cpython/Modules/sha1module.c
2021-02-12 02:34:11 -08:00

591 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"
#include "hashlib.h"
#include "pystrhex.h"
/*[clinic input]
module _sha1
class SHA1Type "SHA1object *" "&PyType_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=3dc9a20d1becb759]*/
/* Some useful types */
#if SIZEOF_INT == 4
typedef unsigned int SHA1_INT32; /* 32-bit integer */
typedef 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;
#include "clinic/sha1module.c.h"
/* ------------------------------------------------------------------------
*
* 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, https://www.libtom.net
*/
/* 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); }
/* 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 FF_0(a,b,c,d,e,i) e = (ROLc(a, 5) + F0(b,c,d) + e + W[i] + 0x5a827999UL); b = ROLc(b, 30);
#define FF_1(a,b,c,d,e,i) e = (ROLc(a, 5) + F1(b,c,d) + e + W[i] + 0x6ed9eba1UL); b = ROLc(b, 30);
#define FF_2(a,b,c,d,e,i) e = (ROLc(a, 5) + F2(b,c,d) + e + W[i] + 0x8f1bbcdcUL); b = ROLc(b, 30);
#define FF_3(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; ) {
FF_0(a,b,c,d,e,i++);
FF_0(e,a,b,c,d,i++);
FF_0(d,e,a,b,c,i++);
FF_0(c,d,e,a,b,i++);
FF_0(b,c,d,e,a,i++);
}
/* round two */
for (; i < 40; ) {
FF_1(a,b,c,d,e,i++);
FF_1(e,a,b,c,d,i++);
FF_1(d,e,a,b,c,i++);
FF_1(c,d,e,a,b,i++);
FF_1(b,c,d,e,a,i++);
}
/* round three */
for (; i < 60; ) {
FF_2(a,b,c,d,e,i++);
FF_2(e,a,b,c,d,i++);
FF_2(d,e,a,b,c,i++);
FF_2(c,d,e,a,b,i++);
FF_2(b,c,d,e,a,i++);
}
/* round four */
for (; i < 80; ) {
FF_3(a,b,c,d,e,i++);
FF_3(e,a,b,c,d,i++);
FF_3(d,e,a,b,c,i++);
FF_3(c,d,e,a,b,i++);
FF_3(b,c,d,e,a,i++);
}
#undef FF_0
#undef FF_1
#undef FF_2
#undef FF_3
/* 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
*/
static 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)
*/
static void
sha1_process(struct sha1_state *sha1,
const unsigned char *in, Py_ssize_t inlen)
{
Py_ssize_t 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 = Py_MIN(inlen, (Py_ssize_t)(SHA1_BLOCKSIZE - sha1->curlen));
memcpy(sha1->buf + sha1->curlen, in, (size_t)n);
sha1->curlen += (SHA1_INT32)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)
*/
static 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.
*
* ------------------------------------------------------------------------
*/
typedef struct {
PyTypeObject* sha1_type;
} SHA1State;
static inline SHA1State*
sha1_get_state(PyObject *module)
{
void *state = PyModule_GetState(module);
assert(state != NULL);
return (SHA1State *)state;
}
static SHA1object *
newSHA1object(SHA1State *st)
{
return (SHA1object *)PyObject_New(SHA1object, st->sha1_type);
}
/* Internal methods for a hash object */
static void
SHA1_dealloc(PyObject *ptr)
{
PyTypeObject *tp = Py_TYPE(ptr);
PyObject_Free(ptr);
Py_DECREF(tp);
}
/* External methods for a hash object */
/*[clinic input]
SHA1Type.copy
cls: defining_class
Return a copy of the hash object.
[clinic start generated code]*/
static PyObject *
SHA1Type_copy_impl(SHA1object *self, PyTypeObject *cls)
/*[clinic end generated code: output=b32d4461ce8bc7a7 input=6c22e66fcc34c58e]*/
{
SHA1State *st = PyType_GetModuleState(cls);
SHA1object *newobj;
if ((newobj = newSHA1object(st)) == NULL)
return NULL;
newobj->hash_state = self->hash_state;
return (PyObject *)newobj;
}
/*[clinic input]
SHA1Type.digest
Return the digest value as a bytes object.
[clinic start generated code]*/
static PyObject *
SHA1Type_digest_impl(SHA1object *self)
/*[clinic end generated code: output=2f05302a7aa2b5cb input=13824b35407444bd]*/
{
unsigned char digest[SHA1_DIGESTSIZE];
struct sha1_state temp;
temp = self->hash_state;
sha1_done(&temp, digest);
return PyBytes_FromStringAndSize((const char *)digest, SHA1_DIGESTSIZE);
}
/*[clinic input]
SHA1Type.hexdigest
Return the digest value as a string of hexadecimal digits.
