2 * $Source: /cvs/cvsroot/d2x/arch/linux_ipx_udp.c,v $
5 * $Date: 2001-01-29 13:35:08 $
7 * IPX driver for native Linux TCP/IP networking (UDP implementation)
9 * Contact Jan [Lace] Kratochvil <short@ucw.cz> for assistance
10 * (no "It somehow doesn't work! What should I do?" complaints, please)
11 * Special thanks to Vojtech Pavlik <vojtech@ucw.cz> for testing.
13 * Also you may see KIX - KIX kix out KaliNix (in Linux-Linux only):
14 * http://atrey.karlin.mff.cuni.cz/~short/sw/kix.c.gz
16 * Primarily based on ipx_kali.c - "IPX driver for KaliNix interface"
17 * which is probably mostly by Jay Cotton <jay@kali.net>.
18 * Parts shamelessly stolen from my KIX v0.99.2 and GGN v0.100
22 * 0.99.1 - now the default broadcast list also contains all point-to-point
23 * links with their destination peer addresses
24 * 0.99.2 - commented a bit :-)
25 * - now adds to broadcast list each host it gets some packet from
26 * which is already not covered by local physical ethernet broadcast
27 * - implemented short-signature packet format
28 * - compatibility mode for old D1X releases due to the previous bullet
32 * No network server software is needed, neither KIX nor KaliNIX.
34 * Add command line argument "-udp". In default operation D1X will send
35 * broadcasts too all the local interfaces found. But you may also use
36 * additional parameter specified after "-udp" to modify the default
37 * broadcasting style and UDP port numbers binding:
39 * ./d1x -udp [@SHIFT]=HOST_LIST Broadcast ONLY to HOST_LIST
40 * ./d1x -udp [@SHIFT]+HOST_LIST Broadcast both to local ifaces & to HOST_LIST
42 * HOST_LIST is a comma (',') separated list of HOSTs:
43 * HOST is an IPv4 address (so-called quad like 192.168.1.2) or regular hostname
44 * HOST can also be in form 'address:SHIFT'
45 * SHIFT sets the UDP port base offset (e.g. +2), can be used to run multiple
46 * clients on one host simultaneously. This SHIFT has nothing to do
47 * with the dynamic-sockets (PgUP/PgDOWN) option in Descent, it's another
48 * higher-level differentiation option.
53 * - Run D1X to participate in normal local network (Linux only, of course)
55 * ./d1x -udp @1=localhost:2 & ./d1x -udp @2=localhost:1
56 * - Run two clients simultaneously fighting each other (only each other)
58 * ./d1x -udp =192.168.4.255
59 * - Run distant Descent which will participate with remote network
60 * 192.168.4.0 with netmask 255.255.255.0 (broadcast has 192.168.4.255)
61 * - You'll have to also setup hosts in that network accordingly:
62 * ./d1x -udp +UPPER_DISTANT_MACHINE_NAME
66 * $Log: not supported by cvs2svn $
75 #include <netinet/in.h> /* for htons & co. */
81 #include <sys/ioctl.h>
87 extern unsigned char ipx_MyAddress[10];
91 #define UDP_BASEPORT 28342
92 #define PORTSHIFT_TOLERANCE 0x100
93 #define MAX_PACKETSIZE 8192
95 /* Packet format: first is the signature { 0xD1,'X' } which can be also
96 * { 'D','1','X','u','d','p'} for old-fashioned packets.
97 * Then follows virtual socket number (as changed during PgDOWN/PgUP)
98 * in network-byte-order as 2 bytes (u_short). After such 4/8 byte header
99 * follows raw data as communicated with D1X network core functions.
102 // Length HAS TO BE 6!
103 #define D1Xudp "D1Xudp"
104 // Length HAS TO BE 2!
105 #define D1Xid "\xD1X"
107 static int open_sockets = 0;
108 static int dynamic_socket = 0x401;
109 static const int val_one=1;
111 /* OUR port. Can be changed by "@X[+=]..." argument (X is the shift value)
114 static int baseport=UDP_BASEPORT;
116 /* Have we some old D1X in network and have we to maintain compatibility?
