"errors"
"fmt"
"io"
+ "math/bits"
"strconv"
+ "strings"
+ "unsafe"
"github.com/anacrolix/torrent/metainfo"
)
type ExtensionBit uint
+// https://www.bittorrent.org/beps/bep_0004.html
+// https://wiki.theory.org/BitTorrentSpecification.html#Reserved_Bytes
const (
- ExtensionBitDHT = 0 // http://www.bittorrent.org/beps/bep_0005.html
- ExtensionBitExtended = 20 // http://www.bittorrent.org/beps/bep_0010.html
- ExtensionBitFast = 2 // http://www.bittorrent.org/beps/bep_0006.html
+ ExtensionBitDht = 0 // http://www.bittorrent.org/beps/bep_0005.html
+ ExtensionBitFast = 2 // http://www.bittorrent.org/beps/bep_0006.html
+ ExtensionBitV2 = 7 // "Hybrid torrent legacy to v2 upgrade"
+ ExtensionBitAzureusExtensionNegotiation1 = 16
+ ExtensionBitAzureusExtensionNegotiation2 = 17
+ // LibTorrent Extension Protocol, http://www.bittorrent.org/beps/bep_0010.html
+ ExtensionBitLtep = 20
+ // https://wiki.theory.org/BitTorrent_Location-aware_Protocol_1
+ ExtensionBitLocationAwareProtocol = 43
+ ExtensionBitAzureusMessagingProtocol = 63 // https://www.bittorrent.org/beps/bep_0004.html
+
)
func handshakeWriter(w io.Writer, bb <-chan []byte, done chan<- error) {
PeerExtensionBits [8]byte
)
+var bitTags = []struct {
+ bit ExtensionBit
+ tag string
+}{
+ // Ordered by their bit position left to right.
+ {ExtensionBitAzureusMessagingProtocol, "amp"},
+ {ExtensionBitLocationAwareProtocol, "loc"},
+ {ExtensionBitLtep, "ltep"},
+ {ExtensionBitAzureusExtensionNegotiation2, "azen2"},
+ {ExtensionBitAzureusExtensionNegotiation1, "azen1"},
+ {ExtensionBitV2, "v2"},
+ {ExtensionBitFast, "fast"},
+ {ExtensionBitDht, "dht"},
+}
+
func (pex PeerExtensionBits) String() string {
- return hex.EncodeToString(pex[:])
+ pexHex := hex.EncodeToString(pex[:])
+ tags := make([]string, 0, len(bitTags)+1)
+ for _, bitTag := range bitTags {
+ if pex.GetBit(bitTag.bit) {
+ tags = append(tags, bitTag.tag)
+ pex.SetBit(bitTag.bit, false)
+ }
+ }
+ unknownCount := bits.OnesCount64(*(*uint64)((unsafe.Pointer(unsafe.SliceData(pex[:])))))
+ if unknownCount != 0 {
+ tags = append(tags, fmt.Sprintf("%v unknown", unknownCount))
+ }
+ return fmt.Sprintf("%v (%s)", pexHex, strings.Join(tags, ", "))
+
}
func NewPeerExtensionBytes(bits ...ExtensionBit) (ret PeerExtensionBits) {
}
func (pex PeerExtensionBits) SupportsExtended() bool {
- return pex.GetBit(ExtensionBitExtended)
+ return pex.GetBit(ExtensionBitLtep)
}
func (pex PeerExtensionBits) SupportsDHT() bool {
- return pex.GetBit(ExtensionBitDHT)
+ return pex.GetBit(ExtensionBitDht)
}
func (pex PeerExtensionBits) SupportsFast() bool {
return res, errors.New("unexpected protocol string")
}
- copyExact := func(dst []byte, src []byte) {
+ copyExact := func(dst, src []byte) {
if dstLen, srcLen := uint64(len(dst)), uint64(len(src)); dstLen != srcLen {
panic("dst len " + strconv.FormatUint(dstLen, 10) + " != src len " + strconv.FormatUint(srcLen, 10))
}