diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/man3/EVP_KEM_free.pod | 82 | ||||
| -rw-r--r-- | doc/man3/EVP_PKEY_CTX_ctrl.pod | 13 | ||||
| -rw-r--r-- | doc/man3/EVP_PKEY_decapsulate.pod | 99 | ||||
| -rw-r--r-- | doc/man3/EVP_PKEY_encapsulate.pod | 101 | ||||
| -rw-r--r-- | doc/man7/EVP_KEM-RSA.pod | 66 | ||||
| -rw-r--r-- | doc/man7/OSSL_PROVIDER-FIPS.pod | 8 | ||||
| -rw-r--r-- | doc/man7/OSSL_PROVIDER-default.pod | 8 | ||||
| -rw-r--r-- | doc/man7/provider-kem.pod | 207 | ||||
| -rw-r--r-- | doc/man7/provider.pod | 6 |
9 files changed, 589 insertions, 1 deletions
diff --git a/doc/man3/EVP_KEM_free.pod b/doc/man3/EVP_KEM_free.pod new file mode 100644 index 0000000000..0e3ca12ae3 --- /dev/null +++ b/doc/man3/EVP_KEM_free.pod @@ -0,0 +1,82 @@ +=pod + +=head1 NAME + +EVP_KEM_fetch, EVP_KEM_free, EVP_KEM_up_ref, +EVP_KEM_number, EVP_KEM_is_a, EVP_KEM_provider, +EVP_KEM_do_all_provided, EVP_KEM_names_do_all +- Functions to manage EVP_KEM algorithm objects + +=head1 SYNOPSIS + + #include <openssl/evp.h> + + EVP_KEM *EVP_KEM_fetch(OPENSSL_CTX *ctx, const char *algorithm, + const char *properties); + void EVP_KEM_free(EVP_KEM *kem); + int EVP_KEM_up_ref(EVP_KEM *kem); + int EVP_KEM_number(const EVP_KEM *kem); + int EVP_KEM_is_a(const EVP_KEM *kem, const char *name); + OSSL_PROVIDER *EVP_KEM_provider(const EVP_KEM *kem); + void EVP_KEM_do_all_provided(OPENSSL_CTX *libctx, + void (*fn)(EVP_KEM *kem, void *arg), void *arg); + void EVP_KEM_names_do_all(const EVP_KEM *kem, + void (*fn)(const char *name, void *data), void *data); + +=head1 DESCRIPTION + +EVP_KEM_fetch() fetches the implementation for the given B<algorithm> from any +provider offering it, within the criteria given by the B<properties> and in the +scope of the given library context B<ctx> (see L<OPENSSL_CTX(3)>). The algorithm +will be one offering functions for performing asymmetric kem related tasks such +as key encapsulation and decapsulation. +See L<provider(7)/Fetching algorithms> for further information. + +The returned value must eventually be freed with EVP_KEM_free(). + +EVP_KEM_free() decrements the reference count for the B<EVP_KEM> structure. +Typically this structure will have been obtained from an earlier call to +EVP_KEM_fetch(). If the reference count drops to 0 then the structure is freed. + +EVP_KEM_up_ref() increments the reference count for an B<EVP_KEM> structure. + +EVP_KEM_is_a() returns 1 if I<kem> is an implementation of an +algorithm that's identifiable with I<name>, otherwise 0. + +EVP_KEM_provider() returns the provider that I<kem> was fetched from. + +EVP_KEM_do_all_provided() traverses all EVP_KEMs implemented by all activated +providers in the given library context I<libctx>, and for each of the +implementations, calls the given function I<fn> with the implementation method +and the given I<arg> as argument. + +EVP_KEM_number() returns the internal dynamic number assigned to I<kem>. + +EVP_KEM_names_do_all() traverses all names for I<kem>, and calls I<fn> with +each name and I<data>. + +=head1 RETURN VALUES + +EVP_KEM_fetch() returns a pointer to an B<EVP_KEM> for success or B<NULL> for +failure. + +EVP_KEM_up_ref() returns 1 for success or 0 