BIO(7SSL) - Linux man page online | Overview, conventions, and miscellany
Basic I/O abstraction.
BIO(7SSL) OpenSSL BIO(7SSL)
1.1.1 2020-05-27 BIO(7SSL)
NAMEbio - Basic I/O abstraction
DESCRIPTIONA BIO is an I/O abstraction, it hides many of the underlying I/O details from an application. If an application uses a BIO for its I/O it can transparently handle SSL connections, unencrypted network connections and file I/O. There are two type of BIO, a source/sink BIO and a filter BIO. As its name implies a source/sink BIO is a source and/or sink of data, examples include a socket BIO and a file BIO. A filter BIO takes data from one BIO and passes it through to another, or the application. The data may be left unmodified (for example a message digest BIO) or translated (for example an encryption BIO). The effect of a filter BIO may change according to the I/O operation it is performing: for example an encryption BIO will encrypt data if it is being written to and decrypt data if it is being read from. BIOs can be joined together to form a chain (a single BIO is a chain with one component). A chain normally consist of one source/sink BIO and one or more filter BIOs. Data read from or written to the first BIO then traverses the chain to the end (normally a source/sink BIO). Some BIOs (such as memory BIOs) can be used immediately after calling BIO_new(). Others (such as file BIOs) need some additional initialization, and frequently a utility function exists to create and initialize such BIOs. If BIO_free() is called on a BIO chain it will only free one BIO resulting in a memory leak. Calling BIO_free_all() on a single BIO has the same effect as calling BIO_free() on it other than the discarded return value. Normally the type argument is supplied by a function which returns a pointer to a BIO_METHOD. There is a naming convention for such functions: a source/sink BIO is normally called BIO_s_*() and a filter BIO BIO_f_*();
EXAMPLECreate a memory BIO: BIO *mem = BIO_new(BIO_s_mem());
SEE ALSOBIO_ctrl(3), BIO_f_base64(3), BIO_f_buffer(3), BIO_f_cipher(3), BIO_f_md(3), BIO_f_null(3), BIO_f_ssl(3), BIO_find_type(3), BIO_new(3), BIO_new_bio_pair(3), BIO_push(3), BIO_read_ex(3), BIO_s_accept(3), BIO_s_bio(3), BIO_s_connect(3), BIO_s_fd(3), BIO_s_file(3), BIO_s_mem(3), BIO_s_null(3), BIO_s_socket(3), BIO_set_callback(3), BIO_should_retry(3)
COPYRIGHTCopyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (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>.
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|bio(7ssl)||referred by||BIO_f_buffer(3ssl) | BIO_s_bio(3ssl) | BUF_MEM_new(3ssl) | DTLSv1_listen(3ssl) | OPENSSL_LH_stats(3ssl) | SCT_print(3ssl) | SSL_accept(3ssl) | SSL_connect(3ssl) | SSL_do_handshake(3ssl) | SSL_get_fd(3ssl) | SSL_get_rbio(3ssl) | SSL_read(3ssl) | SSL_set_bio(3ssl) | SSL_set_fd(3ssl) | SSL_shutdown(3ssl) | SSL_write(3ssl)|
BIO_ctrl(3ssl) | BIO_f_base64(3ssl) | BIO_f_buffer(3ssl) | BIO_f_cipher(3ssl) | BIO_f_md(3ssl) | BIO_f_null(3ssl) | BIO_f_ssl(3ssl) | BIO_find_type(3ssl) | BIO_new(3ssl) | BIO_push(3ssl) | BIO_read(3ssl) | BIO_s_accept(3ssl) | BIO_s_bio(3ssl) | BIO_s_connect(3ssl) | BIO_s_fd(3ssl) | BIO_s_file(3ssl) | BIO_s_mem(3ssl) | BIO_s_null(3ssl) | BIO_s_socket(3ssl) | BIO_set_callback(3ssl)