• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 
2 /* MD5 module */
3 
4 /* This module provides an interface to the RSA Data Security,
5    Inc. MD5 Message-Digest Algorithm, described in RFC 1321.
6    It requires the files md5c.c and md5.h (which are slightly changed
7    from the versions in the RFC to avoid the "global.h" file.) */
8 
9 
10 /* MD5 objects */
11 
12 #include "Python.h"
13 #include "structmember.h"
14 #include "md5.h"
15 
16 typedef struct {
17     PyObject_HEAD
18     md5_state_t         md5;            /* the context holder */
19 } md5object;
20 
21 static PyTypeObject MD5type;
22 
23 #define is_md5object(v)         ((v)->ob_type == &MD5type)
24 
25 static md5object *
newmd5object(void)26 newmd5object(void)
27 {
28     md5object *md5p;
29 
30     md5p = PyObject_New(md5object, &MD5type);
31     if (md5p == NULL)
32         return NULL;
33 
34     md5_init(&md5p->md5);       /* actual initialisation */
35     return md5p;
36 }
37 
38 
39 /* MD5 methods */
40 
41 static void
md5_dealloc(md5object * md5p)42 md5_dealloc(md5object *md5p)
43 {
44     PyObject_Del(md5p);
45 }
46 
47 
48 /* MD5 methods-as-attributes */
49 
50 static PyObject *
md5_update(md5object * self,PyObject * args)51 md5_update(md5object *self, PyObject *args)
52 {
53     Py_buffer view;
54 
55     if (!PyArg_ParseTuple(args, "s*:update", &view))
56         return NULL;
57 
58     md5_append(&self->md5, (unsigned char*)view.buf,
59                Py_SAFE_DOWNCAST(view.len, Py_ssize_t, unsigned int));
60 
61     PyBuffer_Release(&view);
62     Py_RETURN_NONE;
63 }
64 
65 PyDoc_STRVAR(update_doc,
66 "update (arg)\n\
67 \n\
68 Update the md5 object with the string arg. Repeated calls are\n\
69 equivalent to a single call with the concatenation of all the\n\
70 arguments.");
71 
72 
73 static PyObject *
md5_digest(md5object * self)74 md5_digest(md5object *self)
75 {
76     md5_state_t mdContext;
77     unsigned char aDigest[16];
78 
79     /* make a temporary copy, and perform the final */
80     mdContext = self->md5;
81     md5_finish(&mdContext, aDigest);
82 
83     return PyString_FromStringAndSize((char *)aDigest, 16);
84 }
85 
86 PyDoc_STRVAR(digest_doc,
87 "digest() -> string\n\
88 \n\
89 Return the digest of the strings passed to the update() method so\n\
90 far. This is a 16-byte string which may contain non-ASCII characters,\n\
91 including null bytes.");
92 
93 
94 static PyObject *
md5_hexdigest(md5object * self)95 md5_hexdigest(md5object *self)
96 {
97     md5_state_t mdContext;
98     unsigned char digest[16];
99     unsigned char hexdigest[32];
100     int i, j;
101 
102     /* make a temporary copy, and perform the final */
103     mdContext = self->md5;
104     md5_finish(&mdContext, digest);
105 
106     /* Make hex version of the digest */
107     for(i=j=0; i<16; i++) {
108         char c;
109         c = (digest[i] >> 4) & 0xf;
110         c = (c>9) ? c+'a'-10 : c + '0';
111         hexdigest[j++] = c;
112         c = (digest[i] & 0xf);
113         c = (c>9) ? c+'a'-10 : c + '0';
114         hexdigest[j++] = c;
115     }
116     return PyString_FromStringAndSize((char*)hexdigest, 32);
117 }
118 
119 
120 PyDoc_STRVAR(hexdigest_doc,
121 "hexdigest() -> string\n\
122 \n\
123 Like digest(), but returns the digest as a string of hexadecimal digits.");
124 
125 
126 static PyObject *
md5_copy(md5object * self)127 md5_copy(md5object *self)
128 {
129     md5object *md5p;
130 
131     if ((md5p = newmd5object()) == NULL)
132         return NULL;
133 
134     md5p->md5 = self->md5;
135 
136     return (PyObject *)md5p;
137 }
138 
139 PyDoc_STRVAR(copy_doc,
140 "copy() -> md5 object\n\
141 \n\
142 Return a copy (``clone'') of the md5 object.");
143 
144 
145 static PyMethodDef md5_methods[] = {
146     {"update",    (PyCFunction)md5_update,    METH_VARARGS, update_doc},
147     {"digest",    (PyCFunction)md5_digest,    METH_NOARGS,  digest_doc},
148     {"hexdigest", (PyCFunction)md5_hexdigest, METH_NOARGS,  hexdigest_doc},
149     {"copy",      (PyCFunction)md5_copy,      METH_NOARGS,  copy_doc},
150     {NULL, NULL}                             /* sentinel */
151 };
152 
153 static PyObject *
md5_get_block_size(PyObject * self,void * closure)154 md5_get_block_size(PyObject *self, void *closure)
155 {
156     return PyInt_FromLong(64);
157 }
158 
159 static PyObject *
md5_get_digest_size(PyObject * self,void * closure)160 md5_get_digest_size(PyObject *self, void *closure)
161 {
162     return PyInt_FromLong(16);
163 }
164 
165 static PyObject *
md5_get_name(PyObject * self,void * closure)166 md5_get_name(PyObject *self, void *closure)
167 {
168     return PyString_FromStringAndSize("MD5", 3);
169 }
170 
171 static PyGetSetDef md5_getseters[] = {
172     {"digest_size",
173      (getter)md5_get_digest_size, NULL,
174      NULL,
175      NULL},
176     {"block_size",
177      (getter)md5_get_block_size, NULL,
178      NULL,
179      NULL},
180     {"name",
181      (getter)md5_get_name, NULL,
182      NULL,
183      NULL},
184     /* the old md5 and sha modules support 'digest_size' as in PEP 247.
