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Extend functionalities for different TPM classes #6

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95 changes: 90 additions & 5 deletions pytss/__init__.py
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Original file line number Diff line number Diff line change
Expand Up @@ -219,8 +219,20 @@ def sign(self, key):
csig_size = ffi.new("UINT32*")
csig_data = ffi.new("BYTE**")
tss_lib.Tspi_Hash_Sign(self.get_handle(), key.get_handle(), csig_size, csig_data)
return ffi.buffer(csig_data[0], csig_size[0])
ret = bytearray(csig_data[0][0:csig_size[0]])
tss_lib.Tspi_Context_FreeMemory(self.context, csig_data[0])
return ret

def get_digest(self):
"""
Get the hash value of this object
"""
digest_len = ffi.new('UINT32 *')
digest = ffi.new('BYTE **')
tss_lib.Tspi_Hash_GetHashValue(self.get_handle(), digest_len, digest)
ret = bytearray(digest[0][0:digest_len[0]])
tss_lib.Tspi_Context_FreeMemory(self.context, digest[0])
return ret

class TspiKey(TspiObject):
def __init__(self, context, flags, handle=None):
Expand Down Expand Up @@ -264,6 +276,12 @@ def get_pubkeyblob(self):
return self.get_attribute_data(tss_lib.TSS_TSPATTRIB_KEY_BLOB,
tss_lib.TSS_TSPATTRIB_KEYBLOB_PUBLIC_KEY)

def create_key(self, parentKey, pcr):
"""
Create this key given the parent key
"""
tss_lib.Tspi_Key_CreateKey(self.get_handle(), parentKey.get_handle(), pcr)

def get_pubkey(self):
"""
Obtain the public part of the key
Expand All @@ -273,6 +291,14 @@ def get_pubkey(self):
return self.get_attribute_data(tss_lib.TSS_TSPATTRIB_RSAKEY_INFO,
tss_lib.TSS_TSPATTRIB_KEYINFO_RSA_MODULUS)

def get_pubkey_exponent(self):
"""
Obtain the public exponent part of the key

:returns: a bytearray containing the exponent of the key
"""
return self.get_attribute_data(tss_lib.TSS_TSPATTRIB_RSAKEY_INFO,
tss_lib.TSS_TSPATTRIB_KEYINFO_RSA_EXPONENT)

def seal(self, data, pcrs=None):
"""
Expand All @@ -294,12 +320,11 @@ def seal(self, data, pcrs=None):
else:
pcr_composite = 0

cdata = ffi.new('BYTE[]', len(data))
for i in range(len(data)):
cdata[i] = data[i]
clen = ffi.cast('UINT32', len(data))
cdata = _c_byte_array(data)

tss_lib.Tspi_Data_Seal(encdata.get_handle(), self.get_handle(),
len(data), cdata, pcr_composite)
clen, cdata, pcr_composite)
blob = encdata.get_attribute_data(tss_lib.TSS_TSPATTRIB_ENCDATA_BLOB,
tss_lib.TSS_TSPATTRIB_ENCDATABLOB_BLOB)
return bytearray(blob)
Expand Down Expand Up @@ -452,6 +477,35 @@ def take_ownership(self, srk):
"""
tss_lib.Tspi_TPM_TakeOwnership(self.get_handle(), srk.get_handle(), 0)

def get_pub_srk_key(self):
"""
Get the public portion of the SRK

:returns: public portion of SRK and its length
"""
buf = ffi.new('BYTE **')
buf_len = ffi.new('UINT32 *')
tss_lib.Tspi_TPM_OwnerGetSRKPubKey(self.get_handle(), buf_len, buf)
srk_len = buf_len[0]
srk = bytearray(buf[0][0:srk_len])
tss_lib.Tspi_Context_FreeMemory(self.context, buf[0])
return srk, srk_len

def get_pcr(self, pcr):
"""
Get the value of the PCR

:param pcr: The PCR to read

:returns: PCR value
"""
buf = ffi.new('BYTE **')
buf_len = ffi.new('UINT32 *')
tss_lib.Tspi_TPM_PcrRead(self.get_handle(), pcr, buf_len, buf)
pcrs = bytearray(buf[0][0:buf_len[0]])
tss_lib.Tspi_Context_FreeMemory(self.context, buf[0])
return pcrs

def extend_pcr(self, pcr, data, event):
"""
Extend a PCR
Expand All @@ -474,6 +528,22 @@ def extend_pcr(self, pcr, data, event):
tss_lib.Tspi_Context_FreeMemory(self.context, blob[0])
return ret

def get_random(self, length):
"""
Generate random number

:param length: Length of the generated random number

:returns: A bytearray containing the random number
"""
random_len = ffi.cast('UINT32', length)
random_num = ffi.new('BYTE **')

tss_lib.Tspi_TPM_GetRandom(self.get_handle(), random_len, random_num)
ret = bytearray(random_num[0][0:length])
tss_lib.Tspi_Context_FreeMemory(self.context, random_num[0])
return ret

class TspiContext():
def __init__(self):
self.context = ffi.new('TSS_HCONTEXT *')
Expand Down Expand Up @@ -583,6 +653,21 @@ def get_tpm_object(self):
"""Returns the TspiTPM associated with this context"""
return self.tpm

def register_key(self, key, key_storage_type, key_uuid, parent_storage_type, parent_uuid):
"""
Register this key given the parent key

:param key: The key to store in persistent storage
:param key_storage_type: Storage type of this key
:param key_uuid: The UUID used to identify this key
:param parent_storage_type: Storage type of the parent key
:param parent_uuid: The UUID used to identify the parent key

"""
tss_key_uuid = uuid_to_tss_uuid(key_uuid)
tss_parent_uuid = uuid_to_tss_uuid(parent_uuid)
tss_lib.Tspi_Context_RegisterKey(self.context, key.get_handle(), key_storage_type, tss_key_uuid, parent_storage_type, tss_parent_uuid)


def _c_byte_array(data):
"""
Expand Down