1 /*
2 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
3 * Use is subject to license terms.
4 */
5
6 #pragma ident "%Z%%M% %I% %E% SMI"
7
8 /*
9 * tli_host() determines the type of transport (connected, connectionless),
10 * the transport address of a client host, and the transport address of a
11 * server endpoint. In addition, it provides methods to map a transport
12 * address to a printable host name or address. Socket address results are
13 * in static memory; tli structures are allocated from the heap.
14 *
15 * The result from the hostname lookup method is STRING_PARANOID when a host
16 * pretends to have someone elses name, or when a host name is available but
17 * could not be verified.
18 *
19 * Diagnostics are reported through syslog(3).
20 *
21 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
22 */
23
24 #ifndef lint
25 static char sccsid[] = "@(#) tli.c 1.15 97/03/21 19:27:25";
26 #endif
27
28 #ifdef TLI
29
30 /* System libraries. */
31
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/stream.h>
35 #include <sys/stat.h>
36 #include <sys/mkdev.h>
37 #include <sys/tiuser.h>
38 #include <sys/timod.h>
39 #include <sys/socket.h>
40 #include <netinet/in.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <unistd.h>
44 #include <syslog.h>
45 #include <errno.h>
46 #include <netconfig.h>
47 #include <netdir.h>
48 #include <string.h>
49
50 extern char *nc_sperror();
51 extern int errno;
52 extern char *sys_errlist[];
53 extern int sys_nerr;
54 extern int t_errno;
55 extern char *t_errlist[];
56 extern int t_nerr;
57
58 /* Local stuff. */
59
60 #include "tcpd.h"
61
62 /* Forward declarations. */
63
64 static void tli_endpoints();
65 static struct netconfig *tli_transport();
66 static void tli_hostname();
67 static void tli_hostaddr();
68 static void tli_cleanup();
69 static char *tli_error();
70 static void tli_sink();
71
72 /* tli_host - look up endpoint addresses and install conversion methods */
73
74 void tli_host(request)
75 struct request_info *request;
76 {
77 static struct sockaddr_gen client;
78 static struct sockaddr_gen server;
79
80 /*
81 * If we discover that we are using an IP transport, pretend we never
82 * were here. Otherwise, use the transport-independent method and stick
83 * to generic network addresses. XXX hard-coded protocol family name.
84 */
85
86 tli_endpoints(request);
87 if ((request->config = tli_transport(request->fd)) != 0
88 && (STR_EQ(request->config->nc_protofmly, "inet")
89 #ifdef HAVE_IPV6
90 || STR_EQ(request->config->nc_protofmly, "inet6")
91 #endif
92 )) {
93 if (request->client->unit != 0) {
94 memcpy(&client, request->client->unit->addr.buf,
95 SGSOCKADDRSZ((struct sockaddr_gen*)
96 request->client->unit->addr.buf));
97 request->client->sin = &client;
98 sockgen_simplify(&client);
99 }
100 if (request->server->unit != 0) {
101 memcpy(&server, request->server->unit->addr.buf,
102 SGSOCKADDRSZ((struct sockaddr_gen*)
103 request->server->unit->addr.buf));
104 request->server->sin = &server;
105 sockgen_simplify(&server);
106 }
107 tli_cleanup(request);
108 sock_methods(request);
109 } else {
110 request->hostname = tli_hostname;
111 request->hostaddr = tli_hostaddr;
112 request->cleanup = tli_cleanup;
113 }
114 }
115
116 /* tli_cleanup - cleanup some dynamically-allocated data structures */
117
118 static void tli_cleanup(request)
119 struct request_info *request;
120 {
121 if (request->config != 0)
122 freenetconfigent(request->config);
123 if (request->client->unit != 0)
124 t_free((char *) request->client->unit, T_UNITDATA);
125 if (request->server->unit != 0)
126 t_free((char *) request->server->unit, T_UNITDATA);
127 }
128
129 /* tli_endpoints - determine TLI client and server endpoint information */
130
131 static void tli_endpoints(request)
132 struct request_info *request;
133 {
134 struct t_unitdata *server;
135 struct t_unitdata *client;
136 int fd = request->fd;
137 int flags;
138
139 /*
140 * Determine the client endpoint address. With unconnected services, peek
141 * at the sender address of the pending protocol data unit without
142 * popping it off the receive queue. This trick works because only the
143 * address member of the unitdata structure has been allocated.
