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diff --git a/openssl/doc/crypto/BIO_f_cipher.pod b/openssl/doc/crypto/BIO_f_cipher.pod
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+++ b/openssl/doc/crypto/BIO_f_cipher.pod
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+=pod
+
+=head1 NAME
+
+BIO_f_cipher, BIO_set_cipher, BIO_get_cipher_status, BIO_get_cipher_ctx - cipher BIO filter
+
+=head1 SYNOPSIS
+
+ #include <openssl/bio.h>
+ #include <openssl/evp.h>
+
+ BIO_METHOD *	BIO_f_cipher(void);
+ void BIO_set_cipher(BIO *b,const EVP_CIPHER *cipher,
+		unsigned char *key, unsigned char *iv, int enc);
+ int BIO_get_cipher_status(BIO *b)
+ int BIO_get_cipher_ctx(BIO *b, EVP_CIPHER_CTX **pctx)
+
+=head1 DESCRIPTION
+
+BIO_f_cipher() returns the cipher BIO method. This is a filter
+BIO that encrypts any data written through it, and decrypts any data
+read from it. It is a BIO wrapper for the cipher routines
+EVP_CipherInit(), EVP_CipherUpdate() and EVP_CipherFinal().
+
+Cipher BIOs do not support BIO_gets() or BIO_puts(). 
+
+BIO_flush() on an encryption BIO that is being written through is
+used to signal that no more data is to be encrypted: this is used
+to flush and possibly pad the final block through the BIO.
+
+BIO_set_cipher() sets the cipher of BIO B<b> to B<cipher> using key B<key>
+and IV B<iv>. B<enc> should be set to 1 for encryption and zero for
+decryption.
+
+When reading from an encryption BIO the final block is automatically
+decrypted and checked when EOF is detected. BIO_get_cipher_status()
+is a BIO_ctrl() macro which can be called to determine whether the
+decryption operation was successful.
+
+BIO_get_cipher_ctx() is a BIO_ctrl() macro which retrieves the internal
+BIO cipher context. The retrieved context can be used in conjunction
+with the standard cipher routines to set it up. This is useful when
+BIO_set_cipher() is not flexible enough for the applications needs.
+
+=head1 NOTES
+
+When encrypting BIO_flush() B<must> be called to flush the final block
+through the BIO. If it is not then the final block will fail a subsequent
+decrypt.
+
+When decrypting an error on the final block is signalled by a zero
+return value from the read operation. A successful decrypt followed
+by EOF will also return zero for the final read. BIO_get_cipher_status()
+should be called to determine if the decrypt was successful.
+
+As always, if BIO_gets() or BIO_puts() support is needed then it can
+be achieved by preceding the cipher BIO with a buffering BIO.
+
+=head1 RETURN VALUES
+
+BIO_f_cipher() returns the cipher BIO method.
+
+BIO_set_cipher() does not return a value.
+
+BIO_get_cipher_status() returns 1 for a successful decrypt and 0
+for failure.
+
+BIO_get_cipher_ctx() currently always returns 1.
+
+=head1 EXAMPLES
+
+TBA
+
+=head1 SEE ALSO
+
+TBA