1 // This program is a UDP based tunneling of stdin/out Ethernet packets.
3 // A rrqnet program is a bi-directional networking plug that channels
4 // packets between a UDP port and stdin/out. It is configured on the
5 // command line with channel rules that declares which remotes it may
6 // communicate with. Allowed remotes are specified in the format
7 // "ip[/n][:port][=key]", to indicate which subnet and port to accept,
8 // and nominating the associated keyfile to use for channel
11 // The program maintains a table of actualized connections, as an
12 // association between MAC addresses and IP:port addresses. This table
13 // is used for resolving destination for outgoing packets, including
14 // the forwarding of broadcasts.
20 #include <linux/if_tun.h>
25 #include <sys/ioctl.h>
28 #include <sys/types.h>
37 // "Private Shared Key" details.
40 unsigned int seed; // Encryption seed
41 unsigned char *key; // Encryption key
42 unsigned int key_length; // Encryption key length
45 // Compacted IP address ipv4/ipv6
47 int width; // 4=ipv4 and 16=ipv6
49 unsigned char bytes[16];
55 // Details of channel rules.
57 char *source; // Orginal rule
59 unsigned int bits; // Bits of IP prefix
60 unsigned short port; // Port (0=any)
61 struct PSK psk; // Associated key
62 htable ignored_mac; // MAC to ignore by this spec
65 // Details of actualized connections.
67 struct SockAddr uaddr;
68 struct Allowed *spec; // Rule being instantiated
69 struct timeval rec_when; // Last received packet time, in seconds
72 // Details of an interface at a remote.
74 unsigned char mac[6]; // MAC address used last (key for by_mac table)
75 struct timeval rec_when; // Last packet time, in seconds
76 struct Remote *remote;
79 // Maximal packet size .. allow for jumbo frames (9000)
82 typedef struct _PacketItem {
87 unsigned char buffer[ BUFSIZE ];
90 typedef struct _ReaderData {
94 // heartbeat interval, in seconds
96 #define HEARTBEAT_MICROS ( HEARTBEAT * 1000000 )
98 // Macros for timing, for struct timeval variables
99 #define TIME_MICROS(TM) (((int64_t) (TM)->tv_sec * 1000000) + (TM)->tv_usec )
100 #define DIFF_MICROS(TM1,TM2) ( TIME_MICROS(TM1) - TIME_MICROS(TM2) )
102 // RECENT_MICROS(T,M) is the time logic for requiring a gap time (in
103 // milliseconds) before shifting a MAC to a new remote. The limit is
104 // 6s for broadcast and 20s for unicast.
105 #define RECENT_MICROS(T,M) ((M) < ((T)? 6000000 : 20000000 ))
107 // VERYOLD_MICROSS is used for discarding downlink remotes whose latest
108 // activity is older than this.
109 #define VERYOLD_MICROS 180000000
113 // Allowed remote specs are held in a table sorted by IP prefix.
115 struct Allowed **table;
119 // Actual remotes are kept in a hash table keyed by their +uaddr+
120 // field, and another hash table keps Interface records for all MAC
121 // addresses sourced from some remote, keyed by their +mac+ field. The
122 // latter is used both for resolving destinations for outgoing
123 // packets, and for limiting broadcast cycles. The former table is
124 // used for limiting incoming packets to allowed sources, and then
125 // decrypt the payload accordingly.
126 static int hashcode_uaddr(struct _htable *table,unsigned char *key);
127 static int hashcode_mac(struct _htable *table,unsigned char *key);
129 htable by_mac; // struct Interface hash table
130 htable by_addr; // struct Remote hash table
132 .by_mac = HTABLEINIT( struct Interface, mac, hashcode_mac ),
133 .by_addr = HTABLEINIT( struct Remote, uaddr, hashcode_uaddr )
136 #define Interface_LOCK if ( pthread_mutex_lock( &remotes.by_mac.lock ) ) { \
137 perror( "FATAL" ); exit( 1 ); }
139 #define Interface_UNLOCK if (pthread_mutex_unlock( &remotes.by_mac.lock ) ) { \
140 perror( "FATAL" ); exit( 1 ); }
142 #define Interface_FIND(m,r) \
143 htfind( &remotes.by_mac, m, (unsigned char **)&r )
145 #define Interface_ADD(r) \
146 htadd( &remotes.by_mac, (unsigned char *)r )
148 #define Interface_DEL(r) \
149 htdelete( &remotes.by_mac, (unsigned char *) r )
151 #define Remote_LOCK if ( pthread_mutex_lock( &remotes.by_addr.lock ) ) { \
152 perror( "FATAL" ); exit( 1 ); }
154 #define Remote_UNLOCK if ( pthread_mutex_unlock( &remotes.by_addr.lock ) ) { \
155 perror( "FATAL" ); exit( 1 ); }
157 #define Remote_FIND(a,r) \
158 htfind( &remotes.by_addr, (unsigned char *)a, (unsigned char **) &r )
160 #define Remote_ADD(r) \
161 htadd( &remotes.by_addr, (unsigned char *) r )
163 #define Remote_DEL(r) \
164 htdelete( &remotes.by_addr, (unsigned char *) r )
166 #define Ignored_FIND(a,m,x) \
167 htfind( &a->ignored_mac, m, (unsigned char **)&x )
169 #define Ignored_ADD(a,x) \
170 htadd( &a->ignored_mac, (unsigned char *)x )
173 static int stdio = 0; // Default is neither stdio nor tap
174 static char *tap = 0; // Name of tap, if any, or "-" for stdio
175 static int tap_fd = 0; // Also used for stdin in stdio mode
177 static int threads_count = 0;
178 static int buffers_count = 0;
180 // Setup for multicast channel
182 struct ip_mreqn group;
183 struct SockAddr sock;
188 // Flag to signal the UDP socket as being ipv6 or not (forced ipv4)
191 // The given UDP source address, if any
194 unsigned char address[16];
197 // Flag to indicate tpg transport patch = avoid UDP payload of 1470
198 // bytes by adding 2 tag-along bytes
199 static int tpg_quirk = 0;
201 // Flag whether to make some stderr outputs or not.
