Added Greg Stein and Andrew Kuchling's sha module.

Fix comments about zlib version and URL.

2 files changed, 610 insertions, 1 deletions

diff --git a/Modules/Setup.in b/Modules/Setup.in
index 43e175b..ca307bf 100644
--- a/Modules/Setup.in
+++ b/Modules/Setup.in
@@ -199,6 +199,11 @@ errno errnomodule.c	# posix (UNIX) errno values
 md5 md5module.c md5c.c
 
 
+# The sha module implements the SHA checksum algorithm.
+# (NIST's Secure Hash Algorithm.)
+sha shamodule.c
+
+
 # The mpz module interfaces to the GNU Multiple Precision library.
 # You need to ftp the GNU MP library.  
 # The GMP variable must point to the GMP source directory.
@@ -399,7 +404,7 @@ cPickle cPickle.c
 #fpetest fpetestmodule.c
 
 # Andrew Kuchling's zlib module.
-# This require zlib 1.0.4 (or later).  See http://quest.jpl.nasa.gov/zlib/
+# This require zlib 1.1.3 (or later).
 # See http://www.cdrom.com/pub/infozip/zlib/
 #zlib zlibmodule.c -I$(prefix)/include -L$(exec_prefix)/lib -lz
 
diff --git a/Modules/shamodule.c b/Modules/shamodule.c
new file mode 100644
index 0000000..06e58f0
--- /dev/null
+++ b/Modules/shamodule.c
@@ -0,0 +1,604 @@
+/***********************************************************
+Copyright 1999 by Stichting Mathematisch Centrum, Amsterdam,
+The Netherlands.
+
+                        All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the names of Stichting Mathematisch
+Centrum or CWI or Corporation for National Research Initiatives or
+CNRI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior
+permission.
+
+While CWI is the initial source for this software, a modified version
+is made available by the Corporation for National Research Initiatives
+(CNRI) at the Internet address ftp://ftp.python.org.
+
+STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
+CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
+DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+PERFORMANCE OF THIS SOFTWARE.
+
+******************************************************************/
+
+/* 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 (amk1@erols.com)
+   Greg Stein (gstein@lyra.org)
+*/
+
+/* 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(buffer, byteCount, Endianness)
+    SHA_INT32 *buffer; 
+    int byteCount, 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(src, dest)
+     SHAobject *src, *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 <uh@alumni.caltech 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,
+   rcs@cs.arizona.edu 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(sha_info)
+	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, 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(sha_info)
+    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(sha_info, buffer, count)
+    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(digest, sha_info)
+    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.
+ *
+ * ------------------------------------------------------------------------
+ */
+
+staticforward PyTypeObject SHAtype;
+
+
+static SHAobject *
+newSHAobject()
+{
+	return (SHAobject *)PyObject_NEW(SHAobject, &SHAtype);
+}
+
+/* Internal methods for a hashing object */
+
+static void
+SHA_dealloc(ptr)
+	PyObject *ptr;
+{
+	PyMem_DEL(ptr);
+}
+
+
+/* External methods for a hashing object */
+
+static char SHA_copy__doc__[] = 
+"Return a copy of the hashing object.";
+
+static PyObject *
+SHA_copy(self, args)
+	SHAobject *self;
+	PyObject *args;
+{
+	SHAobject *newobj;
+
+	if (!PyArg_NoArgs(args)) {
+		return NULL;
