serval-dna/overlay_interface.c
Andrew Bettison 259b9a9d24 Logging/debug improvements: __WHENCE__, __whence
Introduce __WHENCE__ macro and a block comment in log.h explaining it.

In "primitive" kinds of functions, rename 'whence' arguments to '__whence' and
use WHYF(), WARNF(), DEBUGF() macros instead of calling logMessage() directly.
2012-10-16 17:00:03 +10:30

1330 lines
41 KiB
C

/*
Serval Distributed Numbering Architecture (DNA)
Copyright (C) 2010 Paul Gardner-Stephen
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <assert.h>
#include <time.h>
#include "serval.h"
#include "strbuf.h"
#include "overlay_buffer.h"
#include "overlay_packet.h"
#ifdef HAVE_IFADDRS_H
#include <ifaddrs.h>
#endif
int overlay_ready=0;
int overlay_interface_count=0;
overlay_interface overlay_interfaces[OVERLAY_MAX_INTERFACES];
int overlay_last_interface_number=-1;
struct interface_rules {
char *namespec;
unsigned long long speed_in_bits;
int port;
char type;
char excludeP;
struct interface_rules *next;
};
struct interface_rules *interface_filter=NULL;
struct profile_total interface_poll_stats;
struct profile_total dummy_poll_stats;
struct sched_ent sock_any;
struct sockaddr_in sock_any_addr;
struct profile_total sock_any_stats;
struct outgoing_packet{
overlay_interface *interface;
int i;
int unicast;
struct sockaddr_in dest;
struct overlay_buffer *buffer;
};
struct sched_ent next_packet;
struct profile_total send_packet;
static int overlay_tick_interface(int i, time_ms_t now);
static void overlay_interface_poll(struct sched_ent *alarm);
static void logServalPacket(int level, struct __sourceloc __whence, const char *message, const unsigned char *packet, size_t len);
static long long parse_quantity(char *q);
#define DEBUG_packet_visualise(M,P,N) logServalPacket(LOG_LEVEL_DEBUG, __WHENCE__, (M), (P), (N))
unsigned char magic_header[]={/* Magic */ 'O',0x10,
/* Version */ 0x00,0x01};
static int overlay_interface_type(char *s)
{
if (!strcasecmp(s,"ethernet")) return OVERLAY_INTERFACE_ETHERNET;
if (!strcasecmp(s,"wifi")) return OVERLAY_INTERFACE_WIFI;
if (!strcasecmp(s,"other")) return OVERLAY_INTERFACE_UNKNOWN;
if (!strcasecmp(s,"catear")) return OVERLAY_INTERFACE_PACKETRADIO;
return WHY("Invalid interface type -- consider using 'wifi','ethernet' or 'other'");
}
int overlay_interface_arg(char *arg)
{
/* Parse an interface argument, of the form:
<+|->[interfacename][=type]
+interface tells DNA to sit on that interface
-interface tells DNA to not sit on that interface
+/- without an interface tells DNA to sit on all interfaces.
The first match rules, so -en0+ tells DNA to use all interfaces, excepting en0
The optional =type specifier tells DNA how to handle the interface in terms of
bandwidth:distance relationship for calculating tick times etc.
The special type =custom allows full specification:
XXX - Settle the custom specification now that we have changed the interface
management.
*/
char sign[80]="+";
char interface_name[80]="";
char speed[80]="1m";
char typestring[80]="wifi";
int port=PORT_DNA;
int type=OVERLAY_INTERFACE_UNKNOWN;
int n=0;
/* Too long */
if (strlen(arg)>79) return WHY("interface specification was >79 characters");
struct interface_rules *r=calloc(sizeof(struct interface_rules),1);
if (!r) return WHY("calloc(struct interface rules),1) failed");
if (sscanf(arg,"%[+-]%n%[^=:,]%n=%[^:]%n:%d%n:%[^:]%n",
sign,&n,interface_name,&n,typestring,&n,&port,&n,speed,&n)>=1)
{
if (n<strlen(arg)) { free(r); return WHY("Extra junk at end of interface specification"); }
if (strlen(sign)>1) { free(r); return WHY("Sign must be + or -"); }
switch(sign[0])
{
case '+': break;
case '-': r->excludeP=1; break;
default:
free(r);
return WHY("Invalid interface list item: Must begin with + or -");
}
long long speed_in_bits=parse_quantity(speed);
if (speed_in_bits<=1) {
free(r);
return WHY("Interfaces must be capable of at least 1 bit per second");
}
if (n<strlen(arg)) return WHY("Extra stuff at end of interface specification");
type=overlay_interface_type(typestring);
if (type<0) { free(r); return WHY("Invalid interface type in specification"); }
/* Okay, register the interface preference */
r->namespec=strdup(interface_name);
r->speed_in_bits=speed_in_bits;
r->port=port;
r->type=type;
r->next=interface_filter;
interface_filter=r;
return 0;
}
else { free(r); return WHY("Bad interface specification"); }
}
int overlay_interface_args(const char *arg)
{
/* Parse series of comma-separated interface definitions from a single argument
*/
int i=0;
char interface[80];
int len=0;
for(i=0;arg[i];i++)
{
if (arg[i]==','||arg[i]=='\n') {
interface[len]=0;
if (overlay_interface_arg(interface)) return WHY("Could not add interface");
len=0;
} else {
if (len<79) {
interface[len++]=arg[i];
interface[len]=0;
} else
return WHY("Interface definition is too long (each must be <80 characters)");
}
}
if (len) if (overlay_interface_arg(interface)) return WHY("Could not add final interface");
return 0;
}
static void
overlay_interface_close(overlay_interface *interface){
if (interface->fileP){
INFOF("Interface %s is down", interface->name);
}else{
INFOF("Interface %s addr %s is down", interface->name, inet_ntoa(interface->broadcast_address.sin_addr));
}
unschedule(&interface->alarm);
unwatch(&interface->alarm);
close(interface->alarm.poll.fd);
interface->alarm.poll.fd=-1;
interface->state=INTERFACE_STATE_DOWN;
}
// create a socket with options common to all our UDP sockets
static int
overlay_bind_socket(const struct sockaddr *addr, size_t addr_size, char *interface_name){
int fd;
int reuseP = 1;
int broadcastP = 1;
fd = socket(PF_INET,SOCK_DGRAM,0);
if (fd < 0) {
WHY_perror("Error creating socket");
return -1;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &reuseP, sizeof(reuseP)) < 0) {
WHY_perror("setsockopt(SO_REUSEADR)");
goto error;
}
#ifdef SO_REUSEPORT
if (setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &reuseP, sizeof(reuseP)) < 0) {
WHY_perror("setsockopt(SO_REUSEPORT)");
goto error;
}
#endif
if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &broadcastP, sizeof(broadcastP)) < 0) {
WHY_perror("setsockopt(SO_BROADCAST)");
goto error;
}
/* Automatically close socket on calls to exec().
