void NS_CLASS recvAODVUUPacket(Packet * p)
{
int len, i, ttl = 0;
u_int32_t src, dst;
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
hdr_aodvuu *ah = HDR_AODVUU(p);
src = ih->saddr();
dst = ih->daddr();
len = ch->size() - IP_HDR_LEN;
ttl = ih->ttl();
AODV_msg *aodv_msg = (AODV_msg *) recv_buf;
/* Only handle AODVUU packets */
assert(ch->ptype() == PT_AODVUU);
/* Only process incoming packets */
assert(ch->direction() == hdr_cmn::UP);
/* Copy message to receive buffer */
memcpy(recv_buf, ah, RECV_BUF_SIZE);
/* Drop or deallocate packet, depending on the TTL */
/* if (ttl == 1) */
/* drop(p, DROP_RTR_TTL); */
/* else */
Packet::free(p);
/* Ignore messages generated locally */
for (i = 0; i < MAX_NR_INTERFACES; i++)
if (this_host.devs[i].enabled &&
memcmp(&src, &this_host.devs[i].ipaddr, sizeof(u_int32_t)) == 0)
return;
aodv_socket_process_packet(aodv_msg, len, src, dst, ttl, NS_IFINDEX);
}
void NS_CLASS recvAODVUUPacket(Packet * p)
{
int len, i, ttl = 0;
struct in_addr src, dst;
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
hdr_aodvuu *ah = HDR_AODVUU(p);
src.s_addr = ih->saddr();
dst.s_addr = ih->daddr();
len = ch->size() - IP_HDR_LEN;
ttl = ih->ttl();
AODV_msg *aodv_msg = (AODV_msg *) recv_buf;
/* Only handle AODVUU packets */
assert(ch->ptype() == PT_AODVUU);
/* Only process incoming packets */
assert(ch->direction() == hdr_cmn::UP);
/* Copy message to receive buffer */
memcpy(recv_buf, ah, RECV_BUF_SIZE);
/* Deallocate packet, we have the information we need... */
Packet::free(p);
/* Ignore messages generated locally */
for (i = 0; i < MAX_NR_INTERFACES; i++)
if (this_host.devs[i].enabled &&
memcmp(&src, &this_host.devs[i].ipaddr,
sizeof(struct in_addr)) == 0)
return;
aodv_socket_process_packet(aodv_msg, len, src, dst, ttl, NS_IFINDEX);
}
static void packet_input(int fd)
#endif
{
rt_table_t *fwd_rt, *rev_rt, *next_hop_rt = NULL;
struct in_addr dest_addr, src_addr;
u_int8_t rreq_flags = 0;
unsigned int ifindex;
struct ip_data *ipd = NULL;
int pkt_flags = 0;
#ifdef NS_PORT
ifindex = NS_IFINDEX; /* Always use ns interface */
fwd_rt = NULL; /* For broadcast we provide no next hop */
ipd = NULL; /* No ICMP messaging */
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
src_addr.s_addr = ih->saddr();
dest_addr.s_addr = ih->daddr();
/* If this is a TCP packet and we don't have a route, we should
set the gratuituos flag in the RREQ. */
if (ch->ptype() == PT_TCP) {
rreq_flags |= RREQ_GRATUITOUS;
}
#else
int status;
char buf[sizeof(struct nlmsghdr)+sizeof(ipq_packet_msg_t)+BUFSIZE];
char *dev_name;
ipq_packet_msg_t *pkt;
struct iphdr *ip;
struct udphdr *udp;
struct icmphdr *icmp = NULL;
status = ipq_read(h, buf, sizeof(buf), -1);
if (status < 0) {
DEBUG(LOG_DEBUG, 0, "%s", ipq_errstr());
ipq_perror(NULL);
return;
}
if (ipq_message_type(buf) == NLMSG_ERROR) {
fprintf(stderr,
"ERROR packet_input: Check that the ip_queue.o module is loaded.\n");
die(h);
}
pkt = ipq_get_packet(buf);
#ifdef DEBUG_PACKET
DEBUG(LOG_DEBUG, 0, "Protocol %u indev=%s outdev=%s\n",
pkt->hw_protocol, pkt->indev_name, pkt->outdev_name);
#endif
if (pkt->hook == 0)
dev_name = pkt->indev_name;
else if (pkt->hook == 3)
dev_name = pkt->outdev_name;
else
dev_name = NULL;
/* We know from kaodv.c that this is an IP packet */
ip = (struct iphdr *) pkt->payload;
dest_addr.s_addr = ip->daddr;
src_addr.s_addr = ip->saddr;
switch (ip->protocol) {
/* Don't process AODV control packets (UDP on port 654). They
are accounted for on the aodv socket */
