FROM: python2.3-2.3.3/Modules/shamodule.c
/* SHA module */ /* This module provides an interface to NIST's Secure Hash Algorithm */ /* See below for information about the original code this module was based upon. Additional work performed by: Andrew Kuchling ([email protected]) Greg Stein ([email protected]) */ /* SHA objects */ #include "Python.h" /* Endianness testing and definitions */ #define TestEndianness(variable) {int i=1; variable=PCT_BIG_ENDIAN;\ if (*((char*)&i)==1) variable=PCT_LITTLE_ENDIAN;} #define PCT_LITTLE_ENDIAN 1 #define PCT_BIG_ENDIAN 0 /* Some useful types */ typedef unsigned char SHA_BYTE; #if SIZEOF_INT == 4 typedef unsigned int SHA_INT32; /* 32-bit integer */ #else /* not defined. compilation will die. */ #endif /* The SHA block size and message digest sizes, in bytes */ #define SHA_BLOCKSIZE 64 #define SHA_DIGESTSIZE 20 /* The structure for storing SHS info */ typedef struct { PyObject_HEAD SHA_INT32 digest[5]; /* Message digest */ SHA_INT32 count_lo, count_hi; /* 64-bit bit count */ SHA_BYTE data[SHA_BLOCKSIZE]; /* SHA data buffer */ int Endianness; int local; /* unprocessed amount in data */ } SHAobject; /* When run on a little-endian CPU we need to perform byte reversal on an array of longwords. */ static void longReverse(SHA_INT32 *buffer, int byteCount, int Endianness) { SHA_INT32 value; if ( Endianness == PCT_BIG_ENDIAN ) return; byteCount /= sizeof(*buffer); while (byteCount--) { value = *buffer; value = ( ( value & 0xFF00FF00L ) >> 8 ) | \ ( ( value & 0x00FF00FFL ) << 8 ); *buffer++ = ( value << 16 ) | ( value >> 16 ); } } static void SHAcopy(SHAobject *src, SHAobject *dest) { dest->Endianness = src->Endianness; dest->local = src->local; dest->count_lo = src->count_lo; dest->count_hi = src->count_hi; memcpy(dest->digest, src->digest, sizeof(src->digest)); memcpy(dest->data, src->data, sizeof(src->data)); } /* ------------------------------------------------------------------------ * * This code for the SHA 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. * */ /* NIST Secure Hash Algorithm */ /* heavily modified by Uwe Hollerbach <[email protected] edu> */ /* from Peter C. Gutmann's implementation as found in */ /* Applied Cryptography by Bruce Schneier */ /* Further modifications to include the "UNRAVEL" stuff, below */ /* This code is in the public domain */ /* UNRAVEL should be fastest & biggest */ /* UNROLL_LOOPS should be just as big, but slightly slower */ /* both undefined should be smallest and slowest */ #define UNRAVEL /* #define UNROLL_LOOPS */ /* The SHA f()-functions. The f1 and f3 functions can be optimized to save one boolean operation each - thanks to Rich Schroeppel, [email protected] for discovering this */ /*#define f1(x,y,z) ((x & y) | (~x & z)) // Rounds 0-19 */ #define f1(x,y,z) (z ^ (x & (y ^ z))) /* Rounds 0-19 */ #define f2(x,y,z) (x ^ y ^ z) /* Rounds 20-39 */ /*#define f3(x,y,z) ((x & y) | (x & z) | (y & z)) // Rounds 40-59 */ #define f3(x,y,z) ((x & y) | (z & (x | y))) /* Rounds 40-59 */ #define f4(x,y,z) (x ^ y ^ z) /* Rounds 60-79 */ /* SHA constants */ #define CONST1 0x5a827999L /* Rounds 0-19 */ #define CONST2 0x6ed9eba1L /* Rounds 20-39 */ #define CONST3 0x8f1bbcdcL /* Rounds 40-59 */ #define CONST4 0xca62c1d6L /* Rounds 60-79 */ /* 32-bit