* Put parachain head hash into `CandidateDescriptor`

* Update guide

* Add some checks

* collation-generation: use persisted validation data

* node: remote FullValidationData API

* runtime: remove FullValidationData API

* backing tests: use persisted validation data

* FullCandidateReceipt: use persisted validation data

This is not a big change since this type is not used anywhere

* Remove ValidationData and TransientValidationData

Also update the guide

* fix bug where we over-eagerly remove backing spans for candidates we validate ourselves

* jaeger: watch importing of statements

* start approval types

* doc

* finish basic types

* add debug and codec impls to approval types

* grumbles

* remove unused AssignmentId

* remove aux-schema file

* guide: move erasure-root to candidate descriptor

* primitives: move erasure root to descriptor

* guide: unify candidate commitments and validation outputs

* primitives: unify validation outputs and candidate commitments

* parachains-runtime: fix fallout

* runtimes: fix fallout

* collation generation: fix fallout

* fix stray reference in primitives

* fix fallout in node-primitives

* fix remaining fallout in collation generation

* fix fallout in candidate validation

* fix fallout in runtime API subsystem

* fix fallout in subsystem messages

* fix fallout in candidate backing

* fix fallout in availability distribution

* don't clone

* clone

Co-authored-by: Sergei Shulepov <sergei@parity.io>

* Introduce CollatorFn type alias

* Make test-runtime imports consistent with rococo-runtime

* Update node/primitives/src/lib.rs

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* fix warnings

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* HRMP: Update the impl guide

* HRMP: Incorporate the channel notifications into the guide

* HRMP: Renaming in the impl guide

* HRMP: Constrain the maximum number of HRMP messages per candidate

This commit addresses the HRMP part of https://github.com/paritytech/polkadot/issues/1869

* XCM: Introduce HRMP related message types

* HRMP: Data structures and plumbing

* HRMP: Configuration

* HRMP: Data layout

* HRMP: Acceptance & Enactment

* HRMP: Test base logic

* Update adder collator

* HRMP: Runtime API for accessing inbound messages

Also, removing some redundant fully-qualified names.

* HRMP: Add diagnostic logging in acceptance criteria

* HRMP: Additional tests

* Self-review fixes

* save test refactorings for the next time

* Missed a return statement.

* a formatting blip

* Add missing logic for appending HRMP digests

* Remove the channel contents vectors which became empty

* Tighten HRMP channel digests invariants.

* Apply suggestions from code review

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* Remove a note about sorting for channel id

* Add missing rustdocs to the configuration

* Clarify and update the invariant for HrmpChannelDigests

* Make the onboarding invariant less sloppy

Namely, introduce `Paras::is_valid_para` (in fact, it already is present
in the implementation) and hook up the invariant to that.

Note that this says "within a session" because I don't want to make it
super strict on the session boundary. The logic on the session boundary
should be extremely careful.

* Make `CandidateCheckContext` use T::BlockNumber for hrmp_watermark

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* Make `CandidateHash` a real type

This pr adds a new type `CandidateHash` that is used instead of the
opaque `Hash` type. This helps to ensure on the type system level that
we are passing the correct types.

This pr also fixes wrong usage of `relay_parent` as `candidate_hash`
when communicating with the av storage.

* Update core-primitives/src/lib.rs

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* Wrap the lines

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* DMP: data structures and plumbing

* DMP: Implement DMP logic in the router module

DMP: Integrate DMP parts into the inclusion module

* DMP: Introduce the max size limit for the size of a downward message

* DMP: Runtime API for accessing inbound messages

* OCD

Small clean ups

* DMP: fix the naming of the error

* DMP: add caution about a non-existent recipient

* annoying whitespaces

* update guide

Add `CheckValidationOutputs` runtime api and also change the
candidate-validation stuff

* promote ValidationOutputs to global primitives

i.e. move it from node specific primitives to global v1 primitives. This
will be needed when we share it later in the runtime inclusion module

* refactor acceptance checks in the inclusion module

factor out the common code to share it during the block inclusion and
for the forthcoming CheckValidationOutputs runtime api.

Also note that the acceptance criteria was updated to incorporate checks
that exist now in candidate-validation

* plumb the runtime api outside

* extract validation_data from ValidationOutputs

* use runtime-api to check validation outputs

apart from that refactor, update docs and tidy a bit

* Update the maxium code size

This is to fix a test that performs an upgrade.

This pr changes the collation function to also pass the current relay
parent the parachain block should be build on.

