/* $NetBSD: tcpd.h,v 1.15 2015/10/14 15:54:21 christos 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 *, ...) __sysloglike(1, 2);
/* Report problem and jump */
void tcpd_jump(const char *, ...) __dead __sysloglike(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