.\" $OpenBSD: SSL_CIPHER_get_name.3,v 1.12 2021/05/12 15:12:35 tb Exp $ .\" full merge up to: OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100 .\" selective merge up to: OpenSSL 61f805c1 Jan 16 01:01:46 2018 +0800 .\" .\" This file was written by Lutz Jaenicke , .\" Dr. Stephen Henson , Todd Short , .\" and Paul Yang . .\" Copyright (c) 2000, 2005, 2009, 2013, 2014, 2015, 2016, 2017 .\" The OpenSSL Project. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in .\" the documentation and/or other materials provided with the .\" distribution. .\" .\" 3. 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IN NO EVENT SHALL THE OpenSSL PROJECT OR .\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, .\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT .\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; .\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, .\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED .\" OF THE POSSIBILITY OF SUCH DAMAGE. .\" .Dd $Mdocdate: May 12 2021 $ .Dt SSL_CIPHER_GET_NAME 3 .Os .Sh NAME .Nm SSL_CIPHER_get_name , .Nm SSL_CIPHER_get_bits , .Nm SSL_CIPHER_get_version , .Nm SSL_CIPHER_get_cipher_nid , .Nm SSL_CIPHER_get_digest_nid , .Nm SSL_CIPHER_get_kx_nid , .Nm SSL_CIPHER_get_auth_nid , .Nm SSL_CIPHER_is_aead , .Nm SSL_CIPHER_find , .Nm SSL_CIPHER_get_id , .Nm SSL_CIPHER_description .Nd get SSL_CIPHER properties .Sh SYNOPSIS .In openssl/ssl.h .Ft const char * .Fn SSL_CIPHER_get_name "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_get_bits "const SSL_CIPHER *cipher" "int *alg_bits" .Ft const char * .Fn SSL_CIPHER_get_version "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_get_cipher_nid "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_get_digest_nid "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_get_kx_nid "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_get_auth_nid "const SSL_CIPHER *cipher" .Ft int .Fn SSL_CIPHER_is_aead "const SSL_CIPHER *cipher" .Ft const SSL_CIPHER * .Fn SSL_CIPHER_find "SSL *ssl" "const unsigned char *ptr" .Ft unsigned long .Fn SSL_CIPHER_get_id "const SSL_CIPHER *cipher" .Ft char * .Fn SSL_CIPHER_description "const SSL_CIPHER *cipher" "char *buf" "int size" .Sh DESCRIPTION .Fn SSL_CIPHER_get_name returns a pointer to the name of .Fa cipher . .Pp .Fn SSL_CIPHER_get_bits returns the number of secret bits used for .Fa cipher . If .Fa alg_bits is not .Dv NULL , the number of bits processed by the chosen algorithm is stored into it. .Pp .Fn SSL_CIPHER_get_version returns a string which indicates the SSL/TLS protocol version that first defined the cipher. This is currently .Qq TLSv1/SSLv3 . In some cases it should possibly return .Qq TLSv1.2 but the function does not; use .Fn SSL_CIPHER_description instead. .Pp .Fn SSL_CIPHER_get_cipher_nid returns the cipher NID corresponding to the .Fa cipher . If there is no cipher (e.g. for cipher suites with no encryption), then .Dv NID_undef is returned. .Pp .Fn SSL_CIPHER_get_digest_nid returns the digest NID corresponding to the MAC used by the .Fa cipher during record encryption/decryption. If there is no digest (e.g. for AEAD cipher suites), then .Dv NID_undef is returned. .Pp .Fn SSL_CIPHER_get_kx_nid returns the key exchange NID corresponding to the method used by the .Fa cipher . If there is no key exchange, then .Dv NID_undef is returned. Examples of possible return values include .Dv NID_kx_rsa , .Dv NID_kx_dhe , and .Dv NID_kx_ecdhe . .Pp .Fn SSL_CIPHER_get_auth_nid returns the authentication NID corresponding to the method used by the .Fa cipher . If there is no authentication, .Dv NID_undef is returned. Examples of possible return values include .Dv NID_auth_rsa and .Dv NID_auth_ecdsa . .Pp .Fn SSL_CIPHER_is_aead returns 1 if the .Fa cipher is AEAD (e.g. GCM or ChaCha20/Poly1305), or 0 if it is not AEAD. .Pp .Fn SSL_CIPHER_find returns a pointer to a .Vt SSL_CIPHER structure which has the cipher ID specified in .Fa ptr . The .Fa ptr parameter is an array of length two which stores the two-byte TLS cipher ID (as allocated by IANA) in network byte order. .Fa SSL_CIPHER_find returns .Dv NULL if an error occurs or the indicated cipher is not found. .Pp .Fn SSL_CIPHER_get_id returns the ID of the given .Fa cipher , which must not be .Dv NULL . The ID here is an OpenSSL-specific concept, which stores a prefix of 0x0300 in the higher two bytes and the IANA-specified chipher suite ID in the lower two bytes. For instance, TLS_RSA_WITH_NULL_MD5 has IANA ID "0x00, 0x01", so .Fn SSL_CIPHER_get_id returns 0x03000001. .Pp .Fn SSL_CIPHER_description copies a textual description of .Fa cipher into the buffer .Fa buf , which must be at least .Fa size bytes long. The .Fa cipher argument must not be a .Dv NULL pointer. If .Fa buf is .Dv NULL , a buffer is allocated using .Xr asprintf 3 ; that buffer should be freed using the .Xr free 3 function. If .Fa len is too small to hold the description, a pointer to the static string .Qq Buffer too small is returned. If memory allocation fails, which can happen even if a .Fa buf of sufficient size is provided, a pointer to the static string .Qq OPENSSL_malloc Error is returned and the content of .Fa buf remains unchanged. .Pp The string returned by .Fn SSL_CIPHER_description consists of several fields separated by whitespace: .Bl -tag -width Ds .It Aq Ar ciphername Textual representation of the cipher name. .It Aq Ar protocol version Protocol version: .Sy SSLv3 , .Sy TLSv1.2 , or .Sy TLSv1.3 . The TLSv1.0 ciphers are flagged with SSLv3. No new ciphers were added by TLSv1.1. .It Kx= Ns Aq Ar key exchange Key exchange method: .Sy DH , .Sy ECDH , .Sy GOST , .Sy RSA , or .Sy TLSv1.3 . .It Au= Ns Aq Ar authentication Authentication method: .Sy ECDSA , .Sy GOST01 , .Sy RSA , .Sy TLSv1.3 , or .Sy None . .Sy None is the representation of anonymous ciphers. .It Enc= Ns Aq Ar symmetric encryption method Encryption method with number of secret bits: .Sy 3DES(168) , .Sy RC4(128) , .Sy AES(128) , .Sy AES(256) , .Sy AESCGM(128) , .Sy AESCGM(256) , .Sy Camellia(128) , .Sy Camellia(256) , .Sy ChaCha20-Poly1305 , .Sy GOST-28178-89-CNT , or .Sy None . .It Mac= Ns Aq Ar message authentication code Message digest: .Sy MD5 , .Sy SHA1 , .Sy SHA256 , .Sy SHA384 , .Sy AEAD , .Sy GOST94 , .Sy GOST89IMIT , or .Sy STREEBOG256 . .El .Sh RETURN VALUES .Fn SSL_CIPHER_get_name returns an internal pointer to a NUL-terminated string. .Fn SSL_CIPHER_get_version returns a pointer to a static NUL-terminated string. If .Fa cipher is a .Dv NULL pointer, both functions return a pointer to the static string .Qq Pq NONE . .Pp .Fn SSL_CIPHER_get_bits returns a positive integer representing the number of secret bits or 0 if .Fa cipher is a .Dv NULL pointer. .Pp .Fn SSL_CIPHER_get_cipher_nid , .Fn SSL_CIPHER_get_digest_nid , .Fn SSL_CIPHER_get_kx_nid , and .Fn SSL_CIPHER_get_auth_nid return an NID constant or .Dv NID_undef if an error occurred. .Pp .Fn SSL_CIPHER_is_aead returns 1 if the .Fa cipher is AEAD or 0 otherwise. .Pp .Fn SSL_CIPHER_find returns a pointer to a valid .Vt SSL_CIPHER structure or .Dv NULL if an error occurred. .Pp .Fn SSL_CIPHER_get_id returns a 32-bit unsigned integer. .Pp .Fn SSL_CIPHER_description returns .Fa buf or a newly allocated string on success or a pointer to a static string on error. .Sh EXAMPLES An example for the output of .Fn SSL_CIPHER_description : .Bd -literal ECDHE-RSA-AES256-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD .Ed .Pp A complete list can be retrieved by invoking the following command: .Pp .Dl $ openssl ciphers -v ALL:COMPLEMENTOFALL .Sh SEE ALSO .Xr openssl 1 , .Xr ssl 3 , .Xr SSL_get_ciphers 3 , .Xr SSL_get_current_cipher 3 .Sh HISTORY .Fn SSL_CIPHER_description first appeared in SSLeay 0.8.0. .Fn SSL_CIPHER_get_name , .Fn SSL_CIPHER_get_bits , and .Fn SSL_CIPHER_get_version first appeared in SSLeay 0.8.1. These functions have been available since .Ox 2.4 . .Pp .Fn SSL_CIPHER_get_id first appeared in OpenSSL 1.0.1 and has been available since .Ox 5.3 . .Pp .Fn SSL_CIPHER_get_cipher_nid , .Fn SSL_CIPHER_get_digest_nid , .Fn SSL_CIPHER_get_kx_nid , .Fn SSL_CIPHER_get_auth_nid , and .Fn SSL_CIPHER_is_aead first appeared in OpenSSL 1.1.0 and have been available since .Ox 6.3 . .Fn SSL_CIPHER_find first appeared in OpenSSL 1.1.0 and has been available since .Ox 7.0 . .Sh BUGS If .Fn SSL_CIPHER_description cannot handle a built-in cipher, the according description of the cipher property is .Qq unknown . This case should not occur.