This pr changes the collator interface function to return an optional
collation instead of a collation. This is required as the parachain
itself can fail to generate a valid collation for various reason. Now if
the collation fails it will return `None`.

Besides that the pr adds some `RuntimeDebug` derive for `ValidationData`
and removes some whitespaces.

* update primitives

* correct parent_head field

* make hrmp field pub

* refactor validation data: runtime

* refactor validation data: messages

* add arguments to full_validation_data runtime API

* port runtime API

* mostly port over candidate validation

* remove some parameters from ValidationParams

* guide: update candidate validation

* update candidate outputs

* update ValidationOutputs in primitives

* port over candidate validation

* add a new test for no-transient behavior

* update util runtime API wrappers

* candidate backing

* fix missing imports

* change some fields of validation data around

* runtime API impl

* update candidate validation

* fix backing tests

* grumbles from review

* fix av-store tests

* fix some more crates

* fix provisioner tests

* fix availability distribution tests

* port collation-generation to new validation data

* fix overseer tests

* Update roadmap/implementers-guide/src/node/utility/candidate-validation.md

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* start sketching out a collation generation subsystem

* invent a basic strategy for double initialization

* clean up warnings

* impl util requests from runtime assuming a context instead of a FromJob sender

* implement collation generation algorithm from guide

* update AllMessages in tests

* fix trivial review comments

* remove another redundant declaration from merge

* filter availability cores by para_id

* handle new activations each in their own async task

* update guide according to the actual current implementation

* add initialization to guide

* add general-purpose subsystem_test_harness helper

* write first handle_new_activations test

* add test that handle_new_activations filters local_validation_data requests

* add (failing) test of collation distribution message sending

* rustfmt

* broken: work on fixing sender test

Unfortunately, for reasons that are not yet clear, despite the public key
and checked data being identical, the signer is not producing an identical
signature. This commit produces this output (among more):

signing with  Public(c4733ab0bbe3ba4c096685d1737a7f498cdbdd167a767d04a21dc7df12b8c858 (5GWHUNm5...))
checking with Public(c4733ab0bbe3ba4c096685d1737a7f498cdbdd167a767d04a21dc7df12b8c858 (5GWHUNm5...))
signed payload:  [4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 10, 0, 0, 0, c7, e5, c0, 64, 7a, db, fe, 44, 81, e5, 51, 11, 79, 9f, a5, 63, 93, 94, 3c, c4, 36, c6, 30, 36, c2, c5, 44, a2, 1b, db, b7, 82, 3, 17, a, 2e, 75, 97, b7, b7, e3, d8, 4c, 5, 39, 1d, 13, 9a, 62, b1, 57, e7, 87, 86, d8, c0, 82, f2, 9d, cf, 4c, 11, 13, 14]
checked payload: [4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 10, 0, 0, 0, c7, e5, c0, 64, 7a, db, fe, 44, 81, e5, 51, 11, 79, 9f, a5, 63, 93, 94, 3c, c4, 36, c6, 30, 36, c2, c5, 44, a2, 1b, db, b7, 82, 3, 17, a, 2e, 75, 97, b7, b7, e3, d8, 4c, 5, 39, 1d, 13, 9a, 62, b1, 57, e7, 87, 86, d8, c0, 82, f2, 9d, cf, 4c, 11, 13, 14]

* fix broken test

* collation function returns commitments hash

It doesn't look like we use the actual commitments data anywhere, and
it's not obvious if there are any fields of `CandidateCommitments`
not available to the collator, so this commit just assigns them the
entire responsibility of generating the hash.

* add missing overseer impls

* calculating erasure coding is polkadot's responsibility, not cumulus

* concurrentize per-relay_parent requests

* update networking types

* port over overseer-protocol message types

* Add the collation protocol to network bridge

* message sending

* stub for ConnectToValidators

* add some helper traits and methods to protocol types

* add collator protocol message

* leaves-updating

* peer connection and disconnection

* add utilities for dispatching multiple events

* implement message handling

* add an observedrole enum with equality and no sentry nodes

* derive partial-eq on network bridge event

* add PartialEq impls for network message types

* add Into implementation for observedrole

* port over existing network bridge tests

* add some more tests

* port bitfield distribution

* port over bitfield distribution tests

* add codec indices

* port PoV distribution

* port over PoV distribution tests

* port over statement distribution

* port over statement distribution tests

* update overseer and service-new

* address review comments

* port availability distribution

* port over availability distribution tests

* sketch out provisioner basics

* handle provisionable data

* stub out select_inherent_data

* split runtime APIs into sub-chapters to improve linkability

* explain SignedAvailabilityBitfield semantics

* add internal link to further documentation

* some more work figuring out how the provisioner can do its thing

* fix broken link

* don't import enum variants where it's one layer deep

* make request_availability_cores a free fn in util

* document more precisely what should happen on block production

* finish first-draft implementation of provisioner

* start working on the full and proper backed candidate selection rule

* Pass number of block under construction via RequestInherentData

* Revert "Pass number of block under construction via RequestInherentData"

This reverts commit 850fe62cc0dfb04252580c21a985962000e693c8.

