root / lib / serializer.py @ 7eda951b
History | View | Annotate | Download (4.8 kB)
1 | 8d14b30d | Iustin Pop | #
|
---|---|---|---|
2 | 8d14b30d | Iustin Pop | #
|
3 | 8d14b30d | Iustin Pop | |
4 | 8d14b30d | Iustin Pop | # Copyright (C) 2007, 2008 Google Inc.
|
5 | 8d14b30d | Iustin Pop | #
|
6 | 8d14b30d | Iustin Pop | # This program is free software; you can redistribute it and/or modify
|
7 | 8d14b30d | Iustin Pop | # it under the terms of the GNU General Public License as published by
|
8 | 8d14b30d | Iustin Pop | # the Free Software Foundation; either version 2 of the License, or
|
9 | 8d14b30d | Iustin Pop | # (at your option) any later version.
|
10 | 8d14b30d | Iustin Pop | #
|
11 | 8d14b30d | Iustin Pop | # This program is distributed in the hope that it will be useful, but
|
12 | 8d14b30d | Iustin Pop | # WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 | 8d14b30d | Iustin Pop | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 | 8d14b30d | Iustin Pop | # General Public License for more details.
|
15 | 8d14b30d | Iustin Pop | #
|
16 | 8d14b30d | Iustin Pop | # You should have received a copy of the GNU General Public License
|
17 | 8d14b30d | Iustin Pop | # along with this program; if not, write to the Free Software
|
18 | 8d14b30d | Iustin Pop | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
19 | 8d14b30d | Iustin Pop | # 02110-1301, USA.
|
20 | 8d14b30d | Iustin Pop | |
21 | 8d14b30d | Iustin Pop | """Serializer abstraction module
|
22 | 8d14b30d | Iustin Pop |
|
23 | 8d14b30d | Iustin Pop | This module introduces a simple abstraction over the serialization
|
24 | 8d14b30d | Iustin Pop | backend (currently json).
|
25 | 8d14b30d | Iustin Pop |
|
26 | 8d14b30d | Iustin Pop | """
|
27 | b459a848 | Andrea Spadaccini | # pylint: disable=C0103
|
28 | fe267188 | Iustin Pop | |
29 | fe267188 | Iustin Pop | # C0103: Invalid name, since pylint doesn't see that Dump points to a
|
30 | fe267188 | Iustin Pop | # function and not a constant
|
31 | 8d14b30d | Iustin Pop | |
32 | 8d14b30d | Iustin Pop | import re |
33 | f4a2f532 | Guido Trotter | |
34 | b76fd1bc | Michael Hanselmann | # Python 2.6 and above contain a JSON module based on simplejson. Unfortunately
|
35 | b76fd1bc | Michael Hanselmann | # the standard library version is significantly slower than the external
|
36 | b76fd1bc | Michael Hanselmann | # module. While it should be better from at least Python 3.2 on (see Python
|
37 | b76fd1bc | Michael Hanselmann | # issue 7451), for now Ganeti needs to work well with older Python versions
|
38 | b76fd1bc | Michael Hanselmann | # too.
|
39 | b76fd1bc | Michael Hanselmann | import simplejson |
40 | b76fd1bc | Michael Hanselmann | |
41 | f4a2f532 | Guido Trotter | from ganeti import errors |
42 | 615aaaba | Michael Hanselmann | from ganeti import utils |
43 | 071448fb | Michael Hanselmann | |
44 | d357f531 | Michael Hanselmann | |
45 | 8d14b30d | Iustin Pop | _JSON_INDENT = 2
|
46 | 8d14b30d | Iustin Pop | |
47 | d0c8c01d | Iustin Pop | _RE_EOLSP = re.compile("[ \t]+$", re.MULTILINE)
|
48 | 8d14b30d | Iustin Pop | |
49 | 8d14b30d | Iustin Pop | |
50 | cdeda3b6 | Michael Hanselmann | def _GetJsonDumpers(_encoder_class=simplejson.JSONEncoder): |
51 | d357f531 | Michael Hanselmann | """Returns two JSON functions to serialize data.
