pcap.h

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#pragma once
/*
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
#ifdef HAVE_LIBPCAP
/** Prototypes and constants for PCAP functions
 *
 * @file src/lib/util/pcap.h
 *
 * @author Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 * @copyright 2013 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 */
RCSIDH(pcap_h, "$Id: a6333f5f7983f2b88bfe05812748c14601feff75 $")
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include "pcap.h"
 
#include <freeradius-devel/build.h>
#include <freeradius-devel/missing.h>
#include <freeradius-devel/util/net.h>
 
#include <pcap.h>
#include <stdbool.h>
#include <sys/types.h>
 
#define SNAPLEN ETHER_HDR_LEN + IP_HDR_LEN + sizeof(udp_header_t) + MAX_RADIUS_LEN
#define PCAP_BUFFER_DEFAULT (10000)
/*
 *      It's unclear why this differs between platforms
 */
#ifndef __linux__
#  define PCAP_NONBLOCK_TIMEOUT (0)
#else
#  define PCAP_NONBLOCK_TIMEOUT (-1)
#endif
 
#ifndef BIOCIMMEDIATE
#  define BIOCIMMEDIATE (2147762800)
#endif
 
/*
 *      Older versions of libpcap don't define this
 */
#ifndef PCAP_NETMASK_UNKNOWN
#  define PCAP_NETMASK_UNKNOWN 0
#endif
 
typedef enum {
        PCAP_INVALID = 0,
        PCAP_INTERFACE_IN,
        PCAP_FILE_IN,
        PCAP_STDIO_IN,
        PCAP_INTERFACE_OUT,
        PCAP_FILE_OUT,
        PCAP_STDIO_OUT,
        PCAP_INTERFACE_IN_OUT
} fr_pcap_type_t;
 
/*
 *      Internal pcap structures
 */
typedef struct fr_pcap fr_pcap_t;
struct fr_pcap {
        char                    errbuf[PCAP_ERRBUF_SIZE];       //!< Last error on this interface.
        fr_pcap_type_t          type;                           //!< What type of handle this is.
        char                    *name;                          //!< Name of file or interface.
        uint8_t                 ether_addr[ETHER_ADDR_LEN];     //!< The MAC address of the interface
        int                     ifindex;                        //!< ifindex of the name we're listening on.
 
        bool                    promiscuous;                    //!< Whether the interface is in promiscuous mode.
                                                                //!< Only valid for live capture handles.
        int                     buffer_pkts;                    //!< How big to make the PCAP ring buffer.
                                                                //!< Actual buffer size is SNAPLEN * buffer.
                                                                //!< Only valid for live capture handles.
 
        pcap_t                  *handle;                        //!< libpcap handle.
        pcap_dumper_t           *dumper;                        //!< libpcap dumper handle.
 
        int                     link_layer;                     //!< Link layer type.
 
        int                     fd;                             //!< Selectable file descriptor we feed to select.
        struct pcap_stat        pstats;                         //!< The last set of pcap stats for this handle.
 
        fr_pcap_t               *next;                          //!< Next handle in collection.
};
 
int             fr_pcap_if_link_layer(pcap_if_t *dev);
fr_pcap_t       *fr_pcap_init(TALLOC_CTX *ctx, char const *name, fr_pcap_type_t type);
int             fr_pcap_open(fr_pcap_t *handle);
int             fr_pcap_apply_filter(fr_pcap_t *handle, char const *expression);
char            *fr_pcap_device_names(TALLOC_CTX *ctx, fr_pcap_t *handle, char c);
int             fr_pcap_mac_addr(uint8_t *macaddr, char *ifname);
bool            fr_pcap_link_layer_supported(int link_layer);
ssize_t         fr_pcap_link_layer_offset(uint8_t const *data, size_t len, int link_layer);
#endif
 
#ifdef __cplusplus
}
#endif