.\" $OpenBSD: EVP_aes_128_cbc.3,v 1.6 2024/11/09 22:03:49 schwarze Exp $ .\" selective merge up to: OpenSSL 7c6d372a Nov 20 13:20:01 2018 +0000 .\" .\" This file was written by Ronald Tse .\" Copyright (c) 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: November 9 2024 $ .Dt EVP_AES_128_CBC 3 .Os .Sh NAME .Nm EVP_aes_128_cbc , .Nm EVP_aes_192_cbc , .Nm EVP_aes_256_cbc , .Nm EVP_aes_128_cfb1 , .Nm EVP_aes_192_cfb1 , .Nm EVP_aes_256_cfb1 , .Nm EVP_aes_128_cfb8 , .Nm EVP_aes_192_cfb8 , .Nm EVP_aes_256_cfb8 , .Nm EVP_aes_128_cfb128 , .Nm EVP_aes_192_cfb128 , .Nm EVP_aes_256_cfb128 , .Nm EVP_aes_128_cfb , .Nm EVP_aes_192_cfb , .Nm EVP_aes_256_cfb , .Nm EVP_aes_128_ctr , .Nm EVP_aes_192_ctr , .Nm EVP_aes_256_ctr , .Nm EVP_aes_128_ecb , .Nm EVP_aes_192_ecb , .Nm EVP_aes_256_ecb , .Nm EVP_aes_128_ofb , .Nm EVP_aes_192_ofb , .Nm EVP_aes_256_ofb , .Nm EVP_aes_128_cbc_hmac_sha1 , .Nm EVP_aes_256_cbc_hmac_sha1 , .Nm EVP_aes_128_ccm , .Nm EVP_aes_192_ccm , .Nm EVP_aes_256_ccm , .Nm EVP_aes_128_gcm , .Nm EVP_aes_192_gcm , .Nm EVP_aes_256_gcm , .Nm EVP_aes_128_wrap , .Nm EVP_aes_192_wrap , .Nm EVP_aes_256_wrap , .Nm EVP_aes_128_xts , .Nm EVP_aes_256_xts .Nd EVP AES cipher .Sh SYNOPSIS .In openssl/evp.h .Ft const EVP_CIPHER * .Fn EVP_aes_128_cbc void .Ft const EVP_CIPHER * .Fn EVP_aes_192_cbc void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cbc void .Ft const EVP_CIPHER * .Fn EVP_aes_128_cfb1 void .Ft const EVP_CIPHER * .Fn EVP_aes_192_cfb1 void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cfb1 void .Ft const EVP_CIPHER * .Fn EVP_aes_128_cfb8 void .Ft const EVP_CIPHER * .Fn EVP_aes_192_cfb8 void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cfb8 void .Ft const EVP_CIPHER * .Fn EVP_aes_128_cfb128 void .Ft const EVP_CIPHER * .Fn EVP_aes_192_cfb128 void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cfb128 void .Ft const EVP_CIPHER * .Fn EVP_aes_128_cfb void .Ft const EVP_CIPHER * .Fn EVP_aes_192_cfb void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cfb void .Ft const EVP_CIPHER * .Fn EVP_aes_128_ctr void .Ft const EVP_CIPHER * .Fn EVP_aes_192_ctr void .Ft const EVP_CIPHER * .Fn EVP_aes_256_ctr void .Ft const EVP_CIPHER * .Fn EVP_aes_128_ecb void .Ft const EVP_CIPHER * .Fn EVP_aes_192_ecb void .Ft const EVP_CIPHER * .Fn EVP_aes_256_ecb void .Ft const EVP_CIPHER * .Fn EVP_aes_128_ofb void .Ft const EVP_CIPHER * .Fn EVP_aes_192_ofb void .Ft const EVP_CIPHER * .Fn EVP_aes_256_ofb void .Ft const EVP_CIPHER * .Fn EVP_aes_128_cbc_hmac_sha1 void .Ft const EVP_CIPHER * .Fn EVP_aes_256_cbc_hmac_sha1 void .Ft const EVP_CIPHER * .Fn EVP_aes_128_ccm void .Ft const EVP_CIPHER * .Fn EVP_aes_192_ccm void .Ft const EVP_CIPHER * .Fn EVP_aes_256_ccm void .Ft const EVP_CIPHER * .Fn EVP_aes_128_gcm void .Ft const EVP_CIPHER * .Fn EVP_aes_192_gcm void .Ft const EVP_CIPHER * .Fn EVP_aes_256_gcm void .Ft const EVP_CIPHER * .Fn EVP_aes_128_wrap void .Ft const EVP_CIPHER * .Fn EVP_aes_192_wrap void .Ft const EVP_CIPHER * .Fn EVP_aes_256_wrap void .Ft const EVP_CIPHER * .Fn EVP_aes_128_xts void .Ft const EVP_CIPHER * .Fn EVP_aes_256_xts void .Sh DESCRIPTION These functions provide the AES encryption algorithm in the .Xr evp 3 framework. AES is a family of block ciphers operating on 128 bit blocks using key lengths of 128, 192, and 256 bits. .Pp .Fn EVP_aes_128_cbc , .Fn EVP_aes_192_cbc , .Fn EVP_aes_256_cbc , .Fn EVP_aes_128_cfb1 , .Fn EVP_aes_192_cfb1 , .Fn EVP_aes_256_cfb1 , .Fn EVP_aes_128_cfb8 , .Fn EVP_aes_192_cfb8 , .Fn EVP_aes_256_cfb8 , .Fn EVP_aes_128_cfb128 , .Fn EVP_aes_192_cfb128 , .Fn EVP_aes_256_cfb128 , .Fn EVP_aes_128_ctr , .Fn EVP_aes_192_ctr , .Fn EVP_aes_256_ctr , .Fn EVP_aes_128_ecb , .Fn EVP_aes_192_ecb , .Fn EVP_aes_256_ecb , .Fn EVP_aes_128_ofb , .Fn