/*
 * Copyright (c) 2012-2021 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#include <kern/locks.h>
#include <kern/zalloc.h>

#include <sys/types.h>
#include <sys/kernel_types.h>
#include <sys/kauth.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/proc.h>

#include <net/if.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/bpf.h>
#include <net/net_osdep.h>
#include <net/pktap.h>

#include <netinet/in_pcb.h>
#include <netinet/tcp.h>
#include <netinet/tcp_var.h>
#define _IP_VHL
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>

#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>

#include <libkern/OSAtomic.h>

#include <kern/debug.h>

#include <os/log.h>

#include <sys/mcache.h>

#include <string.h>
#include <stdbool.h>


struct kern_pktap_filter {
	uint32_t        filter_op;
	uint32_t        filter_param;
	union {
		uint32_t        _filter_if_type;
		char            _filter_if_name[PKTAP_IFXNAMESIZE];
	} param_;
	size_t          filter_ifname_len;
	bool            filter_ifname_prefix_match;
};

extern struct inpcbinfo ripcbinfo;

struct pktap_softc {
	LIST_ENTRY(pktap_softc)         pktp_link;
	uint32_t                        pktp_unit;
	uint32_t                        pktp_dlt_raw_count;
	uint32_t                        pktp_dlt_pkttap_count;
	struct ifnet                    *pktp_ifp;
	struct kern_pktap_filter        pktp_filters[PKTAP_MAX_FILTERS];
};

#ifndef PKTAP_DEBUG
#define PKTAP_DEBUG 0
#endif /* PKTAP_DEBUG */

#define PKTAP_FILTER_OK 0               /* Packet passes filter checks */
#define PKTAP_FILTER_SKIP 1             /* Do not tap this packet */

static int pktap_inited = 0;

SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, IFT_PKTAP, pktap,
    CTLFLAG_RW  | CTLFLAG_LOCKED, 0, "pktap virtual interface");

uint32_t pktap_total_tap_count = 0;
SYSCTL_UINT(_net_link_pktap, OID_AUTO, total_tap_count,
    CTLFLAG_RD | CTLFLAG_LOCKED, &pktap_total_tap_count, 0, "");

static u_int64_t pktap_count_unknown_if_type = 0;
SYSCTL_QUAD(_net_link_pktap, OID_AUTO, count_unknown_if_type,
    CTLFLAG_RD | CTLFLAG_LOCKED, &pktap_count_unknown_if_type, "");

static int pktap_log = 0;
SYSCTL_INT(_net_link_pktap, OID_AUTO, log,
    CTLFLAG_RW | CTLFLAG_LOCKED, &pktap_log, 0, "");

#define PKTAP_LOG(mask, fmt, ...) \
do { \
	if (__improbable(pktap_log & mask)) \
	        os_log(OS_LOG_DEFAULT, "%s:%d " fmt, __FUNCTION__, __LINE__, ##__VA_ARGS__); \
} while (false)

#define PKTP_LOG_FUNC 0x01
#define PKTP_LOG_FILTER 0x02
#define PKTP_LOG_INPUT 0x04
#define PKTP_LOG_OUTPUT 0x08
#define PKTP_LOG_ERROR 0x10
#define PKTP_LOG_NOPCB 0x20

/*
 * pktap_lck_rw protects the global list of pktap interfaces
 */
static LCK_GRP_DECLARE(pktap_lck_grp, "pktap");
#if PKTAP_DEBUG
static LCK_ATTR_DECLARE(pktap_lck_attr, LCK_ATTR_DEBUG, 0);
#else
static LCK_ATTR_DECLARE(pktap_lck_attr, 0, 0);
#endif
static LCK_RW_DECLARE_ATTR(pktap_lck_rw, &pktap_lck_grp, &pktap_lck_attr);


static LIST_HEAD(pktap_list, pktap_softc) pktap_list =
    LIST_HEAD_INITIALIZER(pktap_list);

int pktap_clone_create(struct if_clone *, u_int32_t, void *);
int pktap_clone_destroy(struct ifnet *);

#define PKTAP_MAXUNIT   IF_MAXUNIT
#define PKTAP_ZONE_MAX_ELEM     MIN(IFNETS_MAX, PKTAP_MAXUNIT)

static struct if_clone pktap_cloner =
    IF_CLONE_INITIALIZER(PKTAP_IFNAME,
    pktap_clone_create,
    pktap_clone_destroy,
    0,
    PKTAP_MAXUNIT);

errno_t pktap_if_output(ifnet_t, mbuf_t);
errno_t pktap_demux(ifnet_t, mbuf_t, char *, protocol_family_t *);
errno_t pktap_add_proto(ifnet_t, protocol_family_t,
    const struct ifnet_demux_desc *, u_int32_t);
errno_t pktap_del_proto(ifnet_t, protocol_family_t);
errno_t pktap_getdrvspec(ifnet_t, struct ifdrv64 *);
errno_t pktap_setdrvspec(ifnet_t, struct ifdrv64 *);
errno_t pktap_ioctl(ifnet_t, unsigned long cmd, void *__sized_by(IOCPARM_LEN(cmd)));
void pktap_detach(ifnet_t);
int pktap_filter_evaluate(struct pktap_softc *, struct ifnet *);
void pktap_bpf_tap(struct ifnet *, protocol_family_t, struct mbuf *,
    u_int32_t, u_int32_t, int);
errno_t pktap_tap_callback(ifnet_t, u_int32_t, bpf_tap_mode);

static void
pktap_hexdump(int mask, void *__sized_by(len) addr, size_t len)
{
	unsigned char *buf = addr;
	size_t i;

	if (!(pktap_log & mask)) {
		return;
	}

	for (i = 0; i < len; i++) {
		unsigned char  h = (buf[i] & 0xf0) >> 4;
		unsigned char  l = buf[i] & 0x0f;

		if (i != 0) {
			if (i % 32 == 0) {
				printf("\n");
			} else if (i % 4 == 0) {
				printf(" ");
			}
		}
		printf("%c%c",
		    h < 10 ? h + '0' : h - 10 + 'a',
		    l < 10 ? l + '0' : l - 10 + 'a');
	}
	if (i % 32 != 0) {
		printf("\n");
	}
}

#define ASSERT_OFFFSETOF_FIELD(s1, s2, f) \
	static_assert(offsetof(struct s1, f) == offsetof(struct s2, f))

__private_extern__ void
pktap_init(void)
{
	int error = 0;

	ASSERT_OFFFSETOF_FIELD(pktap_header, pktap_v2_hdr, pth_flags);

	/* Make sure we're called only once */
	VERIFY(pktap_inited == 0);

	pktap_inited = 1;

	LIST_INIT(&pktap_list);

	error = if_clone_attach(&pktap_cloner);
	if (error != 0) {
		panic("%s: if_clone_attach() failed, error %d",
		    __func__, error);
	}
}

__private_extern__ int
pktap_clone_create(struct if_clone *ifc, u_int32_t unit, __unused void *params)
{
	int error = 0;
	struct pktap_softc *__single pktap = NULL;
	struct ifnet_init_eparams if_init;

	PKTAP_LOG(PKTP_LOG_FUNC, "unit %u\n", unit);

	pktap = kalloc_type(struct pktap_softc, Z_WAITOK_ZERO_NOFAIL);
	pktap->pktp_unit = unit;

	/*
	 * By default accept packet from physical interfaces
	 */
	pktap->pktp_filters[0].filter_op = PKTAP_FILTER_OP_PASS;
	pktap->pktp_filters[0].filter_param = PKTAP_FILTER_PARAM_IF_TYPE;
	pktap->pktp_filters[0].filter_param_if_type = IFT_ETHER;

