cellular-infrastructure
/
osmo-msc
mirror of https://gerrit.osmocom.org/osmo-msc
9
0
Fork 0
Code Issues Releases Wiki Activity

VLR: reject overlong IMSIs in ID RESP messages 

Overlong IMSIs in ID RESP messages were accepted and used in
truncated form.

Log an error when truncation occurs, and prevent truncated IMSIs
from being installed for a subscriber via ID RESP messages.
Other code paths leading to vlr_subscr_set_imsi() with truncated
IMSIs will only a leave a trail of log entries for now, because
vlr_subscr_set_imsi() is currently unable to return an error code.

Change-Id: I785c994f41a646d8d83d3d82f5a9ae6b572eb641
Related: OS#2864
This commit is contained in:
Stefan Sperling 2018-06-25 17:31:59 +02:00 committed by Harald Welte
parent caf2fe5269
commit 9fbb6008e0
1 changed files with 13 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
src/libvlr/vlr.c
View File

@ -396,7 +396,13 @@ void vlr_subscr_set_imsi(struct vlr_subscr *vsub, const char *imsi)
{
if (!vsub)
return;
OSMO_STRLCPY_ARRAY(vsub->imsi, imsi);
if (OSMO_STRLCPY_ARRAY(vsub->imsi, imsi) >= sizeof(vsub->imsi)) {
LOGP(DVLR, LOGL_NOTICE, "IMSI was truncated: full IMSI=%s, truncated IMSI=%s\n",
imsi, vsub->imsi);
/* XXX Set truncated IMSI anyway, we currently cannot return an error from here. */
}
vsub->id = atoll(vsub->imsi);
DEBUGP(DVLR, "set IMSI on subscriber; IMSI=%s id=%llu\n",
vsub->imsi, vsub->id);
@ -1062,10 +1068,15 @@ int vlr_subscr_rx_id_resp(struct vlr_subscr *vsub,
/* update the vlr_subscr with the given identity */
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
if (vsub->imsi[0]
if (strlen(mi_string) >= sizeof(vsub->imsi)) {
LOGVSUBP(LOGL_ERROR, vsub, "IMSI in ID RESP too long (>%zu bytes): %s\n",
sizeof(vsub->imsi) - 1, mi_string);
return -ENOSPC; /* ignore message; do not avance LU FSM */
} else if (vsub->imsi[0]
&& !vlr_subscr_matches_imsi(vsub, mi_string)) {
LOGVSUBP(LOGL_ERROR, vsub, "IMSI in ID RESP differs:"
" %s\n", mi_string);
/* XXX Should we return an error, e.g. -EINVAL ? */
} else
vlr_subscr_set_imsi(vsub, mi_string);
break;