From ce82b892e8b86d68d02096554b4e07af7f095368 Mon Sep 17 00:00:00 2001 From: Nicola Tuveri Date: Sun, 9 Feb 2020 13:56:27 +0200 Subject: [PATCH] [PROV][EC] Update documentation Reviewed-by: Matt Caswell Reviewed-by: Richard Levitte Reviewed-by: Shane Lontis (Merged from https://github.com/openssl/openssl/pull/10631) --- doc/man7/provider-keyexch.pod | 98 ++++++++++++++++++++++++++++++----- doc/man7/provider-keymgmt.pod | 67 +++++++++++++++++++++--- 2 files changed, 145 insertions(+), 20 deletions(-) diff --git a/doc/man7/provider-keyexch.pod b/doc/man7/provider-keyexch.pod index ceb03ec2f0..3fde04869d 100644 --- a/doc/man7/provider-keyexch.pod +++ b/doc/man7/provider-keyexch.pod @@ -31,6 +31,8 @@ provider-keyexch - The keyexch library E-E provider functions /* 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 OP_keyexch_get_ctx_params(void *ctx, OSSL_PARAM params[]); + const OSSL_PARAM *OP_keyexch_gettable_ctx_params(void); =head1 DESCRIPTION @@ -71,6 +73,8 @@ macros in L, as follows: OP_keyexch_set_ctx_params OSSL_FUNC_KEYEXCH_SET_CTX_PARAMS OP_keyexch_settable_ctx_params OSSL_FUNC_KEYEXCH_SETTABLE_CTX_PARAMS + OP_keyexch_get_ctx_params OSSL_FUNC_KEYEXCH_GET_CTX_PARAMS + OP_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 @@ -123,15 +127,36 @@ The length of the shared secret should be written to I<*secretlen>. If I is NULL then the maximum length of the shared secret should be written to I<*secretlen>. -=head2 Key Exchange Parameters - -See L for further details on the parameters structure used by -the OP_keyexch_set_params() function. +=head2 Key Exchange Parameters Functions OP_keyexch_set_ctx_params() sets key exchange parameters associated with the -given provider side key exchange context I to I. +given provider side key exchange context I to I, +see L. Any parameter settings are additional to any that were previously set. +OP_keyexch_get_ctx_params() gets key exchange parameters associated with the +given provider side key exchange context I into I, +see L. + +OP_keyexch_settable_ctx_params() yields a constant B array that +describes the settable parameters, i.e. parameters that can be used with +OP_signature_set_ctx_params(). +If OP_keyexch_settable_ctx_params() is present, OP_keyexch_set_ctx_params() must +also be present, and vice versa. +Similarly, OP_keyexch_gettable_ctx_params() yields a constant B +array that describes the gettable parameters, i.e. parameters that can be +handled by OP_signature_get_ctx_params(). +If OP_keyexch_gettable_ctx_params() is present, OP_keyexch_get_ctx_params() must +also be present, and vice versa. +See L for the use of B as parameter descriptor. + +Notice that not all settable parameters are also gettable, and vice versa. + +=head2 Key Exchange Parameters + +See L for further details on the parameters structure used by +the OP_keyexch_set_ctx_params() and OP_keyexch_get_ctx_params() functions. + 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 @@ -150,20 +175,69 @@ 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. -=back +=item "ecdh-cofactor-mode" (B) -OP_keyexch_settable_ctx_params() gets a constant B array that -describes the settable parameters, i.e. parameters that can be used with -OP_signature_set_ctx_params(). -See L for the use of B as parameter descriptor. +Sets/gets the ECDH mode of operation for the associated key exchange ctx. + +In the context of an Elliptic Curve Diffie-Hellman key exchange, this parameter +can be used to select between the plain Diffie-Hellman (DH) or Cofactor +Diffie-Hellman (CDH) variants of the key exchange algorithm. + +When setting, the value should be 1, 0 or -1, respectively forcing cofactor mode +on, off, or resetting it to the default for the private key associated with the +given key exchange ctx. + +When getting, the value should be either 1 or 0, respectively signaling if the +cofactor mode is on or off. + +See also L for the related +B parameter that can be set on a +per-key basis. + +=item "kdf-type" (B) + +Sets/gets the Key Derivation Function type to apply within the associated key +exchange ctx. + +=item "kdf-digest" (B) + +Sets/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) + +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) + +Sets/gets the desired size for the output of the chosen Key Derivation Function +associated with the given key exchange ctx. + +=item "kdf-ukm" (B) + +Sets/gets User Key Material to be used as part of the selected Key Derivation +Function associated with the given key exchange ctx. + +=item "kdf-ukm-len" (B) + +Sets/gets the size of the User Key Material to be used as part of the selected +Key Derivation Function associated with the given key exchange ctx. + +=back =head1 RETURN VALUES OP_keyexch_newctx() and OP_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. +OP_keyexch_init(), OP_keyexch_set_peer(), OP_keyexch_derive(), +OP_keyexch_set_params(), and OP_keyexch_get_params() should return 1 for success +or 0 on error. + +OP_keyexch_settable_ctx_params() and OP_keyexch_gettable_ctx_params() should +always return a constant B array. =head1 SEE ALSO diff --git a/doc/man7/provider-keymgmt.pod b/doc/man7/provider-keymgmt.pod index e9e4de5622..279256d567 100644 --- a/doc/man7/provider-keymgmt.pod +++ b/doc/man7/provider-keymgmt.pod @@ -21,6 +21,8 @@ provider-keymgmt - The KEYMGMT library E-E provider functions /* Key object information */ int OP_keymgmt_get_params(void *keydata, OSSL_PARAM params[]); const OSSL_PARAM *OP_keymgmt_gettable_params(void); + int OP_keymgmt_set_params(void *keydata, const OSSL_PARAM params[]); + const OSSL_PARAM *OP_keymgmt_settable_params(void); /* Key object content checks */ int OP_keymgmt_has(void *keydata, int selection); @@ -30,7 +32,7 @@ provider-keymgmt - The KEYMGMT library E-E provider functions /* Key object import and export functions */ int OP_keymgmt_import(int selection, void *keydata, const OSSL_PARAM params[]); - const OSSL_PARAM *OP_keymgmt_import_types, (int selection); + const OSSL_PARAM *OP_keymgmt_import_types(int selection); int OP_keymgmt_export(int selection, void *keydata, OSSL_CALLBACK *param_cb, void *cbarg); const OSSL_PARAM *OP_keymgmt_export_types(int selection); @@ -38,9 +40,6 @@ provider-keymgmt - The KEYMGMT library E-E provider functions /* Key object validation */ int OP_keymgmt_validate(void *keydata, int selection); - /* Discovery of supported operations */ - const char *OP_keymgmt_query_operation_name(int operation_id); - =head1 DESCRIPTION The KEYMGMT operation doesn't have much public visibility in OpenSSL @@ -78,6 +77,8 @@ macros in L, as follows: OP_keymgmt_get_params OSSL_FUNC_KEYMGMT_GET_PARAMS OP_keymgmt_gettable_params OSSL_FUNC_KEYMGMT_GETTABLE_PARAMS + OP_keymgmt_set_params OSSL_FUNC_KEYMGMT_SET_PARAMS + OP_keymgmt_settable_params OSSL_FUNC_KEYMGMT_SETTABLE_PARAMS OP_keymgmt_query_operation_name OSSL_FUNC_KEYMGMT_QUERY_OPERATION_NAME @@ -202,7 +203,17 @@ descriptor B, for parameters that OP_keymgmt_get_params() can handle. If OP_keymgmt_gettable_params() is present, OP_keymgmt_get_params() -must also be present. +must also be present, and vice versa. + +OP_keymgmt_set_params() should update information data associated +with the given I, see L. + +OP_keymgmt_settable_params() should return a constant array of +descriptor B, for parameters that OP_keymgmt_set_params() +can handle. + +If OP_keymgmt_settable_params() is present, OP_keymgmt_set_params() +must also be present, and vice versa. =head2 Key Object Checking Functions @@ -214,7 +225,7 @@ returns NULL, the caller is free to assume that there's an algorithm from the same provider, of the same name as the one used to fetch the keymgmt and try to use that. -OP_keymgmt_has() should check whether the given I the subsets +OP_keymgmt_has() should check whether the given I contains the subsets of data indicated by the I. A combination of several selector bits must consider all those subsets, not just one. An implementation is, however, free to consider an empty subset of data @@ -249,8 +260,10 @@ OP_keymgmt_export() callback can expect to receive. See L for further details on the parameters structure. -Parameters currently recognised by built-in keymgmt algorithms' -OP_keymgmt_get_params: +Parameters currently recognised by built-in keymgmt algorithms +are as follows. +Not all parameters are relevant to, or are understood by all keymgmt +algorithms: =over 4 @@ -278,8 +291,46 @@ dimensions handled in the rest of the same provider. The value should be the number of security bits of the given key. Bits of security is defined in SP800-57. +=item "use-cofactor-flag" (B, +B) + +The value should be either 1 or 0, to respectively enable or disable +use of the cofactor in operations using this key. + +In the context of a key that can be used to perform an Elliptic Curve +Diffie-Hellman key exchange, this parameter can be used to mark a requirement +for using the Cofactor Diffie-Hellman (CDH) variant of the key exchange +algorithm. + +See also L for the related +B parameter that can be set on a +per-operation basis. + =back +=head1 RETURN VALUES + +OP_keymgmt_new() should return a valid reference to the newly created provider +side key object, or NULL on failure. + +OP_keymgmt_import(), OP_keymgmt_export(), OP_keymgmt_get_params() and +OP_keymgmt_set_params() should return 1 for success or 0 on error. + +OP_keymgmt_validate() should return 1 on successful validation, or 0 on +failure. + +OP_keymgmt_has() should return 1 if all the selected data subsets are contained +in the given I or 0 otherwise. + +OP_keymgmt_query_operation_name() should return a pointer to a string matching +the requested operation, or NULL if the same name used to fetch the keymgmt +applies. + +OP_keymgmt_gettable_params() and OP_keymgmt_settable_params() +OP_keymgmt_import_types(), OP_keymgmt_export_types() +should +always return a constant B array. + =head1 SEE ALSO L -- 2.25.1