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
PPPoUDP connection.
(*) This is as correct as ftp and uucp wtmp entries are - that is,
multiple concurrent connections will not record enough information
in wtmp to tell last(1) who was logged in for how long.
0.81.1 of the i4b code - namely support of the I4B_VR_REQ
ioctl via the i4brbchX device.
Ppp controls the phone number, but idle timers and
SYNC/RAW decisions are still made by isdnd (in isdnd.rc).
This involves a new datalink state machine phase. The
``wait for carrier'' phase happens after dialing but
before logging in. The whole dial state should really
be abstracted so that each device type can deal with it
in its own way (thinking about PPPoE) - but that'll have
to wait.
The ``set cd'' symantics remain the same for tty devices,
but we now delay until we either get CD or timeout waiting
(at which time we drop the link if we require CD).
For i4b devices we always insist on carrier.
Thanks to hm@ for his help, and especially for pointing out
that I *don't* need to re-implement isdnd (that was a huge
waste of time !) :-]
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''.
device per argument rather than the old way of concatenating
everything then splitting the result at commas and whitespace.
Old syntax of ``set device /dev/cuaa0, /dev/cuaa1''
may no longer contain the comma, but syntax such as
``set device "!ssh host ppp -direct label"'' is now
possible.
with more than one read(). When we detect one, don't
forget to pass it to async_Input() and drop our
terminal back into command mode.
Don't output an extraneous \r if we're passed \r\n
to prompt_vprintf in raw mode.
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....
the answer.
If we later get a descriptor exception from select(), we know
that it's a tty (isatty() returns 0 after the exception on a
tty) and remember to call modem_LogicalClose().
The upshot of it all is that descriptor exceptions dont leave
the tty locked any more.
anything for two mintues (see ``set choked'' and ``show
bundle''), nuke the ip, mp and link level buffer queues.
This should fix problems where ``ppp -auto'' seems to stop
responding after failing to connect to the peer a few times.
that we're now closing, manually HUP that session leader
so that the tty is fully released.
o Always restart our carrier detect timer in the receiving
process if it was running in the sending process (as we
now *always* pass the descriptor).
o Tweak argv when we go into pause() mode to keep our session
so that ps can see what's going on (without checking for a
`pause' state in `ps -l').
is not possible to switch to or from dedicated or direct mode,
but all other combinations are ok (eg. -auto -> -ddial).
o Cope with the fact that commands with optional context may not
be able to obtain a link with command_ChooseLink() (if all links
have been deleted for example).
o Allow `clone'ing in non-multilink mode. We may for example want
to configure two links in unilink mode and dial them both, using
the one that comes up first. It's also possible to rename
``deflink'' by cloning it, deleting the original, then setting
the mode of the new link.
the bundle has the opportunity to go PHASE_DEAD and cleanup
the interface (if it's the last link).
o Regnerate our phys_type value when we transfer the link.
o Always clean up the interface when destroying our bundle in case
we're abending.
o Always clean up our interface when the last link is gone rather than
delaying things 'till exit time in the -direct case (the interface
is useless anyway). Do this *after* slamming down our NCPs (if
they're still around).
o Our MP server descriptor now clears the relevent device descriptor
from our descriptor [fd]sets when a datalink is on death-row (to
be transferred to another running ppp), thus avoiding the possibility
of passing a bum descriptor to select() and having ppp abend.
o Handle the MP socket descriptor functions from within the bundle
descriptor functions. Now we ensure that the MP socket descriptor
functions see the descriptor sets *after* they've been seen by our
datalinks.
o Add/fix a few more comments.
exec()ing. Tidy up file dups in general prior to exec().
This prevents our tun device (fd 3) from staying open (and
configured) despite handing off all it's links and exiting
(because ``cat'' holds it open).
o Don't bother SIG_DFL'ing signals before exec() as they're
already trapped with specific handlers and will be handled
correctly by the exec.
o Use values from paths.h for "/dev/" and "/dev/tty".
o Don't assert() in physical.c.
expect-send-send !
o Say `disabled' rather than 0s in `show timeout'.
o Set all arguments in ``set device'' rather than just
the first (read: quotes aren't necessary).
o Set the device speed correctly (broken in last commit).
o Shuffle things that live at the datalink level into
``show link'' rather than ``show modem''.
o Make both ``show'' commands prettier and more consistent,
and display carrier status, link type and our name in
``show modem''.
o Show redial and reconnect information in ``show link''
and remove ``show redial'' and ``show reconnect''.
o Down the correct link in bundle_LinkLost().
o Remove stale -direct and -background links at the end
of our main loop, not when we know they're going. This
prevents unexpected pointer-invalidations...
o If we ``set server'' with the same values twice, notice
and don't moan about failure.
