[apple/xnu.git] / bsd / net / ether_if_module.c

/*
 * Copyright (c) 2000-2009 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
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 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1982, 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */



#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>

#include <pexpert/pexpert.h>

#define etherbroadcastaddr      fugly
#include <net/if.h>
#include <net/route.h>
#include <net/if_llc.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/if_ether.h>
#include <netinet/if_ether.h>
#include <netinet/in.h> /* For M_LOOP */
#include <net/kpi_interface.h>
#include <net/kpi_protocol.h>
#undef etherbroadcastaddr

/*
#if INET
#include <netinet/in.h>
#include <netinet/in_var.h>

#include <netinet/in_systm.h>
#include <netinet/ip.h>
#endif
*/
#include <net/ether_if_module.h>
#include <sys/socketvar.h>
#include <net/if_vlan_var.h>
#include <net/if_bond_var.h>
#if IF_BRIDGE
#include <net/if_bridgevar.h>
#endif

#include <net/dlil.h>

#if LLC && CCITT
extern struct ifqueue pkintrq;
#endif

/* General stuff from if_ethersubr.c - may not need some of it */

#include <netat/at_pat.h>
#if NETAT
extern struct ifqueue atalkintrq;
#endif


#define memcpy(x,y,z)   bcopy(y, x, z)


SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW|CTLFLAG_LOCKED, 0, "Ethernet");

struct en_desc {
        u_int16_t       type;                   /* Type of protocol stored in data */
        u_int32_t               protocol_family;        /* Protocol family */
        u_int32_t               data[2];                /* Protocol data */
};

/* descriptors are allocated in blocks of ETHER_DESC_BLK_SIZE */
#if CONFIG_EMBEDDED
#define ETHER_DESC_BLK_SIZE (2) /* IP, ARP */
#else
#define ETHER_DESC_BLK_SIZE (10)
#endif

/*
 * Header for the demux list, hangs off of IFP at family_cookie
 */

struct ether_desc_blk_str {
        u_int32_t  n_max_used;
        u_int32_t       n_count;
        u_int32_t       n_used;
        struct en_desc  block_ptr[1];
};
/* Size of the above struct before the array of struct en_desc */
#define ETHER_DESC_HEADER_SIZE  ((size_t)offsetof(struct ether_desc_blk_str, block_ptr))
__private_extern__ u_char       etherbroadcastaddr[ETHER_ADDR_LEN] =
                                                                { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

static __inline__ int
_ether_cmp(const void * a, const void * b)
{
        const u_int16_t * a_s = (const u_int16_t *)a;
        const u_int16_t * b_s = (const u_int16_t *)b;
        
        if (a_s[0] != b_s[0]
            || a_s[1] != b_s[1]
            || a_s[2] != b_s[2]) {
                return (1);
        }
        return (0);
}

/*
 * Release all descriptor entries owned by this protocol (there may be several).
 * Setting the type to 0 releases the entry. Eventually we should compact-out
 * the unused entries.
 */
int
ether_del_proto(
        ifnet_t ifp,
        protocol_family_t protocol_family)
{
        struct ether_desc_blk_str *desc_blk = (struct ether_desc_blk_str *)ifp->family_cookie;
        u_int32_t       current = 0;
        int found = 0;
        
        if (desc_blk == NULL)
                return 0;
        
        for (current = desc_blk->n_max_used; current > 0; current--) {
                if (desc_blk->block_ptr[current - 1].protocol_family == protocol_family) {
                        found = 1;
                        desc_blk->block_ptr[current - 1].type = 0;
                        desc_blk->n_used--;
                }
        }
        
        if (desc_blk->n_used == 0) {
                FREE(ifp->family_cookie, M_IFADDR);
                ifp->family_cookie = 0;
        }
        else {
                /* Decrement n_max_used */
                for (; desc_blk->n_max_used > 0 && desc_blk->block_ptr[desc_blk->n_max_used - 1].type == 0; desc_blk->n_max_used--)
                        ;
        }
        
        return 0;
 }


static int
ether_add_proto_internal(
        struct ifnet                                    *ifp,
        protocol_family_t                               protocol,
        const struct ifnet_demux_desc   *demux)
{
        struct en_desc *ed;
        struct ether_desc_blk_str *desc_blk = (struct ether_desc_blk_str *)ifp->family_cookie;
        u_int32_t i;
        
        switch (demux->type) {
                /* These types are supported */
                /* Top three are preferred */
                case DLIL_DESC_ETYPE2:
                        if (demux->datalen != 2) {
                                return EINVAL;
                        }
                        break;
                
                case DLIL_DESC_SAP:
                        if (demux->datalen != 3) {
                                return EINVAL;
                        }
                        break;
                
