Rspamd 3.0 has been released

19 Aug 2021

We have released Rspamd 3.0 today. The decision to increase the major version number was taken because of the significant changes in the internal architecture Rspamd in many parts, specifically (but not limited) related to the HTML parsing. Rspamd now includes a CSS parser that can deal with the modern emails and properly extract data from them. New code is now written not in Plain C but in C++17 (might be extended to C++20 in future). Hence, to build Rspamd from the source code one would need a C++17 compatible compiler. This release includes contributions from many people, but I would like to say special thanks to the following persons:

  • Anton Yuzhaninov for testing Rspamd and being patient when dealing with the bugs, as well as for the valuable feedback on almost all questions
  • Andrew Lewis for constant work on Lua plugins and suggestions about Rspamd architecture
  • Alexander Moisseev for WebUI support and rules testing

Here are the most important changes in this version explained.

Main changes

HTML parser rework

Rspamd now parses HTML using a DOM model, so it can build and construct a parsed tree of HTML tags instead of a simple ad-hoc parsing. Adding this feature was quite untrivial, as it required full rewrite of the HTML related code. However, we can see that the new parser can deal with emails in HTML format that were completely ruined by a previous parser. Furthermore, better representation of HTML could lead to more sophisticated rules that take HTML structure into account.

CSS parser

Rspamd now has an embedded CSS parser that is currently limited to simple selectors but it could be extended in future. In conjunction with the modern HTML parser, CSS support is very valuable to extract the content from emails and distinguish visible and invisible content precisely.

Amazon S3 support

Rspamd now includes AWS API support (e.g. their signatures schema) which allows to interact with Amazon cloud services directly from Lua API. A simple plugin that stores all messages in AWS S3 cloud has also been written.

DMARC reporting rework

Rspamd DMARC reporting has proven to be troublesome in the previous version. Therefore, I have decided to move reports sending logic to a dedicated tool called rspamadm dmarc_report. The usage of this tool and DMARC reports in principle is already documented.

DMARC munging support

From version 3.0, Rspamd supports DMARC munging for the mailing list. In this mode, Rspamd will change the From: header to some pre-defined address (e.g. a mailing list address) for those messages who have valid DMARC policy with reject/quarantine that would otherwise fail during mailing list forwarding. An example of this technique is defined here.

External relay plugin

Many plugins, such as SPF, are using IP address provided by an MTA to Rspamd directly. However, in many cases there is a trusted relay that do some initial processing and hides the actual sender’s IP address. With help of this new plugin, Rspamd can now ‘fix’ this issue by treating sender’s IP as it is reported by that trusted relay.

Bayes export tool

Rspamd now allows to save and restore bayes tokens using rspamadm bayes_dump subcommand. This feature allows to move tokens between instances of Rspamd, to merge them and to analyse them manually.

Pyzor support

Rspamd now supports Pyzor via external services plugin, thanks to @defkev for this work!

Monitoring rework

Monitoring tools are now awaken less frequently reducing load on the external modules.

Other fixes and improvements

Core and API

  • Fixed retries on broken maps servers
  • Fixed handling of spaces in MIME From domains
  • Fixed handling of invalid IDN domains containing 8-bit characters
  • Fixed if..else..elseif handling in Lupa templates

Plugins

  • Neural: fixed profile filtering (offline) & unwanted retraining (online)
  • Fixed escaping in Clickhouse plugin
  • Fixed missing config schema & reconfigurability in RBL plugin (disabling RBLs; selectors)

Rules

  • Fixed CTYPE_MIXED_BOGUS for text attachments
  • Fixed PCRE-mode handling of BITCOIN_ADDR rule
  • Fixed REPLYTO_ADDR_EQ_FROM for normalised addresses

### Controller

  • OpenMetrics-compatible controller endpoint (@mrueg)
  • Health and readiness endpoints for Kubernetes (@mrueg)

All changes

Here is the list of the important changes:

