cpython/Modules/sha1module.c

538 lines
14 KiB
C

/* SHA1 module */
/* This module provides an interface to the SHA1 algorithm */
/* See below for information about the original code this module was
based upon. Additional work performed by:
Andrew Kuchling (amk@amk.ca)
Greg Stein (gstein@lyra.org)
Trevor Perrin (trevp@trevp.net)
Copyright (C) 2005-2007 Gregory P. Smith (greg@krypto.org)
Licensed to PSF under a Contributor Agreement.
*/
/* SHA1 objects */
#include "Python.h"
/* Some useful types */
#if SIZEOF_INT == 4
typedef unsigned int SHA1_INT32; /* 32-bit integer */
typedef PY_LONG_LONG SHA1_INT64; /* 64-bit integer */
#else
/* not defined. compilation will die. */
#endif
/* The SHA1 block size and message digest sizes, in bytes */
#define SHA1_BLOCKSIZE 64
#define SHA1_DIGESTSIZE 20
/* The structure for storing SHA1 info */
struct sha1_state {
SHA1_INT64 length;
SHA1_INT32 state[5], curlen;
unsigned char buf[SHA1_BLOCKSIZE];
};
typedef struct {
PyObject_HEAD
struct sha1_state hash_state;
} SHA1object;
/* ------------------------------------------------------------------------
*
* This code for the SHA1 algorithm was noted as public domain. The
* original headers are pasted below.
*
* Several changes have been made to make it more compatible with the
* Python environment and desired interface.
*
*/
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@gmail.com, http://libtom.org
*/
/* rotate the hard way (platform optimizations could be done) */
#define ROL(x, y) ( (((unsigned long)(x)<<(unsigned long)((y)&31)) | (((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL)
#define ROLc(x, y) ( (((unsigned long)(x)<<(unsigned long)((y)&31)) | (((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL)
/* Endian Neutral macros that work on all platforms */
#define STORE32H(x, y) \
{ (y)[0] = (unsigned char)(((x)>>24)&255); (y)[1] = (unsigned char)(((x)>>16)&255); \
(y)[2] = (unsigned char)(((x)>>8)&255); (y)[3] = (unsigned char)((x)&255); }
#define LOAD32H(x, y) \
{ x = ((unsigned long)((y)[0] & 255)<<24) | \
((unsigned long)((y)[1] & 255)<<16) | \
((unsigned long)((y)[2] & 255)<<8) | \
((unsigned long)((y)[3] & 255)); }
#define STORE64H(x, y) \
{ (y)[0] = (unsigned char)(((x)>>56)&255); (y)[1] = (unsigned char)(((x)>>48)&255); \
(y)[2] = (unsigned char)(((x)>>40)&255); (y)[3] = (unsigned char)(((x)>>32)&255); \
(y)[4] = (unsigned char)(((x)>>24)&255); (y)[5] = (unsigned char)(((x)>>16)&255); \
(y)[6] = (unsigned char)(((x)>>8)&255); (y)[7] = (unsigned char)((x)&255); }
#ifndef MIN
#define MIN(x, y) ( ((x)<(y))?(x):(y) )
#endif
/* SHA1 macros */
#define F0(x,y,z) (z ^ (x & (y ^ z)))
#define F1(x,y,z) (x ^ y ^ z)
#define F2(x,y,z) ((x & y) | (z & (x | y)))
#define F3(x,y,z) (x ^ y ^ z)
static void sha1_compress(struct sha1_state *sha1, unsigned char *buf)
{
SHA1_INT32 a,b,c,d,e,W[80],i;
/* copy the state into 512-bits into W[0..15] */
for (i = 0; i < 16; i++) {
LOAD32H(W[i], buf + (4*i));
}
/* copy state */
a = sha1->state[0];
b = sha1->state[1];
c = sha1->state[2];
d = sha1->state[3];
e = sha1->state[4];
