Mastodon has no RBL/DNSBL support — nothing in it consults an outside
list when deciding whether to accept a signup, confirmed against v4.7.1
(the only outbound lookup in that path is EmailMxValidator's MX
resolution, which feeds the local email_domain_blocks table). So a
shared blocklist has to be imported rather than queried live, the same
way Garden Fence and other community lists propagate. These are the
pieces that make ours importable.
- ?format=txt on both per-list endpoints: one entry per line under a '#'
comment header, the form blocklists are traded in and the form a cron
job can consume without a JSON parser. The combined /api/blocks stays
JSON-only — a text rendering would mix CIDRs with domains in one file,
defeating the point. An unrecognised ?format is a 400 rather than a
silent fallback to JSON, and the enabled-gate still runs first so a
disabled deployment 404s either way.
- Access-Control-Allow-Origin: * on blocklist responses, so browser-side
admin tooling can read them. The data is already public.
- bin/yttrx-blocklist-import: standard-library-only importer another
admin can run against their own instance. Dry run unless --apply;
422 from Mastodon counts as "already blocked", not an error.
The importer defaults IP entries to sign_up_requires_approval rather
than the sign_up_block yttrx uses itself. The entries are whole ASN
routes, which suits yttrx because a flagged signup here is nearly always
datacenter/VPN/proxy space — that calibration isn't transferable, so an
importer gets the reviewable severity by default and has to opt into the
hard one.
Publishes the IP ranges and email domains the bot has auto-blocked as
JSON: GET /api/blocks, /api/blocks/ip-ranges, /api/blocks/email-domains,
each taking an optional ?limit=N.
The endpoints are unauthenticated, so BLOCKS_API_ENABLED gates them and
defaults to false — with it unset the paths 404 as if they didn't exist.
Publishing which ranges are already blocked also tells a spam signup
which ones to avoid, so opting in is a per-deployment call; yttrx.com
sets it true in the box's .env.
Responses assert only that a block exists: the blocked range/domain, a
signups count, and first/last seen. No account identifiers, and none of
the ipapi.is or check-mail.org classification that drove the decision —
republishing a paid reputation feed's verdicts on an open endpoint would
be redistributing their data rather than ours.
Supporting changes:
- signup_ip gains a block_cidr column (migrated in place on open) so the
API reports the network actually blocked rather than the signup IP.
Rows predating it fall back to that IP's /32 or /128, which is exactly
what was registered before range-blocking started 2026-07-15.
- register_ip_block / register_email_domain_block now return whether the
block landed, and the caller only marks it registered on success, so a
failed POST is no longer published as a block that exists.
datacenter/proxy/tor/abuser is a much cleaner bulk/bot-signup indicator
than vpn, which also flags plenty of privacy-conscious real users. A
strong-flagged signup now suspends immediately regardless of the email
signal; vpn-only still gets the normal held-welcome/ipblock/lowered-
threshold treatment, falling through to the existing combined-signal
suspend only if also paired with a flagged email domain.
register_ip_block always blocked the exact signup IP as a /32 (or /128
for v6), which is close to pointless for the datacenter/VPN/proxy space
these flags fire on: a repeat bad actor from the same provider almost
never reuses the exact same address, but very often reuses a different
one in the same block.
classify_signup_ip now returns a fourth value, block_cidr — ipapi.is's
asn.route CIDR when it's a valid network that actually contains the
signup IP (already being tracked in ipapi_range_cache purely for lookup
caching), falling back to the address's own /32 or /128 when no usable
route exists. register_ip_block blocks that instead of always deriving
a /32 itself.
Added range_cache_tests() covering the cache/fallback logic directly
(pure sqlite + ipaddress, no network), and updated the existing
ip_scrutiny_tests()/combined_signal_tests() mocks for the new 4-tuple
classify_signup_ip return and register_ip_block arity.
The hourly OR-based sweep (SUSPICIOUS_GRACE_HOURS) still handles a
single-signal flag as before. This adds an additional check in
process_signup(): a signup flagged by BOTH IP-scrutiny and
email-domain scrutiny at once is a stronger signal, so it's suspended
right away instead of waiting out the grace period, skipping the
hold/welcome path and the suspicious_watch entry entirely.
Gated behind new SUSPICIOUS_COMBINED_* env vars, dry-run first per the
usual rollout convention (unlike SUSPICIOUS_DRY_RUN, which shipped
live by design). Falls back to the normal held-welcome path if the
suspend API call fails, and respects ABUSE_ALLOWLIST.
Datacenter/hosting-IP-flagged signups are a strong enough spam signal on
their own that a full day of grace was mostly just delaying an inevitable
suspend. Cron cadence tightened from hourly to every 10 minutes so real
latency stays close to the new 1h window.
Watches every account flagged by IP-scrutiny or email-domain scrutiny at
signup and, once it goes live, records a baseline post/follow count. A
scheduled sweep (app/suspicious_sweep.py, run via cron on admin.yttrx.com)
suspends any watch past SUSPICIOUS_GRACE_HOURS with zero new posts and
zero new follows since that baseline; any activity clears the watch.
Works whether yttrx is open-registration or requires moderator approval,
since the watch starts at whichever event actually makes the account live
(account.created vs account.approved), same dual handling the welcome flow
already uses. Needs ABUSE_BOT_TOKEN re-minted with admin:read:accounts.
Classifies each signup's email domain (domain-only, GDPR-friendly) alongside
the existing IP scrutiny signal, with matching held-welcome and auto
email_domain_block behavior. A report against an account with a flagged
domain suspends immediately (no reporter-count threshold) and blocks the
domain, classified live from the report payload rather than any signup-time
record so it also covers pre-existing accounts. Ships CHECK_MAIL_DRY_RUN=true
by default, independent of ABUSE_DRY_RUN, so the new report-triggered suspend
path stays inert until watched.
pmb
waffle2k