This makes life easier when we restart with an exec after receiving
a bad signal. */
fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, NULL) |
#ifdef FD_CLOEXEC
FD_CLOEXEC
#else
O_CLOEXEC
#endif
);
#ifdef SO_BINDTODEVICE
/*
Limit incoming and outgoing packets to this interface, no matter what the routing table says.
This should allow for a device with multiple interfaces on the same subnet.
Don't abort if this fails, I believe it requires root, just log it.
*/
if (interface_name && setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, interface_name, strlen(interface_name)+1) < 0) {
WHY_perror("setsockopt(SO_BINDTODEVICE)");
}
#endif
if (bind(fd, addr, addr_size)) {
WHY_perror("Bind failed");
goto error;
}
return fd;
error:
close(fd);
return -1;
}
overlay_interface * overlay_interface_find(struct in_addr addr){
int i;
for (i=0;i<OVERLAY_MAX_INTERFACES;i++){
if (overlay_interfaces[i].state!=INTERFACE_STATE_UP)
continue;
if ((overlay_interfaces[i].netmask.s_addr & addr.s_addr) == (overlay_interfaces[i].netmask.s_addr & overlay_interfaces[i].address.sin_addr.s_addr)){
return &overlay_interfaces[i];
}
}
return NULL;
}
overlay_interface * overlay_interface_find_name(const char *name){
int i;
for (i=0;i<OVERLAY_MAX_INTERFACES;i++){
if (overlay_interfaces[i].state!=INTERFACE_STATE_UP)
continue;
if (strcasecmp((*name=='>'?name+1:name),
(*overlay_interfaces[i].name=='>'?overlay_interfaces[i].name+1:overlay_interfaces[i].name)
)==0){
return &overlay_interfaces[i];
}
}
return NULL;
}
// OSX doesn't recieve broadcast packets on sockets bound to an interface's address
// So we have to bind a socket to INADDR_ANY to receive these packets.
static void
overlay_interface_read_any(struct sched_ent *alarm){
if (alarm->poll.revents & POLLIN) {
int plen=0;
int recvttl=1;
unsigned char packet[16384];
overlay_interface *interface=NULL;
struct sockaddr src_addr;
socklen_t addrlen = sizeof(src_addr);
/* Read only one UDP packet per call to share resources more fairly, and also
enable stats to accurately count packets received */
plen = recvwithttl(alarm->poll.fd, packet, sizeof(packet), &recvttl, &src_addr, &addrlen);
if (plen == -1) {
WHY_perror("recvwithttl(c)");
unwatch(alarm);
close(alarm->poll.fd);
return;
}
struct in_addr src = ((struct sockaddr_in *)&src_addr)->sin_addr;
/* Try to identify the real interface that the packet arrived on */
interface = overlay_interface_find(src);
/* Drop the packet if we don't find a match */
if (!interface){
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Could not find matching interface for packet received from %s", inet_ntoa(src));
return;
}
/* We have a frame from this interface */
if (debug&DEBUG_PACKETRX)
DEBUG_packet_visualise("Read from real interface", packet,plen);
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Received %d bytes from %s on interface %s (ANY)",plen,
inet_ntoa(((struct sockaddr_in *)&src_addr)->sin_addr),
interface->name);
if (packetOk(interface,packet,plen,NULL,recvttl,&src_addr,addrlen,1)) {
WHY("Malformed packet");
}
}
if (alarm->poll.revents & (POLLHUP | POLLERR)) {
INFO("Closing broadcast socket due to error");
unwatch(alarm);
close(alarm->poll.fd);
alarm->poll.fd=-1;
}
}
// bind a socket to INADDR_ANY:port
// for now, we don't have a graceful close for this interface but it should go away when the process dies
static int overlay_interface_init_any(int port){
struct sockaddr_in addr;
if (sock_any.poll.fd>0){
// Check the port number matches
if (sock_any_addr.sin_port != htons(port))
return WHYF("Unable to listen to broadcast packets for ports %d & %d", port, ntohs(sock_any_addr.sin_port));
return 0;
}
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = INADDR_ANY;
sock_any.poll.fd = overlay_bind_socket((const struct sockaddr *)&addr, sizeof(addr), NULL);
if (sock_any.poll.fd<0)
return -1;
sock_any_addr = addr;
sock_any.poll.events=POLLIN;
sock_any.function = overlay_interface_read_any;
sock_any_stats.name="overlay_interface_read_any";
sock_any.stats=&sock_any_stats;
watch(&sock_any);
return 0;
}
static int
overlay_interface_init_socket(int interface_index)
{
overlay_interface *const interface = &overlay_interfaces[interface_index];
interface->fileP = 0;
/*
On linux you can bind to the broadcast address to receive broadcast packets per interface [or subnet],
but then you can't receive unicast packets on the same socket.
