src/security/vboot/antirollback.h

   1 /* SPDX-License-Identifier: BSD-3-Clause */
   2
   3 /*
   4  * Functions for querying, manipulating and locking rollback indices
   5  * stored in the TPM NVRAM.
   6  */
   7
   8 #ifndef ANTIROLLBACK_H_
   9 #define ANTIROLLBACK_H_
  10
  11 #include <types.h>
  12 #include <security/tpm/tspi.h>
  13 #include <security/tpm/tss_errors.h>
  14 #include <vb2_sha.h>
  15
  16 struct vb2_context;
  17 enum vb2_pcr_digest;
  18
  19 /* TPM NVRAM location indices. */
  20 #define FIRMWARE_NV_INDEX               0x1007
  21 #define KERNEL_NV_INDEX                 0x1008
  22 /* 0x1009 used to be used as a backup space. Think of conflicts if you
  23  * want to use 0x1009 for something else. */
  24 #define BACKUP_NV_INDEX                 0x1009
  25 #define FWMP_NV_INDEX                   0x100a
  26 /* 0x100b: Hash of MRC_CACHE training data for recovery boot */
  27 #define MRC_REC_HASH_NV_INDEX           0x100b
  28 /* 0x100c: OOBE autoconfig public key hashes */
  29 /* 0x100d: Hash of MRC_CACHE training data for non-recovery boot */
  30 #define MRC_RW_HASH_NV_INDEX            0x100d
  31 #define HASH_NV_SIZE                    VB2_SHA256_DIGEST_SIZE
  32 #define ENT_ROLLBACK_SPACE_INDEX        0x100e
  33 #define VBIOS_CACHE_NV_INDEX            0x100f
  34 /* Widevine Secure Counter space */
  35 #define WIDEVINE_COUNTER_NV_INDEX(n)    (0x3000 + (n))
  36 #define NUM_WIDEVINE_COUNTERS           4
  37 #define WIDEVINE_COUNTER_NAME           "Widevine Secure Counter"
  38 #define WIDEVINE_COUNTER_SIZE           sizeof(uint64_t)
  39 /* Zero-Touch Enrollment related spaces */
  40 #define ZTE_BOARD_ID_NV_INDEX           0x3fff00
  41 #define ZTE_RMA_SN_BITS_INDEX           0x3fff01
  42 #define ZTE_RMA_BYTES_COUNTER_INDEX     0x3fff04
  43
  44 /* Structure definitions for TPM spaces */
  45
  46 /* Flags for firmware space */
  47
  48 /*
  49  * Last boot was developer mode.  TPM ownership is cleared when transitioning
  50  * to/from developer mode.
  51  */
  52 #define FLAG_LAST_BOOT_DEVELOPER 0x01
  53
  54 /* All functions return TPM_SUCCESS (zero) if successful, non-zero if error */
  55
  56 tpm_result_t antirollback_read_space_firmware(struct vb2_context *ctx);
  57
  58 /**
  59  * Write may be called if the versions change.
  60  */
  61 tpm_result_t antirollback_write_space_firmware(struct vb2_context *ctx);
  62
  63 /**
  64  * Read and write kernel space in TPM.
  65  */
  66 tpm_result_t antirollback_read_space_kernel(struct vb2_context *ctx);
  67 tpm_result_t antirollback_write_space_kernel(struct vb2_context *ctx);
  68
  69 /**
  70  * Lock must be called.
  71  */
  72 tpm_result_t antirollback_lock_space_firmware(void);
  73
  74 /*
  75  * Read MRC hash data from TPM.
  76  * @param index index into TPM NVRAM where hash is stored The index
  77  *              can be set to either MRC_REC_HASH_NV_INDEX or
  78  *              MRC_RW_HASH_NV_INDEX depending upon whether we are
  79  *              booting in recovery or normal mode.
  80  * @param data  pointer to buffer where hash from TPM read into
  81  * @param size  size of buffer
  82  */
  83 tpm_result_t antirollback_read_space_mrc_hash(uint32_t index, uint8_t *data, uint32_t size);
  84 /*
  85  * Write new hash data to MRC space in TPM.\
  86  * @param index index into TPM NVRAM where hash is stored The index
  87  *              can be set to either MRC_REC_HASH_NV_INDEX or
  88  *              MRC_RW_HASH_NV_INDEX depending upon whether we are
  89  *              booting in recovery or normal mode.
  90  * @param data  pointer to buffer of hash value to be written
  91  * @param size  size of buffer
  92 */
  93 tpm_result_t antirollback_write_space_mrc_hash(uint32_t index, const uint8_t *data,
  94                                            uint32_t size);
  95 /*
  96  * Lock down MRC hash space in TPM.
  97  * @param index index into TPM NVRAM where hash is stored The index
  98  *              can be set to either MRC_REC_HASH_NV_INDEX or
  99  *              MRC_RW_HASH_NV_INDEX depending upon whether we are
 100  *              booting in recovery or normal mode.
 101 */
 102 tpm_result_t antirollback_lock_space_mrc_hash(uint32_t index);
 103
 104 /*
 105  * Read VBIOS hash data from TPM.
 106  * @param data  pointer to buffer where hash from TPM read into
 107  * @param size  size of buffer
 108  */
 109 tpm_result_t antirollback_read_space_vbios_hash(uint8_t *data, uint32_t size);
 110 /*
 111  * Write new hash data to VBIOS space in TPM.
 112  * @param data  pointer to buffer of hash value to be written
 113  * @param size  size of buffer
 114 */
 115 tpm_result_t antirollback_write_space_vbios_hash(const uint8_t *data, uint32_t size);
 116
 117 #endif  /* ANTIROLLBACK_H_ */