SSL_CTX_set_mode(3) OpenSSL SSL_CTX_set_mode(3)NAME
SSL_CTX_set_mode, SSL_set_mode, SSL_CTX_get_mode, SSL_get_mode-
manipulate SSL engine mode
SYNOPSIS
#include <openssl/ssl.h>
long SSL_CTX_set_mode(SSL_CTX *ctx, long mode);
long SSL_set_mode(SSL *ssl, long mode);
long SSL_CTX_get_mode(SSL_CTX *ctx);
long SSL_get_mode(SSL *ssl);
DESCRIPTIONSSL_CTX_set_mode() adds the mode set via bitmask in mode to ctx.
Options already set before are not cleared.
SSL_set_mode() adds the mode set via bitmask in mode to ssl. Options
already set before are not cleared.
SSL_CTX_get_mode() returns the mode set for ctx.
SSL_get_mode() returns the mode set for ssl.
NOTES
The following mode changes are available:
SSL_MODE_ENABLE_PARTIAL_WRITE
Allow SSL_write(..., n) to return r with 0 < r < n (i.e. report
success when just a single record has been written). When not set
(the default), SSL_write() will only report success once the
complete chunk was written. Once SSL_write() returns with r, r
bytes have been successfully written and the next call to
SSL_write() must only send the n-r bytes left, imitating the
behaviour of write().
SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER
Make it possible to retry SSL_write() with changed buffer location
(the buffer contents must stay the same). This is not the default
to avoid the misconception that non-blocking SSL_write() behaves
like non-blocking write().
SSL_MODE_AUTO_RETRY
Never bother the application with retries if the transport is
blocking. If a renegotiation take place during normal operation, a
SSL_read(3) or SSL_write(3) would return with -1 and indicate the
need to retry with SSL_ERROR_WANT_READ. In a non-blocking
environment applications must be prepared to handle incomplete
read/write operations. In a blocking environment, applications are
not always prepared to deal with read/write operations returning
without success report. The flag SSL_MODE_AUTO_RETRY will cause
read/write operations to only return after the handshake and
successful completion.
SSL_MODE_RELEASE_BUFFERS
When we no longer need a read buffer or a write buffer for a given
SSL, then release the memory we were using to hold it. Released
memory is either appended to a list of unused RAM chunks on the
SSL_CTX, or simply freed if the list of unused chunks would become
longer than SSL_CTX->freelist_max_len, which defaults to 32. Using
this flag can save around 34k per idle SSL connection. This flag
has no effect on SSL v2 connections, or on DTLS connections.
RETURN VALUESSSL_CTX_set_mode() and SSL_set_mode() return the new mode bitmask after
adding mode.
SSL_CTX_get_mode() and SSL_get_mode() return the current bitmask.
SEE ALSOssl(3), SSL_read(3), SSL_write(3)HISTORY
SSL_MODE_AUTO_RETRY as been added in OpenSSL 0.9.6.
1.0.0j 2008-06-02 SSL_CTX_set_mode(3)