ref: 0196ca7536c295b42e1d27ab8187a3d8e1bda328
dir: /sys/src/9/port/devether.c/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "pool.h"
#include "ureg.h"
#include "../port/error.h"
#include "../port/netif.h"
#include "../port/etherif.h"
#include "../ip/ip.h"
#include "../ip/ipv6.h"
extern int eipfmt(Fmt*);
extern ushort ipcsum(uchar *);
static Ether *etherxx[MaxEther];
static Ether *etherprobe(int cardno, int ctlrno, char *conf);
static void dmatproxy(Block*, int, uchar*, DMAT*);
Chan*
etherattach(char* spec)
{
ulong ctlrno;
char *conf;
Chan *chan;
ctlrno = 0;
if(*spec){
ctlrno = strtoul(spec, &conf, 10);
if(ctlrno >= MaxEther)
error(Enodev);
if(conf == spec)
error(Ebadspec);
if(*conf){
if(*conf != ':')
error(Ebadspec);
*conf++ = 0;
if(!iseve())
error(Enoattach);
if(etherxx[ctlrno] != nil)
error(Einuse);
etherxx[ctlrno] = etherprobe(-1, ctlrno, conf);
}
}
if(etherxx[ctlrno] == nil)
error(Enodev);
chan = devattach('l', spec);
if(waserror()){
chanfree(chan);
nexterror();
}
chan->dev = ctlrno;
if(etherxx[ctlrno]->attach)
etherxx[ctlrno]->attach(etherxx[ctlrno]);
poperror();
return chan;
}
static Walkqid*
etherwalk(Chan* chan, Chan* nchan, char** name, int nname)
{
return netifwalk(etherxx[chan->dev], chan, nchan, name, nname);
}
static int
etherstat(Chan* chan, uchar* dp, int n)
{
return netifstat(etherxx[chan->dev], chan, dp, n);
}
static Chan*
etheropen(Chan* chan, int omode)
{
return netifopen(etherxx[chan->dev], chan, omode);
}
static Chan*
ethercreate(Chan*, char*, int, ulong)
{
error(Eperm);
}
static void
etherclose(Chan* chan)
{
Ether *ether = etherxx[chan->dev];
if(NETTYPE(chan->qid.path) == Ndataqid && ether->f[NETID(chan->qid.path)]->bridge)
memset(ether->mactab, 0, sizeof(ether->mactab));
netifclose(ether, chan);
}
static long
etherread(Chan* chan, void* buf, long n, vlong off)
{
Ether *ether;
ulong offset = off;
ether = etherxx[chan->dev];
if((chan->qid.type & QTDIR) == 0 && ether->ifstat){
/*
* With some controllers it is necessary to reach
* into the chip to extract statistics.
*/
if(NETTYPE(chan->qid.path) == Nifstatqid)
return ether->ifstat(ether, buf, n, offset);
else if(NETTYPE(chan->qid.path) == Nstatqid)
ether->ifstat(ether, buf, 0, offset);
}
return netifread(ether, chan, buf, n, offset);
}
static Block*
etherbread(Chan* chan, long n, ulong offset)
{
return netifbread(etherxx[chan->dev], chan, n, offset);
}
static int
etherwstat(Chan* chan, uchar* dp, int n)
{
return netifwstat(etherxx[chan->dev], chan, dp, n);
}
static void
etherrtrace(Netfile* f, Etherpkt* pkt, int len)
{
Block *bp;
if(qfull(f->in))
return;
bp = iallocb(64);
if(bp == nil)
return;
memmove(bp->wp, pkt, len < 64 ? len : 64);
if(f->type != -2){
u32int ms = TK2MS(MACHP(0)->ticks);
bp->wp[58] = len>>8;
bp->wp[59] = len;
bp->wp[60] = ms>>24;
bp->wp[61] = ms>>16;
bp->wp[62] = ms>>8;
bp->wp[63] = ms;
}
bp->wp += 64;
qpass(f->in, bp);
}
static Macent*
macent(Ether *ether, uchar *ea)
{
u32int h = (ea[0] | ea[1]<<8 | ea[2]<<16 | ea[3]<<24) ^ (ea[4] | ea[5]<<8);
return ðer->mactab[h % nelem(ether->mactab)];
}
/*
* Multiplex the packet to all the connections which want it.
