NetBSD/lib/libcrypto/man/DH_set_method.3
2000-10-04 06:46:13 +00:00

311 lines
7.2 KiB
Groff

.rn '' }`
'''
'''
.de Sh
.br
.if t .Sp
.ne 5
.PP
\fB\\$1\fR
.PP
..
.de Sp
.if t .sp .5v
.if n .sp
..
.de Ip
.br
.ie \\n(.$>=3 .ne \\$3
.el .ne 3
.IP "\\$1" \\$2
..
.de Vb
.ft CW
.nf
.ne \\$1
..
.de Ve
.ft R
.fi
..
'''
'''
''' Set up \*(-- to give an unbreakable dash;
''' string Tr holds user defined translation string.
''' Bell System Logo is used as a dummy character.
'''
.tr \(*W-|\(bv\*(Tr
.ie n \{\
.ds -- \(*W-
.ds PI pi
.if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
.if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
.ds L" ""
.ds R" ""
''' \*(M", \*(S", \*(N" and \*(T" are the equivalent of
''' \*(L" and \*(R", except that they are used on ".xx" lines,
''' such as .IP and .SH, which do another additional levels of
''' double-quote interpretation
.ds M" """
.ds S" """
.ds N" """""
.ds T" """""
.ds L' '
.ds R' '
.ds M' '
.ds S' '
.ds N' '
.ds T' '
'br\}
.el\{\
.ds -- \(em\|
.tr \*(Tr
.ds L" ``
.ds R" ''
.ds M" ``
.ds S" ''
.ds N" ``
.ds T" ''
.ds L' `
.ds R' '
.ds M' `
.ds S' '
.ds N' `
.ds T' '
.ds PI \(*p
'br\}
.\" If the F register is turned on, we'll generate
.\" index entries out stderr for the following things:
.\" TH Title
.\" SH Header
.\" Sh Subsection
.\" Ip Item
.\" X<> Xref (embedded
.\" Of course, you have to process the output yourself
.\" in some meaninful fashion.
.if \nF \{
.de IX
.tm Index:\\$1\t\\n%\t"\\$2"
..
.nr % 0
.rr F
.\}
.TH DH_set_method 3 "0.9.5a" "22/Jul/100" "OpenSSL"
.UC
.if n .hy 0
.if n .na
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.de CQ \" put $1 in typewriter font
.ft CW
'if n "\c
'if t \\&\\$1\c
'if n \\&\\$1\c
'if n \&"
\\&\\$2 \\$3 \\$4 \\$5 \\$6 \\$7
'.ft R
..
.\" @(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2
. \" AM - accent mark definitions
.bd B 3
. \" fudge factors for nroff and troff
.if n \{\
. ds #H 0
. ds #V .8m
. ds #F .3m
. ds #[ \f1
. ds #] \fP
.\}
.if t \{\
. ds #H ((1u-(\\\\n(.fu%2u))*.13m)
. ds #V .6m
. ds #F 0
. ds #[ \&
. ds #] \&
.\}
. \" simple accents for nroff and troff
.if n \{\
. ds ' \&
. ds ` \&
. ds ^ \&
. ds , \&
. ds ~ ~
. ds ? ?
. ds ! !
. ds /
. ds q
.\}
.if t \{\
. ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
. ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
. ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
. ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
. ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
. ds ? \s-2c\h'-\w'c'u*7/10'\u\h'\*(#H'\zi\d\s+2\h'\w'c'u*8/10'
. ds ! \s-2\(or\s+2\h'-\w'\(or'u'\v'-.8m'.\v'.8m'
. ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
. ds q o\h'-\w'o'u*8/10'\s-4\v'.4m'\z\(*i\v'-.4m'\s+4\h'\w'o'u*8/10'
.\}
. \" troff and (daisy-wheel) nroff accents
.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
.ds v \\k:\h'-(\\n(.wu*9/10-\*(#H)'\v'-\*(#V'\*(#[\s-4v\s0\v'\*(#V'\h'|\\n:u'\*(#]
.ds _ \\k:\h'-(\\n(.wu*9/10-\*(#H+(\*(#F*2/3))'\v'-.4m'\z\(hy\v'.4m'\h'|\\n:u'
.ds . \\k:\h'-(\\n(.wu*8/10)'\v'\*(#V*4/10'\z.\v'-\*(#V*4/10'\h'|\\n:u'
.ds 3 \*(#[\v'.2m'\s-2\&3\s0\v'-.2m'\*(#]
.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
.ds ae a\h'-(\w'a'u*4/10)'e
.ds Ae A\h'-(\w'A'u*4/10)'E
.ds oe o\h'-(\w'o'u*4/10)'e
.ds Oe O\h'-(\w'O'u*4/10)'E
. \" corrections for vroff
.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
. \" for low resolution devices (crt and lpr)
.if \n(.H>23 .if \n(.V>19 \
\{\
. ds : e
. ds 8 ss
. ds v \h'-1'\o'\(aa\(ga'
. ds _ \h'-1'^
. ds . \h'-1'.
