Files
my-os-project2/kernel/picotcp/modules/pico_ipv6_nd.c
2025-10-29 14:29:06 +01:00

1587 lines
50 KiB
C

/*********************************************************************
PicoTCP. Copyright (c) 2012-2017 Altran Intelligent Systems. Some rights reserved.
See COPYING, LICENSE.GPLv2 and LICENSE.GPLv3 for usage.
.
Authors: Daniele Lacamera
*********************************************************************/
#include "pico_config.h"
#include "pico_tree.h"
#include "pico_icmp6.h"
#include "pico_ipv6.h"
#include "pico_stack.h"
#include "pico_device.h"
#include "pico_eth.h"
#include "pico_addressing.h"
#include "pico_ipv6_nd.h"
#include "pico_ethernet.h"
#include "pico_6lowpan.h"
#include "pico_6lowpan_ll.h"
#ifdef PICO_SUPPORT_IPV6
#ifdef DEBUG_IPV6_ND
#define nd_dbg dbg
#else
#define nd_dbg(...) do {} while(0)
#endif
#define ONE_MINUTE ((pico_time)(1000 * 60))
#ifdef PICO_SUPPORT_6LOWPAN
#define MAX_RTR_SOLICITATIONS (3)
#define RTR_SOLICITATION_INTERVAL (10000)
#define MAX_RTR_SOLICITATION_INTERVAL (60000)
#endif
static struct pico_frame *frames_queued_v6[PICO_ND_MAX_FRAMES_QUEUED] = {
0
};
enum pico_ipv6_neighbor_state {
PICO_ND_STATE_INCOMPLETE = 0,
PICO_ND_STATE_REACHABLE,
PICO_ND_STATE_STALE,
PICO_ND_STATE_DELAY,
PICO_ND_STATE_PROBE
};
struct pico_ipv6_neighbor {
enum pico_ipv6_neighbor_state state;
struct pico_ip6 address;
union pico_hw_addr hwaddr;
struct pico_device *dev;
uint16_t is_router;
uint16_t failure_count;
pico_time expire;
};
/******************************************************************************
* Function prototypes
******************************************************************************/
#ifdef PICO_SUPPORT_6LOWPAN
static void pico_6lp_nd_deregister(struct pico_ipv6_link *);
static void pico_6lp_nd_unreachable_gateway(struct pico_ip6 *a);
static int pico_6lp_nd_neigh_adv_process(struct pico_frame *f);
static int neigh_sol_detect_dad_6lp(struct pico_frame *f);
#endif
static int pico_ipv6_neighbor_compare(void *ka, void *kb)
{
struct pico_ipv6_neighbor *a = ka, *b = kb;
return pico_ipv6_compare(&a->address, &b->address);
}
PICO_TREE_DECLARE(NCache, pico_ipv6_neighbor_compare);
static struct pico_ipv6_neighbor *pico_nd_find_neighbor(struct pico_ip6 *dst)
{
struct pico_ipv6_neighbor test = {
0
};
test.address = *dst;
return pico_tree_findKey(&NCache, &test);
}
static void pico_ipv6_nd_queued_trigger(void)
{
int i;
struct pico_frame *f;
for (i = 0; i < PICO_ND_MAX_FRAMES_QUEUED; i++)
{
f = frames_queued_v6[i];
if (f) {
if (pico_datalink_send(f) <= 0)
pico_frame_discard(f);
frames_queued_v6[i] = NULL;
}
}
}
static void ipv6_duplicate_detected(struct pico_ipv6_link *l)
{
struct pico_device *dev;
int is_ll = pico_ipv6_is_linklocal(l->address.addr);
dev = l->dev;
dbg("IPV6: Duplicate address detected. Removing link.\n");
pico_ipv6_link_del(l->dev, l->address);
#ifdef PICO_SUPPORT_6LOWPAN
if (PICO_DEV_IS_6LOWPAN(l->dev)) {
pico_6lp_nd_deregister(l);
}
#endif
if (is_ll)
pico_device_ipv6_random_ll(dev);
}
static struct pico_ipv6_neighbor *pico_nd_add(struct pico_ip6 *addr, struct pico_device *dev)
{
struct pico_ipv6_neighbor *n;
char address[120];
/* Create a new NCE */
n = PICO_ZALLOC(sizeof(struct pico_ipv6_neighbor));
if (!n)
return NULL;
pico_ipv6_to_string(address, addr->addr);
memcpy(&n->address, addr, sizeof(struct pico_ip6));
n->dev = dev;
if (pico_tree_insert(&NCache, n)) {
nd_dbg("IPv6 ND: Failed to insert neigbor in tree\n");
PICO_FREE(n);
return NULL;
}
return n;
}
static void pico_ipv6_nd_unreachable(struct pico_ip6 *a)
{
int i;
struct pico_frame *f;
struct pico_ipv6_hdr *hdr;
struct pico_ip6 dst;
#ifdef PICO_SUPPORT_6LOWPAN
/* 6LP: Find any 6LoWPAN-hosts for which this address might have been a default gateway.
