diff options
| author | Jarkko Sakkinen | 2015-10-31 17:53:44 +0200 |
|---|---|---|
| committer | Jarkko Sakkinen | 2015-12-20 15:27:13 +0200 |
| commit | 5beb0c435bdde35a09376566b0e28f7df87c9f68 (patch) | |
| tree | 3f8c2bc84de7a77c3fed187f3bd15011e2b33e5b /drivers/char | |
| parent | 5ca4c20cfd37bac6486de040e9951b3b34755238 (diff) | |
keys, trusted: seal with a TPM2 authorization policy
TPM2 supports authorization policies, which are essentially
combinational logic statements repsenting the conditions where the data
can be unsealed based on the TPM state. This patch enables to use
authorization policies to seal trusted keys.
Two following new options have been added for trusted keys:
* 'policydigest=': provide an auth policy digest for sealing.
* 'policyhandle=': provide a policy session handle for unsealing.
If 'hash=' option is supplied after 'policydigest=' option, this
will result an error because the state of the option would become
mixed.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm2-cmd.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index d9d082206f6e..45a634016f95 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -478,12 +478,26 @@ int tpm2_seal_trusted(struct tpm_chip *chip, tpm_buf_append_u8(&buf, payload->migratable); /* public */ - tpm_buf_append_u16(&buf, 14); + if (options->policydigest) + tpm_buf_append_u16(&buf, 14 + options->digest_len); + else + tpm_buf_append_u16(&buf, 14); tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH); tpm_buf_append_u16(&buf, hash); - tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH); - tpm_buf_append_u16(&buf, 0); /* policy digest size */ + + /* policy */ + if (options->policydigest) { + tpm_buf_append_u32(&buf, 0); + tpm_buf_append_u16(&buf, options->digest_len); + tpm_buf_append(&buf, options->policydigest, + options->digest_len); + } else { + tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH); + tpm_buf_append_u16(&buf, 0); + } + + /* public parameters */ tpm_buf_append_u16(&buf, TPM2_ALG_NULL); tpm_buf_append_u16(&buf, 0); @@ -613,7 +627,9 @@ static int tpm2_unseal(struct tpm_chip *chip, return rc; tpm_buf_append_u32(&buf, blob_handle); - tpm2_buf_append_auth(&buf, TPM2_RS_PW, + tpm2_buf_append_auth(&buf, + options->policyhandle ? + options->policyhandle : TPM2_RS_PW, NULL /* nonce */, 0, 0 /* session_attributes */, options->blobauth /* hmac */, |