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tpm2.py 18.94 KiB
# SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
import hashlib
import os
import socket
import struct
import sys
import unittest
from fcntl import ioctl
TPM2_ST_NO_SESSIONS = 0x8001
TPM2_ST_SESSIONS = 0x8002
TPM2_CC_FIRST = 0x01FF
TPM2_CC_CREATE_PRIMARY = 0x0131
TPM2_CC_DICTIONARY_ATTACK_LOCK_RESET = 0x0139
TPM2_CC_CREATE = 0x0153
TPM2_CC_LOAD = 0x0157
TPM2_CC_UNSEAL = 0x015E
TPM2_CC_FLUSH_CONTEXT = 0x0165
TPM2_CC_START_AUTH_SESSION = 0x0176
TPM2_CC_GET_CAPABILITY = 0x017A
TPM2_CC_PCR_READ = 0x017E
TPM2_CC_POLICY_PCR = 0x017F
TPM2_CC_PCR_EXTEND = 0x0182
TPM2_CC_POLICY_PASSWORD = 0x018C
TPM2_CC_POLICY_GET_DIGEST = 0x0189
TPM2_SE_POLICY = 0x01
TPM2_SE_TRIAL = 0x03
TPM2_ALG_RSA = 0x0001
TPM2_ALG_SHA1 = 0x0004
TPM2_ALG_AES = 0x0006
TPM2_ALG_KEYEDHASH = 0x0008
TPM2_ALG_SHA256 = 0x000B
TPM2_ALG_NULL = 0x0010
TPM2_ALG_CBC = 0x0042
TPM2_ALG_CFB = 0x0043
TPM2_RH_OWNER = 0x40000001
TPM2_RH_NULL = 0x40000007
TPM2_RH_LOCKOUT = 0x4000000A
TPM2_RS_PW = 0x40000009
TPM2_RC_SIZE = 0x01D5
TPM2_RC_AUTH_FAIL = 0x098E
TPM2_RC_POLICY_FAIL = 0x099D
TPM2_RC_COMMAND_CODE = 0x0143
TSS2_RC_LAYER_SHIFT = 16
TSS2_RESMGR_TPM_RC_LAYER = (11 << TSS2_RC_LAYER_SHIFT)
TPM2_CAP_HANDLES = 0x00000001
TPM2_CAP_COMMANDS = 0x00000002
TPM2_CAP_TPM_PROPERTIES = 0x00000006
TPM2_PT_FIXED = 0x100
TPM2_PT_TOTAL_COMMANDS = TPM2_PT_FIXED + 41
HR_SHIFT = 24
HR_LOADED_SESSION = 0x02000000
HR_TRANSIENT = 0x80000000
SHA1_DIGEST_SIZE = 20
SHA256_DIGEST_SIZE = 32
TPM2_VER0_ERRORS = {
0x000: "TPM_RC_SUCCESS",
0x030: "TPM_RC_BAD_TAG",
}
TPM2_VER1_ERRORS = {
0x000: "TPM_RC_FAILURE",
0x001: "TPM_RC_FAILURE",
0x003: "TPM_RC_SEQUENCE",
0x00B: "TPM_RC_PRIVATE",
0x019: "TPM_RC_HMAC",
0x020: "TPM_RC_DISABLED",
0x021: "TPM_RC_EXCLUSIVE",
0x024: "TPM_RC_AUTH_TYPE",
0x025: "TPM_RC_AUTH_MISSING",
0x026: "TPM_RC_POLICY",
0x027: "TPM_RC_PCR",
0x028: "TPM_RC_PCR_CHANGED",
0x02D: "TPM_RC_UPGRADE",
0x02E: "TPM_RC_TOO_MANY_CONTEXTS",
0x02F: "TPM_RC_AUTH_UNAVAILABLE",
0x030: "TPM_RC_REBOOT",
0x031: "TPM_RC_UNBALANCED",
0x042: "TPM_RC_COMMAND_SIZE",
0x043: "TPM_RC_COMMAND_CODE",
0x044: "TPM_RC_AUTHSIZE",
0x045: "TPM_RC_AUTH_CONTEXT",
0x046: "TPM_RC_NV_RANGE",
0x047: "TPM_RC_NV_SIZE",
0x048: "TPM_RC_NV_LOCKED",
0x049: "TPM_RC_NV_AUTHORIZATION",
0x04A: "TPM_RC_NV_UNINITIALIZED",
0x04B: "TPM_RC_NV_SPACE",
0x04C: "TPM_RC_NV_DEFINED",
0x050: "TPM_RC_BAD_CONTEXT",
0x051: "TPM_RC_CPHASH",
0x052: "TPM_RC_PARENT",
0x053: "TPM_RC_NEEDS_TEST",
0x054: "TPM_RC_NO_RESULT",
0x055: "TPM_RC_SENSITIVE",
0x07F: "RC_MAX_FM0",
}
TPM2_FMT1_ERRORS = {
0x001: "TPM_RC_ASYMMETRIC",
0x002: "TPM_RC_ATTRIBUTES",
0x003: "TPM_RC_HASH",
0x004: "TPM_RC_VALUE",
0x005: "TPM_RC_HIERARCHY",
0x007: "TPM_RC_KEY_SIZE",
0x008: "TPM_RC_MGF",
0x009: "TPM_RC_MODE",
0x00A: "TPM_RC_TYPE",
0x00B: "TPM_RC_HANDLE",
0x00C: "TPM_RC_KDF",
0x00D: "TPM_RC_RANGE",
0x00E: "TPM_RC_AUTH_FAIL",
