Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
5650392b38
NetBSD/usr.sbin/mrouted/vif.c
gdt 91f284e510 Fix bug in mrouted about aging neighbors. 
mrouted will periodically age its neighbors and will remove a neighbor
if it hasn't heard from it for NEIGHBOR_EXPIRE_TIME. Unfortunately, the
neighbor pointers 'a' and 'prev_a' were never advanced when timer was
not expired. Therefore it would get stuck in a tight loop, advancing
'al_timer' until it would be greater than NEIGHBOR_EXPIRE_TIME. This
caused the neighbor to allways get timed out and dropped. Furthermore,
there was a second bug in this loop when deleting an item that was not
at the head of the list (i.e., prev_a should stay the same instead of
advancing).

This bug fix is the work of Konrad Lorincz.  Bug found and fix made on
netbsd-6.

This material is based upon work supported by the Defense Advanced
Research Projects Agency and Space and Naval Warfare Systems Center,
Pacific, under Contract No. N66001-09-C-2073.  Any opinions, findings
and conclusions or recommendations expressed in this material are
those of the author(s) and do not necessarily reflect the views of the
Defense Advanced Research Project Agency and Space and Naval Warfare
Systems Center, Pacific.
Approved for Public Release, Distribution Unlimited
2015-02-05 16:50:19 +00:00

1457 lines
36 KiB
C
Raw Blame History

/* $NetBSD: vif.c,v 1.19 2015/02/05 16:50:19 gdt Exp $ */
/*
* The mrouted program is covered by the license in the accompanying file
* named "LICENSE". Use of the mrouted program represents acceptance of
* the terms and conditions listed in that file.
*
* The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
* Leland Stanford Junior University.
*/
#include "defs.h"
#include <fcntl.h>
/*
* Exported variables.
*/
struct uvif uvifs[MAXVIFS]; /* array of virtual interfaces */
vifi_t numvifs; /* number of vifs in use */
int vifs_down; /* 1=>some interfaces are down */
int phys_vif; /* An enabled vif */
int udp_socket; /* Since the honkin' kernel doesn't support */
/* ioctls on raw IP sockets, we need a UDP */
/* socket as well as our IGMP (raw) socket. */
/* How dumb. */
int vifs_with_neighbors; /* == 1 if I am a leaf */
typedef struct {
vifi_t vifi;
struct listaddr *g;
int q_time;
} cbk_t;
/*
* Forward declarations.
*/
static void start_vif(vifi_t vifi);
static void start_vif2(vifi_t vifi);
static void stop_vif(vifi_t vifi);
static void age_old_hosts(void);
static void send_probe_on_vif(struct uvif *v);
static int info_version(char *p, size_t);
static void DelVif(void *arg);
static int SetTimer(vifi_t vifi, struct listaddr *g);
static int DeleteTimer(int id);
static void SendQuery(void *arg);
static int SetQueryTimer(struct listaddr *g, vifi_t vifi, int to_expire,
int q_time);
/*
* Initialize the virtual interfaces, but do not install
* them in the kernel. Start routing on all vifs that are
* not down or disabled.
*/
void
init_vifs(void)
{
vifi_t vifi;
struct uvif *v;
int enabled_vifs, enabled_phyints;
extern char *configfilename;
numvifs = 0;
vifs_with_neighbors = 0;
vifs_down = FALSE;
/*
* Configure the vifs based on the interface configuration of the
* the kernel and the contents of the configuration file.
* (Open a UDP socket for ioctl use in the config procedures.)
*/
if ((udp_socket = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
logit(LOG_ERR, errno, "UDP socket");
logit(LOG_INFO,0,"Getting vifs from kernel interfaces");
config_vifs_from_kernel();
logit(LOG_INFO,0,"Getting vifs from %s",configfilename);
config_vifs_from_file();
/*
* Quit if there are fewer than two enabled vifs.
*/
enabled_vifs = 0;
enabled_phyints = 0;
phys_vif = -1;
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (!(v->uv_flags & VIFF_DISABLED)) {
++enabled_vifs;
if (!(v->uv_flags & VIFF_TUNNEL)) {
if (phys_vif == -1)
phys_vif = vifi;
++enabled_phyints;
}
}
}
if (enabled_vifs < 2)
logit(LOG_ERR, 0, "can't forward: %s",
enabled_vifs == 0 ? "no enabled vifs" : "only one enabled vif");
if (enabled_phyints == 0)
logit(LOG_WARNING, 0,
"no enabled interfaces, forwarding via tunnels only");
logit(LOG_INFO, 0, "Installing vifs in mrouted...");
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (!(v->uv_flags & VIFF_DISABLED)) {
if (!(v->uv_flags & VIFF_DOWN)) {
if (v->uv_flags & VIFF_TUNNEL)
logit(LOG_INFO, 0, "vif #%d, tunnel %s -> %s", vifi,
inet_fmt(v->uv_lcl_addr),
inet_fmt(v->uv_rmt_addr));
else
logit(LOG_INFO, 0, "vif #%d, phyint %s", vifi,
inet_fmt(v->uv_lcl_addr));
start_vif2(vifi);
} else logit(LOG_INFO, 0,
"%s is not yet up; vif #%u not in service",
v->uv_name, vifi);
}
}
}
/*
* Start routing on all virtual interfaces that are not down or
* administratively disabled.
