/* * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved. * * @APPLE_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. 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_LICENSE_HEADER_END@ */ /* * Copyright (c) 1990, 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from the Stanford/CMU enet packet filter, * (net/enet.c) distributed as part of 4.3BSD, and code contributed * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence * Berkeley Laboratory. * * 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. * * @(#)bpf.c 8.2 (Berkeley) 3/28/94 * * $FreeBSD: src/sys/net/bpf.c,v 1.59.2.5 2001/01/05 04:49:09 jdp Exp $ */ #include "bpf.h" #ifndef __GNUC__ #define inline #else #define inline __inline #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(sparc) && BSD < 199103 #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern int tvtohz(struct timeval *); #if NBPFILTER > 0 /* * Older BSDs don't have kernel malloc. */ #if BSD < 199103 extern bcopy(); static caddr_t bpf_alloc(); #include #define BPF_BUFSIZE (MCLBYTES-8) #define UIOMOVE(cp, len, code, uio) uiomove(cp, len, code, uio) #else #define BPF_BUFSIZE 4096 #define UIOMOVE(cp, len, code, uio) uiomove(cp, len, uio) #endif #define PRINET 26 /* interruptible */ /* * The default read buffer size is patchable. */ static unsigned int bpf_bufsize = BPF_BUFSIZE; SYSCTL_INT(_debug, OID_AUTO, bpf_bufsize, CTLFLAG_RW, &bpf_bufsize, 0, ""); static unsigned int bpf_maxbufsize = BPF_MAXBUFSIZE; SYSCTL_INT(_debug, OID_AUTO, bpf_maxbufsize, CTLFLAG_RW, &bpf_maxbufsize, 0, ""); static unsigned int bpf_maxdevices = 256; SYSCTL_UINT(_debug, OID_AUTO, bpf_maxdevices, CTLFLAG_RW, &bpf_maxdevices, 0, ""); /* * bpf_iflist is the list of interfaces; each corresponds to an ifnet * bpf_dtab holds pointer to the descriptors, indexed by minor device # */ static struct bpf_if *bpf_iflist; #ifdef __APPLE__ /* * BSD now stores the bpf_d in the dev_t which is a struct * on their system. Our dev_t is an int, so we still store * the bpf_d in a separate table indexed by minor device #. * * The value stored in bpf_dtab[n] represent three states: * 0: device not opened * 1: device opening or closing * other: device opened with pointer to storage */ static struct bpf_d **bpf_dtab = NULL; static unsigned int bpf_dtab_size = 0; static unsigned int nbpfilter = 0; static lck_mtx_t *bpf_mlock; static lck_grp_t *bpf_mlock_grp; static lck_grp_attr_t *bpf_mlock_grp_attr; static lck_attr_t *bpf_mlock_attr; /* * Mark a descriptor free by making it point to itself. * This is probably cheaper than marking with a constant since * the address should be in a register anyway. */ #endif /* __APPLE__ */ static int bpf_allocbufs(struct bpf_d *); static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp); static void bpf_detachd(struct bpf_d *d); static void bpf_freed(struct bpf_d *); static void bpf_mcopy(const void *, void *, size_t); static int bpf_movein(struct uio *, int, struct mbuf **, struct sockaddr *, int *); static int bpf_setif(struct bpf_d *, struct ifreq *); static void bpf_wakeup(struct bpf_d *); static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, void (*)(const void *, void *, size_t)); static void reset_d(struct bpf_d *); static int bpf_setf(struct bpf_d *, struct user_bpf_program *); /*static void *bpf_devfs_token[MAXBPFILTER];*/ static int bpf_devsw_installed; void bpf_init(void *unused); int bpf_tap_callback(struct ifnet *ifp, struct mbuf *m); /* * Darwin differs from BSD here, the following are static * on BSD and not static on Darwin. */ d_open_t bpfopen; d_close_t bpfclose; d_read_t bpfread; d_write_t bpfwrite; ioctl_fcn_t bpfioctl; select_fcn_t bpfpoll; /* Darwin's cdevsw struct differs slightly from BSDs */ #define CDEV_MAJOR 23 static struct cdevsw bpf_cdevsw = { /* open */ bpfopen, /* close */ bpfclose, /* read */ bpfread, /* write */ bpfwrite, /* ioctl */ bpfioctl, /* stop */ eno_stop, /* reset */ eno_reset, /* tty */ NULL, /* select */ bpfpoll, /* mmap */ eno_mmap, /* strategy*/ eno_strat, /* getc */ eno_getc, /* putc */ eno_putc, /* type */ 0 }; #define SOCKADDR_HDR_LEN offsetof(struct sockaddr, sa_data) static int bpf_movein(struct