144 *
145 * Beware of successful returns with zero-length netbufs (for example,
146 * Solaris 2.3 with ticlts transport). The netdir(3) routines can't
147 * handle that. Assume connection-less transport when TI_GETPEERNAME
148 * produces no usable result, even when t_rcvudata() is unable to figure
149 * out the peer address. Better to hang than to loop.
150 */
151
152 if ((client = (struct t_unitdata *) t_alloc(fd, T_UNITDATA, T_ADDR)) == 0) {
153 tcpd_warn("t_alloc: %s", tli_error());
154 return;
155 }
156 if (ioctl(fd, TI_GETPEERNAME, &client->addr) < 0 || client->addr.len == 0) {
157 request->sink = tli_sink;
158 if (t_rcvudata(fd, client, &flags) < 0 || client->addr.len == 0) {
159 tcpd_warn("can't get client address: %s", tli_error());
160 t_free((void *) client, T_UNITDATA);
161 return;
162 }
163 }
164 request->client->unit = client;
165
166 /*
167 * Look up the server endpoint address. This can be used for filtering on
168 * server address or name, or to look up the client user.
169 */
170
171 if ((server = (struct t_unitdata *) t_alloc(fd, T_UNITDATA, T_ADDR)) == 0) {
172 tcpd_warn("t_alloc: %s", tli_error());
173 return;
174 }
175 if (ioctl(fd, TI_GETMYNAME, &server->addr) < 0) {
176 tcpd_warn("TI_GETMYNAME: %m");
177 t_free((void *) server, T_UNITDATA);
178 return;
179 }
180 request->server->unit = server;
181 }
182
183 /* tli_transport - find out TLI transport type */
184
185 static struct netconfig *tli_transport(fd)
186 int fd;
187 {
188 struct stat from_client;
189 struct stat from_config;
190 void *handlep;
191 struct netconfig *config;
192
193 /*
194 * Assuming that the network device is a clone device, we must compare
195 * the major device number of stdin to the minor device number of the
196 * devices listed in the netconfig table.
197 */
198
199 if (fstat(fd, &from_client) != 0) {
200 tcpd_warn("fstat(fd %d): %m", fd);
201 return (0);
202 }
203 if ((handlep = setnetconfig()) == 0) {
204 tcpd_warn("setnetconfig: %m");
205 return (0);
206 }
207 while (config = getnetconfig(handlep)) {
208 if (stat(config->nc_device, &from_config) == 0) {
209 if (minor(from_config.st_rdev) == major(from_client.st_rdev) ||
210 /* XXX: Solaris 8 no longer has clone devices for IP */
211 major(from_config.st_rdev) == major(from_client.st_rdev))
212 break;
213 }
214 }
215 if (config == 0) {
216 tcpd_warn("unable to identify transport protocol");
217 return (0);
218 }
219
220 /*
221 * Something else may clobber our getnetconfig() result, so we'd better
222 * acquire our private copy.
