[457] | 1 | /**
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| 2 | * @file
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| 3 | *
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| 4 | * Neighbor discovery and stateless address autoconfiguration for IPv6.
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| 5 | * Aims to be compliant with RFC 4861 (Neighbor discovery) and RFC 4862
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| 6 | * (Address autoconfiguration).
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| 7 | */
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| 8 |
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| 9 | /*
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| 10 | * Copyright (c) 2010 Inico Technologies Ltd.
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| 11 | * All rights reserved.
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| 12 | *
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| 13 | * Redistribution and use in source and binary forms, with or without modification,
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| 14 | * are permitted provided that the following conditions are met:
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| 15 | *
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| 16 | * 1. Redistributions of source code must retain the above copyright notice,
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| 17 | * this list of conditions and the following disclaimer.
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| 18 | * 2. Redistributions in binary form must reproduce the above copyright notice,
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| 19 | * this list of conditions and the following disclaimer in the documentation
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| 20 | * and/or other materials provided with the distribution.
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| 21 | * 3. The name of the author may not be used to endorse or promote products
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| 22 | * derived from this software without specific prior written permission.
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| 23 | *
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| 24 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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| 25 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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| 26 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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| 27 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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| 28 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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| 29 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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| 30 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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| 31 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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| 32 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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| 33 | * OF SUCH DAMAGE.
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| 34 | *
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| 35 | * This file is part of the lwIP TCP/IP stack.
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| 36 | *
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| 37 | * Author: Ivan Delamer <delamer@inicotech.com>
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| 38 | *
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| 39 | *
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| 40 | * Please coordinate changes and requests with Ivan Delamer
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| 41 | * <delamer@inicotech.com>
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| 42 | */
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| 43 |
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| 44 | #include "lwip/opt.h"
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| 45 |
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| 46 | #if LWIP_IPV6 /* don't build if not configured for use in lwipopts.h */
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| 47 |
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| 48 | #include "lwip/nd6.h"
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| 49 | #include "lwip/priv/nd6_priv.h"
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| 50 | #include "lwip/prot/nd6.h"
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| 51 | #include "lwip/prot/icmp6.h"
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| 52 | #include "lwip/pbuf.h"
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| 53 | #include "lwip/mem.h"
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| 54 | #include "lwip/memp.h"
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| 55 | #include "lwip/ip6.h"
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| 56 | #include "lwip/ip6_addr.h"
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| 57 | #include "lwip/inet_chksum.h"
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| 58 | #include "lwip/netif.h"
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| 59 | #include "lwip/icmp6.h"
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| 60 | #include "lwip/mld6.h"
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| 61 | #include "lwip/dhcp6.h"
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| 62 | #include "lwip/ip.h"
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| 63 | #include "lwip/stats.h"
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| 64 | #include "lwip/dns.h"
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| 65 |
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| 66 | #include <string.h>
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| 67 |
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| 68 | #ifdef LWIP_HOOK_FILENAME
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| 69 | #include LWIP_HOOK_FILENAME
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| 70 | #endif
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| 71 |
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| 72 | #if LWIP_IPV6_DUP_DETECT_ATTEMPTS > IP6_ADDR_TENTATIVE_COUNT_MASK
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| 73 | #error LWIP_IPV6_DUP_DETECT_ATTEMPTS > IP6_ADDR_TENTATIVE_COUNT_MASK
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| 74 | #endif
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| 75 |
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| 76 | /* Router tables. */
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| 77 | struct nd6_neighbor_cache_entry neighbor_cache[LWIP_ND6_NUM_NEIGHBORS];
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| 78 | struct nd6_destination_cache_entry destination_cache[LWIP_ND6_NUM_DESTINATIONS];
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| 79 | struct nd6_prefix_list_entry prefix_list[LWIP_ND6_NUM_PREFIXES];
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| 80 | struct nd6_router_list_entry default_router_list[LWIP_ND6_NUM_ROUTERS];
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| 81 |
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| 82 | /* Default values, can be updated by a RA message. */
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| 83 | u32_t reachable_time = LWIP_ND6_REACHABLE_TIME;
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| 84 | u32_t retrans_timer = LWIP_ND6_RETRANS_TIMER; /* @todo implement this value in timer */
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| 85 |
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| 86 | /* Index for cache entries. */
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| 87 | static u8_t nd6_cached_neighbor_index;
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| 88 | static netif_addr_idx_t nd6_cached_destination_index;
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| 89 |
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| 90 | /* Multicast address holder. */
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| 91 | static ip6_addr_t multicast_address;
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| 92 |
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| 93 | static u8_t nd6_tmr_rs_reduction;
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| 94 |
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| 95 | /* Static buffer to parse RA packet options */
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| 96 | union ra_options {
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| 97 | struct lladdr_option lladdr;
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| 98 | struct mtu_option mtu;
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| 99 | struct prefix_option prefix;
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| 100 | #if LWIP_ND6_RDNSS_MAX_DNS_SERVERS
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| 101 | struct rdnss_option rdnss;
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| 102 | #endif
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| 103 | };
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| 104 | static union ra_options nd6_ra_buffer;
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| 105 |
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| 106 | /* Forward declarations. */
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| 107 | static s8_t nd6_find_neighbor_cache_entry(const ip6_addr_t *ip6addr);
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| 108 | static s8_t nd6_new_neighbor_cache_entry(void);
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| 109 | static void nd6_free_neighbor_cache_entry(s8_t i);
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| 110 | static s16_t nd6_find_destination_cache_entry(const ip6_addr_t *ip6addr);
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| 111 | static s16_t nd6_new_destination_cache_entry(void);
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| 112 | static int nd6_is_prefix_in_netif(const ip6_addr_t *ip6addr, struct netif *netif);
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| 113 | static s8_t nd6_select_router(const ip6_addr_t *ip6addr, struct netif *netif);
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| 114 | static s8_t nd6_get_router(const ip6_addr_t *router_addr, struct netif *netif);
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| 115 | static s8_t nd6_new_router(const ip6_addr_t *router_addr, struct netif *netif);
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| 116 | static s8_t nd6_get_onlink_prefix(const ip6_addr_t *prefix, struct netif *netif);
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| 117 | static s8_t nd6_new_onlink_prefix(const ip6_addr_t *prefix, struct netif *netif);
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| 118 | static s8_t nd6_get_next_hop_entry(const ip6_addr_t *ip6addr, struct netif *netif);
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| 119 | static err_t nd6_queue_packet(s8_t neighbor_index, struct pbuf *q);
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| 120 |
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| 121 | #define ND6_SEND_FLAG_MULTICAST_DEST 0x01
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| 122 | #define ND6_SEND_FLAG_ALLNODES_DEST 0x02
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| 123 | #define ND6_SEND_FLAG_ANY_SRC 0x04
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| 124 | static void nd6_send_ns(struct netif *netif, const ip6_addr_t *target_addr, u8_t flags);
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| 125 | static void nd6_send_na(struct netif *netif, const ip6_addr_t *target_addr, u8_t flags);
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| 126 | static void nd6_send_neighbor_cache_probe(struct nd6_neighbor_cache_entry *entry, u8_t flags);
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| 127 | #if LWIP_IPV6_SEND_ROUTER_SOLICIT
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| 128 | static err_t nd6_send_rs(struct netif *netif);
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| 129 | #endif /* LWIP_IPV6_SEND_ROUTER_SOLICIT */
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| 130 |
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| 131 | #if LWIP_ND6_QUEUEING
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| 132 | static void nd6_free_q(struct nd6_q_entry *q);
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| 133 | #else /* LWIP_ND6_QUEUEING */
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| 134 | #define nd6_free_q(q) pbuf_free(q)
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| 135 | #endif /* LWIP_ND6_QUEUEING */
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| 136 | static void nd6_send_q(s8_t i);
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| 137 |
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| 138 |
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| 139 | /**
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| 140 | * A local address has been determined to be a duplicate. Take the appropriate
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| 141 | * action(s) on the address and the interface as a whole.
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| 142 | *
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| 143 | * @param netif the netif that owns the address
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| 144 | * @param addr_idx the index of the address detected to be a duplicate
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| 145 | */
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| 146 | static void
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| 147 | nd6_duplicate_addr_detected(struct netif *netif, s8_t addr_idx)
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| 148 | {
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| 149 |
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| 150 | /* Mark the address as duplicate, but leave its lifetimes alone. If this was
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| 151 | * a manually assigned address, it will remain in existence as duplicate, and
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| 152 | * as such be unusable for any practical purposes until manual intervention.
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| 153 | * If this was an autogenerated address, the address will follow normal
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| 154 | * expiration rules, and thus disappear once its valid lifetime expires. */
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| 155 | netif_ip6_addr_set_state(netif, addr_idx, IP6_ADDR_DUPLICATED);
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| 156 |
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| 157 | #if LWIP_IPV6_AUTOCONFIG
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| 158 | /* If the affected address was the link-local address that we use to generate
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| 159 | * all other addresses, then we should not continue to use those derived
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| 160 | * addresses either, so mark them as duplicate as well. For autoconfig-only
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| 161 | * setups, this will make the interface effectively unusable, approaching the
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| 162 | * intention of RFC 4862 Sec. 5.4.5. @todo implement the full requirements */
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| 163 | if (addr_idx == 0) {
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| 164 | s8_t i;
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| 165 | for (i = 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
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| 166 | if (!ip6_addr_isinvalid(netif_ip6_addr_state(netif, i)) &&
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| 167 | !netif_ip6_addr_isstatic(netif, i)) {
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| 168 | netif_ip6_addr_set_state(netif, i, IP6_ADDR_DUPLICATED);
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| 169 | }
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| 170 | }
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| 171 | }
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| 172 | #endif /* LWIP_IPV6_AUTOCONFIG */
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| 173 | }
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| 174 |
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| 175 | #if LWIP_IPV6_AUTOCONFIG
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| 176 | /**
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| 177 | * We received a router advertisement that contains a prefix with the
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| 178 | * autoconfiguration flag set. Add or update an associated autogenerated
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| 179 | * address.
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| 180 | *
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| 181 | * @param netif the netif on which the router advertisement arrived
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| 182 | * @param prefix_opt a pointer to the prefix option data
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| 183 | * @param prefix_addr an aligned copy of the prefix address
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| 184 | */
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| 185 | static void
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| 186 | nd6_process_autoconfig_prefix(struct netif *netif,
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| 187 | struct prefix_option *prefix_opt, const ip6_addr_t *prefix_addr)
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| 188 | {
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| 189 | ip6_addr_t ip6addr;
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| 190 | u32_t valid_life, pref_life;
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| 191 | u8_t addr_state;
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| 192 | s8_t i, free_idx;
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| 193 |
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| 194 | /* The caller already checks RFC 4862 Sec. 5.5.3 points (a) and (b). We do
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| 195 | * the rest, starting with checks for (c) and (d) here. */
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| 196 | valid_life = lwip_htonl(prefix_opt->valid_lifetime);
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| 197 | pref_life = lwip_htonl(prefix_opt->preferred_lifetime);
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| 198 | if (pref_life > valid_life || prefix_opt->prefix_length != 64) {
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| 199 | return; /* silently ignore this prefix for autoconfiguration purposes */
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| 200 | }
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| 201 |
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| 202 | /* If an autogenerated address already exists for this prefix, update its
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| 203 | * lifetimes. An address is considered autogenerated if 1) it is not static
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| 204 | * (i.e., manually assigned), and 2) there is an advertised autoconfiguration
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| 205 | * prefix for it (the one we are processing here). This does not necessarily
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| 206 | * exclude the possibility that the address was actually assigned by, say,
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| 207 | * DHCPv6. If that distinction becomes important in the future, more state
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| 208 | * must be kept. As explained elsewhere we also update lifetimes of tentative
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| 209 | * and duplicate addresses. Skip address slot 0 (the link-local address). */
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| 210 | for (i = 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
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| 211 | addr_state = netif_ip6_addr_state(netif, i);
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| 212 | if (!ip6_addr_isinvalid(addr_state) && !netif_ip6_addr_isstatic(netif, i) &&
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| 213 | ip6_addr_netcmp(prefix_addr, netif_ip6_addr(netif, i))) {
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| 214 | /* Update the valid lifetime, as per RFC 4862 Sec. 5.5.3 point (e).
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| 215 | * The valid lifetime will never drop to zero as a result of this. */
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| 216 | u32_t remaining_life = netif_ip6_addr_valid_life(netif, i);
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| 217 | if (valid_life > ND6_2HRS || valid_life > remaining_life) {
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| 218 | netif_ip6_addr_set_valid_life(netif, i, valid_life);
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| 219 | } else if (remaining_life > ND6_2HRS) {
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| 220 | netif_ip6_addr_set_valid_life(netif, i, ND6_2HRS);
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| 221 | }
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| 222 | LWIP_ASSERT("bad valid lifetime", !netif_ip6_addr_isstatic(netif, i));
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| 223 | /* Update the preferred lifetime. No bounds checks are needed here. In
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| 224 | * rare cases the advertisement may un-deprecate the address, though.
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| 225 | * Deprecation is left to the timer code where it is handled anyway. */
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| 226 | if (pref_life > 0 && addr_state == IP6_ADDR_DEPRECATED) {
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| 227 | netif_ip6_addr_set_state(netif, i, IP6_ADDR_PREFERRED);
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| 228 | }
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| 229 | netif_ip6_addr_set_pref_life(netif, i, pref_life);
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| 230 | return; /* there should be at most one matching address */
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| 231 | }
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| 232 | }
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| 233 |
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| 234 | /* No autogenerated address exists for this prefix yet. See if we can add a
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| 235 | * new one. However, if IPv6 autoconfiguration is administratively disabled,
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| 236 | * do not generate new addresses, but do keep updating lifetimes for existing
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| 237 | * addresses. Also, when adding new addresses, we must protect explicitly
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| 238 | * against a valid lifetime of zero, because again, we use that as a special
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| 239 | * value. The generated address would otherwise expire immediately anyway.
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| 240 | * Finally, the original link-local address must be usable at all. We start
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| 241 | * creating addresses even if the link-local address is still in tentative
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| 242 | * state though, and deal with the fallout of that upon DAD collision. */
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| 243 | addr_state = netif_ip6_addr_state(netif, 0);
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| 244 | if (!netif->ip6_autoconfig_enabled || valid_life == IP6_ADDR_LIFE_STATIC ||
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| 245 | ip6_addr_isinvalid(addr_state) || ip6_addr_isduplicated(addr_state)) {
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| 246 | return;
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| 247 | }
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| 248 |
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| 249 | /* Construct the new address that we intend to use, and then see if that
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| 250 | * address really does not exist. It might have been added manually, after
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| 251 | * all. As a side effect, find a free slot. Note that we cannot use
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| 252 | * netif_add_ip6_address() here, as it would return ERR_OK if the address
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| 253 | * already did exist, resulting in that address being given lifetimes. */
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| 254 | IP6_ADDR(&ip6addr, prefix_addr->addr[0], prefix_addr->addr[1],
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| 255 | netif_ip6_addr(netif, 0)->addr[2], netif_ip6_addr(netif, 0)->addr[3]);
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| 256 | ip6_addr_assign_zone(&ip6addr, IP6_UNICAST, netif);
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| 257 |
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| 258 | free_idx = 0;
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| 259 | for (i = 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
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| 260 | if (!ip6_addr_isinvalid(netif_ip6_addr_state(netif, i))) {
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| 261 | if (ip6_addr_cmp(&ip6addr, netif_ip6_addr(netif, i))) {
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| 262 | return; /* formed address already exists */
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| 263 | }
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| 264 | } else if (free_idx == 0) {
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| 265 | free_idx = i;
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| 266 | }
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| 267 | }
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| 268 | if (free_idx == 0) {
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| 269 | return; /* no address slots available, try again on next advertisement */
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| 270 | }
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| 271 |
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| 272 | /* Assign the new address to the interface. */
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| 273 | ip_addr_copy_from_ip6(netif->ip6_addr[free_idx], ip6addr);
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| 274 | netif_ip6_addr_set_valid_life(netif, free_idx, valid_life);
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| 275 | netif_ip6_addr_set_pref_life(netif, free_idx, pref_life);
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| 276 | netif_ip6_addr_set_state(netif, free_idx, IP6_ADDR_TENTATIVE);
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| 277 | }
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| 278 | #endif /* LWIP_IPV6_AUTOCONFIG */
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| 279 |
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| 280 | /**
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| 281 | * Process an incoming neighbor discovery message
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| 282 | *
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| 283 | * @param p the nd packet, p->payload pointing to the icmpv6 header
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| 284 | * @param inp the netif on which this packet was received
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| 285 | */
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| 286 | void
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| 287 | nd6_input(struct pbuf *p, struct netif *inp)
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| 288 | {
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| 289 | u8_t msg_type;
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| 290 | s8_t i;
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| 291 | s16_t dest_idx;
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| 292 |
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| 293 | ND6_STATS_INC(nd6.recv);
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| 294 |
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| 295 | msg_type = *((u8_t *)p->payload);
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| 296 | switch (msg_type) {
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| 297 | case ICMP6_TYPE_NA: /* Neighbor Advertisement. */
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| 298 | {
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| 299 | struct na_header *na_hdr;
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| 300 | struct lladdr_option *lladdr_opt;
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| 301 | ip6_addr_t target_address;
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| 302 |
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| 303 | /* Check that na header fits in packet. */
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| 304 | if (p->len < (sizeof(struct na_header))) {
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| 305 | /* @todo debug message */
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| 306 | pbuf_free(p);
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| 307 | ND6_STATS_INC(nd6.lenerr);
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| 308 | ND6_STATS_INC(nd6.drop);
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| 309 | return;
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| 310 | }
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| 311 |
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| 312 | na_hdr = (struct na_header *)p->payload;
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| 313 |
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| 314 | /* Create an aligned, zoned copy of the target address. */
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| 315 | ip6_addr_copy_from_packed(target_address, na_hdr->target_address);
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| 316 | ip6_addr_assign_zone(&target_address, IP6_UNICAST, inp);
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| 317 |
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| 318 | /* Check a subset of the other RFC 4861 Sec. 7.1.2 requirements. */
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| 319 | if (IP6H_HOPLIM(ip6_current_header()) != ND6_HOPLIM || na_hdr->code != 0 ||
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| 320 | ip6_addr_ismulticast(&target_address)) {
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| 321 | pbuf_free(p);
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| 322 | ND6_STATS_INC(nd6.proterr);
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| 323 | ND6_STATS_INC(nd6.drop);
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| 324 | return;
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| 325 | }
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| 326 |
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| 327 | /* @todo RFC MUST: if IP destination is multicast, Solicited flag is zero */
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| 328 | /* @todo RFC MUST: all included options have a length greater than zero */
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| 329 |
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| 330 | /* Unsolicited NA?*/
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| 331 | if (ip6_addr_ismulticast(ip6_current_dest_addr())) {
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| 332 | /* This is an unsolicited NA.
