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/***********************************************************************
*
* pppoe.h
*
* Declaration of various PPPoE constants
*
* Copyright (C) 2000 Roaring Penguin Software Inc.
*
* This program may be distributed according to the terms of the GNU
* General Public License, version 2 or (at your option) any later version.
*
* $Id$
*
***********************************************************************/
#ifdef __sun__
#define __EXTENSIONS__
#endif
#include "config.h"
#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H)
#define _POSIX_SOURCE 1 /* For sigaction defines */
#endif
#include <stdio.h> /* For FILE */
#include <sys/types.h> /* For pid_t */
/* How do we access raw Ethernet devices? */
#undef USE_LINUX_PACKET
#undef USE_BPF
#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H)
#define USE_LINUX_PACKET 1
#elif defined(HAVE_NET_BPF_H)
#define USE_BPF 1
#elif defined(HAVE_SYS_DLPI_H)
#define USE_DLPI
#endif
/* Sanity check */
#if !defined(USE_BPF) && !defined(USE_LINUX_PACKET) && !defined(USE_DLPI)
#error Unknown method for accessing raw Ethernet frames
#endif
#ifdef HAVE_SYS_CDEFS_H
#include <sys/cdefs.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
/* Ugly header files on some Linux boxes... */
#if defined(HAVE_LINUX_IF_H)
#include <linux/if.h>
#elif defined(HAVE_NET_IF_H)
#include <net/if.h>
#endif
#ifdef HAVE_NET_IF_TYPES_H
#include <net/if_types.h>
#endif
#ifdef HAVE_NET_IF_DL_H
#include <net/if_dl.h>
#endif
/* I'm not sure why this is needed... I do not have OpenBSD */
#if defined(__OpenBSD__)
#include <net/ppp_defs.h>
#include <net/if_ppp.h>
#endif
#ifdef USE_BPF
extern int bpfSize;
struct PPPoEPacketStruct;
void sessionDiscoveryPacket(struct PPPoEPacketStruct *packet);
#define BPF_BUFFER_IS_EMPTY (bpfSize <= 0)
#define BPF_BUFFER_HAS_DATA (bpfSize > 0)
#define ethhdr ether_header
#define h_dest ether_dhost
#define h_source ether_shost
#define h_proto ether_type
#define ETH_DATA_LEN ETHERMTU
#define ETH_ALEN ETHER_ADDR_LEN
#else
#undef USE_BPF
#define BPF_BUFFER_IS_EMPTY 1
#define BPF_BUFFER_HAS_DATA 0
#endif
#ifdef USE_DLPI
#include <sys/ethernet.h>
#define ethhdr ether_header
#define ETH_DATA_LEN ETHERMTU
#define ETH_ALEN ETHERADDRL
#define h_dest ether_dhost.ether_addr_octet
#define h_source ether_shost.ether_addr_octet
#define h_proto ether_type
/* cloned from dltest.h */
#define MAXDLBUF 8192
#define MAXDLADDR 1024
#define MAXWAIT 15
#define OFFADDR(s, n) (u_char*)((char*)(s) + (int)(n))
#define CASERET(s) case s: return ("s")
#endif
/* Define various integer types -- assumes a char is 8 bits */
#if SIZEOF_UNSIGNED_SHORT == 2
typedef unsigned short UINT16_t;
#elif SIZEOF_UNSIGNED_INT == 2
typedef unsigned int UINT16_t;
#else
#error Could not find a 16-bit integer type
#endif
#if SIZEOF_UNSIGNED_SHORT == 4
typedef unsigned short UINT32_t;
#elif SIZEOF_UNSIGNED_INT == 4
typedef unsigned int UINT32_t;
#elif SIZEOF_UNSIGNED_LONG == 4
typedef unsigned long UINT32_t;
#else
#error Could not find a 16-bit integer type
#endif
#ifdef HAVE_LINUX_IF_ETHER_H
#include <linux/if_ether.h>
#endif
#include <netinet/in.h>
#ifdef HAVE_NETINET_IF_ETHER_H
