1/***********************************************************************
2*
3* pppoe.h
4*
5* Declaration of various PPPoE constants
6*
7* Copyright (C) 2000 Roaring Penguin Software Inc.
8*
9* This program may be distributed according to the terms of the GNU
10* General Public License, version 2 or (at your option) any later version.
11*
12* LIC: GPL
13*
14* $Id: pppoe.h,v 1.1.1.1 2008/10/15 03:30:51 james26_jang Exp $
15*
16***********************************************************************/
17
18#include "config.h"
19
20#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H)
21#define _POSIX_SOURCE 1 /* For sigaction defines */
22#endif
23
24#include <stdio.h>		/* For FILE */
25#include <sys/types.h>		/* For pid_t */
26
27/* How do we access raw Ethernet devices? */
28#undef USE_LINUX_PACKET
29#undef USE_BPF
30
31#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H)
32#define USE_LINUX_PACKET 1
33#elif defined(HAVE_SYS_DLPI_H)
34#define USE_DLPI
35#elif defined(HAVE_NET_BPF_H)
36#define USE_BPF 1
37#endif
38
39/* Sanity check */
40#if !defined(USE_BPF) && !defined(USE_LINUX_PACKET) && !defined(USE_DLPI)
41#error Unknown method for accessing raw Ethernet frames
42#endif
43
44#ifdef HAVE_SYS_CDEFS_H
45#include <sys/cdefs.h>
46#endif
47
48#ifdef HAVE_SYS_SOCKET_H
49#include <sys/socket.h>
50#endif
51
52/* Ugly header files on some Linux boxes... */
53#if defined(HAVE_LINUX_IF_H)
54#include <linux/if.h>
55#elif defined(HAVE_NET_IF_H)
56#include <net/if.h>
57#endif
58
59#ifdef HAVE_NET_IF_TYPES_H
60#include <net/if_types.h>
61#endif
62
63#ifdef HAVE_NET_IF_DL_H
64#include <net/if_dl.h>
65#endif
66
67/* I'm not sure why this is needed... I do not have OpenBSD */
68#if defined(__OpenBSD__)
69#include <net/ppp_defs.h>
70#include <net/if_ppp.h>
71#endif
72
73#ifdef USE_BPF
74extern int bpfSize;
75struct PPPoEPacketStruct;
76void sessionDiscoveryPacket(struct PPPoEPacketStruct *packet);
77#define BPF_BUFFER_IS_EMPTY (bpfSize <= 0)
78#define BPF_BUFFER_HAS_DATA (bpfSize > 0)
79#define ethhdr ether_header
80#define h_dest ether_dhost
81#define h_source ether_shost
82#define h_proto ether_type
83#define	ETH_DATA_LEN ETHERMTU
84#define	ETH_ALEN ETHER_ADDR_LEN
85#else
86#undef USE_BPF
87#define BPF_BUFFER_IS_EMPTY 1
88#define BPF_BUFFER_HAS_DATA 0
89#endif
90
91#ifdef USE_DLPI
92#include <sys/ethernet.h>
93#define ethhdr ether_header
94#define	ETH_DATA_LEN ETHERMTU
95#define	ETH_ALEN ETHERADDRL
96#define h_dest ether_dhost.ether_addr_octet
97#define h_source ether_shost.ether_addr_octet
98#define h_proto ether_type
99
100/* cloned from dltest.h */
101#define         MAXDLBUF        8192
102#define         MAXDLADDR       1024
103#define         MAXWAIT         15
104#define         OFFADDR(s, n)   (u_char*)((char*)(s) + (int)(n))
105#define         CASERET(s)      case s:  return ("s")
106
107#endif
108
109/* Define various integer types -- assumes a char is 8 bits */
110#if SIZEOF_UNSIGNED_SHORT == 2
111typedef unsigned short UINT16_t;
112#elif SIZEOF_UNSIGNED_INT == 2
113typedef unsigned int UINT16_t;
114#else
115#error Could not find a 16-bit integer type
116#endif
117
118#if SIZEOF_UNSIGNED_SHORT == 4
119typedef unsigned short UINT32_t;
120#elif SIZEOF_UNSIGNED_INT == 4
121typedef unsigned int UINT32_t;
122#elif SIZEOF_UNSIGNED_LONG == 4
123typedef unsigned long UINT32_t;
124#else
125#error Could not find a 16-bit integer type
126#endif
127
128#ifdef HAVE_LINUX_IF_ETHER_H
129#include <linux/if_ether.h>
130#endif
131
132#include <netinet/in.h>
133
134#ifdef HAVE_NETINET_IF_ETHER_H
135#include <sys/types.h>
136
137#ifdef HAVE_SYS_SOCKET_H
138#include <sys/socket.h>
139#endif
140#ifndef HAVE_SYS_DLPI_H
141#include <netinet/if_ether.h>
