---
name: "life_cycle-mac"
section: "7ssl"
platform: "linux"
package: "openssl"
version: "3.6.5-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/life_cycle-mac"
---

# life\_cycle-mac(7ssl)

The MAC algorithm life-cycle

## NAME

life\_cycle-mac - The MAC algorithm life-cycle

## DESCRIPTION

All message authentication codes (MACs) go through a number of stages in their life-cycle:

- start

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

- newed

  This state represents the MAC after it has been allocated.

- initialised

  This state represents the MAC when it is set up and capable of processing input.

- updated

  This state represents the MAC when it is set up and capable of processing additional input or generating output.

- finaled

  This state represents the MAC when it has generated output.

- freed

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

### State Transition Diagram

The usual life-cycle of a MAC is illustrated:\
                  \+-------------------+\
                  \|       start       \|\
                  \+-------------------+\
                    \|\
                    \| EVP\_MAC\_CTX\_new\
                    v\
                  \+-------------------+\
                  \|       newed       \|\
                  \+-------------------+\
                    \|\
                    \| EVP\_MAC\_init\
                    v\
                  \+-------------------+\
               \+\> \|    initialised    \| \<+\
               \|  +-------------------+  \|\
               \|    \|                    \|\
               \|    \| EVP\_MAC\_update     \| EVP\_MAC\_init\
               \|    v                    \|\
  EVP\_MAC\_init \|  +-------------------+  \|\
               \|  \|      updated      \| -+\
               \|  +-------------------+\
               \|    \|               \|\
               \|    \| EVP\_MAC\_final \| EVP\_MAC\_finalXOF\
               \|    v               v\
               \|  +-------------------+\
               \+- \|      finaled      \|\
                  \+-------------------+\
                    \|\
                    \| EVP\_MAC\_CTX\_free\
                    v\
                  \+-------------------+\
                  \|       freed       \|\
                  \+-------------------+

### Formal State Transitions

This section defines all of the legal state transitions. This is the canonical list.\
  Function Call                   --------------------- Current State ----------------------\
                                  start   newed    initialised   updated     finaled   freed\
  EVP\_MAC\_CTX\_new                 newed\
  EVP\_MAC\_init                         initialised initialised initialised initialised\
  EVP\_MAC\_update                                     updated     updated\
  EVP\_MAC\_final                                                  finaled\
  EVP\_MAC\_finalXOF                                               finaled\
  EVP\_MAC\_CTX\_free                freed   freed       freed       freed       freed\
  EVP\_MAC\_CTX\_get\_params                  newed    initialised   updated\
  EVP\_MAC\_CTX\_set\_params                  newed    initialised   updated\
  EVP\_MAC\_CTX\_gettable\_params             newed    initialised   updated\
  EVP\_MAC\_CTX\_settable\_params             newed    initialised   updated

## NOTES

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

## SEE ALSO

**provider-mac**(7), **EVP\_MAC**(3).

## HISTORY

The provider MAC 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\>.