1SSL_ACCEPT(3)                       OpenSSL                      SSL_ACCEPT(3)
2
3
4

NAME

6       SSL_accept - wait for a TLS/SSL client to initiate a TLS/SSL handshake
7

SYNOPSIS

9        #include <openssl/ssl.h>
10
11        int SSL_accept(SSL *ssl);
12

DESCRIPTION

14       SSL_accept() waits for a TLS/SSL client to initiate the TLS/SSL
15       handshake.  The communication channel must already have been set and
16       assigned to the ssl by setting an underlying BIO.
17

NOTES

19       The behaviour of SSL_accept() depends on the underlying BIO.
20
21       If the underlying BIO is blocking, SSL_accept() will only return once
22       the handshake has been finished or an error occurred.
23
24       If the underlying BIO is nonblocking, SSL_accept() will also return
25       when the underlying BIO could not satisfy the needs of SSL_accept() to
26       continue the handshake, indicating the problem by the return value -1.
27       In this case a call to SSL_get_error() with the return value of
28       SSL_accept() will yield SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE.
29       The calling process then must repeat the call after taking appropriate
30       action to satisfy the needs of SSL_accept().  The action depends on the
31       underlying BIO. When using a nonblocking socket, nothing is to be done,
32       but select() can be used to check for the required condition. When
33       using a buffering BIO, like a BIO pair, data must be written into or
34       retrieved out of the BIO before being able to continue.
35

RETURN VALUES

37       The following return values can occur:
38
39       0   The TLS/SSL handshake was not successful but was shut down
40           controlled and by the specifications of the TLS/SSL protocol. Call
41           SSL_get_error() with the return value ret to find out the reason.
42
43       1   The TLS/SSL handshake was successfully completed, a TLS/SSL
44           connection has been established.
45
46       <0  The TLS/SSL handshake was not successful because a fatal error
47           occurred either at the protocol level or a connection failure
48           occurred. The shutdown was not clean. It can also occur if action
49           is needed to continue the operation for nonblocking BIOs. Call
50           SSL_get_error() with the return value ret to find out the reason.
51

SEE ALSO

53       SSL_get_error(3), SSL_connect(3), SSL_shutdown(3), ssl(7), bio(7),
54       SSL_set_connect_state(3), SSL_do_handshake(3), SSL_CTX_new(3)
55

57       Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
58
59       Licensed under the OpenSSL license (the "License").  You may not use
60       this file except in compliance with the License.  You can obtain a copy
61       in the file LICENSE in the source distribution or at
62       <https://www.openssl.org/source/license.html>.
63
64
65
661.1.1l                            2021-09-15                     SSL_ACCEPT(3)
Impressum