fwupd/plugins/pci-mei/fu-plugin-pci-mei.c
Richard Hughes 0f6d754d5a Detect if the MEI device has known security issues
If it has, fail HSI-1.
2020-06-01 22:49:39 +01:00

247 lines
7.2 KiB
C

/*
* Copyright (C) 2020 Richard Hughes <richard@hughsie.com>
*
* SPDX-License-Identifier: LGPL-2.1+
*/
#include "config.h"
#include "fu-plugin-vfuncs.h"
#include "fu-hash.h"
#include "fu-mei-common.h"
struct FuPluginData {
gboolean has_device;
guint32 mei_cfg;
FuMeiVersion vers;
FuMeiIssue issue;
};
#define PCI_CFG_HFS_1 0x40
void
fu_plugin_init (FuPlugin *plugin)
{
fu_plugin_alloc_data (plugin, sizeof (FuPluginData));
fu_plugin_set_build_hash (plugin, FU_BUILD_HASH);
fu_plugin_add_udev_subsystem (plugin, "pci");
}
static FuMeiFamily
fu_mei_detect_family (FuPlugin *plugin)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
guint8 operating_mode = (priv->mei_cfg >> 16) & 0xF;
guint8 ver = priv->vers.major;
if (ver == 1 || ver == 2) {
if (operating_mode == 0xF)
return FU_MEI_FAMILY_SPS;
return FU_MEI_FAMILY_TXE;
}
if (ver == 3 || ver == 4 || ver == 5)
return FU_MEI_FAMILY_TXE;
if (ver == 6 || ver == 7 || ver == 8 || ver == 9 || ver == 10)
return FU_MEI_FAMILY_ME;
if (ver == 11 || ver == 12 || ver == 13 || ver == 14 || ver == 15)
return FU_MEI_FAMILY_CSME;
return FU_MEI_FAMILY_UNKNOWN;
}
static gboolean
fu_mei_parse_fwvers (FuPlugin *plugin, const gchar *fwvers, GError **error)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
FuMeiFamily family;
g_auto(GStrv) lines = NULL;
g_auto(GStrv) sections = NULL;
g_auto(GStrv) split = NULL;
/* we only care about the first version */
lines = g_strsplit (fwvers, "\n", -1);
if (g_strv_length (lines) < 1) {
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_DATA,
"expected data, got %s", fwvers);
return FALSE;
}
/* split platform : version */
sections = g_strsplit (lines[0], ":", -1);
if (g_strv_length (sections) != 2) {
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_DATA,
"expected platform:major.minor.micro.build, got %s",
lines[0]);
return FALSE;
}
/* parse platform and versions */
priv->vers.platform = fu_common_strtoull (sections[0]);
split = g_strsplit (sections[1], ".", -1);
if (g_strv_length (split) != 4) {
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_DATA,
"expected major.minor.micro.build, got %s",
sections[1]);
return FALSE;
}
priv->vers.major = fu_common_strtoull (split[0]);
priv->vers.minor = fu_common_strtoull (split[1]);
priv->vers.hotfix = fu_common_strtoull (split[2]);
priv->vers.buildno = fu_common_strtoull (split[3]);
/* check the AMT version for issues using the data from:
* https://downloadcenter.intel.com/download/28632 */
family = fu_mei_detect_family (plugin);
if (family == FU_MEI_FAMILY_CSME)
priv->issue = fu_mei_common_is_csme_vulnerable (&priv->vers);
else if (family == FU_MEI_FAMILY_TXE)
priv->issue = fu_mei_common_is_txe_vulnerable (&priv->vers);
else if (family == FU_MEI_FAMILY_SPS)
priv->issue = fu_mei_common_is_sps_vulnerable (&priv->vers);
if (g_getenv ("FWUPD_MEI_VERBOSE") != NULL) {
g_debug ("%s version parsed as %u.%u.%u",
fu_mei_common_family_to_string (family),
priv->vers.major, priv->vers.minor, priv->vers.hotfix);
}
return TRUE;
}
gboolean
fu_plugin_udev_device_added (FuPlugin *plugin, FuUdevDevice *device, GError **error)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
const gchar *fwvers;
guint8 buf[4] = { 0x0 };
g_autoptr(FuDeviceLocker) locker = NULL;
/* interesting device? */
if (g_strcmp0 (fu_udev_device_get_subsystem (device), "pci") != 0)
return TRUE;
/* open the config */
fu_udev_device_set_flags (device, FU_UDEV_DEVICE_FLAG_USE_CONFIG);
