tcpd.h revision 277281
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 * $FreeBSD: stable/10/contrib/tcp_wrappers/tcpd.h 277281 2015-01-17 01:20:28Z pfg $ 7 */ 8 9/* Structure to describe one communications endpoint. */ 10 11#define STRING_LENGTH 128 /* hosts, users, processes */ 12 13struct host_info { 14 char name[STRING_LENGTH]; /* access via eval_hostname(host) */ 15 char addr[STRING_LENGTH]; /* access via eval_hostaddr(host) */ 16#ifdef INET6 17 struct sockaddr *sin; /* socket address or 0 */ 18#else 19 struct sockaddr_in *sin; /* socket address or 0 */ 20#endif 21 struct t_unitdata *unit; /* TLI transport address or 0 */ 22 struct request_info *request; /* for shared information */ 23}; 24 25/* Structure to describe what we know about a service request. */ 26 27struct request_info { 28 int fd; /* socket handle */ 29 char user[STRING_LENGTH]; /* access via eval_user(request) */ 30 char daemon[STRING_LENGTH]; /* access via eval_daemon(request) */ 31 char pid[10]; /* access via eval_pid(request) */ 32 struct host_info client[1]; /* client endpoint info */ 33 struct host_info server[1]; /* server endpoint info */ 34 void (*sink) (int); /* datagram sink function or 0 */ 35 void (*hostname) (struct host_info *); /* address to printable hostname */ 36 void (*hostaddr) (struct host_info *); /* address to printable address */ 37 void (*cleanup) (struct request_info *); /* cleanup function or 0 */ 38 struct netconfig *config; /* netdir handle */ 39}; 40 41/* Common string operations. Less clutter should be more readable. */ 42 43#define STRN_CPY(d,s,l) { strncpy((d),(s),(l)); (d)[(l)-1] = 0; } 44 45#define STRN_EQ(x,y,l) (strncasecmp((x),(y),(l)) == 0) 46#define STRN_NE(x,y,l) (strncasecmp((x),(y),(l)) != 0) 47#define STR_EQ(x,y) (strcasecmp((x),(y)) == 0) 48#define STR_NE(x,y) (strcasecmp((x),(y)) != 0) 49 50 /* 51 * Initially, all above strings have the empty value. Information that 52 * cannot be determined at runtime is set to "unknown", so that we can 53 * distinguish between `unavailable' and `not yet looked up'. A hostname 54 * that we do not believe in is set to "paranoid". 55 */ 56 57#define STRING_UNKNOWN "unknown" /* lookup failed */ 58#define STRING_PARANOID "paranoid" /* hostname conflict */ 59 60extern char unknown[]; 61extern char paranoid[]; 62 63#define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid)) 64 65#define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0) 66 67/* Global functions. */ 68 69#if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 70extern void fromhost(); /* get/validate client host info */ 71#else 72#define fromhost sock_host /* no TLI support needed */ 73#endif 74 75extern int hosts_access(); /* access control */ 76extern int hosts_ctl(); /* wrapper around request_init() */ 77extern void shell_cmd(); /* execute shell command */ 78extern char *percent_x(); /* do %<char> expansion */ 79extern void rfc931(); /* client name from RFC 931 daemon */ 80extern void clean_exit(); /* clean up and exit */ 81extern void refuse(); /* clean up and exit */ 82extern char *xgets(); /* fgets() on steroids */ 83extern char *split_at(); /* strchr() and split */ 84extern unsigned long dot_quad_addr(); /* restricted inet_addr() */ 85 86/* Global variables. */ 87 88extern int allow_severity; /* for connection logging */ 89extern int deny_severity; /* for connection logging */ 90extern char *hosts_allow_table; /* for verification mode redirection */ 91extern char *hosts_deny_table; /* for verification mode redirection */ 92extern int hosts_access_verbose; /* for verbose matching mode */ 93extern int rfc931_timeout; /* user lookup timeout */ 94extern int resident; /* > 0 if resident process */ 95 96 /* 97 * Routines for controlled initialization and update of request structure 98 * attributes. Each attribute has its own key. 99 */ 100 101#ifdef __STDC__ 102extern struct request_info *request_init(struct request_info *,...); 103extern struct request_info *request_set(struct request_info *,...); 104#else 105extern struct request_info *request_init(); /* initialize request */ 106extern struct request_info *request_set(); /* update request structure */ 107#endif 108 109#define RQ_FILE 1 /* file descriptor */ 110#define