xnu-2422.110.17.tar.gz

[apple/xnu.git] / bsd / kern / kpi_mbuf.c

/*
 * Copyright (c) 2004-2012 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@
 */

#define __KPI__
//#include <sys/kpi_interface.h>

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/mcache.h>
#include <sys/socket.h>
#include <kern/debug.h>
#include <libkern/OSAtomic.h>
#include <kern/kalloc.h>
#include <string.h>
#include <netinet/in.h>
#include <netinet/ip_var.h>

#include "net/net_str_id.h"

/* mbuf flags visible to KPI clients; do not add private flags here */
static const mbuf_flags_t mbuf_flags_mask = (MBUF_EXT | MBUF_PKTHDR | MBUF_EOR |
    MBUF_LOOP | MBUF_BCAST | MBUF_MCAST | MBUF_FRAG | MBUF_FIRSTFRAG |
    MBUF_LASTFRAG | MBUF_PROMISC | MBUF_HASFCS);

/* Unalterable mbuf flags */
static const mbuf_flags_t mbuf_cflags_mask = (MBUF_EXT);

void* mbuf_data(mbuf_t mbuf)
{
        return mbuf->m_data;
}

void* mbuf_datastart(mbuf_t mbuf)
{
        if (mbuf->m_flags & M_EXT)
                return mbuf->m_ext.ext_buf;
        if (mbuf->m_flags & M_PKTHDR)
                return mbuf->m_pktdat;
        return mbuf->m_dat;
}

errno_t mbuf_setdata(mbuf_t mbuf, void* data, size_t len)
{
        size_t  start = (size_t)((char*)mbuf_datastart(mbuf));
        size_t  maxlen = mbuf_maxlen(mbuf);
        
        if ((size_t)data < start || ((size_t)data) + len > start + maxlen)
                return EINVAL;
        mbuf->m_data = data;
        mbuf->m_len = len;
        
        return 0;
}

errno_t mbuf_align_32(mbuf_t mbuf, size_t len)
{
        if ((mbuf->m_flags & M_EXT) != 0 && m_mclhasreference(mbuf))
                return ENOTSUP;
        mbuf->m_data = mbuf_datastart(mbuf);
        mbuf->m_data += ((mbuf_trailingspace(mbuf) - len) &~ (sizeof(u_int32_t) - 1));
        
        return 0;
}

/* This function is used to provide mcl_to_paddr via symbol indirection,
 * please avoid any change in behavior or remove the indirection in 
 * config/Unsupported*
 */
addr64_t mbuf_data_to_physical(void* ptr)
{
        return ((addr64_t)mcl_to_paddr(ptr));
}

errno_t mbuf_get(mbuf_how_t how, mbuf_type_t type, mbuf_t *mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        *mbuf = m_get(how, type);
        
        return (*mbuf == NULL) ? ENOMEM : 0;
}

errno_t mbuf_gethdr(mbuf_how_t how, mbuf_type_t type, mbuf_t *mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        *mbuf = m_gethdr(how, type);
        
        return (*mbuf == NULL) ? ENOMEM : 0;
}

errno_t
mbuf_attachcluster(mbuf_how_t how, mbuf_type_t type, mbuf_t *mbuf,
    caddr_t extbuf, void (*extfree)(caddr_t , u_int, caddr_t),
    size_t extsize, caddr_t extarg)
{
        if (mbuf == NULL || extbuf == NULL || extfree == NULL || extsize == 0)
                return (EINVAL);

        if ((*mbuf = m_clattach(*mbuf, type, extbuf,
            extfree, extsize, extarg, how)) == NULL)
                return (ENOMEM);

        return (0);
}

errno_t
mbuf_alloccluster(mbuf_how_t how, size_t *size, caddr_t *addr)
{
        if (size == NULL || *size == 0 || addr == NULL)
                return (EINVAL);

        *addr = NULL;

        /* Jumbo cluster pool not available? */
        if (*size > MBIGCLBYTES && njcl == 0)
                return (ENOTSUP);

        if (*size <= MCLBYTES && (*addr = m_mclalloc(how)) != NULL)
                *size = MCLBYTES;
        else if (*size > MCLBYTES && *size <= MBIGCLBYTES &&
            (*addr = m_bigalloc(how)) != NULL)
                *size = MBIGCLBYTES;
        else if (*size > MBIGCLBYTES && *size <= M16KCLBYTES &&
            (*addr = m_16kalloc(how)) != NULL)
                *size = M16KCLBYTES;
        else
                *size = 0;

        if (*addr == NULL)
                return (ENOMEM);

        return (0);
}

void
mbuf_freecluster(caddr_t addr, size_t size)
{
        if (size != MCLBYTES && size != MBIGCLBYTES && size != M16KCLBYTES)
                panic("%s: invalid size (%ld) for cluster %p", __func__,
                    size, (void *)addr);

        if (size == MCLBYTES)
                m_mclfree(addr);
        else if (size == MBIGCLBYTES)
                m_bigfree(addr, MBIGCLBYTES, NULL);
        else if (njcl > 0)
                m_16kfree(addr, M16KCLBYTES, NULL);
        else
                panic("%s: freeing jumbo cluster to an empty pool", __func__);
}