case IPPROTO_UDP:
udp = (struct udphdr *) ((char *) ip + (ip->ihl << 2));
if (ntohs(udp->dest) == AODV_PORT || ntohs(udp->source) == AODV_PORT)
goto accept;
break;
/* If this is a TCP packet and we don't have a route, we should
set the gratuituos flag in the RREQ. */
case IPPROTO_TCP:
rreq_flags |= RREQ_GRATUITOUS;
break;
/* We set the gratuitous flag also on ICMP ECHO requests, since
the destination will also need a route back for the reply... */
case IPPROTO_ICMP:
icmp = (struct icmphdr *) ((char *) ip + (ip->ihl << 2));
if (icmp->type == ICMP_ECHO)
rreq_flags |= RREQ_GRATUITOUS;
#ifdef DEBUG_PACKET
DEBUG(LOG_INFO, 0, "setting G flag for RREQ to %s",
ip_to_str(dest_addr));
#endif
break;
#ifdef CONFIG_GATEWAY
case IPPROTO_MIPE:
if (internet_gw_mode) {
ip = ip_pkt_decapsulate(ip);
if (ip == NULL) {
DEBUG(LOG_ERR, 0, "Decapsulation failed...");
exit(-1);
}
pkt_flags |= PKT_DEC;
}
break;
#endif /* CONFIG_GATEWAY */
}
#ifdef DEBUG_PACKET
DEBUG(LOG_INFO, 0, "pkt to %s", ip_to_str(dest_addr));
#endif
if (dev_name) {
ifindex = name2index(dev_name);
if (ifindex < 0) {
DEBUG(LOG_ERR, 0, "name2index error!");
return;
}
} else
ifindex = 0;
#endif /* NS_PORT */
/* If the packet is not interesting we just let it go through... */
if (dest_addr.s_addr == AODV_BROADCAST ||
dest_addr.s_addr == DEV_IFINDEX(ifindex).broadcast.s_addr) {
#ifdef NS_PORT
/* Limit Non AODV broadcast packets (Rolf Winter
* <[email protected]). */
ih->ttl() = ih->ttl() - 1;
if(ih->ttl() < 1)
Packet::free(p);
else
sendPacket(p, dest_addr, 0.0);
return;
#else
goto accept;
#endif
}
/* Find the entry of the neighboring node and the destination (if any). */
rev_rt = rt_table_find(src_addr);
fwd_rt = rt_table_find(dest_addr);
#ifdef CONFIG_GATEWAY
/* Check if we have a route and it is an Internet destination (Should be
* encapsulated and routed through the gateway). */
if (fwd_rt && (fwd_rt->state == VALID) &&
(fwd_rt->flags & RT_INET_DEST)) {
/* The destination should be relayed through the IG */
rt_table_update_timeout(fwd_rt, ACTIVE_ROUTE_TIMEOUT);
#ifdef NS_PORT
p = pkt_encapsulate(p, fwd_rt->next_hop);
if (p == NULL) {
DEBUG(LOG_ERR, 0, "IP Encapsulation failed!");
return;
}
/* Update pointers to headers */
ch = HDR_CMN(p);
ih = HDR_IP(p);
#else
ip = ip_pkt_encapsulate(ip, fwd_rt->next_hop, BUFSIZE);
if (ip == NULL) {
DEBUG(LOG_ERR, 0, "Minimal IP Encapsulation failed!");
exit(-1);
}
#endif
dest_addr = fwd_rt->next_hop;
fwd_rt = rt_table_find(dest_addr);
pkt_flags |= PKT_ENC;
}
#endif /* CONFIG_GATEWAY */
/* UPDATE TIMERS on active forward and reverse routes... */
/* When forwarding a packet, we update the lifetime of the
destination's routing table entry, as well as the entry for the
next hop neighbor (if not the same). AODV draft 10, section
6.2. */
if (fwd_rt && fwd_rt->state == VALID &&
dest_addr.s_addr != DEV_IFINDEX(ifindex).ipaddr.s_addr) {
rt_table_update_timeout(fwd_rt, ACTIVE_ROUTE_TIMEOUT);
next_hop_rt = rt_table_find(fwd_rt->next_hop);
if (next_hop_rt && next_hop_rt->state == VALID &&
next_hop_rt->dest_addr.s_addr != fwd_rt->dest_addr.s_addr)
rt_table_update_timeout(next_hop_rt, ACTIVE_ROUTE_TIMEOUT);
}
/* Also update the reverse route and reverse next hop along the
path back, since routes between originators and the destination
are expected to be symmetric. */
if (rev_rt && rev_rt->state == VALID) {
rt_table_update_timeout(rev_rt, ACTIVE_ROUTE_TIMEOUT);
next_hop_rt = rt_table_find(rev_rt->next_hop);
