/*-
 * Copyright (c) 2000-2001 Benno Rice
 * Copyright (c) 2007 Semihalf, Rafal Jaworowski <raj@semihalf.com>
 * All rights reserved.
 *
 * 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 AUTHOR 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 AUTHOR 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.
 */

#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>

#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>

#include <stand.h>
#include <net.h>
#include <netif.h>

#include "api_public.h"
#include "glue.h"
#include "libuboot.h"
#include "dev_net.h"

static int      net_probe(struct netif *, void *);
static int      net_match(struct netif *, void *);
static void     net_init(struct iodesc *, void *);
static ssize_t  net_get(struct iodesc *, void **, time_t);
static ssize_t  net_put(struct iodesc *, void *, size_t);
static void     net_end(struct netif *);

extern struct netif_stats net_stats[];

struct netif_dif net_ifs[] = {
        /*      dif_unit        dif_nsel        dif_stats       dif_private */
        {       0,              1,              &net_stats[0],  0,      },
};

struct netif_stats net_stats[nitems(net_ifs)];

struct netif_driver uboot_net = {
        "uboot_eth",            /* netif_bname */
        net_match,              /* netif_match */
        net_probe,              /* netif_probe */
        net_init,               /* netif_init */
        net_get,                /* netif_get */
        net_put,                /* netif_put */
        net_end,                /* netif_end */
        net_ifs,                /* netif_ifs */
        nitems(net_ifs)         /* netif_nifs */
};

struct uboot_softc {
        uint32_t        sc_pad;
        uint8_t         sc_rxbuf[ETHER_MAX_LEN];
        uint8_t         sc_txbuf[ETHER_MAX_LEN + PKTALIGN];
        uint8_t         *sc_txbufp;
        int             sc_handle;      /* device handle for ub_dev_xxx */
};

static struct uboot_softc uboot_softc;

/*
 * get_env_net_params()
 *
 * Attempt to obtain all the parms we need for netbooting from the U-Boot
 * environment.  If we fail to obtain the values it may still be possible to
 * netboot; the net_dev code will attempt to get the values from bootp, rarp,
 * and other such sources.
 *
 * If rootip.s_addr is non-zero net_dev assumes the required global variables
 * are set and skips the bootp inquiry.  For that reason, we don't set rootip
 * until we've verified that we have at least the minimum required info.
 *
 * This is called from netif_init() which can result in it getting called
 * multiple times, by design.  The network code at higher layers zeroes out
 * rootip when it closes a network interface, so if it gets opened again we have
 * to obtain all this info again.
 */
static void
get_env_net_params(void)
{
        char *envstr;
        in_addr_t rootaddr, serveraddr;

        /*
         * Silently get out right away if we don't have rootpath, because none
         * of the other info we obtain below is sufficient to boot without it.
         *
         * If we do have rootpath, copy it into the global var and also set
         * dhcp.root-path in the env.  If we don't get all the other info from
         * the u-boot env below, we will still try dhcp/bootp, but the server-
         * provided path will not replace the user-provided value we set here.
         */
        if ((envstr = ub_env_get("rootpath")) == NULL)
                return;
        strlcpy(rootpath, envstr, sizeof(rootpath));
        setenv("dhcp.root-path", rootpath, 0);

        /*
         * Our own IP address must be valid.  Silently get out if it's not set,
         * but whine if it's there and we can't parse it.
         */
        if ((envstr = ub_env_get("ipaddr")) == NULL)
                return;
        if ((myip.s_addr = inet_addr(envstr)) == INADDR_NONE) {
                printf("Could not parse ipaddr '%s'\n", envstr);
                return;
        }

        /*
         * Netmask is optional, default to the "natural" netmask for our IP, but
         * whine if it was provided and we couldn't parse it.
         */
        if ((envstr = ub_env_get("netmask")) != NULL &&
            (netmask = inet_addr(envstr)) == INADDR_NONE) {
                printf("Could not parse netmask '%s'\n", envstr);
        }
        if (netmask == INADDR_NONE) {
                if (IN_CLASSA(myip.s_addr))
                        netmask = IN_CLASSA_NET;
                else if (IN_CLASSB(myip.s_addr))
                        netmask = IN_CLASSB_NET;
                else
                        netmask = IN_CLASSC_NET;
        }

        /*
         * Get optional serverip before rootpath; the latter can override it.
         * Whine only if it's present but can't be parsed.
         */
        serveraddr = INADDR_NONE;
        if ((envstr = ub_env_get("serverip")) != NULL) {
                if ((serveraddr = inet_addr(envstr)) == INADDR_NONE) 
                        printf("Could not parse serverip '%s'\n", envstr);
        }

        /*
         * There must be a rootpath.  It may be ip:/path or it may be just the
         * path in which case the ip needs to be in serverip.
         */
        rootaddr = net_parse_rootpath();
        if (rootaddr == INADDR_NONE)
                rootaddr = serveraddr;
        if (rootaddr == INADDR_NONE) {
                printf("No server address for rootpath '%s'\n", envstr);
                return;
        }
        rootip.s_addr = rootaddr;

