diff options
Diffstat (limited to 'nuttx/net/uip/uip_udpconn.c')
| -rw-r--r-- | nuttx/net/uip/uip_udpconn.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/nuttx/net/uip/uip_udpconn.c b/nuttx/net/uip/uip_udpconn.c new file mode 100644 index 000000000..3c4ee5add --- /dev/null +++ b/nuttx/net/uip/uip_udpconn.c @@ -0,0 +1,492 @@ +/**************************************************************************** + * net/uip/uip_udpconn.c + * + * Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * Large parts of this file were leveraged from uIP logic: + * + * Copyright (c) 2001-2003, Adam Dunkels. + * All rights reserved. + * + * 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Compilation Switches + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#if defined(CONFIG_NET) && defined(CONFIG_NET_UDP) + +#include <stdint.h> +#include <string.h> +#include <semaphore.h> +#include <assert.h> +#include <errno.h> +#include <debug.h> + +#include <arch/irq.h> + +#include <nuttx/net/uip/uipopt.h> +#include <nuttx/net/uip/uip.h> +#include <nuttx/net/uip/uip-arch.h> + +#include "uip_internal.h" + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/* The array containing all uIP UDP connections. */ + +struct uip_udp_conn g_udp_connections[CONFIG_NET_UDP_CONNS]; + +/* A list of all free UDP connections */ + +static dq_queue_t g_free_udp_connections; +static sem_t g_free_sem; + +/* A list of all allocated UDP connections */ + +static dq_queue_t g_active_udp_connections; + +/* Last port used by a UDP connection connection. */ + +static uint16_t g_last_udp_port; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: _uip_semtake() and _uip_semgive() + * + * Description: + * Take/give semaphore + * + ****************************************************************************/ + +static inline void _uip_semtake(sem_t *sem) +{ + /* Take the semaphore (perhaps waiting) */ + + while (uip_lockedwait(sem) != 0) + { + /* The only case that an error should occur here is if + * the wait was awakened by a signal. + */ + + ASSERT(*get_errno_ptr() == EINTR); + } +} + +#define _uip_semgive(sem) sem_post(sem) + +/**************************************************************************** + * Name: uip_find_conn() + * + * Description: + * Find the UDP connection that uses this local port number. Called only + * from user user level code, but with interrupts disabled. + * + ****************************************************************************/ + +static struct uip_udp_conn *uip_find_conn(uint16_t portno) +{ + int i; + + /* Now search each connection structure.*/ + + for (i = 0; i < CONFIG_NET_UDP_CONNS; i++) + { + if (g_udp_connections[ i ].lport == portno) + { + return &g_udp_connections[ i ]; + } + } + + return NULL; +} + +/**************************************************************************** + * Name: uip_selectport() + * + * Description: + * Select an unused port number. + * + * NOTE that in prinicple this function could fail if there is no available + * port number. There is no check for that case and it would actually + * in an infinite loop if that were the case. In this simple, small UDP + * implementation, it is reasonable to assume that that error cannot happen + * and that a port number will always be available. + * + * Input Parameters: + * None + * + * Return: + * Next available port number + * + ****************************************************************************/ + +static uint16_t uip_selectport(void) +{ + uint16_t portno; + + /* Find an unused local port number. Loop until we find a valid + * listen port number that is not being used by any other connection. + */ + + uip_lock_t flags = uip_lock(); + do + { + /* Guess that the next available port number will be the one after + * the last port number assigned. + */ + + ++g_last_udp_port; + + /* Make sure that the port number is within range */ + + if (g_last_udp_port >= 32000) + { + g_last_udp_port = 4096; + } + } + while (uip_find_conn(htons(g_last_udp_port))); + + /* Initialize and return the connection structure, bind it to the + * port number + */ + + portno = g_last_udp_port; + uip_unlock(flags); + + return portno; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: uip_udpinit() + * + * Description: + * Initialize the UDP connection structures. Called once and only from + * the UIP layer. + * + ****************************************************************************/ + +void uip_udpinit(void) +{ + int i; + + /* Initialize the queues */ + + dq_init(&g_free_udp_connections); + dq_init(&g_active_udp_connections); + sem_init(&g_free_sem, 0, 1); + + for (i = 0; i < CONFIG_NET_UDP_CONNS; i++) + { + /* Mark the connection closed and move it to the free list */ + + g_udp_connections[i].lport = 0; + dq_addlast(&g_udp_connections[i].node, &g_free_udp_connections); + } + + g_last_udp_port = 1024; +} + +/**************************************************************************** + * Name: uip_udpalloc() + * + * Description: + * Alloc a new, uninitialized UDP connection structure. + * + ****************************************************************************/ + +struct uip_udp_conn *uip_udpalloc(void) +{ + struct uip_udp_conn *conn; + + /* The free list is only accessed from user, non-interrupt level and + * is protected by a semaphore (that behaves like a mutex). + */ + + _uip_semtake(&g_free_sem); + conn = (struct uip_udp_conn *)dq_remfirst(&g_free_udp_connections); + if (conn) + { + /* Make sure that the connection is marked as uninitialized */ + + conn->lport = 0; + } + _uip_semgive(&g_free_sem); + return conn; +} + +/**************************************************************************** + * Name: uip_udpfree() + * + * Description: + * Free a UDP connection structure that is no longer in use. This should be + * done by the implementation of close(). uip_udpdisable must have been + * previously called. + * + ****************************************************************************/ + +void uip_udpfree(struct uip_udp_conn *conn) +{ + /* The free list is only accessed from