Discovery Neo Oclib

This commit is contained in:
mr
2026-05-27 16:17:00 +02:00
parent 7f951afd41
commit 6ce6e6fe7d
20 changed files with 1436 additions and 1133 deletions
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package stream
// DTN_cache.go — Disconnection Network Tolerance cache for outbound stream requests.
//
// When a stream write fails because the remote peer is unreachable, the request
// is saved here and retried on the next tick. Two levels are defined:
//
// - DTNCritical : retry indefinitely (create / update / delete resource).
// - DTNModerate : up to DTNMaxModerateRetries retries, then abandon.
//
// Pubsub messages and search streams are explicitly excluded.
// Streams initiated from the indexer side are never enqueued here.
//
// # Crash-resilient persistence
//
// Critical entries are written to an encrypted file (AES-256-GCM) so they
// survive a node crash/restart. The AES key is derived deterministically from
// the node's Ed25519 private key via HKDF-SHA256 — no extra secret to manage.
// Moderate entries are intentionally not persisted: their retry budget is small
// enough that re-loading them after a restart would be misleading.
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"crypto/sha256"
"encoding/json"
"io"
"os"
"path/filepath"
"sync"
"time"
oclib "cloud.o-forge.io/core/oc-lib"
"cloud.o-forge.io/core/oc-lib/tools"
"golang.org/x/crypto/hkdf"
"oc-discovery/conf"
pp "github.com/libp2p/go-libp2p/core/peer"
"github.com/libp2p/go-libp2p/core/protocol"
)
type DTNLevel int
const (
DTNCritical DTNLevel = iota // retry until the message is delivered
DTNModerate // retry up to DTNMaxModerateRetries times
)
const DTNMaxModerateRetries = 3
const DTNRetryInterval = 15 * time.Second
// DTNProtocols maps each stream protocol to its DTN level.
// Protocols absent from this map receive no caching (e.g. ProtocolSearchResource).
var DTNProtocols = map[protocol.ID]DTNLevel{
// Critical — data mutations that must eventually be delivered.
ProtocolCreateResource: DTNCritical,
ProtocolUpdateResource: DTNCritical,
ProtocolDeleteResource: DTNCritical,
// Moderate — confirmations / config / planner: 3 retries before abandon.
ProtocolVerifyResource: DTNModerate,
ProtocolSendPlanner: DTNModerate,
ProtocolConsidersResource: DTNModerate,
ProtocolMinioConfigResource: DTNModerate,
ProtocolAdmiraltyConfigResource: DTNModerate,
ProtocolSourcePresignResource: DTNModerate,
}
// DTNEntryJSON is the on-disk representation of a DTNEntry.
// pp.AddrInfo and protocol.ID don't have built-in JSON tags so we flatten them.
type DTNEntryJSON struct {
DID string `json:"did"`
ResourceID string `json:"resource_id,omitempty"`
ForceCritical bool `json:"force_critical,omitempty"`
Addr pp.AddrInfo `json:"addr"`
DT *tools.DataType `json:"dt,omitempty"`
User string `json:"user"`
Payload []byte `json:"payload"`
Proto protocol.ID `json:"proto"`
Retries int `json:"retries"`
AddedAt time.Time `json:"added_at"`
}
type DTNEntry struct {
did string
resourceID string // UUID of the resource; empty for non-resource payloads (planner, config)
forceCritical bool // true when destination is NANO: all protocols become critical
addr pp.AddrInfo
dt *tools.DataType
user string
payload []byte
proto protocol.ID
retries int
addedAt time.Time
}
// isEffectivelyCritical returns true when the entry must be retried indefinitely,
// either because its protocol is inherently critical or because the destination
// is a NANO peer (forceCritical).
func (e *DTNEntry) isEffectivelyCritical() bool {
return DTNProtocols[e.proto] == DTNCritical || e.forceCritical
}
func (e *DTNEntry) toJSON() DTNEntryJSON {
return DTNEntryJSON{
DID: e.did,
ResourceID: e.resourceID,
ForceCritical: e.forceCritical,
Addr: e.addr,
DT: e.dt,
User: e.user,
Payload: e.payload,
Proto: e.proto,
Retries: e.retries,
AddedAt: e.addedAt,
}
}
func entryFromJSON(j DTNEntryJSON) *DTNEntry {
return &DTNEntry{
did: j.DID,
resourceID: j.ResourceID,
forceCritical: j.ForceCritical,
addr: j.Addr,
dt: j.DT,
user: j.User,
payload: j.Payload,
proto: j.Proto,
retries: j.Retries,
addedAt: j.AddedAt,
}
}
type DTNCache struct {
mu sync.Mutex
entries []*DTNEntry
// aesKey is the derived AES-256 key used for on-disk encryption.
