EVP_CIPHER-AES(7ossl) OpenSSL EVP_CIPHER-AES(7ossl)
NAME
EVP_CIPHER-AES - The AES EVP_CIPHER implementations
DESCRIPTION
Support for AES symmetric encryption using the EVP_CIPHER API.
Algorithm Names
The following algorithms are available in the FIPS provider as well as
the default provider:
"AES-128-CBC", "AES-192-CBC" and "AES-256-CBC"
"AES-128-CBC-CTS", "AES-192-CBC-CTS" and "AES-256-CBC-CTS"
"AES-128-CFB", "AES-192-CFB", "AES-256-CFB", "AES-128-CFB1",
"AES-192-CFB1", "AES-256-CFB1", "AES-128-CFB8", "AES-192-CFB8" and
"AES-256-CFB8"
"AES-128-CTR", "AES-192-CTR" and "AES-256-CTR"
"AES-128-ECB", "AES-192-ECB" and "AES-256-ECB"
"AES-192-OFB", "AES-128-OFB" and "AES-256-OFB"
"AES-128-XTS" and "AES-256-XTS"
"AES-128-CCM", "AES-192-CCM" and "AES-256-CCM"
"AES-128-GCM", "AES-192-GCM" and "AES-256-GCM"
"AES-128-WRAP", "AES-192-WRAP", "AES-256-WRAP", "AES-128-WRAP-PAD",
"AES-192-WRAP-PAD", "AES-256-WRAP-PAD", "AES-128-WRAP-INV",
"AES-192-WRAP-INV", "AES-256-WRAP-INV", "AES-128-WRAP-PAD-INV",
"AES-192-WRAP-PAD-INV" and "AES-256-WRAP-PAD-INV"
"AES-128-CBC-HMAC-SHA1", "AES-256-CBC-HMAC-SHA1",
"AES-128-CBC-HMAC-SHA256" and "AES-256-CBC-HMAC-SHA256"
The following algorithms are available in the default provider, but not
the FIPS provider:
"AES-128-OCB", "AES-192-OCB" and "AES-256-OCB"
"AES-128-SIV", "AES-192-SIV" and "AES-256-SIV"
"AES-128-GCM-SIV", "AES-192-GCM-SIV" and "AES-256-GCM-SIV"
Parameters
This implementation supports the parameters described in "PARAMETERS" in
EVP_EncryptInit(3). For implementations in the OpenSSL FIPS provider,
these include the gettable "fips-indicator"
(OSSL_CIPHER_PARAM_FIPS_APPROVED_INDICATOR), which returns 1 if the
operation is FIPS approved, or 0 otherwise. See "FIPS indicators" in
fips_module(7) for more information. For AES-GCM encryption, an
externally supplied IV makes the operation non-approved, so this
indicator returns 0. See "PARAMETERS" in EVP_EncryptInit(3) for the
related "iv-generated" parameter. AES-GCM tag lengths are approved only
when they are 4, 8, or 12 through 16 bytes.
NOTES
The AES-SIV and AES-WRAP mode implementations do not support streaming.
That means to obtain correct results there can be only one
EVP_EncryptUpdate(3) or EVP_DecryptUpdate(3) call after the
initialization of the context.
When wrapping with AES-WRAP-PAD ciphers, the output buffer must be at
least inl rounded up to the cipher block size (8 bytes) plus the block
size. That is, the minimum output buffer size is "((inl + 7) / 8) * 8 +
8" bytes.
The AES-XTS implementations allow streaming to be performed, but each
EVP_EncryptUpdate(3) or EVP_DecryptUpdate(3) call requires each input to
be a multiple of the blocksize. Only the final EVP_EncryptUpdate() or
EVP_DecryptUpdate() call can optionally have an input that is not a
multiple of the blocksize but is larger than one block. In that case
ciphertext stealing (CTS) is used to fill the block.
SEE ALSO
provider-cipher(7), OSSL_PROVIDER-FIPS(7), OSSL_PROVIDER-default(7)
HISTORY
The GCM-SIV mode ciphers were added in OpenSSL version 3.2.
COPYRIGHT
Copyright 2021-2026 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
<https://www.openssl.org/source/license.html>.
3.6.5 2026-09-29 EVP_CIPHER-AES(7ossl)
openssl 3.6.5 - Generated Sat Oct 3 09:06:07 CDT 2026