1 /*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 char copyright[] = 10 "@(#) Copyright (c) 1990 The Regents of the University of California.\n\ 11 All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)mail.local.c 5.12 (Berkeley) 04/30/93"; 16 #endif /* not lint */ 17 18 #include <sys/param.h> 19 #include <sys/stat.h> 20 #include <sys/socket.h> 21 22 #include <netinet/in.h> 23 24 #include <errno.h> 25 #include <fcntl.h> 26 #include <netdb.h> 27 #include <pwd.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <sysexits.h> 32 #include <syslog.h> 33 #include <time.h> 34 #include <unistd.h> 35 36 #if __STDC__ 37 #include <stdarg.h> 38 #else 39 #include <varargs.h> 40 #endif 41 42 #include "pathnames.h" 43 44 int eval = EX_OK; /* sysexits.h error value. */ 45 46 void deliver __P((int, char *)); 47 void e_to_sys __P((int)); 48 __dead void err __P((const char *, ...)); 49 void notifybiff __P((char *)); 50 int store __P((char *)); 51 void usage __P((void)); 52 void vwarn __P((const char *, _BSD_VA_LIST_)); 53 void warn __P((const char *, ...)); 54 55 int 56 main(argc, argv) 57 int argc; 58 char *argv[]; 59 { 60 struct passwd *pw; 61 int ch, fd; 62 uid_t uid; 63 char *from; 64 65 openlog("mail.local", 0, LOG_MAIL); 66 67 from = NULL; 68 while ((ch = getopt(argc, argv, "df:r:")) != EOF) 69 switch(ch) { 70 case 'd': /* Backward compatible. */ 71 break; 72 case 'f': 73 case 'r': /* Backward compatible. */ 74 if (from != NULL) { 75 warn("multiple -f options"); 76 usage(); 77 } 78 from = optarg; 79 break; 80 case '?': 81 default: 82 usage(); 83 } 84 argc -= optind; 85 argv += optind; 86 87 if (!*argv) 88 usage(); 89 90 /* 91 * If from not specified, use the name from getlogin() if the 92 * uid matches, otherwise, use the name from the password file 93 * corresponding to the uid. 94 */ 95 uid = getuid(); 96 if (!from && (!(from = getlogin()) || 97 !(pw = getpwnam(from)) || pw->pw_uid != uid)) 98 from = (pw = getpwuid(uid)) ? pw->pw_name : "???"; 99 100 /* 101 * There is no way to distinguish the error status of one delivery 102 * from the rest of the deliveries. So, if we failed hard on one 103 * or more deliveries, but had no failures on any of the others, we 104 * return a hard failure. If we failed temporarily on one or more 105 * deliveries, we return a temporary failure regardless of the other 106 * failures. This results in the delivery being reattempted later 107 * at the expense of repeated failures and multiple deliveries. 108 */ 109 for (fd = store(from); *argv; ++argv) 110 deliver(fd, *argv); 111 exit(eval); 112 } 113 114 int 115 store(from) 116 char *from; 117 { 118 FILE *fp; 119 time_t tval; 120 int fd, eline; 121 char *tn, line[2048]; 122 123 tn = strdup(_PATH_LOCTMP); 124 if ((fd = mkstemp(tn)) == -1 || (fp = fdopen(fd, "w+")) == NULL) { 125 e_to_sys(errno); 126 err("unable to open temporary file"); 127 } 128 (void)unlink(tn); 129 free(tn); 130 131 (void)time(&tval); 132 (void)fprintf(fp, "From %s %s", from, ctime(&tval)); 133 134 line[0] = '\0'; 135 for (eline = 1; fgets(line, sizeof(line), stdin);) { 136 if (line[0] == '\n') 137 eline = 1; 138 else { 139 if (eline && line[0] == 'F' && !bcmp(line, "From ", 5)) 140 (void)putc('>', fp); 141 eline = 0; 142 } 143 (void)fprintf(fp, "%s", line); 144 if (ferror(fp)) { 145 e_to_sys(errno); 146 err("temporary file write error"); 147 } 148 } 149 150 /* If message not newline terminated, need an extra. */ 151 if (!strchr(line, '\n')) 152 (void)putc('\n', fp); 153 /* Output a newline; note, empty messages are allowed. */ 154 (void)putc('\n', fp); 155 156 if (fflush(fp) == EOF || ferror(fp)) { 157 e_to_sys(errno); 158 err("temporary file write error"); 159 } 160 return (fd); 161 } 162 163 void 164 deliver(fd, name) 165 int fd; 166 char *name; 167 { 168 struct stat sb; 169 struct passwd *pw; 170 int mbfd, nr, nw, off; 171 char biffmsg[100], buf[8*1024], path[MAXPATHLEN]; 172 off_t curoff; 173 174 /* 175 * Disallow delivery to unknown names -- special mailboxes can be 176 * handled in the sendmail aliases file. 177 */ 178 if (!