errno_t
mbuf_getcluster(mbuf_how_t how, mbuf_type_t type, size_t size, mbuf_t* mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        errno_t error = 0;
        int     created = 0;

        if (mbuf == NULL)
                return EINVAL;
        if (*mbuf == NULL) {
                *mbuf = m_get(how, type);
                if (*mbuf == NULL)
                        return ENOMEM;
                created = 1;
        }
        /*
         * At the time this code was written, m_{mclget,mbigget,m16kget}
         * would always return the same value that was passed in to it.
         */
        if (size == MCLBYTES) {
                *mbuf = m_mclget(*mbuf, how);
        } else if (size == MBIGCLBYTES) {
                *mbuf = m_mbigget(*mbuf, how);
        } else if (size == M16KCLBYTES) {
                if (njcl > 0) {
                        *mbuf = m_m16kget(*mbuf, how);
                } else {
                        /* Jumbo cluster pool not available? */
                        error = ENOTSUP;
                        goto out;
                }
        } else {
                error = EINVAL;
                goto out;
        }
        if (*mbuf == NULL || ((*mbuf)->m_flags & M_EXT) == 0)
                error = ENOMEM;
out:
        if (created && error != 0) {
                mbuf_free(*mbuf);
                *mbuf = NULL;
        }
        return error;   
}

errno_t mbuf_mclget(mbuf_how_t how, mbuf_type_t type, mbuf_t *mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        errno_t error = 0;
        int             created = 0;
        if (mbuf == NULL) return EINVAL;
        if (*mbuf == NULL) {
                error = mbuf_get(how, type, mbuf);
                if (error)
                        return error;
                created = 1;
        }
        
        /*
         * At the time this code was written, m_mclget would always
         * return the same value that was passed in to it.
         */
        *mbuf = m_mclget(*mbuf, how);
        
        if (created && ((*mbuf)->m_flags & M_EXT) == 0) {
                mbuf_free(*mbuf);
                *mbuf = NULL;
        }
        if (*mbuf == NULL || ((*mbuf)->m_flags & M_EXT) == 0)
                error = ENOMEM;
        return error;   
}


errno_t mbuf_getpacket(mbuf_how_t how, mbuf_t *mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        errno_t error = 0;
        
        *mbuf = m_getpacket_how(how);
        
        if (*mbuf == NULL) {
                if (how == MBUF_WAITOK)
                        error = ENOMEM;
                else
                        error = EWOULDBLOCK;
        }
        
        return error;
}

/* This function is used to provide m_free via symbol indirection, please avoid
 * any change in behavior or remove the indirection in config/Unsupported*
 */
mbuf_t mbuf_free(mbuf_t mbuf)
{
        return m_free(mbuf);
}

/* This function is used to provide m_freem via symbol indirection, please avoid
 * any change in behavior or remove the indirection in config/Unsupported*
 */
void mbuf_freem(mbuf_t mbuf)
{
        m_freem(mbuf);
}

int     mbuf_freem_list(mbuf_t mbuf)
{
        return m_freem_list(mbuf);
}

size_t mbuf_leadingspace(const mbuf_t mbuf)
{
        return m_leadingspace(mbuf);
}

/* This function is used to provide m_trailingspace via symbol indirection,
 * please avoid any change in behavior or remove the indirection in 
 * config/Unsupported*
 */
size_t mbuf_trailingspace(const mbuf_t mbuf)
{
        return m_trailingspace(mbuf);
}

/* Manipulation */
errno_t mbuf_copym(const mbuf_t src, size_t offset, size_t len,
                                   mbuf_how_t how, mbuf_t *new_mbuf)
{
        /* Must set *mbuf to NULL in failure case */
        *new_mbuf = m_copym(src, offset, len, how);
        
        return (*new_mbuf == NULL) ? ENOMEM : 0;
}

errno_t mbuf_dup(const mbuf_t src, mbuf_how_t how, mbuf_t *new_mbuf)
{
        /* Must set *new_mbuf to NULL in failure case */
        *new_mbuf = m_dup(src, how);
        
        return (*new_mbuf == NULL) ? ENOMEM : 0;
}

errno_t mbuf_prepend(mbuf_t *orig, size_t len, mbuf_how_t how)
{
        /* Must set *orig to NULL in failure case */
        *orig = m_prepend_2(*orig, len, how);
        
        return (*orig == NULL) ? ENOMEM : 0;
}

errno_t mbuf_split(mbuf_t src, size_t offset,
                                        mbuf_how_t how, mbuf_t *new_mbuf)
{
        /* Must set *new_mbuf to NULL in failure case */
        *new_mbuf = m_split(src, offset, how);
        
        return (*new_mbuf == NULL) ? ENOMEM : 0;
}

errno_t mbuf_pullup(mbuf_t *mbuf, size_t len)
{
        /* Must set *mbuf to NULL in failure case */
        *mbuf = m_pullup(*mbuf, len);
        
        return (*mbuf == NULL) ? ENOMEM : 0;
}

errno_t mbuf_pulldown(mbuf_t src, size_t *offset, size_t len, mbuf_t *location)
{
        /* Must set *location to NULL in failure case */
        int new_offset;
        *location = m_pulldown(src, *offset, len, &new_offset);
        *offset = new_offset;
        