// Nil when key derivation failed: persistence is disabled but the in-memory
// cache continues to function normally.
aesKey []byte
}
// newDNTCache initialises the cache, derives the encryption key, and restores
// any critical entries that were persisted before the last crash.
func newDNTCache() *DTNCache {
log := oclib.GetLogger()
c := &DTNCache{}
key, err := deriveDNTKey()
if err != nil {
log.Warn().Err(err).Msg("[dnt] key derivation failed — persistence disabled")
} else {
c.aesKey = key
c.loadFromDisk()
}
return c
}
// extractResourceID returns the "id" field from a JSON resource payload.
// Returns "" when the payload is not a resource object (planner, config, etc.).
func extractResourceID(payload []byte) string {
var obj struct {
ID string `json:"id"`
}
if err := json.Unmarshal(payload, &obj); err != nil {
return ""
}
return obj.ID
}
// enqueue adds an entry to the cache, respecting the resource lifecycle.
// Deduplication key is (did, resourceID): same resource to the same peer keeps
// only the latest mutation. resourceID is empty for non-resource payloads
// (planner, config), in which case deduplication falls back to did alone.
//
// - DELETE is terminal: any subsequent mutation on the same key is discarded.
// - UPDATE cannot be followed by CREATE: the resource already exists remotely.
// - All other cases replace the existing entry (newer mutation supersedes).
func (c *DTNCache) enqueue(e *DTNEntry) {
c.mu.Lock()
found, mutated := false, false
for i, existing := range c.entries {
if existing.did != e.did || existing.resourceID != e.resourceID {
continue
}
found = true
if existing.proto == ProtocolDeleteResource ||
(existing.proto == ProtocolUpdateResource && e.proto == ProtocolCreateResource) {
break // discard new entry silently — existing state is authoritative
}
c.entries[i] = e
mutated = true
break
}
if !found {
c.entries = append(c.entries, e)
mutated = true
}
c.mu.Unlock()
if mutated && e.isEffectivelyCritical() {
go c.persistToDisk()
}
}
// peersWithPending returns the distinct peer IDs (did) that have at least one
// critical entry in the cache. Used to populate Heartbeat.PendingContact.
func (c *DTNCache) peersWithPending() []string {
c.mu.Lock()
defer c.mu.Unlock()
seen := map[string]struct{}{}
var out []string
for _, e := range c.entries {
if e.isEffectivelyCritical() {
if _, ok := seen[e.did]; !ok {
seen[e.did] = struct{}{}
out = append(out, e.did)
}
}
}
return out
}
// drain atomically removes and returns all current entries.
func (c *DTNCache) drain() []*DTNEntry {
c.mu.Lock()
defer c.mu.Unlock()
out := c.entries
c.entries = nil
return out
}
// requeue puts entries back at the head of the list, preserving any new
// entries added while the retry loop was running.
func (c *DTNCache) requeue(entries []*DTNEntry) {
if len(entries) == 0 {
return
}
c.mu.Lock()
defer c.mu.Unlock()
c.entries = append(entries, c.entries...)
}
// ── Persistence ──────────────────────────────────────────────────────────────
// DTNCachePath returns the path of the on-disk cache file, placed next to the
// node's private key so it lives on the same persistent volume.
func DTNCachePath() string {
return filepath.Join(filepath.Dir(conf.GetConfig().PrivateKeyPath), "dnt_cache.bin")
}
// deriveDNTKey derives a 32-byte AES key from the node's Ed25519 private key
// using HKDF-SHA256. The derivation is deterministic: the same key is always
// produced from the same private key, so no symmetric secret needs storing.
func deriveDNTKey() ([]byte, error) {
priv, err := tools.LoadKeyFromFilePrivate()
if err != nil {
return nil, err
}
// Raw() on a libp2p Ed25519 private key returns the 64-byte representation
// (32-byte seed || 32-byte public key). We use the full 64 bytes as IKM.
raw, err := priv.Raw()
if err != nil {
return nil, err
}
reader := hkdf.New(sha256.New, raw, nil, []byte("oc-discovery/dnt-cache/v1"))
key := make([]byte, 32)
if _, err := io.ReadFull(reader, key); err != nil {
return nil, err
}
return key, nil
}
// persistToDisk encrypts all current critical entries and writes them to disk.