(pw = getpwnam(name))) { 179 if (eval != EX_TEMPFAIL) 180 eval = EX_UNAVAILABLE; 181 warn("unknown name: %s", name); 182 return; 183 } 184 185 (void)snprintf(path, sizeof(path), "%s/%s", _PATH_MAILDIR, name); 186 187 /* 188 * If the mailbox is a linked or a symlink, fail. 189 * 190 * If we created the mailbox, set the owner/group. If that fails, 191 * just return. Another process may have already opened it, so we 192 * can't unlink it. Historically, binmail set the owner/group at 193 * each mail delivery. We no longer do this, assuming that if the 194 * ownership or permissions were changed there was a reason. 195 * 196 * XXX 197 * open(2) should support flock'ing the file. 198 */ 199 if (lstat(path, &sb)) { 200 if ((mbfd = open(path, 201 O_APPEND|O_CREAT|O_EXCL|O_WRONLY, S_IRUSR|S_IWUSR)) < 0) 202 mbfd = open(path, O_APPEND|O_WRONLY, 0); 203 else if (fchown(mbfd, pw->pw_uid, pw->pw_gid)) { 204 e_to_sys(errno); 205 warn("chown %u.%u: %s", pw->pw_uid, pw->pw_gid, name); 206 return; 207 } 208 } else if (sb.st_nlink != 1 || S_ISLNK(sb.st_mode)) { 209 e_to_sys(errno); 210 warn("%s: linked file", path); 211 return; 212 } else 213 mbfd = open(path, O_APPEND|O_WRONLY, 0); 214 215 if (mbfd == -1) { 216 e_to_sys(errno); 217 warn("%s: %s", path, strerror(errno)); 218 return; 219 } 220 221 /* Wait until we can get a lock on the file. */ 222 if (flock(mbfd, LOCK_EX)) { 223 e_to_sys(errno); 224 warn("%s: %s", path, strerror(errno)); 225 goto err1; 226 } 227 228 /* Get the starting offset of the new message for biff. */ 229 curoff = lseek(mbfd, (off_t)0, SEEK_END); 230 (void)snprintf(biffmsg, sizeof(biffmsg), "%s@%qd\n", name, curoff); 231 232 /* Copy the message into the file. */ 233 if (lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) { 234 e_to_sys(errno); 235 warn("temporary file: %s", strerror(errno)); 236 goto err1; 237 } 238 while ((nr = read(fd, buf, sizeof(buf))) > 0) 239 for (off = 0; off < nr; nr -= nw, off += nw) 240 if ((nw = write(mbfd, buf + off, nr)) < 0) { 241 e_to_sys(errno); 242 warn("%s: %s", path, strerror(errno)); 243 goto err2;; 244 } 245 if (nr < 0) { 246 e_to_sys(errno); 247 warn("temporary file: %s", strerror(errno)); 248 goto err2;; 249 } 250 251 /* Flush to disk, don't wait for update. */ 252 if (fsync(mbfd)) { 253 e_to_sys(errno); 254 warn("%s: %s", path, strerror(errno)); 255 err2: (void)ftruncate(mbfd, curoff); 256 err1: (void)close(mbfd); 257 return; 258 } 259 260 /* Close and check -- NFS doesn't write until the close. */ 261 if (close(mbfd)) { 262 e_to_sys(errno); 263 warn("%s: %s", path, strerror(errno)); 264 return; 265 } 266 267 notifybiff(biffmsg); 268 } 269 270 void 271 notifybiff(msg) 272 char *msg; 273 { 274 static struct sockaddr_in addr; 275 static int f = -1; 276 struct hostent *hp; 277 struct servent *sp; 278 int len; 279 280 if (!addr.sin_family) { 281 /* Be silent if biff service not available. */ 282 if (!(sp = getservbyname("biff", "udp"))) 283 return; 284 if (!