diff options
author | Daisuke Nojiri <dnojiri@chromium.org> | 2014-07-02 08:37:23 -0700 |
---|---|---|
committer | Marc Jones <marc.jones@se-eng.com> | 2015-01-27 01:43:57 +0100 |
commit | efb5cde87fb0afef7a0e3c1c6bf3a7cc9cb8dbeb (patch) | |
tree | beb9af9b1610e26fdc7f606643f36d0c196e052a /src/vendorcode/google/chromeos/antirollback.c | |
parent | 3c21e4687bae7169ee8c3b07cad095cf35106ecb (diff) |
vboot2: copy tlcl from vboot_reference as a preparation for vboot2 integration
vboot2 abtracts tpm storage as some 'secure' space. Thus, it's firmware's
responsibility to handle vboot specific operations with tpm. This CL just copies
related files from vboot_reference so that we can see how code was modified in
the next CL. Note rollback_index.c/h were renamed to antirollback.c/h.
TEST=none
BUG=none
Branch=none
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Change-Id: I1792a622058f70a8fcd3c4037547539ad2870420
Original-Reviewed-on: https://chromium-review.googlesource.com/206462
Original-Commit-Queue: Daisuke Nojiri <dnojiri@chromium.org>
Original-Tested-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Reviewed-by: Randall Spangler <rspangler@chromium.org>
(cherry picked from commit 2ae188b29242bf09c5e79e31f98b330a30bf7b93)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: I5fa5a636003e8472127194e961fea4309489b1d9
Reviewed-on: http://review.coreboot.org/8164
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
Diffstat (limited to 'src/vendorcode/google/chromeos/antirollback.c')
-rw-r--r-- | src/vendorcode/google/chromeos/antirollback.c | 676 |
1 files changed, 676 insertions, 0 deletions
diff --git a/src/vendorcode/google/chromeos/antirollback.c b/src/vendorcode/google/chromeos/antirollback.c new file mode 100644 index 0000000000..306e90329b --- /dev/null +++ b/src/vendorcode/google/chromeos/antirollback.c @@ -0,0 +1,676 @@ +/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * Functions for querying, manipulating and locking rollback indices + * stored in the TPM NVRAM. + */ + +#include "sysincludes.h" + +#include "crc8.h" +#include "rollback_index.h" +#include "tlcl.h" +#include "tss_constants.h" +#include "utility.h" +#include "vboot_api.h" + +#ifndef offsetof +#define offsetof(A,B) __builtin_offsetof(A,B) +#endif + +/* + * Provide protoypes for functions not in the header file. These prototypes + * fix -Wmissing-prototypes warnings. + */ +uint32_t ReadSpaceFirmware(RollbackSpaceFirmware *rsf); +uint32_t WriteSpaceFirmware(RollbackSpaceFirmware *rsf); +uint32_t ReadSpaceKernel(RollbackSpaceKernel *rsk); +uint32_t WriteSpaceKernel(RollbackSpaceKernel *rsk); + +#ifdef FOR_TEST +/* + * Compiling for unit test, so we need the real implementations of + * rollback functions. The unit test mocks the underlying tlcl + * functions, so this is ok to run on the host. + */ +#undef CHROMEOS_ENVIRONMENT +#undef DISABLE_ROLLBACK_TPM +#endif + +#define RETURN_ON_FAILURE(tpm_command) do { \ + uint32_t result_; \ + if ((result_ = (tpm_command)) != TPM_SUCCESS) { \ + VBDEBUG(("Rollback: %08x returned by " #tpm_command \ + "\n", (int)result_)); \ + return result_; \ + } \ + } while (0) + + +uint32_t TPMClearAndReenable(void) +{ + VBDEBUG(("TPM: Clear and re-enable\n")); + RETURN_ON_FAILURE(TlclForceClear()); + RETURN_ON_FAILURE(TlclSetEnable()); + RETURN_ON_FAILURE(TlclSetDeactivated(0)); + + return TPM_SUCCESS; +} + +uint32_t SafeWrite(uint32_t index, const void *data, uint32_t length) +{ + uint32_t result = TlclWrite(index, data, length); + if (result == TPM_E_MAXNVWRITES) { + RETURN_ON_FAILURE(TPMClearAndReenable()); + return TlclWrite(index, data, length); + } else { + return result; + } +} + +uint32_t SafeDefineSpace(uint32_t index, uint32_t perm, uint32_t size) +{ + uint32_t result = TlclDefineSpace(index, perm, size); + if (result == TPM_E_MAXNVWRITES) { + RETURN_ON_FAILURE(TPMClearAndReenable()); + return TlclDefineSpace(index, perm, size); + } else { + return result; + } +} + +/* Functions to read and write firmware and kernel spaces. */ +uint32_t ReadSpaceFirmware(RollbackSpaceFirmware *rsf) +{ + uint32_t r; + int attempts = 3; + + while (attempts--) { + r = TlclRead(FIRMWARE_NV_INDEX, rsf, + sizeof(RollbackSpaceFirmware)); + if (r != TPM_SUCCESS) + return r; + + /* + * No CRC in this version, so we'll create one when we write + * it. Note that we're marking this as version 2, not + * ROLLBACK_SPACE_FIRMWARE_VERSION, because version 2 just + * added the CRC. Later versions will need to set default + * values for any extra fields explicitly (probably here). + */ + if (rsf->struct_version < 2) { + /* Danger Will Robinson! Danger! */ + rsf->struct_version = 2; + return TPM_SUCCESS; + } + + /* + * If the CRC is good, we're done. If it's bad, try a couple + * more times to see if it gets better before we give up. It + * could just be noise. + */ + if (rsf->crc8 == Crc8(rsf, + offsetof(RollbackSpaceFirmware, crc8))) + return TPM_SUCCESS; + + VBDEBUG(("TPM: %s() - bad CRC\n", __func__)); + } + + VBDEBUG(("TPM: %s() - too many bad CRCs, giving up\n", __func__)); + return TPM_E_CORRUPTED_STATE; +} + +uint32_t WriteSpaceFirmware(RollbackSpaceFirmware *rsf) +{ + RollbackSpaceFirmware rsf2; + uint32_t r; + int attempts = 3; + + /* All writes should use struct_version 2 or greater. */ + if (rsf->struct_version < 2) + rsf->struct_version = 2; + rsf->crc8 = Crc8(rsf, offsetof(RollbackSpaceFirmware, crc8)); + + while (attempts--) { + r = SafeWrite(FIRMWARE_NV_INDEX, rsf, + sizeof(RollbackSpaceFirmware)); + /* Can't write, not gonna try again */ + if (r != TPM_SUCCESS) + return r; + + /* Read it back to be sure it got the right values. */ + r = ReadSpaceFirmware(&rsf2); /* This checks the CRC */ + if (r == TPM_SUCCESS) + return r; + + VBDEBUG(("TPM: %s() - bad CRC\n", __func__)); + /* Try writing it again. Maybe it was garbled on the way out. */ + } + + VBDEBUG(("TPM: %s() - too many bad CRCs, giving up\n", __func__)); + return TPM_E_CORRUPTED_STATE; +} + +uint32_t SetVirtualDevMode(int val) +{ + RollbackSpaceFirmware rsf; + + VBDEBUG(("TPM: Entering %s()\n", __func__)); + if (TPM_SUCCESS != ReadSpaceFirmware(&rsf)) + return VBERROR_TPM_FIRMWARE_SETUP; + + VBDEBUG(("TPM: flags were 0x%02x\n", rsf.flags)); + if (val) + rsf.flags |= FLAG_VIRTUAL_DEV_MODE_ON; + else + rsf.flags &= ~FLAG_VIRTUAL_DEV_MODE_ON; + /* + * NOTE: This doesn't update the FLAG_LAST_BOOT_DEVELOPER bit. That + * will be done by SetupTPM() on the next boot. + */ + VBDEBUG(("TPM: flags are now 0x%02x\n", rsf.flags)); + + if (TPM_SUCCESS != WriteSpaceFirmware(&rsf)) + return VBERROR_TPM_SET_BOOT_MODE_STATE; + + VBDEBUG(("TPM: Leaving %s()\n", __func__)); + return VBERROR_SUCCESS; +} + +uint32_t ReadSpaceKernel(RollbackSpaceKernel *rsk) +{ + uint32_t r; + int attempts = 3; + + while (attempts--) { + r = TlclRead(KERNEL_NV_INDEX, rsk, sizeof(RollbackSpaceKernel)); + if (r != TPM_SUCCESS) + return r; + + /* + * No CRC in this version, so we'll create one when we write + * it. Note that we're marking this as version 2, not + * ROLLBACK_SPACE_KERNEL_VERSION, because version 2 just added + * the CRC. Later versions will need to set default values for + * any extra fields explicitly (probably here). + */ + if (rsk->struct_version < 2) { + /* Danger Will