/*      $NetBSD: qop_red.c,v 1.5 2002/03/05 04:11:53 itojun Exp $       */
/*      $KAME: qop_red.c,v 1.6 2001/12/03 08:20:55 kjc Exp $    */
/*
 * Copyright (C) 1999-2000
 *      Sony Computer Science Laboratories, Inc.  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 SONY CSL 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 SONY CSL 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/socket.h>
#include <sys/sockio.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <syslog.h>
#include <netdb.h>

#include <altq/altq.h>
#include <altq/altq_red.h>
#include "altq_qop.h"
#include "qop_red.h"

static int red_attach(struct ifinfo *);
static int red_detach(struct ifinfo *);
static int red_enable(struct ifinfo *);
static int red_disable(struct ifinfo *);

#define RED_DEVICE      "/dev/altq/red"

static int red_fd = -1;
static int red_refcount = 0;

static struct qdisc_ops red_qdisc = {
        ALTQT_RED,
        "red",
        red_attach,
        red_detach,
        NULL,                   /* clear */
        red_enable,
        red_disable,
        NULL,                   /* add class */
        NULL,                   /* modify class */
        NULL,                   /* delete class */
        NULL,                   /* add filter */
        NULL                    /* delete filter */
};

/*
 * parser interface
 */
#define EQUAL(s1, s2)   (strcmp((s1), (s2)) == 0)

int
red_interface_parser(const char *ifname, int argc, char **argv)
{
        u_int   bandwidth = 100000000;  /* 100Mbps */
        u_int   tbrsize = 0;
        int     weight = 0;             /* 0: use default */
        int     inv_pmax = 0;           /* 0: use default */
        int     th_min = 0;             /* 0: use default */
        int     th_max = 0;             /* 0: use default */
        int     qlimit = 60;
        int     pkttime = 0;
        int     flags = 0;
        int     packet_size = 1000;

        /*
         * process options
         */
        while (argc > 0) {
                if (EQUAL(*argv, "bandwidth")) {
                        argc--; argv++;
                        if (argc > 0)
                                bandwidth = atobps(*argv);
                } else if (EQUAL(*argv, "tbrsize")) {
                        argc--; argv++;
                        if (argc > 0)
                                tbrsize = atobytes(*argv);
                } else if (EQUAL(*argv, "packetsize")) {
                        argc--; argv++;
                        if (argc > 0)
                                packet_size = atobytes(*argv);
                } else if (EQUAL(*argv, "weight")) {
                        argc--; argv++;
                        if (argc > 0)
                                weight = (int)strtol(*argv, NULL, 0);
                } else if (EQUAL(*argv, "qlimit")) {
                        argc--; argv++;
                        if (argc > 0)
                                qlimit = (int)strtol(*argv, NULL, 0);
                } else if (EQUAL(*argv, "thmin")) {
                        argc--; argv++;
                        if (argc > 0)
                                th_min = (int)strtol(*argv, NULL, 0);
                } else if (EQUAL(*argv, "thmax")) {
                        argc--; argv++;
                        if (argc > 0)
                                th_max = (int)strtol(*argv, NULL, 0);
                } else if (EQUAL(*argv, "invpmax")) {
                        argc--; argv++;
                        if (argc > 0)
                                inv_pmax = (int)strtol(*argv, NULL, 0);
                } else if (EQUAL(*argv, "red")) {
                        /* just skip */
                } else if (EQUAL(*argv, "ecn")) {
                        flags |= REDF_ECN;
                } else if (EQUAL(*argv, "flowvalve")) {
                        flags |= REDF_FLOWVALVE;
                } else {
                        LOG(LOG_ERR, 0, "Unknown keyword '%s'", *argv);
                        return (0);
                }
                argc--; argv++;
        }

        if (qcmd_tbr_register(ifname, bandwidth, tbrsize) != 0)
                return (0);

        pkttime = packet_size * 8 * 1000 / (bandwidth / 1000);
        if (weight != 0) {
                /* check if weight is power of 2 */
                int i, w;
                
                w = weight;
                for (i = 0; w > 1; i++)
                        w = w >> 1;
                w = 1 << i;
                if (weight != w) {
                        LOG(LOG_ERR, 0, "weight %d: should be power of 2",
                            weight);
                        return (0);
                }
        }

        if (qcmd_red_add_if(ifname, bandwidth, weight, inv_pmax,
                            th_min, th_max, qlimit, pkttime, flags) != 0)
                return (0);
        return (1);
}

