xref: /openbsd-src/lib/libcrypto/man/EVP_CIPHER_nid.3 (revision 0c4652a22d8f07127593a31a97458e4615ee7c14)
1.\" $OpenBSD: EVP_CIPHER_nid.3,v 1.3 2023/09/05 14:54:21 schwarze Exp $
2.\" full merge up to: OpenSSL man3/EVP_EncryptInit.pod
3.\"   0874d7f2 Oct 11 13:13:47 2022 +0100
4.\"
5.\" This file is a derived work.
6.\" The changes are covered by the following Copyright and license:
7.\"
8.\" Copyright (c) 2018, 2023 Ingo Schwarze <schwarze@openbsd.org>
9.\"
10.\" Permission to use, copy, modify, and distribute this software for any
11.\" purpose with or without fee is hereby granted, provided that the above
12.\" copyright notice and this permission notice appear in all copies.
13.\"
14.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
15.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
17.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
20.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21.\"
22.\" The original file was written by Dr. Stephen Henson <steve@openssl.org>.
23.\" Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
24.\"
25.\" Redistribution and use in source and binary forms, with or without
26.\" modification, are permitted provided that the following conditions
27.\" are met:
28.\"
29.\" 1. Redistributions of source code must retain the above copyright
30.\"    notice, this list of conditions and the following disclaimer.
31.\"
32.\" 2. Redistributions in binary form must reproduce the above copyright
33.\"    notice, this list of conditions and the following disclaimer in
34.\"    the documentation and/or other materials provided with the
35.\"    distribution.
36.\"
37.\" 3. All advertising materials mentioning features or use of this
38.\"    software must display the following acknowledgment:
39.\"    "This product includes software developed by the OpenSSL Project
40.\"    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
41.\"
42.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
43.\"    endorse or promote products derived from this software without
44.\"    prior written permission. For written permission, please contact
45.\"    openssl-core@openssl.org.
46.\"
47.\" 5. Products derived from this software may not be called "OpenSSL"
48.\"    nor may "OpenSSL" appear in their names without prior written
49.\"    permission of the OpenSSL Project.
50.\"
51.\" 6. Redistributions of any form whatsoever must retain the following
52.\"    acknowledgment:
53.\"    "This product includes software developed by the OpenSSL Project
54.\"    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
55.\"
56.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
57.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
59.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
60.\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
62.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
63.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
64.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
65.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
66.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
67.\" OF THE POSSIBILITY OF SUCH DAMAGE.
68.\"
69.Dd $Mdocdate: September 5 2023 $
70.Dt EVP_CIPHER_NID 3
71.Os
72.Sh NAME
73.Nm EVP_CIPHER_nid ,
74.Nm EVP_CIPHER_CTX_nid ,
75.Nm EVP_CIPHER_name ,
76.Nm EVP_CIPHER_type ,
77.Nm EVP_CIPHER_CTX_type ,
78.Nm EVP_CIPHER_block_size ,
79.Nm EVP_CIPHER_CTX_block_size ,
80.Nm EVP_CIPHER_flags ,
81.Nm EVP_CIPHER_CTX_flags ,
82.Nm EVP_CIPHER_mode ,
83.Nm EVP_CIPHER_CTX_mode
84.Nd inspect EVP_CIPHER objects
85.Sh SYNOPSIS
86.In openssl/evp.h
87.Ft int
88.Fo EVP_CIPHER_nid
89.Fa "const EVP_CIPHER *cipher"
90.Fc
91.Ft int
92.Fo EVP_CIPHER_CTX_nid
93.Fa "const EVP_CIPHER_CTX *ctx"
94.Fc
95.Ft const char *
96.Fo EVP_CIPHER_name
97.Fa "const EVP_CIPHER *cipher"
98.Fc
99.Ft int
100.Fo EVP_CIPHER_type
101.Fa "const EVP_CIPHER *ctx"
102.Fc
103.Ft int
104.Fo EVP_CIPHER_CTX_type
105.Fa "const EVP_CIPHER_CTX *ctx"
106.Fc
107.Ft int
108.Fo EVP_CIPHER_block_size
109.Fa "const EVP_CIPHER *cipher"
110.Fc
111.Ft int
112.Fo EVP_CIPHER_CTX_block_size
113.Fa "const EVP_CIPHER_CTX *ctx"
114.Fc
115.Ft unsigned long
116.Fo EVP_CIPHER_flags
117.Fa "const EVP_CIPHER *cipher"
118.Fc
119.Ft unsigned long
120.Fo EVP_CIPHER_CTX_flags
121.Fa "const EVP_CIPHER_CTX *ctx"
122.Fc
123.Ft unsigned long
124.Fo EVP_CIPHER_mode
125.Fa "const EVP_CIPHER *cipher"
126.Fc
127.Ft unsigned long
128.Fo EVP_CIPHER_CTX_mode
129.Fa "const EVP_CIPHER_CTX *ctx"
130.Fc
131.Sh DESCRIPTION
132.Fn EVP_CIPHER_nid
133returns the numerical identifier (NID) of the
134.Fa cipher .
135The NID is an internal value which may or may not have a corresponding
136ASN.1 OBJECT IDENTIFIER; see
137.Xr OBJ_nid2obj 3
138for details.
139.Pp
140.Fn EVP_CIPHER_CTX_nid
141returns the NID of the cipher that
142.Fa ctx
143is configured to use.
144.Pp
145.Fn EVP_CIPHER_name
146converts the NID of the
147.Fa cipher
148to its short name with
149.Xr OBJ_nid2sn 3 .
150.Pp
151.Fn EVP_CIPHER_type
152returns the NID associated with the ASN.1 OBJECT IDENTIFIER of the
153.Fa cipher ,
154ignoring the cipher parameters.
