cpython/Modules/sha3module.c

625 lines
18 KiB
C

/* SHA3 module
*
* This module provides an interface to the SHA3 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)
* Gregory P. Smith (greg@krypto.org)
*
* Copyright (C) 2012-2022 Christian Heimes (christian@python.org)
* Licensed to PSF under a Contributor Agreement.
*
*/
#ifndef Py_BUILD_CORE_BUILTIN
# define Py_BUILD_CORE_MODULE 1
#endif
#include "Python.h"
#include "pycore_strhex.h" // _Py_strhex()
#include "pycore_typeobject.h" // _PyType_GetModuleState()
#include "hashlib.h"
#define SHA3_MAX_DIGESTSIZE 64 /* 64 Bytes (512 Bits) for 224 to 512 */
typedef struct {
PyTypeObject *sha3_224_type;
PyTypeObject *sha3_256_type;
PyTypeObject *sha3_384_type;
PyTypeObject *sha3_512_type;
PyTypeObject *shake_128_type;
PyTypeObject *shake_256_type;
} SHA3State;
static inline SHA3State*
sha3_get_state(PyObject *module)
{
void *state = PyModule_GetState(module);
assert(state != NULL);
return (SHA3State *)state;
}
/*[clinic input]
module _sha3
class _sha3.sha3_224 "SHA3object *" "&SHA3_224typ"
class _sha3.sha3_256 "SHA3object *" "&SHA3_256typ"
class _sha3.sha3_384 "SHA3object *" "&SHA3_384typ"
class _sha3.sha3_512 "SHA3object *" "&SHA3_512typ"
class _sha3.shake_128 "SHA3object *" "&SHAKE128type"
class _sha3.shake_256 "SHA3object *" "&SHAKE256type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=b8a53680f370285a]*/
/* The structure for storing SHA3 info */
#include "_hacl/Hacl_Hash_SHA3.h"
typedef struct {
PyObject_HEAD
// Prevents undefined behavior via multiple threads entering the C API.
bool use_mutex;
PyMutex mutex;
Hacl_Streaming_Keccak_state *hash_state;
} SHA3object;
#include "clinic/sha3module.c.h"
static SHA3object *
newSHA3object(PyTypeObject *type)
{
SHA3object *newobj;
newobj = (SHA3object *)PyObject_New(SHA3object, type);
if (newobj == NULL) {
return NULL;
}
HASHLIB_INIT_MUTEX(newobj);
return newobj;
}
static void sha3_update(Hacl_Streaming_Keccak_state *state, uint8_t *buf, Py_ssize_t len) {
/* Note: we explicitly ignore the error code on the basis that it would take >
* 1 billion years to hash more than 2^64 bytes. */
#if PY_SSIZE_T_MAX > UINT32_MAX
while (len > UINT32_MAX) {
Hacl_Streaming_Keccak_update(state, buf, UINT32_MAX);
len -= UINT32_MAX;
buf += UINT32_MAX;
}
#endif
/* Cast to uint32_t is safe: len <= UINT32_MAX at this point. */
Hacl_Streaming_Keccak_update(state, buf, (uint32_t) len);
}
/*[clinic input]
@classmethod
_sha3.sha3_224.__new__ as py_sha3_new
data: object(c_default="NULL") = b''
/
*
usedforsecurity: bool = True
Return a new SHA3 hash object.
