1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)rmjob.c 8.2 (Berkeley) 4/28/95 34 * $FreeBSD: src/usr.sbin/lpr/common_source/rmjob.c,v 1.12.2.5 2001/06/25 01:00:56 gad Exp $ 35 */ 36 37 #include <sys/param.h> 38 #include <sys/uio.h> 39 40 #include <ctype.h> 41 #include <dirent.h> 42 #include <errno.h> 43 #include <signal.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #define psignal foil_gcc_psignal 48 #define sys_siglist foil_gcc_siglist 49 #include <unistd.h> 50 #undef psignal 51 #undef sys_siglist 52 53 #include "lp.h" 54 #include "lp.local.h" 55 #include "pathnames.h" 56 57 /* 58 * rmjob - remove the specified jobs from the queue. 59 */ 60 61 /* 62 * Stuff for handling lprm specifications 63 */ 64 static char root[] = "root"; 65 static int all = 0; /* eliminate all files (root only) */ 66 static int cur_daemon; /* daemon's pid */ 67 static char current[7+MAXHOSTNAMELEN]; /* active control file name */ 68 69 extern uid_t uid, euid; /* real and effective user id's */ 70 71 static void alarmhandler(int _signo); 72 static void do_unlink(char *_file); 73 74 void 75 rmjob(const char *printer) 76 { 77 int i, nitems; 78 int assasinated = 0; 79 struct dirent **files; 80 char *cp; 81 struct printer myprinter, *pp = &myprinter; 82 83 init_printer(pp); 84 if ((i = getprintcap(printer, pp)) < 0) 85 fatal(pp, "getprintcap: %s", pcaperr(i)); 86 if ((cp = checkremote(pp))) { 87 printf("Warning: %s\n", cp); 88 free(cp); 89 } 90 91 /* 92 * If the format was `lprm -' and the user isn't the super-user, 93 * then fake things to look like he said `lprm user'. 94 */ 95 if (users < 0) { 96 if (getuid() == 0) 97 all = 1; /* all files in local queue */ 98 else { 99 user[0] = person; 100 users = 1; 101 } 102 } 103 if (!strcmp(person, "-all")) { 104 if (from_host == local_host) 105 fatal(pp, "The login name \"-all\" is reserved"); 106 all = 1; /* all those from 'from_host' */ 107 person = root; 108 } 109 110 seteuid(euid); 111 if (chdir(pp->spool_dir) < 0) 112 fatal(pp, "cannot chdir to spool directory"); 113 if ((nitems = scandir(".", &files, iscf, NULL)) < 0) 114 fatal(pp, "cannot access spool directory"); 115 seteuid(uid); 116 117 if (nitems) { 118 /* 119 * Check for an active printer daemon (in which case we 120 * kill it if it is reading our file) then remove stuff 121 * (after which we have to restart the daemon). 122 */ 123 if (lockchk(pp, pp->lock_file) && chk(current)) { 124 seteuid(euid); 125 assasinated = kill(cur_daemon, SIGINT) == 0; 126 seteuid(uid); 127 if (!assasinated) 128 fatal(pp, "cannot kill printer daemon"); 129 } 130 /* 131 * process the files 132 */ 133 for (i = 0; i < nitems; i++) 134 process(pp, files[i]->d_name); 135 } 136 rmremote(pp); 137 /* 138 * Restart the printer daemon if it was killed 139 */ 140 if (assasinated && !startdaemon(pp)) 141 fatal(pp, "cannot restart printer daemon\n"); 142 exit(0); 143 } 144 145 /* 146 * Process a lock file: collect the pid of the active 147 * daemon and the file name of the active spool entry. 148 * Return boolean indicating existence of a lock file. 149 */ 150 int 151 lockchk(struct printer *pp, char *slockf) 152 { 153 FILE *fp; 154 int i, n; 155 156 seteuid(euid); 157 if ((fp = fopen(slockf, "r")) == NULL) { 158 if (errno == EACCES) 159 fatal(pp, "%s: %s", slockf, strerror(errno)); 160 else 161 return(0); 162 } 163 seteuid(uid); 164 if (!getline(fp)) { 165 fclose(fp); 166 return(0); /* no daemon present */ 167 } 168 cur_daemon = atoi(line); 169 if (kill(cur_daemon, 0) < 0 && errno != EPERM) { 170 fclose(fp); 171 return(0); /* no daemon present */ 172 } 173 for (i = 1; (n = fread(current, sizeof(char), sizeof(current), fp)) <= 0; i++) { 174 if (i > 5) { 175 n = 1; 176 break; 177 } 178 sleep(i); 179 } 180 current[n-1] = '\0'; 181 fclose(fp); 182 return(1); 183 } 184 185 /* 186 * Process a control file. 187 */ 188 void 189 process(const struct printer *pp, char *file) 190 { 191 FILE *cfp; 192 193 if (!chk(file)) 194 return; 195 seteuid(euid); 196 if ((cfp = fopen(file, "r")) == NULL) 197 fatal(pp, "cannot open %s", file); 198 seteuid(uid); 199 while (getline(cfp)) { 200 switch (line[0]) { 201 case 'U': /* unlink associated files */ 202 if (strchr(line+1, '/') || strncmp(line+1, "df", 2)) 203 break; 204 do_unlink(line+1); 205 } 206 } 207 fclose(cfp); 208 do_unlink(file); 209 } 210 211 static void 212 do_unlink(char *file) 213 { 214 int ret; 215 216 if (from_host != local_host) 217 printf("%s: ", local_host); 218 seteuid(euid); 219 ret = unlink(file); 220 seteuid(uid); 221 printf(ret ? "cannot dequeue %s\n" : "%s dequeued\n", file); 222 } 223 224 /* 225 * Do the dirty work in checking 226 */ 227 int 228 chk(char *file) 229 { 230 int *r, n; 231 char **u, *cp; 232 FILE *cfp; 233 234 /* 235 * Check for valid cf file name (mostly checking current). 