On osx, you can only receive broadcast packets if you bind to INADDR_ANY.
So the most portable way to do this is to bind to each interface's IP address for sending broadcasts
and receiving unicasts, and bind a separate socket to INADDR_ANY just for receiving broadcast packets.
Sending packets from INADDR_ANY would probably work, but gives us less control over which interfaces are sending packets.
But there may be some platforms that need some other combination for everything to work.
*/
overlay_interface_init_any(interface->port);
const struct sockaddr *addr = (const struct sockaddr *)&interface->address;
interface->alarm.poll.fd = overlay_bind_socket(addr, sizeof(interface->broadcast_address), interface->name);
if (interface->alarm.poll.fd<0){
interface->state=INTERFACE_STATE_DOWN;
return -1;
}
if (debug & (DEBUG_PACKETRX | DEBUG_IO)){
char srctxt[INET_ADDRSTRLEN];
if (inet_ntop(AF_INET, (const void *)&interface->broadcast_address.sin_addr, srctxt, INET_ADDRSTRLEN))
DEBUGF("Bound to %s:%d", srctxt, ntohs(interface->broadcast_address.sin_port));
}
interface->alarm.poll.events=POLLIN;
interface->alarm.function = overlay_interface_poll;
interface_poll_stats.name="overlay_interface_poll";
interface->alarm.stats=&interface_poll_stats;
watch(&interface->alarm);
if (interface->tick_ms>0){
// run the first tick asap
interface->alarm.alarm=gettime_ms();
interface->alarm.deadline=interface->alarm.alarm+10;
schedule(&interface->alarm);
}
interface->state=INTERFACE_STATE_UP;
INFOF("Interface %s addr %s, is up",interface->name, inet_ntoa(interface->broadcast_address.sin_addr));
// mark our sid to be sent in full
if (my_subscriber)
my_subscriber->send_full = 1;
directory_registration();
return 0;
}
static int
overlay_interface_init(char *name, struct in_addr src_addr, struct in_addr netmask,
struct in_addr broadcast,
int speed_in_bits, int port, int type)
{
/* Too many interfaces */
if (overlay_interface_count>=OVERLAY_MAX_INTERFACES) return WHY("Too many interfaces -- Increase OVERLAY_MAX_INTERFACES");
overlay_interface *const interface = &overlay_interfaces[overlay_interface_count];
strcpy(interface->name,name);
/* Pick a reasonable default MTU.
This will ultimately get tuned by the bandwidth and other properties of the interface */
interface->mtu=1200;
interface->state=INTERFACE_STATE_DOWN;
interface->bits_per_second=speed_in_bits;
interface->port=port;
interface->type=type;
interface->last_tick_ms= -1; // not ticked yet
interface->alarm.poll.fd=0;
// how often do we announce ourselves on this interface?
switch (type) {
case OVERLAY_INTERFACE_PACKETRADIO:
interface->tick_ms = confValueGetInt64Range("mdp.packetradio.tick_ms", 15000LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_ETHERNET:
interface->tick_ms = confValueGetInt64Range("mdp.ethernet.tick_ms", 500LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_WIFI:
interface->tick_ms = confValueGetInt64Range("mdp.wifi.tick_ms", 500LL, 1LL, 3600000LL);
break;
case OVERLAY_INTERFACE_UNKNOWN:
interface->tick_ms = confValueGetInt64Range("mdp.unknown.tick_ms", 500LL, 1LL, 3600000LL);
break;
default:
return WHYF("Unsupported interface type %d", type);
}
// allow for a per interface override of tick interval
{
char option_name[64];
snprintf(option_name, sizeof(option_name), "mdp.%s.tick_ms", (*name=='>'?name+1:name));
interface->tick_ms = confValueGetInt64Range(option_name, interface->tick_ms, 1LL, 3600000LL);
}
// disable announcements and other broadcasts if tick_ms=0.
