<p>laforge <strong>submitted</strong> this change.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bsc/+/18565">View Change</a></p><div style="white-space:pre-wrap">Approvals:
laforge: Looks good to me, approved
pespin: Looks good to me, but someone else must approve
Jenkins Builder: Verified
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">abis_nm: fix ARFCN list encoding in Set Channel Attributes<br><br>3GPP TS 12.21 defines coding of 'ARFCN List' attribute as follows:<br><br> +---------------------------+--------------------+<br> | Attribute Identifier | 1st octet |<br> +---------------------------+--------------------+<br> | Length | 2-3 octets |<br> +---------------------------+--------------------+<br> | ARFCN1 | 4-5 octets |<br> +---------------------------+--------------------+<br> | ... | ... |<br> +---------------------------+--------------------+<br> | ARFCNn | (n * 2 - 3) octets |<br> +---------------------------+--------------------+<br><br>so this is basically TL16V, where L16 is the length of V.<br><br>In the Siemens dialect of OML coding rules are different though:<br><br> +---------------------------+--------------------+<br> | Attribute Identifier | 1st octet |<br> +---------------------------+--------------------+<br> | ARFCN count | 2nd octet |<br> +---------------------------+--------------------+<br> | ARFCN1 | 4-5 octets |<br> +---------------------------+--------------------+<br> | ... | ... |<br> +---------------------------+--------------------+<br> | ARFCNn | (n * 2 - 2) octets |<br> +---------------------------+--------------------+<br><br>so this is TCV, where C is the amount of ARFCNs in V.<br><br>This change fixes encoding of 'ARFCN List' for other dialects,<br>in particular encoding of the 'Length' field (1 vs 2 octets).<br>I verified the results in Wireshark (generic 3GPP TS 12.21<br>and ip.access dialect), everything looks good.<br><br>Change-Id: Iec1826f55459ac8e9355328a1a6bb0949874db60<br>Related: OS#4545<br>---<br>M src/osmo-bsc/abis_nm.c<br>1 file changed, 28 insertions(+), 11 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/src/osmo-bsc/abis_nm.c b/src/osmo-bsc/abis_nm.c</span><br><span>index db2879f..d503f2a 100644</span><br><span>--- a/src/osmo-bsc/abis_nm.c</span><br><span>+++ b/src/osmo-bsc/abis_nm.c</span><br><span>@@ -2019,26 +2019,43 @@</span><br><span> </span><br><span> msgb_tv_put(msg, NM_ATT_CHAN_COMB, chan_comb);</span><br><span> if (ts->hopping.enabled) {</span><br><span style="color: hsl(0, 100%, 40%);">- unsigned int i;</span><br><span style="color: hsl(0, 100%, 40%);">- uint8_t *len;</span><br><span style="color: hsl(120, 100%, 40%);">+ unsigned int i, n;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint16_t *u16 = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t *u8 = NULL;</span><br><span> </span><br><span> msgb_tv_put(msg, NM_ATT_HSN, ts->hopping.hsn);</span><br><span> msgb_tv_put(msg, NM_ATT_MAIO, ts->hopping.maio);</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- /* build the ARFCN list */</span><br><span> msgb_put_u8(msg, NM_ATT_ARFCN_LIST);</span><br><span style="color: hsl(0, 100%, 40%);">- len = msgb_put(msg, 1);</span><br><span style="color: hsl(0, 100%, 40%);">- *len = 0;</span><br><span style="color: hsl(0, 100%, 40%);">- for (i = 0; i < ts->hopping.arfcns.data_len*8; i++) {</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* 3GPP TS 12.21 defines this IE as TL16V */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bts->type != GSM_BTS_TYPE_BS11)</span><br><span style="color: hsl(120, 100%, 40%);">+ u16 = (uint16_t *) msgb_put(msg, 2);</span><br><span style="color: hsl(120, 100%, 40%);">+ else /* ... but BS-11 wants TLV instead */</span><br><span style="color: hsl(120, 100%, 40%);">+ u8 = (uint8_t *) msgb_put(msg, 1);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* build the ARFCN list from pre-computed bitmap */</span><br><span style="color: hsl(120, 100%, 40%);">+ for (i = 0, n = 0; i < ts->hopping.arfcns.data_len*8; i++) {</span><br><span> if (bitvec_get_bit_pos(&ts->hopping.arfcns, i)) {</span><br><span> msgb_put_u16(msg, i);</span><br><span style="color: hsl(0, 100%, 40%);">- /* At least BS-11 wants a TLV16 here */</span><br><span style="color: hsl(0, 100%, 40%);">- if (bts->type == GSM_BTS_TYPE_BS11)</span><br><span style="color: hsl(0, 100%, 40%);">- *len += 1;</span><br><span style="color: hsl(0, 100%, 40%);">- else</span><br><span style="color: hsl(0, 100%, 40%);">- *len += sizeof(uint16_t);</span><br><span style="color: hsl(120, 100%, 40%);">+ n += 1;</span><br><span> }</span><br><span> }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* BS-11 cannot handle more than 255 ARFCNs, because L is 8 bit.</span><br><span style="color: hsl(120, 100%, 40%);">+ * This is unlikely to happen, but better check than sorry... */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bts->type == GSM_BTS_TYPE_BS11 && n > 0xff) {</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGPFOH(DNM, LOGL_ERROR, foh, "%s cannot handle %u (more than 255) "</span><br><span style="color: hsl(120, 100%, 40%);">+ "hopping channels\n", gsm_bts_name(bts), n);</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_free(msg);</span><br><span style="color: hsl(120, 100%, 40%);">+ return -EINVAL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* 3GPP TS 12.21 defines L as length of the V part (in octets) */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bts->type != GSM_BTS_TYPE_BS11)</span><br><span style="color: hsl(120, 100%, 40%);">+ *u16 = htons(n * sizeof(*u16));</span><br><span style="color: hsl(120, 100%, 40%);">+ else /* ... BS-11 wants the number of channels instead */</span><br><span style="color: hsl(120, 100%, 40%);">+ *u8 = n;</span><br><span> }</span><br><span> msgb_tv_put(msg, NM_ATT_TSC, gsm_ts_tsc(ts)); /* training sequence */</span><br><span> if (bts->type == GSM_BTS_TYPE_BS11)</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-bsc/+/18565">change 18565</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/c/osmo-bsc/+/18565"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: osmo-bsc </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: Iec1826f55459ac8e9355328a1a6bb0949874db60 </div>
<div style="display:none"> Gerrit-Change-Number: 18565 </div>
<div style="display:none"> Gerrit-PatchSet: 4 </div>
<div style="display:none"> Gerrit-Owner: fixeria <vyanitskiy@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder </div>
<div style="display:none"> Gerrit-Reviewer: fixeria <vyanitskiy@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: laforge <laforge@osmocom.org> </div>
<div style="display:none"> Gerrit-Reviewer: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: merged </div>