202 // 1 = normal verbosity, 2 = more output, 3 = source debug level stuff
205 // Note: allows a thread to lock/unlock recursively
206 static pthread_mutex_t crypting = PTHREAD_MUTEX_INITIALIZER;
208 // Note: allows a thread to lock/unlock recursively
209 static pthread_mutex_t printing = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
212 if ( pthread_mutex_lock( &printing ) ) { perror( "FATAL" ); exit(1); }
214 #define PRINTUNLOCK \
215 if ( pthread_mutex_unlock( &printing ) ) { perror( "FATAL" ); exit(1); }
217 #define PRINT( X ) { PRINTLOCK; X; PRINTUNLOCK; }
219 #define VERBOSEOUT(fmt, ...) \
220 if ( verbose >= 1 ) PRINT( fprintf( stderr, fmt, ##__VA_ARGS__ ) )
222 #define VERBOSE2OUT(fmt, ...) \
223 if ( verbose >= 2 ) PRINT( fprintf( stderr, fmt, ##__VA_ARGS__ ) )
225 #define VERBOSE3OUT(fmt, ...) \
226 if ( verbose >= 3 ) PRINT( fprintf( stderr, fmt, ##__VA_ARGS__ ) )
228 // The actual name of this program (argv[0])
229 static unsigned char *progname;
231 // Compute a hashcode for the given SockAddr key
232 static int hashcode_uaddr(
233 __attribute__((unused)) struct _htable *table,unsigned char *key)
235 struct SockAddr *s = (struct SockAddr *) key;
236 key = (unsigned char*) &s->in;
237 unsigned char *e = key + ( ( s->in.sa_family == AF_INET )?
238 sizeof( struct sockaddr_in ) :
239 sizeof( struct sockaddr_in6 ) );
247 // Compute a hashcode for the given MAC addr key
248 static int hashcode_mac(struct _htable *table,unsigned char *key) {
251 if ( table->size == 256 ) {
252 for ( ; i < 6; i++ ) {
257 uint16_t *p = (uint16_t *) key;
258 for ( ; i < 3; i++ ) {
264 // Make a text representation of bytes as ipv4 or ipv6
265 static char *inet_nmtoa(unsigned char *b,int w) {
266 static char buffer[20000];
270 sprintf( p,"%d.%d.%d.%d", b[0], b[1], b[2], b[3] );
271 } else if ( w == 16 ){
273 "%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x",
274 b[0], b[1], b[2], b[3],
275 b[4], b[5], b[6], b[7],
276 b[8], b[9], b[10], b[11],
277 b[12], b[13], b[14], b[15] );
279 VERBOSE3OUT( "HEX data of %d bytes\n", w );
280 for ( ; i < w && i < 19000; i++, p += 3 ) {
281 sprintf( p, "%02x:", b[i] );
290 // Form a MAC address string from 6 MAC address bytes, into one of the
291 // 4 static buffer, whose use are cycled.
292 static char *inet_mtoa(unsigned char *mac) {
293 static char buffer[4][30];
298 sprintf( buffer[i], "%02x:%02x:%02x:%02x:%02x:%02x",
299 mac[0], mac[1], mac[2], mac[3], mac[4], mac[5] );
303 // Form a socket address string from Sockaddr, into one of the
304 // 4 static buffer, whose use are cycled.
305 static char *inet_stoa(struct SockAddr *a) {
306 static char buffer[1000];
307 static char out[4][1000];
312 if ( a->in.sa_family == AF_INET ) {
313 sprintf( out[i], "%s:%d",
314 inet_ntop( AF_INET, &a->in4.sin_addr, buffer, 100 ),
315 ntohs( a->in4.sin_port ) );
316 } else if ( a->in.sa_family == AF_INET6 ) {
317 sprintf( out[i], "[%s]:%d",
318 inet_ntop( AF_INET6, &a->in6.sin6_addr, buffer, 100 ),
319 ntohs( a->in6.sin6_port ) );
321 sprintf( out[i], "<tap/stdio>" );
326 // Debugging: string representation of an Allowed record.
327 static char *show_allowed(struct Allowed *a) {
328 static char buffer[20000];
330 sprintf( buffer, "{tap/stdio}" );
332 sprintf( buffer, "%hd (%d) %s %p",
333 a->port, a->bits, inet_nmtoa( a->addr.bytes, a->addr.width ),
339 // Recognize uplink specification
340 static int is_uplink(struct Allowed *a) {
341 return a->bits == (unsigned int) ( a->addr.width * 8 ) && a->port != 0;
344 // Add a new Interface for a Remote. If non-null, the interface is
345 // also added to the interface table.
346 static struct Interface *add_interface(unsigned char *mac,struct Remote *r) {
347 struct Interface *x = calloc( 1, sizeof( struct Interface ) );
348 memcpy( x->mac, mac, sizeof( x->mac ) );
356 // Add a new remote for a given address and spec.
357 static struct Remote *add_remote(struct SockAddr *a,struct Allowed *s) {
358 struct Remote *r = calloc( 1, sizeof( struct Remote ) );
360 memcpy( &r->uaddr, a, sizeof( r->uaddr ) );
363 VERBOSE2OUT( "add_remote %s from spec: %s\n",
364 inet_stoa( &r->uaddr ),
365 ( s == 0 )? ( (a == 0)? "{tap/stdio}" : "{multicast}" )
366 : show_allowed( s ) );
371 // Add a new ignored interface on a channel
372 static int add_ignored(struct Allowed *link,unsigned char *mac) {
373 struct Interface *x = add_interface( mac, 0 );
375 return 1; // error: out of memory
377 Ignored_ADD( link, x );
381 // Parse ignored interfaces
382 // Comma separated list of MAC addresses
383 static int parse_ignored_interfaces(char *arg,struct Allowed *link) {
384 int a, b, c, d, e, f, g;
386 if ( sscanf( arg,"%x:%x:%x:%x:%x:%x%n",&a,&b,&c,&d,&e,&f,&g ) != 6 ) {
390 if ( (a|b|c|d|e|f) & ~0xff ) {
391 return 1; // some %x is not hex
393 unsigned char mac[6] = { a, b, c, d, e, f };
394 if ( add_ignored( link, mac ) ) {
398 VERBOSEOUT( "Ignoring: %s on channel %s\n",
399 inet_mtoa( mac ), link->source );
404 if ( *(arg++) != ',' ) {
405 return 1; // Not comma separated
411 //** IP address parsing utility
412 // Clear bits after <bits>
413 static void clearbitsafter(struct CharAddr *a,unsigned int bits) {
414 unsigned int max = a->width * 8;
416 for ( i = a->width; i < 16; i++ ) {
419 for ( i = a->width - 1; i >= 0; i--, max -= 8 ) {
420 if ( max - 8 < bits ) {
425 if ( i >= 0 && max >= bits ) {
426 a->bytes[ i ] &= ( 0xFF << ( bits - max ) );
430 //** IP address parsing utility
431 // Find the PSK for the given +file+ in the +loaded+ table (of +count+ size)
432 static struct PSK *findLoadedKeyfile(char *file,struct PSK *loaded,int count) {
433 VERBOSE3OUT( "find %s\n", file );
434 for ( count--; count >= 0; count-- ) {
435 if ( strcmp( file, loaded[ count ].keyfile ) ) {
436 VERBOSE3OUT( "found %d\n", count );
437 return &loaded[ count ];
440 VERBOSE3OUT( "found nothing\n" );
444 //** IP address parsing utility
445 // Load a key file into dynamically allocated memory, and update the
446 // given PSK header for it.