if (interface->tick_ms>0)
interface->send_broadcasts=1;
else{
interface->send_broadcasts=0;
INFOF("Interface %s is running tickless", name);
}
if (name[0]=='>') {
interface->fileP=1;
char dummyfile[1024];
if (name[1]=='/') {
/* Absolute path */
snprintf(dummyfile, sizeof(dummyfile), "%s", &name[1]);
} else {
const char *interface_folder = confValueGet("interface.folder", serval_instancepath());
snprintf(dummyfile, sizeof(dummyfile), "%s/%s", interface_folder, &name[1]);
}
if ((interface->alarm.poll.fd = open(dummyfile,O_APPEND|O_RDWR)) < 1) {
return WHYF("could not open dummy interface file %s for append", dummyfile);
}
/* Seek to end of file as initial reading point */
interface->recv_offset = lseek(interface->alarm.poll.fd,0,SEEK_END);
/* XXX later add pretend location information so that we can decide which "packets" to receive
based on closeness */
// schedule an alarm for this interface
interface->alarm.function=overlay_dummy_poll;
interface->alarm.alarm=gettime_ms()+10;
interface->alarm.deadline=interface->alarm.alarm;
dummy_poll_stats.name="overlay_dummy_poll";
interface->alarm.stats=&dummy_poll_stats;
schedule(&interface->alarm);
interface->state=INTERFACE_STATE_UP;
INFOF("Dummy interface %s is up",interface->name);
// mark our sid to be sent in full
if (my_subscriber)
my_subscriber->send_full = 1;
directory_registration();
} else {
interface->netmask = netmask;
interface->address.sin_addr = src_addr;
interface->address.sin_family = AF_INET;
interface->address.sin_port = htons(interface->port);
interface->broadcast_address.sin_addr = broadcast;
interface->broadcast_address.sin_family = AF_INET;
interface->broadcast_address.sin_port = htons(interface->port);
if (overlay_interface_init_socket(overlay_interface_count))
return WHY("overlay_interface_init_socket() failed");
}
overlay_interface_count++;
return 0;
}
static void overlay_interface_poll(struct sched_ent *alarm)
{
struct overlay_interface *interface = (overlay_interface *)alarm;
if (alarm->poll.revents==0){
if (interface->state==INTERFACE_STATE_UP && interface->tick_ms>0){
// tick the interface
time_ms_t now = gettime_ms();
int i = (interface - overlay_interfaces);
overlay_tick_interface(i, now);
alarm->alarm=now+interface->tick_ms;
alarm->deadline=alarm->alarm+interface->tick_ms/2;
schedule(alarm);
}
return;
}
if (alarm->poll.revents & POLLIN) {
int plen=0;
unsigned char packet[16384];
struct sockaddr src_addr;
socklen_t addrlen = sizeof(src_addr);
/* Read only one UDP packet per call to share resources more fairly, and also
enable stats to accurately count packets received */
int recvttl=1;
plen = recvwithttl(alarm->poll.fd,packet, sizeof(packet), &recvttl, &src_addr, &addrlen);
if (plen == -1) {
WHY_perror("recvwithttl(c)");
overlay_interface_close(interface);
return;
}
/* We have a frame from this interface */
if (debug&DEBUG_PACKETRX)
DEBUG_packet_visualise("Read from real interface", packet,plen);
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Received %d bytes from %s on interface %s",plen,
inet_ntoa(((struct sockaddr_in *)&src_addr)->sin_addr),
interface->name);
if (packetOk(interface,packet,plen,NULL,recvttl,&src_addr,addrlen,1)) {
WHY("Malformed packet");
// Do we really want to attempt to parse it again?
//DEBUG_packet_visualise("Malformed packet", packet,plen);
}
}
if (alarm->poll.revents & (POLLHUP | POLLERR)) {
overlay_interface_close(interface);
}
}
void overlay_dummy_poll(struct sched_ent *alarm)
{
overlay_interface *interface = (overlay_interface *)alarm;
/* Grab packets, unpackage and dispatch frames to consumers */
/* XXX Okay, so how are we managing out-of-process consumers?
They need some way to register their interest in listening to a port.
*/
unsigned char packet[2048];
int plen=0;
struct sockaddr src_addr;
size_t addrlen = sizeof(src_addr);
unsigned char transaction_id[8];
time_ms_t now = gettime_ms();
/* Read from dummy interface file */
long long length=lseek(alarm->poll.fd,0,SEEK_END);
int new_packets = (length - interface->recv_offset) / sizeof packet;
if (new_packets > 20)
WARNF("Getting behind, there are %d unread packets", new_packets);
if (interface->recv_offset >= length) {
/* if there's no input, while we want to check for more soon,
we need to allow all other low priority alarms to fire first,
otherwise we'll dominate the scheduler without accomplishing anything */
alarm->alarm = gettime_ms() + 5;
if (interface->last_tick_ms != -1 && alarm->alarm > interface->last_tick_ms + interface->tick_ms)
alarm->alarm = interface->last_tick_ms + interface->tick_ms;
alarm->deadline = alarm->alarm + 10000;
} else {
if (lseek(alarm->poll.fd,interface->recv_offset,SEEK_SET) == -1)
WHY_perror("lseek");
else {
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Read interface %s (size=%lld) at offset=%d",interface->name, length, interface->recv_offset);
ssize_t nread = read(alarm->poll.fd, packet, sizeof packet);
if (nread == -1)
WHY_perror("read");
else {
if (nread == sizeof packet) {
interface->recv_offset += nread;
plen = packet[110] + (packet[111] << 8);
if (plen > nread - 128)
plen = -1;
if (debug&DEBUG_PACKETRX)
