method avoided all race conditions, but suffered from
sometimes running out of buffer space if enough clients
were piled up at the same time.
Now, the client pushes the link descriptor, one end of a
socketpair() and the ppp version via sendmsg() at the
server. The server replies with a pid. The client then
transfers any link lock with uu_lock_txfr() and writev()s
the actual link contents. The socketpair is now the only
place we need to have large socket buffers and the bind()ed
socket can keep the default 4k buffer while still handling
around 90 racing clients.
Previously, ppp attempted to bind() to a local domain tcp socket
based on the peer authname & enddisc. If it succeeded, it listen()ed
and became MP server. If it failed, it connect()ed and became MP
client. The server then select()ed on the descriptor, accept()ed
it and wrote its pid to it then read the link data & link file descriptor,
and finally sent an ack (``!''). The client would read() the server
pid, transfer the link lock to that pid, send the link data & descriptor
and read the ack. It would then close the descriptor and clean up.
There was a race between the bind() and listen() where someone could
attempt to connect() and fail.
This change removes the race. Now ppp makes the RCVBUF big enough on a
socket descriptor and attempts to bind() to a local domain *udp* socket
(same name as before). If it succeeds, it becomes MP server. If it
fails, it sets the SNDBUF and connect()s, becoming MP client. The server
select()s on the descriptor and recvmsg()s the message, insisting on at
least two descriptors (plus the link data). It uses the second descriptor
to write() its pid then read()s an ack (``!''). The client creates a
socketpair() and sendmsg()s the link data, link descriptor and one of
the socketpair descriptors. It then read()s the server pid from the
other socketpair descriptor, transfers any locks and write()s an ack.
Now, there can be no race, and a connect() failure indicates a stale
socket file.
This also fixes MP ppp over ethernet, where the struct msghdr was being
misconstructed when transferring the control socket descriptor.
Also, if we fail to send the link, don't hang around in a ``session
owner'' state, just do the setsid() and fork() if it's required to
disown a tty.
UDP idea suggested by: Chris Bennet from Mindspring at FreeBSDCon
ip_tos == IPTOS_LOWDELAY now get precidence over urgent
packets with ip_tos != IPTOS_LOWDELAY and non-urgent packets
with ip_tos == IPTOS_LOWDELAY.
Enhance the ``set urgent'' syntax to allow for urgent UDP
packets as well as urgent TCP packets.
(LCP/CCP/IPCP), one for urgent IP traffic and one for
everything else.
o Add the ``set urgent'' command for adjusting the list of
urgent port numbers. The default urgent ports are 21, 22,
23, 513, 514, 543 and 544 (Ports 80 and 81 have been
removed from the default priority list).
o Increase the buffered packet threshold from 20 to 30.
o Report the number of packets in the IP output queue and the
list of urgent ports under ``show ipcp''.
that ppp stays in the foreground.
o Add the -quiet switch to quieten ppps startup
o Add the -nat flag and discourage the use of the -alias flag. Both do
the same thing.
o Correct some nat usage strings.
o Change the internal ``alias'' command to ``nat''.
o If we're using RADIUS and the RADIUS mtu is less than our
peers mru/mrru, reduce our mtu to this value for NetBSD too.
o Make struct throughput's sample period dynamic and tweak the ppp
version number to reflect the extra stuff being passed through
the local domain socket as a result (MP mode).
o Measure the current throughput based on the number of samples actually
taken rather than on the full sample period.
o Keep the throughput statisics persistent while being passed to
another ppp invocation through the local domain socket.
o When showing throughput statistics after the timer has stopped, use
the stopped time for overall calculations, not the current time.
Also show the stopped time and how long the current throughput has
been sampled for.
o Use time() consistently in throughput.c
o Tighten up the ``show bundle'' output.
o Introduce the ``set bandwidth'' command.
o Rewrite the ``set autoload'' command. It now takes three arguments
and works based on a rolling bundle throughput average compared against
the theoretical bundle bandwidth over a given period (read: it's now
functional).
mode by padding out the ``struct device'' to the maximum
device size.
Bump the ppp version number to indicate the transfer format
change.
This should make MP over tty and udp devices functional again.
being the same as the previous (still supported) ``host:port''
syntax for tcp socket devices.
A udp device uses synchronous ppp rather than async, and avoids
the double-retransmit overhead that comes with ppp over tcp (it's
usually a bad idea to transport IP over a reliable transport that
itself is using an unreliable transport). PPP over UDP provides
througput of ** 1.5Mb per second ** with all compression disabled,
maxing out a PPro/200 when running ppp twice, back-to-back.