        return (*location == NULL) ? ENOMEM : 0;
}

/* This function is used to provide m_adj via symbol indirection, please avoid
 * any change in behavior or remove the indirection in config/Unsupported*
 */
void mbuf_adj(mbuf_t mbuf, int len)
{
        m_adj(mbuf, len);
}

errno_t mbuf_adjustlen(mbuf_t m, int amount)
{
        /* Verify m_len will be valid after adding amount */
        if (amount > 0) {
                int             used = (size_t)mbuf_data(m) - (size_t)mbuf_datastart(m) +
                                           m->m_len;
                
                if ((size_t)(amount + used) > mbuf_maxlen(m))
                        return EINVAL;
        }
        else if (-amount > m->m_len) {
                return EINVAL;
        }
        
        m->m_len += amount;
        return 0;
}

mbuf_t
mbuf_concatenate(mbuf_t dst, mbuf_t src)
{
        if (dst == NULL)
                return (NULL);

        m_cat(dst, src);

        /* return dst as is in the current implementation */
        return (dst);
}
errno_t mbuf_copydata(const mbuf_t m0, size_t off, size_t len, void* out_data)
{
        /* Copied m_copydata, added error handling (don't just panic) */
        int count;
        mbuf_t  m = m0;

        while (off > 0) {
                if (m == 0)
                        return EINVAL;
                if (off < (size_t)m->m_len)
                        break;
                off -= m->m_len;
                m = m->m_next;
        }
        while (len > 0) {
                if (m == 0)
                        return EINVAL;
                count = m->m_len - off > len ? len : m->m_len - off;
                bcopy(mtod(m, caddr_t) + off, out_data, count);
                len -= count;
                out_data = ((char*)out_data) + count;
                off = 0;
                m = m->m_next;
        }
        
        return 0;
}

int mbuf_mclhasreference(mbuf_t mbuf)
{
        if ((mbuf->m_flags & M_EXT))
                return m_mclhasreference(mbuf);
        else
                return 0;
}


/* mbuf header */
mbuf_t mbuf_next(const mbuf_t mbuf)
{
        return mbuf->m_next;
}

errno_t mbuf_setnext(mbuf_t mbuf, mbuf_t next)
{
        if (next && ((next)->m_nextpkt != NULL ||
                (next)->m_type == MT_FREE)) return EINVAL;
        mbuf->m_next = next;
        
        return 0;
}

mbuf_t mbuf_nextpkt(const mbuf_t mbuf)
{
        return mbuf->m_nextpkt;
}

void mbuf_setnextpkt(mbuf_t mbuf, mbuf_t nextpkt)
{
        mbuf->m_nextpkt = nextpkt;
}

size_t mbuf_len(const mbuf_t mbuf)
{
        return mbuf->m_len;
}

void mbuf_setlen(mbuf_t mbuf, size_t len)
{
        mbuf->m_len = len;
}

size_t mbuf_maxlen(const mbuf_t mbuf)
{
        if (mbuf->m_flags & M_EXT)
                return mbuf->m_ext.ext_size;
        return &mbuf->m_dat[MLEN] - ((char*)mbuf_datastart(mbuf));
}

mbuf_type_t mbuf_type(const mbuf_t mbuf)
{
        return mbuf->m_type;
}

errno_t mbuf_settype(mbuf_t mbuf, mbuf_type_t new_type)
{
        if (new_type == MBUF_TYPE_FREE) return EINVAL;
        
        m_mchtype(mbuf, new_type);
        
        return 0;
}

mbuf_flags_t
mbuf_flags(const mbuf_t mbuf)
{
        return (mbuf->m_flags & mbuf_flags_mask);
}

errno_t
mbuf_setflags(mbuf_t mbuf, mbuf_flags_t flags)
{
        errno_t ret = 0;

        if ((flags | (mbuf->m_flags & mbuf_flags_mask)) &
            (~mbuf_flags_mask | mbuf_cflags_mask)) {
                ret = EINVAL;
        } else {
                mbuf_flags_t oflags = mbuf->m_flags;
                mbuf->m_flags = flags | (mbuf->m_flags & ~mbuf_flags_mask);
                /*
                 * If M_PKTHDR bit has changed, we have work to do;
                 * m_reinit() will take care of setting/clearing the
                 * bit, as well as the rest of bookkeeping.
                 */
                if ((oflags ^ mbuf->m_flags) & M_PKTHDR) {
                        mbuf->m_flags ^= M_PKTHDR;      /* restore */
                        ret = m_reinit(mbuf,
                            (mbuf->m_flags & M_PKTHDR) ? 0 : 1);
                }
        }

        return (ret);
}

errno_t
mbuf_setflags_mask(mbuf_t mbuf, mbuf_flags_t flags, mbuf_flags_t mask)
{
        errno_t ret = 0;

