SSL_CTX_set_mode, SSL_set_mode, SSL_CTX_get_mode, SSL_get_mode - manipulate SSL engine mode
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);
SSL_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.
The following mode changes are available:
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
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
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
behaves like non-blocking
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_set_mode() return the
new mode bitmask after adding mode.
SSL_get_mode() return the
ssl(3), SSL_read(3), SSL_write(3)
SSL_MODE_AUTO_RETRY as been added in OpenSSL 0.9.6.