236 */ 237 if (strlen(file) < 7 || file[0] != 'c' || file[1] != 'f') 238 return(0); 239 240 if (all && (from_host == local_host || !strcmp(from_host, file+6))) 241 return(1); 242 243 /* 244 * get the owner's name from the control file. 245 */ 246 seteuid(euid); 247 if ((cfp = fopen(file, "r")) == NULL) 248 return(0); 249 seteuid(uid); 250 while (getline(cfp)) { 251 if (line[0] == 'P') 252 break; 253 } 254 fclose(cfp); 255 if (line[0] != 'P') 256 return(0); 257 258 if (users == 0 && requests == 0) 259 return(!strcmp(file, current) && isowner(line+1, file)); 260 /* 261 * Check the request list 262 */ 263 for (n = 0, cp = file+3; isdigit(*cp); ) 264 n = n * 10 + (*cp++ - '0'); 265 for (r = requ; r < &requ[requests]; r++) 266 if (*r == n && isowner(line+1, file)) 267 return(1); 268 /* 269 * Check to see if it's in the user list 270 */ 271 for (u = user; u < &user[users]; u++) 272 if (!strcmp(*u, line+1) && isowner(line+1, file)) 273 return(1); 274 return(0); 275 } 276 277 /* 278 * If root is removing a file on the local machine, allow it. 279 * If root is removing a file from a remote machine, only allow 280 * files sent from the remote machine to be removed. 281 * Normal users can only remove the file from where it was sent. 282 */ 283 int 284 isowner(char *owner, char *file) 285 { 286 if (!strcmp(person, root) && (from_host == local_host || 287 !strcmp(from_host, file+6))) 288 return (1); 289 if (!strcmp(person, owner) && !strcmp(from_host, file+6)) 290 return (1); 291 if (from_host != local_host) 292 printf("%s: ", local_host); 293 printf("%s: Permission denied\n", file); 294 return(0); 295 } 296 297 /* 298 * Check to see if we are sending files to a remote machine. If we are, 299 * then try removing files on the remote machine. 300 */ 301 void 302 rmremote(const struct printer *pp) 303 { 304 int i, elem, firstreq, niov, rem, totlen; 305 char buf[BUFSIZ]; 306 void (*savealrm)(int); 307 struct iovec *iov; 308 309 if (!pp->remote) 310 return; /* not sending to a remote machine */ 311 312 /* 313 * Flush stdout so the user can see what has been deleted 314 * while we wait (possibly) for the connection. 315 */ 316 fflush(stdout); 317 318 /* 319 * Counting: 320 * 4 == "\5" + remote_queue + " " + person 321 * 2 * users == " " + user[i] for each user 322 * requests == asprintf results for each request 323 * 1 == "\n" 324 * Although laborious, doing it this way makes it possible for 325 * us to process requests of indeterminate length without 326 * applying an arbitrary limit. Arbitrary Limits Are Bad (tm). 327 */ 328 if (users > 0) 329 niov = 4 + 2 * users + requests + 1; 330 else 331 niov = 4 + requests + 1; 332 iov = malloc(niov * sizeof *iov); 333 if (iov == NULL) 334 fatal(pp, "out of memory in rmremote()"); 335 iov[0].iov_base = "\5"; 336 iov[1].iov_base = pp->remote_queue; 337 iov[2].iov_base = " "; 338 iov[3].iov_base = all ? "-all" : person; 339 elem = 4; 340 for (i = 0; i < users; i++) { 341 iov[elem].iov_base = " "; 342 iov[elem + 1].iov_base = user[i]; 343 elem += 2; 344 } 345 firstreq = elem; 346 for (i = 0; i < requests; i++) { 347 asprintf((char **)&iov[elem].iov_base, " %d", requ[i]); 348 if (iov[elem].iov_base == 0) 349 fatal(pp, "out of memory in rmremote()"); 350 elem++; 351 } 352 iov[elem++].iov_base = "\n"; 353 for (totlen = i = 0; i < niov; i++) 354 totlen += (iov[i].iov_len = strlen(iov[i].iov_base)); 355 356 savealrm = signal(SIGALRM, alarmhandler); 357 alarm(pp->conn_timeout); 358 rem = getport(pp, pp->remote_host, 0); 359 signal(SIGALRM, savealrm); 360 if (rem < 0) { 361 if (from_host != local_host) 362 printf("%s: ", local_host); 363 printf("connection to %s is down\n", pp->remote_host); 364 } else { 365 if (writev(rem, iov, niov) != totlen) 366 fatal(pp, "Lost connection"); 367 while ((i = read(rem, buf, sizeof(buf))) > 0) 368 fwrite(buf, 1, i, stdout); 369 close(rem); 370 } 371 for (i = 0; i < requests; i++) 372 free(iov[firstreq + i].iov_base); 373 free(iov); 374 } 375 376 /* 377 * Return 1 if the filename begins with 'cf' 378 */ 379 int 380 iscf(const struct dirent *d) 381 { 382 return(d->d_name[0] == 'c' && d->d_name[1] == 'f'); 383 } 384 385 void 386 alarmhandler(int signo __unused) 387 { 388 /* the signal is ignored */ 389 /* (the '__unused' is just to avoid a compile-time warning) */ 390 } 391