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rtadv.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/* Router advertisement
* Copyright (C) 2016 Cumulus Networks
* Copyright (C) 2005 6WIND <jean-mickael.guerin@6wind.com>
* Copyright (C) 1999 Kunihiro Ishiguro
*/
#include <zebra.h>
#include "memory.h"
#include "sockopt.h"
#include "frrevent.h"
#include "if.h"
#include "stream.h"
#include "log.h"
#include "prefix.h"
#include "linklist.h"
#include "command.h"
#include "privs.h"
#include "vrf.h"
#include "ns.h"
#include "lib_errors.h"
#include "zebra/interface.h"
#include "zebra/rtadv.h"
#include "zebra/debug.h"
#include "zebra/rib.h"
#include "zebra/zapi_msg.h"
#include "zebra/zebra_vrf.h"
#include "zebra/zebra_errors.h"
#include "zebra/zebra_router.h"
extern struct zebra_privs_t zserv_privs;
static uint32_t interfaces_configured_for_ra_from_bgp;
#if defined(HAVE_RTADV)
#include "zebra/rtadv_clippy.c"
DEFINE_MTYPE_STATIC(ZEBRA, RTADV_PREFIX, "Router Advertisement Prefix");
DEFINE_MTYPE_STATIC(ZEBRA, ADV_IF, "Advertised Interface");
#ifdef OPEN_BSD
#include <netinet/icmp6.h>
#endif
/* If RFC2133 definition is used. */
#ifndef IPV6_JOIN_GROUP
#define IPV6_JOIN_GROUP IPV6_ADD_MEMBERSHIP
#endif
#ifndef IPV6_LEAVE_GROUP
#define IPV6_LEAVE_GROUP IPV6_DROP_MEMBERSHIP
#endif
#define ALLNODE "ff02::1"
#define ALLROUTER "ff02::2"
/* adv list node */
struct adv_if {
char name[INTERFACE_NAMSIZ];
struct adv_if_list_item list_item;
};
static int adv_if_cmp(const struct adv_if *a, const struct adv_if *b)
{
return if_cmp_name_func(a->name, b->name);
}
DECLARE_SORTLIST_UNIQ(adv_if_list, struct adv_if, list_item, adv_if_cmp);
static int rtadv_prefix_cmp(const struct rtadv_prefix *a,
const struct rtadv_prefix *b)
{
return prefix_cmp(&a->prefix, &b->prefix);
}
DECLARE_RBTREE_UNIQ(rtadv_prefixes, struct rtadv_prefix, item,
rtadv_prefix_cmp);
DEFINE_MTYPE_STATIC(ZEBRA, RTADV_RDNSS, "Router Advertisement RDNSS");
DEFINE_MTYPE_STATIC(ZEBRA, RTADV_DNSSL, "Router Advertisement DNSSL");
/* Order is intentional. Matches RFC4191. This array is also used for
command matching, so only modify with care. */
static const char *const rtadv_pref_strs[] = {
"medium", "high", "INVALID", "low", 0
};
enum rtadv_event {
RTADV_START,
RTADV_STOP,
RTADV_TIMER,
RTADV_TIMER_MSEC,
RTADV_READ
};
static void rtadv_event(struct zebra_vrf *, enum rtadv_event, int);
static int if_join_all_router(int, struct interface *);
static int if_leave_all_router(int, struct interface *);
static struct zebra_vrf *rtadv_interface_get_zvrf(const struct interface *ifp)
{
/* We use the default vrf for rtadv handling except in netns */
if (!vrf_is_backend_netns())
return vrf_info_lookup(VRF_DEFAULT);
return ifp->vrf->info;
}
static int rtadv_increment_received(struct zebra_vrf *zvrf, ifindex_t *ifindex)
{
int ret = -1;
struct interface *iface;
struct zebra_if *zif;
iface = if_lookup_by_index(*ifindex, zvrf->vrf->vrf_id);
if (iface && iface->info) {
zif = iface->info;
zif->ra_rcvd++;
ret = 0;
}
return ret;
}
static int rtadv_recv_packet(struct zebra_vrf *zvrf, int sock, uint8_t *buf,
int buflen, struct sockaddr_in6 *from,
ifindex_t *ifindex, int *hoplimit)
{
int ret;
struct msghdr msg;
struct iovec iov;
struct cmsghdr *cmsgptr;
struct in6_addr dst;
char adata[1024];
/* Fill in message and iovec. */
memset(&msg, 0, sizeof(msg));
msg.msg_name = (void *)from;
msg.msg_namelen = sizeof(struct sockaddr_in6);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = (void *)adata;
msg.msg_controllen = sizeof(adata);
iov.iov_base = buf;
iov.iov_len = buflen;
/* If recvmsg fail return minus value. */
