=head1 SYNOPSIS
-=for comment multiple includes
+=for openssl multiple includes
- #include <openssl/core_numbers.h>
+ #include <openssl/core_dispatch.h>
#include <openssl/core_names.h>
/*
*/
/* Context management */
- void *OP_keyexch_newctx(void *provctx);
- void OP_keyexch_freectx(void *ctx);
- void *OP_keyexch_dupctx(void *ctx);
+ void *OSSL_FUNC_keyexch_newctx(void *provctx);
+ void OSSL_FUNC_keyexch_freectx(void *ctx);
+ void *OSSL_FUNC_keyexch_dupctx(void *ctx);
/* Shared secret derivation */
- int OP_keyexch_init(void *ctx, void *provkey);
- int OP_keyexch_set_peer(void *ctx, void *provkey);
- int OP_keyexch_derive(void *ctx, unsigned char *secret, size_t *secretlen,
- size_t outlen);
+ int OSSL_FUNC_keyexch_init(void *ctx, void *provkey,
+ const OSSL_PARAM params[]);
+ int OSSL_FUNC_keyexch_set_peer(void *ctx, void *provkey);
+ int OSSL_FUNC_keyexch_derive(void *ctx, unsigned char *secret, size_t *secretlen,
+ size_t outlen);
/* Key Exchange parameters */
- int OP_keyexch_set_ctx_params(void *ctx, const OSSL_PARAM params[]);
- const OSSL_PARAM *OP_keyexch_settable_ctx_params(void);
+ int OSSL_FUNC_keyexch_set_ctx_params(void *ctx, const OSSL_PARAM params[]);
+ const OSSL_PARAM *OSSL_FUNC_keyexch_settable_ctx_params(void *ctx,
+ void *provctx);
+ int OSSL_FUNC_keyexch_get_ctx_params(void *ctx, OSSL_PARAM params[]);
+ const OSSL_PARAM *OSSL_FUNC_keyexch_gettable_ctx_params(void *ctx,
+ void *provctx);
=head1 DESCRIPTION
for further information.
The key exchange (OSSL_OP_KEYEXCH) operation enables providers to implement key
-exchange algorithms and make them available to applications via the API
-functions L<EVP_PKEY_derive_init_ex(3)>, and L<EVP_PKEY_derive(3)> (as well as
+exchange algorithms and make them available to applications via
+L<EVP_PKEY_derive(3)> and
other related functions).
All "functions" mentioned here are passed as function pointers between
-F<libcrypto> and the provider in B<OSSL_DISPATCH> arrays via
-B<OSSL_ALGORITHM> arrays that are returned by the provider's
+F<libcrypto> and the provider in L<OSSL_DISPATCH(3)> arrays via
+L<OSSL_ALGORITHM(3)> arrays that are returned by the provider's
provider_query_operation() function
(see L<provider-base(7)/Provider Functions>).
All these "functions" have a corresponding function type definition
-named B<OSSL_{name}_fn>, and a helper function to retrieve the
-function pointer from an B<OSSL_DISPATCH> element named
-B<OSSL_get_{name}>.
-For example, the "function" OP_keyexch_newctx() has these:
+named B<OSSL_FUNC_{name}_fn>, and a helper function to retrieve the
+function pointer from an L<OSSL_DISPATCH(3)> element named
+B<OSSL_FUNC_{name}>.
+For example, the "function" OSSL_FUNC_keyexch_newctx() has these:
- typedef void *(OSSL_OP_keyexch_newctx_fn)(void *provctx);
- static ossl_inline OSSL_OP_keyexch_newctx_fn
- OSSL_get_OP_keyexch_newctx(const OSSL_DISPATCH *opf);
+ typedef void *(OSSL_FUNC_keyexch_newctx_fn)(void *provctx);
+ static ossl_inline OSSL_FUNC_keyexch_newctx_fn
+ OSSL_FUNC_keyexch_newctx(const OSSL_DISPATCH *opf);
-B<OSSL_DISPATCH> arrays are indexed by numbers that are provided as
-macros in L<openssl-core_numbers.h(7)>, as follows:
+L<OSSL_DISPATCH(3)> arrays are indexed by numbers that are provided as
+macros in L<openssl-core_dispatch.h(7)>, as follows:
- OP_keyexch_newctx OSSL_FUNC_KEYEXCH_NEWCTX
- OP_keyexch_freectx OSSL_FUNC_KEYEXCH_FREECTX
- OP_keyexch_dupctx OSSL_FUNC_KEYEXCH_DUPCTX
+ OSSL_FUNC_keyexch_newctx OSSL_FUNC_KEYEXCH_NEWCTX
+ OSSL_FUNC_keyexch_freectx OSSL_FUNC_KEYEXCH_FREECTX
+ OSSL_FUNC_keyexch_dupctx OSSL_FUNC_KEYEXCH_DUPCTX
- OP_keyexch_init OSSL_FUNC_KEYEXCH_INIT
- OP_keyexch_set_peer OSSL_FUNC_KEYEXCH_SET_PEER
- OP_keyexch_derive OSSL_FUNC_KEYEXCH_DERIVE
+ OSSL_FUNC_keyexch_init OSSL_FUNC_KEYEXCH_INIT
+ OSSL_FUNC_keyexch_set_peer OSSL_FUNC_KEYEXCH_SET_PEER
+ OSSL_FUNC_keyexch_derive OSSL_FUNC_KEYEXCH_DERIVE
- OP_keyexch_set_ctx_params OSSL_FUNC_KEYEXCH_SET_CTX_PARAMS
- OP_keyexch_settable_ctx_params OSSL_FUNC_KEYEXCH_SETTABLE_CTX_PARAMS
+ OSSL_FUNC_keyexch_set_ctx_params OSSL_FUNC_KEYEXCH_SET_CTX_PARAMS
+ OSSL_FUNC_keyexch_settable_ctx_params OSSL_FUNC_KEYEXCH_SETTABLE_CTX_PARAMS
+ OSSL_FUNC_keyexch_get_ctx_params OSSL_FUNC_KEYEXCH_GET_CTX_PARAMS
+ OSSL_FUNC_keyexch_gettable_ctx_params OSSL_FUNC_KEYEXCH_GETTABLE_CTX_PARAMS
A key exchange algorithm implementation may not implement all of these functions.
