FazBrowse GitHub Viewer
|
Trending
|
URL:
|
Home
Tools:
[Download Repo ZIP]
[Original HTTPS Page]
cpython/Lib/hmac.py at 3.5 · python/cpython · GitHub
python
cpython
Repository navigation
Code
Issues
5k+
(5k+)
Pull requests
2.7k
(2.7k)
Actions
Projects
Security and quality
Insights
Expand file tree
Breadcrumbs
cpython
/
Lib
/
hmac.py
Copy path
More file actions
More file actions
Latest commit
History
History
History
144 lines (113 loc) · 4.94 KB
Breadcrumbs
cpython
/
Lib
/
hmac.py
Copy path
File metadata and controls
144 lines (113 loc) · 4.94 KB
Raw
Copy raw file
Download raw file
Open symbols panel
Edit and raw actions
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
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
"""HMAC (Keyed-Hashing for Message Authentication) Python module.
Implements the HMAC algorithm as described by RFC 2104.
"""
import
warnings
as
_warnings
from
_operator
import
_compare_digest
as
compare_digest
import
hashlib
as
_hashlib
trans_5C
=
bytes
((
x
^
0x5C
)
for
x
in
range
(
256
))
trans_36
=
bytes
((
x
^
0x36
)
for
x
in
range
(
256
))
# The size of the digests returned by HMAC depends on the underlying
# hashing module used. Use digest_size from the instance of HMAC instead.
digest_size
=
None
class
HMAC
:
"""RFC 2104 HMAC class. Also complies with RFC 4231.
This supports the API for Cryptographic Hash Functions (PEP 247).
"""
blocksize
=
64
# 512-bit HMAC; can be changed in subclasses.
def
__init__
(
self
,
key
,
msg
=
None
,
digestmod
=
None
):
"""Create a new HMAC object.
key: key for the keyed hash object.
msg: Initial input for the hash, if provided.
digestmod: A module supporting PEP 247. *OR*
A hashlib constructor returning a new hash object. *OR*
A hash name suitable for hashlib.new().
Defaults to hashlib.md5.
Implicit default to hashlib.md5 is deprecated and will be
removed in Python 3.6.
Note: key and msg must be a bytes or bytearray objects.
"""
if
not
isinstance
(
key
, (
bytes
,
bytearray
)):
raise
TypeError
(
"key: expected bytes or bytearray, but got %r"
%
type
(
key
).
__name__
)
if
digestmod
is
None
:
_warnings
.
warn
(
"HMAC() without an explicit digestmod argument "
"is deprecated."
,
PendingDeprecationWarning
,
2
)
digestmod
=
_hashlib
.
md5
if
callable
(
digestmod
):
self
.
digest_cons
=
digestmod
elif
isinstance
(
digestmod
,
str
):
self
.
digest_cons
=
lambda
d
=
b''
:
_hashlib
.
new
(
digestmod
,
d
)
else
:
self
.
digest_cons
=
lambda
d
=
b''
:
digestmod
.
new
(
d
)
self
.
outer
=
self
.
digest_cons
()
self
.
inner
=
self
.
digest_cons
()
self
.
digest_size
=
self
.
inner
.
digest_size
if
hasattr
(
self
.
inner
,
'block_size'
):
blocksize
=
self
.
inner
.
block_size
if
blocksize
<
16
:
_warnings
.
warn
(
'block_size of %d seems too small; using our '
'default of %d.'
%
(
blocksize
,
self
.
blocksize
),
RuntimeWarning
,
2
)
blocksize
=
self
.
blocksize
else
:
_warnings
.
warn
(
'No block_size attribute on given digest object; '
'Assuming %d.'
%
(
self
.
blocksize
),
RuntimeWarning
,
2
)
blocksize
=
self
.
blocksize
# self.blocksize is the default blocksize. self.block_size is
# effective block size as well as the public API attribute.
self
.
block_size
=
blocksize
if
len
(
key
)
>
blocksize
:
key
=
self
.
digest_cons
(
key
).
digest
()
key
=
key
+
bytes
(
blocksize
-
len
(
key
))
self
.
outer
.
update
(
key
.
translate
(
trans_5C
))
self
.
inner
.
update
(
key
.
translate
(
trans_36
))
if
msg
is
not
None
:
self
.
update
(
msg
)
@
property
def
name
(
self
):
return
"hmac-"
+
self
.
inner
.
name
def
update
(
self
,
msg
):
"""Update this hashing object with the string msg.
"""
self
.
inner
.
update
(
msg
)
def
copy
(
self
):
"""Return a separate copy of this hashing object.
An update to this copy won't affect the original object.
"""
# Call __new__ directly to avoid the expensive __init__.
other
=
self
.
__class__
.
__new__
(
self
.
__class__
)
other
.
digest_cons
=
self
.
digest_cons
other
.
digest_size
=
self
.
digest_size
other
.
inner
=
self
.
inner
.
copy
()
other
.
outer
=
self
.
outer
.
copy
()
return
other
def
_current
(
self
):
"""Return a hash object for the current state.
To be used only internally with digest() and hexdigest().
"""
h
=
self
.
outer
.
copy
()
h
.
update
(
self
.
inner
.
digest
())
return
h
def
digest
(
self
):
"""Return the hash value of this hashing object.
This returns a string containing 8-bit data. The object is
not altered in any way by this function; you can continue
updating the object after calling this function.
"""
h
=
self
.
_current
()
return
h
.
digest
()
def
hexdigest
(
self
):
"""Like digest(), but returns a string of hexadecimal digits instead.
"""
h
=
self
.
_current
()
return
h
.
hexdigest
()
def
new
(
key
,
msg
=
None
,
digestmod
=
None
):
"""Create a new hashing object and return it.
key: The starting key for the hash.
msg: if available, will immediately be hashed into the object's starting
state.
You can now feed arbitrary strings into the object using its update()
method, and can ask for the hash value at any time by calling its digest()
method.
"""
return
HMAC
(
key
,
msg
,
digestmod
)
Back
|
FazBrowse Home
|
New Git URL