| =========================== |
| "Raw" packet socket support |
| =========================== |
| |
| Packet sockets (:c:macro:`AF_PACKET`) allow receiving and transmitting frames |
| without a transport protocol in between. Frames received are copied into a |
| packet socket tap before they enter the network. Data written into a packet |
| socket will bypass the network altogether and be placed in the transmission |
| buffer of the network interface driver. |
| |
| Configuration Options |
| ===================== |
| |
| ``CONFIG_NET_PKT_PREALLOC_CONNS`` |
| Number of preallocated packet connections (all tasks). |
| ``CONFIG_NET_PKT_ALLOC_CONNS`` |
| Dynamic memory allocations for packet connections. |
| ``CONFIG_NET_PKT_MAX_CONNS`` |
| Maximum number of packet connections. |
| |
| Usage |
| ===== |
| |
| .. code-block:: c |
| |
| struct sockaddr_ll addr; |
| uint8_t buffer[BUFSIZE]; |
| int sd = socket(AF_PACKET, SOCK_RAW, 0); /* Create a packet socket */ |
| |
| addr.sll_family = AF_PACKET; |
| addr.sll_ifindex = if_nametoindex("eth0"); |
| bind(sd, (FAR struct sockaddr *)&addr, sizeof(addr)); /* Bind to device */ |
| |
| recv(sd, buffer, sizeof(buffer), 0); /* read(sd, buffer, sizeof(buffer)); */ |
| send(sd, buffer, sizeof(buffer), 0); /* write(sd, buffer, sizeof(buffer)); */ |
| |
| close(sd); /* Close the socket */ |