*/
void
init_installvifs(void)
{
vifi_t vifi;
struct uvif *v;
logit(LOG_INFO, 0, "Installing vifs in kernel...");
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (!(v->uv_flags & VIFF_DISABLED)) {
if (!(v->uv_flags & VIFF_DOWN)) {
if (v->uv_flags & VIFF_TUNNEL)
logit(LOG_INFO, 0, "vif #%d, tunnel %s -> %s", vifi,
inet_fmt(v->uv_lcl_addr),
inet_fmt(v->uv_rmt_addr));
else
logit(LOG_INFO, 0, "vif #%d, phyint %s", vifi,
inet_fmt(v->uv_lcl_addr));
k_add_vif(vifi, &uvifs[vifi]);
} else logit(LOG_INFO, 0,
"%s is not yet up; vif #%u not in service",
v->uv_name, vifi);
}
}
}
/*
* See if any interfaces have changed from up state to down, or vice versa,
* including any non-multicast-capable interfaces that are in use as local
* tunnel end-points. Ignore interfaces that have been administratively
* disabled.
*/
void
check_vif_state(void)
{
vifi_t vifi;
struct uvif *v;
struct ifreq ifr;
vifs_down = FALSE;
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (v->uv_flags & VIFF_DISABLED) continue;
strncpy(ifr.ifr_name, v->uv_name, IFNAMSIZ);
if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ifr) < 0)
logit(LOG_ERR, errno,
"ioctl SIOCGIFFLAGS for %s", ifr.ifr_name);
if (v->uv_flags & VIFF_DOWN) {
if (ifr.ifr_flags & IFF_UP) {
v->uv_flags &= ~VIFF_DOWN;
start_vif(vifi);
logit(LOG_INFO, 0,
"%s has come up; vif #%u now in service",
v->uv_name, vifi);
}
else vifs_down = TRUE;
}
else {
if (!(ifr.ifr_flags & IFF_UP)) {
stop_vif(vifi);
v->uv_flags |= VIFF_DOWN;
logit(LOG_INFO, 0,
"%s has gone down; vif #%u taken out of service",
v->uv_name, vifi);
vifs_down = TRUE;
}
}
}
}
/*
* Send a probe message on vif v
*/
static void
send_probe_on_vif(struct uvif *v)
{
char *p;
int datalen = 0;
struct listaddr *nbr;
int i;
p = send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN;
for (i = 0; i < 4; i++)
*p++ = ((char *)&(dvmrp_genid))[i];
datalen += 4;
/*
* add the neighbor list on the interface to the message
*/
nbr = v->uv_neighbors;
while (nbr) {
for (i = 0; i < 4; i++)
*p++ = ((char *)&nbr->al_addr)[i];
datalen +=4;
nbr = nbr->al_next;
}
send_igmp(v->uv_lcl_addr,
(v->uv_flags & VIFF_TUNNEL) ? v->uv_rmt_addr
: dvmrp_group,
IGMP_DVMRP, DVMRP_PROBE,
htonl(MROUTED_LEVEL |
((v->uv_flags & VIFF_LEAF) ? 0 : LEAF_FLAGS)),
datalen);
}
/*
* Add a vifi to the kernel and start routing on it.
*/
static void
start_vif(vifi_t vifi)
{
/*
* Install the interface in the kernel's vif structure.
*/
k_add_vif(vifi, &uvifs[vifi]);
start_vif2(vifi);
}
/*
* Add a vifi to all the user-level data structures but don't add
* it to the kernel yet.
*/
static void
start_vif2(vifi_t vifi)
{
struct uvif *v;
u_int32_t src;
struct phaddr *p;
v = &uvifs[vifi];
src = v->uv_lcl_addr;
/*
* Update the existing route entries to take into account the new vif.
*/
add_vif_to_routes(vifi);
if (!(v->uv_flags & VIFF_TUNNEL)) {
/*
* Join the DVMRP multicast group on the interface.
* (This is not strictly necessary, since the kernel promiscuously
* receives IGMP packets addressed to ANY IP multicast group while
* multicast routing is enabled. However, joining the group allows
* this host to receive non-IGMP packets as well, such as 'pings'.)
*/
k_join(dvmrp_group, src);
/*
* Join the ALL-ROUTERS multicast group on the interface.
* This allows mtrace requests to loop back if they are run
* on the multicast router.
*/
k_join(allrtrs_group, src);
/*
* Install an entry in the routing table for the subnet to which
* the interface is connected.
*/
start_route_updates();
update_route(v->uv_subnet, v->uv_subnetmask, 0, 0, vifi);
for (p = v->uv_addrs; p; p = p->pa_next) {
start_route_updates();
update_route(p->pa_subnet, p->pa_subnetmask, 0, 0, vifi);
}
/*
* Until neighbors are discovered, assume responsibility for sending
* periodic group membership queries to the subnet. Send the first
* query.
*/
v->uv_flags |= VIFF_QUERIER;
send_igmp(src, allhosts_group, IGMP_HOST_MEMBERSHIP_QUERY,
(v->uv_flags & VIFF_IGMPV1) ? 0 :
IGMP_MAX_HOST_REPORT_DELAY * IGMP_TIMER_SCALE, 0, 0);
age_old_hosts();
}
v->uv_leaf_timer = LEAF_CONFIRMATION_TIME;
/*
* Send a probe via the new vif to look for neighbors.
*/
send_probe_on_vif(v);
}
/*
* Stop routing on the specified virtual interface.