ret = recvmsg(sock, &msg, 0);
if (ret < 0)
return ret;
for (cmsgptr = CMSG_FIRSTHDR(&msg); cmsgptr != NULL;
cmsgptr = CMSG_NXTHDR(&msg, cmsgptr)) {
/* I want interface index which this packet comes from. */
if (cmsgptr->cmsg_level == IPPROTO_IPV6
&& cmsgptr->cmsg_type == IPV6_PKTINFO) {
struct in6_pktinfo *ptr;
ptr = (struct in6_pktinfo *)CMSG_DATA(cmsgptr);
*ifindex = ptr->ipi6_ifindex;
memcpy(&dst, &ptr->ipi6_addr, sizeof(ptr->ipi6_addr));
}
/* Incoming packet's hop limit. */
if (cmsgptr->cmsg_level == IPPROTO_IPV6
&& cmsgptr->cmsg_type == IPV6_HOPLIMIT) {
int *hoptr = (int *)CMSG_DATA(cmsgptr);
*hoplimit = *hoptr;
}
}
rtadv_increment_received(zvrf, ifindex);
return ret;
}
#define RTADV_MSG_SIZE 4096
/* Send router advertisement packet. */
static void rtadv_send_packet(int sock, struct interface *ifp,
enum ipv6_nd_suppress_ra_status stop)
{
struct msghdr msg;
struct iovec iov;
struct cmsghdr *cmsgptr;
struct in6_pktinfo *pkt;
struct sockaddr_in6 addr;
static void *adata = NULL;
unsigned char buf[RTADV_MSG_SIZE];
struct nd_router_advert *rtadv;
int ret;
int len = 0;
struct zebra_if *zif;
struct rtadv_prefix *rprefix;
uint8_t all_nodes_addr[] = {0xff, 0x02, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 1};
struct listnode *node;
uint16_t pkt_RouterLifetime;
/*
* Allocate control message bufffer. This is dynamic because
* CMSG_SPACE is not guaranteed not to call a function. Note that
* the size will be different on different architectures due to
* differing alignment rules.
*/
if (adata == NULL) {
/* XXX Free on shutdown. */
adata = calloc(1, CMSG_SPACE(sizeof(struct in6_pktinfo)));
if (adata == NULL) {
zlog_debug("%s: can't malloc control data", __func__);
exit(-1);
}
}
/* Logging of packet. */
if (IS_ZEBRA_DEBUG_PACKET)
zlog_debug("%s(%s:%u): Tx RA, socket %u", ifp->name,
ifp->vrf->name, ifp->ifindex, sock);
/* Fill in sockaddr_in6. */
memset(&addr, 0, sizeof(struct sockaddr_in6));
addr.sin6_family = AF_INET6;
#ifdef SIN6_LEN
addr.sin6_len = sizeof(struct sockaddr_in6);
#endif /* SIN6_LEN */
addr.sin6_port = htons(IPPROTO_ICMPV6);
IPV6_ADDR_COPY(&addr.sin6_addr, all_nodes_addr);
/* Fetch interface information. */
zif = ifp->info;
/* Make router advertisement message. */
rtadv = (struct nd_router_advert *)buf;
rtadv->nd_ra_type = ND_ROUTER_ADVERT;
rtadv->nd_ra_code = 0;
rtadv->nd_ra_cksum = 0;
rtadv->nd_ra_curhoplimit = zif->rtadv.AdvCurHopLimit;
/* RFC4191: Default Router Preference is 0 if Router Lifetime is 0. */
rtadv->nd_ra_flags_reserved = zif->rtadv.AdvDefaultLifetime == 0
? 0
: zif->rtadv.DefaultPreference;
rtadv->nd_ra_flags_reserved <<= 3;
if (zif->rtadv.AdvManagedFlag)
rtadv->nd_ra_flags_reserved |= ND_RA_FLAG_MANAGED;
if (zif->rtadv.AdvOtherConfigFlag)
rtadv->nd_ra_flags_reserved |= ND_RA_FLAG_OTHER;
if (zif->rtadv.AdvHomeAgentFlag)
rtadv->nd_ra_flags_reserved |= ND_RA_FLAG_HOME_AGENT;
/* Note that according to Neighbor Discovery (RFC 4861 [18]),
* AdvDefaultLifetime is by default based on the value of
* MaxRtrAdvInterval. AdvDefaultLifetime is used in the Router Lifetime
* field of Router Advertisements. Given that this field is expressed
* in seconds, a small MaxRtrAdvInterval value can result in a zero
* value for this field. To prevent this, routers SHOULD keep
* AdvDefaultLifetime in at least one second, even if the use of
* MaxRtrAdvInterval would result in a smaller value. -- RFC6275, 7.5 */
pkt_RouterLifetime =
zif->rtadv.AdvDefaultLifetime != -1
? zif->rtadv.AdvDefaultLifetime
: MAX(1, 0.003 * zif->rtadv.MaxRtrAdvInterval);
/* send RA lifetime of 0 before stopping. rfc4861/6.2.5 */
rtadv->nd_ra_router_lifetime =