* If the packet is not to be used subsequently (tome || from == nil),
* attempt to simply pass it into one of the connections, thereby
* saving a copy of the data (usual case hopefully).
*/
static Block*
ethermux(Ether *ether, Block *bp, Netfile **from)
{
Block *xbp;
Etherpkt *pkt;
Netfile *f, *x, **fp;
int len, multi, tome, port, type, dispose;
len = BLEN(bp);
if(len < ETHERHDRSIZE)
goto Drop;
pkt = (Etherpkt*)bp->rp;
if(!(multi = pkt->d[0] & 1)){
tome = memcmp(pkt->d, ether->ea, Eaddrlen) == 0;
if(!tome && from != nil && ether->prom == 0)
return bp;
} else {
tome = 0;
if(from == nil && ether->prom == 0
&& memcmp(pkt->d, ether->bcast, Eaddrlen) != 0
&& !activemulti(ether, pkt->d, Eaddrlen))
goto Drop;
}
port = -1;
if(ether->prom){
if((from == nil || (*from)->bridge) && (pkt->s[0] & 1) == 0){
Macent *t = macent(ether, pkt->s);
t->port = from == nil ? 0 : 1+(from - ether->f);
memmove(t->ea, pkt->s, Eaddrlen);
}
if(!tome && !multi){
Macent *t = macent(ether, pkt->d);
if(memcmp(t->ea, pkt->d, Eaddrlen) == 0)
port = t->port;
}
}
x = nil;
type = (pkt->type[0]<<8)|pkt->type[1];
dispose = tome || from == nil || port > 0;
for(fp = ether->f; fp < ðer->f[Ntypes]; fp++){
if((f = *fp) == nil)
continue;
if(f->type != type && f->type >= 0)
continue;
if(!tome && !multi && !f->prom)
continue;
if(f->bypass)
continue;
if(f->bridge){
if(tome || fp == from)
continue;
if(port >= 0 && port != 1+(fp - ether->f))
continue;
}
if(f->headersonly || f->type == -2){
etherrtrace(f, pkt, len);
continue;
}
if(dispose && x == nil)
x = f;
else if((xbp = iallocb(len)) != nil){
memmove(xbp->wp, pkt, len);
xbp->wp += len;
xbp->flag = bp->flag;
if(qpass(f->in, xbp) < 0)
ether->soverflows++;
} else
ether->soverflows++;
}
if(x != nil){
if(qpass(x->in, bp) < 0)
ether->soverflows++;
return nil;
}
if(dispose){
Drop: freeb(bp);
return nil;
}
return bp;
}
void
etheriq(Ether* ether, Block* bp)
{
if(ether->bypass != nil){
freeb(bp);
return;
}
if(ether->dmat != nil)
dmatproxy(bp, 0, ether->ea, ether->dmat);
ether->inpackets++;
ethermux(ether, bp, nil);
}
static void
etheroq(Ether* ether, Block* bp, Netfile **from)
{
Netfile *x;
if((*from)->bridge == 0)
memmove(((Etherpkt*)bp->rp)->s, ether->ea, Eaddrlen);
if((*from)->bypass){
if(ether->dmat != nil)
dmatproxy(bp, 0, ether->ea, ether->dmat);
from = nil;
}
bp = ethermux(ether, bp, from);
if(bp == nil)
return;
if(ether->dmat != nil)
dmatproxy(bp, 1, ether->ea, ether->dmat);
if((x = ether->bypass) != nil){
if(qpass(x->in, bp) < 0)
ether->soverflows++;
return;
}
ether->outpackets++;
qbwrite(ether->oq, bp);
if(ether->transmit != nil)
ether->transmit(ether);
}
static long
etherwrite(Chan* chan, void* buf, long n, vlong)
{