/*
 * qcmd api
 */
int
qcmd_red_add_if(const char *ifname, u_int bandwidth, int weight,
                int inv_pmax, int th_min, int th_max, int qlimit,
                int pkttime, int flags)
{
        int error;
        
        error = qop_red_add_if(NULL, ifname, bandwidth, weight, inv_pmax,
                               th_min, th_max, qlimit, pkttime, flags);
        if (error != 0)
                LOG(LOG_ERR, errno, "%s: can't add red on interface '%s'",
                    qoperror(error), ifname);
        return (error);
}

/*
 * qop api
 */
int 
qop_red_add_if(struct ifinfo **rp, const char *ifname,
               u_int bandwidth, int weight, int inv_pmax, int th_min,
               int th_max, int qlimit, int pkttime, int flags)
{
        struct ifinfo *ifinfo = NULL;
        struct red_ifinfo *red_ifinfo;
        int error;

        if ((red_ifinfo = calloc(1, sizeof(*red_ifinfo))) == NULL)
                return (QOPERR_NOMEM);
        red_ifinfo->weight   = weight;
        red_ifinfo->inv_pmax = inv_pmax;
        red_ifinfo->th_min   = th_min;
        red_ifinfo->th_max   = th_max;
        red_ifinfo->qlimit   = qlimit;
        red_ifinfo->pkttime  = pkttime;
        red_ifinfo->flags    = flags;

        error = qop_add_if(&ifinfo, ifname, bandwidth,
                           &red_qdisc, red_ifinfo);
        if (error != 0) {
                free(red_ifinfo);
                return (error);
        }

        if (rp != NULL)
                *rp = ifinfo;
        return (0);
}

/*
 *  system call interfaces for qdisc_ops
 */
static int
red_attach(struct ifinfo *ifinfo)
{
        struct red_interface iface;
        struct red_ifinfo *red_ifinfo;
        struct red_conf conf;

        if (red_fd < 0 &&
            (red_fd = open(RED_DEVICE, O_RDWR)) < 0 &&
            (red_fd = open_module(RED_DEVICE, O_RDWR)) < 0) {
                LOG(LOG_ERR, errno, "RED open");
                return (QOPERR_SYSCALL);
        }

        red_refcount++;
        memset(&iface, 0, sizeof(iface));
        strncpy(iface.red_ifname, ifinfo->ifname, IFNAMSIZ);

        if (ioctl(red_fd, RED_IF_ATTACH, &iface) < 0)
                return (QOPERR_SYSCALL);

        /* set red parameters */
        red_ifinfo = (struct red_ifinfo *)ifinfo->private;
        memset(&conf, 0, sizeof(conf));
        strncpy(conf.iface.red_ifname, ifinfo->ifname, IFNAMSIZ);
        conf.red_weight   = red_ifinfo->weight;
        conf.red_inv_pmax = red_ifinfo->inv_pmax;
        conf.red_thmin    = red_ifinfo->th_min;
        conf.red_thmax    = red_ifinfo->th_max;
        conf.red_limit    = red_ifinfo->qlimit;
        conf.red_flags    = red_ifinfo->flags;
        if (ioctl(red_fd, RED_CONFIG, &conf) < 0)
                return (QOPERR_SYSCALL);

#if 1
        LOG(LOG_INFO, 0, "red attached to %s", iface.red_ifname);
#endif
        return (0);
}

static int
red_detach(struct ifinfo *ifinfo)
{
        struct red_interface iface;
        
        memset(&iface, 0, sizeof(iface));
        strncpy(iface.red_ifname, ifinfo->ifname, IFNAMSIZ);

        if (ioctl(red_fd, RED_IF_DETACH, &iface) < 0)
                return (QOPERR_SYSCALL);

        if (--red_refcount == 0) {
                close(red_fd);
                red_fd = -1;
        }
        return (0);
}

static int
red_enable(struct ifinfo *ifinfo)
{
        struct red_interface iface;

        memset(&iface, 0, sizeof(iface));
        strncpy(iface.red_ifname, ifinfo->ifname, IFNAMSIZ);

        if (ioctl(red_fd, RED_ENABLE, &iface) < 0)
                return (QOPERR_SYSCALL);
        return (0);
}

static int
red_disable(struct ifinfo *ifinfo)
{
        struct red_interface iface;

        memset(&iface, 0, sizeof(iface));
        strncpy(iface.red_ifname, ifinfo->ifname, IFNAMSIZ);

        if (ioctl(red_fd, RED_DISABLE, &iface) < 0)
                return (QOPERR_SYSCALL);
        return (0);
}