add numerical recipes library

lib/nr/ansi/recipes/psdes.c

@@ -0,0 +1,22 @@
+
+#define NITER 4
+
+void psdes(unsigned long *lword, unsigned long *irword)
+{
+	unsigned long i,ia,ib,iswap,itmph=0,itmpl=0;
+	static unsigned long c1[NITER]={
+		0xbaa96887L, 0x1e17d32cL, 0x03bcdc3cL, 0x0f33d1b2L};
+	static unsigned long c2[NITER]={
+		0x4b0f3b58L, 0xe874f0c3L, 0x6955c5a6L, 0x55a7ca46L};
+
+	for (i=0;i<NITER;i++) {
+		ia=(iswap=(*irword)) ^ c1[i];
+		itmpl = ia & 0xffff;
+		itmph = ia >> 16;
+		ib=itmpl*itmpl+ ~(itmph*itmph);
+		*irword=(*lword) ^ (((ia = (ib >> 16) |
+			((ib & 0xffff) << 16)) ^ c2[i])+itmpl*itmph);
+		*lword=iswap;
+	}
+}
+#undef NITER