1 /* lfs_vnops.c 4.29 82/07/22 */ 2 3 #include "../h/param.h" 4 #include "../h/systm.h" 5 #include "../h/dir.h" 6 #include "../h/user.h" 7 #include "../h/file.h" 8 #include "../h/stat.h" 9 #include "../h/inode.h" 10 #include "../h/fs.h" 11 #include "../h/buf.h" 12 #include "../h/proc.h" 13 #include "../h/inline.h" 14 #ifdef EFS 15 #include "../net/in.h" 16 #include "../h/efs.h" 17 #endif 18 #include "../h/quota.h" 19 20 chdir() 21 { 22 23 chdirec(&u.u_cdir); 24 } 25 26 chroot() 27 { 28 29 if (suser()) 30 chdirec(&u.u_rdir); 31 } 32 33 chdirec(ipp) 34 register struct inode **ipp; 35 { 36 register struct inode *ip; 37 struct a { 38 char *fname; 39 }; 40 41 ip = namei(uchar, 0, 1); 42 if(ip == NULL) 43 return; 44 if((ip->i_mode&IFMT) != IFDIR) { 45 u.u_error = ENOTDIR; 46 goto bad; 47 } 48 if(access(ip, IEXEC)) 49 goto bad; 50 iunlock(ip); 51 if (*ipp) 52 irele(*ipp); 53 *ipp = ip; 54 return; 55 56 bad: 57 iput(ip); 58 } 59 60 /* 61 * Open system call. 62 */ 63 open() 64 { 65 register struct inode *ip; 66 register struct a { 67 char *fname; 68 int rwmode; 69 } *uap; 70 71 uap = (struct a *)u.u_ap; 72 ip = namei(uchar, 0, 1); 73 if (ip == NULL) 74 return; 75 open1(ip, ++uap->rwmode, 0); 76 } 77 78 /* 79 * Creat system call. 80 */ 81 creat() 82 { 83 register struct inode *ip; 84 register struct a { 85 char *fname; 86 int fmode; 87 } *uap; 88 89 uap = (struct a *)u.u_ap; 90 ip = namei(uchar, 1, 1); 91 if (ip == NULL) { 92 if (u.u_error) 93 return; 94 ip = maknode(uap->fmode&07777&(~ISVTX)); 95 if (ip==NULL) 96 return; 97 open1(ip, FWRITE, 2); 98 } else 99 open1(ip, FWRITE, 1); 100 } 101 102 /* 103 * Common code for open and creat. 104 * Check permissions, allocate an open file structure, 105 * and call the device open routine if any. 106 */ 107 open1(ip, mode, trf) 108 register struct inode *ip; 109 register mode; 110 { 111 register struct file *fp; 112 int i; 113 114 if (trf != 2) { 115 if (mode&FREAD) 116 (void) access(ip, IREAD); 117 if (mode&FWRITE) { 118 (void) access(ip, IWRITE); 119 if ((ip->i_mode&IFMT) == IFDIR) 120 u.u_error = EISDIR; 121 } 122 } 123 if (u.u_error) { 124 iput(ip); 125 return; 126 } 127 if (trf == 1) 128 itrunc(ip); 129 iunlock(ip); 130 if ((fp = falloc()) == NULL) 131 goto out; 132 fp->f_flag = mode&(FREAD|FWRITE); 133 i = u.u_r.r_val1; 134 fp->f_inode = ip; 135 #ifdef EFS 136 openi(ip, mode&(FREAD|FWRITE), trf); 137 #else 138 openi(ip, mode&(FREAD|FWRITE)); 139 #endif 140 if (u.u_error == 0) 141 return; 142 u.u_ofile[i] = NULL; 143 fp->f_count--; 144 out: 145 irele(ip); 146 } 147 148 /* 149 * Mknod system call 150 */ 151 mknod() 152 { 153 register struct inode *ip; 154 register struct a { 155 char *fname; 156 int fmode; 157 int dev; 158 } *uap; 159 160 uap = (struct a *)u.u_ap; 161 if (suser()) { 162 ip = namei(uchar, 1, 0); 163 if (ip != NULL) { 164 u.u_error = EEXIST; 165 goto out; 166 } 167 } 168 if (u.u_error) 169 return; 170 ip = maknode(uap->fmode); 171 if (ip == NULL) 172 return; 173 if (uap->dev) { 174 /* 175 * Want to be able to use this to make badblock 176 * inodes, so don't truncate the dev number. 