* If such a host found, send a router solicitation again */
pico_6lp_nd_unreachable_gateway(a);
#endif /* PICO_SUPPORT_6LOWPAN */
for (i = 0; i < PICO_ND_MAX_FRAMES_QUEUED; i++)
{
f = frames_queued_v6[i];
if (f) {
hdr = (struct pico_ipv6_hdr *) f->net_hdr;
dst = pico_ipv6_route_get_gateway(&hdr->dst);
if (pico_ipv6_is_unspecified(dst.addr))
dst = hdr->dst;
if (memcmp(dst.addr, a->addr, PICO_SIZE_IP6) == 0) {
if (!pico_source_is_local(f)) {
pico_notify_dest_unreachable(f);
}
pico_frame_discard(f);
frames_queued_v6[i] = NULL;
}
}
}
}
static void pico_nd_new_expire_time(struct pico_ipv6_neighbor *n)
{
if (n->state == PICO_ND_STATE_REACHABLE)
n->expire = PICO_TIME_MS() + PICO_ND_REACHABLE_TIME;
else if ((n->state == PICO_ND_STATE_DELAY) || (n->state == PICO_ND_STATE_STALE))
n->expire = PICO_TIME_MS() + PICO_ND_DELAY_FIRST_PROBE_TIME;
else {
n->expire = n->dev->hostvars.retranstime + PICO_TIME_MS();
}
}
static void pico_nd_discover(struct pico_ipv6_neighbor *n)
{
char IPADDR[64];
if (!n) {
return;
} else {
if (n->expire != (pico_time)0) {
return;
} else {
pico_ipv6_to_string(IPADDR, n->address.addr);
/* dbg("Sending NS for %s\n", IPADDR); */
if (++n->failure_count > PICO_ND_MAX_SOLICIT)
return;
if (n->state == PICO_ND_STATE_INCOMPLETE) {
pico_icmp6_neighbor_solicitation(n->dev, &n->address, PICO_ICMP6_ND_SOLICITED, &n->address);
} else {
pico_icmp6_neighbor_solicitation(n->dev, &n->address, PICO_ICMP6_ND_UNICAST, &n->address);
}
pico_nd_new_expire_time(n);
}
}
}
static struct pico_eth *pico_nd_get_neighbor(struct pico_ip6 *addr, struct pico_ipv6_neighbor *n, struct pico_device *dev)
{
/* dbg("Finding neighbor %02x:...:%02x, state = %d\n", addr->addr[0], addr->addr[15], n?n->state:-1); */
if (!n) {
n = pico_nd_add(addr, dev);
pico_nd_discover(n);
return NULL;
} else {
if (n->state == PICO_ND_STATE_INCOMPLETE) {
return NULL;
} else if (n->state == PICO_ND_STATE_STALE) {
n->state = PICO_ND_STATE_DELAY;
pico_nd_new_expire_time(n);
}
if (n->state != PICO_ND_STATE_REACHABLE) {
pico_nd_discover(n);
}
}
return &n->hwaddr.mac;
}
static struct pico_eth *pico_nd_get(struct pico_ip6 *address, struct pico_device *dev)
{
struct pico_ip6 gateway = {{0}}, addr = {{0}};
/* should we use gateway, or is dst local (gateway == 0)? */
gateway = pico_ipv6_route_get_gateway(address);
if (memcmp(gateway.addr, PICO_IP6_ANY, PICO_SIZE_IP6) == 0)
addr = *address;
else
addr = gateway;
return pico_nd_get_neighbor(&addr, pico_nd_find_neighbor(&addr), dev);
}
static int nd_options(uint8_t *options, struct pico_icmp6_opt_lladdr *opt, uint8_t expected_opt, int optlen, int len)
{
uint8_t type = 0;
int found = 0;
while (optlen > 0) {
type = ((struct pico_icmp6_opt_lladdr *)options)->type;
len = ((struct pico_icmp6_opt_lladdr *)options)->len;
optlen -= len << 3; /* len in units of 8 octets */
if (len <= 0)
return -1; /* malformed option. */
if (type == expected_opt) {
if (found > 0)
return -1; /* malformed option: option is there twice. */
memcpy(opt, (struct pico_icmp6_opt_lladdr *)options, sizeof(struct pico_icmp6_opt_lladdr));
found++;
}
if (optlen > 0) {
options += len << 3;
} else { /* parsing options: terminated. */
return found;
}
}
return found;
}
static int neigh_options(struct pico_frame *f, struct pico_icmp6_opt_lladdr *opt, uint8_t expected_opt)
{
/* RFC 4861 $7.1.2 + $7.2.5.
* * The contents of any defined options that are not specified to be used
* * with Neighbor Advertisement messages MUST be ignored and the packet
* * processed as normal. The only defined option that may appear is the
* * Target Link-Layer Address option.
* */
struct pico_icmp6_hdr *icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
uint8_t *option = NULL;
int optlen = 0;
int len = 0;
optlen = f->transport_len - PICO_ICMP6HDR_NEIGH_ADV_SIZE;
if (optlen)
option = ((uint8_t *)&icmp6_hdr->msg.info.neigh_adv) + sizeof(struct neigh_adv_s);
return nd_options(option, opt, expected_opt, optlen, len);
}
static size_t pico_hw_addr_len(struct pico_device *dev, struct pico_icmp6_opt_lladdr *opt)
{
size_t len = PICO_SIZE_ETH;
#ifndef PICO_SUPPORT_6LOWPAN
IGNORE_PARAMETER(dev);
IGNORE_PARAMETER(opt);
#else
if (PICO_DEV_IS_6LOWPAN(dev)) {
if (1 == opt->len) {
len = (size_t)SIZE_6LOWPAN_SHORT;
} else {
len = (size_t)SIZE_6LOWPAN_EXT;
}
}
#endif
return len;
}
static void pico_ipv6_neighbor_update(struct pico_ipv6_neighbor *n, struct pico_icmp6_opt_lladdr *opt, struct pico_device *dev)
{
memcpy(n->hwaddr.data, opt->addr.data, pico_hw_addr_len(dev, opt));
}
static int pico_ipv6_neighbor_compare_stored(struct pico_ipv6_neighbor *n, struct pico_icmp6_opt_lladdr *opt, struct pico_device *dev)
{
return memcmp(n->hwaddr.data, opt->addr.data, pico_hw_addr_len(dev, opt));
}
static void neigh_adv_reconfirm_router_option(struct pico_ipv6_neighbor *n, unsigned int isRouter)
{
if (!isRouter && n->is_router) {
pico_ipv6_router_down(&n->address);
}
if (isRouter)
n->is_router = 1;
else
n->is_router = 0;
}
static int neigh_adv_reconfirm_no_tlla(struct pico_ipv6_neighbor *n, struct pico_icmp6_hdr *hdr)
{
if (IS_SOLICITED(hdr)) {
n->state = PICO_ND_STATE_REACHABLE;
n->failure_count = 0;
pico_ipv6_nd_queued_trigger();
pico_nd_new_expire_time(n);
return 0;
}
return -1;
}
static int neigh_adv_reconfirm(struct pico_ipv6_neighbor *n, struct pico_icmp6_opt_lladdr *opt, struct pico_icmp6_hdr *hdr, struct pico_device *dev)
{
if (IS_SOLICITED(hdr) && !IS_OVERRIDE(hdr) && (pico_ipv6_neighbor_compare_stored(n, opt, dev) == 0)) {
n->state = PICO_ND_STATE_REACHABLE;
n->failure_count = 0;
pico_ipv6_nd_queued_trigger();
pico_nd_new_expire_time(n);
return 0;
}
if ((n->state == PICO_ND_STATE_REACHABLE) && IS_SOLICITED(hdr) && !IS_OVERRIDE(hdr)) {
n->state = PICO_ND_STATE_STALE;
return 0;
}
if (IS_SOLICITED(hdr) && IS_OVERRIDE(hdr)) {
pico_ipv6_neighbor_update(n, opt, dev);
n->state = PICO_ND_STATE_REACHABLE;
n->failure_count = 0;
pico_ipv6_nd_queued_trigger();
pico_nd_new_expire_time(n);
return 0;
}
if (!IS_SOLICITED(hdr) && IS_OVERRIDE(hdr) && (pico_ipv6_neighbor_compare_stored(n, opt, dev) != 0)) {
pico_ipv6_neighbor_update(n, opt, dev);
n->state = PICO_ND_STATE_STALE;
pico_ipv6_nd_queued_trigger();
pico_nd_new_expire_time(n);
return 0;
}
if ((n->state == PICO_ND_STATE_REACHABLE) && (!IS_SOLICITED(hdr)) && (!IS_OVERRIDE(hdr)) &&
(pico_ipv6_neighbor_compare_stored(n, opt, dev) != 0)) {
/* I. If the Override flag is clear and the supplied link-layer address
* differs from that in the cache, then one of two actions takes
* place:
* a. If the state of the entry is REACHABLE, set it to STALE, but
* do not update the entry in any other way.
* b. Otherwise, the received advertisement should be ignored and
* MUST NOT update the cache.