That initially looked like the better approach--it spent the time
budget for fetching the block number in the proposer, instead of
the provisioner, and that felt more appropriate--but it turns out
not to be obvious how to get the block number of the block under
construction from within the proposer. The Chain API may be less
ideal, but it should be easier to implement.

* wip: get the block under production from the Chain API

* add ChainApiMessage to AllMessages

* don't break the run loop if a provisionable data channel closes

* clone only those backed candidates which are coherent

* propagate chain_api subsystem through various locations

* add delegated_subsystem! macro to ease delegating subsystems

Unfortunately, it doesn't work right:

```
error[E0446]: private type `CandidateBackingJob` in public interface
   --> node/core/backing/src/lib.rs:775:1
    |
86  | struct CandidateBackingJob {
    | - `CandidateBackingJob` declared as private
...
775 | delegated_subsystem!(CandidateBackingJob as CandidateBackingSubsystem);
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can't leak private type
```

I'm not sure precisely what's going wrong, here; I suspect the problem is
the use of `$job as JobTrait>::RunArgs` and `::ToJob`; the failure would be
that it's not reifying the types to verify that the actual types are public,
but instead referring to them via `CandidateBackingJob`, which is in fact private;
that privacy is the point.

Going to see if I can generic my way out of this, but we may be headed for a
quick revert here.

* fix delegated_subsystem

The invocation is a bit more verbose than I'd prefer, but it's also
more explicit about what types need to be public. I'll take it as a win.

* add provisioning subsystem; reduce public interface of provisioner

* deny missing docs in provisioner

* refactor core selection per code review suggestion

This is twice as much code when measured by line, but IMO it is
in fact somewhat clearer to read, so overall a win.

Also adds an improved rule for selecting availability bitfields,
which (unlike the previous implementation) guarantees that the
appropriate postconditions hold there.

* fix bad merge double-declaration

* update guide with (hopefully) complete provisioner candidate selection procedure

* clarify candidate selection algorithm

* Revert "clarify candidate selection algorithm"

This reverts commit c68a02ac9cf42b3a4a28eb197d38633a40d0e3e6.

* clarify candidate selection algorithm

* update provisioner to implement candidate selection per the guide

* add test that no more than one bitfield is selected per validator

* add test that each selected bitfield corresponds to an occupied core

* add test that more set bits win conflicts

* add macro for specializing runtime requests; specailize all runtime requests

* add tests harness for select_candidates tests

* add first real select_candidates test, fix test_harness

* add mock overseer and test that success is possible

* add test that the candidate selection algorithm picks the right ones

* make candidate selection test somewhat more stringent

* Sort out validation errors

* Typo

* Fixed wasm/android build

* Fixed bad merge

* rename GlobalValidationSchedule to GlobalValidationData

* guide: update candidate descriptor to contain validation data hash

* guide: add note in inclusion module about checking validation data hash

* primitives: update CandidateDescriptor to contain new hash

* fix payload computation

* add helpers for computing validation data to runtime modules

* guide: note routines

* inclusion: check validation data hash and fix local_validation_data bug

* add a case to candidate_checks and improve that test substantially

* bump versions

* address review comments

* add a test for including code upgrade

* bump kusama version

* bump westend & polkadot versions

* Use SpawnNamed instead of Spawn in Overseer

* reexport SpawnNamed and fix doc tests

* Fix deps

* create a v1 primitives module

* Improve guide on availability types

* punctuate

* new parachains runtime uses new primitives

* tests of new runtime now use new primitives

* add ErasureChunk to guide

* export erasure chunk from v1 primitives

* subsystem crate uses v1 primitives

* node-primitives uses new v1 primitives

* port overseer to new primitives

* new-proposer uses v1 primitives (no ParachainHost anymore)