Ether *ether = etherxx[chan->dev];
Block *bp;
int nn, onoff;
Cmdbuf *cb;
if(NETTYPE(chan->qid.path) != Ndataqid) {
nn = netifwrite(ether, chan, buf, n);
if(nn >= 0)
return nn;
cb = parsecmd(buf, n);
if(cb->f[0] && strcmp(cb->f[0], "nonblocking") == 0){
if(cb->nf <= 1)
onoff = 1;
else
onoff = atoi(cb->f[1]);
qnoblock(ether->oq, onoff);
free(cb);
return n;
}
free(cb);
if(ether->ctl!=nil)
return ether->ctl(ether,buf,n);
error(Ebadctl);
}
if(n > ether->maxmtu)
error(Etoobig);
if(n < ether->minmtu)
error(Etoosmall);
bp = allocb(n);
if(waserror()){
freeb(bp);
nexterror();
}
memmove(bp->rp, buf, n);
poperror();
bp->wp += n;
etheroq(ether, bp, ðer->f[NETID(chan->qid.path)]);
return n;
}
static long
etherbwrite(Chan* chan, Block* bp, ulong)
{
Ether *ether;
long n = BLEN(bp);
if(NETTYPE(chan->qid.path) != Ndataqid){
if(waserror()) {
freeb(bp);
nexterror();
}
n = etherwrite(chan, bp->rp, n, 0);
poperror();
freeb(bp);
return n;
}
ether = etherxx[chan->dev];
if(n > ether->maxmtu){
freeb(bp);
error(Etoobig);
}
if(n < ether->minmtu){
freeb(bp);
error(Etoosmall);
}
etheroq(ether, bp, ðer->f[NETID(chan->qid.path)]);
return n;
}
static struct {
char* type;
int (*reset)(Ether*);
} cards[MaxEther+1];
void
addethercard(char* t, int (*r)(Ether*))
{
static int ncard;
if(ncard == MaxEther)
panic("too many ether cards");
cards[ncard].type = t;
cards[ncard].reset = r;
ncard++;
}
static Ether*
etherprobe(int cardno, int ctlrno, char *conf)
{
int i, lg;
ulong mb, bsz;
Ether *ether;
ether = malloc(sizeof(Ether));
if(ether == nil){
print("etherprobe: no memory for Ether\n");
return nil;
}
memset(ether, 0, sizeof(Ether));
ether->tbdf = BUSUNKNOWN;
ether->irq = -1;
ether->ctlrno = ctlrno;
ether->mbps = 10;
ether->minmtu = ETHERMINTU;
ether->maxmtu = ETHERMAXTU;
if(cardno < 0){
if(conf != nil){
kstrdup(ðer->type, conf);
ether->nopt = tokenize(ether->type, ether->opt, nelem(ether->opt));
if(ether->nopt < 1)
goto Nope;
memmove(ðer->opt[0], ðer->opt[1], --ether->nopt*sizeof(ether->opt[0]));
} else if(isaconfig("ether", ctlrno, ether) == 0)
goto Nope;
for(cardno = 0; cards[cardno].type != nil; cardno++)
if(cistrcmp(cards[cardno].type, ether->type) == 0)
break;
if(cards[cardno].type == nil)
goto Nope;
for(i = 0; i < ether->nopt; i++){
if(strncmp(ether->opt[i], "ea=", 3) == 0){
if(parseether(ether->ea, ðer->opt[i][3]))
memset(ether->ea, 0, Eaddrlen);
}
}
}
if(cardno >= MaxEther || cards[cardno].type == nil)
goto Nope;
snprint(ether->name, sizeof(ether->name), "ether%d", ctlrno);
if(cards[cardno].reset(ether) < 0){
Nope:
if(conf != nil) free(ether->type); /* see kstrdup() above */
free(ether);
return nil;
}
ether->type = cards[cardno].type;
print("#l%d: %s: %dMbps port 0x%lluX irq %d ea %E\n",