Robinson! Danger! */ + rsk->struct_version = 2; + return TPM_SUCCESS; + } + + /* + * If the CRC is good, we're done. If it's bad, try a couple + * more times to see if it gets better before we give up. It + * could just be noise. + */ + if (rsk->crc8 == Crc8(rsk, offsetof(RollbackSpaceKernel, crc8))) + return TPM_SUCCESS; + + VBDEBUG(("TPM: %s() - bad CRC\n", __func__)); + } + + VBDEBUG(("TPM: %s() - too many bad CRCs, giving up\n", __func__)); + return TPM_E_CORRUPTED_STATE; +} + +uint32_t WriteSpaceKernel(RollbackSpaceKernel *rsk) +{ + RollbackSpaceKernel rsk2; + uint32_t r; + int attempts = 3; + + /* All writes should use struct_version 2 or greater. */ + if (rsk->struct_version < 2) + rsk->struct_version = 2; + rsk->crc8 = Crc8(rsk, offsetof(RollbackSpaceKernel, crc8)); + + while (attempts--) { + r = SafeWrite(KERNEL_NV_INDEX, rsk, + sizeof(RollbackSpaceKernel)); + /* Can't write, not gonna try again */ + if (r != TPM_SUCCESS) + return r; + + /* Read it back to be sure it got the right values. */ + r = ReadSpaceKernel(&rsk2); /* This checks the CRC */ + if (r == TPM_SUCCESS) + return r; + + VBDEBUG(("TPM: %s() - bad CRC\n", __func__)); + /* Try writing it again. Maybe it was garbled on the way out. */ + } + + VBDEBUG(("TPM: %s() - too many bad CRCs, giving up\n", __func__)); + return TPM_E_CORRUPTED_STATE; +} + +uint32_t OneTimeInitializeTPM(RollbackSpaceFirmware *rsf, + RollbackSpaceKernel *rsk) +{ + static const RollbackSpaceFirmware rsf_init = { + .struct_version = ROLLBACK_SPACE_FIRMWARE_VERSION, + }; + static const RollbackSpaceKernel rsk_init = { + .struct_version = ROLLBACK_SPACE_KERNEL_VERSION, + .uid = ROLLBACK_SPACE_KERNEL_UID, + }; + TPM_PERMANENT_FLAGS pflags; + uint32_t result; + + VBDEBUG(("TPM: One-time initialization\n")); + + /* + * Do a full test. This only happens the first time the device is + * turned on in the factory, so performance is not an issue. This is + * almost certainly not necessary, but it gives us more confidence + * about some code paths below that are difficult to + * test---specifically the ones that set lifetime flags, and are only + * executed once per physical TPM. + */ + result = TlclSelfTestFull(); + if (result != TPM_SUCCESS) + return result; + + result = TlclGetPermanentFlags(&pflags); + if (result != TPM_SUCCESS) + return result; + + /* + * TPM may come from the factory without physical presence finalized. + * Fix if necessary. + */ + VBDEBUG(("TPM: physicalPresenceLifetimeLock=%d\n", + pflags.physicalPresenceLifetimeLock)); + if (!pflags.physicalPresenceLifetimeLock) { + VBDEBUG(("TPM: Finalizing physical presence\n")); + RETURN_ON_FAILURE(TlclFinalizePhysicalPresence()); + } + + /* + * The TPM will not enforce the NV authorization restrictions until the + * execution of a TPM_NV_DefineSpace with the handle of + * TPM_NV_INDEX_LOCK. Here we create that space if it doesn't already + * exist. */ + VBDEBUG(("TPM: nvLocked=%d\n", pflags.nvLocked)); + if (!pflags.nvLocked) { + VBDEBUG(("TPM: Enabling NV locking\n")); + RETURN_ON_FAILURE(TlclSetNvLocked()); + } + + /* Clear TPM owner, in case the TPM is already owned for some reason. */ + VBDEBUG(("TPM: Clearing owner\n")); + RETURN_ON_FAILURE(TPMClearAndReenable()); + + /* Initializes the firmware and kernel spaces */ + Memcpy(rsf, &rsf_init, sizeof(RollbackSpaceFirmware)); + Memcpy(rsk, &rsk_init, sizeof(RollbackSpaceKernel)); + + /* Define the backup space. No need to initialize it, though. */ + RETURN_ON_FAILURE(SafeDefineSpace( + BACKUP_NV_INDEX, TPM_NV_PER_PPWRITE, BACKUP_NV_SIZE)); + + /* Define and initialize the kernel space */ + RETURN_ON_FAILURE(SafeDefineSpace(KERNEL_NV_INDEX, TPM_NV_PER_PPWRITE, + sizeof(RollbackSpaceKernel))); + RETURN_ON_FAILURE(WriteSpaceKernel(rsk)); + + /* Do the firmware space last, so we retry if we don't get this far. */ + RETURN_ON_FAILURE(SafeDefineSpace( + FIRMWARE_NV_INDEX, + TPM_NV_PER_GLOBALLOCK | TPM_NV_PER_PPWRITE, + sizeof(RollbackSpaceFirmware))); + RETURN_ON_FAILURE(WriteSpaceFirmware(rsf)); + + return TPM_SUCCESS; +} + + +/* + * SetupTPM starts the TPM and establishes the root of trust for the + * anti-rollback mechanism. SetupTPM can fail for three reasons. 1 A bug. 2 a + * TPM hardware failure. 3 An unexpected TPM state due to some attack. In + * general we cannot easily distinguish the kind of failure, so our strategy is + * to reboot in recovery mode in all cases. The recovery mode calls SetupTPM + * again, which executes (almost) the same sequence of operations. There is a + * good chance that, if recovery mode was entered because of a TPM failure, the + * failure will repeat itself. (In general this is impossible to guarantee + * because we have no way of creating the exact TPM initial state at the + * previous boot.) In recovery mode, we ignore the failure and continue, thus + * giving the recovery kernel a chance to fix things (that's why we don't set + * bGlobalLock). The choice is between a knowingly insecure device and a + * bricked device. + * + * As a side note, observe that we go through considerable hoops to avoid using + * the STCLEAR permissions for the index spaces. We do this to avoid writing + * to the TPM flashram at every reboot or wake-up, because of concerns about + * the durability of the NVRAM. + */ +uint32_t SetupTPM(int developer_mode, int disable_dev_request, + int clear_tpm_owner_request, RollbackSpaceFirmware* rsf) +{ + uint8_t in_flags; + uint8_t disable; + uint8_t deactivated; + uint32_t result; + uint32_t versions; + + RETURN_ON_FAILURE(TlclLibInit()); + +#ifdef TEGRA_SOFT_REBOOT_WORKAROUND + result = TlclStartup(); + if (result == TPM_E_INVALID_POSTINIT) { + /* + * Some prototype hardware doesn't reset the TPM on a CPU + * reset. We do a hard reset to get around this. + */ + VBDEBUG(("TPM: soft reset detected\n", result)); + return TPM_E_MUST_REBOOT; + } else if (result != TPM_SUCCESS) { + VBDEBUG(("TPM: TlclStartup returned %08x\n", result)); + return result; + } +#else + RETURN_ON_FAILURE(TlclStartup()); +#endif + + /* + * Some TPMs start the self test automatically at power on. In that case we + * don't need to call ContinueSelfTest. On some (other) TPMs, + * ContinueSelfTest may block. In that case, we definitely don't want to + * call it here. For TPMs in the intersection of these two sets, we're + * screwed. (In other words: TPMs that require manually starting the + * self-test AND block will have poor performance until we split + * TlclSendReceive() into Send() and Receive(), and have a state machine to + * control setup.) + * + * This comment is likely to become obsolete in the near future, so don't + * trust it. It may have not been updated. + */ +#ifdef TPM_MANUAL_SELFTEST +#ifdef TPM_BLOCKING_CONTINUESELFTEST +#warning "lousy TPM!" +#endif + RETURN_ON_FAILURE(TlclContinueSelfTest()); +#endif + result = TlclAssertPhysicalPresence(); + if (result != TPM_SUCCESS) { + /* + * It is possible that the TPM was delivered with the physical + * presence command disabled. This tries enabling it, then + * tries asserting PP again. + */ + RETURN_ON_FAILURE(TlclPhysicalPresenceCMDEnable()); + RETURN_ON_FAILURE(TlclAssertPhysicalPresence()); + } + + /* Check that the TPM is enabled and activated. */ + RETURN_ON_FAILURE(TlclGetFlags(&disable, &deactivated, NULL)); + if (disable || deactivated) { + VBDEBUG(("TPM: disabled (%d) or deactivated (%d). Fixing...