In order to be a consistent set of functions a provider must implement
-OP_keyexch_newctx, OP_keyexch_freectx, OP_keyexch_init and OP_keyexch_derive.
+OSSL_FUNC_keyexch_newctx, OSSL_FUNC_keyexch_freectx, OSSL_FUNC_keyexch_init and OSSL_FUNC_keyexch_derive.
All other functions are optional.
A key exchange algorithm must also implement some mechanism for generating,
=head2 Context Management Functions
-OP_keyexch_newctx() should create and return a pointer to a provider side
+OSSL_FUNC_keyexch_newctx() should create and return a pointer to a provider side
structure for holding context information during a key exchange operation.
A pointer to this context will be passed back in a number of the other key
exchange operation function calls.
-The param
ater I<provctx> is the provider context generated during provider
-initialisation (see L<provider(3)>).
+The param
eter I<provctx> is the provider context generated during provider
+initialisation (see L<provider(7)>).
-OP_keyexch_freectx() is passed a pointer to the provider side key exchange
+OSSL_FUNC_keyexch_freectx() is passed a pointer to the provider side key exchange
context in the I<ctx> parameter.
This function should free any resources associated with that context.
-OP_keyexch_dupctx() should duplicate the provider side key exchange context in
+OSSL_FUNC_keyexch_dupctx() should duplicate the provider side key exchange context in
the I<ctx> parameter and return the duplicate copy.
=head2 Shared Secret Derivation Functions
-OP_keyexch_init() initialises a key exchange operation given a provider side key
-exchange context in the I<ctx> paramter, and a pointer to a provider key object
-in the I<provkey> parameter. The key object should have been previously
+OSSL_FUNC_keyexch_init() initialises a key exchange operation given a provider side key
+exchange context in the I<ctx> parameter, and a pointer to a provider key object
+in the I<provkey> parameter.
+The I<params>, if not NULL, should be set on the context in a manner similar to
+using OSSL_FUNC_keyexch_set_params().
+The key object should have been previously
generated, loaded or imported into the provider using the key management
(OSSL_OP_KEYMGMT) operation (see provider-keymgmt(7)>.
-OP_keyexch_set_peer() is called to supply the peer's public key (in the
+OSSL_FUNC_keyexch_set_peer() is called to supply the peer's public key (in the
I<provkey> parameter) to be used when deriving the shared secret.
It is also passed a previously initialised key exchange context in the I<ctx>
parameter.
the provider using the key management (OSSL_OP_KEYMGMT) operation (see
provider-keymgmt(7)>.
-OP_keyexch_derive() performs the actual key exchange itself by deriving a shared
+OSSL_FUNC_keyexch_derive() performs the actual key exchange itself by deriving a shared
secret.
A previously initialised key exchange context is passed in the I<ctx>
parameter.
If I<secret> is NULL then the maximum length of the shared secret should be
written to I<*secretlen>.
-=head2 Key Exchange Parameters
+=head2 Key Exchange Parameters Functions
-See L<OSSL_PARAM(3)> for further details on the parameters structure used by
-the OP_keyexch_set_params() function.
-
-OP_keyexch_set_ctx_params() sets key exchange parameters associated with the
-given provider side key exchange context I<ctx> to I<params>.
+OSSL_FUNC_keyexch_set_ctx_params() sets key exchange parameters associated with the
+given provider side key exchange context I<ctx> to I<params>,
+see L</Common Key Exchange parameters>.
Any parameter settings are additional to any that were previously set.
+Passing NULL for I<params> should return true.
+
+OSSL_FUNC_keyexch_get_ctx_params() gets key exchange parameters associated with the
+given provider side key exchange context I<ctx> into I<params>,
+see L</Common Key Exchange parameters>.
+Passing NULL for I<params> should return true.