        /*
         * Gateway IP is optional unless rootip is on a different net in which
         * case whine if it's missing or we can't parse it, and set rootip addr
         * to zero, which signals to other network code that network params
         * aren't set (so it will try dhcp, bootp, etc).
         */
        envstr = ub_env_get("gatewayip");
        if (!SAMENET(myip, rootip, netmask)) {
                if (envstr == NULL)  {
                        printf("Need gatewayip for a root server on a "
                            "different network.\n");
                        rootip.s_addr = 0;
                        return;
                }
                if ((gateip.s_addr = inet_addr(envstr)) == INADDR_NONE) {
                        printf("Could not parse gatewayip '%s'\n", envstr);
                        rootip.s_addr = 0;
                        return;
                }
        }
}

static int
net_match(struct netif *nif, void *machdep_hint)
{
        char **a = (char **)machdep_hint;

        if (memcmp("net", *a, 3) == 0)
                return (1);

        printf("net_match: could not match network device\n");
        return (0);
}

static int
net_probe(struct netif *nif, void *machdep_hint)
{
        struct device_info *di;
        int i;

        for (i = 0; i < devs_no; i++)
                if ((di = ub_dev_get(i)) != NULL)
                        if (di->type == DEV_TYP_NET)
                                break;

        if (i == devs_no) {
                printf("net_probe: no network devices found, maybe not"
                    " enumerated yet..?\n");
                return (-1);
        }

#if defined(NETIF_DEBUG)
        printf("net_probe: network device found: %d\n", i);
#endif
        uboot_softc.sc_handle = i;

        return (0);
}

static ssize_t
net_put(struct iodesc *desc, void *pkt, size_t len)
{
        struct netif *nif = desc->io_netif;
        struct uboot_softc *sc = nif->nif_devdata;
        size_t sendlen;
        ssize_t rv;

#if defined(NETIF_DEBUG)
        struct ether_header *eh;

        printf("net_put: desc %p, pkt %p, len %d\n", desc, pkt, len);
        eh = pkt;
        printf("dst: %s ", ether_sprintf(eh->ether_dhost));
        printf("src: %s ", ether_sprintf(eh->ether_shost));
        printf("type: 0x%x\n", eh->ether_type & 0xffff);
#endif

        if (len < ETHER_MIN_LEN - ETHER_CRC_LEN) {
                sendlen = ETHER_MIN_LEN - ETHER_CRC_LEN;
                bzero(sc->sc_txbufp, sendlen);
        } else
                sendlen = len;

        memcpy(sc->sc_txbufp, pkt, len);

        rv = ub_dev_send(sc->sc_handle, sc->sc_txbufp, sendlen);

#if defined(NETIF_DEBUG)
        printf("net_put: ub_send returned %d\n", rv);
#endif
        if (rv == 0)
                rv = len;
        else
                rv = -1;

        return (rv);
}

static ssize_t
net_get(struct iodesc *desc, void **pkt, time_t timeout)
{
        struct netif *nif = desc->io_netif;
        struct uboot_softc *sc = nif->nif_devdata;
        time_t t;
        int err, rlen;
        size_t len;
        char *buf;

#if defined(NETIF_DEBUG)
        printf("net_get: pkt %p, timeout %d\n", pkt, timeout);
#endif
        t = getsecs();
        len = sizeof(sc->sc_rxbuf);
        do {
                err = ub_dev_recv(sc->sc_handle, sc->sc_rxbuf, len, &rlen);

                if (err != 0) {
                        printf("net_get: ub_dev_recv() failed, error=%d\n",
                            err);
                        rlen = 0;
                        break;
                }
        } while ((rlen == -1 || rlen == 0) && (getsecs() - t < timeout));

#if defined(NETIF_DEBUG)
        printf("net_get: received len %d (%x)\n", rlen, rlen);
#endif

        if (rlen > 0) {
                buf = malloc(rlen + ETHER_ALIGN);
                if (buf == NULL)
                        return (-1);
                memcpy(buf + ETHER_ALIGN, sc->sc_rxbuf, rlen);
                *pkt = buf;
                return ((ssize_t)rlen);
        }

        return (-1);
}

static void
net_init(struct iodesc *desc, void *machdep_hint)
{
        struct netif *nif = desc->io_netif;
        struct uboot_softc *sc;
        struct device_info *di;
        int err;

        sc = nif->nif_devdata = &uboot_softc;

        if ((err = ub_dev_open(sc->sc_handle)) != 0)
                panic("%s%d: initialisation failed with error %d",
                    nif->nif_driver->netif_bname, nif->nif_unit, err);

        /* Get MAC address */
        di = ub_dev_get(sc->sc_handle);
        memcpy(desc->myea, di->di_net.hwaddr, 6);
        if (memcmp (desc->myea, "\0\0\0\0\0\0", 6) == 0) {
                panic("%s%d: empty ethernet address!",
                    nif->nif_driver->netif_bname, nif->nif_unit);
        }

        /* Attempt to get netboot params from the u-boot env. */
        get_env_net_params();
        if (myip.s_addr != 0)
                desc->myip = myip;

#if defined(NETIF_DEBUG)
        printf("network: %s%d attached to %s\n", nif->nif_driver->netif_bname,
            nif->nif_unit, ether_sprintf(desc->myea));
#endif

        /* Set correct alignment for TX packets */
        sc->sc_txbufp = sc->sc_txbuf;
        if ((unsigned long)sc->sc_txbufp % PKTALIGN)
                sc->sc_txbufp += PKTALIGN -
                    (unsigned long)sc->sc_txbufp % PKTALIGN;
}

static void
net_end(struct netif *nif)
{
        struct uboot_softc *sc = nif->nif_devdata;
        int err;

        if ((err = ub_dev_close(sc->sc_handle)) != 0)
                panic("%s%d: net_end failed with error %d",
                    nif->nif_driver->netif_bname, nif->nif_unit, err);
}