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author | Christopher Speller <crspeller@gmail.com> | 2016-10-03 16:03:15 -0400 |
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committer | GitHub <noreply@github.com> | 2016-10-03 16:03:15 -0400 |
commit | 8f91c777559748fa6e857d9fc1f4ae079a532813 (patch) | |
tree | 190f7cef373764a0d47a91045fdb486ee3d6781d /vendor/golang.org/x/net/ipv4/header.go | |
parent | 5f8e5c401bd96cba9a98b2db02d72f9cbacb0103 (diff) | |
download | chat-8f91c777559748fa6e857d9fc1f4ae079a532813.tar.gz chat-8f91c777559748fa6e857d9fc1f4ae079a532813.tar.bz2 chat-8f91c777559748fa6e857d9fc1f4ae079a532813.zip |
Adding ability to serve TLS directly from Mattermost server (#4119)
Diffstat (limited to 'vendor/golang.org/x/net/ipv4/header.go')
-rw-r--r-- | vendor/golang.org/x/net/ipv4/header.go | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/ipv4/header.go b/vendor/golang.org/x/net/ipv4/header.go new file mode 100644 index 000000000..363d9c21a --- /dev/null +++ b/vendor/golang.org/x/net/ipv4/header.go @@ -0,0 +1,132 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ipv4 + +import ( + "encoding/binary" + "fmt" + "net" + "runtime" + "syscall" +) + +const ( + Version = 4 // protocol version + HeaderLen = 20 // header length without extension headers + maxHeaderLen = 60 // sensible default, revisit if later RFCs define new usage of version and header length fields +) + +type HeaderFlags int + +const ( + MoreFragments HeaderFlags = 1 << iota // more fragments flag + DontFragment // don't fragment flag +) + +// A Header represents an IPv4 header. +type Header struct { + Version int // protocol version + Len int // header length + TOS int // type-of-service + TotalLen int // packet total length + ID int // identification + Flags HeaderFlags // flags + FragOff int // fragment offset + TTL int // time-to-live + Protocol int // next protocol + Checksum int // checksum + Src net.IP // source address + Dst net.IP // destination address + Options []byte // options, extension headers +} + +func (h *Header) String() string { + if h == nil { + return "<nil>" + } + return fmt.Sprintf("ver=%d hdrlen=%d tos=%#x totallen=%d id=%#x flags=%#x fragoff=%#x ttl=%d proto=%d cksum=%#x src=%v dst=%v", h.Version, h.Len, h.TOS, h.TotalLen, h.ID, h.Flags, h.FragOff, h.TTL, h.Protocol, h.Checksum, h.Src, h.Dst) +} + +// Marshal returns the binary encoding of the IPv4 header h. +func (h *Header) Marshal() ([]byte, error) { + if h == nil { + return nil, syscall.EINVAL + } + if h.Len < HeaderLen { + return nil, errHeaderTooShort + } + hdrlen := HeaderLen + len(h.Options) + b := make([]byte, hdrlen) + b[0] = byte(Version<<4 | (hdrlen >> 2 & 0x0f)) + b[1] = byte(h.TOS) + flagsAndFragOff := (h.FragOff & 0x1fff) | int(h.Flags<<13) + switch runtime.GOOS { + case "darwin", "dragonfly", "freebsd", "netbsd": + nativeEndian.PutUint16(b[2:4], uint16(h.TotalLen)) + nativeEndian.PutUint16(b[6:8], uint16(flagsAndFragOff)) + default: + binary.BigEndian.PutUint16(b[2:4], uint16(h.TotalLen)) + binary.BigEndian.PutUint16(b[6:8], uint16(flagsAndFragOff)) + } + binary.BigEndian.PutUint16(b[4:6], uint16(h.ID)) + b[8] = byte(h.TTL) + b[9] = byte(h.Protocol) + binary.BigEndian.PutUint16(b[10:12], uint16(h.Checksum)) + if ip := h.Src.To4(); ip != nil { + copy(b[12:16], ip[:net.IPv4len]) + } + if ip := h.Dst.To4(); ip != nil { + copy(b[16:20], ip[:net.IPv4len]) + } else { + return nil, errMissingAddress + } + if len(h.Options) > 0 { + copy(b[HeaderLen:], h.Options) + } + return b, nil +} + +// ParseHeader parses b as an IPv4 header. +func ParseHeader(b []byte) (*Header, error) { + if len(b) < HeaderLen { + return nil, errHeaderTooShort + } + hdrlen := int(b[0]&0x0f) << 2 + if hdrlen > len(b) { + return nil, errBufferTooShort + } + h := &Header{ + Version: int(b[0] >> 4), + Len: hdrlen, + TOS: int(b[1]), + ID: int(binary.BigEndian.Uint16(b[4:6])), + TTL: int(b[8]), + Protocol: int(b[9]), + Checksum: int(binary.BigEndian.Uint16(b[10:12])), + Src: net.IPv4(b[12], b[13], b[14], b[15]), + Dst: net.IPv4(b[16], b[17], b[18], b[19]), + } + switch runtime.GOOS { + case "darwin", "dragonfly", "netbsd": + h.TotalLen = int(nativeEndian.Uint16(b[2:4])) + hdrlen + h.FragOff = int(nativeEndian.Uint16(b[6:8])) + case "freebsd": + h.TotalLen = int(nativeEndian.Uint16(b[2:4])) + if freebsdVersion < 1000000 { + h.TotalLen += hdrlen + } + h.FragOff = int(nativeEndian.Uint16(b[6:8])) + default: + h.TotalLen = int(binary.BigEndian.Uint16(b[2:4])) + h.FragOff = int(binary.BigEndian.Uint16(b[6:8])) + } + h.Flags = HeaderFlags(h.FragOff&0xe000) >> 13 + h.FragOff = h.FragOff & 0x1fff + if hdrlen-HeaderLen > 0 { + h.Options = make([]byte, hdrlen-HeaderLen) + copy(h.Options, b[HeaderLen:]) + } + return h, nil +} |