                case DLIL_DESC_SNAP:
                        if (demux->datalen != 5) {
                                return EINVAL;
                        }
                        break;
                        
                default:
                        return ENOTSUP;
        }
        
        // Verify a matching descriptor does not exist.
        if (desc_blk != NULL) {
                switch (demux->type) {
                        case DLIL_DESC_ETYPE2:
                                for (i = 0; i < desc_blk->n_max_used; i++) {
                                        if (desc_blk->block_ptr[i].type == DLIL_DESC_ETYPE2 &&
                                                desc_blk->block_ptr[i].data[0] ==
                                                *(u_int16_t*)demux->data) {
                                                return EADDRINUSE;
                                        }
                                }
                                break;
                        case DLIL_DESC_SAP:
                        case DLIL_DESC_SNAP:
                                for (i = 0; i < desc_blk->n_max_used; i++) {
                                        if (desc_blk->block_ptr[i].type == demux->type &&
                                                bcmp(desc_blk->block_ptr[i].data, demux->data,
                                                         demux->datalen) == 0) {
                                                return EADDRINUSE;
                                        }
                                }
                                break;
                }
        }
        
        // Check for case where all of the descriptor blocks are in use
        if (desc_blk == NULL || desc_blk->n_used == desc_blk->n_count) {
                struct ether_desc_blk_str *tmp;
                u_int32_t       new_count = ETHER_DESC_BLK_SIZE;
                u_int32_t       new_size;
                u_int32_t       old_size = 0;
                
                i = 0;
                
                if (desc_blk) {
                        new_count += desc_blk->n_count;
                        old_size = desc_blk->n_count * sizeof(struct en_desc) + ETHER_DESC_HEADER_SIZE;
                        i = desc_blk->n_used;
                }
                
                new_size = new_count * sizeof(struct en_desc) + ETHER_DESC_HEADER_SIZE;
                
                tmp = _MALLOC(new_size, M_IFADDR, M_WAITOK);
                if (tmp  == 0) {
                        /*
                         * Remove any previous descriptors set in the call.
                         */
                        return ENOMEM;
                }

                bzero(((char *)tmp) + old_size, new_size - old_size);
                if (desc_blk) {
                        bcopy(desc_blk, tmp, old_size);
                        FREE(desc_blk, M_IFADDR);
                }
                desc_blk = tmp;
                ifp->family_cookie = (uintptr_t)desc_blk;
                desc_blk->n_count = new_count;
        }
        else {
                /* Find a free entry */
                for (i = 0; i < desc_blk->n_count; i++) {
                        if (desc_blk->block_ptr[i].type == 0) {
                                break;
                        }
                }
        }
        
        /* Bump n_max_used if appropriate */
        if (i + 1 > desc_blk->n_max_used) {
                desc_blk->n_max_used = i + 1;
        }
        
        ed = &desc_blk->block_ptr[i];
        ed->protocol_family = protocol;
        ed->data[0] = 0;
        ed->data[1] = 0;
        
        switch (demux->type) {
                case DLIL_DESC_ETYPE2:
                        /* 2 byte ethernet raw protocol type is at native_type */
                        /* prtocol must be in network byte order */
                        ed->type = DLIL_DESC_ETYPE2;
                        ed->data[0] = *(u_int16_t*)demux->data;
                        break;
                
                case DLIL_DESC_SAP:
                        ed->type = DLIL_DESC_SAP;
                        bcopy(demux->data, &ed->data[0], 3);
                        break;
                
                case DLIL_DESC_SNAP: {
                        u_int8_t*       pDest = ((u_int8_t*)&ed->data[0]) + 3;
                        ed->type = DLIL_DESC_SNAP;
                        bcopy(demux->data, pDest, 5);
                        }
                        break;
        }
        
        desc_blk->n_used++;
        
        return 0;
}

int
ether_add_proto(
        ifnet_t                         ifp,
        protocol_family_t       protocol,
        const struct ifnet_demux_desc *demux_list,
        u_int32_t                       demux_count)
{
        int                     error = 0;
        u_int32_t       i;
        
        for (i = 0; i < demux_count; i++) {
                error = ether_add_proto_internal(ifp, protocol, &demux_list[i]);
                if (error) {
                        ether_del_proto(ifp, protocol);
                        break;
                }
        }
        
