cpython/Modules/md5module.c
2021-02-12 02:34:11 -08:00

610 lines
15 KiB
C

/* MD5 module */
/* This module provides an interface to the MD5 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.
*/
/* MD5 objects */
#include "Python.h"
#include "hashlib.h"
#include "pystrhex.h"
/*[clinic input]
module _md5
class MD5Type "MD5object *" "&PyType_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=6e5261719957a912]*/
/* Some useful types */
#if SIZEOF_INT == 4
typedef unsigned int MD5_INT32; /* 32-bit integer */
typedef long long MD5_INT64; /* 64-bit integer */
#else
/* not defined. compilation will die. */
#endif
/* The MD5 block size and message digest sizes, in bytes */
#define MD5_BLOCKSIZE 64
#define MD5_DIGESTSIZE 16
/* The structure for storing MD5 info */
struct md5_state {
MD5_INT64 length;
MD5_INT32 state[4], curlen;
unsigned char buf[MD5_BLOCKSIZE];
};
typedef struct {
PyObject_HEAD
struct md5_state hash_state;
} MD5object;
#include "clinic/md5module.c.h"
/* ------------------------------------------------------------------------
*
* This code for the MD5 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 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 STORE32L(x, y) \
{ (y)[3] = (unsigned char)(((x)>>24)&255); (y)[2] = (unsigned char)(((x)>>16)&255); \
(y)[1] = (unsigned char)(((x)>>8)&255); (y)[0] = (unsigned char)((x)&255); }
#define LOAD32L(x, y) \
{ x = ((unsigned long)((y)[3] & 255)<<24) | \
((unsigned long)((y)[2] & 255)<<16) | \
((unsigned long)((y)[1] & 255)<<8) | \
((unsigned long)((y)[0] & 255)); }
#define STORE64L(x, y) \
{ (y)[7] = (unsigned char)(((x)>>56)&255); (y)[6] = (unsigned char)(((x)>>48)&255); \
(y)[5] = (unsigned char)(((x)>>40)&255); (y)[4] = (unsigned char)(((x)>>32)&255); \
(y)[3] = (unsigned char)(((x)>>24)&255); (y)[2] = (unsigned char)(((x)>>16)&255); \
(y)[1] = (unsigned char)(((x)>>8)&255); (y)[0] = (unsigned char)((x)&255); }
/* MD5 macros */
#define F(x,y,z) (z ^ (x & (y ^ z)))
#define G(x,y,z) (y ^ (z & (y ^ x)))
#define H(x,y,z) (x^y^z)
#define I(x,y,z) (y^(x|(~z)))
#define FF(a,b,c,d,M,s,t) \
a = (a + F(b,c,d) + M + t); a = ROLc(a, s) + b;
#define GG(a,b,c,d,M,s,t) \
a = (a + G(b,c,d) + M + t); a = ROLc(a, s) + b;
#define HH(a,b,c,d,M,s,t) \
a = (a + H(b,c,d) + M + t); a = ROLc(a, s) + b;
#define II(a,b,c,d,M,s,t) \
a = (a + I(b,c,d) + M + t); a = ROLc(a, s) + b;
static void md5_compress(struct md5_state *md5, const unsigned char *buf)
{
MD5_INT32 i, W[16], a, b, c, d;
assert(md5 != NULL);
assert(buf != NULL);
/* copy the state into 512-bits into W[0..15] */
for (i = 0; i < 16; i++) {
LOAD32L(W[i], buf + (4*i));
}
/* copy state */
a = md5->state[0];
b = md5->state[1];
c = md5->state[2];
d = md5->state[3];
FF(a,b,c,d,W[0],7,0xd76aa478UL)
FF(d,a,b,c,W[1],12,0xe8c7b756UL)
FF(c,d,a,b,W[2],17,0x242070dbUL)
FF(b,c,d,a,W[3],22,0xc1bdceeeUL)
FF(a,b,c,d,W[4],7,0xf57c0fafUL)
FF(d,a,b,c,W[5],12,0x4787c62aUL)
FF(c,d,a,b,W[6],17,0xa8304613UL)
FF(b,c,d,a,W[7],22,0xfd469501UL)
FF(a,b,c,d,W[8],7,0x698098d8UL)
FF(d,a,b,c,W[9],12,0x8b44f7afUL)