447 static void loadkey(struct PSK *psk) {
448 static struct PSK *loaded = 0;
449 static int count = 0;
450 if ( psk->keyfile == 0 ) {
453 struct PSK *old = findLoadedKeyfile( psk->keyfile, loaded, count );
455 memcpy( psk, old, sizeof( struct PSK ) );
461 struct stat filestat;
462 psk->keyfile = strdup( psk->keyfile );
463 int fd = open( (char*) psk->keyfile, O_RDONLY );
466 perror( "open key file" );
469 if ( fstat( fd, &filestat ) ) {
470 perror( "stat of key file" );
473 psk->key_length = filestat.st_size;
474 if ( psk->key_length < 256 ) {
475 fprintf( stderr, "Too small key file: %d %s\n", psk->key_length,
479 psk->key = malloc( psk->key_length );
480 if ( psk->key == 0 ) {
481 fprintf( stderr, "Cannot allocate %d bytes for %s\n",
482 psk->key_length, psk->keyfile );
487 while ( ( n = read( fd, p, e ) ) > 0 ) {
493 fprintf( stderr, "Failed loading key %s\n", psk->keyfile );
496 for ( e = 0; (unsigned) e < psk->key_length; e++ ) {
497 psk->seed += psk->key[ e ];
499 if ( psk->seed == 0 ) {
500 fprintf( stderr, "Bad key %s; adds up to 0\n", psk->keyfile );
505 loaded = realloc( loaded, ( count * sizeof( struct PSK ) ) );
507 loaded = malloc( sizeof( struct PSK ) );
509 memcpy( &loaded[ count-1 ], psk, sizeof( struct PSK ) );
510 VERBOSE3OUT( "%d: %s %d %p %d\n", count-1, psk->keyfile, psk->seed,
511 psk->key, psk->key_length );
514 //** IP address parsing utility
515 // Fill out a CharAddr and *port from a SockAddr
516 static void set_charaddrport(
517 struct CharAddr *ca,unsigned short *port,struct SockAddr *sa)
519 memset( ca, 0, sizeof( struct CharAddr ) );
520 ca->width = ( sa->in.sa_family == AF_INET )? 4 : 16;
521 if ( ca->width == 4 ) {
522 memcpy( &ca->in4, &sa->in4.sin_addr, 4 );
523 *port = ntohs( sa->in4.sin_port );
525 memcpy( &ca->in6, &sa->in6.sin6_addr, 16 );
526 *port = ntohs( sa->in6.sin6_port );
530 //** IP address parsing utility
531 // Fill out a SockAddr from a CharAddr and port
532 static void set_sockaddr(struct SockAddr *sa,struct CharAddr *ca,int port) {
533 memset( sa, 0, sizeof( struct SockAddr ) );
534 if ( ca->width == 4 ) {
535 sa->in4.sin_family = AF_INET;
536 sa->in4.sin_port = htons( port );
537 memcpy( &sa->in4.sin_addr, &ca->in4, 4 );
539 sa->in6.sin6_family = AF_INET6;
540 sa->in6.sin6_port = htons( port );
541 memcpy( &sa->in6.sin6_addr, &ca->in6, 16 );
545 //** IP address parsing utility
546 // Capture an optional port sub phrase [:<port>]
547 static int parse_port(char *port,struct Allowed *into) {
552 if ( sscanf( port, "%d", &p ) != 1 || p < 1 || p > 65535 ) {
561 //** IP address parsing utility
562 // Capture an optional bits sub phrase [/<bits>]
563 static int parse_bits(char *bits,int max,struct Allowed *into) {
568 if ( sscanf( bits, "%d", &b ) != 1 || b < 0 || b > max ) {
576 //** IP address parsing utility
577 // Parse a command line argument as a declaration of an allowed
578 // remote into the given <addr>.
579 // Return 0 if ok and 1 otherwise
580 // Formats: <ipv4-address>[/<bits>][:<port>][=keyfile]
581 // Formats: <ipv6-address>[/<bits>][=keyfile]
582 // Formats: \[<ipv6-address>[/<bits>]\][:<port>][=keyfile]
583 // Formats: hostname:port[=keyfile]
584 static int parse_allowed(char *arg,struct Allowed *into) {
585 static char buffer[10000];
586 int n = strlen( arg );
588 return 1; // excessively large argument
590 strcpy( buffer, arg );
592 char * keyfile = strchr( buffer, '=' );
595 into->psk.keyfile = keyfile;
597 #define B(b) b, b+1, b+2, b+3
598 if ( sscanf( buffer, "%hhu.%hhu.%hhu.%hhu", B(into->addr.bytes) ) == 4 ) {
601 into->addr.width = 4;
602 if ( parse_port( strchr( buffer, ':' ), into ) ) {
603 fprintf( stderr, "bad port\n" );
606 if ( parse_bits( strchr( buffer, '/' ), 32, into ) ) {
607 fprintf( stderr, "bad bits\n" );
613 char * address = buffer;
615 if ( *buffer == '[' ) {
616 // bracketed form, necessary for port
617 char *end = strchr( buffer, ']' );
619 return 1; // bad argument
623 if ( *end == ':' && parse_port( end, into ) ) {
627 into->addr.width = 16;
628 if ( parse_bits( strchr( address, '/' ), 128, into ) ) {
631 if ( inet_pton( AF_INET6, address, into->addr.bytes ) != 1 ) {
632 return 1; // Bad IPv6
637 //** IP address parsing utility
638 // Add a new channel spec into the <allowed> table
639 // spec == 0 for the tap/stdio channel
640 static struct Allowed *add_allowed(char *spec) {
641 struct Allowed *into = calloc( 1, sizeof(struct Allowed) );
642 htable x = HTABLEINIT( struct Interface, mac, hashcode_mac );
643 into->ignored_mac = x;
645 if ( parse_allowed( spec, into ) ) {
646 fprintf( stderr, "Bad remote spec: %s\n", spec );
651 if ( allowed.table == 0 ) {
653 allowed.table = calloc( 1, sizeof(struct Allowed*) );
658 allowed.table = realloc( allowed.table,
659 allowed.count * sizeof(struct Allowed*) );
660 if ( allowed.table == 0 ) {
661 fprintf( stderr, "OUT OF MEMORY\n" );
665 allowed.table[i] = into;
667 loadkey( &into->psk );
668 VERBOSE3OUT( "Allowed %s { %s }\n", into->source, show_allowed( into ) );
669 if ( is_uplink( into ) ) {
670 struct SockAddr addr;
671 set_sockaddr( &addr, &into->addr, into->port );
672 VERBOSEOUT( "Add uplink %s\n", show_allowed( into ) );
673 (void) add_remote( &addr, into );
678 static int parse_threads_count(char *arg) {
679 if ( ( sscanf( arg, "%u", &threads_count ) != 1 ) || threads_count < 1 ) {
682 VERBOSEOUT( "** Threads count = %d\n", threads_count );
686 static int parse_buffers_count(char *arg) {
687 if ( ( sscanf( arg, "%u", &buffers_count ) != 1 ) || buffers_count < 1 ) {
690 VERBOSEOUT( "** Buffers count = %d\n", buffers_count );
694 //** IP address parsing utility for multicast phrase
695 // Return 0 if ok and 1 otherwise
696 // Formats: <ipv4-address>:<port>[=keyfile]
697 // The ipv4 address should be a multicast address in ranges
698 // 224.0.0.0/22, 232.0.0.0/7, 234.0.0.0/8 or 239.0.0.0/8
699 // though it's not checked here.
