tcpd.h revision 44743
1 /* 2 * @(#) tcpd.h 1.5 96/03/19 16:22:24 3 * 4 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands. 5 */ 6 7/* Structure to describe one communications endpoint. */ 8 9#define STRING_LENGTH 128 /* hosts, users, processes */ 10 11struct host_info { 12 char name[STRING_LENGTH]; /* access via eval_hostname(host) */ 13 char addr[STRING_LENGTH]; /* access via eval_hostaddr(host) */ 14 struct sockaddr_in *sin; /* socket address or 0 */ 15 struct t_unitdata *unit; /* TLI transport address or 0 */ 16 struct request_info *request; /* for shared information */ 17}; 18 19/* Structure to describe what we know about a service request. */ 20 21struct request_info { 22 int fd; /* socket handle */ 23 char user[STRING_LENGTH]; /* access via eval_user(request) */ 24 char daemon[STRING_LENGTH]; /* access via eval_daemon(request) */ 25 char pid[10]; /* access via eval_pid(request) */ 26 struct host_info client[1]; /* client endpoint info */ 27 struct host_info server[1]; /* server endpoint info */ 28 void (*sink) (); /* datagram sink function or 0 */ 29 void (*hostname) (); /* address to printable hostname */ 30 void (*hostaddr) (); /* address to printable address */ 31 void (*cleanup) (); /* cleanup function or 0 */ 32 struct netconfig *config; /* netdir handle */ 33}; 34 35/* Common string operations. Less clutter should be more readable. */ 36 37#define STRN_CPY(d,s,l) { strncpy((d),(s),(l)); (d)[(l)-1] = 0; } 38 39#define STRN_EQ(x,y,l) (strncasecmp((x),(y),(l)) == 0) 40#define STRN_NE(x,y,l) (strncasecmp((x),(y),(l)) != 0) 41#define STR_EQ(x,y) (strcasecmp((x),(y)) == 0) 42#define STR_NE(x,y) (strcasecmp((x),(y)) != 0) 43 44 /* 45 * Initially, all above strings have the empty value. Information that 46 * cannot be determined at runtime is set to "unknown", so that we can 47 * distinguish between `unavailable' and `not yet looked up'. A hostname 48 * that we do not believe in is set to "paranoid". 49 */ 50 51#define STRING_UNKNOWN "unknown" /* lookup failed */ 52#define STRING_PARANOID "paranoid" /* hostname conflict */ 53 54extern char unknown[]; 55extern char paranoid[]; 56 57#define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid)) 58 59#define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0) 60 61/* Global functions. */ 62 63#if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 64extern void fromhost(); /* get/validate client host info */ 65#else 66#define fromhost sock_host /* no TLI support needed */ 67#endif 68 69extern int hosts_access(); /* access control */ 70extern void shell_cmd(); /* execute shell command */ 71extern char *percent_x(); /* do %<char> expansion */ 72extern void rfc931(); /* client name from RFC 931 daemon */ 73extern void clean_exit(); /* clean up and exit */ 74extern void refuse(); /* clean up and exit */ 75extern char *xgets(); /* fgets() on steroids */ 76extern char *split_at(); /* strchr() and split */ 77extern unsigned long dot_quad_addr(); /* restricted inet_addr() */ 78 79/* Global variables. */ 80 81extern int allow_severity; /* for connection logging */ 82extern int deny_severity; /* for connection logging */ 83extern char *hosts_allow_table; /* for verification mode redirection */ 84extern char *hosts_deny_table; /* for verification mode redirection */ 85extern int hosts_access_verbose; /* for verbose matching mode */ 86extern int rfc931_timeout; /* user lookup timeout */ 87extern int resident; /* > 0 if resident process */ 88 89 /* 90 * Routines for controlled initialization and update of request structure 91 * attributes. Each attribute has its own key. 92 */ 93 94#ifdef __STDC__ 95extern struct request_info *request_init(struct request_info *,...); 96extern struct request_info *request_set(struct request_info *,...); 97#else 98extern struct request_info *request_init(); /* initialize request */ 99extern struct request_info *request_set(); /* update request structure */ 100#endif 101 102#define RQ_FILE 1 /* file descriptor */ 103#define RQ_DAEMON 2 /* server process (argv[0]) */ 104#define RQ_USER 3 /* client user name */ 105#define RQ_CLIENT_NAME 4 /* client