#include <sys/types.h>
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifndef HAVE_SYS_DLPI_H
#include <netinet/if_ether.h>
#endif
#endif
/* Ethernet frame types according to RFC 2516 */
#define ETH_PPPOE_DISCOVERY 0x8863
#define ETH_PPPOE_SESSION 0x8864
/* But some brain-dead peers disobey the RFC, so frame types are variables */
extern UINT16_t Eth_PPPOE_Discovery;
extern UINT16_t Eth_PPPOE_Session;
/* PPPoE codes */
#define CODE_PADI 0x09
#define CODE_PADO 0x07
#define CODE_PADR 0x19
#define CODE_PADS 0x65
#define CODE_PADT 0xA7
#define CODE_SESS 0x00
/* PPPoE Tags */
#define TAG_END_OF_LIST 0x0000
#define TAG_SERVICE_NAME 0x0101
#define TAG_AC_NAME 0x0102
#define TAG_HOST_UNIQ 0x0103
#define TAG_AC_COOKIE 0x0104
#define TAG_VENDOR_SPECIFIC 0x0105
#define TAG_RELAY_SESSION_ID 0x0110
#define TAG_SERVICE_NAME_ERROR 0x0201
#define TAG_AC_SYSTEM_ERROR 0x0202
#define TAG_GENERIC_ERROR 0x0203
/* Discovery phase states */
#define STATE_SENT_PADI 0
#define STATE_RECEIVED_PADO 1
#define STATE_SENT_PADR 2
#define STATE_SESSION 3
#define STATE_TERMINATED 4
/* How many PADI/PADS attempts? */
#define MAX_PADI_ATTEMPTS 3
/* Initial timeout for PADO/PADS */
#define PADI_TIMEOUT 5
/* States for scanning PPP frames */
#define STATE_WAITFOR_FRAME_ADDR 0
#define STATE_DROP_PROTO 1
#define STATE_BUILDING_PACKET 2
/* Special PPP frame characters */
#define FRAME_ESC 0x7D
#define FRAME_FLAG 0x7E
#define FRAME_ADDR 0xFF
#define FRAME_CTRL 0x03
#define FRAME_ENC 0x20
#define IPV4ALEN 4
#define SMALLBUF 256
/* A PPPoE Packet, including Ethernet headers */
typedef struct PPPoEPacketStruct {
struct ethhdr ethHdr; /* Ethernet header */
#ifdef PACK_BITFIELDS_REVERSED
unsigned int type:4; /* PPPoE Type (must be 1) */
unsigned int ver:4; /* PPPoE Version (must be 1) */
#else
unsigned int ver:4; /* PPPoE Version (must be 1) */
unsigned int type:4; /* PPPoE Type (must be 1) */
#endif
unsigned int code:8; /* PPPoE code */
unsigned int session:16; /* PPPoE session */
unsigned int length:16; /* Payload length */
unsigned char payload[ETH_DATA_LEN]; /* A bit of room to spare */
} PPPoEPacket;
/* Header size of a PPPoE packet */
#define PPPOE_OVERHEAD 6 /* type, code, session, length */
#define HDR_SIZE (sizeof(struct ethhdr) + PPPOE_OVERHEAD)
#define MAX_PPPOE_PAYLOAD (ETH_DATA_LEN - PPPOE_OVERHEAD)
#define MAX_PPPOE_MTU (MAX_PPPOE_PAYLOAD - 2)
/* PPPoE Tag */
typedef struct PPPoETagStruct {
unsigned int type:16; /* tag type */
unsigned int length:16; /* Length of payload */
unsigned char payload[ETH_DATA_LEN]; /* A LOT of room to spare */
} PPPoETag;
/* Header size of a PPPoE tag */
#define TAG_HDR_SIZE 4
/* Chunk to read from stdin */
#define READ_CHUNK 4096
/* Function passed to parsePacket */
typedef void ParseFunc(UINT16_t type,
UINT16_t len,
unsigned char *data,
void *extra);
/* Structures used by PPPoE server */
struct ClientSession {
pid_t pid; /* PID of child handling session */
unsigned char ip[IPV4ALEN]; /* IP address of peer */
UINT16_t sess; /* Session number */
unsigned char eth[ETH_ALEN]; /* Peer's Ethernet address */
int recvdPADT; /* Peer sent a PADT */
};
#define PPPINITFCS16 0xffff /* Initial FCS value */