  • [Conf] Align ARC scores with DKIM scores
  • [CritFix] Neural: Fix sorting application
  • [Feature] Add a simple dumper for bayes tokens
  • [Feature] Add lua_maps.fill_config_maps function
  • [Feature] Add preliminary exporter to AWS S3
  • [Feature] Add preliminary restore bayes support
  • [Feature] Add race condition protection against hs_helper restarts
  • [Feature] Add rspamd_utf8_strcmp utility
  • [Feature] Add zstd streaming API
  • [Feature] Allow to log severity level explicitly
  • [Feature] Allow to save and show attachment name when inserting AV scan results
  • [Feature] Allow to sort urls for Lua
  • [Feature] Allow to specify different timeouts/retransmits for fuzzy rules
  • [Feature] Aws_s3: Allow to compress data stored
  • [Feature] CMakeLists.txt: Change check and run-test to use rspamd-test-cxx * fixes #3807
  • [Feature] Dmarc_report: allow sending reports in batches
  • [Feature] Fuzzy_check: Allow to disable subject when making short text hash
  • [Feature] Lua_cryptobox: Add keyed ssl hash functions via HMAC
  • [Feature] Lua_task: Add get_urls_filtered method
  • [Feature] Make monitored checks less frequent
  • [Feature] Milter_headers: Add x-rspamd-pre-result header
  • [Feature] Neural: Allow to balance FP/FN for the network
  • [Feature] Ppopagate monitored errors from rbl module
  • [Feature] Pyzor calculate score dynamically Count - WL-Count of default_score in percent
  • [Feature] Rbl: Distinguish flattened and non-flattened selectors in RBL requests
  • [Feature] Re-add pyzor support
  • [Feature] Settings: add ip_map check and rework structure slightly
  • [Feature] Spamassassin: Allow to set the default priority for SA scores
  • [Feature] Strip smtp comments from message id
  • [Feature] add SYSTEM_ZSTD cmake option To use the system zstd instead on the bundled version
  • [Feature] external_relay plugin
  • [Feature] rspamadm clickhouse neural_train subcommand
  • Fix #3400 milter_headers: fix inverted logic for extended_headers_rcpt
  • Fix ASN: fix _FAIL symbol for when main symbol is disabled
  • Fix Add a special logic for text part with no text extraction
  • Fix Add diacritics flag for several eu languages
  • Fix Another FSM fix to accomodate possibility of multiple consequent ?
  • Fix Avoid curse of dynamic array referencing
  • Fix Avoid reinitialising neural settings
  • Fix Check remain before processing TXT records
  • Fix Enable error multiplier on http errors
  • Fix Finally rework parsing entities logic
  • Fix Fix ‘==’ parsing in the content type attributes parser
  • Fix Fix IPv6 expansion for SPF macros
  • Fix Fix Mozilla Message-ID detection
  • Fix Fix an edge case in BITCOIN_ADDR rule
  • Fix Fix brain-damaged behaviour when http request has a custom Host header
  • Fix Fix check of limits in email address parsing
  • Fix Fix copy&paste error and rework
  • Fix Fix expressions logic for and/or and float values
  • Fix Fix fuzzy retransmits
  • Fix Fix http maps with no or invalid expires data
  • Fix Fix last quote character parsing in the content-type state machine
  • Fix Fix normalisation flags propagation
  • Fix Fix overflow when appending many broken tags
  • Fix Fix parsing of rfc2047 tokens with ‘?’ inside
  • Fix Fix phishing flag set
  • Fix Fix rfc2047 embedded into rfc2231 pieces in special headers
  • Fix Fix round-robin rotation
  • Fix Fix searching for symbols
  • Fix Fix storing of the regexps inside variant
  • Fix Fix tokenization near exceptions
  • Fix Fix visibility calculations
  • Fix Html: Attach inline tags to the structure
  • Fix Html: Do not treat empty tags as block tags
  • Fix Ical: Do not extract urls from all flags using merely specific ones
  • Fix Initialise symcache even if it cannot be loaded properly
  • Fix Lua_fuzzy: Remove text parts check when checking image dimensions
  • Fix Lua_maps: Fix adjustments for the map type in the complex map definitions
  • Fix Lua_task: Fix deleted symbols in has_symbol/get_symbol
  • Fix Move metric and symcache link from validation to the init stage
  • Fix Oletools: Another try to fix table sorting
  • Fix One more default behaviour fix
  • Fix Phishing: Rework urls processing
  • Fix RBL: was missing some config schema
  • Fix Replies: Fix ‘Reply-To’ handling in task:get_reply_sender
  • Fix Rework metrics handling
  • Fix Save symcache on exit
  • Fix Selectors: Filter nil elements in lists
  • Fix Selectors: Properly fix implicit tostring for nils
  • Fix Try to fix some broken code in DMARC reporting plugin
  • Fix Urls: Fix processing of html urls when it comes to the flags
  • Fix Use proper buffer length
  • Fix Various visibility fixes