(stop == RA_SUPPRESS) ? htons(0) : htons(pkt_RouterLifetime);
rtadv->nd_ra_reachable = htonl(zif->rtadv.AdvReachableTime);
rtadv->nd_ra_retransmit = htonl(zif->rtadv.AdvRetransTimer);
len = sizeof(struct nd_router_advert);
/* If both the Home Agent Preference and Home Agent Lifetime are set to
* their default values specified above, this option SHOULD NOT be
* included in the Router Advertisement messages sent by this home
* agent. -- RFC6275, 7.4 */
if (zif->rtadv.AdvHomeAgentFlag
&& (zif->rtadv.HomeAgentPreference
|| zif->rtadv.HomeAgentLifetime != -1)) {
struct nd_opt_homeagent_info *ndopt_hai =
(struct nd_opt_homeagent_info *)(buf + len);
ndopt_hai->nd_opt_hai_type = ND_OPT_HA_INFORMATION;
ndopt_hai->nd_opt_hai_len = 1;
ndopt_hai->nd_opt_hai_reserved = 0;
ndopt_hai->nd_opt_hai_preference =
htons(zif->rtadv.HomeAgentPreference);
/* 16-bit unsigned integer. The lifetime associated with the
* home
* agent in units of seconds. The default value is the same as
* the
* Router Lifetime, as specified in the main body of the Router
* Advertisement. The maximum value corresponds to 18.2 hours.
* A
* value of 0 MUST NOT be used. -- RFC6275, 7.5 */
ndopt_hai->nd_opt_hai_lifetime =
htons(zif->rtadv.HomeAgentLifetime != -1
? zif->rtadv.HomeAgentLifetime
: MAX(1, pkt_RouterLifetime) /* 0 is OK
for RL,
but not
for HAL*/
);
len += sizeof(struct nd_opt_homeagent_info);
}
if (zif->rtadv.AdvIntervalOption) {
struct nd_opt_adv_interval *ndopt_adv =
(struct nd_opt_adv_interval *)(buf + len);
ndopt_adv->nd_opt_ai_type = ND_OPT_ADV_INTERVAL;
ndopt_adv->nd_opt_ai_len = 1;
ndopt_adv->nd_opt_ai_reserved = 0;
ndopt_adv->nd_opt_ai_interval =
htonl(zif->rtadv.MaxRtrAdvInterval);
len += sizeof(struct nd_opt_adv_interval);
}
/* Fill in prefix. */
frr_each (rtadv_prefixes, zif->rtadv.prefixes, rprefix) {
struct nd_opt_prefix_info *pinfo;
pinfo = (struct nd_opt_prefix_info *)(buf + len);
pinfo->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
pinfo->nd_opt_pi_len = 4;
pinfo->nd_opt_pi_prefix_len = rprefix->prefix.prefixlen;
pinfo->nd_opt_pi_flags_reserved = 0;
if (rprefix->AdvOnLinkFlag)
pinfo->nd_opt_pi_flags_reserved |=
ND_OPT_PI_FLAG_ONLINK;
if (rprefix->AdvAutonomousFlag)
pinfo->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO;
if (rprefix->AdvRouterAddressFlag)
pinfo->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_RADDR;
pinfo->nd_opt_pi_valid_time = htonl(rprefix->AdvValidLifetime);
pinfo->nd_opt_pi_preferred_time =
htonl(rprefix->AdvPreferredLifetime);
pinfo->nd_opt_pi_reserved2 = 0;
IPV6_ADDR_COPY(&pinfo->nd_opt_pi_prefix,
&rprefix->prefix.prefix);
len += sizeof(struct nd_opt_prefix_info);
}
/* Hardware address. */
if (ifp->hw_addr_len != 0) {
buf[len++] = ND_OPT_SOURCE_LINKADDR;
/* Option length should be rounded up to next octet if
the link address does not end on an octet boundary. */
buf[len++] = (ifp->hw_addr_len + 9) >> 3;
memcpy(buf + len, ifp->hw_addr, ifp->hw_addr_len);
len += ifp->hw_addr_len;
/* Pad option to end on an octet boundary. */
memset(buf + len, 0, -(ifp->hw_addr_len + 2) & 0x7);
len += -(ifp->hw_addr_len + 2) & 0x7;
}
/* MTU */
if (zif->rtadv.AdvLinkMTU) {
struct nd_opt_mtu *opt = (struct nd_opt_mtu *)(buf + len);
opt->nd_opt_mtu_type = ND_OPT_MTU;
opt->nd_opt_mtu_len = 1;
opt->nd_opt_mtu_reserved = 0;
opt->nd_opt_mtu_mtu = htonl(zif->rtadv.AdvLinkMTU);
len += sizeof(struct nd_opt_mtu);
}
/*
* There is no limit on the number of configurable recursive DNS
* servers or search list entries. We don't want the RA message
* to exceed the link's MTU (risking fragmentation) or even
* blow the stack buffer allocated for it.
