Fixed gcry_mpi_set_bit and enhanced mpi_rshift.

Cleaned up andom-daemon initialization.

3 files changed, 246 insertions, 1 deletions

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 154bd5e2..af66e6ed 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,7 @@
+2006-08-03  Werner Koch  <wk@g10code.com>
+
+	* t-mpi-bit.c: New.
+
 2006-07-06  Werner Koch  <wk@g10code.com>
 
 	* benchmark.c (main): New option --use-random-daemon.  New command
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 945ce5d0..e4a922ac 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -18,7 +18,7 @@
 
 ## Process this file with automake to produce Makefile.in
 
-TESTS = prime register ac ac-schemes ac-data basic \
+TESTS = t-mpi-bit prime register ac ac-schemes ac-data basic \
         tsexp keygen pubkey benchmark pkbench hmac keygrip
 
 INCLUDES = -I$(top_srcdir)/src
diff --git a/tests/t-mpi-bit.c b/tests/t-mpi-bit.c
new file mode 100644
index 00000000..2465a8fd
--- /dev/null
+++ b/tests/t-mpi-bit.c
@@ -0,0 +1,241 @@
+/* t-mpi-bit.c  - Tests for bit level functions
+ * Copyright (C) 2006 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 
+ * MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <stdarg.h>
+
+#include "../src/gcrypt.h"
+
+#define PGM "t-mpi-bit"
+
+static const char *wherestr;
+static int verbose;
+static int error_count;
+
+#define xmalloc(a)    gcry_xmalloc ((a))
+#define xcalloc(a,b)  gcry_xcalloc ((a),(b))
+#define xfree(a)      gcry_free ((a))
+#define pass() do { ; } while (0)
+
+static void
+show (const char *format, ...)
+{
+  va_list arg_ptr;
+
+  if (!verbose)
+    return;
+  fprintf (stderr, "%s: ", PGM);
+  va_start (arg_ptr, format);
+  vfprintf (stderr, format, arg_ptr);
+  va_end (arg_ptr);
+}
+
+static void
+fail (const char *format, ...)
+{
+  va_list arg_ptr;
+
+  fflush (stdout);
+  fprintf (stderr, "%s: ", PGM);
+  if (wherestr)
+    fprintf (stderr, "%s: ", wherestr);
+  va_start (arg_ptr, format);
+  vfprintf (stderr, format, arg_ptr);
+  va_end (arg_ptr);
+  error_count++;
+}
+
+static void
+die (const char *format, ...)
+{
+  va_list arg_ptr;
+
+  fflush (stdout);
+  fprintf (stderr, "%s: ", PGM);
+  if (wherestr)
+    fprintf (stderr, "%s: ", wherestr);
+  va_start (arg_ptr, format);
+  vfprintf (stderr, format, arg_ptr);
+  va_end (arg_ptr);
+  exit (1);
+}
+
+/* Allocate a bit string consisting of '0' and '1' from the MPI
+   A. Return the LENGTH least significant bits. Caller needs to xfree
+   the result. */
+static char *
+mpi2bitstr (gcry_mpi_t a, size_t length)
+{
+  char *p, *buf;
+  
+  buf = p = xmalloc (length+1);
+  while (length--)
+    *p++ = gcry_mpi_test_bit (a, length) ? '1':'0';
+  *p = 0;
+
+  return buf;
+}
+
+/* Shift a bit string to the right. */
+static void
+rshiftbitstring (char *string, size_t n)
+{
+  size_t len = strlen (string);
+
+  if (n > len)
+    n = len;
+
+  memmove (string+n, string, len-n);
+  memset (string, '0', n);
+}
+
+
+/* This is to check a bug reported by bpgcrypt at itaparica.org on
+   2006-07-31 against libgcrypt 1.2.2.  */
+static void
