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In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
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Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright ©YEAR YOUR NAME. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts." line with this:
with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The licenses for most software are designed to take away your freedom to share
and change it. By contrast, the GNU General Public License is intended to
guarantee your freedom to share and change free software--to make sure the
software is free for all its users. This General Public License applies to
most of the Free Software Foundation's software and to any other program whose
authors commit to using it. (Some other Free Software Foundation software is
covered by the GNU Library General Public License instead.) You can apply it
to your programs, too.
When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it.
For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute and/or modify the software.
Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations.
Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone's free use or not licensed at all.
The precise terms and conditions for copying, distribution and modification follow.
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you".
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program (independent of having been made by running the Program). Whether that is true depends on what the Program does.
1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program.
You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.
2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:
These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program.
In addition, mere aggregation of another work not based on the Program with the Program (or with a work based on the Program) on a volume of a storage or distribution medium does not bring the other work under the scope of this License.
3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following:
The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable. However, as a special exception, the source code distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable.
If distribution of executable or object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place counts as distribution of the source code, even though third parties are not compelled to copy the source along with the object code.
4. You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense or distribute the Program is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.
5. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Program or its derivative works. These actions are prohibited by law if you do not accept this License. Therefore, by modifying or distributing the Program (or any work based on the Program), you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or modifying the Program or works based on it.
6. Each time you redistribute the Program (or any work based on the Program), the recipient automatically receives a license from the original licensor to copy, distribute or modify the Program subject to these terms and conditions. You may not impose any further restrictions on the recipients' exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties to this License.
7. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances.
It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice.
This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.
8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.
9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.
10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally.
NO WARRANTY
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found.
{\it one line to give the program's name and an idea of what it does.}
Copyright (C) {\it yyyy} {\it name of author}
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) {\it year} {\it name of author}
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
type `show w'. This is free software, and you are welcome
to redistribute it under certain conditions; type `show c'
for details.
The hypothetical commands `show w' and `show c' should show the
appropriate parts of the General Public License. Of course, the commands you
use may be called something other than `show w' and `show c'; they
could even be mouse-clicks or menu items--whatever suits your program.
You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright
interest in the program `Gnomovision'
(which makes passes at compilers) written
by James Hacker.
{\it signature of Ty Coon}, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License. Return to GNU's home page.
FSF & GNU inquiries & questions to gnu@gnu.org. Other ways to contact the FSF.
Comments on these web pages to webmasters@www.gnu.org, send other questions to gnu@gnu.org.
Copyright notice above. Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA
Updated: 3 Jan 2000 rms
image of a Philosophical GNU [ English | Japanese ]
This GNU Lesser General Public License counts as the successor of the GNU Library General Public License. For an explanation of why this change was necessary, read the Why you shouldn't use the Lesser GPL for your next library article.
Version 2.1, February 1999
Copyright (C) 1991, 1999 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. [This is the first released version of the Lesser GPL. It also counts as the successor of the GNU Library Public License, version 2, hence the version number 2.1.]
The licenses for most software are designed to take away your freedom to share
and change it. By contrast, the GNU General Public Licenses are intended to
guarantee your freedom to share and change free software--to make sure the
software is free for all its users.
This license, the Lesser General Public License, applies to some specially
designated software packages--typically libraries--of the Free Software
Foundation and other authors who decide to use it. You can use it too, but we
suggest you first think carefully about whether this license or the ordinary
General Public License is the better strategy to use in any particular case,
based on the explanations below.
When we speak of free software, we are referring to freedom of use, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish); that you receive source code or can get it if you want it; that you can change the software and use pieces of it in new free programs; and that you are informed that you can do these things.
To protect your rights, we need to make restrictions that forbid distributors to deny you these rights or to ask you to surrender these rights. These restrictions translate to certain responsibilities for you if you distribute copies of the library or if you modify it.
