pppd.h

经典的ppp程序

/*
 * pppd.h - PPP daemon global declarations.
 *
 * Copyright (c) 1989 Carnegie Mellon University.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by Carnegie Mellon University.  The name of the
 * University may not 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 MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * $Id: pppd.h,v 1.59 2001/03/12 22:58:59 paulus Exp $
 */

/*
 * TODO:
 */

#ifndef __PPPD_H__
#define __PPPD_H__

#include <stdio.h>		/* for FILE */
#include <limits.h>		/* for NGROUPS_MAX */
#include <sys/param.h>		/* for MAXPATHLEN and BSD4_4, if defined */
#include <sys/types.h>		/* for u_int32_t, if defined */
#include <sys/time.h>		/* for struct timeval */
#include <net/ppp_defs.h>
#include "patchlevel.h"

#if defined(__STDC__)
#include <stdarg.h>
#define __V(x)	x
#else
#include <varargs.h>
#define __V(x)	(va_alist) va_dcl
#define const
#define volatile
#endif

#ifdef INET6
#include "eui64.h"
#endif

/*
 * Limits.
 */

#define NUM_PPP		1	/* One PPP interface supported (per process) */
#define MAXWORDLEN	1024	/* max length of word in file (incl null) */
#define MAXARGS		1	/* max # args to a command */
#define MAXNAMELEN	256	/* max length of hostname or name for auth */
#define MAXSECRETLEN	256	/* max length of password or secret */

/*
 * Option descriptor structure.
 */

typedef unsigned char	bool;

enum opt_type {
	o_special_noarg = 0,
	o_special = 1,
	o_bool,
	o_int,
	o_uint32,
	o_string,
	o_wild,
};

typedef struct {
	char	*name;		/* name of the option */
	enum opt_type type;
	void	*addr;
	char	*description;
	int	flags;
	void	*addr2;
	int	upper_limit;
	int	lower_limit;
	const char *source;
	short int priority;
	short int winner;
} option_t;

/* Values for flags */
#define OPT_VALUE	0xff	/* mask for presupplied value */
#define OPT_HEX		0x100	/* int option is in hex */
#define OPT_NOARG	0x200	/* option doesn't take argument */
#define OPT_OR		0x400	/* OR in argument to value */
#define OPT_INC		0x800	/* increment value */
#define OPT_PRIV	0x1000	/* privileged option */
#define OPT_STATIC	0x2000	/* string option goes into static array */
#define OPT_LLIMIT	0x4000	/* check value against lower limit */
#define OPT_ULIMIT	0x8000	/* check value against upper limit */
#define OPT_LIMITS	(OPT_LLIMIT|OPT_ULIMIT)
#define OPT_ZEROOK	0x10000	/* 0 value is OK even if not within limits */
#define OPT_HIDE	0x10000	/* for o_string, print value as ?????? */
#define OPT_A2LIST	0x10000 /* for o_special, keep list of values */
#define OPT_NOINCR	0x20000	/* value mustn't be increased */
#define OPT_ZEROINF	0x40000	/* with OPT_NOINCR, 0 == infinity */
#define OPT_PRIO	0x80000	/* process option priorities for this option */
#define OPT_PRIOSUB	0x100000 /* subsidiary member of priority group */
#define OPT_ALIAS	0x200000 /* option is alias for previous option */
#define OPT_A2COPY	0x400000 /* addr2 -> second location to rcv value */
#define OPT_ENABLE	0x800000 /* use *addr2 as enable for option */
#define OPT_A2CLR	0x1000000 /* clear *(bool *)addr2 */
#define OPT_PRIVFIX	0x2000000 /* user can't override if set by root */
#define OPT_INITONLY	0x4000000 /* option can only be set in init phase */
#define OPT_DEVEQUIV	0x8000000 /* equiv to device name */
#define OPT_DEVNAM	(OPT_INITONLY | OPT_DEVEQUIV)
#define OPT_A2PRINTER	0x10000000 /* *addr2 is a fn for printing option */
#define OPT_A2STRVAL	0x20000000 /* *addr2 points to current string value */
#define OPT_NOPRINT	0x40000000 /* don't print this option at all */

