This patch refactors SGSN NSEI handling to support a secondary SGSN.
It adds the following VTY commands:
- secondary-sgsn nsei <0-65534>
- no secondary-sgsn
Sending messages to the secondary SGSN is not yet implemented, but
received messages from such a SGSN would be forwarded to the BSS
peers.
Sponsored-by: On-Waves ehf
To modify or route messages based on the IMSI the latter must be known
when the action shall take place.
This patch modifies the gbproxy to optionally retain and enqueue
messages from the MS while initiating an identification procedure.
Further message processing of the LLC PTP link towards the SGSN will
be done, when the identity of the MS has been acquired.
Note that the N(U) of the LLC GMM SAPI are not adjusted, so it is
possible that adjacent messages of a single LLC link arriving either
at the BSS or the SGSN have the same N(U) and might get discarded,
leading to retransmissions and additional delay.
Note also that retransmissions and packet loss are not yet handled
explicitely. If for instance the generated IDENT REQ gets lost, the
gbproxy will not act on its own. In this case, the MS will time out
and eventually resend the Attach Request on which the gbproxy will
act exactly like before (thus having two Attach Req messages in its
queue, which will both be sent after the Ident Resp arrives).
This has been tested successfully with an E71, needing one
retransmission by the SGSN due to an N(U) collision.
Ticket: OW#1261
Sponsored-by: On-Waves ehf
This patch moves the peer related definitions from gb_proxy.c to
gb_proxy_peer.c and adjusts the prefix of each global symbol to
gbproxy_:
Peer definitions (prefix adjusted to gbproxy_):
peer_ctr_description -> gprs/gb_proxy_peer.c (static)
peer_ctrg_desc -> gprs/gb_proxy_peer.c (static)
*peer_by_* -> gprs/gb_proxy_peer.c
gbproxy_peer_alloc -> gprs/gb_proxy_peer.c
gbproxy_peer_free -> gprs/gb_proxy_peer.c
gbprox_cleanup_peers -> gprs/gb_proxy_peer.c
Sponsored-by: On-Waves ehf
This patch moves several functions and declarations out of gb_proxy.c
to make them reusable by other components and to separate them by
context and task.
Counter enums (prefix is changed to gbproxy_):
enum gbprox_global_ctr -> gprs/gb_proxy.h
enum gbprox_peer_ctr -> gprs/gb_proxy.h
Generic Gb parsing (prefix is changed to gprs_gb_):
struct gbproxy_parse_context -> openbsc/gprs_gb_parse.h
gbprox_parse_dtap() -> gprs/gprs_gb_parse.c
gbprox_parse_llc() -> gprs/gprs_gb_parse.c
gbprox_parse_bssgp() -> gprs/gprs_gb_parse.c
gbprox_log_parse_context() -> gprs/gprs_gb_parse.c
*_shift(), *_match() -> gprs/gprs_gb_parse.c (no prefix)
gbprox_parse_gmm_* -> gprs/gprs_gb_parse.c (static)
gbprox_parse_gsm_* -> gprs/gprs_gb_parse.c (static)
MI testing/parsing (prefix gprs_ added):
is_mi_tmsi() -> gprs/gprs_utils.c
is_mi_imsi() -> gprs/gprs_utils.c
parse_mi_tmsi() -> gprs/gprs_utils.c
TLLI state handling (prefix is changed to gbproxy_):
gbprox_*tlli* -> gprs/gb_proxy_tlli.c
(except gbprox_patch_tlli, gbproxy_make_sgsn_tlli)
Message patching (prefix is changed to gbproxy_):
gbprox_*patch* -> gprs/gb_proxy_patch.c
gbprox_check_imsi -> gprs/gb_proxy_patch.c
Sponsored-by: On-Waves ehf
This VTY command add the following commands to the gbproxy node:
- patch-ptmsi: Enables P-TMSI/TLLI patching
- no patch-ptmsi: Disables P-TMSI/TLLI patching
Note that using these commands interactively can load to undefined
behavior of existing LLC connections.
