/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (C) 2018 Vincenzo Maffione
 * 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.
 */


#if defined(__FreeBSD__)
#include <sys/cdefs.h> /* prerequisite */
#include <sys/types.h>
#include <sys/param.h>  /* defines used in kernel.h */
#include <sys/filio.h>  /* FIONBIO */
#include <sys/malloc.h>
#include <sys/socketvar.h>      /* struct socket */
#include <sys/socket.h> /* sockaddrs */
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/bpf.h>            /* BIOCIMMEDIATE */
#include <machine/bus.h>        /* bus_dmamap_* */
#include <sys/endian.h>
#elif defined(linux)
#include "bsd_glue.h"
#elif defined(__APPLE__)
#warning OSX support is only partial
#include "osx_glue.h"
#elif defined (_WIN32)
#include "win_glue.h"
#endif

/*
 * common headers
 */
#include <net/netmap.h>
#include <dev/netmap/netmap_kern.h>
#include <dev/netmap/netmap_bdg.h>

static int
nmreq_register_from_legacy(struct nmreq *nmr, struct nmreq_header *hdr,
                                struct nmreq_register *req)
{
        req->nr_offset = nmr->nr_offset;
        req->nr_memsize = nmr->nr_memsize;
        req->nr_tx_slots = nmr->nr_tx_slots;
        req->nr_rx_slots = nmr->nr_rx_slots;
        req->nr_tx_rings = nmr->nr_tx_rings;
        req->nr_rx_rings = nmr->nr_rx_rings;
        req->nr_host_tx_rings = 0;
        req->nr_host_rx_rings = 0;
        req->nr_mem_id = nmr->nr_arg2;
        req->nr_ringid = nmr->nr_ringid & NETMAP_RING_MASK;
        if ((nmr->nr_flags & NR_REG_MASK) == NR_REG_DEFAULT) {
                /* Convert the older nmr->nr_ringid (original
                 * netmap control API) to nmr->nr_flags. */
                u_int regmode = NR_REG_DEFAULT;
                if (nmr->nr_ringid & NETMAP_SW_RING) {
                        regmode = NR_REG_SW;
                } else if (nmr->nr_ringid & NETMAP_HW_RING) {
                        regmode = NR_REG_ONE_NIC;
                } else {
                        regmode = NR_REG_ALL_NIC;
                }
                req->nr_mode = regmode;
        } else {
                req->nr_mode = nmr->nr_flags & NR_REG_MASK;
        }

        /* Fix nr_name, nr_mode and nr_ringid to handle pipe requests. */
        if (req->nr_mode == NR_REG_PIPE_MASTER ||
                        req->nr_mode == NR_REG_PIPE_SLAVE) {
                char suffix[10];
                snprintf(suffix, sizeof(suffix), "%c%d",
                        (req->nr_mode == NR_REG_PIPE_MASTER ? '{' : '}'),
                        req->nr_ringid);
                if (strlen(hdr->nr_name) + strlen(suffix)
                                        >= sizeof(hdr->nr_name)) {
                        /* No space for the pipe suffix. */
                        return ENOBUFS;
                }
                strlcat(hdr->nr_name, suffix, sizeof(hdr->nr_name));
                req->nr_mode = NR_REG_ALL_NIC;
                req->nr_ringid = 0;
        }
        req->nr_flags = nmr->nr_flags & (~NR_REG_MASK);
        if (nmr->nr_ringid & NETMAP_NO_TX_POLL) {
                req->nr_flags |= NR_NO_TX_POLL;
        }
        if (nmr->nr_ringid & NETMAP_DO_RX_POLL) {
                req->nr_flags |= NR_DO_RX_POLL;
        }
        /* nmr->nr_arg1 (nr_pipes) ignored */
        req->nr_extra_bufs = nmr->nr_arg3;

        return 0;
}

/* Convert the legacy 'nmr' struct into one of the nmreq_xyz structs
 * (new API). The new struct is dynamically allocated. */
static struct nmreq_header *
nmreq_from_legacy(struct nmreq *nmr, u_long ioctl_cmd)
{
        struct nmreq_header *hdr = nm_os_malloc(sizeof(*hdr));

        if (hdr == NULL) {
                goto oom;
        }

        /* Sanitize nmr->nr_name by adding the string terminator. */
        if (ioctl_cmd == NIOCGINFO || ioctl_cmd == NIOCREGIF) {
                nmr->nr_name[sizeof(nmr->nr_name) - 1] = '\0';
        }