if (!fu_udev_device_set_physical_id (device, "pci", error))
return FALSE;
locker = fu_device_locker_new (device, error);
if (locker == NULL)
return FALSE;
/* grab MEI config Register */
if (!fu_udev_device_pread_full (device, PCI_CFG_HFS_1, buf, sizeof(buf), error)) {
g_prefix_error (error, "could not read MEI: ");
return FALSE;
}
priv->mei_cfg = fu_common_read_uint32 (buf, G_LITTLE_ENDIAN);
priv->has_device = TRUE;
/* check firmware version */
fwvers = fu_udev_device_get_sysfs_attr (device, "mei/mei0/fw_ver", NULL);
if (fwvers != NULL) {
if (!fu_mei_parse_fwvers (plugin, fwvers, error))
return FALSE;
}
/* success */
return TRUE;
}
static void
fu_plugin_add_security_attrs_manufacturing_mode (FuPlugin *plugin, FuSecurityAttrs *attrs)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
g_autoptr(FwupdSecurityAttr) attr = NULL;
/* create attr */
attr = fwupd_security_attr_new (FWUPD_SECURITY_ATTR_ID_MEI_MANUFACTURING_MODE);
fwupd_security_attr_set_plugin (attr, fu_plugin_get_name (plugin));
fwupd_security_attr_set_level (attr, FWUPD_SECURITY_ATTR_LEVEL_CRITICAL);
fu_security_attrs_append (attrs, attr);
/* Manufacturing Mode */
if (((priv->mei_cfg >> 4) & 0x1) != 0) {
fwupd_security_attr_set_result (attr, FWUPD_SECURITY_ATTR_RESULT_NOT_LOCKED);
return;
}
/* success */
fwupd_security_attr_add_flag (attr, FWUPD_SECURITY_ATTR_FLAG_SUCCESS);
fwupd_security_attr_set_result (attr, FWUPD_SECURITY_ATTR_RESULT_LOCKED);
}
static void
fu_plugin_add_security_attrs_override_strap (FuPlugin *plugin, FuSecurityAttrs *attrs)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
g_autoptr(FwupdSecurityAttr) attr = NULL;
/* create attr */
attr = fwupd_security_attr_new (FWUPD_SECURITY_ATTR_ID_MEI_OVERRIDE_STRAP);
fwupd_security_attr_set_plugin (attr, fu_plugin_get_name (plugin));
fwupd_security_attr_set_level (attr, FWUPD_SECURITY_ATTR_LEVEL_CRITICAL);
fu_security_attrs_append (attrs, attr);
/* Flash Descriptor Security Override Strap */
if (((priv->mei_cfg >> 16) & 0x7) != 0) {
fwupd_security_attr_set_result (attr, FWUPD_SECURITY_ATTR_RESULT_NOT_LOCKED);
return;
}
/* success */
fwupd_security_attr_add_flag (attr, FWUPD_SECURITY_ATTR_FLAG_SUCCESS);
fwupd_security_attr_set_result (attr, FWUPD_SECURITY_ATTR_RESULT_LOCKED);
}
static void
fu_plugin_add_security_attrs_csme_version (FuPlugin *plugin, FuSecurityAttrs *attrs)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
g_autoptr(FwupdSecurityAttr) attr = NULL;
if (priv->issue == FU_MEI_ISSUE_UNKNOWN) {
g_warning ("ME family not supported for %u:%u.%u.%u.%u",
priv->vers.platform,
priv->vers.major,
priv->vers.minor,
priv->vers.hotfix,
priv->vers.buildno);
return;
}
/* create attr */
attr = fwupd_security_attr_new (FWUPD_SECURITY_ATTR_ID_MEI_VERSION);
fwupd_security_attr_set_plugin (attr, fu_plugin_get_name (plugin));
fwupd_security_attr_set_level (attr, FWUPD_SECURITY_ATTR_LEVEL_CRITICAL);
fu_security_attrs_append (attrs, attr);
/* Flash Descriptor Security Override Strap */
if (priv->issue == FU_MEI_ISSUE_VULNERABLE) {
fwupd_security_attr_set_result (attr, FWUPD_SECURITY_ATTR_RESULT_NOT_VALID);
return;
}
/* success */
fwupd_security_attr_add_flag (attr, FWUPD_SECURITY_ATTR_FLAG_SUCCESS);
}
void
fu_plugin_add_security_attrs (FuPlugin *plugin, FuSecurityAttrs *attrs)
{
FuPluginData *priv = fu_plugin_get_data (plugin);
/* only Intel */
if (!fu_common_is_cpu_intel ())
return;
if (!priv->has_device)
return;
fu_plugin_add_security_attrs_manufacturing_mode (plugin, attrs);
fu_plugin_add_security_attrs_override_strap (plugin, attrs);
fu_plugin_add_security_attrs_csme_version (plugin, attrs);
}