diff options
Diffstat (limited to 'vendor/github.com/pion/transport/vnet/chunk.go')
| -rw-r--r-- | vendor/github.com/pion/transport/vnet/chunk.go | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/vendor/github.com/pion/transport/vnet/chunk.go b/vendor/github.com/pion/transport/vnet/chunk.go new file mode 100644 index 0000000..7a87a2f --- /dev/null +++ b/vendor/github.com/pion/transport/vnet/chunk.go @@ -0,0 +1,283 @@ +package vnet + +import ( + "fmt" + "net" + "strconv" + "strings" + "sync/atomic" + "time" +) + +type tcpFlag uint8 + +const ( + tcpFIN tcpFlag = 0x01 + tcpSYN tcpFlag = 0x02 + tcpRST tcpFlag = 0x04 + tcpPSH tcpFlag = 0x08 + tcpACK tcpFlag = 0x10 +) + +func (f tcpFlag) String() string { + var sa []string + if f&tcpFIN != 0 { + sa = append(sa, "FIN") + } + if f&tcpSYN != 0 { + sa = append(sa, "SYN") + } + if f&tcpRST != 0 { + sa = append(sa, "RST") + } + if f&tcpPSH != 0 { + sa = append(sa, "PSH") + } + if f&tcpACK != 0 { + sa = append(sa, "ACK") + } + + return strings.Join(sa, "-") +} + +// Generate a base36-encoded unique tag +// See: https://play.golang.org/p/0ZaAID1q-HN +var assignChunkTag = func() func() string { //nolint:gochecknoglobals + var tagCtr uint64 + + return func() string { + n := atomic.AddUint64(&tagCtr, 1) + return strconv.FormatUint(n, 36) + } +}() + +// Chunk represents a packet passed around in the vnet +type Chunk interface { + setTimestamp() time.Time // used by router + getTimestamp() time.Time // used by router + getSourceIP() net.IP // used by router + getDestinationIP() net.IP // used by router + setSourceAddr(address string) error // used by nat + setDestinationAddr(address string) error // used by nat + + SourceAddr() net.Addr + DestinationAddr() net.Addr + UserData() []byte + Tag() string + Clone() Chunk + Network() string // returns "udp" or "tcp" + String() string +} + +type chunkIP struct { + timestamp time.Time + sourceIP net.IP + destinationIP net.IP + tag string +} + +func (c *chunkIP) setTimestamp() time.Time { + c.timestamp = time.Now() + return c.timestamp +} + +func (c *chunkIP) getTimestamp() time.Time { + return c.timestamp +} + +func (c *chunkIP) getDestinationIP() net.IP { + return c.destinationIP +} + +func (c *chunkIP) getSourceIP() net.IP { + return c.sourceIP +} + +func (c *chunkIP) Tag() string { + return c.tag +} + +type chunkUDP struct { + chunkIP + sourcePort int + destinationPort int + userData []byte +} + +func newChunkUDP(srcAddr, dstAddr *net.UDPAddr) *chunkUDP { + return &chunkUDP{ + chunkIP: chunkIP{ + sourceIP: srcAddr.IP, + destinationIP: dstAddr.IP, + tag: assignChunkTag(), + }, + sourcePort: srcAddr.Port, + destinationPort: dstAddr.Port, + } +} + +func (c *chunkUDP) SourceAddr() net.Addr { + return &net.UDPAddr{ + IP: c.sourceIP, + Port: c.sourcePort, + } +} + +func (c *chunkUDP) DestinationAddr() net.Addr { + return &net.UDPAddr{ + IP: c.destinationIP, + Port: c.destinationPort, + } +} + +func (c *chunkUDP) UserData() []byte { + return c.userData +} + +func (c *chunkUDP) Clone() Chunk { + var userData []byte + if c.userData != nil { + userData = make([]byte, len(c.userData)) + copy(userData, c.userData) + } + + return &chunkUDP{ + chunkIP: chunkIP{ + timestamp: c.timestamp, + sourceIP: c.sourceIP, + destinationIP: c.destinationIP, + tag: c.tag, + }, + sourcePort: c.sourcePort, + destinationPort: c.destinationPort, + userData: userData, + } +} + +func (c *chunkUDP) Network() string { + return udpString +} + +func (c *chunkUDP) String() string { + src := c.SourceAddr() + dst := c.DestinationAddr() + return fmt.Sprintf("%s chunk %s %s => %s", + src.Network(), + c.tag, + src.String(), + dst.String(), + ) +} + +func (c *chunkUDP) setSourceAddr(address string) error { + addr, err := net.ResolveUDPAddr(udpString, address) + if err != nil { + return err + } + c.sourceIP = addr.IP + c.sourcePort = addr.Port + return nil +} + +func (c *chunkUDP) setDestinationAddr(address string) error { + addr, err := net.ResolveUDPAddr(udpString, address) + if err != nil { + return err + } + c.destinationIP = addr.IP + c.destinationPort = addr.Port + return nil +} + +type chunkTCP struct { + chunkIP + sourcePort int + destinationPort int + flags tcpFlag // control bits + userData []byte // only with PSH flag + // seq uint32 // always starts with 0 + // ack uint32 // always starts with 0 +} + +func newChunkTCP(srcAddr, dstAddr *net.TCPAddr, flags tcpFlag) *chunkTCP { + return &chunkTCP{ + chunkIP: chunkIP{ + sourceIP: srcAddr.IP, + destinationIP: dstAddr.IP, + tag: assignChunkTag(), + }, + sourcePort: srcAddr.Port, + destinationPort: dstAddr.Port, + flags: flags, + } +} + +func (c *chunkTCP) SourceAddr() net.Addr { + return &net.TCPAddr{ + IP: c.sourceIP, + Port: c.sourcePort, + } +} + +func (c *chunkTCP) DestinationAddr() net.Addr { + return &net.TCPAddr{ + IP: c.destinationIP, + Port: c.destinationPort, + } +} + +func (c *chunkTCP) UserData() []byte { + return c.userData +} + +func (c *chunkTCP) Clone() Chunk { + userData := make([]byte, len(c.userData)) + copy(userData, c.userData) + + return &chunkTCP{ + chunkIP: chunkIP{ + timestamp: c.timestamp, + sourceIP: c.sourceIP, + destinationIP: c.destinationIP, + }, + sourcePort: c.sourcePort, + destinationPort: c.destinationPort, + userData: userData, + } +} + +func (c *chunkTCP) Network() string { + return "tcp" +} + +func (c *chunkTCP) String() string { + src := c.SourceAddr() + dst := c.DestinationAddr() + return fmt.Sprintf("%s %s chunk %s %s => %s", + src.Network(), + c.flags.String(), + c.tag, + src.String(), + dst.String(), + ) +} + +func (c *chunkTCP) setSourceAddr(address string) error { + addr, err := net.ResolveTCPAddr("tcp", address) + if err != nil { + return err + } + c.sourceIP = addr.IP + c.sourcePort = addr.Port + return nil +} + +func (c *chunkTCP) setDestinationAddr(address string) error { + addr, err := net.ResolveTCPAddr("tcp", address) + if err != nil { + return err + } + c.destinationIP = addr.IP + c.destinationPort = addr.Port + return nil +} |