diff options
| author | Neels Hofmeyr <neels@hofmeyr.de> | 2020-07-10 10:41:59 +0200 |
|---|---|---|
| committer | laforge <laforge@osmocom.org> | 2020-07-16 12:03:19 +0000 |
| commit | 954ee0a4b8a3505ac5014c4099b9b3655c872efa (patch) | |
| tree | ce64b63910c8c5dc12131788f5317c91695945b6 | |
| parent | 9899bc9d118a966ee706af3abd8194595d915080 (diff) | |
RR Release Cell selection IE: fix repeated EARFCNs encoding
3GPP 44.018 10.5.2.1e defines the EARFCNs encoded in the 'Cell selection
indicator after release of all TCH and SDCCH IE' as follows:
<Cell Selection Indicator after release of all TCH and SDCCH value part> ::=
[...]
| 011 { 1 <E-UTRAN Description : < E-UTRAN Description struct >> } ** 0
So after a 3-bit discriminator of '3' there can be multiple E-UTRAN
Descriptions, and each of them starts with a '1' bit to indicate that another
item follows. Finally there is a '0' bit to indicate the list end.
Before this patch, osmo-bsc only encoded the first '1' bit, and failed to
repeat this before each following E-UTRAN Description. Fix that by moving the
'1' encoding into the loop.
The final '0' was missing. Add it.
With these changes, adjust the size calculation in
CELL_SEL_IND_AFTER_REL_MAX_BITS to match.
Also fix CELL_SEL_IND_AFTER_REL_MAX_BYTES by using OSMO_BYTES_FOR_BITS()
instead of the inaccurate (n/8)+1.
A test for this is in I882c5e1f70bcc4833fc837a95c900ce291919cc5
(osmo-ttcn3-hacks).
Related: SYS#4871 SYS#4872
Change-Id: I59e427e4ebb1c6af99b27a15c40fed82457ac8ab
| -rw-r--r-- | src/osmo-bsc/gsm_04_08_rr.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/src/osmo-bsc/gsm_04_08_rr.c b/src/osmo-bsc/gsm_04_08_rr.c index f47c31f41..f425b1636 100644 --- a/src/osmo-bsc/gsm_04_08_rr.c +++ b/src/osmo-bsc/gsm_04_08_rr.c @@ -238,8 +238,8 @@ static void mr_config_for_ms(struct gsm_lchan *lchan, struct msgb *msg) } -#define CELL_SEL_IND_AFTER_REL_MAX_BITS (4+MAX_EARFCN_LIST*19) -#define CELL_SEL_IND_AFTER_REL_MAX_BYTES ((CELL_SEL_IND_AFTER_REL_MAX_BITS/8)+1) +#define CELL_SEL_IND_AFTER_REL_MAX_BITS (3+MAX_EARFCN_LIST*20+1) +#define CELL_SEL_IND_AFTER_REL_MAX_BYTES OSMO_BYTES_FOR_BITS(CELL_SEL_IND_AFTER_REL_MAX_BITS) /* Generate a CSN.1 encoded "Cell Selection Indicator after release of all TCH and SDCCH" * as per TF 44.018 version 15.3.0 Table 10.5.2.1e.1. This only generates the "value" @@ -255,17 +255,18 @@ static int generate_cell_sel_ind_after_rel(uint8_t *out, unsigned int out_len, c /* E-UTRAN Description */ bitvec_set_uint(&bv, 3, 3); - bitvec_set_bit(&bv, 1); for (i = 0; i < MAX_EARFCN_LIST; i++) { const struct osmo_earfcn_si2q *e = &bts->si_common.si2quater_neigh_list; if (e->arfcn[i] == OSMO_EARFCN_INVALID) continue; - if (bitvec_tailroom_bits(&bv) < 19) { + /* tailroom must fit one more EARFCN (20 bits), plus the final list term bit. */ + if (bitvec_tailroom_bits(&bv) < 21) { LOGP(DRR, LOGL_NOTICE, "%s: Not enough room to store EARFCN %u in the " "Cell Selection Indicator IE\n", gsm_bts_name(bts), e->arfcn[i]); } else { + bitvec_set_bit(&bv, 1); bitvec_set_uint(&bv, e->arfcn[i], 16); /* No "Measurement Bandwidth" */ bitvec_set_bit(&bv, 0); @@ -276,6 +277,9 @@ static int generate_cell_sel_ind_after_rel(uint8_t *out, unsigned int out_len, c } } + /* list term */ + bitvec_set_bit(&bv, 0); + rc = bitvec_used_bytes(&bv); if (rc == 1) { |