        if ((flags | mask) & (~mbuf_flags_mask | mbuf_cflags_mask)) {
                ret = EINVAL;
        } else {
                mbuf_flags_t oflags = mbuf->m_flags;
                mbuf->m_flags = (flags & mask) | (mbuf->m_flags & ~mask);
                /*
                 * If M_PKTHDR bit has changed, we have work to do;
                 * m_reinit() will take care of setting/clearing the
                 * bit, as well as the rest of bookkeeping.
                 */
                if ((oflags ^ mbuf->m_flags) & M_PKTHDR) {
                        mbuf->m_flags ^= M_PKTHDR;      /* restore */
                        ret = m_reinit(mbuf,
                            (mbuf->m_flags & M_PKTHDR) ? 0 : 1);
                }
        }

        return (ret);
}

errno_t mbuf_copy_pkthdr(mbuf_t dest, const mbuf_t src)
{
        if (((src)->m_flags & M_PKTHDR) == 0)
                return EINVAL;
        
        m_copy_pkthdr(dest, src);
        
        return 0;
}

size_t mbuf_pkthdr_len(const mbuf_t mbuf)
{
        return mbuf->m_pkthdr.len;
}

void mbuf_pkthdr_setlen(mbuf_t mbuf, size_t len)
{
        mbuf->m_pkthdr.len = len;
}

void mbuf_pkthdr_adjustlen(mbuf_t mbuf, int amount)
{
        mbuf->m_pkthdr.len += amount;
}

ifnet_t mbuf_pkthdr_rcvif(const mbuf_t mbuf)
{
        // If we reference count ifnets, we should take a reference here before returning
        return mbuf->m_pkthdr.rcvif;
}

errno_t mbuf_pkthdr_setrcvif(mbuf_t mbuf, ifnet_t ifnet)
{
        /* May want to walk ifnet list to determine if interface is valid */
        mbuf->m_pkthdr.rcvif = (struct ifnet*)ifnet;
        return 0;
}

void* mbuf_pkthdr_header(const mbuf_t mbuf)
{
        return mbuf->m_pkthdr.pkt_hdr;
}

void mbuf_pkthdr_setheader(mbuf_t mbuf, void *header)
{
        mbuf->m_pkthdr.pkt_hdr = (void*)header;
}

void
mbuf_inbound_modified(mbuf_t mbuf)
{
        /* Invalidate hardware generated checksum flags */
        mbuf->m_pkthdr.csum_flags = 0;
}

void
mbuf_outbound_finalize(struct mbuf *m, u_int32_t pf, size_t o)
{
        /* Generate the packet in software, client needs it */
        switch (pf) {
        case PF_INET:
                (void) in_finalize_cksum(m, o, m->m_pkthdr.csum_flags);
                break;

        case PF_INET6:
#if INET6
                /*
                 * Checksum offload should not have been enabled when
                 * extension headers exist; indicate that the callee
                 * should skip such case by setting optlen to -1.
                 */
                (void) in6_finalize_cksum(m, o, -1, -1, m->m_pkthdr.csum_flags);
#endif /* INET6 */
                break;

        default:
                break;
        }
}

errno_t
mbuf_set_vlan_tag(
        mbuf_t mbuf,
        u_int16_t vlan)
{
        mbuf->m_pkthdr.csum_flags |= CSUM_VLAN_TAG_VALID;
        mbuf->m_pkthdr.vlan_tag = vlan;
        
        return 0;
}

errno_t
mbuf_get_vlan_tag(
        mbuf_t mbuf,
        u_int16_t *vlan)
{
        if ((mbuf->m_pkthdr.csum_flags & CSUM_VLAN_TAG_VALID) == 0)
                return ENXIO; // No vlan tag set
        
        *vlan = mbuf->m_pkthdr.vlan_tag;
        
        return 0;
}

errno_t
mbuf_clear_vlan_tag(
        mbuf_t mbuf)
{
        mbuf->m_pkthdr.csum_flags &= ~CSUM_VLAN_TAG_VALID;
        mbuf->m_pkthdr.vlan_tag = 0;
        
        return 0;
}

static const mbuf_csum_request_flags_t mbuf_valid_csum_request_flags = 
        MBUF_CSUM_REQ_IP | MBUF_CSUM_REQ_TCP | MBUF_CSUM_REQ_UDP |
        MBUF_CSUM_PARTIAL | MBUF_CSUM_REQ_TCPIPV6 | MBUF_CSUM_REQ_UDPIPV6;

errno_t
mbuf_set_csum_requested(
        mbuf_t mbuf,
        mbuf_csum_request_flags_t request,
        u_int32_t value)
{
        request &= mbuf_valid_csum_request_flags;
        mbuf->m_pkthdr.csum_flags = (mbuf->m_pkthdr.csum_flags & 0xffff0000) | request;
        mbuf->m_pkthdr.csum_data = value;
        
        return 0;
}

static const mbuf_tso_request_flags_t mbuf_valid_tso_request_flags = 
        MBUF_TSO_IPV4 | MBUF_TSO_IPV6;

errno_t
mbuf_get_tso_requested(
        mbuf_t mbuf,
        mbuf_tso_request_flags_t *request,
        u_int32_t *value)
{
        if (mbuf == NULL || (mbuf->m_flags & M_PKTHDR) == 0 ||
                        request == NULL || value == NULL)
                return EINVAL;

