Commit 5bf73873 authored by Geoff Thorpe's avatar Geoff Thorpe
Browse files

These are updates/fixes to DH/DSA/RAND docs based on the fixes to the RSA 

docs. There were a couple of other places (including RSA) where the docs
were not quite synchronised with the API that are now fixed. One or two
still remain to be fixed though ...
parent 415e03aa

doc/crypto/DH_set_method.pod

+60 −42
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 


=head1 NAME



DH_set_default_openssl_method, DH_get_default_openssl_method,

DH_set_default_method, DH_get_default_method,

DH_set_method, DH_new_method, DH_OpenSSL - select DH method



=head1 SYNOPSIS
@@ -10,45 +10,47 @@ DH_set_method, DH_new_method, DH_OpenSSL - select DH method 
 #include <openssl/dh.h>

 #include <openssl/engine.h>



 void DH_set_default_openssl_method(DH_METHOD *meth);

 void DH_set_default_method(const DH_METHOD *meth);



 DH_METHOD *DH_get_default_openssl_method(void);

 const DH_METHOD *DH_get_default_method(void);



 int DH_set_method(DH *dh, ENGINE *engine);

 int DH_set_method(DH *dh, const DH_METHOD *meth);



 DH *DH_new_method(ENGINE *engine);



 DH_METHOD *DH_OpenSSL(void);

 const DH_METHOD *DH_OpenSSL(void);



=head1 DESCRIPTION



A B<DH_METHOD> specifies the functions that OpenSSL uses for Diffie-Hellman

operations. By modifying the method, alternative implementations

such as hardware accelerators may be used.



Initially, the default is to use the OpenSSL internal implementation.

DH_OpenSSL() returns a pointer to that method.



DH_set_default_openssl_method() makes B<meth> the default method for all DH

structures created later. B<NB:> This is true only whilst the default engine

for Diffie-Hellman operations remains as "openssl". ENGINEs provide an

encapsulation for implementations of one or more algorithms, and all the DH

functions mentioned here operate within the scope of the default

"openssl" engine.



DH_get_default_openssl_method() returns a pointer to the current default

method for the "openssl" engine.



DH_set_method() selects B<engine> as the engine that will be responsible for

all operations using the structure B<dh>. If this function completes successfully,

then the B<dh> structure will have its own functional reference of B<engine>, so

the caller should remember to free their own reference to B<engine> when they are

finished with it. NB: An ENGINE's DH_METHOD can be retrieved (or set) by

ENGINE_get_DH() or ENGINE_set_DH().



DH_new_method() allocates and initializes a DH structure so that

B<engine> will be used for the DH operations. If B<engine> is NULL,

the default engine for Diffie-Hellman opertaions is used.

such as hardware accelerators may be used. IMPORTANT: See the NOTES section for

important information about how these DH API functions are affected by the use

of B<ENGINE> API calls.



Initially, the default DH_METHOD is the OpenSSL internal implementation, as

returned by DH_OpenSSL().



DH_set_default_method() makes B<meth> the default method for all DH

structures created later. B<NB>: This is true only whilst no ENGINE has been set

as a default for DH, so this function is no longer recommended.



DH_get_default_method() returns a pointer to the current default DH_METHOD.

However, the meaningfulness of this result is dependant on whether the ENGINE

API is being used, so this function is no longer recommended.



DH_set_method() selects B<meth> to perform all operations using the key B<dh>.

This will replace the DH_METHOD used by the DH 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 DH keys that only work with certain DH_METHOD

implementations (eg. from an ENGINE module that supports embedded

hardware-protected keys), and in such cases attempting to change the DH_METHOD

for the key can have unexpected results.



DH_new_method() allocates and initializes a DH structure so that B<engine> will

be used for the DH operations. If B<engine> is NULL, the default ENGINE for DH

operations is used, and if no default ENGINE is set, the DH_METHOD controlled by

DH_set_default_method() is used.



=head1 THE DH_METHOD STRUCTURE
@@ -82,17 +84,28 @@ the default engine for Diffie-Hellman opertaions is used. 


=head1 RETURN VALUES



DH_OpenSSL() and DH_get_default_openssl_method() return pointers to the

respective B<DH_METHOD>s.

DH_OpenSSL() and DH_get_default_method() return pointers to the respective

B<DH_METHOD>s.



DH_set_default_method() returns no value.



DH_set_method() returns non-zero if the provided B<meth> was successfully set as

the method for B<dh> (including unloading the ENGINE handle if the previous

method was supplied by an ENGINE).



DH_set_default_openssl_method() returns no value.