  • [Project] Add a simple css rule definition
  • [Project] Add css style skeleton
  • [Project] Add css syntax (adopted from ebnf)
  • [Project] Add css_selectors
  • [Project] Add doctest unit testing library
  • [Project] Add expected library
  • [Project] Add fmt library for simple string ops
  • [Project] Add fu2 library to better functions abstractions
  • [Project] Add hashing method
  • [Project] Add parsers skeleton
  • [Project] Add preliminary support of vcard parser
  • [Project] Add process exceptions for invisible text
  • [Project] Add some methods for css parser
  • [Project] Allow static libstdc++
  • [Project] Another whitespace hack
  • [Project] CSS: Various fixes in the declarations and values parsing
  • [Project] Cpp: Add robin-hood hash map library
  • [Project] Css: Add AST debug
  • [Project] Css: Add colors conversion functions
  • [Project] Css: Add dimensions handling
  • [Project] Css: Add display value support
  • [Project] Css: Add frozen library from https://github.com/serge-sans-paille/frozen/
  • [Project] Css: Add opacity support
  • [Project] Css: Add parser helpers to simplify debugging
  • [Project] Css: Add preliminary stylesheet support
  • [Project] Css: Add rules processing functions and tests
  • [Project] Css: Add simple selectors unit tests
  • [Project] Css: Add some c++ unit tests
  • [Project] Css: Add some debug methods
  • [Project] Css: Add some debug statements for the css parser
  • [Project] Css: Add some logical skeleton for declarations parser
  • [Project] Css: Add url/function tokens
  • [Project] Css: Allow at rules parsing
  • [Project] Css: Declarations parsing logic skeleton
  • [Project] Css: Enable conditional css parsing support from the HTML parser
  • [Project] Css: Finish generic lexer cases
  • [Project] Css: Fix HSL conversion
  • [Project] Css: Fix minus parsing
  • [Project] Css: Fix parser consumers nesting
  • [Project] Css: Fix parsing of the qualified rules
  • [Project] Css: Fix rules merging
  • [Project] Css: Further fixes to lexer
  • [Project] Css: Further steps to parse css colors + rework
  • [Project] Css: Further work on parser’s methods
  • [Project] Css: Implement backlog of css tokens
  • [Project] Css: Implement numbers and ident parsers
  • [Project] Css: Implement simple css selectors lookup
  • [Project] Css: Implement styles merging
  • [Project] Css: Make debug strings json like to simplify tests
  • [Project] Css: Minor adjustments
  • [Project] Css: More meat to the lexer
  • [Project] Css: Move some of the tests to the doctest
  • [Project] Css: Projected a parser
  • [Project] Css: Properties attachment logic
  • [Project] Css: Remove ragel from build targets (maybe keep for reference)
  • [Project] Css: Rework css block structure
  • [Project] Css: Rework flags of css properties
  • [Project] Css: Rework tokens structure
  • [Project] Css: Several fixes + tests
  • [Project] Css: Simplify checks
  • [Project] Css: Simplify debug code
  • [Project] Css: Start css selectors parsing logic
  • [Project] Css: Start semantic parsing for rules
  • [Project] Css: Start stylesheet implementation
  • [Project] Css: Tidy up lambdas
  • [Project] Css: rework tokeniser
  • [Project] Dmarc: Add dmarc report tool (WIP)
  • [Project] Dmarc: Add munging configuration
  • [Project] Dmarc: Add preliminary munging logic
  • [Project] Dmarc: Fix header removal
  • [Project] Dmarc: Fix munging logic
  • [Project] Dmarc: Use full recipient address instead of a domain map
  • [Project] Dmarc: Use zlists for dmarc reports
  • [Project] Dmarc_report: Add message generation logic
  • [Project] Dmarc_report: Add preliminary sending support
  • [Project] Fix lua bindings
  • [Project] Fix xml/sgml tags processing
  • [Project] Handle new modification
  • [Project] Html/CSS: Add transform from a CSS rule to html block
  • [Project] Html/CSS: Link html and css styles
  • [Project] Html/CSS: Switch styles parsing to css parser
  • [Project] Html/Css: Fix some issues found
  • [Project] Html/Css: Implement visibility rules for a block
  • [Project] Html: Add more tests cases and fix some more corner issues
  • [Project] Html: Add rows display type support
  • [Project] Html: Allow decode entities function to normalise spaces + unit tests
  • [Project] Html: Another rework of the tags structure
  • [Project] Html: Another try to fix unbalanced cases
  • [Project] Html: Fix crossing spans
  • [Project] Html: Fix parent propagation
  • [Project] Html: Further rework of the html parsing stuff
  • [Project] Html: Implement logic for tags pairing
  • [Project] Html: Implement rawtext state machine
  • [Project] Html: Insert closing tags as well :(