rotate */ #define R32(x,n) ((x << n) | (x >> (32 - n))) /* the generic case, for when the overall rotation is not unraveled */ #define FG(n) \ T = R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; \ E = D; D = C; C = R32(B,30); B = A; A = T /* specific cases, for when the overall rotation is unraveled */ #define FA(n) \ T = R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; B = R32(B,30) #define FB(n) \ E = R32(T,5) + f##n(A,B,C) + D + *WP++ + CONST##n; A = R32(A,30) #define FC(n) \ D = R32(E,5) + f##n(T,A,B) + C + *WP++ + CONST##n; T = R32(T,30) #define FD(n) \ C = R32(D,5) + f##n(E,T,A) + B + *WP++ + CONST##n; E = R32(E,30) #define FE(n) \ B = R32(C,5) + f##n(D,E,T) + A + *WP++ + CONST##n; D = R32(D,30) #define FT(n) \ A = R32(B,5) + f##n(C,D,E) + T + *WP++ + CONST##n; C = R32(C,30) /* do SHA transformation */ static void sha_transform(SHAobject *sha_info) { int i; SHA_INT32 T, A, B, C, D, E, W[80], *WP; memcpy(W, sha_info->data, sizeof(sha_info->data)); longReverse(W, (int)sizeof(sha_info->data), sha_info->Endianness); for (i = 16; i < 80; ++i) { W[i] = W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16]; /* extra rotation fix */ W[i] = R32(W[i], 1); } A = sha_info->digest[0]; B = sha_info->digest[1]; C = sha_info->digest[2]; D = sha_info->digest[3]; E = sha_info->digest[4]; WP = W; #ifdef UNRAVEL FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); sha_info->digest[0] += E; sha_info->digest[1] += T; sha_info->digest[2] += A; sha_info->digest[3] += B; sha_info->digest[4] += C; #else /* !UNRAVEL */ #ifdef UNROLL_LOOPS FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); #else /* !UNROLL_LOOPS */ for (i = 0; i < 20; ++i) { FG(1); } for (i = 20; i < 40; ++i) { FG(2); } for (i = 40; i < 60; ++i) { FG(3); } for (i = 60; i < 80; ++i) { FG(4); } #endif /* !UNROLL_LOOPS */ sha_info->digest[0] += A; sha_info->digest[1] += B; sha_info->digest[2] += C; sha_info->digest[3] += D; sha_info->digest[4] += E; #endif /* !UNRAVEL */ } /* initialize the SHA digest */ static void sha_init(SHAobject *sha_info) { TestEndianness(sha_info->Endianness) sha_info->digest[0] = 0x67452301L; sha_info->digest[1] = 0xefcdab89L; sha_info->digest[2] = 0x98badcfeL; sha_info->digest[3] = 0x10325476L; sha_info->digest[4] = 0xc3d2e1f0L; sha_info->count_lo = 0L; sha_info->count_hi = 0L; sha_info->local = 0; } /* update the SHA digest */ static void sha_update(SHAobject *sha_info, SHA_BYTE *buffer, int count) { int i; SHA_INT32 clo; clo = sha_info->count_lo + ((SHA_INT32) count << 3); if (clo < sha_info->count_lo) { ++sha_info->count_hi; } sha_info->count_lo = clo; sha_info->count_hi += (SHA_INT32) count >> 29; if (sha_info->local) { i = SHA_BLOCKSIZE - sha_info->local; if (i > count) { i = count; } memcpy(((SHA_BYTE *) sha_info->data) + sha_info->local, buffer, i); count -= i; buffer += i; sha_info->local += i; if (sha_info->local == SHA_BLOCKSIZE) { sha_transform(sha_info); } else { return; } } while (count >= SHA_BLOCKSIZE) { memcpy(sha_info->data, buffer, SHA_BLOCKSIZE); buffer += SHA_BLOCKSIZE; count -= SHA_BLOCKSIZE; sha_transform(sha_info); } memcpy(sha_info->data, buffer, count); sha_info->local = count; } /* finish computing the SHA digest */ static void sha_final(unsigned char digest[20], SHAobject *sha_info) { int