1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
#!/usr/bin/env python3
#
# This TCTI is designed to use with the subprocess TCTI and echo the contents
# of arg1, formatted as a hex string, as a response to a single TPM command.
#
# Example"
# ./tools/tpm2 getcap --tcti='cmd:./test/scripts/echo_tcti.py 8001000000170000000001000001000000000100000003' -i vendor
# 0000000100000003
#
import binascii
import codecs
import io
import sys
def from_bytes(b):
# python2 and 3 compat int.from_bytes(byte_order='big')
return int(codecs.encode(b, "hex"), 16)
class TPMCommand(object):
def __init__(self, data):
self._data = data
@property
def size(self, data_only=False):
x = from_bytes(self._data[2:6])
return x if data_only == False else x - 10
@property
def tag(self):
return from_bytes(self._data[0:2])
@property
def cc(self):
return from_bytes(self._data[6:10])
@property
def data(self):
return self._data[10:]
@property
def header(self):
return self._data[:10]
def read_command(stdin):
# TPM Command Header
# TAG UINT16 0:2
# SIZE UINT32 2:6
# CC UINT32 6:10
# DATA
header = stdin.read(10)
# Check for EOF
if len(header) == 0:
return None
elif len(header) < 10:
raise RuntimeError("Length of header invalid, got: %u" % len(header))
size = from_bytes(header[2:6])
data = stdin.read(size - 10)
return TPMCommand(header + data)
def write_response(data):
with io.open(sys.stdout.fileno(), "wb", closefd=False) as stdout:
bdata = binascii.unhexlify(data)
stdout.write(bdata)
stdout.flush()
def main():
if len(sys.argv) < 2:
sys.stderr.write(
"Expected one argument of a hex string to use as a TPM response buffer.\n"
)
sys.exit(1)
with io.open(sys.stdin.fileno(), "rb", closefd=False) as stdin:
c = read_command(stdin)
if c is None:
sys.exit
write_response(sys.argv[1])
if __name__ == "__main__":
main()
|