(hp = gethostbyname("localhost"))) { 285 warn("localhost: %s", strerror(errno)); 286 return; 287 } 288 addr.sin_family = hp->h_addrtype; 289 bcopy(hp->h_addr, &addr.sin_addr, hp->h_length); 290 addr.sin_port = sp->s_port; 291 } 292 if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { 293 warn("socket: %s", strerror(errno)); 294 return; 295 } 296 len = strlen(msg) + 1; 297 if (sendto(f, msg, len, 0, (struct sockaddr *)&addr, sizeof(addr)) 298 != len) 299 warn("sendto biff: %s", strerror(errno)); 300 } 301 302 void 303 usage() 304 { 305 eval = EX_USAGE; 306 err("usage: mail.local [-f from] user ..."); 307 } 308 309 void 310 #if __STDC__ 311 err(const char *fmt, ...) 312 #else 313 err(fmt, va_alist) 314 const char *fmt; 315 va_dcl 316 #endif 317 { 318 va_list ap; 319 320 #if __STDC__ 321 va_start(ap, fmt); 322 #else 323 va_start(ap); 324 #endif 325 vwarn(fmt, ap); 326 va_end(ap); 327 328 exit(eval); 329 } 330 331 void 332 #if __STDC__ 333 warn(const char *fmt, ...) 334 #else 335 warn(fmt, va_alist) 336 const char *fmt; 337 va_dcl 338 #endif 339 { 340 va_list ap; 341 342 #if __STDC__ 343 va_start(ap, fmt); 344 #else 345 va_start(ap); 346 #endif 347 vwarn(fmt, ap); 348 va_end(ap); 349 } 350 351 void 352 vwarn(fmt, ap) 353 const char *fmt; 354 _BSD_VA_LIST_ ap; 355 { 356 /* 357 * Log the message to stderr. 358 * 359 * Don't use LOG_PERROR as an openlog() flag to do this, 360 * it's not portable enough. 361 */ 362 if (eval != EX_USAGE) 363 (void)fprintf(stderr, "mail.local: "); 364 (void)vfprintf(stderr, fmt, ap); 365 (void)fprintf(stderr, "\n"); 366 367 /* Log the message to syslog. */ 368 vsyslog(LOG_ERR, fmt, ap); 369 } 370 371 /* 372 * e_to_sys -- 373 * Guess which errno's are temporary. Gag me. 374 */ 375 void 376 e_to_sys(num) 377 int num; 378 { 379 /* Temporary failures override hard errors. */ 380 if (eval == EX_TEMPFAIL) 381 return; 382 383 switch(num) { /* Hopefully temporary errors. */ 384 #ifdef EAGAIN 385 case EAGAIN: /* Resource temporarily unavailable */ 386 #endif 387 #ifdef EDQUOT 388 case EDQUOT: /* Disc quota exceeded */ 389 #endif 390 #ifdef EBUSY 391 case EBUSY: /* Device busy */ 392 #endif 393 #ifdef EPROCLIM 394 case EPROCLIM: /* Too many processes */ 395 #endif 396 #ifdef EUSERS 397 case EUSERS: /* Too many users */ 398 #endif 399 #ifdef ECONNABORTED 400 case ECONNABORTED: /* Software caused connection abort */ 401 #endif 402 #ifdef ECONNREFUSED 403 case ECONNREFUSED: /* Connection refused */ 404 #endif 405 #ifdef ECONNRESET 406 case ECONNRESET: /* Connection reset by peer */ 407 #endif 408 #ifdef EDEADLK 409 case EDEADLK: /* Resource deadlock avoided */ 410 #endif 411 #ifdef EFBIG 412 case EFBIG: /* File too large */ 413 #endif 414 #ifdef EHOSTDOWN 415 case EHOSTDOWN: /* Host is down */ 416 #endif 417 #ifdef EHOSTUNREACH 418 case EHOSTUNREACH: /* No route to host */ 419 #endif 420 #ifdef EMFILE 421 case EMFILE: /* Too many open files */ 422 #endif 423 #ifdef ENETDOWN 424 case ENETDOWN: /* Network is down */ 425 #endif 426 #ifdef ENETRESET 427 case ENETRESET: /* Network dropped connection on reset */ 428 #endif 429 #ifdef ENETUNREACH 430 case ENETUNREACH: /* Network is unreachable */ 431 #endif 432 #ifdef ENFILE 433 case ENFILE: /* Too many open files in system */ 434 #endif 435 #ifdef ENOBUFS 436 case ENOBUFS: /* No buffer space available */ 437 #endif 438 #ifdef ENOMEM 439 case ENOMEM: /* Cannot allocate memory */ 440 #endif 441 #ifdef ENOSPC 442 case ENOSPC: /* No space left on device */ 443 #endif 444 #ifdef EROFS 445 case EROFS: /* Read-only file system */ 446 #endif 447 #ifdef ESTALE 448 case ESTALE: /* Stale NFS file handle */ 449 #endif 450 #ifdef ETIMEDOUT 451 case ETIMEDOUT: /* Connection timed out */ 452 #endif 453 #if defined(EWOULDBLOCK) && (EWOULDBLOCK != EAGAIN) 454 case EWOULDBLOCK: /* Operation would block. */ 455 #endif 456 eval = EX_TEMPFAIL; 457 break; 458 default: 459 eval = EX_UNAVAILABLE; 460 break; 461 } 462 } 463