#if !XNU_TARGET_OS_OSX
	pktap->pktp_filters[1].filter_op = PKTAP_FILTER_OP_PASS;
	pktap->pktp_filters[1].filter_param = PKTAP_FILTER_PARAM_IF_TYPE;
	pktap->pktp_filters[1].filter_param_if_type = IFT_CELLULAR;
#else /* XNU_TARGET_OS_OSX */
	pktap->pktp_filters[1].filter_op = PKTAP_FILTER_OP_PASS;
	pktap->pktp_filters[1].filter_param = PKTAP_FILTER_PARAM_IF_TYPE;
	pktap->pktp_filters[1].filter_param_if_type = IFT_IEEE1394;
#endif /* XNU_TARGET_OS_OSX */

	pktap->pktp_filters[2].filter_op = PKTAP_FILTER_OP_PASS;
	pktap->pktp_filters[2].filter_param = PKTAP_FILTER_PARAM_IF_TYPE;
	pktap->pktp_filters[2].filter_param_if_type = IFT_OTHER;

	/*
	 * We do not use a set_bpf_tap() function as we rather rely on the more
	 * accurate callback passed to bpf_attach()
	 */
	bzero(&if_init, sizeof(if_init));
	if_init.ver = IFNET_INIT_CURRENT_VERSION;
	if_init.len = sizeof(if_init);
	if_init.flags = IFNET_INIT_LEGACY;
	if_init.name = __unsafe_null_terminated_from_indexable(ifc->ifc_name);
	if_init.unit = unit;
	if_init.type = IFT_PKTAP;
	if_init.family = IFNET_FAMILY_LOOPBACK;
	if_init.output = pktap_if_output;
	if_init.demux = pktap_demux;
	if_init.add_proto = pktap_add_proto;
	if_init.del_proto = pktap_del_proto;
	if_init.softc = pktap;
	if_init.ioctl = pktap_ioctl;
	if_init.detach = pktap_detach;

	error = ifnet_allocate_extended(&if_init, &pktap->pktp_ifp);
	if (error != 0) {
		printf("%s: ifnet_allocate failed, error %d\n",
		    __func__, error);
		goto done;
	}

	ifnet_set_flags(pktap->pktp_ifp, IFF_UP, IFF_UP);

	error = ifnet_attach(pktap->pktp_ifp, NULL);
	if (error != 0) {
		printf("%s: ifnet_attach failed - error %d\n", __func__, error);
		ifnet_release(pktap->pktp_ifp);
		goto done;
	}

	/* Attach DLT_PKTAP as the default DLT */
	bpf_attach(pktap->pktp_ifp, DLT_PKTAP, sizeof(struct pktap_header),
	    NULL, pktap_tap_callback);
	bpf_attach(pktap->pktp_ifp, DLT_RAW, 0, NULL, pktap_tap_callback);

	/* Take a reference and add to the global list */
	ifnet_reference(pktap->pktp_ifp);
	lck_rw_lock_exclusive(&pktap_lck_rw);
	LIST_INSERT_HEAD(&pktap_list, pktap, pktp_link);
	lck_rw_done(&pktap_lck_rw);
done:
	if (error != 0 && pktap != NULL) {
		kfree_type(struct pktap_softc, pktap);
	}
	return error;
}

__private_extern__ int
pktap_clone_destroy(struct ifnet *ifp)
{
	int error = 0;

	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);

	(void) ifnet_detach(ifp);

	return error;
}

/*
 * This function is called whenever a DLT is set on the interface:
 * - When interface is attached to a BPF device via BIOCSETIF for the
 *   default DLT
 * - Whenever a new DLT is selected via BIOCSDLT
 * - When the interface is detached from a BPF device (direction is zero)
 */
__private_extern__ errno_t
pktap_tap_callback(ifnet_t ifp, u_int32_t dlt, bpf_tap_mode direction)
{
	struct pktap_softc *__single pktap;

	pktap = ifp->if_softc;
	if (pktap == NULL) {
		printf("%s: if_softc is NULL for ifp %s\n", __func__,
		    ifp->if_xname);
		goto done;
	}
	switch (dlt) {
	case DLT_RAW:
		if (direction == 0) {
			if (pktap->pktp_dlt_raw_count > 0) {
				pktap->pktp_dlt_raw_count--;
				OSAddAtomic(-1, &pktap_total_tap_count);
			}
		} else {
			pktap->pktp_dlt_raw_count++;
			OSAddAtomic(1, &pktap_total_tap_count);
		}
		break;
	case DLT_PKTAP:
		if (direction == 0) {
			if (pktap->pktp_dlt_pkttap_count > 0) {
				pktap->pktp_dlt_pkttap_count--;
				OSAddAtomic(-1, &pktap_total_tap_count);
			}
		} else {
			pktap->pktp_dlt_pkttap_count++;
			OSAddAtomic(1, &pktap_total_tap_count);
		}
		break;
	}
done:
	/*
	 * Attachements count must be positive and we're in trouble
	 * if we have more that 2**31 attachements
	 */
	VERIFY(pktap_total_tap_count >= 0);

	return 0;
}

__private_extern__ errno_t
pktap_if_output(ifnet_t ifp, mbuf_t m)
{
	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);
	mbuf_freem(m);
	return ENOTSUP;
}

__private_extern__ errno_t
pktap_demux(ifnet_t ifp, __unused mbuf_t m, __unused char *header,
    __unused protocol_family_t *ppf)
{
	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);
	return ENOTSUP;
}

__private_extern__ errno_t
pktap_add_proto(__unused ifnet_t ifp, protocol_family_t pf,
    __unused const struct ifnet_demux_desc *dmx, __unused u_int32_t cnt)
{
	PKTAP_LOG(PKTP_LOG_FUNC, "%s pf %u\n", ifp->if_xname, pf);
	return 0;
}

__private_extern__ errno_t
pktap_del_proto(__unused ifnet_t ifp, __unused protocol_family_t pf)
{
	PKTAP_LOG(PKTP_LOG_FUNC, "%s pf %u\n", ifp->if_xname, pf);
	return 0;
}

__private_extern__ errno_t
pktap_getdrvspec(ifnet_t ifp, struct ifdrv64 *ifd)
{
	errno_t error = 0;
	struct pktap_softc *__single pktap;
	int i;

	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);

	pktap = ifp->if_softc;
	if (pktap == NULL) {
		error = ENOENT;
		printf("%s: pktap NULL - error %d\n", __func__, error);
		goto done;
	}

	switch (ifd->ifd_cmd) {
	case PKTP_CMD_FILTER_GET: {
		struct pktap_filter x_filters[PKTAP_MAX_FILTERS];

		bzero(&x_filters, sizeof(x_filters));

		if (ifd->ifd_len < PKTAP_MAX_FILTERS * sizeof(struct pktap_filter)) {
			printf("%s: PKTP_CMD_FILTER_GET ifd_len %llu too small - error %d\n",
			    __func__, ifd->ifd_len, error);
			error = EINVAL;
			break;
		}
		for (i = 0; i < PKTAP_MAX_FILTERS; i++) {
			struct kern_pktap_filter *pktap_filter = pktap->pktp_filters + i;
			struct pktap_filter *x_filter = x_filters + i;

			x_filter->filter_op = pktap_filter->filter_op;
			x_filter->filter_param = pktap_filter->filter_param;

			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_TYPE) {
				x_filter->filter_param_if_type = pktap_filter->filter_param_if_type;
			} else if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_NAME) {
				strbufcpy(x_filter->filter_param_if_name,
				    pktap_filter->filter_param_if_name);
			}
		}
		error = copyout(x_filters, CAST_USER_ADDR_T(ifd->ifd_data),
		    PKTAP_MAX_FILTERS * sizeof(struct pktap_filter));
		if (error) {
			printf("%s: PKTP_CMD_FILTER_GET copyout - error %d\n", __func__, error);
			goto done;
		}
		break;
	}
	case PKTP_CMD_TAP_COUNT: {
		uint32_t tap_count = pktap->pktp_dlt_raw_count + pktap->pktp_dlt_pkttap_count;

		if (ifd->ifd_len < sizeof(tap_count)) {
			printf("%s: PKTP_CMD_TAP_COUNT ifd_len %llu too small - error %d\n",
			    __func__, ifd->ifd_len, error);
			error = EINVAL;
			break;
		}
		error = copyout(&tap_count, CAST_USER_ADDR_T(ifd->ifd_data), sizeof(tap_count));
		if (error) {
			printf("%s: PKTP_CMD_TAP_COUNT copyout - error %d\n", __func__, error);
			goto done;
		}
		break;
	}
	default:
		error = EINVAL;
		break;
	}

done:
	return error;
}

__private_extern__ errno_t
pktap_setdrvspec(ifnet_t ifp, struct ifdrv64 *ifd)
{
	errno_t error = 0;
	struct pktap_softc *__single pktap;

