ref: 196da4ec6f429683a351312d1f0bcb05847e7f89
dir: /sys/src/cmd/python/Modules/_hashopenssl.c/
/* Module that wraps all OpenSSL hash algorithms */ /* * Copyright (C) 2005 Gregory P. Smith ([email protected]) * Licensed to PSF under a Contributor Agreement. * * Derived from a skeleton of shamodule.c containing work performed by: * * Andrew Kuchling ([email protected]) * Greg Stein ([email protected]) * */ #define PY_SSIZE_T_CLEAN #include "Python.h" #include "structmember.h" /* EVP is the preferred interface to hashing in OpenSSL */ #include <openssl/evp.h> #ifndef HASH_OBJ_CONSTRUCTOR #define HASH_OBJ_CONSTRUCTOR 0 #endif typedef struct { PyObject_HEAD PyObject *name; /* name of this hash algorithm */ EVP_MD_CTX ctx; /* OpenSSL message digest context */ } EVPobject; static PyTypeObject EVPtype; #define DEFINE_CONSTS_FOR_NEW(Name) \ static PyObject *CONST_ ## Name ## _name_obj; \ static EVP_MD_CTX CONST_new_ ## Name ## _ctx; \ static EVP_MD_CTX *CONST_new_ ## Name ## _ctx_p = NULL; DEFINE_CONSTS_FOR_NEW(md5) DEFINE_CONSTS_FOR_NEW(sha1) DEFINE_CONSTS_FOR_NEW(sha224) DEFINE_CONSTS_FOR_NEW(sha256) DEFINE_CONSTS_FOR_NEW(sha384) DEFINE_CONSTS_FOR_NEW(sha512) static EVPobject * newEVPobject(PyObject *name) { EVPobject *retval = (EVPobject *)PyObject_New(EVPobject, &EVPtype); /* save the name for .name to return */ if (retval != NULL) { Py_INCREF(name); retval->name = name; } return retval; } /* Internal methods for a hash object */ static void EVP_dealloc(PyObject *ptr) { EVP_MD_CTX_cleanup(&((EVPobject *)ptr)->ctx); Py_XDECREF(((EVPobject *)ptr)->name); PyObject_Del(ptr); } /* External methods for a hash object */ PyDoc_STRVAR(EVP_copy__doc__, "Return a copy of the hash object."); static PyObject * EVP_copy(EVPobject *self, PyObject *unused) { EVPobject *newobj; if ( (newobj = newEVPobject(self->name))==NULL) return NULL; EVP_MD_CTX_copy(&newobj->ctx, &self->ctx); return (PyObject *)newobj; } PyDoc_STRVAR(EVP_digest__doc__, "Return the digest value as a string of binary data."); static PyObject * EVP_digest(EVPobject *self, PyObject *unused) { unsigned char digest[EVP_MAX_MD_SIZE]; EVP_MD_CTX temp_ctx; PyObject *retval; unsigned int digest_size; EVP_MD_CTX_copy(&temp_ctx, &self->ctx); digest_size = EVP_MD_CTX_size(&temp_ctx); EVP_DigestFinal(&temp_ctx, digest, NULL); retval = PyString_FromStringAndSize((const char *)digest, digest_size); EVP_MD_CTX_cleanup(&temp_ctx); return retval; } PyDoc_STRVAR(EVP_hexdigest__doc__, "Return the digest value as a string of hexadecimal digits."); static PyObject * EVP_hexdigest(EVPobject *self, PyObject *unused) { unsigned char digest[EVP_MAX_MD_SIZE]; EVP_MD_CTX temp_ctx; PyObject *retval; char *hex_digest; unsigned int i, j, digest_size; /* Get the raw (binary) digest value */ EVP_MD_CTX_copy(&temp_ctx, &self->ctx); digest_size = EVP_MD_CTX_size(&temp_ctx); EVP_DigestFinal(&temp_ctx, digest, NULL); EVP_MD_CTX_cleanup(&temp_ctx); /* Create a new string */ /* NOTE: not thread safe! modifying an already created string object */ /* (not a problem because we hold the GIL by default) */ retval = PyString_FromStringAndSize(NULL, digest_size * 2); if (!retval) return NULL; hex_digest = PyString_AsString(retval); if (!hex_digest) { Py_DECREF(retval); return NULL; } /* Make hex version of the digest */ for(i=j=0; i<digest_size; 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(EVP_update__doc__, "Update this hash object's state with the provided string."); static PyObject * EVP_update(EVPobject *self, PyObject *args) { unsigned char *cp; Py_ssize_t len; if (!PyArg_ParseTuple(args, "s#:update", &cp, &len)) return NULL; EVP_DigestUpdate(&self->ctx, cp, Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int)); Py_INCREF(Py_None); return Py_None; } static PyMethodDef