3 /* This module provides an interface to NIST's Secure Hash Algorithm */
5 /* See below for information about the original code this module was
6 based upon. Additional work performed by:
8 Andrew Kuchling (amk@amk.ca)
9 Greg Stein (gstein@lyra.org)
11 Copyright (C) 2005 Gregory P. Smith (greg@krypto.org)
12 Licensed to PSF under a Contributor Agreement.
19 #include "structmember.h"
22 /* Endianness testing and definitions */
23 #define TestEndianness(variable) {int i=1; variable=PCT_BIG_ENDIAN;\
24 if (*((char*)&i)==1) variable=PCT_LITTLE_ENDIAN;}
26 #define PCT_LITTLE_ENDIAN 1
27 #define PCT_BIG_ENDIAN 0
29 /* Some useful types */
31 typedef unsigned char SHA_BYTE
;
34 typedef unsigned int SHA_INT32
; /* 32-bit integer */
36 /* not defined. compilation will die. */
39 /* The SHA block size and message digest sizes, in bytes */
41 #define SHA_BLOCKSIZE 64
42 #define SHA_DIGESTSIZE 20
44 /* The structure for storing SHS info */
48 SHA_INT32 digest
[5]; /* Message digest */
49 SHA_INT32 count_lo
, count_hi
; /* 64-bit bit count */
50 SHA_BYTE data
[SHA_BLOCKSIZE
]; /* SHA data buffer */
52 int local
; /* unprocessed amount in data */
55 /* When run on a little-endian CPU we need to perform byte reversal on an
56 array of longwords. */
58 static void longReverse(SHA_INT32
*buffer
, int byteCount
, int Endianness
)
62 if ( Endianness
== PCT_BIG_ENDIAN
)
65 byteCount
/= sizeof(*buffer
);
68 value
= ( ( value
& 0xFF00FF00L
) >> 8 ) | \
69 ( ( value
& 0x00FF00FFL
) << 8 );
70 *buffer
++ = ( value
<< 16 ) | ( value
>> 16 );
74 static void SHAcopy(SHAobject
*src
, SHAobject
*dest
)
76 dest
->Endianness
= src
->Endianness
;
77 dest
->local
= src
->local
;
78 dest
->count_lo
= src
->count_lo
;
79 dest
->count_hi
= src
->count_hi
;
80 memcpy(dest
->digest
, src
->digest
, sizeof(src
->digest
));
81 memcpy(dest
->data
, src
->data
, sizeof(src
->data
));
85 /* ------------------------------------------------------------------------
87 * This code for the SHA algorithm was noted as public domain. The original
88 * headers are pasted below.
90 * Several changes have been made to make it more compatible with the
91 * Python environment and desired interface.
95 /* NIST Secure Hash Algorithm */
96 /* heavily modified by Uwe Hollerbach <uh@alumni.caltech edu> */
97 /* from Peter C. Gutmann's implementation as found in */
98 /* Applied Cryptography by Bruce Schneier */
99 /* Further modifications to include the "UNRAVEL" stuff, below */
101 /* This code is in the public domain */
103 /* UNRAVEL should be fastest & biggest */
104 /* UNROLL_LOOPS should be just as big, but slightly slower */
105 /* both undefined should be smallest and slowest */
108 /* #define UNROLL_LOOPS */
110 /* The SHA f()-functions. The f1 and f3 functions can be optimized to
111 save one boolean operation each - thanks to Rich Schroeppel,
112 rcs@cs.arizona.edu for discovering this */
114 /*#define f1(x,y,z) ((x & y) | (~x & z)) // Rounds 0-19 */
115 #define f1(x,y,z) (z ^ (x & (y ^ z))) /* Rounds 0-19 */
116 #define f2(x,y,z) (x ^ y ^ z) /* Rounds 20-39 */
117 /*#define f3(x,y,z) ((x & y) | (x & z) | (y & z)) // Rounds 40-59 */
118 #define f3(x,y,z) ((x & y) | (z & (x | y))) /* Rounds 40-59 */
119 #define f4(x,y,z) (x ^ y ^ z) /* Rounds 60-79 */
123 #define CONST1 0x5a827999L /* Rounds 0-19 */
124 #define CONST2 0x6ed9eba1L /* Rounds 20-39 */
125 #define CONST3 0x8f1bbcdcL /* Rounds 40-59 */