*/
n->state = PICO_ND_STATE_STALE;
pico_nd_new_expire_time(n);
return 0;
}
return -1;
}
static void neigh_adv_process_incomplete(struct pico_ipv6_neighbor *n, struct pico_frame *f, struct pico_icmp6_opt_lladdr *opt)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
if (!n || !f) {
return;
} else {
if (!(icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr))
return;
else {
if (IS_SOLICITED(icmp6_hdr)) {
n->state = PICO_ND_STATE_REACHABLE;
n->failure_count = 0;
pico_nd_new_expire_time(n);
} else {
n->state = PICO_ND_STATE_STALE;
}
if (opt)
pico_ipv6_neighbor_update(n, opt, f->dev);
pico_ipv6_nd_queued_trigger();
}
}
}
static int neigh_adv_process(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
struct pico_ipv6_neighbor *n = NULL;
struct pico_icmp6_opt_lladdr opt = {
0
};
int optres = neigh_options(f, &opt, PICO_ND_OPT_LLADDR_TGT);
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (optres < 0) { /* Malformed packet: option field cannot be processed. */
return -1;
}
#ifdef PICO_SUPPORT_6LOWPAN
if (PICO_DEV_IS_6LOWPAN(f->dev)) {
/* 6LoWPAN: parse Address Registration Comfirmation(nothing on success, remove link on failure) */
pico_6lp_nd_neigh_adv_process(f);
}
#endif
/* Check if there's a NCE in the cache */
n = pico_nd_find_neighbor(&icmp6_hdr->msg.info.neigh_adv.target);
if (!n) {
return 0;
}
if ((optres == 0) || IS_OVERRIDE(icmp6_hdr) || (pico_ipv6_neighbor_compare_stored(n, &opt, f->dev) == 0)) {
neigh_adv_reconfirm_router_option(n, IS_ROUTER(icmp6_hdr));
}
if ((optres > 0) && (n->state == PICO_ND_STATE_INCOMPLETE)) {
neigh_adv_process_incomplete(n, f, &opt);
return 0;
}
if (optres > 0)
return neigh_adv_reconfirm(n, &opt, icmp6_hdr, f->dev);
else
return neigh_adv_reconfirm_no_tlla(n, icmp6_hdr);
}
static struct pico_ipv6_neighbor *pico_ipv6_neighbor_from_sol_new(struct pico_ip6 *ip, struct pico_icmp6_opt_lladdr *opt, struct pico_device *dev)
{
size_t len = pico_hw_addr_len(dev, opt);
struct pico_ipv6_neighbor *n = NULL;
n = pico_nd_add(ip, dev);
if (!n)
return NULL;
memcpy(n->hwaddr.data, opt->addr.data, len);
memset(n->hwaddr.data + len, 0, sizeof(union pico_hw_addr) - len);
n->state = PICO_ND_STATE_STALE;
pico_ipv6_nd_queued_trigger();
return n;
}
static void pico_ipv6_neighbor_from_unsolicited(struct pico_frame *f)
{
struct pico_ipv6_neighbor *n = NULL;
struct pico_icmp6_opt_lladdr opt = {
0
};
struct pico_ipv6_hdr *ip = (struct pico_ipv6_hdr *)f->net_hdr;
int valid_lladdr = neigh_options(f, &opt, PICO_ND_OPT_LLADDR_SRC);
if (!pico_ipv6_is_unspecified(ip->src.addr) && (valid_lladdr > 0)) {
n = pico_nd_find_neighbor(&ip->src);
if (!n) {
n = pico_ipv6_neighbor_from_sol_new(&ip->src, &opt, f->dev);
} else if (memcmp(opt.addr.data, n->hwaddr.data, pico_hw_addr_len(f->dev, &opt))) {
pico_ipv6_neighbor_update(n, &opt, f->dev);
n->state = PICO_ND_STATE_STALE;
pico_ipv6_nd_queued_trigger();
pico_nd_new_expire_time(n);
}
if (!n)
return;
}
}
static int neigh_sol_detect_dad(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
struct pico_ipv6_hdr *ipv6_hdr = NULL;
struct pico_ipv6_link *link = NULL;
ipv6_hdr = (struct pico_ipv6_hdr *)f->net_hdr;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (!f->dev->mode) {
link = pico_ipv6_link_istentative(&icmp6_hdr->msg.info.neigh_adv.target);
if (link) {
if (pico_ipv6_is_unicast(&ipv6_hdr->src))
{
/* RFC4862 5.4.3 : sender is performing address resolution,
* our address is not yet valid, discard silently.
*/
dbg("DAD:Sender performing AR\n");
}
else if (pico_ipv6_is_unspecified(ipv6_hdr->src.addr) &&
!pico_ipv6_is_allhosts_multicast(ipv6_hdr->dst.addr))
{
/* RFC4862 5.4.3 : sender is performing DaD */
dbg("DAD:Sender performing DaD\n");
ipv6_duplicate_detected(link);
}
return 0;
}
}
return -1; /* Current link is not tentative */
}
static int neigh_sol_process(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
struct pico_ipv6_link *link = NULL;
int valid_lladdr;
struct pico_icmp6_opt_lladdr opt = {
0
};
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
valid_lladdr = neigh_options(f, &opt, PICO_ND_OPT_LLADDR_SRC);
pico_ipv6_neighbor_from_unsolicited(f);
if (!f->dev->mode && !valid_lladdr && (0 == neigh_sol_detect_dad(f)))
return 0;
#ifdef PICO_SUPPORT_6LOWPAN
else if (PICO_DEV_IS_6LOWPAN(f->dev)) {
nd_dbg("[6LP-ND] Received Address Registration Option\n");
neigh_sol_detect_dad_6lp(f);
}
#endif
if (valid_lladdr < 0)
return -1; /* Malformed packet. */
link = pico_ipv6_link_get(&icmp6_hdr->msg.info.neigh_adv.target);
if (!link) { /* Not for us. */
return -1;
}
pico_icmp6_neighbor_advertisement(f, &icmp6_hdr->msg.info.neigh_adv.target);
return 0;
}
static int icmp6_initial_checks(struct pico_frame *f)
{
/* Common "step 0" validation */
struct pico_ipv6_hdr *ipv6_hdr = NULL;
struct pico_icmp6_hdr *icmp6_hdr = NULL;
ipv6_hdr = (struct pico_ipv6_hdr *)f->net_hdr;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
/* RFC4861 - 7.1.2 :
* - The IP Hop Limit field has a value of 255, i.e., the packet
* could not possibly have been forwarded by a router.
* - ICMP Checksum is valid.
* - ICMP Code is 0.
*/
if (ipv6_hdr->hop != 255 || pico_icmp6_checksum(f) != 0 || icmp6_hdr->code != 0)
return -1;
return 0;
}
static int neigh_adv_option_len_validity_check(struct pico_frame *f)
{
/* Step 4 validation */
struct pico_icmp6_hdr *icmp6_hdr = NULL;
uint8_t *opt;
int optlen = f->transport_len - PICO_ICMP6HDR_NEIGH_ADV_SIZE;
/* RFC4861 - 7.1.2 :
* - All included options have a length that is greater than zero.
