/* Copyright (C) 2022 Open Information Security Foundation

 *

 * You can copy, redistribute or modify this Program under the terms of

 * the GNU General Public License version 2 as published by the Free

 * Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * version 2 along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

 * 02110-1301, USA.

 */

/**

 * \ingroup afxdppacket

 *

 * @{

 */

/**

 * \file

 *

 * \author Richard McConnell <richard_mcconnell@rapid7.com>

 *

 * AF_XDP socket runmode

 *

 */

#define SC_PCAP_DONT_INCLUDE_PCAP_H  1

#include "suricata-common.h"

#include "tm-threads.h"

#include "conf.h"

#include "runmodes.h"

#include "runmode-af-xdp.h"

#include "output.h"

#include "log-httplog.h"

#include "detect-engine-mpm.h"

#include "alert-fastlog.h"

#include "alert-debuglog.h"

#include "flow-bypass.h"

#include "util-conf.h"

#include "util-debug.h"

#include "util-time.h"

#include "util-cpu.h"

#include "util-affinity.h"

#include "util-device-private.h"

#include "util-runmodes.h"

#include "util-ioctl.h"

#include "util-ebpf.h"

#include "util-byte.h"

#include "source-af-xdp.h"

#ifdef HAVE_AF_XDP

#include <linux/if_xdp.h>

#include <linux/if_link.h>

#include <xdp/xsk.h>

#endif

const char *RunModeAFXDPGetDefaultMode(void)

{

    return "workers";

}

void RunModeIdsAFXDPRegister(void)

{

    RunModeRegisterNewRunMode(RUNMODE_AFXDP_DEV, "single", "Single threaded af-xdp mode",

            RunModeIdsAFXDPSingle, NULL);

    RunModeRegisterNewRunMode(RUNMODE_AFXDP_DEV, "workers",

            "Workers af-xdp mode, each thread does all"

            " tasks from acquisition to logging",

            RunModeIdsAFXDPWorkers, NULL);

}

#ifdef HAVE_AF_XDP

#define DEFAULT_BUSY_POLL_TIME    20

#define DEFAULT_BUSY_POLL_BUDGET  64

#define DEFAULT_GRO_FLUSH_TIMEOUT 2000000

#define DEFAULT_NAPI_HARD_IRQS    2

static void AFXDPDerefConfig(void *conf)

{

    AFXDPIfaceConfig *pfp = (AFXDPIfaceConfig *)conf;

    /* Pcap config is used only once but cost of this low. */

    if (SC_ATOMIC_SUB(pfp->ref, 1) <= 1) {

        SCFree(pfp);

    }

}

static TmEcode ConfigSetThreads(AFXDPIfaceConfig *aconf, const char *entry_str)

{

    SCEnter();

    const char *active_runmode = RunmodeGetActive();

    if (active_runmode && !strcmp("single", active_runmode)) {

        aconf->threads = 1;

        SCReturnInt(0);

    }

    if (entry_str == NULL) {

        SCLogError("Number of threads for interface \"%s\" not specified", aconf->iface);

        SCReturnInt(TM_ECODE_FAILED);

    }

    const int nr_queues = GetIfaceRSSQueuesNum(aconf->iface);

    if (strcmp(entry_str, "auto") == 0) {

        const int nr_cores = (int)UtilCpuGetNumProcessorsOnline();

        /* Threads limited to MIN(cores vs queues) */

        aconf->threads = (nr_cores <= nr_queues) ? nr_cores : nr_queues;

        const char *sys_type = nr_cores <= nr_queues ? "cores" : "queues";

        SCLogPerf("%u %s, so using %u threads", aconf->threads, sys_type, aconf->threads);

        SCReturnInt(TM_ECODE_OK);

    }

    if (StringParseInt32(&aconf->threads, 10, 0, entry_str) < 0) {

        SCLogError("Threads entry for interface %s contain non-numerical characters - \"%s\"",

                aconf->iface, entry_str);

        SCReturnInt(TM_ECODE_FAILED);

    }

    if (aconf->threads < 0) {

        SCLogError("Interface %s has a negative number of threads", aconf->iface);

        SCReturnInt(TM_ECODE_FAILED);

    }

    if (aconf->threads > nr_queues) {

        SCLogWarning(

                "Selected threads greater than configured queues, using: %d thread(s)", nr_queues);

        aconf->threads = nr_queues;

    }

    SCReturnInt(TM_ECODE_OK);

}

/**

 * \brief extract information from config file

 *

 * The returned structure will be freed by the thread init function.