For example, if you distribute copies of the library, whether gratis or for a fee, you must give the recipients all the rights that we gave you. You must make sure that they, too, receive or can get the source code. If you link other code with the library, you must provide complete object files to the recipients, so that they can relink them with the library after making changes to the library and recompiling it. And you must show them these terms so they know their rights.
We protect your rights with a two-step method: (1) we copyright the library, and (2) we offer you this license, which gives you legal permission to copy, distribute and/or modify the library.
To protect each distributor, we want to make it very clear that there is no warranty for the free library. Also, if the library is modified by someone else and passed on, the recipients should know that what they have is not the original version, so that the original author's reputation will not be affected by problems that might be introduced by others.
Finally, software patents pose a constant threat to the existence of any free program. We wish to make sure that a company cannot effectively restrict the users of a free program by obtaining a restrictive license from a patent holder. Therefore, we insist that any patent license obtained for a version of the library must be consistent with the full freedom of use specified in this license.
Most GNU software, including some libraries, is covered by the ordinary GNU General Public License. This license, the GNU Lesser General Public License, applies to certain designated libraries, and is quite different from the ordinary General Public License. We use this license for certain libraries in order to permit linking those libraries into non-free programs.
When a program is linked with a library, whether statically or using a shared library, the combination of the two is legally speaking a combined work, a derivative of the original library. The ordinary General Public License therefore permits such linking only if the entire combination fits its criteria of freedom. The Lesser General Public License permits more lax criteria for linking other code with the library.
We call this license the "Lesser" General Public License because it does Less to protect the user's freedom than the ordinary General Public License. It also provides other free software developers Less of an advantage over competing non-free programs. These disadvantages are the reason we use the ordinary General Public License for many libraries. However, the Lesser license provides advantages in certain special circumstances.
For example, on rare occasions, there may be a special need to encourage the widest possible use of a certain library, so that it becomes a de-facto standard. To achieve this, non-free programs must be allowed to use the library. A more frequent case is that a free library does the same job as widely used non-free libraries. In this case, there is little to gain by limiting the free library to free software only, so we use the Lesser General Public License.
In other cases, permission to use a particular library in non-free programs enables a greater number of people to use a large body of free software. For example, permission to use the GNU C Library in non-free programs enables many more people to use the whole GNU operating system, as well as its variant, the GNU/Linux operating system.
Although the Lesser General Public License is Less protective of the users' freedom, it does ensure that the user of a program that is linked with the Library has the freedom and the wherewithal to run that program using a modified version of the Library.
The precise terms and conditions for copying, distribution and modification follow. Pay close attention to the difference between a "work based on the library" and a "work that uses the library". The former contains code derived from the library, whereas the latter must be combined with the library in order to run.
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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END OF TERMS AND CONDITIONS
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Copyright notice above. Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA
Updated: 27 Nov 2000 paulv
Once a new major version of Bacula is released, the Bacula users will vote on a list of new features. This vote is used as the main element determining what new features will be implemented for the next version. Generally, the development time for a new release is between 4 to 9 months.
For the current list of project, please see the projects page in the CVS at: http://cvs.sourceforge.net/viewcvs.py/*checkout*/bacula/bacula/projects see the projects file in the main source directory. The projects file is updated approximately once every six months.
Separately from the project list, Kern maintains a current list of tasks as well as ideas, feature requests, and occassionally design notes. This list is updated roughly weekly (sometimes more often). For a current list of tasks you can see kernstodo in the Source Forge CVS at http://cvs.sourceforge.net/viewcvs.py/*checkout*/bacula/bacula/kernstodo.
Thanks to Richard Stallman for starting the Free Software movement and for bringing us gcc and all the other GNU tools as well as the GPL license.
Thanks to Linus Torvalds for bringing us Linux.
Thanks to all the Free Software programmers. Without being able to peek at your code, and in some cases, take parts of it, this project would have been much more difficult.
