ref: 2e6f158f4dc9ebc6eb826041254221cba57c4019
dir: /sys/src/boot/pc/pxe.c/
#include <u.h>
#include "fns.h"
enum {
Tftp_READ = 1,
Tftp_WRITE = 2,
Tftp_DATA = 3,
Tftp_ACK = 4,
Tftp_ERROR = 5,
Tftp_OACK = 6,
TftpPort = 69,
Segsize = 512,
Maxpath = 64,
};
typedef uchar IP4[4];
typedef struct Tftp Tftp;
typedef struct Dhcp Dhcp;
struct Tftp
{
IP4 sip;
IP4 dip;
IP4 gip;
int sport;
int dport;
char *rp;
char *ep;
int seq;
int eof;
char pkt[2+2+Segsize];
char nul;
};
struct Dhcp
{
uchar opcode;
uchar hardware;
uchar hardlen;
uchar gatehops;
uchar ident[4];
uchar seconds[2];
uchar flags[2];
uchar cip[4];
uchar yip[4];
uchar sip[4];
uchar gip[4];
uchar mac[16];
char sname[64];
char bootfile[128];
};
int pxeinit(void);
int pxecall(int op, void *buf);
static void*
unfar(ulong seg, ulong off)
{
return (void*)((off & 0xFFFF) + (seg & 0xFFFF)*16);
}
static void
puts(void *x, ushort v)
{
uchar *p = x;
p[1] = (v>>8) & 0xFF;
p[0] = v & 0xFF;
}
static ushort
gets(void *x)
{
uchar *p = x;
return p[1]<<8 | p[0];
}
static void
hnputs(void *x, ushort v)
{
uchar *p = x;
p[0] = (v>>8) & 0xFF;
p[1] = v & 0xFF;
}
static ushort
nhgets(void *x)
{
uchar *p = x;
return p[0]<<8 | p[1];
}
static void
moveip(IP4 d, IP4 s)
{
memmove(d, s, sizeof(d));
}
void
unload(void)
{
struct {
uchar status[2];
uchar junk[10];
} buf;
static uchar shutdown[] = { 0x05, 0x070, 0x02, 0 };
uchar *o;
for(o = shutdown; *o; o++){
memset(&buf, 0, sizeof(buf));
if(pxecall(*o, &buf))
break;
}
}
static int
getip(IP4 yip, IP4 sip, IP4 gip, char mac[16])
{
struct {
uchar status[2];
uchar pkttype[2];
uchar bufsize[2];
uchar off[2];
uchar seg[2];
uchar lim[2];
} buf;
int i, r;
Dhcp *p;
memset(&buf, 0, sizeof(buf));
puts(buf.pkttype, 3);
if(r = pxecall(0x71, &buf))
return -r;
if((p = unfar(gets(buf.seg), gets(buf.off))) == 0)
return -1;
moveip(yip, p->yip);
moveip(sip, p->sip);
moveip(gip, p->gip);
mac[12] = 0;
for(i=0; i<6; i++){
mac[i*2] = hex[p->mac[i]>>4];
mac[i*2+1] = hex[p->mac[i]&15];
}
return 0;
}
static int
udpopen(IP4 sip)
{
struct {
uchar status[2];
uchar sip[4];
} buf;
puts(buf.status, 0);
moveip(buf.sip, sip);
return pxecall(0x30, &buf);
}
static int
udpclose(void)
{
uchar status[2];
puts(status, 0);
return pxecall(0x31, status);
}
static int
udpread(IP4 sip, IP4 dip, int *sport, int dport, int *len, void *data)
{
struct {
uchar status[2];
uchar sip[4];
uchar dip[4];
uchar sport[2];
uchar dport[2];
uchar len[2];
uchar off[2];
uchar seg[2];
} buf;
int r;
puts(buf.status, 0);
moveip(buf.sip, sip);
moveip(buf.dip, dip);
hnputs(buf.sport, *sport);
hnputs(buf.dport, dport);
