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NetBSD/usr.sbin/mrouted/vif.c

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/* $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);
}
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