otherwise. + +=head1 SEE ALSO + +L<provider(7)/Fetching algorithms>, L<OSSL_PROVIDER(3)> + +=head1 HISTORY + +The functions described here were added in OpenSSL 3.0. + +=head1 COPYRIGHT + +Copyright 2020 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 +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut diff --git a/doc/man3/EVP_PKEY_CTX_ctrl.pod b/doc/man3/EVP_PKEY_CTX_ctrl.pod index 794ad2053a..e5c187d950 100644 --- a/doc/man3/EVP_PKEY_CTX_ctrl.pod +++ b/doc/man3/EVP_PKEY_CTX_ctrl.pod @@ -67,7 +67,8 @@ EVP_PKEY_CTX_set_ecdh_kdf_outlen, EVP_PKEY_CTX_get_ecdh_kdf_outlen, EVP_PKEY_CTX_set0_ecdh_kdf_ukm, EVP_PKEY_CTX_get0_ecdh_kdf_ukm, -EVP_PKEY_CTX_set1_id, EVP_PKEY_CTX_get1_id, EVP_PKEY_CTX_get1_id_len +EVP_PKEY_CTX_set1_id, EVP_PKEY_CTX_get1_id, EVP_PKEY_CTX_get1_id_len, +EVP_PKEY_CTX_set_kem_op - algorithm specific control operations =head1 SYNOPSIS @@ -91,6 +92,8 @@ EVP_PKEY_CTX_set1_id, EVP_PKEY_CTX_get1_id, EVP_PKEY_CTX_get1_id_len int EVP_PKEY_CTX_set_group_name(EVP_PKEY_CTX *ctx, const char *name); int EVP_PKEY_CTX_get_group_name(EVP_PKEY_CTX *ctx, char *name, size_t namelen); + int EVP_PKEY_CTX_set_kem_op(EVP_PKEY_CTX *ctx, const char *op); + #include <openssl/rsa.h> int EVP_PKEY_CTX_set_rsa_padding(EVP_PKEY_CTX *ctx, int pad); @@ -606,6 +609,12 @@ memory for further calls to EVP_PKEY_CTX_get1_id(). EVP_PKEY_CTX_get1_id() returns the previously set ID value to caller in I<id>. The caller should allocate adequate memory space for the I<id> before calling EVP_PKEY_CTX_get1_id(). +EVP_PKEY_CTX_set_kem_op() sets the KEM operation to run. This can be set after +EVP_PKEY_encapsulate_init() or EVP_PKEY_decapsulate_init() to select the +kem operation. RSA is the only key type that supports encapsulation currently, +and as there is no default operation for the RSA type, this function must be +called before EVP_PKEY_encapsulate() or EVP_PKEY_decapsulate(). + =head1 RETURN VALUES All other functions described on this page return a positive value for success @@ -623,6 +632,8 @@ L<EVP_PKEY_verify(3)>, L<EVP_PKEY_verify_recover(3)>, L<EVP_PKEY_derive(3)>, L<EVP_PKEY_keygen(3)> +L<EVP_PKEY_encapsulate(3)> +L<EVP_PKEY_decapsulate(3)> =head1 HISTORY diff --git a/doc/man3/EVP_PKEY_decapsulate.pod b/doc/man3/EVP_PKEY_decapsulate.pod new file mode 100644 index 0000000000..7dd47a1e58 --- /dev/null +++ b/doc/man3/EVP_PKEY_decapsulate.pod @@ -0,0 +1,99 @@ +=pod + +=head1 NAME + +EVP_PKEY_decapsulate_init, EVP_PKEY_decapsulate +- Key decapsulation using a private key algorithm + +=head1 SYNOPSIS + + #include <openssl/evp.h> + + int EVP_PKEY_decapsulate_init(EVP_PKEY_CTX *ctx); + int EVP_PKEY_decapsulate(EVP_PKEY_CTX *ctx, + unsigned char *secret, size_t *secretlen, + const unsigned char *wrapped, size_t wrappedlen); + +=head1 DESCRIPTION + +The EVP_PKEY_decapsulate_init() function initializes a private key algorithm +context I<ctx> for a decapsulation operation. + +The EVP_PKEY_decapsulate() function performs a private key decapsulation +operation using I<ctx>. The data to be decapsulated is specified using the +I<wrapped> and I<wrappedlen> parameters. +If I<secret> is I<NULL> then the maximum size of the output secret buffer +is written to the