        *request = mbuf->m_pkthdr.csum_flags;
        *request &= mbuf_valid_tso_request_flags;
        if (*request && value != NULL) 
                *value = mbuf->m_pkthdr.tso_segsz;
        
        return 0;
}

errno_t
mbuf_get_csum_requested(
        mbuf_t mbuf,
        mbuf_csum_request_flags_t *request,
        u_int32_t *value)
{
        *request = mbuf->m_pkthdr.csum_flags;
        *request &= mbuf_valid_csum_request_flags;
        if (value != NULL) {
                *value = mbuf->m_pkthdr.csum_data;
        }
        
        return 0;
}

errno_t
mbuf_clear_csum_requested(
        mbuf_t mbuf)
{
        mbuf->m_pkthdr.csum_flags &= 0xffff0000;
        mbuf->m_pkthdr.csum_data = 0;
        
        return 0;
}

static const mbuf_csum_performed_flags_t mbuf_valid_csum_performed_flags = 
        MBUF_CSUM_DID_IP | MBUF_CSUM_IP_GOOD | MBUF_CSUM_DID_DATA |
        MBUF_CSUM_PSEUDO_HDR | MBUF_CSUM_PARTIAL;

errno_t
mbuf_set_csum_performed(
        mbuf_t mbuf,
        mbuf_csum_performed_flags_t performed,
        u_int32_t value)
{
        performed &= mbuf_valid_csum_performed_flags;
        mbuf->m_pkthdr.csum_flags = (mbuf->m_pkthdr.csum_flags & 0xffff0000) | performed;
        mbuf->m_pkthdr.csum_data = value;
        
        return 0;
}

errno_t
mbuf_get_csum_performed(
        mbuf_t mbuf,
        mbuf_csum_performed_flags_t *performed,
        u_int32_t *value)
{
        *performed = mbuf->m_pkthdr.csum_flags & mbuf_valid_csum_performed_flags;
        *value = mbuf->m_pkthdr.csum_data;
        
        return 0;
}

errno_t
mbuf_clear_csum_performed(
        mbuf_t mbuf)
{
        mbuf->m_pkthdr.csum_flags &= 0xffff0000;
        mbuf->m_pkthdr.csum_data = 0;
        
        return 0;
}

errno_t
mbuf_inet_cksum(mbuf_t mbuf, int protocol, u_int32_t offset, u_int32_t length,
    u_int16_t *csum)
{
        if (mbuf == NULL || length == 0 || csum == NULL ||
           (u_int32_t)mbuf->m_pkthdr.len < (offset + length))
                return (EINVAL);

        *csum = inet_cksum(mbuf, protocol, offset, length);
        return (0);
}

#if INET6
errno_t
mbuf_inet6_cksum(mbuf_t mbuf, int protocol, u_int32_t offset, u_int32_t length,
    u_int16_t *csum)
{
        if (mbuf == NULL || length == 0 || csum == NULL ||
           (u_int32_t)mbuf->m_pkthdr.len < (offset + length))
                return (EINVAL);

        *csum = inet6_cksum(mbuf, protocol, offset, length);
        return (0);
}
#else /* INET6 */
errno_t
mbuf_inet6_cksum(__unused mbuf_t mbuf, __unused int protocol,
                __unused u_int32_t offset, __unused u_int32_t length,
                __unused u_int16_t *csum)
{
        panic("mbuf_inet6_cksum() doesn't exist on this platform\n");
        return (0);
}

u_int16_t
inet6_cksum(__unused struct mbuf *m, __unused unsigned int nxt,
                __unused unsigned int off, __unused unsigned int len)
{
        panic("inet6_cksum() doesn't exist on this platform\n");
        return (0);
}

void nd6_lookup_ipv6(void);
void
nd6_lookup_ipv6(void)
{
        panic("nd6_lookup_ipv6() doesn't exist on this platform\n");
}

int
in6addr_local(__unused struct in6_addr *a)
{
        panic("in6addr_local() doesn't exist on this platform\n");
        return (0);
}

void nd6_storelladdr(void);
void
nd6_storelladdr(void)
{
        panic("nd6_storelladdr() doesn't exist on this platform\n");
}
#endif /* INET6 */

/*
 * Mbuf tag KPIs
 */

#define MTAG_FIRST_ID FIRST_KPI_STR_ID

errno_t
mbuf_tag_id_find(
        const char              *string,
        mbuf_tag_id_t   *out_id)
{
        return net_str_id_find_internal(string, out_id, NSI_MBUF_TAG, 1);
}

errno_t
mbuf_tag_allocate(
        mbuf_t                  mbuf,
        mbuf_tag_id_t   id,
        mbuf_tag_type_t type,
        size_t                  length,
        mbuf_how_t              how,
        void**                  data_p)
{
        struct m_tag *tag;
        u_int32_t mtag_id_first, mtag_id_last;
        
        if (data_p != NULL)
                *data_p = NULL;
        
        /* Sanity check parameters */
        (void) net_str_id_first_last(&mtag_id_first, &mtag_id_last, NSI_MBUF_TAG);
        if (mbuf == NULL || (mbuf->m_flags & M_PKTHDR) == 0 || id < mtag_id_first ||
                id > mtag_id_last || length < 1 || (length & 0xffff0000) != 0 ||
                data_p == NULL) {
                return EINVAL;
        }
        