uio *uio, int linktype, struct mbuf **mp, struct sockaddr *sockp, int *datlen) { struct mbuf *m; int error; int len; int hlen; if (sockp) { /* * Build a sockaddr based on the data link layer type. * We do this at this level because the ethernet header * is copied directly into the data field of the sockaddr. * In the case of SLIP, there is no header and the packet * is forwarded as is. * Also, we are careful to leave room at the front of the mbuf * for the link level header. */ switch (linktype) { case DLT_SLIP: sockp->sa_family = AF_INET; hlen = 0; break; case DLT_EN10MB: sockp->sa_family = AF_UNSPEC; /* XXX Would MAXLINKHDR be better? */ hlen = sizeof(struct ether_header); break; case DLT_FDDI: #if defined(__FreeBSD__) || defined(__bsdi__) sockp->sa_family = AF_IMPLINK; hlen = 0; #else sockp->sa_family = AF_UNSPEC; /* XXX 4(FORMAC)+6(dst)+6(src)+3(LLC)+5(SNAP) */ hlen = 24; #endif break; case DLT_RAW: case DLT_NULL: sockp->sa_family = AF_UNSPEC; hlen = 0; break; #ifdef __FreeBSD__ case DLT_ATM_RFC1483: /* * en atm driver requires 4-byte atm pseudo header. * though it isn't standard, vpi:vci needs to be * specified anyway. */ sockp->sa_family = AF_UNSPEC; hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ break; #endif case DLT_PPP: sockp->sa_family = AF_UNSPEC; hlen = 4; /* This should match PPP_HDRLEN */ break; case DLT_APPLE_IP_OVER_IEEE1394: sockp->sa_family = AF_UNSPEC; hlen = sizeof(struct firewire_header); break; default: return (EIO); } if ((hlen + SOCKADDR_HDR_LEN) > sockp->sa_len) { return (EIO); } } else { hlen = 0; } // LP64todo - fix this! len = uio_resid(uio); *datlen = len - hlen; if ((unsigned)len > MCLBYTES) return (EIO); MGETHDR(m, M_WAIT, MT_DATA); if (m == 0) return (ENOBUFS); if ((unsigned)len > MHLEN) { #if BSD >= 199103 MCLGET(m, M_WAIT); if ((m->m_flags & M_EXT) == 0) { #else MCLGET(m); if (m->m_len != MCLBYTES) { #endif error = ENOBUFS; goto bad; } } m->m_pkthdr.len = m->m_len = len; m->m_pkthdr.rcvif = NULL; *mp = m; /* * Make room for link header. */ if (hlen != 0) { m->m_pkthdr.len -= hlen; m->m_len -= hlen; #if BSD >= 199103 m->m_data += hlen; /* XXX */ #else m->m_off += hlen; #endif error = UIOMOVE((caddr_t)sockp->sa_data, hlen, UIO_WRITE, uio); if (error) goto bad; } error = UIOMOVE(mtod(m, caddr_t), len - hlen, UIO_WRITE, uio); if (!error) return (0); bad: m_freem(m); return (error); } #ifdef __APPLE__ /* Callback registered with Ethernet driver. */ int bpf_tap_callback(struct ifnet *ifp, struct mbuf *m) { /* * Do nothing if the BPF tap has been turned off. * This is to protect from a potential race where this * call blocks on the lock. And in the meantime * BPF is turned off, which will clear if_bpf. */ if (ifp->if_bpf) bpf_mtap(ifp, m); return 0; } /* * The dynamic addition of a new device node must block all processes that are opening * the last device so that no process will get an unexpected ENOENT */ static void bpf_make_dev_t(int maj) { static int bpf_growing = 0; unsigned int cur_size = nbpfilter, i; if (nbpfilter >= bpf_maxdevices) return; while (bpf_growing) { /* Wait until new device has been created */ (void)tsleep((caddr_t)&bpf_growing, PZERO, "bpf_growing", 0); } if (nbpfilter > cur_size) { /* other thread grew it already */ return; } bpf_growing = 1; /* need to grow bpf_dtab first */ if (nbpfilter == bpf_dtab_size) { int new_dtab_size; struct bpf_d **new_dtab = NULL; struct bpf_d **old_dtab = NULL; new_dtab_size = bpf_dtab_size + NBPFILTER; new_dtab = (struct bpf_d **)_MALLOC(sizeof(struct bpf_d *) * new_dtab_size, M_DEVBUF, M_WAIT); if (new_dtab == 0) { printf("bpf_make_dev_t: malloc bpf_dtab failed\n"); goto done; } if (bpf_dtab) { bcopy(bpf_dtab, new_dtab, sizeof(struct bpf_d *) * bpf_dtab_size); } bzero(new_dtab + bpf_dtab_size, sizeof(struct bpf_d *) * NBPFILTER); old_dtab = bpf_dtab; bpf_dtab = new_dtab; bpf_dtab_size = new_dtab_size; if (old_dtab != NULL) _FREE(old_dtab, M_DEVBUF); } i = nbpfilter++; (void) devfs_make_node(makedev(maj, i), DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0600, "bpf%d", i); done: bpf_growing = 0; wakeup((caddr_t)&bpf_growing); } #endif /* * Attach file to the bpf interface, i.e. make d listen on