/* Provenance: openssl/openssl sm2_plaintext_size (fixed).
 * repo: openssl/openssl
 * commit: 59f5e75f3bced8fc0e130d72a3f582cf7b480b46
 * parent: 8c74c9d1ade0fbdab5b815ddb747351b8b839641
 * commit_url: https://github.com/openssl/openssl/commit/59f5e75f3bced8fc0e130d72a3f582cf7b480b46
 * cve: CVE-2021-3711
 * license: OpenSSL License
 * function: sm2_plaintext_size
 * relpath: crypto/sm2/sm2_crypt.c
 */

int sm2_plaintext_size(const unsigned char *ct, size_t ct_size, size_t *pt_size)
{
    struct SM2_Ciphertext_st *sm2_ctext = NULL;

    sm2_ctext = d2i_SM2_Ciphertext(NULL, &ct, ct_size);

    if (sm2_ctext == NULL) {
        SM2err(SM2_F_SM2_PLAINTEXT_SIZE, SM2_R_INVALID_ENCODING);
        return 0;
    }

    *pt_size = sm2_ctext->C2->length;
    SM2_Ciphertext_free(sm2_ctext);

    return 1;
}