DH_new_method() returns NULL and sets an error code that can be obtained by

L<ERR_get_error(3)|ERR_get_error(3)> if the allocation fails. Otherwise it

returns a pointer to the newly allocated structure.



DH_set_method() returns non-zero if the ENGINE associated with B<dh>

was successfully changed to B<engine>.

=head1 NOTES



DH_new_method() returns NULL and sets an error code that can be

obtained by L<ERR_get_error(3)|ERR_get_error(3)> if the allocation fails.

Otherwise it returns a pointer to the newly allocated structure.

As of version 0.9.7, DH_METHOD implementations are grouped together with other

algorithmic APIs (eg. RSA_METHOD, EVP_CIPHER, etc) in B<ENGINE> modules. If a

default ENGINE is specified for DH functionality using an ENGINE API function,

that will override any DH defaults set using the DH API (ie.

DH_set_default_method()). For this reason, the ENGINE API is the recommended way

to control default implementations for use in DH and other cryptographic

algorithms.



=head1 SEE ALSO
@@ -103,9 +116,14 @@ L<dh(3)|dh(3)>, L<DH_new(3)|DH_new(3)> 
DH_set_default_method(), DH_get_default_method(), DH_set_method(),

DH_new_method() and DH_OpenSSL() were added in OpenSSL 0.9.4.



DH_set_default_openssl_method() and DH_get_default_openssl_method()

replaced DH_set_default_method() and DH_get_default_method() respectively,

and DH_set_method() and DH_new_method() were altered to use B<ENGINE>s

rather than B<DH_METHOD>s during development of OpenSSL 0.9.6.

DH_set_default_openssl_method() and DH_get_default_openssl_method() replaced

DH_set_default_method() and DH_get_default_method() respectively, and

DH_set_method() and DH_new_method() were altered to use B<ENGINE>s rather than

B<DH_METHOD>s during development of the engine version of OpenSSL 0.9.6. For

0.9.7, the handling of defaults in the ENGINE API was restructured so that this

change was reversed, and behaviour of the other functions resembled more closely

the previous behaviour. The behaviour of defaults in the ENGINE API now

transparently overrides the behaviour of defaults in the DH API without

requiring changing these function prototypes.



=cut

doc/crypto/DSA_dup_DH.pod

+1 −1
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ DSA_dup_DH - create a DH structure out of DSA structure 


 #include <openssl/dsa.h>



 DH * DSA_dup_DH(DSA *r);

 DH * DSA_dup_DH(const DSA *r);



=head1 DESCRIPTION

doc/crypto/DSA_new.pod

+2 −1
Original line number Diff line number Diff line
@@ -14,7 +14,8 @@ DSA_new, DSA_free - allocate and free DSA objects 


=head1 DESCRIPTION



DSA_new() allocates and initializes a B<DSA> structure.

DSA_new() allocates and initializes a B<DSA> structure. It is equivalent to

calling DSA_new_method(NULL).



DSA_free() frees the B<DSA> structure and its components. The values are

erased before the memory is returned to the system.

doc/crypto/DSA_set_method.pod

+58 −33
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 


=head1 NAME



DSA_set_default_openssl_method, DSA_get_default_openssl_method,

DSA_set_default_method, DSA_get_default_method,

DSA_set_method, DSA_new_method, DSA_OpenSSL - select DSA method



=head1 SYNOPSIS
@@ -10,11 +10,11 @@ DSA_set_method, DSA_new_method, DSA_OpenSSL - select DSA method 
 #include <openssl/dsa.h>

 #include <openssl/engine.h>



 void DSA_set_default_openssl_method(DSA_METHOD *meth);

 void DSA_set_default_method(const DSA_METHOD *meth);



 DSA_METHOD *DSA_get_default_openssl_method(void);

 const DSA_METHOD *DSA_get_default_method(void);



 int DSA_set_method(DSA *dsa, ENGINE *engine);

 int DSA_set_method(DSA *dsa, const DSA_METHOD *meth);



 DSA *DSA_new_method(ENGINE *engine);
@@ -24,26 +24,35 @@ DSA_set_method, DSA_new_method, DSA_OpenSSL - select DSA method 


A B<DSA_METHOD> specifies the functions that OpenSSL uses for DSA

operations. By modifying the method, alternative implementations

such as hardware accelerators may be used.



Initially, the default is to use the OpenSSL internal implementation.

DSA_OpenSSL() returns a pointer to that method.



DSA_set_default_openssl_method() makes B<meth> the default method for

all DSA structures created later. B<NB:> This is true only whilst the

default engine for DSA operations remains as "openssl". ENGINEs

provide an encapsulation for implementations of one or more algorithms at a

time, and all the DSA functions mentioned here operate within the scope

of the default "openssl" engine.



