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 1.3 2005/09/04 01:53:07 sephe Exp $ 8 */ 9 10 #ifndef _LIBWRAP_TCPD_H 11 #define _LIBWRAP_TCPD_H 12 13 #include <sys/cdefs.h> 14 15 /* Structure to describe one communications endpoint. */ 16 17 #define STRING_LENGTH 128 /* hosts, users, processes */ 18 19 struct host_info { 20 char name[STRING_LENGTH]; /* access via eval_hostname(host) */ 21 char addr[STRING_LENGTH]; /* access via eval_hostaddr(host) */ 22 #ifdef INET6 23 struct sockaddr *sin; /* socket address or 0 */ 24 #else 25 struct sockaddr_in *sin; /* socket address or 0 */ 26 #endif 27 struct t_unitdata *unit; /* TLI transport address or 0 */ 28 struct request_info *request; /* for shared information */ 29 }; 30 31 /* Structure to describe what we know about a service request. */ 32 33 struct request_info { 34 int fd; /* socket handle */ 35 char user[STRING_LENGTH]; /* access via eval_user(request) */ 36 char daemon[STRING_LENGTH]; /* access via eval_daemon(request) */ 37 char pid[10]; /* access via eval_pid(request) */ 38 struct host_info client[1]; /* client endpoint info */ 39 struct host_info server[1]; /* server endpoint info */ 40 void (*sink) (int); /* datagram sink function or 0 */ 41 void (*hostname) /* address to printable hostname */ 42 (struct host_info *); 43 void (*hostaddr) /* address to printable address */ 44 (struct host_info *); 45 void (*cleanup) (void); /* cleanup function or 0 */ 46 struct netconfig *config; /* netdir handle */ 47 }; 48 49 /* Common string operations. Less clutter should be more readable. */ 50 51 #define STRN_CPY(d,s,l) { strncpy((d),(s),(l)); (d)[(l)-1] = 0; } 52 53 #define STRN_EQ(x,y,l) (strncasecmp((x),(y),(l)) == 0) 54 #define STRN_NE(x,y,l) (strncasecmp((x),(y),(l)) != 0) 55 #define STR_EQ(x,y) (strcasecmp((x),(y)) == 0) 56 #define STR_NE(x,y) (strcasecmp((x),(y)) != 0) 57 58 /* 59 * Initially, all above strings have the empty value. Information that 60 * cannot be determined at runtime is set to "unknown", so that we can 61 * distinguish between `unavailable' and `not yet looked up'. A hostname 62 * that we do not believe in is set to "paranoid". 63 */ 64 65 #define STRING_UNKNOWN "unknown" /* lookup failed */ 66 #define STRING_PARANOID "paranoid" /* hostname conflict */ 67 68 __BEGIN_DECLS 69 extern char unknown[]; 70 extern char paranoid[]; 71 __END_DECLS 72 73 #define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid)) 74 75 #define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0) 76 77 /* Global functions. */ 78 79 __BEGIN_DECLS 80 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 81 extern void fromhost(); /* get/validate client host info */ 82 #else 83 #define fromhost sock_host /* no TLI support needed */ 84 #endif 85 86 int hosts_access(struct request_info *);/* access control */ 87 void shell_cmd(char *); /* execute shell command */ 88 char *percent_x(char *, int, char *, struct request_info *);/* do %<char> expansion */ 89 void rfc931(struct sockaddr *, struct sockaddr *, char *);/* client name from RFC 931 daemon */ 90 void clean_exit(struct request_info *);/* clean up and exit */ 91 void refuse(struct request_info *); /* clean up and exit */ 92 char *xgets(char *, int, FILE *); /* fgets() on steroids */ 93 char *split_at(char *, int); /* strchr() and split */ 94 unsigned long dot_quad_addr(char *); /* restricted inet_addr() */ 95 96 /* Global variables. */ 97 98 extern int allow_severity; /* for connection logging */ 99 extern int deny_severity; /* for connection logging */ 100 extern char *hosts_allow_table; /* for verification mode redirection */ 101 extern char *hosts_deny_table; /* for verification mode redirection */ 102 extern int hosts_access_verbose; /* for verbose matching mode */ 103 extern int rfc931_timeout; /* user lookup timeout */ 104 extern int resident; /* > 0 if resident process */ 105 106 /* 107 * Routines for controlled initialization and update of request structure 108 * attributes. Each attribute has its own key. 109 */ 110 111 struct request_info *request_init(struct request_info *,...);/* initialize request */ 112 struct request_info *request_set(struct request_info *,...);/* update request structure */ 113 114 #define RQ_FILE 1 /* file descriptor */ 115 #define RQ_DAEMON 2 /* server process (argv[0]) */ 116 #define RQ_USER 3 /* client user name */ 117 #define RQ_CLIENT_NAME 