diff options
| author | Sylvain Munaut <tnt@246tNt.com> | 2019-03-14 11:02:36 +0100 |
|---|---|---|
| committer | Harald Welte <laforge@gnumonks.org> | 2019-03-19 15:24:01 +0000 |
| commit | da9f37ed201be1fc12f6bbf8621fe489056d9012 (patch) | |
| tree | b205ef5712583a53ddcded15bf153ac0082680c7 /src/libvlr/vlr_lu_fsm.c | |
| parent | 31f4c1f927352a5e50348b80bb61f3c8b4cdc799 (diff) | |
libvlr: Allow 2G auth tuples to be re-used without going through AUTH
If the key_seq we get in the first messages matches the last_tuple, then
both we and the MS already know the key to use and we don't need the
AUTH REQUEST/RESPONSE cycle.
Security wise ... not so good, and so IMHO the 'auth required' option
in the MSC should always be set. But this allows to turn on ciphering on
a channel without doing any MM transaction, and so the MS doesn't turn
on the T3240 timer which allows to have a ciphered silent-call channel
that won't timeout.
Change-Id: Ief840a2ae7a0ffd2bf0bf726f209a79e3f787646
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Diffstat (limited to 'src/libvlr/vlr_lu_fsm.c')
| -rw-r--r-- | src/libvlr/vlr_lu_fsm.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/src/libvlr/vlr_lu_fsm.c b/src/libvlr/vlr_lu_fsm.c index 8152d20e8..7ddf4558d 100644 --- a/src/libvlr/vlr_lu_fsm.c +++ b/src/libvlr/vlr_lu_fsm.c @@ -685,6 +685,7 @@ struct lu_fsm_priv { struct osmo_location_area_id new_lai; bool authentication_required; bool ciphering_required; + uint8_t key_seq; bool is_r99; bool is_utran; bool assign_tmsi; @@ -705,7 +706,8 @@ static bool is_auth_required(struct lu_fsm_priv *lfp) /* The cases where the authentication procedure should be used * are defined in 3GPP TS 33.102 */ /* For now we use a default value passed in to vlr_lu_fsm(). */ - return lfp->authentication_required || lfp->ciphering_required; + return lfp->authentication_required || + (lfp->ciphering_required && !auth_try_reuse_tuple(lfp->vsub, lfp->key_seq)); } /* Determine if ciphering is required */ @@ -1316,6 +1318,7 @@ static const struct osmo_fsm_state vlr_lu_fsm_states[] = { S(VLR_ULA_S_WAIT_PVLR) | S(VLR_ULA_S_WAIT_IMSI) | S(VLR_ULA_S_WAIT_AUTH) | + S(VLR_ULA_S_WAIT_CIPH) | S(VLR_ULA_S_WAIT_HLR_UPD) | S(VLR_ULA_S_DONE), .name = OSMO_STRINGIFY(VLR_ULA_S_IDLE), @@ -1326,6 +1329,7 @@ static const struct osmo_fsm_state vlr_lu_fsm_states[] = { .out_state_mask = S(VLR_ULA_S_WAIT_PVLR) | S(VLR_ULA_S_WAIT_IMSI) | S(VLR_ULA_S_WAIT_AUTH) | + S(VLR_ULA_S_WAIT_CIPH) | S(VLR_ULA_S_WAIT_HLR_UPD) | S(VLR_ULA_S_DONE), .name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMEISV), @@ -1336,6 +1340,7 @@ static const struct osmo_fsm_state vlr_lu_fsm_states[] = { S(VLR_ULA_E_SEND_ID_NACK), .out_state_mask = S(VLR_ULA_S_WAIT_IMSI) | S(VLR_ULA_S_WAIT_AUTH) | + S(VLR_ULA_S_WAIT_CIPH) | S(VLR_ULA_S_DONE), .name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_PVLR), .action = lu_fsm_wait_pvlr, @@ -1360,6 +1365,7 @@ static const struct osmo_fsm_state vlr_lu_fsm_states[] = { [VLR_ULA_S_WAIT_IMSI] = { .in_event_mask = S(VLR_ULA_E_ID_IMSI), .out_state_mask = S(VLR_ULA_S_WAIT_AUTH) | + S(VLR_ULA_S_WAIT_CIPH) | S(VLR_ULA_S_WAIT_HLR_UPD) | S(VLR_ULA_S_DONE), .name = OSMO_STRINGIFY(VLR_ULA_S_WAIT_IMSI), @@ -1439,6 +1445,7 @@ vlr_loc_update(struct osmo_fsm_inst *parent, const struct osmo_location_area_id *new_lai, bool authentication_required, bool ciphering_required, + uint8_t key_seq, bool is_r99, bool is_utran, bool assign_tmsi) { @@ -1462,6 +1469,7 @@ vlr_loc_update(struct osmo_fsm_inst *parent, lfp->parent_event_data = parent_event_data; lfp->authentication_required = authentication_required; lfp->ciphering_required = ciphering_required; + lfp->key_seq = key_seq; lfp->is_r99 = is_r99; lfp->is_utran = is_utran; lfp->assign_tmsi = assign_tmsi; |