/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2019 Google LLC * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank * Copyright (c) 1995 Martin Husemann * Some structure declaration borrowed from Paul Popelka * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include "ext.h" #include "fsutil.h" #define SLOT_EMPTY 0x00 /* slot has never been used */ #define SLOT_E5 0x05 /* the real value is 0xe5 */ #define SLOT_DELETED 0xe5 /* file in this slot deleted */ #define ATTR_NORMAL 0x00 /* normal file */ #define ATTR_READONLY 0x01 /* file is readonly */ #define ATTR_HIDDEN 0x02 /* file is hidden */ #define ATTR_SYSTEM 0x04 /* file is a system file */ #define ATTR_VOLUME 0x08 /* entry is a volume label */ #define ATTR_DIRECTORY 0x10 /* entry is a directory name */ #define ATTR_ARCHIVE 0x20 /* file is new or modified */ #define ATTR_WIN95 0x0f /* long name record */ /* * This is the format of the contents of the deTime field in the direntry * structure. * We don't use bitfields because we don't know how compilers for * arbitrary machines will lay them out. */ #define DT_2SECONDS_MASK 0x1F /* seconds divided by 2 */ #define DT_2SECONDS_SHIFT 0 #define DT_MINUTES_MASK 0x7E0 /* minutes */ #define DT_MINUTES_SHIFT 5 #define DT_HOURS_MASK 0xF800 /* hours */ #define DT_HOURS_SHIFT 11 /* * This is the format of the contents of the deDate field in the direntry * structure. */ #define DD_DAY_MASK 0x1F /* day of month */ #define DD_DAY_SHIFT 0 #define DD_MONTH_MASK 0x1E0 /* month */ #define DD_MONTH_SHIFT 5 #define DD_YEAR_MASK 0xFE00 /* year - 1980 */ #define DD_YEAR_SHIFT 9 /* dir.c */ static struct dosDirEntry *newDosDirEntry(void); static void freeDosDirEntry(struct dosDirEntry *); static struct dirTodoNode *newDirTodo(void); static void freeDirTodo(struct dirTodoNode *); static char *fullpath(struct dosDirEntry *); static u_char calcShortSum(u_char *); static int delete(struct fat_descriptor *, cl_t, int, cl_t, int, int); static int removede(struct fat_descriptor *, u_char *, u_char *, cl_t, cl_t, cl_t, char *, int); static int checksize(struct fat_descriptor *, u_char *, struct dosDirEntry *); static int readDosDirSection(struct fat_descriptor *, struct dosDirEntry *); /* * Manage free dosDirEntry structures. */ static struct dosDirEntry *freede; static struct dosDirEntry * newDosDirEntry(void) { struct dosDirEntry *de; if (!(de = freede)) { if (!(de = malloc(sizeof(*de)))) return (NULL); } else freede = de->next; return de; } static void freeDosDirEntry(struct dosDirEntry *de) { de->next = freede; freede = de; } /* * The same for dirTodoNode structures. */ static struct dirTodoNode *freedt; static struct dirTodoNode * newDirTodo(void) { struct dirTodoNode *dt; if (!(dt = freedt)) { if (!(dt = malloc(sizeof(*dt)))) return 0; } else freedt = dt->next; return dt; } static void freeDirTodo(struct dirTodoNode *dt) { dt->next = freedt; freedt = dt; } /* * The stack of unread directories */ static struct dirTodoNode *pendingDirectories = NULL; /* * Return the full pathname for a directory entry. */ static char * fullpath(struct dosDirEntry *dir) { static char namebuf[MAXPATHLEN + 1]; char *cp, *np; int nl; cp = namebuf + sizeof namebuf; *--cp = '\0'; for(;;) { np = dir->lname[0] ? dir->lname : dir->name; nl = strlen(np); if (cp <= namebuf + 1 + nl) { *--cp = '?'; break; } cp -= nl; memcpy(cp, np, nl); dir = dir->parent; if (!dir) break; *--cp = '/'; } return cp; } /* * Calculate a checksum over an 8.3 alias name */ static inline u_char calcShortSum(u_char *p) { u_char sum = 0; int i; for (i = 0; i < 11; i++) { sum = (sum << 7)|(sum >> 1); /* rotate right */ sum += p[i]; } return sum; } /* * Global variables temporarily used during a directory scan */ static char longName[DOSLONGNAMELEN] = ""; static u_char *buffer = NULL; static u_char *delbuf = NULL; static struct dosDirEntry *rootDir; static struct dosDirEntry *lostDir; /* * Init internal state for a new directory scan. */ int resetDosDirSection(struct fat_descriptor *fat) { int rootdir_size, cluster_size; int ret = FSOK; size_t len; struct bootblock *boot; boot = fat_get_boot(fat); rootdir_size = boot->bpbRootDirEnts * 32; cluster_size = boot->bpbSecPerClust * boot->bpbBytesPerSec; if ((buffer = malloc(len = MAX(rootdir_size, cluster_size))) == NULL) { perr("No space for directory buffer (%zu)", len); return FSFATAL; } if ((delbuf = malloc(len = cluster_size)) == NULL) { free(buffer); perr("No space for directory delbuf (%zu)", len); return FSFATAL; } if ((rootDir = newDosDirEntry()) == NULL) { free(buffer); free(delbuf); perr("No space for directory entry"); return FSFATAL; } memset(rootDir, 0, sizeof *rootDir); if (boot->flags & FAT32) { if (!fat_is_cl_head(fat, boot->bpbRootClust)) { free(buffer); free(delbuf); pfatal("Root directory doesn't start a cluster chain"); return FSFATAL; } rootDir->head = boot->bpbRootClust; } return ret; } /* * Cleanup after a directory scan */ void finishDosDirSection(void) { struct dirTodoNode *p, *np; struct dosDirEntry *d, *nd; for (p = pendingDirectories; p; p = np) { np = p->next; freeDirTodo(p); } pendingDirectories = NULL; for (d = rootDir; d; d = nd) { if ((nd = d->child) != NULL) { d->child = 0; continue; } if (!(nd = d->next)) nd = d->parent; freeDosDirEntry(d); } rootDir = lostDir = NULL; free(buffer); free(delbuf); buffer = NULL; delbuf = NULL; } /* * Delete directory entries between startcl, startoff and endcl, endoff. */ static int delete(struct fat_descriptor *fat, cl_t startcl, int startoff, cl_t endcl, int endoff, int notlast) { u_char *s, *e; off_t off; int clsz, fd; struct bootblock *boot; boot = fat_get_boot(fat); fd = fat_get_fd(fat); clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec; s = delbuf + startoff; e = delbuf + clsz; while (fat_is_valid_cl(fat, startcl)) { if (startcl == endcl) { if (notlast) break; e = delbuf + endoff; } off = (startcl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; off *= boot->bpbBytesPerSec; if (lseek(fd, off, SEEK_SET) != off) { perr("Unable to lseek to %" PRId64, off); return FSFATAL; } if (read(fd, delbuf, clsz) != clsz) { perr("Unable to read directory"); return FSFATAL; } while (s < e) { *s = SLOT_DELETED; s += 32; } if (lseek(fd, off, SEEK_SET) != off) { perr("Unable to lseek to %" PRId64, off); return FSFATAL; } if (write(fd, delbuf, clsz) != clsz) { perr("Unable to write directory"); return FSFATAL; } if (startcl == endcl) break; startcl = fat_get_cl_next(fat, startcl); s = delbuf; } return FSOK; } static int removede(struct fat_descriptor *fat, u_char *start, u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type) { switch (type) { case 0: pwarn("Invalid long filename entry for %s\n", path); break; case 1: pwarn("Invalid long filename entry at end of directory %s\n", path); break; case 2: pwarn("Invalid long filename entry for volume label\n"); break; } if (ask(0, "Remove")) { if (startcl != curcl) { if (delete(fat, startcl, start - buffer, endcl, end - buffer, endcl == curcl) == FSFATAL) return FSFATAL; start = buffer; } /* startcl is < CLUST_FIRST