Thanks to John Walker for suggesting this project, giving it a name, contributing software he has written, and for his programming efforts on Bacula as well as having acted as a constant sounding board and source of ideas.
Thanks to the apcupsd project where I started my Free Software efforts, and from which I was able to borrow some ideas and code that I had written.
Special thanks to D. Scott Barninger for writing the bacula RPM spec file, building all the RPM files and loading them onto Source Forge. This has been a tremendous help.
Many thanks to Karl Cunningham for converting the manual from html format to LaTeX. It was a major effort flawlessly done that will benefit the Bacula users for many years to come. Thanks Karl.
Thanks to Dan Langille for the incredible amount of testing he did on FreeBSD. His perseverance is truly remarkable. Thanks also for the many contributions he has made to improve Bacula (pthreads patch for FreeBSD, improved start/stop script and addition of Bacula userid and group, stunnel, ...), his continuing support of Bacula users. He also wrote the PostgreSQL driver for Bacula and has been a big help in correcting the SQL.
Thanks to multiple other Bacula Packagers who make and release packages for different platforms for Bacula.
Thanks to Christopher Hull for developing the native Win32 Bacula emulation code and for contributing it to the Bacula project.
Thanks to Thorsten Engel for his excellent knowledge of Win32 systems, and for making the Win32 File daemon Unicode compatible, as well as making the Win32 File daemon interface to Microsoft's Volume Shadow Copy (VSS). These two are big pluses for Bacula!
Thanks to Arno Lehmann for his excellent and infatigable help and advice to users.
Thanks to all the Bacula users, especially those of you who have contributed ideas, bug reports, patches, and new features.
Thanks to Nicolas Boichat for writing wx-console and the bacula-tray-monitor. These are very nice GUI additions to Bacula.
The original variable expansion code used in the LabelFormat comes from the Open Source Software Project (www.ossp.org). It has been adapted and extended for use in Bacula. This code is now deprecated.
There have been numerous people over the years who have contributed ideas, code, and help to the Bacula project. The file AUTHORS in the main source release file contains a list of contributors. For all those who I have left out, please send me a reminder, and in any case, thanks for your contribution.
Certain words and/or products are Copyrighted or Trademarked such as Windows (by Microsoft). Since they are numerous, and we are not necessarily aware of the details of each, we don't try to list them here. However, we acknowledge all such Copyrights and Trademarks, and if any copyright or trademark holder wishes a specific acknowledgment, notify us, and we will be happy to add it where appropriate.
Zum Glück gibt es in Bacula nicht sehr viele Programmfehler (Bugs), aber dank Dan Langille haben wir eine Bug-Datenbank, wo Fehler gemeldet werden können. Wenn ein Fehler behoben ist, wird normalerweise ein Programmstück das den Fehler korrigiert (Patch), auf der Seite des Fehlerberichts veröffentlicht.
Das Verzeichnis patches im aktuellen SVN enthält eine Liste aller Programmkorrekturen die für ältere Bacula-Versionen veröffentlicht wurden.
Eine "grobe" Übersicht der momentanen Arbeit und bekannter Probleme befindet sich auch in der Datei kernstodo im Hauptverzeichnis der Bacula-Programmquellen.
Please note that as of version 1.37, the Variable Expansion is deprecated and replaced by Python scripting (not yet documented).
Variable expansion is somewhat similar to Unix shell variable expansion. Currently (version 1.31), it is used only in format labels, but in the future, it will most likely be used in more places.
This is basically a string expansion capability that permits referencing variables, indexing arrays, conditional replacement of variables, case conversion, substring selection, regular expression matching and replacement, character class replacement, padding strings, repeated expansion in a user controlled loop, support of arithmetic expressions in the loop start, step and end conditions, and recursive expansion.
When using variable expansion characters in a Volume Label Format record, the format should always be enclosed in double quotes (").
