1BIO_F_BASE64(3)                     OpenSSL                    BIO_F_BASE64(3)
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NAME

6       BIO_f_base64 - base64 BIO filter
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SYNOPSIS

9        #include <openssl/bio.h>
10        #include <openssl/evp.h>
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12        const BIO_METHOD *BIO_f_base64(void);
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DESCRIPTION

15       BIO_f_base64() returns the base64 BIO method. This is a filter BIO that
16       base64 encodes any data written through it and decodes any data read
17       through it.
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19       Base64 BIOs do not support BIO_gets() or BIO_puts().
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21       BIO_flush() on a base64 BIO that is being written through is used to
22       signal that no more data is to be encoded: this is used to flush the
23       final block through the BIO.
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25       The flag BIO_FLAGS_BASE64_NO_NL can be set with BIO_set_flags() to
26       encode the data all on one line or expect the data to be all on one
27       line.
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NOTES

30       Because of the format of base64 encoding the end of the encoded block
31       cannot always be reliably determined.
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RETURN VALUES

34       BIO_f_base64() returns the base64 BIO method.
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EXAMPLES

37       Base64 encode the string "Hello World\n" and write the result to
38       standard output:
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40        BIO *bio, *b64;
41        char message[] = "Hello World \n";
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43        b64 = BIO_new(BIO_f_base64());
44        bio = BIO_new_fp(stdout, BIO_NOCLOSE);
45        BIO_push(b64, bio);
46        BIO_write(b64, message, strlen(message));
47        BIO_flush(b64);
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49        BIO_free_all(b64);
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51       Read Base64 encoded data from standard input and write the decoded data
52       to standard output:
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54        BIO *bio, *b64, *bio_out;
55        char inbuf[512];
56        int inlen;
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58        b64 = BIO_new(BIO_f_base64());
59        bio = BIO_new_fp(stdin, BIO_NOCLOSE);
60        bio_out = BIO_new_fp(stdout, BIO_NOCLOSE);
61        BIO_push(b64, bio);
62        while ((inlen = BIO_read(b64, inbuf, 512)) > 0)
63            BIO_write(bio_out, inbuf, inlen);
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65        BIO_flush(bio_out);
66        BIO_free_all(b64);
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BUGS

69       The ambiguity of EOF in base64 encoded data can cause additional data
70       following the base64 encoded block to be misinterpreted.
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72       There should be some way of specifying a test that the BIO can perform
73       to reliably determine EOF (for example a MIME boundary).
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76       Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
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78       Licensed under the OpenSSL license (the "License").  You may not use
79       this file except in compliance with the License.  You can obtain a copy
80       in the file LICENSE in the source distribution or at
81       <https://www.openssl.org/source/license.html>.
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851.1.1                             2018-09-11                   BIO_F_BASE64(3)
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