The core functionality of input/lapd.c is removed. Now it uses lapd_core.c
of libosmogsm. The stucture of lapd_instance and SAP (SAPI/TEI handling)
is kept, as well as interfaceing and header transcoding. The former
implementation of datalink is completely replaced, except for the minimal
TEI manager..
Currently it supports 3 modes:
- ABIS (BS11/Ericsson/Nokia)
- ISDN (Not used yet)
- ASAT (A interface for satellite)
all these modes can run as NETWORK or USER.
the "e1_line <0-255> port <0-255>" vty command allows the user to
set which physical port/card number should be represented by the
given virtual e1_line.
Furthermore, we now actually query the DAHDI hardware to determine the
number of ports of a given span (e.g. only 24 in case of T1) instead of
blindly assuming there are 31 timeslots on each port.
This specifically will fix T1 timeslot (/dev/dahdi/%u) calculation in
setups with multiple DAHDI spans/ports and a T1 span != span 1.
With multiple BTS attached to a single line, we have to call
->line_update() multiple times. I broke this myself while avoiding
that A-bis over IP drivers bind to the socket several times.
To fix this situation, Harald prefers that this case is internally
handled by the ipaccess and hsl drivers by means of the driver_data
field in the e1inp_line structure.
Reported-by: Gus Bourg <gus@bourg.net>
struct e1inp_line_ops {
- enum e1inp_line_role role;
- char *addr;
- void *data;
+ union {
+ struct {
+ enum e1inp_line_role role; /* BSC or BTS mode. */
+ const char *addr; /* IP address .*/
+ void *dev; /* device parameters. */
+ } ipa;
+ struct {
+ const char *port; /* e.g. /dev/ttyUSB0 */
+ unsigned int delay;
+ } rs232;
+ } cfg;
Now this structure contains the configuration details for the
virtual E1 line, instead of using a pointer.
This also get the line_update callback to its original layout:
+ int (*line_update)(struct e1inp_line *line);
Scenario: BTS are configured and working, then the BSC stops working
for some reason (crash or administrative stop).
If the BSC comes back to life, LAPD among other things does not know
about the previous existing TEIs. Instead of ignoring these frames,
we notify the driver that we are seeing frames with unknown TEIs, so
it can try to recover, e.g. by resending the SABM message.
It's not a good idea to confuse the two changes with each other. Moving the
Abis part into a separate library is independent from the question whether we
have talloc inside libosmocore or use a stand-alone talloc library.
This patch 's/e1inp_line_get/e1inp_line_find/g' since we need this
function name for the new refcounting scheme.
Basically, I have added a new function to clone lines that is used
by the ipaccess driver:
struct e1inp_line *e1inp_line_clone(void *ctx, struct e1inp_line *line);
And two functions to bump and decrement the refcount:
void e1inp_line_get(struct e1inp_line *line);
void e1inp_line_put(struct e1inp_line *line);
This is useful to avoid leaking virtual E1 lines in the ipaccess
case, since we have two sockets for OML and RSL respectively, we
have to release the line *once* both sockets have been closed.
Without this patch, there are cases in which we don't know if it's
time to release the virtual E1 line.
This patch also includes a fix to avoid crashing if we open a
connection with OML/RSL port without sending any ID_RESP message
(in that case, we have no chance to set the signal link). I tested
these situations with netcat.
This patch is a major update of the callback infrastructure, now
the e1input_ops looks like the following:
struct e1inp_sign_link * (*sign_link_up)(void *unit_info, struct e1inp_line *line, enum e1inp_sign_type type);
void (*sign_link_down)(struct e1inp_line *line);
int (*sign_link)(struct msgb *msg, struct e1inp_sign_link *link);
The sign_link_up and sign_link_down will be used by the A-bis over IP
input drivers.
The sign_link_up callback is used if we receive a ID_RESP message, in
that case, we have to set up the sign link for the corresponding new
OML/RSL signal link. The pointer to unit_info provides a data structure
that contains the BTS device details if we run as BSC, and the requested
device information from the BSC if we run as BTS. The sign_link_up
callback must return the new sign_link created.
The sign_link_down callback is invoked if the line does down, which
means that the counterpart has closed the socket.
The sign_link callback is used to handle all RSL/OML messages.
I have also added the following callback to the e1inp_driver:
+ void (*close)(struct e1inp_ts *ts);
Which is invoked if you call e1inp_sign_link_destroy(). This callback
is used to close the socket that is linked to that timeslot. This is
useful for A-bis over IP drivers since sockets are closed if the
OML/RSL signalling link is destroyed.
As you can notice, I have also added all the ID_RESP parsing into
libosmo-abis for both ipaccess and hsl drivers.
This patch also contains a rework of the ipa_client_link whose
integration with the e1_input infrastructure was broken (the
transmission path was broken).
This patch also contains more develop examples that act as BSC
and BTS for the ipaccess driver.
Sorry, I know it would be better to split all these changes into
logical pieces but many of them are tightly related.
This is under heavy development stage, it's anyway hard to track
changes until this becomes more stable.
This patch adds generic abis_sendmsg to send NM messages (both OML and RSL).
abis_rsl_sendmsg(...) is basically the same, we'll remove it from
libosmo-abis once we can propagate changes to openbsc.
This patch uses the new libosmocore logging infrastructure
that allows to invoke log_init(&my_log_info) multiple times
so we can register categories from libraries and applications.
struct e1inp_line_ops {
int (*sign_link_up)(struct msgb *msg, struct e1inp_line *line);
int (*sign_link)(struct msgb *msg, struct e1inp_sign_link *link);
int (*error)(struct msgb *msg, int error);
};
The description of the operations is the following:
* sign_link_up is invoked if the signalling link becomes up. In A-bis
over IP, we have to wait until the other peer identifies itself as
a BTS/BSC device, then this function is invoked. This function is not
used by ISDN drivers, the signalling link can be set up just after
the line is created.
* sign_link is called if we receive OML/RSL message. This function
is used both by ISDN and A-bis over IP drivers.
* error is called if we receive a malformed message. It is used both
by ISDN and A-bis over IP drivers.
With this patch, we pass TRAU frames to the callback that
e1inp_ts_config_trau(...) takes as parameter. Instead of passing
it to the line->rx(...) callback. The function
e1inp_ts_config_trau(...) should only be used by ISDN drivers.
Andreas Eversberg
Harald Welte