From f249c0c2a04206cc2d7df02cb363ac54d65e9253 Mon Sep 17 00:00:00 2001 From: Martine Lenders Date: Tue, 20 Jun 2017 10:23:20 +0200 Subject: [PATCH] gnrc_ipv6_nib: provide internal implementation for off-link entries --- sys/include/net/gnrc/ipv6/nib/conf.h | 10 ++ .../network_layer/ipv6/nib/_nib-internal.c | 115 ++++++++++++++++-- .../network_layer/ipv6/nib/_nib-internal.h | 86 +++++++------ 3 files changed, 160 insertions(+), 51 deletions(-) diff --git a/sys/include/net/gnrc/ipv6/nib/conf.h b/sys/include/net/gnrc/ipv6/nib/conf.h index 3d3faa7082..c0c298505e 100644 --- a/sys/include/net/gnrc/ipv6/nib/conf.h +++ b/sys/include/net/gnrc/ipv6/nib/conf.h @@ -184,6 +184,16 @@ extern "C" { #define GNRC_IPV6_NIB_NUMOF (4) #endif +/** + * @brief Number of off-link entries in NIB + * + * @attention This number is equal to the maximum number of forwarding table + * and prefix list entries in NIB + */ +#ifndef GNRC_IPV6_NIB_OFFL_NUMOF +#define GNRC_IPV6_NIB_OFFL_NUMOF (8) +#endif + #ifdef __cplusplus } #endif diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c index f366d5ec7c..6f2a665f3d 100644 --- a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c +++ b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c @@ -33,6 +33,7 @@ static _nib_dr_entry_t *_prime_def_router = NULL; static clist_node_t _next_removable = { NULL }; static _nib_onl_entry_t _nodes[GNRC_IPV6_NIB_NUMOF]; +static _nib_offl_entry_t _dsts[GNRC_IPV6_NIB_OFFL_NUMOF]; static _nib_dr_entry_t _def_routers[GNRC_IPV6_NIB_DEFAULT_ROUTER_NUMOF]; static _nib_iface_t _nis[GNRC_NETIF_NUMOF]; @@ -53,33 +54,41 @@ void _nib_init(void) _next_removable.next = NULL; memset(_nodes, 0, sizeof(_nodes)); memset(_def_routers, 0, sizeof(_def_routers)); + memset(_dsts, 0, sizeof(_dsts)); memset(_nis, 0, sizeof(_nis)); #endif /* TODO: load ABR information from persistent memory */ } +static inline bool _addr_equals(const ipv6_addr_t *addr, + const _nib_onl_entry_t *node) +{ + return (addr == NULL) || ipv6_addr_is_unspecified(&node->ipv6) || + (ipv6_addr_equal(addr, &node->ipv6)); +} + _nib_onl_entry_t *_nib_onl_alloc(const ipv6_addr_t *addr, unsigned iface) { _nib_onl_entry_t *node = NULL; - assert(addr != NULL); DEBUG("nib: Allocating on-link node entry (addr = %s, iface = %u)\n", - ipv6_addr_to_str(addr_str, addr, sizeof(addr_str)), iface); + (addr == NULL) ? "NULL" : ipv6_addr_to_str(addr_str, addr, + sizeof(addr_str)), iface); for (unsigned i = 0; i < GNRC_IPV6_NIB_NUMOF; i++) { _nib_onl_entry_t *tmp = &_nodes[i]; - if ((_nib_onl_get_if(tmp) == iface) && - (ipv6_addr_equal(addr, &tmp->ipv6))) { + if ((_nib_onl_get_if(tmp) == iface) && _addr_equals(addr, tmp)) { /* exact match */ DEBUG(" %p is an exact match\n", (void *)tmp); - return tmp; + node = tmp; + break; } if ((node == NULL) && (tmp->mode == _EMPTY)) { + DEBUG(" using %p\n", (void *)node); node = tmp; } } if (node != NULL) { - DEBUG(" using %p\n", (void *)node); _override_node(addr, iface, node); } #if ENABLE_DEBUG @@ -141,6 +150,7 @@ static inline _nib_onl_entry_t *_cache_out_onl_entry(const ipv6_addr_t *addr, _nib_onl_entry_t *_nib_nc_add(const ipv6_addr_t *addr, unsigned iface, uint16_t