*/
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
opt = ((uint8_t *)&icmp6_hdr->msg.info.neigh_adv) + sizeof(struct neigh_adv_s);
while(optlen > 0) {
int opt_size = (opt[1] << 3);
if (opt_size == 0)
return -1;
opt = opt + opt_size;
optlen -= opt_size;
}
return 0;
}
static int neigh_adv_mcast_validity_check(struct pico_frame *f)
{
/* Step 3 validation */
struct pico_ipv6_hdr *ipv6_hdr = NULL;
struct pico_icmp6_hdr *icmp6_hdr = NULL;
/* RFC4861 - 7.1.2 :
* - If the IP Destination Address is a multicast address the
* Solicited flag is zero.
*/
ipv6_hdr = (struct pico_ipv6_hdr *)f->net_hdr;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (pico_ipv6_is_multicast(ipv6_hdr->dst.addr) && IS_SOLICITED(icmp6_hdr))
return -1;
return neigh_adv_option_len_validity_check(f);
}
static int neigh_adv_validity_checks(struct pico_frame *f)
{
/* Step 2 validation */
/* RFC4861 - 7.1.2:
* - ICMP length (derived from the IP length) is 24 or more octets.
*/
if (f->transport_len < PICO_ICMP6HDR_NEIGH_ADV_SIZE)
return -1;
return neigh_adv_mcast_validity_check(f);
}
static int neigh_sol_mcast_validity_check(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (pico_ipv6_is_solnode_multicast(icmp6_hdr->msg.info.neigh_sol.target.addr, f->dev) == 0)
return -1;
return 0;
}
static int neigh_sol_unicast_validity_check(struct pico_frame *f)
{
struct pico_ipv6_link *link;
struct pico_icmp6_hdr *icmp6_hdr = NULL;
#ifdef PICO_SUPPORT_6LOWPAN
/* Don't validate target address, the sol is always targeted at 6LBR so
* no possible interface on the 6LBR can have the same address as specified in
* the target */
if (PICO_DEV_IS_6LOWPAN(f->dev))
return 0;
#endif
link = pico_ipv6_link_by_dev(f->dev);
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
while(link) {
/* RFC4861, 7.2.3:
*
* - The Target Address is a "valid" unicast or anycast address
* assigned to the receiving interface [ADDRCONF],
* - The Target Address is a unicast or anycast address for which the
* node is offering proxy service, or
* - The Target Address is a "tentative" address on which Duplicate
* Address Detection is being performed
*/
if (pico_ipv6_compare(&link->address, &icmp6_hdr->msg.info.neigh_sol.target) == 0)
return 0;
link = pico_ipv6_link_by_dev_next(f->dev, link);
}
return -1;
}
static int neigh_sol_validate_unspec(struct pico_frame *f)
{
/* RFC4861, 7.1.1:
*
* - If the IP source address is the unspecified address, the IP
* destination address is a solicited-node multicast address.
*
* - If the IP source address is the unspecified address, there is no
* source link-layer address option in the message.
*
*/
struct pico_ipv6_hdr *hdr = (struct pico_ipv6_hdr *)(f->net_hdr);
struct pico_icmp6_opt_lladdr opt = {
0
};
int valid_lladdr = neigh_options(f, &opt, PICO_ND_OPT_LLADDR_SRC);
if (!f->dev->mode && pico_ipv6_is_solnode_multicast(hdr->dst.addr, f->dev) == 0) {
return -1;
}
if (valid_lladdr) {
return -1;
}
return 0;
}
static int neigh_sol_validity_checks(struct pico_frame *f)
{
/* Step 2 validation */
struct pico_icmp6_hdr *icmp6_hdr = NULL;
struct pico_ipv6_hdr *hdr = (struct pico_ipv6_hdr *)(f->net_hdr);
if (f->transport_len < PICO_ICMP6HDR_NEIGH_ADV_SIZE)
return -1;
if ((pico_ipv6_is_unspecified(hdr->src.addr)) && (neigh_sol_validate_unspec(f) < 0))
{
return -1;
}
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (pico_ipv6_is_multicast(icmp6_hdr->msg.info.neigh_adv.target.addr)) {
return neigh_sol_mcast_validity_check(f);
}
return neigh_sol_unicast_validity_check(f);
}
static int router_adv_validity_checks(struct pico_frame *f)
{
/* Step 2 validation */
if (f->transport_len < PICO_ICMP6HDR_ROUTER_ADV_SIZE)
return -1;
return 0;
}
static int neigh_adv_checks(struct pico_frame *f)
{
/* Step 1 validation */
if (icmp6_initial_checks(f) < 0)
return -1;
return neigh_adv_validity_checks(f);
}
/*MARK*/
#ifdef PICO_SUPPORT_6LOWPAN
static void pico_6lp_nd_unreachable_gateway(struct pico_ip6 *a)
{
struct pico_ipv6_route *route = NULL;
struct pico_ipv6_link *local = NULL;
struct pico_tree_node *node = NULL;
struct pico_device *dev = NULL;
/* RFC6775, 5.3:
* ... HOSTS need to intelligently retransmit RSs when one of its
* default routers becomes unreachable ...
*/
pico_tree_foreach(node, &Device_tree) {
if (PICO_DEV_IS_6LOWPAN(dev) && (!dev->hostvars.routing)) {
/* Check if there's a gateway configured */
route = pico_ipv6_gateway_by_dev(dev);
while (route) {
if (0 == pico_ipv6_compare(&route->gateway, a)) {
local = pico_ipv6_linklocal_get(dev);
pico_6lp_nd_start_soliciting(local, route);
break;
}
route = pico_ipv6_gateway_by_dev_next(dev, route);
}
}
}
}
static int pico_6lp_nd_validate_sol_aro(struct pico_icmp6_opt_aro *aro)
{
if (aro->len != 2 || aro->status != 0)
return -1;
return 0;
}
static int pico_6lp_nd_validate_adv_aro(struct pico_device *dev, struct pico_icmp6_opt_aro *aro, uint8_t *status)
{
union pico_ll_addr addr, eui;
/* RFC6775 - 5.5.2 :
* - If the length field is not two, the option is silently ignored.
* - If the EUI-64 field does not match the EUI-64 of the interface,
* the option is silently ignored.