I<*secretlen> parameter. If I<secret> is not B<NULL> and the +call is successful then the decapsulated secret data is written to I<secret> and +the amount of data written to I<secretlen>. + +=head1 NOTES + +After the call to EVP_PKEY_decapsulate_init() algorithm specific parameters +for the operation may be set using L<EVP_PKEY_CTX_set_params(3)>. There are no +settable parameters currently. + +=head1 RETURN VALUES + +EVP_PKEY_decapsulate_init() and EVP_PKEY_decapsulate() return 1 for +success and 0 or a negative value for failure. In particular a return value of -2 +indicates the operation is not supported by the private key algorithm. + +=head1 EXAMPLES + +Decapsulate data using RSA: + + #include <openssl/evp.h> + + /* + * NB: assumes rsa_priv_key is an RSA private key, + * and that in, inlen are already set up to contain encapsulated data. + */ + + EVP_PKEY_CTX *ctx = NULL; + size_t secretlen = 0; + unsigned char *secret = NULL;; + + ctx = EVP_PKEY_CTX_new_from_pkey(libctx, rsa_priv_key, NULL); + if (ctx = NULL) + /* Error */ + if (EVP_PKEY_decapsulate_init(ctx) <= 0) + /* Error */ + + /* Set the mode - only 'RSASVE' is currently supported */ + if (EVP_PKEY_CTX_set_kem_op(ctx, "RSASVE") <= 0) + /* Error */ + + /* Determine buffer length */ + if (EVP_PKEY_decapsulate(ctx, NULL, &secretlen, in, inlen) <= 0) + /* Error */ + + secret = OPENSSL_malloc(secretlen); + if (secret == NULL) + /* malloc failure */ + + /* Decapsulated secret data is secretlen bytes long */ + if (EVP_PKEY_decapsulaterctx, secret, &secretlen, in, inlen) <= 0) + /* Error */ + + +=head1 SEE ALSO + +L<EVP_PKEY_CTX_new(3)>, +L<EVP_PKEY_encapsulate(3)>, +L<EVP_KEM-RSA(7)>, + +=head1 HISTORY + +These functions were added in OpenSSL 3.0. + +=head1 COPYRIGHT + +Copyright 2020 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 +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut diff --git a/doc/man3/EVP_PKEY_encapsulate.pod b/doc/man3/EVP_PKEY_encapsulate.pod new file mode 100644 index 0000000000..0e911f71cf --- /dev/null +++ b/doc/man3/EVP_PKEY_encapsulate.pod @@ -0,0 +1,101 @@ +=pod + +=head1 NAME + +EVP_PKEY_encapsulate_init, EVP_PKEY_encapsulate +- Key encapsulation using a public key algorithm + +=head1 SYNOPSIS + + #include <openssl/evp.h> + + int EVP_PKEY_encapsulate_init(EVP_PKEY_CTX *ctx); + int EVP_PKEY_encapsulate(EVP_PKEY_CTX *ctx, + unsigned char *out, size_t *outlen, + unsigned char *genkey, size_t *genkeylen); + +=head1 DESCRIPTION + +The EVP_PKEY_encapsulate_init() function initializes a public key algorithm +context I<ctx> for an encapsulation operation. + +The EVP_PKEY_encapsulate() function performs a public key encapsulation +operation using I<ctx> with the name I<name>. +If I<out> is B<NULL> then the maximum size of the output buffer is written to the +I<*outlen> parameter and the maximum size of the generated key buffer is written +to I<*genkeylen>. If I<out> is not B<NULL> and the call is successful then the +internally generated key is written to I<genkey> and its size is written to +I<*genkeylen>. The encapsulated version of the generated key is written to +I<out> and its size is written to I<*outlen>. + +=head1 NOTES + +After the call to