EVP_methods[] = { {"update", (PyCFunction)EVP_update, METH_VARARGS, EVP_update__doc__}, {"digest", (PyCFunction)EVP_digest, METH_NOARGS, EVP_digest__doc__}, {"hexdigest", (PyCFunction)EVP_hexdigest, METH_NOARGS, EVP_hexdigest__doc__}, {"copy", (PyCFunction)EVP_copy, METH_NOARGS, EVP_copy__doc__}, {NULL, NULL} /* sentinel */ }; static PyObject * EVP_get_block_size(EVPobject *self, void *closure) { return PyInt_FromLong(EVP_MD_CTX_block_size(&((EVPobject *)self)->ctx)); } static PyObject * EVP_get_digest_size(EVPobject *self, void *closure) { return PyInt_FromLong(EVP_MD_CTX_size(&((EVPobject *)self)->ctx)); } static PyMemberDef EVP_members[] = { {"name", T_OBJECT, offsetof(EVPobject, name), READONLY, PyDoc_STR("algorithm name.")}, {NULL} /* Sentinel */ }; static PyGetSetDef EVP_getseters[] = { {"digest_size", (getter)EVP_get_digest_size, NULL, NULL, NULL}, {"block_size", (getter)EVP_get_block_size, NULL, NULL, NULL}, /* the old md5 and sha modules support 'digest_size' as in PEP 247. * the old sha module also supported 'digestsize'. ugh. */ {"digestsize", (getter)EVP_get_digest_size, NULL, NULL, NULL}, {NULL} /* Sentinel */ }; static PyObject * EVP_repr(PyObject *self) { char buf[100]; PyOS_snprintf(buf, sizeof(buf), "<%s HASH object @ %p>", PyString_AsString(((EVPobject *)self)->name), self); return PyString_FromString(buf); } #if HASH_OBJ_CONSTRUCTOR static int EVP_tp_init(EVPobject *self, PyObject *args, PyObject *kwds) { static char *kwlist[] = {"name", "string", NULL}; PyObject *name_obj = NULL; char *nameStr; unsigned char *cp = NULL; Py_ssize_t len = 0; const EVP_MD *digest; if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|s#:HASH", kwlist, &name_obj, &cp, &len)) { return -1; } if (!PyArg_Parse(name_obj, "s", &nameStr)) { PyErr_SetString(PyExc_TypeError, "name must be a string"); return -1; } digest = EVP_get_digestbyname(nameStr); if (!digest) { PyErr_SetString(PyExc_ValueError, "unknown hash function"); return -1; } EVP_DigestInit(&self->ctx, digest); self->name = name_obj; Py_INCREF(self->name); if (cp && len) EVP_DigestUpdate(&self->ctx, cp, Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int)); return 0; } #endif PyDoc_STRVAR(hashtype_doc, "A hash represents the object used to calculate a checksum of a\n\ string of information.\n\ \n\ Methods:\n\ \n\ update() -- updates the current digest with an additional string\n\ digest() -- return the current digest value\n\ hexdigest() -- return the current digest as a string of hexadecimal digits\n\ copy() -- return a copy of the current hash object\n\ \n\ Attributes:\n\ \n\ name -- the hash algorithm being used by this object\n\ digest_size -- number of bytes in this hashes output\n"); static PyTypeObject EVPtype = { PyObject_HEAD_INIT(NULL) 0, /*ob_size*/ "_hashlib.HASH", /*tp_name*/ sizeof(EVPobject), /*tp_basicsize*/ 0, /*tp_itemsize*/ /* methods */ EVP_dealloc, /*tp_dealloc*/ 0, /*tp_print*/ 0, /*tp_getattr*/ 0, /*tp_setattr*/ 0, /*tp_compare*/ EVP_repr, /*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 | Py_TPFLAGS_BASETYPE, /*tp_flags*/ hashtype_doc, /*tp_doc*/ 0, /*tp_traverse*/ 0, /*tp_clear*/ 0, /*tp_richcompare*/ 0, /*tp_weaklistoffset*/ 0, /*tp_iter*/ 0, /*tp_iternext*/ EVP_methods, /* tp_methods */ EVP_members, /* tp_members */ EVP_getseters, /* tp_getset */ #if 1 0, /* tp_base */ 0, /* tp_dict */ 0, /* tp_descr_get */ 0, /* tp_descr_set */ 0, /* tp_dictoffset */ #endif #if HASH_OBJ_CONSTRUCTOR (initproc)EVP_tp_init, /* tp_init */ #endif }; static PyObject * EVPnew(PyObject *name_obj, const EVP_MD *digest, const EVP_MD_CTX *initial_ctx, const unsigned char *cp, unsigned int len) { EVPobject *self; if (!digest && !initial_ctx) { PyErr_SetString(PyExc_ValueError, "unsupported hash type"); return NULL; } if ((self = newEVPobject(name_obj)) == NULL) return NULL; if (initial_ctx) { EVP_MD_CTX_copy(&self->ctx, initial_ctx); } else { EVP_DigestInit(&self->ctx, digest); } if (cp && len) EVP_DigestUpdate(&self->ctx, cp, len); return (PyObject *)self; } /* The module-level function: new() */ PyDoc_STRVAR(EVP_new__doc__, "Return a new hash object using the named algorithm.