*/
if (aro->len != 2)
return -1;
/* TODO: Update to abstract address, e.g. remove dependency of '.pan' */
eui.pan.addr._ext = aro->eui64;
eui.pan.mode = AM_6LOWPAN_EXT;
addr.pan.addr._ext = ((struct pico_6lowpan_info *)dev->eth)->addr_ext;
addr.pan.mode = AM_6LOWPAN_EXT;
if (dev && pico_6lowpan_lls[dev->mode].addr_cmp) {
if (pico_6lowpan_lls[dev->mode].addr_cmp(&addr, &eui))
return -1;
} else {
return -1;
}
*status = aro->status;
return 0;
}
/* Deregisters a link from all default gateways */
static void pico_6lp_nd_deregister(struct pico_ipv6_link *l)
{
struct pico_ipv6_route *gw = pico_ipv6_gateway_by_dev(l->dev);
while (gw) {
pico_icmp6_neighbor_solicitation(l->dev, &l->address, PICO_ICMP6_ND_DEREGISTER, &gw->gateway);
gw = pico_ipv6_gateway_by_dev_next(l->dev, gw);
}
}
/* Retransmits neighbors solicitations with address registration if ARO is not acknowledged */
static void pico_6lp_nd_register_try(pico_time now, void *arg)
{
struct pico_ipv6_link *l = arg;
struct pico_ipv6_route *gw = pico_ipv6_gateway_by_dev(l->dev);
IGNORE_PARAMETER(now);
while (gw) {
l->istentative = 1;
pico_icmp6_neighbor_solicitation(l->dev, &l->address, PICO_ICMP6_ND_DAD, &gw->gateway);
gw = pico_ipv6_gateway_by_dev_next(l->dev, gw);
}
pico_timer_add(l->dev->hostvars.retranstime, pico_6lp_nd_register_try, l);
}
/* Tries to register a link with one or more of its default routers */
void pico_6lp_nd_register(struct pico_ipv6_link *link)
{
/* RFC6775: When a host has configured a non-link-local IPv6 address, it registers that
* address with one or more of its default routers using the Address Registration
* Option (ARO) in an NS message. */
pico_6lp_nd_register_try(PICO_TIME_MS(), link);
}
/* Check if there are default routers configured. If not, sent a router solicitation */
static void pico_6lp_nd_do_solicit(pico_time now, void *arg)
{
struct pico_ipv6_route *gw = arg;
struct pico_ip6 *dst = NULL;
IGNORE_PARAMETER(now);
if (!pico_ipv6_gateway_by_dev(gw->link->dev) && !gw->link->dev->hostvars.routing) {
/* If the solicitation is to be sent unicast */
if (!pico_ipv6_is_unspecified(gw->gateway.addr) && gw->retrans < MAX_RTR_SOLICITATIONS)
dst = &gw->gateway;
/* Exponential backoff */
if (++gw->retrans == MAX_RTR_SOLICITATIONS) {
gw->backoff <<= 1;
if (gw->backoff >= MAX_RTR_SOLICITATION_INTERVAL)
gw->backoff = (pico_time)MAX_RTR_SOLICITATION_INTERVAL;
}
/* If router list is empty, send router solicitation */
pico_icmp6_router_solicitation(gw->link->dev, &gw->link->address, dst);
/* Apply exponential retransmission timer, see RFC6775 5.3 */
pico_timer_add(gw->backoff, pico_6lp_nd_do_solicit, gw);
nd_dbg("[6LP-ND]$ No default routers configured, soliciting\n");
} else {
PICO_FREE(gw);
}
}
/* Start transmitting repetitive router solicitations */
int pico_6lp_nd_start_soliciting(struct pico_ipv6_link *l, struct pico_ipv6_route *gw)
{
struct pico_ipv6_route *dummy = PICO_ZALLOC(sizeof(struct pico_ipv6_route));
struct pico_ip6 *dst = NULL;
if (dummy) {
if (gw) { // If the router solicitation has to be sent unicast ...
dst = &gw->gateway; // ... the gateway is the destination
memcpy(dummy->gateway.addr, gw->gateway.addr, PICO_SIZE_IP6); // and should be retrievable in the timer event
}
dummy->link = l; // the link that has to be reconfirmed as well.
/* If router list is empty, send router solicitation */
pico_icmp6_router_solicitation(l->dev, &l->address, dst);
if (!l->dev->hostvars.routing) {
dummy->retrans = 0;
dummy->backoff = RTR_SOLICITATION_INTERVAL;
if (!pico_timer_add(dummy->backoff, pico_6lp_nd_do_solicit, dummy)) {
PICO_FREE(dummy);
return -1;
}
} else {
PICO_FREE(dummy);
}
return 0;
}
return -1;
}
/* Validate Neighbor advertisement mesaage */
static int pico_6lp_nd_neigh_adv_validate(struct pico_frame *f, uint8_t *status)
{
struct pico_icmp6_hdr *icmp = (struct pico_icmp6_hdr *)f->transport_hdr;
struct pico_icmp6_opt_aro *aro = (struct pico_icmp6_opt_aro *)((uint8_t *)&icmp->msg.info.neigh_adv + sizeof(struct neigh_sol_s));
struct pico_ipv6_hdr *ip = (struct pico_ipv6_hdr *)f->net_hdr;
/* 6LP: Target address cannot be MCAST and the Source IP-address cannot be UNSPECIFIED or MCAST */
if (pico_ipv6_is_multicast(icmp->msg.info.neigh_adv.target.addr) || pico_ipv6_is_unspecified(ip->src.addr) ||
pico_ipv6_is_multicast(ip->src.addr))
return -1;
return pico_6lp_nd_validate_adv_aro(f->dev, aro, status);
}
/* Process neighbor advertisement */
static int pico_6lp_nd_neigh_adv_process(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp = (struct pico_icmp6_hdr *)f->transport_hdr;
struct pico_ipv6_hdr *hdr = (struct pico_ipv6_hdr *)f->net_hdr;
struct pico_ipv6_link *l = NULL;
struct pico_ip6 zero = {
.addr = {0}
};
uint8_t status = 0;
if (pico_6lp_nd_neigh_adv_validate(f, &status)) {
return -1;
} else {
l = pico_ipv6_link_get(&icmp->msg.info.neigh_adv.target);
if (l)
l->istentative = 0;
else
return -1;
/* Globally routable address has been registered @ 6LoWPAN Border Router */
if (1 == status) { // Duplicate address detected
nd_dbg("[6LP-ND]: Registering routable address failed, removing link...\n");
ipv6_duplicate_detected(l);
return -1;
} else if (2 == status) { // Router's NCE is full, remove router from default router list
pico_ipv6_route_del(zero, zero, hdr->src, 10, l);
pico_6lp_nd_start_soliciting(pico_ipv6_linklocal_get(l->dev), NULL);
} else { // Registration success
nd_dbg("[6LP-ND]: Registering routable address succeeded!\n");
}
}
return 0;
}
/* Add a new 6LoWPAN neighbor with lifetime from ARO */
static struct pico_ipv6_neighbor *pico_nd_add_6lp(struct pico_ip6 naddr, struct pico_icmp6_opt_aro *aro, struct pico_device *dev)
{
struct pico_ipv6_neighbor *new = NULL;
if ((new = pico_nd_add(&naddr, dev))) {
new->expire = PICO_TIME_MS() + (pico_time)(ONE_MINUTE * aro->lifetime);
dbg("ARO Lifetime: %d minutes\n", aro->lifetime);
} else {
return NULL;
}
return new;
}
/* RFC6775 §6.5.2. Returning Address Registration Errors */
static int neigh_sol_dad_reply(struct pico_frame *sol, struct pico_icmp6_opt_lladdr *sllao, struct pico_icmp6_opt_aro *aro, uint8_t status)
{
uint8_t sllao_len = (uint8_t)(sllao->len * 8);
struct pico_icmp6_hdr *icmp = NULL;
struct pico_frame *adv = pico_frame_copy(sol);