EVP_PKEY_encapsulate_init() algorithm specific parameters +for the operation may be set using L<EVP_PKEY_CTX_set_params(3)>. + +=head1 RETURN VALUES + +EVP_PKEY_encapsulate_init() and EVP_PKEY_encapsulate() return 1 for +success and 0 or a negative value for failure. In particular a return value of -2 +indicates the operation is not supported by the public key algorithm. + +=head1 EXAMPLES + +Encapsulate an RSASVE key (for RSA keys). + + #include <openssl/evp.h> + + /* + * NB: assumes rsa_pub_key is an public key of another party. + */ + + EVP_PKEY_CTX *ctx = NULL; + size_t secretlen = 0, outlen = 0; + unsigned char *out = NULL, *secret = NULL; + + ctx = EVP_PKEY_CTX_new_from_pkey(libctx, rsa_pub_key, NULL); + if (ctx = NULL) + /* Error */ + if (EVP_PKEY_encapsulate_init(ctx) <= 0) + /* Error */ + + /* Set the mode - only 'RSASVE' is currently supported */ + if (EVP_PKEY_CTX_set_kem_op(ctx, "RSASVE") <= 0) + /* Error */ + /* Determine buffer length */ + if (EVP_PKEY_encapsulate(ctx, NULL, &outlen, NULL, &secretlen) <= 0) + /* Error */ + + out = OPENSSL_malloc(outlen); + secret = OPENSSL_malloc(secretlen); + if (out == NULL || secret == NULL) + /* malloc failure */ + + /* + * The generated 'secret' can be used as key material. + * The encapsulated 'out' can be sent to another party who can + * decapsulate it using their private key to retrieve the 'secret'. + */ + if (EVP_PKEY_encapsulate(ctx, out, &outlen, secret, &secretlen) <= 0) + /* Error */ + +=head1 SEE ALSO + +L<EVP_PKEY_CTX_new(3)>, +L<EVP_PKEY_decapsulate(3)>, +L<EVP_KEM-RSA(7)>, + +=head1 HISTORY + +These functions were added in OpenSSL 3.0. + +=head1 COPYRIGHT + +Copyright 2020 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 +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut diff --git a/doc/man7/EVP_KEM-RSA.pod b/doc/man7/EVP_KEM-RSA.pod new file mode 100644 index 0000000000..21dc8ad3dd --- /dev/null +++ b/doc/man7/EVP_KEM-RSA.pod @@ -0,0 +1,66 @@ +=pod + +=head1 NAME + +EVP_KEM-RSA +- EVP_KEM RSA keytype and algorithm support + +=head1 DESCRIPTION + +The B<RSA> keytype and its parameters are described in L<EVP_PKEY-RSA(7)>. +See L<EVP_PKEY_encapsulate(3)> and L<EVP_PKEY_decapsulate(3)> for more info. + +=head2 RSA KEM parameters + +=over 4 + +=item "operation" (B<OSSL_KEM_PARAM_OPERATION>) <UTF8 string> + +The OpenSSL RSA Key Encapsulation Mechanism only currently supports the +following operation + +=over 4 + +=item "RSASVE" + +The encapsulate function simply generates a secret using random bytes and then +encrypts the secret using the RSA public key (with no padding). +The decapsulate function recovers the secret using the RSA private key. + +=back + +This can be set using EVP_PKEY_CTX_set_kem_op(). + +=back + + +=head1 CONFORMING TO + +=over 4 + +=item SP800-56Br2 + +Section 7.2.1.2 RSASVE Generate Operation (RSASVE.GENERATE). +Section 7.2.1.3 RSASVE Recovery Operation (RSASVE.RECOVER). + +=back + +=head1 SEE ALSO + +L<EVP_PKEY_CTX_set_kem_op(3)>, +L<EVP_PKEY_encapsulate(3)>, +L<EVP_PKEY_decapsulate(3)> +L<EVP_KEYMGMT(3)>, +L<EVP_PKEY(3)>, +L<provider-keymgmt(7)> + +=head1 COPYRIGHT + +Copyright 2020 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 +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut diff --git a/doc/man7/OSSL_PROVIDER-FIPS.pod b/doc/man7/OSSL_PROVIDER-FIPS.pod index 98c6079d72..b802efe215 100644 --- a/doc/man7/OSSL_PROVIDER-FIPS.pod +++ b/doc/man7/OSSL_PROVIDER-FIPS.pod @@ -136,6 +136,14 @@ This has the property "provider=fips,fips=no" =back +=head2 Asymmetric Key Encapsulation + +=over 4 + +=item RSA, see L<EVP_KEM-RSA(7)> + +=back + =head2 Asymmetric Key Management =over 4 diff --git a/doc/man7/OSSL_PROVIDER-default.pod b/doc/man7/OSSL_PROVIDER-default.pod index a88c0be6e6..848c887b29 100644 --- a/doc/man7/OSSL_PROVIDER-default.pod +++ b/doc/man7/OSSL_PROVIDER-default.pod @@ -182,6 +182,14 @@ The OpenSSL default provider supports these operations and algorithms: =back +=head2 Asymmetric Key Encapsulation + +=over 4 + +=item RSA, see L<EVP_KEM-RSA(7)> + +=back + =head2 Asymmetric Key Management =over 4 diff --git a/doc/man7/provider-kem.pod b/doc/man7/provider-kem.pod new file mode 100644 index 0000000000..4d16a3e625 --- /dev/null +++ b/doc/man7/provider-kem.pod @@ -0,0 +1,207 @@ +=pod + +=head1 NAME + +provider-kem - The kem library E<lt>-E<gt> provider functions + +=head1 SYNOPSIS + +=for openssl multiple includes + + #include <openssl/core_dispatch.h> + #include <openssl/core_names.h> + + /* + * None of these are actual functions, but are displayed like this for + * the function signatures for functions that are offered as function + * pointers in OSSL_DISPATCH arrays. + */ + + /* Context management */ + void *OSSL_FUNC_kem_newctx(void *provctx); + void OSSL_FUNC_kem_freectx(void *ctx); + void *OSSL_FUNC_kem_dupctx(void *ctx); + + /* Encapsulation */ + int OSSL_FUNC_kem_encapsulate_init(void *ctx, void *provkey, const char *name); + int OSSL_FUNC_kem_encapsulate(void *ctx, unsigned char *out, size_t *outlen, + unsigned char *secret, size_t *secretlen); + + /* Decapsulation */ + int OSSL_FUNC_kem_decapsulate_init(void *ctx, void *provkey, const char *name); + int OSSL_FUNC_kem_decapsulate(void *ctx, unsigned char *out, size_t *outlen, + const unsigned char *in, size_t inlen); + + /* KEM parameters */ + int OSSL_FUNC_kem_get_ctx_params(void *ctx, OSSL_PARAM params[]); + const OSSL_PARAM *OSSL_FUNC_kem_gettable_ctx_params(void *provctx); + int OSSL_FUNC_kem_set_ctx_params(void *ctx, const OSSL_PARAM params[]); + const OSSL_PARAM *OSSL_FUNC_kem_settable_ctx_params(void *provctx); + +=head1 DESCRIPTION + +This documentation is primarily aimed at provider authors. See L<provider(7)> +for further information. + +The asymmetric kem (OSSL_OP_KEM) operation enables providers to +implement asymmetric kem algorithms and make them available to applications +via the API functions L<EVP_PKEY_encapsulate(3)>, +L<EVP_PKEY_decapsulate(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 +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_FUNC_{name}>. +For example, the "function" OSSL_FUNC_kem_newctx() has these: + + typedef void *(OSSL_FUNC_kem_newctx_fn)(void *provctx); + static ossl_inline OSSL_FUNC_kem_newctx_fn + OSSL_FUNC_kem_newctx(const OSSL_DISPATCH *opf); + +B<OSSL_DISPATCH> arrays are indexed by numbers that are provided as +macros in L<openssl-core_dispatch.h(7)>, as follows: + + OSSL_FUNC_kem_newctx OSSL_FUNC_KEM_NEWCTX + OSSL_FUNC_kem_freectx OSSL_FUNC_KEM_FREECTX + OSSL_FUNC_kem_dupctx OSSL_FUNC_KEM_DUPCTX + + OSSL_FUNC_kem_encapsulate_init OSSL_FUNC_KEM_ENCAPSULATE_INIT + OSSL_FUNC_kem_encapsulate OSSL_FUNC_KEM_ENCAPSULATE + + OSSL_FUNC_kem_decapsulate_init OSSL_FUNC_KEM_DECAPSULATE_INIT + OSSL_FUNC_kem_decapsulate OSSL_FUNC_KEM_DECAPSULATE + + OSSL_FUNC_kem_get_ctx_params OSSL_FUNC_KEM_GET_CTX_PARAMS + OSSL_FUNC_kem_gettable_ctx_params OSSL_FUNC_KEM_GETTABLE_CTX_PARAMS + OSSL_FUNC_kem_set_ctx_params OSSL_FUNC_KEM_SET_CTX_PARAMS + OSSL_FUNC_kem_settable_ctx_params OSSL_FUNC_KEM_SETTABLE_CTX_PARAMS + +An asymmetric kem algorithm implementation may not implement all of these +functions. +In order to be a consistent set of functions a provider must implement +OSSL_FUNC_kem_newctx and OSSL_FUNC_kem_freectx. +It must also implement both of OSSL_FUNC_kem_encapsulate_init and +OSSL_FUNC_kem_encapsulate, or both of OSSL_FUNC_kem_decapsulate_init and +OSSL_FUNC_kem_decapsulate. +OSSL_FUNC_kem_get_ctx_params is optional but if it is present then so must +OSSL_FUNC_kem_gettable_ctx_params. +Similarly, OSSL_FUNC_kem_set_ctx_params is optional but if it is present then +so must OSSL_FUNC_kem_settable_ctx_params. + +An asymmetric kem algorithm must also implement some mechanism for generating, +loading or importing keys via the key management (OSSL_OP_KEYMGMT) operation. +See L<provider-keymgmt(7)> for further details. + +=head2 Context Management Functions + +OSSL_FUNC_kem_newctx() should create and return a pointer to a provider side +structure for holding context information during an asymmetric kem operation. +A pointer to this context will be passed back in a number of the other +asymmetric kem operation function calls. +The parameter I<provctx> is the provider context generated during provider +initialisation (see L<provider(7)>). + +OSSL_FUNC_kem_freectx() is passed a pointer to the provider side asymmetric +kem context in the I<ctx> parameter. +This function should free any resources associated with that context. + +OSSL_FUNC_kem_dupctx() should duplicate the provider side asymmetric kem +context in the I<ctx> parameter and return the duplicate copy. + +=head2 Asymmetric Key Encapsulation Functions + +OSSL_FUNC_kem_encapsulate_init() initialises a context for an asymmetric +encapsulation given a provider side asymmetric kem context in the I<ctx> +parameter, a pointer to a provider key object in the I<provkey> parameter and +the I<name> of the algorithm. +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)>. + +OSSL_FUNC_kem_encapsulate() performs the actual encapsulation itself. +A previously initialised asymmetric kem context is passed in the I<ctx> +parameter. +Unless I<out> is NULL, the data to be encapsulated is internally generated, +and returned into the the buffer pointed to by the I<secret> parameter and the +encapsulated data should also be written to the location pointed to by the +I<out> parameter. The length of the encapsulated data should be written to +I<*outlen> and the length of the generated secret should be written to +I<*secretlen>. + +If I<out> is NULL then the maximum length of the encapsulated