142#endif
143#endif
144
145
146
147/* Ethernet frame types according to RFC 2516 */
148#define ETH_PPPOE_DISCOVERY 0x8863
149#define ETH_PPPOE_SESSION   0x8864
150
151/* But some brain-dead peers disobey the RFC, so frame types are variables */
152extern UINT16_t Eth_PPPOE_Discovery;
153extern UINT16_t Eth_PPPOE_Session;
154
155/* PPPoE codes */
156#define CODE_PADI           0x09
157#define CODE_PADO           0x07
158#define CODE_PADR           0x19
159#define CODE_PADS           0x65
160#define CODE_PADT           0xA7
161
162/* Extensions from draft-carrel-info-pppoe-ext-00 */
163/* I do NOT like PADM or PADN, but they are here for completeness */
164#define CODE_PADM           0xD3
165#define CODE_PADN           0xD4
166
167#define CODE_SESS           0x00
168
169/* PPPoE Tags */
170#define TAG_END_OF_LIST        0x0000
171#define TAG_SERVICE_NAME       0x0101
172#define TAG_AC_NAME            0x0102
173#define TAG_HOST_UNIQ          0x0103
174#define TAG_AC_COOKIE          0x0104
175#define TAG_VENDOR_SPECIFIC    0x0105
176#define TAG_RELAY_SESSION_ID   0x0110
177#define TAG_SERVICE_NAME_ERROR 0x0201
178#define TAG_AC_SYSTEM_ERROR    0x0202
179#define TAG_GENERIC_ERROR      0x0203
180
181/* Extensions from draft-carrel-info-pppoe-ext-00 */
182/* I do NOT like these tags one little bit */
183#define TAG_HURL               0x111
184#define TAG_MOTM               0x112
185#define TAG_IP_ROUTE_ADD       0x121
186
187/* Discovery phase states */
188#define STATE_SENT_PADI     0
189#define STATE_RECEIVED_PADO 1
190#define STATE_SENT_PADR     2
191#define STATE_SESSION       3
192#define STATE_TERMINATED    4
193
194/* How many PADI/PADS attempts? */
195#define MAX_PADI_ATTEMPTS 3
196
197/* Initial timeout for PADO/PADS */
198#define PADI_TIMEOUT 5
199
200/* States for scanning PPP frames */
201#define STATE_WAITFOR_FRAME_ADDR 0
202#define STATE_DROP_PROTO         1
203#define STATE_BUILDING_PACKET    2
204
205/* Special PPP frame characters */
206#define FRAME_ESC    0x7D
207#define FRAME_FLAG   0x7E
208#define FRAME_ADDR   0xFF
209#define FRAME_CTRL   0x03
210#define FRAME_ENC    0x20
211
212#define IPV4ALEN     4
213#define SMALLBUF   256
214
215/* A PPPoE Packet, including Ethernet headers */
216typedef struct PPPoEPacketStruct {
217    struct ethhdr ethHdr;	/* Ethernet header */
218#ifdef PACK_BITFIELDS_REVERSED
219    unsigned int type:4;	/* PPPoE Type (must be 1) */
220    unsigned int ver:4;		/* PPPoE Version (must be 1) */
221#else
222    unsigned int ver:4;		/* PPPoE Version (must be 1) */
223    unsigned int type:4;	/* PPPoE Type (must be 1) */
224#endif
225    unsigned int code:8;	/* PPPoE code */
226    unsigned int session:16;	/* PPPoE session */
227    unsigned int length:16;	/* Payload length */
228    unsigned char payload[ETH_DATA_LEN]; /* A bit of room to spare */
229} PPPoEPacket;
230
231/* Header size of a PPPoE packet */
232#define PPPOE_OVERHEAD 6  /* type, code, session, length */
233#define HDR_SIZE (sizeof(struct ethhdr) + PPPOE_OVERHEAD)
234#define MAX_PPPOE_PAYLOAD (ETH_DATA_LEN - PPPOE_OVERHEAD)
235#define MAX_PPPOE_MTU (MAX_PPPOE_PAYLOAD - 2)
236
237/* PPPoE Tag */
238
239typedef struct PPPoETagStruct {
240    unsigned int type:16;	/* tag type */
241    unsigned int length:16;	/* Length of payload */
242    unsigned char payload[ETH_DATA_LEN]; /* A LOT of room to spare */
243} PPPoETag;
244/* Header size of a PPPoE tag */
245#define TAG_HDR_SIZE 4
246
247/* Chunk to read from stdin */
248#define READ_CHUNK 4096
249
250/* Function passed to parsePacket */
251typedef void ParseFunc(UINT16_t type,
252		       UINT16_t len,
253		       unsigned char *data,
254		       void *extra);
255