struct pico_ip6 ll = {{0xfe,0x80,0,0,0,0,0,0, 0,0,0,0,0,0,0,0}};
size_t len = pico_hw_addr_len(sol->dev, sllao);
union pico_ll_addr lladdr;
if (!adv) {
return -1;
} else {
icmp = (struct pico_icmp6_hdr *)adv->transport_hdr;
/* Set the status of the Address Registration */
aro->status = status;
if (PICO_DEV_IS_6LOWPAN(sol->dev)) {
memcpy(lladdr.pan.addr.data, aro->eui64.addr, len);
lladdr.pan.mode = (len == SIZE_6LOWPAN_EXT) ? AM_6LOWPAN_EXT : AM_6LOWPAN_SHORT;
if (pico_6lowpan_lls[sol->dev->mode].addr_iid)
pico_6lowpan_lls[sol->dev->mode].addr_iid(ll.addr + 8, &lladdr);
}
/* Remove the SLLAO from the frame */
memmove(((uint8_t *)&icmp->msg.info.neigh_sol) + sizeof(struct neigh_sol_s), ((uint8_t *)&icmp->msg.info.neigh_sol) + sizeof(struct neigh_sol_s) + sllao_len, (size_t)(aro->len * 8));
adv->transport_len = (uint16_t)(adv->transport_len - sllao_len);
adv->len = (uint16_t)(adv->len - sllao_len);
/* I'm a router, and it's always solicited */
icmp->msg.info.neigh_adv.rsor = 0xE0;
/* Set the ICMPv6 message type to Neighbor Advertisements */
icmp->type = PICO_ICMP6_NEIGH_ADV;
icmp->code = 0;
icmp->crc = pico_icmp6_checksum(adv);
pico_ipv6_frame_push(adv, NULL, &ll, PICO_PROTO_ICMP6, 0);
return 0;
}
}
/* RFC6775 §6.5.1. Checking for Duplicates */
static int neigh_sol_detect_dad_6lp(struct pico_frame *f)
{
struct pico_ipv6_neighbor *n = NULL;
struct pico_icmp6_opt_lladdr *sllao = NULL;
struct pico_icmp6_hdr *icmp = NULL;
struct pico_icmp6_opt_aro *aro = NULL;
size_t len = 0;
icmp = (struct pico_icmp6_hdr *)f->transport_hdr;
sllao = (struct pico_icmp6_opt_lladdr *)((uint8_t *)&icmp->msg.info.neigh_sol + sizeof(struct neigh_sol_s));
aro = (struct pico_icmp6_opt_aro *)(((uint8_t *)&icmp->msg.info.neigh_sol) + sizeof(struct neigh_sol_s) + (sllao->len * 8));
/* Validate Address Registration Option */
if (pico_6lp_nd_validate_sol_aro(aro))
return -1;
/* See RFC6775 $6.5.1: Checking for duplicates */
if (!(n = pico_nd_find_neighbor(&icmp->msg.info.neigh_sol.target))) {
/* No dup, add neighbor to cache */
if (pico_nd_add_6lp(icmp->msg.info.neigh_sol.target, aro, f->dev))
neigh_sol_dad_reply(f, sllao, aro, ICMP6_ARO_SUCCES);
else /* No dup, but neighbor cache is full */
neigh_sol_dad_reply(f, sllao, aro, ICMP6_ARO_FULL);
return 0;
} else {
if (!aro->lifetime) {
pico_tree_delete(&NCache, n);
PICO_FREE(n);
neigh_sol_dad_reply(f, sllao, aro, ICMP6_ARO_SUCCES);
return 0;
}
/* Check if hwaddr differs */
len = pico_hw_addr_len(f->dev, sllao);
if (memcmp(sllao->addr.data, n->hwaddr.data, len) == 0) {
n->expire = PICO_TIME_MS() + (pico_time)(ONE_MINUTE * aro->lifetime);
neigh_sol_dad_reply(f, sllao, aro, ICMP6_ARO_DUP);
}
return 0;
}
}
static int router_options(struct pico_frame *f, struct pico_icmp6_opt_lladdr *opt, uint8_t expected_opt)
{
/* RFC 4861 $6.1
* The contents of any defined options that are not specified to be used
* with Router Solicitation messages MUST be ignored and the packet
* processed as normal. The only defined option that may appear is the
* Source Link-Layer Address option.
*/
struct pico_icmp6_hdr *icmp6_hdr = NULL;
uint8_t *options = NULL;
int optlen = 0;
int len = 0;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
optlen = f->transport_len - PICO_ICMP6HDR_ROUTER_SOL_SIZE;
if (optlen)
options = ((uint8_t *)&icmp6_hdr->msg.info.router_sol) + sizeof(struct router_sol_s);
return nd_options(options, opt, expected_opt, optlen, len);
}
static int router_sol_validity_checks(struct pico_frame *f)
{
struct pico_ipv6_hdr *hdr = (struct pico_ipv6_hdr *)(f->net_hdr);
struct pico_icmp6_opt_lladdr opt = { 0 };
int sllao_present = 0;
/* Step 2 validation */
if (f->transport_len < PICO_ICMP6HDR_ROUTER_SOL_SIZE_6LP)
return -1;
/* RFC4861, 6.1.1:
* - If the IP source address is the unspecified address, there is no
* source link-layer address option in the message.
*/
/* Check for SLLAO if the IP source address is UNSPECIFIED */
sllao_present = router_options(f, &opt, PICO_ND_OPT_LLADDR_SRC);
if (pico_ipv6_is_unspecified(hdr->src.addr)) {
/* Frame is not valid when SLLAO is present if IP6-SRC is UNSPEC. */
if (sllao_present) {
return -1;
}
} else {
/* Frame is not valid when no SLLAO if present if there's a IP6-SRC */
if (sllao_present <= 0) {
return -1;
}
}
return 0;
}
static int router_sol_checks(struct pico_frame *f)
{
/* Step 1 validation */
if (icmp6_initial_checks(f) < 0)
return -1;
return router_sol_validity_checks(f);
}
static int router_sol_process(struct pico_frame *f)
{
struct pico_ipv6_hdr *hdr = NULL;
/* Determine if i'm a 6LBR, if i'm not, can't do anything with a router solicitation */
if (!f->dev->hostvars.routing)
return -1;
nd_dbg("[6LBR]: Processing router solicitation...\n");
/* Router solicitation message validation */
if (router_sol_checks(f) < 0)
return -1;
/* Maybe create a tentative NCE? No, will do it later */
/* Send a router advertisement via unicast to requesting host */
hdr = (struct pico_ipv6_hdr *)f->net_hdr;
return pico_icmp6_router_advertisement(f->dev, &hdr->src);
}
#endif /* PICO_SUPPORT_6LOWPAN */
static int pico_nd_router_sol_recv(struct pico_frame *f)
{
#ifdef PICO_SUPPORT_6LOWPAN
/* 6LoWPAN: reply on explicit router solicitations via unicast */
if (PICO_DEV_IS_6LOWPAN(f->dev))
return router_sol_process(f);
#endif
pico_ipv6_neighbor_from_unsolicited(f);
/* Host only: router solicitation is discarded. */
return 0;
}
static int radv_process(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
uint8_t *nxtopt, *opt_start;
struct pico_ipv6_link *link;
uint32_t pref_lifetime = 0;
struct pico_ipv6_hdr *hdr;
struct pico_ip6 zero = {
.addr = {0}
};
int optlen;
#ifdef PICO_SUPPORT_6LOWPAN
int sllao = 0;
#endif
hdr = (struct pico_ipv6_hdr *)f->net_hdr;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
optlen = f->transport_len - PICO_ICMP6HDR_ROUTER_ADV_SIZE;
opt_start = ((uint8_t *)&icmp6_hdr->msg.info.router_adv) + sizeof(struct router_adv_s);
nxtopt = opt_start;
while (optlen > 0) {
uint8_t *type = (uint8_t *)nxtopt;
switch (*type) {
case PICO_ND_OPT_PREFIX:
{
pico_time now = PICO_TIME_MS();
struct pico_icmp6_opt_prefix *prefix =
(struct pico_icmp6_opt_prefix *) nxtopt;
/* RFC4862 5.5.3 */
/* a) If the Autonomous flag is not set, silently ignore the Prefix
* Information option.