0x00F: "TPM_RC_NONCE",
0x010: "TPM_RC_PP",
0x012: "TPM_RC_SCHEME",
0x015: "TPM_RC_SIZE",
0x016: "TPM_RC_SYMMETRIC",
0x017: "TPM_RC_TAG",
0x018: "TPM_RC_SELECTOR",
0x01A: "TPM_RC_INSUFFICIENT",
0x01B: "TPM_RC_SIGNATURE",
0x01C: "TPM_RC_KEY",
0x01D: "TPM_RC_POLICY_FAIL",
0x01F: "TPM_RC_INTEGRITY",
0x020: "TPM_RC_TICKET",
0x021: "TPM_RC_RESERVED_BITS",
0x022: "TPM_RC_BAD_AUTH",
0x023: "TPM_RC_EXPIRED",
0x024: "TPM_RC_POLICY_CC",
0x025: "TPM_RC_BINDING",
0x026: "TPM_RC_CURVE",
0x027: "TPM_RC_ECC_POINT",
}
TPM2_WARN_ERRORS = {
0x001: "TPM_RC_CONTEXT_GAP",
0x002: "TPM_RC_OBJECT_MEMORY",
0x003: "TPM_RC_SESSION_MEMORY",
0x004: "TPM_RC_MEMORY",
0x005: "TPM_RC_SESSION_HANDLES",
0x006: "TPM_RC_OBJECT_HANDLES",
0x007: "TPM_RC_LOCALITY",
0x008: "TPM_RC_YIELDED",
0x009: "TPM_RC_CANCELED",
0x00A: "TPM_RC_TESTING",
0x010: "TPM_RC_REFERENCE_H0",
0x011: "TPM_RC_REFERENCE_H1",
0x012: "TPM_RC_REFERENCE_H2",
0x013: "TPM_RC_REFERENCE_H3",
0x014: "TPM_RC_REFERENCE_H4",
0x015: "TPM_RC_REFERENCE_H5",
0x016: "TPM_RC_REFERENCE_H6",
0x018: "TPM_RC_REFERENCE_S0",
0x019: "TPM_RC_REFERENCE_S1",
0x01A: "TPM_RC_REFERENCE_S2",
0x01B: "TPM_RC_REFERENCE_S3",
0x01C: "TPM_RC_REFERENCE_S4",
0x01D: "TPM_RC_REFERENCE_S5",
0x01E: "TPM_RC_REFERENCE_S6",
0x020: "TPM_RC_NV_RATE",
0x021: "TPM_RC_LOCKOUT",
0x022: "TPM_RC_RETRY",
0x023: "TPM_RC_NV_UNAVAILABLE",
0x7F: "TPM_RC_NOT_USED",
}
RC_VER1 = 0x100
RC_FMT1 = 0x080
RC_WARN = 0x900
ALG_DIGEST_SIZE_MAP = {
TPM2_ALG_SHA1: SHA1_DIGEST_SIZE,
TPM2_ALG_SHA256: SHA256_DIGEST_SIZE,
}
ALG_HASH_FUNCTION_MAP = {
TPM2_ALG_SHA1: hashlib.sha1,
TPM2_ALG_SHA256: hashlib.sha256
}
NAME_ALG_MAP = {
"sha1": TPM2_ALG_SHA1,
"sha256": TPM2_ALG_SHA256,
}
class UnknownAlgorithmIdError(Exception):
def __init__(self, alg):
self.alg = alg
def __str__(self):
return '0x%0x' % (alg)
class UnknownAlgorithmNameError(Exception):
def __init__(self, name):
self.name = name
def __str__(self):
return name
class UnknownPCRBankError(Exception):
def __init__(self, alg):
self.alg = alg
def __str__(self):
return '0x%0x' % (alg)
class ProtocolError(Exception):
def __init__(self, cc, rc):
self.cc = cc
self.rc = rc
if (rc & RC_FMT1) == RC_FMT1:
self.name = TPM2_FMT1_ERRORS.get(rc & 0x3f, "TPM_RC_UNKNOWN")
elif (rc & RC_WARN) == RC_WARN:
self.name = TPM2_WARN_ERRORS.get(rc & 0x7f, "TPM_RC_UNKNOWN")
elif (rc & RC_VER1) == RC_VER1:
self.name = TPM2_VER1_ERRORS.get(rc & 0x7f, "TPM_RC_UNKNOWN")
else:
self.name = TPM2_VER0_ERRORS.get(rc & 0x7f, "TPM_RC_UNKNOWN")
def __str__(self):
if self.cc:
return '%s: cc=0x%08x, rc=0x%08x' % (self.name, self.cc, self.rc)
else:
return '%s: rc=0x%08x' % (self.name, self.rc)
class AuthCommand(object):
"""TPMS_AUTH_COMMAND"""
def __init__(self, session_handle=TPM2_RS_PW, nonce='', session_attributes=0,
hmac=''):
self.session_handle = session_handle
self.nonce = nonce
self.session_attributes = session_attributes
self.hmac = hmac
def __str__(self):
