[libpcap] / pcap-libdlpi.c

/*
 * Copyright (c) 1993, 1994, 1995, 1996, 1997
 *      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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * This code contributed by Sagun Shakya (sagun.shakya@sun.com)
 */
/*
 * Packet capture routines for DLPI using libdlpi under SunOS 5.11.
 */

#ifndef lint
static const char rcsid[] _U_ =
        "@(#) $Header: /tcpdump/master/libpcap/pcap-libdlpi.c,v 1.6 2008-04-14 20:40:58 guy Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>
#include <sys/time.h>
#include <sys/bufmod.h>
#include <sys/stream.h>
#include <libdlpi.h>
#include <errno.h>
#include <memory.h>
#include <stropts.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "pcap-int.h"
#include "dlpisubs.h"

/* Forwards. */
static int dlpromiscon(pcap_t *, bpf_u_int32);
static int pcap_read_libdlpi(pcap_t *, int, pcap_handler, u_char *);
static int pcap_inject_libdlpi(pcap_t *, const void *, size_t);
static void pcap_libdlpi_err(const char *, const char *, int, char *);
static void pcap_cleanup_libdlpi(pcap_t *);

/*
 * list_interfaces() will list all the network links that are
 * available on a system.
 */
static boolean_t list_interfaces(const char *, void *);

typedef struct linknamelist {
        char    linkname[DLPI_LINKNAME_MAX];
        struct linknamelist *lnl_next;
} linknamelist_t;

typedef struct linkwalk {
        linknamelist_t  *lw_list;
        int             lw_err;
} linkwalk_t;

/*
 * The caller of this function should free the memory allocated
 * for each linknamelist_t "entry" allocated.
 */
static boolean_t
list_interfaces(const char *linkname, void *arg)
{
        linkwalk_t      *lwp = arg;
        linknamelist_t  *entry;

        if ((entry = calloc(1, sizeof(linknamelist_t))) == NULL) {
                lwp->lw_err = ENOMEM;
                return (B_TRUE);
        }
        (void) strlcpy(entry->linkname, linkname, DLPI_LINKNAME_MAX);

        if (lwp->lw_list == NULL) {
                lwp->lw_list = entry;
        } else {
                entry->lnl_next = lwp->lw_list;
                lwp->lw_list = entry;
        }

        return (B_FALSE);
}

static int
pcap_activate_libdlpi(pcap_t *p)
{
        struct pcap_dlpi *pd = p->private;
        int retv;
        dlpi_handle_t dh;
        dlpi_info_t dlinfo;
        int err = PCAP_ERROR;

        /*
         * Enable Solaris raw and passive DLPI extensions;
         * dlpi_open() will not fail if the underlying link does not support
         * passive mode. See dlpi(7P) for details.
         */
        retv = dlpi_open(p->opt.source, &dh, DLPI_RAW|DLPI_PASSIVE);
        if (retv != DLPI_SUCCESS) {
                if (retv == DLPI_ELINKNAMEINVAL || retv == DLPI_ENOLINK)
                        err = PCAP_ERROR_NO_SUCH_DEVICE;
                else if (retv == DL_SYSERR &&
                    (errno == EPERM || errno == EACCES))
                        err = PCAP_ERROR_PERM_DENIED;
                pcap_libdlpi_err(p->opt.source, "dlpi_open", retv,
                    p->errbuf);
                return (err);
        }
        pd->dlpi_hd = dh;

        if (p->opt.rfmon) {
                /*
                 * This device exists, but we don't support monitor mode
                 * any platforms that support DLPI.
                 */
                err = PCAP_ERROR_RFMON_NOTSUP;
                goto bad;
        }

        /* Bind with DLPI_ANY_SAP. */
        if ((retv = dlpi_bind(pd->dlpi_hd, DLPI_ANY_SAP, 0)) != DLPI_SUCCESS) {
                pcap_libdlpi_err(p->opt.source, "dlpi_bind", retv, p->errbuf);
                goto bad;
        }

