feat: refine invocation (#202)

internal/refine/refine.go

@@ -0,0 +1,121 @@
+package refine
+
+import (
+	"errors"
+
+	"github.com/eigerco/strawberry/internal/block"
+	"github.com/eigerco/strawberry/internal/crypto"
+	"github.com/eigerco/strawberry/internal/polkavm"
+	"github.com/eigerco/strawberry/internal/polkavm/host_call"
+	"github.com/eigerco/strawberry/internal/polkavm/interpreter"
+	"github.com/eigerco/strawberry/internal/state"
+	"github.com/eigerco/strawberry/internal/work"
+	"github.com/eigerco/strawberry/pkg/serialization/codec/jam"
+)
+
+const (
+	RefineCost = 10
+)
+
+var (
+	ErrBad = errors.New("service’s code was not available for lookup") // BAD
+	ErrBig = errors.New("code beyond the maximum size allowed")        // BIG
+)
+
+type Refine struct {
+	state state.State
+}
+
+// InvokePVM ΨR(H, NG, NS , H, Y, X, H, Y, ⟦G⟧, ⟦Y⟧, N) → (Y ∪ J, ⟦Y⟧)
+func (r *Refine) InvokePVM(
+	serviceCodePredictionHash crypto.Hash, gas uint64, serviceIndex block.ServiceId,
+	workPackageHash crypto.Hash, workPayload []byte, refinementContext block.RefinementContext,
+	authorizerHash crypto.Hash, authorizerHashOutput []byte, importedSegments []polkavm.Segment,
+	extrinsicDataBlobs [][]byte, exportOffset uint64,
+) ([]byte, []polkavm.Segment, error) {
+	// let a = E(s, y, p, c, a, ↕o, ↕[↕x | x <− x])
+	args, err := jam.Marshal(struct {
+		ServiceIndex         block.ServiceId
+		WorkPayload          []byte
+		WorkPackageHash      crypto.Hash
+		RefinementContext    block.RefinementContext
+		AuthorizerHash       crypto.Hash
+		AuthorizerHashOutput []byte
+		ExtrinsicDataBlobs   [][]byte
+	}{
+		ServiceIndex:         serviceIndex,
+		WorkPayload:          workPayload,
+		WorkPackageHash:      workPackageHash,
+		RefinementContext:    refinementContext,
+		AuthorizerHash:       authorizerHash,
+		AuthorizerHashOutput: authorizerHashOutput,
+		ExtrinsicDataBlobs:   extrinsicDataBlobs, // we assume the extrinsic data is a ordered sequence
+	})
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// if s ∉ K(δ) ∨ Λ(δ[s], ct, c) = ∅ then (BAD, [])
+	service, ok := r.state.Services[serviceIndex]
+	if !ok {
+		return nil, nil, ErrBad
+	}
+	code := service.LookupPreimage(refinementContext.LookupAnchor.Timeslot, serviceCodePredictionHash)
+	if code == nil {
+		return nil, nil, ErrBad
+	}
+
+	// if |Λ(δ[s], ct, c)| > W_C then (BIG, [])
+	if len(code) > work.MaxSizeServiceCode {
+		return nil, nil, ErrBig
+	}
+
+	// F ∈ Ω⟨(D⟨N → M⟩, ⟦Y⟧)⟩∶ (n, ϱ, ω, μ, (m, e))
+	hostCall := func(hostCall uint32, gasCounter polkavm.Gas, regs polkavm.Registers, mem polkavm.Memory, ctxPair polkavm.RefineContextPair) (polkavm.Gas, polkavm.Registers, polkavm.Memory, polkavm.RefineContextPair, error) {
+		switch hostCall {
+		case host_call.HistoricalLookupID:
+			gasCounter, regs, mem, ctxPair, err = host_call.HistoricalLookup(gasCounter, regs, mem, ctxPair, serviceIndex, r.state.Services, refinementContext.LookupAnchor.Timeslot)
+		case host_call.ImportID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Import(gasCounter, regs, mem, ctxPair, importedSegments)
+		case host_call.ExportID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Export(gasCounter, regs, mem, ctxPair, exportOffset)
+		case host_call.GasID:
+			gasCounter, regs, err = host_call.GasRemaining(gasCounter, regs)
+		case host_call.MachineID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Machine(gasCounter, regs, mem, ctxPair)
+		case host_call.PeekID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Peek(gasCounter, regs, mem, ctxPair)
+		case host_call.ZeroID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Zero(gasCounter, regs, mem, ctxPair)
+		case host_call.PokeID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Poke(gasCounter, regs, mem, ctxPair)
+		case host_call.VoidID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Void(gasCounter, regs, mem, ctxPair)
+		case host_call.InvokeID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Invoke(gasCounter, regs, mem, ctxPair)
+		case host_call.ExpungeID:
+			gasCounter, regs, mem, ctxPair, err = host_call.Expunge(gasCounter, regs, mem, ctxPair)
+		default:
+			regs[polkavm.A0] = uint64(host_call.WHAT)
+			gasCounter -= RefineCost
+
+		}
+		return gasCounter, regs, mem, ctxPair, nil
+	}
+
+	// (g, r, (m, e)) = ΨM(Λ(δ[s], ct, c), 0, g, a, F, (∅, []))∶
+	_, result, ctxPair, err := interpreter.InvokeWholeProgram(code, 0, gas, args, hostCall, polkavm.RefineContextPair{
+		IntegratedPVMMap: make(map[uint64]polkavm.IntegratedPVM),
+		Segments:         []polkavm.Segment{},
+	})
+
+	// if r ∈ {∞, ☇} then (r, [])
+	if err != nil {
+		panicErr := &polkavm.ErrPanic{}
+		if errors.Is(err, polkavm.ErrOutOfGas) || errors.As(err, &panicErr) {
+			return nil, nil, err
+		}
+	}
+
+	return result, ctxPair.Segments, err
+}

internal/work/constants.go

@@ -1,6 +1,7 @@
 package work
 
 const (
+	MaxSizeServiceCode                  = 4000000                                                                // WC = 4000000: The maximum size of service code in octets.
 	MaxNumberOfEntries                  = 1 << 11                                                                // WM = 2^11: The maximum number of entries in a work-package manifest.
 	NumberOfErasureCodecPiecesInSegment = 6                                                                      // WP = 6: The number of erasure-coded pieces in a segment.
 	SizeOfErasureCodecPiecesInOctets    = 684                                                                    // WE = 684: The basic size of erasure-coded pieces in octets.