#include <netinet/ether.h>

#include <netinet/icmp6.h>

#include <linux/if.h>

#include "sd-ndisc.h"

#include "networkd-link.h"

static int ndisc_netlink_handler(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {

_cleanup_link_unref_ Link *link = userdata;

int r;

assert(link);

assert(link->ndisc_messages > 0);

link->ndisc_messages --;

r = sd_netlink_message_get_errno(m);

if (r < 0 && r != -EEXIST) {

log_link_error_errno(link, r, "Could not set NDisc route or address: %m");

link_enter_failed(link);

}

if (link->ndisc_messages == 0) {

link->ndisc_configured = true;

link_check_ready(link);

}

return 1;

}

static void ndisc_prefix_autonomous_handler(sd_ndisc *nd, const struct in6_addr *prefix, unsigned prefixlen,

unsigned lifetime_preferred, unsigned lifetime_valid, void *userdata) {

_cleanup_address_free_ Address *address = NULL;

Link *link = userdata;

usec_t time_now;

int r;

assert(nd);

assert(link);

assert(link->network);

if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))

return;

r = address_new(&address);

if (r < 0) {

log_link_error_errno(link, r, "Could not allocate address: %m");

return;

}

assert_se(sd_event_now(link->manager->event, clock_boottime_or_monotonic(), &time_now) >= 0);

address->family = AF_INET6;

address->in_addr.in6 = *prefix;

if (in_addr_is_null(AF_INET6, (const union in_addr_union *) &link->network->ipv6_token) == 0)

memcpy(&address->in_addr.in6 + 8, &link->network->ipv6_token + 8, 8);

else {

/* see RFC4291 section 2.5.1 */

address->in_addr.in6.__in6_u.__u6_addr8[8] = link->mac.ether_addr_octet[0];

address->in_addr.in6.__in6_u.__u6_addr8[8] ^= 1 << 1;

address->in_addr.in6.__in6_u.__u6_addr8[9] = link->mac.ether_addr_octet[1];

address->in_addr.in6.__in6_u.__u6_addr8[10] = link->mac.ether_addr_octet[2];

address->in_addr.in6.__in6_u.__u6_addr8[11] = 0xff;

address->in_addr.in6.__in6_u.__u6_addr8[12] = 0xfe;

address->in_addr.in6.__in6_u.__u6_addr8[13] = link->mac.ether_addr_octet[3];

address->in_addr.in6.__in6_u.__u6_addr8[14] = link->mac.ether_addr_octet[4];

address->in_addr.in6.__in6_u.__u6_addr8[15] = link->mac.ether_addr_octet[5];

}

address->prefixlen = prefixlen;

address->flags = IFA_F_NOPREFIXROUTE;

address->cinfo.ifa_prefered = lifetime_preferred;

address->cinfo.ifa_valid = lifetime_valid;

r = address_configure(address, link, ndisc_netlink_handler, true);

if (r < 0) {

log_link_warning_errno(link, r, "Could not set SLAAC address: %m");

link_enter_failed(link);

return;

}

link->ndisc_messages ++;

}

static void ndisc_prefix_onlink_handler(sd_ndisc *nd, const struct in6_addr *prefix, unsigned prefixlen, unsigned lifetime, void *userdata) {

_cleanup_route_free_ Route *route = NULL;

Link *link = userdata;

usec_t time_now;

int r;

assert(nd);

assert(link);

if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))

return;

r = route_new(&route);

if (r < 0) {

log_link_error_errno(link, r, "Could not allocate route: %m");

return;

}

assert_se(sd_event_now(link->manager->event, clock_boottime_or_monotonic(), &time_now) >= 0);

route->family = AF_INET6;

route->table = RT_TABLE_MAIN;

route->protocol = RTPROT_RA;

route->flags = RTM_F_PREFIX;

route->dst.in6 = *prefix;

route->dst_prefixlen = prefixlen;

route->lifetime = time_now + lifetime * USEC_PER_SEC;

r = route_configure(route, link, ndisc_netlink_handler);

if (r < 0) {

log_link_warning_errno(link, r, "Could not set prefix route: %m");

link_enter_failed(link);

return;

}

link->ndisc_messages ++;

}

static void ndisc_router_handler(sd_ndisc *nd, uint8_t flags, const struct in6_addr *gateway, unsigned lifetime, int pref, void *userdata) {

_cleanup_route_free_ Route *route = NULL;

Link *link = userdata;

usec_t time_now;

int r;

assert(link);

assert(link->network);

assert(link->manager);

if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))

return;

if (flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)) {

if (flags & ND_RA_FLAG_MANAGED)

dhcp6_request_address(link);

r = sd_dhcp6_client_start(link->dhcp6_client);

if (r < 0 && r != -EBUSY)

log_link_warning_errno(link, r, "Starting DHCPv6 client on NDisc request failed: %m");

}

if (!gateway)

return;

r = route_new(&route);

if (r < 0) {

log_link_error_errno(link, r, "Could not allocate route: %m");

return;

}

assert_se(sd_event_now(link->manager->event, clock_boottime_or_monotonic(), &time_now) >= 0);

route->family = AF_INET6;

route->table = RT_TABLE_MAIN;

route->protocol = RTPROT_RA;

route->pref = pref;

route->gw.in6 = *gateway;

route->lifetime = time_now + lifetime * USEC_PER_SEC;

r = route_configure(route, link, ndisc_netlink_handler);

if (r < 0) {

log_link_warning_errno(link, r, "Could not set default route: %m");

link_enter_failed(link);

return;

}

link->ndisc_messages ++;

}

static void ndisc_handler(sd_ndisc *nd, int event, void *userdata) {

Link *link = userdata;

int r;

assert(link);

if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))

return;

switch (event) {

case SD_NDISC_EVENT_TIMEOUT:

dhcp6_request_address(link);

r = sd_dhcp6_client_start(link->dhcp6_client);

if (r < 0 && r != -EBUSY)

log_link_warning_errno(link, r, "Starting DHCPv6 client after NDisc timeout failed: %m");

break;

case SD_NDISC_EVENT_STOP:

break;

default:

log_link_warning(link, "IPv6 Neighbor Discovery unknown event: %d", event);

}

}

int ndisc_configure(Link *link) {

int r;

assert_return(link, -EINVAL);

r = sd_ndisc_new(&link->ndisc_router_discovery);

if (r < 0)

return r;

r = sd_ndisc_attach_event(link->ndisc_router_discovery, NULL, 0);

if (r < 0)

return r;

r = sd_ndisc_set_mac(link->ndisc_router_discovery, &link->mac);

if (r < 0)

return r;

r = sd_ndisc_set_index(link->ndisc_router_discovery, link->ifindex);

if (r < 0)

return r;

r = sd_ndisc_set_callback(link->ndisc_router_discovery,

ndisc_router_handler,

ndisc_prefix_onlink_handler,

ndisc_prefix_autonomous_handler,

ndisc_handler,

link);

return r;

}