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| 333 | * link-layer changed?
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| 334 | * part of DAD mechanism? */
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| 335 |
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| 336 | #if LWIP_IPV6_DUP_DETECT_ATTEMPTS
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| 337 | /* If the target address matches this netif, it is a DAD response. */
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| 338 | for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
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| 339 | if (!ip6_addr_isinvalid(netif_ip6_addr_state(inp, i)) &&
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| 340 | !ip6_addr_isduplicated(netif_ip6_addr_state(inp, i)) &&
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| 341 | ip6_addr_cmp(&target_address, netif_ip6_addr(inp, i))) {
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| 342 | /* We are using a duplicate address. */
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| 343 | nd6_duplicate_addr_detected(inp, i);
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| 344 |
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| 345 | pbuf_free(p);
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| 346 | return;
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| 347 | }
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| 348 | }
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| 349 | #endif /* LWIP_IPV6_DUP_DETECT_ATTEMPTS */
|
---|
| 350 |
|
---|
| 351 | /* Check that link-layer address option also fits in packet. */
|
---|
| 352 | if (p->len < (sizeof(struct na_header) + 2)) {
|
---|
| 353 | /* @todo debug message */
|
---|
| 354 | pbuf_free(p);
|
---|
| 355 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 356 | ND6_STATS_INC(nd6.drop);
|
---|
| 357 | return;
|
---|
| 358 | }
|
---|
| 359 |
|
---|
| 360 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct na_header));
|
---|
| 361 |
|
---|
| 362 | if (p->len < (sizeof(struct na_header) + (lladdr_opt->length << 3))) {
|
---|
| 363 | /* @todo debug message */
|
---|
| 364 | pbuf_free(p);
|
---|
| 365 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 366 | ND6_STATS_INC(nd6.drop);
|
---|
| 367 | return;
|
---|
| 368 | }
|
---|
| 369 |
|
---|
| 370 | /* This is an unsolicited NA, most likely there was a LLADDR change. */
|
---|
| 371 | i = nd6_find_neighbor_cache_entry(&target_address);
|
---|
| 372 | if (i >= 0) {
|
---|
| 373 | if (na_hdr->flags & ND6_FLAG_OVERRIDE) {
|
---|
| 374 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 375 | }
|
---|
| 376 | }
|
---|
| 377 | } else {
|
---|
| 378 | /* This is a solicited NA.
|
---|
| 379 | * neighbor address resolution response?
|
---|
| 380 | * neighbor unreachability detection response? */
|
---|
| 381 |
|
---|
| 382 | /* Find the cache entry corresponding to this na. */
|
---|
| 383 | i = nd6_find_neighbor_cache_entry(&target_address);
|
---|
| 384 | if (i < 0) {
|
---|
| 385 | /* We no longer care about this target address. drop it. */
|
---|
| 386 | pbuf_free(p);
|
---|
| 387 | return;
|
---|
| 388 | }
|
---|
| 389 |
|
---|
| 390 | /* Update cache entry. */
|
---|
| 391 | if ((na_hdr->flags & ND6_FLAG_OVERRIDE) ||
|
---|
| 392 | (neighbor_cache[i].state == ND6_INCOMPLETE)) {
|
---|
| 393 | /* Check that link-layer address option also fits in packet. */
|
---|
| 394 | if (p->len < (sizeof(struct na_header) + 2)) {
|
---|
| 395 | /* @todo debug message */
|
---|
| 396 | pbuf_free(p);
|
---|
| 397 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 398 | ND6_STATS_INC(nd6.drop);
|
---|
| 399 | return;
|
---|
| 400 | }
|
---|
| 401 |
|
---|
| 402 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct na_header));
|
---|
| 403 |
|
---|
| 404 | if (p->len < (sizeof(struct na_header) + (lladdr_opt->length << 3))) {
|
---|
| 405 | /* @todo debug message */
|
---|
| 406 | pbuf_free(p);
|
---|
| 407 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 408 | ND6_STATS_INC(nd6.drop);
|
---|
| 409 | return;
|
---|
| 410 | }
|
---|
| 411 |
|
---|
| 412 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 413 | }
|
---|
| 414 |
|
---|
| 415 | neighbor_cache[i].netif = inp;
|
---|
| 416 | neighbor_cache[i].state = ND6_REACHABLE;
|
---|
| 417 | neighbor_cache[i].counter.reachable_time = reachable_time;
|
---|
| 418 |
|
---|
| 419 | /* Send queued packets, if any. */
|
---|
| 420 | if (neighbor_cache[i].q != NULL) {
|
---|
| 421 | nd6_send_q(i);
|
---|
| 422 | }
|
---|
| 423 | }
|
---|
| 424 |
|
---|
| 425 | break; /* ICMP6_TYPE_NA */
|
---|
| 426 | }
|
---|
| 427 | case ICMP6_TYPE_NS: /* Neighbor solicitation. */
|
---|
| 428 | {
|
---|
| 429 | struct ns_header *ns_hdr;
|
---|
| 430 | struct lladdr_option *lladdr_opt;
|
---|
| 431 | ip6_addr_t target_address;
|
---|
| 432 | u8_t accepted;
|
---|
| 433 |
|
---|
| 434 | /* Check that ns header fits in packet. */
|
---|
| 435 | if (p->len < sizeof(struct ns_header)) {
|
---|
| 436 | /* @todo debug message */
|
---|
| 437 | pbuf_free(p);
|
---|
| 438 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 439 | ND6_STATS_INC(nd6.drop);
|
---|
| 440 | return;
|
---|
| 441 | }
|
---|
| 442 |
|
---|
| 443 | ns_hdr = (struct ns_header *)p->payload;
|
---|
| 444 |
|
---|
| 445 | /* Create an aligned, zoned copy of the target address. */
|
---|
| 446 | ip6_addr_copy_from_packed(target_address, ns_hdr->target_address);
|
---|
| 447 | ip6_addr_assign_zone(&target_address, IP6_UNICAST, inp);
|
---|
| 448 |
|
---|
| 449 | /* Check a subset of the other RFC 4861 Sec. 7.1.1 requirements. */
|
---|
| 450 | if (IP6H_HOPLIM(ip6_current_header()) != ND6_HOPLIM || ns_hdr->code != 0 ||
|
---|
| 451 | ip6_addr_ismulticast(&target_address)) {
|
---|
| 452 | pbuf_free(p);
|
---|
| 453 | ND6_STATS_INC(nd6.proterr);
|
---|
| 454 | ND6_STATS_INC(nd6.drop);
|
---|
| 455 | return;
|
---|
| 456 | }
|
---|
| 457 |
|
---|
| 458 | /* @todo RFC MUST: all included options have a length greater than zero */
|
---|
| 459 | /* @todo RFC MUST: if IP source is 'any', destination is solicited-node multicast address */
|
---|
| 460 | /* @todo RFC MUST: if IP source is 'any', there is no source LL address option */
|
---|
| 461 |
|
---|
| 462 | /* Check if there is a link-layer address provided. Only point to it if in this buffer. */
|
---|
| 463 | if (p->len >= (sizeof(struct ns_header) + 2)) {
|
---|
| 464 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct ns_header));
|
---|
| 465 | if (p->len < (sizeof(struct ns_header) + (lladdr_opt->length << 3))) {
|
---|
| 466 | lladdr_opt = NULL;
|
---|
| 467 | }
|
---|
| 468 | } else {
|
---|
| 469 | lladdr_opt = NULL;
|
---|
| 470 | }
|
---|
| 471 |
|
---|
| 472 | /* Check if the target address is configured on the receiving netif. */
|
---|
| 473 | accepted = 0;
|
---|
| 474 | for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
|
---|
| 475 | if ((ip6_addr_isvalid(netif_ip6_addr_state(inp, i)) ||
|
---|
| 476 | (ip6_addr_istentative(netif_ip6_addr_state(inp, i)) &&
|
---|
| 477 | ip6_addr_isany(ip6_current_src_addr()))) &&
|
---|
| 478 | ip6_addr_cmp(&target_address, netif_ip6_addr(inp, i))) {
|
---|
| 479 | accepted = 1;
|
---|
| 480 | break;
|
---|
| 481 | }
|
---|
| 482 | }
|
---|
| 483 |
|
---|
| 484 | /* NS not for us? */
|
---|
| 485 | if (!accepted) {
|
---|
| 486 | pbuf_free(p);
|
---|
| 487 | return;
|
---|
| 488 | }
|
---|
| 489 |
|
---|
| 490 | /* Check for ANY address in src (DAD algorithm). */
|
---|
| 491 | if (ip6_addr_isany(ip6_current_src_addr())) {
|
---|
| 492 | /* Sender is validating this address. */
|
---|
| 493 | for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
|
---|
| 494 | if (!ip6_addr_isinvalid(netif_ip6_addr_state(inp, i)) &&
|
---|
| 495 | ip6_addr_cmp(&target_address, netif_ip6_addr(inp, i))) {
|
---|
| 496 | /* Send a NA back so that the sender does not use this address. */
|
---|
| 497 | nd6_send_na(inp, netif_ip6_addr(inp, i), ND6_FLAG_OVERRIDE | ND6_SEND_FLAG_ALLNODES_DEST);
|
---|
| 498 | if (ip6_addr_istentative(netif_ip6_addr_state(inp, i))) {
|
---|
| 499 | /* We shouldn't use this address either. */
|
---|
| 500 | nd6_duplicate_addr_detected(inp, i);
|
---|
| 501 | }
|
---|
| 502 | }
|
---|
| 503 | }
|
---|
| 504 | } else {
|
---|
| 505 | /* Sender is trying to resolve our address. */
|
---|
| 506 | /* Verify that they included their own link-layer address. */
|
---|
| 507 | if (lladdr_opt == NULL) {
|
---|
| 508 | /* Not a valid message. */
|
---|
| 509 | pbuf_free(p);
|
---|
| 510 | ND6_STATS_INC(nd6.proterr);
|
---|
| 511 | ND6_STATS_INC(nd6.drop);
|
---|
| 512 | return;
|
---|
| 513 | }
|
---|
| 514 |
|
---|
| 515 | i = nd6_find_neighbor_cache_entry(ip6_current_src_addr());
|
---|
| 516 | if (i>= 0) {
|
---|
| 517 | /* We already have a record for the solicitor. */
|
---|
| 518 | if (neighbor_cache[i].state == ND6_INCOMPLETE) {
|
---|
| 519 | neighbor_cache[i].netif = inp;
|
---|
| 520 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 521 |
|
---|
| 522 | /* Delay probe in case we get confirmation of reachability from upper layer (TCP). */
|
---|
| 523 | neighbor_cache[i].state = ND6_DELAY;
|
---|
| 524 | neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
|
---|
| 525 | }
|
---|
| 526 | } else {
|
---|
| 527 | /* Add their IPv6 address and link-layer address to neighbor cache.
|
---|
| 528 | * We will need it at least to send a unicast NA message, but most
|
---|
| 529 | * likely we will also be communicating with this node soon. */
|
---|
| 530 | i = nd6_new_neighbor_cache_entry();
|
---|
| 531 | if (i < 0) {
|
---|
| 532 | /* We couldn't assign a cache entry for this neighbor.
|
---|
| 533 | * we won't be able to reply. drop it. */
|
---|
| 534 | pbuf_free(p);
|
---|
| 535 | ND6_STATS_INC(nd6.memerr);
|
---|
| 536 | return;
|
---|
| 537 | }
|
---|
| 538 | neighbor_cache[i].netif = inp;
|
---|
| 539 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 540 | ip6_addr_set(&(neighbor_cache[i].next_hop_address), ip6_current_src_addr());
|
---|
| 541 |
|
---|
| 542 | /* Receiving a message does not prove reachability: only in one direction.
|
---|
| 543 | * Delay probe in case we get confirmation of reachability from upper layer (TCP). */
|
---|
| 544 | neighbor_cache[i].state = ND6_DELAY;
|
---|
| 545 | neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
|
---|
| 546 | }
|
---|
| 547 |
|
---|
| 548 | /* Send back a NA for us. Allocate the reply pbuf. */
|
---|
| 549 | nd6_send_na(inp, &target_address, ND6_FLAG_SOLICITED | ND6_FLAG_OVERRIDE);
|
---|
| 550 | }
|
---|
| 551 |
|
---|
| 552 | break; /* ICMP6_TYPE_NS */
|
---|
| 553 | }
|
---|
| 554 | case ICMP6_TYPE_RA: /* Router Advertisement. */
|
---|
| 555 | {
|
---|
| 556 | struct ra_header *ra_hdr;
|
---|
| 557 | u8_t *buffer; /* Used to copy options. */
|
---|
| 558 | u16_t offset;
|
---|
| 559 | #if LWIP_ND6_RDNSS_MAX_DNS_SERVERS
|
---|
| 560 | /* There can be multiple RDNSS options per RA */
|
---|
| 561 | u8_t rdnss_server_idx = 0;
|
---|
| 562 | #endif /* LWIP_ND6_RDNSS_MAX_DNS_SERVERS */
|
---|
| 563 |
|
---|
| 564 | /* Check that RA header fits in packet. */
|
---|
| 565 | if (p->len < sizeof(struct ra_header)) {
|
---|
| 566 | /* @todo debug message */
|
---|
| 567 | pbuf_free(p);
|
---|
| 568 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 569 | ND6_STATS_INC(nd6.drop);
|
---|
| 570 | return;
|
---|
| 571 | }
|
---|
| 572 |
|
---|
| 573 | ra_hdr = (struct ra_header *)p->payload;
|
---|
| 574 |
|
---|
| 575 | /* Check a subset of the other RFC 4861 Sec. 6.1.2 requirements. */
|
---|
| 576 | if (!ip6_addr_islinklocal(ip6_current_src_addr()) ||
|
---|
| 577 | IP6H_HOPLIM(ip6_current_header()) != ND6_HOPLIM || ra_hdr->code != 0) {
|
---|
| 578 | pbuf_free(p);
|
---|
| 579 | ND6_STATS_INC(nd6.proterr);
|
---|
| 580 | ND6_STATS_INC(nd6.drop);
|
---|
| 581 | return;
|
---|
| 582 | }
|
---|
| 583 |
|
---|
| 584 | /* @todo RFC MUST: all included options have a length greater than zero */
|
---|
| 585 |
|
---|
| 586 | /* If we are sending RS messages, stop. */
|
---|
| 587 | #if LWIP_IPV6_SEND_ROUTER_SOLICIT
|
---|
| 588 | /* ensure at least one solicitation is sent (see RFC 4861, ch. 6.3.7) */
|
---|
| 589 | if ((inp->rs_count < LWIP_ND6_MAX_MULTICAST_SOLICIT) ||
|
---|
| 590 | (nd6_send_rs(inp) == ERR_OK)) {
|
---|
| 591 | inp->rs_count = 0;
|
---|
| 592 | } else {
|
---|
| 593 | inp->rs_count = 1;
|
---|
| 594 | }
|
---|
| 595 | #endif /* LWIP_IPV6_SEND_ROUTER_SOLICIT */
|
---|
| 596 |
|
---|
| 597 | /* Get the matching default router entry. */
|
---|
| 598 | i = nd6_get_router(ip6_current_src_addr(), inp);
|
---|
| 599 | if (i < 0) {
|
---|
| 600 | /* Create a new router entry. */
|
---|