for !FAT32 root */ if ((endcl == curcl) || (startcl < CLUST_FIRST)) for (; start < end; start += 32) *start = SLOT_DELETED; return FSDIRMOD; } return FSERROR; } /* * Check an in-memory file entry */ static int checksize(struct fat_descriptor *fat, u_char *p, struct dosDirEntry *dir) { int ret = FSOK; size_t chainsize; u_int64_t physicalSize; struct bootblock *boot; boot = fat_get_boot(fat); /* * Check size on ordinary files */ if (dir->head == CLUST_FREE) { physicalSize = 0; } else { if (!fat_is_valid_cl(fat, dir->head) || !fat_is_cl_head(fat, dir->head)) { pwarn("Directory entry %s of size %u referencing invalid cluster %u\n", fullpath(dir), dir->size, dir->head); if (ask(1, "Truncate")) { p[28] = p[29] = p[30] = p[31] = 0; p[26] = p[27] = 0; if (boot->ClustMask == CLUST32_MASK) p[20] = p[21] = 0; dir->size = 0; dir->head = CLUST_FREE; return FSDIRMOD; } else { return FSERROR; } } ret = checkchain(fat, dir->head, &chainsize); /* * Upon return, chainsize would hold the chain length * that checkchain() was able to validate, but if the user * refused the proposed repair, it would be unsafe to * proceed with directory entry fix, so bail out in that * case. */ if (ret == FSERROR) { return (FSERROR); } /* * The maximum file size on FAT32 is 4GiB - 1, which * will occupy a cluster chain of exactly 4GiB in * size. On 32-bit platforms, since size_t is 32-bit, * it would wrap back to 0. */ physicalSize = (u_int64_t)chainsize * boot->ClusterSize; } if (physicalSize < dir->size) { pwarn("size of %s is %u, should at most be %ju\n", fullpath(dir), dir->size, (uintmax_t)physicalSize); if (ask(1, "Truncate")) { dir->size = physicalSize; p[28] = (u_char)physicalSize; p[29] = (u_char)(physicalSize >> 8); p[30] = (u_char)(physicalSize >> 16); p[31] = (u_char)(physicalSize >> 24); return FSDIRMOD; } else return FSERROR; } else if (physicalSize - dir->size >= boot->ClusterSize) { pwarn("%s has too many clusters allocated\n", fullpath(dir)); if (ask(1, "Drop superfluous clusters")) { cl_t cl; uint32_t sz, len; for (cl = dir->head, len = sz = 0; (sz += boot->ClusterSize) < dir->size; len++) cl = fat_get_cl_next(fat, cl); clearchain(fat, fat_get_cl_next(fat, cl)); ret = fat_set_cl_next(fat, cl, CLUST_EOF); return (FSFATMOD | ret); } else return FSERROR; } return FSOK; } static const u_char dot_name[11] = ". "; static const u_char dotdot_name[11] = ".. "; /* * Basic sanity check if the subdirectory have good '.' and '..' entries, * and they are directory entries. Further sanity checks are performed * when we traverse into it. */ static int check_subdirectory(struct fat_descriptor *fat, struct dosDirEntry *dir) { u_char *buf, *cp; off_t off; cl_t cl; int retval = FSOK; int fd; struct bootblock *boot; boot = fat_get_boot(fat); fd = fat_get_fd(fat); cl = dir->head; if (dir->parent && !fat_is_valid_cl(fat, cl)) { return FSERROR; } if (!(boot->flags & FAT32) && !dir->parent) { off = boot->bpbResSectors + boot->bpbFATs * boot->FATsecs; } else { off = (cl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; } /* * We only need to check the first two entries of the directory, * which is found in the first sector of the directory entry, * so read in only the first sector. */ buf = malloc(boot->bpbBytesPerSec); if (buf == NULL) { perr("No space for directory buffer (%u)", boot->bpbBytesPerSec); return FSFATAL; } off *= boot->bpbBytesPerSec; if (lseek(fd, off, SEEK_SET) != off || read(fd, buf, boot->bpbBytesPerSec) != (ssize_t)boot->bpbBytesPerSec) { perr("Unable to read directory"); free(buf); return FSFATAL; } /* * Both `.' and `..' must be present and be the first two entries * and be ATTR_DIRECTORY of a valid subdirectory. */ cp = buf; if (memcmp(cp, dot_name, sizeof(dot_name)) != 0 || (cp[11] & ATTR_DIRECTORY) != ATTR_DIRECTORY) { pwarn("%s: Incorrect `.' for %s.