*/
size_t max_len = MIN(ifp->mtu6 - 40, sizeof(buf));
/* Recursive DNS servers */
struct rtadv_rdnss *rdnss;
for (ALL_LIST_ELEMENTS_RO(zif->rtadv.AdvRDNSSList, node, rdnss)) {
size_t opt_len =
sizeof(struct nd_opt_rdnss) + sizeof(struct in6_addr);
if (len + opt_len > max_len) {
zlog_warn(
"%s(%s:%u): Tx RA: RDNSS option would exceed MTU, omitting it",
ifp->name, ifp->vrf->name, ifp->ifindex);
goto no_more_opts;
}
struct nd_opt_rdnss *opt = (struct nd_opt_rdnss *)(buf + len);
opt->nd_opt_rdnss_type = ND_OPT_RDNSS;
opt->nd_opt_rdnss_len = opt_len / 8;
opt->nd_opt_rdnss_reserved = 0;
opt->nd_opt_rdnss_lifetime = htonl(
rdnss->lifetime_set
? rdnss->lifetime
: MAX(1, 0.003 * zif->rtadv.MaxRtrAdvInterval));
len += sizeof(struct nd_opt_rdnss);
IPV6_ADDR_COPY(buf + len, &rdnss->addr);
len += sizeof(struct in6_addr);
}
/* DNS search list */
struct rtadv_dnssl *dnssl;
for (ALL_LIST_ELEMENTS_RO(zif->rtadv.AdvDNSSLList, node, dnssl)) {
size_t opt_len = sizeof(struct nd_opt_dnssl)
+ ((dnssl->encoded_len + 7) & ~7);
if (len + opt_len > max_len) {
zlog_warn(
"%s(%u): Tx RA: DNSSL option would exceed MTU, omitting it",
ifp->name, ifp->ifindex);
goto no_more_opts;
}
struct nd_opt_dnssl *opt = (struct nd_opt_dnssl *)(buf + len);
opt->nd_opt_dnssl_type = ND_OPT_DNSSL;
opt->nd_opt_dnssl_len = opt_len / 8;
opt->nd_opt_dnssl_reserved = 0;
opt->nd_opt_dnssl_lifetime = htonl(
dnssl->lifetime_set
? dnssl->lifetime
: MAX(1, 0.003 * zif->rtadv.MaxRtrAdvInterval));
len += sizeof(struct nd_opt_dnssl);
memcpy(buf + len, dnssl->encoded_name, dnssl->encoded_len);
len += dnssl->encoded_len;
/* Zero-pad to 8-octet boundary */
while (len % 8)
buf[len++] = '\0';
}
no_more_opts:
msg.msg_name = (void *)&addr;
msg.msg_namelen = sizeof(struct sockaddr_in6);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = (void *)adata;
msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
msg.msg_flags = 0;
iov.iov_base = buf;
iov.iov_len = len;
cmsgptr = CMSG_FIRSTHDR(&msg);
cmsgptr->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
cmsgptr->cmsg_level = IPPROTO_IPV6;
cmsgptr->cmsg_type = IPV6_PKTINFO;
pkt = (struct in6_pktinfo *)CMSG_DATA(cmsgptr);
memset(&pkt->ipi6_addr, 0, sizeof(struct in6_addr));
pkt->ipi6_ifindex = ifp->ifindex;
ret = sendmsg(sock, &msg, 0);
if (ret < 0) {
flog_err_sys(EC_LIB_SOCKET,
"%s(%u): Tx RA failed, socket %u error %d (%s)",
ifp->name, ifp->ifindex, sock, errno,
safe_strerror(errno));
} else
zif->ra_sent++;
}
static void rtadv_timer(struct event *thread)
{
struct zebra_vrf *zvrf = EVENT_ARG(thread);
struct vrf *vrf;
struct interface *ifp;
struct zebra_if *zif;
int period;
zvrf->rtadv.ra_timer = NULL;
if (adv_if_list_count(&zvrf->rtadv.adv_msec_if) == 0) {
period = 1000; /* 1 s */
rtadv_event(zvrf, RTADV_TIMER, 1 /* 1 s */);
} else {
period = 10; /* 10 ms */
rtadv_event(zvrf, RTADV_TIMER_MSEC, 10 /* 10 ms */);
}
RB_FOREACH (vrf, vrf_id_head, &vrfs_by_id)
FOR_ALL_INTERFACES (vrf, ifp) {
if (if_is_loopback(ifp) || !if_is_operative(ifp) ||
IS_ZEBRA_IF_BRIDGE_SLAVE(ifp) ||
!connected_get_linklocal(ifp) ||
(vrf_is_backend_netns() &&
ifp->vrf->vrf_id != zvrf->vrf->vrf_id))
continue;