        return error;
}

int
ether_demux(
        ifnet_t                         ifp,
        mbuf_t                          m,
        char                            *frame_header,
        protocol_family_t       *protocol_family)
{
        struct ether_header *eh = (struct ether_header *)frame_header;
        u_short                 ether_type = eh->ether_type;
        u_int16_t               type;
        u_int8_t                *data;
        u_int32_t                       i = 0;
        struct ether_desc_blk_str *desc_blk = (struct ether_desc_blk_str *)ifp->family_cookie;
        u_int32_t                       maxd = desc_blk ? desc_blk->n_max_used : 0;
        struct en_desc  *ed = desc_blk ? desc_blk->block_ptr : NULL;
        u_int32_t               extProto1 = 0;
        u_int32_t               extProto2 = 0;

        if (eh->ether_dhost[0] & 1) {
                /* Check for broadcast */
                if (_ether_cmp(etherbroadcastaddr, eh->ether_dhost) == 0)
                        m->m_flags |= M_BCAST;
                else
                        m->m_flags |= M_MCAST;
        }

        if (ifp->if_eflags & IFEF_BOND) {
                /* if we're bonded, bond "protocol" gets all the packets */
                *protocol_family = PF_BOND;
                return (0);
        }

        if ((eh->ether_dhost[0] & 1) == 0) {
                /*
                 * When the driver is put into promiscuous mode we may receive unicast
                 * frames that are not intended for our interfaces.  They are marked here
                 * as being promiscuous so the caller may dispose of them after passing
                 * the packets to any interface filters.
                 */
                if (_ether_cmp(eh->ether_dhost, ifnet_lladdr(ifp))) {
                        m->m_flags |= M_PROMISC;
                }
        }
        
        /* check for VLAN */
        if ((m->m_pkthdr.csum_flags & CSUM_VLAN_TAG_VALID) != 0) {
                if (EVL_VLANOFTAG(m->m_pkthdr.vlan_tag) != 0) {
                        *protocol_family = PF_VLAN;
                        return (0);
                }
                /* the packet is just priority-tagged, clear the bit */
                m->m_pkthdr.csum_flags &= ~CSUM_VLAN_TAG_VALID;
        }
        else if (ether_type == htons(ETHERTYPE_VLAN)) {
                struct ether_vlan_header *      evl;

                evl = (struct ether_vlan_header *)frame_header;
                if (m->m_len < ETHER_VLAN_ENCAP_LEN
                    || ntohs(evl->evl_proto) == ETHERTYPE_VLAN
                    || EVL_VLANOFTAG(ntohs(evl->evl_tag)) != 0) {
                        *protocol_family = PF_VLAN;
                        return 0;
                }
                /* the packet is just priority-tagged */

                /* make the encapsulated ethertype the actual ethertype */
                ether_type = evl->evl_encap_proto = evl->evl_proto;

                /* remove the encapsulation header */
                m->m_len -= ETHER_VLAN_ENCAP_LEN;
                m->m_data += ETHER_VLAN_ENCAP_LEN;
                m->m_pkthdr.len -= ETHER_VLAN_ENCAP_LEN;
                m->m_pkthdr.csum_flags = 0; /* can't trust hardware checksum */
        }
        
        data = mtod(m, u_int8_t*);
        
        /*
        * Determine the packet's protocol type and stuff the protocol into
        * longs for quick compares.
        */
        
        if (ntohs(ether_type) <= 1500) {
                extProto1 = *(u_int32_t*)data;
                
                // SAP or SNAP
                if ((extProto1 & htonl(0xFFFFFF00)) == htonl(0xAAAA0300)) {
                        // SNAP
                        type = DLIL_DESC_SNAP;
                        extProto2 = *(u_int32_t*)(data + sizeof(u_int32_t));
                        extProto1 &= htonl(0x000000FF);
                } else {
                        type = DLIL_DESC_SAP;
                        extProto1 &= htonl(0xFFFFFF00);
                }
        } else {
                type = DLIL_DESC_ETYPE2;
        }
        
        /* 
        * Search through the connected protocols for a match. 
        */
        
        switch (type) {
                case DLIL_DESC_ETYPE2:
                        for (i = 0; i < maxd; i++) {
                                if ((ed[i].type == type) && (ed[i].data[0] == ether_type)) {
                                        *protocol_family = ed[i].protocol_family;
                                        return 0;
                                }
                        }
                        break;
                
                case DLIL_DESC_SAP:
                        for (i = 0; i < maxd; i++) {
                                if ((ed[i].type == type) && (ed[i].data[0] == extProto1)) {
                                        *protocol_family = ed[i].protocol_family;
                                        return 0;
                                }
                        }
                        break;
                
                case DLIL_DESC_SNAP:
                        for (i = 0; i < maxd; i++) {
                                if ((ed[i].type == type) && (ed[i].data[0] == extProto1) &&
                                        (ed[i].data[1] == extProto2)) {
                                        *protocol_family = ed[i].protocol_family;
                                        return 0;
                                }
                        }
                break;
        }
        
        return ENOENT;
}                       

/*
 * Ethernet output routine.
 * Encapsulate a packet of type family for the local net.
 * Use trailer local net encapsulation if enough data in first
 * packet leaves a multiple of 512 bytes of data in remainder.
 */
int
ether_frameout(
        struct ifnet                    *ifp,
        struct mbuf                             **m,
        const struct sockaddr   *ndest,
        const char                              *edst,
        const char                              *ether_type)
{
        struct ether_header *eh;
        int hlen;       /* link layer header length */

        hlen = ETHER_HDR_LEN;

