05ea606a25
Fix some code examples, trailing whitespace Fix TBA sections in verify, remove others. Remove empty sections Use Mixed Case not ALL CAPS in head2 Enhance doc-nits script. Remove extra =cut line Reviewed-by: Richard Levitte <levitte@openssl.org>
180 lines
6.7 KiB
Text
180 lines
6.7 KiB
Text
=pod
|
|
|
|
=head1 NAME
|
|
|
|
RSA_set_default_method, RSA_get_default_method, RSA_set_method,
|
|
RSA_get_method, RSA_PKCS1_OpenSSL, RSA_null_method, RSA_flags,
|
|
RSA_new_method - select RSA method
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/rsa.h>
|
|
|
|
void RSA_set_default_method(const RSA_METHOD *meth);
|
|
|
|
RSA_METHOD *RSA_get_default_method(void);
|
|
|
|
int RSA_set_method(RSA *rsa, const RSA_METHOD *meth);
|
|
|
|
RSA_METHOD *RSA_get_method(const RSA *rsa);
|
|
|
|
RSA_METHOD *RSA_PKCS1_OpenSSL(void);
|
|
|
|
RSA_METHOD *RSA_null_method(void);
|
|
|
|
int RSA_flags(const RSA *rsa);
|
|
|
|
RSA *RSA_new_method(ENGINE *engine);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
An B<RSA_METHOD> specifies the functions that OpenSSL uses for RSA
|
|
operations. By modifying the method, alternative implementations such as
|
|
hardware accelerators may be used. IMPORTANT: See the NOTES section for
|
|
important information about how these RSA API functions are affected by the
|
|
use of B<ENGINE> API calls.
|
|
|
|
Initially, the default RSA_METHOD is the OpenSSL internal implementation,
|
|
as returned by RSA_PKCS1_OpenSSL().
|
|
|
|
RSA_set_default_method() makes B<meth> the default method for all RSA
|
|
structures created later. B<NB>: This is true only whilst no ENGINE has
|
|
been set as a default for RSA, so this function is no longer recommended.
|
|
|
|
RSA_get_default_method() returns a pointer to the current default
|
|
RSA_METHOD. However, the meaningfulness of this result is dependent on
|
|
whether the ENGINE API is being used, so this function is no longer
|
|
recommended.
|
|
|
|
RSA_set_method() selects B<meth> to perform all operations using the key
|
|
B<rsa>. This will replace the RSA_METHOD used by the RSA key and if the
|
|
previous method was supplied by an ENGINE, the handle to that ENGINE will
|
|
be released during the change. It is possible to have RSA keys that only
|
|
work with certain RSA_METHOD implementations (eg. from an ENGINE module
|
|
that supports embedded hardware-protected keys), and in such cases
|
|
attempting to change the RSA_METHOD for the key can have unexpected
|
|
results.
|
|
|
|
RSA_get_method() returns a pointer to the RSA_METHOD being used by B<rsa>.
|
|
This method may or may not be supplied by an ENGINE implementation, but if
|
|
it is, the return value can only be guaranteed to be valid as long as the
|
|
RSA key itself is valid and does not have its implementation changed by
|
|
RSA_set_method().
|
|
|
|
RSA_flags() returns the B<flags> that are set for B<rsa>'s current
|
|
RSA_METHOD. See the BUGS section.
|
|
|
|
RSA_new_method() allocates and initializes an RSA structure so that
|
|
B<engine> will be used for the RSA operations. If B<engine> is NULL, the
|
|
default ENGINE for RSA operations is used, and if no default ENGINE is set,
|
|
the RSA_METHOD controlled by RSA_set_default_method() is used.
|
|
|
|
RSA_flags() returns the B<flags> that are set for B<rsa>'s current method.
|
|
|
|
RSA_new_method() allocates and initializes an B<RSA> structure so that
|
|
B<method> will be used for the RSA operations. If B<method> is B<NULL>,
|
|
the default method is used.