zif = ifp->info;
if (zif->rtadv.AdvSendAdvertisements) {
if (zif->rtadv.inFastRexmit
&& zif->rtadv.UseFastRexmit) {
/* We assume we fast rexmit every sec so
* no
* additional vars */
if (--zif->rtadv.NumFastReXmitsRemain
<= 0)
zif->rtadv.inFastRexmit = 0;
if (IS_ZEBRA_DEBUG_SEND)
zlog_debug(
"Fast RA Rexmit on interface %s(%s:%u)",
ifp->name,
ifp->vrf->name,
ifp->ifindex);
rtadv_send_packet(zvrf->rtadv.sock, ifp,
RA_ENABLE);
} else {
zif->rtadv.AdvIntervalTimer -= period;
if (zif->rtadv.AdvIntervalTimer <= 0) {
/* FIXME: using
MaxRtrAdvInterval each
time isn't what section
6.2.4 of RFC4861 tells to do.
*/
zif->rtadv.AdvIntervalTimer =
zif->rtadv
.MaxRtrAdvInterval;
rtadv_send_packet(
zvrf->rtadv.sock, ifp,
RA_ENABLE);
}
}
}
}
}
static void rtadv_process_solicit(struct interface *ifp)
{
struct zebra_vrf *zvrf;
struct zebra_if *zif;
zvrf = rtadv_interface_get_zvrf(ifp);
assert(zvrf);
zif = ifp->info;
/*
* If FastRetransmit is enabled, send the RA immediately.
* If not enabled but it has been more than MIN_DELAY_BETWEEN_RAS
* (3 seconds) since the last RA was sent, send it now and reset
* the timer to start at the max (configured) again.
* If not enabled and it is less than 3 seconds since the last
* RA packet was sent, set the timer for 3 seconds so the next
* one will be sent with a minimum of 3 seconds between RAs.
* RFC4861 sec 6.2.6
*/
if ((zif->rtadv.UseFastRexmit)
|| (zif->rtadv.AdvIntervalTimer <=
(zif->rtadv.MaxRtrAdvInterval - MIN_DELAY_BETWEEN_RAS))) {
rtadv_send_packet(zvrf->rtadv.sock, ifp, RA_ENABLE);
zif->rtadv.AdvIntervalTimer = zif->rtadv.MaxRtrAdvInterval;
} else
zif->rtadv.AdvIntervalTimer = MIN_DELAY_BETWEEN_RAS;
}
static const char *rtadv_optionalhdr2str(uint8_t opt_type)
{
switch (opt_type) {
case ND_OPT_SOURCE_LINKADDR:
return "Optional Source Link Address";
case ND_OPT_TARGET_LINKADDR:
return "Optional Target Link Address";
case ND_OPT_PREFIX_INFORMATION:
return "Optional Prefix Information";
case ND_OPT_REDIRECTED_HEADER:
return "Optional Redirected Header";
case ND_OPT_MTU:
return "Optional MTU";
case ND_OPT_RTR_ADV_INTERVAL:
return "Optional Advertisement Interval";
case ND_OPT_HOME_AGENT_INFO:
return "Optional Home Agent Information";
}
return "Unknown Optional Type";
}
/*
* This function processes optional attributes off of
* end of a RA packet received. At this point in
* time we only care about this in one situation
* which is when a interface does not have a LL
* v6 address. We still need to be able to install
* the mac address for v4 to v6 resolution
*/
static void rtadv_process_optional(uint8_t *optional, unsigned int len,
struct interface *ifp,
struct sockaddr_in6 *addr)
{
char *mac;
while (len > 0) {
struct nd_opt_hdr *opt_hdr = (struct nd_opt_hdr *)optional;
switch(opt_hdr->nd_opt_type) {
case ND_OPT_SOURCE_LINKADDR:
mac = (char *)(optional+2);
if_nbr_mac_to_ipv4ll_neigh_update(ifp, mac,
&addr->sin6_addr, 1);
break;
default:
if (IS_ZEBRA_DEBUG_PACKET)
zlog_debug(
"%s:Received Packet with optional Header type %s(%u) that is being ignored",
__func__,
rtadv_optionalhdr2str(
opt_hdr->nd_opt_type),
opt_hdr->nd_opt_type);
break;
