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+=pod
+
+=head1 NAME
+
+SSL_COMP_add_compression_method, SSL_COMP_get_compression_methods,
+SSL_COMP_get0_name, SSL_COMP_get_id, SSL_COMP_free_compression_methods
+- handle SSL/TLS integrated compression methods
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm);
+ STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void);
+ const char *SSL_COMP_get0_name(const SSL_COMP *comp);
+ int SSL_COMP_get_id(const SSL_COMP *comp);
+
+Deprecated:
+
+ #if OPENSSL_API_COMPAT < 0x10100000L
+ void SSL_COMP_free_compression_methods(void)
+ #endif
+
+=head1 DESCRIPTION
+
+SSL_COMP_add_compression_method() adds the compression method B<cm> with
+the identifier B<id> to the list of available compression methods. This
+list is globally maintained for all SSL operations within this application.
+It cannot be set for specific SSL_CTX or SSL objects.
+
+SSL_COMP_get_compression_methods() returns a stack of all of the available
+compression methods or NULL on error.
+
+SSL_COMP_get0_name() returns the name of the compression method B<comp>.
+
+SSL_COMP_get_id() returns the id of the compression method B<comp>.
+
+SSL_COMP_free_compression_methods() releases any resources acquired to
+maintain the internal table of compression methods.
+
+=head1 NOTES
+
+The TLS standard (or SSLv3) allows the integration of compression methods
+into the communication. The TLS RFC does however not specify compression
+methods or their corresponding identifiers, so there is currently no compatible
+way to integrate compression with unknown peers. It is therefore currently not
+recommended to integrate compression into applications. Applications for
+non-public use may agree on certain compression methods. Using different
+compression methods with the same identifier will lead to connection failure.
+
+An OpenSSL client speaking a protocol that allows compression (SSLv3, TLSv1)
+will unconditionally send the list of all compression methods enabled with
+SSL_COMP_add_compression_method() to the server during the handshake.
+Unlike the mechanisms to set a cipher list, there is no method available to
+restrict the list of compression method on a per connection basis.
+
+An OpenSSL server will match the identifiers listed by a client against
+its own compression methods and will unconditionally activate compression
+when a matching identifier is found. There is no way to restrict the list
+of compression methods supported on a per connection basis.
+
+If enabled during compilation, the OpenSSL library will have the
+COMP_zlib() compression method available.
+
+=head1 RETURN VALUES
+
+SSL_COMP_add_compression_method() may return the following values:
+
+=over 4
+
+=item Z<>0
+
+The operation succeeded.
+
+=item Z<>1
+
+The operation failed. Check the error queue to find out the reason.
+
+=back
+
+SSL_COMP_get_compression_methods() returns the stack of compressions methods or
+NULL on error.
+
+SSL_COMP_get0_name() returns the name of the compression method or NULL on error.
+
+SSL_COMP_get_id() returns the name of the compression method or -1 on error.
+
+=head1 SEE ALSO
+
+L<ssl(7)>
+
+=head1 HISTORY
+
+SSL_COMP_free_compression_methods() was deprecated in OpenSSL 1.1.0;
+do not use it.
+SSL_COMP_get0_name() and SSL_comp_get_id() were added in OpenSSL 1.1.0d.
+
+=head1 COPYRIGHT
+
+Copyright 2001-2016 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (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