Merge pull request #2587 from haraldh/tpmv3

sd-boot: put hashed kernel command line in a PCR of the TPM

6 files changed, 386 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index 3b7cc1e33e..9f051e2954 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2701,6 +2701,7 @@ systemd_boot_headers = \
 	src/boot/efi/console.h \
 	src/boot/efi/graphics.h \
 	src/boot/efi/pefile.h \
+	src/boot/efi/measure.h \
 	src/boot/efi/disk.h
 
 systemd_boot_sources = \
@@ -2709,6 +2710,7 @@ systemd_boot_sources = \
 	src/boot/efi/graphics.c \
 	src/boot/efi/pefile.c \
 	src/boot/efi/disk.c \
+	src/boot/efi/measure.c \
 	src/boot/efi/boot.c
 
 EXTRA_DIST += $(systemd_boot_sources) $(systemd_boot_headers)
@@ -2745,6 +2747,7 @@ stub_headers = \
 	src/boot/efi/disk.h \
 	src/boot/efi/graphics.h \
 	src/boot/efi/splash.h \
+	src/boot/efi/measure.h \
 	src/boot/efi/linux.h
 
 stub_sources = \
@@ -2754,6 +2757,7 @@ stub_sources = \
 	src/boot/efi/graphics.c \
 	src/boot/efi/splash.c \
 	src/boot/efi/linux.c \
+	src/boot/efi/measure.c \
 	src/boot/efi/stub.c
 
 EXTRA_DIST += \
diff --git a/configure.ac b/configure.ac
index 5fd73c59f1..59cc9fd99e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1218,6 +1218,28 @@ AS_IF([test "x$enable_gnuefi" != "xno"], [
 AM_CONDITIONAL(HAVE_GNUEFI, [test "x$have_gnuefi" = xyes])
 
 # ------------------------------------------------------------------------------
+have_tpm=no
+AC_ARG_ENABLE([tpm], AS_HELP_STRING([--enable-tpm],[Enable optional TPM support]),
+                [case "${enableval}" in
+                        yes) have_tpm=yes ;;
+                        no) have_tpm=no ;;
+                        *) AC_MSG_ERROR(bad value ${enableval} for --enable-tpm) ;;
+                esac],
+                [have_tpm=no])
+
+if test "x${have_tpm}" != xno ; then
+        AC_DEFINE(SD_BOOT_LOG_TPM, 1, [Define if TPM should be used to log events and extend the registers])
+fi
+
+AC_ARG_WITH(tpm-pcrindex,
+        AS_HELP_STRING([--with-tpm-pcrindex=<NUM>],
+                [TPM PCR register number to use]),
+        [SD_TPM_PCR="$withval"],
+        [SD_TPM_PCR="8"])
+
+AC_DEFINE_UNQUOTED(SD_TPM_PCR, [$SD_TPM_PCR], [TPM PCR register number to use])
+
+# ------------------------------------------------------------------------------
 have_kdbus=no
 AC_ARG_ENABLE(kdbus, AS_HELP_STRING([--disable-kdbus], [do not connect to kdbus by default]))
 if test "x$enable_kdbus" != "xno"; then
@@ -1571,6 +1593,7 @@ AC_MSG_RESULT([
         dbus:                    ${have_dbus}
         nss-myhostname:          ${have_myhostname}
         hwdb:                    ${enable_hwdb}
+        tpm:                     ${have_tpm}
         kdbus:                   ${have_kdbus}
         Python:                  ${have_python}
         man pages:               ${have_manpages}
diff --git a/src/boot/efi/boot.c b/src/boot/efi/boot.c
index 893980071f..30c1ead1aa 100644
--- a/src/boot/efi/boot.c
+++ b/src/boot/efi/boot.c
@@ -22,6 +22,7 @@
 #include "linux.h"
 #include "pefile.h"
 #include "util.h"
+#include "measure.h"
 