/* expand it */
for (i = 16; i < 80; i++) {
W[i] = ROL(W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16], 1);
}
/* compress */
/* round one */
#define FF0(a,b,c,d,e,i) e = (ROLc(a, 5) + F0(b,c,d) + e + W[i] + 0x5a827999UL); b = ROLc(b, 30);
#define FF1(a,b,c,d,e,i) e = (ROLc(a, 5) + F1(b,c,d) + e + W[i] + 0x6ed9eba1UL); b = ROLc(b, 30);
#define FF2(a,b,c,d,e,i) e = (ROLc(a, 5) + F2(b,c,d) + e + W[i] + 0x8f1bbcdcUL); b = ROLc(b, 30);
#define FF3(a,b,c,d,e,i) e = (ROLc(a, 5) + F3(b,c,d) + e + W[i] + 0xca62c1d6UL); b = ROLc(b, 30);
for (i = 0; i < 20; ) {
FF0(a,b,c,d,e,i++);
FF0(e,a,b,c,d,i++);
FF0(d,e,a,b,c,i++);
FF0(c,d,e,a,b,i++);
FF0(b,c,d,e,a,i++);
}
/* round two */
for (; i < 40; ) {
FF1(a,b,c,d,e,i++);
FF1(e,a,b,c,d,i++);
FF1(d,e,a,b,c,i++);
FF1(c,d,e,a,b,i++);
FF1(b,c,d,e,a,i++);
}
/* round three */
for (; i < 60; ) {
FF2(a,b,c,d,e,i++);
FF2(e,a,b,c,d,i++);
FF2(d,e,a,b,c,i++);
FF2(c,d,e,a,b,i++);
FF2(b,c,d,e,a,i++);
}
/* round four */
for (; i < 80; ) {
FF3(a,b,c,d,e,i++);
FF3(e,a,b,c,d,i++);
FF3(d,e,a,b,c,i++);
FF3(c,d,e,a,b,i++);
FF3(b,c,d,e,a,i++);
}
#undef FF0
#undef FF1
#undef FF2
#undef FF3
/* store */
sha1->state[0] = sha1->state[0] + a;
sha1->state[1] = sha1->state[1] + b;
sha1->state[2] = sha1->state[2] + c;
sha1->state[3] = sha1->state[3] + d;
sha1->state[4] = sha1->state[4] + e;
}
/**
Initialize the hash state
@param sha1 The hash state you wish to initialize
*/
void sha1_init(struct sha1_state *sha1)
{
assert(sha1 != NULL);
sha1->state[0] = 0x67452301UL;
sha1->state[1] = 0xefcdab89UL;
sha1->state[2] = 0x98badcfeUL;
sha1->state[3] = 0x10325476UL;
sha1->state[4] = 0xc3d2e1f0UL;
sha1->curlen = 0;
sha1->length = 0;
}
/**
Process a block of memory though the hash
@param sha1 The hash state
@param in The data to hash
@param inlen The length of the data (octets)
*/
void sha1_process(struct sha1_state *sha1,
const unsigned char *in, unsigned long inlen)
{
unsigned long n;
assert(sha1 != NULL);
assert(in != NULL);
assert(sha1->curlen <= sizeof(sha1->buf));
while (inlen > 0) {
if (sha1->curlen == 0 && inlen >= SHA1_BLOCKSIZE) {
sha1_compress(sha1, (unsigned char *)in);
sha1->length += SHA1_BLOCKSIZE * 8;
in += SHA1_BLOCKSIZE;
inlen -= SHA1_BLOCKSIZE;
} else {
n = MIN(inlen, (SHA1_BLOCKSIZE - sha1->curlen));
memcpy(sha1->buf + sha1->curlen, in, (size_t)n);
sha1->curlen += n;
in += n;
inlen -= n;
if (sha1->curlen == SHA1_BLOCKSIZE) {
sha1_compress(sha1, sha1->buf);
sha1->length += 8*SHA1_BLOCKSIZE;
sha1->curlen = 0;
}
}
}
}
/**
Terminate the hash to get the digest
@param sha1 The hash state
@param out [out] The destination of the hash (20 bytes)
*/
void sha1_done(struct sha1_state *sha1, unsigned char *out)
{
int i;
assert(sha1 != NULL);
assert(out != NULL);
assert(sha1->curlen < sizeof(sha1->buf));
/* increase the length of the message */
sha1->length += sha1->curlen * 8;
/* append the '1' bit */
sha1->buf[sha1->curlen++] = (unsigned char)0x80;
/* if the length is currently above 56 bytes we append zeros
* then compress. Then we can fall back to padding zeros and length
* encoding like normal.
