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Edit File: tcpd.h
/* * @(#) tcpd.h 1.5 96/03/19 16:22:24 * * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands. */ #ifndef _TCPWRAPPERS_TCPD_H #define _TCPWRAPPERS_TCPD_H /* Need definitions of struct sockaddr_in and FILE. */ #include <netinet/in.h> #include <stdio.h> #ifndef __BEGIN_DECLS #ifdef __cplusplus #define __BEGIN_DECLS extern "C" { #define __END_DECLS } #else #define __BEGIN_DECLS #define __END_DECLS #endif #endif __BEGIN_DECLS /* 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) */ #ifdef INET6 struct sockaddr *sin; /* socket address or 0 */ #else struct sockaddr_in *sin; /* socket address or 0 */ #endif 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) (struct request_info *); /* 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 */ extern char unknown[]; extern char paranoid[]; #define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid)) #define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0) /* Global functions. */ #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) extern void fromhost(); /* get/validate client host info */ #else #define fromhost sock_host /* no TLI support needed */ #endif extern int hosts_access(struct request_info *request); /* access control */ extern void shell_cmd(char *); /* execute shell command */ extern char *percent_x(char *, int, char *, struct request_info *); /* do %<char> expansion */ #ifdef INET6 extern void rfc931(struct sockaddr *, struct sockaddr *, char *); #else extern void rfc931(struct sockaddr_in *, struct sockaddr_in *, char *); #endif /* client name from RFC 931 daemon */ extern void clean_exit(struct request_info *); /* clean up and exit */ extern void refuse(struct request_info *); /* clean up and exit */ extern char *xgets(char *, int, FILE *); /* fgets() on steroids */ extern char *split_at(char *, int); /* strchr() and split */ extern unsigned long dot_quad_addr(char *); /* restricted inet_addr() */ /* Global variables. */ #ifdef HAVE_WEAKSYMS extern int allow_severity __attribute__ ((weak)); /* for connection logging */ extern int deny_severity __attribute__ ((weak)); /* for connection logging */ #else extern int allow_severity; /* for connection logging */ extern int deny_severity; /* for connection logging */ #endif extern char *hosts_allow_table; /* for verification mode redirection */ extern 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. */ #ifdef __STDC__ extern struct request_info *request_init(struct request_info *,...); extern struct request_info *request_set(struct request_info *,...); extern int hosts_ctl(char *daemon, char *client_name, char *client_addr, char *client_user); #else extern struct request_info *request_init(); /* initialize request */ extern struct request_info *request_set(); /* update request structure */ #endif #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(struct request_info *); /* client user */ extern char *eval_hostname(struct host_info *); /* printable hostname */ extern char *eval_hostaddr(struct host_info *); /* printable host address */ extern char *eval_hostinfo(struct host_info *); /* host name or address */ extern char *eval_client(struct request_info *);/* whatever is available */ extern char *eval_server(struct request_info *);/* whatever is available */ #ifdef INET6 extern char *eval_port(struct sockaddr *); #else extern char *eval_port(struct sockaddr_in *); #endif #define eval_daemon(r) ((r)->daemon) /* daemon process name */ #define eval_pid(r) ((r)->pid) /* process id */ /* Socket-specific methods, including DNS hostname lookups. */ /* look up endpoint addresses */ extern void sock_host(struct request_info *); /* translate address to hostname */ extern void sock_hostname(struct host_info *); /* address to printable address */ extern void sock_hostaddr(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. */ #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>. */ #ifdef __STDC__ extern void tcpd_warn(char *, ...); /* report problem and proceed */ extern void tcpd_jump(char *, ...); /* report problem and jump */ #else extern void tcpd_warn(); extern void tcpd_jump(); #endif struct tcpd_context { char *file; /* current file */ int line; /* current line */ }; extern struct tcpd_context tcpd_context; /* * 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. */ extern void process_options(char *, struct request_info *);/* execute options */ extern int dry_run; /* verification flag */ /* Bug workarounds. */ #ifdef INET_ADDR_BUG /* inet_addr() returns struct */ #define inet_addr fix_inet_addr extern long fix_inet_addr(); #endif #ifdef BROKEN_FGETS /* partial reads from sockets */ #define fgets fix_fgets extern char *fix_fgets(); #endif #ifdef RECVFROM_BUG /* no address family info */ #define recvfrom fix_recvfrom extern int fix_recvfrom(); #endif #ifdef GETPEERNAME_BUG /* claims success with UDP */ #define getpeername fix_getpeername extern int fix_getpeername(); #endif #ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ #define gethostbyname fix_gethostbyname extern struct hostent *fix_gethostbyname(); #endif #ifdef USE_STRSEP /* libc calls strtok() */ #define strtok fix_strtok extern char *fix_strtok(); #endif #ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ #define strtok my_strtok extern char *my_strtok(); #endif __END_DECLS #endif