focal (3) cryptbuf.3bobcat.gz

NAME

       FBB::CryptBuf - std::streambuf derived base class for DecryptBuf and EncryptBuf

SYNOPSIS

       #include <bobcat/cryptbuf>
       Linking option: -lbobcat -lcrypto

DESCRIPTION

       The class CryptBuf inherits from EoiBuf and may therefore be used as a base class of classes specializing
       std::streambuf. It is used as base class for the classes DecryptBuf and EncryptBuf, offering a  protected
       member for accessing cipher information.

NAMESPACE

       FBB
       All  constructors,  members,  operators  and manipulators, mentioned in this man-page, are defined in the
       namespace FBB.

INHERITS FROM

       EoiBuf (and thus from: std::streambuf)

PROTECTED CONSTRUCTOR

       Analogously to std::streambuf only a protected constructor is available.

       o      CryptBuf(char const *type, size_t bufSize):
              The type is a null-terminated byte string specifying the de/encryption method. E.g.,  aes-128-cbc.
              For  an  overview  see the encryptbuf(3bobcat) man-page. The bufSize parameter defines the initial
              size of the internally used buffer (defined by EoiBuf).

       Copy and move constructors (and assignment operators) are not available.

PROTECTED MEMBER FUNCTION

       All members of std:streambuf and EoiBuf are available, as FBB::CryptBuf inherits from these classes.

       o      EVP_CIPHER const *md() const:
              A pointer to the cipher information is returned.

EXAMPLE

       Here is an example from the implementation of EncryptBuf’s constructor:

       #include "encryptbuf.ih"

       EncryptBuf::EncryptBuf(ostream &outStream, char const *type,
                              string key, string const &iv, size_t size)
       :
           CryptBuf(type, size),
           d_ctx(EVP_CIPHER_CTX_new()),
           d_encrypted(size + EVP_MAX_BLOCK_LENGTH, 0),
           d_iv(iv),
           d_key(key),
           d_outStream(outStream)
       {
           prepareIV();

           if (
               not EVP_EncryptInit_ex(d_ctx, md(), 0, ucharPtr(d_key),
                                                      ucharPtr(d_iv))
           )
               throw Exception{ 1 } << "Encrypt initialization failed";

           setp();
       }

FILES

       bobcat/cryptbuf - defines the class interface

SEE ALSO

       bobcat(7), decryptbuf(3bobcat), encryptbuf(3bobcat), eoibuf(3bobcat), eoi(3bobcat)

BUGS

       None Reported.

DISTRIBUTION FILES

       o      bobcat_5.02.00-x.dsc: detached signature;

       o      bobcat_5.02.00-x.tar.gz: source archive;

       o      bobcat_5.02.00-x_i386.changes: change log;

       o      libbobcat1_5.02.00-x_*.deb: debian package holding the libraries;

       o      libbobcat1-dev_5.02.00-x_*.deb: debian package holding the libraries, headers and manual pages;

       o      http://sourceforge.net/projects/bobcat: public archive location;

BOBCAT

       Bobcat is an acronym of `Brokken’s Own Base Classes And Templates’.

COPYRIGHT

       This is free software, distributed under the terms of the GNU General Public License (GPL).

AUTHOR

       Frank B. Brokken (f.b.brokken@rug.nl).