223 */
224
225 if ((config = getnetconfigent(config->nc_netid)) == 0) {
226 tcpd_warn("getnetconfigent(%s): %s", config->nc_netid, nc_sperror());
227 return (0);
228 }
229 return (config);
230 }
231
232 /* tli_hostaddr - map TLI transport address to printable address */
233
234 static void tli_hostaddr(host)
235 struct host_info *host;
236 {
237 struct request_info *request = host->request;
238 struct netconfig *config = request->config;
239 struct t_unitdata *unit = host->unit;
240 char *uaddr;
241
242 if (config != 0 && unit != 0
243 && (uaddr = taddr2uaddr(config, &unit->addr)) != 0) {
244 STRN_CPY(host->addr, uaddr, sizeof(host->addr));
245 free(uaddr);
246 }
247 }
248
249 /* tli_hostname - map TLI transport address to hostname */
250
251 static void tli_hostname(host)
252 struct host_info *host;
253 {
254 struct request_info *request = host->request;
255 struct netconfig *config = request->config;
256 struct t_unitdata *unit = host->unit;
257 struct nd_hostservlist *servlist;
258
259 if (config != 0 && unit != 0
260 && netdir_getbyaddr(config, &servlist, &unit->addr) == ND_OK) {
261
262 struct nd_hostserv *service = servlist->h_hostservs;
263 struct nd_addrlist *addr_list;
264 int found = 0;
265
266 if (netdir_getbyname(config, service, &addr_list) != ND_OK) {
267
268 /*
269 * Unable to verify that the name matches the address. This may
270 * be a transient problem or a botched name server setup. We
271 * decide to play safe.
272 */
273
274 tcpd_warn("can't verify hostname: netdir_getbyname(%.*s) failed",
275 STRING_LENGTH, service->h_host);
276
277 } else {
278
279 /*
280 * Look up the host address in the address list we just got. The
281 * comparison is done on the textual representation, because the
282 * transport address is an opaque structure that may have holes
283 * with uninitialized garbage. This approach obviously loses when
284 * the address does not have a textual representation.
285 */
286
287 char *uaddr = eval_hostaddr(host);
288 char *ua;
289 int i;
290
291 for (i = 0; found == 0 && i < addr_list->n_cnt; i++) {
292 if ((ua = taddr2uaddr(config, &(addr_list->n_addrs[i]))) != 0) {
293 found = !strcmp(ua, uaddr);
294 free(ua);
295 }
296 }
297 netdir_free((void *) addr_list, ND_ADDRLIST);
298
299 /*
300 * When the host name does not map to the initial address, assume
301 * someone has compromised a name server. More likely someone
302 * botched it, but that could be dangerous, too.
303 */
304
305 if (found == 0)
306 tcpd_warn("host name/address mismatch: %s != %.*s",
307 host->addr, STRING_LENGTH, service->h_host);
308 }
309 STRN_CPY(host->name, found ? service->h_host : paranoid,
310 sizeof(host->name));
311 netdir_free((void *) servlist, ND_HOSTSERVLIST);
312 }
313 }
314
315 /* tli_error - convert tli error number to text */
316
317 static char *tli_error()
318 {
319 static char buf[40];
320
321 if (t_errno != TSYSERR) {
322 if (t_errno < 0 || t_errno >= t_nerr) {
323 sprintf(buf, "Unknown TLI error %d", t_errno);
324 return (buf);
325 } else {
326 return (t_errlist[t_errno]);
327 }
328 } else {
329 if (errno < 0 || errno >= sys_nerr) {
330 sprintf(buf, "Unknown UNIX error %d", errno);
331 return (buf);
332 } else {
333 return (sys_errlist[errno]);
334 }
335 }
336 }
337
338 /* tli_sink - absorb unreceived datagram */
339
340 static void tli_sink(fd)
341 int fd;
342 {
343 struct t_unitdata *unit;
344 int flags;
345
346 /*
347 * Something went wrong. Absorb the datagram to keep inetd from looping.
348 * Allocate storage for address, control and data. If that fails, sleep
349 * for a couple of seconds in an attempt to keep inetd from looping too
350 * fast.
351 */
352
353 if ((unit = (struct t_unitdata *) t_alloc(fd, T_UNITDATA, T_ALL)) == 0) {
354 tcpd_warn("t_alloc: %s", tli_error());
355 sleep(5);
356 } else {
357 (void) t_rcvudata(fd, unit, &flags);
358 t_free((void *) unit, T_UNITDATA);
359 }
360 }
361
362 #endif /* TLI */