/**************************************************************************** * net/arp/arp.h * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ #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 #include #include #include "devif/devif.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_DEBUG_FEATURES # 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(dev) devif_callback_alloc(dev, \ &(dev)->d_conncb, \ &(dev)->d_conncb_tail) #define arp_callback_free(dev,cb) devif_dev_callback_free(dev, cb) /* This is a helper pointer for accessing the contents of the IP header */ #define ARPBUF ((FAR struct arp_hdr_s *)IPBUF(0)) #define ARPIPBUF ((FAR struct arp_iphdr_s *)IPBUF(0)) /**************************************************************************** * 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 Protocol 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 address */ 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 network driver poll. */ typedef CODE void (*arp_send_finish_cb_t)(FAR struct net_driver_s *dev, int result); struct arp_send_s { FAR struct devif_callback_s *snd_cb; /* Reference to callback instance */ FAR arp_send_finish_cb_t finish_cb; /* Reference to send finish callback */ 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 */ uint8_t snd_ifname[IFNAMSIZ]; /* Interface name */ int16_t snd_result; /* The result of the send operation */ in_addr_t snd_ipaddr; /* The IP address to be queried */ }; #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 /* One entry in the ARP table (volatile!) */ struct arp_entry_s { in_addr_t at_ipaddr; /* IP address */ struct ether_addr at_ethaddr; /* Hardware address */ clock_t at_time; /* Time of last usage */ FAR struct net_driver_s *at_dev; /* The device driver structure */ }; /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Public Function Prototypes ****************************************************************************/ #ifdef CONFIG_NET_ARP /**************************************************************************** * 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); /**************************************************************************** * Name: arp_ipin * * Description: * The arp_ipin() function should be called by Ethernet device drivers * whenever an IP packet arrives from the network. The function will * check if the address is in the ARP cache, and if so the ARP cache entry * will be refreshed. * If no ARP cache entry was found, a new one is created. * * This function expects that an IP packet with an Ethernet header is * present in the d_buf buffer and that the length of the packet is in the * d_len field. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_IPIN void arp_ipin(FAR struct net_driver_s *dev); #else # define arp_ipin(dev) #endif /**************************************************************************** * Name: arp_out * * Description: * This function should be called before sending out an IPv4 packet. The * function checks the destination IPv4 address of the IPv4 packet to see * what Ethernet MAC address that should be used as a destination MAC * address on the Ethernet. * * If the destination IPv4 address is in the local network (determined * by logical ANDing of netmask and our IPv4 address), the function * checks the ARP cache to see if an entry for the destination IPv4 * address is found. If so, an Ethernet header is pre-pended at the * beginning of the packet and the function returns. * * If no ARP cache entry is found for the destination IIPv4P address, the * packet in the d_buf is replaced by an ARP request packet for the * IPv4 address. The IPv4 packet is dropped and it is assumed that the * higher level protocols (e.g., TCP) eventually will retransmit the * dropped packet. * * Upon return in either the case, a packet to be sent is present in the * d_buf buffer and the d_len field holds the length of the Ethernet * frame that should be transmitted. * ****************************************************************************/ void arp_out(FAR struct net_driver_s *dev); /**************************************************************************** * Name: arp_send * * Description: * The arp_send() call may be to send an ARP request to resolve an IPv4 * address. This function first checks if the IPv4 address is already in * the ARP table. If so, then it returns success immediately. * * If the requested IPv4 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. * * Input 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 /**************************************************************************** * Name: arp_send_async * * Description: * The arp_send_async() call may be to send an ARP request asyncly to * resolve an IPv4 address. * * Input Parameters: * ipaddr The IP address to be queried. * cb The callback when ARP send is finished, should not be NULL. * * Returned Value: * Zero (OK) is returned on success the arp been sent to the driver. * 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_async(in_addr_t ipaddr, arp_send_finish_cb_t cb); #endif /**************************************************************************** * Name: 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(). The network must be locked. * ****************************************************************************/ #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 /**************************************************************************** * Name: arp_wait_setup * * Description: * Called BEFORE an ARP request is sent. This function sets up the ARP * response timeout before 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 /**************************************************************************** * Name: 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 /**************************************************************************** * Name: 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 must execute with the network * un-locked. * ****************************************************************************/ #ifdef CONFIG_NET_ARP_SEND int arp_wait(FAR struct arp_notify_s *notify, unsigned