Provided by: openssl_3.0.5-2ubuntu1_amd64 bug

NAME

       life_cycle-pkey - The PKEY algorithm life-cycle

DESCRIPTION

       All public keys (PKEYs) go through a number of stages in their life-cycle:

       start
           This state represents the PKEY before it has been allocated.  It is the starting state
           for any life-cycle transitions.

       newed
           This state represents the PKEY after it has been allocated.

       decapsulate
           This state represents the PKEY when it is ready to perform a private key decapsulation
           opeartion.

       decrypt
           This state represents the PKEY when it is ready to decrypt some ciphertext.

       derive
           This state represents the PKEY when it is ready to derive a shared secret.

       digest sign
           This state represents the PKEY when it is ready to perform a private key signature
           operation.

       encapsulate
           This state represents the PKEY when it is ready to perform a public key encapsulation
           opeartion.

       encrypt
           This state represents the PKEY when it is ready to encrypt some plaintext.

       key generation
           This state represents the PKEY when it is ready to generate a new public/private key.

       parameter generation
           This state represents the PKEY when it is ready to generate key parameters.

       verify
           This state represents the PKEY when it is ready to verify a public key signature.

       verify recover
           This state represents the PKEY when it is ready to recover a public key signature
           data.

       freed
           This state is entered when the PKEY is freed.  It is the terminal state for all life-
           cycle transitions.

   State Transition Diagram
       The usual life-cycle of a PKEY object is illustrated:
                                                          +-------------+
                                                          |             |
                                                          |    start    |
                                                          |             |
                          EVP_PKEY_derive                 +-------------+
        +-------------+   EVP_PKEY_derive_set_peer               |
       +-------------+
        |             |----------------------------+             |
       +----------------------------|             |
        |   derive    |                            |             |             |  EVP_PKEY_verify
       |   verify    |
        |             |<---------------------------+             |
       +--------------------------->|             |
        +-------------+                                          |
       +-------------+
                    ^                                            |
       ^
                    |   EVP_PKEY_derive_init                     |
       EVP_PKEY_verify_init           |
                    +---------------------------------------+    |
       +---------------------------------------+
                                                            |    |    |
        +-------------+                                     |    |    |
       +-------------+
        |             |----------------------------+        |    |    |
       +----------------------------|             |
        | digest sign |   EVP_PKEY_sign            |        |    |    |        |
       EVP_PKEY_verify_recover   |   verify    |
        |             |<---------------------------+        |    |    |
       +--------------------------->|   recover   |
        +-------------+                                     |    |    |
       +-------------+
                    ^                                       |    |    |
       ^
                    |     EVP_PKEY_sign_init                |    |    |
       EVP_PKEY_verify_recover_init   |
                    +---------------------------------+     |    |    |
       +---------------------------------+
                                                      |     |    |    |     |
        +-------------+                               |     |    |    |     |
       +-------------+
        |             |----------------------------+  |     |    |    |     |
       +----------------------------|             |
        | decapsulate |   EVP_PKEY_decapsulate     |  |     |    |    |     |  |
       EVP_PKEY_decrypt          |   decrypt   |
        |             |<---------------------------+  |     |    v    |     |
       +--------------------------->|             |
        +-------------+                               |   +-------------+   |
       +-------------+
                    ^                                 +---|             |---+
       ^
                    |     EVP_PKEY_decapsulate_init       |             |
       EVP_PKEY_decrypt_init          |
                    +-------------------------------------|    newed
       |-------------------------------------+
                                                          |             |
                                                      +---|             |---+
        +-------------+                               |   +-------------+   |
       +-------------+
        |             |----------------------------+  |     |         |     |
       +----------------------------|             |
        | encapsulate |   EVP_PKEY_encapsulate     |  |     |         |     |  |
       EVP_PKEY_encrypt          |   encrypt   |
        |             |<---------------------------+  |     |         |     |
       +--------------------------->|             |
        +-------------+                               |     |         |     |
       +-------------+
                    ^                                 |     |         |     |
       ^
                    |     EVP_PKEY_encapsulate_init   |     |         |     |
       EVP_PKEY_encrypt_init          |
                    +---------------------------------+     |         |
       +---------------------------------+
                                                            |         |
                    +---------------------------------------+
       +---------------------------------------+
                    |     EVP_PKEY_paramgen_init
       EVP_PKEY_keygen_init           |
                    v
       v
        +-------------+
       +-------------+
        |             |----------------------------+
       +----------------------------|             |
        |  parameter  |                            |                           |
       |     key     |
        |  generation |<---------------------------+
       +--------------------------->|  generation |
        +-------------+   EVP_PKEY_paramgen                                       EVP_PKEY_keygen
       +-------------+
                          EVP_PKEY_gen                                            EVP_PKEY_gen

                                           + - - - - - +                    +-----------+
                                           '           ' EVP_PKEY_CTX_free  |           |
                                           ' any state '------------------->|   freed   |
                                           '           '                    |           |
                                           + - - - - - +                    +-----------+

