Add drafty prototype

1 files changed, 0 insertions, 286 deletions

diff --git a/pkg/monitor/monitor.go b/pkg/monitor/monitor.go
deleted file mode 100644
index 5f7a629..0000000
--- a/pkg/monitor/monitor.go
+++ /dev/null
@@ -1,286 +0,0 @@
-// Package monitor provides a Certificate Transparency monitor that tails a list
-// of logs which can be updated dynamically while running.  All emitted progress
-// messages have been verified by the monitor to be included in the log's
-// append-only Merkle tree with regard to the initial start-up state.  It is up
-// to the user to process the monitor's progress, errors, and persist state.
-//
-// Implement the Matcher interface to customize which certificates should be
-// included in a log's progress messages, or use any of the existing matchers
-// provided by this package (see for example MatchAll and MatchWildcards).
-package monitor
-
-import (
-	"context"
-	"crypto/sha256"
-	"fmt"
-	"net/http"
-	"sync"
-	"time"
-
-	ct "github.com/google/certificate-transparency-go"
-	"github.com/google/certificate-transparency-go/client"
-	"github.com/google/certificate-transparency-go/jsonclient"
-	"github.com/google/certificate-transparency-go/scanner"
-	"rgdd.se/silent-ct/internal/merkle"
-)
-
-const (
-	UserAgentPrefix   = "rgdd.se/silent-ct"
-	DefaultContact    = "unknown-user"
-	DefaultChunkSize  = 256 // TODO: increase me
-	DefaultBatchSize  = 128 // TODO: increase me
-	DefaultNumWorkers = 2
-)
-
-type Config struct {
-	Contact    string // Something that help log operators get in touch
-	ChunkSize  int    // Min number of leaves to propagate a chunk without matches
-	BatchSize  int    // Max number of certificates to accept per worker
-	NumWorkers int    // Number of parallel workers to use for each log
-
-	// Callback determines which certificates are interesting to detect
-	Callback Matcher
-}
-
-type Monitor struct {
-	Config
-}
-
-func New(cfg Config) (Monitor, error) {
-	if cfg.Contact == "" {
-		cfg.Contact = "unknown-user"
-	}
-	if cfg.ChunkSize <= 0 {
-		cfg.ChunkSize = DefaultChunkSize
-	}
-	if cfg.BatchSize <= 0 {
-		cfg.BatchSize = DefaultBatchSize
-	}
-	if cfg.NumWorkers <= 0 {
-		cfg.NumWorkers = DefaultNumWorkers
-	}
-	if cfg.Callback == nil {
-		cfg.Callback = &MatchAll{}
-	}
-	return Monitor{Config: cfg}, nil
-}
-
-func (mon *Monitor) Run(ctx context.Context, metadataCh chan []MessageLogConfig, eventCh chan MessageLogProgress, errorCh chan error) {
-	var wg sync.WaitGroup
-	var sctx context.Context
-	var cancel context.CancelFunc
-
-	for {
-		select {
-		case <-ctx.Done():
-			return
-		case metadata := <-metadataCh:
-			fmt.Printf("DEBUG: received new list with %d logs\n", len(metadata))
-			if cancel != nil {
-				fmt.Printf("DEBUG: stopping all log tailers\n")
-				cancel()
-				wg.Wait()
-			}
-
-			sctx, cancel = context.WithCancel(ctx)
-			for _, md := range metadata {
-				fmt.Printf("DEBUG: starting log tailer %s\n", md.Metadata.URL)
-				wg.Add(1)
-				go func(lcfg MessageLogConfig) {
-					defer wg.Done()
-
-					opts := jsonclient.Options{Logger: &noout{}, UserAgent: UserAgentPrefix + ":" + mon.Contact}
-					cli, err := client.New(string(lcfg.Metadata.URL), &http.Client{}, opts)
