boot_net: Various TCP fixes

Don't enqueue a packet whose sequence number matches the first one in queue
or is between the next and the acknowledged on. This would lead to packet
duplication in the queue and leftovers after dequeuing.

Optimize calculation of acknowledgement number for out-of-order reception.
If a single missing packet arrived, this could have resulted in a timeout
depending on the window size.

In case the connection is closed, do dequeue remaining packets. This would
have caused a read error after a unidirectional FIN.

Prepare a dynamic window size calculation.

Do checksum calculation before attempting to trace packet contents. I have
seen a few and couldn't spot an error in the checksum calculation.

More fine-grained control over trace output.
Trace the Maximum Segment Size option if present; break after End of Options.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38535 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Prepare socket-specific TCP window size

Pass the desired window size from the socket to the service.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38530 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: TCP and UDP style cleanup

Remove superfluous comments.
Adjust spacing and initializer indentation.
Make NULL pointer checks explicit.
Don't assign in if-clause.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38529 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Fix TCP memory leaks

In some error conditions the packet would have been leaked.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38503 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Mute some TCP debug output

Trace packet dequeing only when asked to.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38483 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Use real_time_clock_usecs() for TCP

Initialize the PRNG seed for the sequence number with real_time_clock_usecs()
rather than system_time(). The remaining uses of system_time() for timeout
calculation match UDP.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38482 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Add TCP support

Modelled after UDP, add limited TCP support to the boot net stack. The socket
works by queuing received packets as well as sent packets that have not yet
been ACK'ed. Some known issues are documented, especially there's only limited
congestion control. I.e., we send immediately and in unlimited quantity, thus
its use should be restricted to local networks, and due to a fixed window size
there is potential for our socket being overrun with data packets before they
are read. Some corner cases like wrapping sequence numbers may cause a timeout.

The TCP implementation is based on Andrew S. Tanenbaum's "Computer Networks",
4th ed., as well as lecture notes from Prof. W. Effelsberg, the relevant RFCs
and Wikipedia. The pseudo-random number Galois LFSR used for the sequence
number was suggested by Endre Varga.

Since the code is unlikely to get much smaller, better merge it now so that
subsequent changes get easier to review. No platform actively uses TCP sockets
yet, and the receiving code has been reviewed for endianness issues and should
terminate okay after verifying the checksum if no sockets are open.
Based on a version tested with custom code (#5240) as well as with iSCSI.
Compile-tested boot_loader_openfirmware, pxehaiku-loader with gcc4 and
haiku_loader with gcc2. Closes ticket #5240.

Changes from #5240 proposed patch:
* Various bug fixes related to queuing, some memory leaks fixed.
* Never bump the sequence number when dequeuing a packet. It's done afterwards.
* Don't bump the sequence number again when resending the queue or ACK'ing.
* Aggressively ACK while waiting for packets.
* Don't queue sent ACK-only packets.
* More trace output, esp. for queue inspection.
* Adapted use of TCP header flags to r38434.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38472 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Various TCP fixes

Don't enqueue a packet whose sequence number matches the first one in queue
or is between the next and the acknowledged on. This would lead to packet
duplication in the queue and leftovers after dequeuing.

Optimize calculation of acknowledgement number for out-of-order reception.
If a single missing packet arrived, this could have resulted in a timeout
depending on the window size.

In case the connection is closed, do dequeue remaining packets. This would
have caused a read error after a unidirectional FIN.

Prepare a dynamic window size calculation.

Do checksum calculation before attempting to trace packet contents. I have
seen a few and couldn't spot an error in the checksum calculation.

More fine-grained control over trace output.
Trace the Maximum Segment Size option if present; break after End of Options.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38535 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Prepare socket-specific TCP window size

Pass the desired window size from the socket to the service.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38530 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: TCP and UDP style cleanup

Remove superfluous comments.
Adjust spacing and initializer indentation.
Make NULL pointer checks explicit.
Don't assign in if-clause.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38529 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Fix TCP memory leaks

In some error conditions the packet would have been leaked.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38503 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Mute some TCP debug output

Trace packet dequeing only when asked to.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38483 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Use real_time_clock_usecs() for TCP

Initialize the PRNG seed for the sequence number with real_time_clock_usecs()
rather than system_time(). The remaining uses of system_time() for timeout
calculation match UDP.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38482 a95241bf-73f2-0310-859d-f6bbb57e9c96

boot_net: Add TCP support

Modelled after UDP, add limited TCP support to the boot net stack. The socket
works by queuing received packets as well as sent packets that have not yet
been ACK'ed. Some known issues are documented, especially there's only limited
congestion control. I.e., we send immediately and in unlimited quantity, thus
its use should be restricted to local networks, and due to a fixed window size
there is potential for our socket being overrun with data packets before they
are read. Some corner cases like wrapping sequence numbers may cause a timeout.

The TCP implementation is based on Andrew S. Tanenbaum's "Computer Networks",
4th ed., as well as lecture notes from Prof. W. Effelsberg, the relevant RFCs
and Wikipedia. The pseudo-random number Galois LFSR used for the sequence
number was suggested by Endre Varga.

Since the code is unlikely to get much smaller, better merge it now so that
subsequent changes get easier to review. No platform actively uses TCP sockets
yet, and the receiving code has been reviewed for endianness issues and should
terminate okay after verifying the checksum if no sockets are open.
Based on a version tested with custom code (#5240) as well as with iSCSI.
Compile-tested boot_loader_openfirmware, pxehaiku-loader with gcc4 and
haiku_loader with gcc2. Closes ticket #5240.

Changes from #5240 proposed patch:
* Various bug fixes related to queuing, some memory leaks fixed.
* Never bump the sequence number when dequeuing a packet. It's done afterwards.
* Don't bump the sequence number again when resending the queue or ACK'ing.
* Aggressively ACK while waiting for packets.
* Don't queue sent ACK-only packets.
* More trace output, esp. for queue inspection.
* Adapted use of TCP header flags to r38434.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38472 a95241bf-73f2-0310-859d-f6bbb57e9c96