	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);

	pktap = ifp->if_softc;
	if (pktap == NULL) {
		error = ENOENT;
		printf("%s: pktap NULL - error %d\n", __func__, error);
		goto done;
	}

	switch (ifd->ifd_cmd) {
	case PKTP_CMD_FILTER_SET: {
		struct pktap_filter user_filters[PKTAP_MAX_FILTERS];
		int i;
		int got_op_none = 0;

		if (ifd->ifd_len != PKTAP_MAX_FILTERS * sizeof(struct pktap_filter)) {
			printf("%s: PKTP_CMD_FILTER_SET bad ifd_len %llu - error %d\n",
			    __func__, ifd->ifd_len, error);
			error = EINVAL;
			break;
		}
		error = copyin(CAST_USER_ADDR_T(ifd->ifd_data), &user_filters, (size_t)ifd->ifd_len);
		if (error) {
			printf("%s: copyin - error %d\n", __func__, error);
			goto done;
		}
		/*
		 * Validate user provided parameters
		 */
		for (i = 0; i < PKTAP_MAX_FILTERS; i++) {
			struct pktap_filter *x_filter = user_filters + i;

			switch (x_filter->filter_op) {
			case PKTAP_FILTER_OP_NONE:
				/* Following entries must be PKTAP_FILTER_OP_NONE */
				got_op_none = 1;
				break;
			case PKTAP_FILTER_OP_PASS:
			case PKTAP_FILTER_OP_SKIP:
				/* Invalid after PKTAP_FILTER_OP_NONE */
				if (got_op_none) {
					error = EINVAL;
					break;
				}
				break;
			default:
				error = EINVAL;
				break;
			}
			if (error != 0) {
				break;
			}

			switch (x_filter->filter_param) {
			case PKTAP_FILTER_OP_NONE:
				if (x_filter->filter_op != PKTAP_FILTER_OP_NONE) {
					error = EINVAL;
					break;
				}
				break;

			/*
			 * Do not allow to tap a pktap from a pktap
			 */
			case PKTAP_FILTER_PARAM_IF_TYPE:
				if (x_filter->filter_param_if_type == IFT_PKTAP ||
				    x_filter->filter_param_if_type > 0xff) {
					error = EINVAL;
					break;
				}
				break;

			case PKTAP_FILTER_PARAM_IF_NAME:
				if (strlcmp(x_filter->filter_param_if_name, PKTAP_IFNAME,
				    strlen(PKTAP_IFNAME)) == 0) {
					error = EINVAL;
					break;
				}
				break;

			default:
				error = EINVAL;
				break;
			}
			if (error != 0) {
				break;
			}
		}
		if (error != 0) {
			break;
		}
		for (i = 0; i < PKTAP_MAX_FILTERS; i++) {
			struct kern_pktap_filter *pktap_filter = pktap->pktp_filters + i;
			struct pktap_filter *x_filter = user_filters + i;

			pktap_filter->filter_op = x_filter->filter_op;
			pktap_filter->filter_param = x_filter->filter_param;

			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_TYPE) {
				pktap_filter->filter_param_if_type = x_filter->filter_param_if_type;
			} else if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_NAME) {
				size_t len;

				strbufcpy(pktap_filter->filter_param_if_name,
				    x_filter->filter_param_if_name);
				/*
				 * If name does not end with a number then it's a "wildcard" match
				 * where we compare the prefix of the interface name
				 */
				len = strbuflen(pktap_filter->filter_param_if_name);
				if (pktap_filter->filter_param_if_name[len - 1] < '0' ||
				    pktap_filter->filter_param_if_name[len - 1] > '9') {
					pktap_filter->filter_ifname_prefix_match = true;
				} else {
					pktap_filter->filter_ifname_prefix_match = false;
				}
				pktap_filter->filter_ifname_len = len;
			}
		}
		break;
	}
	default:
		error = EINVAL;
		break;
	}

done:
	return error;
}

__private_extern__ errno_t
pktap_ioctl(ifnet_t ifp, unsigned long cmd, void *__sized_by(IOCPARM_LEN(cmd)) data)
{
	errno_t error = 0;

	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);

	if ((cmd & IOC_IN)) {
		error = kauth_authorize_generic(kauth_cred_get(), KAUTH_GENERIC_ISSUSER);
		if (error) {
			PKTAP_LOG(PKTP_LOG_ERROR,
			    "%s: kauth_authorize_generic(KAUTH_GENERIC_ISSUSER) - error %d\n",
			    __func__, error);
			goto done;
		}
	}

	switch (cmd) {
	case SIOCGDRVSPEC32: {
		struct ifdrv64 ifd;
		struct ifdrv32 *ifd32 = (struct ifdrv32 *)data;

		memcpy(ifd.ifd_name, ifd32->ifd_name, sizeof(ifd.ifd_name));
		ifd.ifd_cmd = ifd32->ifd_cmd;
		ifd.ifd_len = ifd32->ifd_len;
		ifd.ifd_data = ifd32->ifd_data;

		error = pktap_getdrvspec(ifp, &ifd);

		break;
	}
	case SIOCGDRVSPEC64: {
		struct ifdrv64 *ifd64 = (struct ifdrv64 *)data;

		error = pktap_getdrvspec(ifp, ifd64);

		break;
	}
	case SIOCSDRVSPEC32: {
		struct ifdrv64 ifd;
		struct ifdrv32 *ifd32 = (struct ifdrv32 *)data;

		memcpy(ifd.ifd_name, ifd32->ifd_name, sizeof(ifd.ifd_name));
		ifd.ifd_cmd = ifd32->ifd_cmd;
		ifd.ifd_len = ifd32->ifd_len;
		ifd.ifd_data = ifd32->ifd_data;

		error = pktap_setdrvspec(ifp, &ifd);
		break;
	}
	case SIOCSDRVSPEC64: {
		struct ifdrv64 *ifd64 = (struct ifdrv64 *)data;

		error = pktap_setdrvspec(ifp, ifd64);

		break;
	}
	default:
		error = ENOTSUP;
		break;
	}
done:
	return error;
}

__private_extern__ void
pktap_detach(ifnet_t ifp)
{
	struct pktap_softc *__single pktap;

	PKTAP_LOG(PKTP_LOG_FUNC, "%s\n", ifp->if_xname);

	lck_rw_lock_exclusive(&pktap_lck_rw);

	pktap = ifp->if_softc;
	ifp->if_softc = NULL;
	LIST_REMOVE(pktap, pktp_link);

	lck_rw_done(&pktap_lck_rw);

	/* Drop reference as it's no more on the global list */
	ifnet_release(ifp);

	kfree_type(struct pktap_softc, pktap);
	/* This is for the reference taken by ifnet_attach() */
	(void) ifnet_release(ifp);
}

