TheArchive/tailscale
1
0
Fork 0
mirror of https://github.com/tailscale/tailscale.git synced 2025-12-03 02:21:58 +00:00
Code Issues Packages Projects Releases Wiki Activity

net/packet: remove {get,put}{16,32} indirection to encoding/binary.

Browse Source 
name              old time/op    new time/op    delta
Decode/tcp4-8       28.8ns ± 2%    13.1ns ± 4%  -54.44%  (p=0.008 n=5+5)
Decode/tcp6-8       20.6ns ± 1%    12.6ns ± 2%  -38.72%  (p=0.008 n=5+5)
Decode/udp4-8       28.2ns ± 1%    12.1ns ± 4%  -57.01%  (p=0.008 n=5+5)
Decode/udp6-8       20.0ns ± 6%    12.1ns ± 2%  -39.38%  (p=0.008 n=5+5)
Decode/icmp4-8      21.7ns ± 2%    11.5ns ± 1%  -47.01%  (p=0.008 n=5+5)
Decode/icmp6-8      14.1ns ± 2%    11.8ns ± 4%  -16.60%  (p=0.008 n=5+5)
Decode/unknown-8    9.43ns ± 2%    9.30ns ± 3%     ~     (p=0.222 n=5+5)

Signed-off-by: David Anderson <danderson@tailscale.com>
This commit is contained in:
David Anderson
2020-11-10 19:09:47 -08:00
committed by Dave Anderson
parent 55b1221db2
commit 22bf48f37c
4 changed files with 39 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
net/packet/packet.go
View File

@@ -21,14 +21,6 @@ const (
TCPSynAck = TCPSyn | TCPAck
)
var (
get16 = binary.BigEndian.Uint16
get32 = binary.BigEndian.Uint32
put16 = binary.BigEndian.PutUint16
put32 = binary.BigEndian.PutUint32
)
// Parsed is a minimal decoding of a packet suitable for use in filters.
//
// In general, it only supports IPv4. The IPv6 parsing is very minimal.
@@ -114,7 +106,7 @@ func ipChecksum(b []byte) uint16 {
i := 0
n := len(b)
for n >= 2 {
ac += uint32(get16(b[i : i+2]))
ac += uint32(binary.BigEndian.Uint16(b[i : i+2]))
n -= 2
i += 2
}
@@ -161,7 +153,7 @@ func (q *Parsed) decode4(b []byte) {
// Check that it's IPv4.
q.IPProto = IPProto(b[9])
q.length = int(get16(b[2:4]))
q.length = int(binary.BigEndian.Uint16(b[2:4]))
if len(b) < q.length {
// Packet was cut off before full IPv4 length.
q.IPProto = Unknown
@@ -169,8 +161,8 @@ func (q *Parsed) decode4(b []byte) {
}
// If it's valid IPv4, then the IP addresses are valid
q.SrcIP4 = IP4(get32(b[12:16]))
q.DstIP4 = IP4(get32(b[16:20]))
q.SrcIP4 = IP4(binary.BigEndian.Uint32(b[12:16]))
q.DstIP4 = IP4(binary.BigEndian.Uint32(b[16:20]))
q.subofs = int((b[0] & 0x0F) << 2)
sub := b[q.subofs:]
@@ -187,7 +179,7 @@ func (q *Parsed) decode4(b []byte) {
// zero reason to send such a short first fragment, so we can treat
// it as Unknown. We can also treat any subsequent fragment that starts
// at such a low offset as Unknown.
fragFlags := get16(b[6:8])
fragFlags := binary.BigEndian.Uint16(b[6:8])
moreFrags := (fragFlags & 0x20) != 0
fragOfs := fragFlags & 0x1FFF
if fragOfs == 0 {
@@ -215,8 +207,8 @@ func (q *Parsed) decode4(b []byte) {
q.IPProto = Unknown
return
}
q.SrcPort = get16(sub[0:2])
q.DstPort = get16(sub[2:4])
q.SrcPort = binary.BigEndian.Uint16(sub[0:2])
q.DstPort = binary.BigEndian.Uint16(sub[2:4])
q.TCPFlags = sub[13] & 0x3F
headerLength := (sub[12] & 0xF0) >> 2
q.dataofs = q.subofs + int(headerLength)
@@ -226,8 +218,8 @@ func (q *Parsed) decode4(b []byte) {
q.IPProto = Unknown
return
}
q.SrcPort = get16(sub[0:2])
q.DstPort = get16(sub[2:4])
q.SrcPort = binary.BigEndian.Uint16(sub[0:2])
q.DstPort = binary.BigEndian.Uint16(sub[2:4])
q.dataofs = q.subofs + udpHeaderLength
return
default:
@@ -261,7 +253,7 @@ func (q *Parsed) decode6(b []byte) {
}
q.IPProto = IPProto(b[6])
q.length = int(get16(b[4:6])) + ip6HeaderLength
q.length = int(binary.BigEndian.Uint16(b[4:6])) + ip6HeaderLength
if len(b) < q.length {
// Packet was cut off before the full IPv6 length.
q.IPProto = Unknown
@@ -300,8 +292,8 @@ func (q *Parsed) decode6(b []byte) {
q.IPProto = Unknown
return
}
q.SrcPort = get16(sub[0:2])
q.DstPort = get16(sub[2:4])
q.SrcPort = binary.BigEndian.Uint16(sub[0:2])
q.DstPort = binary.BigEndian.Uint16(sub[2:4])
q.TCPFlags = sub[13] & 0x3F
headerLength := (sub[12] & 0xF0) >> 2
q.dataofs = q.subofs + int(headerLength)
@@ -311,8 +303,8 @@ func (q *Parsed) decode6(b []byte) {
q.IPProto = Unknown
return
}
q.SrcPort = get16(sub[0:2])
q.DstPort = get16(sub[2:4])
q.SrcPort = binary.BigEndian.Uint16(sub[0:2])
q.DstPort = binary.BigEndian.Uint16(sub[2:4])
q.dataofs = q.subofs + udpHeaderLength
default:
q.IPProto = Unknown
@@ -324,7 +316,7 @@ func (q *Parsed) IP4Header() IP4Header {
if q.IPVersion != 4 {
panic("IP4Header called on non-IPv4 Parsed")
}
ipid := get16(q.b[4:6])
ipid := binary.BigEndian.Uint16(q.b[4:6])
return IP4Header{
IPID: ipid,
IPProto: q.IPProto,