bp. * Must be called at splimp. */ static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp) { /* * Point d at bp, and add d to the interface's list of listeners. * Finally, point the driver's bpf cookie at the interface so * it will divert packets to bpf. */ d->bd_bif = bp; d->bd_next = bp->bif_dlist; bp->bif_dlist = d; bp->bif_ifp->if_bpf = bp; #ifdef __APPLE__ dlil_set_bpf_tap(bp->bif_ifp, BPF_TAP_INPUT_OUTPUT, bpf_tap_callback); #endif } /* * Detach a file from its interface. */ static void bpf_detachd(struct bpf_d *d) { struct bpf_d **p; struct bpf_if *bp; #ifdef __APPLE__ struct ifnet *ifp; ifp = d->bd_bif->bif_ifp; #endif bp = d->bd_bif; /* * Check if this descriptor had requested promiscuous mode. * If so, turn it off. */ if (d->bd_promisc) { d->bd_promisc = 0; if (ifnet_set_promiscuous(bp->bif_ifp, 0)) /* * Something is really wrong if we were able to put * the driver into promiscuous mode, but can't * take it out. * Most likely the network interface is gone. */ printf("bpf: ifnet_set_promiscuous failed"); } /* Remove d from the interface's descriptor list. */ p = &bp->bif_dlist; while (*p != d) { p = &(*p)->bd_next; if (*p == 0) panic("bpf_detachd: descriptor not in list"); } *p = (*p)->bd_next; if (bp->bif_dlist == 0) { /* * Let the driver know that there are no more listeners. */ if (ifp->if_set_bpf_tap) (*ifp->if_set_bpf_tap)(ifp, BPF_TAP_DISABLE, 0); d->bd_bif->bif_ifp->if_bpf = 0; } d->bd_bif = 0; } /* * Open ethernet device. Returns ENXIO for illegal minor device number, * EBUSY if file is open by another process. */ /* ARGSUSED */ int bpfopen(dev_t dev, __unused int flags, __unused int fmt, __unused struct proc *p) { register struct bpf_d *d; if ((unsigned int) minor(dev) >= nbpfilter) return (ENXIO); /* * New device nodes are created on demand when opening the last one. * The programming model is for processes to loop on the minor starting at 0 * as long as EBUSY is returned. The loop stops when either the open succeeds or * an error other that EBUSY is returned. That means that bpf_make_dev_t() must * block all processes that are opening the last node. If not all * processes are blocked, they could unexpectedly get ENOENT and abort their * opening loop. */ if ((unsigned int) minor(dev) == (nbpfilter - 1)) bpf_make_dev_t(major(dev)); /* * Each minor can be opened by only one process. If the requested * minor is in use, return EBUSY. * * Important: bpfopen() and bpfclose() have to check and set the status of a device * in the same lockin context otherwise the device may be leaked because the vnode use count * will be unpextectly greater than 1 when close() is called. */ if (bpf_dtab[minor(dev)] == 0) bpf_dtab[minor(dev)] = (void *)1; /* Mark opening */ else return (EBUSY); d = (struct bpf_d *)_MALLOC(sizeof(struct bpf_d), M_DEVBUF, M_WAIT); if (d == NULL) { /* this really is a catastrophic failure */ printf("bpfopen: malloc bpf_d failed\n"); bpf_dtab[minor(dev)] = 0; return ENOMEM; } bzero(d, sizeof(struct bpf_d)); /* * It is not necessary to take the BPF lock here because no other * thread can access the device until it is marked opened... */ /* Mark "in use" and do most initialization. */ d->bd_bufsize = bpf_bufsize; d->bd_sig = SIGIO; d->bd_seesent = 1; bpf_dtab[minor(dev)] = d; /* Mark opened */ return (0); } /* * Close the descriptor by detaching it from its interface, * deallocating its buffers, and marking it free. */ /* ARGSUSED */ int bpfclose(dev_t dev, __unused int flags, __unused int fmt, __unused struct proc *p) { register struct bpf_d *d; d = bpf_dtab[minor(dev)]; if (d == 0 || d == (void *)1) return (ENXIO); bpf_dtab[minor(dev)] = (void *)1; /* Mark closing */ /* Take BPF lock to ensure no other thread is using the device */ lck_mtx_lock(bpf_mlock); if (d->bd_bif) bpf_detachd(d); selthreadclear(&d->bd_sel); bpf_freed(d); lck_mtx_unlock(bpf_mlock); /* Mark free in same context as bpfopen comes to check */ bpf_dtab[minor(dev)] = 0; /* Mark closed */ _FREE(d, M_DEVBUF); return (0); } #define BPF_SLEEP bpf_sleep static int bpf_sleep(struct bpf_d *d, int pri, const char *wmesg, int timo) { register int st; lck_mtx_unlock(bpf_mlock); st = tsleep((caddr_t)d, pri, wmesg, timo); lck_mtx_lock(bpf_mlock); return st; } /* * Rotate the packet buffers in descriptor d. Move the store buffer * into the hold slot, and the free buffer into the store slot. * Zero the length of the new store buffer. */ #define ROTATE_BUFFERS(d) \ (d)->bd_hbuf = (d)->bd_sbuf; \ (d)->bd_hlen = (d)->bd_slen; \ (d)->bd_sbuf = (d)->bd_fbuf; \ (d)->bd_slen = 0; \ (d)->bd_fbuf = 0; /* * bpfread - read next chunk of packets from buffers */ int bpfread(dev_t dev, struct uio *uio, int ioflag) { register struct bpf_d *d; int error; int s; d = bpf_dtab[minor(dev)]; if (d == 0 || d == (void *)1) return (ENXIO); lck_mtx_lock(bpf_mlock); /* * Restrict application to use a buffer the same size as * as kernel buffers. */ // LP64todo - fix this if (uio->uio_resid != d->bd_bufsize) { lck_mtx_unlock(bpf_mlock); return (EINVAL); } s = splimp(); /* * If the hold buffer is empty, then do a timed sleep, which * ends when the timeout expires or when enough packets * have arrived to fill the store buffer. */ while (d->bd_hbuf == 0) { if (d->bd_immediate && d->bd_slen != 0) { /* * A packet(s) either arrived since the previous * read or arrived while we were asleep. * Rotate the buffers and return what's here. */ ROTATE_BUFFERS(d); break; } /* * No data is available, check to see if the bpf device * is still pointed at a real interface. If not, return * ENXIO so that the userland process knows to rebind * it before using it again. */ if (d->bd_bif == NULL) { splx(s); lck_mtx_unlock(bpf_mlock); return (ENXIO); } if (ioflag & IO_NDELAY) error = EWOULDBLOCK; else error = BPF_SLEEP(d, PRINET|PCATCH, "bpf", d->bd_rtout); if (error == EINTR || error == ERESTART) { splx(s); lck_mtx_unlock(bpf_mlock); return (error); } if (error == EWOULDBLOCK) { /* * On a timeout, return what's in the buffer, * which may be nothing. If there is something * in the store buffer, we can rotate the buffers. */ if (d->bd_hbuf) /* * We filled up the buffer in between * getting the timeout and arriving * here, so we don't need to rotate. */ break; if (d->bd_slen == 0) { splx(s); lck_mtx_unlock(bpf_mlock); return (0); } ROTATE_BUFFERS(d); break; } } /* * At this point, we know we have something in the hold slot. */ splx(s); /* * Move data from hold buffer into user space. * We know the entire buffer is transferred since * we checked above that the read buffer is bpf_bufsize bytes. */ error = UIOMOVE(d->bd_hbuf, d->bd_hlen, UIO_READ, uio); s = splimp(); d->bd_fbuf = d->bd_hbuf; d->bd_hbuf = 0; d->bd_hlen = 0; splx(s); lck_mtx_unlock(bpf_mlock); return (error); } /* * If there are processes sleeping on this descriptor, wake them up. */ static void bpf_wakeup(struct bpf_d *d) { wakeup((caddr_t)d); if (d->bd_async && d->bd_sig && d->bd_sigio) pgsigio(d->bd_sigio, d->bd_sig, 0); #if BSD >= 199103 selwakeup(&d->bd_sel); #ifndef __APPLE__ /* XXX */ d->bd_sel.si_pid = 0; #endif #else if (d->bd_selproc) { selwakeup(d->bd_selproc, (int)d->bd_selcoll); d->bd_selcoll = 0; d->bd_selproc = 0; } #endif } /* keep in sync with bpf_movein above: */ #define MAX_DATALINK_HDR_LEN (sizeof(struct firewire_header)) int bpfwrite(dev_t dev, struct uio *uio, __unused int ioflag) { register struct bpf_d *d; struct ifnet *ifp; struct mbuf *m; int error; char dst_buf[SOCKADDR_HDR_LEN + MAX_DATALINK_HDR_LEN]; int datlen; d = bpf_dtab[minor(dev)]; if (d == 0 || d == (void *)1) return (ENXIO); lck_mtx_lock(bpf_mlock); if (d->bd_bif == 0) { lck_mtx_unlock(bpf_mlock); return (ENXIO); } ifp = d->bd_bif->bif_ifp; if (uio->uio_resid == 0) { lck_mtx_unlock(bpf_mlock); return (0); } ((struct sockaddr *)dst_buf)->sa_len = sizeof(dst_buf); error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, &m, d->bd_hdrcmplt ? 