126 #define CONST4 0xca62c1d6L /* Rounds 60-79 */
130 #define R32(x,n) ((x << n) | (x >> (32 - n)))
132 /* the generic case, for when the overall rotation is not unraveled */
135 T = R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; \
136 E = D; D = C; C = R32(B,30); B = A; A = T
138 /* specific cases, for when the overall rotation is unraveled */
141 T = R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; B = R32(B,30)
144 E = R32(T,5) + f##n(A,B,C) + D + *WP++ + CONST##n; A = R32(A,30)
147 D = R32(E,5) + f##n(T,A,B) + C + *WP++ + CONST##n; T = R32(T,30)
150 C = R32(D,5) + f##n(E,T,A) + B + *WP++ + CONST##n; E = R32(E,30)
153 B = R32(C,5) + f##n(D,E,T) + A + *WP++ + CONST##n; D = R32(D,30)
156 A = R32(B,5) + f##n(C,D,E) + T + *WP++ + CONST##n; C = R32(C,30)
158 /* do SHA transformation */
161 sha_transform(SHAobject
*sha_info
)
164 SHA_INT32 T
, A
, B
, C
, D
, E
, W
[80], *WP
;
166 memcpy(W
, sha_info
->data
, sizeof(sha_info
->data
));
167 longReverse(W
, (int)sizeof(sha_info
->data
), sha_info
->Endianness
);
169 for (i
= 16; i
< 80; ++i
) {
170 W
[i
] = W
[i
-3] ^ W
[i
-8] ^ W
[i
-14] ^ W
[i
-16];
172 /* extra rotation fix */
175 A
= sha_info
->digest
[0];
176 B
= sha_info
->digest
[1];
177 C
= sha_info
->digest
[2];
178 D
= sha_info
->digest
[3];
179 E
= sha_info
->digest
[4];
182 FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1);
183 FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1);
184 FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2);
185 FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2);
186 FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3);
187 FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3);
188 FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4);
189 FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4);
190 sha_info
->digest
[0] += E
;
191 sha_info
->digest
[1] += T
;
192 sha_info
->digest
[2] += A
;
193 sha_info
->digest
[3] += B
;
194 sha_info
->digest
[4] += C
;
197 FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1);
198 FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1);
199 FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2);
200 FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2);
201 FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3);
202 FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3);
203 FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4);
204 FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4);
205 #else /* !UNROLL_LOOPS */
206 for (i
= 0; i
< 20; ++i
) { FG(1); }
207 for (i
= 20; i
< 40; ++i
) { FG(2); }
208 for (i
= 40; i
< 60; ++i
) { FG(3); }
209 for (i
= 60; i
< 80; ++i
) { FG(4); }
210 #endif /* !UNROLL_LOOPS */
211 sha_info
->digest
[0] += A
;
212 sha_info
->digest
[1] += B
;
213 sha_info
->digest
[2] += C
;
214 sha_info
->digest
[3] += D
;
215 sha_info
->digest
[4] += E
;
216 #endif /* !UNRAVEL */
219 /* initialize the SHA digest */
222 sha_init(SHAobject
*sha_info
)
224 TestEndianness(sha_info
->Endianness
)
226 sha_info
->digest
[0] = 0x67452301L
;
227 sha_info
->digest
[1] = 0xefcdab89L
;
228 sha_info
->digest
[2] = 0x98badcfeL
;
229 sha_info
->digest
[3] = 0x10325476L
;
230 sha_info
->digest
[4] = 0xc3d2e1f0L
;
231 sha_info
->count_lo
= 0L;
232 sha_info
->count_hi
= 0L;
236 /* update the SHA digest */
239 sha_update(SHAobject
*sha_info
, SHA_BYTE
*buffer
, int count
)
244 clo
= sha_info
->count_lo