Sponsored-by: On-Waves ehf
This patch separates BSS side from SGSN side TLLI/PTMSI tracking. When
TLLI/PTMSI patching is not enabled, the corresponding states shall be
identical. The TLLI/PTMSI state has been moved into the struct
gbproxy_tlli_state and is used twice in gbproxy_tlli_info.
Since the state handling for uplink and downlink messages is
diverging, gbprox_update_state() is replaced by two functions
gbprox_update_state_dl/gbprox_update_state_ul and
gbprox_process_bssgp_message() is replaced by
gbprox_process_bssgp_dl/gbprox_process_bssgp_ul.
Sponsored-by: On-Waves ehf
Add a separate function to clear the IMSI filter to be used instead of
gbprox_set_patch_filter(cfg, NULL, ...). Albeit it fixes a Coverity
issue (Unchecked return value), it is a false positive, since the
return value is always 0 in these cases. Nevertheless it is more
obvious what happens when an explicit clear function is called. Using
NULL as filter argument of gbprox_set_patch_filter still clears the
filter.
Fixes: Coverity CID 1231255
Sponsored-by: On-Waves ehf
Currently only TLLIs for which it is known that they may be patched
are put into the TLLI list.
This patch changes this to add TLLIs even when the IMSI is not yet
known. A enable_patching flag is added to the gbproxy_tlli_info
structure to control patching.
Note that this puts every active TLLI into the list where accesses
are O(N) currently.
Sponsored-by: On-Waves ehf
Global state prevents us from writing simple units tests for
single routines. Go through the code and add pointers to the
gbproxy configuration. Only the vty and the test code remain
using the global gbproxy instance.
Create a testcase for the gprs_str_to_apn and gprs_apn_to_str
routines. While writing the testcase we noticed it is possible to
write more bytes than should have been allowed. This is fixed by
checking that the max_len is at least 1 (needed to write the first
length octet) and to do the size check before writing to the output.
Modify the signature of gprs_str_to_apn to put the length/size next
to the parameter that requires a size.
Done with Jacob
We intend to move some of these routines to libosmocore but to avoid
a feature symbol clash we are prefixing these routines with gprs_.
Done with Jacob
The application is called gbproxy but the structures and functions
were inconsistently named as either gbprox or gbproxy. Rename all
structures to use gbproxy.
Done with Jacob
Move the global data into the struct and use it. gbprox_reset will
first free data and then re-initialize the structure. This code is
used by the unit test.
Done with Jacob
These commands manage the TLLI list used to decide whether an APN
shall be patched or not. Note that this list is (currently) only
maintained if IMSI matching is used.
VTY commands (enable node):
show gbproxy tllis show all TLLI entries
delete-gbproxy-tlli NSEI stale purge all stale entries
delete-gbproxy-tlli NSEI imsi IMSI purge entry with the IMSI given
delete-gbproxy-tlli NSEI tlli TLLI purge entry with the TLLI given
Sponsored-by: On-Waves ehf
This patch adds IMSI/TLLI connection tracking and uses it to control
APN patching based on the IMSI. TLLI entries can expire based on age
and/or by limiting the TLLI list size.
VTY config-gbproxy:
no core-access-point-name disable APN patching
core-access-point-name none remove APN if present
core-access-point-name APN replace APN if present
core-access-point-name none match-imsi RE remove if IMSI matches
core-access-point-name APN match-imsi RE replace if IMSI matches
tlli-list max-age SECONDS expire after SECONDS
no tlli-list max-age don't expire by age
tlli-list max-length N keep N entries only
no tlli-list max-length don't limit list length
RE is an extended regular expression, e.g. ^12345|^23456
Ticket: OW#1192
Sponsored-by: On-Waves ehf
Patch the APN in every 'Activate PDP Context Request' message to the
value given by the 'core-access-point-name' command. If the command is
given without an APN, the whole APN IE will be removed. If the
command is being prefixed by a 'no', the APN IE remains unmodified.
The patch mode 'llc-gsm' is added to selectively enable the patching
of LLC session management messages. This is enabled implicitely by
the patch mode 'llc'.
