tcpd.h revision 1.9 1 /* $NetBSD: tcpd.h,v 1.9 2000/02/05 19:14:57 danw Exp $ */
2 /*
3 * @(#) tcpd.h 1.5 96/03/19 16:22:24
4 *
5 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
6 */
7
8 #include <stdio.h>
9
10 /* Structure to describe one communications endpoint. */
11
12 #define STRING_LENGTH 128 /* hosts, users, processes */
13
14 struct host_info {
15 char name[STRING_LENGTH]; /* access via eval_hostname(host) */
16 char addr[STRING_LENGTH]; /* access via eval_hostaddr(host) */
17 struct sockaddr *sin; /* socket address or 0 */
18 struct t_unitdata *unit; /* TLI transport address or 0 */
19 struct request_info *request; /* for shared information */
20 };
21
22 /* Structure to describe what we know about a service request. */
23
24 struct request_info {
25 int fd; /* socket handle */
26 char user[STRING_LENGTH]; /* access via eval_user(request) */
27 char daemon[STRING_LENGTH]; /* access via eval_daemon(request) */
28 char pid[10]; /* access via eval_pid(request) */
29 struct host_info client[1]; /* client endpoint info */
30 struct host_info server[1]; /* server endpoint info */
31 void (*sink) /* datagram sink function or 0 */
32 __P((int));
33 void (*hostname) /* address to printable hostname */
34 __P((struct host_info *));
35 void (*hostaddr) /* address to printable address */
36 __P((struct host_info *));
37 void (*cleanup) /* cleanup function or 0 */
38 __P((void));
39 struct netconfig *config; /* netdir handle */
40 };
41
42 /* Common string operations. Less clutter should be more readable. */
43
44 #define STRN_CPY(d,s,l) { strncpy((d),(s),(l)); (d)[(l)-1] = 0; }
45
46 #define STRN_EQ(x,y,l) (strncasecmp((x),(y),(l)) == 0)
47 #define STRN_NE(x,y,l) (strncasecmp((x),(y),(l)) != 0)
48 #define STR_EQ(x,y) (strcasecmp((x),(y)) == 0)
49 #define STR_NE(x,y) (strcasecmp((x),(y)) != 0)
50
51 /*
52 * Initially, all above strings have the empty value. Information that
53 * cannot be determined at runtime is set to "unknown", so that we can
54 * distinguish between `unavailable' and `not yet looked up'. A hostname
55 * that we do not believe in is set to "paranoid".
56 */
57
58 #define STRING_UNKNOWN "unknown" /* lookup failed */
59 #define STRING_PARANOID "paranoid" /* hostname conflict */
60
61 extern char unknown[];
62 extern char paranoid[];
63
64 #define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid))
65
66 #define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0)
67
68 /* Global functions. */
69
70 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT)
71 extern void fromhost /* get/validate client host info */
72 __P((struct request_info *));
73 #else
74 #define fromhost sock_host /* no TLI support needed */
75 #endif
76
77 extern int hosts_access /* access control */
78 __P((struct request_info *));
79 extern int hosts_ctl /* limited interface to hosts_access */
80 __P((char *, char *, char *, char *));
81 extern void shell_cmd /* execute shell command */
82 __P((char *));
83 extern char *percent_x /* do %<char> expansion */
84 __P((char *, int, char *, struct request_info *));
85 extern void rfc931 /* client name from RFC 931 daemon */
86 __P((struct sockaddr *, struct sockaddr *, char *));
87 extern void clean_exit /* clean up and exit */
88 __P((struct request_info *));
89 extern void refuse /* clean up and exit */
90 __P((struct request_info *));
91 extern char *xgets /* fgets() on steroids */
92 __P((char *, int, FILE *));
93 extern char *split_at /* strchr() and split */
94 __P((char *, int));
95 extern int dot_quad_addr /* restricted inet_aton() */
96 __P((char *, unsigned long *));
97
98 /* Global variables. */
99
100 extern int allow_severity; /* for connection logging */
101 extern int deny_severity; /* for connection logging */
102 extern char *hosts_allow_table; /* for verification mode redirection */
103 extern char *hosts_deny_table; /* for verification mode redirection */
104 extern int hosts_access_verbose; /* for verbose matching mode */
105 extern int rfc931_timeout; /* user lookup timeout */
106 extern int resident; /* > 0 if resident process */
107
108 /*
109 * Routines for controlled initialization and update of request structure
110 * attributes. Each attribute has its own key.