700 static int parse_mcast(char *arg) {
701 static char buffer[10000];
702 int n = strlen( arg );
704 return 1; // excessively large argument
706 memcpy( buffer, arg, n );
707 char *p = buffer + n - 1;
708 for ( ; p > buffer && *p != ':' && *p != '='; p-- ) { }
710 mcast.psk.keyfile = p+1;
712 loadkey( &mcast.psk );
713 for ( ; p > buffer && *p != ':' ; p-- ) { }
716 fprintf( stderr, "Multicast port is required\n" );
717 return 1; // Port number is required
720 if ( inet_pton( AF_INET, buffer, &mcast.group.imr_multiaddr.s_addr )==0 ) {
721 fprintf( stderr, "Multicast address required\n" );
725 long int port = strtol( p, &e, 10 );
726 if ( *e != 0 || port < 1 || port > 65535 ) {
727 fprintf( stderr, "Bad multicast port\n" );
730 mcast.group.imr_address.s_addr = htonl(INADDR_ANY);
731 mcast.sock.in4.sin_family = AF_INET;
732 mcast.sock.in4.sin_addr.s_addr = htonl(INADDR_ANY);
733 mcast.sock.in4.sin_port = htons( atoi( p ) );
737 //** IP address parsing utility for UDP source address
738 // Return 0 if ok and 1 otherwise
739 // Formats: <ipv4-address> or <ipv6-address>
740 // The ipv4 address should be a multicast address in ranges
741 // 224.0.0.0/22, 232.0.0.0/7, 234.0.0.0/8 or 239.0.0.0/8
742 // though it's not checked here.
743 static int parse_udp_source(char *arg) {
744 if ( inet_pton( AF_INET6, arg, udp_source.address ) ) {
745 // An ipv6 address is given.
747 udp_source.family = AF_INET6;
752 if ( ! inet_pton( AF_INET, arg, udp_source.address ) ) {
756 // An ipv4 address is given.
758 // Translate into ipv6-encoded ipv4
759 memmove( udp_source.address + 12, udp_source.address, 4 );
760 memset( udp_source.address, 0, 10 );
761 memset( udp_source.address + 10, -1, 2 );
762 udp_source.family = AF_INET6;
764 udp_source.family = AF_INET;
769 // Utility that sets upt the multicast socket, which is used for
770 // receiving multicast packets.
771 static void setup_mcast() {
772 // set up ipv4 socket
773 if ( ( mcast.fd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == 0 ) {
774 perror( "creating socket");
777 if ( setsockopt( mcast.fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
778 (char *) &mcast.group, sizeof( mcast.group ) ) < 0) {
779 perror( "Joining multicast group" );
783 if ( setsockopt( mcast.fd, SOL_SOCKET, SO_REUSEADDR,
784 &reuse, sizeof( int ) ) < 0 ) {
785 perror( "SO_REUSEADDR" );
788 if ( bind( mcast.fd, (struct sockaddr*) &mcast.sock.in,
789 sizeof( struct sockaddr ) ) ) {
790 fprintf( stderr, "Error binding socket!\n");
793 // Change mcast address to be the group multiaddress, and add
794 // a persistent "remote" for it.
795 mcast.sock.in4.sin_addr.s_addr = mcast.group.imr_multiaddr.s_addr;
796 add_remote( &mcast.sock, 0 );
799 // Find the applicable channel rule for a given ip:port address
800 static struct Allowed *is_allowed_remote(struct SockAddr *addr) {
802 int width = ( addr->in.sa_family == AF_INET )? 4 : 16;
805 for ( ; (unsigned) i < allowed.count; i++ ) {
806 struct Allowed *a = allowed.table[i];
807 if ( a->addr.width != width ) {
810 set_charaddrport( &ca, &port, addr );
811 if ( a->port != 0 && a->port != port ) {
814 clearbitsafter( &ca, a->bits );
815 if ( memcmp( &ca, &a->addr, sizeof( struct CharAddr ) ) == 0 ) {
819 return 0; // Disallowed
822 // Simple PSK encryption:
824 // First, xor each byte with a key byte that is picked from the key
825 // by means of an index that includes the prior encoding. Also,
826 // compute the sum of encrypted bytes into a "magic" that is added the
827 // "seed" for seeding the random number generator. Secondly reorder
828 // the bytes using successive rand number picks from the seeded
831 static void encrypt(unsigned char *buf,unsigned int n,struct PSK *psk) {
836 VERBOSE3OUT( "encrypt by %s %p\n", psk->keyfile, psk->key );
837 for ( k = 0, r = 0, magic = 0; k < n; k++ ) {
838 r = ( r + magic + k ) % psk->key_length;
839 buf[k] ^= psk->key[ r ];
842 pthread_mutex_lock( &crypting );
843 srand( psk->seed + magic );
844 for ( k = 0; k < n; k++ ) {
850 pthread_mutex_unlock( &crypting );
853 // Corresponding decryption procedure .
854 static void decrypt(unsigned char *buf,unsigned int n,struct PSK *psk) {
855 unsigned int randoms[ BUFSIZE ];
859 unsigned int magic = 0;
860 for ( k = 0; k < n; k++ ) {
863 pthread_mutex_lock( &crypting );
864 srand( psk->seed + magic );
865 for ( k = 0; k < n; k++ ) {
866 randoms[k] = rand() % n;
868 pthread_mutex_unlock( &crypting );
869 for ( k = n; k > 0; ) {
875 for ( k = 0, r = 0, magic = 0; k < n; k++ ) {
876 r = ( r + magic + k ) % psk->key_length;
878 buf[k] ^= psk->key[r];
882 // Write a buffer data to given file descriptor (basically tap_fd in
883 // this program). This is never fragmented.