#define OPT_VAL(x)	((x) & OPT_VALUE)

/* Values for priority */
#define OPRIO_DEFAULT	0	/* a default value */
#define OPRIO_CFGFILE	1	/* value from a configuration file */
#define OPRIO_CMDLINE	2	/* value from the command line */
#define OPRIO_SECFILE	3	/* value from options in a secrets file */
#define OPRIO_ROOT	100	/* added to priority if OPT_PRIVFIX && root */

#ifndef GIDSET_TYPE
#define GIDSET_TYPE	gid_t
#endif

/* Structure representing a list of permitted IP addresses. */
struct permitted_ip {
    int		permit;		/* 1 = permit, 0 = forbid */
    u_int32_t	base;		/* match if (addr & mask) == base */
    u_int32_t	mask;		/* base and mask are in network byte order */
};

/*
 * Unfortunately, the linux kernel driver uses a different structure
 * for statistics from the rest of the ports.
 * This structure serves as a common representation for the bits
 * pppd needs.
 */
struct pppd_stats {
    unsigned int	bytes_in;
    unsigned int	bytes_out;
};

/* Used for storing a sequence of words.  Usually malloced. */
struct wordlist {
    struct wordlist	*next;
    char		*word;
};

/* An endpoint discriminator, used with multilink. */
#define MAX_ENDP_LEN	20	/* maximum length of discriminator value */
struct epdisc {
    unsigned char	class;
    unsigned char	length;
    unsigned char	value[MAX_ENDP_LEN];
};

/* values for epdisc.class */
#define EPD_NULL	0	/* null discriminator, no data */
#define EPD_LOCAL	1
#define EPD_IP		2
#define EPD_MAC		3
#define EPD_MAGIC	4
#define EPD_PHONENUM	5

typedef void (*notify_func) __P((void *, int));

struct notifier {
    struct notifier *next;
    notify_func	    func;
    void	    *arg;
};

/*
 * Global variables.
 */

extern int	hungup;		/* Physical layer has disconnected */
extern int	ifunit;		/* Interface unit number */
extern char	ifname[];	/* Interface name */
extern char	hostname[];	/* Our hostname */
extern u_char	outpacket_buf[]; /* Buffer for outgoing packets */
extern int	phase;		/* Current state of link - see values below */
extern int	baud_rate;	/* Current link speed in bits/sec */
extern char	*progname;	/* Name of this program */
extern int	redirect_stderr;/* Connector's stderr should go to file */
extern char	peer_authname[];/* Authenticated name of peer */
extern int	privileged;	/* We were run by real-uid root */
extern int	need_holdoff;	/* Need holdoff period after link terminates */
extern char	**script_env;	/* Environment variables for scripts */
extern int	detached;	/* Have detached from controlling tty */
extern GIDSET_TYPE groups[NGROUPS_MAX];	/* groups the user is in */
extern int	ngroups;	/* How many groups valid in groups */
extern struct pppd_stats link_stats; /* byte/packet counts etc. for link */
extern int	link_stats_valid; /* set if link_stats is valid */
extern int	link_connect_time; /* time the link was up for */
extern int	using_pty;	/* using pty as device (notty or pty opt.) */
extern int	log_to_fd;	/* logging to this fd as well as syslog */
extern bool	log_default;	/* log_to_fd is default (stdout) */
extern char	*no_ppp_msg;	/* message to print if ppp not in kernel */
extern volatile int status;	/* exit status for pppd */
extern bool	devnam_fixed;	/* can no longer change devnam */
extern int	unsuccess;	/* # unsuccessful connection attempts */
extern int	do_callback;	/* set if we want to do callback next */
extern int	doing_callback;	/* set if this is a callback */
extern char	ppp_devnam[MAXPATHLEN];
extern struct notifier *pidchange;   /* for notifications of pid changing */
extern struct notifier *phasechange; /* for notifications of phase changes */
extern struct notifier *exitnotify;  /* for notification that we're exiting */
extern struct notifier *sigreceived; /* notification of received signal */
extern int	listen_time;	/* time to listen first (ms) */

