diff options
author | Shane Lontis <shane.lontis@oracle.com> | 2020-11-16 12:42:18 +1000 |
---|---|---|
committer | Shane Lontis <shane.lontis@oracle.com> | 2020-12-02 12:15:05 +1000 |
commit | 89cccbea51fa52a1e4784a9ece35d96e4dcbfd30 (patch) | |
tree | 89cb59183ed18f1e5dd5cb86fed810b04cce466e /doc/man7/EVP_KDF-X942-ASN1.pod | |
parent | 8018352457cf9c98ce59f1e591fcd69f2153b649 (diff) |
Add EVP_KDF-X942 to the fips module
The X942 KDF had been modified so that it supports all optional fields - not
just the fields used by CMS.
As there are 2 types of KDF for X942 - this has been made a bit clearer
by adding an X942KDF-ASN1 alias. X942KDF-CONCAT has also been added as an
alias of X963KDF.
This work was instigated as a result of the ACVP tests optionally being
able to use keybits for the supp_pubinfo field.
Setting the parameter OSSL_KDF_PARAM_X942_USE_KEYBITS to 0 allows this
to be disabled.
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/13418)
Diffstat (limited to 'doc/man7/EVP_KDF-X942-ASN1.pod')
-rw-r--r-- | doc/man7/EVP_KDF-X942-ASN1.pod | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/doc/man7/EVP_KDF-X942-ASN1.pod b/doc/man7/EVP_KDF-X942-ASN1.pod new file mode 100644 index 0000000000..3c5c3077ca --- /dev/null +++ b/doc/man7/EVP_KDF-X942-ASN1.pod @@ -0,0 +1,146 @@ +=pod + +=head1 NAME + +EVP_KDF-X942-ASN1 - The X9.42-2003 asn1 EVP_KDF implementation + +=head1 DESCRIPTION + +The EVP_KDF-X942-ASN1 algorithm implements the key derivation function +X942KDF-ASN1. It is used by DH KeyAgreement, to derive a key using input such as +a shared secret key and other info. The other info is DER encoded data that +contains a 32 bit counter as well as optional fields for "partyu-info", +"partyv-info", "supp-pubinfo" and "supp-privinfo". +This kdf is used by Cryptographic Message Syntax (CMS). + +=head2 Identity + +"X942KDF-ASN1" or "X942KDF" is the name for this implementation; it +can be used with the EVP_KDF_fetch() function. + +=head2 Supported parameters + +The supported parameters are: + +=over 4 + +=item "properties" (B<OSSL_KDF_PARAM_PROPERTIES>) <UTF8 string> + +=item "digest" (B<OSSL_KDF_PARAM_DIGEST>) <UTF8 string> + +These parameters work as described in L<EVP_KDF(3)/PARAMETERS>. + +=item "key" (B<OSSL_KDF_PARAM_KEY>) <octet string> + +The shared secret used for key derivation. This parameter sets the secret. + +=item "partyu-info" (B<OSSL_KDF_PARAM_X942_PARTYUINFO>) <octet string> + +An optional octet string containing public info contributed by the initiator. + +=item "ukm" (B<OSSL_KDF_PARAM_UKM>) <octet string> + +An alias for "partyu-info". +In CMS this is the user keying material. + +=item "partyv-info" (B<OSSL_KDF_PARAM_X942_PARTYVINFO>) <octet string> + +An optional octet string containing public info contributed by the responder. + +=item "supp-pubinfo" (B<OSSL_KDF_PARAM_X942_SUPP_PUBINFO>) <octet string> + +An optional octet string containing some additional, mutually-known public +information. Setting this value also sets "use-keybits" to 0. + +=item "use-keybits" (B<OSSL_KDF_PARAM_X942_SUPP_PRIVINFO>) <integer> + +The default value of 1 will use the KEK key length (in bits) as the +"supp-pubinfo". A value of 0 disables setting the "supp-pubinfo". + +=item "supp-privinfo" (B<OSSL_KDF_PARAM_X942_SUPP_PRIVINFO>) <octet string> + +An optional octet string containing some additional, mutually-known private +information. + +=item "cekalg" (B<OSSL_KDF_PARAM_CEK_ALG>) <UTF8 string> + +This parameter sets the CEK wrapping algorithm name. +Valid values are "AES-128-WRAP", "AES-192-WRAP", "AES-256-WRAP" and "DES3-WRAP". + +=back + +=head1 NOTES + +A context for X942KDF can be obtained by calling: + + EVP_KDF *kdf = EVP_KDF_fetch(NULL, "X942KDF", NULL); + EVP_KDF_CTX *kctx = EVP_KDF_CTX_new(kdf); + +The output length of an X942KDF is specified via the I<keylen> +parameter to the L<EVP_KDF_derive(3)> function. + +=head1 EXAMPLES + +This example derives 24 bytes, with the secret key "secret" and random user +keying material: + + EVP_KDF_CTX *kctx; + EVP_KDF_CTX *kctx; + unsigned char out[192/8]; + unsignred char ukm[64]; + OSSL_PARAM params[5], *p = params; + + if (RAND_bytes(ukm, sizeof(ukm)) <= 0) + error("RAND_bytes"); + + kdf = EVP_KDF_fetch(NULL, "X942KDF", NULL); + if (kctx == NULL) + error("EVP_KDF_fetch"); + kctx = EVP_KDF_CTX_new(kdf); + EVP_KDF_free(kdf); + if (kctx == NULL) + error("EVP_KDF_CTX_new"); + + *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, "SHA256", 0); + *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SECRET, + "secret", (size_t)6); + *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_UKM, ukm, sizeof(ukm)); + *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_CEK_ALG, "AES-256-WRAP, 0); + *p = OSSL_PARAM_construct_end(); + if (EVP_KDF_CTX_set_params(kctx, params) <= 0) + error("EVP_KDF_CTX_set_params"); + + if (EVP_KDF_derive(kctx, out, sizeof(out)) <= 0) + error("EVP_KDF_derive"); + + EVP_KDF_CTX_free(kctx); + +=head1 CONFORMING TO + +ANS1 X9.42-2003 +RFC 2631 + +=head1 SEE ALSO + +L<EVP_KDF(3)>, +L<EVP_KDF_CTX_new(3)>, +L<EVP_KDF_CTX_free(3)>, +L<EVP_KDF_CTX_set_params(3)>, +L<EVP_KDF_CTX_get_kdf_size(3)>, +L<EVP_KDF_derive(3)>, +L<EVP_KDF(3)/PARAMETERS> + +=head1 HISTORY + +This functionality was added to OpenSSL 3.0. + +=head1 COPYRIGHT + +Copyright 2019-2020 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 |