/* * Copyright (C) 2015 Freie Universität Berlin * * This file is subject to the terms and conditions of the GNU Lesser * General Public License v2.1. See the file LICENSE in the top level * directory for more details. */ /** * @defgroup net_gnrc_netif_hdr Generic network interface header * @ingroup net_gnrc_netif * @{ * * @file * @brief Generic network interface header * * @author Hauke Petersen * @author Martine Lenders */ #ifndef NET_GNRC_NETIF_HDR_H #define NET_GNRC_NETIF_HDR_H #include #include #include "net/gnrc/pkt.h" #include "net/gnrc/pktbuf.h" #ifdef __cplusplus extern "C" { #endif /** * @brief Maximum length of the l2 addresses of the generic interface header * in bytes. */ #define GNRC_NETIF_HDR_L2ADDR_MAX_LEN (8) /** * @brief Maximum length of the string representatiom of l2 addresses of the * generic interface header in bytes. */ #define GNRC_NETIF_HDR_L2ADDR_PRINT_LEN (GNRC_NETIF_HDR_L2ADDR_MAX_LEN * 3) /** * @{ * @name Flags for the gnrc_netif_hdr_t */ /** * @brief Send packet broadcast. * * @details Packets with this flag set must be send broadcast. * gnrc_netif_hdr_t::dst_l2addr_len and any appended destination * address must be ignored. * If the link layer does not support broadcast the packet must be * dropped silently. */ #define GNRC_NETIF_HDR_FLAGS_BROADCAST (0x80) /** * @brief Send packet multicast. * * @details Packets with this flag set must be send multicast. * gnrc_netif_hdr_t::dst_l2addr_len and any appended destination * address must be ignored. * The context for the multicast address must be derived from the * network layer destination address. * If the link layer does not support multicast it should interpret * this flag the same way it does @ref GNRC_NETIF_HDR_FLAGS_BROADCAST. */ #define GNRC_NETIF_HDR_FLAGS_MULTICAST (0x40) /** * @} */ /** * @brief Generic network interface header * * The link layer addresses included in this header are put in memory directly * following this struct. */ typedef struct { uint8_t src_l2addr_len; /**< length of l2 source address in byte */ uint8_t dst_l2addr_len; /**< length of l2 destination address in byte */ kernel_pid_t if_pid; /**< PID of network interface */ uint8_t flags; /**< flags as defined above */ uint8_t rssi; /**< rssi of received packet (optional) */ uint8_t lqi; /**< lqi of received packet (optional) */ } gnrc_netif_hdr_t; /** * @brief Initialize the given generic network interface header * * @param[in] hdr header to initialize * @param[in] src_l2addr_len link layer source address length * @param[in] dst_l2addr_len link layer destination address length */ static inline void gnrc_netif_hdr_init(gnrc_netif_hdr_t *hdr, uint8_t src_l2addr_len, uint8_t dst_l2addr_len) { hdr->src_l2addr_len = src_l2addr_len; hdr->dst_l2addr_len = dst_l2addr_len; hdr->if_pid = KERNEL_PID_UNDEF; hdr->rssi = 0; hdr->lqi = 0; hdr->flags = 0; } /** * @brief Get the size of the given generic network interface header * * @param[in] hdr header to get the size of * * @return the size of the given header, including link layer * addresses */ static inline size_t gnrc_netif_hdr_sizeof(gnrc_netif_hdr_t *hdr) { return sizeof(gnrc_netif_hdr_t) + hdr->src_l2addr_len + hdr->dst_l2addr_len; } /** * @brief Get the source address from the given header * * @param[in] hdr header to read from * * @return pointer to source address on success * @return NULL on error */ static inline uint8_t *gnrc_netif_hdr_get_src_addr(gnrc_netif_hdr_t *hdr) { return ((uint8_t *)(hdr + 1)); } /** * @brief Set the source address in the given header * * @param[in] hdr header to write to * @param[in] addr new source address * @param[in] addr_len *addr* length */ static inline void gnrc_netif_hdr_set_src_addr(gnrc_netif_hdr_t *hdr, uint8_t *addr, uint8_t addr_len) { if (addr_len != hdr->src_l2addr_len) { return; } memcpy(((uint8_t *)(hdr + 1)), addr, addr_len); } /** * @brief Get the destination address from the given header * * @param[in] hdr header to read from * * @return pointer to destination address on success * @return NULL on error */ static inline uint8_t *gnrc_netif_hdr_get_dst_addr(gnrc_netif_hdr_t *hdr) { return (((uint8_t *)(hdr + 1)) + hdr->src_l2addr_len); } /** * @brief Set the destination address in the given header * * @param[in] hdr header to write to * @param[in] addr new destination address * @param[in] addr_len *addr* length */ static inline void gnrc_netif_hdr_set_dst_addr(gnrc_netif_hdr_t *hdr, uint8_t *addr, uint8_t addr_len) { if (addr_len != hdr->dst_l2addr_len) { return; } memcpy(((uint8_t *)(hdr + 1)) + hdr->src_l2addr_len, addr, addr_len); } /** * @brief Builds a generic network interface header for sending and * adds it to the packet buffer. * * @param[in] src Source address for the header. Can be NULL if not * known or required. * @param[in] src_len Length of @p src. Can be 0 if not known or required. * @param[in] dst Destination address for the header. Can be NULL if not * known or required. * @param[in] dst_len Length of @p dst. Can be 0 if not known or required. * * @return The generic network layer header on success. * @return NULL on error. */ gnrc_pktsnip_t *gnrc_netif_hdr_build(uint8_t *src, uint8_t src_len, uint8_t *dst, uint8_t dst_len); /** * @brief Outputs a generic interface header to stdout. * * @param[in] hdr A generic interface header. */ void gnrc_netif_hdr_print(gnrc_netif_hdr_t *hdr); /** * @brief Fetch the netif header flags of a gnrc packet * * @param[in] pkt gnrc packet from whom to fetch * * @return netif header flags of @p pkt * @return 0, if no header is present */ uint8_t gnrc_netif_hdr_get_flag(gnrc_pktsnip_t* pkt); /** * @brief Extract the destination address out of a gnrc packet * * @param[in] pkt gnrc packet from whom to extract * @param[out] pointer_to_addr pointer to address will be stored here * * @return length of destination address * @return -ENOENT, if no netif header is presented in @p pkt or if no * destination address field presented in netif header. */ int gnrc_netif_hdr_get_dstaddr(gnrc_pktsnip_t* pkt, uint8_t** pointer_to_addr); /** * @brief Extract the source address out of a gnrc packet * * @param[in] pkt gnrc packet from whom to extract * @param[out] pointer_to_addr pointer to address will be stored here * * @return length of source address * @return -ENOENT, if no netif header is presented in @p pkt or if no * source address field presented in netif header. */ int gnrc_netif_hdr_get_srcaddr(gnrc_pktsnip_t* pkt, uint8_t** pointer_to_addr); #ifdef __cplusplus } #endif #endif /* NET_GNRC_NETIF_HDR_H */ /** @} */