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