  • [Project] Html: More fixes
  • [Project] Html: More fixes
  • [Project] Html: More spaces logic fixes
  • [Project] Html: One more attempt to write text content
  • [Project] Html: Replace \0 in html content
  • [Project] Html: Rework img/a tags handling
  • [Project] Html: Rework propagation method
  • [Project] Html: Rework tags placement
  • [Project] Html: Rework transparency logic
  • [Project] Html: Support ‘hidden’ attribute
  • [Project] Html: Try another approach to append tags content
  • [Project] Html: Try to deal with bad unknown tags properly
  • [Project] Lua_aws: Add canonicalisation utility
  • [Project] Lua_aws: Add function to produce AWS Authorisation header
  • [Project] Lua_aws: Implement request signing
  • [Project] Lua_mime: Add lua_mime.modify_headers routine
  • [Project] Lua_task: Add modify_header method
  • [Project] Lua_task: Allow to extract modified headers
  • [Project] Make unescape code public for unit testing
  • [Project] More fixes for closed tags
  • [Project] More fixes to calculations
  • [Project] Rework API for the modified headers
  • [Project] Rework html visibility rule
  • [Project] Skeleton of the css library
  • [Project] Start headers modification API structure
  • [Project] Start working on AWS Lua API
  • [Project] Use lua_mime to modify headers
  • [Project] Use modified headers on dkim signing
  • [Project] Use string_view to constexpr variant unpacking
  • [Rework] Add composites manager concept
  • [Rework] Add tags definitions
  • [Rework] Allow C code to be compiled with C++ compiler
  • [Rework] Clickhouse: Store url flags
  • [Rework] Composites: Rewrite the composites logic
  • [Rework] Composites: Start rework of the composites framework
  • [Rework] Dmarc: Move check policy function to the common utils
  • [Rework] Dmarc: Rework reports keys structure
  • [Rework] Further work to make html content private
  • [Rework] Html/CSS: Remove css C bindings as they are useless now
  • [Rework] Html/CSS: Rework Lua bindings
  • [Rework] Html/Css: Start rework of the html blocks
  • [Rework] Html: Add images processing logic
  • [Rework] Html: Add traverse function
  • [Rework] Html: Another steps to get rid of gnode
  • [Rework] Html: Convert to variant
  • [Rework] Html: Deal with the utf_content part
  • [Rework] Html: Final rework part for the html processing code
  • [Rework] Html: Fix Lua bindings
  • [Rework] Html: Forgot to add the internal include
  • [Rework] Html: Further html urls rework
  • [Rework] Html: Further rework of the tags content extraction
  • [Rework] Html: Make parameters as a vector again
  • [Rework] Html: Move blocks part
  • [Rework] Html: Move images processing stuff
  • [Rework] Html: Rework lua bindings
  • [Rework] Html: Start html text extraction rework
  • [Rework] Html: Start refactoring of the html tags handling
  • [Rework] Html: Start removing of GNode stuff
  • [Rework] Html: Start rework of the html content structure
  • [Rework] Lua_magic: Try to detect text parts with 8bit characters for non-utf8 encodings
  • [Rework] Move HTML url functions and rework them
  • [Rework] Move and adopt entities handling logic
  • [Rework] Move common and rarely used dmarc code to the library
  • [Rework] Move compression routines outside of rspamd_util library
  • [Rework] Move entities/tags handling
  • [Rework] Phishing: Split from redirectors usage
  • [Rework] Redesign html blocks propagation logic
  • [Rework] Remove tag name string
  • [Rework] Rename phished url to a linked url
  • [Rework] Reorganize dmarc plugin and remove unsupported reporting code
  • [Rework] Reputation: Use more flexible types in get/set functions
  • [Rework] Require proper C++ environment for Rspamd build
  • [Rework] Rework extended urls output
  • [Rework] Rework tags parsing machine
  • [Rework] Slightly improve old regexp API
  • [Rework] Start conversion of the redis pool code to c++
  • [Rework] Try to resolve failed upstreams more agressively
  • [Rework] Use C++ utf8 library with unit tests to trim whitespaces
  • [Rework] Use C++ version for unicode normalisation
  • [Rework] Use C++ version of the lua threads pool
  • [Rules] Add raw addresses to MULTIPLE_FROM options
  • [Rules] Another fix to HTTP_TO_HTTPS rule
  • [Rules] Do not trigger HTML_SHORT_LINK_IMG on external images
  • [Rules] Extend FORGED_X_MAILER
  • [Rules] Extend OLD_X_MAILER
  • [Rules] Fix CTYPE_MIXED_BOGUS for text attachments
  • [Rules] Fix FPs for CTYPE_MIXED_BOGUS
  • [Rules] Fix HTTP_TO_HTTPS rule
  • [Rules] Fix HTTP_TO_HTTPS rule
  • [Rules] Fix zerofont rule (partially)
  • [Rules] Micro-optimize X_PHP_EVAL
  • [Rules] Reduce default weight for R_MISSING_CHARSET