if (next_hop_rt && next_hop_rt->state == VALID &&
rev_rt && next_hop_rt->dest_addr.s_addr != rev_rt->dest_addr.s_addr)
rt_table_update_timeout(next_hop_rt, ACTIVE_ROUTE_TIMEOUT);
/* Update HELLO timer of next hop neighbor if active */
if (!llfeedback && next_hop_rt->hello_timer.used) {
struct timeval now;
gettimeofday(&now, NULL);
hello_update_timeout(next_hop_rt, &now,
ALLOWED_HELLO_LOSS * HELLO_INTERVAL);
}
}
/* OK, the timeouts have been updated. Now see if either: 1. The
packet is for this node -> ACCEPT. 2. The packet is not for this
node -> Send RERR (someone want's this node to forward packets
although there is no route) or Send RREQ. */
/* If the packet is destined for this node, then just accept it. */
if (memcmp(&dest_addr, &DEV_IFINDEX(ifindex).ipaddr,
sizeof(struct in_addr)) == 0) {
#ifdef NS_PORT
ch->size() -= IP_HDR_LEN; // cut off IP header size 4/7/99 -dam
target_->recv(p, (Handler*)0);
p = 0;
return;
#else
goto accept;
#endif
}
if (!fwd_rt || fwd_rt->state == INVALID ||
(fwd_rt->hcnt == 1 && (fwd_rt->flags & RT_UNIDIR))) {
/* Check if the route is marked for repair or is INVALID. In
* that case, do a route discovery. */
if (fwd_rt && (fwd_rt->flags & RT_REPAIR))
goto route_discovery;
/* If a packet is received on the NF_IP_PRE_ROUTING hook,
i.e. inbound on the interface and we don't have a route to
the destination, we should send an RERR to the source and
then drop the package... */
/* NF_IP_PRE_ROUTING = 0 */
#ifdef NS_PORT
#define PACKET_IS_INBOUND ch->direction() == hdr_cmn::UP
#else
#define PACKET_IS_INBOUND pkt->hook == 0
#endif
if (PACKET_IS_INBOUND) {
struct in_addr rerr_dest;
RERR *rerr;
#ifdef NS_PORT
struct in_addr nh;
nh.s_addr = ch->prev_hop_;
DEBUG(LOG_DEBUG, 0,
"No route, src=%s dest=%s prev_hop=%s - DROPPING!",
ip_to_str(src_addr), ip_to_str(dest_addr),
ip_to_str(nh));
#endif
if (fwd_rt) {
rerr = rerr_create(0, fwd_rt->dest_addr,
fwd_rt->dest_seqno);
rt_table_update_timeout(fwd_rt, DELETE_PERIOD);
} else
rerr = rerr_create(0, dest_addr, 0);
DEBUG(LOG_DEBUG, 0, "Sending RERR to prev hop %s for unknown dest %s", ip_to_str(src_addr), ip_to_str(dest_addr));
/* Unicast the RERR to the source of the data transmission
* if possible, otherwise we broadcast it. */
if (rev_rt && rev_rt->state == VALID)
rerr_dest = rev_rt->next_hop;
else
rerr_dest.s_addr = AODV_BROADCAST;
aodv_socket_send((AODV_msg *) rerr, rerr_dest,
RERR_CALC_SIZE(rerr), 1, &DEV_IFINDEX(ifindex));
if (wait_on_reboot) {
DEBUG(LOG_DEBUG, 0, "Wait on reboot timer reset.");
timer_set_timeout(&worb_timer, DELETE_PERIOD);
}
#ifdef NS_PORT
/* DEBUG(LOG_DEBUG, 0, "Dropping pkt uid=%d", ch->uid()); */
drop(p, DROP_RTR_NO_ROUTE);
#else
status = ipq_set_verdict(h, pkt->packet_id, NF_DROP, 0, NULL);
if (status < 0)
die(h);
#endif
return;
}
route_discovery:
/* Buffer packets... Packets are queued by the ip_queue.o
module already. We only need to save the handle id, and
return the proper verdict when we know what to do... */
#ifdef NS_PORT
packet_queue_add(p, dest_addr);
#else
packet_queue_add(pkt->packet_id, dest_addr, ip);
#ifdef CONFIG_GATEWAY
/* In gateway mode we handle packets in userspace */
ipq_set_verdict(h, pkt->packet_id, NF_DROP, 0, NULL);
#endif
/* Already seeking the destination? Then do not allocate any
memory or generate a RREQ. */
if (seek_list_find(dest_addr))
return;
/* If the request is generated locally by an application, we save
the IP header + 64 bits of data for sending an ICMP Destination
Host Unreachable in case we don't find a route... */