* fix no-std compilation for primitives

* service-new uses v1 primitives

* network-bridge uses new primitives

* statement distribution uses v1 primitives

* PoV distribution uses v1 primitives; add PoV::hash fn

* move parachain to v0

* remove inclusion_inherent module and place into v1

* remove everything from primitives crate root

* remove some unused old types from v0 primitives

* point everything else at primitives::v0

* squanch some warns up

* add RuntimeDebug import to no-std as well

* port over statement-table and validation

* fix final errors in validation and node-primitives

* add dummy Ord impl to committed candidate receipt

* guide: update CandidateValidationMessage

* add primitive for validationoutputs

* expand CandidateValidationMessage further

* bikeshed

* add some impls to omitted-validation-data and available-data

* expand CandidateValidationMessage

* make erasure-coding generic over v1/v0

* update usages of erasure-coding

* implement commitments.hash()

* use Arc<Pov> for CandidateValidation

* improve new erasure-coding method names

* fix up candidate backing

* update docs a bit

* fix most tests and add short-circuiting to make_pov_available

* fix remainder of candidate backing tests

* squanching warns

* squanch it up

* some fallout

* overseer fallout

* free from polkadot-test-service hell

* Updates guide for CandidateBacking

* Move assignment types to primitives

* Initial implementation.

* More functionality

* use assert_matches

* Changes to report misbehaviors

* Some fixes after a review

* Remove a blank line

* Update guide and some types

* Adds run_job function

* Some comments and refactorings

* Fix review

* Remove warnings

* Use summary in kicking off validation

* Parallelize requests

* Validation provides local and global validation params

* Test issued validity tracking

* Nits from review

* set up data types and control flow for statement distribution

* add some set-like methods to View

* implement sending to peers

* start fixing equivocation handling

* Add a section to the statement distribution subsystem on equivocations and flood protection

* fix typo and amend wording

* implement flood protection

* have peer knowledge tracker follow when peer first learns about a candidate

* send dependents after circulating

* add another TODO

* trigger send in one more place

* refactors from review

* send new statements to candidate backing

* instantiate active head data with runtime API values

* track our view changes and peer view changes

* apply a benefit to peers who send us statements we want

* remove unneeded TODO

* add some comments and improve Hash implementation

* start tests and fix `note_statement`

* test active_head seconding logic

* test that the per-peer tracking logic works

* test per-peer knowledge tracker

* test that peer view updates lead to messages being sent

* test statement circulation

* address review comments

* have view set methods return references

* network bridge skeleton

* move some primitives around and add debug impls

* protocol registration glue & abstract network interface

* add send_msgs to subsystemctx

* select logic

* transform different events into actions and handle

* implement remaining network bridge state machine

* start test skeleton

* make network methods asynchronous

* extract subsystem out to subsystem crate

* port over overseer to subsystem context trait

* fix minimal example

* fix overseer doc test

* update network-bridge crate

* write a subsystem test-helpers crate

* write a network test helper for network-bridge

* set up (broken) view test

* Revamp network to be more async-friendly and not require Sync

* fix spacing

* fix test compilation

* insert side-channel for actions

* Add some more message types to AllMessages

* introduce a test harness

* add some tests

* ensure service compiles and passes tests

* fix typo

* fix...

* add signed wrapper, typedef SignedStatement

* typedef SignedAvailabilityBitfield

* implement Signed wrapper

This is strictly an addition as of this commit; nothing is yet
changed in existing behavior.

* inline getters, remove review comment

* move EncodeAs, Signed from node::primitives to primitives::parachain

* Refactor SignedAvailabilityBitfield to use Signed

* don't double-encode real payload

This isn't an ideal solution, because it depends on the
implementation details of how SCALE encodes tuples, but OTOH
that behavior seems unlikely to change anytime soon.

* fix build errors

* cause the runtime to build properly with the new changes

Not sure why cargo check didn't catch this earlier; oh well.

* fix runtime tests and separate SignedStatement from SignedFullStatement

* better explain why CompactStatement exists

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

* introduce polkadot-node-primitives

* guide: change statement distribution message types

* guide: remove variant from `CandidateSelectionMessage`

* add a few more message types

* add TODOs

* Almost all messages

* NewBackedCandidate notification

* Formatting

* Use AttestedCandidate as BackedCandidate

* Update node/primitives/src/lib.rs

Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>

* Fix the tests

* Bring in types from #1242

* Adds network bridge messages

* More message types from doc

* use fn pointer type

* Fixes from the review

* Add missing Runtime subsystem message

* rename to CandidateValidationMessage and fix tests

Co-authored-by: Fedor Sakharov <fedor.sakharov@gmail.com>
Co-authored-by: Peter Goodspeed-Niklaus <coriolinus@users.noreply.github.com>