| 601 | i = nd6_new_router(ip6_current_src_addr(), inp);
|
---|
| 602 | }
|
---|
| 603 |
|
---|
| 604 | if (i < 0) {
|
---|
| 605 | /* Could not create a new router entry. */
|
---|
| 606 | pbuf_free(p);
|
---|
| 607 | ND6_STATS_INC(nd6.memerr);
|
---|
| 608 | return;
|
---|
| 609 | }
|
---|
| 610 |
|
---|
| 611 | /* Re-set invalidation timer. */
|
---|
| 612 | default_router_list[i].invalidation_timer = lwip_htons(ra_hdr->router_lifetime);
|
---|
| 613 |
|
---|
| 614 | /* Re-set default timer values. */
|
---|
| 615 | #if LWIP_ND6_ALLOW_RA_UPDATES
|
---|
| 616 | if (ra_hdr->retrans_timer > 0) {
|
---|
| 617 | retrans_timer = lwip_htonl(ra_hdr->retrans_timer);
|
---|
| 618 | }
|
---|
| 619 | if (ra_hdr->reachable_time > 0) {
|
---|
| 620 | reachable_time = lwip_htonl(ra_hdr->reachable_time);
|
---|
| 621 | }
|
---|
| 622 | #endif /* LWIP_ND6_ALLOW_RA_UPDATES */
|
---|
| 623 |
|
---|
| 624 | /* @todo set default hop limit... */
|
---|
| 625 | /* ra_hdr->current_hop_limit;*/
|
---|
| 626 |
|
---|
| 627 | /* Update flags in local entry (incl. preference). */
|
---|
| 628 | default_router_list[i].flags = ra_hdr->flags;
|
---|
| 629 |
|
---|
| 630 | #if LWIP_IPV6_DHCP6
|
---|
| 631 | /* Trigger DHCPv6 if enabled */
|
---|
| 632 | dhcp6_nd6_ra_trigger(inp, ra_hdr->flags & ND6_RA_FLAG_MANAGED_ADDR_CONFIG,
|
---|
| 633 | ra_hdr->flags & ND6_RA_FLAG_OTHER_CONFIG);
|
---|
| 634 | #endif
|
---|
| 635 |
|
---|
| 636 | /* Offset to options. */
|
---|
| 637 | offset = sizeof(struct ra_header);
|
---|
| 638 |
|
---|
| 639 | /* Process each option. */
|
---|
| 640 | while ((p->tot_len - offset) >= 2) {
|
---|
| 641 | u8_t option_type;
|
---|
| 642 | u16_t option_len;
|
---|
| 643 | int option_len8 = pbuf_try_get_at(p, offset + 1);
|
---|
| 644 | if (option_len8 <= 0) {
|
---|
| 645 | /* read beyond end or zero length */
|
---|
| 646 | goto lenerr_drop_free_return;
|
---|
| 647 | }
|
---|
| 648 | option_len = ((u8_t)option_len8) << 3;
|
---|
| 649 | if (option_len > p->tot_len - offset) {
|
---|
| 650 | /* short packet (option does not fit in) */
|
---|
| 651 | goto lenerr_drop_free_return;
|
---|
| 652 | }
|
---|
| 653 | if (p->len == p->tot_len) {
|
---|
| 654 | /* no need to copy from contiguous pbuf */
|
---|
| 655 | buffer = &((u8_t*)p->payload)[offset];
|
---|
| 656 | } else {
|
---|
| 657 | /* check if this option fits into our buffer */
|
---|
| 658 | if (option_len > sizeof(nd6_ra_buffer)) {
|
---|
| 659 | option_type = pbuf_get_at(p, offset);
|
---|
| 660 | /* invalid option length */
|
---|
| 661 | if (option_type != ND6_OPTION_TYPE_RDNSS) {
|
---|
| 662 | goto lenerr_drop_free_return;
|
---|
| 663 | }
|
---|
| 664 | /* we allow RDNSS option to be longer - we'll just drop some servers */
|
---|
| 665 | option_len = sizeof(nd6_ra_buffer);
|
---|
| 666 | }
|
---|
| 667 | buffer = (u8_t*)&nd6_ra_buffer;
|
---|
| 668 | option_len = pbuf_copy_partial(p, &nd6_ra_buffer, option_len, offset);
|
---|
| 669 | }
|
---|
| 670 | option_type = buffer[0];
|
---|
| 671 | switch (option_type) {
|
---|
| 672 | case ND6_OPTION_TYPE_SOURCE_LLADDR:
|
---|
| 673 | {
|
---|
| 674 | struct lladdr_option *lladdr_opt;
|
---|
| 675 | if (option_len < sizeof(struct lladdr_option)) {
|
---|
| 676 | goto lenerr_drop_free_return;
|
---|
| 677 | }
|
---|
| 678 | lladdr_opt = (struct lladdr_option *)buffer;
|
---|
| 679 | if ((default_router_list[i].neighbor_entry != NULL) &&
|
---|
| 680 | (default_router_list[i].neighbor_entry->state == ND6_INCOMPLETE)) {
|
---|
| 681 | SMEMCPY(default_router_list[i].neighbor_entry->lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 682 | default_router_list[i].neighbor_entry->state = ND6_REACHABLE;
|
---|
| 683 | default_router_list[i].neighbor_entry->counter.reachable_time = reachable_time;
|
---|
| 684 | }
|
---|
| 685 | break;
|
---|
| 686 | }
|
---|
| 687 | case ND6_OPTION_TYPE_MTU:
|
---|
| 688 | {
|
---|
| 689 | struct mtu_option *mtu_opt;
|
---|
| 690 | u32_t mtu32;
|
---|
| 691 | if (option_len < sizeof(struct mtu_option)) {
|
---|
| 692 | goto lenerr_drop_free_return;
|
---|
| 693 | }
|
---|
| 694 | mtu_opt = (struct mtu_option *)buffer;
|
---|
| 695 | mtu32 = lwip_htonl(mtu_opt->mtu);
|
---|
| 696 | if ((mtu32 >= 1280) && (mtu32 <= 0xffff)) {
|
---|
| 697 | #if LWIP_ND6_ALLOW_RA_UPDATES
|
---|
| 698 | if (inp->mtu) {
|
---|
| 699 | /* don't set the mtu for IPv6 higher than the netif driver supports */
|
---|
| 700 | inp->mtu6 = LWIP_MIN(inp->mtu, (u16_t)mtu32);
|
---|
| 701 | } else {
|
---|
| 702 | inp->mtu6 = (u16_t)mtu32;
|
---|
| 703 | }
|
---|
| 704 | #endif /* LWIP_ND6_ALLOW_RA_UPDATES */
|
---|
| 705 | }
|
---|
| 706 | break;
|
---|
| 707 | }
|
---|
| 708 | case ND6_OPTION_TYPE_PREFIX_INFO:
|
---|
| 709 | {
|
---|
| 710 | struct prefix_option *prefix_opt;
|
---|
| 711 | ip6_addr_t prefix_addr;
|
---|
| 712 | if (option_len < sizeof(struct prefix_option)) {
|
---|
| 713 | goto lenerr_drop_free_return;
|
---|
| 714 | }
|
---|
| 715 |
|
---|
| 716 | prefix_opt = (struct prefix_option *)buffer;
|
---|
| 717 |
|
---|
| 718 | /* Get a memory-aligned copy of the prefix. */
|
---|
| 719 | ip6_addr_copy_from_packed(prefix_addr, prefix_opt->prefix);
|
---|
| 720 | ip6_addr_assign_zone(&prefix_addr, IP6_UNICAST, inp);
|
---|
| 721 |
|
---|
| 722 | if (!ip6_addr_islinklocal(&prefix_addr)) {
|
---|
| 723 | if ((prefix_opt->flags & ND6_PREFIX_FLAG_ON_LINK) &&
|
---|
| 724 | (prefix_opt->prefix_length == 64)) {
|
---|
| 725 | /* Add to on-link prefix list. */
|
---|
| 726 | u32_t valid_life;
|
---|
| 727 | s8_t prefix;
|
---|
| 728 |
|
---|
| 729 | valid_life = lwip_htonl(prefix_opt->valid_lifetime);
|
---|
| 730 |
|
---|
| 731 | /* find cache entry for this prefix. */
|
---|
| 732 | prefix = nd6_get_onlink_prefix(&prefix_addr, inp);
|
---|
| 733 | if (prefix < 0 && valid_life > 0) {
|
---|
| 734 | /* Create a new cache entry. */
|
---|
| 735 | prefix = nd6_new_onlink_prefix(&prefix_addr, inp);
|
---|
| 736 | }
|
---|
| 737 | if (prefix >= 0) {
|
---|
| 738 | prefix_list[prefix].invalidation_timer = valid_life;
|
---|
| 739 | }
|
---|
| 740 | }
|
---|
| 741 | #if LWIP_IPV6_AUTOCONFIG
|
---|
| 742 | if (prefix_opt->flags & ND6_PREFIX_FLAG_AUTONOMOUS) {
|
---|
| 743 | /* Perform processing for autoconfiguration. */
|
---|
| 744 | nd6_process_autoconfig_prefix(inp, prefix_opt, &prefix_addr);
|
---|
| 745 | }
|
---|
| 746 | #endif /* LWIP_IPV6_AUTOCONFIG */
|
---|
| 747 | }
|
---|
| 748 |
|
---|
| 749 | break;
|
---|
| 750 | }
|
---|
| 751 | case ND6_OPTION_TYPE_ROUTE_INFO:
|
---|
| 752 | /* @todo implement preferred routes.
|
---|
| 753 | struct route_option * route_opt;
|
---|
| 754 | route_opt = (struct route_option *)buffer;*/
|
---|
| 755 |
|
---|
| 756 | break;
|
---|
| 757 | #if LWIP_ND6_RDNSS_MAX_DNS_SERVERS
|
---|
| 758 | case ND6_OPTION_TYPE_RDNSS:
|
---|
| 759 | {
|
---|
| 760 | u8_t num, n;
|
---|
| 761 | u16_t copy_offset = offset + SIZEOF_RDNSS_OPTION_BASE;
|
---|
| 762 | struct rdnss_option * rdnss_opt;
|
---|
| 763 | if (option_len < SIZEOF_RDNSS_OPTION_BASE) {
|
---|
| 764 | goto lenerr_drop_free_return;
|
---|
| 765 | }
|
---|
| 766 |
|
---|
| 767 | rdnss_opt = (struct rdnss_option *)buffer;
|
---|
| 768 | num = (rdnss_opt->length - 1) / 2;
|
---|
| 769 | for (n = 0; (rdnss_server_idx < DNS_MAX_SERVERS) && (n < num); n++) {
|
---|
| 770 | ip_addr_t rdnss_address;
|
---|
| 771 |
|
---|
| 772 | /* Copy directly from pbuf to get an aligned, zoned copy of the prefix. */
|
---|
| 773 | if (pbuf_copy_partial(p, &rdnss_address, sizeof(ip6_addr_p_t), copy_offset) == sizeof(ip6_addr_p_t)) {
|
---|
| 774 | IP_SET_TYPE_VAL(rdnss_address, IPADDR_TYPE_V6);
|
---|
| 775 | ip6_addr_assign_zone(ip_2_ip6(&rdnss_address), IP6_UNKNOWN, inp);
|
---|
| 776 |
|
---|
| 777 | if (htonl(rdnss_opt->lifetime) > 0) {
|
---|
| 778 | /* TODO implement Lifetime > 0 */
|
---|
| 779 | dns_setserver(rdnss_server_idx++, &rdnss_address);
|
---|
| 780 | } else {
|
---|
| 781 | /* TODO implement DNS removal in dns.c */
|
---|
| 782 | u8_t s;
|
---|
| 783 | for (s = 0; s < DNS_MAX_SERVERS; s++) {
|
---|
| 784 | const ip_addr_t *addr = dns_getserver(s);
|
---|
| 785 | if(ip_addr_cmp(addr, &rdnss_address)) {
|
---|
| 786 | dns_setserver(s, NULL);
|
---|
| 787 | }
|
---|
| 788 | }
|
---|
| 789 | }
|
---|
| 790 | }
|
---|
| 791 | }
|
---|
| 792 | break;
|
---|
| 793 | }
|
---|
| 794 | #endif /* LWIP_ND6_RDNSS_MAX_DNS_SERVERS */
|
---|
| 795 | default:
|
---|
| 796 | /* Unrecognized option, abort. */
|
---|
| 797 | ND6_STATS_INC(nd6.proterr);
|
---|
| 798 | break;
|
---|
| 799 | }
|
---|
| 800 | /* option length is checked earlier to be non-zero to make sure loop ends */
|
---|
| 801 | offset += 8 * (u8_t)option_len8;
|
---|
| 802 | }
|
---|
| 803 |
|
---|
| 804 | break; /* ICMP6_TYPE_RA */
|
---|
| 805 | }
|
---|
| 806 | case ICMP6_TYPE_RD: /* Redirect */
|
---|
| 807 | {
|
---|
| 808 | struct redirect_header *redir_hdr;
|
---|
| 809 | struct lladdr_option *lladdr_opt;
|
---|
| 810 | ip6_addr_t destination_address, target_address;
|
---|
| 811 |
|
---|
| 812 | /* Check that Redir header fits in packet. */
|
---|
| 813 | if (p->len < sizeof(struct redirect_header)) {
|
---|
| 814 | /* @todo debug message */
|
---|
| 815 | pbuf_free(p);
|
---|
| 816 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 817 | ND6_STATS_INC(nd6.drop);
|
---|
| 818 | return;
|
---|
| 819 | }
|
---|
| 820 |
|
---|
| 821 | redir_hdr = (struct redirect_header *)p->payload;
|
---|
| 822 |
|
---|
| 823 | /* Create an aligned, zoned copy of the destination address. */
|
---|
| 824 | ip6_addr_copy_from_packed(destination_address, redir_hdr->destination_address);
|
---|
| 825 | ip6_addr_assign_zone(&destination_address, IP6_UNICAST, inp);
|
---|
| 826 |
|
---|
| 827 | /* Check a subset of the other RFC 4861 Sec. 8.1 requirements. */
|
---|
| 828 | if (!ip6_addr_islinklocal(ip6_current_src_addr()) ||
|
---|
| 829 | IP6H_HOPLIM(ip6_current_header()) != ND6_HOPLIM ||
|
---|
| 830 | redir_hdr->code != 0 || ip6_addr_ismulticast(&destination_address)) {
|
---|
| 831 | pbuf_free(p);
|
---|
| 832 | ND6_STATS_INC(nd6.proterr);
|
---|
| 833 | ND6_STATS_INC(nd6.drop);
|
---|
| 834 | return;
|
---|
| 835 | }
|
---|
| 836 |
|
---|
| 837 | /* @todo RFC MUST: IP source address equals first-hop router for destination_address */
|
---|
| 838 | /* @todo RFC MUST: ICMP target address is either link-local address or same as destination_address */
|
---|
| 839 | /* @todo RFC MUST: all included options have a length greater than zero */
|
---|
| 840 |
|
---|
| 841 | if (p->len >= (sizeof(struct redirect_header) + 2)) {
|
---|
| 842 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct redirect_header));
|
---|
| 843 | if (p->len < (sizeof(struct redirect_header) + (lladdr_opt->length << 3))) {
|
---|
| 844 | lladdr_opt = NULL;
|
---|
| 845 | }
|
---|
| 846 | } else {
|
---|
| 847 | lladdr_opt = NULL;
|
---|
| 848 | }
|
---|
| 849 |
|
---|
| 850 | /* Find dest address in cache */
|
---|
| 851 | dest_idx = nd6_find_destination_cache_entry(&destination_address);
|
---|
| 852 | if (dest_idx < 0) {
|
---|
| 853 | /* Destination not in cache, drop packet. */
|
---|
| 854 | pbuf_free(p);
|
---|
| 855 | return;
|
---|
| 856 | }
|
---|
| 857 |
|
---|
| 858 | /* Create an aligned, zoned copy of the target address. */
|
---|
| 859 | ip6_addr_copy_from_packed(target_address, redir_hdr->target_address);
|
---|
| 860 | ip6_addr_assign_zone(&target_address, IP6_UNICAST, inp);
|
---|
| 861 |
|
---|
| 862 | /* Set the new target address. */
|
---|
| 863 | ip6_addr_copy(destination_cache[dest_idx].next_hop_addr, target_address);
|
---|
| 864 |
|
---|
| 865 | /* If Link-layer address of other router is given, try to add to neighbor cache. */
|
---|
| 866 | if (lladdr_opt != NULL) {
|
---|
| 867 | if (lladdr_opt->type == ND6_OPTION_TYPE_TARGET_LLADDR) {
|
---|
| 868 | i = nd6_find_neighbor_cache_entry(&target_address);
|
---|
| 869 | if (i < 0) {
|
---|
| 870 | i = nd6_new_neighbor_cache_entry();
|
---|
| 871 | if (i >= 0) {
|
---|
| 872 | neighbor_cache[i].netif = inp;
|
---|
| 873 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 874 | ip6_addr_copy(neighbor_cache[i].next_hop_address, target_address);
|
---|
| 875 |
|
---|
| 876 | /* Receiving a message does not prove reachability: only in one direction.
|
---|
| 877 | * Delay probe in case we get confirmation of reachability from upper layer (TCP). */
|
---|
| 878 | neighbor_cache[i].state = ND6_DELAY;
|
---|
| 879 | neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
|
---|
| 880 | }
|
---|
| 881 | }
|
---|
| 882 | if (i >= 0) {
|
---|
| 883 | if (neighbor_cache[i].state == ND6_INCOMPLETE) {
|
---|
| 884 | MEMCPY(neighbor_cache[i].lladdr, lladdr_opt->addr, inp->hwaddr_len);
|
---|
| 885 | /* Receiving a message does not prove reachability: only in one direction.
