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OpenSSL_add_all_algorithms(3)
NAME
  OpenSSL_add_all_algorithms, OpenSSL_add_all_ciphers,
  OpenSSL_add_all_digests - Add algorithms to internal table

SYNOPSIS
  #include <openssl/evp.h>

  void OpenSSL_add_all_algorithms(
	  void );

  void OpenSSL_add_all_ciphers(
	  void );

  void OpenSSL_add_all_digests(
	  void );

  void EVP_cleanup(
	  void );

DESCRIPTION
  OpenSSL keeps an internal table of digest algorithms and ciphers. It uses
  this table to lookup ciphers via functions such as EVP_get_cipher_byname().

  The OpenSSL_add_all_digests() function adds all digest algorithms to the
  table.

  The OpenSSL_add_all_algorithms() function adds all algorithms to the table
  (digests and ciphers).

  The OpenSSL_add_all_ciphers() function adds all encryption algorithms to
  the table including password based encryption algorithms.

  The EVP_cleanup() function removes all ciphers and digests from the table.

NOTES
  A typical application will call the OpenSSL_add_all_algorithms() function
  initially and the EVP_cleanup() function before exiting.

  An application does not need to add algorithms to use them explicitly, for
  example by EVP_sha1(). It needs to add them if it (or any of the functions
  it calls) needs to lookup algorithms.

  The cipher and digest lookup functions are used in many parts of the
  library. If the table is not initialized several functions will not work
  correctly and complain they cannot find algorithms. This includes the PEM,
  PKCS#12, SSL and S/MIME libraries. This is a common query in the OpenSSL
  mailing lists.

  Calling the OpenSSL_add_all_algorithms() function links all algorithms. As
  a result, a statically linked executable can be quite large. If this is
  important, it is possible to add only the required ciphers and digests.

RESTRICTIONS
  Although the functions do not return error codes it is possible for them to
  fail. This will only happen as a result of a memory allocation failure, so
  it is not much of a problem in practice.

RETURN VALUES
  None of the functions return a value.

SEE ALSO
  Functions: evp(3), EVP_DigestInit(3), EVP_EncryptInit(3)

Index for Section 3

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