---
name: "SSL_set_incoming_stream_policy"
section: "3ssl"
platform: "linux"
package: "openssl"
version: "3.6.5-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/SSL_set_incoming_stream_policy"
---

# SSL\_set\_incoming\_stream\_policy(3ssl)

manage the QUIC incoming stream policy

## NAME

SSL\_set\_incoming\_stream\_policy, SSL\_INCOMING\_STREAM\_POLICY\_AUTO, SSL\_INCOMING\_STREAM\_POLICY\_ACCEPT, SSL\_INCOMING\_STREAM\_POLICY\_REJECT - manage the QUIC incoming stream policy

## SYNOPSIS

```
 #include <openssl/ssl.h>
 #define SSL_INCOMING_STREAM_POLICY_AUTO
 #define SSL_INCOMING_STREAM_POLICY_ACCEPT
 #define SSL_INCOMING_STREAM_POLICY_REJECT
 int SSL_set_incoming_stream_policy(SSL *conn, int policy,
                                           uint64_t app_error_code);
```

## DESCRIPTION

**SSL\_set\_incoming\_stream\_policy()** policy changes the incoming stream policy for a QUIC connection. Depending on the policy configured, OpenSSL QUIC may automatically reject incoming streams initiated by the peer. This is intended to ensure that legacy applications using single-stream operation with a default stream on a QUIC connection SSL object are not passed remotely-initiated streams by a peer which those applications are not prepared to handle.

*app\_error\_code* is an application error code which will be used in any QUIC **STOP\_SENDING** or **RESET\_STREAM** frames generated to implement the policy. The default application error code is 0.

The valid values for *policy* are:

- SSL\_INCOMING\_STREAM\_POLICY\_AUTO

  This is the default setting. Incoming streams are accepted according to the following rules:

  - •

    If the default stream mode (configured using **SSL\_set\_default\_stream\_mode**(3)) is set to **SSL\_DEFAULT\_STREAM\_MODE\_AUTO\_BIDI** (the default) or **SSL\_DEFAULT\_STREAM\_MODE\_AUTO\_UNI**, the incoming stream is rejected.

  - •

    Otherwise (where the default stream mode is **SSL\_DEFAULT\_STREAM\_MODE\_NONE**), the application is assumed to be stream aware, and the incoming stream is accepted.

- SSL\_INCOMING\_STREAM\_POLICY\_ACCEPT

  Always accept incoming streams, allowing them to be dequeued using **SSL\_accept\_stream**(3).

- SSL\_INCOMING\_STREAM\_POLICY\_REJECT

  Always reject incoming streams.

Where an incoming stream is rejected, it is rejected immediately and it is not possible to gain access to the stream using **SSL\_accept\_stream**(3). The stream is rejected using QUIC **STOP\_SENDING** and **RESET\_STREAM** frames as appropriate.

## RETURN VALUES

Returns 1 on success and 0 on failure.

This function fails if called on a QUIC stream SSL object, or on a non-QUIC SSL object.

## SEE ALSO

**SSL\_set\_default\_stream\_mode**(3), **SSL\_accept\_stream**(3)

## HISTORY

**SSL\_set\_incoming\_stream\_policy()** was added in OpenSSL 3.2.

## COPYRIGHT

Copyright 2002-2023 The OpenSSL Project Authors. 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\>.