__private_extern__ int
pktap_filter_evaluate(struct pktap_softc *pktap, struct ifnet *ifp)
{
	int i;
	int result = PKTAP_FILTER_SKIP; /* Need positive matching rule to pass */
	int match = 0;

	for (i = 0; i < PKTAP_MAX_FILTERS; i++) {
		struct kern_pktap_filter *pktap_filter = pktap->pktp_filters + i;

		switch (pktap_filter->filter_op) {
		case PKTAP_FILTER_OP_NONE:
			match = 1;
			break;

		case PKTAP_FILTER_OP_PASS:
			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_TYPE) {
				if (pktap_filter->filter_param_if_type == 0 ||
				    ifp->if_type == pktap_filter->filter_param_if_type) {
					result = PKTAP_FILTER_OK;
					match = 1;
					PKTAP_LOG(PKTP_LOG_FILTER, "pass %s match type %u\n",
					    ifp->if_xname, pktap_filter->filter_param_if_type);
					break;
				}
			}
			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_NAME) {
				if (pktap_filter->filter_ifname_prefix_match == false) {
					match = !strlcmp(pktap_filter->filter_param_if_name,
					    ifp->if_xname,
					    pktap_filter->filter_ifname_len);
				} else {
					match = strprefix(ifp->if_xname,
					    __unsafe_forge_null_terminated(char *, pktap_filter->filter_param_if_name));
				}

				if (match) {
					result = PKTAP_FILTER_OK;
					PKTAP_LOG(PKTP_LOG_FILTER, "pass %s match name %s\n",
					    ifp->if_xname, pktap_filter->filter_param_if_name);
					break;
				}
			}
			break;

		case PKTAP_FILTER_OP_SKIP:
			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_TYPE) {
				if (pktap_filter->filter_param_if_type == 0 ||
				    ifp->if_type == pktap_filter->filter_param_if_type) {
					result = PKTAP_FILTER_SKIP;
					match = 1;
					PKTAP_LOG(PKTP_LOG_FILTER, "skip %s match type %u\n",
					    ifp->if_xname, pktap_filter->filter_param_if_type);
					break;
				}
			}
			if (pktap_filter->filter_param == PKTAP_FILTER_PARAM_IF_NAME) {
				if (pktap_filter->filter_ifname_prefix_match == false) {
					match = !strlcmp(pktap_filter->filter_param_if_name,
					    ifp->if_xname,
					    pktap_filter->filter_ifname_len);
				} else {
					match = strprefix(ifp->if_xname,
					    __unsafe_forge_null_terminated(char *, pktap_filter->filter_param_if_name));
				}
				if (match) {
					result = PKTAP_FILTER_SKIP;
					PKTAP_LOG(PKTP_LOG_FILTER, "skip %s match name %s\n",
					    ifp->if_xname, pktap_filter->filter_param_if_name);
					break;
				}
			}
			break;
		}
		if (match) {
			break;
		}
	}

	if (match == 0) {
		PKTAP_LOG(PKTP_LOG_FILTER, "%s no match\n",
		    ifp->if_xname);
	}
	return result;
}

static void
pktap_set_procinfo(struct pktap_header *hdr, struct so_procinfo *soprocinfo)
{
	hdr->pth_pid = soprocinfo->spi_pid;
	if (hdr->pth_comm[0] == 0) {
		proc_name(soprocinfo->spi_pid, hdr->pth_comm, MAXCOMLEN);
	}
	strbufcpy(hdr->pth_comm, soprocinfo->spi_proc_name);

	if (soprocinfo->spi_pid != 0) {
		uuid_copy(hdr->pth_uuid, soprocinfo->spi_uuid);
	}

	if (soprocinfo->spi_delegated != 0) {
		hdr->pth_flags |= PTH_FLAG_PROC_DELEGATED;
		hdr->pth_epid = soprocinfo->spi_epid;
		strbufcpy(hdr->pth_ecomm, soprocinfo->spi_e_proc_name);
		uuid_copy(hdr->pth_euuid, soprocinfo->spi_euuid);
	}
}

__private_extern__ void
pktap_finalize_proc_info(struct pktap_header *hdr)
{
	int found;
	struct so_procinfo soprocinfo;

	if (!(hdr->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
		return;
	}

	if (hdr->pth_ipproto == IPPROTO_TCP) {
		found = inp_findinpcb_procinfo(&tcbinfo, hdr->pth_flowid,
		    &soprocinfo);
	} else if (hdr->pth_ipproto == IPPROTO_UDP) {
		found = inp_findinpcb_procinfo(&udbinfo, hdr->pth_flowid,
		    &soprocinfo);
	} else {
		found = inp_findinpcb_procinfo(&ripcbinfo, hdr->pth_flowid,
		    &soprocinfo);
	}

	if (found == 1) {
		pktap_set_procinfo(hdr, &soprocinfo);
	}
}

static void
pktap_v2_set_procinfo(struct pktap_v2_hdr *pktap_v2_hdr,
    struct so_procinfo *soprocinfo)
{
	uint8_t *region = __unsafe_forge_bidi_indexable(uint8_t *,
	    pktap_v2_hdr,
	    pktap_v2_hdr->pth_length);
	pktap_v2_hdr->pth_pid = soprocinfo->spi_pid;

	if (soprocinfo->spi_pid != 0 && soprocinfo->spi_pid != -1) {
		if (pktap_v2_hdr->pth_comm_offset != 0) {
			char *ptr = __unsafe_forge_bidi_indexable(char *,
			    region + pktap_v2_hdr->pth_comm_offset,
			    PKTAP_MAX_COMM_SIZE);

			strbufcpy(ptr, PKTAP_MAX_COMM_SIZE, soprocinfo->spi_proc_name, PKTAP_MAX_COMM_SIZE);
		}
		if (pktap_v2_hdr->pth_uuid_offset != 0) {
			uuid_t *ptr = __unsafe_forge_bidi_indexable(uuid_t *,
			    region + pktap_v2_hdr->pth_uuid_offset,
			    sizeof(uuid_t));
			uuid_copy(*ptr, soprocinfo->spi_uuid);
		}
	}

	if (!(pktap_v2_hdr->pth_flags & PTH_FLAG_PROC_DELEGATED)) {
		return;
	}

	/*
	 * The effective UUID may be set independently from the effective pid
	 */
	if (soprocinfo->spi_delegated != 0) {
		pktap_v2_hdr->pth_flags |= PTH_FLAG_PROC_DELEGATED;
		pktap_v2_hdr->pth_e_pid = soprocinfo->spi_epid;

		if (soprocinfo->spi_pid != 0 && soprocinfo->spi_pid != -1 &&
		    pktap_v2_hdr->pth_e_comm_offset != 0) {
			char *ptr = __unsafe_forge_bidi_indexable(char *,
			    region + pktap_v2_hdr->pth_e_comm_offset,
			    PKTAP_MAX_COMM_SIZE);
			strbufcpy(ptr, PKTAP_MAX_COMM_SIZE, soprocinfo->spi_e_proc_name, PKTAP_MAX_COMM_SIZE);
		}
		if (pktap_v2_hdr->pth_e_uuid_offset != 0) {
			uuid_t *ptr = __unsafe_forge_bidi_indexable(uuid_t *,
			    region + pktap_v2_hdr->pth_e_uuid_offset,
			    sizeof(uuid_t));
			uuid_copy(*ptr, soprocinfo->spi_euuid);
		}
	}
}

__private_extern__ void
pktap_v2_finalize_proc_info(struct pktap_v2_hdr *pktap_v2_hdr)
{
	int found;
	struct so_procinfo soprocinfo;

	if (!(pktap_v2_hdr->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
		return;
	}

	if (pktap_v2_hdr->pth_ipproto == IPPROTO_TCP) {
		found = inp_findinpcb_procinfo(&tcbinfo,
		    pktap_v2_hdr->pth_flowid, &soprocinfo);
	} else if (pktap_v2_hdr->pth_ipproto == IPPROTO_UDP) {
		found = inp_findinpcb_procinfo(&udbinfo,
		    pktap_v2_hdr->pth_flowid, &soprocinfo);
	} else {
		found = inp_findinpcb_procinfo(&ripcbinfo,
		    pktap_v2_hdr->pth_flowid, &soprocinfo);
	}
	if (found == 1) {
		pktap_v2_set_procinfo(pktap_v2_hdr, &soprocinfo);
	}
}