\n", + disable, deactivated)); + RETURN_ON_FAILURE(TlclSetEnable()); + RETURN_ON_FAILURE(TlclSetDeactivated(0)); + VBDEBUG(("TPM: Must reboot to re-enable\n")); + return TPM_E_MUST_REBOOT; + } + + /* Read the firmware space. */ + result = ReadSpaceFirmware(rsf); + if (TPM_E_BADINDEX == result) { + RollbackSpaceKernel rsk; + + /* + * This is the first time we've run, and the TPM has not been + * initialized. Initialize it. + */ + VBDEBUG(("TPM: Not initialized yet.\n")); + RETURN_ON_FAILURE(OneTimeInitializeTPM(rsf, &rsk)); + } else if (TPM_SUCCESS != result) { + VBDEBUG(("TPM: Firmware space in a bad state; giving up.\n")); + return TPM_E_CORRUPTED_STATE; + } + Memcpy(&versions, &rsf->fw_versions, sizeof(versions)); + VBDEBUG(("TPM: Firmware space sv%d f%x v%x\n", + rsf->struct_version, rsf->flags, versions)); + in_flags = rsf->flags; + + /* If we've been asked to clear the virtual dev-mode flag, do so now */ + if (disable_dev_request) { + rsf->flags &= ~FLAG_VIRTUAL_DEV_MODE_ON; + VBDEBUG(("TPM: Clearing virt dev-switch: f%x\n", rsf->flags)); + } + + /* + * The developer_mode value that's passed in is only set by a hardware + * dev-switch. We should OR it with the virtual switch, whether or not + * the virtual switch is used. If it's not used, it shouldn't change, + * so it doesn't matter. + */ + if (rsf->flags & FLAG_VIRTUAL_DEV_MODE_ON) + developer_mode = 1; + + /* + * Clear ownership if developer flag has toggled, or if an owner-clear + * has been requested. + */ + if ((developer_mode ? FLAG_LAST_BOOT_DEVELOPER : 0) != + (in_flags & FLAG_LAST_BOOT_DEVELOPER)) { + VBDEBUG(("TPM: Developer flag changed; clearing owner.\n")); + RETURN_ON_FAILURE(TPMClearAndReenable()); + } else if (clear_tpm_owner_request) { + VBDEBUG(("TPM: Clearing owner as specifically requested.\n")); + RETURN_ON_FAILURE(TPMClearAndReenable()); + } + + if (developer_mode) + rsf->flags |= FLAG_LAST_BOOT_DEVELOPER; + else + rsf->flags &= ~FLAG_LAST_BOOT_DEVELOPER; + + + /* If firmware space is dirty, flush it back to the TPM */ + if (rsf->flags != in_flags) { + VBDEBUG(("TPM: Updating firmware space.\n")); + RETURN_ON_FAILURE(WriteSpaceFirmware(rsf)); + } + + VBDEBUG(("TPM: SetupTPM() succeeded\n")); + return TPM_SUCCESS; +} + + +#ifdef DISABLE_ROLLBACK_TPM +/* Dummy implementations which don't support TPM rollback protection */ + +uint32_t RollbackS3Resume(void) +{ +#ifndef CHROMEOS_ENVIRONMENT + /* + * Initialize the TPM, but ignore return codes. In ChromeOS + * environment, don't even talk to the TPM. + */ + TlclLibInit(); + TlclResume(); +#endif + return TPM_SUCCESS; +} + +uint32_t RollbackFirmwareSetup(int is_hw_dev, + int disable_dev_request, + int clear_tpm_owner_request, + int *is_virt_dev, uint32_t *version) +{ +#ifndef CHROMEOS_ENVIRONMENT + /* + * Initialize the TPM, but ignores return codes. In ChromeOS + * environment, don't even talk to the TPM. + */ + TlclLibInit(); + TlclStartup(); + TlclContinueSelfTest(); +#endif + *is_virt_dev = 0; + *version = 0; + return TPM_SUCCESS; +} + +uint32_t RollbackFirmwareWrite(uint32_t version) +{ + return TPM_SUCCESS; +} + +uint32_t RollbackFirmwareLock(void) +{ + return TPM_SUCCESS; +} + +uint32_t RollbackKernelRead(uint32_t* version) +{ + *version = 0; + return TPM_SUCCESS; +} + +uint32_t RollbackKernelWrite(uint32_t version) +{ + return TPM_SUCCESS; +} + +uint32_t RollbackBackupRead(uint8_t *raw) +{ + return TPM_SUCCESS; +} + +uint32_t RollbackBackupWrite(uint8_t *raw) +{ + return TPM_SUCCESS; +} + +uint32_t