DSA_get_default_openssl_method() returns a pointer to the current default

method for the "openssl" engine.



DSA_set_method() selects B<engine> for all operations using the structure B<dsa>.



DSA_new_method() allocates and initializes a DSA structure so that

B<engine> will be used for the DSA operations. If B<engine> is NULL,

the default engine for DSA operations is used.

such as hardware accelerators may be used. IMPORTANT: See the NOTES section for

important information about how these DSA API functions are affected by the use

of B<ENGINE> API calls.



Initially, the default DSA_METHOD is the OpenSSL internal implementation,

as returned by DSA_OpenSSL().



DSA_set_default_method() makes B<meth> the default method for all DSA

structures created later. B<NB>: This is true only whilst no ENGINE has

been set as a default for DSA, so this function is no longer recommended.



DSA_get_default_method() returns a pointer to the current default

DSA_METHOD. However, the meaningfulness of this result is dependant on

whether the ENGINE API is being used, so this function is no longer 

recommended.



DSA_set_method() selects B<meth> to perform all operations using the key

B<rsa>. This will replace the DSA_METHOD used by the DSA 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 DSA keys that only

work with certain DSA_METHOD implementations (eg. from an ENGINE module

that supports embedded hardware-protected keys), and in such cases

attempting to change the DSA_METHOD for the key can have unexpected

results.



DSA_new_method() allocates and initializes a DSA structure so that B<engine>

will be used for the DSA operations. If B<engine> is NULL, the default engine

for DSA operations is used, and if no default ENGINE is set, the DSA_METHOD

controlled by DSA_set_default_method() is used.



=head1 THE DSA_METHOD STRUCTURE
@@ -89,18 +98,29 @@ struct 


=head1 RETURN VALUES



DSA_OpenSSL() and DSA_get_default_openssl_method() return pointers to the

respective B<DSA_METHOD>s.

DSA_OpenSSL() and DSA_get_default_method() return pointers to the respective

B<DSA_METHOD>s.



DSA_set_default_openssl_method() returns no value.

DSA_set_default_method() returns no value.



DSA_set_method() returns non-zero if the ENGINE associated with B<dsa>

was successfully changed to B<engine>.

DSA_set_method() returns non-zero if the provided B<meth> was successfully set as

the method for B<dsa> (including unloading the ENGINE handle if the previous

method was supplied by an ENGINE).



DSA_new_method() returns NULL and sets an error code that can be

obtained by L<ERR_get_error(3)|ERR_get_error(3)> if the allocation

fails. Otherwise it returns a pointer to the newly allocated structure.



=head1 NOTES



As of version 0.9.7, DSA_METHOD implementations are grouped together with other

algorithmic APIs (eg. RSA_METHOD, EVP_CIPHER, etc) in B<ENGINE> modules. If a

default ENGINE is specified for DSA functionality using an ENGINE API function,

that will override any DSA defaults set using the DSA API (ie.

DSA_set_default_method()). For this reason, the ENGINE API is the recommended way

to control default implementations for use in DSA and other cryptographic

algorithms.



=head1 SEE ALSO



L<dsa(3)|dsa(3)>, L<DSA_new(3)|DSA_new(3)>
@@ -110,9 +130,14 @@ L<dsa(3)|dsa(3)>, L<DSA_new(3)|DSA_new(3)> 
DSA_set_default_method(), DSA_get_default_method(), DSA_set_method(),

DSA_new_method() and DSA_OpenSSL() were added in OpenSSL 0.9.4.



DSA_set_default_openssl_method() and DSA_get_default_openssl_method()

replaced DSA_set_default_method() and DSA_get_default_method() respectively,

and DSA_set_method() and DSA_new_method() were altered to use B<ENGINE>s

rather than B<DSA_METHOD>s during development of OpenSSL 0.9.6.

DSA_set_default_openssl_method() and DSA_get_default_openssl_method() replaced

DSA_set_default_method() and DSA_get_default_method() respectively, and

DSA_set_method() and DSA_new_method() were altered to use B<ENGINE>s rather than

B<DSA_METHOD>s during development of the engine version of OpenSSL 0.9.6. For

0.9.7, the handling of defaults in the ENGINE API was restructured so that this

change was reversed, and behaviour of the other functions resembled more closely

the previous behaviour. The behaviour of defaults in the ENGINE API now

transparently overrides the behaviour of defaults in the DSA API without

requiring changing these function prototypes.



=cut

doc/crypto/DSA_size.pod

+1 −1
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ DSA_size - get DSA signature size 


 #include <openssl/dsa.h>



 int DSA_size(DSA *dsa);

 int DSA_size(const DSA *dsa);



=head1 DESCRIPTION