+ ((SHA_INT32
) count
<< 3);
245 if (clo
< sha_info
->count_lo
) {
246 ++sha_info
->count_hi
;
248 sha_info
->count_lo
= clo
;
249 sha_info
->count_hi
+= (SHA_INT32
) count
>> 29;
250 if (sha_info
->local
) {
251 i
= SHA_BLOCKSIZE
- sha_info
->local
;
255 memcpy(((SHA_BYTE
*) sha_info
->data
) + sha_info
->local
, buffer
, i
);
258 sha_info
->local
+= i
;
259 if (sha_info
->local
== SHA_BLOCKSIZE
) {
260 sha_transform(sha_info
);
266 while (count
>= SHA_BLOCKSIZE
) {
267 memcpy(sha_info
->data
, buffer
, SHA_BLOCKSIZE
);
268 buffer
+= SHA_BLOCKSIZE
;
269 count
-= SHA_BLOCKSIZE
;
270 sha_transform(sha_info
);
272 memcpy(sha_info
->data
, buffer
, count
);
273 sha_info
->local
= count
;
276 /* finish computing the SHA digest */
279 sha_final(unsigned char digest
[20], SHAobject
*sha_info
)
282 SHA_INT32 lo_bit_count
, hi_bit_count
;
284 lo_bit_count
= sha_info
->count_lo
;
285 hi_bit_count
= sha_info
->count_hi
;
286 count
= (int) ((lo_bit_count
>> 3) & 0x3f);
287 ((SHA_BYTE
*) sha_info
->data
)[count
++] = 0x80;
288 if (count
> SHA_BLOCKSIZE
- 8) {
289 memset(((SHA_BYTE
*) sha_info
->data
) + count
, 0,
290 SHA_BLOCKSIZE
- count
);
291 sha_transform(sha_info
);
292 memset((SHA_BYTE
*) sha_info
->data
, 0, SHA_BLOCKSIZE
- 8);
295 memset(((SHA_BYTE
*) sha_info
->data
) + count
, 0,
296 SHA_BLOCKSIZE
- 8 - count
);
299 /* GJS: note that we add the hi/lo in big-endian. sha_transform will
300 swap these values into host-order. */
301 sha_info
->data
[56] = (hi_bit_count
>> 24) & 0xff;
302 sha_info
->data
[57] = (hi_bit_count
>> 16) & 0xff;
303 sha_info
->data
[58] = (hi_bit_count
>> 8) & 0xff;
304 sha_info
->data
[59] = (hi_bit_count
>> 0) & 0xff;
305 sha_info
->data
[60] = (lo_bit_count
>> 24) & 0xff;
306 sha_info
->data
[61] = (lo_bit_count
>> 16) & 0xff;
307 sha_info
->data
[62] = (lo_bit_count
>> 8) & 0xff;
308 sha_info
->data
[63] = (lo_bit_count
>> 0) & 0xff;
309 sha_transform(sha_info
);
310 digest
[ 0] = (unsigned char) ((sha_info
->digest
[0] >> 24) & 0xff);
311 digest
[ 1] = (unsigned char) ((sha_info
->digest
[0] >> 16) & 0xff);
312 digest
[ 2] = (unsigned char) ((sha_info
->digest
[0] >> 8) & 0xff);
313 digest
[ 3] = (unsigned char) ((sha_info
->digest
[0] ) & 0xff);
314 digest
[ 4] = (unsigned char) ((sha_info
->digest
[1] >> 24) & 0xff);
315 digest
[ 5] = (unsigned char) ((sha_info
->digest
[1] >> 16) & 0xff);
316 digest
[ 6] = (unsigned char) ((sha_info
->digest
[1] >> 8) & 0xff);
317 digest
[ 7] = (unsigned char) ((sha_info
->digest
[1] ) & 0xff);
318 digest
[ 8] = (unsigned char) ((sha_info
->digest
[2] >> 24) & 0xff);
319 digest
[ 9] = (unsigned char) ((sha_info
->digest
[2] >> 16) & 0xff);
320 digest
[10] = (unsigned char) ((sha_info
->digest
[2] >> 8) & 0xff);
321 digest
[11] = (unsigned char) ((sha_info
->digest
[2] ) & 0xff);
322 digest
[12] = (unsigned char) ((sha_info
->digest
[3] >> 24) & 0xff);
323 digest
[13] = (unsigned char) ((sha_info
->digest
[3] >> 16) & 0xff);
324 digest
[14] = (unsigned char) ((sha_info
->digest
[3] >> 8) & 0xff);
325 digest
[15] = (unsigned char) ((sha_info
->digest
[3] ) & 0xff);
326 digest
[16] = (unsigned char) ((sha_info
->digest
[4] >> 24) & 0xff);
327 digest
[17] = (unsigned char) ((sha_info
->digest
[4] >> 16) & 0xff);
328 digest
[18] = (unsigned char) ((sha_info
->digest
[4] >> 8) & 0xff);
329 digest
[19] = (unsigned char) ((sha_info
->digest
[4] ) & 0xff);
333 * End of copied SHA code.
