X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fbasic%2Fvirt.c;h=35beebe7fa4116f5dedfd2b2a0e50fd0cc97486c;hp=8e398e506f924403ae8629697f70d94ae2b93405;hb=2a4a438b7c7306da5f698d2247e646263f3c45c0;hpb=d2338db3145922b1dfcb3b458e5bce2568a9347a
diff --git a/src/basic/virt.c b/src/basic/virt.c
index 8e398e506..35beebe7f 100644
--- a/src/basic/virt.c
+++ b/src/basic/virt.c
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
/***
This file is part of systemd.
@@ -19,18 +17,27 @@
along with systemd; If not, see .
***/
-#include
#include
+#include
+#include
+#include
#include
-#include "util.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"
-#include "fileio.h"
+#if 0 /// UNNEEDED by elogind
static int detect_vm_cpuid(void) {
- /* Both CPUID and DMI are x86 specific interfaces... */
+ /* CPUID is an x86 specific interface. */
#if defined(__i386__) || defined(__x86_64__)
static const struct {
@@ -43,6 +50,8 @@ static int detect_vm_cpuid(void) {
{ "VMwareVMware", VIRTUALIZATION_VMWARE },
/* http://msdn.microsoft.com/en-us/library/ff542428.aspx */
{ "Microsoft Hv", VIRTUALIZATION_MICROSOFT },
+ /* https://wiki.freebsd.org/bhyve */
+ { "bhyve bhyve ", VIRTUALIZATION_BHYVE },
};
uint32_t eax, ecx;
@@ -92,6 +101,8 @@ static int detect_vm_cpuid(void) {
: "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;
@@ -99,6 +110,7 @@ static int detect_vm_cpuid(void) {
return VIRTUALIZATION_VM_OTHER;
}
#endif
+ log_debug("No virtualization found in CPUID");
return VIRTUALIZATION_NONE;
}
@@ -115,19 +127,25 @@ static int detect_vm_device_tree(void) {
dir = opendir("/proc/device-tree");
if (!dir) {
- if (errno == ENOENT)
+ 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"))
+ 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"))
@@ -135,16 +153,16 @@ static int detect_vm_device_tree(void) {
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) {
-
- /* Both CPUID and DMI are x86 specific interfaces... */
-#if defined(__i386__) || defined(__x86_64__)
+#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"
@@ -154,6 +172,7 @@ static int detect_vm_dmi(void) {
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 },
@@ -162,6 +181,8 @@ static int detect_vm_dmi(void) {
{ "Xen", VIRTUALIZATION_XEN },
{ "Bochs", VIRTUALIZATION_BOCHS },
{ "Parallels", VIRTUALIZATION_PARALLELS },
+ /* https://wiki.freebsd.org/bhyve */
+ { "BHYVE", VIRTUALIZATION_BHYVE },
};
unsigned i;
int r;
@@ -173,47 +194,77 @@ static int detect_vm_dmi(void) {
r = read_one_line_file(dmi_vendors[i], &s);
if (r < 0) {
if (r == -ENOENT)
- continue;
+ continue;
return r;
- }
+ }
+
+
for (j = 0; j < ELEMENTSOF(dmi_vendor_table); j++)
- if (startswith(s, dmi_vendor_table[j].vendor))
+ 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)
- return VIRTUALIZATION_NONE;
+ 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;
+ while ((cap = strsep(&i, ",")))
+ if (streq(cap, "control_d"))
+ break;
+ if (!cap) {
+ log_debug("Virtualization XEN DomU found (/proc/xen/capabilites)");
+ return false;
+ }
- return cap ? VIRTUALIZATION_NONE : VIRTUALIZATION_XEN;
- }
+ log_debug("Virtualization XEN Dom0 ignored (/proc/xen/capabilities)");
+ return true;
+}
static int detect_vm_hypervisor(void) {
- _cleanup_free_ char *hvtype = NULL;
+ _cleanup_free_ char *hvtype = NULL;
int r;
- r = read_one_line_file("/sys/hypervisor/type", &hvtype);
+ 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
@@ -228,9 +279,13 @@ static int detect_vm_uml(void) {
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"))
+
+ 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;
}
@@ -246,14 +301,16 @@ static int detect_vm_zvm(void) {
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) {
@@ -263,24 +320,33 @@ int detect_vm(void) {
if (cached_found >= 0)
return cached_found;
- /* Try xen capabilities file first, if not found try
- * high-level hypervisor sysfs file:
+ /* 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.
*
- * https://bugs.freedesktop.org/show_bug.cgi?id=77271 */
-
- r = detect_vm_xen();
+ * 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_dmi();
+ r = detect_vm_cpuid();
if (r < 0)
return r;
if (r != VIRTUALIZATION_NONE)
goto finish;
- r = detect_vm_cpuid();
+ /* 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)
@@ -302,16 +368,24 @@ int detect_vm(void) {
if (r < 0)
return r;
if (r != VIRTUALIZATION_NONE)
- goto finish;
+ 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;
}
+#endif // 0
int detect_container(void) {
@@ -323,6 +397,7 @@ int detect_container(void) {
{ "lxc-libvirt", VIRTUALIZATION_LXC_LIBVIRT },
{ "systemd-nspawn", VIRTUALIZATION_SYSTEMD_NSPAWN },
{ "docker", VIRTUALIZATION_DOCKER },
+ { "rkt", VIRTUALIZATION_RKT },
};
static thread_local int cached_found = _VIRTUALIZATION_INVALID;
@@ -393,26 +468,111 @@ int detect_container(void) {
goto finish;
}
- r = VIRTUALIZATION_NONE;
+ r = VIRTUALIZATION_CONTAINER_OTHER;
finish:
+ log_debug("Found container virtualization %s", virtualization_to_string(r));
cached_found = r;
return r;
}
-/// UNNEEDED by elogind
-#if 0
+#if 0 /// UNNEEDED by elogind
int detect_virtualization(void) {
int r;
r = detect_container();
+ if (r == 0)
+ r = detect_vm();
+
+ 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;
- return detect_vm();
+ /* "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;
+
+#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;
+
+ return ret == 0;
+}
+
static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
[VIRTUALIZATION_NONE] = "none",
[VIRTUALIZATION_KVM] = "kvm",
@@ -425,6 +585,7 @@ 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",
@@ -432,6 +593,7 @@ static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
[VIRTUALIZATION_LXC] = "lxc",
[VIRTUALIZATION_OPENVZ] = "openvz",
[VIRTUALIZATION_DOCKER] = "docker",
+ [VIRTUALIZATION_RKT] = "rkt",
[VIRTUALIZATION_CONTAINER_OTHER] = "container-other",
};