0 : (struct sockaddr *)dst_buf, &datlen); if (error) { lck_mtx_unlock(bpf_mlock); return (error); } if ((unsigned)datlen > ifp->if_mtu) { lck_mtx_unlock(bpf_mlock); return (EMSGSIZE); } lck_mtx_unlock(bpf_mlock); if (d->bd_hdrcmplt) { error = dlil_output(ifp, 0, m, NULL, NULL, 1); } else { error = dlil_output(ifp, PF_INET, m, NULL, (struct sockaddr *)dst_buf, 0); } /* * The driver frees the mbuf. */ return (error); } /* * Reset a descriptor by flushing its packet buffer and clearing the * receive and drop counts. Should be called at splimp. */ static void reset_d(struct bpf_d *d) { if (d->bd_hbuf) { /* Free the hold buffer. */ d->bd_fbuf = d->bd_hbuf; d->bd_hbuf = 0; } d->bd_slen = 0; d->bd_hlen = 0; d->bd_rcount = 0; d->bd_dcount = 0; } /* * FIONREAD Check for read packet available. * SIOCGIFADDR Get interface address - convenient hook to driver. * BIOCGBLEN Get buffer len [for read()]. * BIOCSETF Set ethernet read filter. * BIOCFLUSH Flush read packet buffer. * BIOCPROMISC Put interface into promiscuous mode. * BIOCGDLT Get link layer type. * BIOCGETIF Get interface name. * BIOCSETIF Set interface. * BIOCSRTIMEOUT Set read timeout. * BIOCGRTIMEOUT Get read timeout. * BIOCGSTATS Get packet stats. * BIOCIMMEDIATE Set immediate mode. * BIOCVERSION Get filter language version. * BIOCGHDRCMPLT Get "header already complete" flag * BIOCSHDRCMPLT Set "header already complete" flag * BIOCGSEESENT Get "see packets sent" flag * BIOCSSEESENT Set "see packets sent" flag */ /* ARGSUSED */ int bpfioctl(dev_t dev, u_long cmd, caddr_t addr, __unused int flags, struct proc *p) { register struct bpf_d *d; int s, error = 0; d = bpf_dtab[minor(dev)]; if (d == 0 || d == (void *)1) return (ENXIO); lck_mtx_lock(bpf_mlock); switch (cmd) { default: error = EINVAL; break; /* * Check for read packet available. */ case FIONREAD: { int n; s = splimp(); n = d->bd_slen; if (d->bd_hbuf) n += d->bd_hlen; splx(s); *(int *)addr = n; break; } case SIOCGIFADDR: { struct ifnet *ifp; if (d->bd_bif == 0) error = EINVAL; else { ifp = d->bd_bif->bif_ifp; error = dlil_ioctl(0, ifp, cmd, addr); } break; } /* * Get buffer len [for read()]. */ case BIOCGBLEN: *(u_int *)addr = d->bd_bufsize; break; /* * Set buffer length. */ case BIOCSBLEN: #if BSD < 199103 error = EINVAL; #else if (d->bd_bif != 0) error = EINVAL; else { register u_int size = *(u_int *)addr; if (size > bpf_maxbufsize) *(u_int *)addr = size = bpf_maxbufsize; else if (size < BPF_MINBUFSIZE) *(u_int *)addr = size = BPF_MINBUFSIZE; d->bd_bufsize = size; } #endif break; /* * Set link layer read filter. */ case BIOCSETF: if (proc_is64bit(p)) { error = bpf_setf(d, (struct user_bpf_program *)addr); } else { struct bpf_program * tmpp; struct user_bpf_program tmp; tmpp = (struct bpf_program *)addr; tmp.bf_len = tmpp->bf_len; tmp.bf_insns = CAST_USER_ADDR_T(tmpp->bf_insns); error = bpf_setf(d, &tmp); } break; /* * Flush read packet buffer. */ case BIOCFLUSH: s = splimp(); reset_d(d); splx(s); break; /* * Put interface into promiscuous mode. */ case BIOCPROMISC: if (d->bd_bif == 0) { /* * No interface attached yet. */ error = EINVAL; break; } s = splimp(); if (d->bd_promisc == 0) { error = ifnet_set_promiscuous(d->bd_bif->bif_ifp, 1); if (error == 0) d->bd_promisc = 1; } splx(s); break; /* * Get device parameters. */ case BIOCGDLT: if (d->bd_bif == 0) error = EINVAL; else *(u_int *)addr = d->bd_bif->bif_dlt; break; /* * Get interface name. */ case BIOCGETIF: if (d->bd_bif == 0) error = EINVAL; else { struct ifnet *const ifp = d->bd_bif->bif_ifp; struct ifreq *const ifr = (struct ifreq *)addr; snprintf(ifr->ifr_name, sizeof(ifr->ifr_name), "%s%d", ifp->if_name, ifp->if_unit); } break; /* * Set interface. */ case BIOCSETIF: error = bpf_setif(d, (struct ifreq *)addr); break; /* * Set read timeout. */ case BIOCSRTIMEOUT: { struct timeval *tv = (struct timeval *)addr; /* * Subtract 1 tick from tvtohz() since this isn't * a one-shot timer. */ if ((error = itimerfix(tv)) == 0) d->bd_rtout = tvtohz(tv) - 1; break; } /* * Get read timeout. */ case BIOCGRTIMEOUT: { struct timeval *tv = (struct timeval *)addr; tv->tv_sec = d->bd_rtout / hz; tv->tv_usec = (d->bd_rtout % hz) * tick; break; } /* * Get packet stats. */ case BIOCGSTATS: { struct bpf_stat *bs = (struct bpf_stat *)addr; bs->bs_recv = d->bd_rcount; bs->bs_drop = d->bd_dcount; break; } /* * Set immediate mode. */ case BIOCIMMEDIATE: d->bd_immediate = *(u_int *)addr; break; case BIOCVERSION: { struct bpf_version *bv = (struct bpf_version *)addr; bv->bv_major = BPF_MAJOR_VERSION; bv->bv_minor = BPF_MINOR_VERSION; break; } /* * Get "header already complete" flag */ case BIOCGHDRCMPLT: *(u_int *)addr = d->bd_hdrcmplt; break; /* * Set "header already complete" flag */ case BIOCSHDRCMPLT: d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; break; /* * Get "see sent packets" flag */ case BIOCGSEESENT: *(u_int *)addr = d->bd_seesent; break; /* * Set "see sent packets" flag */ case BIOCSSEESENT: d->bd_seesent = *(u_int *)addr; break; case FIONBIO: /* Non-blocking I/O */ break; case FIOASYNC: /* Send signal on receive packets */ d->bd_async = *(int *)addr; break; #ifndef __APPLE__ case FIOSETOWN: error = fsetown(*(int *)addr, &d->bd_sigio); break; case FIOGETOWN: *(int *)addr = fgetown(d->bd_sigio); break; /* This is deprecated, FIOSETOWN should be used instead. */ case TIOCSPGRP: error = fsetown(-(*(int *)addr), &d->bd_sigio); break; /* This is deprecated, FIOGETOWN should be used instead. */ case TIOCGPGRP: *(int *)addr = -fgetown(d->bd_sigio); break; #endif case BIOCSRSIG: /* Set receive signal */ { u_int sig; sig = *(u_int *)addr; if (sig >= NSIG) error = EINVAL; else d->bd_sig = sig; break; } case BIOCGRSIG: *(u_int *)addr = d->bd_sig; break; } lck_mtx_unlock(bpf_mlock); return (error); } /* * Set d's packet filter program to fp. If this file already has a filter, * free it and replace it. Returns EINVAL for bogus requests. */ static int bpf_setf(struct bpf_d *d, struct user_bpf_program *fp) { struct bpf_insn *fcode, *old; u_int flen, size; int s; old = d->bd_filter; if (fp->bf_insns == USER_ADDR_NULL) { if (fp->bf_len != 0) return (EINVAL); s = splimp(); d->bd_filter = 0; reset_d(d); splx(s); if (old != 0) FREE((caddr_t)old, M_DEVBUF); return (0); } flen = fp->bf_len; if (flen > BPF_MAXINSNS) return (EINVAL); size = flen * sizeof(struct bpf_insn); fcode = (struct bpf_insn *) _MALLOC(size, M_DEVBUF, M_WAIT); #ifdef __APPLE__ if (fcode == NULL) return (ENOBUFS); #endif if (copyin(fp->bf_insns, (caddr_t)fcode, size) == 0 && bpf_validate(fcode, (int)flen)) { s = splimp(); d->bd_filter = fcode; reset_d(d); splx(s); if (old != 0) FREE((caddr_t)old, M_DEVBUF); return (0); } FREE((caddr_t)fcode, M_DEVBUF); return (EINVAL); } /* * Detach a file from its current interface (if attached at all) and attach * to the interface indicated by the name stored in ifr. * Return an errno or 0. */ static int bpf_setif(struct bpf_d *d, struct ifreq *ifr) { struct bpf_if *bp; int s, error; struct ifnet *theywant; theywant = ifunit(ifr->ifr_name); if (theywant == 0) return ENXIO; /* * Look through attached interfaces for the named one. */ for (bp = bpf_iflist; bp != 0; bp = bp->bif_next) { struct ifnet *ifp = bp->bif_ifp; if (ifp == 0 || ifp != theywant) continue; /* * We found the requested interface. * If it's not up, return an error. * Allocate the packet buffers if we need to. * If we're already attached to requested interface, * just flush the buffer. */ if ((ifp->if_flags & IFF_UP) == 0) return (ENETDOWN); if (d->bd_sbuf == 0) { error = bpf_allocbufs(d); if (error != 0) return (error); } s = splimp(); if (bp != d->bd_bif) { if (d->bd_bif) /* * Detach if attached to something else. */ bpf_detachd(d); bpf_attachd(d, bp); } reset_d(d); splx(s); return (0); } /* Not found. */ return (ENXIO); } /* * Support for select() and poll() system calls * * Return true iff the specific operation will not block indefinitely. * Otherwise, return false but make a note that a selwakeup() must be done. */ int bpfpoll(dev_t dev, int events, void * wql, struct proc *p) { register struct bpf_d *d; register int s; int revents = 0; d = bpf_dtab[minor(dev)]; if (d == 0 || d == (void *)1) return (ENXIO); lck_mtx_lock(bpf_mlock); /* * An imitation of the FIONREAD ioctl code. */ if (d->bd_bif == NULL) { lck_mtx_unlock(bpf_mlock); return (ENXIO); } s = splimp(); if (events & (POLLIN | POLLRDNORM)) { if (d->bd_hlen != 0 || (d->bd_immediate && d->bd_slen != 0)) revents |= events & (POLLIN | POLLRDNORM); else selrecord(p, &d->bd_sel, wql); } splx(s); lck_mtx_unlock(bpf_mlock); return (revents); } /* * Incoming linkage from device drivers. Process the packet pkt, of length * pktlen, which is stored in a contiguous buffer. The packet is parsed * by each process' filter, and if accepted, stashed into the corresponding * buffer. */ void bpf_tap(struct