884 static int dowrite(int fd, unsigned char *buf, int n) {
886 if ( ( w = write( fd, buf, n ) ) < 0){
887 perror( "Writing data" );
893 // Write to the tap/stdio; adding length prefix for stdio
894 static int write_tap(unsigned char *buf, int n) {
895 uint8_t tag0 = *( buf + 12 );
897 uint16_t size = ntohs( *(uint16_t*)(buf + 16) );
898 if ( size <= 1500 ) {
899 if ( ( verbose >= 2 ) && ( n != size + 14 ) ) {
900 VERBOSEOUT( "clip %d to %d\n", n, size + 14 );
902 n = size + 14; // Clip of any tail
906 uint16_t plength = htons( n );
907 if ( dowrite( 1, (unsigned char *) &plength,
908 sizeof( plength ) ) < 0 ) {
911 return dowrite( 1, buf, n );
913 return dowrite( tap_fd, buf, n );
916 // Write a packet via the given Interface with encryption as specified.
917 static void write_remote(unsigned char *buf, int n,struct Remote *r) {
919 unsigned char output[ BUFSIZE ];
921 VERBOSE2OUT( "SEND %d bytes to %s\n", n, inet_stoa( &r->uaddr ) );
923 VERBOSE2OUT( "SEND %d bytes %s -> %s to %s\n", n,
924 inet_mtoa( buf+6 ), inet_mtoa( buf ),
925 inet_stoa( &r->uaddr ) );
927 memcpy( output, buf, n ); // Use the private buffer for delivery
928 // Apply the TPG quirk
929 if ( tpg_quirk && ( n > 1460 ) && ( n < 1478 ) ) {
930 VERBOSE2OUT( "tpg quirk applied\n" );
931 n = 1478; // Add some "random" tag-along bytes
933 if ( r->spec == 0 ) {
934 if ( r->uaddr.in.sa_family == 0 ) {
935 // Output to tap/stdio
936 if ( write_tap( buf, n ) < 0 ) {
938 fprintf( stderr, "Cannot write to tap/stdio: exiting!\n" );
943 // Fall through for multicast
944 if ( mcast.psk.keyfile ) {
945 encrypt( output, n, &mcast.psk );
947 } else if ( r->spec->psk.keyfile ) {
948 encrypt( output, n, &r->spec->psk );
950 struct sockaddr *sock = &r->uaddr.in;
952 if ( sock->sa_family == AF_INET6 ) {
953 // Note that the size of +struct sockaddr_in6+ is actually
954 // larger than the size of +struct sockaddr+ (due to the
955 // addition of the +sin6_flowinfo+ field). It results in the
956 // following cuteness for passing arguments to +sendto+.
957 size = sizeof( struct sockaddr_in6 );
958 VERBOSE2OUT( "IPv6 UDP %d %s\n",
959 udp_fd, inet_stoa( (struct SockAddr*) sock ) );
961 size = sizeof( struct sockaddr_in );
962 VERBOSE2OUT( "IPv4 UDP %d %s\n",
963 udp_fd, inet_stoa( (struct SockAddr*) sock ) );
965 VERBOSE2OUT( "SEND %d bytes to %s [%s -> %s]\n",
966 n, inet_stoa( (struct SockAddr*) sock ),
967 ( n < 12 )? "" : inet_mtoa( buf+6 ),
968 ( n < 12 )? "" : inet_mtoa( buf )
970 // IS sendto thread safe??
971 if ( sendto( udp_fd, output, n, 0, sock, size ) < n ) {
972 perror( "Writing socket" );
973 // Invalidate remote temporarily instead? But if it's an
974 // "uplink" it should be retried eventually...
975 // For now: just ignore the error.
980 // Delete a Remote and all its interfaces
981 static void delete_remote(struct Remote *r) {
982 VERBOSE2OUT( "DELETE Remote and all its interfaces %s\n",
983 inet_stoa( &r->uaddr ) );
987 for ( ; i < remotes.by_mac.size; i++ ) {
988 unsigned char *tmp = remotes.by_mac.data[i];
989 if ( tmp == 0 || tmp == (unsigned char *)1 ) {
992 x = (struct Interface *) tmp;
993 if ( x->remote == r ) {
1003 // Unmap an ipv4-mapped ipv6 address
1004 static void unmap_if_mapped(struct SockAddr *s) {
1005 if ( s->in.sa_family != AF_INET6 ||
1006 memcmp( "\000\000\000\000\000\000\000\000\000\000\377\377",
1007 &s->in6.sin6_addr, 12 ) ) {
1010 VERBOSE2OUT( "unmap %s\n",
1011 inet_nmtoa( (unsigned char*) s, sizeof( struct SockAddr ) ) );
1012 s->in.sa_family = AF_INET;
1013 memcpy( &s->in4.sin_addr, s->in6.sin6_addr.s6_addr + 12, 4 );
1014 memset( s->in6.sin6_addr.s6_addr + 4, 0, 12 );
1015 VERBOSE2OUT( "becomes %s\n",
1016 inet_nmtoa( (unsigned char*) s, sizeof( struct SockAddr ) ) );
1019 // Route the packet from the given src
1020 static struct Interface *input_check(
1021 unsigned char *buf,ssize_t len,struct SockAddr *src )
1023 VERBOSE2OUT( "RECV %ld bytes from %s\n", len, inet_stoa( src ) );
1024 struct Remote *r = 0;
1025 struct timeval now = { 0 };
1026 if ( gettimeofday( &now, 0 ) ) {
1027 perror( "RECV time" );
1028 now.tv_sec = time( 0 );
1030 Remote_FIND( src, r );
1032 struct Allowed *a = is_allowed_remote( src );
1034 VERBOSEOUT( "Ignoring %s\n", inet_stoa( src ) );
1035 return 0; // Disallowed
1037 VERBOSEOUT( "New remote %s by %s\n", inet_stoa( src ), a->source );
1038 r = add_remote( src, a );
1039 //r->rec_when = now; // Set activity stamp of new remote
1042 // Ignore short data, but maintain channel
1043 r->rec_when = now; // Update activity stamp touched remote
1045 VERBOSEOUT( "Ignoring %ld bytes from %s\n",
1046 len, inet_stoa( src ) );
1050 // Now decrypt the data as needed
1052 if ( r->spec->psk.seed ) {
1053 decrypt( buf, len, &r->spec->psk );
1055 } else if ( r->uaddr.in.sa_family == 0 && mcast.psk.keyfile ) {
1056 decrypt( buf, len, &mcast.psk );
1058 VERBOSE2OUT( "RECV %s -> %s from %s\n",
1059 inet_mtoa( buf+6 ), inet_mtoa( buf ),
1060 inet_stoa( &r->uaddr ) );
1061 // Note: the payload is now decrypted, and known to be from +r+
1062 struct Interface *x = 0;
1063 // Packets concerning an ignored interface should be ignored.