fmt = '>I H%us B H%us' % (len(self.nonce), len(self.hmac))
return struct.pack(fmt, self.session_handle, len(self.nonce),
self.nonce, self.session_attributes, len(self.hmac),
self.hmac)
def __len__(self):
fmt = '>I H%us B H%us' % (len(self.nonce), len(self.hmac))
return struct.calcsize(fmt)
class SensitiveCreate(object):
"""TPMS_SENSITIVE_CREATE"""
def __init__(self, user_auth='', data=''):
self.user_auth = user_auth
self.data = data
def __str__(self):
fmt = '>H%us H%us' % (len(self.user_auth), len(self.data))
return struct.pack(fmt, len(self.user_auth), self.user_auth,
len(self.data), self.data)
def __len__(self):
fmt = '>H%us H%us' % (len(self.user_auth), len(self.data))
return struct.calcsize(fmt)
class Public(object):
"""TPMT_PUBLIC"""
FIXED_TPM = (1 << 1)
FIXED_PARENT = (1 << 4)
SENSITIVE_DATA_ORIGIN = (1 << 5)
USER_WITH_AUTH = (1 << 6)
RESTRICTED = (1 << 16)
DECRYPT = (1 << 17)
def __fmt(self):
return '>HHIH%us%usH%us' % \
(len(self.auth_policy), len(self.parameters), len(self.unique))
def __init__(self, object_type, name_alg, object_attributes, auth_policy='',
parameters='', unique=''):
self.object_type = object_type
self.name_alg = name_alg
self.object_attributes = object_attributes
self.auth_policy = auth_policy
self.parameters = parameters
self.unique = unique
def __str__(self):
return struct.pack(self.__fmt(),
self.object_type,
self.name_alg,
self.object_attributes,
len(self.auth_policy),
self.auth_policy,
self.parameters,
len(self.unique),
self.unique)
def __len__(self):
return struct.calcsize(self.__fmt())
def get_digest_size(alg):
ds = ALG_DIGEST_SIZE_MAP.get(alg)
if not ds:
raise UnknownAlgorithmIdError(alg)
return ds
def get_hash_function(alg):
f = ALG_HASH_FUNCTION_MAP.get(alg)
if not f:
raise UnknownAlgorithmIdError(alg)
return f
def get_algorithm(name):
alg = NAME_ALG_MAP.get(name)
if not alg:
raise UnknownAlgorithmNameError(name)
return alg
def hex_dump(d):
d = [format(ord(x), '02x') for x in d]
d = [d[i: i + 16] for i in xrange(0, len(d), 16)]
d = [' '.join(x) for x in d]
d = os.linesep.join(d)
return d
class Client:
FLAG_DEBUG = 0x01
FLAG_SPACE = 0x02
TPM_IOC_NEW_SPACE = 0xa200
def __init__(self, flags = 0):
self.flags = flags
if (self.flags & Client.FLAG_SPACE) == 0:
self.tpm = open('/dev/tpm0', 'r+b')
else:
self.tpm = open('/dev/tpmrm0', 'r+b')
def close(self):
self.tpm.close()
def send_cmd(self, cmd):
self.tpm.write(cmd)
rsp = self.tpm.read()
if (self.flags & Client.FLAG_DEBUG) != 0:
sys.stderr.write('cmd' + os.linesep)
sys.stderr.write(hex_dump(cmd) + os.linesep)
sys.stderr.write('rsp' + os.linesep)
sys.stderr.write(hex_dump(rsp) + os.linesep)
rc = struct.unpack('>I', rsp[6:10])[0]
if rc != 0:
cc = struct.unpack('>I', cmd[6:10])[0]
raise ProtocolError(cc, rc)
return rsp
def read_pcr(self, i, bank_alg = TPM2_ALG_SHA1):
pcrsel_len = max((i >> 3) + 1, 3)
pcrsel = [0] * pcrsel_len
pcrsel[i >> 3] = 1 << (i & 7)
