6 SSL_CIPHER_standard_name,
9 SSL_CIPHER_get_version,
10 SSL_CIPHER_description,
11 SSL_CIPHER_get_cipher_nid,
12 SSL_CIPHER_get_digest_nid,
13 SSL_CIPHER_get_handshake_digest,
14 SSL_CIPHER_get_kx_nid,
15 SSL_CIPHER_get_auth_nid,
19 SSL_CIPHER_get_protocol_id
20 - get SSL_CIPHER properties
24 #include <openssl/ssl.h>
26 const char *SSL_CIPHER_get_name(const SSL_CIPHER *cipher);
27 const char *SSL_CIPHER_standard_name(const SSL_CIPHER *cipher);
28 const char *OPENSSL_cipher_name(const char *stdname);
29 int SSL_CIPHER_get_bits(const SSL_CIPHER *cipher, int *alg_bits);
30 char *SSL_CIPHER_get_version(const SSL_CIPHER *cipher);
31 char *SSL_CIPHER_description(const SSL_CIPHER *cipher, char *buf, int size);
32 int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *c);
33 int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *c);
34 const EVP_MD *SSL_CIPHER_get_handshake_digest(const SSL_CIPHER *c);
35 int SSL_CIPHER_get_kx_nid(const SSL_CIPHER *c);
36 int SSL_CIPHER_get_auth_nid(const SSL_CIPHER *c);
37 int SSL_CIPHER_is_aead(const SSL_CIPHER *c);
38 const SSL_CIPHER *SSL_CIPHER_find(SSL *ssl, const unsigned char *ptr);
39 uint32_t SSL_CIPHER_get_id(const SSL_CIPHER *c);
40 uint32_t SSL_CIPHER_get_protocol_id(const SSL_CIPHER *c);
44 SSL_CIPHER_get_name() returns a pointer to the name of B<cipher>. If the
45 B<cipher> is NULL, it returns "(NONE)".
47 SSL_CIPHER_standard_name() returns a pointer to the standard RFC name of
48 B<cipher>. If the B<cipher> is NULL, it returns "(NONE)". If the B<cipher>
49 has no standard name, it returns B<NULL>. If B<cipher> was defined in both
50 SSLv3 and TLS, it returns the TLS name.
52 OPENSSL_cipher_name() returns a pointer to the OpenSSL name of B<stdname>.
53 If the B<stdname> is NULL, or B<stdname> has no corresponding OpenSSL name,
54 it returns "(NONE)". Where both exist, B<stdname> should be the TLS name rather
57 SSL_CIPHER_get_bits() returns the number of secret bits used for B<cipher>.
58 If B<cipher> is NULL, 0 is returned.
60 SSL_CIPHER_get_version() returns string which indicates the SSL/TLS protocol
61 version that first defined the cipher. It returns "(NONE)" if B<cipher> is NULL.
63 SSL_CIPHER_get_cipher_nid() returns the cipher NID corresponding to B<c>.
64 If there is no cipher (e.g. for cipher suites with no encryption) then
65 B<NID_undef> is returned.
67 SSL_CIPHER_get_digest_nid() returns the digest NID corresponding to the MAC
68 used by B<c> during record encryption/decryption. If there is no digest (e.g.
69 for AEAD cipher suites) then B<NID_undef> is returned.
71 SSL_CIPHER_get_handshake_digest() returns an EVP_MD for the digest used during
72 the SSL/TLS handshake when using the SSL_CIPHER B<c>. Note that this may be
73 different to the digest used to calculate the MAC for encrypted records.
75 SSL_CIPHER_get_kx_nid() returns the key exchange NID corresponding to the method
76 used by B<c>. If there is no key exchange, then B<NID_undef> is returned.
77 If any appropriate key exchange algorithm can be used (as in the case of TLS 1.3
78 cipher suites) B<NID_kx_any> is returned. Examples (not comprehensive):
85 SSL_CIPHER_get_auth_nid() returns the authentication NID corresponding to the method
86 used by B<c>. If there is no authentication, then B<NID_undef> is returned.