DEBUG_packet_visualise("Read from dummy interface", &packet[128], plen);
bzero(&transaction_id[0],8);
bzero(&src_addr,sizeof(src_addr));
if (plen >= 4) {
if (packet[0] == 0x01 && packet[1] == 0 && packet[2] == 0 && packet[3] == 0) {
if (packetOk(interface,&packet[128],plen,transaction_id, -1 /* fake TTL */, &src_addr,addrlen,1) == -1)
WARN("Unsupported packet from dummy interface");
} else {
WARNF("Unsupported packet version from dummy interface: %02x %02x %02x %02x", packet[0], packet[1], packet[2], packet[3]);
}
} else {
WARNF("Invalid packet from dummy interface: plen=%lld", (long long) plen);
}
}
else
WARNF("Read %lld bytes from dummy interface", nread);
}
}
/* keep reading new packets as fast as possible,
but don't completely prevent other high priority alarms */
if (interface->recv_offset >= length)
alarm->alarm = gettime_ms() + 5;
else
alarm->alarm = gettime_ms();
alarm->deadline = alarm->alarm + 100;
}
// only tick the interface if we've caught up reading all the packets
if (interface->recv_offset >= length &&
interface->tick_ms>0 &&
(interface->last_tick_ms == -1 || now >= interface->last_tick_ms + interface->tick_ms)) {
// tick the interface
int i = (interface - overlay_interfaces);
overlay_tick_interface(i, now);
}
schedule(alarm);
return ;
}
static int
overlay_broadcast_ensemble(int interface_number,
struct sockaddr_in *recipientaddr,
unsigned char *bytes,int len)
{
if (debug&DEBUG_PACKETTX)
{
DEBUGF("Sending this packet via interface #%d",interface_number);
DEBUG_packet_visualise(NULL,bytes,len);
}
overlay_interface *interface = &overlay_interfaces[interface_number];
if (interface->state!=INTERFACE_STATE_UP){
return WHYF("Cannot send to interface %s as it is down", interface->name);
}
if (interface->fileP)
{
char buf[2048];
bzero(&buf[0],128);
/* Version information */
buf[0]=1; buf[1]=0;
buf[2]=0; buf[3]=0;
/* PID of creator */
buf[4]=getpid()&0xff; buf[5]=getpid()>>8;
/* TODO make a structure for all this stuff */
/* bytes 4-5 = half-power beam height (uint16) */
/* bytes 6-7 = half-power beam width (uint16) */
/* bytes 8-11 = range in metres, centre beam (uint32) */
/* bytes 16-47 = sender */
/* bytes 48-79 = next hop */
/* bytes 80-83 = latitude (uint32) */
/* bytes 84-87 = longitude (uint32) */
/* bytes 88-89 = X/Z direction (uint16) */
/* bytes 90-91 = Y direction (uint16) */
/* bytes 92-93 = speed in metres per second (uint16) */
/* bytes 94-97 = TX frequency in Hz, uncorrected for doppler (which must be done at the receiving end to take into account
relative motion) */
/* bytes 98-109 = coding method (use for doppler response etc) null terminated string */
/* bytes 110-111 = length of packet body in bytes */
/* bytes 112-127 reserved for future use */
if (len>2048-128) {
WARN("Truncating long packet to fit within 1920 byte limit for dummy interface");
len=2048-128;
}
/* Record length of packet */
buf[110]=len&0xff;
buf[111]=(len>>8)&0xff;
bzero(&buf[128+len],2048-(128+len));
bcopy(bytes,&buf[128],len);
/* This lseek() is unneccessary because the dummy file is opened in O_APPEND mode. It's
only purpose is to find out the offset to print in the DEBUG statement. It is vulnerable
to a race condition with other processes appending to the same file. */
off_t fsize = lseek(interface->alarm.poll.fd, (off_t) 0, SEEK_END);
if (fsize == -1)
return WHY_perror("lseek");
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Write to interface %s at offset=%d", interface->name, fsize);
ssize_t nwrite = write(interface->alarm.poll.fd, buf, 2048);
if (nwrite == -1)
return WHY_perror("write");
if (nwrite != 2048)
return WHYF("only wrote %lld of %lld bytes", nwrite, 2048);
return 0;
}
else
{
if (debug&DEBUG_OVERLAYINTERFACES)
DEBUGF("Sending %d byte overlay frame on %s to %s",len,interface->name,inet_ntoa(recipientaddr->sin_addr));
if(sendto(interface->alarm.poll.fd,
bytes, len, 0, (struct sockaddr *)recipientaddr, sizeof(struct sockaddr_in)) != len){
WHY_perror("sendto(c)");
overlay_interface_close(interface);
return -1;
}
return 0;
}
}
/* This function is called to return old non-overlay requests back out the
interface they came in. */
int overlay_sendto(struct sockaddr_in *recipientaddr,unsigned char *bytes,int len)
{
if (debug&DEBUG_PACKETTX) DEBUGF("Sending %d bytes",len);
if (overlay_broadcast_ensemble(overlay_last_interface_number,recipientaddr,bytes,len) == -1)
return -1;
return len;
}
/* Register the interface, or update the existing interface registration */
int
overlay_interface_register(char *name,
struct in_addr addr,
struct in_addr mask) {
struct interface_rules *r, *me;
int i;
struct in_addr broadcast = {.s_addr = addr.s_addr | ~mask.s_addr};
if (debug & DEBUG_OVERLAYINTERFACES) {
// note, inet_ntop doesn't seem to behave on android
DEBUGF("%s address: %s", name, inet_ntoa(addr));
DEBUGF("%s broadcast address: %s", name, inet_ntoa(broadcast));
}
/* See if the interface is listed in the filter */
me = NULL;
r = interface_filter;
while(r) {
if (!strcasecmp(name, r->namespec))
me = r;
r = r->next;
}
if (me == NULL || me->excludeP) {
if (debug & DEBUG_OVERLAYINTERFACES)
DEBUGF("Interface %s is not interesting.",name);
return 0;
}
int found_interface= -1;
