BN_MONT_CTX_copy man page on UnixWare

Man page or keyword search:  
man Server   3616 pages
apropos Keyword Search (all sections)
Output format
UnixWare logo
[printable version]

BN_mod_mul_montgomery(3)	    OpenSSL	      BN_mod_mul_montgomery(3)

NAME
       BN_mod_mul_montgomery, BN_MONT_CTX_new, BN_MONT_CTX_init,
       BN_MONT_CTX_free, BN_MONT_CTX_set, BN_MONT_CTX_copy,
       BN_from_montgomery, BN_to_montgomery - Montgomery multiplication

SYNOPSIS
	#include <openssl/bn.h>

	BN_MONT_CTX *BN_MONT_CTX_new(void);
	void BN_MONT_CTX_init(BN_MONT_CTX *ctx);
	void BN_MONT_CTX_free(BN_MONT_CTX *mont);

	int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *m, BN_CTX *ctx);
	BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, BN_MONT_CTX *from);

	int BN_mod_mul_montgomery(BIGNUM *r, BIGNUM *a, BIGNUM *b,
		BN_MONT_CTX *mont, BN_CTX *ctx);

	int BN_from_montgomery(BIGNUM *r, BIGNUM *a, BN_MONT_CTX *mont,
		BN_CTX *ctx);

	int BN_to_montgomery(BIGNUM *r, BIGNUM *a, BN_MONT_CTX *mont,
		BN_CTX *ctx);

DESCRIPTION
       These functions implement Montgomery multiplication. They are used
       automatically when BN_mod_exp(3) is called with suitable input, but
       they may be useful when several operations are to be performed using
       the same modulus.

       BN_MONT_CTX_new() allocates and initializes a BN_MONT_CTX structure.
       BN_MONT_CTX_init() initializes an existing uninitialized BN_MONT_CTX.

       BN_MONT_CTX_set() sets up the mont structure from the modulus m by
       precomputing its inverse and a value R.

       BN_MONT_CTX_copy() copies the BN_MONT_CTX from to to.

       BN_MONT_CTX_free() frees the components of the BN_MONT_CTX, and, if it
       was created by BN_MONT_CTX_new(), also the structure itself.

       BN_mod_mul_montgomery() computes Mont(a,b):=a*b*R^-1 and places the
       result in r.

       BN_from_montgomery() performs the Montgomery reduction r = a*R^-1.

       BN_to_montgomery() computes Mont(a,R^2), i.e. a*R.  Note that a must be
       non-negative and smaller than the modulus.

       For all functions, ctx is a previously allocated BN_CTX used for
       temporary variables.

       The BN_MONT_CTX structure is defined as follows:

	typedef struct bn_mont_ctx_st
	       {
	       int ri;	       /* number of bits in R */
	       BIGNUM RR;      /* R^2 (used to convert to Montgomery form) */
	       BIGNUM N;       /* The modulus */
	       BIGNUM Ni;      /* R*(1/R mod N) - N*Ni = 1
				* (Ni is only stored for bignum algorithm) */
	       BN_ULONG n0;    /* least significant word of Ni */
	       int flags;
	       } BN_MONT_CTX;

       BN_to_montgomery() is a macro.

RETURN VALUES
       BN_MONT_CTX_new() returns the newly allocated BN_MONT_CTX, and NULL on
       error.

       BN_MONT_CTX_init() and BN_MONT_CTX_free() have no return values.

       For the other functions, 1 is returned for success, 0 on error.	The
       error codes can be obtained by ERR_get_error(3).

WARNING
       The inputs must be reduced modulo m, otherwise the result will be
       outside the expected range.

SEE ALSO
       bn(3), ERR_get_error(3), BN_add(3), BN_CTX_new(3)

HISTORY
       BN_MONT_CTX_new(), BN_MONT_CTX_free(), BN_MONT_CTX_set(),
       BN_mod_mul_montgomery(), BN_from_montgomery() and BN_to_montgomery()
       are available in all versions of SSLeay and OpenSSL.

       BN_MONT_CTX_init() and BN_MONT_CTX_copy() were added in SSLeay 0.9.1b.

3rd Berkeley Distribution	    0.9.7g	      BN_mod_mul_montgomery(3)
[top]
                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server UnixWare

List of man pages available for UnixWare

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net