pcrsel = ''.join(map(chr, pcrsel))
fmt = '>HII IHB%us' % (pcrsel_len)
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_PCR_READ,
1,
bank_alg,
pcrsel_len, pcrsel)
rsp = self.send_cmd(cmd)
pcr_update_cnt, pcr_select_cnt = struct.unpack('>II', rsp[10:18])
assert pcr_select_cnt == 1
rsp = rsp[18:]
alg2, pcrsel_len2 = struct.unpack('>HB', rsp[:3])
assert bank_alg == alg2 and pcrsel_len == pcrsel_len2
rsp = rsp[3 + pcrsel_len:]
digest_cnt = struct.unpack('>I', rsp[:4])[0]
if digest_cnt == 0:
return None
rsp = rsp[6:]
return rsp
def extend_pcr(self, i, dig, bank_alg = TPM2_ALG_SHA1):
ds = get_digest_size(bank_alg)
assert(ds == len(dig))
auth_cmd = AuthCommand()
fmt = '>HII I I%us IH%us' % (len(auth_cmd), ds)
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_PCR_EXTEND,
i,
len(auth_cmd),
str(auth_cmd),
1, bank_alg, dig)
self.send_cmd(cmd)
def start_auth_session(self, session_type, name_alg = TPM2_ALG_SHA1):
fmt = '>HII IIH16sHBHH'
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_START_AUTH_SESSION,
TPM2_RH_NULL,
TPM2_RH_NULL,
16,
'\0' * 16,
0,
session_type,
TPM2_ALG_NULL,
name_alg)
return struct.unpack('>I', self.send_cmd(cmd)[10:14])[0]
def __calc_pcr_digest(self, pcrs, bank_alg = TPM2_ALG_SHA1,
digest_alg = TPM2_ALG_SHA1):
x = []
f = get_hash_function(digest_alg)
for i in pcrs:
pcr = self.read_pcr(i, bank_alg)
if pcr == None:
return None
x += pcr
return f(bytearray(x)).digest()
def policy_pcr(self, handle, pcrs, bank_alg = TPM2_ALG_SHA1,
name_alg = TPM2_ALG_SHA1):
ds = get_digest_size(name_alg)
dig = self.__calc_pcr_digest(pcrs, bank_alg, name_alg)
if not dig:
raise UnknownPCRBankError(bank_alg)
pcrsel_len = max((max(pcrs) >> 3) + 1, 3)
pcrsel = [0] * pcrsel_len
for i in pcrs:
pcrsel[i >> 3] |= 1 << (i & 7)
pcrsel = ''.join(map(chr, pcrsel))
fmt = '>HII IH%usIHB3s' % ds
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_POLICY_PCR,
handle,
len(dig), str(dig),
1,
bank_alg,
pcrsel_len, pcrsel)
self.send_cmd(cmd)
def policy_password(self, handle):
fmt = '>HII I'
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_POLICY_PASSWORD,
handle)
self.send_cmd(cmd)
def get_policy_digest(self, handle):
fmt = '>HII I'
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_POLICY_GET_DIGEST,
handle)
return self.send_cmd(cmd)[12:]
def flush_context(self, handle):
fmt = '>HIII'
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_FLUSH_CONTEXT,
handle)
self.send_cmd(cmd)
def create_root_key(self, auth_value = ''):
attributes = \
Public.FIXED_TPM | \
Public.FIXED_PARENT | \
Public.SENSITIVE_DATA_ORIGIN | \
Public.USER_WITH_AUTH | \
Public.RESTRICTED | \
Public.DECRYPT
auth_cmd = AuthCommand()
sensitive = SensitiveCreate(user_auth=auth_value)
public_parms = struct.pack(
'>HHHHHI',
TPM2_ALG_AES,
128,
TPM2_ALG_CFB,
TPM2_ALG_NULL,
2048,
0)
public = Public(
object_type=TPM2_ALG_RSA,
name_alg=TPM2_ALG_SHA1,
object_attributes=attributes,
parameters=public_parms)