RQ_DAEMON 2 /* server process (argv[0]) */ 111#define RQ_USER 3 /* client user name */ 112#define RQ_CLIENT_NAME 4 /* client host name */ 113#define RQ_CLIENT_ADDR 5 /* client host address */ 114#define RQ_CLIENT_SIN 6 /* client endpoint (internal) */ 115#define RQ_SERVER_NAME 7 /* server host name */ 116#define RQ_SERVER_ADDR 8 /* server host address */ 117#define RQ_SERVER_SIN 9 /* server endpoint (internal) */ 118 119 /* 120 * Routines for delayed evaluation of request attributes. Each attribute 121 * type has its own access method. The trivial ones are implemented by 122 * macros. The other ones are wrappers around the transport-specific host 123 * name, address, and client user lookup methods. The request_info and 124 * host_info structures serve as caches for the lookup results. 125 */ 126 127extern char *eval_user(); /* client user */ 128extern char *eval_hostname(); /* printable hostname */ 129extern char *eval_hostaddr(); /* printable host address */ 130extern char *eval_hostinfo(); /* host name or address */ 131extern char *eval_client(); /* whatever is available */ 132extern char *eval_server(); /* whatever is available */ 133#define eval_daemon(r) ((r)->daemon) /* daemon process name */ 134#define eval_pid(r) ((r)->pid) /* process id */ 135 136/* Socket-specific methods, including DNS hostname lookups. */ 137 138extern void sock_host(); /* look up endpoint addresses */ 139extern void sock_hostname(); /* translate address to hostname */ 140extern void sock_hostaddr(); /* address to printable address */ 141#define sock_methods(r) \ 142 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; } 143 144/* The System V Transport-Level Interface (TLI) interface. */ 145 146#if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 147extern void tli_host(); /* look up endpoint addresses etc. */ 148#endif 149 150 /* 151 * Problem reporting interface. Additional file/line context is reported 152 * when available. The jump buffer (tcpd_buf) is not declared here, or 153 * everyone would have to include <setjmp.h>. 154 */ 155 156#ifdef __STDC__ 157extern void tcpd_warn(char *, ...); /* report problem and proceed */ 158extern void tcpd_jump(char *, ...); /* report problem and jump */ 159#else 160extern void tcpd_warn(); 161extern void tcpd_jump(); 162#endif 163 164struct tcpd_context { 165 char *file; /* current file */ 166 int line; /* current line */ 167}; 168extern struct tcpd_context tcpd_context; 169 170 /* 171 * While processing access control rules, error conditions are handled by 172 * jumping back into the hosts_access() routine. This is cleaner than 173 * checking the return value of each and every silly little function. The 174 * (-1) returns are here because zero is already taken by longjmp(). 175 */ 176 177#define AC_PERMIT 1 /* permit access */ 178#define AC_DENY (-1) /* deny_access */ 179#define AC_ERROR AC_DENY /* XXX */ 180 181 /* 182 * In verification mode an option function should just say what it would do, 183 * instead of really doing it. An option function that would not return 184 * should clear the dry_run flag to inform the caller of this unusual 185 * behavior. 186 */ 187 188extern void process_options(); /* execute options */ 189extern int dry_run; /* verification flag */ 190 191/* Bug workarounds. */ 192 193#ifdef INET_ADDR_BUG /* inet_addr() returns struct */ 194#define inet_addr fix_inet_addr 195extern long fix_inet_addr(); 196#endif 197 198#ifdef BROKEN_FGETS /* partial reads from sockets */ 199#define fgets fix_fgets 200extern char *fix_fgets(); 201#endif 202 203#ifdef RECVFROM_BUG /* no address family info */ 204#define recvfrom fix_recvfrom 205extern int fix_recvfrom(); 206#endif 207 208#ifdef GETPEERNAME_BUG /* claims success with UDP */ 209#define getpeername fix_getpeername 210extern int fix_getpeername(); 211#endif 212 213#ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ 214#define gethostbyname fix_gethostbyname 215extern struct hostent *fix_gethostbyname(); 216#endif 217 218#ifdef USE_STRSEP /* libc calls strtok() */ 219#define strtok fix_strtok 220extern char *fix_strtok(); 221#endif 222 223#ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ 224#define strtok my_strtok 225extern char *my_strtok(); 226#endif 227