|
---|
| 886 | * Delay probe in case we get confirmation of reachability from upper layer (TCP). */
|
---|
| 887 | neighbor_cache[i].state = ND6_DELAY;
|
---|
| 888 | neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
|
---|
| 889 | }
|
---|
| 890 | }
|
---|
| 891 | }
|
---|
| 892 | }
|
---|
| 893 | break; /* ICMP6_TYPE_RD */
|
---|
| 894 | }
|
---|
| 895 | case ICMP6_TYPE_PTB: /* Packet too big */
|
---|
| 896 | {
|
---|
| 897 | struct icmp6_hdr *icmp6hdr; /* Packet too big message */
|
---|
| 898 | struct ip6_hdr *ip6hdr; /* IPv6 header of the packet which caused the error */
|
---|
| 899 | u32_t pmtu;
|
---|
| 900 | ip6_addr_t destination_address;
|
---|
| 901 |
|
---|
| 902 | /* Check that ICMPv6 header + IPv6 header fit in payload */
|
---|
| 903 | if (p->len < (sizeof(struct icmp6_hdr) + IP6_HLEN)) {
|
---|
| 904 | /* drop short packets */
|
---|
| 905 | pbuf_free(p);
|
---|
| 906 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 907 | ND6_STATS_INC(nd6.drop);
|
---|
| 908 | return;
|
---|
| 909 | }
|
---|
| 910 |
|
---|
| 911 | icmp6hdr = (struct icmp6_hdr *)p->payload;
|
---|
| 912 | ip6hdr = (struct ip6_hdr *)((u8_t*)p->payload + sizeof(struct icmp6_hdr));
|
---|
| 913 |
|
---|
| 914 | /* Create an aligned, zoned copy of the destination address. */
|
---|
| 915 | ip6_addr_copy_from_packed(destination_address, ip6hdr->dest);
|
---|
| 916 | ip6_addr_assign_zone(&destination_address, IP6_UNKNOWN, inp);
|
---|
| 917 |
|
---|
| 918 | /* Look for entry in destination cache. */
|
---|
| 919 | dest_idx = nd6_find_destination_cache_entry(&destination_address);
|
---|
| 920 | if (dest_idx < 0) {
|
---|
| 921 | /* Destination not in cache, drop packet. */
|
---|
| 922 | pbuf_free(p);
|
---|
| 923 | return;
|
---|
| 924 | }
|
---|
| 925 |
|
---|
| 926 | /* Change the Path MTU. */
|
---|
| 927 | pmtu = lwip_htonl(icmp6hdr->data);
|
---|
| 928 | destination_cache[dest_idx].pmtu = (u16_t)LWIP_MIN(pmtu, 0xFFFF);
|
---|
| 929 |
|
---|
| 930 | break; /* ICMP6_TYPE_PTB */
|
---|
| 931 | }
|
---|
| 932 |
|
---|
| 933 | default:
|
---|
| 934 | ND6_STATS_INC(nd6.proterr);
|
---|
| 935 | ND6_STATS_INC(nd6.drop);
|
---|
| 936 | break; /* default */
|
---|
| 937 | }
|
---|
| 938 |
|
---|
| 939 | pbuf_free(p);
|
---|
| 940 | return;
|
---|
| 941 | lenerr_drop_free_return:
|
---|
| 942 | ND6_STATS_INC(nd6.lenerr);
|
---|
| 943 | ND6_STATS_INC(nd6.drop);
|
---|
| 944 | pbuf_free(p);
|
---|
| 945 | }
|
---|
| 946 |
|
---|
| 947 |
|
---|
| 948 | /**
|
---|
| 949 | * Periodic timer for Neighbor discovery functions:
|
---|
| 950 | *
|
---|
| 951 | * - Update neighbor reachability states
|
---|
| 952 | * - Update destination cache entries age
|
---|
| 953 | * - Update invalidation timers of default routers and on-link prefixes
|
---|
| 954 | * - Update lifetimes of our addresses
|
---|
| 955 | * - Perform duplicate address detection (DAD) for our addresses
|
---|
| 956 | * - Send router solicitations
|
---|
| 957 | */
|
---|
| 958 | void
|
---|
| 959 | nd6_tmr(void)
|
---|
| 960 | {
|
---|
| 961 | s8_t i;
|
---|
| 962 | struct netif *netif;
|
---|
| 963 |
|
---|
| 964 | /* Process neighbor entries. */
|
---|
| 965 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 966 | switch (neighbor_cache[i].state) {
|
---|
| 967 | case ND6_INCOMPLETE:
|
---|
| 968 | if ((neighbor_cache[i].counter.probes_sent >= LWIP_ND6_MAX_MULTICAST_SOLICIT) &&
|
---|
| 969 | (!neighbor_cache[i].isrouter)) {
|
---|
| 970 | /* Retries exceeded. */
|
---|
| 971 | nd6_free_neighbor_cache_entry(i);
|
---|
| 972 | } else {
|
---|
| 973 | /* Send a NS for this entry. */
|
---|
| 974 | neighbor_cache[i].counter.probes_sent++;
|
---|
| 975 | nd6_send_neighbor_cache_probe(&neighbor_cache[i], ND6_SEND_FLAG_MULTICAST_DEST);
|
---|
| 976 | }
|
---|
| 977 | break;
|
---|
| 978 | case ND6_REACHABLE:
|
---|
| 979 | /* Send queued packets, if any are left. Should have been sent already. */
|
---|
| 980 | if (neighbor_cache[i].q != NULL) {
|
---|
| 981 | nd6_send_q(i);
|
---|
| 982 | }
|
---|
| 983 | if (neighbor_cache[i].counter.reachable_time <= ND6_TMR_INTERVAL) {
|
---|
| 984 | /* Change to stale state. */
|
---|
| 985 | neighbor_cache[i].state = ND6_STALE;
|
---|
| 986 | neighbor_cache[i].counter.stale_time = 0;
|
---|
| 987 | } else {
|
---|
| 988 | neighbor_cache[i].counter.reachable_time -= ND6_TMR_INTERVAL;
|
---|
| 989 | }
|
---|
| 990 | break;
|
---|
| 991 | case ND6_STALE:
|
---|
| 992 | neighbor_cache[i].counter.stale_time++;
|
---|
| 993 | break;
|
---|
| 994 | case ND6_DELAY:
|
---|
| 995 | if (neighbor_cache[i].counter.delay_time <= 1) {
|
---|
| 996 | /* Change to PROBE state. */
|
---|
| 997 | neighbor_cache[i].state = ND6_PROBE;
|
---|
| 998 | neighbor_cache[i].counter.probes_sent = 0;
|
---|
| 999 | } else {
|
---|
| 1000 | neighbor_cache[i].counter.delay_time--;
|
---|
| 1001 | }
|
---|
| 1002 | break;
|
---|
| 1003 | case ND6_PROBE:
|
---|
| 1004 | if ((neighbor_cache[i].counter.probes_sent >= LWIP_ND6_MAX_MULTICAST_SOLICIT) &&
|
---|
| 1005 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1006 | /* Retries exceeded. */
|
---|
| 1007 | nd6_free_neighbor_cache_entry(i);
|
---|
| 1008 | } else {
|
---|
| 1009 | /* Send a NS for this entry. */
|
---|
| 1010 | neighbor_cache[i].counter.probes_sent++;
|
---|
| 1011 | nd6_send_neighbor_cache_probe(&neighbor_cache[i], 0);
|
---|
| 1012 | }
|
---|
| 1013 | break;
|
---|
| 1014 | case ND6_NO_ENTRY:
|
---|
| 1015 | default:
|
---|
| 1016 | /* Do nothing. */
|
---|
| 1017 | break;
|
---|
| 1018 | }
|
---|
| 1019 | }
|
---|
| 1020 |
|
---|
| 1021 | /* Process destination entries. */
|
---|
| 1022 | for (i = 0; i < LWIP_ND6_NUM_DESTINATIONS; i++) {
|
---|
| 1023 | destination_cache[i].age++;
|
---|
| 1024 | }
|
---|
| 1025 |
|
---|
| 1026 | /* Process router entries. */
|
---|
| 1027 | for (i = 0; i < LWIP_ND6_NUM_ROUTERS; i++) {
|
---|
| 1028 | if (default_router_list[i].neighbor_entry != NULL) {
|
---|
| 1029 | /* Active entry. */
|
---|
| 1030 | if (default_router_list[i].invalidation_timer <= ND6_TMR_INTERVAL / 1000) {
|
---|
| 1031 | /* No more than 1 second remaining. Clear this entry. Also clear any of
|
---|
| 1032 | * its destination cache entries, as per RFC 4861 Sec. 5.3 and 6.3.5. */
|
---|
| 1033 | s8_t j;
|
---|
| 1034 | for (j = 0; j < LWIP_ND6_NUM_DESTINATIONS; j++) {
|
---|
| 1035 | if (ip6_addr_cmp(&destination_cache[j].next_hop_addr,
|
---|
| 1036 | &default_router_list[i].neighbor_entry->next_hop_address)) {
|
---|
| 1037 | ip6_addr_set_any(&destination_cache[j].destination_addr);
|
---|
| 1038 | }
|
---|
| 1039 | }
|
---|
| 1040 | default_router_list[i].neighbor_entry->isrouter = 0;
|
---|
| 1041 | default_router_list[i].neighbor_entry = NULL;
|
---|
| 1042 | default_router_list[i].invalidation_timer = 0;
|
---|
| 1043 | default_router_list[i].flags = 0;
|
---|
| 1044 | } else {
|
---|
| 1045 | default_router_list[i].invalidation_timer -= ND6_TMR_INTERVAL / 1000;
|
---|
| 1046 | }
|
---|
| 1047 | }
|
---|
| 1048 | }
|
---|
| 1049 |
|
---|
| 1050 | /* Process prefix entries. */
|
---|
| 1051 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; i++) {
|
---|
| 1052 | if (prefix_list[i].netif != NULL) {
|
---|
| 1053 | if (prefix_list[i].invalidation_timer <= ND6_TMR_INTERVAL / 1000) {
|
---|
| 1054 | /* Entry timed out, remove it */
|
---|
| 1055 | prefix_list[i].invalidation_timer = 0;
|
---|
| 1056 | prefix_list[i].netif = NULL;
|
---|
| 1057 | } else {
|
---|
| 1058 | prefix_list[i].invalidation_timer -= ND6_TMR_INTERVAL / 1000;
|
---|
| 1059 | }
|
---|
| 1060 | }
|
---|
| 1061 | }
|
---|
| 1062 |
|
---|
| 1063 | /* Process our own addresses, updating address lifetimes and/or DAD state. */
|
---|
| 1064 | NETIF_FOREACH(netif) {
|
---|
| 1065 | for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
|
---|
| 1066 | u8_t addr_state;
|
---|
| 1067 | #if LWIP_IPV6_ADDRESS_LIFETIMES
|
---|
| 1068 | /* Step 1: update address lifetimes (valid and preferred). */
|
---|
| 1069 | addr_state = netif_ip6_addr_state(netif, i);
|
---|
| 1070 | /* RFC 4862 is not entirely clear as to whether address lifetimes affect
|
---|
| 1071 | * tentative addresses, and is even less clear as to what should happen
|
---|
| 1072 | * with duplicate addresses. We choose to track and update lifetimes for
|
---|
| 1073 | * both those types, although for different reasons:
|
---|
| 1074 | * - for tentative addresses, the line of thought of Sec. 5.7 combined
|
---|
| 1075 | * with the potentially long period that an address may be in tentative
|
---|
| 1076 | * state (due to the interface being down) suggests that lifetimes
|
---|
| 1077 | * should be independent of external factors which would include DAD;
|
---|
| 1078 | * - for duplicate addresses, retiring them early could result in a new
|
---|
| 1079 | * but unwanted attempt at marking them as valid, while retiring them
|
---|
| 1080 | * late/never could clog up address slots on the netif.
|
---|
| 1081 | * As a result, we may end up expiring addresses of either type here.
|
---|
| 1082 | */
|
---|
| 1083 | if (!ip6_addr_isinvalid(addr_state) &&
|
---|
| 1084 | !netif_ip6_addr_isstatic(netif, i)) {
|
---|
| 1085 | u32_t life = netif_ip6_addr_valid_life(netif, i);
|
---|
| 1086 | if (life <= ND6_TMR_INTERVAL / 1000) {
|
---|
| 1087 | /* The address has expired. */
|
---|
| 1088 | netif_ip6_addr_set_valid_life(netif, i, 0);
|
---|
| 1089 | netif_ip6_addr_set_pref_life(netif, i, 0);
|
---|
| 1090 | netif_ip6_addr_set_state(netif, i, IP6_ADDR_INVALID);
|
---|
| 1091 | } else {
|
---|
| 1092 | if (!ip6_addr_life_isinfinite(life)) {
|
---|
| 1093 | life -= ND6_TMR_INTERVAL / 1000;
|
---|
| 1094 | LWIP_ASSERT("bad valid lifetime", life != IP6_ADDR_LIFE_STATIC);
|
---|
| 1095 | netif_ip6_addr_set_valid_life(netif, i, life);
|
---|
| 1096 | }
|
---|
| 1097 | /* The address is still here. Update the preferred lifetime too. */
|
---|
| 1098 | life = netif_ip6_addr_pref_life(netif, i);
|
---|
| 1099 | if (life <= ND6_TMR_INTERVAL / 1000) {
|
---|
| 1100 | /* This case must also trigger if 'life' was already zero, so as to
|
---|
| 1101 | * deal correctly with advertised preferred-lifetime reductions. */
|
---|
| 1102 | netif_ip6_addr_set_pref_life(netif, i, 0);
|
---|
| 1103 | if (addr_state == IP6_ADDR_PREFERRED)
|
---|
| 1104 | netif_ip6_addr_set_state(netif, i, IP6_ADDR_DEPRECATED);
|
---|
| 1105 | } else if (!ip6_addr_life_isinfinite(life)) {
|
---|
| 1106 | life -= ND6_TMR_INTERVAL / 1000;
|
---|
| 1107 | netif_ip6_addr_set_pref_life(netif, i, life);
|
---|
| 1108 | }
|
---|
| 1109 | }
|
---|
| 1110 | }
|
---|
| 1111 | /* The address state may now have changed, so reobtain it next. */
|
---|
| 1112 | #endif /* LWIP_IPV6_ADDRESS_LIFETIMES */
|
---|
| 1113 | /* Step 2: update DAD state. */
|
---|
| 1114 | addr_state = netif_ip6_addr_state(netif, i);
|
---|
| 1115 | if (ip6_addr_istentative(addr_state)) {
|
---|
| 1116 | if ((addr_state & IP6_ADDR_TENTATIVE_COUNT_MASK) >= LWIP_IPV6_DUP_DETECT_ATTEMPTS) {
|
---|
| 1117 | /* No NA received in response. Mark address as valid. For dynamic
|
---|
| 1118 | * addresses with an expired preferred lifetime, the state is set to
|
---|
| 1119 | * deprecated right away. That should almost never happen, though. */
|
---|
| 1120 | addr_state = IP6_ADDR_PREFERRED;
|
---|
| 1121 | #if LWIP_IPV6_ADDRESS_LIFETIMES
|
---|
| 1122 | if (!netif_ip6_addr_isstatic(netif, i) &&
|
---|
| 1123 | netif_ip6_addr_pref_life(netif, i) == 0) {
|
---|
| 1124 | addr_state = IP6_ADDR_DEPRECATED;
|
---|
| 1125 | }
|
---|
| 1126 | #endif /* LWIP_IPV6_ADDRESS_LIFETIMES */
|
---|
| 1127 | netif_ip6_addr_set_state(netif, i, addr_state);
|
---|
| 1128 | } else if (netif_is_up(netif) && netif_is_link_up(netif)) {
|
---|
| 1129 | /* tentative: set next state by increasing by one */
|
---|
| 1130 | netif_ip6_addr_set_state(netif, i, addr_state + 1);
|
---|
| 1131 | /* Send a NS for this address. Use the unspecified address as source
|
---|
| 1132 | * address in all cases (RFC 4862 Sec. 5.4.2), not in the least
|
---|
| 1133 | * because as it is, we only consider multicast replies for DAD. */
|
---|
| 1134 | nd6_send_ns(netif, netif_ip6_addr(netif, i),
|
---|
| 1135 | ND6_SEND_FLAG_MULTICAST_DEST | ND6_SEND_FLAG_ANY_SRC);
|
---|
| 1136 | }
|
---|
| 1137 | }
|
---|
| 1138 | }
|
---|
| 1139 | }
|
---|
| 1140 |
|
---|
| 1141 | #if LWIP_IPV6_SEND_ROUTER_SOLICIT
|
---|
| 1142 | /* Send router solicitation messages, if necessary. */
|
---|
| 1143 | if (!nd6_tmr_rs_reduction) {
|
---|
| 1144 | nd6_tmr_rs_reduction = (ND6_RTR_SOLICITATION_INTERVAL / ND6_TMR_INTERVAL) - 1;
|
---|
| 1145 | NETIF_FOREACH(netif) {
|
---|
| 1146 | if ((netif->rs_count > 0) && netif_is_up(netif) &&
|
---|
| 1147 | netif_is_link_up(netif) &&
|
---|
| 1148 | !ip6_addr_isinvalid(netif_ip6_addr_state(netif, 0)) &&
|
---|
| 1149 | !ip6_addr_isduplicated(netif_ip6_addr_state(netif, 0))) {
|
---|
| 1150 | if (nd6_send_rs(netif) == ERR_OK) {
|
---|
| 1151 | netif->rs_count--;
|
---|
| 1152 | }
|
---|
| 1153 | }
|
---|
| 1154 | }
|
---|
| 1155 | } else {
|
---|
| 1156 | nd6_tmr_rs_reduction--;
|
---|
| 1157 | }
|
---|
| 1158 | #endif /* LWIP_IPV6_SEND_ROUTER_SOLICIT */
|
---|
| 1159 |
|
---|
| 1160 | }
|
---|
| 1161 |
|
---|
| 1162 | /** Send a neighbor solicitation message for a specific neighbor cache entry
|
---|
| 1163 | *
|
---|
| 1164 | * @param entry the neightbor cache entry for wich to send the message
|
---|
| 1165 | * @param flags one of ND6_SEND_FLAG_*
|
---|
| 1166 | */
|
---|
| 1167 | static void
|
---|
| 1168 | nd6_send_neighbor_cache_probe(struct nd6_neighbor_cache_entry *entry, u8_t flags)
|
---|
| 1169 | {
|
---|
| 1170 | nd6_send_ns(entry->netif, &entry->next_hop_address, flags);
|
---|
| 1171 | }
|
---|
| 1172 |
|
---|
| 1173 | /**
|
---|
| 1174 | * Send a neighbor solicitation message
|
---|
| 1175 | *
|
---|
| 1176 | * @param netif the netif on which to send the message
|
---|
| 1177 | * @param target_addr the IPv6 target address for the ND message
|
---|
| 1178 | * @param flags one of ND6_SEND_FLAG_*
|
---|
| 1179 | */
|
---|
| 1180 | static void
|
---|
| 1181 | nd6_send_ns(struct netif *netif, const ip6_addr_t *target_addr, u8_t flags)
|
---|
| 1182 | {
|
---|
| 1183 | struct ns_header *ns_hdr;
|
---|
| 1184 | struct pbuf *p;
|
---|
| 1185 | const ip6_addr_t *src_addr;
|
---|
| 1186 | u16_t lladdr_opt_len;
|
---|
| 1187 |
|
---|