FF(c,d,a,b,W[10],17,0xffff5bb1UL)
FF(b,c,d,a,W[11],22,0x895cd7beUL)
FF(a,b,c,d,W[12],7,0x6b901122UL)
FF(d,a,b,c,W[13],12,0xfd987193UL)
FF(c,d,a,b,W[14],17,0xa679438eUL)
FF(b,c,d,a,W[15],22,0x49b40821UL)
GG(a,b,c,d,W[1],5,0xf61e2562UL)
GG(d,a,b,c,W[6],9,0xc040b340UL)
GG(c,d,a,b,W[11],14,0x265e5a51UL)
GG(b,c,d,a,W[0],20,0xe9b6c7aaUL)
GG(a,b,c,d,W[5],5,0xd62f105dUL)
GG(d,a,b,c,W[10],9,0x02441453UL)
GG(c,d,a,b,W[15],14,0xd8a1e681UL)
GG(b,c,d,a,W[4],20,0xe7d3fbc8UL)
GG(a,b,c,d,W[9],5,0x21e1cde6UL)
GG(d,a,b,c,W[14],9,0xc33707d6UL)
GG(c,d,a,b,W[3],14,0xf4d50d87UL)
GG(b,c,d,a,W[8],20,0x455a14edUL)
GG(a,b,c,d,W[13],5,0xa9e3e905UL)
GG(d,a,b,c,W[2],9,0xfcefa3f8UL)
GG(c,d,a,b,W[7],14,0x676f02d9UL)
GG(b,c,d,a,W[12],20,0x8d2a4c8aUL)
HH(a,b,c,d,W[5],4,0xfffa3942UL)
HH(d,a,b,c,W[8],11,0x8771f681UL)
HH(c,d,a,b,W[11],16,0x6d9d6122UL)
HH(b,c,d,a,W[14],23,0xfde5380cUL)
HH(a,b,c,d,W[1],4,0xa4beea44UL)
HH(d,a,b,c,W[4],11,0x4bdecfa9UL)
HH(c,d,a,b,W[7],16,0xf6bb4b60UL)
HH(b,c,d,a,W[10],23,0xbebfbc70UL)
HH(a,b,c,d,W[13],4,0x289b7ec6UL)
HH(d,a,b,c,W[0],11,0xeaa127faUL)
HH(c,d,a,b,W[3],16,0xd4ef3085UL)
HH(b,c,d,a,W[6],23,0x04881d05UL)
HH(a,b,c,d,W[9],4,0xd9d4d039UL)
HH(d,a,b,c,W[12],11,0xe6db99e5UL)
HH(c,d,a,b,W[15],16,0x1fa27cf8UL)
HH(b,c,d,a,W[2],23,0xc4ac5665UL)
II(a,b,c,d,W[0],6,0xf4292244UL)
II(d,a,b,c,W[7],10,0x432aff97UL)
II(c,d,a,b,W[14],15,0xab9423a7UL)
II(b,c,d,a,W[5],21,0xfc93a039UL)
II(a,b,c,d,W[12],6,0x655b59c3UL)
II(d,a,b,c,W[3],10,0x8f0ccc92UL)
II(c,d,a,b,W[10],15,0xffeff47dUL)
II(b,c,d,a,W[1],21,0x85845dd1UL)
II(a,b,c,d,W[8],6,0x6fa87e4fUL)
II(d,a,b,c,W[15],10,0xfe2ce6e0UL)
II(c,d,a,b,W[6],15,0xa3014314UL)
II(b,c,d,a,W[13],21,0x4e0811a1UL)
II(a,b,c,d,W[4],6,0xf7537e82UL)
II(d,a,b,c,W[11],10,0xbd3af235UL)
II(c,d,a,b,W[2],15,0x2ad7d2bbUL)
II(b,c,d,a,W[9],21,0xeb86d391UL)
md5->state[0] = md5->state[0] + a;
md5->state[1] = md5->state[1] + b;
md5->state[2] = md5->state[2] + c;
md5->state[3] = md5->state[3] + d;
}
/**
Initialize the hash state
@param md5 The hash state you wish to initialize
*/
static void
md5_init(struct md5_state *md5)
{
assert(md5 != NULL);
md5->state[0] = 0x67452301UL;
md5->state[1] = 0xefcdab89UL;
md5->state[2] = 0x98badcfeUL;
md5->state[3] = 0x10325476UL;
md5->curlen = 0;
md5->length = 0;
}
/**
Process a block of memory though the hash
@param md5 The hash state
@param in The data to hash
@param inlen The length of the data (octets)
*/
static void
md5_process(struct md5_state *md5, const unsigned char *in, Py_ssize_t inlen)
{
Py_ssize_t n;
assert(md5 != NULL);
assert(in != NULL);
assert(md5->curlen <= sizeof(md5->buf));
while (inlen > 0) {
if (md5->curlen == 0 && inlen >= MD5_BLOCKSIZE) {
md5_compress(md5, in);
md5->length += MD5_BLOCKSIZE * 8;
in += MD5_BLOCKSIZE;
inlen -= MD5_BLOCKSIZE;
} else {
n = Py_MIN(inlen, (Py_ssize_t)(MD5_BLOCKSIZE - md5->curlen));
memcpy(md5->buf + md5->curlen, in, (size_t)n);
md5->curlen += (MD5_INT32)n;
in += n;
inlen -= n;
if (md5->curlen == MD5_BLOCKSIZE) {
md5_compress(md5, md5->buf);
md5->length += 8*MD5_BLOCKSIZE;
md5->curlen = 0;
}
}
}
}
/**
