BIO_f_base64(3ssl)

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        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 stan‐
38       dard 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 = BIO_push(b64, bio);
46        BIO_write(bio, message, strlen(message));
47        BIO_flush(bio);
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49        BIO_free_all(bio);
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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 = BIO_push(b64, bio);
62        while((inlen = BIO_read(bio, inbuf, 512)) > 0)
63               BIO_write(bio_out, inbuf, inlen);
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65        BIO_free_all(bio);
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BUGS

68       The ambiguity of EOF in base64 encoded data can cause additional data
69       following the base64 encoded block to be misinterpreted.
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71       There should be some way of specifying a test that the BIO can perform
72       to reliably determine EOF (for example a MIME boundary).
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