static int add_custom_ext_intern(SSL_CTX *ctx, ENDPOINT role,
                                 unsigned int ext_type,
                                 unsigned int context,
                                 SSL_custom_ext_add_cb_ex add_cb,
                                 SSL_custom_ext_free_cb_ex free_cb,
                                 void *add_arg,
                                 SSL_custom_ext_parse_cb_ex parse_cb,
                                 void *parse_arg)
{
    custom_ext_methods *exts = &ctx->cert->custext;
    custom_ext_method *meth, *tmp;
    if (add_cb == NULL && free_cb != NULL)
        return 0;
#ifndef OPENSSL_NO_CT
    if (ext_type == TLSEXT_TYPE_signed_certificate_timestamp
            && (context & SSL_EXT_CLIENT_HELLO) != 0
            && SSL_CTX_ct_is_enabled(ctx))
        return 0;
#endif
    if (SSL_extension_supported(ext_type)
            && ext_type != TLSEXT_TYPE_signed_certificate_timestamp)
        return 0;
    if (ext_type > 0xffff)
        return 0;
    if (custom_ext_find(exts, role, ext_type, NULL))
        return 0;
    tmp = OPENSSL_realloc(exts->meths,
                          (exts->meths_count + 1) * sizeof(custom_ext_method));
    if (tmp == NULL)
        return 0;
    exts->meths = tmp;
    meth = exts->meths + exts->meths_count;
    memset(meth, 0, sizeof(*meth));
    meth->role = role;
    meth->context = context;
    meth->parse_cb = parse_cb;
    meth->add_cb = add_cb;
    meth->free_cb = free_cb;
    meth->ext_type = ext_type;
    meth->add_arg = add_arg;
    meth->parse_arg = parse_arg;
    exts->meths_count++;
    return 1;
}
['static int test_custom_exts(int tst) {\n    SSL_CTX *cctx = NULL, *sctx = NULL;\n    SSL *clientssl = NULL, *serverssl = NULL;\n    int testresult = 0;\n    static int server = 1;\n    static int client = 0;\n    SSL_SESSION *sess = NULL;\n    unsigned int context;\n    clntaddoldcb = clntparseoldcb = srvaddoldcb = srvparseoldcb = 0;\n    clntaddnewcb = clntparsenewcb = srvaddnewcb = srvparsenewcb = 0;\n    if (!create_ssl_ctx_pair(TLS_server_method(), TLS_client_method(), &sctx,\n                             &cctx, cert, privkey)) {\n        printf("Unable to create SSL_CTX pair\\n");\n        return 0;\n    }\n    if (tst < 2) {\n        SSL_CTX_set_options(cctx, SSL_OP_NO_TLSv1_3);\n        SSL_CTX_set_options(sctx, SSL_OP_NO_TLSv1_3);\n    }\n    if (tst == 3) {\n        context = SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO\n                  | SSL_EXT_TLS1_3_SERVER_HELLO\n                  | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS\n                  | SSL_EXT_TLS1_3_CERTIFICATE\n                  | SSL_EXT_TLS1_3_NEW_SESSION_TICKET;\n    } else {\n        context = SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO\n                  | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS;\n    }\n    if (tst == 0) {\n        if (!SSL_CTX_add_client_custom_ext(cctx, TEST_EXT_TYPE1, old_add_cb,\n                                           old_free_cb, &client, old_parse_cb,\n                                           &client)) {\n            printf("Unable to create old style client side custom extension\\n");\n            return 0;\n        }\n    } else {\n        if (!SSL_CTX_add_custom_ext(cctx, TEST_EXT_TYPE1, context, new_add_cb,\n                                    new_free_cb, &client, new_parse_cb,\n                                    &client)) {\n            printf("Unable to create new style client side custom extension\\n");\n            return 0;\n        }\n    }\n    if (SSL_CTX_add_client_custom_ext(cctx, TEST_EXT_TYPE1, old_add_cb,\n                                      old_free_cb, &client, old_parse_cb,\n                                      &client)) {\n        printf("Unexpected success adding duplicate client custom extension\\n");\n        return 0;\n    }\n    if (SSL_CTX_add_custom_ext(cctx, TEST_EXT_TYPE1, context, new_add_cb,\n                               new_free_cb, &client, new_parse_cb, &client)) {\n        printf("Unexpected success adding duplicate client custom extension\\n");\n        return 0;\n    }\n    if (tst == 0) {\n        if (!SSL_CTX_add_server_custom_ext(sctx, TEST_EXT_TYPE1, old_add_cb,\n                                           old_free_cb, &server, old_parse_cb,\n                                           &server)) {\n            printf("Unable to create old style server side custom extension\\n");\n            return 0;\n        }\n    } else {\n        if (!SSL_CTX_add_custom_ext(sctx, TEST_EXT_TYPE1, context, new_add_cb,\n                                    new_free_cb, &server, new_parse_cb,\n                                    &server)) {\n            printf("Unable to create new style server side custom extension\\n");\n            return 0;\n        }\n    }\n    if (SSL_CTX_add_server_custom_ext(sctx, TEST_EXT_TYPE1, old_add_cb,\n                                      old_free_cb, &server, old_parse_cb,\n                                      &server)) {\n        printf("Unexpected success adding duplicate server custom extension\\n");\n        return 0;\n    }\n    if (SSL_CTX_add_custom_ext(sctx, TEST_EXT_TYPE1, context, new_add_cb,\n                               new_free_cb, &server, new_parse_cb, &server)) {\n        printf("Unexpected success adding duplicate server custom extension\\n");\n        return 0;\n    }\n    if (!create_ssl_objects(sctx, cctx, &serverssl, &clientssl, NULL, NULL)) {\n        printf("Unable to create SSL objects\\n");\n        goto end;\n    }\n    if (!create_ssl_connection(serverssl, clientssl, SSL_ERROR_NONE)) {\n        printf("Unable to create SSL connection\\n");\n        goto end;\n    }\n    if (tst == 0) {\n        if (clntaddoldcb != 1 || clntparseoldcb != 1 || srvaddoldcb != 1\n                || srvparseoldcb != 1) {\n            printf("Custom extension callbacks not called\\n");\n            goto end;\n        }\n    } else if (tst == 1 || tst == 2) {\n        if (clntaddnewcb != 1 || clntparsenewcb != 1 || srvaddnewcb != 1\n                || srvparsenewcb != 1) {\n            printf("Custom extension callbacks not called\\n");\n            goto end;\n        }\n    } else {\n        if (clntaddnewcb != 1 || clntparsenewcb != 4 || srvaddnewcb != 4\n                || srvparsenewcb != 1) {\n            printf("Custom extension callbacks not called\\n");\n            goto end;\n        }\n    }\n    sess = SSL_get1_session(clientssl);\n    SSL_shutdown(clientssl);\n    SSL_shutdown(serverssl);\n    SSL_free(serverssl);\n    SSL_free(clientssl);\n    serverssl = clientssl = NULL;\n    if (!create_ssl_objects(sctx, cctx, &serverssl, &clientssl, NULL, NULL)) {\n        printf("Unable to create SSL objects (2)\\n");\n        goto end;\n    }\n    if (!SSL_set_session(clientssl, sess)) {\n        printf("Failed setting session\\n");\n        goto end;\n    }\n    if (!create_ssl_connection(serverssl, clientssl, SSL_ERROR_NONE)) {\n        printf("Unable to create SSL connection (2)\\n");\n        goto end;\n    }\n    if (tst == 0) {\n        if (clntaddoldcb != 2 || clntparseoldcb != 1 || srvaddoldcb != 1\n                || srvparseoldcb != 1) {\n            printf("Unexpected custom extension callback calls\\n");\n            goto end;\n        }\n    } else if (tst == 1 || tst == 2) {\n        if (clntaddnewcb != 2 || clntparsenewcb != 2 || srvaddnewcb != 2\n                || srvparsenewcb != 2) {\n            printf("Unexpected custom extension callback calls\\n");\n            goto end;\n        }\n    } else {\n        if (clntaddnewcb != 2 || clntparsenewcb != 7 || srvaddnewcb != 7\n                || srvparsenewcb != 2) {\n            printf("Unexpected custom extension callback calls\\n");\n            goto end;\n        }\n    }\n    testresult = 1;\nend:\n    SSL_SESSION_free(sess);\n    SSL_free(serverssl);\n    SSL_free(clientssl);\n    SSL_CTX_free(sctx);\n    SSL_CTX_free(cctx);\n    return testresult;\n}', 'int SSL_CTX_add_custom_ext(SSL_CTX *ctx, unsigned int ext_type,\n                           unsigned int context,\n                           SSL_custom_ext_add_cb_ex add_cb,\n                           SSL_custom_ext_free_cb_ex free_cb,\n                           void *add_arg,\n                           SSL_custom_ext_parse_cb_ex parse_cb, void *parse_arg)\n{\n    return add_custom_ext_intern(ctx, ENDPOINT_BOTH, ext_type, context, add_cb,\n                                 free_cb, add_arg, parse_cb, parse_arg);\n}', 'static int add_custom_ext_intern(SSL_CTX *ctx, ENDPOINT role,\n                                 unsigned int ext_type,\n                                 unsigned int context,\n                                 SSL_custom_ext_add_cb_ex add_cb,\n                                 SSL_custom_ext_free_cb_ex free_cb,\n                                 void *add_arg,\n                                 SSL_custom_ext_parse_cb_ex parse_cb,\n                                 void *parse_arg)\n{\n    custom_ext_methods *exts = &ctx->cert->custext;\n    custom_ext_method *meth, *tmp;\n    if (add_cb == NULL && free_cb != NULL)\n        return 0;\n#ifndef OPENSSL_NO_CT\n    if (ext_type == TLSEXT_TYPE_signed_certificate_timestamp\n            && (context & SSL_EXT_CLIENT_HELLO) != 0\n            && SSL_CTX_ct_is_enabled(ctx))\n        return 0;\n#endif\n    if (SSL_extension_supported(ext_type)\n            && ext_type != TLSEXT_TYPE_signed_certificate_timestamp)\n        return 0;\n    if (ext_type > 0xffff)\n        return 0;\n    if (custom_ext_find(exts, role, ext_type, NULL))\n        return 0;\n    tmp = OPENSSL_realloc(exts->meths,\n                          (exts->meths_count + 1) * sizeof(custom_ext_method));\n    if (tmp == NULL)\n        return 0;\n    exts->meths = tmp;\n    meth = exts->meths + exts->meths_count;\n    memset(meth, 0, sizeof(*meth));\n    meth->role = role;\n    meth->context = context;\n    meth->parse_cb = parse_cb;\n    meth->add_cb = add_cb;\n    meth->free_cb = free_cb;\n    meth->ext_type = ext_type;\n    meth->add_arg = add_arg;\n    meth->parse_arg = parse_arg;\n    exts->meths_count++;\n    return 1;\n}', 'custom_ext_method *custom_ext_find(const custom_ext_methods *exts,\n                                   ENDPOINT role, unsigned int ext_type,\n                                   size_t *idx)\n{\n    size_t i;\n    custom_ext_method *meth = exts->meths;\n    for (i = 0; i < exts->meths_count; i++, meth++) {\n        if (ext_type == meth->ext_type\n                && (role == ENDPOINT_BOTH || role == meth->role\n                    || meth->role == ENDPOINT_BOTH)) {\n            if (idx != NULL)\n                *idx = i;\n            return meth;\n        }\n    }\n    return NULL;\n}']