-					if err != nil {
-						errorCh <- fmt.Errorf("unable to configure %s: %v", lcfg.Metadata.URL, err)
-						return
-					}
-
-					chunkCh := make(chan *chunk)
-					defer close(chunkCh)
-
-					t := tail{mon.Config, *cli, chunkCh, eventCh, errorCh}
-					if err := t.run(sctx, lcfg.State); err != nil {
-						errorCh <- fmt.Errorf("unable to continue tailing %s: %v", lcfg.Metadata.URL, err)
-					}
-				}(md)
-			}
-		}
-	}
-}
-
-type tail struct {
-	mcfg Config
-	cli  client.LogClient
-
-	chunkCh chan *chunk
-	eventCh chan MessageLogProgress
-	errorCh chan error
-}
-
-func (t *tail) run(ctx context.Context, state MonitorState) error {
-	var wg sync.WaitGroup
-	defer wg.Wait()
-
-	mctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		defer cancel()
-		t.sequence(mctx, state)
-	}()
-
-	fetcher := scanner.NewFetcher(&t.cli, &scanner.FetcherOptions{
-		BatchSize:     t.mcfg.BatchSize,
-		StartIndex:    int64(state.NextIndex),
-		ParallelFetch: t.mcfg.NumWorkers,
-		Continuous:    true,
-	})
-	callback := func(eb scanner.EntryBatch) {
-		c := chunk{startIndex: uint64(eb.Start)}
-		for i := 0; i < len(eb.Entries); i++ {
-			c.leafHashes = append(c.leafHashes, merkle.HashLeafNode(eb.Entries[i].LeafInput))
-			match, err := t.mcfg.Callback.Match(eb.Entries[i].LeafInput, eb.Entries[i].ExtraData)
-			if err != nil {
-				c.errors = append(c.errors, fmt.Errorf("while processing index %d for %s: %v", i, t.cli.BaseURI(), err))
-			} else if match {
-				c.matches = append(c.matches, LogEntry{
-					LeafIndex: uint64(i),
-					LeafData:  eb.Entries[i].LeafInput,
-					ExtraData: eb.Entries[i].ExtraData,
-				})
-			}
-		}
-		t.chunkCh <- &c
-	}
-	return fetcher.Run(mctx, callback)
-}
-
-func (t *tail) sequence(ctx context.Context, state MonitorState) {
-	heap := newChunks()
-	for {
-		select {
-		case <-ctx.Done():
-			return
-		case c := <-t.chunkCh:
-			heap.push(c)
-			if heap.gap(state.NextIndex) {
-				continue
-			}
-			c = heap.pop()
-			if len(c.matches) == 0 && len(c.leafHashes) < t.mcfg.ChunkSize {
-				heap.push(c)
-				continue // TODO: don't trigger if we havn't run nextState for too long
-			}
-			nextState, err := t.nextState(ctx, state, c)
-			if err != nil {
-				t.errorCh <- err
-				heap.push(c)
-				continue
-			}
-
-			state = nextState
-			t.eventCh <- MessageLogProgress{State: state, Matches: c.matches, Errors: c.errors}
-		}
-	}
-}
-
-func (t *tail) nextState(ctx context.Context, state MonitorState, c *chunk) (MonitorState, error) {
-	newState, err := t.nextConsistentState(ctx, state)
-	if err != nil {
-		return MonitorState{}, err
-	}
-	newState, err = t.nextIncludedState(ctx, state, c)
-	if err != nil {
-		return MonitorState{}, err
-	}
-	return newState, nil
-}
-
-func (t *tail) nextConsistentState(ctx context.Context, state MonitorState) (MonitorState, error) {
-	sth, err := getSignedTreeHead(ctx, &t.cli)
-	if err != nil {
-		return MonitorState{}, ErrorFetch{URL: t.cli.BaseURI(), Msg: "get-sth", Err: err}
-	}
-	oldSize := state.TreeSize
-	oldRoot := state.SHA256RootHash
-	newSize := sth.TreeSize
-	newRoot := sth.SHA256RootHash
-
-	proof, err := getConsistencyProof(ctx, &t.cli, oldSize, newSize)