data should be +written to I<*outlen>, and the maximum length of the generated secret should be +written to I<*secretlen>. + +=head2 Decapsulation Functions + +OSSL_FUNC_kem_decapsulate_init() initialises a context for an asymmetric +decapsulation given a provider side asymmetric kem context in the I<ctx> +parameter, a pointer to a provider key object in the I<provkey> parameter, and +a I<name> of the algorithm. +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)>. + +OSSL_FUNC_kem_decapsulate() performs the actual decapsulation itself. +A previously initialised asymmetric kem context is passed in the I<ctx> +parameter. +The data to be decapsulated is pointed to by the I<in> parameter which is I<inlen> +bytes long. +Unless I<out> is NULL, the decapsulated data should be written to the location +pointed to by the I<out> parameter. +The length of the decapsulated data should be written to I<*outlen>. +If I<out> is NULL then the maximum length of the decapsulated data should be +written to I<*outlen>. + +=head2 Asymmetric Key Encapsulation Parameters + +See L<OSSL_PARAM(3)> for further details on the parameters structure used by +the OSSL_FUNC_kem_get_ctx_params() and OSSL_FUNC_kem_set_ctx_params() +functions. + +OSSL_FUNC_kem_get_ctx_params() gets asymmetric kem parameters associated +with the given provider side asymmetric kem context I<ctx> and stores them in +I<params>. +OSSL_FUNC_kem_set_ctx_params() sets the asymmetric kem parameters associated +with the given provider side asymmetric kem context I<ctx> to I<params>. +Any parameter settings are additional to any that were previously set. + +No parameters are currently recognised by built-in asymmetric kem algorithms. + +OSSL_FUNC_kem_gettable_ctx_params() and OSSL_FUNC_kem_settable_ctx_params() +get a constant B<OSSL_PARAM> array that describes the gettable and settable +parameters, i.e. parameters that can be used with OSSL_FUNC_kem_get_ctx_params() +and OSSL_FUNC_kem_set_ctx_params() respectively. +See L<OSSL_PARAM(3)> for the use of B<OSSL_PARAM> as parameter descriptor. + +=head1 RETURN VALUES + +OSSL_FUNC_kem_newctx() and OSSL_FUNC_kem_dupctx() should return the newly +created provider side asymmetric kem context, or NULL on failure. + +All other functions should return 1 for success or 0 on error. + +=head1 SEE ALSO + +L<provider(7)> + +=head1 HISTORY + +The provider KEM interface was introduced in OpenSSL 3.0. + +=head1 COPYRIGHT + +Copyright 2020 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 +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut diff --git a/doc/man7/provider.pod b/doc/man7/provider.pod index 2f7f019650..ead37b5769 100644 --- a/doc/man7/provider.pod +++ b/doc/man7/provider.pod @@ -154,6 +154,12 @@ The number for this operation is B<OSSL_OP_ASYM_CIPHER>. The functions the provider can offer are described in L<provider-asym_cipher(7)> +=item Asymmetric Key Encapsulation + +In the OpenSSL libraries, the corresponding method object is B<EVP_KEM>. +The number for this operation is B<OSSL_OP_KEM>. +The functions the provider can offer are described in L<provider-kem(7)> + =item Encoding In the OpenSSL libraries, the corresponding method object is |