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#ifndef FR_NET_H
#define FR_NET_H
/*
* This program is is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2 of the
* License as published by the Free Software Foundation.
*
* 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
*/
/**
* $Id$
* @file include/net.h
* @brief Structures and functions for parsing raw network packets.
*
* @author Arran Cudbard-Bell <a.cudbardb@freeradius.org>
* @copyright 2014 Arran Cudbard-Bell <a.cudbardb@freeradius.org>
*/
/*
* If we don't have libpcap, we still need an enumeration of link layers.
*/
#ifdef HAVE_LIBPCAP
# include <pcap.h>
#else
typedef enum {
DLT_RAW,
DLT_NULL,
DLT_LOOP,
DLT_EN10MB,
DLT_LINUX_SLL,
DLT_PFLOG
} fr_dlt;
#endif
/*
* The number of bytes in an ethernet (MAC) address.
*/
#define ETHER_ADDR_LEN 6
/*
* Length of a DEC/Intel/Xerox or 802.3 Ethernet header.
* Note that some compilers may pad "struct ether_header" to
* a multiple of 4 *bytes, for example, so "sizeof (struct
* ether_header)" may not give the right answer.
*
* 6 Byte SRC, 6 Byte DST, 2 Byte Ether type, 4 Byte CVID, 4 Byte SVID
*/
#define ETHER_HDR_LEN 22
#define IP_HDR_LEN 60
/*
* The number of bytes in a RADIUS packet header.
*/
#define RADIUS_HDR_LEN 20
/*
* RADIUS packet length.
* RFC 2865, Section 3., subsection 'length' says:
* " ... and maximum length is 4096."
*/
#define MAX_RADIUS_LEN 4096
#define MIN_RADIUS_LEN 20
#define IP_V(ip) (((ip)->ip_vhl & 0xf0) >> 4)
#define IP_HL(ip) ((ip)->ip_vhl & 0x0f)
#define IP_VHL(v, hl) ((v & 0x0f) << 4) | (hl & 0x0f)
#define I_DF 0x4000 //!< Dont fragment flag.
#define IP_MF 0x2000 //!< More fragments flag.
#define IP_OFFMASK 0x1fff //!< Mask for fragmenting bits.
/*
* Structure of a DEC/Intel/Xerox or 802.3 Ethernet header.
*/
typedef struct CC_HINT(__packed__) ethernet_header {
uint8_t ether_dst[ETHER_ADDR_LEN];
uint8_t ether_src[ETHER_ADDR_LEN];
uint16_t ether_type;
} ethernet_header_t;
/*
* Structure of an internet header, naked of options.
*/
typedef struct CC_HINT(__packed__) ip_header {
uint8_t ip_vhl; //!< Header length, version.
uint8_t ip_tos; //!< Type of service.
uint16_t ip_len; //!< Total length.
uint16_t ip_id; //!< identification.
uint16_t ip_off; //!< Fragment offset field.
uint8_t ip_ttl; //!< Time To Live.
uint8_t ip_p; //!< Protocol.
uint16_t ip_sum; //!< Checksum.
struct in_addr ip_src, ip_dst; //!< Src and Dst address
} ip_header_t;
typedef struct CC_HINT(__packed__) ip_header6 {
uint32_t ip_vtcfl; //!< Version, traffic class, flow label.
uint16_t ip_len; //!< Payload length
uint8_t ip_next; //!< Next header (protocol)
uint8_t ip_hopl; //!< IP Hop Limit
struct in6_addr ip_src, ip_dst; //!< Src and Dst address
} ip_header6_t;
/*
* UDP protocol header.
* Per RFC 768, September, 1981.
*/
typedef struct CC_HINT(__packed__) udp_header {
uint16_t src; //!< Source port.
uint16_t dst; //!< Destination port.
uint16_t len; //!< UDP length.
uint16_t checksum; //!< UDP checksum.
} udp_header_t;
typedef struct CC_HINT(__packed__) radius_packet_t {
uint8_t code;
uint8_t id;
uint8_t length[2];
uint8_t vector[AUTH_VECTOR_LEN];
uint8_t data[];
} radius_packet_t;
uint16_t fr_udp_checksum(uint8_t const *data, uint16_t len, uint16_t checksum,
struct in_addr const src_addr, struct in_addr const dst_addr);
uint16_t fr_iph_checksum(uint8_t const *data, uint8_t ihl);
#endif /* FR_NET_H */
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