diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/osmo-bsc/osmo_bsc_bssap.c | 48 |
1 files changed, 39 insertions, 9 deletions
diff --git a/src/osmo-bsc/osmo_bsc_bssap.c b/src/osmo-bsc/osmo_bsc_bssap.c index 431125024..93e9274a0 100644 --- a/src/osmo-bsc/osmo_bsc_bssap.c +++ b/src/osmo-bsc/osmo_bsc_bssap.c @@ -233,10 +233,11 @@ static int bssmap_handle_paging(struct bsc_msc_data *msc, struct tlv_parsed tp; char mi_string[GSM48_MI_SIZE]; uint32_t tmsi = GSM_RESERVED_TMSI; - unsigned int lac = GSM_LAC_RESERVED_ALL_BTS; + unsigned int lac; uint8_t data_length; const uint8_t *data; uint8_t chan_needed = RSL_CHANNEED_ANY; + uint8_t cell_ident; tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l4h + 1, payload_length - 1, 0, 0); @@ -265,21 +266,50 @@ static int bssmap_handle_paging(struct bsc_msc_data *msc, TLVP_VAL(&tp, GSM0808_IE_IMSI), TLVP_LEN(&tp, GSM0808_IE_IMSI)); /* - * parse the cell identifier list + * There are various cell identifier list types defined at 3GPP TS ยง 08.08, we don't support all + * of them yet. To not disrupt paging operation just because we're lacking some implementation, + * interpret any unknown cell identifier type as "page the entire BSS". */ data_length = TLVP_LEN(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST); data = TLVP_VAL(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST); - /* - * Support paging to all network or one BTS at one LAC - */ - if (data_length == 3 && data[0] == CELL_IDENT_LAC) { - lac = osmo_load16be(&data[1]); - } else if (data_length > 1 || (data[0] & 0x0f) != CELL_IDENT_BSS) { - LOGP(DMSC, LOGL_ERROR, "Unsupported Cell Identifier List: %s\n", osmo_hexdump(data, data_length)); + if (data_length < 1) { + LOGP(DMSC, LOGL_ERROR, "Paging IMSI %s: Zero length Cell Identifier List\n", + mi_string); return -1; } + cell_ident = data[0] & 0xf; + + /* Default fallback: page entire BSS */ + lac = GSM_LAC_RESERVED_ALL_BTS; + + switch (cell_ident) { + case CELL_IDENT_LAC: + if (data_length != 3) { + LOGP(DMSC, LOGL_ERROR, "Paging IMSI %s: Cell Identifier List for LAC (0x%x)" + " has invalid length: %u, paging entire BSS instead (%s)\n", + mi_string, CELL_IDENT_LAC, data_length, osmo_hexdump(data, data_length)); + break; + } + lac = osmo_load16be(&data[1]); + break; + + case CELL_IDENT_BSS: + if (data_length != 1) { + LOGP(DMSC, LOGL_ERROR, "Paging IMSI %s: Cell Identifier List for BSS (0x%x)" + " has invalid length: %u, paging entire BSS anyway (%s)\n", + mi_string, CELL_IDENT_BSS, data_length, osmo_hexdump(data, data_length)); + } + break; + + default: + LOGP(DMSC, LOGL_NOTICE, "Paging IMSI %s: unimplemented Cell Identifier List (0x%x)," + " paging entire BSS instead (%s)\n", + mi_string, cell_ident, osmo_hexdump(data, data_length)); + break; + } + if (TLVP_PRESENT(&tp, GSM0808_IE_CHANNEL_NEEDED) && TLVP_LEN(&tp, GSM0808_IE_CHANNEL_NEEDED) == 1) chan_needed = TLVP_VAL(&tp, GSM0808_IE_CHANNEL_NEEDED)[0] & 0x03; |