        /* Make sure this mtag hasn't already been allocated */
        tag = m_tag_locate(mbuf, id, type, NULL);
        if (tag != NULL) {
                return EEXIST;
        }
        
        /* Allocate an mtag */
        tag = m_tag_create(id, type, length, how, mbuf);
        if (tag == NULL) {
                return how == M_WAITOK ? ENOMEM : EWOULDBLOCK;
        }
        
        /* Attach the mtag and set *data_p */
        m_tag_prepend(mbuf, tag);
        *data_p = tag + 1;
        
        return 0;
}

errno_t
mbuf_tag_find(
        mbuf_t                  mbuf,
        mbuf_tag_id_t   id,
        mbuf_tag_type_t type,
        size_t*                 length,
        void**                  data_p)
{
        struct m_tag *tag;
        u_int32_t mtag_id_first, mtag_id_last;
        
        if (length != NULL)
                *length = 0;
        if (data_p != NULL)
                *data_p = NULL;
        
        /* Sanity check parameters */
        (void) net_str_id_first_last(&mtag_id_first, &mtag_id_last, NSI_MBUF_TAG);
        if (mbuf == NULL || (mbuf->m_flags & M_PKTHDR) == 0 || id < mtag_id_first ||
                id > mtag_id_last || length == NULL || data_p == NULL) {
                return EINVAL;
        }
        
        /* Locate an mtag */
        tag = m_tag_locate(mbuf, id, type, NULL);
        if (tag == NULL) {
                return ENOENT;
        }
        
        /* Copy out the pointer to the data and the lenght value */
        *length = tag->m_tag_len;
        *data_p = tag + 1;
        
        return 0;
}

void
mbuf_tag_free(
        mbuf_t                  mbuf,
        mbuf_tag_id_t   id,
        mbuf_tag_type_t type)
{
        struct m_tag *tag;
        u_int32_t mtag_id_first, mtag_id_last;
        
        /* Sanity check parameters */
        (void) net_str_id_first_last(&mtag_id_first, &mtag_id_last, NSI_MBUF_TAG);
        if (mbuf == NULL || (mbuf->m_flags & M_PKTHDR) == 0 || id < mtag_id_first ||
                id > mtag_id_last)
                return;
        
        tag = m_tag_locate(mbuf, id, type, NULL);
        if (tag == NULL) {
                return;
        }
        
        m_tag_delete(mbuf, tag);
        return;
}

/*
 * Maximum length of driver auxiliary data; keep this small to
 * fit in a single mbuf to avoid wasting memory, rounded down to
 * the nearest 64-bit boundary.  This takes into account mbuf
 * tag-related (m_taghdr + m_tag) as well m_drvaux_tag structs.
 */
#define MBUF_DRVAUX_MAXLEN                                              \
        P2ROUNDDOWN(MLEN - sizeof (struct m_taghdr) -                   \
        M_TAG_ALIGN(sizeof (struct m_drvaux_tag)), sizeof (uint64_t))

errno_t
mbuf_add_drvaux(mbuf_t mbuf, mbuf_how_t how, u_int32_t family,
    u_int32_t subfamily, size_t length, void **data_p)
{
        struct m_drvaux_tag *p;
        struct m_tag *tag;

        if (mbuf == NULL || !(mbuf->m_flags & M_PKTHDR) ||
            length == 0 || length > MBUF_DRVAUX_MAXLEN)
                return (EINVAL);

        if (data_p != NULL)
                *data_p = NULL;

        /* Check if one is already associated */
        if ((tag = m_tag_locate(mbuf, KERNEL_MODULE_TAG_ID,
            KERNEL_TAG_TYPE_DRVAUX, NULL)) != NULL)
                return (EEXIST);

        /* Tag is (m_drvaux_tag + module specific data) */
        if ((tag = m_tag_create(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_DRVAUX,
            sizeof (*p) + length, how, mbuf)) == NULL)
                return ((how == MBUF_WAITOK) ? ENOMEM : EWOULDBLOCK);

        p = (struct m_drvaux_tag *)(tag + 1);
        p->da_family = family;
        p->da_subfamily = subfamily;
        p->da_length = length;

        /* Associate the tag */
        m_tag_prepend(mbuf, tag);

        if (data_p != NULL)
                *data_p = (p + 1);

        return (0);
}

errno_t
mbuf_find_drvaux(mbuf_t mbuf, u_int32_t *family_p, u_int32_t *subfamily_p,
    u_int32_t *length_p, void **data_p)
{
        struct m_drvaux_tag *p;
        struct m_tag *tag;

        if (mbuf == NULL || !(mbuf->m_flags & M_PKTHDR) || data_p == NULL)
                return (EINVAL);

        *data_p = NULL;

        if ((tag = m_tag_locate(mbuf, KERNEL_MODULE_TAG_ID,
            KERNEL_TAG_TYPE_DRVAUX, NULL)) == NULL)
                return (ENOENT);