user, non-interrupt level and + * is protected by a semaphore (that behaves like a mutex). + */ + + DEBUGASSERT(conn->crefs == 0); + + _uip_semtake(&g_free_sem); + conn->lport = 0; + dq_addlast(&conn->node, &g_free_udp_connections); + _uip_semgive(&g_free_sem); +} + +/**************************************************************************** + * Name: uip_udpactive() + * + * Description: + * Find a connection structure that is the appropriate + * connection to be used withi the provided TCP/IP header + * + * Assumptions: + * This function is called from UIP logic at interrupt level + * + ****************************************************************************/ + +struct uip_udp_conn *uip_udpactive(struct uip_udpip_hdr *buf) +{ + struct uip_udp_conn *conn = (struct uip_udp_conn *)g_active_udp_connections.head; + + while (conn) + { + /* If the local UDP port is non-zero, the connection is considered + * to be used. If so, the local port number is checked against the + * destination port number in the received packet. If the two port + * numbers match, the remote port number is checked if the + * connection is bound to a remote port. Finally, if the + * connection is bound to a remote IP address, the source IP + * address of the packet is checked. + */ + + if (conn->lport != 0 && buf->destport == conn->lport && + (conn->rport == 0 || buf->srcport == conn->rport) && + (uip_ipaddr_cmp(conn->ripaddr, g_allzeroaddr) || + uip_ipaddr_cmp(conn->ripaddr, g_alloneaddr) || + uiphdr_ipaddr_cmp(buf->srcipaddr, &conn->ripaddr))) + { + /* Matching connection found.. return a reference to it */ + + break; + } + + /* Look at the next active connection */ + + conn = (struct uip_udp_conn *)conn->node.flink; + } + + return conn; +} + +/**************************************************************************** + * Name: uip_nextudpconn() + * + * Description: + * Traverse the list of allocated UDP connections + * + * Assumptions: + * This function is called from UIP logic at interrupt level (or with + * interrupts disabled). + * + ****************************************************************************/ + +struct uip_udp_conn *uip_nextudpconn(struct uip_udp_conn *conn) +{ + if (!conn) + { + return (struct uip_udp_conn *)g_active_udp_connections.head; + } + else + { + return (struct uip_udp_conn *)conn->node.flink; + } +} + +/**************************************************************************** + * Name: uip_udpbind() + * + * Description: + * This function implements the UIP specific parts of the standard UDP + * bind() operation. + * + * Assumptions: + * This function is called from normal user level code. + * + ****************************************************************************/ + +#ifdef CONFIG_NET_IPv6 +int uip_udpbind(struct uip_udp_conn *conn, const struct sockaddr_in6 *addr) +#else +int uip_udpbind(struct uip_udp_conn *conn, const struct sockaddr_in *addr) +#endif +{ + int ret = -EADDRINUSE; + uip_lock_t flags; + + /* Is the user requesting to bind to any port? */ + + if (!addr->sin_port) + { + /* Yes.. Find an unused local port number */ + + conn->lport = htons(uip_selectport()); + ret = OK; + } + else + { + /* Interrupts must be disabled while access the UDP connection list */ + + flags = uip_lock(); + + /* Is any other UDP connection bound to this port? */ + + if (!uip_find_conn(addr->sin_port)) + { + /* No.. then bind the socket to the port */ + + conn->lport = addr->sin_port; + ret = OK; + } + + uip_unlock(flags); + } + return ret; +} + +/**************************************************************************** + * Name: uip_udpconnect() + * + * Description: + * This function sets up a new UDP connection. The function will + * automatically allocate an unused local port for the new + * connection. However, another port can be chosen by using the + * uip_udpbind() call, after the uip_udpconnect() function has been + * called. + * + * uip_udpenable() must be called before the connection is made active (i.e., + * is eligible for callbacks. + * + * addr The address of the remote host. + * + * Assumptions: + * This function is called user code. Interrupts may be enabled. + * + ****************************************************************************/ + +#ifdef CONFIG_NET_IPv6 +int uip_udpconnect(struct uip_udp_conn *conn, const struct sockaddr_in6 *addr) +#else +int uip_udpconnect(struct uip_udp_conn *conn, const struct sockaddr_in *addr) +#endif +{ + /* Has this address already been bound to a local port (lport)? */ + + if (!conn->lport) + { + /* No.. Find an unused local port number and bind it to the + * connection structure. + */ + + conn->lport = htons(uip_selectport()); + } + + /* Is there a remote port (rport) */ + + if (addr) + { + conn->rport = addr->sin_port; + uip_ipaddr_copy(conn->ripaddr, addr->sin_addr.s_addr); + } + else + { + conn->rport = 0; + uip_ipaddr_copy(conn->ripaddr, g_allzeroaddr); + } + + conn->ttl = UIP_TTL; + return OK; +} + +/**************************************************************************** + * Name: uip_udpenable() uip_udpdisable. + * + * Description: + * Enable/disable callbacks for the specified connection + * + * Assumptions: + * This function is called user code. Interrupts may be enabled. + * + ****************************************************************************/ + +void uip_udpenable(struct uip_udp_conn *conn) +{ + /* Add the connection structure to the active connectionlist. This list + * is modifiable from interrupt level, we we must disable interrupts to + * access it safely. + */ + + uip_lock_t flags = uip_lock(); + dq_addlast(&conn->node, &g_active_udp_connections); + uip_unlock(flags); +} + +void uip_udpdisable(struct uip_udp_conn *conn) +{ + /* Remove the connection structure from the active connectionlist. This list + * is modifiable from interrupt level, we we must disable interrupts to + * access it safely. + */ + + uip_lock_t flags = uip_lock(); + dq_rem(&conn->node, &g_active_udp_connections); + uip_unlock(flags); +} + +#endif /* CONFIG_NET && CONFIG_NET_UDP */ |