lora: add best packet filter patch to v1.5 packet forwarder

1 files changed, 38 insertions, 19 deletions

diff --git a/recipes-connectivity/lora/lora-packet-forwarder/lora-packet-forwarder-dedup-rx.patch b/recipes-connectivity/lora/lora-packet-forwarder/lora-packet-forwarder-dedup-rx.patch
index b80bb26..c368033 100644
--- a/recipes-connectivity/lora/lora-packet-forwarder/lora-packet-forwarder-dedup-rx.patch
+++ b/recipes-connectivity/lora/lora-packet-forwarder/lora-packet-forwarder-dedup-rx.patch
@@ -1,39 +1,59 @@
 diff --git a/lora_pkt_fwd/src/lora_pkt_fwd.c b/lora_pkt_fwd/src/lora_pkt_fwd.c
-index 801f28d..7c94308 100644
+index 801f28d..c35c64f 100644
 --- a/lora_pkt_fwd/src/lora_pkt_fwd.c
 +++ b/lora_pkt_fwd/src/lora_pkt_fwd.c
-@@ -1536,6 +1556,41 @@ void thread_up(void) {
+@@ -126,8 +126,9 @@ volatile bool quit_sig = false; /* 1 -> application terminates without shutting
+ static bool fwd_valid_pkt = true; /* packets with PAYLOAD CRC OK are forwarded */
+ static bool fwd_error_pkt = false; /* packets with PAYLOAD CRC ERROR are NOT forwarded */
+ static bool fwd_nocrc_pkt = false; /* packets with NO PAYLOAD CRC are NOT forwarded */
++static bool fwd_best_pkt = true; /* duplicate packets with low SNR are NOT forwarded */
+ 
+ /* network configuration variables */
+ static uint64_t lgwm = 0; /* Lora gateway MAC address */
+ static char serv_addr[64] = STR(DEFAULT_SERVER); /* address of the server (host name or IPv4/IPv6) */
+ static char serv_port_up[8] = STR(DEFAULT_PORT_UP); /* server port for upstream traffic */
+@@ -731,6 +742,12 @@ static int parse_gateway_configuration(const char * conf_file) {
+     }
+ 
+     /* packet filtering parameters */
++    val = json_object_get_value(conf_obj, "best_packet_filter");
++    if (json_value_get_type(val) == JSONBoolean) {
++        fwd_best_pkt = (bool)json_value_get_boolean(val);
++    }
++    MSG("INFO: duplicate packets received with low SNR will%s be forwarded\n", (!fwd_best_pkt ? "" : " NOT"));
++
+     val = json_object_get_value(conf_obj, "forward_crc_valid");
+     if (json_value_get_type(val) == JSONBoolean) {
+         fwd_valid_pkt = (bool)json_value_get_boolean(val);
+@@ -1536,6 +1562,38 @@ void thread_up(void) {
          memcpy((void *)(buff_up + buff_index), (void *)"{\"rxpk\":[", 9);
          buff_index += 9;
  
-+        if (nb_pkt > 1) {
++        if (fwd_best_pkt && nb_pkt > 1) {
 +            uint32_t check_addr = 0;
++            uint32_t check_mic = 0;
 +            uint16_t check_fcnt = 0;
 +            float check_snr = -30.0;
 +
 +            for (i=0; i < nb_pkt; ++i) {
 +                p = &rxpkt[i];
-+                check_addr  = p->payload[1];
-+               check_addr |= p->payload[2] << 8;
-+               check_addr |= p->payload[3] << 16;
-+               check_addr |= p->payload[4] << 24;
++                if (p->size < 12)
++                    continue;
++
++                memcpy(&check_addr, p->payload + 1, 4);
++                memcpy(&check_fcnt, p->payload + 6, 2);
++                memcpy(&check_mic, p->payload + p->size - 4, 4);
 +
-+                check_fcnt  = p->payload[6];
-+                check_fcnt |= p->payload[7] << 8;
-+                
 +                check_snr = p->snr;
 +
 +                for (j=0; j < nb_pkt; ++j) {
 +                    p = &rxpkt[j];
-+                    mote_addr  = p->payload[1];
-+                    mote_addr |= p->payload[2] << 8;
-+                    mote_addr |= p->payload[3] << 16;
-+                    mote_addr |= p->payload[4] << 24;
-+
-+                    mote_fcnt  = p->payload[6];
-+                    mote_fcnt |= p->payload[7] << 8;
 +
-+                    if (check_addr == mote_addr && check_fcnt == mote_fcnt && p->snr < check_snr) {
++                    if (p->size >= 12
++                        && memcmp(&check_addr, p->payload + 1, 4) == 0
++                        && memcmp(&check_fcnt, p->payload + 6, 2) == 0
++                        && memcmp(&check_mic, p->payload + p->size - 4, 4) == 0
++                        && p->snr < check_snr) {
 +                        // set status of duplicate packets rx'd on wrong channel
 +                        p->status = 1;
 +                    }
@@ -44,4 +64,3 @@ index 801f28d..7c94308 100644
          /* serialize Lora packets metadata and payload */
          pkt_in_dgram = 0;
          for (i=0; i < nb_pkt; ++i) {
-