cstate) { + assert(addr != NULL); cstate &= GNRC_IPV6_NIB_NC_INFO_NUD_STATE_MASK; assert(cstate != GNRC_IPV6_NIB_NC_INFO_NUD_STATE_DELAY); assert(cstate != GNRC_IPV6_NIB_NC_INFO_NUD_STATE_PROBE); @@ -341,6 +351,95 @@ _nib_dr_entry_t *_nib_drl_get_dr(void) return _prime_def_router; } +_nib_offl_entry_t *_nib_offl_alloc(const ipv6_addr_t *next_hop, unsigned iface, + const ipv6_addr_t *pfx, unsigned pfx_len) +{ + _nib_offl_entry_t *dst = NULL; + + assert((pfx != NULL) && (!ipv6_addr_is_unspecified(pfx)) && + (pfx_len > 0) && (pfx_len <= 128)); + DEBUG("nib: Allocating off-link-entry entry " + "(next_hop = %s, iface = %u, ", + (next_hop == NULL) ? "NULL" : ipv6_addr_to_str(addr_str, next_hop, + sizeof(addr_str)), + iface); + DEBUG("pfx = %s/%u)\n", ipv6_addr_to_str(addr_str, pfx, + sizeof(addr_str)), pfx_len); + for (unsigned i = 0; i < GNRC_IPV6_NIB_OFFL_NUMOF; i++) { + _nib_offl_entry_t *tmp = &_dsts[i]; + _nib_onl_entry_t *tmp_node = tmp->next_hop; + + if ((tmp->pfx_len == pfx_len) && /* prefix length matches and */ + (tmp_node != NULL) && /* there is a next hop that */ + (_nib_onl_get_if(tmp_node) == iface) && /* has a matching interface and */ + _addr_equals(next_hop, tmp_node) && /* equal address to next_hop, also */ + (ipv6_addr_match_prefix(&tmp->pfx, pfx) >= pfx_len)) { /* the prefix matches */ + /* exact match (or next hop address was previously unset) */ + DEBUG(" %p is an exact match\n", (void *)tmp); + if (next_hop != NULL) { + memcpy(&tmp_node->ipv6, next_hop, sizeof(tmp_node->ipv6)); + } + tmp->next_hop->mode |= _DST; + return tmp; + } + if ((dst == NULL) && (tmp_node == NULL)) { + dst = tmp; + } + } + if (dst != NULL) { + DEBUG(" using %p\n", (void *)dst); + dst->next_hop = _nib_onl_alloc(next_hop, iface); + + if (dst->next_hop == NULL) { + memset(dst, 0, sizeof(_nib_offl_entry_t)); + return NULL; + } + _override_node(next_hop, iface, dst->next_hop); + dst->next_hop->mode |= _DST; + ipv6_addr_init_prefix(&dst->pfx, pfx, pfx_len); + dst->pfx_len = pfx_len; + } + return dst; +} + +static inline bool _in_dsts(const _nib_offl_entry_t *dst) +{ + return (dst < (_dsts + GNRC_IPV6_NIB_OFFL_NUMOF)); +} + +void _nib_offl_clear(_nib_offl_entry_t *dst) +{ + if (dst->next_hop != NULL) { + _nib_offl_entry_t *ptr; + for (ptr = _dsts; _in_dsts(ptr); ptr++) { + /* there is another dst pointing to next-hop => only remove dst */ + if ((dst != ptr) && (dst->next_hop == ptr->next_hop)) { + break; + } + } + /* we iterated and found no further dst pointing to next-hop */ + if (!_in_dsts(ptr)) { + dst->next_hop->mode &= ~(_DST); + _nib_onl_clear(dst->next_hop); + } + memset(dst, 0, sizeof(_nib_offl_entry_t)); + } +} + +_nib_offl_entry_t *_nib_offl_iter(const _nib_offl_entry_t *last) +{ + for (const _nib_offl_entry_t *dst = (last) ? (last + 1) : _dsts; + _in_dsts(dst); + dst++) { + if (dst->mode != _EMPTY) { + /* const modifier provided to assure internal consistency. + * Can now be discarded. */ + return (_nib_offl_entry_t *)dst; + } + } + return NULL; +} + _nib_iface_t *_nib_iface_get(unsigned iface) { _nib_iface_t *ni = NULL; @@ -367,7 +466,9 @@ static void _override_node(const ipv6_addr_t *addr, unsigned