% tpm2_policycommandcode(1) tpm2-tools | General Commands Manual

NAME

tpm2_policycommandcode(1) - Restrict TPM object authorization to specific TPM commands.

SYNOPSIS

tpm2_policycommandcode [OPTIONS] [ARGUMENT]

DESCRIPTION

tpm2_policycommandcode(1) - Restricts TPM object authorization to specific TPM commands. Useful when you want to allow only specific commands to interact with the TPM object.

As an argument it takes the command as an integer or friendly string value. Friendly string to COMMAND CODE mapping can be found in section COMMAND CODE MAPPINGS.

OPTIONS

  • -S, --session=FILE:

    A session file from tpm2_startauthsession(1)'s -S option.

  • -L, --policy=FILE:

    File to save the policy digest.

  • ARGUMENT the command line argument specifies TPM2 command code.

References

common options collection of common options that provide information many users may expect.

common tcti options collection of options used to configure the various known TCTI modules.

COMMAND CODE MAPPINGS

The friendly strings below can be used en lieu of the raw integer values.

-TPM2_CC_AC_GetCapability: 0x194 -TPM2_CC_AC_Send: 0x195 -TPM2_CC_ActivateCredential: 0x147 -TPM2_CC_Certify: 0x148 -TPM2_CC_CertifyCreation: 0x14a -TPM2_CC_ChangeEPS: 0x124 -TPM2_CC_ChangePPS: 0x125 -TPM2_CC_Clear: 0x126 -TPM2_CC_ClearControl: 0x127 -TPM2_CC_ClockRateAdjust: 0x130 -TPM2_CC_ClockSet: 0x128 -TPM2_CC_Commit: 0x18b -TPM2_CC_ContextLoad: 0x161 -TPM2_CC_ContextSave: 0x162 -TPM2_CC_Create: 0x153 -TPM2_CC_CreateLoaded: 0x191 -TPM2_CC_CreatePrimary: 0x131 -TPM2_CC_DictionaryAttackLockReset: 0x139 -TPM2_CC_DictionaryAttackParameters: 0x13a -TPM2_CC_Duplicate: 0x14b -TPM2_CC_ECC_Parameters: 0x178 -TPM2_CC_ECDH_KeyGen: 0x163 -TPM2_CC_ECDH_ZGen: 0x154 -TPM2_CC_EC_Ephemeral: 0x18e -TPM2_CC_EncryptDecrypt: 0x164 -TPM2_CC_EncryptDecrypt2: 0x193 -TPM2_CC_EventSequenceComplete: 0x185 -TPM2_CC_EvictControl: 0x120 -TPM2_CC_FieldUpgradeData: 0x141 -TPM2_CC_FieldUpgradeStart: 0x12f -TPM2_CC_FirmwareRead: 0x179 -TPM2_CC_FlushContext: 0x165 -TPM2_CC_GetCapability: 0x17a -TPM2_CC_GetCommandAuditDigest: 0x133 -TPM2_CC_GetRandom: 0x17b -TPM2_CC_GetSessionAuditDigest: 0x14d -TPM2_CC_GetTestResult: 0x17c -TPM2_CC_GetTime: 0x14c -TPM2_CC_Hash: 0x17d -TPM2_CC_HashSequenceStart: 0x186 -TPM2_CC_HierarchyChangeAuth: 0x129 -TPM2_CC_HierarchyControl: 0x121 -TPM2_CC_HMAC: 0x155 -TPM2_CC_HMAC_Start: 0x15b -TPM2_CC_Import: 0x156 -TPM2_CC_IncrementalSelfTest: 0x142 -TPM2_CC_Load: 0x157 -TPM2_CC_LoadExternal: 0x167 -TPM2_CC_MakeCredential: 0x168 -TPM2_CC_NV_Certify: 0x184 -TPM2_CC_NV_ChangeAuth: 0x13b -TPM2_CC_NV_DefineSpace: 0x12a -TPM2_CC_NV_Extend: 0x136 -TPM2_CC_NV_GlobalWriteLock: 0x132 -TPM2_CC_NV_Increment: 0x134 -TPM2_CC_NV_Read: 0x14e -TPM2_CC_NV_ReadLock: 0x14f -TPM2_CC_NV_ReadPublic: 0x169 -TPM2_CC_NV_SetBits: 0x135 -TPM2_CC_NV_UndefineSpace: 0x122 -TPM2_CC_NV_UndefineSpaceSpecial: 0x11f -TPM2_CC_NV_Write: 0x137 -TPM2_CC_NV_WriteLock: 0x138 -TPM2_CC_ObjectChangeAuth: 0x150 -TPM2_CC_PCR_Allocate: 0x12b -TPM2_CC_PCR_Event: 0x13c -TPM2_CC_PCR_Extend: 0x182 -TPM2_CC_PCR_Read: 0x17e -TPM2_CC_PCR_Reset: 0x13d -TPM2_CC_PCR_SetAuthPolicy: 0x12c -TPM2_CC_PCR_SetAuthValue: 0x183 -TPM2_CC_Policy_AC_SendSelect: 0x196 -TPM2_CC_PolicyAuthorize: 0x16a -TPM2_CC_PolicyAuthorizeNV: 0x192 -TPM2_CC_PolicyAuthValue: 0x16b -TPM2_CC_PolicyCommandCode: 0x16c -TPM2_CC_PolicyCounterTimer: 0x16d -TPM2_CC_PolicyCpHash: 0x16e -TPM2_CC_PolicyDuplicationSelect: 0x188 -TPM2_CC_PolicyGetDigest: 0x189 -TPM2_CC_PolicyLocality: 0x16f -TPM2_CC_PolicyNameHash: 0x170 -TPM2_CC_PolicyNV: 0x149 -TPM2_CC_PolicyNvWritten: 0x18f -TPM2_CC_PolicyOR: 0x171 -TPM2_CC_PolicyPassword: 0x18c -TPM2_CC_PolicyPCR: 0x17f -TPM2_CC_PolicyPhysicalPresence: 0x187 -TPM2_CC_PolicyRestart: 0x180 -TPM2_CC_PolicySecret: 0x151 -TPM2_CC_PolicySigned: 0x160 -TPM2_CC_PolicyTemplate: 0x190 -TPM2_CC_PolicyTicket: 0x172 -TPM2_CC_PP_Commands: 0x12d -TPM2_CC_Quote: 0x158 -TPM2_CC_ReadClock: 0x181 -TPM2_CC_ReadPublic: 0x173 -TPM2_CC_Rewrap: 0x152 -TPM2_CC_RSA_Decrypt: 0x159 -TPM2_CC_RSA_Encrypt: 0x174 -TPM2_CC_SelfTest: 0x143 -TPM2_CC_SequenceComplete: 0x13e -TPM2_CC_SequenceUpdate: 0x15c -TPM2_CC_SetAlgorithmSet: 0x13f -TPM2_CC_SetCommandCodeAuditStatus: 0x140 -TPM2_CC_SetPrimaryPolicy: 0x12e -TPM2_CC_Shutdown: 0x145 -TPM2_CC_Sign: 0x15d -TPM2_CC_StartAuthSession: 0x176 -TPM2_CC_Startup: 0x144 -TPM2_CC_StirRandom: 0x146 -TPM2_CC_TestParms: 0x18a -TPM2_CC_Unseal: 0x15e -TPM2_CC_Vendor_TCG_Test: 0x20000000 -TPM2_CC_VerifySignature: 0x177 -TPM2_CC_ZGen_2Phase: 0x18d

