ESP32 receive broadcast UDP packets
Posted: Mon Feb 08, 2021 1:55 pm
Hello,
I'm attempting to configure a number of connected ESP32 stations using a single ESP32 AP. The easiest way for me to do this would be to send a single broadcast UDP packet to 255.255.255.255. However, my stations who are listening with an open UDP port are not receiving broadcast data at all. Is there something else I need to configure on the station/AP for this to be possible?
Here's my current station UDP listening task:
I'm attempting to configure a number of connected ESP32 stations using a single ESP32 AP. The easiest way for me to do this would be to send a single broadcast UDP packet to 255.255.255.255. However, my stations who are listening with an open UDP port are not receiving broadcast data at all. Is there something else I need to configure on the station/AP for this to be possible?
Here's my current station UDP listening task:
Code: Select all
static void udp_listen_task(void *pvParameters)
{
while (1) {
struct sockaddr_in dest_addr;
dest_addr.sin_addr.s_addr = htonl(INADDR_ANY);
dest_addr.sin_family = AF_INET;
dest_addr.sin_port = htons(PORT);
int addr_family = AF_INET;
int ip_protocol = IPPROTO_IP;
inet_ntoa_r(dest_addr.sin_addr, addr_str, sizeof(addr_str) - 1);
int sock = socket(addr_family, SOCK_DGRAM, ip_protocol);
if (sock < 0) {
ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
break;
}
//ESP_LOGI(TAG, "Socket created");
int err = bind(sock, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
if (err < 0) {
ESP_LOGE(TAG, "Socket unable to bind: err %d", err);
}
while (1) {
struct sockaddr_in6 source_addr;
socklen_t socklen = sizeof(source_addr);
int len = recvfrom(sock, &controller_msg, sizeof(controller_msg), 0, (struct sockaddr *)&source_addr, &socklen);
//Error occurred during receiving
if (len < 0) {
ESP_LOGE(TAG, "recvfrom failed: errno %d", errno);
break;
}
// Data received
else {
// Get the sender's ip address as string
if (source_addr.sin6_family == PF_INET) {
inet_ntoa_r(((struct sockaddr_in *)&source_addr)->sin_addr.s_addr, addr_str, sizeof(addr_str) - 1);
} else if (source_addr.sin6_family == PF_INET6) {
inet6_ntoa_r(source_addr.sin6_addr, addr_str, sizeof(addr_str) - 1);
}
// Post event to act on message
xEventGroupSetBits(conn_evt, CONN_EVT_UDP_RECEIVED);
}
}
if (sock != -1) {
ESP_LOGE(TAG, "Shutting down socket and restarting...");
shutdown(sock, 0);
close(sock);
}
}
vTaskDelete(NULL);
}