o Record dial script despite our link mode. The mode may
be changed later (next mod) :-) We never run scripts
in -direct and -dedicated modes.
o Make ``set server none'' functional again.
o Correct datalink state array so that we don't report an
``unknown'' state.
o Pass struct ipcp to IpcpCleanInterface, not struct fsm.
o Create TUN_PREFIX define rather than hard-coding in main.c
o prompt_TtyInit now handles a NULL prompt for -direct mode
rather than having to create one then destroy it uncleanly.
o Mention our mode in the "PPP Started" LogPHASE message.
o Bring all auto links up when we have something to send.
o Remove some redundant Physical_*() functions.
o Show which connection is running a command when logging
commands.
o Initialise throughput uptime correctly.
o Move Var*Version into command.c
o Remove struct pppVars (and there was much rejoicing) !
o Forward-decl some structs in .h files to avoid include
ordering requirements and remove a few more redundant
#includes.
o Remove bundle2lcp(), bundle2ccp() and bundle2link().
They're too resource-hungry and we have `owner pointers'
to do their job.
o Make our FSM understand LCPs that are always ST_OPENED
(with a minimum code that != 1).
o Send FSM code rejects for invalid codes.
o Make our bundle fsm_parent deal with multiple links.
o Make timer diagnostics pretty and allow access via ~t
in `term' mode (not just when logging debug) and
`show timers'. Only show timers every second in debug
mode, otherwise we get too many diagnostics to be useful
(we probably still do). Also, don't restrict ~m in term
mode to depend on debug logging.
o Rationalise our bundles' phases.
o Create struct mp (multilink protocol). This is both an
NCP and a type of struct link. It feeds off other NCPs
for output, passing fragmented packets into the queues
of available datalinks. It also gets PROTO_MP input,
reassembles the fragments into ppp frames, and passes
them back to the HDLC layer that the fragments were passed
from.
** It's not yet possible to enter multilink mode :-( **
o Add `set weight' (requires context) for deciding on a links
weighting in multilink mode. Weighting is simplistic (and
probably badly implemented) for now.
o Remove the function pointers in struct link. They ended up
only applying to physical links.
o Configure our tun device with an MTU equal to the MRU from
struct mp's LCP and a speed equal to the sum of our link
speeds.
o `show {lcp,ccp,proto}' and `set deflate' now have optional
context and use ChooseLink() to decide on which `struct link'
to use. This allows behaviour as before when in non-multilink
mode, and allows access to the MP logical link in multilink
mode.
o Ignore reconnect and redial values when in -direct mode and
when cleaning up. Always redial when in -ddial or -dedicated
mode (unless cleaning up).
o Tell our links to `staydown' when we close them due to a signal.
o Remove remaining `#ifdef SIGALRM's (ppp doesn't function without
alarms).
o Don't bother strdup()ing our physical link name.
o Various other cosmetic changes.
Struct bundle will have its own struct ccp in the future
too.
o The ``set stopped'' command now requires context and doesn't
work on the IPCP FSM.
o Check if it's time to break out of our top level loop before
doing a select - otherwise, we'll select forever :-(
o Remove `struct link'::ccp (a temporary hack). It turns out
that IpStartOutput() calls link_Output() and link_Output()
incorrectly calls StartOutput() (really modem_StartOutput)
requiring the ccp knowledge so that it can call
IpStartOutput()... The end result is that the whole IP
output queue gets dumped into the modem output queue
and a pile of physical writes are done prematurely. This
makes the (original) code in main() actually work in that
it would not bother selecting() on the tun descriptor when
our modem queue length was 20 or greater. Instead, we now
make that decision based on the overall queue length.
This will need improvement later.
o Move our LCP report timer into struct hdlc - it's really
a hdlc timer (fcs errors etc).
o Make `show hdlc' require context and make the output more
friendly.
o Remove all non-const globals from hdlc.c
o Output peer-rejected protocols by name - not just ones
that we reject.
Allow for NULL fd_sets in descriptor_UpdateSet()
Reimplement the entire chat module, creating
`struct chat' - a `type' of struct descriptor.
Remove CARRIER logging.
CONNECT logging now only logs "CONNECT" lines. CHAT logging
masks it with an entire log of the conversation.
Modem dialing is now asynchronous, including pauses
and timeouts :-)
The hooks in DoLoop() in main.c are *very* messy ! I'll have
to rewrite DoLoop fairly soon, so I don't care too much for the
moment. This code is pretty raw.
This will ultimately be a member of a list of descriptors and
their handler functions on which we need to select() in the
main loop.
o Make struct physical into a `sort' of struct descriptor.
This structure contains the asynchronous state of the physical
link.
Unfortunately, just about every .h file is included in every .c
file now. Fixing this can be one of the last jobs.
