X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/ba6e6b64033b1f9de49feccb5c9cd438354481f7..0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a:/symm/serpent-check.c?ds=sidebyside

diff --git a/symm/serpent-check.c b/symm/serpent-check.c
new file mode 100644
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+++ b/symm/serpent-check.c
@@ -0,0 +1,99 @@
+/* -*-c-*-
+ *
+ * Check the Serpent S-boxes
+ *
+ * (c) 2000 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb 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 Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <mLib/bits.h>
+
+#include "serpent-sbox.h"
+
+/*----- S-box tables ------------------------------------------------------*/
+
+static const octet s[8][16] = {
+  {  3,	 8, 15,	 1, 10,	 6,  5, 11, 14, 13,  4,	 2,  7,	 0,  9, 12 },
+  { 15, 12,  2,	 7,  9,	 0,  5, 10,  1, 11, 14,	 8,  6, 13,  3,	 4 },
+  {  8,	 6,  7,	 9,  3, 12, 10, 15, 13,	 1, 14,	 4,  0, 11,  5,	 2 },
+  {  0, 15, 11,	 8, 12,	 9,  6,	 3, 13,	 1,  2,	 4, 10,	 7,  5, 14 },
+  {  1, 15,  8,	 3, 12,	 0, 11,	 6,  2,	 5,  4, 10,  9, 14,  7, 13 },
+  { 15,	 5,  2, 11,  4, 10,  9, 12,  0,	 3, 14,	 8, 13,	 6,  7,	 1 },
+  {  7,	 2, 12,	 5,  8,	 4,  6, 11, 14,	 9,  1, 15, 13,	 3, 10,	 0 },
+  {  1, 13, 15,	 0, 14,	 8,  2, 11,  7,	 4, 12, 10,  9,	 3,  5,	 6 }
+};
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @check@ --- *
+ *
+ * Arguments:	@unsigned a, b, c, d@ = four bitslice output registers
+ *		@const octet *p@ = pointer to S-box
+ *
+ * Returns:	Zero if OK, nonzero on failure.
+ *
+ * Use:		Checks that an S-box output is correct.
+ */
+
+static int check(unsigned a, unsigned b, unsigned c, unsigned d,
+		 const octet *p)
+{
+  octet buf[16];
+  octet *q = buf;
+  unsigned i;
+
+  for (i = 0; i < 16; i++) {
+    *q++ = (a & 1) | ((b & 1) << 1) | ((c & 1) << 2) | ((d & 1) << 3);
+    a >>= 1; b >>= 1; c >>= 1; d >>= 1;
+  }
+  return (memcmp(buf, p, sizeof(buf)));
+}
+
+#define CHECK(i) do {							\
+  unsigned a = 0xaaaa, b = 0xcccc, c = 0xf0f0, d = 0xff00;		\
+  S##i(a, b, c, d);							\
+  if (check(a, b, c, d, s[i])) {					\
+    fprintf(stderr, "failure in S%i\n", i);				\
+    rc = EXIT_FAILURE;							\
+  }									\
+  IS##i(a, b, c, d);							\
+  if (a != 0xaaaa || b != 0xcccc || c != 0xf0f0 || d != 0xff00) {	\
+    fprintf(stderr, "failure in IS%i\n", i);				\
+    rc = EXIT_FAILURE;							\
+  }									\
+} while (0)
+
+int main(void)
+{
+  int rc = 0;
+  CHECK(0); CHECK(1); CHECK(2); CHECK(3);
+  CHECK(4); CHECK(5); CHECK(6); CHECK(7);
+  return (rc);
+}
+
+/*----- That's all, folks -------------------------------------------------*/