doc/man3/SSL_get_ciphers.pod - third_party/openssl - Git at Google

 =pod

 =head1 NAME

 SSL_get1_supported_ciphers,
 SSL_get_client_ciphers,
 SSL_get_ciphers,
 SSL_CTX_get_ciphers,
 SSL_bytes_to_cipher_list,
 SSL_get_cipher_list,
 SSL_get_shared_ciphers
 - get list of available SSL_CIPHERs

 =head1 SYNOPSIS

  #include <openssl/ssl.h>

  STACK_OF(SSL_CIPHER) *SSL_get_ciphers(const SSL *ssl);
  STACK_OF(SSL_CIPHER) *SSL_CTX_get_ciphers(const SSL_CTX *ctx);
  STACK_OF(SSL_CIPHER) *SSL_get1_supported_ciphers(SSL *s);
  STACK_OF(SSL_CIPHER) *SSL_get_client_ciphers(const SSL *ssl);
  int SSL_bytes_to_cipher_list(SSL *s, const unsigned char *bytes, size_t len,
                               int isv2format, STACK_OF(SSL_CIPHER) **sk,
                               STACK_OF(SSL_CIPHER) **scsvs);
  const char *SSL_get_cipher_list(const SSL *ssl, int priority);
  char *SSL_get_shared_ciphers(const SSL *s, char *buf, int size);

 =head1 DESCRIPTION

 SSL_get_ciphers() returns the stack of available SSL_CIPHERs for B<ssl>,
 sorted by preference. If B<ssl> is NULL or no ciphers are available, NULL
 is returned.

 SSL_CTX_get_ciphers() returns the stack of available SSL_CIPHERs for B<ctx>.

 SSL_get1_supported_ciphers() returns the stack of enabled SSL_CIPHERs for
 B<ssl> as would be sent in a ClientHello (that is, sorted by preference).
 The list depends on settings like the cipher list, the supported protocol
 versions, the security level, and the enabled signature algorithms.
 SRP and PSK ciphers are only enabled if the appropriate callbacks or settings
 have been applied.
 The list of ciphers that would be sent in a ClientHello can differ from
 the list of ciphers that would be acceptable when acting as a server.
 For example, additional ciphers may be usable by a server if there is
 a gap in the list of supported protocols, and some ciphers may not be
 usable by a server if there is not a suitable certificate configured.
 If B<ssl> is NULL or no ciphers are available, NULL is returned.

 SSL_get_client_ciphers() returns the stack of available SSL_CIPHERs matching the
 list received from the client on B<ssl>. If B<ssl> is NULL, no ciphers are
 available, or B<ssl> is not operating in server mode, NULL is returned.

 SSL_bytes_to_cipher_list() treats the supplied B<len> octets in B<bytes>
 as a wire-protocol cipher suite specification (in the three-octet-per-cipher
 SSLv2 wire format if B<isv2format> is nonzero; otherwise the two-octet
 SSLv3/TLS wire format), and parses the cipher suites supported by the library
 into the returned stacks of SSL_CIPHER objects sk and Signalling Cipher-Suite
 Values scsvs.  Unsupported cipher suites are ignored.  Returns 1 on success
 and 0 on failure.

 SSL_get_cipher_list() returns a pointer to the name of the SSL_CIPHER
 listed for B<ssl> with B<priority>. If B<ssl> is NULL, no ciphers are
 available, or there are less ciphers than B<priority> available, NULL
 is returned.

 SSL_get_shared_ciphers() creates a colon separated and NUL terminated list of
 SSL_CIPHER names that are available in both the client and the server. B<buf> is
 the buffer that should be populated with the list of names and B<size> is the
 size of that buffer. A pointer to B<buf> is returned on success or NULL on
 error. If the supplied buffer is not large enough to contain the complete list
 of names then a truncated list of names will be returned. Note that just because
 a ciphersuite is available (i.e. it is configured in the cipher list) and shared
 by both the client and the server it does not mean that it is enabled (see the
 description of SSL_get1_supported_ciphers() above). This function will return
 available shared ciphersuites whether or not they are enabled. This is a server
 side function only and must only be called after the completion of the initial
 handshake.

 =head1 NOTES

 The details of the ciphers obtained by SSL_get_ciphers(), SSL_CTX_get_ciphers()
 SSL_get1_supported_ciphers() and SSL_get_client_ciphers() can be obtained using
 the L<SSL_CIPHER_get_name(3)> family of functions.

 Call SSL_get_cipher_list() with B<priority> starting from 0 to obtain the
 sorted list of available ciphers, until NULL is returned.

 Note: SSL_get_ciphers(), SSL_CTX_get_ciphers() and SSL_get_client_ciphers()
 return a pointer to an internal cipher stack, which will be freed later on when
 the SSL or SSL_SESSION object is freed.  Therefore, the calling code B<MUST NOT>
 free the return value itself.

 The stack returned by SSL_get1_supported_ciphers() should be freed using
 sk_SSL_CIPHER_free().

 The stacks returned by SSL_bytes_to_cipher_list() should be freed using
 sk_SSL_CIPHER_free().

 =head1 RETURN VALUES

 See DESCRIPTION

 =head1 SEE ALSO

 L<ssl(7)>, L<SSL_CTX_set_cipher_list(3)>,
 L<SSL_CIPHER_get_name(3)>

 =head1 COPYRIGHT

 Copyright 2000-2018 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
 L<https://www.openssl.org/source/license.html>.

