From aa51dd58d333e22178574631e986e39f4ad58ee9 Mon Sep 17 00:00:00 2001
From: Unknown User d91-jda <d91-jda@nada.kth.se>
Date: Wed, 18 Oct 1995 23:25:41 +0000
Subject: [PATCH] Initial revision

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@158 ec53bebd-3082-4978-b11e-865c3cabbd6b
---
 lib/des/set_key.c | 178 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 178 insertions(+)
 create mode 100644 lib/des/set_key.c

diff --git a/lib/des/set_key.c b/lib/des/set_key.c
new file mode 100644
index 000000000..b7b9dd088
--- /dev/null
+++ b/lib/des/set_key.c
@@ -0,0 +1,178 @@
+/* set_key.c */
+/* Copyright (C) 1993 Eric Young - see README for more details */
+/* set_key.c v 1.4 eay 24/9/91
+ * 1.4 Speed up by 400% :-)
+ * 1.3 added register declarations.
+ * 1.2 unrolled make_key_sched a bit more
+ * 1.1 added norm_expand_bits
+ * 1.0 First working version
+ */
+#include "des_locl.h"
+#include "podd.h"
+#include "sk.h"
+
+static int check_parity(des_cblock (*key));
+
+int des_check_key=0;
+
+void des_set_odd_parity(des_cblock (*key))
+{
+  int i;
+
+  for (i=0; i<DES_KEY_SZ; i++)
+    (*key)[i]=odd_parity[(*key)[i]];
+}
+
+static int check_parity(des_cblock (*key))
+{
+  int i;
+
+  for (i=0; i<DES_KEY_SZ; i++)
+    {
+      if ((*key)[i] != odd_parity[(*key)[i]])
+	return(0);
+    }
+  return(1);
+}
+
+/* Weak and semi week keys as take from
+ * %A D.W. Davies
+ * %A W.L. Price
+ * %T Security for Computer Networks
+ * %I John Wiley & Sons
+ * %D 1984
+ * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference
+ * (and actual cblock values).
+ */
+#define NUM_WEAK_KEY	16
+static des_cblock weak_keys[NUM_WEAK_KEY]={
+  /* weak keys */
+  0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
+  0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,
+  0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,
+  0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,
+  /* semi-weak keys */
+  0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,
+  0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,
+  0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1,
+  0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E,
+  0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,
+  0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01,
+  0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE,
+  0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,
+  0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,
+  0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01,
+  0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE,
+  0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1};
+
+int des_is_weak_key(des_cblock (*key))
+{
+  int i;
+
+  for (i=0; i<NUM_WEAK_KEY; i++)
+    /* Added == 0 to comparision, I obviously don't run
+     * this section very often :-(, thanks to
+     * engineering@MorningStar.Com for the fix
+     * eay 93/06/29 */
+    if (memcmp(weak_keys[i],key,sizeof(key)) == 0) return(1);
+  return(0);
+}
+
+/* NOW DEFINED IN des_local.h
+ * See ecb_encrypt.c for a pseudo description of these macros. 
+ * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
+			       * 	(b)^=(t),\
+			       * 	(a)=((a)^((t)<<(n))))
+			       */
+
+#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
+			   (a)=(a)^(t)^(t>>(16-(n))))
+
+static char shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
+
+/* return 0 if key parity is odd (correct),
+ * return -1 if key parity error,
+ * return -2 if illegal weak key.
+ */
+int des_set_key(des_cblock (*key), struct des_ks_struct *schedule)
+{
+  register u_int32_t c,d,t,s;
+  register unsigned char *in;
+  register u_int32_t *k;
+  register int i;
+
+  if (des_check_key)
+    {
+      if (!check_parity(key))
+	return(-1);
+
+      if (des_is_weak_key(key))
+	return(-2);
+    }
+
+  k=(u_int32_t *)schedule;
+  in=(unsigned char *)key;
+
+  c2l(in,c);
+  c2l(in,d);
+
+  /* do PC1 in 60 simple operations */ 
+  /*	PERM_OP(d,c,t,4,0x0f0f0f0f);
+	HPERM_OP(c,t,-2, 0xcccc0000);
+	HPERM_OP(c,t,-1, 0xaaaa0000);
+	HPERM_OP(c,t, 8, 0x00ff0000);
+	HPERM_OP(c,t,-1, 0xaaaa0000);
+	HPERM_OP(d,t,-8, 0xff000000);
+	HPERM_OP(d,t, 8, 0x00ff0000);
+	HPERM_OP(d,t, 2, 0x33330000);
+	d=((d&0x00aa00aa)<<7)|((d&0x55005500)>>7)|(d&0xaa55aa55);
+	d=(d>>8)|((c&0xf0000000)>>4);
+	c&=0x0fffffff; */
+
+  /* I now do it in 47 simple operations :-)
+   * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
+   * for the inspiration. :-) */
+  PERM_OP (d,c,t,4,0x0f0f0f0f);
+  HPERM_OP(c,t,-2,0xcccc0000);
+  HPERM_OP(d,t,-2,0xcccc0000);
+  PERM_OP (d,c,t,1,0x55555555);
+  PERM_OP (c,d,t,8,0x00ff00ff);
+  PERM_OP (d,c,t,1,0x55555555);
+  d=	(((d&0x000000ff)<<16)| (d&0x0000ff00)     |
+	 ((d&0x00ff0000)>>16)|((c&0xf0000000)>>4));
+  c&=0x0fffffff;
+
+  for (i=0; i<ITERATIONS; i++)
+    {
+      if (shifts2[i])
+	{ c=((c>>2)|(c<<26)); d=((d>>2)|(d<<26)); }
+      else
+	{ c=((c>>1)|(c<<27)); d=((d>>1)|(d<<27)); }
+      c&=0x0fffffff;
+      d&=0x0fffffff;
+      /* could be a few less shifts but I am to lazy at this
+       * point in time to investigate */
+      s=	des_skb[0][ (c    )&0x3f                ]|
+	des_skb[1][((c>> 6)&0x03)|((c>> 7)&0x3c)]|
+	  des_skb[2][((c>>13)&0x0f)|((c>>14)&0x30)]|
+	    des_skb[3][((c>>20)&0x01)|((c>>21)&0x06) |
+		       ((c>>22)&0x38)];
+      t=	des_skb[4][ (d    )&0x3f                ]|
+	des_skb[5][((d>> 7)&0x03)|((d>> 8)&0x3c)]|
+	  des_skb[6][ (d>>15)&0x3f                ]|
+	    des_skb[7][((d>>21)&0x0f)|((d>>22)&0x30)];
+
+      /* table contained 0213 4657 */
+      *(k++)=((t<<16)|(s&0x0000ffff))&0xffffffff;
+      s=     ((s>>16)|(t&0xffff0000));
+		
+      s=(s<<4)|(s>>28);
+      *(k++)=s&0xffffffff;
+    }
+  return(0);
+}
+
+int des_key_sched(des_cblock *key, des_key_schedule schedule)
+{
+  return(des_set_key(key, (struct des_ks_struct *)schedule));
+}