__private_extern__ void
pktap_fill_proc_info(struct pktap_header *hdr, protocol_family_t proto,
    struct mbuf *m, u_int32_t pre, int outgoing, struct ifnet *ifp)
{
	/*
	 * Getting the pid and procname is expensive
	 * For outgoing, do the lookup only if there's an
	 * associated socket as indicated by the flowhash
	 */
	if (outgoing != 0 && m->m_pkthdr.pkt_flowsrc == FLOWSRC_INPCB) {
		/*
		 * To avoid lock ordering issues we delay the proc UUID lookup
		 * to the BPF read as we cannot
		 * assume the socket lock is unlocked on output
		 */
		hdr->pth_flags |= PTH_FLAG_DELAY_PKTAP;
		hdr->pth_flags |= PTH_FLAG_SOCKET;
		hdr->pth_flowid = m->m_pkthdr.pkt_flowid;

		if (m->m_pkthdr.pkt_flags & PKTF_FLOW_RAWSOCK) {
			hdr->pth_ipproto = IPPROTO_RAW;
		} else {
			hdr->pth_ipproto = m->m_pkthdr.pkt_proto;
		}

		if (hdr->pth_ipproto == IPPROTO_TCP) {
			hdr->pth_pid = m->m_pkthdr.tx_tcp_pid;
			hdr->pth_epid = m->m_pkthdr.tx_tcp_e_pid;
		} else if (hdr->pth_ipproto == IPPROTO_UDP) {
			hdr->pth_pid = m->m_pkthdr.tx_udp_pid;
			hdr->pth_epid = m->m_pkthdr.tx_udp_e_pid;
		} else if (hdr->pth_ipproto == IPPROTO_RAW) {
			hdr->pth_pid = m->m_pkthdr.tx_rawip_pid;
			hdr->pth_epid = m->m_pkthdr.tx_rawip_e_pid;
		}

		if (hdr->pth_pid != 0 && hdr->pth_pid != -1) {
			proc_name(hdr->pth_pid, hdr->pth_comm, MAXCOMLEN);
		} else {
			hdr->pth_pid = -1;
		}

		if (hdr->pth_epid != 0 && hdr->pth_epid != -1) {
			hdr->pth_flags |= PTH_FLAG_PROC_DELEGATED;
			proc_name(hdr->pth_epid, hdr->pth_ecomm, MAXCOMLEN);
		} else {
			hdr->pth_epid = -1;
		}

		if (m->m_pkthdr.pkt_flags & PKTF_NEW_FLOW) {
			hdr->pth_flags |= PTH_FLAG_NEW_FLOW;
		}
	} else if (outgoing == 0) {
		int found = 0;
		struct so_procinfo soprocinfo;
		struct inpcb *inp = NULL;

		memset(&soprocinfo, 0, sizeof(struct so_procinfo));

		if (proto == PF_INET) {
			struct ip ip;
			errno_t error;
			size_t hlen;
			struct in_addr faddr, laddr;
			u_short fport = 0, lport = 0;
			struct inpcbinfo *pcbinfo = NULL;
			int wildcard = 0;

			error = mbuf_copydata(m, pre, sizeof(struct ip), &ip);
			if (error != 0) {
				PKTAP_LOG(PKTP_LOG_ERROR,
				    "mbuf_copydata tcp v4 failed for %s\n",
				    hdr->pth_ifname);
				goto done;
			}
			hlen = IP_VHL_HL(ip.ip_vhl) << 2;

			faddr = ip.ip_src;
			laddr = ip.ip_dst;

			if (ip.ip_p == IPPROTO_TCP) {
				struct tcphdr th;

				error = mbuf_copydata(m, pre + hlen,
				    sizeof(struct tcphdr), &th);
				if (error != 0) {
					goto done;
				}

				fport = th.th_sport;
				lport = th.th_dport;

				pcbinfo = &tcbinfo;
			} else if (ip.ip_p == IPPROTO_UDP) {
				struct udphdr uh;

				error = mbuf_copydata(m, pre + hlen,
				    sizeof(struct udphdr), &uh);
				if (error != 0) {
					PKTAP_LOG(PKTP_LOG_ERROR,
					    "mbuf_copydata udp v4 failed for %s\n",
					    hdr->pth_ifname);
					goto done;
				}
				fport = uh.uh_sport;
				lport = uh.uh_dport;

				pcbinfo = &udbinfo;
				wildcard = 1;
			}
			if (pcbinfo != NULL) {
				inp = in_pcblookup_hash_try(pcbinfo, faddr,
				    fport, laddr, lport, wildcard,
				    outgoing ? NULL : ifp);

				if (inp == NULL && hdr->pth_iftype != IFT_LOOP) {
					PKTAP_LOG(PKTP_LOG_NOPCB,
					    "in_pcblookup_hash_try no pcb %s\n",
					    hdr->pth_ifname);
				}
			} else {
				PKTAP_LOG(PKTP_LOG_NOPCB,
				    "unknown ip_p %u on %s\n",
				    ip.ip_p, hdr->pth_ifname);
				pktap_hexdump(PKTP_LOG_NOPCB, &ip, sizeof(struct ip));
			}
		} else if (proto == PF_INET6) {
			struct ip6_hdr ip6;
			errno_t error;
			struct in6_addr *faddr;
			struct in6_addr *laddr;
			u_short fport = 0, lport = 0;
			struct inpcbinfo *pcbinfo = NULL;
			int wildcard = 0;

			error = mbuf_copydata(m, pre, sizeof(struct ip6_hdr), &ip6);
			if (error != 0) {
				goto done;
			}

			faddr = &ip6.ip6_src;
			laddr = &ip6.ip6_dst;

			if (ip6.ip6_nxt == IPPROTO_TCP) {
				struct tcphdr th;

				error = mbuf_copydata(m, pre + sizeof(struct ip6_hdr),
				    sizeof(struct tcphdr), &th);
				if (error != 0) {
					PKTAP_LOG(PKTP_LOG_ERROR,
					    "mbuf_copydata tcp v6 failed for %s\n",
					    hdr->pth_ifname);
					goto done;
				}

				fport = th.th_sport;
				lport = th.th_dport;

				pcbinfo = &tcbinfo;
			} else if (ip6.ip6_nxt == IPPROTO_UDP) {
				struct udphdr uh;

				error = mbuf_copydata(m, pre + sizeof(struct ip6_hdr),
				    sizeof(struct udphdr), &uh);
				if (error != 0) {
					PKTAP_LOG(PKTP_LOG_ERROR,
					    "mbuf_copydata udp v6 failed for %s\n",
					    hdr->pth_ifname);
					goto done;
				}

				fport = uh.uh_sport;
				lport = uh.uh_dport;

				pcbinfo = &udbinfo;
				wildcard = 1;
			}
			if (pcbinfo != NULL) {
				inp = in6_pcblookup_hash_try(pcbinfo, faddr, fport, ip6_input_getdstifscope(m),
				    laddr, lport, ip6_input_getsrcifscope(m), wildcard, outgoing ? NULL : ifp);

				if (inp == NULL && hdr->pth_iftype != IFT_LOOP) {
					PKTAP_LOG(PKTP_LOG_NOPCB,
					    "in6_pcblookup_hash_try no pcb %s\n",
					    hdr->pth_ifname);
				}
			} else {
				PKTAP_LOG(PKTP_LOG_NOPCB,
				    "unknown ip6.ip6_nxt %u on %s\n",
				    ip6.ip6_nxt, hdr->pth_ifname);
				pktap_hexdump(PKTP_LOG_NOPCB, &ip6, sizeof(struct ip6_hdr));
			}
		}
		if (inp != NULL) {
			hdr->pth_flags |= PTH_FLAG_SOCKET;
			if (inp->inp_state != INPCB_STATE_DEAD && inp->inp_socket != NULL) {
				found = 1;
				inp_get_soprocinfo(inp, &soprocinfo);
			}
			in_pcb_checkstate(inp, WNT_RELEASE, 0);
		}
done:
		/*
		 * -1 means PID not found
		 */
		hdr->pth_pid = -1;
		hdr->pth_epid = -1;

		if (found != 0) {
			pktap_set_procinfo(hdr, &soprocinfo);
		}
	}
}

__private_extern__ void
pktap_bpf_tap(struct ifnet *ifp, protocol_family_t proto, struct mbuf *m,
    u_int32_t pre, u_int32_t post, int outgoing)
{
	struct pktap_softc *__single pktap;
	void (*bpf_tap_func)(ifnet_t, u_int32_t, mbuf_t, void *, size_t) =
	    outgoing ? bpf_tap_out : bpf_tap_in;