        /* First prepare the request header. */
        hdr->nr_version = NETMAP_API; /* new API */
        strlcpy(hdr->nr_name, nmr->nr_name, sizeof(nmr->nr_name));
        hdr->nr_options = (uintptr_t)NULL;
        hdr->nr_body = (uintptr_t)NULL;

        switch (ioctl_cmd) {
        case NIOCREGIF: {
                switch (nmr->nr_cmd) {
                case 0: {
                        /* Regular NIOCREGIF operation. */
                        struct nmreq_register *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = NETMAP_REQ_REGISTER;
                        if (nmreq_register_from_legacy(nmr, hdr, req)) {
                                goto oom;
                        }
                        break;
                }
                case NETMAP_BDG_ATTACH: {
                        struct nmreq_vale_attach *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = NETMAP_REQ_VALE_ATTACH;
                        if (nmreq_register_from_legacy(nmr, hdr, &req->reg)) {
                                goto oom;
                        }
                        /* Fix nr_mode, starting from nr_arg1. */
                        if (nmr->nr_arg1 & NETMAP_BDG_HOST) {
                                req->reg.nr_mode = NR_REG_NIC_SW;
                        } else {
                                req->reg.nr_mode = NR_REG_ALL_NIC;
                        }
                        break;
                }
                case NETMAP_BDG_DETACH: {
                        hdr->nr_reqtype = NETMAP_REQ_VALE_DETACH;
                        hdr->nr_body = (uintptr_t)nm_os_malloc(sizeof(struct nmreq_vale_detach));
                        break;
                }
                case NETMAP_BDG_VNET_HDR:
                case NETMAP_VNET_HDR_GET: {
                        struct nmreq_port_hdr *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = (nmr->nr_cmd == NETMAP_BDG_VNET_HDR) ?
                                NETMAP_REQ_PORT_HDR_SET : NETMAP_REQ_PORT_HDR_GET;
                        req->nr_hdr_len = nmr->nr_arg1;
                        break;
                }
                case NETMAP_BDG_NEWIF : {
                        struct nmreq_vale_newif *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = NETMAP_REQ_VALE_NEWIF;
                        req->nr_tx_slots = nmr->nr_tx_slots;
                        req->nr_rx_slots = nmr->nr_rx_slots;
                        req->nr_tx_rings = nmr->nr_tx_rings;
                        req->nr_rx_rings = nmr->nr_rx_rings;
                        req->nr_mem_id = nmr->nr_arg2;
                        break;
                }
                case NETMAP_BDG_DELIF: {
                        hdr->nr_reqtype = NETMAP_REQ_VALE_DELIF;
                        break;
                }
                case NETMAP_BDG_POLLING_ON:
                case NETMAP_BDG_POLLING_OFF: {
                        struct nmreq_vale_polling *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = (nmr->nr_cmd == NETMAP_BDG_POLLING_ON) ?
                                NETMAP_REQ_VALE_POLLING_ENABLE :
                                NETMAP_REQ_VALE_POLLING_DISABLE;
                        switch (nmr->nr_flags & NR_REG_MASK) {
                        default:
                                req->nr_mode = 0; /* invalid */
                                break;
                        case NR_REG_ONE_NIC:
                                req->nr_mode = NETMAP_POLLING_MODE_MULTI_CPU;
                                break;
                        case NR_REG_ALL_NIC:
                                req->nr_mode = NETMAP_POLLING_MODE_SINGLE_CPU;
                                break;
                        }
                        req->nr_first_cpu_id = nmr->nr_ringid & NETMAP_RING_MASK;
                        req->nr_num_polling_cpus = nmr->nr_arg1;
                        break;
                }
                case NETMAP_PT_HOST_CREATE:
                case NETMAP_PT_HOST_DELETE: {
                        nm_prerr("Netmap passthrough not supported yet");
                        return NULL;
                        break;
                }
                }
                break;
        }
        case NIOCGINFO: {
                if (nmr->nr_cmd == NETMAP_BDG_LIST) {
                        struct nmreq_vale_list *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = NETMAP_REQ_VALE_LIST;
                        req->nr_bridge_idx = nmr->nr_arg1;
                        req->nr_port_idx = nmr->nr_arg2;
                } else {
                        /* Regular NIOCGINFO. */
                        struct nmreq_port_info_get *req = nm_os_malloc(sizeof(*req));
                        if (!req) { goto oom; }
                        hdr->nr_body = (uintptr_t)req;
                        hdr->nr_reqtype = NETMAP_REQ_PORT_INFO_GET;
                        req->nr_memsize = nmr->nr_memsize;
                        req->nr_tx_slots = nmr->nr_tx_slots;
                        req->nr_rx_slots = nmr->nr_rx_slots;
                        req->nr_tx_rings = nmr->nr_tx_rings;
                        req->nr_rx_rings = nmr->nr_rx_rings;
                        req->nr_host_tx_rings = 0;
                        req->nr_host_rx_rings = 0;
                        req->nr_mem_id = nmr->nr_arg2;
                }
                break;
        }
        }