\n", __func__, dir->name); retval |= FSERROR; } cp += 32; if (memcmp(cp, dotdot_name, sizeof(dotdot_name)) != 0 || (cp[11] & ATTR_DIRECTORY) != ATTR_DIRECTORY) { pwarn("%s: Incorrect `..' for %s. \n", __func__, dir->name); retval |= FSERROR; } free(buf); return retval; } /* * Read a directory and * - resolve long name records * - enter file and directory records into the parent's list * - push directories onto the todo-stack */ static int readDosDirSection(struct fat_descriptor *fat, struct dosDirEntry *dir) { struct bootblock *boot; struct dosDirEntry dirent, *d; u_char *p, *vallfn, *invlfn, *empty; off_t off; int fd, i, j, k, iosize, entries; bool is_legacyroot; cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0; char *t; u_int lidx = 0; int shortSum; int mod = FSOK; size_t dirclusters; #define THISMOD 0x8000 /* Only used within this routine */ boot = fat_get_boot(fat); fd = fat_get_fd(fat); cl = dir->head; if (dir->parent && (!fat_is_valid_cl(fat, cl))) { /* * Already handled somewhere else. */ return FSOK; } shortSum = -1; vallfn = invlfn = empty = NULL; /* * If we are checking the legacy root (for FAT12/FAT16), * we will operate on the whole directory; otherwise, we * will operate on one cluster at a time, and also take * this opportunity to examine the chain. * * Derive how many entries we are going to encounter from * the I/O size. */ is_legacyroot = (dir->parent == NULL && !(boot->flags & FAT32)); if (is_legacyroot) { iosize = boot->bpbRootDirEnts * 32; entries = boot->bpbRootDirEnts; } else { iosize = boot->bpbSecPerClust * boot->bpbBytesPerSec; entries = iosize / 32; mod |= checkchain(fat, dir->head, &dirclusters); } do { if (is_legacyroot) { /* * Special case for FAT12/FAT16 root -- read * in the whole root directory. */ off = boot->bpbResSectors + boot->bpbFATs * boot->FATsecs; } else { /* * Otherwise, read in a cluster of the * directory. */ off = (cl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; } off *= boot->bpbBytesPerSec; if (lseek(fd, off, SEEK_SET) != off || read(fd, buffer, iosize) != iosize) { perr("Unable to read directory"); return FSFATAL; } for (p = buffer, i = 0; i < entries; i++, p += 32) { if (dir->fsckflags & DIREMPWARN) { *p = SLOT_EMPTY; continue; } if (*p == SLOT_EMPTY || *p == SLOT_DELETED) { if (*p == SLOT_EMPTY) { dir->fsckflags |= DIREMPTY; empty = p; empcl = cl; } continue; } if (dir->fsckflags & DIREMPTY) { if (!(dir->fsckflags & DIREMPWARN)) { pwarn("%s has entries after end of directory\n", fullpath(dir)); if (ask(1, "Extend")) { u_char *q; dir->fsckflags &= ~DIREMPTY; if (delete(fat, empcl, empty - buffer, cl, p - buffer, 1) == FSFATAL) return FSFATAL; q = ((empcl == cl) ? empty : buffer); assert(q != NULL); for (; q < p; q += 32) *q = SLOT_DELETED; mod |= THISMOD|FSDIRMOD; } else if (ask(0, "Truncate")) dir->fsckflags |= DIREMPWARN; } if (dir->fsckflags & DIREMPWARN) { *p = SLOT_DELETED; mod |= THISMOD|FSDIRMOD; continue; } else if (dir->fsckflags & DIREMPTY) mod |= FSERROR; empty = NULL; } if (p[11] == ATTR_WIN95) { if (*p & LRFIRST) { if (shortSum != -1) { if (!invlfn) { invlfn = vallfn; invcl = valcl; } } memset(longName, 0, sizeof longName); shortSum = p[13]; vallfn = p; valcl = cl; } else if (shortSum != p[13] || lidx != (*p & LRNOMASK)) { if (!invlfn) { invlfn = vallfn; invcl = valcl; } if (!invlfn) { invlfn = p; invcl = cl; } vallfn = NULL; } lidx = *p & LRNOMASK; if (lidx == 0) { pwarn("invalid long name\n"); if (!invlfn) { invlfn = vallfn; invcl = valcl; } vallfn = NULL; continue; } t = longName + --lidx * 13; for (k = 1; k < 11 && t < longName + sizeof(longName); k += 2) { if (!p[k] && !p[k + 1]) break; *t++ = p[k]; /* * Warn about those unusable chars in msdosfs here? XXX */ if (p[k + 1]) t[-1] = '?'; } if (k >= 11) for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) { if (!p[k] && !p[k + 1]) break; *t++ = p[k]; if (p[k + 1]) t[-1] = '?'; } if (k >= 26) for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) { if (!p[k] && !p[k + 1]) break; *t++ = p[k]; if (p[k + 1]) t[-1] = '?'; } if (t >= longName + sizeof(longName)) { pwarn("long filename too long\n"); if (!invlfn) { invlfn = vallfn; invcl = valcl; } vallfn = NULL; } if (p[26] | (p[27] << 8)) { pwarn("long filename record cluster start != 0\n"); if (!invlfn) { invlfn = vallfn; invcl = cl; } vallfn = NULL; } continue; /* long records don't carry further * information */ } /* * This is a standard msdosfs directory entry. */ memset(&dirent, 0, sizeof dirent); /* * it's a short name record, but we need to know * more, so get the flags first. */ dirent.flags = p[11]; /* * Translate from 850 to ISO here XXX */ for (j = 0; j < 8; j++) dirent.name[j] = p[j]; dirent.name[8] = '\0'; for (k = 7; k >= 0 && dirent.name[k] == ' '; k--) dirent.name[k] = '\0'; if (k < 0 || dirent.name[k] != '\0') k++; if (dirent.name[0] == SLOT_E5) dirent.name[0] = 0xe5; if (dirent.flags & ATTR_VOLUME) { if (vallfn || invlfn) { mod |= removede(fat, invlfn ? invlfn : vallfn, p, invlfn ? invcl : valcl, -1, 0, fullpath(dir), 2); vallfn = NULL; invlfn = NULL; } continue; } if (p[8] != ' ') dirent.name[k++] = '.'; for (j = 0; j < 3; j++) dirent.name[k++] = p[j+8]; dirent.name[k] = '\0'; for (k--; k >= 0 && dirent.name[k] == ' '; k--) dirent.name[k] = '\0'; if (vallfn && shortSum != calcShortSum(p)) { if (!invlfn) { invlfn = vallfn; invcl = valcl; } vallfn = NULL; } dirent.head = p[26] | (p[27] << 8); if (boot->ClustMask == CLUST32_MASK) dirent.head |= (p[20] << 16) | (p[21] << 24); dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24); if (vallfn) { strlcpy(dirent.lname, longName, sizeof(dirent.lname)); longName[0] = '\0'; shortSum = -1; } dirent.parent = dir; dirent.next = dir->child; if (invlfn) { mod |= k = removede(fat, invlfn, vallfn ? vallfn : p, invcl, vallfn ? valcl : cl, cl, fullpath(&dirent), 0); if (mod & FSFATAL) return FSFATAL; if (vallfn ? (valcl == cl && vallfn != buffer) : p != buffer) if (k & FSDIRMOD) mod |= THISMOD; } vallfn = NULL; /* not used any longer */ invlfn = NULL; /* * Check if the directory entry is sane. * * '.' and '..' are skipped, their sanity is * checked somewhere else. * * For everything else, check if we have a new, * valid cluster chain (beginning of a file or * directory that was never previously claimed * by another file) when it's a non-empty file * or a directory. The sanity of the cluster * chain is checked at a later time when we * traverse into the directory, or examine the * file's directory entry. * * The only possible fix is to delete the entry * if it's a directory; for file, we have to * truncate the size to 0. */ if (!