1 /* 2 * Copyright (c) 1983 Eric P. Allman 3 * Copyright (c) 1988 Regents of the University of California. 4 * All rights reserved. 5 * 6 * %sccs.include.redist.c% 7 */ 8 9 #ifndef lint 10 #ifdef USERDB 11 static char sccsid [] = "@(#)udb.c 5.12 (Berkeley) 12/12/91 (with USERDB)"; 12 #else 13 static char sccsid [] = "@(#)udb.c 5.12 (Berkeley) 12/12/91 (without USERDB)"; 14 #endif 15 #endif 16 17 #include "sendmail.h" 18 19 #ifdef USERDB 20 21 #include <sys/file.h> 22 #include <sys/time.h> 23 #include <fcntl.h> 24 #include <netdb.h> 25 #include <db.h> 26 27 /* 28 ** UDBEXPAND.C -- interface between sendmail and Berkeley User Data Base. 29 ** 30 ** This depends on the 4.4BSD db package. 31 */ 32 33 34 struct udbent 35 { 36 char *udb_spec; /* string version of spec */ 37 int udb_type; /* type of entry */ 38 union 39 { 40 /* type UE_REMOTE -- do remote call for lookup */ 41 struct 42 { 43 struct sockaddr_in _udb_addr; /* address */ 44 int _udb_timeout; /* timeout */ 45 } udb_remote; 46 #define udb_addr udb_u.udb_remote._udb_addr 47 #define udb_timeout udb_u.udb_remote._udb_timeout 48 49 /* type UE_FORWARD -- forward message to remote */ 50 struct 51 { 52 char *_udb_fwdhost; /* name of forward host */ 53 } udb_forward; 54 #define udb_fwdhost udb_u.udb_forward._udb_fwdhost 55 56 /* type UE_LOOKUP -- lookup in local database */ 57 struct 58 { 59 char *_udb_dbname; /* pathname of database */ 60 DB *_udb_dbp; /* open database ptr */ 61 } udb_lookup; 62 #define udb_dbname udb_u.udb_lookup._udb_dbname 63 #define udb_dbp udb_u.udb_lookup._udb_dbp 64 } udb_u; 65 }; 66 67 #define UDB_EOLIST 0 /* end of list */ 68 #define UDB_SKIP 1 /* skip this entry */ 69 #define UDB_REMOTE 2 /* look up in remote database */ 70 #define UDB_LOOKUP 3 /* look up in local database */ 71 #define UDB_FORWARD 4 /* forward to remote host */ 72 73 #define MAXUDBENT 10 /* maximum number of UDB entries */ 74 75 76 struct option 77 { 78 char *name; 79 char *val; 80 }; 81 /* 82 ** UDBEXPAND -- look up user in database and expand 83 ** 84 ** Parameters: 85 ** a -- address to expand. 86 ** sendq -- pointer to head of sendq to put the expansions in. 87 ** 88 ** Returns: 89 ** none. 90 ** 91 ** Side Effects: 92 ** Modifies sendq. 93 */ 94 95 int UdbPort = 1616; 96 int UdbTimeout = 10; 97 98 struct udbent UdbEnts[MAXUDBENT + 1]; 99 int UdbSock = -1; 100 101 void 102 udbexpand(a, sendq) 103 register ADDRESS *a; 104 ADDRESS **sendq; 105 { 106 int i; 107 register char *p; 108 DBT key; 109 DBT info; 110 static bool firstcall = TRUE; 111 bool breakout; 112 register struct udbent *up; 113 int keylen; 114 char keybuf[128]; 115 char buf[8192]; 116 117 if (tTd(28, 1)) 118 printf("expand(%s)\n", a->q_paddr); 119 120 /* make certain we are supposed to send to this address */ 121 if (bitset(QDONTSEND, a->q_flags) || 122 UdbSpec == NULL || UdbSpec[0] == '\0') 123 return; 124 CurEnv->e_to = a->q_paddr; 125 126 /* on first call, locate the database */ 127 if (firstcall) 128 { 129 extern void _udbx_init(); 130 131 _udbx_init(); 132 firstcall = FALSE; 133 } 134 135 /* if name is too long, assume it won't match */ 136 if (strlen(a->q_user) > sizeof keybuf - 12) 137 return; 