        return hdr;
oom:
        if (hdr) {
                if (hdr->nr_body) {
                        nm_os_free((void *)(uintptr_t)hdr->nr_body);
                }
                nm_os_free(hdr);
        }
        nm_prerr("Failed to allocate memory for nmreq_xyz struct");

        return NULL;
}

static void
nmreq_register_to_legacy(const struct nmreq_register *req, struct nmreq *nmr)
{
        nmr->nr_offset = req->nr_offset;
        nmr->nr_memsize = req->nr_memsize;
        nmr->nr_tx_slots = req->nr_tx_slots;
        nmr->nr_rx_slots = req->nr_rx_slots;
        nmr->nr_tx_rings = req->nr_tx_rings;
        nmr->nr_rx_rings = req->nr_rx_rings;
        nmr->nr_arg2 = req->nr_mem_id;
        nmr->nr_arg3 = req->nr_extra_bufs;
}

/* Convert a nmreq_xyz struct (new API) to the legacy 'nmr' struct.
 * It also frees the nmreq_xyz struct, as it was allocated by
 * nmreq_from_legacy(). */
static int
nmreq_to_legacy(struct nmreq_header *hdr, struct nmreq *nmr)
{
        int ret = 0;

        /* We only write-back the fields that the user expects to be
         * written back. */
        switch (hdr->nr_reqtype) {
        case NETMAP_REQ_REGISTER: {
                struct nmreq_register *req =
                        (struct nmreq_register *)(uintptr_t)hdr->nr_body;
                nmreq_register_to_legacy(req, nmr);
                break;
        }
        case NETMAP_REQ_PORT_INFO_GET: {
                struct nmreq_port_info_get *req =
                        (struct nmreq_port_info_get *)(uintptr_t)hdr->nr_body;
                nmr->nr_memsize = req->nr_memsize;
                nmr->nr_tx_slots = req->nr_tx_slots;
                nmr->nr_rx_slots = req->nr_rx_slots;
                nmr->nr_tx_rings = req->nr_tx_rings;
                nmr->nr_rx_rings = req->nr_rx_rings;
                nmr->nr_arg2 = req->nr_mem_id;
                break;
        }
        case NETMAP_REQ_VALE_ATTACH: {
                struct nmreq_vale_attach *req =
                        (struct nmreq_vale_attach *)(uintptr_t)hdr->nr_body;
                nmreq_register_to_legacy(&req->reg, nmr);
                break;
        }
        case NETMAP_REQ_VALE_DETACH: {
                break;
        }
        case NETMAP_REQ_VALE_LIST: {
                struct nmreq_vale_list *req =
                        (struct nmreq_vale_list *)(uintptr_t)hdr->nr_body;
                strlcpy(nmr->nr_name, hdr->nr_name, sizeof(nmr->nr_name));
                nmr->nr_arg1 = req->nr_bridge_idx;
                nmr->nr_arg2 = req->nr_port_idx;
                break;
        }
        case NETMAP_REQ_PORT_HDR_SET:
        case NETMAP_REQ_PORT_HDR_GET: {
                struct nmreq_port_hdr *req =
                        (struct nmreq_port_hdr *)(uintptr_t)hdr->nr_body;
                nmr->nr_arg1 = req->nr_hdr_len;
                break;
        }
        case NETMAP_REQ_VALE_NEWIF: {
                struct nmreq_vale_newif *req =
                        (struct nmreq_vale_newif *)(uintptr_t)hdr->nr_body;
