In c09f8a3b7f as part of a cleanup
I accidently changed the talloc context from "con" to "bsc". The
issue occurred at an earlier commit when assigning req.ctx to the
"wrong" context. The allocation needs to be scoped by the struct
nat_sccp_connection and not the connection from BSC to NAT.
Before we have a nat_sccp_connection we scope the copied imsi to
the bsc_connection and then steal it, but for the identity resp
we will always have a nat_sccp_connection and can already use the
right context.
Change-Id: I53789aad2809e19338ad3b2deb72c4757e7bd524
Related: OS#1733
Reviewed-on: https://gerrit.osmocom.org/102
Tested-by: Jenkins Builder
Reviewed-by: Harald Welte <laforge@gnumonks.org>
Reviewed-by: daniel <dwillmann@sysmocom.de>
Reviewed-by: Holger Freyther <holger@freyther.de>
Add vty tests for BSC configuration reloading.
Load BSCs configuration on bscs-config-file command:
* remove all runtime configured BSC not in the config file
* close connections to all BSC with updated token value
Fixes: OS#1670
Sponsored-by: On-Waves ehf
Introduce new configuration option bscs-config-file which includes BSC
configuration from the given file. Both absolute and relative (to the
main config file) paths are supported.
Add 'show bscs-config' command to display current BSC configuration.
Note: it is still possible to have BSC configuration in the main
file (provided proper index number is used) and in runtime but BSC
configuration is no longer saved automatically. The management of
included configuration file is left to external tools.
Update configuration examples.
Fixes: OS#1669
Sponsored-by: On-Waves ehf
libosmocore recently added inline functions to relieve callers from applying
bitmasks and bit shifts to access the transaction id of a GSM 04.08 header.
Apply these functions.
Replace hardcoded protocol discriminator and message type bitmasks with
function calls recently introduced in libosmocore.
Note that the release 98 bitmasks slightly differ from the release 99 bitmasks.
This patch uses the "default" gsm48_hdr_msg_type invocation, thus it depends on
libosmocore whether 98 or 99 bitmasks are used.
In some places, use of the bitmask was erratic. Fix these implicitly by
employing the bitmask functions:
* silent_call.c: silent_call_reroute(): add missing bitmask for MM.
* bsc_msg_filter.c: bsc_msg_filter_initial(): RR vs. MM messages.
* osmo_bsc_filter.c: bsc_find_msc() and bsc_scan_bts_msg(): RR vs. MM
messages.
* bsc_nat_rewrite.c: bsc_nat_rewrite_msg(): SMS vs. CC messages.
* bsc_ussd.c: no bitmask is applicable for the message types used here.
* gb_proxy.c: gbproxy_imsi_acquisition(): missing bit mask for pdisc.
In gprs_gb_parse.c: gprs_gb_parse_dtap(), add a log notice for unexpected
message types.
Add ctrl_vty_init() calls and feed the ctrl_vty_get_bind_addr() return value to
ctrl_interface_setup() in the following programs:
osmo-bsc
osmo-bsc_nat
osmo-nitb
osmo-sgsn
For osmo-sgsn, move the control interface setup invocation below the config
parsing, so that the ctrl_vty_get_bind_addr() can return the configured
address.
Following the 'line vty'/'bind A.B.C.D' command added in libosmocore, use the
configured address to set the telnet bind for the VTY line. It is now possible
to publish the VTY on a specific local interface (including 0.0.0.0 aka "any").
Implement in all of:
osmo-gbproxy
osmo-gtphub
osmo-sgsn
osmo-bsc
osmo-bsc_nat
osmo-bsc_mgcp
osmo-nitb
In some of these main programs, move the telnet initialization below the
configuration parsing.
Historically, this was not a good idea for programs using bsc_init.c (aka
bsc_bootstrap_network()), since they expected a gsm_network struct pointer in
((struct telnet_connection*)vty->priv)->priv, so that telnet had to be either
initialized or replaced by a dummy struct. In the meantime, the gsm_network
struct is not actually looked up in a priv pointer but in the static bsc_vty.c
scope (bsc_gsmnet), so this limitation is mere legacy (even though said legacy
is still there in an "#if 0" chunk).
In the other binaries I have briefly looked at the init sequence dependencies
and found no reason to initialize telnet above the config file parsing. In any
case, I have tested every single one of abovementioned binaries to verify that
they still parse the example config successfully and launch, allowing VTY
connections on the configured address(es). I hope this suffices.
In all of the above, log VTY address and port. LOGL_INFO is disabled by default
in some of the logging scopes, and since it is a single log message right at
program launch, I decided for the slightly more aggressive LOGL_NOTICE.
Remove unused talloc.h from bsc_vty.c.
In bsc_nat.c, use OSMO_CTRL_PORT_BSC_NAT instead of hardcoding port number, and
include ctrl/ports.h for that.
Fix comment typo "COMAMND"
Add new kitchen sink openbsc/utils.h and libcommon/utils.c to make three so far
static functions public (so I can use them in the upcoming OAP code).
A place to put them could have been the gprs_utils.h, but all general functions
in there have a gprs_ prefix, and todo markings to move them away. All other
libcommon headers are too specific, so I opened up this kitchen sink header.
Replace the implementation of encode_big_endian() with a call to
osmo_store64be_ext(). See comments.
Apply the change in Makefiles and C files.
We put a signed integer into this string but did not account
for the newline and for the terminating NUL of the string. Add
the newline to the string and add one for NUL. Spotted while
accidently having a CID of 255.