185      * the old sha module also supported 'digestsize'.  ugh. */
186     {"digestsize",
187      (getter)md5_get_digest_size, NULL,
188      NULL,
189      NULL},
190     {NULL}  /* Sentinel */
191 };
192 
193 
194 PyDoc_STRVAR(module_doc,
195 "This module implements the interface to RSA's MD5 message digest\n\
196 algorithm (see also Internet RFC 1321). Its use is quite\n\
197 straightforward: use the new() to create an md5 object. You can now\n\
198 feed this object with arbitrary strings using the update() method, and\n\
199 at any point you can ask it for the digest (a strong kind of 128-bit\n\
200 checksum, a.k.a. ``fingerprint'') of the concatenation of the strings\n\
201 fed to it so far using the digest() method.\n\
202 \n\
203 Functions:\n\
204 \n\
205 new([arg]) -- return a new md5 object, initialized with arg if provided\n\
206 md5([arg]) -- DEPRECATED, same as new, but for compatibility\n\
207 \n\
208 Special Objects:\n\
209 \n\
210 MD5Type -- type object for md5 objects");
211 
212 PyDoc_STRVAR(md5type_doc,
213 "An md5 represents the object used to calculate the MD5 checksum of a\n\
214 string of information.\n\
215 \n\
216 Methods:\n\
217 \n\
218 update() -- updates the current digest with an additional string\n\
219 digest() -- return the current digest value\n\
220 hexdigest() -- return the current digest as a string of hexadecimal digits\n\
221 copy() -- return a copy of the current md5 object");
222 
223 static PyTypeObject MD5type = {
224     PyVarObject_HEAD_INIT(NULL, 0)
225     "_md5.md5",                   /*tp_name*/
226     sizeof(md5object),            /*tp_size*/
227     0,                            /*tp_itemsize*/
228     /* methods */
229     (destructor)md5_dealloc,  /*tp_dealloc*/
230     0,                            /*tp_print*/
231     0,                        /*tp_getattr*/
232     0,                            /*tp_setattr*/
233     0,                            /*tp_compare*/
234     0,                            /*tp_repr*/
235     0,                            /*tp_as_number*/
236     0,                        /*tp_as_sequence*/
237     0,                            /*tp_as_mapping*/
238     0,                            /*tp_hash*/
239     0,                            /*tp_call*/
240     0,                            /*tp_str*/
241     0,                            /*tp_getattro*/
242     0,                            /*tp_setattro*/
243     0,                            /*tp_as_buffer*/
244     Py_TPFLAGS_DEFAULT,           /*tp_flags*/
245     md5type_doc,                  /*tp_doc*/
246     0,                        /*tp_traverse*/
247     0,                            /*tp_clear*/
248     0,                            /*tp_richcompare*/
249     0,                            /*tp_weaklistoffset*/
250     0,                            /*tp_iter*/
251     0,                            /*tp_iternext*/
252     md5_methods,                  /*tp_methods*/
253     0,                            /*tp_members*/
254     md5_getseters,            /*tp_getset*/
255 };
256 
257 
258 /* MD5 functions */
259 
260 static PyObject *
MD5_new(PyObject * self,PyObject * args)261 MD5_new(PyObject *self, PyObject *args)
262 {
263     md5object *md5p;
264     Py_buffer view = { 0 };
265 
266     if (!PyArg_ParseTuple(args, "|s*:new", &view))
267         return NULL;
268 
269     if ((md5p = newmd5object()) == NULL) {
270         PyBuffer_Release(&view);
271         return NULL;
272     }
273 
274     if (view.len > 0) {
275         md5_append(&md5p->md5, (unsigned char*)view.buf,
276                Py_SAFE_DOWNCAST(view.len, Py_ssize_t, unsigned int));
277     }
278     PyBuffer_Release(&view);
279 
280     return (PyObject *)md5p;
281 }
282 
283 PyDoc_STRVAR(new_doc,
284 "new([arg]) -> md5 object\n\
285 \n\
286 Return a new md5 object. If arg is present, the method call update(arg)\n\
287 is made.");
288 
289 
290 /* List of functions exported by this module */
291 
292 static PyMethodDef md5_functions[] = {
293     {"new",             (PyCFunction)MD5_new, METH_VARARGS, new_doc},
294     {NULL,              NULL}   /* Sentinel */
295 };
296 
297 
298 /* Initialize this module. */
299 
300 PyMODINIT_FUNC
init_md5(void)301 init_md5(void)
302 {
303     PyObject *m, *d;
304 
305     Py_TYPE(&MD5type) = &PyType_Type;
306     if (PyType_Ready(&MD5type) < 0)
307         return;
308     m = Py_InitModule3("_md5", md5_functions, module_doc);
309     if (m == NULL)
310         return;
311     d = PyModule_GetDict(m);
312     PyDict_SetItemString(d, "MD5Type", (PyObject *)&MD5type);
313     PyModule_AddIntConstant(m, "digest_size", 16);
314     /* No need to check the error here, the caller will do that */
315 }
316