	/*
	 * Skip the coprocessor interface
	 */
	if (!intcoproc_unrestricted && IFNET_IS_INTCOPROC(ifp)) {
		return;
	}

	lck_rw_lock_shared(&pktap_lck_rw);

	/*
	 * No need to take the ifnet_lock as the struct ifnet field if_bpf is
	 * protected by the BPF subsystem
	 */
	LIST_FOREACH(pktap, &pktap_list, pktp_link) {
		int filter_result;

		filter_result = pktap_filter_evaluate(pktap, ifp);
		if (filter_result == PKTAP_FILTER_SKIP) {
			continue;
		}

		if (pktap->pktp_dlt_raw_count > 0) {
			/* We accept only IPv4 and IPv6 packets for the raw DLT */
			if ((proto == AF_INET || proto == AF_INET6) &&
			    !(m->m_pkthdr.pkt_flags & PKTF_INET_RESOLVE)) {
				/*
				 * We can play just with the length of the first mbuf in the
				 * chain because bpf_tap_imp() disregard the packet length
				 * of the mbuf packet header.
				 */
				if (mbuf_setdata(m, m_mtod_current(m) + pre, m->m_len - pre) == 0) {
					bpf_tap_func(pktap->pktp_ifp, DLT_RAW, m, NULL, 0);
					mbuf_setdata(m, m_mtod_current(m) - pre, m->m_len + pre);
				}
			}
		}

		if (pktap->pktp_dlt_pkttap_count > 0) {
			struct {
				struct pktap_header hdr;
				u_int32_t proto;
			} hdr_buffer;
			struct pktap_header *hdr = &hdr_buffer.hdr;
			size_t hdr_size = sizeof(struct pktap_header);
			int unknown_if_type = 0;
			size_t data_adjust = 0;
			u_int32_t pre_adjust = 0;

			/* Verify the structure is packed */
			static_assert(sizeof(hdr_buffer) == sizeof(struct pktap_header) + sizeof(u_int32_t));

			bzero(&hdr_buffer, sizeof(hdr_buffer));
			hdr->pth_length = sizeof(struct pktap_header);
			hdr->pth_type_next = PTH_TYPE_PACKET;

			/*
			 * Set DLT of packet based on interface type
			 */
			switch (ifp->if_type) {
			case IFT_LOOP:
			case IFT_GIF:
			case IFT_STF:
			case IFT_CELLULAR:
				/*
				 * Packets from pdp interfaces have no loopback
				 * header that contain the protocol number.
				 * As BPF just concatenate the header and the
				 * packet content in a single buffer,
				 * stash the protocol after the pktap header
				 * and adjust the size of the header accordingly
				 */
				hdr->pth_dlt = DLT_NULL;
				if (pre == 0) {
					hdr_buffer.proto = proto;
					hdr_size = sizeof(hdr_buffer);
					pre_adjust = sizeof(hdr_buffer.proto);
				}
				break;
			case IFT_ETHER:
			case IFT_BRIDGE:
			case IFT_L2VLAN:
			case IFT_IEEE8023ADLAG:
				hdr->pth_dlt = DLT_EN10MB;
				break;
			case IFT_PPP:
				hdr->pth_dlt = DLT_PPP;
				break;
			case IFT_IEEE1394:
				hdr->pth_dlt = DLT_APPLE_IP_OVER_IEEE1394;
				break;
			case IFT_OTHER:
				if (ifp->if_family == IFNET_FAMILY_IPSEC ||
				    ifp->if_family == IFNET_FAMILY_UTUN) {
					/*
					 * For utun:
					 * - incoming packets do not have the prefix set to four
					 * - some packets are as small as two bytes!
					 */
					if (m_pktlen(m) < 4) {
						goto done;
					}
					if (proto != AF_INET && proto != AF_INET6) {
						goto done;
					}
					if (proto == AF_INET && (size_t) m_pktlen(m) - 4 < sizeof(struct ip)) {
						goto done;
					}
					if (proto == AF_INET6 && (size_t) m_pktlen(m) - 4 < sizeof(struct ip6_hdr)) {
						goto done;
					}

					/*
					 * Handle two cases:
					 * - The old utun encapsulation with the protocol family in network order
					 * - A raw IPv4 or IPv6 packet
					 */
					uint8_t data = *mtod(m, uint8_t *);
					if ((data >> 4) == 4 || (data >> 4) == 6) {
						pre = 4;
					} else {
						/*
						 * Skip the protocol in the mbuf as it's in network order
						 */
						pre = 4;
						data_adjust = 4;
					}
				}
				hdr->pth_dlt = DLT_NULL;
				hdr_buffer.proto = proto;
				hdr_size = sizeof(hdr_buffer);
				break;
			default:
				if (pre == 0) {
					hdr->pth_dlt = DLT_RAW;
				} else {
					unknown_if_type = 1;
				}
				break;
			}
			if (unknown_if_type) {
				PKTAP_LOG(PKTP_LOG_FUNC,
				    "unknown if_type %u for %s\n",
				    ifp->if_type, ifp->if_xname);
				pktap_count_unknown_if_type += 1;
			} else {
				strlcpy(hdr->pth_ifname, ifp->if_xname,
				    sizeof(hdr->pth_ifname));
				hdr->pth_flags |= outgoing ? PTH_FLAG_DIR_OUT : PTH_FLAG_DIR_IN;
				hdr->pth_protocol_family = proto;
				hdr->pth_frame_pre_length = pre + pre_adjust;
				hdr->pth_frame_post_length = post;
				hdr->pth_iftype = ifp->if_type;
				hdr->pth_ifunit = ifp->if_unit;

				if (m->m_pkthdr.pkt_flags & PKTF_KEEPALIVE) {
					hdr->pth_flags |= PTH_FLAG_KEEP_ALIVE;
				}
				if (m->m_pkthdr.pkt_flags & PKTF_TCP_REXMT) {
					hdr->pth_flags |= PTH_FLAG_REXMIT;
				}
				if (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT) {
					hdr->pth_flags |= PTH_FLAG_WAKE_PKT;
				}

				/* Need to check the packet flag in case full wake has been requested */
				if (m->m_pkthdr.pkt_ext_flags & PKTF_EXT_LPW || if_is_lpw_enabled(ifp)) {
					hdr->pth_flags |= PTH_FLAG_LPW;
				}
				if (outgoing != 0) {
					hdr->pth_comp_gencnt = m->m_pkthdr.comp_gencnt;
				}

				pktap_fill_proc_info(hdr, proto, m, pre, outgoing, ifp);

				hdr->pth_svc = so_svc2tc(m->m_pkthdr.pkt_svc);

				if (data_adjust == 0) {
					bpf_tap_func(pktap->pktp_ifp, DLT_PKTAP, m, &hdr_buffer,
					    hdr_size);
				} else {
					/*
					 * We can play just with the length of the first mbuf in the
					 * chain because bpf_tap_imp() disregard the packet length
					 * of the mbuf packet header.
					 */
					if (mbuf_setdata(m, m_mtod_current(m) + data_adjust, m->m_len - data_adjust) == 0) {
						bpf_tap_func(pktap->pktp_ifp, DLT_PKTAP, m, &hdr_buffer,
						    hdr_size);
						mbuf_setdata(m, m_mtod_current(m) - data_adjust, m->m_len + data_adjust);
					}
				}
			}
		}
	}
done:
	lck_rw_done(&pktap_lck_rw);
}

__private_extern__ void
pktap_input(struct ifnet *ifp, protocol_family_t proto, struct mbuf *m,
    char *frame_header)
{
	char *hdr;
	char *start;