|
52 | d357f531 | Michael Hanselmann |
|
53 | d357f531 | Michael Hanselmann | @rtype: (callable, callable)
|
54 | d357f531 | Michael Hanselmann | @return: The function to generate a compact form of JSON and another one to
|
55 | d357f531 | Michael Hanselmann | generate a more readable, indented form of JSON (if supported)
|
56 | d357f531 | Michael Hanselmann |
|
57 | d357f531 | Michael Hanselmann | """
|
58 | 02141fb1 | Michael Hanselmann | plain_encoder = _encoder_class(sort_keys=True)
|
59 | d357f531 | Michael Hanselmann | |
60 | d357f531 | Michael Hanselmann | # Check whether the simplejson module supports indentation
|
61 | d357f531 | Michael Hanselmann | try:
|
62 | 02141fb1 | Michael Hanselmann | indent_encoder = _encoder_class(indent=_JSON_INDENT, sort_keys=True)
|
63 | d357f531 | Michael Hanselmann | except TypeError: |
64 | d357f531 | Michael Hanselmann | # Indentation not supported
|
65 | 02141fb1 | Michael Hanselmann | indent_encoder = plain_encoder |
66 | d357f531 | Michael Hanselmann | |
67 | 02141fb1 | Michael Hanselmann | return (plain_encoder.encode, indent_encoder.encode)
|
68 | d357f531 | Michael Hanselmann | |
69 | d357f531 | Michael Hanselmann | |
70 | d357f531 | Michael Hanselmann | (_DumpJson, _DumpJsonIndent) = _GetJsonDumpers() |
71 | d357f531 | Michael Hanselmann | |
72 | d357f531 | Michael Hanselmann | |
73 | 071448fb | Michael Hanselmann | def DumpJson(data, indent=True): |
74 | 8d14b30d | Iustin Pop | """Serialize a given object.
|
75 | 8d14b30d | Iustin Pop |
|
76 | c41eea6e | Iustin Pop | @param data: the data to serialize
|
77 | c41eea6e | Iustin Pop | @param indent: whether to indent output (depends on simplejson version)
|
78 | c41eea6e | Iustin Pop |
|
79 | c41eea6e | Iustin Pop | @return: the string representation of data
|
80 | 071448fb | Michael Hanselmann |
|
81 | 8d14b30d | Iustin Pop | """
|
82 | d357f531 | Michael Hanselmann | if indent:
|
83 | d357f531 | Michael Hanselmann | fn = _DumpJsonIndent |
84 | 8d14b30d | Iustin Pop | else:
|
85 | d357f531 | Michael Hanselmann | fn = _DumpJson |
86 | 071448fb | Michael Hanselmann | |
87 | d357f531 | Michael Hanselmann | txt = _RE_EOLSP.sub("", fn(data))
|
88 | d0c8c01d | Iustin Pop | if not txt.endswith("\n"): |
89 | d0c8c01d | Iustin Pop | txt += "\n"
|
90 | d357f531 | Michael Hanselmann | |
91 | 8d14b30d | Iustin Pop | return txt
|
92 | 8d14b30d | Iustin Pop | |
93 | 8d14b30d | Iustin Pop | |
94 | 228538cf | Michael Hanselmann | def LoadJson(txt): |
95 | 8d14b30d | Iustin Pop | """Unserialize data from a string.
|
96 | 8d14b30d | Iustin Pop |
|
97 | c41eea6e | Iustin Pop | @param txt: the json-encoded form
|
98 | c41eea6e | Iustin Pop |
|
99 | c41eea6e | Iustin Pop | @return: the original data
|
100 | c41eea6e | Iustin Pop |
|
101 | 8d14b30d | Iustin Pop | """
|
102 | cdeda3b6 | Michael Hanselmann | return simplejson.loads(txt)
|
103 | 228538cf | Michael Hanselmann | |
104 | 228538cf | Michael Hanselmann | |
105 | 72ca1dcb | Balazs Lecz | def DumpSignedJson(data, key, salt=None, key_selector=None): |
106 | f4a2f532 | Guido Trotter | """Serialize a given object and authenticate it.