/* Search in the exist list of interfaces */
for(i = 0; i < overlay_interface_count; i++){
int broadcast_match = 0;
int name_match =0;
if ((overlay_interfaces[i].broadcast_address.sin_addr.s_addr & 0xffffffff)
== (broadcast.s_addr & 0xffffffff)){
broadcast_match = 1;
}
name_match = !strcasecmp(overlay_interfaces[i].name, name);
// if we find an exact match we can stop searching
if (name_match && broadcast_match){
// mark this interface as still alive
if (overlay_interfaces[i].state==INTERFACE_STATE_DETECTING)
overlay_interfaces[i].state=INTERFACE_STATE_UP;
// try to bring the interface back up again even if the address has changed
if (overlay_interfaces[i].state==INTERFACE_STATE_DOWN){
overlay_interfaces[i].address.sin_addr = addr;
overlay_interface_init_socket(i);
}
// we already know about this interface, and it's up so stop looking immediately
return 0;
}
// remember this slot to bring the interface back up again, even if the address has changed
if (name_match && overlay_interfaces[i].state==INTERFACE_STATE_DOWN)
found_interface=i;
}
if (found_interface>=0){
// try to reactivate the existing interface
overlay_interfaces[found_interface].address.sin_addr = addr;
overlay_interfaces[found_interface].broadcast_address.sin_addr = broadcast;
overlay_interfaces[found_interface].netmask = mask;
return overlay_interface_init_socket(found_interface);
}
/* New interface, so register it */
if (overlay_interface_init(name, addr, mask, broadcast, me->speed_in_bits, me->port, me->type))
return WHYF("Could not initialise newly seen interface %s", name);
else
if (debug & DEBUG_OVERLAYINTERFACES) DEBUGF("Registered interface %s", name);
return 0;
}
void overlay_interface_discover(struct sched_ent *alarm){
int i;
struct interface_rules *r;
struct in_addr dummyaddr;
int detect_real_interfaces = 0;
/* Mark all UP interfaces as DETECTING, so we can tell which interfaces are new, and which are dead */
for (i = 0; i < overlay_interface_count; i++)
if (overlay_interfaces[i].state==INTERFACE_STATE_UP)
overlay_interfaces[i].state=INTERFACE_STATE_DETECTING;
/* Check through for any virtual dummy interfaces */
for (r = interface_filter; r != NULL; r = r->next) {
if (r->namespec[0] != '>'){
detect_real_interfaces = 1;
continue;
}
for (i = 0; i < overlay_interface_count; i++)
if (!strcasecmp(overlay_interfaces[i].name,r->namespec)){
if (overlay_interfaces[i].state==INTERFACE_STATE_DETECTING)
overlay_interfaces[i].state=INTERFACE_STATE_UP;
break;
}
if (i >= overlay_interface_count){
/* New interface, so register it */
overlay_interface_init(r->namespec,dummyaddr,dummyaddr,dummyaddr,1000000,PORT_DNA,OVERLAY_INTERFACE_WIFI);
}
}
/* Look for real interfaces */
if (detect_real_interfaces){
int no_route = 1;
#ifdef HAVE_IFADDRS_H
if (no_route != 0)
no_route = doifaddrs();
#endif
#ifdef SIOCGIFCONF
if (no_route != 0)
no_route = lsif();
#endif
#ifdef linux
if (no_route != 0)
no_route = scrapeProcNetRoute();
#endif
if (no_route != 0) {
FATAL("Unable to get any interface information");
}
}
// detect if any interfaces have gone away and need to be closed
for(i = 0; i < overlay_interface_count; i++)
if (overlay_interfaces[i].state==INTERFACE_STATE_DETECTING)
overlay_interface_close(&overlay_interfaces[i]);
alarm->alarm = gettime_ms()+5000;
alarm->deadline = alarm->alarm + 10000;
schedule(alarm);
return;
}
/* remove and free a payload from the queue */
static struct overlay_frame *
overlay_queue_remove(overlay_txqueue *queue, struct overlay_frame *frame){
struct overlay_frame *prev = frame->prev;
struct overlay_frame *next = frame->next;
if (prev)
prev->next = next;
else if(frame == queue->first)
queue->first = next;
if (next)
next->prev = prev;
else if(frame == queue->last)
queue->last = prev;
queue->length--;
op_free(frame);
return next;
}
#if 0 /* unused */
static int
overlay_queue_dump(overlay_txqueue *q)
{
strbuf b = strbuf_alloca(8192);
struct overlay_frame *f;
strbuf_sprintf(b,"overlay_txqueue @ 0x%p\n",q);
strbuf_sprintf(b," length=%d\n",q->length);
strbuf_sprintf(b," maxLenght=%d\n",q->maxLength);
strbuf_sprintf(b," latencyTarget=%d milli-seconds\n",q->latencyTarget);
strbuf_sprintf(b," first=%p\n",q->first);
f=q->first;
while(f) {
strbuf_sprintf(b," %p: ->next=%p, ->prev=%p\n",
f,f->next,f->prev);
if (f==f->next) {
strbuf_sprintf(b," LOOP!\n"); break;
}
f=f->next;
}
strbuf_sprintf(b," last=%p\n",q->last);
f=q->last;
while(f) {
strbuf_sprintf(b," %p: ->next=%p, ->prev=%p\n",
f,f->next,f->prev);
if (f==f->prev) {
strbuf_sprintf(b," LOOP!\n"); break;
}
f=f->prev;
}
DEBUG(strbuf_str(b));
return 0;
}
#endif // 0
static void
overlay_init_packet(struct outgoing_packet *packet, overlay_interface *interface, int tick){
packet->interface = interface;
packet->i = (interface - overlay_interfaces);
packet->dest=interface->broadcast_address;
packet->buffer=ob_new();
ob_limitsize(packet->buffer, packet->interface->mtu);
ob_append_bytes(packet->buffer,magic_header,4);
overlay_address_clear();
if (tick){
/* 1. Send announcement about ourselves, including one SID that we host if we host more than one SID
(the first SID we host becomes our own identity, saving a little bit of data here).