iface, _nib_onl_entry_t *node) { _nib_onl_clear(node); - memcpy(&node->ipv6, addr, sizeof(node->ipv6)); + if (addr != NULL) { + memcpy(&node->ipv6, addr, sizeof(node->ipv6)); + } _nib_onl_set_if(node, iface); } diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h index 980565cc14..25d1953af6 100644 --- a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h +++ b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h @@ -19,6 +19,7 @@ #ifndef PRIV_NIB_INTERNAL_H #define PRIV_NIB_INTERNAL_H +#include #include #include @@ -48,6 +49,8 @@ extern "C" { #define _DRL (0x08) /**< default router list */ #define _FT (0x10) /**< forwarding table */ #define _DAD (0x20) /**< 6LoWPAN duplicate address detection table */ +#define _DST (0x40) /**< there is @ref _nib_offl_entry_t pointing + to this @ref _nib_onl_entry_t */ /** @} */ /** @@ -148,6 +151,8 @@ typedef struct { ipv6_addr_t pfx; /**< prefix to the destination */ unsigned pfx_len; /**< prefix-length in bits of * _nib_onl_entry_t::pfx */ + uint8_t mode; /**< [mode](@ref net_gnrc_ipv6_nib_mode) of the + * off-link entry */ } _nib_offl_entry_t; /** @@ -232,10 +237,8 @@ static inline void _nib_onl_set_if(_nib_onl_entry_t *node, unsigned iface) /** * @brief Creates or gets an existing on-link entry by address * - * @pre `(addr != NULL)`. - * - * @param[in] addr An IPv6 address. May not be NULL. - * *May also be a global address!* + * @param[in] addr An IPv6 address. May be NULL (to be pointed to by a prefix + * list entry). *May also be a global address!* * @param[in] iface The interface to the node. * * @return A new or existing on-link entry with _nib_onl_entry_t::ipv6 set to @@ -286,7 +289,6 @@ _nib_onl_entry_t *_nib_onl_get(const ipv6_addr_t *addr, unsigned iface); /** * @brief Creates or gets an existing node from the neighbor cache by address * - * @pre `(addr != NULL)` * @pre `((cstate & GNRC_IPV6_NIB_NC_INFO_NUD_STATE_MASK) != * GNRC_IPV6_NIB_NC_INFO_NUD_STATE_DELAY)` * @pre `((cstate & GNRC_IPV6_NIB_NC_INFO_NUD_STATE_MASK) != @@ -294,7 +296,8 @@ _nib_onl_entry_t *_nib_onl_get(const ipv6_addr_t *addr, unsigned iface); * @pre `((cstate & GNRC_IPV6_NIB_NC_INFO_NUD_STATE_MASK) != * GNRC_IPV6_NIB_NC_INFO_NUD_STATE_REACHABLE)` * - * @param[in] addr The address of a node. May not be NULL. + * @param[in] addr The address of a node. May be NULL for prefix list + * entries. * @param[in] iface The interface to the node. * @param[in] cstate Creation state. State of the entry *if* the entry is * newly created. @@ -333,6 +336,7 @@ void _nib_nc_set_reachable(_nib_onl_entry_t *node); */ static inline _nib_onl_entry_t *_nib_dad_add(const ipv6_addr_t *addr) { + assert(addr != NULL); _nib_onl_entry_t *node = _nib_onl_alloc(addr, 0); if (node != NULL) { @@ -412,11 +416,10 @@ _nib_dr_entry_t *_nib_drl_get_dr(void); /** * @brief Creates or gets an existing off-link entry by next hop and prefix * - * @pre `(next_hop != NULL)` * @pre `(pfx != NULL) && (pfx != "::") && (pfx_len != 0) && (pfx_len <= 128)` * - * @param[in] next_hop An IPv6 address to next hop. May not be NULL. - * *May also be a global address!