}
len -= 8 * opt_hdr->nd_opt_len;
optional += 8 * opt_hdr->nd_opt_len;
}
}
static void rtadv_process_advert(uint8_t *msg, unsigned int len,
struct interface *ifp,
struct sockaddr_in6 *addr)
{
struct nd_router_advert *radvert;
char addr_str[INET6_ADDRSTRLEN];
struct zebra_if *zif;
struct prefix p;
zif = ifp->info;
inet_ntop(AF_INET6, &addr->sin6_addr, addr_str, INET6_ADDRSTRLEN);
if (len < sizeof(struct nd_router_advert)) {
if (IS_ZEBRA_DEBUG_PACKET)
zlog_debug(
"%s(%s:%u): Rx RA with invalid length %d from %s",
ifp->name, ifp->vrf->name, ifp->ifindex, len,
addr_str);
return;
}
if (!IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
rtadv_process_optional(msg + sizeof(struct nd_router_advert),
len - sizeof(struct nd_router_advert),
ifp, addr);
if (IS_ZEBRA_DEBUG_PACKET)
zlog_debug(
"%s(%s:%u): Rx RA with non-linklocal source address from %s",
ifp->name, ifp->vrf->name, ifp->ifindex,
addr_str);
return;
}
radvert = (struct nd_router_advert *)msg;
#define SIXHOUR2USEC (int64_t)6 * 60 * 60 * 1000000
if ((radvert->nd_ra_curhoplimit && zif->rtadv.AdvCurHopLimit) &&
(radvert->nd_ra_curhoplimit != zif->rtadv.AdvCurHopLimit) &&
(monotime_since(&zif->rtadv.lastadvcurhoplimit, NULL) >
SIXHOUR2USEC ||
zif->rtadv.lastadvcurhoplimit.tv_sec == 0)) {
flog_warn(
EC_ZEBRA_RA_PARAM_MISMATCH,
"%s(%u): Rx RA - our AdvCurHopLimit (%u) doesn't agree with %s (%u)",
ifp->name, ifp->ifindex, zif->rtadv.AdvCurHopLimit,
addr_str, radvert->nd_ra_curhoplimit);
monotime(&zif->rtadv.lastadvcurhoplimit);
}
if ((radvert->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) &&
!zif->rtadv.AdvManagedFlag &&
(monotime_since(&zif->rtadv.lastadvmanagedflag, NULL) >
SIXHOUR2USEC ||
zif->rtadv.lastadvmanagedflag.tv_sec == 0)) {
flog_warn(
EC_ZEBRA_RA_PARAM_MISMATCH,
"%s(%u): Rx RA - our AdvManagedFlag (%u) doesn't agree with %s (%u)",
ifp->name, ifp->ifindex, zif->rtadv.AdvManagedFlag,
addr_str,
!!CHECK_FLAG(radvert->nd_ra_flags_reserved,
ND_RA_FLAG_MANAGED));
monotime(&zif->rtadv.lastadvmanagedflag);
}
if ((radvert->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) &&
!zif->rtadv.AdvOtherConfigFlag &&
(monotime_since(&zif->rtadv.lastadvotherconfigflag, NULL) >
SIXHOUR2USEC ||
zif->rtadv.lastadvotherconfigflag.tv_sec == 0)) {
flog_warn(
EC_ZEBRA_RA_PARAM_MISMATCH,
"%s(%u): Rx RA - our AdvOtherConfigFlag (%u) doesn't agree with %s (%u)",
ifp->name, ifp->ifindex, zif->rtadv.AdvOtherConfigFlag,
addr_str,
!!CHECK_FLAG(radvert->nd_ra_flags_reserved,
ND_RA_FLAG_OTHER));
monotime(&zif->rtadv.lastadvotherconfigflag);
}
if ((radvert->nd_ra_reachable && zif->rtadv.AdvReachableTime) &&
(ntohl(radvert->nd_ra_reachable) != zif->rtadv.AdvReachableTime) &&
(monotime_since(&zif->rtadv.lastadvreachabletime, NULL) >
SIXHOUR2USEC ||
zif->rtadv.lastadvreachabletime.tv_sec == 0)) {
flog_warn(
EC_ZEBRA_RA_PARAM_MISMATCH,
"%s(%u): Rx RA - our AdvReachableTime (%u) doesn't agree with %s (%u)",
ifp->name, ifp->ifindex, zif->rtadv.AdvReachableTime,
addr_str, ntohl(radvert->nd_ra_reachable));
monotime(&zif->rtadv.lastadvreachabletime);
}
if ((radvert->nd_ra_retransmit && zif->rtadv.AdvRetransTimer) &&