if (src_addr.s_addr == DEV_IFINDEX(ifindex).ipaddr.s_addr && ip &&
pkt->data_len >= (ip->ihl << 2) + 8) {
ipd = (struct ip_data *) malloc(sizeof(struct ip_data));
if (ipd == NULL) {
perror("Malloc for IP data failed!");
exit(-1);
}
/* IP header + 64 bits data (8 bytes) */
ipd->len = (ip->ihl << 2) + 8;
memcpy(ipd->data, ip, ipd->len);
} else
ipd = NULL;
#endif
if (fwd_rt && (fwd_rt->flags & RT_REPAIR))
rreq_local_repair(fwd_rt, src_addr, ipd);
else
rreq_route_discovery(dest_addr, rreq_flags, ipd);
return;
} else {
#ifdef NS_PORT
/* DEBUG(LOG_DEBUG, 0, "Sending pkt uid=%d", ch->uid()); */
sendPacket(p, fwd_rt->next_hop, 0.0);
#else
accept:
if (pkt_flags & PKT_ENC || (pkt_flags & PKT_DEC))
status = ipq_set_verdict(h, pkt->packet_id, NF_ACCEPT,
ntohs(ip->tot_len), (unsigned char *)ip);
else
status = ipq_set_verdict(h, pkt->packet_id, NF_ACCEPT, 0, NULL);
if (status < 0)
die(h);
#endif
/* When forwarding data, make sure we are sending HELLO messages */
gettimeofday(&this_host.fwd_time, NULL);
if (!llfeedback && optimized_hellos)
hello_start();
}
}
void NS_CLASS aodv_socket_send(AODV_msg * aodv_msg, u_int32_t dst, int len,
u_int8_t ttl, struct dev_info *dev)
{
int retval = 0;
struct timeval now;
/* Rate limit stuff: */
#ifndef NS_PORT
struct sockaddr_in dst_addr;
#ifdef RAW_SOCKET
struct iphdr *iph;
struct udphdr *udph;
if (wait_on_reboot && aodv_msg->type == AODV_RREP)
return;
/* Create a IP header around the packet... The AODV msg is already
located in the send buffer and referenced by the in parameter
"aodv_msg". */
iph = (struct iphdr *) send_buf;
iph->tot_len = htons(IPHDR_SIZE + sizeof(struct udphdr) + len);
iph->saddr = htonl(dev->ipaddr);
iph->daddr = htonl(dst);
iph->ttl = ttl;
udph = (struct udphdr *) (send_buf + IPHDR_SIZE);
udph->len = htons(len + sizeof(struct udphdr));
#else
/* If we are in waiting phase after reboot, don't send any control
messages */
if (wait_on_reboot)
return;
/* Set the ttl we want to send with */
if (setsockopt(dev->sock, SOL_IP, IP_TTL, &ttl, sizeof(ttl)) < 0) {
log(LOG_WARNING, 0, __FUNCTION__, "Failed to set TTL!!!");
return;
}
#endif /* RAW_SOCKET */
memset(&dst_addr, 0, sizeof(dst_addr));
dst_addr.sin_family = AF_INET;
dst_addr.sin_addr.s_addr = htonl(dst);
dst_addr.sin_port = htons(AODV_PORT);
#else
/*
NS_PORT: Sending of AODV_msg messages to other AODV-UU routing agents
by encapsulating them in a Packet.
Note: This method is _only_ for sending AODV packets to other routing
agents, _not_ for forwarding "regular" IP packets!
*/
/* If we are in waiting phase after reboot, don't send any RREPs */
if (wait_on_reboot && aodv_msg->type == AODV_RREP)
return;
/*
NS_PORT: Don't allocate packet until now. Otherwise packet uid
(unique ID) space is unnecessarily exhausted at the beginning of
the simulation, resulting in uid:s starting at values greater than 0.
*/
Packet *p = allocpkt();
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
hdr_aodvuu *ah = HDR_AODVUU(p);
// Clear AODVUU part of packet
memset(ah, '\0', ah->size());
// Copy message contents into packet
memcpy(ah, aodv_msg, len);
// Set common header fields
ch->ptype() = PT_AODVUU;
ch->direction() = hdr_cmn::DOWN;
ch->size() = IP_HDR_LEN + len;
ch->iface() = -2;
ch->error() = 0;
ch->prev_hop_ = (nsaddr_t) dev->ipaddr;
// Set IP header fields
ih->saddr() = (nsaddr_t) dev->ipaddr;
ih->daddr() = (nsaddr_t) dst;
ih->ttl() = ttl;
// Note: Port number for routing agents, not AODV port number!
