TODO: Pasting more than 1025 bytes into a Sortix ssh session disconnects it.
TODO: ssh to localhost from tty is corrupted
TODO: /etc/ssh*_config should be in /etc/default/
This commit is based on work by Meisaka Yukara <Meisaka.Yukara@gmail.com>
contributed as the commit bbf7f1e8a5238a2bd1fe8eb1d2cc5c9c2421e2c4. See the
individual file headers for which files contain remnants of this work.
This change adds all the kernel parts of a network stack. The network stack
is partial but implements many of the important parts.
Add if(4) network interface abstraction. Network interfaces are registered
in a global list that can be iterated and each assigned an unique integer
identifier.
Add reference counted packets with a cache that recycles recent packets.
Add support for lo(4) loopback and ether(4) ethernet network interfaces.
The /dev/lo0 loopback device is created automatically on boot.
Add arp(4) address resolution protocol driver for translation of inet(4)
network layer addresses into ether(4) link layer addresses. arp(4) entries
are cached and evicted from the cache when needed or when the entry has not
been used for a while. The cache is limited to 256 entries for now.
Add ip(4) internet protocol version 4 support. IP fragmentation and options
are not implemented yet.
Add tcp(4) transmission control protocol sockets for a reliable transport
layer protocol that provides a reliable byte stream connection between two
hosts. The implementation is incomplete and does not yet implement out of
band data, options, and high performance extensions.
Add udp(4) user datagram protocol sockets for a connectionless transport
layer that provides best-effort delivery of datagrams.
Add ping(4) sockets for a best-effort delivery echo of datagrams.
Change type of sa_family_t from unsigned short to uint16_t.
Add --disable-network-drivers to the kernel(7) options and expose it with a
bootloader menu. tix-iso-bootconfig can set this option by default.
Import CRC32 code from libz for the Ethernet checksum.
This is a compatible ABI change that adds features to socket(2) (AF_INET,
IPPROTO_TCP, IPPROTO_UDP, IPPROTO_PING), the ioctls for if(4), socket
options, and the lo0 loopback interface.
The .init section for global constructors in the kernel is unused at the
moment as the _init function is never invoked, but its existence means
it got linked at 128 MiB on i686. This address isn't mapped by the
kernel and the bootloader requires the machine to have that much
physical memory. Unfortunately that meant the i686 build didn't work on
machines with less than 129 MiB of memory.
Previously Sortix would initialize SSE unconditionally as part of the
boot process. Since earlier i686 CPUs like Pentium 2 did not include
SSE, Sortix would not run on them. With this SSE is only enabled for
CPUs that include it, which should theoretically allow Sortix to boot on
all i686 CPUs. Additionally, this removes -msse -msse2 compiler flags
from trianglix/Makefile.
This change refactors the Unix socket / pipe backend to have a ring buffer
containing segments, where each segment has an optional leading ancillary
buffer containing control messages followed by a normal data buffer.
The SCM_RIGHTS control message has been implemented which transfers file
descriptors to the receiving process. File descriptors are reference counted
and cycles are prevented using the following restrictions:
1) Unix sockets cannot be sent on themselves (on either end).
2) Unix sockets themselves being sent cannot be sent on.
3) Unix sockets cannot send a Unix socket being sent on.
This is a compatible ABI change.
The file descriptor table now allows reserving room for multiple file
descriptors without assigning their numbers. This functionality means
any error conditions happen up front and the subsequent number
assignment will never fail.
This change uses the new functionality to fix troublesome error handling
when allocating multiple file descriptors. One pty allocation error path
was even wrong.
There were subtle race conditions where one (kernel) thread may have
allocated one file descriptor, and another thread spuciously replaces it
with something else, and then the second file descriptor allocation
failed in the first thread, and it closes the first file descriptor now
pointing to a different file description. This case seems harmless but
it's not a great class of bugs to exist in the first place. The new
behavior means the file descriptions appear in the file descriptor table
without fail and never needs to be cleaned up midway and is certainly
immune to shenangians from other threads.
Reviewed-by: Pedro Falcato <pedro.falcato@gmail.com>
Jonas 'Sortie' Termansen
auronandace
Juhani Krekelä