Commit ab874dfd authored by Matt Caswell's avatar Matt Caswell
Browse files

Clarify that SSL_shutdown() must not be called after a fatal error 

Follow on from CVE-2019-1559

Reviewed-by: default avatarRichard Levitte <levitte@openssl.org>
parent 72a7a702

doc/man3/SSL_get_error.pod

+8 −5
Changes for doc/man3/SSL_get_error.pod: 8 added lines, 5 removed lines.
Original line number Diff line number Diff line
@@ -138,17 +138,20 @@ Details depend on the application. 


=item SSL_ERROR_SYSCALL



Some non-recoverable I/O error occurred.

The OpenSSL error queue may contain more information on the error.

For socket I/O on Unix systems, consult B<errno> for details.

Some non-recoverable, fatal I/O error occurred. The OpenSSL error queue may

contain more information on the error. For socket I/O on Unix systems, consult

B<errno> for details. If this error occurs then no further I/O operations should

be performed on the connection and SSL_shutdown() must not be called.



This value can also be returned for other errors, check the error queue for

details.



=item SSL_ERROR_SSL



A failure in the SSL library occurred, usually a protocol error.  The

OpenSSL error queue contains more information on the error.

A non-recoverable, fatal error in the SSL library occurred, usually a protocol

error.  The OpenSSL error queue contains more information on the error. If this

error occurs then no further I/O operations should be performed on the

connection and SSL_shutdown() must not be called.



=back

doc/man3/SSL_shutdown.pod

+4 −0
Changes for doc/man3/SSL_shutdown.pod: 4 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -22,6 +22,10 @@ Whether the operation succeeds or not, the SSL_SENT_SHUTDOWN flag is set and 
a currently open session is considered closed and good and will be kept in the

session cache for further reuse.



Note that SSL_shutdown() must not be called if a previous fatal error has

occurred on a connection i.e. if SSL_get_error() has returned SSL_ERROR_SYSCALL

or SSL_ERROR_SSL.



The shutdown procedure consists of two steps: sending of the close_notify

shutdown alert, and reception of the peer's close_notify shutdown alert.

The order of those two steps depends on the application.