 #ifndef EFI_OS_INDICATIONS_BOOT_TO_FW_UI
 #define EFI_OS_INDICATIONS_BOOT_TO_FW_UI 0x0000000000000001ULL
@@ -1644,6 +1645,18 @@ static EFI_STATUS image_start(EFI_HANDLE parent_image, const Config *config, con
                 }
                 loaded_image->LoadOptions = options;
                 loaded_image->LoadOptionsSize = (StrLen(loaded_image->LoadOptions)+1) * sizeof(CHAR16);
+
+#ifdef SD_BOOT_LOG_TPM
+                /* Try to log any options to the TPM, escpecially to catch manually edited options */
+                err = tpm_log_event(SD_TPM_PCR,
+                                    (EFI_PHYSICAL_ADDRESS) loaded_image->LoadOptions,
+                                    loaded_image->LoadOptionsSize, loaded_image->LoadOptions);
+                if (EFI_ERROR(err)) {
+                        Print(L"Unable to add image options measurement: %r", err);
+                        uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
+                        return err;
+                }
+#endif
         }
 
         efivar_set_time_usec(L"LoaderTimeExecUSec", 0);
diff --git a/src/boot/efi/measure.c b/src/boot/efi/measure.c
new file mode 100644
index 0000000000..7c016387c1
--- /dev/null
+++ b/src/boot/efi/measure.c
@@ -0,0 +1,312 @@
+/*
+ * This program 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.
+ *
+ * This program 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.
+ *
+ */
+
+#ifdef SD_BOOT_LOG_TPM
+
+#include <efi.h>
+#include <efilib.h>
+#include "measure.h"
+
+#define EFI_TCG_PROTOCOL_GUID { 0xf541796d, 0xa62e, 0x4954, {0xa7, 0x75, 0x95, 0x84, 0xf6, 0x1b, 0x9c, 0xdd} }
+
+typedef struct _TCG_VERSION {
+        UINT8 Major;
+        UINT8 Minor;
+        UINT8 RevMajor;
+        UINT8 RevMinor;
+} TCG_VERSION;
+
+typedef struct _TCG_BOOT_SERVICE_CAPABILITY {
+        UINT8 Size;
+        struct _TCG_VERSION StructureVersion;
+        struct _TCG_VERSION ProtocolSpecVersion;
+        UINT8 HashAlgorithmBitmap;
+        BOOLEAN TPMPresentFlag;
+        BOOLEAN TPMDeactivatedFlag;
+} TCG_BOOT_SERVICE_CAPABILITY;
+
+typedef UINT32 TCG_ALGORITHM_ID;
+#define TCG_ALG_SHA 0x00000004  // The SHA1 algorithm
+
+#define SHA1_DIGEST_SIZE 20
+
+typedef struct _TCG_DIGEST {
+        UINT8 Digest[SHA1_DIGEST_SIZE];
+} TCG_DIGEST;
+
+#define EV_IPL 13
+
+typedef struct _TCG_PCR_EVENT {
+        UINT32 PCRIndex;
+        UINT32 EventType;
+        struct _TCG_DIGEST digest;
+        UINT32 EventSize;
+        UINT8 Event[1];
+} TCG_PCR_EVENT;
+
+INTERFACE_DECL(_EFI_TCG);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG_STATUS_CHECK) (IN struct _EFI_TCG * This,
+                                                   OUT struct _TCG_BOOT_SERVICE_CAPABILITY * ProtocolCapability,
+                                                   OUT UINT32 * TCGFeatureFlags,
+                                                   OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
+                                                   OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_ALL) (IN struct _EFI_TCG * This,
+                                               IN UINT8 * HashData,
+                                               IN UINT64 HashDataLen,
+                                               IN TCG_ALGORITHM_ID AlgorithmId,
+                                               IN OUT UINT64 * HashedDataLen, IN OUT UINT8 ** HashedDataResult);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG_LOG_EVENT) (IN struct _EFI_TCG * This,
+                                                IN struct _TCG_PCR_EVENT * TCGLogData,
+                                                IN OUT UINT32 * EventNumber, IN UINT32 Flags);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG_PASS_THROUGH_TO_TPM) (IN struct _EFI_TCG * This,
+                                                          IN UINT32 TpmInputParameterBlockSize,