\n\ An optional string argument may be provided and will be\n\ automatically hashed.\n\ \n\ The MD5 and SHA1 algorithms are always supported.\n"); static PyObject * EVP_new(PyObject *self, PyObject *args, PyObject *kwdict) { static char *kwlist[] = {"name", "string", NULL}; PyObject *name_obj = NULL; char *name; const EVP_MD *digest; unsigned char *cp = NULL; Py_ssize_t len = 0; if (!PyArg_ParseTupleAndKeywords(args, kwdict, "O|s#:new", kwlist, &name_obj, &cp, &len)) { return NULL; } if (!PyArg_Parse(name_obj, "s", &name)) { PyErr_SetString(PyExc_TypeError, "name must be a string"); return NULL; } digest = EVP_get_digestbyname(name); return EVPnew(name_obj, digest, NULL, cp, Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int)); } /* * This macro generates constructor function definitions for specific * hash algorithms. These constructors are much faster than calling * the generic one passing it a python string and are noticably * faster than calling a python new() wrapper. Thats important for * code that wants to make hashes of a bunch of small strings. */ #define GEN_CONSTRUCTOR(NAME) \ static PyObject * \ EVP_new_ ## NAME (PyObject *self, PyObject *args) \ { \ unsigned char *cp = NULL; \ Py_ssize_t len = 0; \ \ if (!PyArg_ParseTuple(args, "|s#:" #NAME , &cp, &len)) { \ return NULL; \ } \ \ return EVPnew( \ CONST_ ## NAME ## _name_obj, \ NULL, \ CONST_new_ ## NAME ## _ctx_p, \ cp, Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int)); \ } /* a PyMethodDef structure for the constructor */ #define CONSTRUCTOR_METH_DEF(NAME) \ {"openssl_" #NAME, (PyCFunction)EVP_new_ ## NAME, METH_VARARGS, \ PyDoc_STR("Returns a " #NAME \ " hash object; optionally initialized with a string") \ } /* used in the init function to setup a constructor */ #define INIT_CONSTRUCTOR_CONSTANTS(NAME) do { \ CONST_ ## NAME ## _name_obj = PyString_FromString(#NAME); \ if (EVP_get_digestbyname(#NAME)) { \ CONST_new_ ## NAME ## _ctx_p = &CONST_new_ ## NAME ## _ctx; \ EVP_DigestInit(CONST_new_ ## NAME ## _ctx_p, EVP_get_digestbyname(#NAME)); \ } \ } while (0); GEN_CONSTRUCTOR(md5) GEN_CONSTRUCTOR(sha1) GEN_CONSTRUCTOR(sha224) GEN_CONSTRUCTOR(sha256) GEN_CONSTRUCTOR(sha384) GEN_CONSTRUCTOR(sha512) /* List of functions exported by this module */ static struct PyMethodDef EVP_functions[] = { {"new", (PyCFunction)EVP_new, METH_VARARGS|METH_KEYWORDS, EVP_new__doc__}, CONSTRUCTOR_METH_DEF(md5), CONSTRUCTOR_METH_DEF(sha1), CONSTRUCTOR_METH_DEF(sha224), CONSTRUCTOR_METH_DEF(sha256), CONSTRUCTOR_METH_DEF(sha384), CONSTRUCTOR_METH_DEF(sha512), {NULL, NULL} /* Sentinel */ }; /* Initialize this module. */ PyMODINIT_FUNC init_hashlib(void) { PyObject *m; OpenSSL_add_all_digests(); /* TODO build EVP_functions openssl_* entries dynamically based * on what hashes are supported rather than listing many * but having some be unsupported. Only init appropriate * constants. */ EVPtype.ob_type = &PyType_Type; if (PyType_Ready(&EVPtype) < 0) return; m = Py_InitModule("_hashlib", EVP_functions); if (m == NULL) return; #if HASH_OBJ_CONSTRUCTOR Py_INCREF(&EVPtype); PyModule_AddObject(m, "HASH", (PyObject *)&EVPtype); #endif /* these constants are used by the convenience constructors */ INIT_CONSTRUCTOR_CONSTANTS(md5); INIT_CONSTRUCTOR_CONSTANTS(sha1); INIT_CONSTRUCTOR_CONSTANTS(sha224); INIT_CONSTRUCTOR_CONSTANTS(sha256); INIT_CONSTRUCTOR_CONSTANTS(sha384); INIT_CONSTRUCTOR_CONSTANTS(sha512); }