177 */ 178 ip->i_rdev = uap->dev; 179 ip->i_flag |= IACC|IUPD|ICHG; 180 } 181 182 out: 183 iput(ip); 184 } 185 186 /* 187 * link system call 188 */ 189 link() 190 { 191 register struct inode *ip, *xp; 192 register struct a { 193 char *target; 194 char *linkname; 195 } *uap; 196 197 uap = (struct a *)u.u_ap; 198 ip = namei(uchar, 0, 1); /* well, this routine is doomed anyhow */ 199 if (ip == NULL) 200 return; 201 if ((ip->i_mode&IFMT)==IFDIR && !suser()) { 202 iput(ip); 203 return; 204 } 205 ip->i_nlink++; 206 ip->i_flag |= ICHG; 207 iupdat(ip, &time, &time, 1); 208 iunlock(ip); 209 u.u_dirp = (caddr_t)uap->linkname; 210 xp = namei(uchar, 1, 0); 211 if (xp != NULL) { 212 u.u_error = EEXIST; 213 iput(xp); 214 goto out; 215 } 216 if (u.u_error) 217 goto out; 218 if (u.u_pdir->i_dev != ip->i_dev) { 219 iput(u.u_pdir); 220 u.u_error = EXDEV; 221 goto out; 222 } 223 wdir(ip); 224 out: 225 if (u.u_error) { 226 ip->i_nlink--; 227 ip->i_flag |= ICHG; 228 } 229 out1: 230 irele(ip); 231 } 232 233 /* 234 * symlink -- make a symbolic link 235 */ 236 symlink() 237 { 238 register struct a { 239 char *target; 240 char *linkname; 241 } *uap; 242 register struct inode *ip; 243 register char *tp; 244 register c, nc; 245 246 uap = (struct a *)u.u_ap; 247 tp = uap->target; 248 nc = 0; 249 while (c = fubyte(tp)) { 250 if (c < 0) { 251 u.u_error = EFAULT; 252 return; 253 } 254 tp++; 255 nc++; 256 } 257 u.u_dirp = uap->linkname; 258 ip = namei(uchar, 1, 0); 259 if (ip) { 260 iput(ip); 261 u.u_error = EEXIST; 262 return; 263 } 264 if (u.u_error) 265 return; 266 ip = maknode(IFLNK | 0777); 267 if (ip == NULL) 268 return; 269 u.u_base = uap->target; 270 u.u_count = nc; 271 u.u_offset = 0; 272 u.u_segflg = 0; 273 writei(ip); 274 iput(ip); 275 } 276 277 /* 278 * Unlink system call. 279 * Hard to avoid races here, especially 280 * in unlinking directories. 281 */ 282 unlink() 283 { 284 register struct inode *ip, *pp; 285 struct a { 286 char *fname; 287 }; 288 struct fs *fs; 289 struct buf *bp; 290 int lbn, bn, base; 291 int unlinkingdot = 0; 292 293 pp = namei(uchar, 2, 0); 294 if(pp == NULL) 295 return; 296 #ifdef EFS 297 /* divert to extended file system if off machine. */ 298 if (efsinode(pp)) { 299 dev_t ndev = pp->i_rdev; 300 301 iput(pp); /* avoid recursive hang on inode */ 302 efsunlink(ndev); 303 if (u.u_error != EEXIST) 304 return; 305 306 /* 307 * If a null pathname remainder, then do 308 * the unlink locally after restoring state. 309 */ 310 u.u_error = 0; 311 u.u_dirp = (caddr_t)u.u_arg[0]; 312 pp = namei(uchar, 2, 0); 313 } 314 #endif 315 316 /* 317 * Check for unlink(".") 318 * to avoid hanging on the iget 319 */ 320 if (pp->i_number == u.u_dent.d_ino) { 321 ip = pp; 322 ip->i_count++; 323 unlinkingdot++; 324 } else 325 ip = iget(pp->i_dev, pp->i_fs, u.u_dent.d_ino); 326 if(ip == NULL) 327 goto out1; 328 if((ip->i_mode&IFMT)==IFDIR && !suser()) 329 goto out; 330 /* 331 * Don't unlink a mounted file. 332 */ 333 if (ip->i_dev != pp->i_dev) { 334 u.u_error = EBUSY; 335 goto out; 336 } 337 if (ip->i_flag&ITEXT) 338 xrele(ip); /* try once to free text */ 339 /* 340 if ((ip->i_flag&ITEXT) && ip->i_nlink==1) { 341 u.u_error = ETXTBSY; 342 goto out; 343 } 344 */ 345 if (u.u_count == 0) { 346 /* 347 * first entry in block, so set d_ino to zero. 348 */ 349 u.u_base = (caddr_t)&u.u_dent; 350 u.u_count = DIRSIZ(&u.u_dent); 351 u.u_dent.d_ino = 0; 352 writei(pp); 353 } else { 354 /* 355 * updating preceeding entry to skip over current entry. 