/*
* Receive data, and do something with it.
* Actually we receive a queue item which holds the data.
* If we free the item it will also free the data unless we have
* previously disassociated it using the NGI_GET_M() macro.
* Possibly send it out on another link after processing.
* Possibly do something different if it comes from different
* hooks. The caller will never free m, so if we use up this data or
* abort we must free it.
*
* If we want, we may decide to force this data to be queued and reprocessed
* at the netgraph NETISR time.
* We would do that by setting the HK_QUEUE flag on our hook. We would do that
* in the connect() method.
*/
static int
ng_xxx_rcvdata(hook_p hook, item_p item )
{
const xxx_p xxxp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
int chan = -2;
int dlci = -2;
int error;
struct mbuf *m;
NGI_GET_M(item, m);
if (NG_HOOK_PRIVATE(hook)) {
dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci;
chan = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->channel;
if (dlci != -1) {
/* If received on a DLCI hook process for this
* channel and pass it to the downstream module.
* Normally one would add a multiplexing header at
* the front here */
/* M_PREPEND(....) ; */
/* mtod(m, xxxxxx)->dlci = dlci; */
NG_FWD_NEW_DATA(error, item,
xxxp->downstream_hook.hook, m);
xxxp->packets_out++;
} else {
/* data came from the multiplexed link */
dlci = 1; /* get dlci from header */
/* madjust(....) *//* chop off header */
for (chan = 0; chan < XXX_NUM_DLCIS; chan++)
if (xxxp->channel[chan].dlci == dlci)
break;
if (chan == XXX_NUM_DLCIS) {
NG_FREE_ITEM(item);
NG_FREE_M(m);
return (ENETUNREACH);
}
/* If we were called at splnet, use the following:
* NG_SEND_DATA_ONLY(error, otherhook, m); if this
* node is running at some SPL other than SPLNET
* then you should use instead: error =
* ng_queueit(otherhook, m, NULL); m = NULL;
* This queues the data using the standard NETISR
* system and schedules the data to be picked
* up again once the system has moved to SPLNET and
* the processing of the data can continue. After
* these are run 'm' should be considered
* as invalid and NG_SEND_DATA actually zaps them. */
NG_FWD_NEW_DATA(error, item,
xxxp->channel[chan].hook, m);
xxxp->packets_in++;
}
} else {
/* It's the debug hook, throw it away.. */
if (hook == xxxp->downstream_hook.hook) {
NG_FREE_ITEM(item);
NG_FREE_M(m);
}
}
return 0;
}
/*
* Receive data
*/
static int
ngee_rcvdata(hook_p hook, item_p item)
{
int error;
struct mbuf *m;
struct ether_header *eh;
struct ether_addr tmpaddr;
/* Make sure we have an entire header */
NGI_GET_M(item, m);
if (m->m_len < sizeof(*eh) ) {
m = m_pullup(m, sizeof(*eh));
if (m == NULL) {
NG_FREE_ITEM(item);
return(EINVAL);
}
}
eh = mtod(m, struct ether_header *);
/* swap the source and destination fields */
bcopy(eh->ether_dhost, &tmpaddr, ETHER_ADDR_LEN);
bcopy(eh->ether_shost, eh->ether_dhost, ETHER_ADDR_LEN);
bcopy(&tmpaddr, eh->ether_shost, ETHER_ADDR_LEN);
NG_FWD_NEW_DATA(error, item, hook, m);
return (error);
}
/*
* Decode an incoming frame coming from the switch
*/
static int
ngfrm_decode(node_p node, item_p item)
{
const sc_p sc = NG_NODE_PRIVATE(node);
char *data;
int alen;
u_int dlci = 0;
int error = 0;
int ctxnum;
struct mbuf *m;
NGI_GET_M(item, m);
if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
error = ENOBUFS;
goto out;
}
data = mtod(m, char *);
if ((alen = sc->addrlen) == 0) {
sc->addrlen = alen = ngfrm_addrlen(data);
}
switch (alen) {
case 2:
SHIFTIN(makeup + 0, data[0], dlci);
SHIFTIN(makeup + 1, data[1], dlci);
break;
case 3:
SHIFTIN(makeup + 0, data[0], dlci);
SHIFTIN(makeup + 1, data[1], dlci);
SHIFTIN(makeup + 3, data[2], dlci); /* 3 and 2 is correct */
break;
case 4:
SHIFTIN(makeup + 0, data[0], dlci);
SHIFTIN(makeup + 1, data[1], dlci);
SHIFTIN(makeup + 2, data[2], dlci);
SHIFTIN(makeup + 3, data[3], dlci);
break;
default:
error = EINVAL;
goto out;
}
if (dlci > 1023) {
error = EINVAL;
goto out;
}
ctxnum = sc->ALT[dlci];
if ((ctxnum & CTX_VALID) && sc->channel[ctxnum &= CTX_VALUE].hook) {
/* Send it */
m_adj(m, alen);
NG_FWD_NEW_DATA(error, item, sc->channel[ctxnum].hook, m);
return (error);
} else {
error = ENETDOWN;
}
out:
NG_FREE_ITEM(item);
NG_FREE_M(m);
return (error);
}
/*
* Receive data packet
*/
static int
ngfrm_rcvdata(hook_p hook, item_p item)
{
struct ctxinfo *const ctxp = NG_HOOK_PRIVATE(hook);
int error = 0;
int dlci;
sc_p sc;
int alen;
char *data;
struct mbuf *m;
/* Data doesn't come in from just anywhere (e.g debug hook) */
if (ctxp == NULL) {
error = ENETDOWN;
goto bad;
}
/* If coming from downstream, decode it to a channel */
dlci = ctxp->dlci;
if (dlci == -1)
return (ngfrm_decode(NG_HOOK_NODE(hook), item));
NGI_GET_M(item, m);
/* Derive the softc we will need */
sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
/* If there is no live channel, throw it away */
if ((sc->downstream.hook == NULL)
|| ((ctxp->flags & CHAN_ACTIVE) == 0)) {
error = ENETDOWN;
goto bad;
}
/* Store the DLCI on the front of the packet */
alen = sc->addrlen;
if (alen == 0)
alen = 2; /* default value for transmit */
M_PREPEND(m, alen, M_DONTWAIT);
if (m == NULL) {
error = ENOBUFS;
goto bad;
}
data = mtod(m, char *);
/*
* Shift the lowest bits into the address field untill we are done.
* First byte is MSBits of addr so work backwards.
*/
switch (alen) {
case 2:
data[0] = data[1] = '\0';
SHIFTOUT(makeup + 1, data[1], dlci);
SHIFTOUT(makeup + 0, data[0], dlci);
data[1] |= BYTEX_EA;
break;
case 3:
data[0] = data[1] = data[2] = '\0';
SHIFTOUT(makeup + 3, data[2], dlci); /* 3 and 2 is correct */
SHIFTOUT(makeup + 1, data[1], dlci);
SHIFTOUT(makeup + 0, data[0], dlci);
data[2] |= BYTEX_EA;
break;
case 4:
data[0] = data[1] = data[2] = data[3] = '\0';
SHIFTOUT(makeup + 3, data[3], dlci);
SHIFTOUT(makeup + 2, data[2], dlci);
SHIFTOUT(makeup + 1, data[1], dlci);
SHIFTOUT(makeup + 0, data[0], dlci);
data[3] |= BYTEX_EA;
break;
default:
panic(__func__);
}
/* Send it */
NG_FWD_NEW_DATA(error, item, sc->downstream.hook, m);
return (error);
bad:
NG_FREE_ITEM(item);
NG_FREE_M(m);
return (error);
}
