make TSCC Aloha NRand_Wait and Backoff configurable; set TSCC Aloha NRand_Wait to a resaonable value so as to not DDoS the inbound TSCC slot; mark CSBKO_RAND as "handled";

dmr/Control.cpp

@@ -117,7 +117,15 @@ void Control::setOptions(yaml::Node& conf, uint32_t netId, uint8_t siteId, uint8
     yaml::Node systemConf = conf["system"];
     yaml::Node dmrProtocol = conf["protocols"]["dmr"];
 
+    uint8_t nRandWait = (uint8_t)dmrProtocol["nRandWait"].as<uint32_t>(dmr::DEFAULT_NRAND_WAIT);
+    if (nRandWait > 15U)
+        nRandWait = 15U;
+    uint8_t backOff = (uint8_t)dmrProtocol["backOff"].as<uint32_t>(1U);
+    if (backOff > 15U)
+        backOff = 15U;
+
     Slot::setSiteData(netId, siteId, channelId, channelNo);
+    Slot::setAlohaConfig(nRandWait, backOff);
 
     yaml::Node control = dmrProtocol["control"];
     bool enableTSCC = control["enable"].as<bool>(false);
@@ -153,6 +161,10 @@ void Control::setOptions(yaml::Node& conf, uint32_t netId, uint8_t siteId, uint8
 
     if (printOptions) {
         LogInfo("    TSCC Slot: %u", m_tsccSlotNo);
+        if (enableTSCC) {
+            LogInfo("    TSCC Aloha Random Access Wait: %u", nRandWait);
+            LogInfo("    TSCC Aloha Backoff: %u", backOff);
+        }
         LogInfo("    Silence Threshold: %u (%.1f%%)", silenceThreshold, float(silenceThreshold) / 1.41F);
     }
 }

dmr/DMRDefines.h

@@ -133,6 +133,7 @@ namespace dmr
     
     const uint16_t  DMR_LOGICAL_CH_ABSOLUTE = 0xFFFU;
 
+    const uint8_t   DEFAULT_NRAND_WAIT = 8U;
     const uint32_t  DEFAULT_SILENCE_THRESHOLD = 21U;
     const uint32_t  MAX_DMR_VOICE_ERRORS = 141U;
 

dmr/Slot.cpp

@@ -91,6 +91,9 @@ bool Slot::m_voice2 = true;
 
 uint16_t Slot::m_tsccCnt = 0U;
 
+uint8_t Slot::m_alohaNRandWait = DEFAULT_NRAND_WAIT;
+uint8_t Slot::m_alohaBackOff = 1U;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -623,6 +626,7 @@ void Slot::init(uint32_t colorCode, SiteData siteData, bool embeddedLCOnly, bool
 /// <param name="siteId">DMR Site ID.</param>
 /// <param name="channelId">Channel ID.</param>
 /// <param name="channelNo">Channel Number.</param>
+/// <param name="nRandWait"></param>
 void Slot::setSiteData(uint32_t netId, uint8_t siteId, uint8_t channelId, uint32_t channelNo)
 {
     m_siteData = SiteData(SITE_MODEL_SMALL, netId, siteId, 3U, true);
@@ -638,6 +642,17 @@ void Slot::setSiteData(uint32_t netId, uint8_t siteId, uint8_t channelId, uint32
     }
 }
 
