laforge has submitted this change. ( https://gerrit.osmocom.org/c/osmo-pcu/+/33756 )
Change subject: pcu_l1_if: Document tx_pch empty IMSI scenario ......................................................................
pcu_l1_if: Document tx_pch empty IMSI scenario
Related: OS#6097 Change-Id: I327ca0e0f53be2d9b2a0705fe4de600229bdc5f9 --- M src/pcu_l1_if.cpp 1 file changed, 24 insertions(+), 0 deletions(-)
Approvals: Jenkins Builder: Verified fixeria: Looks good to me, approved laforge: Looks good to me, approved
diff --git a/src/pcu_l1_if.cpp b/src/pcu_l1_if.cpp index a256962..f42a3d4 100644 --- a/src/pcu_l1_if.cpp +++ b/src/pcu_l1_if.cpp @@ -275,6 +275,16 @@ else memset(data, '0', IMSI_DIGITS_FOR_PAGING);
+ /* OS#6097: if strlen(imsi) == 0: We assume the MS is in non-DRX + * mode (TS 44.060 5.5.1.5) and hence it is listening on all CCCH blocks + * (TS 45.002 6.5.3, 6.5.6). + * Hence, pgroup 000 is taken "randomly" to send it over it. This of + * course not optimal since it can actually be sent on any CCCH blocks, + * so we are delaying the ImmAss for no good reason. But anyway, + * pcu_l1if_tx_pch() is deprecated and pcu_l1if_tx_pch_dt() should be + * used instead, which doesn't suffer from this problem. + */ + /* block provided by upper layer comes without first byte (plen), prepend it manually: */ OSMO_ASSERT(sizeof(data) >= IMSI_DIGITS_FOR_PAGING + 1 + block->data_len); data[IMSI_DIGITS_FOR_PAGING] = (plen << 2) | 0x01; @@ -297,6 +307,10 @@ pch_dt.tlli = tlli; if (imsi) OSMO_STRLCPY_ARRAY(pch_dt.imsi, imsi); + /* OS#6097: if strlen(pch_dt.imsi) == 0: We assume the MS is in non-DRX + * mode (TS 44.060 5.5.1.5) and hence it is listening on all CCCH blocks + * (TS 45.002 6.5.3, 6.5.6). + */
pch_dt.data[0] = (plen << 2) | 0x01; bitvec_pack(block, pch_dt.data + 1);
-
laforge