+one_bit_only (int highbit)
+{
+  gcry_mpi_t a;
+  char *result;
+  int i;
+
+  wherestr = "one_bit_only";
+  show ("checking that set_%sbit does only set one bit\n", highbit?"high":"");
+
+  a = gcry_mpi_new (0);
+  gcry_mpi_randomize (a, 70, GCRY_WEAK_RANDOM);
+  gcry_mpi_set_ui (a, 0);
+
+  if (highbit)
+    gcry_mpi_set_highbit (a, 42);
+  else
+    gcry_mpi_set_bit (a, 42);
+  if (!gcry_mpi_test_bit (a, 42))
+    fail ("failed to set a bit\n");
+  gcry_mpi_clear_bit (a, 42);
+  if (gcry_mpi_test_bit (a, 42))
+    fail ("failed to clear a bit\n");
+  result = mpi2bitstr (a, 70);
+  assert (strlen (result) == 70);
+  show ("r=%s\n", result);
+  for (i=0; result[i]; i++)
+    if ( result[i] != '0' )
+      break;
+  if (result[i])
+    fail ("spurious bits detected\n");
+  xfree (result);
+  gcry_mpi_release (a);
+}
+
+/* Check that the shifting actually works for an amount larger than
+   the number of bits per limb. */
+static void
+test_rshift (int pass)
+{
+  gcry_mpi_t a, b;
+  char *result, *result2;
+  int i;
+
+  wherestr = "test_rshift";
+  show ("checking that rshift works as expected (pass %d)\n", pass);
+
+  a = gcry_mpi_new (0);
+  b = gcry_mpi_new (0);
+  gcry_mpi_randomize (a, 70, GCRY_WEAK_RANDOM);
+
+  for (i=0; i < 75; i++)
+    {
+      gcry_mpi_rshift (b, a, i);
+
+      result = mpi2bitstr (b, 72);
+      result2 = mpi2bitstr (a, 72);
+      rshiftbitstring (result2, i);
+      if (strcmp (result, result2))
+        {
+          show ("got =%s\n", result);
+          show ("want=%s\n", result2);
+          fail ("rshift by %d failed\n", i);
+        }
+      xfree (result);
+      xfree (result2);
+    }
+
+  /* Again. This time using in-place operation. */
+  gcry_mpi_randomize (a, 70, GCRY_WEAK_RANDOM);
+
+  for (i=0; i < 75; i++)
+    {
+      gcry_mpi_release (b);
+      b = gcry_mpi_copy (a);
+      gcry_mpi_rshift (b, b, i);
+
+      result = mpi2bitstr (b, 72);
+      result2 = mpi2bitstr (a, 72);
+      rshiftbitstring (result2, i);
+      if (strcmp (result, result2))
+        {
+          show ("got =%s\n", result);
+          show ("want=%s\n", result2);
+          fail ("in-place rshift by %d failed\n", i);
+        }
+      xfree (result2);
+      xfree (result);
+    }
+
+  gcry_mpi_release (b);
+  gcry_mpi_release (a);
+}
+
+
+int
+main (int argc, char **argv)
+{
+  int debug = 0;
+  int i;
+
+  if (argc > 1 && !strcmp (argv[1], "--verbose"))
+    verbose = 1;
+  else if (argc > 1 && !strcmp (argv[1], "--debug"))
+    verbose = debug = 1;
+
+  if (!gcry_check_version (GCRYPT_VERSION))
+    die ("version mismatch\n");
+
+  gcry_control (GCRYCTL_DISABLE_SECMEM, 0);
+  gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+  if (debug)
+    gcry_control (GCRYCTL_SET_DEBUG_FLAGS, 1u, 0);
+  gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0);
+
+  one_bit_only (0);
+  one_bit_only (1);
+  for (i=0; i < 5; i++)
+    test_rshift (i); /* Run several times due to random initializations. */
+  
+  show ("All tests completed. Errors: %d\n", error_count);
+  return error_count ? 1 : 0;
+}