Rspamd is designed to process hundreds of messages per second simultaneously, and provides a number of
useful features.
-You can watch the following [introduction video](https://www.youtube.com/watch?v=_fl9i-az_Q0) from [FOSDEM-2016](http://fosdem.org) where I describe the main features of Rspamd and explain why Rspamd is so fast.
-
-Rspamd is [packaged](https://rspamd.com/downloads.html) for the major Linux distributions, and is also available via [FreeBSD ports](https://freshports.org/mail/rspamd), NetBSD [pkgsrc](https://pkgsrc.org) and [OpenBSD ports](http://openports.se/mail/rspamd).
-
-## Spam filtering features
-
-The Rspamd distribution contains a number of mail processing features, including such techniques as:
-
-* **Regular expressions filtering** - allows basic processing of messages, their textual parts, MIME headers and
-SMTP data received by MTA against a set of expressions that includes both normal regular expressions and
-message processing functions. Rspamd expressions are a powerful tool that allows to filter messages based on
-some pre-defined rules. This feature is similar to regular expressions in the SpamAssassin spam filter.
-
-
-* **SPF module** that allows to validate a message's sender against the policy defined in the DNS record of sender's domain. You can read
-about SPF policies [here](http://www.openspf.org/). A number of mail systems include SPF support, such as Gmail or Yahoo Mail.
-
-
-* **DKIM module** validates a message’s cryptographic signature against a public key placed in the DNS record of sender's domain. Like SPF,
-this technique is widely spread and allows to validate that a message is sent from that specific domain.
-
-
-* **DNS black lists** allows to estimate reputation of sender's IP address or network. Rspamd uses a number of DNS lists including such lists as
-`SORBS` or `Spamhaus`. However, Rspamd doesn't trust any specific DNS list and instead uses a conjunction of estimations that allows to
-avoid mistakes and false positives. Rspamd also uses positive and grey DNS lists for checking for trusted senders.
-
-
-* **URL black lists** are rather similar to DNS black lists but use URLs in a message to make an estimation of the sender's reputation.
-This technique is very useful for finding malicious or phished domains and filter E-mail that contains them.
-
-
-* **Statistics** - Rspamd uses a Bayesian classifier based on five-grams of input. This means that the input is estimated not based on individual
-words, but instead is organized in chains that are further estimated by the Bayesian classifier. This approach allows to achieve better results than
-traditionally used monograms (or words literally speaking), that are described in details in the following [paper](http://osbf-lua.luaforge.net/papers/osbf-eddc.pdf).
+## Getting Started
-* **Fuzzy hashes** - for checking of malicious mail patterns, Rspamd uses the so called "fuzzy hashes". Unlike normal hashes, these structures are targeted to hide
-the small differences between text patterns, allowing it to find similar messages quickly. Rspamd has an internal storage of such hashes and can block mass spam sendings
-quickly based on feedback from the user that specifies messages’ reputation. Moreover, this allows to feed Rspamd with data from ["honeypots"](http://en.wikipedia.org/wiki/Honeypot_(computing)#Spam_versions)
-without polluting the statistical module.
+A good starting point to study how to install and configure Rspamd is [the quick start guide](https://rspamd.com/doc/quickstart.html).
-Rspamd uses the conjunction of different techniques to assign the final verdict to a message. This allows to improve the overall quality of filtering, and reduce the number of
-false positives (e.g. when an innocent message is badly classified as a spam one). I have tried to simplify Rspamd’s usability by adding the following elements:
-
-* **Web interface** - Rspamd is shipped with a fully functional Ajax-based web interface, that allows one to observe Rspamd statistics, to configure rules, weights and lists, to scan
-and learn messages, and to view the history of scans. The interface is self-hosted, requires zero configuration and follows the recent web applications standards. You don't need a
-web server or applications server to run it - you just need to run Rspamd itself and a web browser.
-
-* **Integration with MTAs** - Rspamd can work with the most popular mail transfer systems, such as Postfix, Exim or Sendmail. Should you require MTA integration then please consult the [integration guide](https://rspamd.com/doc/integration.html).
-
-* **Extensive Lua API** - Rspamd ships with hundreds of [Lua functions](https://rspamd.com/doc/lua) that enable one to write their own rules for efficient and targeted spam filtering.
-
-* **Dynamic tables** - Rspamd allows one to specify bulk lists as "dynamic maps", that are checked at runtime for updated data. Rspamd supports file, HTTP and HTTPS maps.
-
-## Performance
-
-Rspamd is designed to be fast. The core of Rspamd is written in C and uses an event-driven model that allows it to process multiple messages simultaneously and without blocking.
-Moreover, a set of techniques is used in Rspamd to process messages faster:
-
-* **Finite state machines processing** - Rspamd uses specialized finite state machines for performance critical tasks to process input faster than a set of regular expressions.
-Of course, it is possible to implement these machines by ordinary Perl regular expressions, but then they won't be compact or human-readable. Instead, Rspamd optimizes
-such actions as headers processing, received elements extraction, and protocol operations by building the concrete automata for an assigned task.