4 /* client host name */ 118 #define RQ_CLIENT_ADDR 5 /* client host address */ 119 #define RQ_CLIENT_SIN 6 /* client endpoint (internal) */ 120 #define RQ_SERVER_NAME 7 /* server host name */ 121 #define RQ_SERVER_ADDR 8 /* server host address */ 122 #define RQ_SERVER_SIN 9 /* server endpoint (internal) */ 123 124 /* 125 * Routines for delayed evaluation of request attributes. Each attribute 126 * type has its own access method. The trivial ones are implemented by 127 * macros. The other ones are wrappers around the transport-specific host 128 * name, address, and client user lookup methods. The request_info and 129 * host_info structures serve as caches for the lookup results. 130 */ 131 132 char *eval_user(struct request_info *); /* client user */ 133 char *eval_hostname(struct host_info *); /* printable hostname */ 134 char *eval_hostaddr(struct host_info *); /* printable host address */ 135 char *eval_hostinfo(struct host_info *); /* host name or address */ 136 char *eval_client(struct request_info *); /* whatever is available */ 137 char *eval_server(struct request_info *); /* whatever is available */ 138 #define eval_daemon(r) ((r)->daemon) /* daemon process name */ 139 #define eval_pid(r) ((r)->pid) /* process id */ 140 141 /* Socket-specific methods, including DNS hostname lookups. */ 142 143 void sock_host(struct request_info *); /* look up endpoint addresses */ 144 void sock_hostname(struct host_info *); /* translate address to hostname */ 145 void sock_hostaddr(struct host_info *); /* address to printable address */ 146 #define sock_methods(r) \ 147 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; } 148 149 /* The System V Transport-Level Interface (TLI) interface. */ 150 151 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 152 extern void tli_host(); /* look up endpoint addresses etc. */ 153 #endif 154 155 /* 156 * Problem reporting interface. Additional file/line context is reported 157 * when available. The jump buffer (tcpd_buf) is not declared here, or 158 * everyone would have to include <setjmp.h>. 159 */ 160 161 void tcpd_warn(char *, ...) __printflike(1, 2); /* report problem and proceed */ 162 void tcpd_jump(char *, ...) __printflike(1, 2); /* report problem and jump */ 163 __END_DECLS 164 165 struct tcpd_context { 166 char *file; /* current file */ 167 int line; /* current line */ 168 }; 169 __BEGIN_DECLS 170 extern struct tcpd_context tcpd_context; 171 __END_DECLS 172 173 /* 174 * While processing access control rules, error conditions are handled by 175 * jumping back into the hosts_access() routine. This is cleaner than 176 * checking the return value of each and every silly little function. The 177 * (-1) returns are here because zero is already taken by longjmp(). 178 */ 179 180 #define AC_PERMIT 1 /* permit access */ 181 #define AC_DENY (-1) /* deny_access */ 182 #define AC_ERROR AC_DENY /* XXX */ 183 184 /* 185 * In verification mode an option function should just say what it would do, 186 * instead of really doing it. An option function that would not return 187 * should clear the dry_run flag to inform the caller of this unusual 188 * behavior. 189 */ 190 191 __BEGIN_DECLS 192 void process_options(char *, struct request_info *); /* execute options */ 193 extern int dry_run; /* verification flag */ 194 195 /* Bug workarounds. */ 196 197 #ifdef INET_ADDR_BUG /* inet_addr() returns struct */ 198 #define inet_addr fix_inet_addr 199 extern long fix_inet_addr(); 200 #endif 201 202 #ifdef BROKEN_FGETS /* partial reads from sockets */ 203 #define fgets fix_fgets 204 extern char *fix_fgets(); 205 #endif 206 207 #ifdef RECVFROM_BUG /* no address family info */ 208 #define recvfrom fix_recvfrom 209 extern int fix_recvfrom(); 210 #endif 211 212 #ifdef GETPEERNAME_BUG /* claims success with UDP */ 213 #define getpeername fix_getpeername 214 extern int fix_getpeername(); 215 #endif 216 217 #ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ 218 #define gethostbyname fix_gethostbyname 219 extern struct hostent *fix_gethostbyname(); 220 #endif 221 222 #ifdef USE_STRSEP /* libc calls strtok() */ 223 #define strtok fix_strtok 224 extern char *fix_strtok(); 225 #endif 226 227 #ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ 228 #define strtok my_strtok 229 extern char *my_strtok(); 230 #endif 231 __END_DECLS 232 233 #endif /* !_LIBWRAP_TCPD_H */ 234