	/* Fast path */
	if (pktap_total_tap_count == 0 ||
	    (m->m_pkthdr.pkt_flags & PKTF_SKIP_PKTAP) != 0) {
		return;
	}

	start = m_mtod_lower_bound(m);
	hdr = mtod(m, char *);
	/* Make sure the frame header is fully contained in the  mbuf */
	if (frame_header != NULL && frame_header >= start && frame_header <= hdr) {
		size_t o_len = m->m_len;
		u_int32_t pre = (u_int32_t)(hdr - frame_header);

		if (mbuf_setdata(m, frame_header, o_len + pre) == 0) {
			PKTAP_LOG(PKTP_LOG_INPUT, "ifp %s proto %u pre %u post %u\n",
			    ifp->if_xname, proto, pre, 0);

			pktap_bpf_tap(ifp, proto, m, pre, 0, 0);
			mbuf_setdata(m, hdr, o_len);
		}
	} else {
		PKTAP_LOG(PKTP_LOG_INPUT, "ifp %s proto %u pre %u post %u\n",
		    ifp->if_xname, proto, 0, 0);

		pktap_bpf_tap(ifp, proto, m, 0, 0, 0);
	}
}

__private_extern__ void
pktap_output(struct ifnet *ifp, protocol_family_t proto, struct mbuf *m,
    u_int32_t pre, u_int32_t post)
{
	/* Fast path */
	if (pktap_total_tap_count == 0 ||
	    (m->m_pkthdr.pkt_flags & PKTF_SKIP_PKTAP) != 0) {
		return;
	}

	PKTAP_LOG(PKTP_LOG_OUTPUT, "ifp %s proto %u pre %u post %u\n",
	    ifp->if_xname, proto, pre, post);

	pktap_bpf_tap(ifp, proto, m, pre, post, 1);
}

#if SKYWALK

typedef void (*tap_packet_func)(ifnet_t interface, u_int32_t dlt,
    kern_packet_t packet, void *__sized_by(header_len) header, size_t header_len);

static void
pktap_bpf_tap_packet(struct ifnet *ifp, protocol_family_t proto, uint32_t dlt,
    pid_t pid, const char * pname, pid_t epid, const char * epname,
    kern_packet_t pkt, const void *__sized_by(header_length) header, size_t header_length,
    uint8_t ipproto, uint32_t flowid, uint32_t flags, tap_packet_func tap_func)
{
	struct {
		struct pktap_header     pkth;
		union {
			uint8_t         llhdr[16];
			uint32_t        proto;
		} extra;
	} hdr_buffer;
	struct pktap_header     *hdr;
	size_t                  hdr_size;
	struct pktap_softc      *__single pktap;
	uint32_t                pre_length = 0;

	/*
	 * Skip the coprocessor interface
	 */
	if (!intcoproc_unrestricted && IFNET_IS_INTCOPROC(ifp)) {
		return;
	}

	if (proto != AF_INET && proto != AF_INET6) {
		PKTAP_LOG(PKTP_LOG_ERROR,
		    "unsupported protocol %d\n",
		    proto);
		return;
	}

	/* assume that we'll be tapping using PKTAP */
	hdr = &hdr_buffer.pkth;
	bzero(&hdr_buffer, sizeof(hdr_buffer));
	hdr->pth_length = sizeof(struct pktap_header);
	hdr->pth_type_next = PTH_TYPE_PACKET;
	hdr->pth_dlt = dlt;
	hdr->pth_pid = pid;
	if (pid != epid) {
		hdr->pth_epid = epid;
	} else {
		hdr->pth_epid = -1;
	}
	if (pname != NULL) {
		strlcpy(hdr->pth_comm, pname, sizeof(hdr->pth_comm));
	}
	if (epname != NULL) {
		strlcpy(hdr->pth_ecomm, epname, sizeof(hdr->pth_ecomm));
	}
	strlcpy(hdr->pth_ifname, ifp->if_xname, sizeof(hdr->pth_ifname));
	hdr->pth_flags |= flags;
	hdr->pth_ipproto = ipproto;
	hdr->pth_flowid = flowid;
	/*
	 * Do the same as pktap_fill_proc_info() to defer looking up inpcb.
	 * We do it for both inbound and outbound packets unlike the mbuf case.
	 */
	if ((flags & PTH_FLAG_SOCKET) != 0 && ipproto != 0 && flowid != 0) {
		hdr->pth_flags |= PTH_FLAG_DELAY_PKTAP;
	}
	if (kern_packet_get_wake_flag(pkt)) {
		hdr->pth_flags |= PTH_FLAG_WAKE_PKT;
	}

	/* Need to check the packet flag in case full wake has been requested */
	if (kern_packet_get_lpw_flag(pkt) || if_is_lpw_enabled(ifp)) {
		hdr->pth_flags |= PTH_FLAG_LPW;
	}
	kern_packet_get_compression_generation_count(pkt, &hdr->pth_comp_gencnt);

	hdr->pth_trace_tag = kern_packet_get_trace_tag(pkt);
	hdr->pth_protocol_family = proto;
	hdr->pth_svc = so_svc2tc((mbuf_svc_class_t)
	    kern_packet_get_service_class(pkt));
	hdr->pth_iftype = ifp->if_type;
	hdr->pth_ifunit = ifp->if_unit;
	hdr_size = sizeof(struct pktap_header);
	if (header != NULL && header_length != 0) {
		if (header_length > sizeof(hdr_buffer.extra.llhdr)) {
			PKTAP_LOG(PKTP_LOG_ERROR,
			    "%s: header %d > %d\n",
			    if_name(ifp), (int)header_length,
			    (int)sizeof(hdr_buffer.extra.llhdr));
			return;
		}
		bcopy(header, hdr_buffer.extra.llhdr, header_length);
		hdr_size += header_length;
		pre_length = (uint32_t)header_length;
	} else if (dlt == DLT_RAW) {
		/*
		 * Use the same DLT as has been used for the mbuf path
		 */
		hdr->pth_dlt = DLT_NULL;
		hdr_buffer.extra.proto = proto;
		hdr_size = sizeof(struct pktap_header) + sizeof(u_int32_t);
		pre_length = sizeof(hdr_buffer.extra.proto);
	} else if (dlt == DLT_EN10MB) {
		pre_length = ETHER_HDR_LEN;
	}
	hdr->pth_frame_pre_length = pre_length;

	lck_rw_lock_shared(&pktap_lck_rw);
	/*
	 * No need to take the ifnet_lock as the struct ifnet field if_bpf is
	 * protected by the BPF subsystem
	 */
	LIST_FOREACH(pktap, &pktap_list, pktp_link) {
		int filter_result;

		filter_result = pktap_filter_evaluate(pktap, ifp);
		if (filter_result == PKTAP_FILTER_SKIP) {
			continue;
		}

		if (dlt == DLT_RAW && pktap->pktp_dlt_raw_count > 0) {
			(*tap_func)(pktap->pktp_ifp, DLT_RAW, pkt, NULL, 0);
		}
		if (pktap->pktp_dlt_pkttap_count > 0) {
			(*tap_func)(pktap->pktp_ifp, DLT_PKTAP,
			    pkt, &hdr_buffer, hdr_size);
		}
	}
	lck_rw_done(&pktap_lck_rw);
}

void
pktap_input_packet(struct ifnet *ifp, protocol_family_t proto, uint32_t dlt,
    pid_t pid, const char * pname, pid_t epid, const char * epname,
    kern_packet_t pkt, const void *__sized_by(header_length) header, size_t header_length,
    uint8_t ipproto, uint32_t flowid, uint32_t flags)
{
	/* Fast path */
	if (pktap_total_tap_count == 0) {
		return;
	}

	PKTAP_LOG(PKTP_LOG_INPUT, "IN %s proto %u pid %d epid %d\n",
	    ifp->if_xname, proto, pid, epid);
	pktap_bpf_tap_packet(ifp, proto, dlt, pid, pname, epid, epname, pkt,
	    header, header_length, ipproto, flowid,
	    PTH_FLAG_DIR_IN | (flags & ~(PTH_FLAG_DIR_IN | PTH_FLAG_DIR_OUT)),
	    bpf_tap_packet_in);
}

void
pktap_output_packet(struct ifnet *ifp, protocol_family_t proto, uint32_t dlt,
    pid_t pid, const char * pname, pid_t epid, const char * epname,
    kern_packet_t pkt, const void *__sized_by(header_length) header, size_t header_length,
    uint8_t ipproto, uint32_t flowid, uint32_t flags)
{
	/* Fast path */
	if (pktap_total_tap_count == 0) {
		return;
	}

