#include "u.h"#include "lib.h"#include "mem.h"#include "dat.h"#include "fns.h"#include "io.h" #include "ip.h" enum {	CHECKSUM = 1,	/* set zero if trouble booting from Linux */}; uchar broadcast[Eaddrlen] = {	0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,}; static ushort tftpport = 5000;static int Id = 1;static Netaddr myaddr;static Netaddr server; typedef struct {	uchar	header[4];	uchar	data[Segsize];} Tftp;static Tftp tftpb; static voidhnputs(uchar *ptr, ushort val){	ptr[0] = val>>8;	ptr[1] = val;} static voidhnputl(uchar *ptr, ulong val){	ptr[0] = val>>24;	ptr[1] = val>>16;	ptr[2] = val>>8;	ptr[3] = val;} static ulongnhgetl(uchar *ptr){	return ((ptr[0]<<24) | (ptr[1]<<16) | (ptr[2]<<8) | ptr[3]);} static ushortnhgets(uchar *ptr){	return ((ptr[0]<<8) | ptr[1]);} static	short	endian	= 1;static	char*	aendian	= (char*)&endian;#define	LITTLE	*aendian static ushortptcl_csum(void *a, int len){	uchar *addr;	ulong t1, t2;	ulong losum, hisum, mdsum, x; 	addr = a;	losum = 0;	hisum = 0;	mdsum = 0; 	x = 0;	if((ulong)addr & 1) {		if(len) {			hisum += addr[0];			len--;			addr++;		}		x = 1;	}	while(len >= 16) {		t1 = *(ushort*)(addr+0);		t2 = *(ushort*)(addr+2);	mdsum += t1;		t1 = *(ushort*)(addr+4);	mdsum += t2;		t2 = *(ushort*)(addr+6);	mdsum += t1;		t1 = *(ushort*)(addr+8);	mdsum += t2;		t2 = *(ushort*)(addr+10);	mdsum += t1;		t1 = *(ushort*)(addr+12);	mdsum += t2;		t2 = *(ushort*)(addr+14);	mdsum += t1;		mdsum += t2;		len -= 16;		addr += 16;	}	while(len >= 2) {		mdsum += *(ushort*)addr;		len -= 2;		addr += 2;	}	if(x) {		if(len)			losum += addr[0];		if(LITTLE)			losum += mdsum;		else			hisum += mdsum;	} else {		if(len)			hisum += addr[0];		if(LITTLE)			hisum += mdsum;		else			losum += mdsum;	} 	losum += hisum >> 8;	losum += (hisum & 0xff) << 8;	while(hisum = losum>>16)		losum = hisum + (losum & 0xffff); 	return ~losum;} static ushortip_csum(uchar *addr){	int len;	ulong sum = 0; 	len = (addr[0]&0xf)<<2; 	while(len > 0) {		sum += addr[0]<<8 | addr[1] ;		len -= 2;		addr += 2;	} 	sum = (sum & 0xffff) + (sum >> 16);	sum = (sum & 0xffff) + (sum >> 16);	return (sum^0xffff);} static voidudpsend(int ctlrno, Netaddr *a, void *data, int dlen){	Udphdr *uh;	Etherhdr *ip;	static Etherpkt pkt;	int len, ptcllen;  	uh = (Udphdr*)&pkt; 	memset(uh, 0, sizeof(Etherpkt));	memmove(uh->udpcksum+sizeof(uh->udpcksum), data, dlen); 	/*	 * UDP portion	 */	ptcllen = dlen + (UDP_HDRSIZE-UDP_PHDRSIZE);	uh->ttl = 0;	uh->udpproto = IP_UDPPROTO;	uh->frag[0] = 0;	uh->frag[1] = 0;	hnputs(uh->udpplen, ptcllen);	hnputl(uh->udpsrc, myaddr.ip);	hnputs(uh->udpsport, myaddr.port);	hnputl(uh->udpdst, a->ip);	hnputs(uh->udpdport, a->port);	hnputs(uh->udplen, ptcllen);	uh->udpcksum[0] = 0;	uh->udpcksum[1] = 0;	/*dlen = (dlen+1)&~1; */	hnputs(uh->udpcksum, ptcl_csum(&uh->ttl, dlen+UDP_HDRSIZE)); 	/*	 * IP portion	 */	ip = (Etherhdr*)&pkt;	len = sizeof(Udphdr)+dlen;	ip->vihl = IP_VER|IP_HLEN;	ip->tos = 0;	ip->ttl = 255;	hnputs(ip->length, len-ETHER_HDR);	hnputs(ip->id, Id++);	ip->frag[0] = 0;	ip->frag[1] = 0;	ip->cksum[0] = 0;	ip->cksum[1] = 0;	