[clinic start generated code]*/
static PyObject *
SHA1Type_hexdigest_impl(SHA1object *self)
/*[clinic end generated code: output=4161fd71e68c6659 input=97691055c0c74ab0]*/
{
unsigned char digest[SHA1_DIGESTSIZE];
struct sha1_state temp;
/* Get the raw (binary) digest value */
temp = self->hash_state;
sha1_done(&temp, digest);
return _Py_strhex((const char *)digest, SHA1_DIGESTSIZE);
}
/*[clinic input]
SHA1Type.update
obj: object
/
Update this hash object's state with the provided string.
[clinic start generated code]*/
static PyObject *
SHA1Type_update(SHA1object *self, PyObject *obj)
/*[clinic end generated code: output=d9902f0e5015e9ae input=aad8e07812edbba3]*/
{
Py_buffer buf;
GET_BUFFER_VIEW_OR_ERROUT(obj, &buf);
sha1_process(&self->hash_state, buf.buf, buf.len);
PyBuffer_Release(&buf);
Py_RETURN_NONE;
}
static PyMethodDef SHA1_methods[] = {
SHA1TYPE_COPY_METHODDEF
SHA1TYPE_DIGEST_METHODDEF
SHA1TYPE_HEXDIGEST_METHODDEF
SHA1TYPE_UPDATE_METHODDEF
{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", 4);
}
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 PyType_Slot sha1_type_slots[] = {
{Py_tp_dealloc, SHA1_dealloc},
{Py_tp_methods, SHA1_methods},
{Py_tp_getset, SHA1_getseters},
{0,0}
};
static PyType_Spec sha1_type_spec = {
.name = "_sha1.sha1",
.basicsize = sizeof(SHA1object),
.flags = Py_TPFLAGS_DEFAULT,
.slots = sha1_type_slots
};
/* The single module-level function: new() */
/*[clinic input]
_sha1.sha1
string: object(c_default="NULL") = b''
*
usedforsecurity: bool = True
Return a new SHA1 hash object; optionally initialized with a string.
[clinic start generated code]*/
static PyObject *
_sha1_sha1_impl(PyObject *module, PyObject *string, int usedforsecurity)
/*[clinic end generated code: output=6f8b3af05126e18e input=bd54b68e2bf36a8a]*/
{
SHA1object *new;
Py_buffer buf;
if (string)
GET_BUFFER_VIEW_OR_ERROUT(string, &buf);
SHA1State *st = sha1_get_state(module);
if ((new = newSHA1object(st)) == NULL) {
if (string)
PyBuffer_Release(&buf);
return NULL;
}
sha1_init(&new->hash_state);
if (PyErr_Occurred()) {
Py_DECREF(new);
if (string)
PyBuffer_Release(&buf);
return NULL;
}
if (string) {
sha1_process(&new->hash_state, buf.buf, buf.len);
PyBuffer_Release(&buf);
}
return (PyObject *)new;
}
/* List of functions exported by this module */
static struct PyMethodDef SHA1_functions[] = {
_SHA1_SHA1_METHODDEF
{NULL, NULL} /* Sentinel */
};
static int
_sha1_traverse(PyObject *module, visitproc visit, void *arg)
{
SHA1State *state = sha1_get_state(module);
Py_VISIT(state->sha1_type);
return 0;
}
static int
_sha1_clear(PyObject *module)
{
SHA1State *state = sha1_get_state(module);
Py_CLEAR(state->sha1_type);
return 0;
}
static void
_sha1_free(void *module)
{
_sha1_clear((PyObject *)module);
}
static int
_sha1_exec(PyObject *module)
{
SHA1State* st = sha1_get_state(module);
st->sha1_type = (PyTypeObject *)PyType_FromModuleAndSpec(
module, &sha1_type_spec, NULL);
if (st->sha1_type == NULL) {
return -1;
}
Py_INCREF(st->sha1_type);
if (PyModule_AddObject(module,
"SHA1Type",
(PyObject *)st->sha1_type) < 0) {
Py_DECREF(st->sha1_type);
return -1;
}
return 0;
}
/* Initialize this module. */
static PyModuleDef_Slot _sha1_slots[] = {
{Py_mod_exec, _sha1_exec},
{0, NULL}
};
static struct PyModuleDef _sha1module = {
PyModuleDef_HEAD_INIT,
.m_name = "_sha1",
.m_size = sizeof(SHA1State),
.m_methods = SHA1_functions,
.m_slots = _sha1_slots,
.m_traverse = _sha1_traverse,
.m_clear = _sha1_clear,
.m_free = _sha1_free
};
PyMODINIT_FUNC
PyInit__sha1(void)
{
return PyModuleDef_Init(&_sha1module);
}