*/
if (prefix->aac == 0)
goto ignore_opt_prefix;
/* b) If the prefix is the link-local prefix, silently ignore the
* Prefix Information option
*/
if (pico_ipv6_is_linklocal(prefix->prefix.addr))
goto ignore_opt_prefix;
/* c) If the preferred lifetime is greater than the valid lifetime,
* silently ignore the Prefix Information option
*/
pref_lifetime = long_be(prefix->pref_lifetime);
if (pref_lifetime > long_be(prefix->val_lifetime))
goto ignore_opt_prefix;
#ifdef PICO_SUPPORT_6LOWPAN
/* RFC6775 (6LoWPAN): Should the host erroneously receive a PIO with the L (on-link)
* flag set, then that PIO MUST be ignored.
*/
if (PICO_DEV_IS_6LOWPAN(f->dev) && prefix->onlink)
goto ignore_opt_prefix;
#endif
if (prefix->val_lifetime == 0)
goto ignore_opt_prefix;
if (prefix->prefix_len != 64) {
return -1;
}
/* Refresh lifetime of a prefix */
link = pico_ipv6_prefix_configured(&prefix->prefix);
if (link) {
pico_ipv6_lifetime_set(link, now + (1000 * (pico_time)(long_be(prefix->val_lifetime))));
goto ignore_opt_prefix;
}
/* Configure a an non linklocal IPv6 address */
link = pico_ipv6_link_add_local(f->dev, &prefix->prefix);
if (link) {
pico_ipv6_lifetime_set(link, now + (1000 * (pico_time)(long_be(prefix->val_lifetime))));
/* Add a default gateway to the default routers list with source of RADV */
pico_ipv6_route_add(zero, zero, hdr->src, 10, link);
#ifdef PICO_SUPPORT_6LOWPAN
if (PICO_DEV_IS_6LOWPAN(f->dev)) {
pico_6lp_nd_register(link);
}
#endif
}
ignore_opt_prefix:
optlen -= (prefix->len << 3);
nxtopt += (prefix->len << 3);
}
break;
case PICO_ND_OPT_LLADDR_SRC:
{
struct pico_icmp6_opt_lladdr *lladdr_src =
(struct pico_icmp6_opt_lladdr *) nxtopt;
#ifdef PICO_SUPPORT_6LOWPAN
sllao = 1; // RFC6775 (6LoWPAN): An SLLAO MUST be included in the RA.
#endif
optlen -= (lladdr_src->len << 3);
nxtopt += (lladdr_src->len << 3);
}
break;
case PICO_ND_OPT_MTU:
{
struct pico_icmp6_opt_mtu *mtu =
(struct pico_icmp6_opt_mtu *) nxtopt;
/* Skip this */
optlen -= (mtu->len << 3);
nxtopt += (mtu->len << 3);
}
break;
case PICO_ND_OPT_REDIRECT:
{
struct pico_icmp6_opt_redirect *redirect =
(struct pico_icmp6_opt_redirect *) nxtopt;
/* Skip this */
optlen -= (redirect->len << 3);
nxtopt += (redirect->len << 3);
}
break;
case PICO_ND_OPT_RDNSS:
{
struct pico_icmp6_opt_rdnss *rdnss =
(struct pico_icmp6_opt_rdnss *) nxtopt;
/* Skip this */
optlen -= (rdnss->len << 3);
nxtopt += (rdnss->len << 3);
}
break;
#ifdef PICO_SUPPORT_6LOWPAN
case PICO_ND_OPT_6CO:
{
struct pico_icmp6_opt_6co *co = (struct pico_icmp6_opt_6co *)nxtopt;
#ifdef PICO_6LOWPAN_IPHC_ENABLED
if (PICO_DEV_IS_6LOWPAN(f->dev)) {
struct pico_ip6 prefix;
memcpy(prefix.addr, (uint8_t *)&co->prefix, (size_t)(co->len - 1) << 3);
ctx_update(prefix, co->id, co->clen, co->lifetime, co->c, f->dev);
}
#endif
optlen -= (co->len << 3);
nxtopt += (co->len << 3);
}
break;
case PICO_ND_OPT_ABRO:
{
struct pico_icmp6_opt_abro *abro = (struct pico_icmp6_opt_abro *)nxtopt;
/* TODO: Process */
optlen -= (abro->len << 3);
nxtopt += (abro->len << 3);
}
break;
#endif
default:
pico_icmp6_parameter_problem(f, PICO_ICMP6_PARAMPROB_IPV6OPT,
(uint32_t)sizeof(struct pico_ipv6_hdr) + (uint32_t)PICO_ICMP6HDR_ROUTER_ADV_SIZE + (uint32_t)(nxtopt - opt_start));
return -1;
}
}
#ifdef PICO_SUPPORT_6LOWPAN
if (PICO_DEV_IS_6LOWPAN(f->dev) && !sllao) {
return -1;
}
#endif
if (icmp6_hdr->msg.info.router_adv.retrans_time != 0u) {
f->dev->hostvars.retranstime = long_be(icmp6_hdr->msg.info.router_adv.retrans_time);
}
return 0;
}
static int pico_nd_router_adv_recv(struct pico_frame *f)
{
if (icmp6_initial_checks(f) < 0)
return -1;
if (router_adv_validity_checks(f) < 0)
return -1;
pico_ipv6_neighbor_from_unsolicited(f);
return radv_process(f);
}
static int pico_nd_neigh_sol_recv(struct pico_frame *f)
{
if (icmp6_initial_checks(f) < 0)
return -1;
if (neigh_sol_validity_checks(f) < 0)
return -1;
return neigh_sol_process(f);
}
static int pico_nd_neigh_adv_recv(struct pico_frame *f)
{
struct pico_icmp6_hdr *icmp6_hdr = NULL;
struct pico_ipv6_link *link = NULL;
icmp6_hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
if (neigh_adv_checks(f) < 0) {
return -1;
}
/* ETH: Target address belongs to a tentative link on this device, DaD detected a dup */
link = pico_ipv6_link_istentative(&icmp6_hdr->msg.info.neigh_adv.target);
if (link && !link->dev->mode)
ipv6_duplicate_detected(link);
return neigh_adv_process(f);
}
static int pico_nd_redirect_recv(struct pico_frame *f)
{
pico_ipv6_neighbor_from_unsolicited(f);
/* TODO */
return 0;
}
static void pico_ipv6_nd_timer_elapsed(pico_time now, struct pico_ipv6_neighbor *n)
{
(void)now;
switch(n->state) {