EXAMPLES

Start a policy session and extend it with a specific command like unseal. Attempts to perform other operations would fail.

Create an unseal-only policy

tpm2_startauthsession -S session.dat

tpm2_policycommandcode -S session.dat -L policy.dat TPM2_CC_Unseal

tpm2_flushcontext session.dat

Create the object with unseal-only auth policy

tpm2_createprimary -C o -c prim.ctx

tpm2_create -C prim.ctx -u sealkey.pub -r sealkey.priv -L policy.dat \
  -i- <<< "SEALED-SECRET"

Try unseal operation

tpm2_load -C prim.ctx -u sealkey.pub -r sealkey.priv -n sealkey.name \
  -c sealkey.ctx

tpm2_startauthsession --policy-session -S session.dat

tpm2_policycommandcode -S session.dat -L policy.dat TPM2_CC_Unseal

tpm2_unseal -p session:session.dat -c sealkey.ctx
SEALED-SECRET

tpm2_flushcontext session.dat

Try any other operation

echo "Encrypt Me" > plain.txt

tpm2_encryptdecrypt plain.txt -o enc.txt -c sealkey.ctx plain.txt
ERROR: Esys_EncryptDecrypt2(0x12F) - tpm:error(2.0): authValue or authPolicy is
not available for selected entity

returns

limitations

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