ctlrno, ether->type, ether->mbps, (uvlong)ether->port, ether->irq, ether->ea);
/* compute log10(ether->mbps) into lg */
for(lg = 0, mb = ether->mbps; mb >= 10; lg++)
mb /= 10;
if (lg > 0)
lg--;
if (lg > 14) /* 2^(14+17) = 2³¹ */
lg = 14;
/* allocate larger output queues for higher-speed interfaces */
bsz = 1UL << (lg + 17); /* 2¹⁷ = 128K, bsz = 2ⁿ × 128K */
while (bsz > mainmem->maxsize / 8 && bsz > 128*1024)
bsz /= 2;
netifinit(ether, ether->name, Ntypes, bsz);
if(ether->oq == nil) {
ether->oq = qopen(bsz, Qmsg, 0, 0);
ether->limit = bsz;
}
if(ether->oq == nil)
panic("etherreset %s: can't allocate output queue of %ld bytes", ether->name, bsz);
ether->alen = Eaddrlen;
memmove(ether->addr, ether->ea, Eaddrlen);
memset(ether->bcast, 0xFF, Eaddrlen);
return ether;
}
static void netconsole(int);
static void
etherreset(void)
{
Ether *ether;
int cardno, ctlrno;
fmtinstall('E', eipfmt);
for(ctlrno = 0; ctlrno < MaxEther; ctlrno++){
if((ether = etherprobe(-1, ctlrno, nil)) == nil)
continue;
etherxx[ctlrno] = ether;
}
if(getconf("*noetherprobe") == nil){
cardno = ctlrno = 0;
while(cards[cardno].type != nil && ctlrno < MaxEther){
if(etherxx[ctlrno] != nil){
ctlrno++;
continue;
}
if((ether = etherprobe(cardno, ctlrno, nil)) == nil){
cardno++;
continue;
}
etherxx[ctlrno] = ether;
ctlrno++;
}
}
netconsole(1);
}
static void
ethershutdown(void)
{
Ether *ether;
int i;
netconsole(0);
for(i = 0; i < MaxEther; i++){
ether = etherxx[i];
if(ether == nil)
continue;
if(ether->shutdown == nil) {
print("#l%d: no shutdown function\n", i);
continue;
}
(*ether->shutdown)(ether);
}
}
#define POLY 0xedb88320
/* really slow 32 bit crc for ethers */
ulong
ethercrc(uchar *p, int len)
{
int i, j;
ulong crc, b;
crc = 0xffffffff;
for(i = 0; i < len; i++){
b = *p++;
for(j = 0; j < 8; j++){
crc = (crc>>1) ^ (((crc^b) & 1) ? POLY : 0);
b >>= 1;
}
}
return crc;
}
Dev etherdevtab = {
'l',
"ether",
etherreset,
devinit,
ethershutdown,
etherattach,
etherwalk,
etherstat,
etheropen,
ethercreate,
etherclose,
etherread,
etherbread,
etherwrite,
etherbwrite,
devremove,
etherwstat,
};
enum { PktHdr = 42 };
typedef struct Netconsole Netconsole;
struct Netconsole {
char buf[512];
int n;
Lock;
Ether *ether;
};
static Netconsole *netcons;
static void
netconsputc(Uart *, int c)
{
char *p;
u16int cs;
ilock(netcons);
netcons->buf[netcons->n++] = c;
if(c != '\n' && netcons->n < sizeof(netcons->buf)){
iunlock(netcons);
return;
}
p = netcons->buf;
p[16] = netcons->n - 14 >> 8;
p[17] = netcons->n - 14;
p[24] = 0;
p[25] = 0;
cs = ipcsum((uchar*) p + 14);
p[24] = cs >> 8;
p[25] = cs;
p[38] = netcons->n - 34 >> 8;
p[39] = netcons->n - 34;
memmove(p+Eaddrlen, netcons->ether->ea, Eaddrlen);