*/
static void
stop_vif(vifi_t vifi)
{
struct uvif *v;
struct listaddr *a;
struct phaddr *p;
v = &uvifs[vifi];
if (!(v->uv_flags & VIFF_TUNNEL)) {
/*
* Depart from the DVMRP multicast group on the interface.
*/
k_leave(dvmrp_group, v->uv_lcl_addr);
/*
* Depart from the ALL-ROUTERS multicast group on the interface.
*/
k_leave(allrtrs_group, v->uv_lcl_addr);
/*
* Update the entry in the routing table for the subnet to which
* the interface is connected, to take into account the interface
* failure.
*/
start_route_updates();
update_route(v->uv_subnet, v->uv_subnetmask, UNREACHABLE, 0, vifi);
for (p = v->uv_addrs; p; p = p->pa_next) {
start_route_updates();
update_route(p->pa_subnet, p->pa_subnetmask, UNREACHABLE, 0, vifi);
}
/*
* Discard all group addresses. (No need to tell kernel;
* the k_del_vif() call, below, will clean up kernel state.)
*/
while (v->uv_groups != NULL) {
a = v->uv_groups;
v->uv_groups = a->al_next;
free((char *)a);
}
v->uv_flags &= ~VIFF_QUERIER;
}
/*
* Update the existing route entries to take into account the vif failure.
*/
delete_vif_from_routes(vifi);
/*
* Delete the interface from the kernel's vif structure.
*/
k_del_vif(vifi);
/*
* Discard all neighbor addresses.
*/
if (v->uv_neighbors)
vifs_with_neighbors--;
while (v->uv_neighbors != NULL) {
a = v->uv_neighbors;
v->uv_neighbors = a->al_next;
free((char *)a);
}
}
/*
* stop routing on all vifs
*/
void
stop_all_vifs(void)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *a;
struct vif_acl *acl;
for (vifi = 0; vifi < numvifs; vifi++) {
v = &uvifs[vifi];
while (v->uv_groups != NULL) {
a = v->uv_groups;
v->uv_groups = a->al_next;
free((char *)a);
}
while (v->uv_neighbors != NULL) {
a = v->uv_neighbors;
v->uv_neighbors = a->al_next;
free((char *)a);
}
while (v->uv_acl != NULL) {
acl = v->uv_acl;
v->uv_acl = acl->acl_next;
free((char *)acl);
}
}
}
/*
* Find the virtual interface from which an incoming packet arrived,
* based on the packet's source and destination IP addresses.
*/
vifi_t
find_vif(u_int32_t src, u_int32_t dst)
{
vifi_t vifi;
struct uvif *v;
struct phaddr *p;
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (!(v->uv_flags & (VIFF_DOWN|VIFF_DISABLED))) {
if (v->uv_flags & VIFF_TUNNEL) {
if (src == v->uv_rmt_addr && dst == v->uv_lcl_addr)
return(vifi);
}
else {
if ((src & v->uv_subnetmask) == v->uv_subnet &&
((v->uv_subnetmask == 0xffffffff) ||
(src != v->uv_subnetbcast)))
return(vifi);
for (p=v->uv_addrs; p; p=p->pa_next) {
if ((src & p->pa_subnetmask) == p->pa_subnet &&
((p->pa_subnetmask == 0xffffffff) ||
(src != p->pa_subnetbcast)))
return(vifi);
}
}
}
}
return (NO_VIF);
}
static void
age_old_hosts(void)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *g;
/*
* Decrement the old-hosts-present timer for each
* active group on each vif.
*/
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++)
for (g = v->uv_groups; g != NULL; g = g->al_next)
if (g->al_old)
g->al_old--;
}
/*
* Send group membership queries to all subnets for which I am querier.
*/
void
query_groups(void)
{
vifi_t vifi;
struct uvif *v;
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) {
if (v->uv_flags & VIFF_QUERIER) {
send_igmp(v->uv_lcl_addr, allhosts_group,
IGMP_HOST_MEMBERSHIP_QUERY,
(v->uv_flags & VIFF_IGMPV1) ? 0 :
IGMP_MAX_HOST_REPORT_DELAY * IGMP_TIMER_SCALE, 0, 0);
}
}
age_old_hosts();
}
/*
* Process an incoming host membership query
*/
void
accept_membership_query(u_int32_t src, u_int32_t dst, u_int32_t group, int tmo)
{
vifi_t vifi;
struct uvif *v;
if ((vifi = find_vif(src, dst)) == NO_VIF ||
(uvifs[vifi].uv_flags & VIFF_TUNNEL)) {
logit(LOG_INFO, 0,
"ignoring group membership query from non-adjacent host %s",
inet_fmt(src));
return;
}
v = &uvifs[vifi];
/*
* If we consider ourselves the querier for this vif, but hear a
* query from a router with a lower IP address, yield to them.
*
* This is done here as well as in the neighbor discovery in case
* there is a querier that doesn't speak DVMRP.
*
* XXX If this neighbor doesn't speak DVMRP, then we need to create
* some neighbor state for him so that we can time him out!
*/
if ((v->uv_flags & VIFF_QUERIER) &&
(ntohl(src) < ntohl(v->uv_lcl_addr))) {
v->uv_flags &= ~VIFF_QUERIER;
}
}
/*
* Process an incoming group membership report.
