rfc: client certificates for servers using SMP protocol as clients (opertors' chat relays, notification servers, service bots) (#1534)

* rfc: client certificates for high volume clients (opertors' chat relays, notification servers, service bots)

* client certificates types (WIP)

* parameterize Transport

* protocol/schema/api changes

* agent API

* rename command

* agent subscriptions return local ClientServiceId to chat

* verify transmissions

* fix receiving client certificates, refactor

* ntf server: remove shared queue for all notification subscriptions (#1543)

* ntf server: remove shared queue for all notification subscriptions

* wait for subscriber with timeout

* safer

* refactor

* log

* remove unused

* WIP service subscriptions and associations, refactor

* process service subscriptions

* rename

* simplify switching subscriptions

* SMP service handshake with additional server handshake response

* notification delivery and STM persistence for services

* smp server: database storage, store log, fix encoding for STORE error, replace String with Text in locks and error

* stats

* more stats

* rename SMP commands

* service subscriptions in ntf server agent (tests fail)

* fix

* refactor

* exports

* subscribe ntf server as service for associated queues

* test ntf service connection, fix SOKS response, fix service associations not removed in STM storage

* INI option to support services

* ntf server: downgrade subscriptions when service is no longer supported, track counts of subscribed queues

* smp protocol: include service certificate fingerprint in the string signed over with entity key (TODO two tests fail)

* fix test

* ntf server prometheus stats, use Int64 in SOKS/ENDS responses (to avoid conversions), additional error status for ntf subscription

* update RFC

* refactor useServiceAuth to avoid ad hoc decisions about which commands use service signatures, and to prohibit service signatures on other commands

* remove duplicate service signature syntax check from checkCredentials, it is checked in verifyTransmission

* service errors, todos

* fix checkCredentials in ntf server, service errors

* refactor service auth

* refactor

* service agent: store returned queue count instead of expected

* refactor serverThread

* refactor serviceSig

* rename

* refactor, rename, test repeat NSUB service association

* respond with error to SUBS

* smp server: export/import service records between database and store log

* comment

* comments

* ghc 8.10.7

src/Simplex/Messaging/Server/QueueStore/Postgres/Migrations.hs

@@ -13,7 +13,8 @@ serverSchemaMigrations :: [(String, Text, Maybe Text)]
 serverSchemaMigrations =
   [ ("20250207_initial", m20250207_initial, Nothing),
     ("20250319_updated_index", m20250319_updated_index, Just down_m20250319_updated_index),
-    ("20250320_short_links", m20250320_short_links, Just down_m20250320_short_links)
+    ("20250320_short_links", m20250320_short_links, Just down_m20250320_short_links),
+    ("20250514_service_certs", m20250514_service_certs, Just down_m20250514_service_certs)
   ]
 
 -- | The list of migrations in ascending order by date
@@ -48,7 +49,7 @@ CREATE INDEX idx_msg_queues_deleted_at ON msg_queues (deleted_at);
     |]
 
 m20250319_updated_index :: Text
-m20250319_updated_index = 
+m20250319_updated_index =
   T.pack
     [r|
 DROP INDEX idx_msg_queues_deleted_at;
@@ -119,3 +120,42 @@ UPDATE msg_queues SET recipient_keys = substring(recipient_keys from 3);
 
 ALTER TABLE msg_queues RENAME COLUMN recipient_keys TO recipient_key;
     |]
+
+m20250514_service_certs :: Text
+m20250514_service_certs =
+  T.pack
+    [r|
+CREATE TABLE services(
+  service_id BYTEA NOT NULL,
+  service_role TEXT NOT NULL,
+  service_cert BYTEA NOT NULL,
+  service_cert_hash BYTEA NOT NULL UNIQUE,
+  created_at BIGINT NOT NULL,
+  PRIMARY KEY (service_id)
+);
+
+CREATE INDEX idx_services_service_role ON services(service_role);
+
+ALTER TABLE msg_queues
+  ADD COLUMN rcv_service_id BYTEA REFERENCES services(service_id) ON DELETE SET NULL ON UPDATE RESTRICT,
+  ADD COLUMN ntf_service_id BYTEA REFERENCES services(service_id) ON DELETE SET NULL ON UPDATE RESTRICT;
+
+CREATE INDEX idx_msg_queues_rcv_service_id ON msg_queues(rcv_service_id, deleted_at);
+CREATE INDEX idx_msg_queues_ntf_service_id ON msg_queues(ntf_service_id, deleted_at);
+    |]
+
+down_m20250514_service_certs :: Text
+down_m20250514_service_certs =
+  T.pack
+    [r|
+DROP INDEX idx_msg_queues_rcv_service_id;
+DROP INDEX idx_msg_queues_ntf_service_id;
+
+ALTER TABLE msg_queues
+  DROP COLUMN rcv_service_id,
+  DROP COLUMN ntf_service_id;
+
+DROP INDEX idx_services_service_role;
+
+DROP TABLE services;
+    |]