Note that the patch mode should not be set to a value not enabling
the patching of LLC GSM messages ('llc-gsm', 'llc', and 'default' are
sufficient to patch 'Activate PDP Context Request' messages).
Ticket: OW#1192
Sponsored-by: On-Waves ehf
This patch extends the BSSGP patch code to also patch LLC information
elements along with MCC/MNC patching support for the following messages:
- Attach Request
- Attach Accept
- Routing Area Update Request
- Routing Area Update Accept
- P-TMSI reallocation command
Note that encrypted packets will not be patched.
Ticket: OW#1185
Sponsored-by: On-Waves ehf
This adds a feature to patch the BSSGP MNC/MCC fields of messages going
to and coming from the SGSN. To enable this feature, the gbproxy's
VTY commands 'core-mobile-country-code' and/or
'core-mobile-network-code' must be used. All packets to the SGSN are
patched to match the configured values. Packets received from the
SGSN are patched to the corresponding values as last seen from the BSS
side.
Note that this will probably not work with a gbproxy used for several
BSS simultaneously.
Note also, that MCC/MNC contained in a LLC IE will not be patched.
Ticket: OW#1185
Sponsored-by: On-Waves ehf
Remove ournode_exit_cmd, ournode_end_cmd, and bsc_install_default()
since this functionality is provided by the current libosmocore.
Replace calls to bsc_install_default() by call to
vty_install_default() with the following semantic patch:
@rule1@
expression N;
@@
- bsc_install_default(N);
+ vty_install_default(N);
Ticket: OW#952
Sponsored-by: On-Waves ehf
This adds the option to delete all BVC peers and/or NS_VC with a
given NSEI with a single command. Static (configured) NS-VC are not
affected. In addition, all connections for this NSEI that can be
deleted by this command can be listed without deleting them by
appending 'dry-run' to the command.
Sponsored-by: On-Waves ehf
Add bsc_install_default() and replace all install_default()
This patch adds bsc_install_default() which calls install_default()
and add 'exit' and 'end'. All other calls to install_default() are
replaced by calls to bsc_install_default().
Since 'exit' and 'end' are now added automatically to each node, the
explicit registrations of these commands are removed by this patch,
too.
The related tests succeed now without work-arounds (except for the
'config' node itself which is part of libosmocore).
Some nodes below 'config' didn't have ournode_exit / ournode_end,
and thus were not able to properly perform this function. exit should
always only go back one level, while end drops us back to ENABLE_NODE.
The prompt now represents the nesting level, and there's one consistent
space after the final prompt character (typically #).
libosmogsm is a new library that is distributed in the libosmocore.
Now, openbsc depends on it. This patch gets openbsc with this
change.
This patch also rewrites all include path to the new
osmocom/[gsm|core]
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
The reason for this is quite simple: We want to make sure anyone
running a customized version of OpenBSC to operate a network will
have to release all custom modifiations to the source code.
Almost all parameters about the SGSNs NS-VC can be specified in the NS
protocol node. All that needs to remain in the gbproxy config node
is "nsip sgsn nsei XXX".
We want the VTY and telnet code to be independent from the BSC
application(s). As a side note, we also like to eliminate static
global variables for 'struct gsm_network' all over the code.
As such, telnet_init() is now passed along a "private" pointer,
which getst stored in telnet_connection.priv. This telnet_connection
is then stored in vty->priv, which in turn gets dereferenced if
anyone needs a reference to 'struct gsm_network' from the BSC vty
code.
Also:
* vty_init() now calls cmd_init()
* the ugliness that telnet_init() calls back into the application by means of
bsc_vty_init() function has been removed.
* telnet_init() now returns any errors, so the main program can exit
e.g. if the port is already in use.
Using "end" you can always return to the "enable" level, and from
there the "show" commands are available. So no more need for
exit/exit/exit/exit/disable.
With persistent NS-VC configuration (configured through VTY),
we can respond properly to BSS with a somewhat strange NS
implementation Such as the BSplus. It enables us to respond
with a proper NS-RESET (including NSVCI/NSEI) when receiving
a NS-ALIVE or other PDU for a BLOCKED/DEAD NS-VC after our
end of the connection is rebooted.