*/
if (sha1->curlen > 56) {
while (sha1->curlen < 64) {
sha1->buf[sha1->curlen++] = (unsigned char)0;
}
sha1_compress(sha1, sha1->buf);
sha1->curlen = 0;
}
/* pad upto 56 bytes of zeroes */
while (sha1->curlen < 56) {
sha1->buf[sha1->curlen++] = (unsigned char)0;
}
/* store length */
STORE64H(sha1->length, sha1->buf+56);
sha1_compress(sha1, sha1->buf);
/* copy output */
for (i = 0; i < 5; i++) {
STORE32H(sha1->state[i], out+(4*i));
}
}
/* .Source: /cvs/libtom/libtomcrypt/src/hashes/sha1.c,v $ */
/* .Revision: 1.10 $ */
/* .Date: 2007/05/12 14:25:28 $ */
/*
* End of copied SHA1 code.
*
* ------------------------------------------------------------------------
*/
static PyTypeObject SHA1type;
static SHA1object *
newSHA1object(void)
{
return (SHA1object *)PyObject_New(SHA1object, &SHA1type);
}
/* Internal methods for a hash object */
static void
SHA1_dealloc(PyObject *ptr)
{
PyObject_Del(ptr);
}
/* External methods for a hash object */
PyDoc_STRVAR(SHA1_copy__doc__, "Return a copy of the hash object.");
static PyObject *
SHA1_copy(SHA1object *self, PyObject *unused)
{
SHA1object *newobj;
if (Py_Type(self) == &SHA1type) {
if ( (newobj = newSHA1object())==NULL)
return NULL;
} else {
if ( (newobj = newSHA1object())==NULL)
return NULL;
}
newobj->hash_state = self->hash_state;
return (PyObject *)newobj;
}
PyDoc_STRVAR(SHA1_digest__doc__,
"Return the digest value as a string of binary data.");
static PyObject *
SHA1_digest(SHA1object *self, PyObject *unused)
{
unsigned char digest[SHA1_DIGESTSIZE];
struct sha1_state temp;
temp = self->hash_state;
sha1_done(&temp, digest);
return PyString_FromStringAndSize((const char *)digest, SHA1_DIGESTSIZE);
}
PyDoc_STRVAR(SHA1_hexdigest__doc__,
"Return the digest value as a string of hexadecimal digits.");
static PyObject *
SHA1_hexdigest(SHA1object *self, PyObject *unused)
{
unsigned char digest[SHA1_DIGESTSIZE];
struct sha1_state temp;
PyObject *retval;
Py_UNICODE *hex_digest;
int i, j;
/* Get the raw (binary) digest value */
temp = self->hash_state;
sha1_done(&temp, digest);
/* Create a new string */
retval = PyUnicode_FromStringAndSize(NULL, SHA1_DIGESTSIZE * 2);
if (!retval)
return NULL;
hex_digest = PyUnicode_AS_UNICODE(retval);
if (!hex_digest) {
Py_DECREF(retval);
return NULL;
}
/* Make hex version of the digest */
for(i=j=0; i<SHA1_DIGESTSIZE; i++) {
char c;
c = (digest[i] >> 4) & 0xf;
c = (c>9) ? c+'a'-10 : c + '0';
hex_digest[j++] = c;
c = (digest[i] & 0xf);
c = (c>9) ? c+'a'-10 : c + '0';
hex_digest[j++] = c;
}
return retval;
}
PyDoc_STRVAR(SHA1_update__doc__,
"Update this hash object's state with the provided string.");
static PyObject *
SHA1_update(SHA1object *self, PyObject *args)
{
unsigned char *cp;
int len;
if (!PyArg_ParseTuple(args, "s#:update", &cp, &len))
return NULL;
