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OpenSSL3.1 C example of AES-XTS using EVP interfaces Unable to segment data for calculation

For AES-XTS encryption, I want to perform segmented input calculations on the data, but it has a problem.

#include <openssl/evp.h>#include <openssl/rand.h>#include <stdio.h>#include <string.h>void handleErrors(void){    ERR_print_errors_fp(stderr);    abort();}int sca_aes_xts_encrypt(const uint8_t *key, size_t klen, uint8_t *iv, const uint8_t *text, size_t len, uint8_t *out) {    EVP_CIPHER_CTX *ctx;    size_t ciphertext_len;    if(!(ctx = EVP_CIPHER_CTX_new()))            handleErrors();    if(1 != EVP_EncryptInit_ex(ctx, EVP_aes_128_xts(), NULL, NULL, NULL))            handleErrors();    if(1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_KEY_LENGTH, klen, NULL))            handleErrors();    if(1 != EVP_EncryptInit_ex(ctx, NULL, NULL, key, iv))            handleErrors();    // if(1 != EVP_EncryptUpdate(ctx, out, &len, text, len))    //         handleErrors();    int block_size = 16;    for(int i = 0; i < len; i += block_size) {        int cipher_len = (len - i) >= block_size ? block_size : (len - i);        if(1 != EVP_EncryptUpdate(ctx, out + i, &cipher_len, text + i, cipher_len))            handleErrors();    }    ciphertext_len = len;    if(1 != EVP_EncryptFinal_ex(ctx, ciphertext + len, &len))            handleErrors();    ciphertext_len += len;    return ciphertext_len;}

The calculation result of the entire data is correct, but the result after segmentation using EVP_EncryptUpdate is wrong.Any help appreciated. Thank you.


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