This proves that PPPoE is plausable in userland....
This change adds a few more handler functions to struct device and
allows derivations of struct device (which may contain their own
data etc) to pass themselves through the unix domain socket for MP.
** At last **, struct physical has lost all the tty crud !
iov2physical() is now smart enough to restore the correct stack of
layers so that MP servers will work again.
The version number has bumped as our MP link transfer contents have
changed (they now may contain a `struct device').
Don't extract the protocol twice in MP mode (resulting in protocol
rejects for every MP packet). This was broken with my original
layering changes.
Add ``Physical'' and ``Sync'' log levels for logging the relevent
raw packets and add protocol-tracking LogDEBUG stuff in various
LayerPush & LayerPull functions.
Assign our physical device name for incoming tcp connections by
calling getpeername().
Assign our physical device name for incoming udp connections from
the address retrieved by the first recvfrom().
the layering.
We now ``stack'' layers as soon as we open the device (when we figure
out what we're dealing with). A static set of `dispatch' routines are
also declared for dealing with incoming packets after they've been
`pulled' up through the stacked layers.
Physical devices are now assigned handlers based on the device type
when they're opened. For the moment there are three device types;
ttys, execs and tcps.
o Increment version number to 2.2
o Make an entry in [uw]tmp for non-tty -direct invocations (after
pap/chap authentication).
o Make throughput counters quad_t's
o Account for the absolute number of mbuf malloc()s and free()s in
``show mem''.
o ``show modem'' becomes ``show physical''.
This was pretty harmless as netmasks on a POINTOPOINT
interface are pretty much ignored, but it looked funny.
Mention the configured netmask in ``show ipcp''.
Describe in more detail what a proxy arp entry is.
that are made in each of the FSMs (LCP, CCP & IPCP) and the
number of REQs/Challenges for PAP/CHAP by accepting more arguments
in the ``set {c,ip,l}cpretry'' and ``set {ch,p}apretry'' commands.
Change the non-convergence thresholds to 3 times the number of configured
REQ tries (rather than the previous fixed ``10''). We now notice
repeated NAKs and REJs rather than just REQs.
Don't suggest that CHAP 0x05 isn't supported when it's not configured.
Fix some bugs that expose themselves with smaller numbers of retries:
o Handle instantaneous disconnects (set device /dev/null) correctly
by stopping all fsm timers in fsm2initial.
o Don't forget to uu_unlock() devices that are files but are not
ttys (set device /dev/zero).
Fix a *HORRENDOUS* bug in RFC1661 (already fixed for an Open event in state
``Closed''):
According to the state transition table, a RCR+ or RCR- received in
the ``Stopped'' state are supposed to InitRestartCounter, SendConfigReq
and SendConfig{Ack,Nak}. However, in ``Stopped'', we haven't yet
done a TLS (or the last thing we did is a TLF). We must therefore
do the TLS at this point !
This was never noticed before because LCP and CCP used not use
LayerStart() for anything interesting, and IPCP tends to go into
Stopped then get a Down because of an LCP RTR rather than getting a
RCR again.
a bum name to return as 0.0.0.0... we don't want ``delete xxx''
to delete the default route when xxx doesn't resolve.
Support IP number specifications as the host when specifying
a tcp-style device (rather than *just* hostnames).
is complete before checking carrier. If it's there,
the device supports carrier. If it's not it doesn't.
Add the ``set cd'' command for deciding how soon to check
for carrier, and for deciding if carrier is REQUIRED.
The default has changed: Pre 2.0 versions of ppp waited
for 1 second. Version 2 didn't wait, but this causes
problems with some (few?) modems that don't assert carrier
immediately on reporting CONNECT. The one second delay
is back now and can be removed with ``set cd 0''.
Bump the ppp version number in case this needs to be changed
again....
each time rather than making up a new one.
Increase the authname/authkey max sizes to 100 characters.
Allow ``authkey'' specifications beginning with ``!''.
When a challenge is received, the text following the
``!'' is executed as a program (expanding stuff in the same
way that ``sh'' and ``!bg'' do). The program is passed the
peer name, peer challenge and local ``authname'' on standard
input and is expected to output the name/key combination that
should be used to build the CHAP response.
This provides support for Secure ID cards (guess what I was
given at work recently!) using CHAP.
Examples will follow.
