1 /* 2 * tli_host() determines the type of transport (connected, connectionless), 3 * the transport address of a client host, and the transport address of a 4 * server endpoint. In addition, it provides methods to map a transport 5 * address to a printable host name or address. Socket address results are 6 * in static memory; tli structures are allocated from the heap. 7 * 8 * The result from the hostname lookup method is STRING_PARANOID when a host 9 * pretends to have someone elses name, or when a host name is available but 10 * could not be verified. 11 * 12 * Diagnostics are reported through syslog(3). 13 * 14 * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands. 15 * 16 * $FreeBSD$ 17 */ 18 19 #ifndef lint 20 static char sccsid[] = "@(#) tli.c 1.15 97/03/21 19:27:25"; 21 #endif 22 23 #ifdef TLI 24 25 /* System libraries. */ 26 27 #include <sys/types.h> 28 #include <sys/param.h> 29 #include <sys/stream.h> 30 #include <sys/stat.h> 31 #include <sys/mkdev.h> 32 #include <sys/tiuser.h> 33 #include <sys/timod.h> 34 #include <sys/socket.h> 35 #include <netinet/in.h> 36 #include <stdio.h> 37 #include <syslog.h> 38 #include <errno.h> 39 #include <netconfig.h> 40 #include <netdir.h> 41 #include <string.h> 42 43 extern char *nc_sperror(); 44 extern char *sys_errlist[]; 45 extern int sys_nerr; 46 extern int t_errno; 47 extern char *t_errlist[]; 48 extern int t_nerr; 49 50 /* Local stuff. */ 51 52 #include "tcpd.h" 53 54 /* Forward declarations. */ 55 56 static void tli_endpoints(); 57 static struct netconfig *tli_transport(); 58 static void tli_hostname(); 59 static void tli_hostaddr(); 60 static void tli_cleanup(); 61 static char *tli_error(); 62 static void tli_sink(); 63 64 /* tli_host - look up endpoint addresses and install conversion methods */ 65 66 void tli_host(struct request_info *request) 67 { 68 #ifdef INET6 69 static struct sockaddr_storage client; 70 static struct sockaddr_storage server; 71 #else 72 static struct sockaddr_in client; 73 static struct sockaddr_in server; 74 #endif 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 #ifdef INET6 84 if ((request->config = tli_transport(request->fd)) != 0 85 && (STR_EQ(request->config->nc_protofmly, "inet") || 86 STR_EQ(request->config->nc_protofmly, "inet6"))) { 87 #else 88 if ((request->config = tli_transport(request->fd)) != 0 89 && STR_EQ(request->config->nc_protofmly, "inet")) { 90 #endif 91 if (request->client->unit != 0) { 92 #ifdef INET6 93 client = *(struct sockaddr_storage *) request->client->unit->addr.buf; 94 request->client->sin = (struct sockaddr *) &client; 95 #else 96 client = *(struct sockaddr_in *) request->client->unit->addr.buf; 97 request->client->sin = &client; 98 #endif 99 } 100 if (request->server->unit != 0) { 101 #ifdef INET6 102 server = *(struct sockaddr_storage *) request->server->unit->addr.buf; 103 request->server->sin = (struct sockaddr *) &server; 104 #else 105 server = *(struct sockaddr_in *) request->server->unit->addr.buf; 106 request->server->sin = &server; 107 #endif 108 } 109 tli_cleanup(request); 110 sock_methods(request); 111 } else { 112 request->hostname = tli_hostname; 113 request->hostaddr = tli_hostaddr; 114 request->cleanup = tli_cleanup; 115 } 116 } 117 118 /* tli_cleanup - cleanup some dynamically-allocated data structures */ 119 120 static void tli_cleanup(struct request_info *request) 121 { 122 if (request->config != 0) 123 freenetconfigent(request->config); 124 if (request->client->unit != 0) 125 t_free((char *) request->client->unit, T_UNITDATA); 126 if (request->server->unit != 0) 127 t_free((char *) request->server->unit, T_UNITDATA); 128 } 129 130 /* tli_endpoints - determine TLI client and server endpoint information */ 131 132 static void tli_endpoints(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(int fd) 186 { 187 struct stat from_client; 188 struct stat from_config; 189 void *handlep; 190 struct netconfig *config; 191 192 /* 193 * Assuming that the network device is a clone device, we must compare 194 * the major device number of stdin to the minor device number of the 195 * devices listed in the netconfig table. 196 */ 197 198 if (fstat(fd, &from_client) != 0) { 199 tcpd_warn("fstat(fd %d): %m", fd); 200 return (0); 201 } 202 if ((handlep = setnetconfig()) == 0) { 203 tcpd_warn("setnetconfig: %m"); 204 return (0); 205 } 206 while (config = getnetconfig(handlep)) { 207 if (stat(config->nc_device, &from_config) == 0) { 208 #ifdef NO_CLONE_DEVICE 209 /* 210 * If the network devices are not cloned (as is the case for 211 * Solaris 8 Beta), we must compare the major device numbers. 