256#define PPPINITFCS16    0xffff  /* Initial FCS value */
257
258/* Keep track of the state of a connection -- collect everything in
259   one spot */
260
261typedef struct PPPoEConnectionStruct {
262    int discoveryState;		/* Where we are in discovery */
263    int discoverySocket;	/* Raw socket for discovery frames */
264    int sessionSocket;		/* Raw socket for session frames */
265    unsigned char myEth[ETH_ALEN]; /* My MAC address */
266    unsigned char peerEth[ETH_ALEN]; /* Peer's MAC address */
267    UINT16_t session;		/* Session ID */
268    char *ifName;		/* Interface name */
269    char *serviceName;		/* Desired service name, if any */
270    char *acName;		/* Desired AC name, if any */
271    int synchronous;		/* Use synchronous PPP */
272    int useHostUniq;		/* Use Host-Uniq tag */
273    int printACNames;		/* Just print AC names */
274    int skipDiscovery;		/* Skip discovery */
275    int noDiscoverySocket;	/* Don't even open discovery socket */
276    int killSession;		/* Kill session and exit */
277    FILE *debugFile;		/* Debug file for dumping packets */
278    int numPADOs;		/* Number of PADO packets received */
279    PPPoETag cookie;		/* We have to send this if we get it */
280    PPPoETag relayId;		/* Ditto */
281} PPPoEConnection;
282
283/* Structure used to determine acceptable PADO or PADS packet */
284struct PacketCriteria {
285    PPPoEConnection *conn;
286    int acNameOK;
287    int serviceNameOK;
288    int seenACName;
289    int seenServiceName;
290};
291
292/* Function Prototypes */
293UINT16_t etherType(PPPoEPacket *packet);
294int openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr);
295int sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size);
296int receivePacket(int sock, PPPoEPacket *pkt, int *size);
297void fatalSys(char const *str);
298void rp_fatal(char const *str);
299void printErr(char const *str);
300void sysErr(char const *str);
301void dumpPacket(FILE *fp, PPPoEPacket *packet, char const *dir);
302void dumpHex(FILE *fp, unsigned char const *buf, int len);
303int parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra);
304void parseLogErrs(UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra);
305void syncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet);
306void asyncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet);
307void asyncReadFromEth(PPPoEConnection *conn, int sock, int clampMss);
308void syncReadFromEth(PPPoEConnection *conn, int sock, int clampMss);
309char *strDup(char const *str);
310void sendPADT(PPPoEConnection *conn, char const *msg);
311void sendPADTf(PPPoEConnection *conn, char const *fmt, ...);
312
313void sendSessionPacket(PPPoEConnection *conn,
314		       PPPoEPacket *packet, int len);
315void initPPP(void);
316void clampMSS(PPPoEPacket *packet, char const *dir, int clampMss);
317UINT16_t computeTCPChecksum(unsigned char *ipHdr, unsigned char *tcpHdr);
318UINT16_t pppFCS16(UINT16_t fcs, unsigned char *cp, int len);
319void discovery(PPPoEConnection *conn);
320unsigned char *findTag(PPPoEPacket *packet, UINT16_t tagType,
321		       PPPoETag *tag);
322
323#define SET_STRING(var, val) do { if (var) free(var); var = strDup(val); } while(0);
324
325#define CHECK_ROOM(cursor, start, len) \
326do {\
327    if (((cursor)-(start))+(len) > MAX_PPPOE_PAYLOAD) { \
328        syslog(LOG_ERR, "Would create too-long packet"); \
329        return; \
330    } \
331} while(0)
332
333/* True if Ethernet address is broadcast or multicast */
334#define NOT_UNICAST(e) ((e[0] & 0x01) != 0)
335#define BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) == 0xFF)
336#define NOT_BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) != 0xFF)
337