1064 if ( r->spec && r->spec->ignored_mac.data ) {
1065 Ignored_FIND( r->spec, buf+6, x );
1067 VERBOSE2OUT( "Dropped MAC %s from %s on %s\n",
1068 inet_mtoa( buf+6 ), inet_stoa( &r->uaddr ),
1072 Ignored_FIND( r->spec, buf, x );
1074 VERBOSE2OUT( "Dropped MAC %s to %s on %s\n",
1075 inet_mtoa( buf ), inet_stoa( &r->uaddr ),
1080 Interface_FIND( buf+6, x );
1082 // Totally new MAC. Should bind it to the remote
1083 VERBOSEOUT( "New MAC %s from %s\n",
1084 inet_mtoa( buf+6 ), inet_stoa( src ) );
1085 x = add_interface( buf+6, r );
1086 r->rec_when = now; // Update activity stamp for remote
1090 // Seen that MAC already
1091 if ( x->remote == r ) {
1092 VERBOSE2OUT( "RECV %s from %s again\n",
1093 inet_mtoa( buf+6 ), inet_stoa( &x->remote->uaddr ) );
1094 r->rec_when = now; // Update activity stamp
1095 x->rec_when = now; // Update activity stamp
1098 // MAC clash from two different connections
1100 // x->remote = previous
1101 VERBOSE2OUT( "RECV %s from %s previously from %s\n",
1103 inet_stoa( &r->uaddr ),
1104 inet_stoa( &x->remote->uaddr ) );
1106 // The packet source MAC has arrived on other than its
1107 // previous channel. It thus gets dropped if tap/stdin is the
1108 // primary channel, or the time since the last packet for that
1109 // interface is less than RECENT_MICROS, with different limits
1110 // for broadcast and unicast.
1111 int64_t dmac = DIFF_MICROS( &now, &x->rec_when);
1112 if ( x->remote->spec == 0 || RECENT_MICROS( *buf & 1, dmac ) ) {
1113 if ( verbose >= 2 ) {
1116 "Dropped. MAC %s (%ld) from %s, should be %s\n",
1117 inet_mtoa( buf+6 ), dmac,
1118 inet_stoa( src ), inet_stoa( &x->remote->uaddr ) );
1122 // Check if previous package on the interface was recent
1123 } else if ( r->uaddr.in.sa_family ) {
1124 // Multicast incoming clashing with tap/stdio
1125 VERBOSE3OUT( "Dropped multicast loopback\n" );
1129 // New remote takes over the MAC
1130 VERBOSEOUT( "MAC %s from %s cancels previous %s\n",
1131 inet_mtoa( buf+6 ), inet_stoa( src ),
1132 inet_stoa( &x->remote->uaddr ) );
1133 x->remote = r; // Change remote for MAC
1134 // Note that this may leave the old x->remote without any interface
1135 r->rec_when = now; // Update activity stamp
1136 x->rec_when = now; // Update activity stamp
1140 // Check packet and deliver out
1141 static void route_packet(unsigned char *buf,int len,struct SockAddr *src) {
1142 struct Interface *x = input_check( buf, len, src );
1144 return; // not a nice packet
1146 if ( ( *buf & 1 ) == 0 ) {
1148 struct Interface *y = 0; // reuse for destination interface
1149 Interface_FIND( buf, y );
1151 VERBOSE2OUT( "RECV %s -> %s from %s without channel and dropped\n",
1152 inet_mtoa( buf+6 ), inet_mtoa( buf ),
1153 inet_stoa( &x->remote->uaddr ) );
1156 if ( x->remote == y->remote ) {
1157 VERBOSEOUT( "RECV loop for %s -> %s from %s to %s\n",
1158 inet_mtoa( buf+6 ), inet_mtoa( buf ),
1159 inet_stoa( &x->remote->uaddr ),
1160 inet_stoa( &y->remote->uaddr ) );
1161 Interface_DEL( y ); // Need to see this interface again
1164 VERBOSE2OUT( "RECV route %s -> %s to %s\n",
1165 inet_mtoa( buf+6 ), inet_mtoa( buf ),
1166 inet_stoa( &y->remote->uaddr ) );
1167 write_remote( buf, len, y->remote );
1170 // broadcast. +x+ is source interface
1171 // x->rec_when is not updated
1172 struct timeval now = { 0 };
1173 if ( gettimeofday( &now, 0 ) ) {
1174 perror( "RECV time" );
1175 now.tv_sec = time( 0 );
1177 VERBOSE2OUT( "BC %s -> %s from %s\n",
1178 inet_mtoa( buf+6 ), inet_mtoa( buf ),
1179 inet_stoa( &x->remote->uaddr ) );
1183 for ( ; i < remotes.by_addr.size; i++ ) {
1184 unsigned char *tmp = remotes.by_addr.data[i];
1185 if ( tmp == 0 || tmp == (unsigned char *)1 ) {
1188 r = (struct Remote *) tmp;
1189 VERBOSE3OUT( "BC check %s\n", inet_stoa( &r->uaddr ) );
1190 if ( r == x->remote ) {
1191 VERBOSE3OUT( "BC r == x->remote\n" );
1194 if ( r->spec && ! is_uplink( r->spec ) &&
1195 DIFF_MICROS( &now, &r->rec_when ) > VERYOLD_MICROS ) {
1196 // remove old downlink connection
1197 VERBOSEOUT( "Old remote discarded %s (%ld)\n",
1198 inet_stoa( &r->uaddr ),
1199 TIME_MICROS( &r->rec_when ) );
1200 // Removing a downlink might have threading implications
1204 // Send packet to the remote
1205 // Only no-clash or to the tap/stdin
1206 write_remote( buf, len, r );
1211 // The packet handling queues
1218 // The threadcontrol program for handling packets.