ih->sport() = RT_PORT;
ih->dport() = RT_PORT;
// Fake success
retval = len;
#endif /* NS_PORT */
/* If rate limiting is enabled, check if we are sending either a
RREQ or a RERR. In that case, drop the outgoing control packet
if the time since last transmit of that type of packet is less
than the allowed RATE LIMIT time... */
if (ratelimit) {
gettimeofday(&now, NULL);
switch (aodv_msg->type) {
case AODV_RREQ:
if (timeval_diff(&now, &time_last_rreq) < 1000 / RREQ_RATELIMIT) {
DEBUG(LOG_DEBUG, 0, "Dropping RREQ due to RATELIMIT %ld ms",
timeval_diff(&now, &time_last_rreq));
return;
}
memcpy(&time_last_rreq, &now, sizeof(struct timeval));
break;
case AODV_RERR:
if (timeval_diff(&now, &time_last_rerr) < 1000 / RERR_RATELIMIT) {
DEBUG(LOG_DEBUG, 0, "Dropping RERR due to RATELIMIT %ld ms",
timeval_diff(&now, &time_last_rerr));
return;
}
memcpy(&time_last_rerr, &now, sizeof(struct timeval));
break;
}
}
/* Alternative RATE LIMIT ALGORITHM: This algorithm will start to
* count time (forward 1 second) from the first packet sent. If more
* than RATELIMIT allowed packets are sent during that period, the
* last packet is dropped and the packet counter and time are
* reset. The time and packet count are also reset if 1 second lasts
* without the limit being reached... The problem is that if there are
* many packets at the end of an "interval" and at the start of the
* next, although the limit is not reached in either interval, there
* can be more than RATELIMIT packets sent if the second half of the
* first interval is joined with the first of the following
* interval... */
/* if (ratelimit) { */
/* gettimeofday(&now, NULL); */
/* switch (aodv_msg->type) { */
/* case AODV_RREQ: */
/* if (timeval_diff(&now, &time_last_rreq) > 1000) { */
/* num_rreq = 1; */
/* memcpy(&time_last_rreq, &now, sizeof(struct timeval)); */
/* } else { */
/* num_rreq++; */
/* DEBUG(LOG_DEBUG, 0, "RATELIMIT RREQ: time=%ld ms num=%d", */
/* timeval_diff(&now, &time_last_rreq), num_rreq); */
/* if (num_rreq > RREQ_RATELIMIT) { */
/* num_rreq = 0; */
/* DEBUG(LOG_DEBUG, 0, "Dropping RREQ due to RATELIMIT"); */
/* return; */
/* } */
/* } */
/* break; */
/* case AODV_RERR: */
/* if (timeval_diff(&now, &time_last_rerr) > 1000) { */
/* num_rerr = 1; */
/* memcpy(&time_last_rerr, &now, sizeof(struct timeval)); */
/* } else { */
/* num_rerr++; */
/* DEBUG(LOG_DEBUG, 0, "RATELIMIT RERR: time=%ld ms num=%d", */
/* timeval_diff(&now, &time_last_rerr), num_rerr); */
/* if (num_rerr > RERR_RATELIMIT) { */
/* num_rerr = 0; */
/* DEBUG(LOG_DEBUG, 0, "Dropping RERR due to RATELIMIT"); */
/* return; */
/* } */
/* } */
/* break; */
/* } */
/* } */
/* If we broadcast this message we update the time of last broadcast
to prevent unnecessary broadcasts of HELLO msg's */
if (dst == AODV_BROADCAST) {
gettimeofday(&this_host.bcast_time, NULL);
#ifdef NS_PORT
ch->addr_type() = NS_AF_NONE;
sendPacket(p, 0, 0.0);
#else
retval = sendto(dev->sock, send_buf, len, 0,
(struct sockaddr *) &dst_addr, sizeof(dst_addr));
if (retval < 0) {
log(LOG_WARNING, errno, __FUNCTION__, "Failed send to %s",
ip_to_str(dst));
return;
}
#endif
} else {
#ifdef NS_PORT
ch->addr_type() = NS_AF_INET;
/* We trust the decision of next hop for all AODV messages... */
/* Add jitter, even for unicast control messages. */
sendPacket(p, dst, 0.03 * Random::uniform());
#else
retval = sendto(dev->sock, send_buf, len, 0,
(struct sockaddr *) &dst_addr, sizeof(dst_addr));
if (retval < 0) {
log(LOG_WARNING, errno, __FUNCTION__, "Failed send to %s",
ip_to_str(dst));
return;
}
#endif
}
/* Do not print hello msgs... */
if (!(aodv_msg->type == AODV_RREP && (dst == AODV_BROADCAST)))
DEBUG(LOG_INFO, 0, "AODV msg to %s ttl=%d (%d bytes)",
ip_to_str(dst), ttl, retval);
return;
}
void NS_CLASS aodv_socket_send(AODV_msg * aodv_msg, struct in_addr dst,
int len, u_int8_t ttl, struct dev_info *dev)
{
int retval = 0;
struct timeval now;
/* Rate limit stuff: */
#ifndef NS_PORT
struct sockaddr_in dst_addr;
if (wait_on_reboot && aodv_msg->type == AODV_RREP)
return;
memset(&dst_addr, 0, sizeof(dst_addr));
dst_addr.sin_family = AF_INET;
dst_addr.sin_addr = dst;
dst_addr.sin_port = htons(AODV_PORT);
/* Set ttl */
if (setsockopt(dev->sock, SOL_IP, IP_TTL, &ttl, sizeof(ttl)) < 0) {
alog(LOG_WARNING, 0, __FUNCTION__, "ERROR setting ttl!");
return;
}
#else
/*
NS_PORT: Sending of AODV_msg messages to other AODV-UU routing agents
by encapsulating them in a Packet.