|
|
|
|
=head1 THE RSA_METHOD STRUCTURE
|
|
|
|
typedef struct rsa_meth_st
|
|
{
|
|
/* name of the implementation */
|
|
const char *name;
|
|
|
|
/* encrypt */
|
|
int (*rsa_pub_enc)(int flen, unsigned char *from,
|
|
unsigned char *to, RSA *rsa, int padding);
|
|
|
|
/* verify arbitrary data */
|
|
int (*rsa_pub_dec)(int flen, unsigned char *from,
|
|
unsigned char *to, RSA *rsa, int padding);
|
|
|
|
/* sign arbitrary data */
|
|
int (*rsa_priv_enc)(int flen, unsigned char *from,
|
|
unsigned char *to, RSA *rsa, int padding);
|
|
|
|
/* decrypt */
|
|
int (*rsa_priv_dec)(int flen, unsigned char *from,
|
|
unsigned char *to, RSA *rsa, int padding);
|
|
|
|
/* compute r0 = r0 ^ I mod rsa->n (May be NULL for some
|
|
implementations) */
|
|
int (*rsa_mod_exp)(BIGNUM *r0, BIGNUM *I, RSA *rsa);
|
|
|
|
/* compute r = a ^ p mod m (May be NULL for some implementations) */
|
|
int (*bn_mod_exp)(BIGNUM *r, BIGNUM *a, const BIGNUM *p,
|
|
const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
|
|
|
|
/* called at RSA_new */
|
|
int (*init)(RSA *rsa);
|
|
|
|
/* called at RSA_free */
|
|
int (*finish)(RSA *rsa);
|
|
|
|
/* RSA_FLAG_EXT_PKEY - rsa_mod_exp is called for private key
|
|
* operations, even if p,q,dmp1,dmq1,iqmp
|
|
* are NULL
|
|
* RSA_METHOD_FLAG_NO_CHECK - don't check pub/private match
|
|
*/
|
|
int flags;
|
|
|
|
char *app_data; /* ?? */
|
|
|
|
int (*rsa_sign)(int type,
|
|
const unsigned char *m, unsigned int m_length,
|
|
unsigned char *sigret, unsigned int *siglen, const RSA *rsa);
|
|
int (*rsa_verify)(int dtype,
|
|
const unsigned char *m, unsigned int m_length,
|
|
const unsigned char *sigbuf, unsigned int siglen,
|
|
const RSA *rsa);
|
|
/* keygen. If NULL builtin RSA key generation will be used */
|
|
int (*rsa_keygen)(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb);
|
|
|
|
} RSA_METHOD;
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
RSA_PKCS1_OpenSSL(), RSA_PKCS1_null_method(), RSA_get_default_method()
|
|
and RSA_get_method() return pointers to the respective RSA_METHODs.
|
|
|
|
RSA_set_default_method() returns no value.
|
|
|
|
RSA_set_method() returns a pointer to the old RSA_METHOD implementation
|
|
that was replaced. However, this return value should probably be ignored
|
|
because if it was supplied by an ENGINE, the pointer could be invalidated
|
|
at any time if the ENGINE is unloaded (in fact it could be unloaded as a
|
|
result of the RSA_set_method() function releasing its handle to the
|
|
ENGINE). For this reason, the return type may be replaced with a B<void>
|
|
declaration in a future release.
|
|
|
|
RSA_new_method() returns NULL and sets an error code that can be obtained
|
|
by L<ERR_get_error(3)> if the allocation fails. Otherwise
|
|
it returns a pointer to the newly allocated structure.
|
|
|
|
=head1 BUGS
|
|
|
|
The behaviour of RSA_flags() is a mis-feature that is left as-is for now
|
|
to avoid creating compatibility problems. RSA functionality, such as the
|
|
encryption functions, are controlled by the B<flags> value in the RSA key
|
|
itself, not by the B<flags> value in the RSA_METHOD attached to the RSA key
|
|
(which is what this function returns). If the flags element of an RSA key
|
|
is changed, the changes will be honoured by RSA functionality but will not
|
|
be reflected in the return value of the RSA_flags() function - in effect
|
|
RSA_flags() behaves more like an RSA_default_flags() function (which does
|
|
not currently exist).
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<rsa(3)>, L<RSA_new(3)>
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
|
|
|
|
Licensed under the OpenSSL license (the "License"). You may not use
|
|
this file except in compliance with the License. You can obtain a copy
|
|
in the file LICENSE in the source distribution or at
|
|
L<https://www.openssl.org/source/license.html>.
|
|
|
|
=cut
|