 * This is thus necessary to copy the structure before giving it

 * to thread or to reparse the file for each thread (and thus have

 * new structure.

 *

 * \return a AFXDPIfaceConfig corresponding to the interface name

 */

static void *ParseAFXDPConfig(const char *iface)

{

    const char *confstr = NULL;

    SCConfNode *if_root;

    SCConfNode *if_default = NULL;

    SCConfNode *af_xdp_node = NULL;

    int conf_val = 0;

    intmax_t conf_val_int = 0;

    int boolval = 0;

    if (iface == NULL) {

        return NULL;

    }

    AFXDPIfaceConfig *aconf = SCCalloc(1, sizeof(*aconf));

    if (unlikely(aconf == NULL)) {

        return NULL;

    }

    /* default/basic config setup */

    strlcpy(aconf->iface, iface, sizeof(aconf->iface));

    aconf->DerefFunc = AFXDPDerefConfig;

    aconf->threads = 1;

    aconf->promisc = 1;

    aconf->enable_busy_poll = true;

    aconf->busy_poll_time = DEFAULT_BUSY_POLL_TIME;

    aconf->busy_poll_budget = DEFAULT_BUSY_POLL_BUDGET;

    aconf->mode = XDP_FLAGS_UPDATE_IF_NOEXIST;

    aconf->gro_flush_timeout = DEFAULT_GRO_FLUSH_TIMEOUT;

    aconf->napi_defer_hard_irqs = DEFAULT_NAPI_HARD_IRQS;

    aconf->mem_alignment = XSK_UMEM__DEFAULT_FLAGS;

    /* Find initial node */

    af_xdp_node = SCConfGetNode("af-xdp");

    if (af_xdp_node == NULL) {

        SCLogInfo("unable to find af-xdp config using default values");

        goto finalize;

    }

    if_root = ConfFindDeviceConfig(af_xdp_node, iface);

    if_default = ConfFindDeviceConfig(af_xdp_node, "default");

    if (if_root == NULL && if_default == NULL) {

        SCLogInfo("unable to find af-xdp config for "

                  "interface \"%s\" or \"default\", using default values",

                iface);

        goto finalize;

    }

    /* If there is no setting for current interface use default one as main iface */

    if (if_root == NULL) {

        if_root = if_default;

        if_default = NULL;

    }

    /* Threading */

    confstr = "auto";

    (void)SCConfGetChildValueWithDefault(if_root, if_default, "threads", &confstr);

    if (ConfigSetThreads(aconf, confstr) != TM_ECODE_OK) {

        aconf->DerefFunc(aconf);

        return NULL;

    }

    SC_ATOMIC_RESET(aconf->ref);

    (void)SC_ATOMIC_ADD(aconf->ref, aconf->threads);

    /* Promisc Mode */

    (void)SCConfGetChildValueBoolWithDefault(if_root, if_default, "disable-promisc", &boolval);

    if (boolval) {

        SCLogConfig("Disabling promiscuous mode on iface %s", aconf->iface);

        aconf->promisc = 0;

    }

#ifdef HAVE_AF_XDP

    /* AF_XDP socket mode options */

    if (SCConfGetChildValueWithDefault(if_root, if_default, "force-xdp-mode", &confstr) == 1) {

        if (strncasecmp(confstr, "drv", 3) == 0) {

            aconf->mode |= XDP_FLAGS_DRV_MODE;

        } else if (strncasecmp(confstr, "skb", 3) == 0) {

            aconf->mode |= XDP_FLAGS_SKB_MODE;

        } else if (strncasecmp(confstr, "none", 4) == 0) {

        } else {

            SCLogWarning("Incorrect af-xdp xdp-mode setting, default (none) shall be applied");

        }

    }

    /* copy and zerocopy binding options */

    if (SCConfGetChildValueWithDefault(if_root, if_default, "force-bind-mode", &confstr) == 1) {

        if (strncasecmp(confstr, "zero", 4) == 0) {

            aconf->bind_flags |= XDP_ZEROCOPY;

        } else if (strncasecmp(confstr, "copy", 4) == 0) {

            aconf->bind_flags |= XDP_COPY;