138 139 /* if name begins with a colon, it indicates our metadata */ 140 if (a->q_user[0] == ':') 141 return; 142 143 /* build actual database key */ 144 (void) strcpy(keybuf, a->q_user); 145 (void) strcat(keybuf, ":maildrop"); 146 keylen = strlen(keybuf); 147 148 breakout = FALSE; 149 for (up = UdbEnts; !breakout; up++) 150 { 151 char *user; 152 struct timeval timeout; 153 fd_set fdset; 154 155 /* 156 ** Select action based on entry type. 157 ** 158 ** On dropping out of this switch, "class" should 159 ** explain the type of the data, and "user" should 160 ** contain the user information. 161 */ 162 163 switch (up->udb_type) 164 { 165 case UDB_LOOKUP: 166 key.data = keybuf; 167 key.size = keylen; 168 i = (*up->udb_dbp->seq)(up->udb_dbp, &key, &info, R_CURSOR); 169 if (i != 0 || info.size <= 0) 170 { 171 if (i < 0) 172 syserr("udbexpand: db-get stat %s"); 173 if (tTd(28, 2)) 174 printf("expand: no match on %s\n", keybuf); 175 continue; 176 } 177 178 while (i == 0 && key.size == keylen && 179 bcmp(key.data, keybuf, keylen) == 0) 180 { 181 breakout = TRUE; 182 if (info.size < sizeof buf) 183 user = buf; 184 else 185 user = xalloc(info.size + 1); 186 bcopy(info.data, user, info.size); 187 user[info.size] = '\0'; 188 189 message(Arpa_Info, "expanded to %s", user); 190 AliasLevel++; 191 sendtolist(user, a, sendq); 192 AliasLevel--; 193 194 if (user != buf) 195 free(user); 196 197 /* get the next record */ 198 i = (*up->udb_dbp->seq)(up->udb_dbp, &key, &info, R_NEXT); 199 } 200 break; 201 202 case UDB_REMOTE: 203 /* not yet implemented */ 204 continue; 205 206 case UDB_FORWARD: 207 i = strlen(up->udb_fwdhost) + strlen(a->q_user) + 1; 208 if (i < sizeof buf) 209 user = buf; 210 else 211 user = xalloc(i + 1); 212 (void) sprintf(user, "%s@%s", a->q_user, up->udb_fwdhost); 213 message(Arpa_Info, "expanded to %s", user); 214 AliasLevel++; 215 sendtolist(user, a, sendq); 216 AliasLevel--; 217 if (user != buf) 218 free(user); 219 breakout = TRUE; 220 break; 221 222 case UDB_EOLIST: 223 breakout = TRUE; 224 continue; 225 226 default: 227 /* unknown entry type */ 228 continue; 229 } 230 } 231 } 232 233 #define MAXUDBOPTS 27 234 235 void 236 _udbx_init() 237 { 238 register char *p; 239 int i; 240 register struct udbent *up; 241 char buf[8192]; 242 243 # ifdef UDB_DEFAULT_SPEC 244 if (UdbSpec == NULL) 245 UdbSpec = UDB_DEFAULT_SPEC; 246 # endif 247 248 p = UdbSpec; 249 up = UdbEnts; 250 while (p != NULL) 251 { 252 char *spec; 253 auto int rcode; 254 int nopts; 255 int nmx; 256 register struct hostent *h; 257 char *mxhosts[MAXMXHOSTS + 1]; 258 struct option opts[MAXUDBOPTS + 1]; 259 260 while (*p == ' ' || *p == '\t' || *p == ',') 261 p++; 262 if (*p == '\0') 263 break; 264 spec = p; 265 p = index(p, ','); 266 if (p != NULL) 267 *p++ = '\0'; 268 269 /* extract options */ 270 nopts = _udb_parsespec(spec, opts, MAXUDBOPTS); 271 272 /* 273 ** Decode database specification. 274 ** 275 ** In the sendmail tradition, the leading character 276 ** defines the semantics of the rest of the entry. 