ifnet *ifp, u_char *pkt, u_int pktlen) { struct bpf_if *bp; register struct bpf_d *d; register u_int slen; /* * Note that the ipl does not have to be raised at this point. * The only problem that could arise here is that if two different * interfaces shared any data. This is not the case. */ lck_mtx_lock(bpf_mlock); bp = ifp->if_bpf; #ifdef __APPLE__ if (bp) { #endif for (d = bp->bif_dlist; d != 0; d = d->bd_next) { ++d->bd_rcount; slen = bpf_filter(d->bd_filter, pkt, pktlen, pktlen); if (slen != 0) catchpacket(d, pkt, pktlen, slen, bcopy); } #ifdef __APPLE__ } lck_mtx_unlock(bpf_mlock); #endif } /* * Copy data from an mbuf chain into a buffer. This code is derived * from m_copydata in sys/uipc_mbuf.c. */ static void bpf_mcopy(const void *src_arg, void *dst_arg, size_t len) { const struct mbuf *m; u_int count; u_char *dst; m = src_arg; dst = dst_arg; while (len > 0) { if (m == 0) panic("bpf_mcopy"); count = min(m->m_len, len); bcopy(mtod(m, const void *), dst, count); m = m->m_next; dst += count; len -= count; } } /* * Incoming linkage from device drivers, when packet is in an mbuf chain. */ void bpf_mtap(struct ifnet *ifp, struct mbuf *m) { struct bpf_if *bp; struct bpf_d *d; u_int pktlen, slen; struct mbuf *m0; lck_mtx_lock(bpf_mlock); bp = ifp->if_bpf; if (bp) { pktlen = 0; for (m0 = m; m0 != 0; m0 = m0->m_next) pktlen += m0->m_len; for (d = bp->bif_dlist; d != 0; d = d->bd_next) { if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL)) continue; ++d->bd_rcount; slen = bpf_filter(d->bd_filter, (u_char *)m, pktlen, 0); if (slen != 0) catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy); } } lck_mtx_unlock(bpf_mlock); } /* * Move the packet data from interface memory (pkt) into the * store buffer. Return 1 if it's time to wakeup a listener (buffer full), * otherwise 0. "copy" is the routine called to do the actual data * transfer. bcopy is passed in to copy contiguous chunks, while * bpf_mcopy is passed in to copy mbuf chains. In the latter case, * pkt is really an mbuf. */ static void catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, void (*cpfn)(const void *, void *, size_t)) { register struct bpf_hdr *hp; register int totlen, curlen; register int hdrlen = d->bd_bif->bif_hdrlen; /* * Figure out how many bytes to move. If the packet is * greater or equal to the snapshot length, transfer that * much. Otherwise, transfer the whole packet (unless * we hit the buffer size limit). */ totlen = hdrlen + min(snaplen, pktlen); if (totlen > d->bd_bufsize) totlen = d->bd_bufsize; /* * Round up the end of the previous packet to the next longword. */ curlen = BPF_WORDALIGN(d->bd_slen); if (curlen + totlen > d->bd_bufsize) { /* * This packet will overflow the storage buffer. * Rotate the buffers if we can, then wakeup any * pending reads. */ if (d->bd_fbuf == 0) { /* * We haven't completed the previous read yet, * so drop the packet. */ ++d->bd_dcount; return; } ROTATE_BUFFERS(d); bpf_wakeup(d); curlen = 0; } else if (d->bd_immediate) /* * Immediate mode is set. A packet arrived so any * reads should be woken up. */ bpf_wakeup(d); /* * Append the bpf header. */ hp = (struct bpf_hdr *)(d->bd_sbuf + curlen); #if BSD >= 199103 microtime(&hp->bh_tstamp); #elif defined(sun) uniqtime(&hp->bh_tstamp); #else hp->bh_tstamp = time; #endif hp->bh_datalen = pktlen; hp->bh_hdrlen = hdrlen; /* * Copy the packet data into the store buffer and update its length. */ (*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen)); d->bd_slen = curlen + totlen; } /* * Initialize all nonzero fields of a descriptor. */ static int bpf_allocbufs(struct bpf_d *d) { d->bd_fbuf = (caddr_t) _MALLOC(d->bd_bufsize, M_DEVBUF, M_WAIT); if (d->bd_fbuf == 0) return (ENOBUFS); d->bd_sbuf = (caddr_t) _MALLOC(d->bd_bufsize, M_DEVBUF, M_WAIT); if (d->bd_sbuf == 0) { FREE(d->bd_fbuf, M_DEVBUF); return (ENOBUFS); } d->bd_slen = 0; d->bd_hlen = 0; return (0); } /* * Free buffers currently in use by a descriptor. * Called on close. */ static void bpf_freed(struct bpf_d *d) { /* * We don't need to lock out interrupts since this descriptor has * been detached from its interface and it yet hasn't been marked * free. */ if (d->bd_sbuf != 0) { FREE(d->bd_sbuf, M_DEVBUF); if (d->bd_hbuf != 0) FREE(d->bd_hbuf, M_DEVBUF); if (d->bd_fbuf != 0) FREE(d->bd_fbuf, M_DEVBUF); } if (d->bd_filter) FREE((caddr_t)d->bd_filter, M_DEVBUF); } /* * Attach an interface to bpf. driverp is a pointer to a (struct bpf_if *) * in the driver's softc; dlt is the link layer type; hdrlen is the fixed * size of the link header (variable length headers not yet supported). */ void bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) { struct bpf_if *bp; bp = (struct bpf_if *) _MALLOC(sizeof(*bp), M_DEVBUF, M_WAIT); if (bp == 0) panic("bpfattach"); lck_mtx_lock(bpf_mlock); bp->bif_dlist = 0; bp->bif_ifp = ifp; bp->bif_dlt = dlt; bp->bif_next = bpf_iflist; bpf_iflist = bp; bp->bif_ifp->if_bpf = 0; /* * Compute the length of the bpf header. This is not necessarily * equal to SIZEOF_BPF_HDR because we want to insert spacing such * that the network layer header begins on a longword boundary (for * performance reasons and to alleviate alignment restrictions). */ bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen; /* Take a reference on the interface */ ifp_reference(ifp); lck_mtx_unlock(bpf_mlock); #ifndef __APPLE__ if (bootverbose) printf("bpf: %s%d attached\n", ifp->if_name, ifp->if_unit); #endif } /* * Detach bpf from an interface. This involves detaching each descriptor * associated with the interface, and leaving bd_bif NULL. Notify each * descriptor as it's detached so that any sleepers wake up and get * ENXIO. */ void bpfdetach(struct ifnet *ifp) { struct bpf_if *bp, *bp_prev; struct bpf_d *d; int s; s = splimp(); lck_mtx_lock(bpf_mlock); /* Locate BPF interface information */ bp_prev = NULL; for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { if (ifp == bp->bif_ifp) break; bp_prev = bp; } #ifdef __APPLE__ /* Check for no BPF interface information */ if (bp == NULL) { return; } #endif /* Interface wasn't attached */ if (bp->bif_ifp == NULL) { splx(s); #ifndef __APPLE__ printf("bpfdetach: %s%d was not attached\n", ifp->if_name, ifp->if_unit); #endif return; } while ((d = bp->bif_dlist) != NULL) { bpf_detachd(d); bpf_wakeup(d); } if (bp_prev) { bp_prev->bif_next = bp->bif_next; } else { bpf_iflist = bp->bif_next; } ifp_release(ifp); lck_mtx_unlock(bpf_mlock); FREE(bp, M_DEVBUF); splx(s); } void bpf_init(__unused void *unused) { #ifdef __APPLE__ int i; int maj; if (bpf_devsw_installed == 0) { bpf_devsw_installed = 1; bpf_mlock_grp_attr = lck_grp_attr_alloc_init(); lck_grp_attr_setdefault(bpf_mlock_grp_attr); bpf_mlock_grp = lck_grp_alloc_init("bpf", bpf_mlock_grp_attr); bpf_mlock_attr = lck_attr_alloc_init(); lck_attr_setdefault(bpf_mlock_attr); bpf_mlock = lck_mtx_alloc_init(bpf_mlock_grp, bpf_mlock_attr); if (bpf_mlock == 0) { printf("bpf_init: failed to allocate bpf_mlock\n"); bpf_devsw_installed = 0; return; } maj = cdevsw_add(CDEV_MAJOR, &bpf_cdevsw); if (maj == -1) { if (bpf_mlock) lck_mtx_free(bpf_mlock, bpf_mlock_grp); if (bpf_mlock_attr) lck_attr_free(bpf_mlock_attr); if (bpf_mlock_grp) lck_grp_free(bpf_mlock_grp); if (bpf_mlock_grp_attr) lck_grp_attr_free(bpf_mlock_grp_attr); bpf_mlock = 0; bpf_mlock_attr = 0; bpf_mlock_grp = 0; bpf_mlock_grp_attr = 0; bpf_devsw_installed = 0; printf("bpf_init: failed to allocate a major number!\n"); return; } for (i = 0 ; i < NBPFILTER; i++) bpf_make_dev_t(maj); } #else cdevsw_add(&bpf_cdevsw); #endif } #ifndef __APPLE__ SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvinit,NULL) #endif #else /* !BPF */ #ifndef __APPLE__ /* * NOP stubs to allow bpf-using drivers to load and function. * * A 'better' implementation would allow the core bpf functionality * to be loaded at runtime. */ void bpf_tap(ifp, pkt, pktlen) struct ifnet *ifp; register u_char *pkt; register u_int pktlen; { } void bpf_mtap(ifp, m) struct ifnet *ifp; struct mbuf *m; { } void bpfattach(ifp, dlt, hdrlen) struct ifnet *ifp; u_int dlt, hdrlen; { } void bpfdetach(ifp) struct ifnet *ifp; { } u_int bpf_filter(pc, p, wirelen, buflen) register const struct bpf_insn *pc; register u_char *p; u_int wirelen; register u_int buflen; { return -1; /* "no filter" behaviour */ } #endif /* !defined(__APPLE__) */ #endif /* NBPFILTER > 0 */