*/
void
accept_group_report(u_int32_t src, u_int32_t dst, u_int32_t group, int r_type)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *g;
if ((vifi = find_vif(src, dst)) == NO_VIF ||
(uvifs[vifi].uv_flags & VIFF_TUNNEL)) {
logit(LOG_INFO, 0,
"ignoring group membership report from non-adjacent host %s",
inet_fmt(src));
return;
}
v = &uvifs[vifi];
/*
* Look for the group in our group list; if found, reset its timer.
*/
for (g = v->uv_groups; g != NULL; g = g->al_next) {
if (group == g->al_addr) {
if (r_type == IGMP_v1_HOST_MEMBERSHIP_REPORT)
g->al_old = OLD_AGE_THRESHOLD;
#ifdef SNMP
g->al_genid = src;
#endif /* SNMP */
/** delete old timers, set a timer for expiration **/
g->al_timer = GROUP_EXPIRE_TIME;
if (g->al_query)
g->al_query = DeleteTimer(g->al_query);
if (g->al_timerid)
g->al_timerid = DeleteTimer(g->al_timerid);
g->al_timerid = SetTimer(vifi, g);
break;
}
}
/*
* If not found, add it to the list and update kernel cache.
*/
if (g == NULL) {
g = (struct listaddr *)malloc(sizeof(struct listaddr));
if (g == NULL) {
logit(LOG_ERR, 0, "ran out of memory"); /* fatal */
return;
}
g->al_addr = group;
if (r_type == IGMP_v2_HOST_MEMBERSHIP_REPORT)
g->al_old = 0;
else
g->al_old = OLD_AGE_THRESHOLD;
#ifdef SNMP
g->al_genid = src;
#endif
/** set a timer for expiration **/
g->al_query = 0;
g->al_timer = GROUP_EXPIRE_TIME;
time(&g->al_ctime);
g->al_timerid = SetTimer(vifi, g);
g->al_next = v->uv_groups;
v->uv_groups = g;
update_lclgrp(vifi, group);
}
/*
* Check if a graft is necessary for this group
*/
chkgrp_graft(vifi, group);
}
void
accept_leave_message(u_int32_t src, u_int32_t dst, u_int32_t group)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *g;
if ((vifi = find_vif(src, dst)) == NO_VIF ||
(uvifs[vifi].uv_flags & VIFF_TUNNEL)) {
logit(LOG_INFO, 0,
"ignoring group leave report from non-adjacent host %s",
inet_fmt(src));
return;
}
v = &uvifs[vifi];
if (!(v->uv_flags & VIFF_QUERIER) || (v->uv_flags & VIFF_IGMPV1))
return;
/*
* Look for the group in our group list in order to set up a short-timeout
* query.
*/
for (g = v->uv_groups; g != NULL; g = g->al_next) {
if (group == g->al_addr) {
logit(LOG_DEBUG, 0,
"[vif.c, _accept_leave_message] %d %ld\n",
g->al_old, g->al_query);
/* Ignore the leave message if there are old hosts present */
if (g->al_old)
return;
/* still waiting for a reply to a query, ignore the leave */
if (g->al_query)
return;
/** delete old timer set a timer for expiration **/
if (g->al_timerid)
g->al_timerid = DeleteTimer(g->al_timerid);
/** send a group specific querry **/
g->al_timer = LEAVE_EXPIRE_TIME;
send_igmp(v->uv_lcl_addr, g->al_addr,
IGMP_HOST_MEMBERSHIP_QUERY,
LEAVE_EXPIRE_TIME / 3 * IGMP_TIMER_SCALE,
g->al_addr, 0);
g->al_query = SetQueryTimer(g, vifi, g->al_timer / 3,
LEAVE_EXPIRE_TIME / 3 * IGMP_TIMER_SCALE);
g->al_timerid = SetTimer(vifi, g);
break;
}
}
}
/*
* Send a periodic probe on all vifs.
* Useful to determine one-way interfaces.
* Detect neighbor loss faster.
*/
void
probe_for_neighbors(void)
{
vifi_t vifi;
struct uvif *v;
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) {
if (!(v->uv_flags & (VIFF_DOWN|VIFF_DISABLED))) {
send_probe_on_vif(v);
}
}
}
/*
* Send a list of all of our neighbors to the requestor, `src'.
*/
void
accept_neighbor_request(u_int32_t src, u_int32_t dst)
{
vifi_t vifi;
struct uvif *v;
u_char *p, *ncount;
struct listaddr *la;
int datalen;
u_int32_t temp_addr, us, them = src;
/* Determine which of our addresses to use as the source of our response
* to this query.