+                                                          IN UINT8 * TpmInputParameterBlock,
+                                                          IN UINT32 TpmOutputParameterBlockSize,
+                                                          IN UINT8 * TpmOutputParameterBlock);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_LOG_EXTEND_EVENT) (IN struct _EFI_TCG * This,
+                                                            IN EFI_PHYSICAL_ADDRESS HashData,
+                                                            IN UINT64 HashDataLen,
+                                                            IN TCG_ALGORITHM_ID AlgorithmId,
+                                                            IN struct _TCG_PCR_EVENT * TCGLogData,
+                                                            IN OUT UINT32 * EventNumber,
+                                                            OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);
+
+typedef struct _EFI_TCG {
+        EFI_TCG_STATUS_CHECK StatusCheck;
+        EFI_TCG_HASH_ALL HashAll;
+        EFI_TCG_LOG_EVENT LogEvent;
+        EFI_TCG_PASS_THROUGH_TO_TPM PassThroughToTPM;
+        EFI_TCG_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
+} EFI_TCG;
+
+#define EFI_TCG2_PROTOCOL_GUID {0x607f766c, 0x7455, 0x42be, { 0x93, 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f }}
+
+typedef struct tdEFI_TCG2_PROTOCOL EFI_TCG2_PROTOCOL;
+
+typedef struct tdEFI_TCG2_VERSION {
+        UINT8 Major;
+        UINT8 Minor;
+} EFI_TCG2_VERSION;
+
+typedef UINT32 EFI_TCG2_EVENT_LOG_BITMAP;
+typedef UINT32 EFI_TCG2_EVENT_LOG_FORMAT;
+typedef UINT32 EFI_TCG2_EVENT_ALGORITHM_BITMAP;
+
+#define EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2       0x00000001
+#define EFI_TCG2_EVENT_LOG_FORMAT_TCG_2         0x00000002
+
+typedef struct tdEFI_TCG2_BOOT_SERVICE_CAPABILITY {
+        UINT8 Size;
+        EFI_TCG2_VERSION StructureVersion;
+        EFI_TCG2_VERSION ProtocolVersion;
+        EFI_TCG2_EVENT_ALGORITHM_BITMAP HashAlgorithmBitmap;
+        EFI_TCG2_EVENT_LOG_BITMAP SupportedEventLogs;
+        BOOLEAN TPMPresentFlag;
+        UINT16 MaxCommandSize;
+        UINT16 MaxResponseSize;
+        UINT32 ManufacturerID;
+        UINT32 NumberOfPCRBanks;
+        EFI_TCG2_EVENT_ALGORITHM_BITMAP ActivePcrBanks;
+} EFI_TCG2_BOOT_SERVICE_CAPABILITY;
+
+#define EFI_TCG2_EVENT_HEADER_VERSION  1
+
+typedef struct {
+        UINT32 HeaderSize;
+        UINT16 HeaderVersion;
+        UINT32 PCRIndex;
+        UINT32 EventType;
+} EFI_TCG2_EVENT_HEADER;
+
+typedef struct tdEFI_TCG2_EVENT {
+        UINT32 Size;
+        EFI_TCG2_EVENT_HEADER Header;
+        UINT8 Event[1];
+} EFI_TCG2_EVENT;
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_CAPABILITY) (IN EFI_TCG2_PROTOCOL * This,
+                                                      IN OUT EFI_TCG2_BOOT_SERVICE_CAPABILITY * ProtocolCapability);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_EVENT_LOG) (IN EFI_TCG2_PROTOCOL * This,
+                                                     IN EFI_TCG2_EVENT_LOG_FORMAT EventLogFormat,
+                                                     OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
+                                                     OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry,
+                                                     OUT BOOLEAN * EventLogTruncated);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_HASH_LOG_EXTEND_EVENT) (IN EFI_TCG2_PROTOCOL * This,
+                                                             IN UINT64 Flags,
+                                                             IN EFI_PHYSICAL_ADDRESS DataToHash,
+                                                             IN UINT64 DataToHashLen, IN EFI_TCG2_EVENT * EfiTcgEvent);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_SUBMIT_COMMAND) (IN EFI_TCG2_PROTOCOL * This,
