{ "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 */
+ /* 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 },
};
uint32_t eax, ecx;
{ "Xen", VIRTUALIZATION_XEN },
{ "Bochs", VIRTUALIZATION_BOCHS },
{ "Parallels", VIRTUALIZATION_PARALLELS },
+ /* https://wiki.freebsd.org/bhyve */
+ { "BHYVE", VIRTUALIZATION_BHYVE },
};
unsigned i;
int r;
/* Returns a short identifier for the various VM implementations */
int detect_vm(void) {
static thread_local int cached_found = _VIRTUALIZATION_INVALID;
- int r;
+ 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();
+ * -> First try to detect Oracle Virtualbox, even if it uses KVM.
+ * -> 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 (dmi == VIRTUALIZATION_ORACLE) {
+ r = dmi;
+ goto finish;
+ }
+
+ r = detect_vm_cpuid();
if (r < 0)
return r;
if (r != VIRTUALIZATION_NONE)
goto finish;
- r = detect_vm_cpuid();
+ r = dmi;
if (r < 0)
return r;
if (r != VIRTUALIZATION_NONE)
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;
}
if (getpid() == 1) {
- /* If we are PID 1 we can just check our own
- * environment variable */
+ /* 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;
}
return r;
}
+
+static int userns_has_mapping(const char *name) {
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_free_ char *buf = NULL;
+ size_t n_allocated = 0;
+ ssize_t n;
+ uint32_t a, b, c;
+ int r;
+
+ f = fopen(name, "re");
+ if (!f) {
+ log_debug_errno(errno, "Failed to open %s: %m", name);
+ return errno == ENOENT ? false : -errno;
+ }
+
+ n = getline(&buf, &n_allocated, f);
+ if (n < 0) {
+ if (feof(f)) {
+ log_debug("%s is empty, we're in an uninitialized user namespace", name);
+ return true;
+ }
+
+ return log_debug_errno(errno, "Failed to read %s: %m", name);
+ }
+
+ r = sscanf(buf, "%"PRIu32" %"PRIu32" %"PRIu32, &a, &b, &c);
+ if (r < 3)
+ return log_debug_errno(errno, "Failed to parse %s: %m", name);
+
+ if (a == 0 && b == 0 && c == UINT32_MAX) {
+ /* The kernel calls mappings_overlap() and does not allow overlaps */
+ log_debug("%s has a full 1:1 mapping", name);
+ return false;
+ }
+
+ /* Anything else implies that we are in a user namespace */
+ log_debug("Mapping found in %s, we're in a user namespace", name);
+ return true;
+}
+
+int running_in_userns(void) {
+ _cleanup_free_ char *line = NULL;
+ int r;
+
+ r = userns_has_mapping("/proc/self/uid_map");
+ if (r != 0)
+ return r;
+
+ r = userns_has_mapping("/proc/self/gid_map");
+ if (r != 0)
+ return r;
+
+ /* "setgroups" file was added in kernel v3.18-rc6-15-g9cc46516dd. It is also
+ * possible to compile a kernel without CONFIG_USER_NS, in which case "setgroups"
+ * also does not exist. We cannot distinguish those two cases, so assume that
+ * we're running on a stripped-down recent kernel, rather than on an old one,
+ * and if the file is not found, return false.
+ */
+ r = read_one_line_file("/proc/self/setgroups", &line);
+ if (r < 0) {
+ log_debug_errno(r, "/proc/self/setgroups: %m");
+ return r == -ENOENT ? false : r;
+ }
+
+ truncate_nl(line);
+ r = streq(line, "deny");
+ /* See user_namespaces(7) for a description of this "setgroups" contents. */
+ log_debug("/proc/self/setgroups contains \"%s\", %s user namespace", line, r ? "in" : "not in");
+ return r;
+}
#endif // 0
int running_in_chroot(void) {
- int ret;
+ _cleanup_free_ char *self_mnt = NULL, *pid1_mnt = NULL;
+ int r;
+
+ /* Try to detect whether we are running in a chroot() environment. Specifically, check whether we have a
+ * different root directory than PID 1, even though we live in the same mount namespace as it. */
+
+#if 0 /// elogind does not allow to ignore chroots, we are never init!
+ if (getenv_bool("SYSTEMD_IGNORE_CHROOT") > 0)
+ return 0;
+#endif // 0
+
+ r = files_same("/proc/1/root", "/");
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 0;
- ret = files_same("/proc/1/root", "/");
- if (ret < 0)
- return ret;
+ r = readlink_malloc("/proc/self/ns/mnt", &self_mnt);
+ if (r < 0)
+ return r;
+
+ r = readlink_malloc("/proc/1/ns/mnt", &pid1_mnt);
+ if (r < 0)
+ return r;
- return ret == 0;
+ return streq(self_mnt, pid1_mnt); /* Only if we live in the same namespace! */
}
static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
[VIRTUALIZATION_MICROSOFT] = "microsoft",
[VIRTUALIZATION_ZVM] = "zvm",
[VIRTUALIZATION_PARALLELS] = "parallels",
+ [VIRTUALIZATION_BHYVE] = "bhyve",
[VIRTUALIZATION_VM_OTHER] = "vm-other",
[VIRTUALIZATION_SYSTEMD_NSPAWN] = "systemd-nspawn",
~ianmdlvl / elogind.git / blobdiff