 =cut
	=pod

	=head1 NAME

	SSL_get1_supported_ciphers,
	SSL_get_client_ciphers,
	SSL_get_ciphers,
	SSL_CTX_get_ciphers,
	SSL_bytes_to_cipher_list,
	SSL_get_cipher_list,
	SSL_get_shared_ciphers
	- get list of available SSL_CIPHERs

	=head1 SYNOPSIS

	#include <openssl/ssl.h>

	STACK_OF(SSL_CIPHER) SSL_get_ciphers(const SSL ssl);
	STACK_OF(SSL_CIPHER) SSL_CTX_get_ciphers(const SSL_CTX ctx);
	STACK_OF(SSL_CIPHER) SSL_get1_supported_ciphers(SSL s);
	STACK_OF(SSL_CIPHER) SSL_get_client_ciphers(const SSL ssl);
	int SSL_bytes_to_cipher_list(SSL s, const unsigned char bytes, size_t len,
	int isv2format, STACK_OF(SSL_CIPHER) **sk,
	STACK_OF(SSL_CIPHER) **scsvs);
	const char SSL_get_cipher_list(const SSL ssl, int priority);
	char SSL_get_shared_ciphers(const SSL s, char *buf, int size);

	=head1 DESCRIPTION

	SSL_get_ciphers() returns the stack of available SSL_CIPHERs for B<ssl>,
	sorted by preference. If B<ssl> is NULL or no ciphers are available, NULL
	is returned.

	SSL_CTX_get_ciphers() returns the stack of available SSL_CIPHERs for B<ctx>.

	SSL_get1_supported_ciphers() returns the stack of enabled SSL_CIPHERs for
	B<ssl> as would be sent in a ClientHello (that is, sorted by preference).
	The list depends on settings like the cipher list, the supported protocol
	versions, the security level, and the enabled signature algorithms.
	SRP and PSK ciphers are only enabled if the appropriate callbacks or settings
	have been applied.
	The list of ciphers that would be sent in a ClientHello can differ from
	the list of ciphers that would be acceptable when acting as a server.
	For example, additional ciphers may be usable by a server if there is
	a gap in the list of supported protocols, and some ciphers may not be
	usable by a server if there is not a suitable certificate configured.
	If B<ssl> is NULL or no ciphers are available, NULL is returned.

	SSL_get_client_ciphers() returns the stack of available SSL_CIPHERs matching the
	list received from the client on B<ssl>. If B<ssl> is NULL, no ciphers are
	available, or B<ssl> is not operating in server mode, NULL is returned.

	SSL_bytes_to_cipher_list() treats the supplied B<len> octets in B<bytes>
	as a wire-protocol cipher suite specification (in the three-octet-per-cipher
	SSLv2 wire format if B<isv2format> is nonzero; otherwise the two-octet
	SSLv3/TLS wire format), and parses the cipher suites supported by the library
	into the returned stacks of SSL_CIPHER objects sk and Signalling Cipher-Suite
	Values scsvs. Unsupported cipher suites are ignored. Returns 1 on success
	and 0 on failure.

	SSL_get_cipher_list() returns a pointer to the name of the SSL_CIPHER
	listed for B<ssl> with B<priority>. If B<ssl> is NULL, no ciphers are
	available, or there are less ciphers than B<priority> available, NULL
	is returned.

	SSL_get_shared_ciphers() creates a colon separated and NUL terminated list of
	SSL_CIPHER names that are available in both the client and the server. B<buf> is
	the buffer that should be populated with the list of names and B<size> is the
	size of that buffer. A pointer to B<buf> is returned on success or NULL on
	error. If the supplied buffer is not large enough to contain the complete list
	of names then a truncated list of names will be returned. Note that just because
	a ciphersuite is available (i.e. it is configured in the cipher list) and shared
	by both the client and the server it does not mean that it is enabled (see the
	description of SSL_get1_supported_ciphers() above). This function will return
	available shared ciphersuites whether or not they are enabled. This is a server
	side function only and must only be called after the completion of the initial
	handshake.

	=head1 NOTES

	The details of the ciphers obtained by SSL_get_ciphers(), SSL_CTX_get_ciphers()
	SSL_get1_supported_ciphers() and SSL_get_client_ciphers() can be obtained using
	the L<SSL_CIPHER_get_name(3)> family of functions.

	Call SSL_get_cipher_list() with B<priority> starting from 0 to obtain the
	sorted list of available ciphers, until NULL is returned.

	Note: SSL_get_ciphers(), SSL_CTX_get_ciphers() and SSL_get_client_ciphers()
	return a pointer to an internal cipher stack, which will be freed later on when
	the SSL or SSL_SESSION object is freed. Therefore, the calling code B<MUST NOT>
	free the return value itself.

	The stack returned by SSL_get1_supported_ciphers() should be freed using
	sk_SSL_CIPHER_free().

	The stacks returned by SSL_bytes_to_cipher_list() should be freed using
	sk_SSL_CIPHER_free().

	=head1 RETURN VALUES

	See DESCRIPTION

	=head1 SEE ALSO

	L<ssl(7)>, L<SSL_CTX_set_cipher_list(3)>,
	L<SSL_CIPHER_get_name(3)>

	=head1 COPYRIGHT

	Copyright 2000-2018 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
	L<https://www.openssl.org/source/license.html>.

	=cut