There appears to be a leak of CIDs:
<000b> mgcp_osmux.c:544 All Osmux circuits are in use!
There are paths that a CID had been requested and never released
of the NAT. Remember the allocated CID inside the endpoint so it
can always be released. It is using a new variable as the behavior
for the NAT and MGCP MGW is different.
The allocated_cid must be signed so that we can assign outside
of the 0-255 range of it.
Fixes: OW#1493
Extend the osmux only setting from the MGCP MGW to the NAT. This
is applied when an endpoint is allocated and/or when the allocation
is confirmed by the remote system.
Not tested. The impact should only be when the new option is
being used.
Fixes: OW#1492
Make it possible to bind the call-agent to a specific IP address
and the network and bts end to different ip addresses. Begin by
clarifying which source ip address we want to have.
The parsing code assumed that there will be a single payload
type and this assumption is clearly wrong. Forward all of the
payload types. The code is still only extracting the first
type from the list. The variable name has been renamed to
reflect this.
vty_interface_layer3.c:584:4: warning: format '%d' expects argument of type 'int', but argument 3 has type 'long unsigned int' [-Wformat=]
sizeof(subscr->extension)-1, VTY_NEWLINE);
We don't need to consume all the entropy of the kernel but can
use libcrypto (OpenSSL) to generate random data. It is not clear
if we need to call RAND_load_file but I think we can assume that
our Unices have a /dev/urandom.
This takes less CPU time, provides good enough entropy (in theory)
and leaves some in the kernel entropy pool.
We are using the token to find the right bsc_config and
then we can use the last_rand of the bsc_connection to
calculate the expected result and try to compare it with
a time constant(???) memcmp.
Check if the NAT has sent 16 bytes of RAND and if a key
has been configured in the system and then generate a
result using milenage. The milenage res will be sent and
noth the four byte GSM SRES derivation.
Generate 16 byte of random data to be used for A3A8 by
the BSC in the response. We can't know which BSC it is
at this point and I don't want to send another message
once the token has been received so always send the data
with an undefined code. The old BSCs don't parse the
message and will happily ignore the RAND.
/dev/urandom can give short reads on Linux so loop
around it until the bytes have been read from the kernel.
Instead of doing open/read/close all the time, open the
FD in the beginning and keep it open. To scare me even
more I have seen /dev/urandom actually providing a short
read and then blocking but it seems to be the best way
to get the random byes we need for authentication.
So one should/could run the cheap random generator on
the system (e.g. haveged) or deal with the NAT process
to block.
Unfortunately the basic structure of the response is broken.
There is a two byte length followed by data. The concept of
a 'tag' happens to be the first byte of the data.
This means we want to write strlen of the token, then we
want to write the NUL and then we need to account for the
tag in front.
Introduce a flag if the new or old format should be used.
This will allow to have new BSCs talk to old NATs without
an additional change. In the long run we can clean that up.
In case the token was not correct, just close the connection.
It is not clear that forcing a new TCP connection is going to
give us any extra security here. But with the upcoming auth
handling it does make sense to have both case look similar.
For the BSC we will have the gsm48_hdr and don't need to
find data within SCCP. For legacy reasons we need to
initialize con_type, imsi, reject causes early on and
need to do the same in the filter method.
This means we need to require a talloc context and
simply operate on the list. I had considered creating
a structure to hold the list head but I didn't find
any other members so omitted it for now.
Move the filter methods to the filter module. This is
still only usable for the NAT and the _dt/_cr filter
routines need to move back to the bsc_nat in the long
run.
For customer requirements we want to be able to do
filtering on the BSC as well. The same messages need
to be scanned and the same access-lists will be looked
at. In the future we might even split traffic based
on the IMSI. Begin with moving the code to a new top
level directory and then renaming and removing the
nat dependency.
Currently the handling of the buffers is not done consistently. Some
code assumes that the whole buffer may be used to store the string
while at other places, the last buffer byte is left untouched in the
assumption that it contains a terminating NUL-character. The latter
is the correct behaviour.
This commit changes to code to not touch the last byte in the buffers
and to rely on the last byte being NUL. So the maximum IMSI/IMEI
length is GSM_IMSI_LENGTH-1/GSM_IMEI_LENGTH-1.
For information: We assume that we allocate the structure with
talloc_zero. This means we have NULed the entire imsi array and then
only write sizeof - 1 characters to it. So the last byte remains NUL.
Fixes: Coverity CID 1206568, 1206567
Sponsored-by: On-Waves ehf
Currently the inner loop in show_bsc_mgcp iterates of the timeslot
interval [0, 31]. Timeslot 0 is not valid, which causes
mgcp_timeslot_to_endpoint to generate a corresponding warning and to
return an invalid endp value. That value causes an out-of-bound
read access, possibly hitting unallocated memory.
This patch fixes the loop range by starting with timeslot 1.
Note that this does not prevent mgcp_timeslot_to_endpoint from
returning an invalid endpoint index when called with arguments not
within its domain.
Addresses:
<000b> ../../include/openbsc/mgcp.h:250 Timeslot should not be 0
[...]
vty=0xb4203db0, argc=1, argv=0xbfffebb0) at bsc_nat_vty.c:256
max = 1
con = 0xb4a004f0
i = 0
j = 0
[...]
==15700== ERROR: AddressSanitizer: heap-use-after-free on address
0xb520be4f at pc 0x8062a42 bp 0xbfffeb18 sp 0xbfffeb0c
Sponsored-by: On-Waves ehf
Holger Hans Peter Freyther
Harald Welte
Neels Hofmeyr