For example, ${HOME} will be replaced by your home directory as defined in the environment. If you have defined the variable xxx to be Test, then the reference ${xxx:p/7/Y/r} will right pad the contents of xxx to a length of seven characters filling with the character Y giving YYYTest.
Within Bacula, there are three main classes of variables with some minor variations within the classes. The classes are:
Since the syntax is quite extensive, below, you will find the pseudo BNF. The special characters have the following meaning:
::= definition ( ) grouping if the parens are not quoted | separates alternatives '/' literal / (or any other character) CAPS a character or character sequence * preceding item can be repeated zero or more times ? preceding item can appear zero or one time + preceding item must appear one or more times
And the pseudo BNF describing the syntax is:
input ::= ( TEXT
| variable
| INDEX_OPEN input INDEX_CLOSE (loop_limits)?
)*
variable ::= DELIM_INIT (name|expression)
name ::= (NAME_CHARS)+
expression ::= DELIM_OPEN
(name|variable)+
(INDEX_OPEN num_exp INDEX_CLOSE)?
(':' command)*
DELIM_CLOSE
command ::= '-' (TEXT_EXP|variable)+
| '+' (TEXT_EXP|variable)+
| 'o' NUMBER ('-'|',') (NUMBER)?
| '#'
| '*' (TEXT_EXP|variable)+
| 's' '/' (TEXT_PATTERN)+
'/' (variable|TEXT_SUBST)*
'/' ('m'|'g'|'i'|'t')*
| 'y' '/' (variable|TEXT_SUBST)+
'/' (variable|TEXT_SUBST)*
'/'
| 'p' '/' NUMBER
'/' (variable|TEXT_SUBST)*
'/' ('r'|'l'|'c')
| '%' (name|variable)+
('(' (TEXT_ARGS)? ')')?
| 'l'
| 'u'
num_exp ::= operand
| operand ('+'|'-'|'*'|'/'|'%') num_exp
operand ::= ('+'|'-')? NUMBER
| INDEX_MARK
| '(' num_exp ')'
| variable
loop_limits ::= DELIM_OPEN
(num_exp)? ',' (num_exp)? (',' (num_exp)?)?
DELIM_CLOSE
NUMBER ::= ('0'|...|'9')+
TEXT_PATTERN::= (^('/'))+
TEXT_SUBST ::= (^(DELIM_INIT|'/'))+
TEXT_ARGS ::= (^(DELIM_INIT|')'))+
TEXT_EXP ::= (^(DELIM_INIT|DELIM_CLOSE|':'|'+'))+
TEXT ::= (^(DELIM_INIT|INDEX_OPEN|INDEX_CLOSE))+
DELIM_INIT ::= '$'
DELIM_OPEN ::= '{'
DELIM_CLOSE ::= '}'
INDEX_OPEN ::= '['
INDEX_CLOSE ::= ']'
INDEX_MARK ::= '#'
NAME_CHARS ::= 'a'|...|'z'|'A'|...|'Z'|'0'|...|'9'
The items listed in command above, which always follow a colon (:) have the following meanings:
- perform substitution if variable is empty
+ perform substitution if variable is not empty
o cut out substring of the variable value
# length of the variable value
* substitute empty string if the variable value is not empty,
otherwise substitute the trailing parameter
s regular expression search and replace. The trailing
options are: m = multiline, i = case insensitive,
g = global, t = plain text (no regexp)
y transpose characters from class A to class B
p pad variable to l = left, r = right or c = center,
with second value.
% special function call (none implemented)
l lower case the variable value
u upper case the variable value
The loop_limits are start, step, and end values.
A counter variable name followed immediately by a plus (+) will cause the counter to be incremented by one.
To create an ISO date:
DLT-${Year}-${Month:p/2/0/r}-${Day:p/2/0/r}
on 20 June 2003 would give DLT-2003-06-20
If you set the environment variable mon to
January|February|March|April|May|...