int timeout); #else # define arp_wait(n,t) (0) #endif /**************************************************************************** * Name: 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_input() and will execute with the network locked. * ****************************************************************************/ #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 which may or may * not be in the ARP table (it may, instead, be a local network device). * * Input Parameters: * ipaddr - Refers to an IP address in network order * ethaddr - Location to return the corresponding Ethernet MAN address. * This address may be NULL. In that case, this function may be * used simply to determine if the Ethernet MAC address is * available. * dev - Device structure * * Assumptions * The network is locked to assure exclusive access to the ARP table. * ****************************************************************************/ struct ether_addr; /* Forward reference */ int arp_find(in_addr_t ipaddr, FAR uint8_t *ethaddr, FAR struct net_driver_s *dev); /**************************************************************************** * Name: arp_delete * * Description: * Remove an IP association from the ARP table * * Input Parameters: * ipaddr - Refers to an IP address in network order * dev - Device structure * * Assumptions * The network is locked to assure exclusive access to the ARP table. * ****************************************************************************/ int arp_delete(in_addr_t ipaddr, FAR struct net_driver_s *dev); /**************************************************************************** * Name: arp_cleanup * * Description: * Clear the ARP table on the network device * * Input Parameters: * dev - The device driver structure * * Assumptions * The network is locked to assure exclusive access to the ARP table. * ****************************************************************************/ void arp_cleanup(FAR struct net_driver_s *dev); /**************************************************************************** * 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: * dev - The device driver structure * ipaddr - The IP address as an inaddr_t * ethaddr - Refers to a HW address uint8_t[IFHWADDRLEN] * * Returned Value: * Zero (OK) if the ARP table entry was successfully modified. A negated * errno value is returned on any error. * * Assumptions * The network is locked to assure exclusive access to the ARP table * ****************************************************************************/ int arp_update(FAR struct net_driver_s *dev, in_addr_t ipaddr, FAR const uint8_t *ethaddr); /**************************************************************************** * Name: arp_hdr_update * * Description: * Add the IP/HW address mapping to the ARP table -OR- change the IP * address of an existing association. * * Input Parameters: * dev - The device driver structure * pipaddr - Refers to an IP address uint16_t[2] in network order * ethaddr - Refers to a HW address uint8_t[IFHWADDRLEN] * * Returned Value: * Zero (OK) if the ARP table entry was successfully modified. A negated * errno value is returned on any error. * * Assumptions * The network is locked to assure exclusive access to the ARP table * ****************************************************************************/ void arp_hdr_update(FAR struct net_driver_s *dev, FAR uint16_t *pipaddr, FAR const uint8_t *ethaddr); /**************************************************************************** * Name: arp_snapshot * * Description: * Take a snapshot of the current state of the ARP table. * * Input Parameters: * snapshot - Location to return the ARP table copy * nentries - The size of the user provided 'dest' in entries, each of * size sizeof(struct arp_entry_s) * * Returned Value: * On success, the number of entries actually copied is returned. Unused * entries are not returned. * * Assumptions * The network is locked to assure exclusive access to the ARP table * ****************************************************************************/ #ifdef CONFIG_NETLINK_ROUTE unsigned int arp_snapshot(FAR struct arpreq *snapshot, unsigned int nentries); #else # define arp_snapshot(s,n) (0) #endif /**************************************************************************** * 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 #ifdef CONFIG_NET_ARP_ACD /**************************************************************************** * Name: arp_acd_update * * Description: * interface of ARP Address Conflict Detection monitor * * Input Parameters: * dev - The device driver structure to use in the send operation * * Returned Value: * none * ****************************************************************************/ void arp_acd_update(FAR struct net_driver_s *dev); /**************************************************************************** * Name: arp_acd_set_addr * * Description: * setting address interface of ARP Address Conflict Detection * * Input Parameters: * dev - The device driver structure to use in the send operation * * Returned Value: * none * ****************************************************************************/ void arp_acd_set_addr(FAR struct net_driver_s *dev); /**************************************************************************** * Name: arp_acd_setup * * Description: * set up interface of ARP Address Conflict Detection * * Input Parameters: * dev - The device driver structure to use in the send operation * * Returned Value: * none * ****************************************************************************/ void arp_acd_setup(FAR struct net_driver_s *dev); #endif /* CONFIG_NET_ARP_ACD */ #else /* CONFIG_NET_ARP */ /* If ARP is disabled, stub out all ARP interfaces */ # define arp_format(d,i); # define arp_ipin(dev) # define arp_out(dev) # 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,e,d) (-ENOSYS) # define arp_delete(i,d) (-ENOSYS) # define arp_cleanup(d) # define arp_update(d,i,m); # define arp_hdr_update(d,i,m); # define arp_snapshot(s,n) (0) # define arp_dump(arp) #endif /* CONFIG_NET_ARP */ #endif /* __NET_ARP_ARP_H */