*/
if (IN_MULTICAST(ntohl(dst))) { /* query sent to a multicast group */
int udp; /* find best interface to reply on */
struct sockaddr_in addr;
socklen_t addrlen = sizeof(addr);
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
addr.sin_len = sizeof addr;
#endif
addr.sin_addr.s_addr = dst;
addr.sin_port = htons(2000); /* any port over 1024 will do... */
if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
|| connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0
|| getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0) {
logit(LOG_WARNING, errno, "Determining local address");
close(udp);
return;
}
close(udp);
us = addr.sin_addr.s_addr;
} else /* query sent to us alone */
us = dst;
#define PUT_ADDR(a) temp_addr = ntohl(a); \
*p++ = temp_addr >> 24; \
*p++ = (temp_addr >> 16) & 0xFF; \
*p++ = (temp_addr >> 8) & 0xFF; \
*p++ = temp_addr & 0xFF;
p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
datalen = 0;
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) {
if (v->uv_flags & VIFF_DISABLED)
continue;
ncount = 0;
for (la = v->uv_neighbors; la; la = la->al_next) {
/* Make sure that there's room for this neighbor... */
if (datalen + (ncount == 0 ? 4 + 3 + 4 : 4) > MAX_DVMRP_DATA_LEN) {
send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS,
htonl(MROUTED_LEVEL), datalen);
p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
datalen = 0;
ncount = 0;
}
/* Put out the header for this neighbor list... */
if (ncount == 0) {
PUT_ADDR(v->uv_lcl_addr);
*p++ = v->uv_metric;
*p++ = v->uv_threshold;
ncount = p;
*p++ = 0;
datalen += 4 + 3;
}
PUT_ADDR(la->al_addr);
datalen += 4;
(*ncount)++;
}
}
if (datalen != 0)
send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS, htonl(MROUTED_LEVEL),
datalen);
}
/*
* Send a list of all of our neighbors to the requestor, `src'.
*/
void
accept_neighbor_request2(u_int32_t src, u_int32_t dst)
{
vifi_t vifi;
struct uvif *v;
u_char *p, *ncount;
struct listaddr *la;
int datalen;
u_int32_t us, them = src;
/* Determine which of our addresses to use as the source of our response
* to this query.
*/
if (IN_MULTICAST(ntohl(dst))) { /* query sent to a multicast group */
int udp; /* find best interface to reply on */
struct sockaddr_in addr;
socklen_t addrlen = sizeof(addr);
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
addr.sin_len = sizeof addr;
#endif
addr.sin_addr.s_addr = dst;
addr.sin_port = htons(2000); /* any port over 1024 will do... */
if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
|| connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0
|| getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0) {
logit(LOG_WARNING, errno, "Determining local address");
close(udp);
return;
}
close(udp);
us = addr.sin_addr.s_addr;
} else /* query sent to us alone */
us = dst;
p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
datalen = 0;
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) {
u_short vflags = v->uv_flags;
u_char rflags = 0;
if (vflags & VIFF_TUNNEL)
rflags |= DVMRP_NF_TUNNEL;
if (vflags & VIFF_SRCRT)
rflags |= DVMRP_NF_SRCRT;
if (vflags & VIFF_DOWN)
rflags |= DVMRP_NF_DOWN;
if (vflags & VIFF_DISABLED)
rflags |= DVMRP_NF_DISABLED;
if (vflags & VIFF_QUERIER)
rflags |= DVMRP_NF_QUERIER;
if (vflags & VIFF_LEAF)
rflags |= DVMRP_NF_LEAF;
ncount = 0;
la = v->uv_neighbors;
if (la == NULL) {
/*
* include down & disabled interfaces and interfaces on
* leaf nets.
*/
if (rflags & DVMRP_NF_TUNNEL)
rflags |= DVMRP_NF_DOWN;
if (datalen > MAX_DVMRP_DATA_LEN - 12) {
send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2,
htonl(MROUTED_LEVEL), datalen);
p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
datalen = 0;
}
*(u_int*)p = v->uv_lcl_addr;
p += 4;
*p++ = v->uv_metric;
*p++ = v->uv_threshold;
*p++ = rflags;
*p++ = 1;
*(u_int*)p = v->uv_rmt_addr;
p += 4;
datalen += 12;
} else {
for ( ; la; la = la->al_next) {
/* Make sure that there's room for this neighbor... */
if (datalen + (ncount == 0 ? 4+4+4 : 4) > MAX_DVMRP_DATA_LEN) {
send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2,
htonl(MROUTED_LEVEL), datalen);
p = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
datalen = 0;
ncount = 0;
}
/* Put out the header for this neighbor list... */
if (ncount == 0) {
*(u_int*)p = v->uv_lcl_addr;
p += 4;
*p++ = v->uv_metric;
*p++ = v->uv_threshold;
*p++ = rflags;
ncount = p;
*p++ = 0;
datalen += 4 + 4;
}
*(u_int*)p = la->al_addr;
p += 4;
datalen += 4;
(*ncount)++;
}
}
}
if (datalen != 0)
send_igmp(us, them, IGMP_DVMRP, DVMRP_NEIGHBORS2, htonl(MROUTED_LEVEL),
datalen);
}
void
accept_info_request(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
{
u_char *q;
int len;
int outlen = 0;
q = (u_char *) (send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
/* To be general, this must deal properly with breaking up over-sized
* packets. That implies passing a length to each function, and
* allowing each function to request to be called again. Right now,
* we're only implementing the one thing we are positive will fit into
* a single packet, so we wimp out.
*/
while (datalen > 0) {
len = 0;
switch (*p) {
case DVMRP_INFO_VERSION:
len = info_version((char *)q,
send_buflen - MIN_IP_HEADER_LEN - IGMP_MINLEN);
break;
case DVMRP_INFO_NEIGHBORS:
default:
logit(LOG_INFO, 0, "ignoring unknown info type %d", *p);
break;
}
*(q+1) = len++;
outlen += len * 4;
q += len * 4;
len = (*(p+1) + 1) * 4;
p += len;
datalen -= len;
}
if (outlen != 0)
send_igmp(INADDR_ANY, src, IGMP_DVMRP, DVMRP_INFO_REPLY,
htonl(MROUTED_LEVEL), outlen);
}
/*
* Information response -- return version string
*/
static int
info_version(char *p, size_t l)
{
int len;
extern char versionstring[];
if (l < 4 + strlen(versionstring) + 1)
return -1;
p[0] = DVMRP_INFO_VERSION;
/* skip over length */
p[2] = 0; /* zero out */
p[3] = 0; /* reserved fields */
strlcpy(p + 4, versionstring, l - 4);
len = strlen(versionstring);
return ((len + 3) / 4);
}
/*
* Process an incoming neighbor-list message.