File-${mon[${Month}]}/${Day}/${Year}
on the first of March would give File-March/1/2003
Prior to version 1.37, Bacula did not have built-in communications encryption. Please see the TLS chapter if you are using Bacula 1.37 or greater.
Without too much effort, it is possible to encrypt the communications between any of the daemons. This chapter will show you how to use stunnel to encrypt communications to your client programs. We assume the Director and the Storage daemon are running on one machine that will be called server and the Client or File daemon is running on a different machine called client. Although the details may be slightly different, the same principles apply whether you are encrypting between Unix, Linux, or Win32 machines. This example was developed between two Linux machines running stunnel version 4.04-4 on a Red Hat Enterprise 3.0 system.
First, you must know that with the standard Bacula configuration, the Director will contact the File daemon on port 9102. The File daemon then contacts the Storage daemon using the address and port parameters supplied by the Director. The standard port used will be 9103. This is the typical server/client view of the world, the File daemon is a server to the Director (i.e. listens for the Director to contact it), and the Storage daemon is a server to the File daemon.
The encryption is accomplished between the Director and the File daemon by using an stunnel on the Director's machine (server) to encrypt the data and to contact an stunnel on the File daemon's machine (client), which decrypts the data and passes it to the client.
Between the File daemon and the Storage daemon, we use an stunnel on the File daemon's machine to encrypt the data and another stunnel on the Storage daemon's machine to decrypt the data.
As a consequence, there are actually four copies of stunnel running, two on the server and two on the client. This may sound a bit complicated, but it really isn't. To accomplish this, we will need to construct four separate conf files for stunnel, and we will need to make some minor modifications to the Director's conf file. None of the other conf files need to be changed.
Since pictures usually help a lot, here is an overview of what we will be doing. Don't worry about all the details of the port numbers and such for the moment.
File daemon (client):
stunnel-fd1.conf
|===========|
Port 29102 >----| Stunnel 1 |-----> Port 9102
|===========|
stunnel-fd2.conf
|===========|
Port 9103 >----| Stunnel 2 |-----> server:29103
|===========|
Director (server):
stunnel-dir.conf
|===========|
Port 29102 >----| Stunnel 3 |-----> client:29102
|===========|
stunnel-sd.conf
|===========|
Port 29103 >----| Stunnel 4 |-----> 9103
|===========|
In order for stunnel to function as a server, which it does in our diagram for Stunnel 1 and Stunnel 4, you must have a certificate and the key. It is possible to keep the two in separate files, but normally, you keep them in one single .pem file. You may create this certificate yourself in which case, it will be self-signed, or you may have it signed by a CA.
If you want your clients to verify that the server is in fact valid (Stunnel 2 and Stunnel 3), you will need to have the server certificates signed by a CA (Certificate Authority), and you will need to have the CA's public certificate (contains the CA's public key).
Having a CA signed certificate is highly recommended if you are using your client across the Internet, otherwise you are exposed to the man in the middle attack and hence loss of your data.
See below for how to create a self-signed certificate.
To simplify things a bit, let's for the moment consider only the data channel. That is the connection between the File daemon and the Storage daemon, which takes place on port 9103. In fact, in a minimalist solution, this is the only connection that needs to be encrypted, because it is the one that transports your data. The connection between the Director and the File daemon is simply a control channel used to start the job and get the job status.
Normally the File daemon will contact the Storage daemon on port 9103 (supplied by the Director), so we need an stunnel that listens on port 9103 on the File daemon's machine, encrypts the data and sends it to the Storage daemon. This is depicted by Stunnel 2 above. Note that this stunnel is listening on port 9103 and sending to server:29103. We use port 29103 on the server because if we would send the data to port 9103, it would go directly to the Storage daemon, which doesn't understand encrypted data. On the server machine, we run Stunnel 4, which listens on port 29103, decrypts the data and sends it to the Storage daemon, which is listening on port 9103.