+
+OSSL_FUNC_keyexch_settable_ctx_params() yields a constant L<OSSL_PARAM(3)> array that
+describes the settable parameters, i.e. parameters that can be used with
+OP_signature_set_ctx_params().
+If OSSL_FUNC_keyexch_settable_ctx_params() is present, OSSL_FUNC_keyexch_set_ctx_params() must
+also be present, and vice versa.
+Similarly, OSSL_FUNC_keyexch_gettable_ctx_params() yields a constant L<OSSL_PARAM(3)>
+array that describes the gettable parameters, i.e. parameters that can be
+handled by OP_signature_get_ctx_params().
+If OSSL_FUNC_keyexch_gettable_ctx_params() is present, OSSL_FUNC_keyexch_get_ctx_params() must
+also be present, and vice versa.
+
+Notice that not all settable parameters are also gettable, and vice versa.
-Parameters currently recognised by built-in key exchange algorithms are as
-follows.
-Not all parameters are relevant to, or are understood by all key exchange
-algorithms:
+=head2 Common Key Exchange parameters
+
+See L<OSSL_PARAM(3)> for further details on the parameters structure used by
+the OSSL_FUNC_keyexch_set_ctx_params() and OSSL_FUNC_keyexch_get_ctx_params() functions.
+
+Common parameters currently recognised by built-in key exchange algorithms are
+as follows.
=over 4
-=item "pad" (B<OSSL_EXCHANGE_PARAM_PAD>) <unsigned integer>
+=item "kdf-type" (B<OSSL_EXCHANGE_PARAM_KDF_TYPE>) <UTF8 string>
-Sets the padding mode for the associated key exchange ctx.
-Setting a value of 1 will turn padding on.
-Setting a vlue of 0 will turn padding off.
-If padding is off then the derived shared secret may be smaller than the largest
-possible secret size.
-If padding is on then the derived shared secret will have its first bytes filled
-with 0s where necessary to make the shared secret the same size as the largest
-possible secret size.
+Sets or gets the Key Derivation Function type to apply within the associated key
+exchange ctx.
-=back
+=item "kdf-digest" (B<OSSL_EXCHANGE_PARAM_KDF_DIGEST>) <UTF8 string>
-OP_keyexch_settable_ctx_params() gets a constant B<OSSL_PARAM> array that
-decribes the settable parameters, i.e. parameters that can be used with
-OP_signature_set_ctx_params().
-See L<OSSL_PARAM(3)> for the use of B<OSSL_PARAM> as parameter descriptor.
+Sets or gets the Digest algorithm to be used as part of the Key Derivation Function
+associated with the given key exchange ctx.
+
+=item "kdf-digest-props" (B<OSSL_EXCHANGE_PARAM_KDF_DIGEST_PROPS>) <UTF8 string>
+
+Sets properties to be used upon look up of the implementation for the selected
+Digest algorithm for the Key Derivation Function associated with the given key
+exchange ctx.
+
+=item "kdf-outlen" (B<OSSL_EXCHANGE_PARAM_KDF_OUTLEN>) <unsigned integer>
+
+Sets or gets the desired size for the output of the chosen Key Derivation Function
+associated with the given key exchange ctx.
+The length of the "kdf-outlen" parameter should not exceed that of a B<size_t>.
+
+=item "kdf-ukm" (B<OSSL_EXCHANGE_PARAM_KDF_UKM>) <octet string>
+
+Sets the User Key Material to be used as part of the selected Key Derivation
+Function associated with the given key exchange ctx.
+
+=item "kdf-ukm" (B<OSSL_EXCHANGE_PARAM_KDF_UKM>) <octet string ptr>
+
+Gets a pointer to the User Key Material to be used as part of the selected
+Key Derivation Function associated with the given key exchange ctx. Providers
+usually do not need to support this gettable parameter as its sole purpose
+is to support functionality of the deprecated EVP_PKEY_CTX_get0_ecdh_kdf_ukm()
+and EVP_PKEY_CTX_get0_dh_kdf_ukm() functions.
+
+=back
=head1 RETURN VALUES
-OP_keyexch_newctx() and OP_keyexch_dupctx() should return the newly created
+OSSL_FUNC_keyexch_newctx() and OSSL_FUNC_keyexch_dupctx() should return the newly created
provider side key exchange context, or NULL on failure.
-OP_keyexch_init(), OP_keyexch_set_peer(), OP_keyexch_derive() and
-OP_keyexch_set_params() should return 1 for success or 0 on error.
+OSSL_FUNC_keyexch_init(), OSSL_FUNC_keyexch_set_peer(), OSSL_FUNC_keyexch_derive(),
+OSSL_FUNC_keyexch_set_params(), and OSSL_FUNC_keyexch_get_params() should return 1 for success
+or 0 on error.
+
+OSSL_FUNC_keyexch_settable_ctx_params() and OSSL_FUNC_keyexch_gettable_ctx_params() should
+always return a constant L<OSSL_PARAM(3)> array.
=head1 SEE ALSO
=head1 COPYRIGHT
-Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
projects / openssl.git / blobdiff