freebsd-skq/lib/libstand/ether.c
tsoome 7303b6b47f loader: network read rework
The current read from network is working from up to down - we have some
protocol needing the data from the network, so we build the buffer space
for that protocol, add the extra space for headers and pass this buffer
down to be filled by nif get call in hope, we have guessed the incoming
packet size right. Amazingly enough this approach mostly does work, but
not always...

So, this update does work from down to up - we allocate buffer (based
on MTU or frame size info), fill it up, and pass on for upper layers.
The obvious problem is that when we should free the buffer - if at all.

In the current implementation the upper layer will free the packet on error
or when the packet is no longer needed.

While working on the issue, the additional issue did pop up - the bios
implementation does not have generic get/put interface but is using pxe
udpsend/udpreceive instead. So the udp calls are gone and undi interface
is implemented instead. Which in turn means slight other changes as we
do not need to have duplicated pxe implementation and can just use dev_net.

To align packet content, the actual read from nic is using shifted buffer by
ETHER_ALIGN (2).

Reviewed by:	bapt
Differential Revision:	https://reviews.freebsd.org/D10232
2017-05-06 20:32:27 +00:00

148 lines
4.0 KiB
C

/* $NetBSD: ether.c,v 1.11 1997/07/07 15:52:50 drochner Exp $ */
/*
* Copyright (c) 1992 Regents of the University of California.
* All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL)
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/socket.h>
#include <string.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include "stand.h"
#include "net.h"
#include "netif.h"
/* Caller must leave room for ethernet header in front!! */
ssize_t
sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype)
{
ssize_t n;
struct ether_header *eh;
#ifdef ETHER_DEBUG
if (debug)
printf("sendether: called\n");
#endif
eh = (struct ether_header *)pkt - 1;
len += sizeof(*eh);
MACPY(d->myea, eh->ether_shost); /* by byte */
MACPY(dea, eh->ether_dhost); /* by byte */
eh->ether_type = htons(etype);
n = netif_put(d, eh, len);
if (n == -1 || n < sizeof(*eh))
return (-1);
n -= sizeof(*eh);
return (n);
}
/*
* Get a packet of any Ethernet type, with our address or
* the broadcast address. Save the Ether type in etype.
* Unless there is an error, we pass the whole packet and the unencapsulated
* data.
*/
ssize_t
readether(struct iodesc *d, void **pkt, void **payload, time_t tleft,
uint16_t *etype)
{
ssize_t n;
struct ether_header *eh;
void *ptr;
#ifdef ETHER_DEBUG
if (debug)
printf("readether: called\n");
#endif
ptr = NULL;
n = netif_get(d, &ptr, tleft);
if (n == -1 || n < sizeof(*eh)) {
free(ptr);
return (-1);
}
eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN);
/* Validate Ethernet address. */
if (bcmp(d->myea, eh->ether_dhost, 6) != 0 &&
bcmp(bcea, eh->ether_dhost, 6) != 0) {
#ifdef ETHER_DEBUG
if (debug)
printf("readether: not ours (ea=%s)\n",
ether_sprintf(eh->ether_dhost));
#endif
free(ptr);
return (-1);
}
*pkt = ptr;
*payload = (void *)((uintptr_t)eh + sizeof(*eh));
*etype = ntohs(eh->ether_type);
n -= sizeof(*eh);
return (n);
}
/*
* Convert Ethernet address to printable (loggable) representation.
*/
static char digits[] = "0123456789abcdef";
char *
ether_sprintf(u_char *ap)
{
int i;
static char etherbuf[18];
char *cp = etherbuf;
for (i = 0; i < 6; i++) {
*cp++ = digits[*ap >> 4];
*cp++ = digits[*ap++ & 0xf];
*cp++ = ':';
}
*--cp = 0;
return (etherbuf);
}