| 1188 | LWIP_ASSERT("target address is required", target_addr != NULL);
|
---|
| 1189 |
|
---|
| 1190 | if (!(flags & ND6_SEND_FLAG_ANY_SRC) &&
|
---|
| 1191 | ip6_addr_isvalid(netif_ip6_addr_state(netif,0))) {
|
---|
| 1192 | /* Use link-local address as source address. */
|
---|
| 1193 | src_addr = netif_ip6_addr(netif, 0);
|
---|
| 1194 | /* calculate option length (in 8-byte-blocks) */
|
---|
| 1195 | lladdr_opt_len = ((netif->hwaddr_len + 2) + 7) >> 3;
|
---|
| 1196 | } else {
|
---|
| 1197 | src_addr = IP6_ADDR_ANY6;
|
---|
| 1198 | /* Option "MUST NOT be included when the source IP address is the unspecified address." */
|
---|
| 1199 | lladdr_opt_len = 0;
|
---|
| 1200 | }
|
---|
| 1201 |
|
---|
| 1202 | /* Allocate a packet. */
|
---|
| 1203 | p = pbuf_alloc(PBUF_IP, sizeof(struct ns_header) + (lladdr_opt_len << 3), PBUF_RAM);
|
---|
| 1204 | if (p == NULL) {
|
---|
| 1205 | ND6_STATS_INC(nd6.memerr);
|
---|
| 1206 | return;
|
---|
| 1207 | }
|
---|
| 1208 |
|
---|
| 1209 | /* Set fields. */
|
---|
| 1210 | ns_hdr = (struct ns_header *)p->payload;
|
---|
| 1211 |
|
---|
| 1212 | ns_hdr->type = ICMP6_TYPE_NS;
|
---|
| 1213 | ns_hdr->code = 0;
|
---|
| 1214 | ns_hdr->chksum = 0;
|
---|
| 1215 | ns_hdr->reserved = 0;
|
---|
| 1216 | ip6_addr_copy_to_packed(ns_hdr->target_address, *target_addr);
|
---|
| 1217 |
|
---|
| 1218 | if (lladdr_opt_len != 0) {
|
---|
| 1219 | struct lladdr_option *lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct ns_header));
|
---|
| 1220 | lladdr_opt->type = ND6_OPTION_TYPE_SOURCE_LLADDR;
|
---|
| 1221 | lladdr_opt->length = (u8_t)lladdr_opt_len;
|
---|
| 1222 | SMEMCPY(lladdr_opt->addr, netif->hwaddr, netif->hwaddr_len);
|
---|
| 1223 | }
|
---|
| 1224 |
|
---|
| 1225 | /* Generate the solicited node address for the target address. */
|
---|
| 1226 | if (flags & ND6_SEND_FLAG_MULTICAST_DEST) {
|
---|
| 1227 | ip6_addr_set_solicitednode(&multicast_address, target_addr->addr[3]);
|
---|
| 1228 | ip6_addr_assign_zone(&multicast_address, IP6_MULTICAST, netif);
|
---|
| 1229 | target_addr = &multicast_address;
|
---|
| 1230 | }
|
---|
| 1231 |
|
---|
| 1232 | #if CHECKSUM_GEN_ICMP6
|
---|
| 1233 | IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_ICMP6) {
|
---|
| 1234 | ns_hdr->chksum = ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->len, src_addr,
|
---|
| 1235 | target_addr);
|
---|
| 1236 | }
|
---|
| 1237 | #endif /* CHECKSUM_GEN_ICMP6 */
|
---|
| 1238 |
|
---|
| 1239 | /* Send the packet out. */
|
---|
| 1240 | ND6_STATS_INC(nd6.xmit);
|
---|
| 1241 | ip6_output_if(p, (src_addr == IP6_ADDR_ANY6) ? NULL : src_addr, target_addr,
|
---|
| 1242 | ND6_HOPLIM, 0, IP6_NEXTH_ICMP6, netif);
|
---|
| 1243 | pbuf_free(p);
|
---|
| 1244 | }
|
---|
| 1245 |
|
---|
| 1246 | /**
|
---|
| 1247 | * Send a neighbor advertisement message
|
---|
| 1248 | *
|
---|
| 1249 | * @param netif the netif on which to send the message
|
---|
| 1250 | * @param target_addr the IPv6 target address for the ND message
|
---|
| 1251 | * @param flags one of ND6_SEND_FLAG_*
|
---|
| 1252 | */
|
---|
| 1253 | static void
|
---|
| 1254 | nd6_send_na(struct netif *netif, const ip6_addr_t *target_addr, u8_t flags)
|
---|
| 1255 | {
|
---|
| 1256 | struct na_header *na_hdr;
|
---|
| 1257 | struct lladdr_option *lladdr_opt;
|
---|
| 1258 | struct pbuf *p;
|
---|
| 1259 | const ip6_addr_t *src_addr;
|
---|
| 1260 | const ip6_addr_t *dest_addr;
|
---|
| 1261 | u16_t lladdr_opt_len;
|
---|
| 1262 |
|
---|
| 1263 | LWIP_ASSERT("target address is required", target_addr != NULL);
|
---|
| 1264 |
|
---|
| 1265 | /* Use link-local address as source address. */
|
---|
| 1266 | /* src_addr = netif_ip6_addr(netif, 0); */
|
---|
| 1267 | /* Use target address as source address. */
|
---|
| 1268 | src_addr = target_addr;
|
---|
| 1269 |
|
---|
| 1270 | /* Allocate a packet. */
|
---|
| 1271 | lladdr_opt_len = ((netif->hwaddr_len + 2) >> 3) + (((netif->hwaddr_len + 2) & 0x07) ? 1 : 0);
|
---|
| 1272 | p = pbuf_alloc(PBUF_IP, sizeof(struct na_header) + (lladdr_opt_len << 3), PBUF_RAM);
|
---|
| 1273 | if (p == NULL) {
|
---|
| 1274 | ND6_STATS_INC(nd6.memerr);
|
---|
| 1275 | return;
|
---|
| 1276 | }
|
---|
| 1277 |
|
---|
| 1278 | /* Set fields. */
|
---|
| 1279 | na_hdr = (struct na_header *)p->payload;
|
---|
| 1280 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct na_header));
|
---|
| 1281 |
|
---|
| 1282 | na_hdr->type = ICMP6_TYPE_NA;
|
---|
| 1283 | na_hdr->code = 0;
|
---|
| 1284 | na_hdr->chksum = 0;
|
---|
| 1285 | na_hdr->flags = flags & 0xf0;
|
---|
| 1286 | na_hdr->reserved[0] = 0;
|
---|
| 1287 | na_hdr->reserved[1] = 0;
|
---|
| 1288 | na_hdr->reserved[2] = 0;
|
---|
| 1289 | ip6_addr_copy_to_packed(na_hdr->target_address, *target_addr);
|
---|
| 1290 |
|
---|
| 1291 | lladdr_opt->type = ND6_OPTION_TYPE_TARGET_LLADDR;
|
---|
| 1292 | lladdr_opt->length = (u8_t)lladdr_opt_len;
|
---|
| 1293 | SMEMCPY(lladdr_opt->addr, netif->hwaddr, netif->hwaddr_len);
|
---|
| 1294 |
|
---|
| 1295 | /* Generate the solicited node address for the target address. */
|
---|
| 1296 | if (flags & ND6_SEND_FLAG_MULTICAST_DEST) {
|
---|
| 1297 | ip6_addr_set_solicitednode(&multicast_address, target_addr->addr[3]);
|
---|
| 1298 | ip6_addr_assign_zone(&multicast_address, IP6_MULTICAST, netif);
|
---|
| 1299 | dest_addr = &multicast_address;
|
---|
| 1300 | } else if (flags & ND6_SEND_FLAG_ALLNODES_DEST) {
|
---|
| 1301 | ip6_addr_set_allnodes_linklocal(&multicast_address);
|
---|
| 1302 | ip6_addr_assign_zone(&multicast_address, IP6_MULTICAST, netif);
|
---|
| 1303 | dest_addr = &multicast_address;
|
---|
| 1304 | } else {
|
---|
| 1305 | dest_addr = ip6_current_src_addr();
|
---|
| 1306 | }
|
---|
| 1307 |
|
---|
| 1308 | #if CHECKSUM_GEN_ICMP6
|
---|
| 1309 | IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_ICMP6) {
|
---|
| 1310 | na_hdr->chksum = ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->len, src_addr,
|
---|
| 1311 | dest_addr);
|
---|
| 1312 | }
|
---|
| 1313 | #endif /* CHECKSUM_GEN_ICMP6 */
|
---|
| 1314 |
|
---|
| 1315 | /* Send the packet out. */
|
---|
| 1316 | ND6_STATS_INC(nd6.xmit);
|
---|
| 1317 | ip6_output_if(p, src_addr, dest_addr,
|
---|
| 1318 | ND6_HOPLIM, 0, IP6_NEXTH_ICMP6, netif);
|
---|
| 1319 | pbuf_free(p);
|
---|
| 1320 | }
|
---|
| 1321 |
|
---|
| 1322 | #if LWIP_IPV6_SEND_ROUTER_SOLICIT
|
---|
| 1323 | /**
|
---|
| 1324 | * Send a router solicitation message
|
---|
| 1325 | *
|
---|
| 1326 | * @param netif the netif on which to send the message
|
---|
| 1327 | */
|
---|
| 1328 | static err_t
|
---|
| 1329 | nd6_send_rs(struct netif *netif)
|
---|
| 1330 | {
|
---|
| 1331 | struct rs_header *rs_hdr;
|
---|
| 1332 | struct lladdr_option *lladdr_opt;
|
---|
| 1333 | struct pbuf *p;
|
---|
| 1334 | const ip6_addr_t *src_addr;
|
---|
| 1335 | err_t err;
|
---|
| 1336 | u16_t lladdr_opt_len = 0;
|
---|
| 1337 |
|
---|
| 1338 | /* Link-local source address, or unspecified address? */
|
---|
| 1339 | if (ip6_addr_isvalid(netif_ip6_addr_state(netif, 0))) {
|
---|
| 1340 | src_addr = netif_ip6_addr(netif, 0);
|
---|
| 1341 | } else {
|
---|
| 1342 | src_addr = IP6_ADDR_ANY6;
|
---|
| 1343 | }
|
---|
| 1344 |
|
---|
| 1345 | /* Generate the all routers target address. */
|
---|
| 1346 | ip6_addr_set_allrouters_linklocal(&multicast_address);
|
---|
| 1347 | ip6_addr_assign_zone(&multicast_address, IP6_MULTICAST, netif);
|
---|
| 1348 |
|
---|
| 1349 | /* Allocate a packet. */
|
---|
| 1350 | if (src_addr != IP6_ADDR_ANY6) {
|
---|
| 1351 | lladdr_opt_len = ((netif->hwaddr_len + 2) >> 3) + (((netif->hwaddr_len + 2) & 0x07) ? 1 : 0);
|
---|
| 1352 | }
|
---|
| 1353 | p = pbuf_alloc(PBUF_IP, sizeof(struct rs_header) + (lladdr_opt_len << 3), PBUF_RAM);
|
---|
| 1354 | if (p == NULL) {
|
---|
| 1355 | ND6_STATS_INC(nd6.memerr);
|
---|
| 1356 | return ERR_BUF;
|
---|
| 1357 | }
|
---|
| 1358 |
|
---|
| 1359 | /* Set fields. */
|
---|
| 1360 | rs_hdr = (struct rs_header *)p->payload;
|
---|
| 1361 |
|
---|
| 1362 | rs_hdr->type = ICMP6_TYPE_RS;
|
---|
| 1363 | rs_hdr->code = 0;
|
---|
| 1364 | rs_hdr->chksum = 0;
|
---|
| 1365 | rs_hdr->reserved = 0;
|
---|
| 1366 |
|
---|
| 1367 | if (src_addr != IP6_ADDR_ANY6) {
|
---|
| 1368 | /* Include our hw address. */
|
---|
| 1369 | lladdr_opt = (struct lladdr_option *)((u8_t*)p->payload + sizeof(struct rs_header));
|
---|
| 1370 | lladdr_opt->type = ND6_OPTION_TYPE_SOURCE_LLADDR;
|
---|
| 1371 | lladdr_opt->length = (u8_t)lladdr_opt_len;
|
---|
| 1372 | SMEMCPY(lladdr_opt->addr, netif->hwaddr, netif->hwaddr_len);
|
---|
| 1373 | }
|
---|
| 1374 |
|
---|
| 1375 | #if CHECKSUM_GEN_ICMP6
|
---|
| 1376 | IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_ICMP6) {
|
---|
| 1377 | rs_hdr->chksum = ip6_chksum_pseudo(p, IP6_NEXTH_ICMP6, p->len, src_addr,
|
---|
| 1378 | &multicast_address);
|
---|
| 1379 | }
|
---|
| 1380 | #endif /* CHECKSUM_GEN_ICMP6 */
|
---|
| 1381 |
|
---|
| 1382 | /* Send the packet out. */
|
---|
| 1383 | ND6_STATS_INC(nd6.xmit);
|
---|
| 1384 |
|
---|
| 1385 | err = ip6_output_if(p, (src_addr == IP6_ADDR_ANY6) ? NULL : src_addr, &multicast_address,
|
---|
| 1386 | ND6_HOPLIM, 0, IP6_NEXTH_ICMP6, netif);
|
---|
| 1387 | pbuf_free(p);
|
---|
| 1388 |
|
---|
| 1389 | return err;
|
---|
| 1390 | }
|
---|
| 1391 | #endif /* LWIP_IPV6_SEND_ROUTER_SOLICIT */
|
---|
| 1392 |
|
---|
| 1393 | /**
|
---|
| 1394 | * Search for a neighbor cache entry
|
---|
| 1395 | *
|
---|
| 1396 | * @param ip6addr the IPv6 address of the neighbor
|
---|
| 1397 | * @return The neighbor cache entry index that matched, -1 if no
|
---|
| 1398 | * entry is found
|
---|
| 1399 | */
|
---|
| 1400 | static s8_t
|
---|
| 1401 | nd6_find_neighbor_cache_entry(const ip6_addr_t *ip6addr)
|
---|
| 1402 | {
|
---|
| 1403 | s8_t i;
|
---|
| 1404 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1405 | if (ip6_addr_cmp(ip6addr, &(neighbor_cache[i].next_hop_address))) {
|
---|
| 1406 | return i;
|
---|
| 1407 | }
|
---|
| 1408 | }
|
---|
| 1409 | return -1;
|
---|
| 1410 | }
|
---|
| 1411 |
|
---|
| 1412 | /**
|
---|
| 1413 | * Create a new neighbor cache entry.
|
---|
| 1414 | *
|
---|
| 1415 | * If no unused entry is found, will try to recycle an old entry
|
---|
| 1416 | * according to ad-hoc "age" heuristic.
|
---|
| 1417 | *
|
---|
| 1418 | * @return The neighbor cache entry index that was created, -1 if no
|
---|
| 1419 | * entry could be created
|
---|
| 1420 | */
|
---|
| 1421 | static s8_t
|
---|
| 1422 | nd6_new_neighbor_cache_entry(void)
|
---|
| 1423 | {
|
---|
| 1424 | s8_t i;
|
---|
| 1425 | s8_t j;
|
---|
| 1426 | u32_t time;
|
---|
| 1427 |
|
---|
| 1428 |
|
---|
| 1429 | /* First, try to find an empty entry. */
|
---|
| 1430 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1431 | if (neighbor_cache[i].state == ND6_NO_ENTRY) {
|
---|
| 1432 | return i;
|
---|
| 1433 | }
|
---|
| 1434 | }
|
---|
| 1435 |
|
---|
| 1436 | /* We need to recycle an entry. in general, do not recycle if it is a router. */
|
---|
| 1437 |
|
---|
| 1438 | /* Next, try to find a Stale entry. */
|
---|
| 1439 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1440 | if ((neighbor_cache[i].state == ND6_STALE) &&
|
---|
| 1441 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1442 | nd6_free_neighbor_cache_entry(i);
|
---|
| 1443 | return i;
|
---|
| 1444 | }
|
---|
| 1445 | }
|
---|
| 1446 |
|
---|
| 1447 | /* Next, try to find a Probe entry. */
|
---|
| 1448 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1449 | if ((neighbor_cache[i].state == ND6_PROBE) &&
|
---|
| 1450 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1451 | nd6_free_neighbor_cache_entry(i);
|
---|
| 1452 | return i;
|
---|
| 1453 | }
|
---|
| 1454 | }
|
---|
| 1455 |
|
---|
| 1456 | /* Next, try to find a Delayed entry. */
|
---|
| 1457 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1458 | if ((neighbor_cache[i].state == ND6_DELAY) &&
|
---|
| 1459 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1460 | nd6_free_neighbor_cache_entry(i);
|
---|
| 1461 | return i;
|
---|
| 1462 | }
|
---|
| 1463 | }
|
---|
| 1464 |
|
---|
| 1465 | /* Next, try to find the oldest reachable entry. */
|
---|
| 1466 | time = 0xfffffffful;
|
---|
| 1467 | j = -1;
|
---|
| 1468 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1469 | if ((neighbor_cache[i].state == ND6_REACHABLE) &&
|
---|
| 1470 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1471 | if (neighbor_cache[i].counter.reachable_time < time) {
|
---|
| 1472 | j = i;
|
---|
| 1473 | time = neighbor_cache[i].counter.reachable_time;
|
---|
| 1474 | }
|
---|
| 1475 | }
|
---|
| 1476 | }
|
---|
| 1477 | if (j >= 0) {
|
---|
| 1478 | nd6_free_neighbor_cache_entry(j);
|
---|
| 1479 | return j;
|
---|
| 1480 | }
|
---|
| 1481 |
|
---|
| 1482 | /* Next, find oldest incomplete entry without queued packets. */
|
---|
| 1483 | time = 0;
|
---|
| 1484 | j = -1;
|
---|
| 1485 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1486 | if (
|
---|
| 1487 | (neighbor_cache[i].q == NULL) &&
|
---|
| 1488 | (neighbor_cache[i].state == ND6_INCOMPLETE) &&
|
---|
| 1489 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1490 | if (neighbor_cache[i].counter.probes_sent >= time) {
|
---|
| 1491 | j = i;
|
---|
| 1492 | time = neighbor_cache[i].counter.probes_sent;
|
---|
| 1493 | }
|
---|
| 1494 | }
|
---|
| 1495 | }
|
---|
| 1496 | if (j >= 0) {
|
---|
| 1497 | nd6_free_neighbor_cache_entry(j);
|
---|
| 1498 | return j;
|
---|
| 1499 | }
|
---|
| 1500 |
|
---|
| 1501 | /* Next, find oldest incomplete entry with queued packets. */
|
---|
| 1502 | time = 0;
|
---|
| 1503 | j = -1;
|
---|
| 1504 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 1505 | if ((neighbor_cache[i].state == ND6_INCOMPLETE) &&
|
---|
| 1506 | (!neighbor_cache[i].isrouter)) {
|
---|
| 1507 | if (neighbor_cache[i].counter.probes_sent >= time) {
|
---|
| 1508 | j = i;
|
---|
| 1509 | time = neighbor_cache[i].counter.probes_sent;
|
---|
| 1510 | }
|
---|
| 1511 | }
|
---|
| 1512 | }
|
---|
| 1513 | if (j >= 0) {
|
---|
| 1514 | nd6_free_neighbor_cache_entry(j);
|
---|
| 1515 | return j;
|
---|
| 1516 | }
|
---|
| 1517 |
|
---|
| 1518 | /* No more entries to try. */
|
---|
| 1519 | return -1;
|
---|
| 1520 | }
|
---|
| 1521 |
|
---|
| 1522 | /**
|
---|
| 1523 | * Will free any resources associated with a neighbor cache
|
---|
| 1524 | * entry, and will mark it as unused.
