/**************************************************************************** * net/icmp/icmp_conn.c * * Copyright (C) 2017 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote * products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "devif/devif.h" #include "icmp/icmp.h" #ifdef CONFIG_NET_ICMP_SOCKET /**************************************************************************** * Private Data ****************************************************************************/ /* The array containing all IPPROTO_ICMP socket connections */ static struct icmp_conn_s g_icmp_connections[CONFIG_NET_ICMP_NCONNS]; /* A list of all free IPPROTO_ICMP socket connections */ static dq_queue_t g_free_icmp_connections; static sem_t g_free_sem; /* A list of all allocated IPPROTO_ICMP socket connections */ static dq_queue_t g_active_icmp_connections; /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: icmp_sock_initialize * * Description: * Initialize the IPPROTO_ICMP socket connection structures. Called once * and only from the network initialization layer. * ****************************************************************************/ void icmp_sock_initialize(void) { int i; /* Initialize the queues */ dq_init(&g_free_icmp_connections); dq_init(&g_active_icmp_connections); nxsem_init(&g_free_sem, 0, 1); for (i = 0; i < CONFIG_NET_ICMP_NCONNS; i++) { /* Move the connection structure to the free list */ dq_addlast(&g_icmp_connections[i].node, &g_free_icmp_connections); } } /**************************************************************************** * Name: icmp_alloc * * Description: * Allocate a new, uninitialized IPPROTO_ICMP socket connection structure. * This is normally something done by the implementation of the socket() * interface. * ****************************************************************************/ FAR struct icmp_conn_s *icmp_alloc(void) { FAR struct icmp_conn_s *conn = NULL; int ret; /* The free list is protected by a semaphore (that behaves like a mutex). */ ret = net_lockedwait(&g_free_sem); if (ret >= 0) { conn = (FAR struct icmp_conn_s *)dq_remfirst(&g_free_icmp_connections); if (conn != NULL) { /* Clear the connection structure */ memset(conn, 0, sizeof(struct icmp_conn_s)); /* Enqueue the connection into the active list */ dq_addlast(&conn->node, &g_active_icmp_connections); } nxsem_post(&g_free_sem); } return conn; } /**************************************************************************** * Name: icmp_free * * Description: * Free a IPPROTO_ICMP socket connection structure that is no longer in * use. This should be done by the implementation of close(). * ****************************************************************************/ void icmp_free(FAR struct icmp_conn_s *conn) { int ret; /* The free list is protected by a semaphore (that behaves like a mutex). */ DEBUGASSERT(conn->crefs == 0); /* Take the semaphore (perhaps waiting) */ while ((ret = net_lockedwait(&g_free_sem)) < 0) { /* The only case that an error should occur here is if * the wait was awakened by a signal. */ DEBUGASSERT(ret == -EINTR || ret == -ECANCELED); } UNUSED(ret); /* Is this the last reference on the connection? It might not be if the * socket was cloned. */ if (conn->crefs > 1) { /* No.. just decrement the reference count */ conn->crefs--; } else { /* Remove the connection from the active list */ dq_rem(&conn->node, &g_active_icmp_connections); /* Free the connection */ dq_addlast(&conn->node, &g_free_icmp_connections); nxsem_post(&g_free_sem); } } /**************************************************************************** * Name: icmp_active() * * Description: * Find a connection structure that is the appropriate connection to be * used with the provided ECHO request ID. * * Assumptions: * This function is called from network logic at with the network locked. * ****************************************************************************/ FAR struct icmp_conn_s *icmp_active(uint16_t id) { FAR struct icmp_conn_s *conn = (FAR struct icmp_conn_s *)g_active_icmp_connections.head; while (conn != NULL) { /* FIXME lmac in conn should have been set by icmp_bind() */ if (id == conn->id) { /* Matching connection found.. return a reference to it */ break; } /* Look at the next active connection */ conn = (FAR struct icmp_conn_s *)conn->node.flink; } return conn; } /**************************************************************************** * Name: icmp_nextconn * * Description: * Traverse the list of allocated packet connections * * Assumptions: * This function is called from network logic at with the network locked. * ****************************************************************************/ FAR struct icmp_conn_s *icmp_nextconn(FAR struct icmp_conn_s *conn) { if (conn == NULL) { return (FAR struct icmp_conn_s *)g_active_icmp_connections.head; } else { return (FAR struct icmp_conn_s *)conn->node.flink; } } /**************************************************************************** * Name: icmp_findconn * * Description: * Find an ICMP connection structure that is expecting a ICMP ECHO response * with this ID from this device * * Assumptions: * This function is called from network logic at with the network locked. * ****************************************************************************/ FAR struct icmp_conn_s *icmp_findconn(FAR struct net_driver_s *dev, uint8_t id) { FAR struct icmp_conn_s *conn; for (conn = icmp_nextconn(NULL); conn != NULL; conn = icmp_nextconn(conn)) { if (conn->id == id && conn->dev == dev && conn->nreqs > 0) { return conn; } } return conn; } #endif /* CONFIG_NET_ICMP */