count; SHA_INT32 lo_bit_count, hi_bit_count; lo_bit_count = sha_info->count_lo; hi_bit_count = sha_info->count_hi; count = (int) ((lo_bit_count >> 3) & 0x3f); ((SHA_BYTE *) sha_info->data)[count++] = 0x80; if (count > SHA_BLOCKSIZE - 8) { memset(((SHA_BYTE *) sha_info->data) + count, 0, SHA_BLOCKSIZE - count); sha_transform(sha_info); memset((SHA_BYTE *) sha_info->data, 0, SHA_BLOCKSIZE - 8); } else { memset(((SHA_BYTE *) sha_info->data) + count, 0, SHA_BLOCKSIZE - 8 - count); } /* GJS: note that we add the hi/lo in big-endian. sha_transform will swap these values into host-order. */ sha_info->data[56] = (hi_bit_count >> 24) & 0xff; sha_info->data[57] = (hi_bit_count >> 16) & 0xff; sha_info->data[58] = (hi_bit_count >> 8) & 0xff; sha_info->data[59] = (hi_bit_count >> 0) & 0xff; sha_info->data[60] = (lo_bit_count >> 24) & 0xff; sha_info->data[61] = (lo_bit_count >> 16) & 0xff; sha_info->data[62] = (lo_bit_count >> 8) & 0xff; sha_info->data[63] = (lo_bit_count >> 0) & 0xff; sha_transform(sha_info); digest[ 0] = (unsigned char) ((sha_info->digest[0] >> 24) & 0xff); digest[ 1] = (unsigned char) ((sha_info->digest[0] >> 16) & 0xff); digest[ 2] = (unsigned char) ((sha_info->digest[0] >> 8) & 0xff); digest[ 3] = (unsigned char) ((sha_info->digest[0] ) & 0xff); digest[ 4] = (unsigned char) ((sha_info->digest[1] >> 24) & 0xff); digest[ 5] = (unsigned char) ((sha_info->digest[1] >> 16) & 0xff); digest[ 6] = (unsigned char) ((sha_info->digest[1] >> 8) & 0xff); digest[ 7] = (unsigned char) ((sha_info->digest[1] ) & 0xff); digest[ 8] = (unsigned char) ((sha_info->digest[2] >> 24) & 0xff); digest[ 9] = (unsigned char) ((sha_info->digest[2] >> 16) & 0xff); digest[10] = (unsigned char) ((sha_info->digest[2] >> 8) & 0xff); digest[11] = (unsigned char) ((sha_info->digest[2] ) & 0xff); digest[12] = (unsigned char) ((sha_info->digest[3] >> 24) & 0xff); digest[13] = (unsigned char) ((sha_info->digest[3] >> 16) & 0xff); digest[14] = (unsigned char) ((sha_info->digest[3] >> 8) & 0xff); digest[15] = (unsigned char) ((sha_info->digest[3] ) & 0xff); digest[16] = (unsigned char) ((sha_info->digest[4] >> 24) & 0xff); digest[17] = (unsigned char) ((sha_info->digest[4] >> 16) & 0xff); digest[18] = (unsigned char) ((sha_info->digest[4] >> 8) & 0xff); digest[19] = (unsigned char) ((sha_info->digest[4] ) & 0xff); } /* * End of copied SHA code. * * ------------------------------------------------------------------------ */ static PyTypeObject SHAtype; static SHAobject * newSHAobject(void) { return (SHAobject *)PyObject_New(SHAobject, &SHAtype); } /* Internal methods for a hashing object */ static void SHA_dealloc(PyObject *ptr) { PyObject_Del(ptr); } /* External methods for a hashing object */ PyDoc_STRVAR(SHA_copy__doc__, "Return a copy of the hashing object."); static PyObject * SHA_copy(SHAobject *self, PyObject *args) { SHAobject *newobj; if (!PyArg_ParseTuple(args, ":copy")) { return NULL; } if ( (newobj = newSHAobject())==NULL) return NULL; SHAcopy(self, newobj); return (PyObject *)newobj; } PyDoc_STRVAR(SHA_digest__doc__, "Return the digest value as a string of binary data."); static PyObject * SHA_digest(SHAobject *self, PyObject *args) { unsigned char digest[SHA_DIGESTSIZE]; SHAobject temp; if (!PyArg_ParseTuple(args, ":digest")) return