/* Values for do_callback and doing_callback */
#define CALLBACK_DIALIN		1	/* we are expecting the call back */
#define CALLBACK_DIALOUT	2	/* we are dialling out to call back */

/*
 * Variables set by command-line options.
 */

extern int	debug;		/* Debug flag */
extern int	kdebugflag;	/* Tell kernel to print debug messages */
extern int	default_device;	/* Using /dev/tty or equivalent */
extern char	devnam[MAXPATHLEN];	/* Device name */
extern int	crtscts;	/* Use hardware flow control */
extern bool	modem;		/* Use modem control lines */
extern int	inspeed;	/* Input/Output speed requested */
extern u_int32_t netmask;	/* IP netmask to set on interface */
extern bool	lockflag;	/* Create lock file to lock the serial dev */
extern bool	nodetach;	/* Don't detach from controlling tty */
extern bool	updetach;	/* Detach from controlling tty when link up */
extern char	*initializer;	/* Script to initialize physical link */
extern char	*connect_script; /* Script to establish physical link */
extern char	*disconnect_script; /* Script to disestablish physical link */
extern char	*welcomer;	/* Script to welcome client after connection */
extern char	*ptycommand;	/* Command to run on other side of pty */
extern int	maxconnect;	/* Maximum connect time (seconds) */
extern char	user[MAXNAMELEN];/* Our name for authenticating ourselves */
extern char	passwd[MAXSECRETLEN];	/* Password for PAP or CHAP */
extern bool	auth_required;	/* Peer is required to authenticate */
extern bool	persist;	/* Reopen link after it goes down */
extern bool	uselogin;	/* Use /etc/passwd for checking PAP */
extern char	our_name[MAXNAMELEN];/* Our name for authentication purposes */
extern char	remote_name[MAXNAMELEN]; /* Peer's name for authentication */
extern bool	explicit_remote;/* remote_name specified with remotename opt */
extern bool	demand;		/* Do dial-on-demand */
extern char	*ipparam;	/* Extra parameter for ip up/down scripts */
extern bool	cryptpap;	/* Others' PAP passwords are encrypted */
extern int	idle_time_limit;/* Shut down link if idle for this long */
extern int	holdoff;	/* Dead time before restarting */
extern bool	holdoff_specified; /* true if user gave a holdoff value */
extern bool	notty;		/* Stdin/out is not a tty */
extern char	*pty_socket;	/* Socket to connect to pty */
extern char	*record_file;	/* File to record chars sent/received */
extern bool	sync_serial;	/* Device is synchronous serial device */
extern int	maxfail;	/* Max # of unsuccessful connection attempts */
extern char	linkname[MAXPATHLEN]; /* logical name for link */
extern bool	tune_kernel;	/* May alter kernel settings as necessary */
extern int	connect_delay;	/* Time to delay after connect script */
extern int	max_data_rate;	/* max bytes/sec through charshunt */
extern int	req_unit;	/* interface unit number to use */
extern bool	multilink;	/* enable multilink operation */
extern bool	noendpoint;	/* don't send or accept endpt. discrim. */
extern char	*bundle_name;	/* bundle name for multilink */
extern bool	dump_options;	/* print out option values */
extern bool	dryrun;		/* check everything, print options, exit */

#ifdef PPP_FILTER
extern struct	bpf_program pass_filter;   /* Filter for pkts to pass */
extern struct	bpf_program active_filter; /* Filter for link-active pkts */
#endif

#ifdef MSLANMAN
extern bool	ms_lanman;	/* Use LanMan password instead of NT */
				/* Has meaning only with MS-CHAP challenges */
#endif

extern char *current_option;	/* the name of the option being parsed */
extern int  privileged_option;	/* set iff the current option came from root */
extern char *option_source;	/* string saying where the option came from */
extern int  option_priority;	/* priority of current options */