        /* Enable promiscuous mode. */
        if (p->opt.promisc) {
                err = dlpromiscon(p, DL_PROMISC_PHYS);
                if (err < 0) {
                        /*
                         * "You don't have permission to capture on
                         * this device" and "you don't have permission
                         * to capture in promiscuous mode on this
                         * device" are different; let the user know,
                         * so if they can't get permission to
                         * capture in promiscuous mode, they can at
                         * least try to capture in non-promiscuous
                         * mode.
                         *
                         * XXX - you might have to capture in
                         * promiscuous mode to see outgoing packets.
                         */
                        if (err == PCAP_ERROR_PERM_DENIED)
                                err = PCAP_ERROR_PROMISC_PERM_DENIED;
                        goto bad;
                }
        } else {
                /* Try to enable multicast. */
                err = dlpromiscon(p, DL_PROMISC_MULTI);
                if (err < 0)
                        goto bad;
        }

        /* Try to enable SAP promiscuity. */
        err = dlpromiscon(p, DL_PROMISC_SAP);
        if (err < 0) {
                /*
                 * Not fatal, since the DL_PROMISC_PHYS mode worked.
                 * Report it as a warning, however.
                 */
                if (p->opt.promisc)
                        err = PCAP_WARNING;
                else
                        goto bad;
        }

        /* Determine link type.  */
        if ((retv = dlpi_info(pd->dlpi_hd, &dlinfo, 0)) != DLPI_SUCCESS) {
                pcap_libdlpi_err(p->opt.source, "dlpi_info", retv, p->errbuf);
                goto bad;
        }

        if (pcap_process_mactype(p, dlinfo.di_mactype) != 0)
                goto bad;

        p->fd = dlpi_fd(pd->dlpi_hd);

        /* Push and configure bufmod. */
        if (pcap_conf_bufmod(p, p->snapshot) != 0)
                goto bad;

        /*
         * Flush the read side.
         */
        if (ioctl(p->fd, I_FLUSH, FLUSHR) != 0) {
                snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "FLUSHR: %s",
                    pcap_strerror(errno));
                goto bad;
        }

        /* Allocate data buffer. */
        if (pcap_alloc_databuf(p) != 0)
                goto bad;

        /*
         * "p->fd" is a FD for a STREAMS device, so "select()" and
         * "poll()" should work on it.
         */
        p->selectable_fd = p->fd;

        p->read_op = pcap_read_libdlpi;
        p->inject_op = pcap_inject_libdlpi;
        p->setfilter_op = install_bpf_program;  /* No kernel filtering */
        p->setdirection_op = NULL;      /* Not implemented */
        p->set_datalink_op = NULL;      /* Can't change data link type */
        p->getnonblock_op = pcap_getnonblock_fd;
        p->setnonblock_op = pcap_setnonblock_fd;
        p->stats_op = pcap_stats_dlpi;
        p->cleanup_op = pcap_cleanup_libdlpi;

        return (0);
bad:
        pcap_cleanup_libdlpi(p);
        return (err);
}

#define STRINGIFY(n)    #n

static int
dlpromiscon(pcap_t *p, bpf_u_int32 level)
{
        struct pcap_dlpi *pd = p->private;
        int retv;
        int err;

        retv = dlpi_promiscon(pd->dlpi_hd, level);
        if (retv != DLPI_SUCCESS) {
                if (retv == DL_SYSERR &&
                    (errno == EPERM || errno == EACCES))
                        err = PCAP_ERROR_PERM_DENIED;
                else
                        err = PCAP_ERROR;
                pcap_libdlpi_err(p->opt.source, "dlpi_promiscon" STRINGIFY(level),
                    retv, p->errbuf);
                return (err);
        }
        return (0);
}

/*
 * In Solaris, the "standard" mechanism" i.e SIOCGLIFCONF will only find
 * network links that are plumbed and are up. dlpi_walk(3DLPI) will find
 * additional network links present in the system.
 */
int
pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
{
        int retv = 0;

        linknamelist_t  *entry, *next;
        linkwalk_t      lw = {NULL, 0};
        int             save_errno;

