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LIBMP(3)		 BSD Library Functions Manual		      LIBMP(3)

     libmp -- traditional BSD multiple precision integer arithmetic library

     #include <mp.h>

     Function prototypes are given in the main body of the text.

     Applications using	this interface must be linked with -lmp	(this library)
     and -lcrypto (crypto(3)).

     This interface is obsolete	in favor of the	crypto(3) BIGNUM library.

     libmp is the traditional BSD multiple precision integer arithmetic	li-
     brary.  It	has a number of	problems, and is unsuitable for	use in any
     programs where reliability	is a concern.  It is provided here for compat-
     ibility only.

     These routines perform arithmetic on integers of arbitrary	precision
     stored using the defined type MINT.  Pointers to MINT are initialized us-
     ing mp_itom() or mp_xtom(), and must be recycled with mp_mfree() when
     they are no longer	needed.	 Routines which	store a	result in one of their
     arguments expect that the latter has also been initialized	prior to being
     passed to it.  The	following routines are defined and implemented:

     MINT *mp_itom(short n);

     MINT *mp_xtom(const char *s);

     char *mp_mtox(const MINT *mp);

     void mp_mfree(MINT	*mp);

	   mp_itom() returns an	MINT with the value of n.  mp_xtom() returns
	   an MINT with	the value of s,	which is treated to be in hexadecimal.
	   The return values from mp_itom() and	mp_xtom() must be released
	   with	mp_mfree() when	they are no longer needed.  mp_mtox() returns
	   a null-terminated hexadecimal string	having the value of mp;	its
	   return value	must be	released with free() (free(3)) when it is no
	   longer needed.

     void mp_madd(const	MINT *mp1, const MINT *mp2, MINT *rmp);

     void mp_msub(const	MINT *mp1, const MINT *mp2, MINT *rmp);

     void mp_mult(const	MINT *mp1, const MINT *mp2, MINT *rmp);

	   mp_madd(), mp_msub(), and mp_mult() store the sum, difference, or
	   product, respectively, of mp1 and mp2 in rmp.

     void mp_mdiv(const	MINT *nmp, const MINT *dmp, MINT *qmp, MINT *rmp);

     void mp_sdiv(const	MINT *nmp, short d, MINT *qmp, short *ro);

	   mp_mdiv() computes the quotient and remainder of nmp	and dmp	and
	   stores the result in	qmp and	rmp, respectively.  mp_sdiv() is simi-
	   lar to mp_mdiv() except the divisor (dmp or d) and remainder	(rmp
	   or ro) are ordinary integers.

     void mp_pow(const MINT *bmp, const	MINT *emp, const MINT *mmp, MINT

     void mp_rpow(const	MINT *bmp, short e, MINT *rmp);

	   mp_rpow() computes the result of bmp	raised to the empth power and
	   reduced modulo mmp; the result is stored in rmp.  mp_pow() computes
	   the result of bmp raised to the eth power and stores	the result in

     void mp_min(MINT *mp);

     void mp_mout(const	MINT *mp);

	   mp_min() reads a line from standard input, tries to interpret it as
	   a decimal number, and if successful,	stores the result in mp.
	   mp_mout() prints the	value, in decimal, of mp to standard output
	   (without a trailing newline).

     void mp_gcd(const MINT *mp1, const	MINT *mp2, MINT	*rmp);

	   mp_gcd() computes the greatest common divisor of mp1	and mp2	and
	   stores the result in	rmp.

     int mp_mcmp(const MINT *mp1, const	MINT *mp2);

	   mcmp	compares the values of mp1 and mp2 and returns 0 if the	two
	   values are equal, a value greater than 0 if mp1 is greater than
	   mp2,	and a value less than 0	if mp2 is greater than mp1.

     void mp_move(const	MINT *smp, MINT	*tmp);

	   mp_move() copies the	value of smp to	tmp (both values must be ini-

     void mp_msqrt(const MINT *nmp, MINT *xmp, MINT *rmp);

	   mp_msqrt() computes the square root and remainder of	nmp and	stores
	   them	in xmp and rmp,	respectively.

     This version of libmp is implemented in terms of the crypto(3) BIGNUM li-

     Running out of memory or illegal operations result	in error messages on
     standard error and	a call to abort(3).

     abort(3), bn(3), crypto(3), free(3), malloc(3), math(3)

     A libmp library appeared in 4.3BSD.  FreeBSD 2.2 shipped with a libmp im-
     plemented in terms	of libgmp.  This implementation	appeared in
     FreeBSD 5.0.

     Errors are	reported via output to standard	error and abnormal program
     termination instead of via	return values.	The application	cannot control
     this behavior.

     It	is not clear whether the string	returned by mp_mtox() may be written
     to	by the caller.	This implementation allows it, but others may not.
     Ideally, mp_mtox()	would take a pointer to	a buffer to fill in.

     It	is not clear whether using the same variable as	both source and	desti-
     nation in a single	invocation is permitted.  Some of the calls in this
     implementation allow this,	while others do	not.

BSD			       September 7, 1989			   BSD


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