-
-* **Expressions optimizer** - allows Rspamd to optimize expressions by execution of `likely false` or `likely true` expressions in order in the branches. That reduces a number of
-expensive expressions' calls when scanning a message.
-
-* **Symbols optimizer** - Rspamd tries to first evaluate the rules that are frequent or inexpensive in terms of time or CPU resources. This allows it to block spam before processing of
-expensive rules (rules with negative weights are always checked before other ones).
-
-* **Event driven model** - Rspamd is designed not to block anywhere in the code, and, given that a spam check requires a lot of network operations, Rspamd can process many messages
-simultaneously increasing the efficiency of shared DNS caches and other system resources. Moreover, event-driven system normally scales automatically and you won't need to do any
-tuning in the most of cases.
-
-* **Hyperscan regular expressions engine** - Rspamd utilizes the [Hyperscan](https://01.org/hyperscan) engine to match multiple regular expressions at the same time. You can read the following [presentation](https://highsecure.ru/rspamd-hyperscan.pdf) where the main benefits of Hyperscan are described.
-
-* **Clever choice of data structures** - Rspamd tries to use the optimal data structure for each task. For example, it uses very efficient suffix tries for fast matching of text
-against a set of multiple patterns. Or it uses a radix bit trie for storing IP addresses information that provides O(1) access time complexity.
-
-## Extensions
-
-Besides its C core, Rspamd provides an extensive [Lua](http://lua.org) API to access almost all the features available directly from C. Lua is an extremely easy
-to learn programming language though it is powerful enough to implement complex mail filters. In fact Rspamd has a significant amount of code written completely in Lua such as
-DNS blacklists checks, user's settings or different maps implementation. You can also write your own filters and rules in Lua adopting Rspamd functionality to your needs.
-Furthermore, Lua programs are very fast and their performance is rather [close](http://attractivechaos.github.io/plb/) to pure C. However, you should mention that for the most
-of performance critical tasks you usually use the Rspamd core functionality than Lua code. Anyway, you can also use LuaJIT with Rspamd if your goal is maximum performance.
-From the Lua API you can do the following tasks:
+Rspamd is [packaged](https://rspamd.com/downloads.html) for the major Linux distributions, and is also available via [FreeBSD ports](https://freshports.org/mail/rspamd), NetBSD [pkgsrc](https://pkgsrc.org) and [OpenBSD ports](http://openports.se/mail/rspamd).
-* **Reading the configuration parameters** - Lua code has the full access to the parsed configuration knobs and you can easily modify your plugins behaviour by means of the main
-Rspamd configuration.
+You can also watch some [videos about Rspamd](https://rspamd.com/media.html).
-* **Registering custom filters** - it is more than simple to add your own filters to Rspamd: just add new index to the global variable `rspamd_config`:
+## Spam filtering features
-~~~lua
-rspamd_config.MYFILTER = function(task)
--- Do something
-end
-~~~
+Rspamd is shipped with various spam filtering modules and features enabled just out of the box.
+The full list of built-in modules could be found in the [Rspamd documentation](https://rspamd.com/doc/modules/).
-* **Full access to the content of messages** - you can access text parts, headers, SMTP data and so on and so forth by using of `task` object. The full list of methods could be found
-[here](https://rspamd.com/doc/lua/task.html).
+If that is not enough, Rspamd provides an extensive [Lua API](https://rspamd.com/doc/lua/) to write your own rules and plugins: <https://rspamd.com/doc/tutorials/writing_rules.html>
+## Contributing
-* **Pre- and post- filters** - you can register callbacks that are called before or after messages processing to make results more precise or to make some early decision,
-for example, to implement a rate limit.
+Please read [CONTRIBUTIONS.md](https://github.com/rspamd/rspamd/blob/master/CONTRIBUTIONS.md) for details on the process for submitting pull requests to us.
-* **Registering functions for Rspamd** - you can write your own functions in Lua to extend Rspamd internal expression functions.
+## Authors
-* **Managing statistics** - Lua scripts can define a set of statistical files to be scanned or learned for a specific message allowing to create more complex
-statistical systems, e.g. based on an input language. Moreover, you can even learn Rspamd statistic from Lua scripts.
+* **Vsevolod Stakhov** - [vstakhov](https://github.com/vstakhov)
-* **Standalone Lua applications** - you can even write your own worker based on Rspamd core and performing some asynchronous logic in Lua. Of course, you can use the
-all features from Rspamd core, including such features as non-blocking IO, HTTP client and server, non-blocking Redis client, asynchronous DNS, UCL configuration and so on
-and so forth.
+See also the list of [contributors](https://github.com/rspamd/rspamd/AUTHORS.md) who participated in this project.
-* **API documentation** - Rspamd Lua API has an [extensive documentation](https://rspamd.com/doc/lua) where you can find examples, references and the guide about how to extend
-Rspamd with Lua.
+## License
+This project is licensed under the Apache 2.0 License - see the [LICENSE.md](LICENSE.md) file for details
## References
projects / rspamd.git / commitdiff