Provided by: openssl_3.4.1-1ubuntu3_amd64 bug

NAME
       EVP_KEM-EC - EVP_KEM EC keytype and algorithm support


DESCRIPTION
       The EC keytype and its parameters are described in EVP_PKEY-EC(7).  See EVP_PKEY_encapsulate(3) and
       EVP_PKEY_decapsulate(3) for more info.

   EC KEM parameters
       "operation" (OSSL_KEM_PARAM_OPERATION)<UTF8 string>
           The OpenSSL EC Key Encapsulation Mechanisms only supports the following operation:

           "DHKEM" (OSSL_KEM_PARAM_OPERATION_DHKEM)
               The encapsulate function generates an ephemeral keypair. It produces keymaterial by doing an ECDH
               key  exchange  using  the  ephemeral  private  key  and  a  supplied recipient public key. A HKDF
               operation using the keymaterial and a kem context then  produces  a  shared  secret.  The  shared
               secret  and  the  ephemeral public key are returned.  The decapsulate function uses the recipient
               private key and the ephemeral public key to produce the same keymaterial, which can then be  used
               to           produce           the           same           shared          secret.           See
               <https://www.rfc-editor.org/rfc/rfc9180.html#name-dh-based-kem-dhkem>

           This can be set using either EVP_PKEY_CTX_set_kem_op() or EVP_PKEY_CTX_set_params().

       "ikme" (OSSL_KEM_PARAM_IKME) <octet string>
           Used to specify the key material used for generation of the ephemeral key.  This value should not  be
           reused  for  other  purposes.   It  can  only be used for the curves "P-256", "P-384" and "P-521" and
           should have a length of at least the size of the encoded private key (i.e. 32,  48  and  66  for  the
           listed curves).  If this value is not set, then a random ikm is used.


CONFORMING TO
       RFC9180


SEE ALSO
       EVP_PKEY_CTX_set_kem_op(3), EVP_PKEY_encapsulate(3), EVP_PKEY_decapsulate(3) EVP_KEYMGMT(3), EVP_PKEY(3),
       provider-keymgmt(7)


HISTORY
       This functionality was added in OpenSSL 3.2.


COPYRIGHT
       Copyright 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  in  the  file  LICENSE  in  the  source  distribution  or  at
       <https://www.openssl.org/source/license.html>.

3.4.1                                              2025-04-03                                   EVP_KEM-EC(7SSL)