bn.h revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* Copyright (c) 1999 by Sun Microsystems, Inc.
* All rights reserved.
*/
/*
* Cylink Corporation � 1998
*
* This software is licensed by Cylink to the Internet Software Consortium to
* promote implementation of royalty free public key cryptography within IETF
* standards. Cylink wishes to expressly thank the contributions of Dr.
* Martin Hellman, Whitfield Diffie, Ralph Merkle and Stanford University for
* their contributions to Internet Security. In accordance with the terms of
* this license, ISC is authorized to distribute and sublicense this software
* for the practice of IETF standards.
*
* The software includes BigNum, written by Colin Plumb and licensed by Philip
* R. Zimmermann for royalty free use and distribution with Cylink's
* software. Use of BigNum as a stand alone product or component is
* specifically prohibited.
*
* Disclaimer of All Warranties. THIS SOFTWARE IS BEING PROVIDED "AS IS",
* WITHOUT ANY EXPRESSED OR IMPLIED WARRANTY OF ANY KIND WHATSOEVER. IN
* PARTICULAR, WITHOUT LIMITATION ON THE GENERALITY OF THE FOREGOING, CYLINK
* MAKES NO REPRESENTATION OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*
* Cylink or its representatives shall not be liable for tort, indirect,
* special or consequential damages such as loss of profits or loss of
* goodwill from the use or inability to use the software for any purpose or
* for any reason whatsoever.
*
* EXPORT LAW: Export of the Foundations Suite may be subject to compliance
* with the rules and regulations promulgated from time to time by the Bureau
* of Export Administration, United States Department of Commerce, which
* restrict the export and re-export of certain products and technical data.
* If the export of the Foundations Suite is controlled under such rules and
* regulations, then the Foundations Suite shall not be exported or
* re-exported, directly or indirectly, (a) without all export or re-export
* licenses and governmental approvals required by any applicable laws, or (b)
* in violation of any applicable prohibition against the export or re-export
* of any part of the Foundations Suite. All export licenses for software
* containing the Foundations Suite are the sole responsibility of the licensee.
*/
/*
* bn.h - the interface to the bignum routines.
* All functions which return ints can potentially allocate memory
* and return -1 if they are unable to. All "const" arguments
* are unmodified.
*
* This is not particularly asymmetric, as some operations are of the
* form a = b @ c, while others do a @= b. In general, outputs may not
* point to the same struct BigNums as inputs, except as specified
* below. This relationship is referred to as "being the same as".
* This is not numerical equivalence.
*
* The "Q" operations take "unsigned" inputs. Higher values of the
* extra input may work on some implementations, but 65535 is the
* highest portable value. Just because UNSIGNED_MAX is larger than
* that, or you know that the word size of the library is larger than that,
* that, does *not* mean it's allowed.
*/
#ifndef BN_H
#define BN_H
#pragma ident "%Z%%M% %I% %E% SMI"
struct BigNum {
void *ptr;
unsigned size; /* Note: in (variable-sized) words */
unsigned allocated;
};
/* Functions */
/*
* You usually never have to call this function explicitly, as
* bnBegin() takes care of it. If the program jumps to address 0,
* this function has bot been called.
*/
void bnInit(void);
/*
* This initializes an empty struct BigNum to a zero value.
* Do not use this on a BigNum which has had a value stored in it!
*/
/* Swap two BigNums. Cheap. */
/* Reset an initialized bigNum to empty, pending deallocation. */
/*
* If you know you'll need space in the number soon, you can use this function
* to ensure that there is room for at least "bits" bits. Optional.
* Returns <0 on out of memory, but the value is unaffected.
*/
/* Hopefully obvious. dest = src. dest may be the same as src. */
/*
* Mostly done automatically, but this removes leading zero words from
* the internal representation of the BigNum. Use is unclear.
*/
/*
* Move bytes between the given buffer and the given BigNum encoded in
* base 256. I.e. after either of these, the buffer will be equal to
* (bn / 256^lsbyte) % 256^len. The difference is which is altered to
* match the other!
*/
/* The same, but the buffer is little-endian. */
/* Return the least-significant bits (at least 16) of the BigNum */
/*
* Return the number of significant bits in the BigNum.
* 0 or 1+floor(log2(src))
*/
/*
* dest += src. dest and src may be the same. Guaranteed not to
* allocate memory unnecessarily, so if you're sure bnBits(dest)
* won't change, you don't need to check the return value.
*/
/*
* dest -= src. dest and src may be the same, but bnSetQ(dest, 0) is faster.
* if dest < src, returns +1 and sets dest = src-dest.
*/
/* Return sign (-1, 0, +1) of a-b. a <=> b --> bnCmpQ(a, b) <=> 0 */
/* dest = src, where 0 <= src < 2^16. */
/* dest += src, where 0 <= src < 2^16 */
/* dest -= src, where 0 <= src < 2^16 */
/* Return sign (-1, 0, +1) of a-b. a <=> b --> bnCmp(a, b) <=> 0 */
/* dest = src^2. dest may be the same as src, but it costs time. */
/* dest = a * b. dest may be the same as a or b, but it costs time. */
struct BigNum const *b);
/* dest = a * b, where 0 <= b < 2^16. dest and a may be the same. */
/*
* q = n/d, r = n%d. r may be the same as n, but not d,
* and q may not be the same as n or d.
* re-entrancy issue: this temporarily modifies d, but restores
* it for return.
*/
/*
* dest = src % d. dest and src may be the same, but not dest and d.
* re-entrancy issue: this temporarily modifies d, but restores
* it for return.
*/
struct BigNum const *d);
/* return src % d, where 0 <= d < 2^16. */
/* n = n^exp, modulo "mod" "mod" *must* be odd */
/*
* dest = n1^e1 * n2^e2, modulo "mod". "mod" *must* be odd.
* dest may be the same as n1 or n2.
*/
/* n = 2^exp, modulo "mod" "mod" *must* be odd */
/* dest = gcd(a, b). The inputs may overlap arbitrarily. */
struct BigNum const *b);
/* dest = src^-1, modulo "mod". dest may be the same as src. */
/* Shift dest left "amt" places */
/* Shift dest right "amt" places, discarding low-order bits */
/* For the largest 2^k that divides n, divide n by it and return k. */
#endif/* !BN_H */