Mario Fetka
41 lines
1.7 KiB
Markdown
41 lines
1.7 KiB
Markdown
# Spam and malware scanning
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Bongo uses two independent scanners. `bongoantispam` sends mail to a standard
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SpamAssassin `spamd` service for content classification. `bongoavirus` uses
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ClamAV for malware detection. Neither service replaces the other.
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The antispam agent is fail-open: a connection failure, malformed response or
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configured size limit leaves the original message available for normal
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delivery and records the problem in the log. It never sends a rejection or
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bounce to the apparent sender. A successful SpamAssassin `PROCESS` response
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replaces the queued copy with the processed message containing the normal
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`X-Spam-*` headers and marks the envelope as already checked.
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The default `antispam` JSON configuration is:
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```json
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{
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"version": 1,
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"enabled": true,
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"timeout": 15,
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"maximum_message_size": 52428800,
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"maximum_response_size": 53477376,
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"hosts": ["127.0.0.1"]
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}
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```
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`hosts` accepts the existing `host:port:weight` syntax and can list several
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`spamd` servers. Port 783 is used when no port is specified. The response limit
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must be at least as large as the input limit because SpamAssassin adds headers.
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Spam folder rules should match SpamAssassin's `X-Spam-Status` header. A high
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score quarantine is deliberately not implemented through the historical
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global quarantine queue: quarantine state belongs to the recipient and must be
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visible and releasable through that user's task list. Until that per-user path
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is active, mail is tagged and can be filed by Sieve without being destroyed.
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The systemd unit only orders Bongo after common ClamAV and SpamAssassin unit
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names when those services are present. It does not pull either scanner in, so
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remote scanners and installations without one of the optional services remain
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supported.
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