EVP_SM4_CBC(3ossl)

🎀 NAME 🎀

okay so bestie, this is the EVP_SM4_CBC(3ossl) page, and it's giving the EVP SM4 cipher. The whole squad is: EVP_sm4_cbc, EVP_sm4_ecb, EVP_sm4_cfb, EVP_sm4_cfb128, EVP_sm4_ofb, EVP_sm4_ctr.

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✨ SYNOPSIS ✨

#include <openssl/evp.h>

const EVP_CIPHER *EVP_sm4_cbc(void);
const EVP_CIPHER *EVP_sm4_ecb(void);
const EVP_CIPHER *EVP_sm4_cfb(void);
const EVP_CIPHER *EVP_sm4_cfb128(void);
const EVP_CIPHER *EVP_sm4_ofb(void);
const EVP_CIPHER *EVP_sm4_ctr(void);

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💅 DESCRIPTION 💅

okay so it's the SM4 blockcipher (GB/T 32907-2016) for EVP, and it's iconic. Every mode below uses a key length of 128 bits and acts on blocks of 128 bits. no cap.

• EVP_sm4_cbc(), EVP_sm4_ecb(), EVP_sm4_cfb(), EVP_sm4_cfb128(), EVP_sm4_ofb(), EVP_sm4_ctr() — The SM4 blockcipher with a 128-bit key in CBC, ECB, CFB, OFB and CTR modes respectively. slay.

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🫶 NOTES 🫶

bestie, real talk: developers should be aware of the negative performance implications of calling these functions multiple times and should consider using EVP_CIPHER_fetch(3) with EVP_CIPHER-SM4(7) instead. See "Performance" in crypto(7) for further information.

lowkey important: that's not a vibe, that's a performance warning. 💀

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🌈 RETURN VALUES 🌈

These functions return a EVP_CIPHER structure that contains the implementation of the symmetric cipher. See EVP_CIPHER_meth_new(3) for details of the EVP_CIPHER structure. periodt.

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👑 SEE ALSO 👑

evp(7), EVP_EncryptInit(3), EVP_CIPHER_meth_new(3)

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🍓 COPYRIGHT 🍓

Copyright 2017-2023 The OpenSSL Project Authors. All Rights Reserved.

Copyright 2017 Ribose Inc. 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>.

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mwah 💋 this page is from OpenSSL 3.5.6, dated 2026-04-07 — EVP_SM4_CBC(3ossl) out 💅