LCOM1920-T02G10

/*        $NetBSD: tcpd.h,v 1.14 2012/03/22 22:59:43 joerg Exp $        */

 /*

  * @(#) tcpd.h 1.5 96/03/19 16:22:24

  * 

  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.

  */

#include <sys/cdefs.h>

#include <stdio.h>

/* Structure to describe one communications endpoint. */

#define STRING_LENGTH        128                /* hosts, users, processes */

struct host_info {

    char    name[STRING_LENGTH];        /* access via eval_hostname(host) */

    char    addr[STRING_LENGTH];        /* access via eval_hostaddr(host) */

    struct sockaddr *sin;                /* socket address or 0 */

    struct t_unitdata *unit;                /* TLI transport address or 0 */

    struct request_info *request;        /* for shared information */

};

/* Structure to describe what we know about a service request. */

struct request_info {

    int     fd;                                /* socket handle */

    char    user[STRING_LENGTH];        /* access via eval_user(request) */

    char    daemon[STRING_LENGTH];        /* access via eval_daemon(request) */

    char    pid[10];                        /* access via eval_pid(request) */

    struct host_info client[1];                /* client endpoint info */

    struct host_info server[1];                /* server endpoint info */

    void (*sink)(int);                        /* datagram sink function or 0 */

    void (*hostname)(struct host_info *); /* address to printable hostname */

    void (*hostaddr)(struct host_info *); /* address to printable address */

    void (*cleanup)(void);                /* cleanup function or 0 */

    struct netconfig *config;                /* netdir handle */

};

/* Common string operations. Less clutter should be more readable. */

#define STRN_CPY(d,s,l)        { strncpy((d),(s),(l)); (d)[(l)-1] = 0; }

#define STRN_EQ(x,y,l)        (strncasecmp((x),(y),(l)) == 0)

#define STRN_NE(x,y,l)        (strncasecmp((x),(y),(l)) != 0)

#define STR_EQ(x,y)        (strcasecmp((x),(y)) == 0)

#define STR_NE(x,y)        (strcasecmp((x),(y)) != 0)

 /*

  * Initially, all above strings have the empty value. Information that

  * cannot be determined at runtime is set to "unknown", so that we can

  * distinguish between `unavailable' and `not yet looked up'. A hostname

  * that we do not believe in is set to "paranoid".

  */

#define STRING_UNKNOWN        "unknown"        /* lookup failed */

#define STRING_PARANOID        "paranoid"        /* hostname conflict */

__BEGIN_DECLS

extern char unknown[];

extern char paranoid[];

__END_DECLS

#define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid))

#define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0)

/* Global functions. */

__BEGIN_DECLS

#define fromhost sock_host                /* no TLI support needed */

extern int hosts_access                        /* access control */

                (struct request_info *);

extern int hosts_ctl                        /* limited interface to hosts_access */

                (char *, char *, char *, char *);

extern void shell_cmd                        /* execute shell command */

                (char *);

extern char *percent_x                        /* do %<char> expansion */

                (char *, int, char *, struct request_info *);

extern void rfc931                        /* client name from RFC 931 daemon */

                (struct sockaddr *, struct sockaddr *, char *);

__dead extern void clean_exit                /* clean up and exit */

                (struct request_info *);

__dead extern void refuse                /* clean up and exit */

                (struct request_info *);

extern char *xgets                        /* fgets() on steroids */

                (char *, int, FILE *);

extern char *split_at                        /* strchr() and split */

                (char *, int);

extern int dot_quad_addr        /* restricted inet_aton() */

                (char *, unsigned long *);

/* Global variables. */

extern int allow_severity;                /* for connection logging */

extern int deny_severity;                /* for connection logging */

extern const char *hosts_allow_table;        /* for verification mode redirection */

extern const char *hosts_deny_table;        /* for verification mode redirection */

extern int hosts_access_verbose;        /* for verbose matching mode */

extern int rfc931_timeout;                /* user lookup timeout */

extern int resident;                        /* > 0 if resident process */

 /*

  * Routines for controlled initialization and update of request structure

  * attributes. Each attribute has its own key.

  */

extern struct request_info *request_init        /* initialize request */

                (struct request_info *,...);

extern struct request_info *request_set                /* update request structure */

                (struct request_info *,...);

#define RQ_FILE                1                /* file descriptor */

#define RQ_DAEMON        2                /* server process (argv[0]) */

#define RQ_USER                3                /* client user name */

#define RQ_CLIENT_NAME        4                /* client host name */

#define RQ_CLIENT_ADDR        5                /* client host address */

#define RQ_CLIENT_SIN        6                /* client endpoint (internal) */

#define RQ_SERVER_NAME        7                /* server host name */

#define RQ_SERVER_ADDR        8                /* server host address */

#define RQ_SERVER_SIN        9                /* server endpoint (internal) */

 /*

  * Routines for delayed evaluation of request attributes. Each attribute

  * type has its own access method. The trivial ones are implemented by

  * macros. The other ones are wrappers around the transport-specific host

  * name, address, and client user lookup methods. The request_info and

  * host_info structures serve as caches for the lookup results.

  */

extern char *eval_user                        /* client user */

                (struct request_info *);

extern char *eval_hostname                /* printable hostname */

                (struct host_info *);

extern char *eval_hostaddr                /* printable host address */

                (struct host_info *);

extern char *eval_hostinfo                /* host name or address */

                (struct host_info *);

extern char *eval_client                /* whatever is available */

                (struct request_info *);

extern char *eval_server                /* whatever is available */

                (struct request_info *);

#define eval_daemon(r)        ((r)->daemon)        /* daemon process name */

#define eval_pid(r)        ((r)->pid)        /* process id */

/* Socket-specific methods, including DNS hostname lookups. */

extern void sock_host                        /* look up endpoint addresses */

                (struct request_info *);

extern void sock_hostname                /* translate address to hostname */

                (struct host_info *);

extern void sock_hostaddr                /* address to printable address */

                (struct host_info *);

#define sock_methods(r) \

        { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; }

/* The System V Transport-Level Interface (TLI) interface. */

#if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT)

extern void tli_host                        /* look up endpoint addresses etc. */

                (struct request_info *);

#endif

 /*

  * Problem reporting interface. Additional file/line context is reported

  * when available. The jump buffer (tcpd_buf) is not declared here, or

  * everyone would have to include <setjmp.h>.

  */

/* Report problem and proceed */

void tcpd_warn(const char *, ...) __printflike(1, 2);

/* Report problem and jump */

void tcpd_jump(const char *, ...) __dead __printflike(1, 2);

__END_DECLS

struct tcpd_context {

    const char *file;                        /* current file */

    int     line;                        /* current line */

};

__BEGIN_DECLS

extern struct tcpd_context tcpd_context;

__END_DECLS

 /*

  * While processing access control rules, error conditions are handled by

  * jumping back into the hosts_access() routine. This is cleaner than

  * checking the return value of each and every silly little function. The

  * (-1) returns are here because zero is already taken by longjmp().

  */

#define AC_PERMIT        1                /* permit access */

#define AC_DENY                (-1)                /* deny_access */

#define AC_ERROR        AC_DENY                /* XXX */

 /*

  * In verification mode an option function should just say what it would do,

  * instead of really doing it. An option function that would not return

  * should clear the dry_run flag to inform the caller of this unusual

  * behavior.

  */

__BEGIN_DECLS

extern void process_options                /* execute options */

                (char *, struct request_info *);

extern int dry_run;                        /* verification flag */

extern void fix_options                        /* get rid of IP-level socket options */

                (struct request_info *);

__END_DECLS