117 * FIXME: Following scenario is braindead:
118 * A (NEW) , B (OLD) , C (NEW)
119 * host A) We start new D1X. A-newcomm, B-none , C-none
120 * host B) We start OLD D1X. A-newcomm, B-oldcomm, C-none
121 * Now host A hears host B and switches: A-oldcomm, B-oldcomm, C-none
122 * host C) We start new D1X. A-oldcomm, B-oldcomm, C-newcomm
123 * Now host C hears host A/B and switches: A-oldcomm, B-oldcomm, C-oldcomm
124 * Now host B finishes: A-oldcomm, B-none , C-oldcomm
126 * But right now we have hosts A and C, both new code equipped but
127 * communicating wastefully by the OLD protocol! Bummer.
130 static char compatibility=0;
132 static int have_empty_address() {
134 for (i = 0; i < 10 && !ipx_MyAddress[i]; i++) ;
138 #define MSGHDR "IPX_udp: "
140 static void msg(const char *fmt,...)
143 fputs(MSGHDR,stdout);
150 static void chk(void *p)
153 msg("FATAL: Virtual memory exhausted!");
157 #define FAIL(m...) do { msg(#m); return -1; } while (0)
159 /* Find as much as MAX_BRDINTERFACES during local iface autoconfiguration.
160 * Note that more interfaces can be added during manual configuration
161 * or host-received-packet autoconfiguration
164 #define MAX_BRDINTERFACES 16
166 /* We require the interface to be UP and RUNNING to accept it.
169 #define IF_REQFLAGS (IFF_UP|IFF_RUNNING)
171 /* We reject any interfaces declared as LOOPBACK type.
173 #define IF_NOTFLAGS (IFF_LOOPBACK)
175 static struct sockaddr_in *broads,broadmasks[MAX_BRDINTERFACES];
176 static int broadnum,masksnum,broadsize;
178 /* We'll check whether the "broads" array of destination addresses is now
179 * full and so needs expanding.
182 static void chkbroadsize(void)
184 if (broadnum<broadsize) return;
185 broadsize=broadsize?broadsize*2:8;
186 chk(broads=realloc(broads,sizeof(*broads)*broadsize));
189 /* This function is called during init and has to grab all system interfaces
190 * and collect their broadcast-destination addresses (and their netmasks).
191 * Typically it founds only one ethernet card and so returns address in
192 * the style "192.168.1.255" with netmask "255.255.255.0".
193 * Broadcast addresses are filled into "broads", netmasks to "broadmasks".
196 /* Stolen from my GGN */
197 static int addiflist(void)
199 unsigned cnt=MAX_BRDINTERFACES,i,j;
200 struct ifconf ifconf;
202 struct sockaddr_in *sinp,*sinmp;
205 if ((sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP))<0)
206 FAIL("Creating socket() failure during broadcast detection: %m");
209 if (ioctl(sock,SIOCGIFCOUNT,&cnt))
210 { /* msg("Getting iterface count error: %m"); */ }
215 chk(ifconf.ifc_req=alloca((ifconf.ifc_len=cnt*sizeof(struct ifreq))));
216 if (ioctl(sock,SIOCGIFCONF,&ifconf)||ifconf.ifc_len%sizeof(struct ifreq)) {
218 FAIL("ioctl(SIOCGIFCONF) failure during broadcast detection: %m");