[clinic start generated code]*/
static PyObject *
py_sha3_new_impl(PyTypeObject *type, PyObject *data, int usedforsecurity)
/*[clinic end generated code: output=90409addc5d5e8b0 input=637e5f8f6a93982a]*/
{
Py_buffer buf = {NULL, NULL};
SHA3State *state = _PyType_GetModuleState(type);
SHA3object *self = newSHA3object(type);
if (self == NULL) {
goto error;
}
assert(state != NULL);
if (type == state->sha3_224_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_SHA3_224);
} else if (type == state->sha3_256_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_SHA3_256);
} else if (type == state->sha3_384_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_SHA3_384);
} else if (type == state->sha3_512_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_SHA3_512);
} else if (type == state->shake_128_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_Shake128);
} else if (type == state->shake_256_type) {
self->hash_state = Hacl_Streaming_Keccak_malloc(Spec_Hash_Definitions_Shake256);
} else {
PyErr_BadInternalCall();
goto error;
}
if (data) {
GET_BUFFER_VIEW_OR_ERROR(data, &buf, goto error);
if (buf.len >= HASHLIB_GIL_MINSIZE) {
/* We do not initialize self->lock here as this is the constructor
* where it is not yet possible to have concurrent access. */
Py_BEGIN_ALLOW_THREADS
sha3_update(self->hash_state, buf.buf, buf.len);
Py_END_ALLOW_THREADS
} else {
sha3_update(self->hash_state, buf.buf, buf.len);
}
}
PyBuffer_Release(&buf);
return (PyObject *)self;
error:
if (self) {
Py_DECREF(self);
}
if (data && buf.obj) {
PyBuffer_Release(&buf);
}
return NULL;
}
/* Internal methods for a hash object */
static void
SHA3_dealloc(SHA3object *self)
{
Hacl_Streaming_Keccak_free(self->hash_state);
PyTypeObject *tp = Py_TYPE(self);
PyObject_Free(self);
Py_DECREF(tp);
}
/* External methods for a hash object */
/*[clinic input]
_sha3.sha3_224.copy
Return a copy of the hash object.
[clinic start generated code]*/
static PyObject *
_sha3_sha3_224_copy_impl(SHA3object *self)
/*[clinic end generated code: output=6c537411ecdcda4c input=93a44aaebea51ba8]*/
{
SHA3object *newobj;
if ((newobj = newSHA3object(Py_TYPE(self))) == NULL) {
return NULL;
}
ENTER_HASHLIB(self);
newobj->hash_state = Hacl_Streaming_Keccak_copy(self->hash_state);
LEAVE_HASHLIB(self);
return (PyObject *)newobj;
}
/*[clinic input]
_sha3.sha3_224.digest
Return the digest value as a bytes object.
[clinic start generated code]*/
static PyObject *
_sha3_sha3_224_digest_impl(SHA3object *self)
/*[clinic end generated code: output=fd531842e20b2d5b input=5b2a659536bbd248]*/
{
unsigned char digest[SHA3_MAX_DIGESTSIZE];
// This function errors out if the algorithm is Shake. Here, we know this
// not to be the case, and therefore do not perform error checking.
ENTER_HASHLIB(self);
Hacl_Streaming_Keccak_finish(self->hash_state, digest);
LEAVE_HASHLIB(self);
return PyBytes_FromStringAndSize((const char *)digest,
Hacl_Streaming_Keccak_hash_len(self->hash_state));
}
/*[clinic input]
_sha3.sha3_224.hexdigest
Return the digest value as a string of hexadecimal digits.
[clinic start generated code]*/
static PyObject *
_sha3_sha3_224_hexdigest_impl(SHA3object *self)
/*[clinic end generated code: output=75ad03257906918d input=2d91bb6e0d114ee3]*/
{
unsigned char digest[SHA3_MAX_DIGESTSIZE];
ENTER_HASHLIB(self);
Hacl_Streaming_Keccak_finish(self->hash_state, digest);
LEAVE_HASHLIB(self);
return _Py_strhex((const char *)digest,
Hacl_Streaming_Keccak_hash_len(self->hash_state));
}
/*[clinic input]
_sha3.sha3_224.update
data: object
/
Update this hash object's state with the provided bytes-like object.