puts(buf.len, *len);
puts(buf.off, (long)data);
puts(buf.seg, 0);
if(r = pxecall(0x32, &buf))
return r;
moveip(sip, buf.sip);
*sport = nhgets(buf.sport);
*len = gets(buf.len);
return 0;
}
static int
udpwrite(IP4 ip, IP4 gw, int sport, int dport, int len, void *data)
{
struct {
uchar status[2];
uchar ip[4];
uchar gw[4];
uchar sport[2];
uchar dport[2];
uchar len[2];
uchar off[2];
uchar seg[2];
} buf;
puts(buf.status, 0);
moveip(buf.ip, ip);
moveip(buf.gw, gw);
hnputs(buf.sport, sport);
hnputs(buf.dport, dport);
puts(buf.len, len);
puts(buf.off, (long)data);
puts(buf.seg, 0);
return pxecall(0x33, &buf);
}
int
read(void *f, void *data, int len)
{
Tftp *t = f;
int seq, n;
while(!t->eof && t->rp >= t->ep){
for(;;){
n = sizeof(t->pkt);
if(udpread(t->dip, t->sip, &t->dport, t->sport, &n, t->pkt))
continue;
if(n >= 4)
break;
}
switch(nhgets(t->pkt)){
case Tftp_DATA:
seq = nhgets(t->pkt+2);
if(seq > t->seq){
putc('?');
continue;
}
hnputs(t->pkt, Tftp_ACK);
while(udpwrite(t->dip, t->gip, t->sport, t->dport, 4, t->pkt))
putc('!');
if(seq < t->seq){
putc('@');
continue;
}
t->seq = seq+1;
n -= 4;
t->rp = t->pkt + 4;
t->ep = t->rp + n;
t->eof = n < Segsize;
break;
case Tftp_ERROR:
print(t->pkt+4);
print("\n");
default:
t->eof = 1;
return -1;
}
break;
}
n = t->ep - t->rp;
if(len > n)
len = n;
memmove(data, t->rp, len);
t->rp += len;
return len;
}
void
close(void *f)
{
Tftp *t = f;
t->eof = 1;
udpclose();
}
static int
tftpopen(Tftp *t, char *path, IP4 sip, IP4 dip, IP4 gip)
{
static ushort xport = 6666;
int r, n;
char *p;
moveip(t->sip, sip);
moveip(t->gip, gip);
memset(t->dip, 0, sizeof(t->dip));
t->sport = xport++;
t->dport = 0;
t->rp = t->ep = 0;
t->seq = 1;
t->eof = 0;
t->nul = 0;
if(r = udpopen(t->sip))
return r;
p = t->pkt;
hnputs(p, Tftp_READ); p += 2;
n = strlen(path)+1;
memmove(p, path, n); p += n;
memmove(p, "octet", 6); p += 6;
n = p - t->pkt;
for(;;){
if(r = udpwrite(dip, t->gip, t->sport, TftpPort, n, t->pkt))
break;
if(r = read(t, 0, 0))
break;
return 0;
}
close(t);
return r;
}
void
start(void *)
{
char mac[16], path[Maxpath], *kern;
IP4 yip, sip, gip;
void *f;
Tftp t;
if(pxeinit()){
print("pxe init\n");
halt();
}
if(getip(yip, sip, gip, mac)){
print("bad dhcp\n");
halt();
}
memmove(path, "/cfg/pxe/", 9);
memmove(path+9, mac, 13);
if(tftpopen(f = &t, path, yip, sip, gip))
if(tftpopen(f, "/cfg/pxe/default", yip, sip, gip)){
print("no config\n");
f = 0;
}
for(;;){
kern = configure(f, path); f = 0;
if(tftpopen(&t, kern, yip, sip, gip)){
print("not found\n");
continue;
}
print(bootkern(&t));
print("\n");
}
}