|
---|
| 1525 | *
|
---|
| 1526 | * @param i the neighbor cache entry index to free
|
---|
| 1527 | */
|
---|
| 1528 | static void
|
---|
| 1529 | nd6_free_neighbor_cache_entry(s8_t i)
|
---|
| 1530 | {
|
---|
| 1531 | if ((i < 0) || (i >= LWIP_ND6_NUM_NEIGHBORS)) {
|
---|
| 1532 | return;
|
---|
| 1533 | }
|
---|
| 1534 | if (neighbor_cache[i].isrouter) {
|
---|
| 1535 | /* isrouter needs to be cleared before deleting a neighbor cache entry */
|
---|
| 1536 | return;
|
---|
| 1537 | }
|
---|
| 1538 |
|
---|
| 1539 | /* Free any queued packets. */
|
---|
| 1540 | if (neighbor_cache[i].q != NULL) {
|
---|
| 1541 | nd6_free_q(neighbor_cache[i].q);
|
---|
| 1542 | neighbor_cache[i].q = NULL;
|
---|
| 1543 | }
|
---|
| 1544 |
|
---|
| 1545 | neighbor_cache[i].state = ND6_NO_ENTRY;
|
---|
| 1546 | neighbor_cache[i].isrouter = 0;
|
---|
| 1547 | neighbor_cache[i].netif = NULL;
|
---|
| 1548 | neighbor_cache[i].counter.reachable_time = 0;
|
---|
| 1549 | ip6_addr_set_zero(&(neighbor_cache[i].next_hop_address));
|
---|
| 1550 | }
|
---|
| 1551 |
|
---|
| 1552 | /**
|
---|
| 1553 | * Search for a destination cache entry
|
---|
| 1554 | *
|
---|
| 1555 | * @param ip6addr the IPv6 address of the destination
|
---|
| 1556 | * @return The destination cache entry index that matched, -1 if no
|
---|
| 1557 | * entry is found
|
---|
| 1558 | */
|
---|
| 1559 | static s16_t
|
---|
| 1560 | nd6_find_destination_cache_entry(const ip6_addr_t *ip6addr)
|
---|
| 1561 | {
|
---|
| 1562 | s16_t i;
|
---|
| 1563 |
|
---|
| 1564 | IP6_ADDR_ZONECHECK(ip6addr);
|
---|
| 1565 |
|
---|
| 1566 | for (i = 0; i < LWIP_ND6_NUM_DESTINATIONS; i++) {
|
---|
| 1567 | if (ip6_addr_cmp(ip6addr, &(destination_cache[i].destination_addr))) {
|
---|
| 1568 | return i;
|
---|
| 1569 | }
|
---|
| 1570 | }
|
---|
| 1571 | return -1;
|
---|
| 1572 | }
|
---|
| 1573 |
|
---|
| 1574 | /**
|
---|
| 1575 | * Create a new destination cache entry. If no unused entry is found,
|
---|
| 1576 | * will recycle oldest entry.
|
---|
| 1577 | *
|
---|
| 1578 | * @return The destination cache entry index that was created, -1 if no
|
---|
| 1579 | * entry was created
|
---|
| 1580 | */
|
---|
| 1581 | static s16_t
|
---|
| 1582 | nd6_new_destination_cache_entry(void)
|
---|
| 1583 | {
|
---|
| 1584 | s16_t i, j;
|
---|
| 1585 | u32_t age;
|
---|
| 1586 |
|
---|
| 1587 | /* Find an empty entry. */
|
---|
| 1588 | for (i = 0; i < LWIP_ND6_NUM_DESTINATIONS; i++) {
|
---|
| 1589 | if (ip6_addr_isany(&(destination_cache[i].destination_addr))) {
|
---|
| 1590 | return i;
|
---|
| 1591 | }
|
---|
| 1592 | }
|
---|
| 1593 |
|
---|
| 1594 | /* Find oldest entry. */
|
---|
| 1595 | age = 0;
|
---|
| 1596 | j = LWIP_ND6_NUM_DESTINATIONS - 1;
|
---|
| 1597 | for (i = 0; i < LWIP_ND6_NUM_DESTINATIONS; i++) {
|
---|
| 1598 | if (destination_cache[i].age > age) {
|
---|
| 1599 | j = i;
|
---|
| 1600 | }
|
---|
| 1601 | }
|
---|
| 1602 |
|
---|
| 1603 | return j;
|
---|
| 1604 | }
|
---|
| 1605 |
|
---|
| 1606 | /**
|
---|
| 1607 | * Clear the destination cache.
|
---|
| 1608 | *
|
---|
| 1609 | * This operation may be necessary for consistency in the light of changing
|
---|
| 1610 | * local addresses and/or use of the gateway hook.
|
---|
| 1611 | */
|
---|
| 1612 | void
|
---|
| 1613 | nd6_clear_destination_cache(void)
|
---|
| 1614 | {
|
---|
| 1615 | int i;
|
---|
| 1616 |
|
---|
| 1617 | for (i = 0; i < LWIP_ND6_NUM_DESTINATIONS; i++) {
|
---|
| 1618 | ip6_addr_set_any(&destination_cache[i].destination_addr);
|
---|
| 1619 | }
|
---|
| 1620 | }
|
---|
| 1621 |
|
---|
| 1622 | /**
|
---|
| 1623 | * Determine whether an address matches an on-link prefix or the subnet of a
|
---|
| 1624 | * statically assigned address.
|
---|
| 1625 | *
|
---|
| 1626 | * @param ip6addr the IPv6 address to match
|
---|
| 1627 | * @return 1 if the address is on-link, 0 otherwise
|
---|
| 1628 | */
|
---|
| 1629 | static int
|
---|
| 1630 | nd6_is_prefix_in_netif(const ip6_addr_t *ip6addr, struct netif *netif)
|
---|
| 1631 | {
|
---|
| 1632 | s8_t i;
|
---|
| 1633 |
|
---|
| 1634 | /* Check to see if the address matches an on-link prefix. */
|
---|
| 1635 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; i++) {
|
---|
| 1636 | if ((prefix_list[i].netif == netif) &&
|
---|
| 1637 | (prefix_list[i].invalidation_timer > 0) &&
|
---|
| 1638 | ip6_addr_netcmp(ip6addr, &(prefix_list[i].prefix))) {
|
---|
| 1639 | return 1;
|
---|
| 1640 | }
|
---|
| 1641 | }
|
---|
| 1642 | /* Check to see if address prefix matches a manually configured (= static)
|
---|
| 1643 | * address. Static addresses have an implied /64 subnet assignment. Dynamic
|
---|
| 1644 | * addresses (from autoconfiguration) have no implied subnet assignment, and
|
---|
| 1645 | * are thus effectively /128 assignments. See RFC 5942 for more on this. */
|
---|
| 1646 | for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
|
---|
| 1647 | if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
|
---|
| 1648 | netif_ip6_addr_isstatic(netif, i) &&
|
---|
| 1649 | ip6_addr_netcmp(ip6addr, netif_ip6_addr(netif, i))) {
|
---|
| 1650 | return 1;
|
---|
| 1651 | }
|
---|
| 1652 | }
|
---|
| 1653 | return 0;
|
---|
| 1654 | }
|
---|
| 1655 |
|
---|
| 1656 | /**
|
---|
| 1657 | * Select a default router for a destination.
|
---|
| 1658 | *
|
---|
| 1659 | * This function is used both for routing and for finding a next-hop target for
|
---|
| 1660 | * a packet. In the former case, the given netif is NULL, and the returned
|
---|
| 1661 | * router entry must be for a netif suitable for sending packets (up, link up).
|
---|
| 1662 | * In the latter case, the given netif is not NULL and restricts router choice.
|
---|
| 1663 | *
|
---|
| 1664 | * @param ip6addr the destination address
|
---|
| 1665 | * @param netif the netif for the outgoing packet, if known
|
---|
| 1666 | * @return the default router entry index, or -1 if no suitable
|
---|
| 1667 | * router is found
|
---|
| 1668 | */
|
---|
| 1669 | static s8_t
|
---|
| 1670 | nd6_select_router(const ip6_addr_t *ip6addr, struct netif *netif)
|
---|
| 1671 | {
|
---|
| 1672 | struct netif *router_netif;
|
---|
| 1673 | s8_t i, j, valid_router;
|
---|
| 1674 | static s8_t last_router;
|
---|
| 1675 |
|
---|
| 1676 | LWIP_UNUSED_ARG(ip6addr); /* @todo match preferred routes!! (must implement ND6_OPTION_TYPE_ROUTE_INFO) */
|
---|
| 1677 |
|
---|
| 1678 | /* @todo: implement default router preference */
|
---|
| 1679 |
|
---|
| 1680 | /* Look for valid routers. A reachable router is preferred. */
|
---|
| 1681 | valid_router = -1;
|
---|
| 1682 | for (i = 0; i < LWIP_ND6_NUM_ROUTERS; i++) {
|
---|
| 1683 | /* Is the router netif both set and apppropriate? */
|
---|
| 1684 | if (default_router_list[i].neighbor_entry != NULL) {
|
---|
| 1685 | router_netif = default_router_list[i].neighbor_entry->netif;
|
---|
| 1686 | if ((router_netif != NULL) && (netif != NULL ? netif == router_netif :
|
---|
| 1687 | (netif_is_up(router_netif) && netif_is_link_up(router_netif)))) {
|
---|
| 1688 | /* Is the router valid, i.e., reachable or probably reachable as per
|
---|
| 1689 | * RFC 4861 Sec. 6.3.6? Note that we will never return a router that
|
---|
| 1690 | * has no neighbor cache entry, due to the netif association tests. */
|
---|
| 1691 | if (default_router_list[i].neighbor_entry->state != ND6_INCOMPLETE) {
|
---|
| 1692 | /* Is the router known to be reachable? */
|
---|
| 1693 | if (default_router_list[i].neighbor_entry->state == ND6_REACHABLE) {
|
---|
| 1694 | return i; /* valid and reachable - done! */
|
---|
| 1695 | } else if (valid_router < 0) {
|
---|
| 1696 | valid_router = i; /* valid but not known to be reachable */
|
---|
| 1697 | }
|
---|
| 1698 | }
|
---|
| 1699 | }
|
---|
| 1700 | }
|
---|
| 1701 | }
|
---|
| 1702 | if (valid_router >= 0) {
|
---|
| 1703 | return valid_router;
|
---|
| 1704 | }
|
---|
| 1705 |
|
---|
| 1706 | /* Look for any router for which we have any information at all. */
|
---|
| 1707 | /* last_router is used for round-robin selection of incomplete routers, as
|
---|
| 1708 | * recommended in RFC 4861 Sec. 6.3.6 point (2). Advance only when picking a
|
---|
| 1709 | * route, to select the same router as next-hop target in the common case. */
|
---|
| 1710 | if ((netif == NULL) && (++last_router >= LWIP_ND6_NUM_ROUTERS)) {
|
---|
| 1711 | last_router = 0;
|
---|
| 1712 | }
|
---|
| 1713 | i = last_router;
|
---|
| 1714 | for (j = 0; j < LWIP_ND6_NUM_ROUTERS; j++) {
|
---|
| 1715 | if (default_router_list[i].neighbor_entry != NULL) {
|
---|
| 1716 | router_netif = default_router_list[i].neighbor_entry->netif;
|
---|
| 1717 | if ((router_netif != NULL) && (netif != NULL ? netif == router_netif :
|
---|
| 1718 | (netif_is_up(router_netif) && netif_is_link_up(router_netif)))) {
|
---|
| 1719 | return i;
|
---|
| 1720 | }
|
---|
| 1721 | }
|
---|
| 1722 | if (++i >= LWIP_ND6_NUM_ROUTERS) {
|
---|
| 1723 | i = 0;
|
---|
| 1724 | }
|
---|
| 1725 | }
|
---|
| 1726 |
|
---|
| 1727 | /* no suitable router found. */
|
---|
| 1728 | return -1;
|
---|
| 1729 | }
|
---|
| 1730 |
|
---|
| 1731 | /**
|
---|
| 1732 | * Find a router-announced route to the given destination. This route may be
|
---|
| 1733 | * based on an on-link prefix or a default router.
|
---|
| 1734 | *
|
---|
| 1735 | * If a suitable route is found, the returned netif is guaranteed to be in a
|
---|
| 1736 | * suitable state (up, link up) to be used for packet transmission.
|
---|
| 1737 | *
|
---|
| 1738 | * @param ip6addr the destination IPv6 address
|
---|
| 1739 | * @return the netif to use for the destination, or NULL if none found
|
---|
| 1740 | */
|
---|
| 1741 | struct netif *
|
---|
| 1742 | nd6_find_route(const ip6_addr_t *ip6addr)
|
---|
| 1743 | {
|
---|
| 1744 | struct netif *netif;
|
---|
| 1745 | s8_t i;
|
---|
| 1746 |
|
---|
| 1747 | /* @todo decide if it makes sense to check the destination cache first */
|
---|
| 1748 |
|
---|
| 1749 | /* Check if there is a matching on-link prefix. There may be multiple
|
---|
| 1750 | * matches. Pick the first one that is associated with a suitable netif. */
|
---|
| 1751 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; ++i) {
|
---|
| 1752 | netif = prefix_list[i].netif;
|
---|
| 1753 | if ((netif != NULL) && ip6_addr_netcmp(&prefix_list[i].prefix, ip6addr) &&
|
---|
| 1754 | netif_is_up(netif) && netif_is_link_up(netif)) {
|
---|
| 1755 | return netif;
|
---|
| 1756 | }
|
---|
| 1757 | }
|
---|
| 1758 |
|
---|
| 1759 | /* No on-link prefix match. Find a router that can forward the packet. */
|
---|
| 1760 | i = nd6_select_router(ip6addr, NULL);
|
---|
| 1761 | if (i >= 0) {
|
---|
| 1762 | LWIP_ASSERT("selected router must have a neighbor entry",
|
---|
| 1763 | default_router_list[i].neighbor_entry != NULL);
|
---|
| 1764 | return default_router_list[i].neighbor_entry->netif;
|
---|
| 1765 | }
|
---|
| 1766 |
|
---|
| 1767 | return NULL;
|
---|
| 1768 | }
|
---|
| 1769 |
|
---|
| 1770 | /**
|
---|
| 1771 | * Find an entry for a default router.
|
---|
| 1772 | *
|
---|
| 1773 | * @param router_addr the IPv6 address of the router
|
---|
| 1774 | * @param netif the netif on which the router is found, if known
|
---|
| 1775 | * @return the index of the router entry, or -1 if not found
|
---|
| 1776 | */
|
---|
| 1777 | static s8_t
|
---|
| 1778 | nd6_get_router(const ip6_addr_t *router_addr, struct netif *netif)
|
---|
| 1779 | {
|
---|
| 1780 | s8_t i;
|
---|
| 1781 |
|
---|
| 1782 | IP6_ADDR_ZONECHECK_NETIF(router_addr, netif);
|
---|
| 1783 |
|
---|
| 1784 | /* Look for router. */
|
---|
| 1785 | for (i = 0; i < LWIP_ND6_NUM_ROUTERS; i++) {
|
---|
| 1786 | if ((default_router_list[i].neighbor_entry != NULL) &&
|
---|
| 1787 | ((netif != NULL) ? netif == default_router_list[i].neighbor_entry->netif : 1) &&
|
---|
| 1788 | ip6_addr_cmp(router_addr, &(default_router_list[i].neighbor_entry->next_hop_address))) {
|
---|
| 1789 | return i;
|
---|
| 1790 | }
|
---|
| 1791 | }
|
---|
| 1792 |
|
---|
| 1793 | /* router not found. */
|
---|
| 1794 | return -1;
|
---|
| 1795 | }
|
---|
| 1796 |
|
---|
| 1797 | /**
|
---|
| 1798 | * Create a new entry for a default router.
|
---|
| 1799 | *
|
---|
| 1800 | * @param router_addr the IPv6 address of the router
|
---|
| 1801 | * @param netif the netif on which the router is connected, if known
|
---|
| 1802 | * @return the index on the router table, or -1 if could not be created
|
---|
| 1803 | */
|
---|
| 1804 | static s8_t
|
---|
| 1805 | nd6_new_router(const ip6_addr_t *router_addr, struct netif *netif)
|
---|
| 1806 | {
|
---|
| 1807 | s8_t router_index;
|
---|
| 1808 | s8_t free_router_index;
|
---|
| 1809 | s8_t neighbor_index;
|
---|
| 1810 |
|
---|
| 1811 | IP6_ADDR_ZONECHECK_NETIF(router_addr, netif);
|
---|
| 1812 |
|
---|
| 1813 | /* Do we have a neighbor entry for this router? */
|
---|
| 1814 | neighbor_index = nd6_find_neighbor_cache_entry(router_addr);
|
---|
| 1815 | if (neighbor_index < 0) {
|
---|
| 1816 | /* Create a neighbor entry for this router. */
|
---|
| 1817 | neighbor_index = nd6_new_neighbor_cache_entry();
|
---|
| 1818 | if (neighbor_index < 0) {
|
---|
| 1819 | /* Could not create neighbor entry for this router. */
|
---|
| 1820 | return -1;
|
---|
| 1821 | }
|
---|
| 1822 | ip6_addr_set(&(neighbor_cache[neighbor_index].next_hop_address), router_addr);
|
---|
| 1823 | neighbor_cache[neighbor_index].netif = netif;
|
---|
| 1824 | neighbor_cache[neighbor_index].q = NULL;
|
---|
| 1825 | neighbor_cache[neighbor_index].state = ND6_INCOMPLETE;
|
---|
| 1826 | neighbor_cache[neighbor_index].counter.probes_sent = 1;
|
---|
| 1827 | nd6_send_neighbor_cache_probe(&neighbor_cache[neighbor_index], ND6_SEND_FLAG_MULTICAST_DEST);
|
---|
| 1828 | }
|
---|
| 1829 |
|
---|
| 1830 | /* Mark neighbor as router. */
|
---|
| 1831 | neighbor_cache[neighbor_index].isrouter = 1;
|
---|
| 1832 |
|
---|
| 1833 | /* Look for empty entry. */
|
---|
| 1834 | free_router_index = LWIP_ND6_NUM_ROUTERS;
|
---|
| 1835 | for (router_index = LWIP_ND6_NUM_ROUTERS - 1; router_index >= 0; router_index--) {
|
---|
| 1836 | /* check if router already exists (this is a special case for 2 netifs on the same subnet
|
---|
| 1837 | - e.g. wifi and cable) */
|
---|
| 1838 | if(default_router_list[router_index].neighbor_entry == &(neighbor_cache[neighbor_index])){
|
---|
| 1839 | return router_index;
|
---|
| 1840 | }
|
---|
| 1841 | if (default_router_list[router_index].neighbor_entry == NULL) {
|
---|
| 1842 | /* remember lowest free index to create a new entry */
|
---|
| 1843 | free_router_index = router_index;
|
---|
| 1844 | }
|
---|
| 1845 | }
|
---|
| 1846 | if (free_router_index < LWIP_ND6_NUM_ROUTERS) {
|
---|
| 1847 | default_router_list[free_router_index].neighbor_entry = &(neighbor_cache[neighbor_index]);
|
---|
| 1848 | return free_router_index;
|
---|
| 1849 | }
|
---|
| 1850 |
|
---|
| 1851 | /* Could not create a router entry. */
|
---|
| 1852 |
|
---|
| 1853 | /* Mark neighbor entry as not-router. Entry might be useful as neighbor still. */
|
---|
| 1854 | neighbor_cache[neighbor_index].isrouter = 0;
|
---|
| 1855 |
|
---|
| 1856 | /* router not found. */
|
---|
| 1857 | return -1;
|
---|
| 1858 | }
|
---|
| 1859 |
|
---|
| 1860 | /**
|
---|
| 1861 | * Find the cached entry for an on-link prefix.