/*
 * Values for phase.
 */
#define PHASE_DEAD		0
#define PHASE_INITIALIZE	1
#define PHASE_SERIALCONN	2
#define PHASE_DORMANT		3
#define PHASE_ESTABLISH		4
#define PHASE_AUTHENTICATE	5
#define PHASE_CALLBACK		6
#define PHASE_NETWORK		7
#define PHASE_RUNNING		8
#define PHASE_TERMINATE		9
#define PHASE_DISCONNECT	10
#define PHASE_HOLDOFF		11

/*
 * The following struct gives the addresses of procedures to call
 * for a particular protocol.
 */
struct protent {
    u_short protocol;		/* PPP protocol number */
    /* Initialization procedure */
    void (*init) __P((int unit));
    /* Process a received packet */
    void (*input) __P((int unit, u_char *pkt, int len));
    /* Process a received protocol-reject */
    void (*protrej) __P((int unit));
    /* Lower layer has come up */
    void (*lowerup) __P((int unit));
    /* Lower layer has gone down */
    void (*lowerdown) __P((int unit));
    /* Open the protocol */
    void (*open) __P((int unit));
    /* Close the protocol */
    void (*close) __P((int unit, char *reason));
    /* Print a packet in readable form */
    int  (*printpkt) __P((u_char *pkt, int len,
			  void (*printer) __P((void *, char *, ...)),
			  void *arg));
    /* Process a received data packet */
    void (*datainput) __P((int unit, u_char *pkt, int len));
    bool enabled_flag;		/* 0 iff protocol is disabled */
    char *name;			/* Text name of protocol */
    char *data_name;		/* Text name of corresponding data protocol */
    option_t *options;		/* List of command-line options */
    /* Check requested options, assign defaults */
    void (*check_options) __P((void));
    /* Configure interface for demand-dial */
    int  (*demand_conf) __P((int unit));
    /* Say whether to bring up link for this pkt */
    int  (*active_pkt) __P((u_char *pkt, int len));
};

/* Table of pointers to supported protocols */
extern struct protent *protocols[];

/*
 * This struct contains pointers to a set of procedures for
 * doing operations on a "channel".  A channel provides a way
 * to send and receive PPP packets - the canonical example is
 * a serial port device in PPP line discipline (or equivalently
 * with PPP STREAMS modules pushed onto it).
 */
struct channel {
	/* set of options for this channel */
	option_t *options;
	/* find and process a per-channel options file */
	void (*process_extra_options) __P((void));
	/* check all the options that have been given */
	void (*check_options) __P((void));
	/* get the channel ready to do PPP, return a file descriptor */
	int  (*connect) __P((void));
	/* we're finished with the channel */
	void (*disconnect) __P((void));
	/* put the channel into PPP `mode' */
	int  (*establish_ppp) __P((int));
	/* take the channel out of PPP `mode', restore loopback if demand */
	void (*disestablish_ppp) __P((int));
	/* set the transmit-side PPP parameters of the channel */
	void (*send_config) __P((int, u_int32_t, int, int));
	/* set the receive-side PPP parameters of the channel */
	void (*recv_config) __P((int, u_int32_t, int, int));
	/* cleanup on error or normal exit */
	void (*cleanup) __P((void));
	/* close the device, called in children after fork */
	void (*close) __P((void));
};

extern struct channel *the_channel;

#define ppp_send_config(unit, mtu, accm, pc, acc)			 \
do {									 \
	if (the_channel->send_config)					 \
		(*the_channel->send_config)((mtu), (accm), (pc), (acc)); \
} while (0)

#define ppp_recv_config(unit, mtu, accm, pc, acc)			 \
do {									 \
	if (the_channel->send_config)					 \
		(*the_channel->recv_config)((mtu), (accm), (pc), (acc)); \
} while (0)

/*
 * Prototypes.