hnputs(ip->cksum, ip_csum(&ip->vihl)); 	/*	 * Ethernet MAC portion	 */	hnputs(ip->type, ET_IP);	memmove(ip->d, a->ea, sizeof(ip->d)); 	ethertxpkt(ctlrno, &pkt, len, Timeout);} static voidnak(int ctlrno, Netaddr *a, int code, char *msg, int report){	int n;	char buf[128]; 	buf[0] = 0;	buf[1] = Tftp_ERROR;	buf[2] = 0;	buf[3] = code;	strcpy(buf+4, msg);	n = strlen(msg) + 4 + 1;	udpsend(ctlrno, a, buf, n);	if(report)		print("\ntftp: error(%d): %s\n", code, msg);} static intudprecv(int ctlrno, Netaddr *a, void *data, int dlen){	int n, len;	ushort csm;	Udphdr *h;	ulong addr, timo;	static Etherpkt pkt;	static int rxactive; 	if(rxactive == 0)		timo = 1000;	else		timo = Timeout;	timo += TK2MS(m->ticks);	while(timo > TK2MS(m->ticks)){		n = etherrxpkt(ctlrno, &pkt, timo-TK2MS(m->ticks));		if(n <= 0)			continue; 		h = (Udphdr*)&pkt;		if(nhgets(h->type) != ET_IP)			continue; 		if(ip_csum(&h->vihl)) {			print("ip chksum error\n");			continue;		}		if(h->vihl != (IP_VER|IP_HLEN)) {			print("ip bad vers/hlen\n");			continue;		} 		if(h->udpproto != IP_UDPPROTO)			continue; 		h->ttl = 0;		len = nhgets(h->udplen);		hnputs(h->udpplen, len); 		if(CHECKSUM && nhgets(h->udpcksum)) {			csm = ptcl_csum(&h->ttl, len+UDP_PHDRSIZE);			if(csm != 0) {				print("udp chksum error csum #%4lux len %d\n", csm, n);				break;			}		} 		if(a->port != 0 && nhgets(h->udpsport) != a->port)			continue; 		addr = nhgetl(h->udpsrc);		if(a->ip != Bcastip && addr != a->ip)			continue; 		len -= UDP_HDRSIZE-UDP_PHDRSIZE;		if(len > dlen) {			print("udp: packet too big\n");			continue;		} 		memmove(data, h->udpcksum+sizeof(h->udpcksum), len);		a->ip = addr;		a->port = nhgets(h->udpsport);		memmove(a->ea, pkt.s, sizeof(a->ea)); 		rxactive = 1;		return len;	} 	return 0;} static int tftpblockno; static inttftpopen(int ctlrno, Netaddr *a, char *name, Tftp *tftp){	int i, len, rlen, oport;	char buf[Segsize+2]; 	buf[0] = 0;	buf[1] = Tftp_READ;	len = sprint(buf+2, "%s", name) + 2;	len += sprint(buf+len+1, "octet") + 2; 	oport = a->port;	for(i = 0; i < 5; i++){		a->port = oport;		udpsend(ctlrno, a, buf, len);		a->port = 0;		if((rlen = udprecv(ctlrno, a, tftp, sizeof(Tftp))) < sizeof(tftp->header))			continue; 		switch((tftp->header[0]<<8)|tftp->header[1]){ 		case Tftp_ERROR:			print("tftpopen: error (%d): %s\n",				(tftp->header[2]<<8)|tftp->header[3], tftp->data);			return -1; 		case Tftp_DATA:			tftpblockno = 1;			len = (tftp->header[2]<<8)|tftp->header[3];			if(len != tftpblockno){				print("tftpopen: block error: %d\n", len);				nak(ctlrno, a, 1, "block error", 0);				return -1;			}			return rlen-sizeof(tftp->header);		}	} 	print("tftpopen: failed to connect to server\n");	return -1;} static inttftpread(int ctlrno, Netaddr *a, Tftp *tftp, int dlen){	int blockno, len, retry;	uchar buf[4]; 	buf[0] = 0;	buf[1] = Tftp_ACK;	buf[2] = tftpblockno>>8;	buf[3] = tftpblockno;	tftpblockno++; 	dlen += sizeof(tftp->header); 	retry = 0;buggery:	udpsend(ctlrno, a, buf, sizeof(buf)); 	if((len = udprecv(ctlrno, a, tftp, dlen)) < dlen){		print("tftpread: %d != %d\n", len, dlen);		