NULL; SHAcopy(self, &temp); sha_final(digest, &temp); return PyString_FromStringAndSize((const char *)digest, sizeof(digest)); } PyDoc_STRVAR(SHA_hexdigest__doc__, "Return the digest value as a string of hexadecimal digits."); static PyObject * SHA_hexdigest(SHAobject *self, PyObject *args) { unsigned char digest[SHA_DIGESTSIZE]; SHAobject temp; PyObject *retval; char *hex_digest; int i, j; if (!PyArg_ParseTuple(args, ":hexdigest")) return NULL; /* Get the raw (binary) digest value */ SHAcopy(self, &temp); sha_final(digest, &temp); /* Create a new string */ retval = PyString_FromStringAndSize(NULL, sizeof(digest) * 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<sizeof(digest); 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(SHA_update__doc__, "Update this hashing object's state with the provided string."); static PyObject * SHA_update(SHAobject *self, PyObject *args) { unsigned char *cp; int len; if (!PyArg_ParseTuple(args, "s#:update", &cp, &len)) return NULL; sha_update(self, cp, len); Py_INCREF(Py_None); return Py_None; } static PyMethodDef SHA_methods[] = { {"copy", (PyCFunction)SHA_copy, METH_VARARGS, SHA_copy__doc__}, {"digest", (PyCFunction)SHA_digest, METH_VARARGS, SHA_digest__doc__}, {"hexdigest", (PyCFunction)SHA_hexdigest, METH_VARARGS, SHA_hexdigest__doc__}, {"update", (PyCFunction)SHA_update, METH_VARARGS, SHA_update__doc__}, {NULL, NULL} /* sentinel */ }; static PyObject * SHA_getattr(PyObject *self, char *name) { if (strcmp(name, "blocksize")==0) return PyInt_FromLong(1); if (strcmp(name, "digest_size")==0 || strcmp(name, "digestsize")==0) return PyInt_FromLong(20); return Py_FindMethod(SHA_methods, self, name); } static PyTypeObject SHAtype = { PyObject_HEAD_INIT(NULL) 0, /*ob_size*/ "sha.SHA", /*tp_name*/ sizeof(SHAobject), /*tp_size*/ 0, /*tp_itemsize*/ /* methods */ SHA_dealloc, /*tp_dealloc*/ 0, /*tp_print*/ SHA_getattr, /*tp_getattr*/ }; /* The single module-level function: new() */ PyDoc_STRVAR(SHA_new__doc__, "Return a new SHA hashing object. An optional string argument\n\ may be provided; if present, this string will be automatically\n\ hashed."); static PyObject * SHA_new(PyObject *self, PyObject *args, PyObject *kwdict) { static char *kwlist[] = {"string", NULL}; SHAobject *new; unsigned char *cp = NULL; int len; if (!PyArg_ParseTupleAndKeywords(args, kwdict, "|s#:new", kwlist, &cp, &len)) { return NULL; } if ((new = newSHAobject()) == NULL) return NULL; sha_init(new); if (PyErr_Occurred()) { Py_DECREF(new); return NULL; } if (cp) sha_update(new, cp, len); return (PyObject *)new; } /* List of functions exported by this module */ static struct PyMethodDef SHA_functions[] = { {"new", (PyCFunction)SHA_new, METH_VARARGS|METH_KEYWORDS, SHA_new__doc__}, {"sha", (PyCFunction)SHA_new, METH_VARARGS|METH_KEYWORDS, SHA_new__doc__}, {NULL, NULL} /* Sentinel */ }; /* Initialize this module. */ #define insint(n,v) { PyModule_AddIntConstant(m,n,v); } PyMODINIT_FUNC initsha(void) { PyObject *m; SHAtype.ob_type = &PyType_Type; m = Py_InitModule("sha", SHA_functions); /* Add some symbolic constants to the module */ insint("blocksize", 1); /* For future use, in case some hash functions require an integral number of blocks */ insint("digestsize", 20); insint("digest_size", 20); }