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