*/
void
accept_neighbors(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
u_int32_t level)
{
logit(LOG_INFO, 0, "ignoring spurious DVMRP neighbor list from %s to %s",
inet_fmt(src), inet_fmt(dst));
}
/*
* Process an incoming neighbor-list message.
*/
void
accept_neighbors2(u_int32_t src, u_int32_t dst, u_char *p, int datalen,
u_int32_t level)
{
logit(LOG_INFO, 0, "ignoring spurious DVMRP neighbor list2 from %s to %s",
inet_fmt(src), inet_fmt(dst));
}
/*
* Process an incoming info reply message.
*/
void
accept_info_reply(u_int32_t src, u_int32_t dst, u_char *p, int datalen)
{
logit(LOG_INFO, 0, "ignoring spurious DVMRP info reply from %s to %s",
inet_fmt(src), inet_fmt(dst));
}
/*
* Update the neighbor entry for neighbor 'addr' on vif 'vifi'.
* 'msgtype' is the type of DVMRP message received from the neighbor.
* Return TRUE if 'addr' is a valid neighbor, FALSE otherwise.
*/
int
update_neighbor(vifi_t vifi, u_int32_t addr, int msgtype, char *p, int datalen, u_int32_t level)
{
struct uvif *v;
struct listaddr *n;
u_int32_t genid = 0;
u_int32_t router;
u_int32_t send_tables = 0;
int do_reset = FALSE;
int nflags;
v = &uvifs[vifi];
nflags = (level >> 16) & 0xff;
/*
* Confirm that 'addr' is a valid neighbor address on vif 'vifi'.
* IT IS ASSUMED that this was preceded by a call to find_vif(), which
* checks that 'addr' is either a valid remote tunnel endpoint or a
* non-broadcast address belonging to a directly-connected subnet.
* Therefore, here we check only that 'addr' is not our own address
* (due to an impostor or erroneous loopback) or an address of the form
* {subnet,0} ("the unknown host"). These checks are not performed in
* find_vif() because those types of address are acceptable for some
* types of IGMP message (such as group membership reports).
*/
if (!(v->uv_flags & VIFF_TUNNEL) &&
(addr == v->uv_lcl_addr ||
addr == v->uv_subnet )) {
logit(LOG_WARNING, 0,
"received DVMRP message from 'the unknown host' or self: %s",
inet_fmt(addr));
return (FALSE);
}
/*
* Look for addr in list of neighbors.
*/
for (n = v->uv_neighbors; n != NULL; n = n->al_next) {
if (addr == n->al_addr) {
break;
}
}
/*
* Found it. Reset its timer, and check for a version change
*/
if (n) {
n->al_timer = 0;
/*
* update the neighbors version and protocol number
* if changed => router went down and came up,
* so take action immediately.
*/
if ((n->al_pv != (level & 0xff)) ||
(n->al_mv != ((level >> 8) & 0xff))) {
do_reset = TRUE;
logit(LOG_DEBUG, 0,
"version change neighbor %s [old:%d.%d, new:%d.%d]",
inet_fmt(addr),
n->al_pv, n->al_mv, level&0xff, (level >> 8) & 0xff);
n->al_pv = level & 0xff;
n->al_mv = (level >> 8) & 0xff;
}
} else {
/*
* If not found, add it to the list. If the neighbor has a lower
* IP address than me, yield querier duties to it.
*/
logit(LOG_DEBUG, 0, "New neighbor %s on vif %d v%d.%d nf 0x%02x",
inet_fmt(addr), vifi,
level & 0xff, (level >> 8) & 0xff, (level >> 16) & 0xff);
n = (struct listaddr *)malloc(sizeof(struct listaddr));
if (n == NULL) {
logit(LOG_ERR, 0, "ran out of memory"); /* fatal */
return FALSE;
}
n->al_addr = addr;
n->al_pv = level & 0xff;
n->al_mv = (level >> 8) & 0xff;
n->al_genid = 0;
time(&n->al_ctime);
n->al_timer = 0;
n->al_next = v->uv_neighbors;
/*
* If we thought that we had no neighbors on this vif, send a route
* report to the vif. If this is just a new neighbor on the same
* vif, send the route report just to the new neighbor.
*/
if (v->uv_neighbors == NULL) {
send_tables = (v->uv_flags & VIFF_TUNNEL) ? addr : dvmrp_group;
vifs_with_neighbors++;
} else {
send_tables = addr;
}
v->uv_neighbors = n;
if (!(v->uv_flags & VIFF_TUNNEL) &&
ntohl(addr) < ntohl(v->uv_lcl_addr))
v->uv_flags &= ~VIFF_QUERIER;
}
/*
* Check if the router gen-ids are the same.
* Need to reset the prune state of the router if not.
* Also check for one-way interfaces by seeing if we are in our
* neighbor's list of known routers.