+	}
+
+	if ( (newobj = newSHAobject())==NULL)
+		return NULL;
+	
+	SHAcopy(self, newobj);
+	return (PyObject *)newobj;
+}
+
+static char SHA_digest__doc__[] = 
+"Return the digest value as a string of binary data.";
+
+static PyObject *
+SHA_digest(self, args)
+	SHAobject *self;
+	PyObject *args;
+{
+	unsigned char digest[SHA_DIGESTSIZE];
+	SHAobject temp;
+
+	if (!PyArg_NoArgs(args))
+		return NULL;
+
+	SHAcopy(self, &temp);
+	sha_final(digest, &temp);
+	return PyString_FromStringAndSize(digest, sizeof(digest));
+}
+
+static char SHA_hexdigest__doc__[] = 
+"Return the digest value as a string of hexadecimal digits.";
+
+static PyObject *
+SHA_hexdigest(self, args)
+	SHAobject *self;
+	PyObject *args;
+{
+	unsigned char digest[SHA_DIGESTSIZE];
+	SHAobject temp;
+	PyObject *retval;
+	char *hex_digest;
+	int i, j;
+
+	if (!PyArg_NoArgs(args))
+		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);
+	hex_digest = PyString_AsString(retval);
+
+	/* Make hex version of the digest */
+	for(i=j=0; i<sizeof(digest); i++)	
+	{
+		char c;
+		c = digest[i] / 16; c = (c>9) ? c+'a'-10 : c + '0';
+		hex_digest[j++] = c;
+		c = digest[i] % 16; c = (c>9) ? c+'a'-10 : c + '0';
+		hex_digest[j++] = c;
+	}
+
+	return retval;
+}
+
+static char SHA_update__doc__[] = 
+"Update this hashing object's state with the provided string.";
+
+static PyObject *
+SHA_update(self, args)
+	SHAobject *self;
+	PyObject *args;
+{
+	unsigned char *cp;
+	int len;
+
+	if (!PyArg_Parse(args, "s#", &cp, &len))
+		return NULL;
+
+	sha_update(self, cp, len);
+
+	Py_INCREF(Py_None);
+	return Py_None;
+}
+
+static PyMethodDef SHA_methods[] = {
+	{"copy",	(PyCFunction)SHA_copy, 0, SHA_copy__doc__},
+	{"digest",	(PyCFunction)SHA_digest, 0, SHA_digest__doc__},
+	{"hexdigest",	(PyCFunction)SHA_hexdigest, 0, SHA_hexdigest__doc__},
+	{"update",	(PyCFunction)SHA_update, 0, SHA_update__doc__},
+	{NULL,		NULL}		/* sentinel */
+};
+
+static PyObject *
+SHA_getattr(self, name)
+	SHAobject *self;
+	char *name;
+{
+	if (strcmp(name, "blocksize")==0)
+		return PyInt_FromLong(1);
+	if (strcmp(name, "digestsize")==0)
+		return PyInt_FromLong(20);
+	
+	return Py_FindMethod(SHA_methods, (PyObject *)self, name);
+}
+
+static PyTypeObject SHAtype = {
+	PyObject_HEAD_INIT(NULL)
+	0,			/*ob_size*/
+	"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() */
+
+static char SHA_new__doc__[] =
+ "Return a new SHA hashing object.  An optional string "
+ "argument may be provided; if present, this string will be "
+ " automatically hashed."; 
+
+static PyObject *
+SHA_new(self, args, kwdict)
+	PyObject *self;
+	PyObject *args;
+	PyObject *kwdict;
+{
+	static char *kwlist[] = {"string", NULL};
+	SHAobject *new;
+	unsigned char *cp = NULL;
+	int len;
+	
+	if ((new = newSHAobject()) == NULL)
+		return NULL;
+
+	if (!PyArg_ParseTupleAndKeywords(args, kwdict, "|s#", kwlist,
+					 &cp, &len)) {
+	        Py_DECREF(new);
+		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) { PyObject *o=PyInt_FromLong(v); \
+	if (o!=NULL) PyDict_SetItemString(d,n,o); \
+	Py_XDECREF(o); }
+
+void
+initsha()
+{
+	PyObject *d, *m;
+
+	SHAtype.ob_type = &PyType_Type;
+	m = Py_InitModule("sha", SHA_functions);
+
+	/* Add some symbolic constants to the module */
+	d = PyModule_GetDict(m);
+	insint("blocksize", 1);  /* For future use, in case some hash
+				    functions require an integral number of
+				    blocks */ 
+	insint("digestsize", 20);
+
+	/* Check for errors */
+	if (PyErr_Occurred())
+		Py_FatalError("can't initialize module SHA");
+}
+