|
---|
| 1862 | *
|
---|
| 1863 | * @param prefix the IPv6 prefix that is on-link
|
---|
| 1864 | * @param netif the netif on which the prefix is on-link
|
---|
| 1865 | * @return the index on the prefix table, or -1 if not found
|
---|
| 1866 | */
|
---|
| 1867 | static s8_t
|
---|
| 1868 | nd6_get_onlink_prefix(const ip6_addr_t *prefix, struct netif *netif)
|
---|
| 1869 | {
|
---|
| 1870 | s8_t i;
|
---|
| 1871 |
|
---|
| 1872 | /* Look for prefix in list. */
|
---|
| 1873 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; ++i) {
|
---|
| 1874 | if ((ip6_addr_netcmp(&(prefix_list[i].prefix), prefix)) &&
|
---|
| 1875 | (prefix_list[i].netif == netif)) {
|
---|
| 1876 | return i;
|
---|
| 1877 | }
|
---|
| 1878 | }
|
---|
| 1879 |
|
---|
| 1880 | /* Entry not available. */
|
---|
| 1881 | return -1;
|
---|
| 1882 | }
|
---|
| 1883 |
|
---|
| 1884 | /**
|
---|
| 1885 | * Creates a new entry for an on-link prefix.
|
---|
| 1886 | *
|
---|
| 1887 | * @param prefix the IPv6 prefix that is on-link
|
---|
| 1888 | * @param netif the netif on which the prefix is on-link
|
---|
| 1889 | * @return the index on the prefix table, or -1 if not created
|
---|
| 1890 | */
|
---|
| 1891 | static s8_t
|
---|
| 1892 | nd6_new_onlink_prefix(const ip6_addr_t *prefix, struct netif *netif)
|
---|
| 1893 | {
|
---|
| 1894 | s8_t i;
|
---|
| 1895 |
|
---|
| 1896 | /* Create new entry. */
|
---|
| 1897 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; ++i) {
|
---|
| 1898 | if ((prefix_list[i].netif == NULL) ||
|
---|
| 1899 | (prefix_list[i].invalidation_timer == 0)) {
|
---|
| 1900 | /* Found empty prefix entry. */
|
---|
| 1901 | prefix_list[i].netif = netif;
|
---|
| 1902 | ip6_addr_set(&(prefix_list[i].prefix), prefix);
|
---|
| 1903 | return i;
|
---|
| 1904 | }
|
---|
| 1905 | }
|
---|
| 1906 |
|
---|
| 1907 | /* Entry not available. */
|
---|
| 1908 | return -1;
|
---|
| 1909 | }
|
---|
| 1910 |
|
---|
| 1911 | /**
|
---|
| 1912 | * Determine the next hop for a destination. Will determine if the
|
---|
| 1913 | * destination is on-link, else a suitable on-link router is selected.
|
---|
| 1914 | *
|
---|
| 1915 | * The last entry index is cached for fast entry search.
|
---|
| 1916 | *
|
---|
| 1917 | * @param ip6addr the destination address
|
---|
| 1918 | * @param netif the netif on which the packet will be sent
|
---|
| 1919 | * @return the neighbor cache entry for the next hop, ERR_RTE if no
|
---|
| 1920 | * suitable next hop was found, ERR_MEM if no cache entry
|
---|
| 1921 | * could be created
|
---|
| 1922 | */
|
---|
| 1923 | static s8_t
|
---|
| 1924 | nd6_get_next_hop_entry(const ip6_addr_t *ip6addr, struct netif *netif)
|
---|
| 1925 | {
|
---|
| 1926 | #ifdef LWIP_HOOK_ND6_GET_GW
|
---|
| 1927 | const ip6_addr_t *next_hop_addr;
|
---|
| 1928 | #endif /* LWIP_HOOK_ND6_GET_GW */
|
---|
| 1929 | s8_t i;
|
---|
| 1930 | s16_t dst_idx;
|
---|
| 1931 |
|
---|
| 1932 | IP6_ADDR_ZONECHECK_NETIF(ip6addr, netif);
|
---|
| 1933 |
|
---|
| 1934 | #if LWIP_NETIF_HWADDRHINT
|
---|
| 1935 | if (netif->hints != NULL) {
|
---|
| 1936 | /* per-pcb cached entry was given */
|
---|
| 1937 | netif_addr_idx_t addr_hint = netif->hints->addr_hint;
|
---|
| 1938 | if (addr_hint < LWIP_ND6_NUM_DESTINATIONS) {
|
---|
| 1939 | nd6_cached_destination_index = addr_hint;
|
---|
| 1940 | }
|
---|
| 1941 | }
|
---|
| 1942 | #endif /* LWIP_NETIF_HWADDRHINT */
|
---|
| 1943 |
|
---|
| 1944 | /* Look for ip6addr in destination cache. */
|
---|
| 1945 | if (ip6_addr_cmp(ip6addr, &(destination_cache[nd6_cached_destination_index].destination_addr))) {
|
---|
| 1946 | /* the cached entry index is the right one! */
|
---|
| 1947 | /* do nothing. */
|
---|
| 1948 | ND6_STATS_INC(nd6.cachehit);
|
---|
| 1949 | } else {
|
---|
| 1950 | /* Search destination cache. */
|
---|
| 1951 | dst_idx = nd6_find_destination_cache_entry(ip6addr);
|
---|
| 1952 | if (dst_idx >= 0) {
|
---|
| 1953 | /* found destination entry. make it our new cached index. */
|
---|
| 1954 | LWIP_ASSERT("type overflow", (size_t)dst_idx < NETIF_ADDR_IDX_MAX);
|
---|
| 1955 | nd6_cached_destination_index = (netif_addr_idx_t)dst_idx;
|
---|
| 1956 | } else {
|
---|
| 1957 | /* Not found. Create a new destination entry. */
|
---|
| 1958 | dst_idx = nd6_new_destination_cache_entry();
|
---|
| 1959 | if (dst_idx >= 0) {
|
---|
| 1960 | /* got new destination entry. make it our new cached index. */
|
---|
| 1961 | LWIP_ASSERT("type overflow", (size_t)dst_idx < NETIF_ADDR_IDX_MAX);
|
---|
| 1962 | nd6_cached_destination_index = (netif_addr_idx_t)dst_idx;
|
---|
| 1963 | } else {
|
---|
| 1964 | /* Could not create a destination cache entry. */
|
---|
| 1965 | return ERR_MEM;
|
---|
| 1966 | }
|
---|
| 1967 |
|
---|
| 1968 | /* Copy dest address to destination cache. */
|
---|
| 1969 | ip6_addr_set(&(destination_cache[nd6_cached_destination_index].destination_addr), ip6addr);
|
---|
| 1970 |
|
---|
| 1971 | /* Now find the next hop. is it a neighbor? */
|
---|
| 1972 | if (ip6_addr_islinklocal(ip6addr) ||
|
---|
| 1973 | nd6_is_prefix_in_netif(ip6addr, netif)) {
|
---|
| 1974 | /* Destination in local link. */
|
---|
| 1975 | destination_cache[nd6_cached_destination_index].pmtu = netif_mtu6(netif);
|
---|
| 1976 | ip6_addr_copy(destination_cache[nd6_cached_destination_index].next_hop_addr, destination_cache[nd6_cached_destination_index].destination_addr);
|
---|
| 1977 | #ifdef LWIP_HOOK_ND6_GET_GW
|
---|
| 1978 | } else if ((next_hop_addr = LWIP_HOOK_ND6_GET_GW(netif, ip6addr)) != NULL) {
|
---|
| 1979 | /* Next hop for destination provided by hook function. */
|
---|
| 1980 | destination_cache[nd6_cached_destination_index].pmtu = netif->mtu;
|
---|
| 1981 | ip6_addr_set(&destination_cache[nd6_cached_destination_index].next_hop_addr, next_hop_addr);
|
---|
| 1982 | #endif /* LWIP_HOOK_ND6_GET_GW */
|
---|
| 1983 | } else {
|
---|
| 1984 | /* We need to select a router. */
|
---|
| 1985 | i = nd6_select_router(ip6addr, netif);
|
---|
| 1986 | if (i < 0) {
|
---|
| 1987 | /* No router found. */
|
---|
| 1988 | ip6_addr_set_any(&(destination_cache[nd6_cached_destination_index].destination_addr));
|
---|
| 1989 | return ERR_RTE;
|
---|
| 1990 | }
|
---|
| 1991 | destination_cache[nd6_cached_destination_index].pmtu = netif_mtu6(netif); /* Start with netif mtu, correct through ICMPv6 if necessary */
|
---|
| 1992 | ip6_addr_copy(destination_cache[nd6_cached_destination_index].next_hop_addr, default_router_list[i].neighbor_entry->next_hop_address);
|
---|
| 1993 | }
|
---|
| 1994 | }
|
---|
| 1995 | }
|
---|
| 1996 |
|
---|
| 1997 | #if LWIP_NETIF_HWADDRHINT
|
---|
| 1998 | if (netif->hints != NULL) {
|
---|
| 1999 | /* per-pcb cached entry was given */
|
---|
| 2000 | netif->hints->addr_hint = nd6_cached_destination_index;
|
---|
| 2001 | }
|
---|
| 2002 | #endif /* LWIP_NETIF_HWADDRHINT */
|
---|
| 2003 |
|
---|
| 2004 | /* Look in neighbor cache for the next-hop address. */
|
---|
| 2005 | if (ip6_addr_cmp(&(destination_cache[nd6_cached_destination_index].next_hop_addr),
|
---|
| 2006 | &(neighbor_cache[nd6_cached_neighbor_index].next_hop_address))) {
|
---|
| 2007 | /* Cache hit. */
|
---|
| 2008 | /* Do nothing. */
|
---|
| 2009 | ND6_STATS_INC(nd6.cachehit);
|
---|
| 2010 | } else {
|
---|
| 2011 | i = nd6_find_neighbor_cache_entry(&(destination_cache[nd6_cached_destination_index].next_hop_addr));
|
---|
| 2012 | if (i >= 0) {
|
---|
| 2013 | /* Found a matching record, make it new cached entry. */
|
---|
| 2014 | nd6_cached_neighbor_index = i;
|
---|
| 2015 | } else {
|
---|
| 2016 | /* Neighbor not in cache. Make a new entry. */
|
---|
| 2017 | i = nd6_new_neighbor_cache_entry();
|
---|
| 2018 | if (i >= 0) {
|
---|
| 2019 | /* got new neighbor entry. make it our new cached index. */
|
---|
| 2020 | nd6_cached_neighbor_index = i;
|
---|
| 2021 | } else {
|
---|
| 2022 | /* Could not create a neighbor cache entry. */
|
---|
| 2023 | return ERR_MEM;
|
---|
| 2024 | }
|
---|
| 2025 |
|
---|
| 2026 | /* Initialize fields. */
|
---|
| 2027 | ip6_addr_copy(neighbor_cache[i].next_hop_address,
|
---|
| 2028 | destination_cache[nd6_cached_destination_index].next_hop_addr);
|
---|
| 2029 | neighbor_cache[i].isrouter = 0;
|
---|
| 2030 | neighbor_cache[i].netif = netif;
|
---|
| 2031 | neighbor_cache[i].state = ND6_INCOMPLETE;
|
---|
| 2032 | neighbor_cache[i].counter.probes_sent = 1;
|
---|
| 2033 | nd6_send_neighbor_cache_probe(&neighbor_cache[i], ND6_SEND_FLAG_MULTICAST_DEST);
|
---|
| 2034 | }
|
---|
| 2035 | }
|
---|
| 2036 |
|
---|
| 2037 | /* Reset this destination's age. */
|
---|
| 2038 | destination_cache[nd6_cached_destination_index].age = 0;
|
---|
| 2039 |
|
---|
| 2040 | return nd6_cached_neighbor_index;
|
---|
| 2041 | }
|
---|
| 2042 |
|
---|
| 2043 | /**
|
---|
| 2044 | * Queue a packet for a neighbor.
|
---|
| 2045 | *
|
---|
| 2046 | * @param neighbor_index the index in the neighbor cache table
|
---|
| 2047 | * @param q packet to be queued
|
---|
| 2048 | * @return ERR_OK if succeeded, ERR_MEM if out of memory
|
---|
| 2049 | */
|
---|
| 2050 | static err_t
|
---|
| 2051 | nd6_queue_packet(s8_t neighbor_index, struct pbuf *q)
|
---|
| 2052 | {
|
---|
| 2053 | err_t result = ERR_MEM;
|
---|
| 2054 | struct pbuf *p;
|
---|
| 2055 | int copy_needed = 0;
|
---|
| 2056 | #if LWIP_ND6_QUEUEING
|
---|
| 2057 | struct nd6_q_entry *new_entry, *r;
|
---|
| 2058 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2059 |
|
---|
| 2060 | if ((neighbor_index < 0) || (neighbor_index >= LWIP_ND6_NUM_NEIGHBORS)) {
|
---|
| 2061 | return ERR_ARG;
|
---|
| 2062 | }
|
---|
| 2063 |
|
---|
| 2064 | /* IF q includes a pbuf that must be copied, we have to copy the whole chain
|
---|
| 2065 | * into a new PBUF_RAM. See the definition of PBUF_NEEDS_COPY for details. */
|
---|
| 2066 | p = q;
|
---|
| 2067 | while (p) {
|
---|
| 2068 | if (PBUF_NEEDS_COPY(p)) {
|
---|
| 2069 | copy_needed = 1;
|
---|
| 2070 | break;
|
---|
| 2071 | }
|
---|
| 2072 | p = p->next;
|
---|
| 2073 | }
|
---|
| 2074 | if (copy_needed) {
|
---|
| 2075 | /* copy the whole packet into new pbufs */
|
---|
| 2076 | p = pbuf_clone(PBUF_LINK, PBUF_RAM, q);
|
---|
| 2077 | while ((p == NULL) && (neighbor_cache[neighbor_index].q != NULL)) {
|
---|
| 2078 | /* Free oldest packet (as per RFC recommendation) */
|
---|
| 2079 | #if LWIP_ND6_QUEUEING
|
---|
| 2080 | r = neighbor_cache[neighbor_index].q;
|
---|
| 2081 | neighbor_cache[neighbor_index].q = r->next;
|
---|
| 2082 | r->next = NULL;
|
---|
| 2083 | nd6_free_q(r);
|
---|
| 2084 | #else /* LWIP_ND6_QUEUEING */
|
---|
| 2085 | pbuf_free(neighbor_cache[neighbor_index].q);
|
---|
| 2086 | neighbor_cache[neighbor_index].q = NULL;
|
---|
| 2087 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2088 | p = pbuf_clone(PBUF_LINK, PBUF_RAM, q);
|
---|
| 2089 | }
|
---|
| 2090 | } else {
|
---|
| 2091 | /* referencing the old pbuf is enough */
|
---|
| 2092 | p = q;
|
---|
| 2093 | pbuf_ref(p);
|
---|
| 2094 | }
|
---|
| 2095 | /* packet was copied/ref'd? */
|
---|
| 2096 | if (p != NULL) {
|
---|
| 2097 | /* queue packet ... */
|
---|
| 2098 | #if LWIP_ND6_QUEUEING
|
---|
| 2099 | /* allocate a new nd6 queue entry */
|
---|
| 2100 | new_entry = (struct nd6_q_entry *)memp_malloc(MEMP_ND6_QUEUE);
|
---|
| 2101 | if ((new_entry == NULL) && (neighbor_cache[neighbor_index].q != NULL)) {
|
---|
| 2102 | /* Free oldest packet (as per RFC recommendation) */
|
---|
| 2103 | r = neighbor_cache[neighbor_index].q;
|
---|
| 2104 | neighbor_cache[neighbor_index].q = r->next;
|
---|
| 2105 | r->next = NULL;
|
---|
| 2106 | nd6_free_q(r);
|
---|
| 2107 | new_entry = (struct nd6_q_entry *)memp_malloc(MEMP_ND6_QUEUE);
|
---|
| 2108 | }
|
---|
| 2109 | if (new_entry != NULL) {
|
---|
| 2110 | new_entry->next = NULL;
|
---|
| 2111 | new_entry->p = p;
|
---|
| 2112 | if (neighbor_cache[neighbor_index].q != NULL) {
|
---|
| 2113 | /* queue was already existent, append the new entry to the end */
|
---|
| 2114 | r = neighbor_cache[neighbor_index].q;
|
---|
| 2115 | while (r->next != NULL) {
|
---|
| 2116 | r = r->next;
|
---|
| 2117 | }
|
---|
| 2118 | r->next = new_entry;
|
---|
| 2119 | } else {
|
---|
| 2120 | /* queue did not exist, first item in queue */
|
---|
| 2121 | neighbor_cache[neighbor_index].q = new_entry;
|
---|
| 2122 | }
|
---|
| 2123 | LWIP_DEBUGF(LWIP_DBG_TRACE, ("ipv6: queued packet %p on neighbor entry %"S16_F"\n", (void *)p, (s16_t)neighbor_index));
|
---|
| 2124 | result = ERR_OK;
|
---|
| 2125 | } else {
|
---|
| 2126 | /* the pool MEMP_ND6_QUEUE is empty */
|
---|
| 2127 | pbuf_free(p);
|
---|
| 2128 | LWIP_DEBUGF(LWIP_DBG_TRACE, ("ipv6: could not queue a copy of packet %p (out of memory)\n", (void *)p));
|
---|
| 2129 | /* { result == ERR_MEM } through initialization */
|
---|
| 2130 | }
|
---|
| 2131 | #else /* LWIP_ND6_QUEUEING */
|
---|
| 2132 | /* Queue a single packet. If an older packet is already queued, free it as per RFC. */
|
---|
| 2133 | if (neighbor_cache[neighbor_index].q != NULL) {
|
---|
| 2134 | pbuf_free(neighbor_cache[neighbor_index].q);
|
---|
| 2135 | }
|
---|
| 2136 | neighbor_cache[neighbor_index].q = p;
|
---|
| 2137 | LWIP_DEBUGF(LWIP_DBG_TRACE, ("ipv6: queued packet %p on neighbor entry %"S16_F"\n", (void *)p, (s16_t)neighbor_index));
|
---|
| 2138 | result = ERR_OK;
|
---|
| 2139 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2140 | } else {
|
---|
| 2141 | LWIP_DEBUGF(LWIP_DBG_TRACE, ("ipv6: could not queue a copy of packet %p (out of memory)\n", (void *)q));
