pcap-libdlpi.c

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/*
 * 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.
 */
 
#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 *, int);
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) pcap_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->priv;
    int status = 0;
    int retv;
    dlpi_handle_t dh;
    dlpi_info_t dlinfo;
 
    /*
     * 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.device, &dh, DLPI_RAW|DLPI_PASSIVE);
    if (retv != DLPI_SUCCESS) {
        if (retv == DLPI_ELINKNAMEINVAL || retv == DLPI_ENOLINK)
            status = PCAP_ERROR_NO_SUCH_DEVICE;
        else if (retv == DL_SYSERR &&
            (errno == EPERM || errno == EACCES))
            status = PCAP_ERROR_PERM_DENIED;
        else
            status = PCAP_ERROR;
        pcap_libdlpi_err(p->opt.device, "dlpi_open", retv,
            p->errbuf);
        return (status);
    }
    pd->dlpi_hd = dh;
 
    if (p->opt.rfmon) {
        /*
         * This device exists, but we don't support monitor mode
         * any platforms that support DLPI.
         */
        status = PCAP_ERROR_RFMON_NOTSUP;
        goto bad;
    }
 
    /* Bind with DLPI_ANY_SAP. */
    if ((retv = dlpi_bind(pd->dlpi_hd, DLPI_ANY_SAP, 0)) != DLPI_SUCCESS) {
        status = PCAP_ERROR;
        pcap_libdlpi_err(p->opt.device, "dlpi_bind", retv, p->errbuf);
        goto bad;
    }
 
    /*
     * Turn a negative snapshot value (invalid), a snapshot value of
     * 0 (unspecified), or a value bigger than the normal maximum
     * value, into the maximum allowed value.
     *
     * If some application really *needs* a bigger snapshot
     * length, we should just increase MAXIMUM_SNAPLEN.
     */
    if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
        p->snapshot = MAXIMUM_SNAPLEN;
 
    /* Enable promiscuous mode. */
    if (p->opt.promisc) {
        retv = dlpromiscon(p, DL_PROMISC_PHYS);
        if (retv < 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 (retv == PCAP_ERROR_PERM_DENIED)
                status = PCAP_ERROR_PROMISC_PERM_DENIED;
            else
                status = retv;
            goto bad;
        }
    } else {
        /* Try to enable multicast. */
        retv = dlpromiscon(p, DL_PROMISC_MULTI);
        if (retv < 0) {
            status = retv;
            goto bad;
        }
    }
 
    /* Try to enable SAP promiscuity. */
    retv = dlpromiscon(p, DL_PROMISC_SAP);
    if (retv < 0) {
        /*
         * Not fatal, since the DL_PROMISC_PHYS mode worked.
         * Report it as a warning, however.
         */
        if (p->opt.promisc)
            status = PCAP_WARNING;
        else {
            status = retv;
            goto bad;
        }
    }
 
    /* Determine link type.  */
    if ((retv = dlpi_info(pd->dlpi_hd, &dlinfo, 0)) != DLPI_SUCCESS) {
        status = PCAP_ERROR;
        pcap_libdlpi_err(p->opt.device, "dlpi_info", retv, p->errbuf);
        goto bad;
    }
 
    if (pcap_process_mactype(p, dlinfo.di_mactype) != 0) {
        status = PCAP_ERROR;
        goto bad;
    }
 
    p->fd = dlpi_fd(pd->dlpi_hd);
 
    /* Push and configure bufmod. */
    if (pcap_conf_bufmod(p, p->snapshot) != 0) {
        status = PCAP_ERROR;
        goto bad;
    }
 
    /*
     * Flush the read side.
     */
    if (ioctl(p->fd, I_FLUSH, FLUSHR) != 0) {
        status = PCAP_ERROR;
        pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
            errno, "FLUSHR");
        goto bad;
    }
 
    /* Allocate data buffer. */
    if (pcap_alloc_databuf(p) != 0) {
        status = PCAP_ERROR;
        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 (status);
bad:
    pcap_cleanup_libdlpi(p);
    return (status);
}
 
#define STRINGIFY(n)    #n
 
static int
dlpromiscon(pcap_t *p, bpf_u_int32 level)
{
    struct pcap_dlpi *pd = p->priv;
    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.device, "dlpi_promiscon" STRINGIFY(level),
            retv, p->errbuf);
        return (err);
    }
    return (0);
}
 
/*
 * Presumably everything returned by dlpi_walk() is a DLPI device,
 * so there's no work to be done here to check whether name refers
 * to a DLPI device.
 */
static int
is_dlpi_interface(const char *name _U_)
{
    return (1);
}
 
static int
get_if_flags(const char *name _U_, bpf_u_int32 *flags _U_, char *errbuf _U_)
{
    /*
     * Nothing we can do other than mark loopback devices as "the
     * connected/disconnected status doesn't apply".
     *
     * XXX - on Solaris, can we do what the dladm command does,
     * i.e. get a connected/disconnected indication from a kstat?
     * (Note that you can also get the link speed, and possibly
     * other information, from a kstat as well.)
     */
    if (*flags & PCAP_IF_LOOPBACK) {
        /*
         * Loopback devices aren't wireless, and "connected"/
         * "disconnected" doesn't apply to them.
         */
        *flags |= PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE;
        return (0);
    }
    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_list_t *devlistp, char *errbuf)
{
    int retv = 0;
 
    linknamelist_t  *entry, *next;
    linkwalk_t  lw = {NULL, 0};
    int         save_errno;
 
    /*
     * Get the list of regular interfaces first.
     */
    if (pcap_findalldevs_interfaces(devlistp, errbuf,
        is_dlpi_interface, get_if_flags) == -1)
        return (-1);    /* failure */
 
    /* dlpi_walk() for loopback will be added here. */
 
    /*
     * Find all DLPI devices in the current zone.
     *
     * XXX - will pcap_findalldevs_interfaces() find any devices
     * outside the current zone?  If not, the only reason to call
     * it would be to get the interface addresses.
     */
    dlpi_walk(list_interfaces, &lw, 0);
 
    if (lw.lw_err != 0) {
        pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
            lw.lw_err, "dlpi_walk");
        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 it isn't already in the list of devices, try to
         * add it.
         */
        if (find_or_add_dev(devlistp, entry->linkname, 0, get_if_flags,
            NULL, errbuf) == NULL)
            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->priv;
    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 = (u_char *)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, int size)
{
    struct pcap_dlpi *pd = p->priv;
    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->priv;
 
    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 _U_, char *ebuf)
{
    pcap_t *p;
 
    p = PCAP_CREATE_COMMON(ebuf, struct pcap_dlpi);
    if (p == NULL)
        return (NULL);
 
    p->activate_op = pcap_activate_libdlpi;
    return (p);
}
 
/*
 * Libpcap version string.
 */
const char *
pcap_lib_version(void)
{
    return (PCAP_VERSION_STRING);
}