356 */ 357 fs = pp->i_fs; 358 lbn = lblkno(fs, u.u_offset); 359 base = blkoff(fs, u.u_offset); 360 bn = fsbtodb(fs, bmap(pp, lbn, B_WRITE, base + u.u_count)); 361 bp = bread(pp->i_dev, bn, blksize(fs, pp, lbn)); 362 if (bp->b_flags & B_ERROR) { 363 brelse(bp); 364 goto out; 365 } 366 ((struct direct *)(bp->b_un.b_addr + base))->d_reclen += 367 u.u_dent.d_reclen; 368 bwrite(bp); 369 pp->i_flag |= IUPD|ICHG; 370 } 371 ip->i_nlink--; 372 ip->i_flag |= ICHG; 373 374 out: 375 if (unlinkingdot) 376 irele(ip); 377 else 378 iput(ip); 379 out1: 380 iput(pp); 381 } 382 383 /* 384 * Seek system call 385 */ 386 seek() 387 { 388 register struct file *fp; 389 register struct a { 390 int fdes; 391 off_t off; 392 int sbase; 393 } *uap; 394 395 uap = (struct a *)u.u_ap; 396 fp = getf(uap->fdes); 397 if (fp == NULL) 398 return; 399 if (fp->f_flag&FSOCKET) { 400 u.u_error = ESPIPE; 401 return; 402 } 403 if (uap->sbase == 1) 404 uap->off += fp->f_offset; 405 else if (uap->sbase == 2) { 406 #ifdef EFS 407 struct inode *ip = fp->f_inode; 408 uap->off += efsinode(ip) ? efsfilesize(fp) : ip->i_size; 409 #else 410 uap->off += fp->f_inode->i_size; 411 #endif 412 } 413 fp->f_offset = uap->off; 414 u.u_r.r_off = uap->off; 415 } 416 417 /* 418 * Access system call 419 */ 420 saccess() 421 { 422 register svuid, svgid; 423 register struct inode *ip; 424 register struct a { 425 char *fname; 426 int fmode; 427 } *uap; 428 429 uap = (struct a *)u.u_ap; 430 svuid = u.u_uid; 431 svgid = u.u_gid; 432 u.u_uid = u.u_ruid; 433 u.u_gid = u.u_rgid; 434 ip = namei(uchar, 0, 1); 435 #ifdef EFS 436 if (efsinode(ip)) { 437 dev_t ndev = ip->i_rdev; 438 439 iput(ip); 440 efssaccess(ndev); 441 if (u.u_error != EEXIST) 442 return; 443 u.u_error = 0; 444 u.u_dirp = (caddr_t)u.u_arg[0]; 445 ip = namei(uchar, 0, 1); 446 } 447 #endif 448 if (ip != NULL) { 449 if (uap->fmode&(IREAD>>6)) 450 (void) access(ip, IREAD); 451 if (uap->fmode&(IWRITE>>6)) 452 (void) access(ip, IWRITE); 453 if (uap->fmode&(IEXEC>>6)) 454 (void) access(ip, IEXEC); 455 iput(ip); 456 } 457 u.u_uid = svuid; 458 u.u_gid = svgid; 459 } 460 461 /* 462 * the fstat system call. 463 */ 464 fstat() 465 { 466 register struct file *fp; 467 register struct a { 468 int fdes; 469 struct stat *sb; 470 } *uap; 471 472 uap = (struct a *)u.u_ap; 473 fp = getf(uap->fdes); 474 if (fp == NULL) 475 return; 476 #ifdef EFS 477 if (efsinode(fp->f_inode)) { 478 efsfstat(fp->f_inode->i_rdev, fp); 479 return; 480 } 481 #endif 482 if (fp->f_flag & FSOCKET) 483 u.u_error = sostat(fp->f_socket, uap->sb); 484 else 485 stat1(fp->f_inode, uap->sb); 486 } 487 488 /* 489 * Stat system call. This version follows links. 