1219 static void *packet_handler(void *data) {
1222 PacketItem *todo = (PacketItem *) Queue_getItem( &todolist.full );
1223 if ( todo->fd == mcast.fd ) {
1224 // Patch multicast address as source for multicast packet
1225 route_packet( todo->buffer, todo->len, &mcast.sock );
1228 unmap_if_mapped( &todo->src );
1230 route_packet( todo->buffer, todo->len, &todo->src );
1232 Queue_addItem( &todolist.free, (QueueItem*) todo );
1237 void todolist_initialize(int nbuf,int nthr) {
1238 if ( pthread_mutex_init( &todolist.full.mutex, 0 ) ||
1239 sem_init( &todolist.full.count, 0, 0 ) ) {
1243 if ( pthread_mutex_init( &todolist.free.mutex, 0 ) ||
1244 sem_init( &todolist.free.count, 0, 0 ) ) {
1248 if ( sem_init( &todolist.reading, 0, 1 ) ) {
1252 Queue_initialize( &todolist.free, nbuf, sizeof( PacketItem ) );
1253 for ( ; nthr > 0; nthr-- ) {
1254 pthread_t thread; // Temporary thread id
1255 pthread_create( &thread, 0, packet_handler, 0 );
1259 // Read a full UDP packet into the given buffer, associate with a
1260 // connection, or create a new connection, the decrypt the as
1261 // specified, and capture the sender MAC address. The connection table
1262 // is updated for the new MAC address, However, if there is then a MAC
1263 // address clash in the connection table, then the associated remote
1264 // is removed, and the packet is dropped.
1265 static void *doreadUDP(void *data) {
1266 int fd = ((ReaderData *) data)->fd;
1268 PacketItem *todo = (PacketItem *) Queue_getItem( &todolist.free );
1270 udp6? sizeof( todo->src.in6 ) : sizeof( todo->src.in4 );
1271 memset( &todo->src, 0, sizeof( todo->src ) );
1273 todo->len = recvfrom(
1274 fd, todo->buffer, BUFSIZE, 0, &todo->src.in, &addrlen );
1275 if ( todo->len == -1) {
1276 perror( "Receiving UDP" );
1280 if ( todo->len == 17 &&
1281 memcmp( todo->buffer, "STOPSTOPSTOPSTOP", 16 ) == 0 ) {
1285 Queue_addItem( &todolist.full, (QueueItem*) todo );
1290 // Read up to n bytes from the given file descriptor into the buffer
1291 static int doread(int fd, unsigned char *buf, int n) {
1293 if ( ( len = read( fd, buf, n ) ) < 0 ) {
1294 perror( "Reading stdin" );
1300 // Read n bytes from the given file descriptor into the buffer.
1301 // If partial is allowed, then return amount read, otherwise keep
1302 // reading until full.
1303 static int read_into(int fd, unsigned char *buf, int n,int partial) {
1306 if ( (r = doread( fd, buf, x ) ) == 0 ) {
1318 // Go through all uplinks and issue a "heart beat"
1319 static void heartbeat(int fd) {
1320 static unsigned char data[10];
1321 VERBOSE3OUT( "heartbeat fd=%d\n", fd );
1325 if ( gettimeofday( &now, 0 ) ) {
1326 perror( "HEARTBEAT time" );
1327 now.tv_sec = time( 0 );
1331 for ( ; i < remotes.by_addr.size; i++ ) {
1332 unsigned char *tmp = remotes.by_addr.data[i];
1333 if ( tmp == 0 || tmp == (unsigned char *)1 ) {
1336 r = (struct Remote *) tmp;
1337 VERBOSE3OUT( "heartbeat check %s\n", inet_stoa( &r->uaddr ) );
1338 if ( r->spec && is_uplink( r->spec ) ) {
1339 if ( DIFF_MICROS( &now, &r->rec_when ) > HEARTBEAT_MICROS ) {
1340 VERBOSE3OUT( "heartbeat %s\n", inet_stoa( &r->uaddr ) );
1341 write_remote( data, 0, r );
1348 // Tell how to use this program and exit with failure.
1349 static void usage(void) {
1350 fprintf( stderr, "Packet tunneling over UDP, multiple channels, " );
1351 fprintf( stderr, "version 1.5.3\n" );
1352 fprintf( stderr, "Usage: " );
1353 fprintf( stderr, "%s [options] port [remote]+ \n", progname );
1354 fprintf( stderr, "** options must be given or omitted in order!!\n" );
1355 fprintf( stderr, " -v = verbose log, -vv or -vvv for more logs\n" );
1356 fprintf( stderr, " -tpg = UDP transport quirk: avoid bad sizes\n" );
1357 fprintf( stderr, " -4 = use an ipv4 UDP socket\n" );
1358 fprintf( stderr, " -B n = use n buffers (2*threads) by default\n");
1359 fprintf( stderr, " -T n = use n delivery threads (5 bu default)\n" );
1360 fprintf( stderr, " -m mcast = allow remotes on multicast address\n" );
1361 fprintf( stderr, " -t tap = use the nominated tap (or - for stdio)\n" );
1362 fprintf( stderr, " -I source = use given source address for UDP\n" );
1366 // Open the given tap
1367 static int tun_alloc(char *dev, int flags) {
1370 if ( ( fd = open( "/dev/net/tun", O_RDWR ) ) < 0 ) {
1371 perror( "Opening /dev/net/tun" );
1374 memset( &ifr, 0, sizeof( ifr ) );
1375 ifr.ifr_flags = flags;
1377 strcpy( ifr.ifr_name, dev );
1379 if ( ( err = ioctl( fd, TUNSETIFF, (void *) &ifr ) ) < 0 ) {
1380 perror( "ioctl(TUNSETIFF)" );
1384 strcpy( dev, ifr.ifr_name );
1388 // Handle packet received on the tap/stdio channel
1389 static void initialize_tap() {
1390 // Ensure there is a Remote for this
1391 static struct Remote *tap_remote = 0;
1392 if ( tap_remote == 0 ) {
1394 if ( tap_remote == 0 ) {
1395 tap_remote = add_remote( 0, 0 );
1401 // Thread to handle tap/stdio input
1402 static void *doreadTap(void *data) {
1403 int fd = ((ReaderData*) data)->fd;
1404 unsigned int end = 0; // Packet size
1405 unsigned int cur = 0; // Amount read so far
1407 PacketItem *todo = (PacketItem*) Queue_getItem( &todolist.free );
1411 int n = read_into( 0, (unsigned char *) &plength,
1412 sizeof( plength ), 0 );
1414 // Tap/stdio closed => exit silently
1417 end = ntohs( plength );
1419 while ( ( e = ( end - cur ) ) != 0 ) {
1420 unsigned char *p = todo->buffer + cur;
