-
Notifications
You must be signed in to change notification settings - Fork 174
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
* add default validator support * add an implementation for basic seqno as nonce validation * missing return * the nonce belongs to the origin peer * add note about rust predicament * add seqno validator tests * minor test tweak, ensure at least 1ms before replay
- Loading branch information
Showing
4 changed files
with
456 additions
and
22 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,101 @@ | ||
| package pubsub | ||
|
|
||
| import ( | ||
| "context" | ||
| "encoding/binary" | ||
| "sync" | ||
|
|
||
| "github.com/libp2p/go-libp2p/core/peer" | ||
| ) | ||
|
|
||
| // PeerMetadataStore is an interface for storing and retrieving per peer metadata | ||
| type PeerMetadataStore interface { | ||
| // Get retrieves the metadata associated with a peer; | ||
| // It should return nil if there is no metadata associated with the peer and not an error. | ||
| Get(context.Context, peer.ID) ([]byte, error) | ||
| // Put sets the metadata associated with a peer. | ||
| Put(context.Context, peer.ID, []byte) error | ||
| } | ||
|
|
||
| // BasicSeqnoValidator is a basic validator, usable as a default validator, that ignores replayed | ||
| // messages outside the seen cache window. The validator uses the message seqno as a peer-specific | ||
| // nonce to decide whether the message should be propagated, comparing to the maximal nonce store | ||
| // in the peer metadata store. This is useful to ensure that there can be no infinitely propagating | ||
| // messages in the network regardless of the seen cache span and network diameter. | ||
| // It requires that pubsub is instantiated with a strict message signing policy and that seqnos | ||
| // are not disabled, ie it doesn't support anonymous mode. | ||
| // | ||
| // Warning: See https://github.com/libp2p/rust-libp2p/issues/3453 | ||
| // TL;DR: rust is currently violating the spec by issuing a random seqno, which creates an | ||
| // interoperability hazard. We expect this issue to be addressed in the not so distant future, | ||
| // but keep this in mind if you are in a mixed environment with (older) rust nodes. | ||
| type BasicSeqnoValidator struct { | ||
| mx sync.RWMutex | ||
| meta PeerMetadataStore | ||
| } | ||
|
|
||
| // NewBasicSeqnoValidator constructs a BasicSeqnoValidator using the givven PeerMetadataStore. | ||
| func NewBasicSeqnoValidator(meta PeerMetadataStore) ValidatorEx { | ||
| val := &BasicSeqnoValidator{ | ||
| meta: meta, | ||
| } | ||
| return val.validate | ||
| } | ||
|
|
||
| func (v *BasicSeqnoValidator) validate(ctx context.Context, _ peer.ID, m *Message) ValidationResult { | ||
| p := m.GetFrom() | ||
|
|
||
| v.mx.RLock() | ||
| nonceBytes, err := v.meta.Get(ctx, p) | ||
| v.mx.RUnlock() | ||
|
|
||
| if err != nil { | ||
| log.Warn("error retrieving peer nonce: %s", err) | ||
| return ValidationIgnore | ||
| } | ||
|
|
||
| var nonce uint64 | ||
| if len(nonceBytes) > 0 { | ||
| nonce = binary.BigEndian.Uint64(nonceBytes) | ||
| } | ||
|
|
||
| var seqno uint64 | ||
| seqnoBytes := m.GetSeqno() | ||
| if len(seqnoBytes) > 0 { | ||
| seqno = binary.BigEndian.Uint64(seqnoBytes) | ||
| } | ||
|
|
||
| // compare against the largest seen nonce | ||
| if seqno <= nonce { | ||
| return ValidationIgnore | ||
| } | ||
|
|
||
| // get the nonce and compare again with an exclusive lock before commiting (cf concurrent validation) | ||
| v.mx.Lock() | ||
| defer v.mx.Unlock() | ||
|
|
||
| nonceBytes, err = v.meta.Get(ctx, p) | ||
| if err != nil { | ||
| log.Warn("error retrieving peer nonce: %s", err) | ||
| return ValidationIgnore | ||
| } | ||
|
|
||
| if len(nonceBytes) > 0 { | ||
| nonce = binary.BigEndian.Uint64(nonceBytes) | ||
| } | ||
|
|
||
| if seqno <= nonce { | ||
| return ValidationIgnore | ||
| } | ||
|
|
||
| // update the nonce | ||
| nonceBytes = make([]byte, 8) | ||
| binary.BigEndian.PutUint64(nonceBytes, seqno) | ||
|
|
||
| err = v.meta.Put(ctx, p, nonceBytes) | ||
| if err != nil { | ||
| log.Warn("error storing peer nonce: %s", err) | ||
| } | ||
|
|
||
| return ValidationAccept | ||
| } |
Oops, something went wrong.