+                                                      IN UINT32 InputParameterBlockSize,
+                                                      IN UINT8 * InputParameterBlock,
+                                                      IN UINT32 OutputParameterBlockSize, IN UINT8 * OutputParameterBlock);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, OUT UINT32 * ActivePcrBanks);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, IN UINT32 ActivePcrBanks);
+
+typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This,
+                                                                          OUT UINT32 * OperationPresent, OUT UINT32 * Response);
+
+typedef struct tdEFI_TCG2_PROTOCOL {
+        EFI_TCG2_GET_CAPABILITY GetCapability;
+        EFI_TCG2_GET_EVENT_LOG GetEventLog;
+        EFI_TCG2_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
+        EFI_TCG2_SUBMIT_COMMAND SubmitCommand;
+        EFI_TCG2_GET_ACTIVE_PCR_BANKS GetActivePcrBanks;
+        EFI_TCG2_SET_ACTIVE_PCR_BANKS SetActivePcrBanks;
+        EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS GetResultOfSetActivePcrBanks;
+} EFI_TCG2;
+
+
+static EFI_STATUS tpm1_measure_to_pcr_and_event_log(const EFI_TCG *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
+                                                    UINTN buffer_size, const CHAR16 *description) {
+        EFI_STATUS status;
+        TCG_PCR_EVENT *tcg_event;
+        UINT32 event_number;
+        EFI_PHYSICAL_ADDRESS event_log_last;
+        UINTN desc_len;
+
+        desc_len = (StrLen(description) + 1) * sizeof(CHAR16);
+
+        tcg_event = AllocateZeroPool(desc_len + sizeof(TCG_PCR_EVENT));
+
+        if (tcg_event == NULL)
+                return EFI_OUT_OF_RESOURCES;
+
+        tcg_event->EventSize = desc_len;
+        CopyMem((VOID *) & tcg_event->Event[0], (VOID *) description, desc_len);
+
+        tcg_event->PCRIndex = pcrindex;
+        tcg_event->EventType = EV_IPL;
+
+        event_number = 1;
+        status = uefi_call_wrapper(tcg->HashLogExtendEvent, 7,
+                                   tcg, buffer, buffer_size, TCG_ALG_SHA, tcg_event, &event_number, &event_log_last);
+
+        if (EFI_ERROR(status))
+                return status;
+
+        uefi_call_wrapper(BS->FreePool, 1, tcg_event);
+
+        return EFI_SUCCESS;
+}
+
+
+static EFI_STATUS tpm2_measure_to_pcr_and_event_log(const EFI_TCG2 *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
+                                                    UINT64 buffer_size, const CHAR16 *description) {
+        EFI_STATUS status;
+        EFI_TCG2_EVENT *tcg_event;
+        UINTN desc_len;
+
+        desc_len = StrLen(description) * sizeof(CHAR16);
+
+        tcg_event = AllocateZeroPool(sizeof(*tcg_event) - sizeof(tcg_event->Event) + desc_len + 1);
+
+        if (tcg_event == NULL)
+                return EFI_OUT_OF_RESOURCES;
+
+        tcg_event->Size = sizeof(EFI_TCG2_EVENT) - sizeof(tcg_event->Event) + desc_len + 1;
+        tcg_event->Header.HeaderSize = sizeof(EFI_TCG2_EVENT_HEADER);
+        tcg_event->Header.HeaderVersion = EFI_TCG2_EVENT_HEADER_VERSION;
+        tcg_event->Header.PCRIndex = pcrindex;
+        tcg_event->Header.EventType = EV_IPL;
+
+        CopyMem((VOID *) tcg_event->Event, (VOID *) description, desc_len);
+
+        status = uefi_call_wrapper(tcg->HashLogExtendEvent, 5, tcg, 0, buffer, buffer_size, tcg_event);
+
+        uefi_call_wrapper(BS->FreePool, 1, tcg_event);
+
+        if (EFI_ERROR(status))
+                return status;
+
+        return EFI_SUCCESS;
+}
+
+static EFI_TCG * tcg1_interface_check(void) {
+        EFI_GUID tpm_guid = EFI_TCG_PROTOCOL_GUID;
+        EFI_STATUS status;
+        EFI_TCG *tcg;
+        TCG_BOOT_SERVICE_CAPABILITY capability;