[clinic start generated code]*/
static PyObject *
_sha3_sha3_224_update(SHA3object *self, PyObject *data)
/*[clinic end generated code: output=d3223352286ed357 input=a887f54dcc4ae227]*/
{
Py_buffer buf;
GET_BUFFER_VIEW_OR_ERROUT(data, &buf);
if (!self->use_mutex && buf.len >= HASHLIB_GIL_MINSIZE) {
self->use_mutex = true;
}
if (self->use_mutex) {
Py_BEGIN_ALLOW_THREADS
PyMutex_Lock(&self->mutex);
sha3_update(self->hash_state, buf.buf, buf.len);
PyMutex_Unlock(&self->mutex);
Py_END_ALLOW_THREADS
} else {
sha3_update(self->hash_state, buf.buf, buf.len);
}
PyBuffer_Release(&buf);
Py_RETURN_NONE;
}
static PyMethodDef SHA3_methods[] = {
_SHA3_SHA3_224_COPY_METHODDEF
_SHA3_SHA3_224_DIGEST_METHODDEF
_SHA3_SHA3_224_HEXDIGEST_METHODDEF
_SHA3_SHA3_224_UPDATE_METHODDEF
{NULL, NULL} /* sentinel */
};
static PyObject *
SHA3_get_block_size(SHA3object *self, void *closure)
{
uint32_t rate = Hacl_Streaming_Keccak_block_len(self->hash_state);
return PyLong_FromLong(rate);
}
static PyObject *
SHA3_get_name(SHA3object *self, void *closure)
{
PyTypeObject *type = Py_TYPE(self);
SHA3State *state = _PyType_GetModuleState(type);
assert(state != NULL);
if (type == state->sha3_224_type) {
return PyUnicode_FromString("sha3_224");
} else if (type == state->sha3_256_type) {
return PyUnicode_FromString("sha3_256");
} else if (type == state->sha3_384_type) {
return PyUnicode_FromString("sha3_384");
} else if (type == state->sha3_512_type) {
return PyUnicode_FromString("sha3_512");
} else if (type == state->shake_128_type) {
return PyUnicode_FromString("shake_128");
} else if (type == state->shake_256_type) {
return PyUnicode_FromString("shake_256");
} else {
PyErr_BadInternalCall();
return NULL;
}
}
static PyObject *
SHA3_get_digest_size(SHA3object *self, void *closure)
{
// Preserving previous behavior: variable-length algorithms return 0
if (Hacl_Streaming_Keccak_is_shake(self->hash_state))
return PyLong_FromLong(0);
else
return PyLong_FromLong(Hacl_Streaming_Keccak_hash_len(self->hash_state));
}
static PyObject *
SHA3_get_capacity_bits(SHA3object *self, void *closure)
{
uint32_t rate = Hacl_Streaming_Keccak_block_len(self->hash_state) * 8;
int capacity = 1600 - rate;
return PyLong_FromLong(capacity);
}
static PyObject *
SHA3_get_rate_bits(SHA3object *self, void *closure)
{
uint32_t rate = Hacl_Streaming_Keccak_block_len(self->hash_state) * 8;
return PyLong_FromLong(rate);
}
static PyObject *
SHA3_get_suffix(SHA3object *self, void *closure)
{
unsigned char suffix[2] = {0x06, 0};
return PyBytes_FromStringAndSize((const char *)suffix, 1);
}
static PyGetSetDef SHA3_getseters[] = {
{"block_size", (getter)SHA3_get_block_size, NULL, NULL, NULL},
{"name", (getter)SHA3_get_name, NULL, NULL, NULL},
{"digest_size", (getter)SHA3_get_digest_size, NULL, NULL, NULL},
{"_capacity_bits", (getter)SHA3_get_capacity_bits, NULL, NULL, NULL},
{"_rate_bits", (getter)SHA3_get_rate_bits, NULL, NULL, NULL},
{"_suffix", (getter)SHA3_get_suffix, NULL, NULL, NULL},
{NULL} /* Sentinel */
};
#define SHA3_TYPE_SLOTS(type_slots_obj, type_doc, type_methods, type_getseters) \
static PyType_Slot type_slots_obj[] = { \
{Py_tp_dealloc, SHA3_dealloc}, \
{Py_tp_doc, (char*)type_doc}, \
{Py_tp_methods, type_methods}, \
{Py_tp_getset, type_getseters}, \
{Py_tp_new, py_sha3_new}, \
{0,0} \
}
// Using _PyType_GetModuleState() on these types is safe since they
// cannot be subclassed: it does not have the Py_TPFLAGS_BASETYPE flag.