                nmr->nr_tx_slots = req->nr_tx_slots;
                nmr->nr_rx_slots = req->nr_rx_slots;
                nmr->nr_tx_rings = req->nr_tx_rings;
                nmr->nr_rx_rings = req->nr_rx_rings;
                nmr->nr_arg2 = req->nr_mem_id;
                break;
        }
        case NETMAP_REQ_VALE_DELIF:
        case NETMAP_REQ_VALE_POLLING_ENABLE:
        case NETMAP_REQ_VALE_POLLING_DISABLE: {
                break;
        }
        }

        return ret;
}

int
netmap_ioctl_legacy(struct netmap_priv_d *priv, u_long cmd, caddr_t data,
                        struct thread *td)
{
        int error = 0;

        switch (cmd) {
        case NIOCGINFO:
        case NIOCREGIF: {
                /* Request for the legacy control API. Convert it to a
                 * NIOCCTRL request. */
                struct nmreq *nmr = (struct nmreq *) data;
                struct nmreq_header *hdr;

                if (nmr->nr_version < 14) {
                        nm_prerr("Minimum supported API is 14 (requested %u)",
                            nmr->nr_version);
                        return EINVAL;
                }
                hdr = nmreq_from_legacy(nmr, cmd);
                if (hdr == NULL) { /* out of memory */
                        return ENOMEM;
                }
                error = netmap_ioctl(priv, NIOCCTRL, (caddr_t)hdr, td,
                                        /*nr_body_is_user=*/0);
                if (error == 0) {
                        nmreq_to_legacy(hdr, nmr);
                }
                if (hdr->nr_body) {
                        nm_os_free((void *)(uintptr_t)hdr->nr_body);
                }
                nm_os_free(hdr);
                break;
        }
#ifdef WITH_VALE
        case NIOCCONFIG: {
                struct nm_ifreq *nr = (struct nm_ifreq *)data;
                error = netmap_bdg_config(nr);
                break;
        }
#endif
#ifdef __FreeBSD__
        case FIONBIO:
        case FIOASYNC:
                /* FIONBIO/FIOASYNC are no-ops. */
                break;

        case BIOCIMMEDIATE:
        case BIOCGHDRCMPLT:
        case BIOCSHDRCMPLT:
        case BIOCSSEESENT:
                /* Ignore these commands. */
                break;

        default:        /* allow device-specific ioctls */
            {
                struct nmreq *nmr = (struct nmreq *)data;
                if_t ifp = ifunit_ref(nmr->nr_name);
                if (ifp == NULL) {
                        error = ENXIO;
                } else {
                        struct socket so;

                        bzero(&so, sizeof(so));
                        so.so_vnet = if_getvnet(ifp);
                        // so->so_proto not null.
                        error = ifioctl(&so, cmd, data, td);
                        if_rele(ifp);
                }
                break;
            }

#else /* linux */
        default:
                error = EOPNOTSUPP;
#endif /* linux */
        }

        return error;
}