(ntohl(radvert->nd_ra_retransmit) !=
(unsigned int)zif->rtadv.AdvRetransTimer) &&
(monotime_since(&zif->rtadv.lastadvretranstimer, NULL) >
SIXHOUR2USEC ||
zif->rtadv.lastadvretranstimer.tv_sec == 0)) {
flog_warn(
EC_ZEBRA_RA_PARAM_MISMATCH,
"%s(%u): Rx RA - our AdvRetransTimer (%u) doesn't agree with %s (%u)",
ifp->name, ifp->ifindex, zif->rtadv.AdvRetransTimer,
addr_str, ntohl(radvert->nd_ra_retransmit));
monotime(&zif->rtadv.lastadvretranstimer);
}
/* Create entry for neighbor if not known. */
p.family = AF_INET6;
IPV6_ADDR_COPY(&p.u.prefix6, &addr->sin6_addr);
p.prefixlen = IPV6_MAX_BITLEN;
if (!nbr_connected_check(ifp, &p))
nbr_connected_add_ipv6(ifp, &addr->sin6_addr);
}
static void rtadv_process_packet(uint8_t *buf, unsigned int len,
ifindex_t ifindex, int hoplimit,
struct sockaddr_in6 *from,
struct zebra_vrf *zvrf)
{
struct icmp6_hdr *icmph;
struct interface *ifp;
struct zebra_if *zif;
char addr_str[INET6_ADDRSTRLEN];
inet_ntop(AF_INET6, &from->sin6_addr, addr_str, INET6_ADDRSTRLEN);
/* Interface search. */
ifp = if_lookup_by_index(ifindex, zvrf->vrf->vrf_id);
if (ifp == NULL) {
flog_warn(EC_ZEBRA_UNKNOWN_INTERFACE,
"RA/RS received on unknown IF %u from %s", ifindex,
addr_str);
return;
}
if (IS_ZEBRA_DEBUG_PACKET)
zlog_debug("%s(%s:%u): Rx RA/RS len %d from %s", ifp->name,
ifp->vrf->name, ifp->ifindex, len, addr_str);
if (if_is_loopback(ifp))
return;
/* Check interface configuration. */
zif = ifp->info;
if (!zif->rtadv.AdvSendAdvertisements)
return;
/* ICMP message length check. */
if (len < sizeof(struct icmp6_hdr)) {
zlog_debug(
"%s(%s:%u): Rx RA with Invalid ICMPV6 packet length %d",
ifp->name, ifp->vrf->name, ifp->ifindex, len);
return;
}
icmph = (struct icmp6_hdr *)buf;
/* ICMP message type check. */
if (icmph->icmp6_type != ND_ROUTER_SOLICIT
&& icmph->icmp6_type != ND_ROUTER_ADVERT) {
zlog_debug("%s(%s:%u): Rx RA - Unwanted ICMPV6 message type %d",
ifp->name, ifp->vrf->name, ifp->ifindex,
icmph->icmp6_type);
return;
}
/* Hoplimit check. */
if (hoplimit >= 0 && hoplimit != 255) {
zlog_debug("%s(%s:%u): Rx RA - Invalid hoplimit %d", ifp->name,
ifp->vrf->name, ifp->ifindex, hoplimit);
return;
}
/* Check ICMP message type. */
if (icmph->icmp6_type == ND_ROUTER_SOLICIT)
rtadv_process_solicit(ifp);
else if (icmph->icmp6_type == ND_ROUTER_ADVERT)
rtadv_process_advert(buf, len, ifp, from);
return;
}
static void rtadv_read(struct event *thread)
{
int sock;
int len;
uint8_t buf[RTADV_MSG_SIZE];
struct sockaddr_in6 from;
ifindex_t ifindex = 0;
int hoplimit = -1;
struct zebra_vrf *zvrf = EVENT_ARG(thread);
sock = EVENT_FD(thread);
zvrf->rtadv.ra_read = NULL;
/* Register myself. */
rtadv_event(zvrf, RTADV_READ, 0);
len = rtadv_recv_packet(zvrf, sock, buf, sizeof(buf), &from, &ifindex,
&hoplimit);
if (len < 0) {
flog_err_sys(EC_LIB_SOCKET,
"RA/RS recv failed, socket %u error %s", sock,
safe_strerror(errno));
return;
}
rtadv_process_packet(buf, (unsigned)len, ifindex, hoplimit, &from, zvrf);
}
static int rtadv_make_socket(ns_id_t ns_id)
{
int sock = -1;
int ret = 0;
struct icmp6_filter filter;
int error;
frr_with_privs(&zserv_privs) {
sock = ns_socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6, ns_id);