Note: This method is _only_ for sending AODV packets to other routing
agents, _not_ for forwarding "regular" IP packets!
*/
/* If we are in waiting phase after reboot, don't send any RREPs */
if (wait_on_reboot && aodv_msg->type == AODV_RREP)
return;
/*
NS_PORT: Don't allocate packet until now. Otherwise packet uid
(unique ID) space is unnecessarily exhausted at the beginning of
the simulation, resulting in uid:s starting at values greater than 0.
*/
Packet *p = allocpkt();
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
hdr_aodvuu *ah = HDR_AODVUU(p);
// Clear AODVUU part of packet
memset(ah, '\0', ah->size());
// Copy message contents into packet
memcpy(ah, aodv_msg, len);
// Set common header fields
ch->ptype() = PT_AODVUU;
ch->direction() = hdr_cmn::DOWN;
ch->size() = IP_HDR_LEN + len;
ch->iface() = -2;
ch->error() = 0;
ch->prev_hop_ = (nsaddr_t) dev->ipaddr.s_addr;
// Set IP header fields
ih->saddr() = (nsaddr_t) dev->ipaddr.s_addr;
ih->daddr() = (nsaddr_t) dst.s_addr;
ih->ttl() = ttl;
// Note: Port number for routing agents, not AODV port number!
ih->sport() = RT_PORT;
ih->dport() = RT_PORT;
// Fake success
retval = len;
#endif /* NS_PORT */
/* If rate limiting is enabled, check if we are sending either a
RREQ or a RERR. In that case, drop the outgoing control packet
if the time since last transmit of that type of packet is less
than the allowed RATE LIMIT time... */
if (ratelimit) {
gettimeofday(&now, NULL);
switch (aodv_msg->type) {
case AODV_RREQ:
if (num_rreq == (RREQ_RATELIMIT - 1)) {
if (timeval_diff(&now, &rreq_ratel[0]) < 1000) {
DEBUG(LOG_DEBUG, 0, "RATELIMIT: Dropping RREQ %ld ms",
timeval_diff(&now, &rreq_ratel[0]));
return;
} else {
memmove(rreq_ratel, &rreq_ratel[1],
sizeof(struct timeval) * (num_rreq - 1));
memcpy(&rreq_ratel[num_rreq - 1], &now,
sizeof(struct timeval));
}
} else {
memcpy(&rreq_ratel[num_rreq], &now, sizeof(struct timeval));
num_rreq++;
}
break;
case AODV_RERR:
if (num_rerr == (RERR_RATELIMIT - 1)) {
if (timeval_diff(&now, &rerr_ratel[0]) < 1000) {
DEBUG(LOG_DEBUG, 0, "RATELIMIT: Dropping RERR %ld ms",
timeval_diff(&now, &rerr_ratel[0]));
return;
} else {
memmove(rerr_ratel, &rerr_ratel[1],
sizeof(struct timeval) * (num_rerr - 1));
memcpy(&rerr_ratel[num_rerr - 1], &now,
sizeof(struct timeval));
}
} else {
memcpy(&rerr_ratel[num_rerr], &now, sizeof(struct timeval));
num_rerr++;
}
break;
}
}
/* If we broadcast this message we update the time of last broadcast
to prevent unnecessary broadcasts of HELLO msg's */
if (dst.s_addr == AODV_BROADCAST) {
gettimeofday(&this_host.bcast_time, NULL);
#ifdef NS_PORT
ch->addr_type() = NS_AF_NONE;
sendPacket(p, dst, 0.0);
#else
retval = sendto(dev->sock, send_buf, len, 0,
(struct sockaddr *) &dst_addr, sizeof(dst_addr));
if (retval < 0) {
alog(LOG_WARNING, errno, __FUNCTION__, "Failed send to bc %s",
ip_to_str(dst));
return;
}
#endif
} else {
#ifdef NS_PORT
ch->addr_type() = NS_AF_INET;
/* We trust the decision of next hop for all AODV messages... */
if (dst.s_addr == AODV_BROADCAST)
sendPacket(p, dst, 0.001 * Random::uniform());
else
sendPacket(p, dst, 0.0);
#else
retval = sendto(dev->sock, send_buf, len, 0,
(struct sockaddr *) &dst_addr, sizeof(dst_addr));
if (retval < 0) {
alog(LOG_WARNING, errno, __FUNCTION__, "Failed send to %s",
ip_to_str(dst));
return;
}
#endif
}
/* Do not print hello msgs... */
if (!(aodv_msg->type == AODV_RREP && (dst.s_addr == AODV_BROADCAST)))
DEBUG(LOG_INFO, 0, "AODV msg to %s ttl=%d size=%u",
ip_to_str(dst), ttl, retval, len);
return;
}
static void packet_input(int fd)
#endif
{
rt_table_t *fwd_rt, *rev_rt, *repair_rt, *next_hop_rt;
u_int32_t dest_addr, src_addr;
u_int8_t rreq_flags = 0;
unsigned int ifindex;
struct ip_data *ipd = NULL;
#ifdef NS_PORT
ifindex = NS_IFINDEX; // Always use ns interface
fwd_rt = NULL; // In case of broadcast we provide no next hop
ipd = NULL; // No ICMP messaging
struct hdr_cmn *ch = HDR_CMN(p);
struct hdr_ip *ih = HDR_IP(p);
src_addr = ih->saddr();
dest_addr = ih->daddr();
/*
Any packets with our IP address as destination arriving here are
packets that weren't caught by any agent attached to the node.