* + * @param[in] next_hop An IPv6 address to next hop. May be NULL (for prefix + * list). *May also be a global address!* * @param[in] iface The interface to @p next_hop. * @param[in] pfx The IPv6 prefix or address of the destination. * May not be NULL or unspecified address. Use @@ -427,15 +430,15 @@ _nib_dr_entry_t *_nib_drl_get_dr(void); * @p pfx. * @return NULL, if no space is left. */ -_nib_offl_entry_t *_nib_dst_alloc(const ipv6_addr_t *next_hop, unsigned iface, - const ipv6_addr_t *pfx, unsigned pfx_len); +_nib_offl_entry_t *_nib_offl_alloc(const ipv6_addr_t *next_hop, unsigned iface, + const ipv6_addr_t *pfx, unsigned pfx_len); /** * @brief Clears out a NIB entry (off-link version) * * @param[in,out] dst An entry. */ -void _nib_dst_clear(_nib_offl_entry_t *dst); +void _nib_offl_clear(_nib_offl_entry_t *dst); /** * @brief Iterates over off-link entries @@ -444,16 +447,15 @@ void _nib_dst_clear(_nib_offl_entry_t *dst); * * @return entry after @p last. */ -_nib_offl_entry_t *_nib_dst_iter(const _nib_offl_entry_t *last); +_nib_offl_entry_t *_nib_offl_iter(const _nib_offl_entry_t *last); /** * @brief Helper function for view-level add-functions below * - * @pre `(next_hop != NULL)` * @pre `(pfx != NULL) && (pfx != "::") && (pfx_len != 0) && (pfx_len <= 128)` * - * @param[in] next_hop Next hop to the destination. May not be NULL. - * *May also be a global address!* + * @param[in] next_hop An IPv6 address to next hop. May be NULL (for prefix + * list). *May also be a global address!* * @param[in] iface The interface to the destination. * @param[in] pfx The IPv6 prefix or address of the destination. * May not be NULL or unspecified address. Use @@ -461,19 +463,19 @@ _nib_offl_entry_t *_nib_dst_iter(const _nib_offl_entry_t *last); * @param[in] pfx_len The length in bits of @p pfx in bits. * @param[in] mode [NIB-mode](_nib_onl_entry_t::mode). * - * @return A new or existing off-link entry with _nib_dr_entry_t::pfx set to + * @return A new or existing off-link entry with _nib_offl_entry_t::pfx set to * @p pfx. * @return NULL, if no space is left. */ -static inline _nib_offl_entry_t *_nib_dst_add(const ipv6_addr_t *next_hop, - unsigned iface, - const ipv6_addr_t *pfx, - unsigned pfx_len, uint8_t mode) +static inline _nib_offl_entry_t *_nib_offl_add(const ipv6_addr_t *next_hop, + unsigned iface, + const ipv6_addr_t *pfx, + unsigned pfx_len, uint8_t mode) { - _nib_offl_entry_t *nib_offl = _nib_dst_alloc(next_hop, iface, pfx, pfx_len); + _nib_offl_entry_t *nib_offl = _nib_offl_alloc(next_hop, iface, pfx, pfx_len); if (nib_offl != NULL) { - nib_offl->next_hop->mode |= (mode); + nib_offl->mode |= mode; } return nib_offl; } @@ -483,17 +485,13 @@ static inline _nib_offl_entry_t *_nib_dst_add(const ipv6_addr_t *next_hop, * * @param[in,out] nib_offl An entry. */ -static inline void _nib_dst_remove(_nib_offl_entry_t *nib_offl, uint8_t mode) +static inline void _nib_offl_remove(_nib_offl_entry_t *nib_offl, uint8_t mode) { - _nib_onl_entry_t *node = nib_offl->next_hop; - - if (node != NULL) { - node->mode &= ~mode; - } - _nib_dst_clear(nib_offl); + nib_offl->mode &= ~mode; + _nib_offl_clear(nib_offl); } -#if defined(GNRC_IPV6_NIB_CONF_DC) || DOXYGEN +#if