490 */ 491 stat() 492 { 493 register struct inode *ip; 494 register struct a { 495 char *fname; 496 struct stat *sb; 497 } *uap; 498 499 uap = (struct a *)u.u_ap; 500 ip = namei(uchar, 0, 1); 501 if (ip == NULL) 502 return; 503 #ifdef EFS 504 if (efsinode(ip)) { 505 dev_t ndev = ip->i_rdev; 506 507 iput(ip); 508 efsstat(ndev); 509 if (u.u_error != EEXIST) 510 return; 511 u.u_error = 0; 512 u.u_dirp = (caddr_t)u.u_arg[0]; 513 ip = namei(uchar, 0, 1); 514 } 515 #endif 516 stat1(ip, uap->sb); 517 iput(ip); 518 } 519 520 /* 521 * Lstat system call. This version does not follow links. 522 */ 523 lstat() 524 { 525 register struct inode *ip; 526 register struct a { 527 char *fname; 528 struct stat *sb; 529 } *uap; 530 531 uap = (struct a *)u.u_ap; 532 ip = namei(uchar, 0, 0); 533 if (ip == NULL) 534 return; 535 #ifdef EFS 536 if (efsinode(ip)) { 537 dev_t ndev = ip->i_rdev; 538 539 iput(ip); 540 efslstat(ndev); 541 if (u.u_error != EEXIST) 542 return; 543 u.u_error = 0; 544 u.u_dirp = (caddr_t)u.u_arg[0]; 545 ip = namei(uchar, 0, 0); 546 } 547 #endif 548 stat1(ip, uap->sb); 549 iput(ip); 550 } 551 552 /* 553 * The basic routine for fstat and stat: 554 * get the inode and pass appropriate parts back. 555 */ 556 stat1(ip, ub) 557 register struct inode *ip; 558 struct stat *ub; 559 { 560 struct stat ds; 561 562 IUPDAT(ip, &time, &time, 0); 563 /* 564 * Copy from inode table 565 */ 566 ds.st_dev = ip->i_dev; 567 ds.st_ino = ip->i_number; 568 ds.st_mode = ip->i_mode; 569 ds.st_nlink = ip->i_nlink; 570 ds.st_uid = ip->i_uid; 571 ds.st_gid = ip->i_gid; 572 ds.st_rdev = (dev_t)ip->i_rdev; 573 ds.st_size = ip->i_size; 574 ds.st_atime = ip->i_atime; 575 ds.st_mtime = ip->i_mtime; 576 ds.st_ctime = ip->i_ctime; 577 ds.st_blksize = ip->i_fs->fs_bsize; 578 if (copyout((caddr_t)&ds, (caddr_t)ub, sizeof(ds)) < 0) 579 u.u_error = EFAULT; 580 } 581 582 /* 583 * Return target name of a symbolic link 584 */ 585 readlink() 586 { 587 register struct inode *ip; 588 register struct a { 589 char *name; 590 char *buf; 591 int count; 592 } *uap; 593 594 ip = namei(uchar, 0, 0); 595 if (ip == NULL) 596 return; 597 #ifdef EFS 598 if (efsinode(ip)) { 599 dev_t ndev = ip->i_rdev; 600 601 iput(ip); 602 efsreadlink(ndev); 603 if (u.u_error != EEXIST) 604 return; 605 u.u_error = 0; 606 u.u_dirp = (caddr_t)u.u_arg[0]; 607 ip = namei(uchar, 0, 0); 608 return (0); 609 } 610 #endif 611 if ((ip->i_mode&IFMT) != IFLNK) { 612 u.u_error = ENXIO; 613 goto out; 614 } 615 uap = (struct a *)u.u_ap; 616 u.u_offset = 0; 617 u.u_base = uap->buf; 618 u.u_count = uap->count; 619 u.u_segflg = 0; 620 readi(ip); 621 out: 622 iput(ip); 623 u.u_r.r_val1 = uap->count - u.u_count; 624 } 625 626 chmod() 627 { 628 register struct inode *ip; 629 register struct a { 630 char *fname; 631 int fmode; 632 } *uap; 633 634 uap = (struct a *)u.u_ap; 635 if ((ip = owner(1)) == NULL) 636 return; 637 #ifdef EFS 638 if (efsinode(ip)) { 639 dev_t ndev = ip->i_rdev; 640 641 iput(ip); 642 efschmod(ndev); 643 if (u.u_error != EEXIST) 644 return; 645 u.u_error = 0; 646 u.u_dirp = (caddr_t)u.u_arg[0]; 647 ip = owner(1); 648 } 649 #endif 650 ip->i_mode &= ~07777; 651 if (u.u_uid) { 652 uap->fmode &= ~ISVTX; 653 if (ip->i_gid >= NGRPS || 654 (u.u_grps[ip->i_gid/(sizeof(int)*8)] & 655 (1 << ip->i_gid%(sizeof(int)*8))) == 0) 656 uap->fmode &= ~ISGID; 657 #if MUSH 658 if (u.u_quota->q_syflags & QF_UMASK && u.u_uid != 0 && 659 (ip->i_mode & IFMT) != IFCHR) 660 uap->fmode &= ~u.u_cmask; 661 #endif 662 } 663 ip->i_mode |= uap->fmode&07777; 664 ip->i_flag |= ICHG; 665 if (ip->i_flag&ITEXT && (ip->i_mode&ISVTX)==0) 666 xrele(ip); 667 #ifdef MELB 668 if ((ip->i_mode & ISUID) && ip->i_uid == 0) 669 printf("%s: ino %d (%s) setuid root\n" 670 , getfs(ip->i_dev)->s_fsmnt 671 , ip->i_number 672 , u.u_dent.d_name 673 ); 674 #endif 675 iput(ip); 676 } 677 678 chown() 679 { 680 register struct inode *ip; 681 register struct a { 682 char *fname; 683 int uid; 684 int gid; 685 } *uap; 686 #if QUOTA 687 register long change; 688 #endif 689 690 uap = (struct a *)u.u_ap; 691 if (!suser() || (ip = owner(0)) == NULL) 692 return; 693 #ifdef EFS 694 if (efsinode(ip)) { 695 dev_t ndev = ip->i_rdev; 696 697 iput(ip); 698 efschown(ndev); 699 if (u.u_error != EEXIST) 700 return; 701 u.u_error = 0; 702 u.u_dirp = (caddr_t)u.u_arg[0]; 703 ip = owner(0); 704 } 705 #endif 706 #if QUOTA 707 /* 708 * This doesn't allow for holes in files (which hopefully don't 709 * happen often in files that we chown), and is not accurate anyway 710 * (eg: it totally ignores 3 level indir blk files - but hopefully 711 * noone who can make a file that big will have a quota) 712 */ 713 if (ip->i_uid == uap->uid) 714 change = 0; 715 else { 716 register struct fs *fs = ip->i_fs; 717 718 if (ip->i_size > (change = NDADDR * fs->fs_bsize)) { 719 register off_t size; 720 721 size = blkroundup(fs, ip->i_size) - change; 722 change += size; 723 change += fs->fs_bsize; 724 /* This assumes NIADDR <= 2 */ 725 if (size > NINDIR(fs) * fs->fs_bsize) 726 change += fs->fs_bsize; 727 } else 728 change = fragroundup(fs, ip->i_size); 729 change /= DEV_BSIZE; 730 } 731 chkdq(ip, -change, 1); 732 chkiq(ip->i_dev, ip, ip->i_uid, 1); 733 dqrele(ip->i_dquot); 734 #endif 735 /* 736 * keep uid/gid's in sane range - no err, so chown(file, uid, -1) 737 * will do something useful 738 */ 739 if (uap->uid >= 0 && uap->uid <= 32767) /* should have a const */ 740 ip->i_uid = uap->uid; 741 if (uap->gid >= 0 && uap->gid <= 32767) /* same here */ 742 ip->i_gid = uap->gid; 743 ip->i_flag |= ICHG; 744 if (u.u_ruid != 0) 745 ip->i_mode &= ~(ISUID|ISGID); 746 #if QUOTA 747 ip->i_dquot = inoquota(ip); 748 chkdq(ip, change, 1); 749 chkiq(ip->i_dev, NULL, uap->uid, 1); 750 #endif 751 iput(ip); 752 } 753 754 /* 755 * Set IUPD and IACC times on file. 756 * Can't set ICHG. 757 */ 758 utime() 759 { 760 register struct a { 761 char *fname; 762 time_t *tptr; 763 } *uap; 764 register struct inode *ip; 765 time_t tv[2]; 766 767 uap = (struct a *)u.u_ap; 768 if ((ip = owner(1)) == NULL) 769 return; 770 if (copyin((caddr_t)uap->tptr, (caddr_t)tv, sizeof(tv))) { 771 u.u_error = EFAULT; 772 } else { 773 #ifdef EFS 774 if (efsinode(ip)) { 775 dev_t ndev = ip->i_rdev; 776 777 iput(ip); 778 efsutime(ndev, uap->fname, tv); 779 if (u.u_error != EEXIST) 780 return; 781 u.u_error = 0; 782 u.u_dirp = (caddr_t)u.u_arg[0]; 783 ip = owner(1); 784 } 785 #endif 786 ip->i_flag |= IACC|IUPD|ICHG; 787 iupdat(ip, &tv[0], &tv[1], 0); 788 } 789 iput(ip); 790 } 791 792 sync() 793 { 794 795 update(0); 796 } 797