        /* Must be at least size of m_drvaux_tag */
        VERIFY(tag->m_tag_len >= sizeof (*p));

        p = (struct m_drvaux_tag *)(tag + 1);
        VERIFY(p->da_length > 0 && p->da_length <= MBUF_DRVAUX_MAXLEN);

        if (family_p != NULL)
                *family_p = p->da_family;
        if (subfamily_p != NULL)
                *subfamily_p = p->da_subfamily;
        if (length_p != NULL)
                *length_p = p->da_length;

        *data_p = (p + 1);

        return (0);
}

void
mbuf_del_drvaux(mbuf_t mbuf)
{
        struct m_tag *tag;

        if (mbuf == NULL || !(mbuf->m_flags & M_PKTHDR))
                return;

        if ((tag = m_tag_locate(mbuf, KERNEL_MODULE_TAG_ID,
            KERNEL_TAG_TYPE_DRVAUX, NULL)) != NULL)
                m_tag_delete(mbuf, tag);
}

/* mbuf stats */
void mbuf_stats(struct mbuf_stat *stats)
{
        stats->mbufs = mbstat.m_mbufs;
        stats->clusters = mbstat.m_clusters;
        stats->clfree = mbstat.m_clfree;
        stats->drops = mbstat.m_drops;
        stats->wait = mbstat.m_wait;
        stats->drain = mbstat.m_drain;
        __builtin_memcpy(stats->mtypes, mbstat.m_mtypes, sizeof(stats->mtypes));
        stats->mcfail = mbstat.m_mcfail;
        stats->mpfail = mbstat.m_mpfail;
        stats->msize = mbstat.m_msize;
        stats->mclbytes = mbstat.m_mclbytes;
        stats->minclsize = mbstat.m_minclsize;
        stats->mlen = mbstat.m_mlen;
        stats->mhlen = mbstat.m_mhlen;
        stats->bigclusters = mbstat.m_bigclusters;
        stats->bigclfree = mbstat.m_bigclfree;
        stats->bigmclbytes = mbstat.m_bigmclbytes;
}

errno_t
mbuf_allocpacket(mbuf_how_t how, size_t packetlen, unsigned int *maxchunks, mbuf_t *mbuf)
{
        errno_t error;
        struct mbuf *m;
        unsigned int numpkts = 1;
        unsigned int numchunks = maxchunks ? *maxchunks : 0;

        if (packetlen == 0) {
                error = EINVAL;
                goto out;
        }
        m = m_allocpacket_internal(&numpkts, packetlen, maxchunks ? &numchunks : NULL, how, 1, 0);
        if (m == 0) {
                if (maxchunks && *maxchunks && numchunks > *maxchunks)
                        error = ENOBUFS;
                else
                        error = ENOMEM;
        } else {
                if (maxchunks)
                        *maxchunks = numchunks;
                error = 0;
                *mbuf = m;
        }
out:
        return error;
}

errno_t
mbuf_allocpacket_list(unsigned int numpkts, mbuf_how_t how, size_t packetlen, unsigned int *maxchunks, mbuf_t *mbuf)
{
        errno_t error;
        struct mbuf *m;
        unsigned int numchunks = maxchunks ? *maxchunks : 0;

        if (numpkts == 0) {
                error = EINVAL;
                goto out;
        }
        if (packetlen == 0) {
                error = EINVAL;
                goto out;
        }
        m = m_allocpacket_internal(&numpkts, packetlen, maxchunks ? &numchunks : NULL, how, 1, 0);
        if (m == 0) {
                if (maxchunks && *maxchunks && numchunks > *maxchunks)
                        error = ENOBUFS;
                else
                        error = ENOMEM;
        } else {
                if (maxchunks)
                        *maxchunks = numchunks;
                error = 0;
                *mbuf = m;
        }
out:
        return error;
}



/*
 * mbuf_copyback differs from m_copyback in a few ways:
 * 1) mbuf_copyback will allocate clusters for new mbufs we append
 * 2) mbuf_copyback will grow the last mbuf in the chain if possible
 * 3) mbuf_copyback reports whether or not the operation succeeded
 * 4) mbuf_copyback allows the caller to specify M_WAITOK or M_NOWAIT
 */
errno_t
mbuf_copyback(
        mbuf_t          m,
        size_t          off,
        size_t          len,
        const void      *data,
        mbuf_how_t      how)
{
        size_t  mlen;
        mbuf_t  m_start = m;
        mbuf_t  n;
        int             totlen = 0;
        errno_t         result = 0;
        const char      *cp = data;

        if (m == NULL || len == 0 || data == NULL)
                return EINVAL;
        
        while (off > (mlen = m->m_len)) {
                off -= mlen;
                totlen += mlen;
                if (m->m_next == 0) {
                        n = m_getclr(how, m->m_type);
                        if (n == 0) {
                                result = ENOBUFS;
                                goto out;
                        }
                        n->m_len = MIN(MLEN, len + off);
                        m->m_next = n;
                }
                m = m->m_next;
        }
        