qiwrite(netcons->ether->oq, p, netcons->n);
netcons->n = PktHdr;
iunlock(netcons);
if(netcons->ether->transmit != nil)
netcons->ether->transmit(netcons->ether);
}
static PhysUart netconsphys = { .putc = netconsputc };
static Uart netconsuart = { .phys = &netconsphys };
static void
netconsole(int on)
{
char *p;
char *r;
int i;
int srcport, devno, dstport;
u8int srcip[4], dstip[4];
u64int dstmac;
Netconsole *nc;
if(!on){
if(consuart == &netconsuart)
consuart = nil;
return;
}
if((p = getconf("console")) == nil || strncmp(p, "net ", 4) != 0)
return;
p += 4;
for(i = 0; i < 4; i++){
srcip[i] = strtol(p, &r, 0);
p = r + 1;
if(i == 3) break;
if(*r != '.') goto err;
}
if(*r == '!'){
srcport = strtol(p, &r, 0);
p = r + 1;
}else
srcport = 6665;
if(*r == '/'){
devno = strtol(p, &r, 0);
p = r + 1;
}else
devno = 0;
if(*r != ',') goto err;
for(i = 0; i < 4; i++){
dstip[i] = strtol(p, &r, 0);
p = r + 1;
if(i == 3) break;
if(*r != '.') goto err;
}
if(*r == '!'){
dstport = strtol(p, &r, 0);
p = r + 1;
}else
dstport = 6666;
if(*r == '/'){
dstmac = strtoull(p, &r, 16);
if(r - p != 12) goto err;
}else
dstmac = ((uvlong)-1) >> 16;
if(*r != 0) goto err;
if(devno >= MaxEther || etherxx[devno] == nil){
print("netconsole: no device #l%d\n", devno);
return;
}
nc = malloc(sizeof(Netconsole));
if(nc == nil){
print("netconsole: out of memory");
return;
}
memset(nc, 0, sizeof(Netconsole));
nc->ether = etherxx[devno];
uchar header[PktHdr] = {
/* 0 */ dstmac >> 40, dstmac >> 32, dstmac >> 24, dstmac >> 16, dstmac >> 8, dstmac >> 0,
/* 6 */ 0, 0, 0, 0, 0, 0,
/* 12 */ 0x08, 0x00,
/* 14 */ 0x45, 0x00,
/* 16 */ 0x00, 0x00, /* total length */
/* 18 */ 0x00, 0x00, 0x00, 0x00,
/* 22 */ 64, /* ttl */
/* 23 */ 0x11, /* protocol */
/* 24 */ 0x00, 0x00, /* checksum */
/* 26 */ srcip[0], srcip[1], srcip[2], srcip[3],
/* 30 */ dstip[0], dstip[1], dstip[2], dstip[3],
/* 34 */ srcport >> 8, srcport, dstport >> 8, dstport,
/* 38 */ 0x00, 0x00, /* length */
/* 40 */ 0x00, 0x00 /* checksum */
};
memmove(nc->buf, header, PktHdr);
nc->n = PktHdr;
netcons = nc;
consuart = &netconsuart;
return;
err:
print("netconsole: invalid string %#q\n", getconf("console"));
print("netconsole: usage: srcip[!srcport][/srcdev],dstip[!dstport][/dstmac]\n");
}
/*
* Dynamic Mac Address Translation (DMAT)
*
* Wifi does not allow spoofing of the source mac which breaks
* bridging. To solve this we proxy mac addresses, maintaining
* a translation table from ip address to destination mac address.
* Upstream ARP and NDP packets get ther source mac address changed
* to proxy and a translation entry is added with the original mac
* for downstream translation. The proxy does not appear in the
* table.
