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 * $FreeBSD$ 7 */ 8 9 /* Structure to describe one communications endpoint. */ 10 11 #define STRING_LENGTH 128 /* hosts, users, processes */ 12 13 struct 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 27 struct 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) (); /* datagram sink function or 0 */ 35 void (*hostname) (); /* address to printable hostname */ 36 void (*hostaddr) (); /* address to printable address */ 37 void (*cleanup) (); /* 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 60 extern char unknown[]; 61 extern 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) 70 extern void fromhost(); /* get/validate client host info */ 71 #else 72 #define fromhost sock_host /* no TLI support needed */ 73 #endif 74 75 extern int hosts_access(); /* access control */ 76 extern void shell_cmd(); /* execute shell command */ 77 extern char *percent_x(); /* do %<char> expansion */ 78 extern void rfc931(); /* client name from RFC 931 daemon */ 79 extern void clean_exit(); /* clean up and exit */ 80 extern void refuse(); /* clean up and exit */ 81 extern char *xgets(); /* fgets() on steroids */ 82 extern char *split_at(); /* strchr() and split */ 83 extern unsigned long dot_quad_addr(); /* restricted inet_addr() */ 84 85 /* Global variables. */ 86 87 extern int allow_severity; /* for connection logging */ 88 extern int deny_severity; /* for connection logging */ 89 extern char *hosts_allow_table; /* for verification mode redirection */ 90 extern char *hosts_deny_table; /* for verification mode redirection */ 91 extern int hosts_access_verbose; /* for verbose matching mode */ 92 extern int rfc931_timeout; /* user lookup timeout */ 93 extern int resident; /* > 0 if resident process */ 94 95 /* 96 * Routines for controlled initialization and update of request structure 97 * attributes. Each attribute has its own key. 98 */ 99 100 #ifdef __STDC__ 101 extern struct request_info *request_init(struct request_info *,...); 102 extern struct request_info *request_set(struct request_info *,...); 103 #else 104 extern struct request_info *request_init(); /* initialize request */ 105 extern struct request_info *request_set(); /* update request structure */ 106 #endif 107 108 #define RQ_FILE 1 /* file descriptor */ 109 #define RQ_DAEMON 2 /* server process (argv[0]) */ 110 #define RQ_USER 3 /* client user name */ 111 #define RQ_CLIENT_NAME 4 /* client host name */ 112 #define RQ_CLIENT_ADDR 5 /* client host address */ 113 #define RQ_CLIENT_SIN 6 /* client endpoint (internal) */ 114 #define RQ_SERVER_NAME 7 /* server host name */ 115 #define RQ_SERVER_ADDR 8 /* server host address */ 116 #define RQ_SERVER_SIN 9 /* server endpoint (internal) */ 117 118 /* 119 * Routines for delayed evaluation of request attributes. Each attribute 120 * type has its own access method. The trivial ones are implemented by 121 * macros. The other ones are wrappers around the transport-specific host 122 * name, address, and client user lookup methods. The request_info and 123 * host_info structures serve as caches for the lookup results. 124 */ 125 126 extern char *eval_user(); /* client user */ 127 extern char *eval_hostname(); /* printable hostname */ 128 extern char *eval_hostaddr(); /* printable host address */ 129 extern char *eval_hostinfo(); /* host name or address */ 130 extern char *eval_client(); /* whatever is available */ 131 extern char *eval_server(); /* whatever is available */ 132 #define eval_daemon(r) ((r)->daemon) /* daemon process name */ 133 #define eval_pid(r) ((r)->pid) /* process id */ 134 135 /* Socket-specific methods, including DNS hostname lookups. */ 136 137 extern void sock_host(); /* look up endpoint addresses */ 138 extern void sock_hostname(); /* translate address to hostname */ 139 extern void sock_hostaddr(); /* address to printable address */ 140 #define sock_methods(r) \ 141 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; } 142 143 /* The System V Transport-Level Interface (TLI) interface. */ 144 145 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT) 146 extern void tli_host(); /* look up endpoint addresses etc. */ 147 #endif 148 149 /* 150 * Problem reporting interface. Additional file/line context is reported 151 * when available. The jump buffer (tcpd_buf) is not declared here, or 152 * everyone would have to include <setjmp.h>. 153 */ 154 155 #ifdef __STDC__ 156 extern void tcpd_warn(char *, ...); /* report problem and proceed */ 157 extern void tcpd_jump(char *, ...); /* report problem and jump */ 158 #else 159 extern void tcpd_warn(); 160 extern void tcpd_jump(); 161 #endif 162 163 struct tcpd_context { 164 char *file; /* current file */ 165 int line; /* current line */ 166 }; 167 extern struct tcpd_context tcpd_context; 168 169 /* 170 * While processing access control rules, error conditions are handled by 171 * jumping back into the hosts_access() routine. This is cleaner than 172 * checking the return value of each and every silly little function. The 173 * (-1) returns are here because zero is already taken by longjmp(). 174 */ 175 176 #define AC_PERMIT 1 /* permit access */ 177 #define AC_DENY (-1) /* deny_access */ 178 #define AC_ERROR AC_DENY /* XXX */ 179 180 /* 181 * In verification mode an option function should just say what it would do, 182 * instead of really doing it. An option function that would not return 183 * should clear the dry_run flag to inform the caller of this unusual 184 * behavior. 185 */ 186 187 extern void process_options(); /* execute options */ 188 extern int dry_run; /* verification flag */ 189 190 /* Bug workarounds. */ 191 192 #ifdef INET_ADDR_BUG /* inet_addr() returns struct */ 193 #define inet_addr fix_inet_addr 194 extern long fix_inet_addr(); 195 #endif 196 197 #ifdef BROKEN_FGETS /* partial reads from sockets */ 198 #define fgets fix_fgets 199 extern char *fix_fgets(); 200 #endif 201 202 #ifdef RECVFROM_BUG /* no address family info */ 203 #define recvfrom fix_recvfrom 204 extern int fix_recvfrom(); 205 #endif 206 207 #ifdef GETPEERNAME_BUG /* claims success with UDP */ 208 #define getpeername fix_getpeername 209 extern int fix_getpeername(); 210 #endif 211 212 #ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */ 213 #define gethostbyname fix_gethostbyname 214 extern struct hostent *fix_gethostbyname(); 215 #endif 216 217 #ifdef USE_STRSEP /* libc calls strtok() */ 218 #define strtok fix_strtok 219 extern char *fix_strtok(); 220 #endif 221 222 #ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */ 223 #define strtok my_strtok 224 extern char *my_strtok(); 225 #endif 226