diff options
Diffstat (limited to 'src/vendorcode/google/chromeos/vboot2/antirollback.c')
| -rw-r--r-- | src/vendorcode/google/chromeos/vboot2/antirollback.c | 187 |
1 files changed, 131 insertions, 56 deletions
diff --git a/src/vendorcode/google/chromeos/vboot2/antirollback.c b/src/vendorcode/google/chromeos/vboot2/antirollback.c index fbc6d42a18..621758ad47 100644 --- a/src/vendorcode/google/chromeos/vboot2/antirollback.c +++ b/src/vendorcode/google/chromeos/vboot2/antirollback.c @@ -10,8 +10,8 @@ #include <stdlib.h> #include <string.h> #include <tpm_lite/tlcl.h> -#include <tpm_lite/tss_constants.h> #include <vb2_api.h> +#include <console/console.h> #ifndef offsetof #define offsetof(A,B) __builtin_offsetof(A,B) @@ -36,6 +36,8 @@ } while (0) +static uint32_t safe_write(uint32_t index, const void *data, uint32_t length); + uint32_t tpm_extend_pcr(struct vb2_context *ctx, int pcr, enum vb2_pcr_digest which_digest) { @@ -52,38 +54,6 @@ uint32_t tpm_extend_pcr(struct vb2_context *ctx, int pcr, return tlcl_extend(pcr, buffer, NULL); } -uint32_t tpm_clear_and_reenable(void) -{ - VBDEBUG("TPM: Clear and re-enable\n"); - RETURN_ON_FAILURE(tlcl_force_clear()); - RETURN_ON_FAILURE(tlcl_set_enable()); - RETURN_ON_FAILURE(tlcl_set_deactivated(0)); - - return TPM_SUCCESS; -} - -uint32_t safe_write(uint32_t index, const void *data, uint32_t length) -{ - uint32_t result = tlcl_write(index, data, length); - if (result == TPM_E_MAXNVWRITES) { - RETURN_ON_FAILURE(tpm_clear_and_reenable()); - return tlcl_write(index, data, length); - } else { - return result; - } -} - -uint32_t safe_define_space(uint32_t index, uint32_t perm, uint32_t size) -{ - uint32_t result = tlcl_define_space(index, perm, size); - if (result == TPM_E_MAXNVWRITES) { - RETURN_ON_FAILURE(tpm_clear_and_reenable()); - return tlcl_define_space(index, perm, size); - } else { - return result; - } -} - static uint32_t read_space_firmware(struct vb2_context *ctx) { int attempts = 3; @@ -135,33 +105,110 @@ static uint32_t write_secdata(uint32_t index, return TPM_E_CORRUPTED_STATE; } -uint32_t factory_initialize_tpm(struct vb2_context *ctx) +/* + * This is derived from rollback_index.h of vboot_reference. see struct + * RollbackSpaceKernel for details. + */ +static const uint8_t secdata_kernel[] = { + 0x02, + 0x4C, 0x57, 0x52, 0x47, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, + 0xE8, +}; + +#if IS_ENABLED(CONFIG_TPM2) + +/* Nothing special in the TPM2 path yet. */ +static uint32_t safe_write(uint32_t index, const void *data, uint32_t length) { - TPM_PERMANENT_FLAGS pflags; - uint32_t result; - /* this is derived from rollback_index.h of vboot_reference. see struct - * RollbackSpaceKernel for details. */ - static const uint8_t secdata_kernel[] = { - 0x02, - 0x4C, 0x57, 0x52, 0x47, - 0x00, 0x00, 0x00, 0x00, - 0x00, 0x00, 0x00, - 0xE8, - }; + return tlcl_write(index, data, length); +} - VBDEBUG("TPM: factory initialization\n"); +static uint32_t set_firmware_space(const void *firmware_blob) +{ + RETURN_ON_FAILURE(tlcl_define_space(FIRMWARE_NV_INDEX, + high_privilege, + VB2_SECDATA_SIZE)); + RETURN_ON_FAILURE(safe_write(FIRMWARE_NV_INDEX, firmware_blob, + VB2_SECDATA_SIZE)); + return TPM_SUCCESS; +} - /* - * 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 = tlcl_self_test_full(); - if (result != TPM_SUCCESS) +static uint32_t set_kernel_space(const void *kernel_blob) +{ + RETURN_ON_FAILURE(tlcl_define_space(KERNEL_NV_INDEX, + low_privilege, + sizeof(secdata_kernel))); + RETURN_ON_FAILURE(safe_write(KERNEL_NV_INDEX, kernel_blob, + sizeof(secdata_kernel))); + return TPM_SUCCESS; +} + +static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) +{ + RETURN_ON_FAILURE(set_firmware_space(ctx->secdata)); + RETURN_ON_FAILURE(set_kernel_space(secdata_kernel)); + return TPM_SUCCESS; +} + +uint32_t tpm_clear_and_reenable(void) +{ + VBDEBUG("TPM: Clear and re-enable\n"); + return TPM_SUCCESS; +} + +#else + +uint32_t tpm_clear_and_reenable(void) +{ + VBDEBUG("TPM: Clear and re-enable\n"); + RETURN_ON_FAILURE(tlcl_force_clear()); + RETURN_ON_FAILURE(tlcl_set_enable()); + RETURN_ON_FAILURE(tlcl_set_deactivated(0)); + + return TPM_SUCCESS; +} + +/** + * Like tlcl_write(), but checks for write errors due to hitting the 64-write + * limit and clears the TPM when that happens. This can only happen when the + * TPM is unowned, so it is OK to clear it (and we really have no choice). + * This is not expected to happen frequently, but it could happen. + */ + +static uint32_t safe_write(uint32_t index, const void *data, uint32_t length) +{ + uint32_t result = tlcl_write(index, data, length); + if (result == TPM_E_MAXNVWRITES) { + RETURN_ON_FAILURE(tpm_clear_and_reenable()); + return tlcl_write(index, data, length); + } else { return result; + } +} + +/** + * Similarly to safe_write(), this ensures we don't fail a DefineSpace because + * we hit the TPM write limit. This is even less likely to happen than with + * writes because we only define spaces once at initialization, but we'd + * rather be paranoid about this. + */ +static uint32_t safe_define_space(uint32_t index, uint32_t perm, uint32_t size) +{ + uint32_t result = tlcl_define_space(index, perm, size); + if (result == TPM_E_MAXNVWRITES) { + RETURN_ON_FAILURE(tpm_clear_and_reenable()); + return tlcl_define_space(index, perm, size); + } else { + return result; + } +} + +static uint32_t _factory_initialize_tpm(struct vb2_context *ctx) +{ + TPM_PERMANENT_FLAGS pflags; + uint32_t result; result = tlcl_get_permanent_flags(&pflags); if (result != TPM_SUCCESS) @@ -215,6 +262,34 @@ uint32_t factory_initialize_tpm(struct vb2_context *ctx) RETURN_ON_FAILURE(write_secdata(FIRMWARE_NV_INDEX, ctx->secdata, VB2_SECDATA_SIZE)); + return TPM_SUCCESS; +} +#endif + +uint32_t factory_initialize_tpm(struct vb2_context *ctx) +{ + uint32_t result; + + /* Defines and sets vb2 secdata space */ + vb2api_secdata_create(ctx); + + VBDEBUG("TPM: factory 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 = tlcl_self_test_full(); + if (result != TPM_SUCCESS) + return result; + + result = _factory_initialize_tpm(ctx); + if (result != TPM_SUCCESS) + return result; VBDEBUG("TPM: factory initialization successful\n"); |