220 cnt=ifconf.ifc_len/sizeof(struct ifreq);
221 chk(broads=malloc(cnt*sizeof(*broads)));
223 for (i=j=0;i<cnt;i++) {
224 if (ioctl(sock,SIOCGIFFLAGS,ifconf.ifc_req+i)) {
226 FAIL("ioctl(udp,\"%s\",SIOCGIFFLAGS) error: %m",ifconf.ifc_req[i].ifr_name);
228 if (((ifconf.ifc_req[i].ifr_flags&IF_REQFLAGS)!=IF_REQFLAGS)||
229 (ifconf.ifc_req[i].ifr_flags&IF_NOTFLAGS))
231 if (ioctl(sock,(ifconf.ifc_req[i].ifr_flags&IFF_BROADCAST?SIOCGIFBRDADDR:SIOCGIFDSTADDR),ifconf.ifc_req+i)) {
233 FAIL("ioctl(udp,\"%s\",SIOCGIF{DST/BRD}ADDR) error: %m",ifconf.ifc_req[i].ifr_name);
236 sinp =(struct sockaddr_in *)&ifconf.ifc_req[i].ifr_broadaddr;
237 sinmp=(struct sockaddr_in *)&ifconf.ifc_req[i].ifr_netmask ;
238 if (sinp->sin_family!=AF_INET || sinmp->sin_family!=AF_INET) continue;
240 broads[j].sin_port=UDP_BASEPORT; //FIXME: No possibility to override from cmdline
241 broadmasks[j]=*sinmp;
249 #define addreq(a,b) ((a).sin_port==(b).sin_port&&(a).sin_addr.s_addr==(b).sin_addr.s_addr)
251 /* Previous function addiflist() can (and probably will) report multiple
252 * same addresses. On some Linux boxes is present both device "eth0" and
253 * "dummy0" with the same IP addreesses - we'll filter it here.
256 static void unifyiflist(void)
260 for (s=0;s<broadnum;s++) {
262 if (addreq(broads[s],broads[i])) break;
263 if (i>=s) broads[d++]=broads[s];
268 static unsigned char qhbuf[6];
270 /* Parse PORTSHIFT numeric parameter
273 static void portshift(const char *cs)
276 unsigned short ports=0;
279 if (port<-PORTSHIFT_TOLERANCE || port>+PORTSHIFT_TOLERANCE)
280 msg("Invalid portshift in \"%s\", tolerance is +/-%d",cs,PORTSHIFT_TOLERANCE);
281 else ports=htons(port);
282 memcpy(qhbuf+4,&ports,2);
285 /* Do hostname resolve on name "buf" and return the address in buffer "qhbuf".
287 static unsigned char *queryhost(char *buf)
293 if ((s=strrchr(buf,':'))) {
298 else memset(qhbuf+4,0,2);
299 he=gethostbyname((char *)buf);
302 msg("Error resolving my hostname \"%s\"",buf);
305 if (he->h_addrtype!=AF_INET || he->h_length!=4) {
306 msg("Error parsing resolved my hostname \"%s\"",buf);
309 if (!*he->h_addr_list) {
310 msg("My resolved hostname \"%s\" address list empty",buf);
313 memcpy(qhbuf,(*he->h_addr_list),4);
317 /* Dump raw form of IP address/port by fancy output to user
319 static void dumpraddr(unsigned char *a)
322 printf("[%u.%u.%u.%u]",a[0],a[1],a[2],a[3]);
323 port=(signed short)ntohs(*(unsigned short *)(a+4));
324 if (port) printf(":%+d",port);
327 /* Like dumpraddr() but for structure "sockaddr_in"
330 static void dumpaddr(struct sockaddr_in *sin)
332 unsigned short ports;
334 memcpy(qhbuf+0,&sin->sin_addr,4);
335 ports=htons(((short)ntohs(sin->sin_port))-UDP_BASEPORT);
336 memcpy(qhbuf+4,&ports,2);
340 /* Startup... Uninteresting parsing...