EVP_aes_192_ofb , and .Fn EVP_aes_256_ofb provide AES for 128, 192, and 256-bit keys in the following modes: CBC, CFB with 1-bit shift, CFB with 8-bit shift, CFB with 128-bit shift, CTR, ECB, and OFB. .Pp .Fn EVP_aes_128_cfb , .Fn EVP_aes_192_cfb , and .Fn EVP_aes_256_cfb are aliases for .Fn EVP_aes_128_cfb128 , .Fn EVP_aes_192_cfb128 , and .Fn EVP_aes_256_cfb128 , implemented as macros. .Pp .Fn EVP_aes_128_cbc_hmac_sha1 and .Fn EVP_aes_256_cbc_hmac_sha1 provide authenticated encryption with AES in CBC mode using SHA-1 as HMAC, with keys of 128 and 256-bit length respectively. The authentication tag is 160 bits long. This is not intended for usage outside of TLS and requires calling of some undocumented control functions. These ciphers do not conform to the EVP AEAD interface. .Pp .Fn EVP_aes_128_ccm , .Fn EVP_aes_192_ccm , .Fn EVP_aes_256_ccm , .Fn EVP_aes_128_gcm , .Fn EVP_aes_192_gcm , and .Fn EVP_aes_256_gcm provide AES for 128, 192 and 256-bit keys in CBC-MAC Mode (CCM) and Galois Counter Mode (GCM), respectively. These ciphers require additional control operations to function correctly; see .Xr EVP_EncryptInit 3 for details. .Pp .Fn EVP_aes_128_wrap , .Fn EVP_aes_192_wrap , and .Fn EVP_aes_256_wrap provide AES key wrap with 128, 192 and 256-bit keys according to RFC 3394 section 2.2.1 ("wrap"). When the returned .Vt EVP_CIPHER object is later passed to .Xr EVP_CipherInit_ex 3 , .Xr EVP_EncryptInit_ex 3 , or .Xr EVP_DecryptInit_ex 3 together with an .Vt EVP_CIPHER_CTX object, the flag .Dv EVP_CIPHER_CTX_FLAG_WRAP_ALLOW must have been set in the .Vt EVP_CIPHER_CTX using .Xr EVP_CIPHER_CTX_set_flags 3 . Otherwise, or when passing the returned .Vt EVP_CIPHER object to .Xr EVP_CipherInit 3 , .Xr EVP_EncryptInit 3 , or .Xr EVP_DecryptInit 3 , initialization fails with a .Dq wrap not allowed error. .Pp .Fn EVP_aes_128_xts and .Fn EVP_aes_256_xts provide XEX-based tweaked-codebook mode with ciphertext stealing (XTS-AES) as specified in IEEE Std. 1619-2007 and described in NIST SP 800-38E. It was designed for encrypting data on a storage device, provides confidentiality but not authentication of data, and requires a key of double length for protection of a certain key size. In particular, XTS-AES-128 takes input of a 256-bit key to achieve AES 128-bit security, and XTS-AES-256 takes input of a 512-bit key to achieve AES 256-bit security. .Sh RETURN VALUES These functions return an .Vt EVP_CIPHER structure that provides the implementation of the symmetric cipher. .Sh SEE ALSO .Xr AES_encrypt 3 , .Xr evp 3 , .Xr EVP_EncryptInit 3 .Sh HISTORY .Fn EVP_aes_128_cbc , .Fn EVP_aes_192_cbc , .Fn EVP_aes_256_cbc , .Fn EVP_aes_128_cfb , .Fn EVP_aes_192_cfb , .Fn EVP_aes_256_cfb , .Fn EVP_aes_128_ebc , .Fn EVP_aes_192_ebc , .Fn EVP_aes_256_ebc , .Fn EVP_aes_128_ofb , .Fn EVP_aes_192_ofb , and .Fn EVP_aes_256_ofb first appeared in OpenSSL 0.9.7 and have been available since .Ox 3.2 . .Pp .Fn EVP_aes_128_cfb1 , .Fn EVP_aes_192_cfb1 , .Fn EVP_aes_256_cfb1 , .Fn EVP_aes_128_cfb8 , .Fn EVP_aes_192_cfb8 , .Fn EVP_aes_256_cfb8 , .Fn EVP_aes_128_cfb128 , .Fn EVP_aes_192_cfb128 , and .Fn EVP_aes_256_cfb128 first appeared in OpenSSL 0.9.7e and have been available since .Ox 3.8 . .Pp .Fn EVP_aes_128_ctr , .Fn EVP_aes_192_ctr , .Fn EVP_aes_256_ctr , .Fn EVP_aes_128_cbc_hmac_sha1 , .Fn EVP_aes_256_cbc_hmac_sha1 , .Fn EVP_aes_128_ccm , .Fn EVP_aes_192_ccm , .Fn EVP_aes_256_ccm , .Fn EVP_aes_128_gcm , .Fn EVP_aes_192_gcm , .Fn EVP_aes_256_gcm , .Fn EVP_aes_128_xts , and .Fn EVP_aes_256_xts first appeared in OpenSSL 1.0.1 and have been available since .Ox 5.3 . .Pp .Fn EVP_aes_128_wrap , .Fn EVP_aes_192_wrap , and .Fn EVP_aes_256_wrap first appeared in OpenSSL 1.0.2 and have been available since .Ox 6.5 .