212 */ 213 if (major(from_config.st_rdev) == major(from_client.st_rdev)) 214 #else 215 if (minor(from_config.st_rdev) == major(from_client.st_rdev)) 216 #endif 217 break; 218 } 219 } 220 if (config == 0) { 221 tcpd_warn("unable to identify transport protocol"); 222 return (0); 223 } 224 225 /* 226 * Something else may clobber our getnetconfig() result, so we'd better 227 * acquire our private copy. 228 */ 229 230 if ((config = getnetconfigent(config->nc_netid)) == 0) { 231 tcpd_warn("getnetconfigent(%s): %s", config->nc_netid, nc_sperror()); 232 return (0); 233 } 234 return (config); 235 } 236 237 /* tli_hostaddr - map TLI transport address to printable address */ 238 239 static void tli_hostaddr(struct host_info *host) 240 { 241 struct request_info *request = host->request; 242 struct netconfig *config = request->config; 243 struct t_unitdata *unit = host->unit; 244 char *uaddr; 245 246 if (config != 0 && unit != 0 247 && (uaddr = taddr2uaddr(config, &unit->addr)) != 0) { 248 STRN_CPY(host->addr, uaddr, sizeof(host->addr)); 249 free(uaddr); 250 } 251 } 252 253 /* tli_hostname - map TLI transport address to hostname */ 254 255 static void tli_hostname(struct host_info *host) 256 { 257 struct request_info *request = host->request; 258 struct netconfig *config = request->config; 259 struct t_unitdata *unit = host->unit; 260 struct nd_hostservlist *servlist; 261 262 if (config != 0 && unit != 0 263 && netdir_getbyaddr(config, &servlist, &unit->addr) == ND_OK) { 264 265 struct nd_hostserv *service = servlist->h_hostservs; 266 struct nd_addrlist *addr_list; 267 int found = 0; 268 269 if (netdir_getbyname(config, service, &addr_list) != ND_OK) { 270 271 /* 272 * Unable to verify that the name matches the address. This may 273 * be a transient problem or a botched name server setup. We 274 * decide to play safe. 275 */ 276 277 tcpd_warn("can't verify hostname: netdir_getbyname(%.*s) failed", 278 STRING_LENGTH, service->h_host); 279 280 } else { 281 282 /* 283 * Look up the host address in the address list we just got. The 284 * comparison is done on the textual representation, because the 285 * transport address is an opaque structure that may have holes 286 * with uninitialized garbage. This approach obviously loses when 287 * the address does not have a textual representation. 288 */ 289 290 char *uaddr = eval_hostaddr(host); 291 char *ua; 292 int i; 293 294 for (i = 0; found == 0 && i < addr_list->n_cnt; i++) { 295 if ((ua = taddr2uaddr(config, &(addr_list->n_addrs[i]))) != 0) { 296 found = !strcmp(ua, uaddr); 297 free(ua); 298 } 299 } 300 netdir_free((void *) addr_list, ND_ADDRLIST); 301 302 /* 303 * When the host name does not map to the initial address, assume 304 * someone has compromised a name server. More likely someone 305 * botched it, but that could be dangerous, too. 306 */ 307 308 if (found == 0) 309 tcpd_warn("host name/address mismatch: %s != %.*s", 310 host->addr, STRING_LENGTH, service->h_host); 311 } 312 STRN_CPY(host->name, found ? service->h_host : paranoid, 313 sizeof(host->name)); 314 netdir_free((void *) servlist, ND_HOSTSERVLIST); 315 } 316 } 317 318 /* tli_error - convert tli error number to text */ 319 320 static char *tli_error() 321 { 322 static char buf[40]; 323 324 if (t_errno != TSYSERR) { 325 if (t_errno < 0 || t_errno >= t_nerr) { 326 sprintf(buf, "Unknown TLI error %d", t_errno); 327 return (buf); 328 } else { 329 return (t_errlist[t_errno]); 330 } 331 } else { 332 if (errno < 0 || errno >= sys_nerr) { 333 sprintf(buf, "Unknown UNIX error %d", errno); 334 return (buf); 335 } else { 336 return (sys_errlist[errno]); 337 } 338 } 339 } 340 341 /* tli_sink - absorb unreceived datagram */ 342 343 static void tli_sink(int fd) 344 { 345 struct t_unitdata *unit; 346 int flags; 347 348 /* 349 * Something went wrong. Absorb the datagram to keep inetd from looping. 350 * Allocate storage for address, control and data. If that fails, sleep 351 * for a couple of seconds in an attempt to keep inetd from looping too 352 * fast. 353 */ 354 355 if ((unit = (struct t_unitdata *) t_alloc(fd, T_UNITDATA, T_ALL)) == 0) { 356 tcpd_warn("t_alloc: %s", tli_error()); 357 sleep(5); 358 } else { 359 (void) t_rcvudata(fd, unit, &flags); 360 t_free((void *) unit, T_UNITDATA); 361 } 362 } 363 364 #endif /* TLI */ 365