        while (len > 0) {
                mlen = MIN(m->m_len - off, len);
                if (mlen < len && m->m_next == NULL && mbuf_trailingspace(m) > 0) {
                        size_t  grow = MIN(mbuf_trailingspace(m), len - mlen);
                        mlen += grow;
                        m->m_len += grow;
                }
                bcopy(cp, off + (char*)mbuf_data(m), (unsigned)mlen);
                cp += mlen;
                len -= mlen;
                mlen += off;
                off = 0;
                totlen += mlen;
                if (len == 0)
                        break;
                if (m->m_next == 0) {
                        n = m_get(how, m->m_type);
                        if (n == NULL) {
                                result = ENOBUFS;
                                goto out;
                        }
                        if (len > MINCLSIZE) {
                                /* cluter allocation failure is okay, we can grow chain */
                                mbuf_mclget(how, m->m_type, &n);
                        }
                        n->m_len = MIN(mbuf_maxlen(n), len);
                        m->m_next = n;
                }
                m = m->m_next;
        }
        
out:
        if ((m_start->m_flags & M_PKTHDR) && (m_start->m_pkthdr.len < totlen))
                m_start->m_pkthdr.len = totlen;
        
        return result;
}

u_int32_t
mbuf_get_mlen(void)
{
        return (_MLEN);
}

u_int32_t
mbuf_get_mhlen(void)
{
        return (_MHLEN);
}

u_int32_t
mbuf_get_minclsize(void)
{
        return (MHLEN + MLEN);
}

u_int32_t
mbuf_get_traffic_class_max_count(void)
{
        return (MBUF_TC_MAX);
}

errno_t
mbuf_get_traffic_class_index(mbuf_traffic_class_t tc, u_int32_t *index)
{
        if (index == NULL || (u_int32_t)tc >= MBUF_TC_MAX)
                return (EINVAL);

        *index = MBUF_SCIDX(m_service_class_from_val(MBUF_TC2SCVAL(tc)));
        return (0);
}

mbuf_traffic_class_t
mbuf_get_traffic_class(mbuf_t m)
{
        if (m == NULL || !(m->m_flags & M_PKTHDR))
                return (MBUF_TC_BE);

        return (m_get_traffic_class(m));
}

errno_t
mbuf_set_traffic_class(mbuf_t m, mbuf_traffic_class_t tc)
{
        if (m == NULL || !(m->m_flags & M_PKTHDR) ||
            ((u_int32_t)tc >= MBUF_TC_MAX))
                return (EINVAL);

        return (m_set_traffic_class(m, tc));
}

int
mbuf_is_traffic_class_privileged(mbuf_t m)
{
        if (m == NULL || !(m->m_flags & M_PKTHDR) ||
            !MBUF_VALID_SC(m->m_pkthdr.pkt_svc))
                return (0);

        return ((m->m_pkthdr.pkt_flags & PKTF_PRIO_PRIVILEGED) ? 1 : 0);
}

u_int32_t
mbuf_get_service_class_max_count(void)
{
        return (MBUF_SC_MAX_CLASSES);
}

errno_t
mbuf_get_service_class_index(mbuf_svc_class_t sc, u_int32_t *index)
{
        if (index == NULL || !MBUF_VALID_SC(sc))
                return (EINVAL);

        *index = MBUF_SCIDX(sc);
        return (0);
}

mbuf_svc_class_t
mbuf_get_service_class(mbuf_t m)
{
        if (m == NULL || !(m->m_flags & M_PKTHDR))
                return (MBUF_SC_BE);

        return (m_get_service_class(m));
}

errno_t
mbuf_set_service_class(mbuf_t m, mbuf_svc_class_t sc)
{
        if (m == NULL || !(m->m_flags & M_PKTHDR))
                return (EINVAL);

        return (m_set_service_class(m, sc));
}

errno_t
mbuf_pkthdr_aux_flags(mbuf_t m, mbuf_pkthdr_aux_flags_t *flagsp)
{
        u_int32_t flags;

        if (m == NULL || !(m->m_flags & M_PKTHDR) || flagsp == NULL)
                return (EINVAL);

        *flagsp = 0;
        flags = m->m_pkthdr.pkt_flags;
        if ((flags & (PKTF_INET_RESOLVE|PKTF_RESOLVE_RTR)) ==
            (PKTF_INET_RESOLVE|PKTF_RESOLVE_RTR))
                *flagsp |= MBUF_PKTAUXF_INET_RESOLVE_RTR;
        if ((flags & (PKTF_INET6_RESOLVE|PKTF_RESOLVE_RTR)) ==
            (PKTF_INET6_RESOLVE|PKTF_RESOLVE_RTR))
                *flagsp |= MBUF_PKTAUXF_INET6_RESOLVE_RTR;

        /* These 2 flags are mutually exclusive */
        VERIFY((*flagsp &
            (MBUF_PKTAUXF_INET_RESOLVE_RTR | MBUF_PKTAUXF_INET6_RESOLVE_RTR)) !=
            (MBUF_PKTAUXF_INET_RESOLVE_RTR | MBUF_PKTAUXF_INET6_RESOLVE_RTR));

        return (0);
}

errno_t
mbuf_get_driver_scratch(mbuf_t m, u_int8_t **area, size_t *area_len)
{
        if (m == NULL || area == NULL || area_len == NULL ||
            !(m->m_flags & M_PKTHDR))
                return (EINVAL);

        *area_len = m_scratch_get(m, area);
        return (0);
}