The Storage resource of the bacula-dir.conf normally looks something like the following:
Storage {
Name = File
Address = server
SDPort = 9103
Password = storage_password
Device = File
Media Type = File
}
Notice that this is running on the server machine, and it points the File daemon back to server:9103, which is where our Storage daemon is listening. We modify this to be:
Storage {
Name = File
Address = localhost
SDPort = 9103
Password = storage_password
Device = File
Media Type = File
}
This causes the File daemon to send the data to the stunnel running on localhost (the client machine). We could have used client as the address as well.
In the diagram above, we see above Stunnel 2 that we use stunnel-fd2.conf on the client. A pretty much minimal config file would look like the following:
client = yes [29103] accept = localhost:9103 connect = server:29103
The above config file does encrypt the data but it does not require a certificate, so it is subject to the man in the middle attack. The file I actually used, stunnel-fd2.conf, looked like this:
# # Stunnel conf for Bacula client -> SD # pid = /home/kern/bacula/bin/working/stunnel.pid # # A cert is not mandatory here. If verify=2, a # cert signed by a CA must be specified, and # either CAfile or CApath must point to the CA's # cert # cert = /home/kern/stunnel/stunnel.pem CAfile = /home/kern/ssl/cacert.pem verify = 2 client = yes # debug = 7 # foreground = yes [29103] accept = localhost:9103 connect = server:29103
You will notice that I specified a pid file location because I ran stunnel under my own userid so I could not use the default, which requires root permission. I also specified a certificate that I have as well as verify level 2 so that the certificate is required and verified, and I must supply the location of the CA (Certificate Authority) certificate so that the stunnel certificate can be verified. Finally, you will see that there are two lines commented out, which when enabled, produce a lot of nice debug info in the command window.
If you do not have a signed certificate (stunnel.pem), you need to delete the cert, CAfile, and verify lines.
Note that the stunnel.pem, is actually a private key and a certificate in a single file. These two can be kept and specified individually, but keeping them in one file is more convenient.
The config file, stunnel-sd.conf, needed for Stunnel 4 on the server machine is:
# # Bacula stunnel conf for Storage daemon # pid = /home/kern/bacula/bin/working/stunnel.pid # # A cert is mandatory here, it may be self signed # If it is self signed, the client may not use # verify # cert = /home/kern/stunnel/stunnel.pem client = no # debug = 7 # foreground = yes [29103] accept = 29103 connect = 9103
It will most likely be the simplest to implement the Data Channel encryption in the following order:
stunnel stunnel-sd.conf
stunnel stunnel-fd2.conf
The Job control channel is between the Director and the File daemon, and as mentioned above, it is not really necessary to encrypt, but it is good practice to encrypt it as well. The two stunnels that are used in this case will be Stunnel 1 and Stunnel 3 in the diagram above. Stunnel 3 on the server might normally listen on port 9102, but if you have a local File daemon, this will not work, so we make it listen on port 29102. It then sends the data to client:29102. Again we use port 29102 so that the stunnel on the client machine can decrypt the data before passing it on to port 9102 where the File daemon is listening.
We need to modify the standard Client resource, which would normally look something like:
Client {
Name = client-fd
Address = client
FDPort = 9102
Catalog = BackupDB
Password = "xxx"
}
to be:
Client {
Name = client-fd
Address = localhost
FDPort = 29102
Catalog = BackupDB
Password = "xxx"
}
This will cause the Director to send the control information to localhost:29102 instead of directly to the client.
