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: src/contrib/tcp_wrappers/tcpd.h,v 1.2 2000/02/03 10:26:59 shin Exp $ 7 * $DragonFly: src/contrib/tcp_wrappers/tcpd.h,v 1.4 2005/09/15 04:34:52 sephe Exp $ 8 */ 9 10 #ifndef _LIBWRAP_TCPD_H 11 #define _LIBWRAP_TCPD_H 12 13 #include <sys/cdefs.h> 14 #include <stdio.h> 15 16 /* Structure to describe one communications endpoint. */ 17 18 #define STRING_LENGTH 128 /* hosts, users, processes */ 19 20 struct host_info { 21 char name[STRING_LENGTH]; /* access via eval_hostname(host) */ 22 char addr[STRING_LENGTH]; /* access via eval_hostaddr(host) */ 23 #ifdef INET6 24 struct sockaddr *sin; /* socket address or 0 */ 25 #else 26 struct sockaddr_in *sin; /* socket address or 0 */ 27 #endif 28 struct t_unitdata *unit; /* TLI transport address or 0 */ 29 struct request_info *request; /* for shared information */ 30 }; 31 32 /* Structure to describe what we know about a service request. */ 33 34 struct request_info { 35 int fd; /* socket handle */ 36 char user[STRING_LENGTH]; /* access via eval_user(request) */ 37 char daemon[STRING_LENGTH]; /* access via eval_daemon(request) */ 38 char pid[10]; /* access via eval_pid(request) */ 39 struct host_info client[1]; /* client endpoint info */ 40 struct host_info server[1]; /* server endpoint info */ 41 void (*sink) (int); /* datagram sink function or 0 */ 42 void (*hostname) /* address to printable hostname */ 43 (struct host_info *); 44 void (*hostaddr) /* address to printable address */ 45 (struct host_info *); 46 void (*cleanup) (void); /* cleanup function or 0 */ 47 struct netconfig *config; /* netdir handle */ 48 }; 49 50 /* Common string operations. Less clutter should be more readable. */ 51 52 #define STRN_CPY(d,s,l) { strncpy((d),(s),(l)); (d)[(l)-1] = 0; } 53 54 #define STRN_EQ(x,y,l) (strncasecmp((x),(y),(l)) == 0) 55 #define STRN_NE(x,y,l) (strncasecmp((x),(y),(l)) != 0) 56 #define STR_EQ(x,y) (strcasecmp((x),(y)) == 0) 57 #define STR_NE(x,y) (strcasecmp((x),(y)) != 0) 58 59 /* 60 * Initially, all above strings have the empty value. Information that 61 * cannot be determined at runtime is set to "unknown", so that we can 62 * distinguish between `unavailable' and `not yet looked up'. A hostname 63 * that we do not believe in is set to "paranoid". 64 */ 65 66 #define STRING_UNKNOWN "unknown" /* lookup failed */ 67 #define STRING_PARANOID "paranoid" /* hostname conflict */ 68 69 __BEGIN_DECLS 70 extern char unknown[]; 71 extern char paranoid[]; 72 __END_DECLS 73 74 #define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid)) 75 76 #define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0) 77 78 /* Global functions. */ 79 80 __BEGIN_DECLS 81 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 82 extern void fromhost(); /* get/validate client host info */ 83 #else 84 #define fromhost sock_host /* no TLI support needed */ 85 #endif 86 87 int hosts_access(struct request_info *);/* access control */ 88 void shell_cmd(char *); /* execute shell command */ 89 char *percent_x(char *, int, char *, struct request_info *);/* do %<char> expansion */ 90 void rfc931(struct sockaddr *, struct sockaddr *, char *);/* client name from RFC 931 daemon */ 91 void clean_exit(struct request_info *);/* clean up and exit */ 92 void refuse(struct request_info *); /* clean up and exit */ 93 char *xgets(char *, int, FILE *); /* fgets() on steroids */ 94 char *split_at(char *, int); /* strchr() and split */ 95 unsigned long dot_quad_addr(char *); /* restricted inet_addr() */ 96 97 /* Global variables. */ 98 99 extern int allow_severity; /* for connection logging */ 100 extern int deny_severity; /* for connection logging */ 101 extern char *hosts_allow_table; /* for verification mode redirection */ 102 extern char *hosts_deny_table; /* for verification mode redirection */ 103 extern int hosts_access_verbose; /* for verbose matching mode */ 104 extern int rfc931_timeout; /* user lookup timeout */ 105 extern int resident; /* > 0 if resident process */ 106 107 /* 108 * Routines for controlled initialization and update of request structure 109 * attributes. Each attribute has its own key. 110 */ 111 112 struct request_info *request_init(struct request_info *,...);/* initialize request */ 113 struct request_info *request_set(struct request_info *,...);/* update request structure */ 114 115 #define RQ_FILE 1 /* file descriptor */ 116 #define RQ_DAEMON 2 /* server process (argv[0]) */ 117 #define RQ_USER 3 /* client user name */ 118 #define RQ_CLIENT_NAME 4 /* client host name */ 119 #define RQ_CLIENT_ADDR 5 /* client host address */ 120 #define RQ_CLIENT_SIN 6 /* client endpoint (internal) */ 121 #define RQ_SERVER_NAME 7 /* server host name */ 122 #define RQ_SERVER_ADDR 8 /* server host address */ 123 #define RQ_SERVER_SIN 9 /* server endpoint (internal) */ 124 125 /* 126 * Routines for delayed evaluation of request attributes. Each attribute 127 * type has its own access method. The trivial ones are implemented by 128 * macros. The other ones are wrappers around the transport-specific host 129 * name, address, and client user lookup methods. The request_info and 130 * host_info structures serve as caches for the lookup results. 131 */ 132 133 char *eval_user(struct request_info *); /* client user */ 134 char *eval_hostname(struct host_info *); /* printable hostname */ 135 char *eval_hostaddr(struct host_info *); /* printable host address */ 136 char *eval_hostinfo(struct host_info *); /* host name or address */ 137 char *eval_client(struct request_info *); /* whatever is available */ 138 char *eval_server(struct request_info *); /* whatever is available */ 139 #define eval_daemon(r) ((r)->daemon) /* daemon process name */ 140 #define eval_pid(r) ((r)->pid) /* process id */ 141 142 /* Socket-specific methods, including DNS hostname lookups. */ 143 144 void sock_host(struct request_info *); /* look up endpoint addresses */ 145 void sock_hostname(struct host_info *); /* translate address to hostname */ 146 void sock_hostaddr(struct host_info *); /* address to printable address */ 147 #define sock_methods(r) \ 148 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; } 149 150 /* The System V Transport-Level Interface (TLI) interface. */ 151 152 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 153 extern void tli_host(); /* look up endpoint addresses etc. */ 154 #endif 155 156 /* 157 * Problem reporting interface. Additional file/line context is reported 158 * when available. The jump buffer (tcpd_buf) is not declared here, or 159 * everyone would have to include <setjmp.h>. 160 */ 161 162 void tcpd_warn(const char *, ...) __printflike(1, 2);/* report problem and proceed */ 163 void tcpd_jump(const char *, ...) __printflike(1, 2);/* report problem and jump */ 164 __END_DECLS 165 166 struct tcpd_context { 167 char *file; /* current file */ 168 int line; /* current line */ 169 }; 170 __BEGIN_DECLS 171 extern struct tcpd_context tcpd_context; 172 __END_DECLS 173 174 /* 175 * While processing access control rules, error conditions are handled by 176 * jumping back into the hosts_access() routine. This is cleaner than 177 * checking the return value of each and every silly little function. The 178 * (-1) returns are here because zero is already taken by longjmp(). 179 */ 180 181 #define AC_PERMIT 1 /* permit access */ 182 #define AC_DENY (-1) /* deny_access */ 183 #define AC_ERROR AC_DENY /* XXX */ 184 185 /* 186 * In verification mode an option function should just say what it would do, 187 * instead of really doing it. An option function that would not return 188 * should clear the dry_run flag to inform the caller of this unusual 189 * behavior. 190 */ 191 192 __BEGIN_DECLS 193 void process_options(char *, struct request_info *); /* execute options */ 194 extern int dry_run; /* verification flag */ 195 196 /* Bug workarounds. */ 197 198 #ifdef INET_ADDR_BUG /* inet_addr() returns struct */ 199 #define inet_addr fix_inet_addr 200 extern long fix_inet_addr(); 201 #endif 202 203 #ifdef BROKEN_FGETS /* partial reads from sockets */ 204 #define fgets fix_fgets 205 extern char *fix_fgets(); 206 #endif 207 208 #ifdef RECVFROM_BUG /* no address family info */ 209 #define recvfrom fix_recvfrom 210 extern int fix_recvfrom(); 211 #endif 212 213 #ifdef GETPEERNAME_BUG /* claims success with UDP */ 214 #define getpeername fix_getpeername 215 extern int fix_getpeername(); 216 #endif 217 218 #ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ 219 #define gethostbyname fix_gethostbyname 220 extern struct hostent *fix_gethostbyname(); 221 #endif 222 223 #ifdef USE_STRSEP /* libc calls strtok() */ 224 #define strtok fix_strtok 225 extern char *fix_strtok(); 226 #endif 227 228 #ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ 229 #define strtok my_strtok 230 extern char *my_strtok(); 231 #endif 232 __END_DECLS 233 234 #endif /* !_LIBWRAP_TCPD_H */ 235