|
107 | f4a2f532 | Guido Trotter |
|
108 | f4a2f532 | Guido Trotter | @param data: the data to serialize
|
109 | f4a2f532 | Guido Trotter | @param key: shared hmac key
|
110 | 72ca1dcb | Balazs Lecz | @param key_selector: name/id that identifies the key (in case there are
|
111 | 72ca1dcb | Balazs Lecz | multiple keys in use, e.g. in a multi-cluster environment)
|
112 | f4a2f532 | Guido Trotter | @return: the string representation of data signed by the hmac key
|
113 | f4a2f532 | Guido Trotter |
|
114 | f4a2f532 | Guido Trotter | """
|
115 | f4a2f532 | Guido Trotter | txt = DumpJson(data, indent=False)
|
116 | f4a2f532 | Guido Trotter | if salt is None: |
117 | d0c8c01d | Iustin Pop | salt = ""
|
118 | f4a2f532 | Guido Trotter | signed_dict = { |
119 | d0c8c01d | Iustin Pop | "msg": txt,
|
120 | d0c8c01d | Iustin Pop | "salt": salt,
|
121 | 3718bf6d | Michael Hanselmann | } |
122 | 3718bf6d | Michael Hanselmann | |
123 | 72ca1dcb | Balazs Lecz | if key_selector:
|
124 | 72ca1dcb | Balazs Lecz | signed_dict["key_selector"] = key_selector
|
125 | 72ca1dcb | Balazs Lecz | else:
|
126 | 3718bf6d | Michael Hanselmann | key_selector = ""
|
127 | 3718bf6d | Michael Hanselmann | |
128 | 3718bf6d | Michael Hanselmann | signed_dict["hmac"] = utils.Sha1Hmac(key, txt, salt=salt + key_selector)
|
129 | 72ca1dcb | Balazs Lecz | |
130 | 40765aa0 | Guido Trotter | return DumpJson(signed_dict, indent=False) |
131 | f4a2f532 | Guido Trotter | |
132 | f4a2f532 | Guido Trotter | |
133 | 4e9dac14 | Guido Trotter | def LoadSignedJson(txt, key): |
134 | f4a2f532 | Guido Trotter | """Verify that a given message was signed with the given key, and load it.
|
135 | f4a2f532 | Guido Trotter |
|
136 | f4a2f532 | Guido Trotter | @param txt: json-encoded hmac-signed message
|
137 | 72ca1dcb | Balazs Lecz | @param key: the shared hmac key or a callable taking one argument (the key
|
138 | 72ca1dcb | Balazs Lecz | selector), which returns the hmac key belonging to the key selector.
|
139 | 72ca1dcb | Balazs Lecz | Typical usage is to pass a reference to the get method of a dict.
|
140 | f4a2f532 | Guido Trotter | @rtype: tuple of original data, string
|
141 | 4e9dac14 | Guido Trotter | @return: original data, salt
|
142 | f4a2f532 | Guido Trotter | @raises errors.SignatureError: if the message signature doesn't verify
|
143 | f4a2f532 | Guido Trotter |
|
144 | f4a2f532 | Guido Trotter | """
|
145 | f4a2f532 | Guido Trotter | signed_dict = LoadJson(txt) |
146 | f4a2f532 | Guido Trotter | if not isinstance(signed_dict, dict): |
147 | d0c8c01d | Iustin Pop | raise errors.SignatureError("Invalid external message") |
148 | f4a2f532 | Guido Trotter | try:
|
149 | d0c8c01d | Iustin Pop | msg = signed_dict["msg"]
|
150 | d0c8c01d | Iustin Pop | salt = signed_dict["salt"]
|
151 | d0c8c01d | Iustin Pop | hmac_sign = signed_dict["hmac"]
|
152 | f4a2f532 | Guido Trotter | except KeyError: |
153 | d0c8c01d | Iustin Pop | raise errors.SignatureError("Invalid external message") |
154 | f4a2f532 | Guido Trotter | |
155 | 72ca1dcb | Balazs Lecz | if callable(key): |
156 | b459a848 | Andrea Spadaccini | # pylint: disable=E1103
|
157 | 72ca1dcb | Balazs Lecz | key_selector = signed_dict.get("key_selector", None) |
158 | 72ca1dcb | Balazs Lecz | hmac_key = key(key_selector) |
159 | 72ca1dcb | Balazs Lecz | if not hmac_key: |
160 | 72ca1dcb | Balazs Lecz | raise errors.SignatureError("No key with key selector '%s' found" % |
161 | 72ca1dcb | Balazs Lecz | key_selector) |
162 | 72ca1dcb | Balazs Lecz | else:
|
163 | 72ca1dcb | Balazs Lecz | key_selector = ""
|
164 | 72ca1dcb | Balazs Lecz | hmac_key = key |
165 | 72ca1dcb | Balazs Lecz | |
166 | 3718bf6d | Michael Hanselmann | if not utils.VerifySha1Hmac(hmac_key, msg, hmac_sign, |
167 | 3718bf6d | Michael Hanselmann | salt=salt + key_selector): |
168 | d0c8c01d | Iustin Pop | raise errors.SignatureError("Invalid Signature") |
169 | f4a2f532 | Guido Trotter | |
170 | 4e9dac14 | Guido Trotter | return LoadJson(msg), salt
|
171 | f4a2f532 | Guido Trotter | |
172 | f4a2f532 | Guido Trotter | |
173 | 228538cf | Michael Hanselmann | Dump = DumpJson |
174 | 228538cf | Michael Hanselmann | Load = LoadJson |
175 | f4a2f532 | Guido Trotter | DumpSigned = DumpSignedJson |
176 | f4a2f532 | Guido Trotter | LoadSigned = LoadSignedJson |