Throw away those.
*/
if (dest_addr == DEV_IFINDEX(ifindex).ipaddr) {
DEBUG(LOG_WARNING, 0,
"processPacket: Received orphan packet. Throwing it away.");
Packet::free(p);
return;
}
/* If this is a TCP packet and we don't have a route, we should
set the gratuituos flag in the RREQ. */
if (ch->ptype() == PT_TCP) {
rreq_flags |= RREQ_GRATUITOUS;
}
#else
int status;
char buf[BUFSIZE], *dev_name;
ipq_packet_msg_t *pkt;
struct iphdr *ip;
struct udphdr *udp;
struct icmphdr *icmp = NULL;
ipq_read(h, buf, BUFSIZE, 0);
status = ipq_message_type(buf);
if (status == NLMSG_ERROR) {
fprintf(stderr,
"ERROR packet_input: Check that the ip_queue.o module is loaded.\n");
die(h);
}
pkt = ipq_get_packet(buf);
#ifdef DEBUG_PACKET
DEBUG(LOG_DEBUG, 0, "Protocol %u indev=%s outdev=%s\n",
pkt->hw_protocol, pkt->indev_name, pkt->outdev_name);
#endif
if (pkt->hook == 0)
dev_name = pkt->indev_name;
else if (pkt->hook == 3)
dev_name = pkt->outdev_name;
else
dev_name = NULL;
/* We know from kaodv.c that this is an IP packet */
ip = (struct iphdr *) pkt->payload;
dest_addr = ntohl(ip->daddr);
src_addr = ntohl(ip->saddr);
switch (ip->protocol) {
/* Don't process AODV control packets (UDP on port 654). They
are accounted for on the aodv socket */
case IPPROTO_UDP:
udp = (struct udphdr *) ((char *) ip + (ip->ihl << 2));
if (ntohs(udp->dest) == AODV_PORT || ntohs(udp->source) == AODV_PORT)
goto accept;
break;
/* If this is a TCP packet and we don't have a route, we should
set the gratuituos flag in the RREQ. */
case IPPROTO_TCP:
rreq_flags |= RREQ_GRATUITOUS;
break;
/* We set the gratuitous flag also on ICMP ECHO requests, since
the destination will also need a route back for the reply... */
case IPPROTO_ICMP:
icmp = (struct icmphdr *) ((char *) ip + (ip->ihl << 2));
if (icmp->type == ICMP_ECHO)
rreq_flags |= RREQ_GRATUITOUS;
#ifdef DEBUG_PACKET
DEBUG(LOG_INFO, 0, "packet_input: setting G flag for RREQ to %s",
ip_to_str(dest_addr));
#endif
break;
default:
}
#ifdef DEBUG_PACKET
DEBUG(LOG_INFO, 0, "packet_input: pkt to %s", ip_to_str(dest_addr));
#endif
if (dev_name)
ifindex = if_nametoindex(dev_name);
else
ifindex = 0;
#endif /* NS_PORT */
/* If the packet is not interesting we just let it go through... */
if ((dest_addr == AODV_BROADCAST) ||
(dest_addr == DEV_IFINDEX(ifindex).ipaddr) ||
(dest_addr == DEV_IFINDEX(ifindex).broadcast) ||
((internet_gw_mode && this_host.gateway_mode)
&& ((dest_addr & DEV_IFINDEX(ifindex).netmask) !=
DEV_IFINDEX(ifindex).broadcast)))
goto accept;
/* Find the entry of the neighboring node and the destination (if any). */
rev_rt = rt_table_find_active(src_addr);
fwd_rt = rt_table_find_active(dest_addr);
/* If a packet is received on the NF_IP_PRE_ROUTING hook,
i.e. inbound on the interface and we don't have a route to the
destination, we should send an RERR to the source and then drop
the package... */
/* NF_IP_PRE_ROUTING = 0 */
#ifdef NS_PORT
#define PACKET_IS_INBOUND ch->direction() == hdr_cmn::UP
#else
#define PACKET_IS_INBOUND pkt->hook == 0
#endif
if ((dest_addr != DEV_IFINDEX(ifindex).ipaddr) &&
(!fwd_rt && PACKET_IS_INBOUND)) {
rt_table_t *rt_entry;
u_int32_t rerr_dest;
RERR *rerr;
DEBUG(LOG_DEBUG, 0, "packet_input: Sending RERR for unknown dest %s",
ip_to_str(dest_addr));
/* There is an expired entry in the routing table we want to send
