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_zvm();
/* x86 xen Dom0 is detected as XEN in hypervisor and maybe others.
* In order to detect the Dom0 as not virtualization we need to
* double-check it */
- if (r == VIRTUALIZATION_XEN && detect_vm_xen_dom0())
- r = VIRTUALIZATION_NONE;
+ if (r == VIRTUALIZATION_XEN) {
+ int dom0;
+
+ dom0 = detect_vm_xen_dom0();
+ if (dom0 < 0)
+ return dom0;
+ if (dom0 > 0)
+ r = VIRTUALIZATION_NONE;
+ } else if (r == VIRTUALIZATION_NONE && other)
+ r = VIRTUALIZATION_VM_OTHER;
cached_found = r;
log_debug("Found VM virtualization %s", virtualization_to_string(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. */
+ /* /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 */
+ if (getpid_cached() == 1) {
+ /* If we are PID 1 we can just check our own environment variable, and that's authoritative. */
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;
+ goto translate_name;
+ }
+
+ /* Otherwise, PID 1 might have 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 >= 0) {
+ e = m;
+ goto translate_name;
+ }
+ if (r != -ENOENT)
+ return log_debug_errno(r, "Failed to read /run/systemd/container: %m");
+
+ /* 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) {
e = m;
+ goto translate_name;
}
+ if (r < 0) /* This only works if we have CAP_SYS_PTRACE, hence let's better ignore failures here */
+ log_debug_errno(r, "Failed to read $container of PID 1, ignoring: %m");
+
+ /* Interestingly /proc/1/sched actually shows the host's PID for what we see as PID 1. Hence, if the PID shown
+ * there is not 1, we know we are in a PID namespace. and hence a container. */
+ r = read_one_line_file("/proc/1/sched", &m);
+ if (r >= 0) {
+ const char *t;
+ t = strrchr(m, '(');
+ if (!t)
+ return -EIO;
+
+ if (!startswith(t, "(1,")) {
+ r = VIRTUALIZATION_CONTAINER_OTHER;
+ goto finish;
+ }
+ } else if (r != -ENOENT)
+ return r;
+
+ /* If that didn't work, give up, assume no container manager. */
+ r = VIRTUALIZATION_NONE;
+ goto finish;
+
+translate_name:
for (j = 0; j < ELEMENTSOF(value_table); j++)
if (streq(e, value_table[j].value)) {
r = value_table[j].id;
r = VIRTUALIZATION_CONTAINER_OTHER;
finish:
- log_debug("Found container virtualization %s", virtualization_to_string(r));
+ log_debug("Found container virtualization %s.", virtualization_to_string(r));
cached_found = r;
return r;
}
f = fopen(name, "re");
if (!f) {
log_debug_errno(errno, "Failed to open %s: %m", name);
- return errno == -ENOENT ? false : -errno;
+ return errno == ENOENT ? false : -errno;
}
n = getline(&buf, &n_allocated, f);
#endif // 0
int running_in_chroot(void) {
- int ret;
+ int r;
#if 0 /// elogind does not allow to ignore chroots, we are never init!
if (getenv_bool("SYSTEMD_IGNORE_CHROOT") > 0)
return 0;
#endif // 0
- ret = files_same("/proc/1/root", "/");
- if (ret < 0)
- return ret;
+ r = files_same("/proc/1/root", "/", 0);
+ if (r < 0)
+ return r;
- return ret == 0;
+ return r == 0;
}
static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
[VIRTUALIZATION_ZVM] = "zvm",
[VIRTUALIZATION_PARALLELS] = "parallels",
[VIRTUALIZATION_BHYVE] = "bhyve",
+ [VIRTUALIZATION_QNX] = "qnx",
[VIRTUALIZATION_VM_OTHER] = "vm-other",
[VIRTUALIZATION_SYSTEMD_NSPAWN] = "systemd-nspawn",