	PKTAP_LOG(PKTP_LOG_OUTPUT, "OUT %s proto %u pid %d epid %d\n",
	    ifp->if_xname, proto, pid, epid);
	pktap_bpf_tap_packet(ifp, proto, dlt, pid, pname, epid, epname, pkt,
	    header, header_length, ipproto, flowid,
	    PTH_FLAG_DIR_OUT | (flags & ~(PTH_FLAG_DIR_IN | PTH_FLAG_DIR_OUT)),
	    bpf_tap_packet_out);
}

#endif /* SKYWALK */

void
convert_to_pktap_header_to_v2(struct bpf_packet *bpf_pkt, bool truncate)
{
	struct pktap_header *pktap_header;
	size_t extra_src_size;
	struct pktap_buffer_v2_hdr_extra pktap_buffer_v2_hdr_extra;
	struct pktap_v2_hdr_space *pktap_v2_hdr_space;
	struct pktap_v2_hdr *pktap_v2_hdr;
	uint8_t *ptr;

	pktap_header = (struct pktap_header *)bpf_pkt->bpfp_header;

	if (pktap_header->pth_type_next != PTH_TYPE_PACKET) {
		return;
	}

	VERIFY(bpf_pkt->bpfp_header_length >= sizeof(struct pktap_header));

	/*
	 * extra_src_size is the length of the optional link layer header
	 */
	extra_src_size = bpf_pkt->bpfp_header_length -
	    sizeof(struct pktap_header);

	VERIFY(extra_src_size <= sizeof(union pktap_header_extra));

	pktap_v2_hdr_space = &pktap_buffer_v2_hdr_extra.hdr_space;
	pktap_v2_hdr = &pktap_v2_hdr_space->pth_hdr;
	ptr = (uint8_t*) &pktap_buffer_v2_hdr_extra + sizeof(*pktap_v2_hdr);

	COPY_PKTAP_COMMON_FIELDS_TO_V2(pktap_v2_hdr, pktap_header);

	/*
	 * When truncating don't bother with the process UUIDs
	 */
	if (!truncate) {
		if ((pktap_header->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
			pktap_v2_hdr->pth_uuid_offset = pktap_v2_hdr->pth_length;
			pktap_v2_hdr->pth_length += sizeof(uuid_t);
			uuid_clear(*(uuid_t *)ptr);
			ptr += sizeof(uuid_t);
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		} else if (!uuid_is_null(pktap_header->pth_uuid)) {
			pktap_v2_hdr->pth_uuid_offset = pktap_v2_hdr->pth_length;
			uuid_copy(*(uuid_t *)ptr, pktap_header->pth_uuid);
			pktap_v2_hdr->pth_length += sizeof(uuid_t);
			ptr += sizeof(uuid_t);
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		}

		if ((pktap_header->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
			if (pktap_header->pth_flags & PTH_FLAG_PROC_DELEGATED) {
				pktap_v2_hdr->pth_e_uuid_offset = pktap_v2_hdr->pth_length;
				uuid_clear(*(uuid_t *)ptr);
				pktap_v2_hdr->pth_length += sizeof(uuid_t);
				ptr += sizeof(uuid_t);
				VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
			}
		} else if (!uuid_is_null(pktap_header->pth_euuid)) {
			pktap_v2_hdr->pth_e_uuid_offset = pktap_v2_hdr->pth_length;
			uuid_copy(*(uuid_t *)ptr, pktap_header->pth_euuid);
			pktap_v2_hdr->pth_length += sizeof(uuid_t);
			ptr += sizeof(uuid_t);
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		}
	}

	if (pktap_header->pth_ifname[0] != 0) {
		size_t strsize;

		pktap_v2_hdr->pth_ifname_offset = pktap_v2_hdr->pth_length;

		/*
		 * Note: strlcpy() returns the length of the string so we need
		 * to add one for the end-of-string
		 */
		size_t remaining_space = (uintptr_t)(pktap_v2_hdr_space + 1) - (uintptr_t)ptr;
		strsize = 1 + strlen(strbufcpy((char *)ptr,
		    remaining_space,
		    pktap_header->pth_ifname,
		    sizeof(pktap_v2_hdr_space->pth_ifname)));
		pktap_v2_hdr->pth_length += strsize;
		ptr += strsize;
		VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
	}

	/*
	 * Do not waste space with the process name if we do not have a pid
	 */
	if (pktap_header->pth_pid != 0 && pktap_header->pth_pid != -1) {
		if (pktap_header->pth_comm[0] != 0) {
			size_t strsize;

			pktap_v2_hdr->pth_comm_offset = pktap_v2_hdr->pth_length;

			size_t remaining_space = (uintptr_t)(pktap_v2_hdr_space + 1) - (uintptr_t)ptr;
			strsize = 1 +  strlen(strbufcpy((char *)ptr, remaining_space,
			    pktap_header->pth_comm,
			    sizeof(pktap_v2_hdr_space->pth_comm)));
			pktap_v2_hdr->pth_length += strsize;
			ptr += strsize;
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		} else if ((pktap_header->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
			size_t strsize = sizeof(pktap_v2_hdr_space->pth_comm);

			pktap_v2_hdr->pth_comm_offset = pktap_v2_hdr->pth_length;

			*ptr = 0;       /* empty string by default */
			pktap_v2_hdr->pth_length += strsize;
			ptr += strsize;
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		}
	}

	/*
	 * Do not waste space with the effective process name if we do not have
	 * an effective pid or it's the same as the pid
	 */
	if (pktap_header->pth_epid != 0 && pktap_header->pth_epid != -1 &&
	    pktap_header->pth_epid != pktap_header->pth_pid) {
		if (pktap_header->pth_ecomm[0] != 0) {
			size_t strsize;

			pktap_v2_hdr->pth_e_comm_offset = pktap_v2_hdr->pth_length;

			size_t remaining_space = (uintptr_t)(pktap_v2_hdr_space + 1) - (uintptr_t)ptr;

			strsize = 1 + strlen(strbufcpy((char *)ptr,
			    remaining_space,
			    pktap_header->pth_ecomm,
			    sizeof(pktap_v2_hdr_space->pth_e_comm)));
			pktap_v2_hdr->pth_length += strsize;
			ptr += strsize;
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		} else if ((pktap_header->pth_flags & PTH_FLAG_DELAY_PKTAP)) {
			size_t strsize = sizeof(pktap_v2_hdr_space->pth_e_comm);

			pktap_v2_hdr->pth_e_comm_offset = pktap_v2_hdr->pth_length;
			*ptr = 0;       /* empty string by default */
			pktap_v2_hdr->pth_length += strsize;
			ptr += strsize;
			VERIFY((void *)ptr < (void *)(pktap_v2_hdr_space + 1));
		}
	}

	if (extra_src_size > 0) {
		uint8_t *extra_src_ptr = (uint8_t *)bpf_pkt->bpfp_header + sizeof(*pktap_header);
		uint8_t *extra_dst_ptr = (uint8_t *)&pktap_buffer_v2_hdr_extra + pktap_v2_hdr->pth_length;

		VERIFY(pktap_v2_hdr->pth_length + extra_src_size <=
		    sizeof(struct pktap_buffer_v2_hdr_extra));

		memcpy(extra_dst_ptr, extra_src_ptr, extra_src_size);
	}

	VERIFY(pktap_v2_hdr->pth_length + extra_src_size <=
	    bpf_pkt->bpfp_header_length);

	memcpy(bpf_pkt->bpfp_header, &pktap_buffer_v2_hdr_extra,
	    pktap_v2_hdr->pth_length + extra_src_size);
	/*
	 * For -fbounds-safety, we override the length which
	 * is fragile.  However, this is only called from
	 * BPF which passes us a buffer allocated on the stack
	 * and, in practice, that isn't going to cause any problems.
	 */
	bpf_pkt->bpfp_header = bpf_pkt->bpfp_header;
	bpf_pkt->bpfp_header_length += pktap_v2_hdr->pth_length -
	    sizeof(struct pktap_header);

	bpf_pkt->bpfp_total_length += pktap_v2_hdr->pth_length -
	    sizeof(struct pktap_header);
}
