Modules/md5module.c

   1 /***********************************************************
   2 Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
   3 The Netherlands.
   4
   5                         All Rights Reserved
   6
   7 Permission to use, copy, modify, and distribute this software and its
   8 documentation for any purpose and without fee is hereby granted,
   9 provided that the above copyright notice appear in all copies and that
  10 both that copyright notice and this permission notice appear in
  11 supporting documentation, and that the names of Stichting Mathematisch
  12 Centrum or CWI or Corporation for National Research Initiatives or
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  14 distribution of the software without specific, written prior
  15 permission.
  16
  17 While CWI is the initial source for this software, a modified version
  18 is made available by the Corporation for National Research Initiatives
  19 (CNRI) at the Internet address ftp://ftp.python.org.
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  21 STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
  22 REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
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  24 CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
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  29
  30 ******************************************************************/
  31
  32 /* MD5 module */
  33
  34 /* This module provides an interface to the RSA Data Security,
  35    Inc. MD5 Message-Digest Algorithm, described in RFC 1321.
  36    It requires the files md5c.c and md5.h (which are slightly changed
  37    from the versions in the RFC to avoid the "global.h" file.) */
  38
  39
  40 /* MD5 objects */
  41
  42 #include "Python.h"
  43 #include "md5.h"
  44
  45 typedef struct {
  46         PyObject_HEAD
  47         MD5_CTX md5;            /* the context holder */
  48 } md5object;
  49
  50 staticforward PyTypeObject MD5type;
  51
  52 #define is_md5object(v)         ((v)->ob_type == &MD5type)
  53
  54 static md5object *
  55 newmd5object()
  56 {
  57         md5object *md5p;
  58
  59         md5p = PyObject_NEW(md5object, &MD5type);
  60         if (md5p == NULL)
  61                 return NULL;
  62
  63         MD5Init(&md5p->md5);    /* actual initialisation */
  64         return md5p;
  65 }
  66
  67
  68 /* MD5 methods */
  69
  70 static void
  71 md5_dealloc(md5p)
  72         md5object *md5p;
  73 {
  74         PyMem_DEL(md5p);
  75 }
  76
  77
  78 /* MD5 methods-as-attributes */
  79
  80 static PyObject *
  81 md5_update(self, args)
  82         md5object *self;
  83         PyObject *args;
  84 {
  85         unsigned char *cp;
  86         int len;
  87
  88         if (!PyArg_Parse(args, "s#", &cp, &len))
  89                 return NULL;
  90
  91         MD5Update(&self->md5, cp, len);
  92
  93         Py_INCREF(Py_None);
  94         return Py_None;
  95 }
  96
  97 static char update_doc [] =
  98 "update (arg)\n\
  99 \n\
 100 Update the md5 object with the string arg. Repeated calls are\n\
 101 equivalent to a single call with the concatenation of all the\n\
 102 arguments.";
 103
 104
 105 static PyObject *
 106 md5_digest(self, args)
 107         md5object *self;
 108         PyObject *args;
 109 {
 110
 111         MD5_CTX mdContext;
 112         unsigned char aDigest[16];
 113
 114         if (!PyArg_NoArgs(args))
 115                 return NULL;
 116
 117         /* make a temporary copy, and perform the final */
 118         mdContext = self->md5;
 119         MD5Final(aDigest, &mdContext);
 120
 121         return PyString_FromStringAndSize((char *)aDigest, 16);
 122 }
 123
 124 static char digest_doc [] =
 125 "digest() -> string\n\
 126 \n\
 127 Return the digest of the strings passed to the update() method so\n\
 128 far. This is an 16-byte string which may contain non-ASCII characters,\n\
 129 including null bytes.";
 130
 131
 132 static PyObject *
 133 md5_copy(self, args)
 134         md5object *self;
 135         PyObject *args;
 136 {
 137         md5object *md5p;
 138
 139         if (!PyArg_NoArgs(args))
 140                 return NULL;
 141
 142         if ((md5p = newmd5object()) == NULL)
 143                 return NULL;
 144
 145         md5p->md5 = self->md5;
 146
 147         return (PyObject *)md5p;
 148 }
 149
 150 static char copy_doc [] =
 151 "copy() -> md5 object\n\
 152 \n\