343 static int ipx_udp_GetMyAddress(void) {
349 if (!have_empty_address())
352 if (!((i=FindArg("-udp")) && (s=Args[i+1]) && (*s=='=' || *s=='+' || *s=='@'))) s=NULL;
354 if (gethostname(buf,sizeof(buf))) FAIL("Error getting my hostname");
355 if (!(queryhost(buf))) FAIL("Querying my own hostname \"%s\"",buf);
357 if (s) while (*s=='@') {
359 while (isdigit(*s)) s++;
362 memset(ipx_MyAddress+0,0,4);
363 memcpy(ipx_MyAddress+4,qhbuf,6);
364 baseport+=(short)ntohs(*(unsigned short *)(qhbuf+4));
366 if (!s || (s && !*s)) addiflist();
368 if (*s=='+') addiflist();
371 struct sockaddr_in *sin;
372 while (isspace(*s)) s++;
374 for (s2=s;*s2 && *s2!=',';s2++);
375 chk(ns=malloc(s2-s+1));
378 if (!queryhost(ns)) msg("Ignored broadcast-destination \"%s\" as being invalid",ns);
381 sin=broads+(broadnum++);
382 sin->sin_family=AF_INET;
383 memcpy(&sin->sin_addr,qhbuf+0,4);
384 sin->sin_port=htons(((short)ntohs(*(unsigned short *)(qhbuf+4)))+UDP_BASEPORT);
391 printf(MSGHDR "Using TCP/IP address ");
392 dumpraddr(ipx_MyAddress+4);
395 printf(MSGHDR "Using %u broadcast-dest%s:",broadnum,(broadnum==1?"":"s"));
396 for (i=0;i<broadnum;i++) {
406 /* We should probably avoid such insanity here as during PgUP/PgDOWN
407 * (virtual port number change) we wastefully destroy/create the same
408 * socket here (binded always to "baseport"). FIXME.
409 * "open_sockets" can be only 0 or 1 anyway.
412 static int ipx_udp_OpenSocket(ipx_socket_t *sk, int port) {
413 struct sockaddr_in sin;
416 if (have_empty_address())
417 if (ipx_udp_GetMyAddress() < 0) FAIL("Error getting my address");
419 msg("OpenSocket on D1X socket port %d",port);
422 port = dynamic_socket++;
424 if ((sk->fd = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP)) < 0) {
426 FAIL("socket() creation failed on port %d: %m",port);
428 if (setsockopt(sk->fd,SOL_SOCKET,SO_BROADCAST,&val_one,sizeof(val_one))) {
429 if (close(sk->fd)) msg("close() failed during error recovery: %m");
431 FAIL("setsockopt(SO_BROADCAST) failed: %m");
433 sin.sin_family=AF_INET;
434 sin.sin_addr.s_addr=htonl(INADDR_ANY);
435 sin.sin_port=htons(baseport);
436 if (bind(sk->fd,(struct sockaddr *)&sin,sizeof(sin))) {
437 if (close(sk->fd)) msg("close() failed during error recovery: %m");
439 FAIL("bind() to UDP port %d failed: %m",baseport);
447 /* The same comment as in previous "ipx_udp_OpenSocket"...
450 static void ipx_udp_CloseSocket(ipx_socket_t *mysock) {
452 msg("close w/o open");
455 msg("CloseSocket on D1X socket port %d",mysock->socket);
456 if (close(mysock->fd))
457 msg("close() failed on CloseSocket D1X socket port %d: %m",mysock->socket);
459 if (--open_sockets) {
460 msg("(closesocket) %d sockets left", open_sockets);
465 /* Here we'll send the packet to our host. If it is unicast packet, send
466 * it to IP address/port as retrieved from IPX address. Otherwise (broadcast)
467 * we'll repeat the same data to each host in our broadcasting list.