#define SHA3_TYPE_SPEC(type_spec_obj, type_name, type_slots) \
static PyType_Spec type_spec_obj = { \
.name = "_sha3." type_name, \
.basicsize = sizeof(SHA3object), \
.flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_IMMUTABLETYPE, \
.slots = type_slots \
}
PyDoc_STRVAR(sha3_224__doc__,
"sha3_224([data], *, usedforsecurity=True) -> SHA3 object\n\
\n\
Return a new SHA3 hash object with a hashbit length of 28 bytes.");
PyDoc_STRVAR(sha3_256__doc__,
"sha3_256([data], *, usedforsecurity=True) -> SHA3 object\n\
\n\
Return a new SHA3 hash object with a hashbit length of 32 bytes.");
PyDoc_STRVAR(sha3_384__doc__,
"sha3_384([data], *, usedforsecurity=True) -> SHA3 object\n\
\n\
Return a new SHA3 hash object with a hashbit length of 48 bytes.");
PyDoc_STRVAR(sha3_512__doc__,
"sha3_512([data], *, usedforsecurity=True) -> SHA3 object\n\
\n\
Return a new SHA3 hash object with a hashbit length of 64 bytes.");
SHA3_TYPE_SLOTS(sha3_224_slots, sha3_224__doc__, SHA3_methods, SHA3_getseters);
SHA3_TYPE_SPEC(sha3_224_spec, "sha3_224", sha3_224_slots);
SHA3_TYPE_SLOTS(sha3_256_slots, sha3_256__doc__, SHA3_methods, SHA3_getseters);
SHA3_TYPE_SPEC(sha3_256_spec, "sha3_256", sha3_256_slots);
SHA3_TYPE_SLOTS(sha3_384_slots, sha3_384__doc__, SHA3_methods, SHA3_getseters);
SHA3_TYPE_SPEC(sha3_384_spec, "sha3_384", sha3_384_slots);
SHA3_TYPE_SLOTS(sha3_512_slots, sha3_512__doc__, SHA3_methods, SHA3_getseters);
SHA3_TYPE_SPEC(sha3_512_spec, "sha3_512", sha3_512_slots);
static PyObject *
_SHAKE_digest(SHA3object *self, unsigned long digestlen, int hex)
{
unsigned char *digest = NULL;
PyObject *result = NULL;
if (digestlen >= (1 << 29)) {
PyErr_SetString(PyExc_ValueError, "length is too large");
return NULL;
}
digest = (unsigned char*)PyMem_Malloc(digestlen);
if (digest == NULL) {
return PyErr_NoMemory();
}
/* Get the raw (binary) digest value. The HACL functions errors out if:
* - the algorith is not shake -- not the case here
* - the output length is zero -- we follow the existing behavior and return
* an empty digest, without raising an error */
if (digestlen > 0) {
Hacl_Streaming_Keccak_squeeze(self->hash_state, digest, digestlen);
}
if (hex) {
result = _Py_strhex((const char *)digest, digestlen);
} else {
result = PyBytes_FromStringAndSize((const char *)digest,
digestlen);
}
if (digest != NULL) {
PyMem_Free(digest);
}
return result;
}
/*[clinic input]
_sha3.shake_128.digest
length: unsigned_long
/
Return the digest value as a bytes object.
[clinic start generated code]*/
static PyObject *
_sha3_shake_128_digest_impl(SHA3object *self, unsigned long length)
/*[clinic end generated code: output=2313605e2f87bb8f input=418ef6a36d2e6082]*/
{
return _SHAKE_digest(self, length, 0);
}
/*[clinic input]
_sha3.shake_128.hexdigest
length: unsigned_long
/
Return the digest value as a string of hexadecimal digits.