Terminate the hash to get the digest
@param md5 The hash state
@param out [out] The destination of the hash (16 bytes)
*/
static void
md5_done(struct md5_state *md5, unsigned char *out)
{
int i;
assert(md5 != NULL);
assert(out != NULL);
assert(md5->curlen < sizeof(md5->buf));
/* increase the length of the message */
md5->length += md5->curlen * 8;
/* append the '1' bit */
md5->buf[md5->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 (md5->curlen > 56) {
while (md5->curlen < 64) {
md5->buf[md5->curlen++] = (unsigned char)0;
}
md5_compress(md5, md5->buf);
md5->curlen = 0;
}
/* pad up to 56 bytes of zeroes */
while (md5->curlen < 56) {
md5->buf[md5->curlen++] = (unsigned char)0;
}
/* store length */
STORE64L(md5->length, md5->buf+56);
md5_compress(md5, md5->buf);
/* copy output */
for (i = 0; i < 4; i++) {
STORE32L(md5->state[i], out+(4*i));
}
}
/* .Source: /cvs/libtom/libtomcrypt/src/hashes/md5.c,v $ */
/* .Revision: 1.10 $ */
/* .Date: 2007/05/12 14:25:28 $ */
/*
* End of copied MD5 code.
*
* ------------------------------------------------------------------------
*/
typedef struct {
PyTypeObject* md5_type;
} MD5State;
static inline MD5State*
md5_get_state(PyObject *module)
{
void *state = PyModule_GetState(module);
assert(state != NULL);
return (MD5State *)state;
}
static MD5object *
newMD5object(MD5State * st)
{
return (MD5object *)PyObject_New(MD5object, st->md5_type);
}
/* Internal methods for a hash object */
static void
MD5_dealloc(PyObject *ptr)
{
PyTypeObject *tp = Py_TYPE(ptr);
PyObject_Free(ptr);
Py_DECREF(tp);
}
/* External methods for a hash object */
/*[clinic input]
MD5Type.copy
cls: defining_class
Return a copy of the hash object.
[clinic start generated code]*/
static PyObject *
MD5Type_copy_impl(MD5object *self, PyTypeObject *cls)
/*[clinic end generated code: output=bf055e08244bf5ee input=d89087dcfb2a8620]*/
{
MD5State *st = PyType_GetModuleState(cls);
MD5object *newobj;
if ((newobj = newMD5object(st))==NULL)
return NULL;
newobj->hash_state = self->hash_state;
return (PyObject *)newobj;
}
/*[clinic input]
MD5Type.digest
Return the digest value as a bytes object.
[clinic start generated code]*/
static PyObject *
MD5Type_digest_impl(MD5object *self)
/*[clinic end generated code: output=eb691dc4190a07ec input=bc0c4397c2994be6]*/
{
unsigned char digest[MD5_DIGESTSIZE];
struct md5_state temp;
temp = self->hash_state;
md5_done(&temp, digest);
return PyBytes_FromStringAndSize((const char *)digest, MD5_DIGESTSIZE);
}
/*[clinic input]
MD5Type.hexdigest
Return the digest value as a string of hexadecimal digits.
[clinic start generated code]*/
static PyObject *
MD5Type_hexdigest_impl(MD5object *self)
/*[clinic end generated code: output=17badced1f3ac932 input=b60b19de644798dd]*/
{
unsigned char digest[MD5_DIGESTSIZE];
struct md5_state temp;
/* Get the raw (binary) digest value */
temp = self->hash_state;
md5_done(&temp, digest);
return _Py_strhex((const char*)digest, MD5_DIGESTSIZE);
}
/*[clinic input]
MD5Type.update
obj: object
/
Update this hash object's state with the provided string.