(dirent.flags & ATTR_DIRECTORY) || (strcmp(dirent.name, ".") != 0 && strcmp(dirent.name, "..") != 0)) { if ((dirent.size != 0 || (dirent.flags & ATTR_DIRECTORY)) && ((!fat_is_valid_cl(fat, dirent.head) || !fat_is_cl_head(fat, dirent.head)))) { if (!fat_is_valid_cl(fat, dirent.head)) { pwarn("%s starts with cluster out of range(%u)\n", fullpath(&dirent), dirent.head); } else { pwarn("%s doesn't start a new cluster chain\n", fullpath(&dirent)); } if (dirent.flags & ATTR_DIRECTORY) { if (ask(0, "Remove")) { *p = SLOT_DELETED; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; continue; } else { if (ask(1, "Truncate")) { p[28] = p[29] = p[30] = p[31] = 0; p[26] = p[27] = 0; if (boot->ClustMask == CLUST32_MASK) p[20] = p[21] = 0; dirent.size = 0; dirent.head = 0; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; } } } if (dirent.flags & ATTR_DIRECTORY) { /* * gather more info for directories */ struct dirTodoNode *n; if (dirent.size) { pwarn("Directory %s has size != 0\n", fullpath(&dirent)); if (ask(1, "Correct")) { p[28] = p[29] = p[30] = p[31] = 0; dirent.size = 0; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; } /* * handle `.' and `..' specially */ if (strcmp(dirent.name, ".") == 0) { if (dirent.head != dir->head) { pwarn("`.' entry in %s has incorrect start cluster\n", fullpath(dir)); if (ask(1, "Correct")) { dirent.head = dir->head; p[26] = (u_char)dirent.head; p[27] = (u_char)(dirent.head >> 8); if (boot->ClustMask == CLUST32_MASK) { p[20] = (u_char)(dirent.head >> 16); p[21] = (u_char)(dirent.head >> 24); } mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; } continue; } else if (strcmp(dirent.name, "..") == 0) { if (dir->parent) { /* XXX */ if (!dir->parent->parent) { if (dirent.head) { pwarn("`..' entry in %s has non-zero start cluster\n", fullpath(dir)); if (ask(1, "Correct")) { dirent.head = 0; p[26] = p[27] = 0; if (boot->ClustMask == CLUST32_MASK) p[20] = p[21] = 0; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; } } else if (dirent.head != dir->parent->head) { pwarn("`..' entry in %s has incorrect start cluster\n", fullpath(dir)); if (ask(1, "Correct")) { dirent.head = dir->parent->head; p[26] = (u_char)dirent.head; p[27] = (u_char)(dirent.head >> 8); if (boot->ClustMask == CLUST32_MASK) { p[20] = (u_char)(dirent.head >> 16); p[21] = (u_char)(dirent.head >> 24); } mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; } } continue; } else { /* * Only one directory entry can point * to dir->head, it's '.'. */ if (dirent.head == dir->head) { pwarn("%s entry in %s has incorrect start cluster\n", dirent.name, fullpath(dir)); if (ask(1, "Remove")) { *p = SLOT_DELETED; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; continue; } else if ((check_subdirectory(fat, &dirent) & FSERROR) == FSERROR) { /* * A subdirectory should have * a dot (.) entry and a dot-dot * (..) entry of ATTR_DIRECTORY, * we will inspect further when * traversing into it. */ if (ask(1, "Remove")) { *p = SLOT_DELETED; mod |= THISMOD|FSDIRMOD; } else mod |= FSERROR; continue; } } /* create directory tree node */ if (!(d = newDosDirEntry())) { perr("No space for directory"); return FSFATAL; } memcpy(d, &dirent, sizeof(struct dosDirEntry)); /* link it into the tree */ dir->child = d; /* Enter this directory into the todo list */ if (!