mirror of
https://github.com/soypat/lneto.git
synced 2026-08-08 17:03:40 +00:00
Pat Whittingslow
7698b9fb81
* do not rely on unspecified Go behaviour; fix TCP ring buffer bug * even more stricter error handling on tcp connections * stricter lock copying in tcp.Conn, even though likely not a problem * add listener and tcp pool logging * forgot reqAddr unused * add logging to TCPConn and friends
59 lines
1.2 KiB
Go
59 lines
1.2 KiB
Go
package internal
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import (
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"encoding/binary"
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"errors"
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)
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var (
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errUnsupportedIP = errors.New("unsupported IP version")
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errInvalidIPVersionToSetAddr = errors.New("invalid ip version to setDstAddr")
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)
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func GetIPAddr(buf []byte) (src, dst []byte, id, ipEndOff uint16, err error) {
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b0 := buf[0]
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version := b0 >> 4
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switch version {
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case 4:
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ihl := b0 & 0xf
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ipEndOff = 4 * uint16(ihl)
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id = binary.BigEndian.Uint16(buf[4:6])
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src = buf[12:16]
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dst = buf[16:20]
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case 6:
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src = buf[8:24]
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dst = buf[24:40]
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ipEndOff = 40
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default:
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err = errUnsupportedIP
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}
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return src, dst, id, ipEndOff, err
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}
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func SetIPAddrs(buf []byte, id uint16, src, dst []byte) (err error) {
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var dstaddr, srcaddr []byte
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version := buf[0] >> 4
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switch version {
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case 4:
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srcaddr = buf[12:16]
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dstaddr = buf[16:20]
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if id > 0 {
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binary.BigEndian.PutUint16(buf[4:6], id)
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}
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case 6:
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srcaddr = buf[8:24]
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dstaddr = buf[24:40]
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default:
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return errUnsupportedIP
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}
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if src != nil && len(srcaddr) != len(src) {
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return errors.New("mismatched length of ip src addr")
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}
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if dst != nil && len(dstaddr) != len(dst) {
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return errors.New("mismatched length of ip dst addr")
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}
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copy(srcaddr, src)
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copy(dstaddr, dst)
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return nil
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}
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