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mirror of https://github.com/cwinfo/yggdrasil-go.git synced 2024-12-23 12:15:39 +00:00

don't have Conn.Read return an error for temorary crypto failures from e.g. out of order packets, just drop the packet and keep blocking until there's usable traffic

This commit is contained in:
Arceliar 2019-05-31 17:51:01 -05:00
parent 7e837e97e9
commit 1addf08ccd

View File

@ -191,59 +191,64 @@ func (c *Conn) Read(b []byte) (int, error) {
return 0, errors.New("search failed")
}
}
// Wait for some traffic to come through from the session
select {
case <-timer.C:
return 0, ConnError{errors.New("timeout"), true, false, 0}
case p, ok := <-sinfo.recv:
// If the session is closed then do nothing
if !ok {
return 0, errors.New("session is closed")
}
defer util.PutBytes(p.Payload)
var err error
done := make(chan struct{})
workerFunc := func() {
defer close(done)
// If the nonce is bad then drop the packet and return an error
if !sinfo.nonceIsOK(&p.Nonce) {
err = ConnError{errors.New("packet dropped due to invalid nonce"), false, true, 0}
return
}
// Decrypt the packet
bs, isOK := crypto.BoxOpen(&sinfo.sharedSesKey, p.Payload, &p.Nonce)
defer util.PutBytes(bs) // FIXME commenting this out leads to illegal buffer reuse, this implies there's a memory error somewhere and that this is just flooding things out of the finite pool of old slices that get reused
// Check if we were unable to decrypt the packet for some reason and
// return an error if we couldn't
if !isOK {
err = errors.New("packet dropped due to decryption failure")
return
}
// Return the newly decrypted buffer back to the slice we were given
copy(b, bs)
// Trim the slice down to size based on the data we received
if len(bs) < len(b) {
b = b[:len(bs)]
}
// Update the session
sinfo.updateNonce(&p.Nonce)
sinfo.time = time.Now()
sinfo.bytesRecvd += uint64(len(b))
}
// Hand over to the session worker
select { // Send to worker
case sinfo.worker <- workerFunc:
for {
// Wait for some traffic to come through from the session
select {
case <-timer.C:
return 0, ConnError{errors.New("timeout"), true, false, 0}
case p, ok := <-sinfo.recv:
// If the session is closed then do nothing
if !ok {
return 0, errors.New("session is closed")
}
defer util.PutBytes(p.Payload)
var err error
done := make(chan struct{})
workerFunc := func() {
defer close(done)
// If the nonce is bad then drop the packet and return an error
if !sinfo.nonceIsOK(&p.Nonce) {
err = ConnError{errors.New("packet dropped due to invalid nonce"), false, true, 0}
return
}
// Decrypt the packet
bs, isOK := crypto.BoxOpen(&sinfo.sharedSesKey, p.Payload, &p.Nonce)
defer util.PutBytes(bs) // FIXME commenting this out leads to illegal buffer reuse, this implies there's a memory error somewhere and that this is just flooding things out of the finite pool of old slices that get reused
// Check if we were unable to decrypt the packet for some reason and
// return an error if we couldn't
if !isOK {
err = ConnError{errors.New("packet dropped due to decryption failure"), false, true, 0}
return
}
// Return the newly decrypted buffer back to the slice we were given
copy(b, bs)
// Trim the slice down to size based on the data we received
if len(bs) < len(b) {
b = b[:len(bs)]
}
// Update the session
sinfo.updateNonce(&p.Nonce)
sinfo.time = time.Now()
sinfo.bytesRecvd += uint64(len(b))
}
// Hand over to the session worker
select { // Send to worker
case sinfo.worker <- workerFunc:
case <-timer.C:
return 0, ConnError{errors.New("timeout"), true, false, 0}
}
<-done // Wait for the worker to finish, failing this can cause memory errors (util.[Get||Put]Bytes stuff)
// Something went wrong in the session worker so abort
if err != nil {
if ce, ok := err.(*ConnError); ok && ce.Temporary() {
continue
}
return 0, err
}
// If we've reached this point then everything went to plan, return the
// number of bytes we populated back into the given slice
return len(b), nil
}
<-done // Wait for the worker to finish, failing this can cause memory errors (util.[Get||Put]Bytes stuff)
// Something went wrong in the session worker so abort
if err != nil {
return 0, err
}
// If we've reached this point then everything went to plan, return the
// number of bytes we populated back into the given slice
return len(b), nil
}
}