diff options
Diffstat (limited to 'les')
| -rw-r--r-- | les/handler.go | 4 | ||||
| -rw-r--r-- | les/protocol.go | 8 |
2 files changed, 11 insertions, 1 deletions
diff --git a/les/handler.go b/les/handler.go index d9d07f014..ea2ec3324 100644 --- a/les/handler.go +++ b/les/handler.go @@ -442,7 +442,9 @@ func (pm *ProtocolManager) handleMsg(p *peer) error { if err := msg.Decode(&req); err != nil { return errResp(ErrDecode, "%v: %v", msg, err) } - + if err := req.sanityCheck(); err != nil { + return err + } update, size := req.Update.decode() if p.rejectUpdate(size) { return errResp(ErrRequestRejected, "") diff --git a/les/protocol.go b/les/protocol.go index ebf581473..5fdf32b74 100644 --- a/les/protocol.go +++ b/les/protocol.go @@ -149,6 +149,14 @@ type announceData struct { Update keyValueList } +// sanityCheck verifies that the values are reasonable, as a DoS protection +func (a *announceData) sanityCheck() error { + if tdlen := a.Td.BitLen(); tdlen > 100 { + return fmt.Errorf("too large block TD: bitlen %d", tdlen) + } + return nil +} + // sign adds a signature to the block announcement by the given privKey func (a *announceData) sign(privKey *ecdsa.PrivateKey) { rlp, _ := rlp.EncodeToBytes(announceBlock{a.Hash, a.Number, a.Td}) |