1421 if ( end > BUFSIZE ) {
1422 // Oversize packets should be read and discarded
1423 if ( e > BUFSIZE ) {
1428 cur += read_into( 0, p, e, 1 );
1431 end = doread( fd, todo->buffer, BUFSIZE );
1434 VERBOSE3OUT( "TAP/stdio input %d bytes\n", end );
1435 if ( end <= BUFSIZE ) {
1438 Queue_addItem( &todolist.full, (QueueItem*) todo );
1439 todo = (PacketItem*) Queue_getItem( &todolist.free );
1446 // Application main function
1447 // Parentheses mark optional
1448 // $* = (-v) (-4) (-B n) (-T n) (-m mcast) (-t port) (ip:)port (remote)+
1449 // remote = ipv4(/maskwidth)(:port)(=key)
1450 // remote = ipv6(/maskwidth)(=key)
1451 // remote = [ipv6(/maskwidth)](:port)(=key)
1452 // ip = ipv4 | [ipv6]
1453 int main(int argc, char *argv[]) {
1454 pthread_t thread; // Temporary thread id
1456 progname = (unsigned char *) argv[0];
1457 ///// Parse command line arguments
1459 #define ENSUREARGS(n) if ( argc < i + n ) usage()
1461 // First: optional -v, -vv or -vvv
1462 if ( strncmp( "-v", argv[i], 2 ) == 0 ) {
1463 if ( strncmp( "-v", argv[i], 3 ) == 0 ) {
1465 } else if ( strncmp( "-vv", argv[i], 4 ) == 0 ) {
1467 } else if ( strncmp( "-vvv", argv[i], 5 ) == 0 ) {
1475 if ( strncmp( "-tpg", argv[i], 4 ) == 0 ) {
1480 // then: optional -4
1481 if ( strncmp( "-4", argv[i], 2 ) == 0 ) {
1486 // then: optional -B buffers
1487 if ( strncmp( "-B", argv[i], 2 ) == 0 ) {
1489 if ( parse_buffers_count( argv[i+1] ) ) {
1495 // then: optional -T threads
1496 if ( strncmp( "-T", argv[i], 2 ) == 0 ) {
1498 if ( parse_threads_count( argv[i+1] ) ) {
1504 // then: optional -m mcast
1505 if ( strncmp( "-m", argv[i], 2 ) == 0 ) {
1507 if ( parse_mcast( argv[i+1] ) ) {
1513 // then: optional -t tap
1514 if ( strncmp( "-t", argv[i], 2 ) == 0 ) {
1520 // Then optional source address for UDP
1521 if ( strncmp( "-I", argv[i], 2 ) == 0 ) {
1523 if ( parse_udp_source( argv[i+1] ) ) {
1529 // then: required port
1530 if ( sscanf( argv[i++], "%d", &port ) != 1 ) {
1531 fprintf( stderr, "Bad local port: %s\n", argv[i-1] );
1534 // then: any number of allowed remotes
1535 struct Allowed *last_allowed = 0;
1536 for ( ; i < argc; i++ ) {
1537 if ( last_allowed ) {
1538 // optionally adding ignored interfaces
1539 if ( strncmp( "-i", argv[i], 2 ) == 0 ) {
1541 if ( parse_ignored_interfaces( argv[i+1], last_allowed ) ) {
1548 if ( ( last_allowed = add_allowed( argv[i] ) ) == 0 ) {
1549 fprintf( stderr, "Cannot load remote %s. Exiting.\n", argv[i] );
1553 // end of command line parsing
1555 // Initialize buffers and threads
1556 if ( threads_count == 0 ) {
1559 if ( buffers_count < threads_count ) {
1560 buffers_count = 2 * threads_count;
1562 todolist_initialize( buffers_count, threads_count );
1564 // Set up the tap/stdio channel
1566 // set up the nominated tap
1567 if ( strcmp( "-", tap ) ) { // Unless "-"
1568 tap_fd = tun_alloc( tap, IFF_TAP | IFF_NO_PI );
1570 fprintf( stderr, "Error connecting to interface %s!\n", tap);
1573 VERBOSEOUT( "Using tap %s at %d\n", tap, tap_fd );
1575 // pretend a zero packet on the tap, for initializing.
1578 // set up for stdin/stdout local traffix
1579 setbuf( stdout, NULL ); // No buffering on stdout.
1580 tap_fd = 0; // actually stdin
1586 // Set up the multicast UDP channel (all interfaces)
1587 if ( mcast.group.imr_multiaddr.s_addr ) {
1589 unsigned char *x = (unsigned char *) &mcast.group.imr_multiaddr.s_addr;
1590 VERBOSEOUT( "Using multicast %s:%d at %d\n",
1591 inet_nmtoa( x, 4 ), ntohs( mcast.sock.in4.sin_port ),
1594 // Set up the unicast UPD channel (all interfaces)
1596 // set up ipv4 socket
1597 if ( ( udp_fd = socket( AF_INET, SOCK_DGRAM, 0 ) ) == 0 ) {
1598 perror( "creating socket");
1601 struct sockaddr_in udp_addr = {
1602 .sin_family = AF_INET,
1603 .sin_port = htons( port ),
1605 if ( udp_source.family == 0 ) {
1606 udp_addr.sin_addr.s_addr = htonl( INADDR_ANY );
1608 udp_addr.sin_addr.s_addr = *((uint32_t*) udp_source.address);
1610 if ( bind( udp_fd, (struct sockaddr*) &udp_addr, sizeof(udp_addr))) {
1611 fprintf( stderr, "Error binding socket!\n");
1614 VERBOSEOUT( "Using ipv4 UDP at %d\n", udp_fd );
1616 // set up ipv6 socket
1617 if ( ( udp_fd = socket( AF_INET6, SOCK_DGRAM, 0 ) ) == 0 ) {
1618 perror( "creating socket");
1621 struct sockaddr_in6 udp6_addr = {
1622 .sin6_family = AF_INET6,
1623 .sin6_port = htons( port ),
1625 memcpy( udp6_addr.sin6_addr.s6_addr, udp_source.address, 16 );
1626 if ( bind( udp_fd, (struct sockaddr*) &udp6_addr, sizeof(udp6_addr))) {
1627 fprintf( stderr, "Error binding socket!\n");
1630 VERBOSEOUT( "Using ipv6 UDP at %d\n", udp_fd );
1632 // If not using stdio for local traffic, then stdin and stdout are
1633 // closed here, so as to avoid that any other traffic channel gets
1634 // 0 or 1 as its file descriptor. Note: stderr (2) is left open.
1639 VERBOSE2OUT( "Socket loop tap=%d mcast=%d udp=%d\n",
1640 tap_fd, mcast.fd, udp_fd );
1643 ReaderData udp_reader = { .fd = udp_fd };
1644 pthread_create( &thread, 0, doreadUDP, &udp_reader );
1646 if ( mcast.group.imr_multiaddr.s_addr ) {
1647 ReaderData mcast_reader = { .fd = mcast.fd };
1648 pthread_create( &thread, 0, doreadUDP, &mcast_reader );
1651 if ( tap_fd || stdio ) {
1652 ReaderData tap_reader = { .fd = tap_fd };
1653 pthread_create( &thread, 0, doreadTap, &tap_reader );
1656 // Start heartbeating to uplinks
1659 heartbeat( udp_fd );