*/
overlay_add_selfannouncement(packet->i, packet->buffer);
}else{
// add a badly formatted dummy self announce payload to tell people we sent this.
ob_append_byte(packet->buffer, OF_TYPE_SELFANNOUNCE);
ob_append_byte(packet->buffer, 1);
ob_append_rfs(packet->buffer, SID_SIZE + 2);
/* from me, to me, via me
(it's shorter than an actual broadcast,
and receivers wont try to process it
since its not going to have a payload body anyway) */
overlay_address_append_self(interface, packet->buffer);
overlay_address_set_sender(my_subscriber);
ob_append_byte(packet->buffer, OA_CODE_PREVIOUS);
ob_append_byte(packet->buffer, OA_CODE_PREVIOUS);
ob_patch_rfs(packet->buffer, COMPUTE_RFS_LENGTH);
}
}
// update the alarm time and return 1 if changed
static int
overlay_calc_queue_time(overlay_txqueue *queue, struct overlay_frame *frame){
int ret=0;
time_ms_t send_time;
// ignore packet if the destination is currently unreachable
if (frame->destination && subscriber_is_reachable(frame->destination)==REACHABLE_NONE)
return 0;
// when is the next packet from this queue due?
send_time=queue->first->enqueued_at + queue->transmit_delay;
if (next_packet.alarm==0 || send_time < next_packet.alarm){
next_packet.alarm=send_time;
ret = 1;
}
// how long can we wait if the server is busy?
send_time += queue->grace_period;
if (next_packet.deadline==0 || send_time < next_packet.deadline){
next_packet.deadline=send_time;
ret = 1;
}
if (!next_packet.function){
next_packet.function=overlay_send_packet;
send_packet.name="overlay_send_packet";
next_packet.stats=&send_packet;
}
return ret;
}
static void
overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, time_ms_t now){
struct overlay_frame *frame = queue->first;
// TODO stop when the packet is nearly full?
while(frame){
if (frame->enqueued_at + queue->latencyTarget < now){
DEBUGF("Dropping frame type %x for %s due to expiry timeout",
frame->type, frame->destination?alloca_tohex_sid(frame->destination->sid):"All");
frame = overlay_queue_remove(queue, frame);
continue;
}
/* Note, once we queue a broadcast packet we are committed to sending it out every interface,
even if we hear it from somewhere else in the mean time
*/
struct subscriber *next_hop = frame->destination;
if (next_hop){
switch(subscriber_is_reachable(next_hop)){
case REACHABLE_NONE:
goto skip;
case REACHABLE_INDIRECT:
next_hop=next_hop->next_hop;
frame->sendBroadcast=0;
break;
case REACHABLE_DEFAULT_ROUTE:
next_hop=directory_service;
frame->sendBroadcast=0;
break;
case REACHABLE_DIRECT:
case REACHABLE_UNICAST:
frame->sendBroadcast=0;
break;
case REACHABLE_BROADCAST:
if (!frame->sendBroadcast){
if (frame->ttl>2)
frame->ttl=2;
frame->sendBroadcast=1;
if (is_all_matching(frame->broadcast_id.id, BROADCAST_LEN, 0)){
overlay_broadcast_generate_address(&frame->broadcast_id);
// mark it as already seen so we don't immediately retransmit it
overlay_broadcast_drop_check(&frame->broadcast_id);
}
int i;
for(i=0;i<OVERLAY_MAX_INTERFACES;i++)
frame->broadcast_sent_via[i]=0;
}
break;
}
}
if (!packet->buffer){
// use the interface of the first payload we find
if (frame->sendBroadcast){
// find an interface that we haven't broadcast on yet
int i;
for(i=0;i<OVERLAY_MAX_INTERFACES;i++)
{
if (overlay_interfaces[i].state==INTERFACE_STATE_UP
&& !frame->broadcast_sent_via[i]){
overlay_init_packet(packet, &overlay_interfaces[i], 0);
break;
}
}
if (!packet->buffer){
// oh dear, why is this broadcast still in the queue?