along the seqno in the RERR... */
rt_entry = rt_table_find(dest_addr);
if (rt_entry) {
rerr = rerr_create(0, rt_entry->dest_addr, rt_entry->dest_seqno);
rt_table_update_timeout(rt_entry, DELETE_PERIOD);
} else
rerr = rerr_create(0, dest_addr, 0);
/* Unicast the RERR to the source of the data transmission if
* possible, otherwise we broadcast it. */
if (rev_rt)
rerr_dest = rev_rt->next_hop;
else
rerr_dest = AODV_BROADCAST;
aodv_socket_send((AODV_msg *) rerr, rerr_dest,
RERR_CALC_SIZE(rerr), 1, &DEV_IFINDEX(ifindex));
if (wait_on_reboot) {
DEBUG(LOG_DEBUG, 0, "packet_input: Wait on reboot timer reset.");
timer_add_msec(&worb_timer, DELETE_PERIOD);
}
#ifdef NS_PORT
drop(p, DROP_RTR_NO_ROUTE);
#else
status = ipq_set_verdict(h, pkt->packet_id, NF_DROP, 0, NULL);
if (status < 0)
die(h);
#endif
return;
}
/* Check if the route is currently in repair. In that case just
buffer the packet */
repair_rt = rt_table_find(dest_addr);
if (repair_rt && (repair_rt->flags & LREPAIR)) {
#ifdef NS_PORT
packet_queue_add(p, dest_addr);
#else
packet_queue_add(pkt->packet_id, dest_addr);
#endif
return;
}
/* update_timers: */
/* When forwarding a packet, we update the lifetime of the
destination's routing table entry, as well as the entry for the
next hop neighbor (if not the same). AODV draft 10, section
6.2. */
if (fwd_rt && dest_addr != DEV_IFINDEX(ifindex).ipaddr) {
rt_table_update_timeout(fwd_rt, ACTIVE_ROUTE_TIMEOUT);
next_hop_rt = rt_table_find_active(fwd_rt->next_hop);
if (next_hop_rt && next_hop_rt->dest_addr != fwd_rt->dest_addr)
rt_table_update_timeout(next_hop_rt, ACTIVE_ROUTE_TIMEOUT);
}
/* Also update the reverse route and reverse next hop along the
path back, since routes between originators and the destination
are expected to be symmetric. */
if (rev_rt) {
rt_table_update_timeout(rev_rt, ACTIVE_ROUTE_TIMEOUT);
next_hop_rt = rt_table_find_active(rev_rt->next_hop);
if (next_hop_rt && next_hop_rt->dest_addr != fwd_rt->dest_addr)
rt_table_update_timeout(next_hop_rt, ACTIVE_ROUTE_TIMEOUT);
}
#ifdef DEBUG_PACKET
DEBUG(LOG_INFO, 0, "packet_input: d=%s s=%s",
ip_to_str(dest_addr), ip_to_str(src_addr));
#endif /* DEBUG_PACKET */
if (!fwd_rt || (fwd_rt->hcnt == 1 && (fwd_rt->flags & UNIDIR))) {
/* Buffer packets... Packets are queued by the ip_queue_aodv.o module
already. We only need to save the handle id, and return the proper
verdict when we know what to do... */
#ifdef NS_PORT
packet_queue_add(p, dest_addr);
#else
packet_queue_add(pkt->packet_id, dest_addr);
/* If the request is generated locally by an application, we save
the IP header + 64 bits of data for sending an ICMP Destination
Host Unreachable in case we don't find a route... */
if (src_addr == DEV_IFINDEX(ifindex).ipaddr) {
ipd = (struct ip_data *) malloc(sizeof(struct ip_data));
if (ipd < 0) {
perror("Malloc for IP data failed!");
exit(-1);
}
ipd->len = (ip->ihl << 2) + 8; /* IP header + 64 bits data (8 bytes) */
memcpy(ipd->data, ip, ipd->len);
} else
ipd = NULL;
#endif
rreq_route_discovery(dest_addr, rreq_flags, ipd);
return;
}
accept:
#ifdef NS_PORT
if (fwd_rt)
sendPacket(p, fwd_rt->next_hop, 0.0);
else
drop(p, DROP_RTR_NO_ROUTE);
#else
status = ipq_set_verdict(h, pkt->packet_id, NF_ACCEPT, 0, NULL);
if (status < 0)
die(h);
#endif
return;
}