*/
if (msgtype == DVMRP_PROBE) {
/* Check genid neighbor flag. Also check version number; 3.3 and
* 3.4 didn't set this flag. */
if ((((level >> 16) & 0xff) & NF_GENID) ||
(((level & 0xff) == 3) && (((level >> 8) & 0xff) > 2))) {
int i;
if (datalen < 4) {
logit(LOG_WARNING, 0,
"received truncated probe message from %s (len %d)",
inet_fmt(addr), datalen);
return (FALSE);
}
for (i = 0; i < 4; i++)
((char *)&genid)[i] = *p++;
datalen -= 4;
if (n->al_genid == 0)
n->al_genid = genid;
else if (n->al_genid != genid) {
logit(LOG_DEBUG, 0,
"new genid neigbor %s on vif %d [old:%x, new:%x]",
inet_fmt(addr), vifi, n->al_genid, genid);
n->al_genid = genid;
do_reset = TRUE;
}
/*
* loop through router list and check for one-way ifs.
*/
v->uv_flags |= VIFF_ONEWAY;
while (datalen > 0) {
if (datalen < 4) {
logit(LOG_WARNING, 0,
"received truncated probe message from %s (len %d)",
inet_fmt(addr), datalen);
return (FALSE);
}
for (i = 0; i < 4; i++)
((char *)&router)[i] = *p++;
datalen -= 4;
if (router == v->uv_lcl_addr) {
v->uv_flags &= ~VIFF_ONEWAY;
break;
}
}
}
}
if (n->al_flags != nflags) {
n->al_flags = nflags;
if (n->al_flags & NF_LEAF) {
/*XXX If we have non-leaf neighbors then we know we shouldn't
* mark this vif as a leaf. For now we just count on other
* probes and/or reports resetting the timer. */
if (!v->uv_leaf_timer)
v->uv_leaf_timer = LEAF_CONFIRMATION_TIME;
} else {
/* If we get a leaf to non-leaf transition, we *must* update
* the routing table. */
if (v->uv_flags & VIFF_LEAF && send_tables == 0)
send_tables = addr;
v->uv_flags &= ~VIFF_LEAF;
v->uv_leaf_timer = 0;
}
}
if (do_reset) {
reset_neighbor_state(vifi, addr);
if (!send_tables)
send_tables = addr;
}
if (send_tables)
report(ALL_ROUTES, vifi, send_tables);
return (TRUE);
}
/*
* On every timer interrupt, advance the timer in each neighbor and
* group entry on every vif.
*/
void
age_vifs(void)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *a, *prev_a, *n;
u_int32_t addr;
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v ) {
if (v->uv_leaf_timer && (v->uv_leaf_timer -= TIMER_INTERVAL == 0)) {
v->uv_flags |= VIFF_LEAF;
}
for (prev_a = NULL, a = v->uv_neighbors; a != NULL;) {
if ((a->al_timer += TIMER_INTERVAL) < NEIGHBOR_EXPIRE_TIME) {
prev_a = a;
a = a->al_next;
continue;
}
/*
* Neighbor has expired; delete it from the neighbor list,
* delete it from the 'dominants' and 'subordinates arrays of
* any route entries and assume querier duties unless there is
* another neighbor with a lower IP address than mine.
*/
addr = a->al_addr;
if (a == v->uv_neighbors) { /* implies prev_a == NULL */
v->uv_neighbors = a->al_next;
free((char *)a);
a = v->uv_neighbors; /* prev_a stays NULL */
} else {
prev_a->al_next = a->al_next;
free((char *)a);
a = prev_a->al_next; /* prev_a stays the same */
}
delete_neighbor_from_routes(addr, vifi);
if (v->uv_neighbors == NULL)
vifs_with_neighbors--;
v->uv_leaf_timer = LEAF_CONFIRMATION_TIME;
if (!(v->uv_flags & VIFF_TUNNEL)) {
v->uv_flags |= VIFF_QUERIER;
for (n = v->uv_neighbors; n != NULL; n = n->al_next) {
if (ntohl(n->al_addr) < ntohl(v->uv_lcl_addr)) {
v->uv_flags &= ~VIFF_QUERIER;
}
if (!(n->al_flags & NF_LEAF)) {
v->uv_leaf_timer = 0;
}
}
}
}
}
}
/*
* Returns the neighbor info struct for a given neighbor
*/
struct listaddr *
neighbor_info(vifi_t vifi, u_int32_t addr)
{
struct listaddr *u;
for (u = uvifs[vifi].uv_neighbors; u; u = u->al_next)
if (u->al_addr == addr)
return u;
return NULL;
}
/*
* Print the contents of the uvifs array on file 'fp'.
*/
void
dump_vifs(FILE *fp)
{
vifi_t vifi;
struct uvif *v;
struct listaddr *a;
struct phaddr *p;
struct sioc_vif_req v_req;
fprintf(fp, "vifs_with_neighbors = %d\n", vifs_with_neighbors);
if (vifs_with_neighbors == 1)
fprintf(fp,"[This host is a leaf]\n\n");
fprintf(fp,
"\nVirtual Interface Table\n%s",
"Vif Name Local-Address ");
fprintf(fp,
"M Thr Rate Flags\n");
for (vifi = 0, v = uvifs; vifi < numvifs; vifi++, v++) {
fprintf(fp, "%2u %6s %-15s %6s: %-18s %2u %3u %5u ",
vifi,
v->uv_name,
inet_fmt(v->uv_lcl_addr),
(v->uv_flags & VIFF_TUNNEL) ?