frame = overlay_queue_remove(queue, frame);
continue;
}
}else{
overlay_init_packet(packet, next_hop->interface, 0);
if (next_hop->reachable==REACHABLE_UNICAST){
packet->dest = next_hop->address;
packet->unicast=1;
}
}
}else{
// make sure this payload can be sent via this interface
if (frame->sendBroadcast){
if (frame->broadcast_sent_via[packet->i]){
goto skip;
}
}else{
if(packet->interface != next_hop->interface)
goto skip;
if (next_hop->reachable==REACHABLE_DIRECT && packet->unicast)
goto skip;
if (next_hop->reachable==REACHABLE_UNICAST &&
((!packet->unicast) ||
packet->dest.sin_addr.s_addr != next_hop->address.sin_addr.s_addr))
goto skip;
}
}
if (debug&DEBUG_OVERLAYFRAMES){
DEBUGF("Sending payload type %x len %d for %s via %s", frame->type, frame->payload->position,
frame->destination?alloca_tohex_sid(frame->destination->sid):"All",
frame->sendBroadcast?alloca_tohex(frame->broadcast_id.id, BROADCAST_LEN):alloca_tohex_sid(next_hop->sid));
}
if (overlay_frame_append_payload(packet->interface, frame, next_hop, packet->buffer))
// payload was not queued
goto skip;
// mark the payload as sent
int keep_payload = 0;
if (frame->sendBroadcast){
int i;
frame->broadcast_sent_via[packet->i]=1;
// check if there is still a broadcast to be sent
for(i=0;i<OVERLAY_MAX_INTERFACES;i++)
{
if (overlay_interfaces[i].state==INTERFACE_STATE_UP)
if (!frame->broadcast_sent_via[i]){
keep_payload=1;
break;
}
}
}else{
frame->send_copies --;
if (frame->send_copies>0)
keep_payload=1;
}
if (!keep_payload){
frame = overlay_queue_remove(queue, frame);
continue;
}
skip:
// if we can't send the payload now, check when we should try
overlay_calc_queue_time(queue, frame);
frame = frame->next;
}
}
// fill a packet from our outgoing queues and send it
static int
overlay_fill_send_packet(struct outgoing_packet *packet, time_ms_t now) {
int i;
IN();
// while we're looking at queues, work out when to schedule another packet
unschedule(&next_packet);
next_packet.alarm=0;
next_packet.deadline=0;
for (i=0;i<OQ_MAX;i++){
overlay_txqueue *queue=&overlay_tx[i];
overlay_stuff_packet(packet, queue, now);
}
if (next_packet.alarm)
schedule(&next_packet);
if(packet->buffer){
// send the packet
if (packet->buffer->position>=HEADERFIELDS_LEN){
// stuff rhizome announcements at the last moment
if (rhizome_enabled() && rhizome_http_server_running()){
overlay_rhizome_add_advertisements(packet->i,packet->buffer);
}
if (debug&DEBUG_PACKETCONSTRUCTION)
dump("assembled packet",&packet->buffer->bytes[0],packet->buffer->position);
overlay_broadcast_ensemble(packet->i, &packet->dest, packet->buffer->bytes, packet->buffer->position);
}
ob_free(packet->buffer);
overlay_address_clear();
RETURN(1);
}
RETURN(0);
}
// when the queue timer elapses, send a packet
void overlay_send_packet(struct sched_ent *alarm){
struct outgoing_packet packet;
bzero(&packet, sizeof(struct outgoing_packet));
overlay_fill_send_packet(&packet, gettime_ms());
}
// update time for next alarm and reschedule
void overlay_update_queue_schedule(overlay_txqueue *queue, struct overlay_frame *frame){
if (overlay_calc_queue_time(queue, frame)){
unschedule(&next_packet);
schedule(&next_packet);
}
}
static int
overlay_tick_interface(int i, time_ms_t now) {
struct outgoing_packet packet;
IN();
/* An interface with no speed budget is for listening only, so doesn't get ticked */
if (overlay_interfaces[i].bits_per_second<1
|| overlay_interfaces[i].state!=INTERFACE_STATE_UP) {
RETURN(0);
}
if (debug&DEBUG_OVERLAYINTERFACES) DEBUGF("Ticking interface #%d",i);
// initialise the packet buffer
bzero(&packet, sizeof(struct outgoing_packet));
overlay_init_packet(&packet, &overlay_interfaces[i], 1);
/* Add advertisements for ROUTES */
overlay_route_add_advertisements(packet.interface, packet.buffer);
/* Stuff more payloads from queues and send it */
overlay_fill_send_packet(&packet, now);
RETURN(0);
}
static long long
parse_quantity(char *q) {
int m;
char units[80];
if (strlen(q)>=80) return WHY("quantity string >=80 characters");
if (sscanf(q,"%d%s",&m,units)==2)
{
if (units[1]) return WHY("Units should be single character");
switch(units[0])
{
case 'k': return m*1000LL;
case 'K': return m*1024LL;
case 'm': return m*1000LL*1000LL;
case 'M': return m*1024LL*1024LL;
case 'g': return m*1000LL*1000LL*1000LL;
case 'G': return m*1024LL*1024LL*1024LL;
default:
return WHY("Illegal unit: should be k,K,m,M,g, or G.");
}
}
if (sscanf(q,"%d",&m)==1)
{
return m;
}
else
{
return WHY("Could not parse quantity");
}
}
static void
logServalPacket(int level, struct __sourceloc __whence, const char *message, const unsigned char *packet, size_t len) {
struct mallocbuf mb = STRUCT_MALLOCBUF_NULL;
if (serval_packetvisualise(XPRINTF_MALLOCBUF(&mb), message, packet, len) == -1)
WHY("serval_packetvisualise() failed");
else if (mb.buffer == NULL)
WHYF("serval_packetvisualise() output buffer missing, message=%s packet=%p len=%lu", alloca_toprint(-1, message, strlen(message)), packet, len);
else
logString(level, __whence, mb.buffer);
if (mb.buffer)
free(mb.buffer);
}