RollbackKernelLock(int recovery_mode) +{ + return TPM_SUCCESS; +} + +#else + +uint32_t RollbackS3Resume(void) +{ + uint32_t result; + RETURN_ON_FAILURE(TlclLibInit()); + result = TlclResume(); + if (result == TPM_E_INVALID_POSTINIT) { + /* + * We're on a platform where the TPM maintains power in S3, so + * it's already initialized. + */ + return TPM_SUCCESS; + } + return result; +} + +uint32_t RollbackFirmwareSetup(int is_hw_dev, + int disable_dev_request, + int clear_tpm_owner_request, + int *is_virt_dev, uint32_t *version) +{ + RollbackSpaceFirmware rsf; + + /* Set version to 0 in case we fail */ + *version = 0; + + RETURN_ON_FAILURE(SetupTPM(is_hw_dev, disable_dev_request, + clear_tpm_owner_request, &rsf)); + Memcpy(version, &rsf.fw_versions, sizeof(*version)); + *is_virt_dev = (rsf.flags & FLAG_VIRTUAL_DEV_MODE_ON) ? 1 : 0; + VBDEBUG(("TPM: RollbackFirmwareSetup %x\n", (int)*version)); + return TPM_SUCCESS; +} + +uint32_t RollbackFirmwareWrite(uint32_t version) +{ + RollbackSpaceFirmware rsf; + uint32_t old_version; + + RETURN_ON_FAILURE(ReadSpaceFirmware(&rsf)); + Memcpy(&old_version, &rsf.fw_versions, sizeof(old_version)); + VBDEBUG(("TPM: RollbackFirmwareWrite %x --> %x\n", (int)old_version, + (int)version)); + Memcpy(&rsf.fw_versions, &version, sizeof(version)); + return WriteSpaceFirmware(&rsf); +} + +uint32_t RollbackFirmwareLock(void) +{ + return TlclSetGlobalLock(); +} + +uint32_t RollbackKernelRead(uint32_t* version) +{ + RollbackSpaceKernel rsk; + uint32_t perms, uid; + + /* + * Read the kernel space and verify its permissions. If the kernel + * space has the wrong permission, or it doesn't contain the right + * identifier, we give up. This will need to be fixed by the + * recovery kernel. We have to worry about this because at any time + * (even with PP turned off) the TPM owner can remove and redefine a + * PP-protected space (but not write to it). + */ + RETURN_ON_FAILURE(ReadSpaceKernel(&rsk)); + RETURN_ON_FAILURE(TlclGetPermissions(KERNEL_NV_INDEX, &perms)); + Memcpy(&uid, &rsk.uid, sizeof(uid)); + if (TPM_NV_PER_PPWRITE != perms || ROLLBACK_SPACE_KERNEL_UID != uid) + return TPM_E_CORRUPTED_STATE; + + Memcpy(version, &rsk.kernel_versions, sizeof(*version)); + VBDEBUG(("TPM: RollbackKernelRead %x\n", (int)*version)); + return TPM_SUCCESS; +} + +uint32_t RollbackKernelWrite(uint32_t version) +{ + RollbackSpaceKernel rsk; + uint32_t old_version; + RETURN_ON_FAILURE(ReadSpaceKernel(&rsk)); + Memcpy(&old_version, &rsk.kernel_versions, sizeof(old_version)); + VBDEBUG(("TPM: RollbackKernelWrite %x --> %x\n", + (int)old_version, (int)version)); + Memcpy(&rsk.kernel_versions, &version, sizeof(version)); + return WriteSpaceKernel(&rsk); +} + +/* + * We don't really care whether the TPM owner has been messing with this or + * not. We lock it along with the Kernel space just to avoid problems, but it's + * only useful in dev-mode and only when the battery has been drained + * completely. There aren't any security issues. It's just in the TPM because + * we don't have any other place to keep it. + */ +uint32_t RollbackBackupRead(uint8_t *raw) +{ + uint32_t r; + r = TlclRead(BACKUP_NV_INDEX, raw, BACKUP_NV_SIZE); + VBDEBUG(("TPM: %s returning 0x%x\n", __func__, r)); + return r; +} + +uint32_t RollbackBackupWrite(uint8_t *raw) +{ + uint32_t r; + r = TlclWrite(BACKUP_NV_INDEX, raw, BACKUP_NV_SIZE); + VBDEBUG(("TPM: %s returning 0x%x\n", __func__, r)); + return r; +} + +uint32_t RollbackKernelLock(int recovery_mode) +{ + if (recovery_mode) + return TPM_SUCCESS; + else + return TlclLockPhysicalPresence(); +} + +#endif /* DISABLE_ROLLBACK_TPM */ |