        } else if (strncasecmp(confstr, "none", 4) == 0) {

        } else {

            SCLogWarning("Incorrect af-xdp copy-mode setting, default (none) shall be applied");

        }

    }

    /* memory alignment mode selection */

    if (SCConfGetChildValueWithDefault(if_root, if_default, "mem-unaligned", &confstr) == 1) {

        if (strncasecmp(confstr, "yes", 3) == 0) {

            aconf->mem_alignment = XDP_UMEM_UNALIGNED_CHUNK_FLAG;

        }

    }

    /* Busy polling options */

    if (SCConfGetChildValueBoolWithDefault(if_root, if_default, "enable-busy-poll", &conf_val) ==

            1) {

        if (conf_val == 0) {

            aconf->enable_busy_poll = false;

        }

    }

    if (aconf->enable_busy_poll) {

        if (SCConfGetChildValueIntWithDefault(

                    if_root, if_default, "busy-poll-time", &conf_val_int) == 1) {

            if (conf_val_int) {

                aconf->busy_poll_time = conf_val_int;

            }

        }

        if (SCConfGetChildValueIntWithDefault(

                    if_root, if_default, "busy-poll-budget", &conf_val_int) == 1) {

            if (conf_val_int) {

                aconf->busy_poll_budget = conf_val_int;

            }

        }

        /* 0 value is valid for these Linux tunable's */

        if (SCConfGetChildValueIntWithDefault(

                    if_root, if_default, "gro-flush-timeout", &conf_val_int) == 1) {

            aconf->gro_flush_timeout = conf_val_int;

        }

        if (SCConfGetChildValueIntWithDefault(

                    if_root, if_default, "napi-defer-hard-irq", &conf_val_int) == 1) {

            aconf->napi_defer_hard_irqs = conf_val_int;

        }

    }

#endif

finalize:

    if (LiveGetOffload() == 0) {

        if (GetIfaceOffloading(iface, 0, 1) == 1) {

            SCLogWarning("Using AF_XDP with offloading activated leads to capture problems");

        }

    } else {

        DisableIfaceOffloading(LiveGetDevice(iface), 0, 1);

    }

    return aconf;

}

static int AFXDPConfigGetThreadsCount(void *conf)

{

    if (conf == NULL)

        FatalError("Configuration file is NULL");

    AFXDPIfaceConfig *afxdp_conf = (AFXDPIfaceConfig *)conf;

    return afxdp_conf->threads;

}

#endif /* HAVE_AF_XDP */

/**

 * \brief Single thread version of the AF_XDP processing.

 */

int RunModeIdsAFXDPSingle(void)

{

    SCEnter();

#ifdef HAVE_AF_XDP

    int ret;

    const char *live_dev = NULL;

    TimeModeSetLive();

    (void)SCConfGet("af-xdp.live-interface", &live_dev);

    if (AFXDPQueueProtectionInit() != TM_ECODE_OK) {

        FatalError("Unable to init AF_XDP queue protection.");

    }

    ret = RunModeSetLiveCaptureSingle(ParseAFXDPConfig, AFXDPConfigGetThreadsCount, "ReceiveAFXDP",

            "DecodeAFXDP", thread_name_single, live_dev);

    if (ret != 0) {

        FatalError("Unable to start runmode");

    }

    SCLogDebug("RunModeIdsAFXDPSingle initialised");

#endif /* HAVE_AF_XDP */

    SCReturnInt(0);

}

/**

 * \brief Workers version of the AF_XDP processing.

 *

 * Start N threads with each thread doing all the work.

 *

 */

int RunModeIdsAFXDPWorkers(void)

{

    SCEnter();

#ifdef HAVE_AF_XDP

    int ret;

    const char *live_dev = NULL;

    TimeModeSetLive();

    (void)SCConfGet("af-xdp.live-interface", &live_dev);

    if (AFXDPQueueProtectionInit() != TM_ECODE_OK) {

        FatalError("Unable to init AF_XDP queue protection.");

    }

    ret = RunModeSetLiveCaptureWorkers(ParseAFXDPConfig, AFXDPConfigGetThreadsCount, "ReceiveAFXDP",

            "DecodeAFXDP", thread_name_workers, live_dev);

    if (ret != 0) {

        FatalError("Unable to start runmode");

    }

    SCLogDebug("RunModeIdsAFXDPWorkers initialised");

#endif /* HAVE_AF_XDP */

    SCReturnInt(0);

}

/**

 * @}

 */