155For example,
156.Xr EVP_aes_256_cfb1 3 ,
157.Xr EVP_aes_256_cfb8 3 ,
158and
159.Xr EVP_aes_256_cfb128 3
160all return the same NID,
161.Dv NID_aes_256_cfb128 .
162.Pp
163.Fn EVP_CIPHER_CTX_type
164returns the NID associated with the ASN.1 OBJECT IDENTIFIER of the cipher that
165.Fa ctx
166is configured to use.
167.Pp
168.Fn EVP_CIPHER_block_size
169returns the block size of the
170.Fa cipher
171in bytes.
172.Fn EVP_CIPHER_CTX_block_size
173returns the block size of the cipher that
174.Fa ctx
175is configured to use.
176Block sizes are guaranteed to be less than or equal to the constant
177.Dv EVP_MAX_BLOCK_LENGTH .
178Currently,
179.Xr EVP_CipherInit_ex 3
180and the other functions documented in the same manual page
181only support block sizes of 1, 8, and 16 bytes.
182.Pp
183.Fn EVP_CIPHER_flags
184returns the cipher flags used by the
185.Fa cipher .
186The meaning of the flags is described in the
187.Xr EVP_CIPHER_meth_set_flags 3
188manual page.
189.Pp
190.Fn EVP_CIPHER_CTX_flags
191returns the cipher flags of the cipher that
192.Fa ctx
193is configured to use.
194Be careful to not confuse these with the unrelated cipher context flags
195that can be inspected with
196.Xr EVP_CIPHER_CTX_test_flags 3 .
197.Pp
198.Fn EVP_CIPHER_mode
199returns the
200.Fa cipher
201mode, which is the logical AND of the constant
202.Dv EVP_CIPH_MODE
203and the return value of
204.Fn EVP_CIPHER_flags .
205.Pp
206.Fn EVP_CIPHER_CTX_mode
207returns the cipher mode of the cipher that
208.Fa ctx
209is configured to use.
210.Pp
211.Fn EVP_CIPHER_name ,
212.Fn EVP_CIPHER_CTX_type ,
213.Fn EVP_CIPHER_mode ,
214and
215.Fn EVP_CIPHER_CTX_mode
216are implemented as macros.
217.Sh RETURN VALUES
218.Fn EVP_CIPHER_nid
219and
220.Fn EVP_CIPHER_CTX_nid
221return an NID.
222.Pp
223.Fn EVP_CIPHER_name
224returns a pointer to a string that is owned by an internal library object or
225.Dv NULL
226if the NID is neither built into the library nor added to the global
227object table by one of the functions documented in the manual page
228.Xr OBJ_create 3 ,
229of if the object does not contain a short name.
230.Pp
231.Fn EVP_CIPHER_type
232and
233.Fn EVP_CIPHER_CTX_type
234return the NID of the cipher's OBJECT IDENTIFIER or
235.Dv NID_undef
236if it is not associated with an OBJECT IDENTIFIER.
237.Pp
238.Fn EVP_CIPHER_block_size
239and
240.Fn EVP_CIPHER_CTX_block_size
241return the block size in bytes.
242.Pp
243.Fn EVP_CIPHER_flags
244and
245.Fn EVP_CIPHER_CTX_flags
246return one or more
247.Dv EVP_CIPH_*
248flag bits OR'ed together.
249.Pp
250.Fn EVP_CIPHER_mode
251and
252.Fn EVP_CIPHER_CTX_mode
253return one of the constants
254.Dv EVP_CIPH_ECB_MODE ,
255.Dv EVP_CIPH_CBC_MODE ,
256.Dv EVP_CIPH_CFB_MODE ,
257.Dv EVP_CIPH_OFB_MODE ,
258.Dv EVP_CIPH_CTR_MODE ,
259.Dv EVP_CIPH_GCM_MODE ,
260.Dv EVP_CIPH_CCM_MODE ,
261.Dv EVP_CIPH_XTS_MODE ,
262or
263.Dv EVP_CIPH_WRAP_MODE
264to indicate a block cipher or
265.Dv EVP_CIPH_STREAM_CIPHER
266to indicate a stream cipher.
267.Sh SEE ALSO
268.Xr evp 3 ,
269.Xr EVP_CIPHER_CTX_ctrl 3 ,
270.Xr EVP_EncryptInit 3 ,
271.Xr OBJ_nid2obj 3
272.Sh HISTORY
273.Fn EVP_CIPHER_type ,
274.Fn EVP_CIPHER_CTX_type ,
275.Fn EVP_CIPHER_block_size ,
276and
277.Fn EVP_CIPHER_CTX_block_size
278first appeared in SSLeay 0.6.5.
279.Fn EVP_CIPHER_nid
280and
281.Fn EVP_CIPHER_CTX_nid
282first appeared in SSLeay 0.8.0.
283All these functions have been available since
284.Ox 2.4 .
285.Pp
286.Fn EVP_CIPHER_flags ,
287.Fn EVP_CIPHER_CTX_flags ,
288.Fn EVP_CIPHER_mode ,
289and
290.Fn EVP_CIPHER_CTX_mode
291first appeared in OpenSSL 0.9.6 and have been available since
292.Ox 2.9 .
293.Pp
294.Fn EVP_CIPHER_name
295first appeared in OpenSSL 0.9.7 and has been available since
296.Ox 3.2 .
297.Sh CAVEATS
298The behaviour of the functions taking an
299.Vt EVP_CIPHER_CTX
300argument is undefined if they are called on a
301.Fa ctx
302that has no cipher configured yet, for example one freshly returned from
303.Xr EVP_CIPHER_CTX_new 3 .
304In that case, the program may for example be terminated by a
305.Dv NULL
306pointer access.
307