sha1_process(&self->hash_state, cp, len);
Py_INCREF(Py_None);
return Py_None;
}
static PyMethodDef SHA1_methods[] = {
{"copy", (PyCFunction)SHA1_copy, METH_NOARGS, SHA1_copy__doc__},
{"digest", (PyCFunction)SHA1_digest, METH_NOARGS, SHA1_digest__doc__},
{"hexdigest", (PyCFunction)SHA1_hexdigest, METH_NOARGS, SHA1_hexdigest__doc__},
{"update", (PyCFunction)SHA1_update, METH_VARARGS, SHA1_update__doc__},
{NULL, NULL} /* sentinel */
};
static PyObject *
SHA1_get_block_size(PyObject *self, void *closure)
{
return PyLong_FromLong(SHA1_BLOCKSIZE);
}
static PyObject *
SHA1_get_name(PyObject *self, void *closure)
{
return PyUnicode_FromStringAndSize("SHA1", 3);
}
static PyObject *
sha1_get_digest_size(PyObject *self, void *closure)
{
return PyLong_FromLong(SHA1_DIGESTSIZE);
}
static PyGetSetDef SHA1_getseters[] = {
{"block_size",
(getter)SHA1_get_block_size, NULL,
NULL,
NULL},
{"name",
(getter)SHA1_get_name, NULL,
NULL,
NULL},
{"digest_size",
(getter)sha1_get_digest_size, NULL,
NULL,
NULL},
{NULL} /* Sentinel */
};
static PyTypeObject SHA1type = {
PyVarObject_HEAD_INIT(NULL, 0)
"_sha1.sha1", /*tp_name*/
sizeof(SHA1object), /*tp_size*/
0, /*tp_itemsize*/
/* methods */
SHA1_dealloc, /*tp_dealloc*/
0, /*tp_print*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_compare*/
0, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /*tp_hash*/
0, /*tp_call*/
0, /*tp_str*/
0, /*tp_getattro*/
0, /*tp_setattro*/
0, /*tp_as_buffer*/
Py_TPFLAGS_DEFAULT, /*tp_flags*/
0, /*tp_doc*/
0, /*tp_traverse*/
0, /*tp_clear*/
0, /*tp_richcompare*/
0, /*tp_weaklistoffset*/
0, /*tp_iter*/
0, /*tp_iternext*/
SHA1_methods, /* tp_methods */
NULL, /* tp_members */
SHA1_getseters, /* tp_getset */
};
/* The single module-level function: new() */
PyDoc_STRVAR(SHA1_new__doc__,
"Return a new SHA1 hash object; optionally initialized with a string.");
static PyObject *
SHA1_new(PyObject *self, PyObject *args, PyObject *kwdict)
{
static char *kwlist[] = {"string", NULL};
SHA1object *new;
unsigned char *cp = NULL;
int len;
if (!PyArg_ParseTupleAndKeywords(args, kwdict, "|s#:new", kwlist,
&cp, &len)) {
return NULL;
}
if ((new = newSHA1object()) == NULL)
return NULL;
sha1_init(&new->hash_state);
if (PyErr_Occurred()) {
Py_DECREF(new);
return NULL;
}
if (cp)
sha1_process(&new->hash_state, cp, len);
return (PyObject *)new;
}
/* List of functions exported by this module */
static struct PyMethodDef SHA1_functions[] = {
{"sha1",(PyCFunction)SHA1_new, METH_VARARGS|METH_KEYWORDS,SHA1_new__doc__},
{NULL, NULL} /* Sentinel */
};
/* Initialize this module. */
#define insint(n,v) { PyModule_AddIntConstant(m,n,v); }
PyMODINIT_FUNC
init_sha1(void)
{
PyObject *m;
Py_Type(&SHA1type) = &PyType_Type;
if (PyType_Ready(&SHA1type) < 0)
return;
m = Py_InitModule("_sha1", SHA1_functions);
if (m == NULL)
return;
}