Files
go-i2p/lib/transport/noise/read_session.go
2024-10-03 22:36:23 -04:00

93 lines
2.3 KiB
Go

package noise
import (
"errors"
"sync/atomic"
log "github.com/sirupsen/logrus"
)
func (c *NoiseSession) Read(b []byte) (int, error) {
// interlock with Close below
for {
x := atomic.LoadInt32(&c.activeCall)
if x&1 != 0 {
log.WithFields(log.Fields{
"at": "(NoiseSession) Read",
"reason": "session is closed",
}).Error("session is closed")
return 0, errors.New("session is closed")
}
if atomic.CompareAndSwapInt32(&c.activeCall, x, x+2) {
defer atomic.AddInt32(&c.activeCall, -2)
break
}
}
if !c.handshakeComplete {
if err := c.RunIncomingHandshake(); err != nil {
return 0, err
}
}
c.Mutex.Lock()
defer c.Mutex.Unlock()
if !c.handshakeComplete {
return 0, errors.New("internal error")
}
n, err := c.readPacketLocked(b)
return n, err
}
func (c *NoiseSession) decryptPacket(data []byte) (int, []byte, error) {
if c.CipherState == nil {
return 0, nil, errors.New("CipherState is nil")
}
// Decrypt
decryptedData, err := c.CipherState.Decrypt(nil, nil, data)
if err != nil {
return 0, nil, err
}
m := len(decryptedData)
return m, decryptedData, nil
/*packet := c.InitializePacket()
maxPayloadSize := c.maxPayloadSizeForRead(packet)
if m > int(maxPayloadSize) {
m = int(maxPayloadSize)
}
if c.CipherState != nil {
////fmt.Println("writing encrypted packet:", m)
packet.reserve(uint16Size + uint16Size + m + macSize)
packet.resize(uint16Size + uint16Size + m)
copy(packet.data[uint16Size+uint16Size:], data[:m])
binary.BigEndian.PutUint16(packet.data[uint16Size:], uint16(m))
//fmt.Println("encrypt size", uint16(m))
} else {
packet.resize(len(packet.data) + len(data))
copy(packet.data[uint16Size:len(packet.data)], data[:m])
binary.BigEndian.PutUint16(packet.data, uint16(len(data)))
}
b := c.encryptIfNeeded(packet)*/
//c.freeBlock(packet)
}
func (c *NoiseSession) readPacketLocked(data []byte) (int, error) {
var n int
if len(data) == 0 { //special case to answer when everything is ok during handshake
if _, err := c.Conn.Read(make([]byte, 2)); err != nil {
return 0, err
}
}
for len(data) > 0 {
m, b, err := c.encryptPacket(data)
if err != nil {
return 0, err
}
if n, err := c.Conn.Read(b); err != nil {
return n, err
} else {
n += m
data = data[m:]
}
}
return n, nil
}