87 If any appropriate authentication algorithm can be used (as in the case of
88 TLS 1.3 cipher suites) B<NID_auth_any> is returned. Examples (not comprehensive):
94 SSL_CIPHER_is_aead() returns 1 if the cipher B<c> is AEAD (e.g. GCM or
95 ChaCha20/Poly1305), and 0 if it is not AEAD.
97 SSL_CIPHER_find() returns a B<SSL_CIPHER> structure which has the cipher ID stored
98 in B<ptr>. The B<ptr> parameter is a two element array of B<char>, which stores the
99 two-byte TLS cipher ID (as allocated by IANA) in network byte order. This parameter
100 is usually retrieved from a TLS packet by using functions like
101 L<SSL_client_hello_get0_ciphers(3)>. SSL_CIPHER_find() returns NULL if an
102 error occurs or the indicated cipher is not found.
104 SSL_CIPHER_get_id() returns the OpenSSL-specific ID of the given cipher B<c>. That ID is
105 not the same as the IANA-specific ID.
107 SSL_CIPHER_get_protocol_id() returns the two-byte ID used in the TLS protocol of the given
110 SSL_CIPHER_description() returns a textual description of the cipher used
111 into the buffer B<buf> of length B<len> provided. If B<buf> is provided, it
112 must be at least 128 bytes, otherwise a buffer will be allocated using
113 OPENSSL_malloc(). If the provided buffer is too small, or the allocation fails,
116 The string returned by SSL_CIPHER_description() consists of several fields
117 separated by whitespace:
123 Textual representation of the cipher name.
125 =item <protocol version>
127 Protocol version, such as B<TLSv1.2>, when the cipher was first defined.
129 =item Kx=<key exchange>
131 Key exchange method such as B<RSA>, B<ECDHE>, etc.
133 =item Au=<authentication>
135 Authentication method such as B<RSA>, B<None>, etc.. None is the
136 representation of anonymous ciphers.
138 =item Enc=<symmetric encryption method>
140 Encryption method, with number of secret bits, such as B<AESGCM(128)>.
142 =item Mac=<message authentication code>
144 Message digest, such as B<SHA256>.
148 Some examples for the output of SSL_CIPHER_description():
150 ECDHE-RSA-AES256-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD
151 RSA-PSK-AES256-CBC-SHA384 TLSv1.0 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA384
155 SSL_CIPHER_get_name(), SSL_CIPHER_standard_name(), OPENSSL_cipher_name(),
156 SSL_CIPHER_get_version() and SSL_CIPHER_description() return the corresponding
157 value in a null-terminated string for a specific cipher or "(NONE)"
158 if the cipher is not found.
160 SSL_CIPHER_get_bits() returns a positive integer representing the number of
161 secret bits or 0 if an error occurred.
163 SSL_CIPHER_get_cipher_nid(), SSL_CIPHER_get_digest_nid(),
164 SSL_CIPHER_get_kx_nid() and SSL_CIPHER_get_auth_nid() return the NID value or
165 B<NID_undef> if an error occurred.
167 SSL_CIPHER_get_handshake_digest() returns a valid B<EVP_MD> structure or NULL
168 if an error occurred.
170 SSL_CIPHER_is_aead() returns 1 if the cipher is AEAD or 0 otherwise.
172 SSL_CIPHER_find() returns a valid B<SSL_CIPHER> structure or NULL if an error
175 SSL_CIPHER_get_id() returns a 4-byte integer representing the OpenSSL-specific ID.
177 SSL_CIPHER_get_protocol_id() returns a 2-byte integer representing the TLS
178 protocol-specific ID.
182 SSL_CIPHER_get_version() was updated to always return the correct protocol
183 string in OpenSSL 1.1.0.
185 SSL_CIPHER_description() was changed to return B<NULL> on error,
186 rather than a fixed string, in OpenSSL 1.1.0.
188 SSL_CIPHER_get_handshake_digest() was added in OpenSSL 1.1.1.
190 SSL_CIPHER_standard_name() was globally available in OpenSSL 1.1.1. Before
191 OpenSSL 1.1.1, tracing (B<enable-ssl-trace> argument to Configure) was
192 required to enable this function.
194 OPENSSL_cipher_name() was added in OpenSSL 1.1.1.
198 L<ssl(7)>, L<SSL_get_current_cipher(3)>,
199 L<SSL_get_ciphers(3)>, L<ciphers(1)>
203 Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
205 Licensed under the OpenSSL license (the "License"). You may not use
206 this file except in compliance with the License. You can obtain a copy
207 in the file LICENSE in the source distribution or at
208 L<https://www.openssl.org/source/license.html>.