/* Provenance: openssl/openssl pkcs12_gen_mac (fixed).
 * repo: openssl/openssl
 * commit: 09df4395b5071217b76dc7d3d2e630eb8c5a79c2
 * parent: 6c70934a46eaa1734c2efbe9d7baac51c607062e
 * commit_url: https://github.com/openssl/openssl/commit/09df4395b5071217b76dc7d3d2e630eb8c5a79c2
 * cve: CVE-2024-0727
 * license: Apache-2.0
 * function: pkcs12_gen_mac
 * relpath: crypto/pkcs12/p12_mutl.c
 */

static int pkcs12_gen_mac(PKCS12 *p12, const char *pass, int passlen,
                          unsigned char *mac, unsigned int *maclen,
                          int (*pkcs12_key_gen)(const char *pass, int passlen,
                                                unsigned char *salt, int slen,
                                                int id, int iter, int n,
                                                unsigned char *out,
                                                const EVP_MD *md_type))
{
    int ret = 0;
    const EVP_MD *md;
    EVP_MD *md_fetch;
    HMAC_CTX *hmac = NULL;
    unsigned char key[EVP_MAX_MD_SIZE], *salt;
    int saltlen, iter;
    char md_name[80];
    int md_size = 0;
    int md_nid;
    const X509_ALGOR *macalg;
    const ASN1_OBJECT *macoid;

    if (!PKCS7_type_is_data(p12->authsafes)) {
        ERR_raise(ERR_LIB_PKCS12, PKCS12_R_CONTENT_TYPE_NOT_DATA);
        return 0;
    }

    if (p12->authsafes->d.data == NULL) {
        ERR_raise(ERR_LIB_PKCS12, PKCS12_R_DECODE_ERROR);
        return 0;
    }

    salt = p12->mac->salt->data;
    saltlen = p12->mac->salt->length;
    if (p12->mac->iter == NULL)
        iter = 1;
    else
        iter = ASN1_INTEGER_get(p12->mac->iter);
    X509_SIG_get0(p12->mac->dinfo, &macalg, NULL);
    X509_ALGOR_get0(&macoid, NULL, NULL, macalg);
    if (OBJ_obj2txt(md_name, sizeof(md_name), macoid, 0) < 0)
        return 0;

    (void)ERR_set_mark();
    md = md_fetch = EVP_MD_fetch(p12->authsafes->ctx.libctx, md_name,
                                 p12->authsafes->ctx.propq);
    if (md == NULL)
        md = EVP_get_digestbynid(OBJ_obj2nid(macoid));

    if (md == NULL) {
        (void)ERR_clear_last_mark();
        ERR_raise(ERR_LIB_PKCS12, PKCS12_R_UNKNOWN_DIGEST_ALGORITHM);
        return 0;
    }
    (void)ERR_pop_to_mark();

    md_size = EVP_MD_get_size(md);
    md_nid = EVP_MD_get_type(md);
    if (md_size < 0)
        goto err;
    if ((md_nid == NID_id_GostR3411_94
         || md_nid == NID_id_GostR3411_2012_256
         || md_nid == NID_id_GostR3411_2012_512)
        && ossl_safe_getenv("LEGACY_GOST_PKCS12") == NULL) {
        md_size = TK26_MAC_KEY_LEN;
        if (!pkcs12_gen_gost_mac_key(pass, passlen, salt, saltlen, iter,
                                     md_size, key, md)) {
            ERR_raise(ERR_LIB_PKCS12, PKCS12_R_KEY_GEN_ERROR);
            goto err;
        }
    } else {
        if (pkcs12_key_gen != NULL) {
            if (!(*pkcs12_key_gen)(pass, passlen, salt, saltlen, PKCS12_MAC_ID,
                                   iter, md_size, key, md)) {
                ERR_raise(ERR_LIB_PKCS12, PKCS12_R_KEY_GEN_ERROR);
                goto err;
            }
        } else {
            /* Default to UTF-8 password */
            if (!PKCS12_key_gen_utf8_ex(pass, passlen, salt, saltlen, PKCS12_MAC_ID,
                                       iter, md_size, key, md,
                                       p12->authsafes->ctx.libctx,
                                       p12->authsafes->ctx.propq)) {
                ERR_raise(ERR_LIB_PKCS12, PKCS12_R_KEY_GEN_ERROR);
                goto err;
            }
        }
    }
    if ((hmac = HMAC_CTX_new()) == NULL
        || !HMAC_Init_ex(hmac, key, md_size, md, NULL)
        || !HMAC_Update(hmac, p12->authsafes->d.data->data,
                        p12->authsafes->d.data->length)
        || !HMAC_Final(hmac, mac, maclen)) {
        goto err;
    }
    ret = 1;

err:
    OPENSSL_cleanse(key, sizeof(key));
    HMAC_CTX_free(hmac);
    EVP_MD_free(md_fetch);
    return ret;
}