111 */
112
113 extern struct request_info *request_init /* initialize request */
114 __P((struct request_info *,...));
115 extern struct request_info *request_set /* update request structure */
116 __P((struct request_info *,...));
117
118 #define RQ_FILE 1 /* file descriptor */
119 #define RQ_DAEMON 2 /* server process (argv[0]) */
120 #define RQ_USER 3 /* client user name */
121 #define RQ_CLIENT_NAME 4 /* client host name */
122 #define RQ_CLIENT_ADDR 5 /* client host address */
123 #define RQ_CLIENT_SIN 6 /* client endpoint (internal) */
124 #define RQ_SERVER_NAME 7 /* server host name */
125 #define RQ_SERVER_ADDR 8 /* server host address */
126 #define RQ_SERVER_SIN 9 /* server endpoint (internal) */
127
128 /*
129 * Routines for delayed evaluation of request attributes. Each attribute
130 * type has its own access method. The trivial ones are implemented by
131 * macros. The other ones are wrappers around the transport-specific host
132 * name, address, and client user lookup methods. The request_info and
133 * host_info structures serve as caches for the lookup results.
134 */
135
136 extern char *eval_user /* client user */
137 __P((struct request_info *));
138 extern char *eval_hostname /* printable hostname */
139 __P((struct host_info *));
140 extern char *eval_hostaddr /* printable host address */
141 __P((struct host_info *));
142 extern char *eval_hostinfo /* host name or address */
143 __P((struct host_info *));
144 extern char *eval_client /* whatever is available */
145 __P((struct request_info *));
146 extern char *eval_server /* whatever is available */
147 __P((struct request_info *));
148 #define eval_daemon(r) ((r)->daemon) /* daemon process name */
149 #define eval_pid(r) ((r)->pid) /* process id */
150
151 /* Socket-specific methods, including DNS hostname lookups. */
152
153 extern void sock_host /* look up endpoint addresses */
154 __P((struct request_info *));
155 extern void sock_hostname /* translate address to hostname */
156 __P((struct host_info *));
157 extern void sock_hostaddr /* address to printable address */
158 __P((struct host_info *));
159 #define sock_methods(r) \
160 { (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; }
161
162 /* The System V Transport-Level Interface (TLI) interface. */
163
164 #if defined(TLI) || defined(PTX) || defined(TLI_SEQUENT)
165 extern void tli_host /* look up endpoint addresses etc. */
166 __P((struct request_info *));
167 #endif
168
169 /*
170 * Problem reporting interface. Additional file/line context is reported
171 * when available. The jump buffer (tcpd_buf) is not declared here, or
172 * everyone would have to include <setjmp.h>.
173 */
174
175 extern void tcpd_warn /* report problem and proceed */
176 __P((char *, ...));
177 extern void tcpd_jump /* report problem and jump */
178 __P((char *, ...));
179
180 struct tcpd_context {
181 char *file; /* current file */
182 int line; /* current line */
183 };
184 extern struct tcpd_context tcpd_context;
185
186 /*
187 * While processing access control rules, error conditions are handled by
188 * jumping back into the hosts_access() routine. This is cleaner than
189 * checking the return value of each and every silly little function. The
190 * (-1) returns are here because zero is already taken by longjmp().
191 */
192
193 #define AC_PERMIT 1 /* permit access */
194 #define AC_DENY (-1) /* deny_access */
195 #define AC_ERROR AC_DENY /* XXX */
196
197 /*
198 * In verification mode an option function should just say what it would do,
199 * instead of really doing it. An option function that would not return
200 * should clear the dry_run flag to inform the caller of this unusual
201 * behavior.
202 */
203
204 extern void process_options /* execute options */
205 __P((char *, struct request_info *));
206 extern int dry_run; /* verification flag */
207 extern void fix_options /* get rid of IP-level socket options */
208 __P((struct request_info *));
209 /* Bug workarounds. */
210
211 #ifdef INET_ADDR_BUG /* inet_addr() returns struct */
212 #define inet_addr fix_inet_addr
213 extern long fix_inet_addr __P((char *));
214 #endif
215
216 #ifdef BROKEN_FGETS /* partial reads from sockets */
217 #define fgets fix_fgets
218 extern char *fix_fgets __P((char *, int, FILE *));
219 #endif
220
221 #ifdef RECVFROM_BUG /* no address family info */
222 #define recvfrom fix_recvfrom
223 extern int fix_recvfrom __P((int, char *, int, int, struct sockaddr *, int *));
224 #endif
225
226 #ifdef GETPEERNAME_BUG /* claims success with UDP */
227 #include <sys/socket.h> /* XXX serious hack! */
228 #define getpeername fix_getpeername
229 extern int fix_getpeername __P((int, struct sockaddr *, int *));
230 #endif
231
232 #ifdef SOLARIS_24_GETHOSTBYNAME_BUG /* lists addresses as aliases */
233 #define gethostbyname fix_gethostbyname
234 extern struct hostent *fix_gethostbyname __P((char *));
235 #endif
236
237 #ifdef USE_STRSEP /* libc calls strtok() */
238 #define strtok fix_strtok
239 extern char *fix_strtok __P((char *, char *));
240 #endif
241
242 #ifdef LIBC_CALLS_STRTOK /* libc calls strtok() */
243 #define strtok my_strtok
244 extern char *my_strtok __P((char *, char *));
245 #endif
246