335 * ------------------------------------------------------------------------
338 static PyTypeObject SHAtype
;
344 return (SHAobject
*)PyObject_New(SHAobject
, &SHAtype
);
347 /* Internal methods for a hashing object */
350 SHA_dealloc(PyObject
*ptr
)
356 /* External methods for a hashing object */
358 PyDoc_STRVAR(SHA_copy__doc__
, "Return a copy of the hashing object.");
361 SHA_copy(SHAobject
*self
, PyObject
*unused
)
365 if ( (newobj
= newSHAobject())==NULL
)
368 SHAcopy(self
, newobj
);
369 return (PyObject
*)newobj
;
372 PyDoc_STRVAR(SHA_digest__doc__
,
373 "Return the digest value as a string of binary data.");
376 SHA_digest(SHAobject
*self
, PyObject
*unused
)
378 unsigned char digest
[SHA_DIGESTSIZE
];
381 SHAcopy(self
, &temp
);
382 sha_final(digest
, &temp
);
383 return PyString_FromStringAndSize((const char *)digest
, sizeof(digest
));
386 PyDoc_STRVAR(SHA_hexdigest__doc__
,
387 "Return the digest value as a string of hexadecimal digits.");
390 SHA_hexdigest(SHAobject
*self
, PyObject
*unused
)
392 unsigned char digest
[SHA_DIGESTSIZE
];
398 /* Get the raw (binary) digest value */
399 SHAcopy(self
, &temp
);
400 sha_final(digest
, &temp
);
402 /* Create a new string */
403 retval
= PyString_FromStringAndSize(NULL
, sizeof(digest
) * 2);
406 hex_digest
= PyString_AsString(retval
);
412 /* Make hex version of the digest */
413 for(i
=j
=0; i
<sizeof(digest
); i
++) {
415 c
= (digest
[i
] >> 4) & 0xf;
416 c
= (c
>9) ? c
+'a'-10 : c
+ '0';
418 c
= (digest
[i
] & 0xf);
419 c
= (c
>9) ? c
+'a'-10 : c
+ '0';
425 PyDoc_STRVAR(SHA_update__doc__
,
426 "Update this hashing object's state with the provided string.");
429 SHA_update(SHAobject
*self
, PyObject
*args
)
434 if (!PyArg_ParseTuple(args
, "s#:update", &cp
, &len
))
437 sha_update(self
, cp
, len
);
443 static PyMethodDef SHA_methods
[] = {
444 {"copy", (PyCFunction
)SHA_copy
, METH_NOARGS
, SHA_copy__doc__
},
445 {"digest", (PyCFunction
)SHA_digest
, METH_NOARGS
, SHA_digest__doc__
},
446 {"hexdigest", (PyCFunction
)SHA_hexdigest
, METH_NOARGS
, SHA_hexdigest__doc__
},
447 {"update", (PyCFunction
)SHA_update
, METH_VARARGS
, SHA_update__doc__
},
448 {NULL
, NULL
} /* sentinel */
452 SHA_get_block_size(PyObject
*self
, void *closure
)
454 return PyInt_FromLong(SHA_BLOCKSIZE
);
458 SHA_get_digest_size(PyObject
*self
, void *closure
)
460 return PyInt_FromLong(SHA_DIGESTSIZE
);
464 SHA_get_name(PyObject
*self
, void *closure
)
466 return PyString_FromStringAndSize("SHA1", 4);
469 static PyGetSetDef SHA_getseters
[] = {
471 (getter
)SHA_get_digest_size
, NULL
,
475 (getter
)SHA_get_block_size
, NULL
,
479 (getter
)SHA_get_name
, NULL
,
482 /* the old md5 and sha modules support 'digest_size' as in PEP 247.
483 * the old sha module also supported 'digestsize'. ugh. */
485 (getter
)SHA_get_digest_size
, NULL
,
488 {NULL
} /* Sentinel */
491 static PyTypeObject SHAtype
= {
492 PyVarObject_HEAD_INIT(NULL
, 0)
493 "_sha.sha", /*tp_name*/
494 sizeof(SHAobject
), /*tp_size*/
497 SHA_dealloc
, /*tp_dealloc*/
504 0, /*tp_as_sequence*/
512 Py_TPFLAGS_DEFAULT
, /*tp_flags*/
516 0, /*tp_richcompare*/
517 0, /*tp_weaklistoffset*/
520 SHA_methods
, /* tp_methods */
522 SHA_getseters
, /* tp_getset */
526 /* The single module-level function: new() */
528 PyDoc_STRVAR(SHA_new__doc__
,
529 "Return a new SHA hashing object. An optional string argument\n\
530 may be provided; if present, this string will be automatically\n\
534 SHA_new(PyObject
*self
, PyObject
*args
, PyObject
*kwdict
)
536 static char *kwlist
[] = {"string", NULL
};
538 unsigned char *cp
= NULL
;
541 if (!PyArg_ParseTupleAndKeywords(args
, kwdict
, "|s#:new", kwlist
,
546 if ((new = newSHAobject()) == NULL
)
551 if (PyErr_Occurred()) {
556 sha_update(new, cp
, len
);
558 return (PyObject
*)new;
562 /* List of functions exported by this module */
564 static struct PyMethodDef SHA_functions
[] = {
565 {"new", (PyCFunction
)SHA_new
, METH_VARARGS
|METH_KEYWORDS
, SHA_new__doc__
},
566 {NULL
, NULL
} /* Sentinel */
570 /* Initialize this module. */
572 #define insint(n,v) { PyModule_AddIntConstant(m,n,v); }
579 Py_Type(&SHAtype
) = &PyType_Type
;
580 if (PyType_Ready(&SHAtype
) < 0)
582 m
= Py_InitModule("_sha", SHA_functions
);
586 /* Add some symbolic constants to the module */
587 insint("blocksize", 1); /* For future use, in case some hash
588 functions require an integral number of
590 insint("digestsize", 20);
591 insint("digest_size", 20);