f86035c65b
This format is described in [MS-XCA] 2.1 and 2.2, with exegesis in many posts on the cifs-protocol list[1]. The two public functions are: ssize_t lzxpress_huffman_decompress(const uint8_t *input, size_t input_size, uint8_t *output, size_t output_size); uint8_t *lzxpress_huffman_decompress_talloc(TALLOC_CTX *mem_ctx, const uint8_t *input_bytes, size_t input_size, size_t output_size); In both cases the caller needs to know the *exact* decompressed size, which is essential for decompression. The _talloc version allocates the buffer for you, and uses the talloc context to allocate a 128k working buffer. THe non-talloc function will allocate the working buffer on the stack. This compression format gives better compression for messages of several kilobytes than the "plain" LXZPRESS compression, but is probably a bit slower to decompress and is certainly worse for very short messages, having a fixed 256 byte overhead for the first Huffman table. Experiments show decompression rates between 20 and 500 MB per second, depending on the compression ratio and data size, on an i5-1135G7 with no compiler optimisations. This compression format is used in AD claims and in SMB, but that doesn't happen with this commit. I will not try to describe LZ77 or Huffman encoding here. Don't expect an answer in MS-XCA either; instead read the code and/or Wikipedia. [1] Much of that starts here: https://lists.samba.org/archive/cifs-protocol/2022-October/ but there's more earlier, particularly in June/July 2020, when Aurélien Aptel was working on an implementation that ended up in Wireshark. Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz> Pair-programmed-with: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz> |
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| auth | ||
| bootstrap | ||
| buildtools | ||
| coverity | ||
| ctdb | ||
| dfs_server | ||
| docs-xml | ||
| dynconfig | ||
| examples | ||
| file_server | ||
| include | ||
| lib | ||
| libcli | ||
| libds/common | ||
| libgpo | ||
| librpc | ||
| nsswitch | ||
| packaging | ||
| pidl | ||
| python | ||
| release-scripts | ||
| script | ||
| selftest | ||
| source3 | ||
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| testdata | ||
| testprogs | ||
| tests | ||
| testsuite | ||
| third_party | ||
| wintest | ||
| .bzrignore | ||
| .clang-format | ||
| .editorconfig | ||
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| .gitlab-ci-coverage-runners.yml | ||
| .gitlab-ci-coverage.yml | ||
| .gitlab-ci-default-runners.yml | ||
| .gitlab-ci-default.yml | ||
| .gitlab-ci-main.yml | ||
| .gitlab-ci-private.yml | ||
| .gitlab-ci.yml | ||
| .testr.conf | ||
| .ycm_extra_conf.py | ||
| callcatcher-exceptions.grep | ||
| configure | ||
| configure.developer | ||
| COPYING | ||
| GPG_AA99442FB680B620_replaces_6F33915B6568B7EA.txt | ||
| Makefile | ||
| PFIF.txt | ||
| README.cifs-utils | ||
| README.Coding.md | ||
| README.contributing | ||
| README.md | ||
| SECURITY.md | ||
| setup.cfg | ||
| VERSION | ||
| VFS-License-clarification.txt | ||
| WHATSNEW.txt | ||
| wscript | ||
| wscript_build | ||
| wscript_build_embedded_heimdal | ||
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| wscript_build_system_mitkrb5 | ||
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About Samba
Samba is the standard Windows interoperability suite of programs for Linux and Unix. Samba is Free Software licensed under the GNU General Public License and the Samba project is a member of the Software Freedom Conservancy. Since 1992, Samba has provided secure, stable and fast file and print services for all clients using the SMB/CIFS protocol, such as all versions of DOS and Windows, OS/2, Linux and many others. Samba is an important component to seamlessly integrate Linux/Unix Servers and Desktops into Active Directory environments. It can function both as a domain controller or as a regular domain member.
For the AD DC implementation a full HOWTO is provided at: https://wiki.samba.org/index.php/Samba4/HOWTO
Community guidelines can be read at: https://wiki.samba.org/index.php/How_to_do_Samba:_Nicely
This software is freely distributable under the GNU public license, a copy of which you should have received with this software (in a file called COPYING).
CONTRIBUTIONS
Please see https://wiki.samba.org/index.php/Contribute for detailed set-by-step instructions on how to submit a patch for Samba via GitLab.
Samba's GitLab mirror is at https://gitlab.com/samba-team/samba
OUR CONTRIBUTORS
See https://www.samba.org/samba/team/ for details of the Samba Team, as well as details of all those currently active in Samba development.
If you like a particular feature then look through the git change-log (on the web at https://gitweb.samba.org/?p=samba.git;a=summary) and see who added it, then send them an email.
Remember that free software of this kind lives or dies by the response we get. If no one tells us they like it then we'll probably move onto something else.
MORE INFO
DOCUMENTATION
There is quite a bit of documentation included with the package, including man pages and the wiki at https://wiki.samba.org
If you would like to help with our documentation, please contribute that improved content to the wiki, we are moving as much content there as possible.
MAILING LIST
Please do NOT send subscription/unsubscription requests to the lists!
There is a mailing list for discussion of Samba. For details go to https://lists.samba.org/ or send mail to samba-subscribe@lists.samba.org
There is also an announcement mailing list where new versions are announced. To subscribe go to https://lists.samba.org/ or send mail to samba-announce-subscribe@lists.samba.org. All announcements also go to the samba list, so you only need to be on one.
For details of other Samba mailing lists and for access to archives, see https://lists.samba.org/
MAILING LIST ETIQUETTE
A few tips when submitting to this or any mailing list.
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Make your subject short and descriptive. Avoid the words "help" or "Samba" in the subject. The readers of this list already know that a) you need help, and b) you are writing about samba (of course, you may need to distinguish between Samba PDC and other file sharing software). Avoid phrases such as "what is" and "how do i". Some good subject lines might look like "Slow response with Excel files" or "Migrating from Samba PDC to NT PDC".
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If you include the original message in your reply, trim it so that only the relevant lines, enough to establish context, are included. Chances are (since this is a mailing list) we've already read the original message.
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Trim irrelevant headers from the original message in your reply. All we need to see is a) From, b) Date, and c) Subject. We don't even really need the Subject, if you haven't changed it. Better yet is to just preface the original message with "On [date] [someone] wrote:".
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Please don't reply to or argue about spam, spam filters or viruses on any Samba lists. We do have a spam filtering system that is working quite well thank you very much but occasionally unwanted messages slip through. Deal with it.
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Never say "Me too." It doesn't help anyone solve the problem. Instead, if you ARE having the same problem, give more information. Have you seen something that the other writer hasn't mentioned, which may be helpful?
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If you ask about a problem, then come up with the solution on your own or through another source, by all means post it. Someone else may have the same problem and is waiting for an answer, but never hears of it.
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Give as much relevant information as possible such as Samba release number, OS, kernel version, etc...
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RTFM. Google.
WEBSITE
A Samba website has been setup with lots of useful info. Connect to:
As well as general information and documentation, this also has searchable archives of the mailing list and links to other useful resources such as the wiki.