/*
* with privs might set errno too if it fails save
* to the side
*/
error = errno;
}
if (sock < 0) {
zlog_warn("RTADV socket for ns: %u failure to create: %s(%u)",
ns_id, safe_strerror(error), error);
return -1;
}
ret = setsockopt_ipv6_pktinfo(sock, 1);
if (ret < 0) {
zlog_warn("RTADV failure to set Packet Information");
close(sock);
return ret;
}
ret = setsockopt_ipv6_multicast_loop(sock, 0);
if (ret < 0) {
zlog_warn("RTADV failure to set multicast Loop detection");
close(sock);
return ret;
}
ret = setsockopt_ipv6_unicast_hops(sock, 255);
if (ret < 0) {
zlog_warn("RTADV failure to set maximum unicast hops");
close(sock);
return ret;
}
ret = setsockopt_ipv6_multicast_hops(sock, 255);
if (ret < 0) {
zlog_warn("RTADV failure to set maximum multicast hops");
close(sock);
return ret;
}
ret = setsockopt_ipv6_hoplimit(sock, 1);
if (ret < 0) {
zlog_warn("RTADV failure to set maximum incoming hop limit");
close(sock);
return ret;
}
ICMP6_FILTER_SETBLOCKALL(&filter);
ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filter);
ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filter);
ret = setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filter,
sizeof(struct icmp6_filter));
if (ret < 0) {
zlog_info("ICMP6_FILTER set fail: %s", safe_strerror(errno));
close(sock);
return ret;
}
return sock;
}
static struct adv_if *adv_if_new(const char *name)
{
struct adv_if *new;
new = XCALLOC(MTYPE_ADV_IF, sizeof(struct adv_if));
strlcpy(new->name, name, sizeof(new->name));
return new;
}
static void adv_if_free(struct adv_if *adv_if)
{
XFREE(MTYPE_ADV_IF, adv_if);
}
static bool adv_if_is_empty_internal(const struct adv_if_list_head *adv_if_head)
{
return adv_if_list_count(adv_if_head) ? false : true;
}
static struct adv_if *adv_if_add_internal(struct adv_if_list_head *adv_if_head,
const char *name)
{
struct adv_if adv_if_lookup = {};
struct adv_if *adv_if = NULL;
strlcpy(adv_if_lookup.name, name, sizeof(adv_if_lookup.name));
adv_if = adv_if_list_find(adv_if_head, &adv_if_lookup);
if (adv_if != NULL)
return adv_if;
adv_if = adv_if_new(adv_if_lookup.name);
adv_if_list_add(adv_if_head, adv_if);
return NULL;
}
static struct adv_if *adv_if_del_internal(struct adv_if_list_head *adv_if_head,
const char *name)
{
struct adv_if adv_if_lookup = {};
struct adv_if *adv_if = NULL;
strlcpy(adv_if_lookup.name, name, sizeof(adv_if_lookup.name));
adv_if = adv_if_list_find(adv_if_head, &adv_if_lookup);
if (adv_if == NULL)
return NULL;
adv_if_list_del(adv_if_head, adv_if);
return adv_if;
}
static void adv_if_clean_internal(struct adv_if_list_head *adv_if_head)
{
struct adv_if *node = NULL;
if (!adv_if_is_empty_internal(adv_if_head)) {
frr_each_safe (adv_if_list, adv_if_head, node) {
adv_if_list_del(adv_if_head, node);
adv_if_free(node);
}
}
adv_if_list_fini(adv_if_head);
}
/*
* Add to list. On Success, return NULL, otherwise return already existing
* adv_if.
*/
static struct adv_if *adv_if_add(struct zebra_vrf *zvrf, const char *name)
{
struct adv_if *adv_if = NULL;
adv_if = adv_if_add_internal(&zvrf->rtadv.adv_if, name);
if (adv_if != NULL)
return adv_if;