The stunnel config file, stunnel-dir.conf, for the Director's machine would look like the following:
# # Bacula stunnel conf for the Directory to contact a client # pid = /home/kern/bacula/bin/working/stunnel.pid # # A cert is not mandatory here. If verify=2, a # cert signed by a CA must be specified, and # either CAfile or CApath must point to the CA's # cert # cert = /home/kern/stunnel/stunnel.pem CAfile = /home/kern/ssl/cacert.pem verify = 2 client = yes # debug = 7 # foreground = yes [29102] accept = localhost:29102 connect = client:29102
and the config file, stunnel-fd1.conf, needed to run stunnel on the Client would be:
# # Bacula stunnel conf for the Directory to contact a client # pid = /home/kern/bacula/bin/working/stunnel.pid # # A cert is not mandatory here. If verify=2, a # cert signed by a CA must be specified, and # either CAfile or CApath must point to the CA's # cert # cert = /home/kern/stunnel/stunnel.pem CAfile = /home/kern/ssl/cacert.pem verify = 2 client = yes # debug = 7 # foreground = yes [29102] accept = localhost:29102 connect = client:29102
It will most likely be the simplest to implement the Control Channel encryption in the following order:
stunnel stunnel-dir.conf
stunnel stunnel-fd1.conf
On the client machine, you can just duplicate the setup that you have on the first client file for file and it should work fine.
In the bacula-dir.conf file, you will want to create a second client pretty much identical to how you did for the first one, but the port number must be unique. We previously used:
Client {
Name = client-fd
Address = localhost
FDPort = 29102
Catalog = BackupDB
Password = "xxx"
}
so for the second client, we will, of course, have a different name, and we will also need a different port. Remember that we used port 29103 for the Storage daemon, so for the second client, we can use port 29104, and the Client resource would look like:
Client {
Name = client2-fd
Address = localhost
FDPort = 29104
Catalog = BackupDB
Password = "yyy"
}
Now, fortunately, we do not need a third stunnel to on the Director's machine, we can just add the new port to the config file, stunnel-dir.conf, to make:
# # Bacula stunnel conf for the Directory to contact a client # pid = /home/kern/bacula/bin/working/stunnel.pid # # A cert is not mandatory here. If verify=2, a # cert signed by a CA must be specified, and # either CAfile or CApath must point to the CA's # cert # cert = /home/kern/stunnel/stunnel.pem CAfile = /home/kern/ssl/cacert.pem verify = 2 client = yes # debug = 7 # foreground = yes [29102] accept = localhost:29102 connect = client:29102 [29104] accept = localhost:29102 connect = client2:29102
There are no changes necessary to the Storage daemon or the other stunnel so that this new client can talk to our Storage daemon.
You may create a self-signed certificate for use with stunnel that will permit you to make it function, but will not allow certificate validation. The .pem file containing both the certificate and the key can be made with the following, which I put in a file named makepem:
#!/bin/sh
#
# Simple shell script to make a .pem file that can be used
# with stunnel and Bacula
#
OPENSSL=openssl
umask 77
PEM1="/bin/mktemp openssl.XXXXXX"
PEM2="/bin/mktemp openssl.XXXXXX"
${OPENSSL} req -newkey rsa:1024 -keyout $PEM1 -nodes \
-x509 -days 365 -out $PEM2
cat $PEM1 > stunnel.pem
echo "" >>stunnel.pem
cat $PEM2 >>stunnel.pem
rm $PEM1 $PEM2
The above script will ask you a number of questions. You may simply answer each of them by entering a return, or if you wish you may enter your own data.
The process of getting a certificate that is signed by a CA is quite a bit more complicated. You can purchase one from quite a number of PKI vendors, but that is not at all necessary for use with Bacula.
To get a CA signed certificate, you will either need to find a friend that has setup his own CA or to become a CA yourself, and thus you can sign all your own certificates. The book OpenSSL by John Viega, Matt Mesier & Pravir Chandra from O'Reilly explains how to do it, or you can read the documentation provided in the Open-source PKI Book project at Source Forge: http://ospkibook.sourceforge.net/docs/OSPKI-2.4.7/OSPKI-html/ospki-book.htm. Note, this link may change.
Please see the script ssh-tunnel.sh in the examples directory. It was contributed by Stephan Holl.