-	if err != nil {
-		return MonitorState{}, ErrorFetch{URL: t.cli.BaseURI(), Msg: "get-consistency", STH: sth, Err: err}
-	}
-	if err := merkle.VerifyConsistency(oldSize, newSize, oldRoot, newRoot, unslice(proof)); err != nil {
-		return MonitorState{}, ErrorMerkleTree{URL: t.cli.BaseURI(), Msg: "consistency", STH: sth, Err: err}
-	}
-
-	fmt.Printf("DEBUG: consistently updated STH from size %d to %d\n", oldSize, newSize)
-	return MonitorState{LogState: LogState{*sth}, NextIndex: state.NextIndex}, nil
-}
-
-func (t *tail) nextIncludedState(ctx context.Context, state MonitorState, c *chunk) (MonitorState, error) {
-	leafHash := c.leafHashes[0]
-	oldSize := state.NextIndex + uint64(len(c.leafHashes))
-	iproof, err := getInclusionProof(ctx, &t.cli, leafHash, oldSize)
-	if err != nil {
-		err = fmt.Errorf("leaf hash %x and tree size %d: %v", leafHash[:], oldSize, err)
-		return MonitorState{}, ErrorFetch{URL: t.cli.BaseURI(), Msg: "get-inclusion", Err: err}
-	}
-	if got, want := uint64(iproof.LeafIndex), state.NextIndex; got != want {
-		err := fmt.Errorf("leaf hash %x and tree size %d: expected leaf index %d but got %d", leafHash[:], oldSize, got, want)
-		return MonitorState{}, ErrorMerkleTree{URL: t.cli.BaseURI(), Msg: "proof-index", Err: err}
-	}
-	oldRoot, err := merkle.TreeHeadFromRangeProof(c.leafHashes, state.NextIndex, unslice(iproof.AuditPath))
-	if err != nil {
-		return MonitorState{}, ErrorMerkleTree{URL: t.cli.BaseURI(), Msg: "inclusion", Err: err}
-	}
-
-	newSize := state.TreeSize
-	newRoot := state.SHA256RootHash
-	cproof, err := getConsistencyProof(ctx, &t.cli, oldSize, newSize)
-	if err != nil {
-		err = fmt.Errorf("from size %d to %d: %v", oldSize, newSize, err)
-		return MonitorState{}, ErrorFetch{URL: t.cli.BaseURI(), Msg: "get-consistency", Err: err}
-	}
-	if err := merkle.VerifyConsistency(oldSize, newSize, oldRoot, newRoot, unslice(cproof)); err != nil {
-		err = fmt.Errorf("from size %d to %d: %v", oldSize, newSize, err)
-		return MonitorState{}, ErrorMerkleTree{URL: t.cli.BaseURI(), Msg: "consistency", Err: err}
-	}
-
-	state.NextIndex += uint64(len(c.leafHashes))
-	return state, nil
-}
-
-func getInclusionProof(ctx context.Context, cli *client.LogClient, leafHash [sha256.Size]byte, size uint64) (*ct.GetProofByHashResponse, error) {
-	rctx, cancel := context.WithTimeout(ctx, 10*time.Second)
-	defer cancel()
-	return cli.GetProofByHash(rctx, leafHash[:], size)
-}
-
-func getConsistencyProof(ctx context.Context, cli *client.LogClient, oldSize, newSize uint64) ([][]byte, error) {
-	if oldSize == 0 || oldSize >= newSize {
-		return [][]byte{}, nil
-	}
-	rctx, cancel := context.WithTimeout(ctx, 10*time.Second)
-	defer cancel()
-	return cli.GetSTHConsistency(rctx, oldSize, newSize)
-}
-
-func getSignedTreeHead(ctx context.Context, cli *client.LogClient) (*ct.SignedTreeHead, error) {
-	rctx, cancel := context.WithTimeout(ctx, 10*time.Second)
-	defer cancel()
-	return cli.GetSTH(rctx)
-}
-
-func unslice(hashes [][]byte) [][sha256.Size]byte {
-	var ret [][sha256.Size]byte
-	for _, hash := range hashes {
-		var h [sha256.Size]byte
-		copy(h[:], hash)
-		ret = append(ret, h)
-	}
-	return ret
-}