GNRC_IPV6_NIB_CONF_DC || DOXYGEN /** * @brief Creates or gets an existing destination cache entry by its addresses * @@ -506,16 +504,16 @@ static inline void _nib_dst_remove(_nib_offl_entry_t *nib_offl, uint8_t mode) * * @note Only available if @ref GNRC_IPV6_NIB_CONF_DC. * - * @return A new or existing destination cache entry with - * _nib_onl_entry_t::ipv6 of _nib_dr_entry_t::next_hop set to - * @p next_hop. + * @return A new or existing off-link entry with _nib_offl_entry_t::pfx set to + * @p pfx. * @return NULL, if no space is left. */ static inline _nib_offl_entry_t *_nib_dc_add(const ipv6_addr_t *next_hop, unsigned iface, const ipv6_addr_t *dst) { - return _nib_dst_add(next_hop, iface, dst, IPV6_ADDR_BIT_LEN, _DC); + assert((next_hop != NULL) && (dst != NULL)); + return _nib_offl_add(next_hop, iface, dst, IPV6_ADDR_BIT_LEN, _DC); } /** @@ -529,7 +527,7 @@ static inline _nib_offl_entry_t *_nib_dc_add(const ipv6_addr_t *next_hop, */ static inline void _nib_dc_remove(_nib_offl_entry_t *nib_offl) { - _nib_dst_remove(nib_offl, _DC); + _nib_offl_remove(nib_offl, _DC); } #endif /* GNRC_IPV6_NIB_CONF_DC */ @@ -545,7 +543,7 @@ static inline void _nib_dc_remove(_nib_offl_entry_t *nib_offl) * @ref _nib_drl_add() for default route destinations. * @param[in] pfx_len The length in bits of @p pfx in bits. * - * @return A new or existing prefix list entry with _nib_dr_entry_t::pfx set to + * @return A new or existing off-link entry with _nib_offl_entry_t::pfx set to * @p pfx. * @return NULL, if no space is left. */ @@ -553,7 +551,7 @@ static inline _nib_offl_entry_t *_nib_pl_add(unsigned iface, const ipv6_addr_t *pfx, unsigned pfx_len) { - return _nib_dst_add(NULL, iface, pfx, pfx_len, _PL); + return _nib_offl_add(NULL, iface, pfx, pfx_len, _PL); } /** @@ -565,10 +563,10 @@ static inline _nib_offl_entry_t *_nib_pl_add(unsigned iface, */ static inline void _nib_pl_remove(_nib_offl_entry_t *nib_offl) { - _nib_dst_remove(nib_offl, _PL); + _nib_offl_remove(nib_offl, _PL); } -#if defined(GNRC_IPV6_NIB_CONF_ROUTER) || DOXYGEN +#if GNRC_IPV6_NIB_CONF_ROUTER || DOXYGEN /** * @brief Creates or gets an existing forwarding table entry by its prefix * @@ -585,8 +583,8 @@ static inline void _nib_pl_remove(_nib_offl_entry_t *nib_offl) * * @note Only available if @ref GNRC_IPV6_NIB_CONF_ROUTER. * - * @return A new or existing forwarding table entry with _nib_dr_entry_t::pfx - * set to @p pfx. + * @return A new or existing off-link entry with _nib_offl_entry_t::pfx set to + * @p pfx. * @return NULL, if no space is left. */ static inline _nib_offl_entry_t *_nib_ft_add(const ipv6_addr_t *next_hop, @@ -594,7 +592,7 @@ static inline _nib_offl_entry_t *_nib_ft_add(const ipv6_addr_t *next_hop, const ipv6_addr_t *pfx, unsigned pfx_len) { - return _nib_dst_add(next_hop, iface, pfx, pfx_len, _FT); + return _nib_offl_add(next_hop, iface, pfx, pfx_len, _FT); } /** @@ -608,7 +606,7 @@ static inline _nib_offl_entry_t *_nib_ft_add(const ipv6_addr_t *next_hop, */ static inline void _nib_ft_remove(_nib_offl_entry_t *nib_offl) { - _nib_dst_remove(nib_offl, _FT); + _nib_offl_remove(nib_offl, _FT); } #endif /* GNRC_IPV6_NIB_CONF_ROUTER */