        /* dlpi_walk() for loopback will be added here. */

        dlpi_walk(list_interfaces, &lw, 0);

        if (lw.lw_err != 0) {
                snprintf(errbuf, PCAP_ERRBUF_SIZE,
                    "dlpi_walk: %s", pcap_strerror(lw.lw_err));
                retv = -1;
                goto done;
        }

        /* Add linkname if it does not exist on the list. */
        for (entry = lw.lw_list; entry != NULL; entry = entry->lnl_next) {
                if (pcap_add_if(alldevsp, entry->linkname, 0, NULL, errbuf) < 0)
                        retv = -1;
        }
done:
        save_errno = errno;
        for (entry = lw.lw_list; entry != NULL; entry = next) {
                next = entry->lnl_next;
                free(entry);
        }
        errno = save_errno;

        return (retv);
}

/*
 * Read data received on DLPI handle. Returns -2 if told to terminate, else
 * returns the number of packets read.
 */
static int
pcap_read_libdlpi(pcap_t *p, int count, pcap_handler callback, u_char *user)
{
        struct pcap_dlpi *pd = p->private;
        int len;
        u_char *bufp;
        size_t msglen;
        int retv;

        len = p->cc;
        if (len != 0) {
                bufp = p->bp;
                goto process_pkts;
        }
        do {
                /* Has "pcap_breakloop()" been called? */
                if (p->break_loop) {
                        /*
                         * Yes - clear the flag that indicates that it has,
                         * and return -2 to indicate that we were told to
                         * break out of the loop.
                         */
                        p->break_loop = 0;
                        return (-2);
                }

                msglen = p->bufsize;
                bufp = p->buffer + p->offset;

                retv = dlpi_recv(pd->dlpi_hd, NULL, NULL, bufp,
                    &msglen, -1, NULL);
                if (retv != DLPI_SUCCESS) {
                        /*
                         * This is most likely a call to terminate out of the
                         * loop. So, do not return an error message, instead
                         * check if "pcap_breakloop()" has been called above.
                         */
                        if (retv == DL_SYSERR && errno == EINTR) {
                                len = 0;
                                continue;
                        }
                        pcap_libdlpi_err(dlpi_linkname(pd->dlpi_hd),
                            "dlpi_recv", retv, p->errbuf);
                        return (-1);
                }
                len = msglen;
        } while (len == 0);

process_pkts:
        return (pcap_process_pkts(p, callback, user, count, bufp, len));
}

static int
pcap_inject_libdlpi(pcap_t *p, const void *buf, size_t size)
{
        struct pcap_dlpi *pd = p->private;
        int retv;

        retv = dlpi_send(pd->dlpi_hd, NULL, 0, buf, size, NULL);
        if (retv != DLPI_SUCCESS) {
                pcap_libdlpi_err(dlpi_linkname(pd->dlpi_hd), "dlpi_send", retv,
                    p->errbuf);
                return (-1);
        }
        /*
         * dlpi_send(3DLPI) does not provide a way to return the number of
         * bytes sent on the wire. Based on the fact that DLPI_SUCCESS was
         * returned we are assuming 'size' bytes were sent.
         */
        return (size);
}

/*
 * Close dlpi handle.
 */
static void
pcap_cleanup_libdlpi(pcap_t *p)
{
        struct pcap_dlpi *pd = p->private;

        if (pd->dlpi_hd != NULL) {
                dlpi_close(pd->dlpi_hd);
                pd->dlpi_hd = NULL;
                p->fd = -1;
        }
        pcap_cleanup_live_common(p);
}

/*
 * Write error message to buffer.
 */
static void
pcap_libdlpi_err(const char *linkname, const char *func, int err, char *errbuf)
{
        snprintf(errbuf, PCAP_ERRBUF_SIZE, "libpcap: %s failed on %s: %s",
            func, linkname, dlpi_strerror(err));
}

pcap_t *
pcap_create_interface(const char *device, char *ebuf)
{
        pcap_t *p;

        p = pcap_create_common(device, ebuf, sizeof (struct pcap_dlpi));
        if (p == NULL)
                return (NULL);

        p->activate_op = pcap_activate_libdlpi;
        return (p);
}