/*** 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) ); log_debug("Virtualization found, CPUID=%s", sig.text); 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 log_debug("No virtualization found in CPUID"); 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) { log_debug_errno(errno, "/proc/device-tree: %m"); return VIRTUALIZATION_NONE; } return -errno; } FOREACH_DIRENT(dent, dir, return -errno) if (strstr(dent->d_name, "fw-cfg")) { log_debug("Virtualization QEMU: \"fw-cfg\" present in /proc/device-tree/%s", dent->d_name); return VIRTUALIZATION_QEMU; } log_debug("No virtualization found in /proc/device-tree/*"); return VIRTUALIZATION_NONE; } else if (r < 0) return r; log_debug("Virtualization %s found in /proc/device-tree/hypervisor/compatible", hvtype); if (streq(hvtype, "linux,kvm")) return VIRTUALIZATION_KVM; else if (strstr(hvtype, "xen")) return VIRTUALIZATION_XEN; else return VIRTUALIZATION_VM_OTHER; #else log_debug("This platform does not support /proc/device-tree"); 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)) { log_debug("Virtualization %s found in DMI (%s)", s, dmi_vendors[i]); return dmi_vendor_table[j].id; } } #endif log_debug("No virtualization found in DMI"); return VIRTUALIZATION_NONE; } 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"); return VIRTUALIZATION_NONE; } log_debug("Virtualization XEN found (/proc/xen/capabilities exists)"); return VIRTUALIZATION_XEN; } static bool detect_vm_xen_dom0(void) { _cleanup_free_ char *domcap = NULL; char *cap, *i; int r; 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; } if (r < 0) return r; i = domcap; while ((cap = strsep(&i, ","))) if (streq(cap, "control_d")) break; if (!cap) { log_debug("Virtualization XEN DomU found (/proc/xen/capabilites)"); return false; } log_debug("Virtualization XEN Dom0 ignored (/proc/xen/capabilities)"); return true; } 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; log_debug("Virtualization %s found in /sys/hypervisor/type", hvtype); 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")) { log_debug("UML virtualization found in /proc/cpuinfo"); return VIRTUALIZATION_UML; } log_debug("No virtualization found in /proc/cpuinfo."); 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; log_debug("Virtualization %s found in /proc/sysinfo", t); if (streq(t, "z/VM")) return VIRTUALIZATION_ZVM; else return VIRTUALIZATION_KVM; #else log_debug("This platform does not support /proc/sysinfo"); 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: /* 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; cached_found = r; log_debug("Found VM virtualization %s", virtualization_to_string(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: log_debug("Found container virtualization %s", virtualization_to_string(r)); cached_found = r; return r; } int detect_virtualization(void) { int r; r = detect_container(); if (r == 0) r = detect_vm(); return r; } 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);