|
---|
| 2142 | /* { result == ERR_MEM } through initialization */
|
---|
| 2143 | }
|
---|
| 2144 |
|
---|
| 2145 | return result;
|
---|
| 2146 | }
|
---|
| 2147 |
|
---|
| 2148 | #if LWIP_ND6_QUEUEING
|
---|
| 2149 | /**
|
---|
| 2150 | * Free a complete queue of nd6 q entries
|
---|
| 2151 | *
|
---|
| 2152 | * @param q a queue of nd6_q_entry to free
|
---|
| 2153 | */
|
---|
| 2154 | static void
|
---|
| 2155 | nd6_free_q(struct nd6_q_entry *q)
|
---|
| 2156 | {
|
---|
| 2157 | struct nd6_q_entry *r;
|
---|
| 2158 | LWIP_ASSERT("q != NULL", q != NULL);
|
---|
| 2159 | LWIP_ASSERT("q->p != NULL", q->p != NULL);
|
---|
| 2160 | while (q) {
|
---|
| 2161 | r = q;
|
---|
| 2162 | q = q->next;
|
---|
| 2163 | LWIP_ASSERT("r->p != NULL", (r->p != NULL));
|
---|
| 2164 | pbuf_free(r->p);
|
---|
| 2165 | memp_free(MEMP_ND6_QUEUE, r);
|
---|
| 2166 | }
|
---|
| 2167 | }
|
---|
| 2168 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2169 |
|
---|
| 2170 | /**
|
---|
| 2171 | * Send queued packets for a neighbor
|
---|
| 2172 | *
|
---|
| 2173 | * @param i the neighbor to send packets to
|
---|
| 2174 | */
|
---|
| 2175 | static void
|
---|
| 2176 | nd6_send_q(s8_t i)
|
---|
| 2177 | {
|
---|
| 2178 | struct ip6_hdr *ip6hdr;
|
---|
| 2179 | ip6_addr_t dest;
|
---|
| 2180 | #if LWIP_ND6_QUEUEING
|
---|
| 2181 | struct nd6_q_entry *q;
|
---|
| 2182 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2183 |
|
---|
| 2184 | if ((i < 0) || (i >= LWIP_ND6_NUM_NEIGHBORS)) {
|
---|
| 2185 | return;
|
---|
| 2186 | }
|
---|
| 2187 |
|
---|
| 2188 | #if LWIP_ND6_QUEUEING
|
---|
| 2189 | while (neighbor_cache[i].q != NULL) {
|
---|
| 2190 | /* remember first in queue */
|
---|
| 2191 | q = neighbor_cache[i].q;
|
---|
| 2192 | /* pop first item off the queue */
|
---|
| 2193 | neighbor_cache[i].q = q->next;
|
---|
| 2194 | /* Get ipv6 header. */
|
---|
| 2195 | ip6hdr = (struct ip6_hdr *)(q->p->payload);
|
---|
| 2196 | /* Create an aligned copy. */
|
---|
| 2197 | ip6_addr_copy_from_packed(dest, ip6hdr->dest);
|
---|
| 2198 | /* Restore the zone, if applicable. */
|
---|
| 2199 | ip6_addr_assign_zone(&dest, IP6_UNKNOWN, neighbor_cache[i].netif);
|
---|
| 2200 | /* send the queued IPv6 packet */
|
---|
| 2201 | (neighbor_cache[i].netif)->output_ip6(neighbor_cache[i].netif, q->p, &dest);
|
---|
| 2202 | /* free the queued IP packet */
|
---|
| 2203 | pbuf_free(q->p);
|
---|
| 2204 | /* now queue entry can be freed */
|
---|
| 2205 | memp_free(MEMP_ND6_QUEUE, q);
|
---|
| 2206 | }
|
---|
| 2207 | #else /* LWIP_ND6_QUEUEING */
|
---|
| 2208 | if (neighbor_cache[i].q != NULL) {
|
---|
| 2209 | /* Get ipv6 header. */
|
---|
| 2210 | ip6hdr = (struct ip6_hdr *)(neighbor_cache[i].q->payload);
|
---|
| 2211 | /* Create an aligned copy. */
|
---|
| 2212 | ip6_addr_copy_from_packed(dest, ip6hdr->dest);
|
---|
| 2213 | /* Restore the zone, if applicable. */
|
---|
| 2214 | ip6_addr_assign_zone(&dest, IP6_UNKNOWN, neighbor_cache[i].netif);
|
---|
| 2215 | /* send the queued IPv6 packet */
|
---|
| 2216 | (neighbor_cache[i].netif)->output_ip6(neighbor_cache[i].netif, neighbor_cache[i].q, &dest);
|
---|
| 2217 | /* free the queued IP packet */
|
---|
| 2218 | pbuf_free(neighbor_cache[i].q);
|
---|
| 2219 | neighbor_cache[i].q = NULL;
|
---|
| 2220 | }
|
---|
| 2221 | #endif /* LWIP_ND6_QUEUEING */
|
---|
| 2222 | }
|
---|
| 2223 |
|
---|
| 2224 | /**
|
---|
| 2225 | * A packet is to be transmitted to a specific IPv6 destination on a specific
|
---|
| 2226 | * interface. Check if we can find the hardware address of the next hop to use
|
---|
| 2227 | * for the packet. If so, give the hardware address to the caller, which should
|
---|
| 2228 | * use it to send the packet right away. Otherwise, enqueue the packet for
|
---|
| 2229 | * later transmission while looking up the hardware address, if possible.
|
---|
| 2230 | *
|
---|
| 2231 | * As such, this function returns one of three different possible results:
|
---|
| 2232 | *
|
---|
| 2233 | * - ERR_OK with a non-NULL 'hwaddrp': the caller should send the packet now.
|
---|
| 2234 | * - ERR_OK with a NULL 'hwaddrp': the packet has been enqueued for later.
|
---|
| 2235 | * - not ERR_OK: something went wrong; forward the error upward in the stack.
|
---|
| 2236 | *
|
---|
| 2237 | * @param netif The lwIP network interface on which the IP packet will be sent.
|
---|
| 2238 | * @param q The pbuf(s) containing the IP packet to be sent.
|
---|
| 2239 | * @param ip6addr The destination IPv6 address of the packet.
|
---|
| 2240 | * @param hwaddrp On success, filled with a pointer to a HW address or NULL (meaning
|
---|
| 2241 | * the packet has been queued).
|
---|
| 2242 | * @return
|
---|
| 2243 | * - ERR_OK on success, ERR_RTE if no route was found for the packet,
|
---|
| 2244 | * or ERR_MEM if low memory conditions prohibit sending the packet at all.
|
---|
| 2245 | */
|
---|
| 2246 | err_t
|
---|
| 2247 | nd6_get_next_hop_addr_or_queue(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr, const u8_t **hwaddrp)
|
---|
| 2248 | {
|
---|
| 2249 | s8_t i;
|
---|
| 2250 |
|
---|
| 2251 | /* Get next hop record. */
|
---|
| 2252 | i = nd6_get_next_hop_entry(ip6addr, netif);
|
---|
| 2253 | if (i < 0) {
|
---|
| 2254 | /* failed to get a next hop neighbor record. */
|
---|
| 2255 | return i;
|
---|
| 2256 | }
|
---|
| 2257 |
|
---|
| 2258 | /* Now that we have a destination record, send or queue the packet. */
|
---|
| 2259 | if (neighbor_cache[i].state == ND6_STALE) {
|
---|
| 2260 | /* Switch to delay state. */
|
---|
| 2261 | neighbor_cache[i].state = ND6_DELAY;
|
---|
| 2262 | neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
|
---|
| 2263 | }
|
---|
| 2264 | /* @todo should we send or queue if PROBE? send for now, to let unicast NS pass. */
|
---|
| 2265 | if ((neighbor_cache[i].state == ND6_REACHABLE) ||
|
---|
| 2266 | (neighbor_cache[i].state == ND6_DELAY) ||
|
---|
| 2267 | (neighbor_cache[i].state == ND6_PROBE)) {
|
---|
| 2268 |
|
---|
| 2269 | /* Tell the caller to send out the packet now. */
|
---|
| 2270 | *hwaddrp = neighbor_cache[i].lladdr;
|
---|
| 2271 | return ERR_OK;
|
---|
| 2272 | }
|
---|
| 2273 |
|
---|
| 2274 | /* We should queue packet on this interface. */
|
---|
| 2275 | *hwaddrp = NULL;
|
---|
| 2276 | return nd6_queue_packet(i, q);
|
---|
| 2277 | }
|
---|
| 2278 |
|
---|
| 2279 |
|
---|
| 2280 | /**
|
---|
| 2281 | * Get the Path MTU for a destination.
|
---|
| 2282 | *
|
---|
| 2283 | * @param ip6addr the destination address
|
---|
| 2284 | * @param netif the netif on which the packet will be sent
|
---|
| 2285 | * @return the Path MTU, if known, or the netif default MTU
|
---|
| 2286 | */
|
---|
| 2287 | u16_t
|
---|
| 2288 | nd6_get_destination_mtu(const ip6_addr_t *ip6addr, struct netif *netif)
|
---|
| 2289 | {
|
---|
| 2290 | s16_t i;
|
---|
| 2291 |
|
---|
| 2292 | i = nd6_find_destination_cache_entry(ip6addr);
|
---|
| 2293 | if (i >= 0) {
|
---|
| 2294 | if (destination_cache[i].pmtu > 0) {
|
---|
| 2295 | return destination_cache[i].pmtu;
|
---|
| 2296 | }
|
---|
| 2297 | }
|
---|
| 2298 |
|
---|
| 2299 | if (netif != NULL) {
|
---|
| 2300 | return netif_mtu6(netif);
|
---|
| 2301 | }
|
---|
| 2302 |
|
---|
| 2303 | return 1280; /* Minimum MTU */
|
---|
| 2304 | }
|
---|
| 2305 |
|
---|
| 2306 |
|
---|
| 2307 | #if LWIP_ND6_TCP_REACHABILITY_HINTS
|
---|
| 2308 | /**
|
---|
| 2309 | * Provide the Neighbor discovery process with a hint that a
|
---|
| 2310 | * destination is reachable. Called by tcp_receive when ACKs are
|
---|
| 2311 | * received or sent (as per RFC). This is useful to avoid sending
|
---|
| 2312 | * NS messages every 30 seconds.
|
---|
| 2313 | *
|
---|
| 2314 | * @param ip6addr the destination address which is know to be reachable
|
---|
| 2315 | * by an upper layer protocol (TCP)
|
---|
| 2316 | */
|
---|
| 2317 | void
|
---|
| 2318 | nd6_reachability_hint(const ip6_addr_t *ip6addr)
|
---|
| 2319 | {
|
---|
| 2320 | s8_t i;
|
---|
| 2321 | s16_t dst_idx;
|
---|
| 2322 |
|
---|
| 2323 | /* Find destination in cache. */
|
---|
| 2324 | if (ip6_addr_cmp(ip6addr, &(destination_cache[nd6_cached_destination_index].destination_addr))) {
|
---|
| 2325 | dst_idx = nd6_cached_destination_index;
|
---|
| 2326 | ND6_STATS_INC(nd6.cachehit);
|
---|
| 2327 | } else {
|
---|
| 2328 | dst_idx = nd6_find_destination_cache_entry(ip6addr);
|
---|
| 2329 | }
|
---|
| 2330 | if (dst_idx < 0) {
|
---|
| 2331 | return;
|
---|
| 2332 | }
|
---|
| 2333 |
|
---|
| 2334 | /* Find next hop neighbor in cache. */
|
---|
| 2335 | if (ip6_addr_cmp(&(destination_cache[dst_idx].next_hop_addr), &(neighbor_cache[nd6_cached_neighbor_index].next_hop_address))) {
|
---|
| 2336 | i = nd6_cached_neighbor_index;
|
---|
| 2337 | ND6_STATS_INC(nd6.cachehit);
|
---|
| 2338 | } else {
|
---|
| 2339 | i = nd6_find_neighbor_cache_entry(&(destination_cache[dst_idx].next_hop_addr));
|
---|
| 2340 | }
|
---|
| 2341 | if (i < 0) {
|
---|
| 2342 | return;
|
---|
| 2343 | }
|
---|
| 2344 |
|
---|
| 2345 | /* For safety: don't set as reachable if we don't have a LL address yet. Misuse protection. */
|
---|
| 2346 | if (neighbor_cache[i].state == ND6_INCOMPLETE || neighbor_cache[i].state == ND6_NO_ENTRY) {
|
---|
| 2347 | return;
|
---|
| 2348 | }
|
---|
| 2349 |
|
---|
| 2350 | /* Set reachability state. */
|
---|
| 2351 | neighbor_cache[i].state = ND6_REACHABLE;
|
---|
| 2352 | neighbor_cache[i].counter.reachable_time = reachable_time;
|
---|
| 2353 | }
|
---|
| 2354 | #endif /* LWIP_ND6_TCP_REACHABILITY_HINTS */
|
---|
| 2355 |
|
---|
| 2356 | /**
|
---|
| 2357 | * Remove all prefix, neighbor_cache and router entries of the specified netif.
|
---|
| 2358 | *
|
---|
| 2359 | * @param netif points to a network interface
|
---|
| 2360 | */
|
---|
| 2361 | void
|
---|
| 2362 | nd6_cleanup_netif(struct netif *netif)
|
---|
| 2363 | {
|
---|
| 2364 | u8_t i;
|
---|
| 2365 | s8_t router_index;
|
---|
| 2366 | for (i = 0; i < LWIP_ND6_NUM_PREFIXES; i++) {
|
---|
| 2367 | if (prefix_list[i].netif == netif) {
|
---|
| 2368 | prefix_list[i].netif = NULL;
|
---|
| 2369 | }
|
---|
| 2370 | }
|
---|
| 2371 | for (i = 0; i < LWIP_ND6_NUM_NEIGHBORS; i++) {
|
---|
| 2372 | if (neighbor_cache[i].netif == netif) {
|
---|
| 2373 | for (router_index = 0; router_index < LWIP_ND6_NUM_ROUTERS; router_index++) {
|
---|
| 2374 | if (default_router_list[router_index].neighbor_entry == &neighbor_cache[i]) {
|
---|
| 2375 | default_router_list[router_index].neighbor_entry = NULL;
|
---|
| 2376 | default_router_list[router_index].flags = 0;
|
---|
| 2377 | }
|
---|
| 2378 | }
|
---|
| 2379 | neighbor_cache[i].isrouter = 0;
|
---|
| 2380 | nd6_free_neighbor_cache_entry(i);
|
---|
| 2381 | }
|
---|
| 2382 | }
|
---|
| 2383 | /* Clear the destination cache, since many entries may now have become
|
---|
| 2384 | * invalid for one of several reasons. As destination cache entries have no
|
---|
| 2385 | * netif association, use a sledgehammer approach (this can be improved). */
|
---|
| 2386 | nd6_clear_destination_cache();
|
---|
| 2387 | }
|
---|
| 2388 |
|
---|
| 2389 | #if LWIP_IPV6_MLD
|
---|
| 2390 | /**
|
---|
| 2391 | * The state of a local IPv6 address entry is about to change. If needed, join
|
---|
| 2392 | * or leave the solicited-node multicast group for the address.
|
---|
| 2393 | *
|
---|
| 2394 | * @param netif The netif that owns the address.
|
---|
| 2395 | * @param addr_idx The index of the address.
|
---|
| 2396 | * @param new_state The new (IP6_ADDR_) state for the address.
|
---|
| 2397 | */
|
---|
| 2398 | void
|
---|
| 2399 | nd6_adjust_mld_membership(struct netif *netif, s8_t addr_idx, u8_t new_state)
|
---|
| 2400 | {
|
---|
| 2401 | u8_t old_state, old_member, new_member;
|
---|
| 2402 |
|
---|
| 2403 | old_state = netif_ip6_addr_state(netif, addr_idx);
|
---|
| 2404 |
|
---|
| 2405 | /* Determine whether we were, and should be, a member of the solicited-node
|
---|
| 2406 | * multicast group for this address. For tentative addresses, the group is
|
---|
| 2407 | * not joined until the address enters the TENTATIVE_1 (or VALID) state. */
|
---|
| 2408 | old_member = (old_state != IP6_ADDR_INVALID && old_state != IP6_ADDR_DUPLICATED && old_state != IP6_ADDR_TENTATIVE);
|
---|
| 2409 | new_member = (new_state != IP6_ADDR_INVALID && new_state != IP6_ADDR_DUPLICATED && new_state != IP6_ADDR_TENTATIVE);
|
---|
| 2410 |
|
---|
| 2411 | if (old_member != new_member) {
|
---|
| 2412 | ip6_addr_set_solicitednode(&multicast_address, netif_ip6_addr(netif, addr_idx)->addr[3]);
|
---|
| 2413 | ip6_addr_assign_zone(&multicast_address, IP6_MULTICAST, netif);
|
---|
| 2414 |
|
---|
| 2415 | if (new_member) {
|
---|
| 2416 | mld6_joingroup_netif(netif, &multicast_address);
|
---|
| 2417 | } else {
|
---|
| 2418 | mld6_leavegroup_netif(netif, &multicast_address);
|
---|
| 2419 | }
|
---|
| 2420 | }
|
---|
| 2421 | }
|
---|
| 2422 | #endif /* LWIP_IPV6_MLD */
|
---|
| 2423 |
|
---|
| 2424 | /** Netif was added, set up, or reconnected (link up) */
|
---|
| 2425 | void
|
---|
| 2426 | nd6_restart_netif(struct netif *netif)
|
---|
| 2427 | {
|
---|
| 2428 | #if LWIP_IPV6_SEND_ROUTER_SOLICIT
|
---|
| 2429 | /* Send Router Solicitation messages (see RFC 4861, ch. 6.3.7). */
|
---|
| 2430 | netif->rs_count = LWIP_ND6_MAX_MULTICAST_SOLICIT;
|
---|
| 2431 | #endif /* LWIP_IPV6_SEND_ROUTER_SOLICIT */
|
---|
| 2432 | }
|
---|
| 2433 |
|
---|
| 2434 | #endif /* LWIP_IPV6 */
|
---|