// Non-critical entries are deliberately excluded — they are not worth restoring
// after a restart given their limited retry budget.
func (c *DTNCache) persistToDisk() {
if c.aesKey == nil {
return
}
log := oclib.GetLogger()
c.mu.Lock()
var toSave []DTNEntryJSON
for _, e := range c.entries {
if e.isEffectivelyCritical() {
toSave = append(toSave, e.toJSON())
}
}
c.mu.Unlock()
plaintext, err := json.Marshal(toSave)
if err != nil {
return
}
block, err := aes.NewCipher(c.aesKey)
if err != nil {
return
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return
}
nonce := make([]byte, gcm.NonceSize())
if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
return
}
ciphertext := gcm.Seal(nonce, nonce, plaintext, nil)
path := DTNCachePath()
tmp := path + ".tmp"
if err := os.WriteFile(tmp, ciphertext, 0600); err != nil {
log.Warn().Err(err).Msg("[dnt] failed to write cache file")
return
}
if err := os.Rename(tmp, path); err != nil {
log.Warn().Err(err).Msg("[dnt] failed to rename cache file")
_ = os.Remove(tmp)
}
}
// loadFromDisk decrypts the on-disk cache and re-enqueues only critical entries.
// Errors (missing file, decryption failure) are non-fatal: the cache simply
// starts empty, which is safe.
func (c *DTNCache) loadFromDisk() {
if c.aesKey == nil {
return
}
log := oclib.GetLogger()
path := DTNCachePath()
data, err := os.ReadFile(path)
if err != nil {
if !os.IsNotExist(err) {
log.Warn().Err(err).Msg("[dnt] failed to read cache file")
}
return
}
block, err := aes.NewCipher(c.aesKey)
if err != nil {
return
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return
}
if len(data) < gcm.NonceSize() {
log.Warn().Msg("[dnt] cache file too short, ignoring")
return
}
nonce, ciphertext := data[:gcm.NonceSize()], data[gcm.NonceSize():]
plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
if err != nil {
log.Warn().Err(err).Msg("[dnt] cache file decryption failed (key mismatch?), ignoring")
return
}
var saved []DTNEntryJSON
if err := json.Unmarshal(plaintext, &saved); err != nil {
log.Warn().Err(err).Msg("[dnt] cache file unmarshal failed, ignoring")
return
}
count := 0
for _, j := range saved {
// Only restore critical entries — moderate entries are intentionally
// not persisted, but this guard defends against format changes.
e := entryFromJSON(j)
if !e.isEffectivelyCritical() {
continue
}
c.entries = append(c.entries, e)
count++
}
if count > 0 {
log.Info().Int("count", count).Msg("[dnt] restored critical entries from disk")
}
}
// ── Retry loop ────────────────────────────────────────────────────────────────
// startDNTLoop runs the background retry goroutine. Call once after init.
func (s *StreamService) startDNTLoop() {
logger := oclib.GetLogger()
ticker := time.NewTicker(DTNRetryInterval)
defer ticker.Stop()
// retryEntries attempts delivery for the given entries and returns those
// that must be kept for the next round.
retryEntries := func(entries []*DTNEntry) []*DTNEntry {
var keep []*DTNEntry
for _, e := range entries {
_, err := s.write(e.did, &e.addr, e.dt, e.user, e.payload, e.proto)
if err == nil {
if e.isEffectivelyCritical() {
logger.Info().Str("proto", string(e.proto)).Str("peer", e.did).
Msg("[dnt] critical message delivered after retry")
} else {
logger.Info().Str("proto", string(e.proto)).Str("peer", e.did).
Int("retries", e.retries).Msg("[dnt] moderate message delivered after retry")
}
continue
}
if e.isEffectivelyCritical() {
keep = append(keep, e)
} else {
e.retries++
if e.retries < DTNMaxModerateRetries {
keep = append(keep, e)
} else {
logger.Warn().Str("proto", string(e.proto)).Str("peer", e.did).
Int("retries", e.retries).Msg("[dnt] moderate message abandoned after max retries")
}
}
}
return keep
}
for {
select {
case <-ticker.C:
entries := s.dnt.drain()
if len(entries) == 0 {
continue
}
s.dnt.requeue(retryEntries(entries))
go s.dnt.persistToDisk()
case peerID := <-s.dntNudge:
// A peer just signalled it is reachable — retry its entries immediately.
entries := s.dnt.drain()
var forPeer, other []*DTNEntry
for _, e := range entries {
if e.did == peerID {
forPeer = append(forPeer, e)
} else {
other = append(other, e)
}
}
kept := retryEntries(forPeer)
s.dnt.requeue(append(kept, other...))
if len(kept) < len(forPeer) {
go s.dnt.persistToDisk()
}
}
}
}