fmt = '>HIII I%us H%us H%us HI' % \
(len(auth_cmd), len(sensitive), len(public))
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_CREATE_PRIMARY,
TPM2_RH_OWNER,
len(auth_cmd),
str(auth_cmd),
len(sensitive),
str(sensitive),
len(public),
str(public),
0, 0)
return struct.unpack('>I', self.send_cmd(cmd)[10:14])[0]
def seal(self, parent_key, data, auth_value, policy_dig,
name_alg = TPM2_ALG_SHA1):
ds = get_digest_size(name_alg)
assert(not policy_dig or ds == len(policy_dig))
attributes = 0
if not policy_dig:
attributes |= Public.USER_WITH_AUTH
policy_dig = ''
auth_cmd = AuthCommand()
sensitive = SensitiveCreate(user_auth=auth_value, data=data)
public = Public(
object_type=TPM2_ALG_KEYEDHASH,
name_alg=name_alg,
object_attributes=attributes,
auth_policy=policy_dig,
parameters=struct.pack('>H', TPM2_ALG_NULL))
fmt = '>HIII I%us H%us H%us HI' % \
(len(auth_cmd), len(sensitive), len(public))
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_CREATE,
parent_key,
len(auth_cmd),
str(auth_cmd),
len(sensitive),
str(sensitive),
len(public),
str(public),
0, 0)
rsp = self.send_cmd(cmd)
return rsp[14:]
def unseal(self, parent_key, blob, auth_value, policy_handle):
private_len = struct.unpack('>H', blob[0:2])[0]
public_start = private_len + 2
public_len = struct.unpack('>H', blob[public_start:public_start + 2])[0]
blob = blob[:private_len + public_len + 4]
auth_cmd = AuthCommand()
fmt = '>HII I I%us %us' % (len(auth_cmd), len(blob))
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_LOAD,
parent_key,
len(auth_cmd),
str(auth_cmd),
blob)
data_handle = struct.unpack('>I', self.send_cmd(cmd)[10:14])[0]
if policy_handle:
auth_cmd = AuthCommand(session_handle=policy_handle, hmac=auth_value)
else:
auth_cmd = AuthCommand(hmac=auth_value)
fmt = '>HII I I%us' % (len(auth_cmd))
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_UNSEAL,
data_handle,
len(auth_cmd),
str(auth_cmd))
try:
rsp = self.send_cmd(cmd)
finally:
self.flush_context(data_handle)
data_len = struct.unpack('>I', rsp[10:14])[0] - 2
return rsp[16:16 + data_len]
def reset_da_lock(self):
auth_cmd = AuthCommand()
fmt = '>HII I I%us' % (len(auth_cmd))
cmd = struct.pack(
fmt,
TPM2_ST_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_DICTIONARY_ATTACK_LOCK_RESET,
TPM2_RH_LOCKOUT,
len(auth_cmd),
str(auth_cmd))
self.send_cmd(cmd)
def __get_cap_cnt(self, cap, pt, cnt):
handles = []
fmt = '>HII III'
cmd = struct.pack(fmt,
TPM2_ST_NO_SESSIONS,
struct.calcsize(fmt),
TPM2_CC_GET_CAPABILITY,
cap, pt, cnt)
rsp = self.send_cmd(cmd)[10:]
more_data, cap, cnt = struct.unpack('>BII', rsp[:9])
rsp = rsp[9:]
for i in xrange(0, cnt):
handle = struct.unpack('>I', rsp[:4])[0]
handles.append(handle)
rsp = rsp[4:]
return handles, more_data
def get_cap(self, cap, pt):
handles = []
more_data = True
while more_data:
next_handles, more_data = self.__get_cap_cnt(cap, pt, 1)
handles += next_handles
pt += 1
return handles