+        UINT32 features;
+        EFI_PHYSICAL_ADDRESS event_log_location;
+        EFI_PHYSICAL_ADDRESS event_log_last_entry;
+
+        status = LibLocateProtocol(&tpm_guid, (void **) &tcg);
+
+        if (EFI_ERROR(status))
+                return NULL;
+
+        capability.Size = (UINT8) sizeof(capability);
+        status = uefi_call_wrapper(tcg->StatusCheck, 5, tcg, &capability, &features, &event_log_location, &event_log_last_entry);
+
+        if (EFI_ERROR(status))
+                return NULL;
+
+        if (capability.TPMDeactivatedFlag)
+                return NULL;
+
+        if (!capability.TPMPresentFlag)
+                return NULL;
+
+        return tcg;
+}
+
+static EFI_TCG2 * tcg2_interface_check(void) {
+        EFI_GUID tpm2_guid = EFI_TCG2_PROTOCOL_GUID;
+        EFI_STATUS status;
+        EFI_TCG2 *tcg;
+        EFI_TCG2_BOOT_SERVICE_CAPABILITY capability;
+
+        status = LibLocateProtocol(&tpm2_guid, (void **) &tcg);
+
+        if (EFI_ERROR(status))
+                return NULL;
+
+        capability.Size = (UINT8) sizeof(capability);
+        status = uefi_call_wrapper(tcg->GetCapability, 2, tcg, &capability);
+
+        if (EFI_ERROR(status))
+                return NULL;
+
+        if (!capability.TPMPresentFlag)
+                return NULL;
+
+        return tcg;
+}
+
+EFI_STATUS tpm_log_event(UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer, UINTN buffer_size, const CHAR16 *description) {
+        EFI_TCG *tpm1;
+        EFI_TCG2 *tpm2;
+
+        tpm2 = tcg2_interface_check();
+        if (tpm2)
+                return tpm2_measure_to_pcr_and_event_log(tpm2, pcrindex, buffer, buffer_size, description);
+
+        tpm1 = tcg1_interface_check();
+        if (tpm1)
+                return tpm1_measure_to_pcr_and_event_log(tpm1, pcrindex, buffer, buffer_size, description);
+
+        /* No active TPM found, so don't return an error */
+        return EFI_SUCCESS;
+}
+
+#endif
diff --git a/src/boot/efi/measure.h b/src/boot/efi/measure.h
new file mode 100644
index 0000000000..a2cfe817d0
--- /dev/null
+++ b/src/boot/efi/measure.h
@@ -0,0 +1,21 @@
+/*
+ * This program 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.
+ *
+ * This program 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.
+ *
+ */
+#ifndef __SDBOOT_MEASURE_H
+#define __SDBOOT_MEASURE_H
+
+#ifndef SD_TPM_PCR
+#define SD_TPM_PCR 8
+#endif
+
+EFI_STATUS tpm_log_event(UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer, UINTN buffer_size, const CHAR16 *description);
+#endif
diff --git a/src/boot/efi/stub.c b/src/boot/efi/stub.c
index 9633bc1792..1e250f34f4 100644
--- a/src/boot/efi/stub.c
+++ b/src/boot/efi/stub.c
@@ -20,6 +20,7 @@
 #include "pefile.h"
 #include "splash.h"
 #include "util.h"
+#include "measure.h"
 
 /* magic string to find in the binary image */
 static const char __attribute__((used)) magic[] = "#### LoaderInfo: systemd-stub " VERSION " ####";
@@ -97,6 +98,18 @@ EFI_STATUS efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *sys_table) {
                 for (i = 0; i < cmdline_len; i++)
                         line[i] = options[i];
                 cmdline = line;
+
+#ifdef SD_BOOT_LOG_TPM
+                /* Try to log any options to the TPM, escpecially manually edited options */
+                err = tpm_log_event(SD_TPM_PCR,
+                                    (EFI_PHYSICAL_ADDRESS) loaded_image->LoadOptions,
+                                    loaded_image->LoadOptionsSize, loaded_image->LoadOptions);
+                if (EFI_ERROR(err)) {
+                        Print(L"Unable to add image options measurement: %r", err);
+                        uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
+                        return err;
+                }
+#endif
         }
 
         /* export the device path this image is started from */