"tunnel":
"subnet",
(v->uv_flags & VIFF_TUNNEL) ?
inet_fmt(v->uv_rmt_addr) :
inet_fmts(v->uv_subnet, v->uv_subnetmask),
v->uv_metric,
v->uv_threshold,
v->uv_rate_limit);
if (v->uv_flags & VIFF_ONEWAY) fprintf(fp, " one-way");
if (v->uv_flags & VIFF_DOWN) fprintf(fp, " down");
if (v->uv_flags & VIFF_DISABLED) fprintf(fp, " disabled");
if (v->uv_flags & VIFF_QUERIER) fprintf(fp, " querier");
if (v->uv_flags & VIFF_SRCRT) fprintf(fp, " src-rt");
if (v->uv_flags & VIFF_LEAF) fprintf(fp, " leaf");
if (v->uv_flags & VIFF_IGMPV1) fprintf(fp, " IGMPv1");
fprintf(fp, "\n");
if (v->uv_addrs != NULL) {
fprintf(fp, " alternate subnets: %s\n",
inet_fmts(v->uv_addrs->pa_subnet,
v->uv_addrs->pa_subnetmask));
for (p = v->uv_addrs->pa_next; p; p = p->pa_next) {
fprintf(fp, " %s\n",
inet_fmts(p->pa_subnet, p->pa_subnetmask));
}
}
if (v->uv_neighbors != NULL) {
fprintf(fp, " peers: %s (%d.%d) (0x%x)\n",
inet_fmt(v->uv_neighbors->al_addr),
v->uv_neighbors->al_pv, v->uv_neighbors->al_mv,
v->uv_neighbors->al_flags);
for (a = v->uv_neighbors->al_next; a != NULL; a = a->al_next) {
fprintf(fp, " %s (%d.%d) (0x%x)\n",
inet_fmt(a->al_addr), a->al_pv,
a->al_mv, a->al_flags);
}
}
if (v->uv_groups != NULL) {
fprintf(fp, " groups: %-15s\n",
inet_fmt(v->uv_groups->al_addr));
for (a = v->uv_groups->al_next; a != NULL; a = a->al_next) {
fprintf(fp, " %-15s\n",
inet_fmt(a->al_addr));
}
}
if (v->uv_acl != NULL) {
struct vif_acl *acl;
fprintf(fp, " boundaries: %-18s\n",
inet_fmts(v->uv_acl->acl_addr, v->uv_acl->acl_mask));
for (acl = v->uv_acl->acl_next; acl != NULL; acl = acl->acl_next) {
fprintf(fp, " : %-18s\n",
inet_fmts(acl->acl_addr, acl->acl_mask));
}
}
v_req.vifi = vifi;
if (ioctl(igmp_socket, SIOCGETVIFCNT, (char *)&v_req) < 0) {
logit(LOG_WARNING, 0,
"SIOCGETVIFCNT fails");
}
else {
fprintf(fp, " pkts in : %ld\n",
v_req.icount);
fprintf(fp, " pkts out: %ld\n",
v_req.ocount);
}
fprintf(fp, "\n");
}
fprintf(fp, "\n");
}
/*
* Time out record of a group membership on a vif
*/
static void
DelVif(void *arg)
{
cbk_t *cbk = (cbk_t *)arg;
vifi_t vifi = cbk->vifi;
struct uvif *v = &uvifs[vifi];
struct listaddr *a, **anp, *g = cbk->g;
/*
* Group has expired
* delete all kernel cache entries with this group
*/
if (g->al_query)
DeleteTimer(g->al_query);
delete_lclgrp(vifi, g->al_addr);
anp = &(v->uv_groups);
while ((a = *anp) != NULL) {
if (a == g) {
*anp = a->al_next;
free((char *)a);
} else {
anp = &a->al_next;
}
}
free(cbk);
}
/*
* Set a timer to delete the record of a group membership on a vif.
*/
static int
SetTimer(vifi_t vifi, struct listaddr *g)
{
cbk_t *cbk;
cbk = (cbk_t *) malloc(sizeof(cbk_t));
cbk->g = g;
cbk->vifi = vifi;
return timer_setTimer(g->al_timer, (cfunc_t)DelVif, (void *)cbk);
}
/*
* Delete a timer that was set above.
*/
static int
DeleteTimer(int id)
{
timer_clearTimer(id);
return 0;
}
/*
* Send a group-specific query.
*/
static void
SendQuery(void *arg)
{
cbk_t *cbk = (cbk_t *)arg;
struct uvif *v = &uvifs[cbk->vifi];
send_igmp(v->uv_lcl_addr, cbk->g->al_addr,
IGMP_HOST_MEMBERSHIP_QUERY,
cbk->q_time, cbk->g->al_addr, 0);
cbk->g->al_query = 0;
free(cbk);
}
/*
* Set a timer to send a group-specific query.
*/
static int
SetQueryTimer(struct listaddr *g, vifi_t vifi, int to_expire, int q_time)
{
cbk_t *cbk;
cbk = (cbk_t *) malloc(sizeof(cbk_t));
cbk->g = g;
cbk->q_time = q_time;
cbk->vifi = vifi;
return timer_setTimer(to_expire, (cfunc_t)SendQuery, (void *)cbk);
}
Reference in New Issue View Git Blame Copy Permalink