nak(ctlrno, a, 2, "short read", 0);		if(retry++ < 5)			goto buggery;		return -1;	} 	blockno = (tftp->header[2]<<8)|tftp->header[3];	if(blockno != tftpblockno){		print("?"); 		if(blockno == tftpblockno-1 && retry++ < 8)			goto buggery;		print("tftpread: block error: %d, expected %d\n", blockno, tftpblockno);		nak(ctlrno, a, 1, "block error", 0); 		return -1;	} 	return len-sizeof(tftp->header);} intbootp(int ctlrno, char *file){	Bootp req, rep;	int i, dlen, segsize, text, data, bss, total;	uchar *ea, *addr, *p;	ulong entry;	Exec *exec;	char name[128], *filename, *sysname; 	if((ea = etheraddr(ctlrno)) == 0){		print("invalid ctlrno %d\n", ctlrno);		return -1;	} 	filename = 0;	sysname = 0;	if(file && *file){		strcpy(name, file);		if(filename = strchr(name, ':')){			if(filename != name && *(filename-1) != '\\'){				sysname = name;				*filename++ = 0;			}		}		else			filename = name;	}		 	memset(&req, 0, sizeof(req));	req.op = Bootrequest;	req.htype = 1;			/* ethernet */	req.hlen = Eaddrlen;		/* ethernet */	memmove(req.chaddr, ea, Eaddrlen); 	myaddr.ip = 0;	myaddr.port = BPportsrc;	memmove(myaddr.ea, ea, Eaddrlen); 	for(i = 0; i < 10; i++) {		server.ip = Bcastip;		server.port = BPportdst;		memmove(server.ea, broadcast, sizeof(server.ea));		udpsend(ctlrno, &server, &req, sizeof(req));		if(udprecv(ctlrno, &server, &rep, sizeof(rep)) <= 0)			continue;		if(memcmp(req.chaddr, rep.chaddr, Eaddrlen))			continue;		if(rep.htype != 1 || rep.hlen != Eaddrlen)			continue;		if(sysname == 0 || strcmp(sysname, rep.sname) == 0)			break;	}	if(i >= 10) {		print("bootp timed out\n");		return -1;	} 	if(filename == 0 || *filename == 0)		filename = rep.file; 	if(rep.sname[0] != '\0')		 print("%s ", rep.sname);	print("(%d.%d.%d.%d!%d): %s\n",		rep.siaddr[0],		rep.siaddr[1],		rep.siaddr[2],		rep.siaddr[3],		server.port,		filename);uartwait(); 	myaddr.ip = nhgetl(rep.yiaddr);	myaddr.port = tftpport++;	server.ip = nhgetl(rep.siaddr);	server.port = TFTPport; 	if((dlen = tftpopen(ctlrno, &server, filename, &tftpb)) < 0)		return -1;	exec = (Exec*)(tftpb.data);	if(dlen < sizeof(Exec) || GLLONG(exec->magic) != Q_MAGIC){		nak(ctlrno, &server, 0, "bad magic number", 1);		return -1;	}	text = GLLONG(exec->text);	data = GLLONG(exec->data);	bss = GLLONG(exec->bss);	total = text+data+bss;	entry = GLLONG(exec->entry);print("load@%8.8lux: ", PADDR(entry));uartwait();	print("%d", text); 	addr = (uchar*)PADDR(entry);	p = tftpb.data+sizeof(Exec);	dlen -= sizeof(Exec);	segsize = text;	for(;;){		if(dlen == 0){			if((dlen = tftpread(ctlrno, &server, &tftpb, sizeof(tftpb.data))) < 0)				return -1;			p = tftpb.data;		}		if(segsize <= dlen)			i = segsize;		else			i = dlen;		memmove(addr, p, i); 		addr += i;		p += i;		segsize -= i;		dlen -= i; 		if(segsize <= 0){			if(data == 0)				break;			print("+%d", data);			segsize = data;			data = 0;			addr = (uchar*)PGROUND((ulong)addr);		}	}	nak(ctlrno, &server, 3, "ok", 0);		/* tftpclose */	print("+%d=%d\n", bss, total);	print("entry: 0x%lux\n", entry);

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