 153 Return a copy (``clone'') of the md5 object.";
 154
 155
 156 static PyMethodDef md5_methods[] = {
 157         {"update",              (PyCFunction)md5_update, 0, update_doc},
 158         {"digest",              (PyCFunction)md5_digest, 0, digest_doc},
 159         {"copy",                (PyCFunction)md5_copy, 0, copy_doc},
 160         {NULL,                  NULL}           /* sentinel */
 161 };
 162
 163 static PyObject *
 164 md5_getattr(self, name)
 165         md5object *self;
 166         char *name;
 167 {
 168         return Py_FindMethod(md5_methods, (PyObject *)self, name);
 169 }
 170
 171 static char module_doc [] =
 172
 173 "This module implements the interface to RSA's MD5 message digest\n\
 174 algorithm (see also Internet RFC 1321). Its use is quite\n\
 175 straightforward: use the new() to create an md5 object. You can now\n\
 176 feed this object with arbitrary strings using the update() method, and\n\
 177 at any point you can ask it for the digest (a strong kind of 128-bit\n\
 178 checksum, a.k.a. ``fingerprint'') of the contatenation of the strings\n\
 179 fed to it so far using the digest() method.\n\
 180 \n\
 181 Functions:\n\
 182 \n\
 183 new([arg]) -- return a new md5 object, initialized with arg if provided\n\
 184 md5([arg]) -- DEPRECATED, same as new, but for compatibility\n\
 185 \n\
 186 Special Objects:\n\
 187 \n\
 188 MD5Type -- type object for md5 objects\n\
 189 ";
 190
 191 static char md5type_doc [] =
 192 "An md5 represents the object used to calculate the MD5 checksum of a\n\
 193 string of information.\n\
 194 \n\
 195 Methods:\n\
 196 \n\
 197 update() -- updates the current digest with an additional string\n\
 198 digest() -- return the current digest value\n\
 199 copy() -- return a copy of the current md5 object\n\
 200 ";
 201
 202 statichere PyTypeObject MD5type = {
 203         PyObject_HEAD_INIT(&PyType_Type)
 204         0,                        /*ob_size*/
 205         "md5",                    /*tp_name*/
 206         sizeof(md5object),        /*tp_size*/
 207         0,                        /*tp_itemsize*/
 208         /* methods */
 209         (destructor)md5_dealloc,  /*tp_dealloc*/
 210         0,                        /*tp_print*/
 211         (getattrfunc)md5_getattr, /*tp_getattr*/
 212         0,                        /*tp_setattr*/
 213         0,                        /*tp_compare*/
 214         0,                        /*tp_repr*/
 215         0,                        /*tp_as_number*/
 216         0,                        /*tp_as_sequence*/
 217         0,                        /*tp_as_mapping*/
 218         0,                        /*tp_hash*/
 219         0,                        /*tp_call*/
 220         0,                        /*tp_str*/
 221         0,                        /*tp_getattro*/
 222         0,                        /*tp_setattro*/
 223         0,                        /*tp_as_buffer*/
 224         0,                        /*tp_xxx4*/
 225         md5type_doc,              /*tp_doc*/
 226 };
 227
 228
 229 /* MD5 functions */
 230
 231 static PyObject *
 232 MD5_new(self, args)
 233         PyObject *self;
 234         PyObject *args;
 235 {
 236         md5object *md5p;
 237         unsigned char *cp = NULL;
 238         int len = 0;
 239
 240         if (!PyArg_ParseTuple(args, "|s#", &cp, &len))
 241                 return NULL;
 242
 243         if ((md5p = newmd5object()) == NULL)
 244                 return NULL;
 245
 246         if (cp)
 247                 MD5Update(&md5p->md5, cp, len);
 248
 249         return (PyObject *)md5p;
 250 }
 251
 252 static char new_doc [] =
 253 "new([arg]) -> md5 object\n\
 254 \n\
 255 Return a new md5 object. If arg is present, the method call update(arg)\n\
 256 is made.";
 257
 258
 259 /* List of functions exported by this module */
 260
 261 static PyMethodDef md5_functions[] = {
 262         {"new",         (PyCFunction)MD5_new, 1, new_doc},
 263         {"md5",         (PyCFunction)MD5_new, 1, new_doc}, /* Backward compatibility */
 264         {NULL,          NULL}   /* Sentinel */
 265 };
 266
 267
 268 /* Initialize this module. */
 269
 270 DL_EXPORT(void)
 271 initmd5()
 272 {
 273         PyObject *m, *d;
 274         m = Py_InitModule3("md5", md5_functions, module_doc);
 275         d = PyModule_GetDict(m);
 276         PyDict_SetItemString(d, "MD5Type", (PyObject *)&MD5type);
 277         /* No need to check the error here, the caller will do that */
 278 }