*/
static void
dmatproxy(Block *bp, int upstream, uchar proxy[Eaddrlen], DMAT *t)
{
static uchar arp4[] = {
0x00, 0x01,
0x08, 0x00,
0x06, 0x04,
0x00,
};
uchar ip[IPaddrlen], mac[Eaddrlen], *targ, *end, *a, *o;
ulong csum, c, h;
Etherpkt *pkt;
int proto, i;
DMTE *te;
end = bp->wp;
pkt = (Etherpkt*)bp->rp;
a = pkt->data;
if(a >= end)
return;
if(upstream)
memmove(pkt->s, proxy, Eaddrlen);
else if(t->map == 0 || (pkt->d[0]&1) != 0 || memcmp(pkt->d, proxy, Eaddrlen) != 0)
return;
targ = nil;
switch(pkt->type[0]<<8 | pkt->type[1]){
default:
return;
case ETIP4:
case ETIP6:
switch(a[0]&0xF0){
default:
return;
case IP_VER4:
if(a+IP4HDR > end || (a[0]&15) < IP_HLEN4)
return;
v4tov6(ip, a+12+4*(upstream==0));
proto = a[9];
a += (a[0]&15)*4;
break;
case IP_VER6:
if(a+IP6HDR > end)
return;
memmove(ip, a+8+16*(upstream==0), 16);
proto = a[6];
a += IP6HDR;
break;
}
if(!upstream)
break;
switch(proto){
case ICMPv6:
if(a+8 > end)
return;
switch(a[0]){
default:
return;
case 133: /* Router Solicitation */
o = a+8;
break;
case 134: /* Router Advertisement */
o = a+8+8;
break;
case 136: /* Neighbor Advertisement */
targ = a+8;
/* wet floor */
case 135: /* Neighbor Solicitation */
o = a+8+16;
break;
case 137: /* Redirect */
o = a+8+16+16;
break;
}
memset(mac, 0xFF, Eaddrlen);
csum = (a[2]<<8 | a[3])^0xFFFF;
while(o+8 <= end && o[1] != 0){
switch(o[0]){
case SRC_LLADDR:
case TARGET_LLADDR:
for(i=0; i<Eaddrlen; i += 2)
csum += (o[2+i]<<8 | o[3+i])^0xFFFF;
memmove(mac, o+2, Eaddrlen);
memmove(o+2, proxy, Eaddrlen);
for(i=0; i<Eaddrlen; i += 2)
csum += (o[2+i]<<8 | o[3+i]);
break;
}
o += o[1]*8;
}
while((c = csum >> 16) != 0)
csum = (csum & 0xFFFF) + c;
csum ^= 0xFFFF;
a[2] = csum>>8;
a[3] = csum;
break;
case UDP: /* for BOOTP */
if(a+42 > end
|| (a[0]<<8 | a[1]) != 68
|| (a[2]<<8 | a[3]) != 67
|| a[8] != 1
|| a[9] != 1
|| a[10] != Eaddrlen
|| (a[18]&0x80) != 0
|| memcmp(a+36, proxy, Eaddrlen) == 0)
return;
csum = (a[6]<<8 | a[7])^0xFFFF;
/* set the broadcast flag so response reaches us */
csum += (a[18]<<8)^0xFFFF;
a[18] |= 0x80;
csum += (a[18]<<8);
while((c = csum >> 16) != 0)
csum = (csum & 0xFFFF) + c;
csum ^= 0xFFFF;
a[6] = csum>>8;
a[7] = csum;
default:
return;
}
break;
case ETARP:
if(a+26 > end || memcmp(a, arp4, sizeof(arp4)) != 0 || (a[7] != 1 && a[7] != 2))
return;
v4tov6(ip, a+14+10*(upstream==0));
if(upstream){
memmove(mac, a+8, Eaddrlen);
memmove(a+8, proxy, Eaddrlen);
}
break;
}
Again:
h = ( (ip[IPaddrlen-1] ^ proxy[2])<<24 |
(ip[IPaddrlen-2] ^ proxy[3])<<16 |
(ip[IPaddrlen-3] ^ proxy[4])<<8 |
(ip[IPaddrlen-4] ^ proxy[5]) ) % nelem(t->tab);
te = &t->tab[h];
h &= 63;
if(upstream){
if((mac[0]&1) != 0 || memcmp(mac, proxy, Eaddrlen) == 0)
return;
for(i=0; te->valid && i<nelem(t->tab); i++){
if(memcmp(te->ip, ip, IPaddrlen) == 0)
break;
if(++te >= &t->tab[nelem(t->tab)])
te = t->tab;
}
memmove(te->mac, mac, Eaddrlen);
memmove(te->ip, ip, IPaddrlen);
te->valid = 1;
t->map |= 1ULL<<h;
if(targ != nil){
memmove(ip, targ, IPaddrlen);
targ = nil;
goto Again;
}
} else {
if((t->map>>h & 1) == 0)
return;
for(i=0; te->valid && i<nelem(t->tab); i++){
if(memcmp(te->ip, ip, IPaddrlen) == 0){
memmove(pkt->d, te->mac, Eaddrlen);
return;
}
if(++te >= &t->tab[nelem(t->tab)])
te = t->tab;
}
}
}