[clinic start generated code]*/
static PyObject *
MD5Type_update(MD5object *self, PyObject *obj)
/*[clinic end generated code: output=f6ad168416338423 input=6e1efcd9ecf17032]*/
{
Py_buffer buf;
GET_BUFFER_VIEW_OR_ERROUT(obj, &buf);
md5_process(&self->hash_state, buf.buf, buf.len);
PyBuffer_Release(&buf);
Py_RETURN_NONE;
}
static PyMethodDef MD5_methods[] = {
MD5TYPE_COPY_METHODDEF
MD5TYPE_DIGEST_METHODDEF
MD5TYPE_HEXDIGEST_METHODDEF
MD5TYPE_UPDATE_METHODDEF
{NULL, NULL} /* sentinel */
};
static PyObject *
MD5_get_block_size(PyObject *self, void *closure)
{
return PyLong_FromLong(MD5_BLOCKSIZE);
}
static PyObject *
MD5_get_name(PyObject *self, void *closure)
{
return PyUnicode_FromStringAndSize("md5", 3);
}
static PyObject *
md5_get_digest_size(PyObject *self, void *closure)
{
return PyLong_FromLong(MD5_DIGESTSIZE);
}
static PyGetSetDef MD5_getseters[] = {
{"block_size",
(getter)MD5_get_block_size, NULL,
NULL,
NULL},
{"name",
(getter)MD5_get_name, NULL,
NULL,
NULL},
{"digest_size",
(getter)md5_get_digest_size, NULL,
NULL,
NULL},
{NULL} /* Sentinel */
};
static PyType_Slot md5_type_slots[] = {
{Py_tp_dealloc, MD5_dealloc},
{Py_tp_methods, MD5_methods},
{Py_tp_getset, MD5_getseters},
{0,0}
};
static PyType_Spec md5_type_spec = {
.name = "_md5.md5",
.basicsize = sizeof(MD5object),
.flags = Py_TPFLAGS_DEFAULT,
.slots = md5_type_slots
};
/* The single module-level function: new() */
/*[clinic input]
_md5.md5
string: object(c_default="NULL") = b''
*
usedforsecurity: bool = True
Return a new MD5 hash object; optionally initialized with a string.
[clinic start generated code]*/
static PyObject *
_md5_md5_impl(PyObject *module, PyObject *string, int usedforsecurity)
/*[clinic end generated code: output=587071f76254a4ac input=7a144a1905636985]*/
{
MD5object *new;
Py_buffer buf;
if (string)
GET_BUFFER_VIEW_OR_ERROUT(string, &buf);
MD5State *st = md5_get_state(module);
if ((new = newMD5object(st)) == NULL) {
if (string)
PyBuffer_Release(&buf);
return NULL;
}
md5_init(&new->hash_state);
if (PyErr_Occurred()) {
Py_DECREF(new);
if (string)
PyBuffer_Release(&buf);
return NULL;
}
if (string) {
md5_process(&new->hash_state, buf.buf, buf.len);
PyBuffer_Release(&buf);
}
return (PyObject *)new;
}
/* List of functions exported by this module */
static struct PyMethodDef MD5_functions[] = {
_MD5_MD5_METHODDEF
{NULL, NULL} /* Sentinel */
};
static int
_md5_traverse(PyObject *module, visitproc visit, void *arg)
{
MD5State *state = md5_get_state(module);
Py_VISIT(state->md5_type);
return 0;
}
static int
_md5_clear(PyObject *module)
{
MD5State *state = md5_get_state(module);
Py_CLEAR(state->md5_type);
return 0;
}
static void
_md5_free(void *module)
{
_md5_clear((PyObject *)module);
}
/* Initialize this module. */
static int
md5_exec(PyObject *m)
{
MD5State *st = md5_get_state(m);
st->md5_type = (PyTypeObject *)PyType_FromModuleAndSpec(
m, &md5_type_spec, NULL);
if (st->md5_type == NULL) {
return -1;
}
Py_INCREF((PyObject *)st->md5_type);
if (PyModule_AddObject(m, "MD5Type", (PyObject *)st->md5_type) < 0) {
Py_DECREF(st->md5_type);
return -1;
}
return 0;
}
static PyModuleDef_Slot _md5_slots[] = {
{Py_mod_exec, md5_exec},
{0, NULL}
};
static struct PyModuleDef _md5module = {
PyModuleDef_HEAD_INIT,
.m_name = "_md5",
.m_size = sizeof(MD5State),
.m_methods = MD5_functions,
.m_slots = _md5_slots,
.m_traverse = _md5_traverse,
.m_clear = _md5_clear,
.m_free = _md5_free,
};
PyMODINIT_FUNC
PyInit__md5(void)
{
return PyModuleDef_Init(&_md5module);
}