/usr/share/gocode/src/github.com/twstrike/otr3/tlv.go is in golang-github-twstrike-otr3-dev 0.0~git20161015.0.744856d-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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import "bytes"
const tlvHeaderLength = 4
const (
tlvTypePadding = uint16(0x00)
tlvTypeDisconnected = uint16(0x01)
tlvTypeSMP1 = uint16(0x02)
tlvTypeSMP2 = uint16(0x03)
tlvTypeSMP3 = uint16(0x04)
tlvTypeSMP4 = uint16(0x05)
tlvTypeSMPAbort = uint16(0x06)
tlvTypeSMP1WithQuestion = uint16(0x07)
tlvTypeExtraSymmetricKey = uint16(0x08)
)
type tlvHandler func(*Conversation, tlv, dataMessageExtra) (*tlv, error)
var tlvHandlers = make([]tlvHandler, 9)
func initTLVHandlers() {
tlvHandlers[tlvTypePadding] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processPaddingTLV(t, x)
}
tlvHandlers[tlvTypeDisconnected] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processDisconnectedTLV(t, x)
}
tlvHandlers[tlvTypeSMP1] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeSMP2] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeSMP3] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeSMP4] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeSMPAbort] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeSMP1WithQuestion] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processSMPTLV(t, x)
}
tlvHandlers[tlvTypeExtraSymmetricKey] = func(c *Conversation, t tlv, x dataMessageExtra) (*tlv, error) {
return c.processExtraSymmetricKeyTLV(t, x)
}
}
func messageHandlerForTLV(t tlv) (tlvHandler, error) {
if t.tlvType >= uint16(len(tlvHandlers)) {
return nil, newOtrError("unexpected TLV type")
}
return tlvHandlers[t.tlvType], nil
}
type tlv struct {
tlvType uint16
tlvLength uint16
tlvValue []byte
}
func (c tlv) serialize() []byte {
out := appendShort([]byte{}, c.tlvType)
out = appendShort(out, c.tlvLength)
return append(out, c.tlvValue...)
}
func (c *tlv) deserialize(tlvsBytes []byte) error {
var ok bool
tlvsBytes, c.tlvType, ok = extractShort(tlvsBytes)
if !ok {
return newOtrError("wrong tlv type")
}
tlvsBytes, c.tlvLength, ok = extractShort(tlvsBytes)
if !ok {
return newOtrError("wrong tlv length")
}
if len(tlvsBytes) < int(c.tlvLength) {
return newOtrError("wrong tlv value")
}
c.tlvValue = tlvsBytes[:int(c.tlvLength)]
return nil
}
func (c tlv) isSMPMessage() bool {
return c.tlvType >= tlvTypeSMP1 && c.tlvType <= tlvTypeSMP1WithQuestion
}
func (c tlv) smpMessage() (smpMessage, bool) {
switch c.tlvType {
case tlvTypeSMP1:
return toSmpMessage1(c)
case tlvTypeSMP1WithQuestion:
return toSmpMessage1Q(c)
case tlvTypeSMP2:
return toSmpMessage2(c)
case tlvTypeSMP3:
return toSmpMessage3(c)
case tlvTypeSMP4:
return toSmpMessage4(c)
case tlvTypeSMPAbort:
return toSmpMessageAbort(c)
}
return nil, false
}
func toSmpMessage1(t tlv) (msg smp1Message, ok bool) {
_, mpis, ok := extractMPIs(t.tlvValue)
if !ok || len(mpis) < 6 {
return msg, false
}
msg.g2a = mpis[0]
msg.c2 = mpis[1]
msg.d2 = mpis[2]
msg.g3a = mpis[3]
msg.c3 = mpis[4]
msg.d3 = mpis[5]
return msg, true
}
func toSmpMessage1Q(t tlv) (msg smp1Message, ok bool) {
nulPos := bytes.IndexByte(t.tlvValue, 0)
if nulPos == -1 {
return msg, false
}
question := string(t.tlvValue[:nulPos])
t.tlvValue = t.tlvValue[(nulPos + 1):]
msg, ok = toSmpMessage1(t)
msg.hasQuestion = true
msg.question = question
return msg, ok
}
func toSmpMessage2(t tlv) (msg smp2Message, ok bool) {
_, mpis, ok := extractMPIs(t.tlvValue)
if !ok || len(mpis) < 11 {
return msg, false
}
msg.g2b = mpis[0]
msg.c2 = mpis[1]
msg.d2 = mpis[2]
msg.g3b = mpis[3]
msg.c3 = mpis[4]
msg.d3 = mpis[5]
msg.pb = mpis[6]
msg.qb = mpis[7]
msg.cp = mpis[8]
msg.d5 = mpis[9]
msg.d6 = mpis[10]
return msg, true
}
func toSmpMessage3(t tlv) (msg smp3Message, ok bool) {
_, mpis, ok := extractMPIs(t.tlvValue)
if !ok || len(mpis) < 8 {
return msg, false
}
msg.pa = mpis[0]
msg.qa = mpis[1]
msg.cp = mpis[2]
msg.d5 = mpis[3]
msg.d6 = mpis[4]
msg.ra = mpis[5]
msg.cr = mpis[6]
msg.d7 = mpis[7]
return msg, true
}
func toSmpMessage4(t tlv) (msg smp4Message, ok bool) {
_, mpis, ok := extractMPIs(t.tlvValue)
if !ok || len(mpis) < 3 {
return msg, false
}
msg.rb = mpis[0]
msg.cr = mpis[1]
msg.d7 = mpis[2]
return msg, true
}
func toSmpMessageAbort(t tlv) (msg smpMessageAbort, ok bool) {
return msg, true
}
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