/**************************************************************************** * net/arp/arp.h * * Copyright (C) 2014 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. Neither the name NuttX 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 COPYRIGHT HOLDERS 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 * COPYRIGHT OWNER 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. * ****************************************************************************/ #ifndef __NET_ARP_ARP_H #define __NET_ARP_ARP_H /* The Address Resolution Protocol ARP is used for mapping between IP * addresses and link level addresses such as the Ethernet MAC * addresses. ARP uses broadcast queries to ask for the link level * address of a known IP address and the host which is configured with * the IP address for which the query was meant, will respond with its * link level address. * * Note: This ARP implementation only supports Ethernet. */ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_DEBUG # undef CONFIG_NET_ARP_DUMP #endif #ifndef CONFIG_ARP_SEND_MAXTRIES # define CONFIG_ARP_SEND_MAXTRIES 5 #endif #ifndef CONFIG_ARP_SEND_DELAYMSEC # define CONFIG_ARP_SEND_DELAYMSEC 20 #endif /* ARP Definitions **********************************************************/ #define ARP_REQUEST 1 #define ARP_REPLY 2 #define ARP_HWTYPE_ETH 1 #define RASIZE 4 /* Size of ROUTER ALERT */ /* Allocate a new ARP data callback */ #define arp_callback_alloc(conn) devif_callback_alloc(&(conn)->list) #define arp_callback_free(conn,cb) devif_callback_free(cb, &(conn)->list) /**************************************************************************** * Public Types ****************************************************************************/ /* ARP header -- Size 28 bytes */ struct arp_hdr_s { uint16_t ah_hwtype; /* 16-bit Hardware type (Ethernet=0x001) */ uint16_t ah_protocol; /* 16-bit Protocol type (IP=0x0800) */ uint8_t ah_hwlen; /* 8-bit Hardware address size (6) */ uint8_t ah_protolen; /* 8-bit Procotol address size (4) */ uint16_t ah_opcode; /* 16-bit Operation */ uint8_t ah_shwaddr[6]; /* 48-bit Sender hardware address */ uint16_t ah_sipaddr[2]; /* 32-bit Sender IP adress */ uint8_t ah_dhwaddr[6]; /* 48-bit Target hardware address */ uint16_t ah_dipaddr[2]; /* 32-bit Target IP address */ }; /* IP header -- Size 20 or 24 bytes */ struct arp_iphdr_s { uint8_t eh_vhl; /* 8-bit Version (4) and header length (5 or 6) */ uint8_t eh_tos; /* 8-bit Type of service (e.g., 6=TCP) */ uint8_t eh_len[2]; /* 16-bit Total length */ uint8_t eh_ipid[2]; /* 16-bit Identification */ uint8_t eh_ipoffset[2]; /* 16-bit IP flags + fragment offset */ uint8_t eh_ttl; /* 8-bit Time to Live */ uint8_t eh_proto; /* 8-bit Protocol */ uint16_t eh_ipchksum; /* 16-bit Header checksum */ uint16_t eh_srcipaddr[2]; /* 32-bit Source IP address */ uint16_t eh_destipaddr[2]; /* 32-bit Destination IP address */ uint16_t eh_ipoption[2]; /* (optional) */ }; #ifdef CONFIG_NET_ARP_SEND /* This structure holds the state of the send operation until it can be * operated upon from the interrupt level. */ struct arp_send_s { FAR struct devif_callback_s *snd_cb; /* Reference to callback instance */ sem_t snd_sem; /* Used to wake up the waiting thread */ uint8_t snd_retries; /* Retry count */ volatile bool snd_sent; /* True: if request sent */ #ifdef CONFIG_NETDEV_MULTINIC uint8_t snd_ifname[IFNAMSIZ]; /* Interface name */ #endif in_addr_t snd_ipaddr; /* The IP address to be queried */ }; #endif #ifdef CONFIG_NET_ARP_SEND /* For symmetry with other protocols, a "connection" structure is * provided. But it is a singleton for the case of ARP packet transfers. */ struct arp_conn_s { FAR struct devif_callback_s *list; /* ARP callbacks */ }; #endif #ifdef CONFIG_NET_ARP_SEND /* Used to notify a thread waiting for a particular ARP response */ struct arp_notify_s { FAR struct arp_notify_s *nt_flink; /* Supports singly linked list */ in_addr_t nt_ipaddr; /* Waited for IP address in the mapping */ sem_t nt_sem; /* Will wake up the waiter */ int nt_result; /* The result of the wait */ }; #endif /**************************************************************************** * Public Data ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND /* This is the singleton "connection" structure */ extern struct arp_conn_s g_arp_conn; #endif /**************************************************************************** * Public Function Prototypes ****************************************************************************/ #ifdef CONFIG_NET_ARP /**************************************************************************** * Name: arp_reset * * Description: * Re-initialize the ARP table. * ****************************************************************************/ void arp_reset(void); /**************************************************************************** * Function: arp_timer_initialize * * Description: * Initialized the 10 second timer that is need by the ARP logic in order * to age ARP address associations * * Parameters: * None * * Returned Value: * None * * Assumptions: * Called once at system initialization time * ****************************************************************************/ void arp_timer_initialize(void); /**************************************************************************** * Name: arp_timer * * Description: * This function performs periodic timer processing in the ARP module * and should be called at regular intervals. The recommended interval * is 10 seconds between the calls. It is responsible for flushing old * entries in the ARP table. * ****************************************************************************/ void arp_timer(void); /**************************************************************************** * Name: arp_format * * Description: * Format an ARP packet. * * Input Parameters: * dev - Device structure * ipaddr - Target IP address (32-bit) * * Returned Value: * None * ****************************************************************************/ struct net_driver_s; /* Forward reference */ void arp_format(FAR struct net_driver_s *dev, in_addr_t ipaddr); /**************************************************************************** * Function: arp_send * * Description: * The arp_send() call may be to send an ARP request to resolve an IP * address. This function first checks if the IP address is already in * ARP table. If so, then it returns success immediately. * * If the requested IP address in not in the ARP table, then this function * will send an ARP request, delay, then check if the IP address is now in * the ARP table. It will repeat this sequence until either (1) the IP * address mapping is now in the ARP table, or (2) a configurable number * of timeouts occur without receiving the ARP replay. * * Parameters: * ipaddr The IP address to be queried. * * Returned Value: * Zero (OK) is returned on success and the IP address mapping can now be * found in the ARP table. On error a negated errno value is returned: * * -ETIMEDOUT: The number or retry counts has been exceed. * -EHOSTUNREACH: Could not find a route to the host * * Assumptions: * This function is called from the normal tasking context. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND int arp_send(in_addr_t ipaddr); #else # define arp_send(i) (0) #endif /**************************************************************************** * Function: arp_poll * * Description: * Poll all pending transfer for ARP requests to send. * * Assumptions: * This function is called from the MAC device driver indirectly through * devif_poll() and devif_timer() and may be called from the timer * interrupt/watchdog handler level. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND int arp_poll(FAR struct net_driver_s *dev, devif_poll_callback_t callback); #else # define arp_poll(d,c) (0) #endif /**************************************************************************** * Function: arp_wait_setup * * Description: * Called BEFORE an ARP request is sent. This function sets up the ARP * response timeout before the the ARP request is sent so that there is * no race condition when arp_wait() is called. * * Assumptions: * This function is called from ARP send and executes in the normal * tasking environment. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND void arp_wait_setup(in_addr_t ipaddr, FAR struct arp_notify_s *notify); #else # define arp_wait_setup(i,n) #endif /**************************************************************************** * Function: arp_wait_cancel * * Description: * Cancel any wait set after arp_wait_setup is called but before arm_wait() * is called (arp_wait() will automatically cancel the wait). * * Assumptions: * This function may execute in the interrupt context when called from * arp_wait(). * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND int arp_wait_cancel(FAR struct arp_notify_s *notify); #else # define arp_wait_cancel(n) (0) #endif /**************************************************************************** * Function: arp_wait * * Description: * Called each time that a ARP request is sent. This function will sleep * until either: (1) the matching ARP response is received, or (2) a * timeout occurs. * * Assumptions: * This function is called from ARP send and executes in the normal * tasking environment. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND struct timespec; int arp_wait(FAR struct arp_notify_s *notify, FAR struct timespec *timeout); #else # define arp_wait(n,t) (0) #endif /**************************************************************************** * Function: arp_notify * * Description: * Called each time that a ARP response is received in order to wake-up * any threads that may be waiting for this particular ARP response. * * Assumptions: * This function is called from the MAC device driver indirectly through * arp_arpin() and may be execute from the interrupt level. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND void arp_notify(in_addr_t ipaddr); #else # define arp_notify(i) #endif /**************************************************************************** * Name: arp_find * * Description: * Find the ARP entry corresponding to this IP address. * * Input parameters: * ipaddr - Refers to an IP address in network order * * Assumptions * Interrupts are disabled; Returned value will become unstable when * interrupts are re-enabled or if any other uIP APIs are called. * ****************************************************************************/ FAR struct arp_entry *arp_find(in_addr_t ipaddr); /**************************************************************************** * Name: arp_delete * * Description: * Remove an IP association from the ARP table * * Input parameters: * ipaddr - Refers to an IP address in network order * * Assumptions * Interrupts are disabled to assure exclusive access to the ARP table * (and because arp_find() is called). * ****************************************************************************/ #define arp_delete(ipaddr) \ { \ struct arp_entry *tabptr = arp_find(ipaddr); \ if (tabptr) \ { \ tabptr->at_ipaddr = 0; \ } \ } /**************************************************************************** * Name: arp_update * * Description: * Add the IP/HW address mapping to the ARP table -OR- change the IP * address of an existing association. * * Input parameters: * pipaddr - Refers to an IP address uint16_t[2] in network order * ethaddr - Refers to a HW address uint8_t[IFHWADDRLEN] * * Assumptions * Interrupts are disabled to assure exclusive access to the ARP table. * ****************************************************************************/ void arp_update(FAR uint16_t *pipaddr, FAR uint8_t *ethaddr); /**************************************************************************** * Name: arp_dump * * Description: * Dump the contents of an ARP packet to the SYSLOG device * * Input Parameters: * arp - A reference to the ARP header to be dumped. * * Returned Value: * None * ****************************************************************************/ #ifdef CONFIG_NET_ARP_DUMP void arp_dump(FAR struct arp_hdr_s *arp); #else # define arp_dump(arp) #endif #else /* CONFIG_NET_ARP */ /* If ARP is disabled, stub out all ARP interfaces */ # define arp_reset() # define arp_timer_initialize() # define arp_timer() # define arp_format(d,i); # define arp_send(i) (0) # define arp_poll(d,c) (0) # define arp_wait_setup(i,n) # define arp_wait_cancel(n) (0) # define arp_wait(n,t) (0) # define arp_notify(i) # define arp_find(i) (NULL) # define arp_delete(i) # define arp_update(i,m); # define arp_dump(arp) #endif /* CONFIG_NET_ARP */ #endif /* __NET_ARP_ARP_H */