/*      $NetBSD: dev_net.c,v 1.27 2019/03/31 20:08:45 christos Exp $    */

/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Gordon W. Ross.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/

/*
* This module implements a "raw device" interface suitable for
* use by the stand-alone I/O library NFS code.  This interface
* does not support any "block" access, and exists only for the
* purpose of initializing the network interface, getting boot
* parameters, and performing the NFS mount.
*
* At open time, this does:
*
* find interface      - netif_open()
* RARP for IP address - rarp_getipaddress()
* RPC/bootparams      - callrpc(d, RPC_BOOTPARAMS, ...)
* RPC/mountd          - nfs_mount(sock, ip, path)
*
* the root file handle from mountd is saved in a global
* for use by the NFS open code (NFS/lookup).
*/

#include <sys/param.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>

#include <lib/libkern/libkern.h>

#include "stand.h"
#include "net.h"
#include "netif.h"
#include "nfs.h"
#include "bootparam.h"
#include "dev_net.h"
#ifdef SUPPORT_BOOTP
#include "bootp.h"
#endif

extern int nfs_root_node[];     /* XXX - get from nfs_mount() */

static int netdev_sock = -1;
static int netdev_opens;

static int net_getparams(int);

/*
* Called by devopen after it sets f->f_dev to our devsw entry.
* This opens the low-level device and sets f->f_devdata.
* This is declared with variable arguments...
*/
int
net_open(struct open_file *f, ...)
{
       va_list ap;
       char *devname;          /* Device part of file name (or NULL). */
       int error = 0;

       va_start(ap, f);
       devname = va_arg(ap, char *);
       va_end(ap);

#ifdef  NETIF_DEBUG
       if (debug)
               printf("%s\n", devname);
#endif

       /* On first open, do netif open, mount, etc. */
       if (netdev_opens == 0) {
               /* Find network interface. */
               if (netdev_sock < 0) {
                       netdev_sock = netif_open(devname);
                       if (netdev_sock < 0) {
                               printf("netif_open() failed\n");
                               return ENXIO;
                       }
#ifdef NETIF_DEBUG
                       if (debug)
                               printf("netif_open() succeeded\n");
#endif
               }
               if (rootip.s_addr == 0) {
                       /* Get root IP address, and path, etc. */
                       error = net_getparams(netdev_sock);
                       if (error) {
                               /* getparams makes its own noise */
                               goto fail;
                       }
                       /* Get the NFS file handle (mountd). */
                       error = nfs_mount(netdev_sock, rootip, rootpath);
                       if (error) {
                               printf("NFS mount error=%d\n", errno);
                               rootip.s_addr = 0;
                       fail:
                               netif_close(netdev_sock);
                               netdev_sock = -1;
                               return error;
                       }
#ifdef NETIF_DEBUG
                       if (debug)
                               printf("NFS mount succeeded\n");
#endif
               }
       }
       netdev_opens++;
       f->f_devdata = nfs_root_node;
       return error;
}

int
net_close(struct open_file *f)
{

#ifdef  NETIF_DEBUG
       if (debug)
               printf("net_close: opens=%d\n", netdev_opens);
#endif

       /* On last close, do netif close, etc. */
       f->f_devdata = NULL;
       /* Extra close call? */
       if (netdev_opens <= 0)
               return 0;
       netdev_opens--;
       /* Not last close? */
       if (netdev_opens > 0)
               return 0;
       rootip.s_addr = 0;
       if (netdev_sock >= 0) {
#ifdef NETIF_DEBUG
               if (debug)
                       printf("%s: calling netif_close()\n", __func__);
#endif
               netif_close(netdev_sock);
               netdev_sock = -1;
       }
       return 0;
}

int
net_ioctl(struct open_file *f, u_long cmd, void *data)
{

       return EIO;
}

int
net_strategy(void *devdata, int rw, daddr_t blk, size_t size, void *buf,
       size_t *rsize)
{

       return EIO;
}


/*
* Get info for NFS boot: our IP address, our hostname,
* server IP address, and our root path on the server.
* There are two ways to do this:  The old, Sun way,
* and the more modern, BOOTP way. (RFC951, RFC1048)
*
* The default is to use the Sun bootparams RPC
* (because that is what the kernel will do).
* MD code can make try_bootp initialied data,
* which will override this common definition.
*/
#ifdef  SUPPORT_BOOTP
int try_bootp;
#endif

static int
net_getparams(int sock)
{
       char buf[MAXHOSTNAMELEN];
       n_long smask;

#ifdef  SUPPORT_BOOTP
       /*
        * Try to get boot info using BOOTP.  If we succeed, then
        * the server IP address, gateway, and root path will all
        * be initialized.  If any remain uninitialized, we will
        * use RARP and RPC/bootparam (the Sun way) to get them.
        */
       if (try_bootp)
               bootp(sock);
       if (myip.s_addr != 0)
               return 0;
#ifdef NETIF_DEBUG
       if (debug)
               printf("BOOTP failed, trying RARP/RPC...\n");
#endif
#endif

       /*
        * Use RARP to get our IP address.  This also sets our
        * netmask to the "natural" default for our address.
        */
       if (rarp_getipaddress(sock)) {
               printf("RARP failed\n");
               return EIO;
       }
#ifdef NETIF_DEBUG
       if (debug)
               printf("client addr: %s\n", inet_ntoa(myip));
#endif

       /* Get our hostname, server IP address, gateway. */
       if (bp_whoami(sock)) {
               printf("bootparam/whoami RPC failed\n");
               return EIO;
       }
#ifdef NETIF_DEBUG
       if (debug)
               printf("client name: %s\n", hostname);
#endif

       /*
        * Ignore the gateway from whoami (unreliable).
        * Use the "gateway" parameter instead.
        */
       smask = 0;
       gateip.s_addr = 0;
       if (bp_getfile(sock, "gateway", &gateip, buf)) {
               printf("%s: gateway bootparam missing\n", __func__);
       } else {
               /* Got it!  Parse the netmask. */
               smask = inet_addr(buf);
       }
       if (smask) {
               netmask = smask;
#ifdef NETIF_DEBUG
               if (debug)
                       printf("subnet mask: %s\n", intoa(netmask));
#endif
       }
#ifdef NETIF_DEBUG
       if (debug)
               if (gateip.s_addr)
                       printf("net gateway: %s\n", inet_ntoa(gateip));
#endif

       /* Get the root server and pathname. */
       if (bp_getfile(sock, "root", &rootip, rootpath)) {
               printf("bootparam/getfile RPC failed\n");
               return EIO;
       }

#ifdef NETIF_DEBUG
       if (debug) {
               printf("server addr: %s\n", inet_ntoa(rootip));
               printf("server path: %s\n", rootpath);
       }
#endif

       return 0;
}