        /*
         * If a simplex interface, and the packet is being sent to our
         * Ethernet address or a broadcast address, loopback a copy.
         * XXX To make a simplex device behave exactly like a duplex
         * device, we should copy in the case of sending to our own
         * ethernet address (thus letting the original actually appear
         * on the wire). However, we don't do that here for security
         * reasons and compatibility with the original behavior.
         */
        if ((ifp->if_flags & IFF_SIMPLEX) &&
            ((*m)->m_flags & M_LOOP)) {
            if (lo_ifp) {
            if ((*m)->m_flags & M_BCAST) {
                struct mbuf *n = m_copy(*m, 0, (int)M_COPYALL);
                if (n != NULL)
                    dlil_output(lo_ifp, ndest->sa_family, n, NULL, ndest, 0);
            }
            else {
                                        if (_ether_cmp(edst, ifnet_lladdr(ifp)) == 0) {
                    dlil_output(lo_ifp, ndest->sa_family, *m, NULL, ndest, 0);
                    return EJUSTRETURN;
                }
            }
            }
        }
    
        /*
         * Add local net header.  If no space in first mbuf,
         * allocate another.
         */
        M_PREPEND(*m, sizeof (struct ether_header), M_DONTWAIT);
        if (*m == 0) {
            return (EJUSTRETURN);
        }


        eh = mtod(*m, struct ether_header *);
        (void)memcpy(&eh->ether_type, ether_type,
                sizeof(eh->ether_type));
        (void)memcpy(eh->ether_dhost, edst, ETHER_ADDR_LEN);
        ifnet_lladdr_copy_bytes(ifp, eh->ether_shost, ETHER_ADDR_LEN);

        return 0;
}

errno_t
ether_check_multi(
        __unused ifnet_t                ifp,
        const struct sockaddr   *proto_addr)
{
        errno_t result = EAFNOSUPPORT;
        const u_char *e_addr;
        
        /*
         * AF_SPEC and AF_LINK don't require translation. We do
         * want to verify that they specify a valid multicast.
         */
        switch(proto_addr->sa_family) {
                case AF_UNSPEC:
                        e_addr = (const u_char*)&proto_addr->sa_data[0];
                        if ((e_addr[0] & 0x01) != 0x01)
                                result = EADDRNOTAVAIL;
                        else
                                result = 0;
                        break;
                
                case AF_LINK:
                        e_addr = CONST_LLADDR((const struct sockaddr_dl*)proto_addr); 
                        if ((e_addr[0] & 0x01) != 0x01)
                                result = EADDRNOTAVAIL;
                        else
                                result = 0;
                        break;
        }
        
        return result;
}

int
ether_ioctl(
    __unused ifnet_t    ifp,
    __unused u_int32_t  command,
    __unused void*              data)
{
        return EOPNOTSUPP;
}

__private_extern__ int ether_family_init(void)
{
        errno_t error = 0;
        
        /* Register protocol registration functions */
        if ((error = proto_register_plumber(PF_INET, APPLE_IF_FAM_ETHERNET,
                                                                          ether_attach_inet, ether_detach_inet)) != 0) {
                printf("proto_register_plumber failed for PF_INET error=%d\n", error);
                goto done;
        }
#if INET6
        if ((error = proto_register_plumber(PF_INET6, APPLE_IF_FAM_ETHERNET,
                                                                          ether_attach_inet6, ether_detach_inet6)) != 0) {
                printf("proto_register_plumber failed for PF_INET6 error=%d\n", error);
                goto done;
        }
#endif /* INET6 */
#if NETAT
        if ((error = proto_register_plumber(PF_APPLETALK, APPLE_IF_FAM_ETHERNET,
                                                                          ether_attach_at, ether_detach_at)) != 0) {
                printf("proto_register_plumber failed PF_APPLETALK error=%d\n", error);
                goto done;
        }
#endif /* NETAT */
#if VLAN
        vlan_family_init();
#endif /* VLAN */
#if BOND
        bond_family_init();
#endif /* BOND */
#if IF_BRIDGE
        bridgeattach(0);
#endif

 done:

    return (error);
}