470 static int ipx_udp_SendPacket(ipx_socket_t *mysock, IPXPacket_t *IPXHeader,
471 u_char *data, int dataLen) {
472 struct sockaddr_in toaddr,*dest;
478 msg("SendPacket enter, dataLen=%d",dataLen);
480 if (dataLen<0 || dataLen>MAX_PACKETSIZE) return -1;
481 chk(buf=alloca(8+dataLen));
482 if (compatibility) memcpy(buf+0,D1Xudp,6),buf+=6;
483 else memcpy(buf+0,D1Xid ,2),buf+=2;
484 memcpy(buf+0,IPXHeader->Destination.Socket,2);
485 memcpy(buf+2,data,dataLen);
487 toaddr.sin_family=AF_INET;
488 memcpy(&toaddr.sin_addr,IPXHeader->Destination.Node+0,4);
489 toaddr.sin_port=htons(((short)ntohs(*(unsigned short *)(IPXHeader->Destination.Node+4)))+UDP_BASEPORT);
491 for (bcast=(toaddr.sin_addr.s_addr==htonl(INADDR_BROADCAST)?0:-1);bcast<broadnum;bcast++) {
492 if (bcast>=0) dest=broads+bcast;
496 printf(MSGHDR "sendto((%d),Node=[4] %02X %02X,Socket=%02X %02X,s_port=%u,",
498 IPXHeader->Destination.Node [4],IPXHeader->Destination.Node [5],
499 IPXHeader->Destination.Socket[0],IPXHeader->Destination.Socket[1],
500 ntohs(dest->sin_port));
504 i=sendto(mysock->fd,buf-(compatibility?6:2),(compatibility?8:4)+dataLen,
505 0,(struct sockaddr *)dest,sizeof(*dest));
506 if (bcast==-1) return (i<8?-1:i-8);
511 /* Here we will receive new packet to the given buffer. Both formats of packets
512 * are supported, we fallback to old format when first obsolete packet is seen.
513 * If the (valid) packet is received from unknown host, we will add it to our
514 * broadcasting list. FIXME: For now such autoconfigured hosts are NEVER removed.
517 static int ipx_udp_ReceivePacket(ipx_socket_t *s, char *outbuf, int outbufsize,
518 struct ipx_recv_data *rd) {
520 struct sockaddr_in fromaddr;
521 int fromaddrsize=sizeof(fromaddr);
522 unsigned short ports;
526 if ((size=recvfrom(s->fd,outbuf,outbufsize,0,(struct sockaddr *)&fromaddr,&fromaddrsize))<0)
529 printf(MSGHDR "recvfrom((%d-8=%d),",size,size-8);
533 if (fromaddr.sin_family!=AF_INET) return -1;
534 if (size<4) return -1;
535 if (memcmp(outbuf+0,D1Xid,2)) {
536 if (size<8 || memcmp(outbuf+0,D1Xudp,6)) return -1;
537 if (!compatibility) {
539 fputs(MSGHDR "Received obsolete packet from ",stdout);
541 puts(", upgrade that machine.\n" MSGHDR "Turning on compatibility mode...");
547 /* Lace: (dst_socket & src_socket) should be network-byte-order by comment in include/ipx_drv.h */
548 /* This behaviour presented here is broken. It is not used anywhere, so why bother? */
549 rd->src_socket = ntohs(*(unsigned short *)(outbuf+offs));
550 if (rd->src_socket != s->socket) {
552 msg(" - pkt was dropped (dst=%d,my=%d)",rd->src_socket,s->socket);
556 rd->dst_socket = s->socket;
558 for (i=0;i<broadnum;i++) {
560 if (addreq(fromaddr,broads[i])) break;
563 if (fromaddr.sin_port==broads[i].sin_port
564 &&( fromaddr.sin_addr.s_addr & broadmasks[i].sin_addr.s_addr)
565 ==(broads[i].sin_addr.s_addr & broadmasks[i].sin_addr.s_addr)) break;
570 broads[broadnum++]=fromaddr;
571 fputs(MSGHDR "Adding host ",stdout);
573 puts(" to broadcasting address list");
576 memmove(outbuf,outbuf+offs+2,size-(offs+2));
579 memcpy(rd->src_node+0,&fromaddr.sin_addr,4);
580 ports=htons(ntohs(fromaddr.sin_port)-UDP_BASEPORT);
581 memcpy(rd->src_node+4,&ports,2);
582 memset(rd->src_network, 0, 4);
585 printf(MSGHDR "ReceivePacket: size=%d,from=",size);
586 dumpraddr(rd->src_node);
593 struct ipx_driver ipx_udp = {
594 ipx_udp_GetMyAddress,
598 ipx_udp_ReceivePacket,
599 ipx_general_PacketReady