#include <u.h>#include <libc.h>#include <bio.h>#include <ip.h>#include <ndb.h>#include "/sys/src/9/port/arp.h"#include "bootp.h" int 	dbg;int	bootreq;int	bootctl;char	*sysname;Ipinfo	myiip;Ndb	*db;char	blog[] = "ipboot"; typedef struct Boottab Boottab;struct Boottab{	Ipinfo;	uchar	reply[4];		/* reply address */}; void		openlisten(void);void		fatal(int, char*, ...);void		warning(int, char*, ...);void		doreply(Bootp*, Boottab*);Boottab*	lookup(Bootp*); voidmain(int argc, char **argv){	Bootp *boot;	Boottab *f;	char buf[1024];	uchar myip[4]; 	ARGBEGIN{	case 'd':		dbg++;		break;	default:		fprint(2, "usage: bootp [-d]\n");		exits("usage");	}ARGEND	USED(argc); USED(argv); 	fmtinstall('E', eipconv);	fmtinstall('I', eipconv); 	/* who am i? */	sysname = getenv("sysname");	if(sysname == 0)		fatal(0, "I must know my name!");	if(myipaddr(myip, "/net/udp") < 0)		fatal(0, "I must know my ip addr!"); 	/* get local info from the database */	db = ndbopen(0);	if(db == 0)		fatal(0, "can't open database\n");	sprint(buf, "%I", myip);	if(ipinfo(db, 0, buf, 0, &myiip) < 0)		fatal(0, "I'm not in network database!"); 	syslog(dbg, blog, "started"); 	switch(rfork(RFNOTEG|RFPROC|RFFDG)) {	case -1:		fatal(1, "fork");	case 0:		break;	default:		exits(0);	} 	openlisten(); 	for(;;) {		read(bootreq, buf, sizeof(buf));		boot = (Bootp*)buf;		if(boot->op != Bootrequest)			continue;		if(boot->htype != 1){			syslog(dbg, blog, "not ethernet %E\n", boot->chaddr);			continue;		} 		/*		 *  Answer the request if the client didn't specify another		 *  server and either we know the bootfile or the client		 *  specified one.		 */		if(boot->sname[0]==0 || strcmp(boot->sname, sysname)==0){			f = lookup(boot);			if(f && (f->bootf[0] || boot->file[0]!=0)){				doreply(boot, f);			} else {				if(f)					syslog(dbg, blog, "no bootfile for %I %E",						f->ipaddr, f->etheraddr);				else					syslog(dbg, blog, "no entry for %I %E",						boot->ciaddr, boot->chaddr); 			}		}	}} /* *  lookup info about a client in the database.  The client may have supplied *  an hardware address or an ip adress and a hardware address. */Boottab*lookup(Bootp *b){	static Boottab bt;	char ether[32];	char ip[32]; 	memset(&bt, 0, sizeof(Boottab)); 	sprint(ether, "%E", b->chaddr);	sprint(ip, "%I", b->ciaddr);	if(ipinfo(db, ether , *ip ? ip : 0, 0, &bt) < 0)		return 0;  	/* it knows who it it, reply directly */	memmove(bt.reply, bt.ipaddr, sizeof(bt.reply)); 	return &bt;} voidarpenter(uchar *ip, uchar *ether){	Arpentry a;	int f; 	memmove(a.etaddr, ether, sizeof(a.etaddr));	memmove(a.ipaddr, ip, sizeof(a.ipaddr)); 	f = open("#a/arp/data", OWRITE);	if(f < 0) {		syslog(dbg, blog, "open arp: %r\n");		return;	}	if(write(f, &a, sizeof(a)) < 0)		syslog(dbg, blog, "write arp: %r\n");	close(f);} voiddoreply(Bootp *boot, Boottab *tab){	Bootp reply;	char buf[128];	int n; 	boot->sname[sizeof(boot->sname)-1] = '\0'; 	memmove(&reply, boot, sizeof(reply));	reply.op = Bootreply; 	/* the client always best know his ether address */	if(tab)		arpenter(tab->ipaddr, boot->chaddr); 	else		arpenter(boot->ciaddr, boot->chaddr); 	/* but we best know the ip addresses */	if(tab)		memmove(reply.yiaddr, tab->ipaddr, sizeof(tab->ipaddr));	else		memmove(reply.yiaddr, boot->ciaddr, sizeof(reply.yiaddr));	memmove(reply.siaddr, myiip.ipaddr, sizeof(myiip.ipaddr));	if(tab)		memmove(reply.giaddr, tab->gwip, sizeof(reply.giaddr));	else		memset(reply.giaddr, 0, sizeof(reply.giaddr)); 	strcpy(reply.sname, sysname);	if(boot->file[0] != '\0') {		if(boot->file[0] != '/')			sprint(reply.file, "/lib/tftpd/%s", boot->file);	}	else if(tab)		strcpy(reply.file, tab->bootf);	else		strcpy(reply.file, "no file"); 	if(tab && strncmp(reply.vend, "p9  ", 4) == 0)		sprint(reply.vend, "p9  %I %I %I %I", tab->ipmask, tab->fsip,			tab->auip, tab->gwip); 	syslog(dbg, blog, "reply to %I %E %s %s", reply.yiaddr, boot->chaddr,		reply.file, reply.vend); 	/*	 *  get a connection (sort of) back to the client	 */	if(tab)		sprint(buf, "connect %I!68", tab->reply);	else		sprint(buf, "connect %I!68", reply.yiaddr);	if(write(bootctl, buf, strlen(buf)) < 0){		warning(1, "can't %s", buf);		return;	} 	/*	 *  send the reply	 */	n = write(bootreq, (void*)&reply, sizeof(reply));	if(n < 0)		warning(1, "can't reply to %s", buf); 	/*	 *  clear	 */	sprint(buf, "connect 0.0.0.0!0");	if(write(bootctl, buf, strlen(buf)) < 0){		warning(1, "can't %s", buf);		return;	}} voidopenlisten(void){	char data[128];	char devdir[40]; 	bootctl = announce("udp!*!bootp", devdir);	if(bootctl < 0)		fatal(1, "can't announce"); 	sprint(data, "%s/data", devdir); 	bootreq = open(data, ORDWR);	if(bootreq < 0)		fatal(1, "open udp data");} voidfatal(int syserr, char *fmt, ...){	char buf[ERRLEN], sysbuf[ERRLEN]; 	doprint(buf, buf+sizeof(buf), fmt, (&fmt+1));	if(syserr) {		errstr(sysbuf);		fprint(2, "bootp: %s: %s\n", buf, sysbuf);	}	else		fprint(2, "bootp: %s\n", buf);	exits(buf);} voidwarning(int syserr, char *fmt, ...){	char buf[ERRLEN], sysbuf[ERRLEN]; 	doprint(buf, buf+sizeof(buf), fmt, (&fmt+1));	if(syserr) {		errstr(sysbuf);		fprint(2, "bootp: %s: %s\n", buf, sysbuf);	}	else		fprint(2, "bootp: %s\n", buf);}