(n = newDirTodo())) { perr("No space for todo list"); return FSFATAL; } n->next = pendingDirectories; n->dir = d; pendingDirectories = n; } else { mod |= k = checksize(fat, p, &dirent); if (k & FSDIRMOD) mod |= THISMOD; } boot->NumFiles++; } if (is_legacyroot) { /* * Don't bother to write back right now because * we may continue to make modification to the * non-FAT32 root directory below. */ break; } else if (mod & THISMOD) { if (lseek(fd, off, SEEK_SET) != off || write(fd, buffer, iosize) != iosize) { perr("Unable to write directory"); return FSFATAL; } mod &= ~THISMOD; } } while (fat_is_valid_cl(fat, (cl = fat_get_cl_next(fat, cl)))); if (invlfn || vallfn) mod |= removede(fat, invlfn ? invlfn : vallfn, p, invlfn ? invcl : valcl, -1, 0, fullpath(dir), 1); /* * The root directory of non-FAT32 filesystems is in a special * area and may have been modified above removede() without * being written out. */ if ((mod & FSDIRMOD) && is_legacyroot) { if (lseek(fd, off, SEEK_SET) != off || write(fd, buffer, iosize) != iosize) { perr("Unable to write directory"); return FSFATAL; } mod &= ~THISMOD; } return mod & ~THISMOD; } int handleDirTree(struct fat_descriptor *fat) { int mod; mod = readDosDirSection(fat, rootDir); if (mod & FSFATAL) return FSFATAL; /* * process the directory todo list */ while (pendingDirectories) { struct dosDirEntry *dir = pendingDirectories->dir; struct dirTodoNode *n = pendingDirectories->next; /* * remove TODO entry now, the list might change during * directory reads */ freeDirTodo(pendingDirectories); pendingDirectories = n; /* * handle subdirectory */ mod |= readDosDirSection(fat, dir); if (mod & FSFATAL) return FSFATAL; } return mod; } /* * Try to reconnect a FAT chain into dir */ static u_char *lfbuf; static cl_t lfcl; static off_t lfoff; int reconnect(struct fat_descriptor *fat, cl_t head, size_t length) { struct bootblock *boot = fat_get_boot(fat); struct dosDirEntry d; int len, dosfs; u_char *p; dosfs = fat_get_fd(fat); if (!ask(1, "Reconnect")) return FSERROR; if (!lostDir) { for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) { if (!strcmp(lostDir->name, LOSTDIR)) break; } if (!lostDir) { /* Create LOSTDIR? XXX */ pwarn("No %s directory\n", LOSTDIR); return FSERROR; } } if (!lfbuf) { lfbuf = malloc(boot->ClusterSize); if (!lfbuf) { perr("No space for buffer"); return FSFATAL; } p = NULL; } else p = lfbuf; while (1) { if (p) for (; p < lfbuf + boot->ClusterSize; p += 32) if (*p == SLOT_EMPTY || *p == SLOT_DELETED) break; if (p && p < lfbuf + boot->ClusterSize) break; lfcl = p ? fat_get_cl_next(fat, lfcl) : lostDir->head; if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) { /* Extend LOSTDIR? XXX */ pwarn("No space in %s\n", LOSTDIR); lfcl = (lostDir->head < boot->NumClusters) ? lostDir->head : 0; return FSERROR; } lfoff = (lfcl - CLUST_FIRST) * boot->ClusterSize + boot->FirstCluster * boot->bpbBytesPerSec; if (lseek(dosfs, lfoff, SEEK_SET) != lfoff || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) { perr("could not read LOST.DIR"); return FSFATAL; } p = lfbuf; } boot->NumFiles++; /* Ensure uniqueness of entry here! XXX */ memset(&d, 0, sizeof d); /* worst case -1 = 4294967295, 10 digits */ len = snprintf(d.name, sizeof(d.name), "%u", head); d.flags = 0; d.head = head; d.size = length * boot->ClusterSize; memcpy(p, d.name, len); memset(p + len, ' ', 11 - len); memset(p + 11, 0, 32 - 11); p[26] = (u_char)d.head; p[27] = (u_char)(d.head >> 8); if (boot->ClustMask == CLUST32_MASK) { p[20] = (u_char)(d.head >> 16); p[21] = (u_char)(d.head >> 24); } p[28] = (u_char)d.size; p[29] = (u_char)(d.size >> 8); p[30] = (u_char)(d.size >> 16); p[31] = (u_char)(d.size >> 24); if (lseek(dosfs, lfoff, SEEK_SET) != lfoff || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) { perr("could not write LOST.DIR"); return FSFATAL; } return FSDIRMOD; } void finishlf(void) { if (lfbuf) free(lfbuf); lfbuf = NULL; }