/* -*-c-*-
*
- * $Id: square-mktab.c,v 1.1 2000/07/27 18:10:27 mdw Exp $
+ * $Id: square-mktab.c,v 1.2 2000/08/04 18:03:19 mdw Exp $
*
* Build precomputed tables for the Square block cipher
*
/*----- Revision history --------------------------------------------------*
*
* $Log: square-mktab.c,v $
+ * Revision 1.2 2000/08/04 18:03:19 mdw
+ * Fix comment describing the field in which inversion is done.
+ *
* Revision 1.1 2000/07/27 18:10:27 mdw
* Build precomuted tables for Square.
*
* Build the S-box.
*
* This is built from inversion in the multiplicative group of
- * %$\gf{2^8}[x]/(p(x))$%, where %$p(x) = x^8 + x^4 + x^3 + x + 1$%, followed
- * by an affine transformation treating inputs as vectors over %$\gf{2}$%.
- * The result is a horrible function.
+ * %$\gf{2^8}[x]/(p(x))$%, where %$p(x) = x^8+x^7+x^6+x^5+x^4+x^2+1$%,
+ * followed by an affine transformation treating inputs as vectors over
+ * %$\gf{2}$%. The result is a horrible function.
*
* The inversion is done slightly sneakily, by building log and antilog
* tables. Let %$a$% be an element of the finite field. If the inverse of