case PICO_ND_STATE_INCOMPLETE:
/* intentional fall through */
case PICO_ND_STATE_PROBE:
if (n->failure_count > PICO_ND_MAX_SOLICIT) {
pico_ipv6_nd_unreachable(&n->address);
pico_tree_delete(&NCache, n);
PICO_FREE(n);
return;
}
n->expire = 0ull;
pico_nd_discover(n);
break;
case PICO_ND_STATE_REACHABLE:
n->state = PICO_ND_STATE_STALE;
/* dbg("IPv6_ND: neighbor expired!\n"); */
return;
case PICO_ND_STATE_STALE:
break;
case PICO_ND_STATE_DELAY:
n->expire = 0ull;
n->state = PICO_ND_STATE_PROBE;
break;
default:
dbg("IPv6_ND: neighbor in wrong state!\n");
}
pico_nd_new_expire_time(n);
}
static void pico_ipv6_nd_timer_callback(pico_time now, void *arg)
{
struct pico_tree_node *index = NULL, *_tmp = NULL;
struct pico_ipv6_neighbor *n;
(void)arg;
pico_tree_foreach_safe(index, &NCache, _tmp)
{
n = index->keyValue;
if ( now > n->expire ) {
pico_ipv6_nd_timer_elapsed(now, n);
}
}
if (!pico_timer_add(200, pico_ipv6_nd_timer_callback, NULL)) {
dbg("IPV6 ND: Failed to start callback timer\n");
/* TODO no idea what consequences this has */
}
}
#define PICO_IPV6_ND_MIN_RADV_INTERVAL (5000)
#define PICO_IPV6_ND_MAX_RADV_INTERVAL (15000)
static void pico_ipv6_nd_ra_timer_callback(pico_time now, void *arg)
{
struct pico_tree_node *devindex = NULL;
struct pico_tree_node *rindex = NULL;
struct pico_device *dev;
struct pico_ipv6_route *rt;
struct pico_ip6 nm64 = { {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0 } };
pico_time next_timer_expire = 0u;
(void)arg;
(void)now;
pico_tree_foreach(rindex, &IPV6Routes)
{
rt = rindex->keyValue;
if (pico_ipv6_compare(&nm64, &rt->netmask) == 0) {
pico_tree_foreach(devindex, &Device_tree) {
dev = devindex->keyValue;
/* Do not send periodic router advertisements when there aren't 2 interfaces from and to the device can route */
if ((!pico_ipv6_is_linklocal(rt->dest.addr)) && dev->hostvars.routing && (rt->link)
&& (dev != rt->link->dev) && !PICO_DEV_IS_6LOWPAN(dev)) {
pico_icmp6_router_advertisement(dev, &rt->dest);
}
}
}
}
next_timer_expire = PICO_IPV6_ND_MIN_RADV_INTERVAL + (pico_rand() % (PICO_IPV6_ND_MAX_RADV_INTERVAL - PICO_IPV6_ND_MIN_RADV_INTERVAL));
if (!pico_timer_add(next_timer_expire, pico_ipv6_nd_ra_timer_callback, NULL)) {
dbg("IPv6 ND: Failed to start callback timer\n");
/* TODO no idea what consequences this has */
}
}
/* Public API */
struct pico_eth *pico_ipv6_get_neighbor(struct pico_frame *f)
{
struct pico_ipv6_hdr *hdr = NULL;
struct pico_ipv6_link *l = NULL;
if (!f)
return NULL;
hdr = (struct pico_ipv6_hdr *)f->net_hdr;
/* If we are still probing for Duplicate Address, abort now. */
if (pico_ipv6_link_istentative(&hdr->src))
return NULL;
/* address belongs to ourselves? */
l = pico_ipv6_link_get(&hdr->dst);
if (l && !l->dev->mode)
return &l->dev->eth->mac;
else if (l && PICO_DEV_IS_6LOWPAN(l->dev))
return (struct pico_eth *)l->dev->eth;
return pico_nd_get(&hdr->dst, f->dev);
}
void pico_ipv6_nd_postpone(struct pico_frame *f)
{
int i;
static int last_enq = -1;
for (i = 0; i < PICO_ND_MAX_FRAMES_QUEUED; i++)
{
if (!frames_queued_v6[i]) {
frames_queued_v6[i] = f;
last_enq = i;
return;
}
}
/* Overwrite the oldest frame in the buffer */
if (++last_enq >= PICO_ND_MAX_FRAMES_QUEUED) {
last_enq = 0;
}
if (frames_queued_v6[last_enq])
pico_frame_discard(frames_queued_v6[last_enq]);
frames_queued_v6[last_enq] = f;
}
int pico_ipv6_nd_recv(struct pico_frame *f)
{
struct pico_icmp6_hdr *hdr = (struct pico_icmp6_hdr *)f->transport_hdr;
int ret = -1;
switch(hdr->type) {
case PICO_ICMP6_ROUTER_SOL:
nd_dbg("ICMP6: received ROUTER SOL\n");
ret = pico_nd_router_sol_recv(f);
break;
case PICO_ICMP6_ROUTER_ADV:
nd_dbg("ICMP6: received ROUTER ADV\n");
ret = pico_nd_router_adv_recv(f);
break;
case PICO_ICMP6_NEIGH_SOL:
nd_dbg("ICMP6: received NEIGH SOL\n");
ret = pico_nd_neigh_sol_recv(f);
break;
case PICO_ICMP6_NEIGH_ADV:
nd_dbg("ICMP6: received NEIGH ADV\n");
ret = pico_nd_neigh_adv_recv(f);
break;
case PICO_ICMP6_REDIRECT:
ret = pico_nd_redirect_recv(f);
break;
}
pico_frame_discard(f);
return ret;
}
void pico_ipv6_nd_init(void)
{
uint32_t timer_cb = 0, ra_timer_cb = 0;
timer_cb = pico_timer_add(200, pico_ipv6_nd_timer_callback, NULL);
if (!timer_cb) {
nd_dbg("IPv6 ND: Failed to start callback timer\n");
return;
}
ra_timer_cb = pico_timer_add(200, pico_ipv6_nd_ra_timer_callback, NULL);
if (!ra_timer_cb) {
nd_dbg("IPv6 ND: Failed to start RA callback timer\n");
pico_timer_cancel(timer_cb);
return;
}
if (!pico_timer_add(1000, pico_ipv6_check_lifetime_expired, NULL)) {
nd_dbg("IPv6 ND: Failed to start check_lifetime timer\n");
pico_timer_cancel(timer_cb);
pico_timer_cancel(ra_timer_cb);
return;
}
}
#endif