diff options
Diffstat (limited to 'nuttx/net/uip/uip-fw.c')
| -rw-r--r-- | nuttx/net/uip/uip-fw.c | 508 |
1 files changed, 0 insertions, 508 deletions
diff --git a/nuttx/net/uip/uip-fw.c b/nuttx/net/uip/uip-fw.c deleted file mode 100644 index fa9b5fc4e..000000000 --- a/nuttx/net/uip/uip-fw.c +++ /dev/null @@ -1,508 +0,0 @@ -/* uip-fw.c - * uIP packet forwarding. - * Author: Adam Dunkels <adam@sics.se> - * - * This file implements a number of simple functions which do packet - * forwarding over multiple network interfaces with uIP. - * - * Copyright (c) 2004, Swedish Institute of Computer Science. - * 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. Neither the name of the Institute nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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. - */ - -#include <nuttx/config.h> -#include <debug.h> -#include <net/uip/uip.h> -#include <net/uip/uip-arch.h> - -#include "uip-fw.h" - -#include <string.h> /* for memcpy() */ - -/* The list of registered network interfaces. */ - -static struct uip_fw_netif *netifs = NULL; - -/* A pointer to the default network interface. */ - -static struct uip_fw_netif *defaultnetif = NULL; - -struct tcpip_hdr -{ - /* IP header */ - - uint8 vhl; - uint8 tos; - uint16 len; - uint16 ipid; - uint16 ipoffset; - uint8 ttl; - uint8 proto; - uint16 ipchksum; - in_addr_t srcipaddr; - in_addr_t destipaddr; - - /* TCP header */ - - uint16 srcport; - uint16 destport; - uint8 seqno[4]; - uint8 ackno[4]; - uint8 tcpoffset; - uint8 flags; - uint8 wnd[2]; - uint16 tcpchksum; - uint8 urgp[2]; - uint8 optdata[4]; -}; - -struct icmpip_hdr -{ - /* IP header */ - - uint8 vhl; - uint8 tos; - uint8 len[2]; - uint8 ipid[2]; - uint8 ipoffset[2]; - uint8 ttl; - uint8 proto; - uint16 ipchksum; - in_addr_t srcipaddr; - in_addr_t destipaddr; - - /* ICMP (echo) header */ - - uint8 type, icode; - uint16 icmpchksum; - uint16 id, seqno; - uint8 payload[1]; -}; - -/* ICMP ECHO. */ - -#define ICMP_ECHO 8 - -/* ICMP TIME-EXCEEDED. */ - -#define ICMP_TE 11 - -/* Pointer to the TCP/IP headers of the packet in the d_buf buffer. */ - -#define BUF ((struct tcpip_hdr *)&dev->d_buf[UIP_LLH_LEN]) - -/* Pointer to the ICMP/IP headers of the packet in the d_buf buffer. */ - -#define ICMPBUF ((struct icmpip_hdr *)&dev->d_buf[UIP_LLH_LEN]) - -/* Certain fields of an IP packet that are used for identifying - * duplicate packets. - */ - -struct fwcache_entry -{ - uint16 timer; - in_addr_t srcipaddr; - in_addr_t destipaddr; - uint16 ipid; - uint8 proto; - uint8 unused; - -#if notdef - uint16 payload[2]; -#endif - -#if UIP_REASSEMBLY > 0 - uint16 len, offset; -#endif -}; - -/* The number of packets to remember when looking for duplicates. */ -#ifdef CONFIG_NET_FWCACHE_SIZE -# define FWCACHE_SIZE CONFIG_NET_FWCACHE_SIZE -#else -# define FWCACHE_SIZE 2 -#endif - -/* A cache of packet header fields which are used for - * identifying duplicate packets. - */ - -static struct fwcache_entry fwcache[FWCACHE_SIZE]; - -/* The time that a packet cache is active. */ -#define FW_TIME 20 - -/* Initialize the uIP packet forwarding module. */ - -void uip_fw_init(void) -{ - struct uip_fw_netif *t; - defaultnetif = NULL; - while(netifs != NULL) - { - t = netifs; - netifs = netifs->next; - t->next = NULL; - } -} - -/* Send out an ICMP TIME-EXCEEDED message. - * - * This function replaces the packet in the d_buf buffer with the - * ICMP packet. - */ - -static void time_exceeded(struct uip_driver_s *dev) -{ - in_addr_t tmp_addr; - - /* We don't send out ICMP errors for ICMP messages. */ - - if (ICMPBUF->proto == UIP_PROTO_ICMP) - { - dev->d_len = 0; - return; - } - - /* Copy fields from packet header into payload of this ICMP packet. */ - - memcpy(&(ICMPBUF->payload[0]), ICMPBUF, 28); - - /* Set the ICMP type and code. */ - - ICMPBUF->type = ICMP_TE; - ICMPBUF->icode = 0; - - /* Calculate the ICMP checksum. */ - - ICMPBUF->icmpchksum = 0; - ICMPBUF->icmpchksum = ~uip_chksum((uint16 *)&(ICMPBUF->type), 36); - - /* Set the IP destination address to be the source address of the - * original packet. - */ - - tmp_addr = BUF->destipaddr; - BUF->destipaddr = BUF->srcipaddr; - BUF->srcipaddr = tmp_addr; - - /* Set our IP address as the source address. */ - - BUF->srcipaddr = dev->d_ipaddr; - - /* The size of the ICMP time exceeded packet is 36 + the size of the - * IP header (20) = 56. - */ - - dev->d_len = 56; - ICMPBUF->len[0] = 0; - ICMPBUF->len[1] = dev->d_len; - - /* Fill in the other fields in the IP header. */ - - ICMPBUF->vhl = 0x45; - ICMPBUF->tos = 0; - ICMPBUF->ipoffset[0] = ICMPBUF->ipoffset[1] = 0; - ICMPBUF->ttl = UIP_TTL; - ICMPBUF->proto = UIP_PROTO_ICMP; - - /* Calculate IP checksum. */ - - ICMPBUF->ipchksum = 0; - ICMPBUF->ipchksum = ~(uip_ipchksum(dev)); -} - -/* Register a packet in the forwarding cache so that it won't be - * forwarded again. - */ - -static void fwcache_register(struct uip_driver_s *dev) -{ - struct fwcache_entry *fw; - int i, oldest; - - oldest = FW_TIME; - fw = NULL; - - /* Find the oldest entry in the cache. */ - - for (i = 0; i < FWCACHE_SIZE; ++i) - { - if (fwcache[i].timer == 0) - { - fw = &fwcache[i]; - break; - } - else if (fwcache[i].timer <= oldest) - { - fw = &fwcache[i]; - oldest = fwcache[i].timer; - } - } - - fw->timer = FW_TIME; - fw->ipid = BUF->ipid; - fw->srcipaddr = BUF->srcipaddr; - fw->destipaddr = BUF->destipaddr; - fw->proto = BUF->proto; -#if notdef - fw->payload[0] = BUF->srcport; - fw->payload[1] = BUF->destport; -#endif -#if UIP_REASSEMBLY > 0 - fw->len = BUF->len; - fw->offset = BUF->ipoffset; -#endif -} - -/* Find a network interface for the IP packet in d_buf. */ - -static struct uip_fw_netif *find_netif (struct uip_driver_s *dev) -{ - struct uip_fw_netif *netif; - - /* Walk through every network interface to check for a match. */ - - for (netif = netifs; netif != NULL; netif = netif->next) - { - if (uip_ipaddr_maskcmp(BUF->destipaddr, netif->ipaddr, netif->netmask)) - { - /* If there was a match, we break the loop. */ - - return netif; - } - } - - /* If no matching netif was found, we use default netif. */ - - return defaultnetif; -} - -/* Output an IP packet on the correct network interface. - * - * The IP packet should be present in the d_buf buffer and its - * length in the d_len field. - * - * Return: UIP_FW_ZEROLEN Indicates that a zero-length packet - * transmission was attempted and that no packet was sent. - * - * Return: UIP_FW_NOROUTE No suitable network interface could be found - * for the outbound packet, and the packet was not sent. - * - * Return: The return value from the actual network interface output - * function is passed unmodified as a return value. - */ - -uint8 uip_fw_output(struct uip_driver_s *dev) -{ - struct uip_fw_netif *netif; - - if (dev->d_len == 0) - { - return UIP_FW_ZEROLEN; - } - - fwcache_register(dev); - -#ifdef CONFIG_NET_BROADCAST - /* Link local broadcasts go out on all interfaces. */ - - if (/*BUF->proto == UIP_PROTO_UDP &&*/ - BUF->destipaddr[0] == 0xffff && - BUF->destipaddr[1] == 0xffff) - { - if (defaultnetif != NULL) - { - defaultnetif->output(); - } - for (netif = netifs; netif != NULL; netif = netif->next) - { - netif->output(); - } - return UIP_FW_OK; - } -#endif - - netif = find_netif (dev); - dbg("netif: %p output: %p len: %d\n", netif, netif->output, dev->d_len); - - if (netif == NULL) - { - return UIP_FW_NOROUTE; - } - - /* If we now have found a suitable network interface, we call its - * output function to send out the packet. - */ - - return netif->output(); -} - -/* Forward an IP packet in the d_buf buffer. - * - * Return: UIP_FW_FORWARDED if the packet was forwarded, UIP_FW_LOCAL if - * the packet should be processed locally. - */ - -uint8 uip_fw_forward(struct uip_driver_s *dev) -{ - struct fwcache_entry *fw; - - /* First check if the packet is destined for ourselves and return 0 - * to indicate that the packet should be processed locally. - */ - - if (BUF->destipaddr == dev->d_ipaddr) - { - return UIP_FW_LOCAL; - } - - /* If we use ping IP address configuration, and our IP address is - * not yet configured, we should intercept all ICMP echo packets. - */ - -#ifdef CONFIG_NET_PINGADDRCONF - if (dev->d_ipaddr == 0 && BUF->proto == UIP_PROTO_ICMP && ICMPBUF->type == ICMP_ECHO) - { - return UIP_FW_LOCAL; - } -#endif - - /* Check if the packet is in the forwarding cache already, and if so - we drop it. */ - - for (fw = fwcache; fw < &fwcache[FWCACHE_SIZE]; ++fw) - { - if (fw->timer != 0 && -#if UIP_REASSEMBLY > 0 - fw->len == BUF->len && - fw->offset == BUF->ipoffset && -#endif - fw->ipid == BUF->ipid && - fw->srcipaddr == BUF->srcipaddr && - fw->destipaddr == BUF->destipaddr && -#if notdef - fw->payload[0] == BUF->srcport && - fw->payload[1] == BUF->destport && -#endif - fw->proto == BUF->proto) - { - /* Drop packet. */ - return UIP_FW_FORWARDED; - } - } - - /* If the TTL reaches zero we produce an ICMP time exceeded message - * in the d_buf buffer and forward that packet back to the sender - * of the packet. - */ - - if (BUF->ttl <= 1) - { - /* No time exceeded for broadcasts and multicasts! */ - - if (BUF->destipaddr == 0xffffffff) - { - return UIP_FW_LOCAL; - } - time_exceeded(dev); - } - - /* Decrement the TTL (time-to-live) value in the IP header */ - - BUF->ttl = BUF->ttl - 1; - - /* Update the IP checksum. */ - - if (BUF->ipchksum >= HTONS(0xffff - 0x0100)) - { - BUF->ipchksum = BUF->ipchksum + HTONS(0x0100) + 1; - } - else - { - BUF->ipchksum = BUF->ipchksum + HTONS(0x0100); - } - - if (dev->d_len > 0) - { - dev->d_appdata = &dev->d_buf[UIP_LLH_LEN + UIP_TCPIP_HLEN]; - uip_fw_output(dev); - } - -#ifdef CONFIG_NET_BROADCAST - if (BUF->destipaddr[0] == 0xffff && BUF->destipaddr[1] == 0xffff) - { - return UIP_FW_LOCAL; - } -#endif - - /* Return non-zero to indicate that the packet was forwarded and that no - * other processing should be made. - */ - - return UIP_FW_FORWARDED; -} - -/* Register a network interface with the forwarding module. - * - * netif A pointer to the network interface that is to be - * registered. - */ - -void uip_fw_register(struct uip_fw_netif *netif) -{ - netif->next = netifs; - netifs = netif; -} - -/* Register a default network interface. - * - * All packets that don't go out on any of the other interfaces will - * be routed to the default interface. - * - * netif A pointer to the network interface that is to be - * registered. - */ - -void uip_fw_default(struct uip_fw_netif *netif) -{ - defaultnetif = netif; -} - -/* Perform periodic processing. */ - -void uip_fw_periodic(void) -{ - struct fwcache_entry *fw; - for (fw = fwcache; fw < &fwcache[FWCACHE_SIZE]; ++fw) - { - if (fw->timer > 0) - { - --fw->timer; - } - } -} |