63 lines
1.7 KiB
Go
63 lines
1.7 KiB
Go
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package mux
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// MatchFunc allows custom logic for mapping packets to an Endpoint
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type MatchFunc func([]byte) bool
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// MatchAll always returns true
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func MatchAll(b []byte) bool {
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return true
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}
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// MatchRange returns true if the first byte of buf is in [lower..upper]
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func MatchRange(lower, upper byte, buf []byte) bool {
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if len(buf) < 1 {
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return false
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}
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b := buf[0]
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return b >= lower && b <= upper
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}
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// MatchFuncs as described in RFC7983
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// https://tools.ietf.org/html/rfc7983
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// +----------------+
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// | [0..3] -+--> forward to STUN
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// | |
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// | [16..19] -+--> forward to ZRTP
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// | |
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// packet --> | [20..63] -+--> forward to DTLS
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// | |
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// | [64..79] -+--> forward to TURN Channel
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// | |
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// | [128..191] -+--> forward to RTP/RTCP
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// +----------------+
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// MatchDTLS is a MatchFunc that accepts packets with the first byte in [20..63]
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// as defied in RFC7983
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func MatchDTLS(b []byte) bool {
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return MatchRange(20, 63, b)
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}
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// MatchSRTPOrSRTCP is a MatchFunc that accepts packets with the first byte in [128..191]
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// as defied in RFC7983
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func MatchSRTPOrSRTCP(b []byte) bool {
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return MatchRange(128, 191, b)
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}
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func isRTCP(buf []byte) bool {
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// Not long enough to determine RTP/RTCP
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if len(buf) < 4 {
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return false
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}
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return buf[1] >= 192 && buf[1] <= 223
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}
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// MatchSRTP is a MatchFunc that only matches SRTP and not SRTCP
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func MatchSRTP(buf []byte) bool {
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return MatchSRTPOrSRTCP(buf) && !isRTCP(buf)
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}
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// MatchSRTCP is a MatchFunc that only matches SRTCP and not SRTP
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func MatchSRTCP(buf []byte) bool {
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return MatchSRTPOrSRTCP(buf) && isRTCP(buf)
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}
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