277 ** 278 ** +hostname -- send a datagram to the udb server 279 ** on host "hostname" asking for the 280 ** home mail server for this user. 281 ** *hostname -- similar to +hostname, except that the 282 ** hostname is searched as an MX record; 283 ** resulting hosts are searched as for 284 ** +mxhostname. If no MX host is found, 285 ** this is the same as +hostname. 286 ** @hostname -- forward email to the indicated host. 287 ** This should be the last in the list, 288 ** since it always matches the input. 289 ** /dbname -- search the named database on the local 290 ** host using the Berkeley db package. 291 */ 292 293 switch (*spec) 294 { 295 case '+': /* search remote database */ 296 case '*': /* search remote database (expand MX) */ 297 if (*spec == '*') 298 { 299 nmx = getmxrr(spec + 1, mxhosts, "", &rcode); 300 if (tTd(28, 16)) 301 { 302 int i; 303 304 printf("getmxrr(%s): %d", spec + 1, nmx); 305 for (i = 0; i <= nmx; i++) 306 printf(" %s", mxhosts[i]); 307 printf("\n"); 308 } 309 } 310 else 311 { 312 nmx = 1; 313 mxhosts[0] = spec + 1; 314 } 315 316 for (i = 0; i < nmx; i++) 317 { 318 h = gethostbyname(mxhosts[i]); 319 if (h == NULL) 320 continue; 321 up->udb_type = UDB_REMOTE; 322 up->udb_addr.sin_family = h->h_addrtype; 323 bcopy(h->h_addr_list[0], 324 (char *) &up->udb_addr.sin_addr, 325 h->h_length); 326 up->udb_addr.sin_port = UdbPort; 327 up->udb_timeout = UdbTimeout; 328 up++; 329 } 330 331 /* set up a datagram socket */ 332 if (UdbSock < 0) 333 { 334 UdbSock = socket(AF_INET, SOCK_DGRAM, 0); 335 (void) fcntl(UdbSock, F_SETFD, 1); 336 } 337 break; 338 339 case '@': /* forward to remote host */ 340 up->udb_type = UDB_FORWARD; 341 up->udb_fwdhost = spec + 1; 342 up++; 343 break; 344 345 case '/': /* look up remote name */ 346 up->udb_dbname = spec; 347 up->udb_dbp = dbopen(spec, O_RDONLY, 0644, DB_BTREE, NULL); 348 if (up->udb_dbp == NULL) 349 break; 350 up->udb_type = UDB_LOOKUP; 351 up++; 352 break; 353 } 354 } 355 up->udb_type = UDB_EOLIST; 356 357 if (tTd(28, 4)) 358 { 359 for (up = UdbEnts; ; up++) 360 { 361 switch (up->udb_type) 362 { 363 case UDB_EOLIST: 364 return; 365 366 case UDB_REMOTE: 367 printf("REMOTE: addr %s, timeo %d\n", 368 inet_ntoa(up->udb_addr.sin_addr), 369 up->udb_timeout); 370 break; 371 372 case UDB_LOOKUP: 373 printf("LOOKUP: file %s\n", 374 up->udb_dbname); 375 break; 376 377 case UDB_FORWARD: 378 printf("FORWARD: host %s\n", 379 up->udb_fwdhost); 380 break; 381 382 default: 383 printf("UNKNOWN\n"); 384 break; 385 } 386 } 387 } 388 } 389 390 int 391 _udb_parsespec(udbspec, opt, maxopts) 392 char *udbspec; 393 struct option opt[]; 394 int maxopts; 395 { 396 register char *spec; 397 register char *spec_end; 398 register int optnum; 399 400 spec_end = index(udbspec, ':'); 401 for (optnum = 0; optnum < maxopts && (spec = spec_end) != NULL; optnum++) 402 { 403 register char *p; 404 405 while (isspace(*spec)) 406 spec++; 407 spec_end = index(spec, ':'); 408 if (spec_end != NULL) 409 *spec_end++ = '\0'; 410 411 opt[optnum].name = spec; 412 opt[optnum].val = NULL; 413 p = index(spec, '='); 414 if (p != NULL) 415 opt[optnum].val = ++p; 416 } 417 return optnum; 418 } 419 420 #else /* not USERDB */ 421 422 void 423 udbexpand(a, sendq) 424 ADDRESS *a; 425 ADDRESS **sendq; 426 { 427 return; 428 } 429 430 #endif /* USERDB */ 431