[clinic start generated code]*/
static PyObject *
_sha3_shake_128_hexdigest_impl(SHA3object *self, unsigned long length)
/*[clinic end generated code: output=bf8e2f1e490944a8 input=69fb29b0926ae321]*/
{
return _SHAKE_digest(self, length, 1);
}
static PyObject *
SHAKE_get_digest_size(SHA3object *self, void *closure)
{
return PyLong_FromLong(0);
}
static PyObject *
SHAKE_get_suffix(SHA3object *self, void *closure)
{
unsigned char suffix[2] = {0x1f, 0};
return PyBytes_FromStringAndSize((const char *)suffix, 1);
}
static PyGetSetDef SHAKE_getseters[] = {
{"block_size", (getter)SHA3_get_block_size, NULL, NULL, NULL},
{"name", (getter)SHA3_get_name, NULL, NULL, NULL},
{"digest_size", (getter)SHAKE_get_digest_size, NULL, NULL, NULL},
{"_capacity_bits", (getter)SHA3_get_capacity_bits, NULL, NULL, NULL},
{"_rate_bits", (getter)SHA3_get_rate_bits, NULL, NULL, NULL},
{"_suffix", (getter)SHAKE_get_suffix, NULL, NULL, NULL},
{NULL} /* Sentinel */
};
static PyMethodDef SHAKE_methods[] = {
_SHA3_SHA3_224_COPY_METHODDEF
_SHA3_SHAKE_128_DIGEST_METHODDEF
_SHA3_SHAKE_128_HEXDIGEST_METHODDEF
_SHA3_SHA3_224_UPDATE_METHODDEF
{NULL, NULL} /* sentinel */
};
PyDoc_STRVAR(shake_128__doc__,
"shake_128([data], *, usedforsecurity=True) -> SHAKE object\n\
\n\
Return a new SHAKE hash object.");
PyDoc_STRVAR(shake_256__doc__,
"shake_256([data], *, usedforsecurity=True) -> SHAKE object\n\
\n\
Return a new SHAKE hash object.");
SHA3_TYPE_SLOTS(SHAKE128slots, shake_128__doc__, SHAKE_methods, SHAKE_getseters);
SHA3_TYPE_SPEC(SHAKE128_spec, "shake_128", SHAKE128slots);
SHA3_TYPE_SLOTS(SHAKE256slots, shake_256__doc__, SHAKE_methods, SHAKE_getseters);
SHA3_TYPE_SPEC(SHAKE256_spec, "shake_256", SHAKE256slots);
static int
_sha3_traverse(PyObject *module, visitproc visit, void *arg)
{
SHA3State *state = sha3_get_state(module);
Py_VISIT(state->sha3_224_type);
Py_VISIT(state->sha3_256_type);
Py_VISIT(state->sha3_384_type);
Py_VISIT(state->sha3_512_type);
Py_VISIT(state->shake_128_type);
Py_VISIT(state->shake_256_type);
return 0;
}
static int
_sha3_clear(PyObject *module)
{
SHA3State *state = sha3_get_state(module);
Py_CLEAR(state->sha3_224_type);
Py_CLEAR(state->sha3_256_type);
Py_CLEAR(state->sha3_384_type);
Py_CLEAR(state->sha3_512_type);
Py_CLEAR(state->shake_128_type);
Py_CLEAR(state->shake_256_type);
return 0;
}
static void
_sha3_free(void *module)
{
_sha3_clear((PyObject *)module);
}
static int
_sha3_exec(PyObject *m)
{
SHA3State *st = sha3_get_state(m);
#define init_sha3type(type, typespec) \
do { \
st->type = (PyTypeObject *)PyType_FromModuleAndSpec( \
m, &typespec, NULL); \
if (st->type == NULL) { \
return -1; \
} \
if (PyModule_AddType(m, st->type) < 0) { \
return -1; \
} \
} while(0)
init_sha3type(sha3_224_type, sha3_224_spec);
init_sha3type(sha3_256_type, sha3_256_spec);
init_sha3type(sha3_384_type, sha3_384_spec);
init_sha3type(sha3_512_type, sha3_512_spec);
init_sha3type(shake_128_type, SHAKE128_spec);
init_sha3type(shake_256_type, SHAKE256_spec);
#undef init_sha3type
if (PyModule_AddStringConstant(m, "implementation",
"HACL") < 0) {
return -1;
}
return 0;
}
static PyModuleDef_Slot _sha3_slots[] = {
{Py_mod_exec, _sha3_exec},
{Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
{0, NULL}
};
/* Initialize this module. */
static struct PyModuleDef _sha3module = {
PyModuleDef_HEAD_INIT,
.m_name = "_sha3",
.m_size = sizeof(SHA3State),
.m_slots = _sha3_slots,
.m_traverse = _sha3_traverse,
.m_clear = _sha3_clear,
.m_free = _sha3_free,
};
PyMODINIT_FUNC
PyInit__sha3(void)
{
return PyModuleDef_Init(&_sha3module);
}