+/// <summary>
+/// Sets TSCC Aloha configuration.
+/// </summary>
+/// <param name="nRandWait"></param>
+/// <param name="backOff"></param>
+void Slot::setAlohaConfig(uint8_t nRandWait, uint8_t backOff)
+{
+    m_alohaNRandWait = nRandWait;
+    m_alohaBackOff = backOff;
+}
+
 // ---------------------------------------------------------------------------
 //  Private Class Members
 // ---------------------------------------------------------------------------

dmr/Slot.h

@@ -109,6 +109,8 @@ namespace dmr
             lookups::IdenTableLookup* idenTable, lookups::RSSIInterpolator* rssiMapper, uint32_t jitter);
         /// <summary>Sets local configured site data.</summary>
         static void setSiteData(uint32_t netId, uint8_t siteId, uint8_t channelId, uint32_t channelNo);
+        /// <summary>Sets TSCC Aloha configuration.</summary>
+        static void setAlohaConfig(uint8_t nRandWait, uint8_t backOff);
 
     private:
         friend class Control;
@@ -220,6 +222,9 @@ namespace dmr
 
         static uint16_t m_tsccCnt;
 
+        static uint8_t m_alohaNRandWait;
+        static uint8_t m_alohaBackOff;
+
         /// <summary>Add data frame to the data ring buffer.</summary>
         void addFrame(const uint8_t* data, bool net = false);
 

dmr/lc/CSBK.cpp

@@ -261,7 +261,7 @@ void CSBK::encode(uint8_t* data)
         csbkValue = (csbkValue << 1) + ((m_siteData.netActive()) ? 1U : 0U);        // Site Networked
         csbkValue = (csbkValue << 5) + (m_alohaMask & 0x1FU);                       // MS Mask
         csbkValue = (csbkValue << 2) + 0U;                                          // Service Function
-        csbkValue = (csbkValue << 4) + 0U;                                          // 
+        csbkValue = (csbkValue << 4) + (m_nRandWait & 0x0FU);                       // Random Access Wait
         csbkValue = (csbkValue << 1) + ((m_siteData.requireReg()) ? 1U : 0U);       // Require Registration
         csbkValue = (csbkValue << 4) + (m_backoffNo & 0x0FU);                       // Backoff Number
         csbkValue = (csbkValue << 16) + m_siteData.systemIdentity();                // Site Identity
@@ -463,6 +463,7 @@ CSBK::CSBK(SiteData siteData) :
     m_priority(0U),
     m_broadcast(false),
     m_backoffNo(1U),
+    m_nRandWait(DEFAULT_NRAND_WAIT),
     m_serviceData(0U),
     m_serviceType(0U),
     m_targetAddress(TGT_ADRS_TGID),

dmr/lc/CSBK.h

@@ -108,6 +108,8 @@ namespace dmr
             /** Tier III */
             /// <summary>Backoff Number.</summary>
             __PROPERTY(uint8_t, backoffNo, BackoffNo);
+            /// <summary>Random Access Wait Delay.</summary>
+            __PROPERTY(uint8_t, nRandWait, NRandWait);
 
             /// <summary>Service Data.</summary>
             __PROPERTY(uint8_t, serviceData, ServiceData);

dmr/packet/ControlSignaling.cpp

@@ -146,6 +146,8 @@ bool ControlSignaling::process(uint8_t* data, uint32_t len)
 
                 ::ActivityLog("DMR", true, "Slot %u call alert request from %u to %u", m_slot->m_slotNo, srcId, dstId);
             } else {
+                handled = true;
+                
                 if (m_verbose) {
                     LogMessage(LOG_RF, "DMR Slot %u, DT_CSBK, CSBKO_RAND (Random Access), emerg = %u, prio = %u, serviceType = %02X, serviceData = %02X, srcId = %u, dstId = %u",
                         m_slot->m_slotNo, csbk.getEmergency(), csbk.getPriority(), csbk.getServiceType(), csbk.getServiceData(), csbk.getSrcId(), csbk.getDstId());
@@ -557,6 +559,9 @@ void ControlSignaling::writeRF_TSCC_Aloha()
     csbk.setCSBKO(CSBKO_ALOHA);
     csbk.setFID(FID_ETSI);
 
+    csbk.setNRandWait(m_slot->m_alohaNRandWait);
+    csbk.setBackoffNo(m_slot->m_alohaBackOff);
+
     // Regenerate the CSBK data
     csbk.encode(data + 2U);