   Formal State Transitions
       This section defines all of the legal state transitions.  This is the canonical list.
        Function Call
       ---------------------------------------------------------------------- Current State
       ----------------------------------------------------------------------
                                      start    newed       digest       verify       verify
       encrypt      decrypt      derive      encapsulate  decapsulate  parameter       key
       freed
                                                            sign                     recover
       generation   generation
        EVP_PKEY_CTX_new              newed
        EVP_PKEY_CTX_new_id           newed
        EVP_PKEY_CTX_new_from_name    newed
        EVP_PKEY_CTX_new_from_pkey    newed
        EVP_PKEY_sign_init                    digest       digest       digest       digest
       digest       digest       digest       digest       digest       digest       digest
                                               sign         sign         sign         sign
       sign         sign         sign         sign         sign         sign         sign
        EVP_PKEY_sign                                      digest
                                                            sign
        EVP_PKEY_verify_init                  verify       verify       verify       verify
       verify       verify       verify       verify       verify       verify       verify
        EVP_PKEY_verify                                                 verify
        EVP_PKEY_verify_recover_init          verify       verify       verify       verify
       verify       verify       verify       verify       verify       verify       verify
                                              recover      recover      recover      recover
       recover      recover      recover      recover      recover      recover      recover
        EVP_PKEY_verify_recover                                                      verify
                                                                                     recover
        EVP_PKEY_encrypt_init                 encrypt      encrypt      encrypt      encrypt
       encrypt      encrypt      encrypt      encrypt      encrypt      encrypt      encrypt
        EVP_PKEY_encrypt
       encrypt
        EVP_PKEY_decrypt_init                 decrypt      decrypt      decrypt      decrypt
       decrypt      decrypt      decrypt      decrypt      decrypt      decrypt      decrypt
        EVP_PKEY_decrypt
       decrypt
        EVP_PKEY_derive_init                  derive       derive       derive       derive
       derive       derive       derive       derive       derive       derive       derive
        EVP_PKEY_derive_set_peer
       derive
        EVP_PKEY_derive
       derive
        EVP_PKEY_encapsulate_init            encapsulate  encapsulate  encapsulate  encapsulate
       encapsulate  encapsulate  encapsulate  encapsulate  encapsulate  encapsulate  encapsulate
        EVP_PKEY_encapsulate
       encapsulate
        EVP_PKEY_decapsulate_init            decapsulate  decapsulate  decapsulate  decapsulate
       decapsulate  decapsulate  decapsulate  decapsulate  decapsulate  decapsulate  decapsulate
        EVP_PKEY_decapsulate
       decapsulate
        EVP_PKEY_paramgen_init               parameter    parameter    parameter    parameter
       parameter    parameter    parameter    parameter    parameter    parameter    parameter
                                             generation   generation   generation   generation
       generation   generation   generation   generation   generation   generation   generation
        EVP_PKEY_paramgen
       parameter
                                                                                                                                                                  generation
        EVP_PKEY_keygen_init                    key          key          key          key
       key          key          key          key          key          key          key
                                             generation   generation   generation   generation
       generation   generation   generation   generation   generation   generation   generation
        EVP_PKEY_keygen
       key
                                                                                                                                                                               generation
        EVP_PKEY_gen
       parameter       key
                                                                                                                                                                  generation
       generation
        EVP_PKEY_CTX_get_params                newed       digest       verify       verify
       encrypt      decrypt      derive      encapsulate  decapsulate  parameter       key
                                                            sign                     recover
       generation   generation
        EVP_PKEY_CTX_set_params                newed       digest       verify       verify
       encrypt      decrypt      derive      encapsulate  decapsulate  parameter       key
                                                            sign                     recover
       generation   generation
        EVP_PKEY_CTX_gettable_params           newed       digest       verify       verify
       encrypt      decrypt      derive      encapsulate  decapsulate  parameter       key
                                                            sign                     recover
       generation   generation
        EVP_PKEY_CTX_settable_params           newed       digest       verify       verify
       encrypt      decrypt      derive      encapsulate  decapsulate  parameter       key
                                                            sign                     recover
       generation   generation
        EVP_PKEY_CTX_free             freed    freed        freed        freed        freed
       freed        freed        freed        freed        freed        freed        freed

NOTES

       At some point the EVP layer will begin enforcing the transitions described herein.

SEE ALSO

       EVP_PKEY_new(3), EVP_PKEY_decapsulate(3), EVP_PKEY_decrypt(3), EVP_PKEY_encapsulate(3),
       EVP_PKEY_encrypt(3), EVP_PKEY_derive(3), EVP_PKEY_keygen(3), EVP_PKEY_sign(3),
       EVP_PKEY_verify(3), EVP_PKEY_verify_recover(3)

HISTORY

       The provider PKEY interface was introduced in OpenSSL 3.0.

COPYRIGHT

       Copyright 2021 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>.