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man pages section 3: Extended Library Functions, Volume 1

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Updated: Wednesday, July 27, 2022
 
 

BIO_f_base64 (3openssl)

Name

BIO_f_base64 - base64 BIO filter

Synopsis

#include <openssl/bio.h>
#include <openssl/evp.h>

BIO_METHOD *   BIO_f_base64(void);

Description

BIO_f_base64(3openssl)              OpenSSL             BIO_f_base64(3openssl)



NAME
       BIO_f_base64 - base64 BIO filter

SYNOPSIS
        #include <openssl/bio.h>
        #include <openssl/evp.h>

        BIO_METHOD *   BIO_f_base64(void);

DESCRIPTION
       BIO_f_base64() returns the base64 BIO method. This is a filter BIO that
       base64 encodes any data written through it and decodes any data read
       through it.

       Base64 BIOs do not support BIO_gets() or BIO_puts().

       BIO_flush() on a base64 BIO that is being written through is used to
       signal that no more data is to be encoded: this is used to flush the
       final block through the BIO.

       The flag BIO_FLAGS_BASE64_NO_NL can be set with BIO_set_flags() to
       encode the data all on one line or expect the data to be all on one
       line.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+--------------------------+
       |ATTRIBUTE TYPE |     ATTRIBUTE VALUE      |
       +---------------+--------------------------+
       |Availability   | library/security/openssl |
       +---------------+--------------------------+
       |Stability      | Pass-through uncommitted |
       +---------------+--------------------------+

NOTES
       Because of the format of base64 encoding the end of the encoded block
       cannot always be reliably determined.

       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       https://www.openssl.org/source/openssl-1.0.2ze.tar.gz.

       Further information about this software can be found on the open source
       community website at https://www.openssl.org/.

RETURN VALUES
       BIO_f_base64() returns the base64 BIO method.

EXAMPLES
       Base64 encode the string "Hello World\n" and write the result to
       standard output:

        BIO *bio, *b64;
        char message[] = "Hello World \n";

        b64 = BIO_new(BIO_f_base64());
        bio = BIO_new_fp(stdout, BIO_NOCLOSE);
        BIO_push(b64, bio);
        BIO_write(b64, message, strlen(message));
        BIO_flush(b64);

        BIO_free_all(b64);

       Read Base64 encoded data from standard input and write the decoded data
       to standard output:

        BIO *bio, *b64, *bio_out;
        char inbuf[512];
        int inlen;

        b64 = BIO_new(BIO_f_base64());
        bio = BIO_new_fp(stdin, BIO_NOCLOSE);
        bio_out = BIO_new_fp(stdout, BIO_NOCLOSE);
        BIO_push(b64, bio);
        while((inlen = BIO_read(b64, inbuf, 512)) > 0)
               BIO_write(bio_out, inbuf, inlen);

        BIO_flush(bio_out);
        BIO_free_all(b64);

BUGS
       The ambiguity of EOF in base64 encoded data can cause additional data
       following the base64 encoded block to be misinterpreted.

       There should be some way of specifying a test that the BIO can perform
       to reliably determine EOF (for example a MIME boundary).

SEE ALSO
       TBA




1.0.2ze                           2022-05-03            BIO_f_base64(3openssl)