本文整理汇总了Golang中github.com/tsg/gopacket/layers.TCP.LayerPayload方法的典型用法代码示例。如果您正苦于以下问题:Golang TCP.LayerPayload方法的具体用法?Golang TCP.LayerPayload怎么用?Golang TCP.LayerPayload使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类github.com/tsg/gopacket/layers.TCP
的用法示例。
在下文中一共展示了TCP.LayerPayload方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Golang代码示例。
示例1: AssembleWithTimestamp
// AssembleWithTimestamp reassembles the given TCP packet into its appropriate
// stream.
//
// The timestamp passed in must be the timestamp the packet was seen.
// For packets read off the wire, time.Now() should be fine. For packets read
// from PCAP files, CaptureInfo.Timestamp should be passed in. This timestamp
// will affect which streams are flushed by a call to FlushOlderThan.
//
// Each Assemble call results in, in order:
//
// zero or one calls to StreamFactory.New, creating a stream
// zero or one calls to Reassembled on a single stream
// zero or one calls to ReassemblyComplete on the same stream
func (a *Assembler) AssembleWithTimestamp(netFlow gopacket.Flow, t *layers.TCP, timestamp time.Time) {
// Ignore empty TCP packets
if !t.SYN && !t.FIN && !t.RST && len(t.LayerPayload()) == 0 {
if *debugLog {
log.Println("ignoring useless packet")
}
return
}
a.ret = a.ret[:0]
key := key{netFlow, t.TransportFlow()}
var conn *connection
// This for loop handles a race condition where a connection will close, lock
// the connection pool, and remove itself, but before it locked the connection
// pool it's returned to another Assemble statement. This should loop 0-1
// times for the VAST majority of cases.
for {
conn = a.connPool.getConnection(
key, !t.SYN && len(t.LayerPayload()) == 0, timestamp)
if conn == nil {
if *debugLog {
log.Printf("%v got empty packet on otherwise empty connection", key)
}
return
}
conn.mu.Lock()
if !conn.closed {
break
}
conn.mu.Unlock()
}
if conn.lastSeen.Before(timestamp) {
conn.lastSeen = timestamp
}
seq, bytes := Sequence(t.Seq), t.Payload
if conn.nextSeq == invalidSequence {
if t.SYN {
if *debugLog {
log.Printf("%v saw first SYN packet, returning immediately, seq=%v", key, seq)
}
a.ret = append(a.ret, Reassembly{
Bytes: bytes,
Skip: 0,
Start: true,
Seen: timestamp,
})
conn.nextSeq = seq.Add(len(bytes) + 1)
} else {
if *debugLog {
log.Printf("%v waiting for start, storing into connection", key)
}
a.insertIntoConn(t, conn, timestamp)
}
} else if diff := conn.nextSeq.Difference(seq); diff > 0 {
if *debugLog {
log.Printf("%v gap in sequence numbers (%v, %v) diff %v, storing into connection", key, conn.nextSeq, seq, diff)
}
a.insertIntoConn(t, conn, timestamp)
} else {
bytes, conn.nextSeq = byteSpan(conn.nextSeq, seq, bytes)
if *debugLog {
log.Printf("%v found contiguous data (%v, %v), returning immediately", key, seq, conn.nextSeq)
}
a.ret = append(a.ret, Reassembly{
Bytes: bytes,
Skip: 0,
End: t.RST || t.FIN,
Seen: timestamp,
})
}
if len(a.ret) > 0 {
a.sendToConnection(conn)
}
conn.mu.Unlock()
}