/* Keep track of the state of a connection -- collect everything in
one spot */
typedef struct PPPoEConnectionStruct {
int discoveryState; /* Where we are in discovery */
int discoverySocket; /* Raw socket for discovery frames */
int sessionSocket; /* Raw socket for session frames */
unsigned char myEth[ETH_ALEN]; /* My MAC address */
unsigned char peerEth[ETH_ALEN]; /* Peer's MAC address */
UINT16_t session; /* Session ID */
char *ifName; /* Interface name */
char *serviceName; /* Desired service name, if any */
char *acName; /* Desired AC name, if any */
int synchronous; /* Use synchronous PPP */
int useHostUniq; /* Use Host-Uniq tag */
int printACNames; /* Just print AC names */
int skipDiscovery; /* Skip discovery */
int noDiscoverySocket; /* Don't even open discovery socket */
int killSession; /* Kill session and exit */
FILE *debugFile; /* Debug file for dumping packets */
int numPADOs; /* Number of PADO packets received */
PPPoETag cookie; /* We have to send this if we get it */
PPPoETag relayId; /* Ditto */
} PPPoEConnection;
/* Structure used to determine acceptable PADO or PADS packet */
struct PacketCriteria {
PPPoEConnection *conn;
int acNameOK;
int serviceNameOK;
};
/* Function Prototypes */
UINT16_t etherType(PPPoEPacket *packet);
int openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr);
int sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size);
int receivePacket(int sock, PPPoEPacket *pkt, int *size);
void fatalSys(char const *str);
void rp_fatal(char const *str);
void printErr(char const *str);
void sysErr(char const *str);
void dumpPacket(FILE *fp, PPPoEPacket *packet, char const *dir);
void dumpHex(FILE *fp, unsigned char const *buf, int len);
int parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra);
void parseLogErrs(UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra);
void syncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet);
void asyncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet);
void asyncReadFromEth(PPPoEConnection *conn, int sock, int clampMss);
void syncReadFromEth(PPPoEConnection *conn, int sock, int clampMss);
char *strDup(char const *str);
void sendPADT(PPPoEConnection *conn, char const *msg);
void sendSessionPacket(PPPoEConnection *conn,
PPPoEPacket *packet, int len);
void initPPP(void);
void clampMSS(PPPoEPacket *packet, char const *dir, int clampMss);
UINT16_t computeTCPChecksum(unsigned char *ipHdr, unsigned char *tcpHdr);
UINT16_t pppFCS16(UINT16_t fcs, unsigned char *cp, int len);
void discovery(PPPoEConnection *conn);
unsigned char *findTag(PPPoEPacket *packet, UINT16_t tagType,
PPPoETag *tag);
#define SET_STRING(var, val) do { if (var) free(var); var = strDup(val); } while(0);
#define CHECK_ROOM(cursor, start, len) \
do {\
if (((cursor)-(start))+(len) > MAX_PPPOE_PAYLOAD) { \
syslog(LOG_ERR, "Would create too-long packet"); \
return; \
} \
} while(0)
/* True if Ethernet address is broadcast or multicast */
#define NOT_UNICAST(e) ((e[0] & 0x01) != 0)
#define BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) == 0xFF)
#define NOT_BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) != 0xFF)
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