. ds 3 3
. ds o a
. ds d- d\h'-1'\(ga
. ds D- D\h'-1'\(hy
. ds th \o'bp'
. ds Th \o'LP'
. ds ae ae
. ds Ae AE
. ds oe oe
. ds Oe OE
.\}
.rm #[ #] #H #V #F C
.SH "NAME"
DH_set_default_method, DH_get_default_method, DH_set_method,
DH_new_method, DH_OpenSSL \- select DH method
.SH "LIBRARY"
libcrypto, -lcrypto
.SH "SYNOPSIS"
.PP
.Vb 1
\& #include <openssl/dh.h>
.Ve
.Vb 1
\& void DH_set_default_method(DH_METHOD *meth);
.Ve
.Vb 1
\& DH_METHOD *DH_get_default_method(void);
.Ve
.Vb 1
\& DH_METHOD *DH_set_method(DH *dh, DH_METHOD *meth);
.Ve
.Vb 1
\& DH *DH_new_method(DH_METHOD *meth);
.Ve
.Vb 1
\& DH_METHOD *DH_OpenSSL(void);
.Ve
.SH "DESCRIPTION"
A \fBDH_METHOD\fR specifies the functions that OpenSSL uses for Diffie-Hellman
operations. By modifying the method, alternative implementations
such as hardware accelerators may be used.
.PP
Initially, the default is to use the OpenSSL internal implementation.
\fIDH_OpenSSL()\fR returns a pointer to that method.
.PP
\fIDH_set_default_method()\fR makes \fBmeth\fR the default method for all \fBDH\fR
structures created later.
.PP
\fIDH_get_default_method()\fR returns a pointer to the current default
method.
.PP
\fIDH_set_method()\fR selects \fBmeth\fR for all operations using the structure \fBdh\fR.
.PP
\fIDH_get_method()\fR returns a pointer to the method currently selected
for \fBdh\fR.
.PP
\fIDH_new_method()\fR allocates and initializes a \fBDH\fR structure so that
\fBmethod\fR will be used for the DH operations. If \fBmethod\fR is \fBNULL\fR,
the default method is used.
.SH "THE DH_METHOD STRUCTURE"
.PP
.Vb 4
\& typedef struct dh_meth_st
\& {
\& /* name of the implementation */
\& const char *name;
.Ve
.Vb 2
\& /* generate private and public DH values for key agreement */
\& int (*generate_key)(DH *dh);
.Ve
.Vb 2
\& /* compute shared secret */
\& int (*compute_key)(unsigned char *key, BIGNUM *pub_key, DH *dh);
.Ve
.Vb 4
\& /* compute r = a ^ p mod m (May be NULL for some implementations) */
\& int (*bn_mod_exp)(DH *dh, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
\& const BIGNUM *m, BN_CTX *ctx,
\& BN_MONT_CTX *m_ctx);
.Ve
.Vb 2
\& /* called at DH_new */
\& int (*init)(DH *dh);
.Ve
.Vb 2
\& /* called at DH_free */
\& int (*finish)(DH *dh);
.Ve
.Vb 1
\& int flags;
.Ve
.Vb 1
\& char *app_data; /* ?? */
.Ve
.Vb 1
\& } DH_METHOD;
.Ve
.SH "RETURN VALUES"
\fIDH_OpenSSL()\fR, \fIDH_get_default_method()\fR and \fIDH_get_method()\fR return
pointers to the respective \fBDH_METHOD\fRs.
.PP
\fIDH_set_default_method()\fR returns no value.
.PP
\fIDH_set_method()\fR returns a pointer to the \fBDH_METHOD\fR previously
associated with \fBdh\fR.
.PP
\fIDH_new_method()\fR returns \fBNULL\fR and sets an error code that can be
obtained by the \fIERR_get_error(3)|ERR_get_error(3)\fR manpage if the allocation fails. Otherwise it
returns a pointer to the newly allocated structure.
.SH "SEE ALSO"
the \fIdh(3)|dh(3)\fR manpage, the \fIDH_new(3)|DH_new(3)\fR manpage
.SH "HISTORY"
\fIDH_set_default_method()\fR, \fIDH_get_default_method()\fR, \fIDH_set_method()\fR,
\fIDH_new_method()\fR and \fIDH_OpenSSL()\fR were added in OpenSSL 0.9.4.
.rn }` ''
.IX Title "DH_set_method 3"
.IX Name "DH_set_default_method, DH_get_default_method, DH_set_method,
DH_new_method, DH_OpenSSL - select DH method"
.IX Header "NAME"
.IX Header "SYNOPSIS"
.IX Header "DESCRIPTION"
.IX Header "THE DH_METHOD STRUCTURE"
.IX Header "RETURN VALUES"
.IX Header "SEE ALSO"
.IX Header "HISTORY"