host name */ 106#define RQ_CLIENT_ADDR 5 /* client host address */ 107#define RQ_CLIENT_SIN 6 /* client endpoint (internal) */ 108#define RQ_SERVER_NAME 7 /* server host name */ 109#define RQ_SERVER_ADDR 8 /* server host address */ 110#define RQ_SERVER_SIN 9 /* server endpoint (internal) */ 111 112 /* 113 * Routines for delayed evaluation of request attributes. Each attribute 114 * type has its own access method. The trivial ones are implemented by 115 * macros. The other ones are wrappers around the transport-specific host 116 * name, address, and client user lookup methods. The request_info and 117 * host_info structures serve as caches for the lookup results. 118 */ 119 120extern char *eval_user(); /* client user */ 121extern char *eval_hostname(); /* printable hostname */ 122extern char *eval_hostaddr(); /* printable host address */ 123extern char *eval_hostinfo(); /* host name or address */ 124extern char *eval_client(); /* whatever is available */ 125extern char *eval_server(); /* whatever is available */ 126#define eval_daemon(r) ((r)->daemon) /* daemon process name */ 127#define eval_pid(r) ((r)->pid) /* process id */ 128 129/* Socket-specific methods, including DNS hostname lookups. */ 130 131extern void sock_host(); /* look up endpoint addresses */ 132extern void sock_hostname(); /* translate address to hostname */ 133extern void sock_hostaddr(); /* address to printable address */ 134#define sock_methods(r) \ 135 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; } 136 137/* The System V Transport-Level Interface (TLI) interface. */ 138 139#if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 140extern void tli_host(); /* look up endpoint addresses etc. */ 141#endif 142 143 /* 144 * Problem reporting interface. Additional file/line context is reported 145 * when available. The jump buffer (tcpd_buf) is not declared here, or 146 * everyone would have to include <setjmp.h>. 147 */ 148 149#ifdef __STDC__ 150extern void tcpd_warn(char *, ...); /* report problem and proceed */ 151extern void tcpd_jump(char *, ...); /* report problem and jump */ 152#else 153extern void tcpd_warn(); 154extern void tcpd_jump(); 155#endif 156 157struct tcpd_context { 158 char *file; /* current file */ 159 int line; /* current line */ 160}; 161extern struct tcpd_context tcpd_context; 162 163 /* 164 * While processing access control rules, error conditions are handled by 165 * jumping back into the hosts_access() routine. This is cleaner than 166 * checking the return value of each and every silly little function. The 167 * (-1) returns are here because zero is already taken by longjmp(). 168 */ 169 170#define AC_PERMIT 1 /* permit access */ 171#define AC_DENY (-1) /* deny_access */ 172#define AC_ERROR AC_DENY /* XXX */ 173 174 /* 175 * In verification mode an option function should just say what it would do, 176 * instead of really doing it. An option function that would not return 177 * should clear the dry_run flag to inform the caller of this unusual 178 * behavior. 179 */ 180 181extern void process_options(); /* execute options */ 182extern int dry_run; /* verification flag */ 183 184/* Bug workarounds. */ 185 186#ifdef INET_ADDR_BUG /* inet_addr() returns struct */ 187#define inet_addr fix_inet_addr 188extern long fix_inet_addr(); 189#endif 190 191#ifdef BROKEN_FGETS /* partial reads from sockets */ 192#define fgets fix_fgets 193extern char *fix_fgets(); 194#endif 195 196#ifdef RECVFROM_BUG /* no address family info */ 197#define recvfrom fix_recvfrom 198extern int fix_recvfrom(); 199#endif 200 201#ifdef GETPEERNAME_BUG /* claims success with UDP */ 202#define getpeername fix_getpeername 203extern int fix_getpeername(); 204#endif 205 206#ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ 207#define gethostbyname fix_gethostbyname 208extern struct hostent *fix_gethostbyname(); 209#endif 210 211#ifdef USE_STRSEP /* libc calls strtok() */ 212#define strtok fix_strtok 213extern char *fix_strtok(); 214#endif 215 216#ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ 217#define strtok my_strtok 218extern char *my_strtok(); 219#endif 220