/*- * Copyright (c) 2003-2007 Tim Kientzle * All rights reserved. * * 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 * in this position and unchanged. * 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 AUTHOR(S) ``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 AUTHOR(S) 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 "archive_platform.h" __FBSDID("$FreeBSD$"); #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_ACL_H #include #endif #ifdef HAVE_ATTR_XATTR_H #include #endif #ifdef HAVE_SYS_IOCTL_H #include #endif #ifdef HAVE_SYS_STAT_H #include #endif #ifdef HAVE_SYS_TIME_H #include #endif #ifdef HAVE_SYS_UTIME_H #include #endif #ifdef HAVE_EXT2FS_EXT2_FS_H #include /* for Linux file flags */ #endif #ifdef HAVE_ERRNO_H #include #endif #ifdef HAVE_FCNTL_H #include #endif #ifdef HAVE_GRP_H #include #endif #ifdef HAVE_LINUX_FS_H #include /* for Linux file flags */ #endif #ifdef HAVE_LIMITS_H #include #endif #ifdef HAVE_PWD_H #include #endif #include #ifdef HAVE_STDLIB_H #include #endif #ifdef HAVE_STRING_H #include #endif #ifdef HAVE_UNISTD_H #include #endif #ifdef HAVE_UTIME_H #include #endif #include "archive.h" #include "archive_string.h" #include "archive_entry.h" #include "archive_private.h" #ifndef O_BINARY #define O_BINARY 0 #endif struct fixup_entry { struct fixup_entry *next; mode_t mode; int64_t mtime; int64_t atime; unsigned long mtime_nanos; unsigned long atime_nanos; unsigned long fflags_set; int fixup; /* bitmask of what needs fixing */ char *name; }; /* * We use a bitmask to track which operations remain to be done for * this file. In particular, this helps us avoid unnecessary * operations when it's possible to take care of one step as a * side-effect of another. For example, mkdir() can specify the mode * for the newly-created object but symlink() cannot. This means we * can skip chmod() if mkdir() succeeded, but we must explicitly * chmod() if we're trying to create a directory that already exists * (mkdir() failed) or if we're restoring a symlink. Similarly, we * need to verify UID/GID before trying to restore SUID/SGID bits; * that verification can occur explicitly through a stat() call or * implicitly because of a successful chown() call. */ #define TODO_MODE_FORCE 0x40000000 #define TODO_MODE_BASE 0x20000000 #define TODO_SUID 0x10000000 #define TODO_SUID_CHECK 0x08000000 #define TODO_SGID 0x04000000 #define TODO_SGID_CHECK 0x02000000 #define TODO_MODE (TODO_MODE_BASE|TODO_SUID|TODO_SGID) #define TODO_TIMES ARCHIVE_EXTRACT_TIME #define TODO_OWNER ARCHIVE_EXTRACT_OWNER #define TODO_FFLAGS ARCHIVE_EXTRACT_FFLAGS #define TODO_ACLS ARCHIVE_EXTRACT_ACL #define TODO_XATTR ARCHIVE_EXTRACT_XATTR struct archive_write_disk { struct archive archive; mode_t user_umask; struct fixup_entry *fixup_list; struct fixup_entry *current_fixup; uid_t user_uid; dev_t skip_file_dev; ino_t skip_file_ino; time_t start_time; gid_t (*lookup_gid)(void *private, const char *gname, gid_t gid); void (*cleanup_gid)(void *private); void *lookup_gid_data; uid_t (*lookup_uid)(void *private, const char *gname, gid_t gid); void (*cleanup_uid)(void *private); void *lookup_uid_data; /* * Full path of last file to satisfy symlink checks. */ struct archive_string path_safe; /* * Cached stat data from disk for the current entry. * If this is valid, pst points to st. Otherwise, * pst is null. */ struct stat st; struct stat *pst; /* Information about the object being restored right now. */ struct archive_entry *entry; /* Entry being extracted. */ char *name; /* Name of entry, possibly edited. */ struct archive_string _name_data; /* backing store for 'name' */ /* Tasks remaining for this object. */ int todo; /* Tasks deferred until end-of-archive. */ int deferred; /* Options requested by the client. */ int flags; /* Handle for the file we're restoring. */ int fd; /* Current offset for writing data to the file. */ off_t offset; /* Maximum size of file, -1 if unknown. */ off_t filesize; /* Dir we were in before this restore; only for deep paths. */ int restore_pwd; /* Mode we should use for this entry; affected by _PERM and umask. */ mode_t mode; /* UID/GID to use in restoring this entry. */ uid_t uid; gid_t gid; /* Last offset written to disk. */ off_t last_offset; }; /* * Default mode for dirs created automatically (will be modified by umask). * Note that POSIX specifies 0777 for implicity-created dirs, "modified * by the process' file creation mask." */ #define DEFAULT_DIR_MODE 0777 /* * Dir modes are restored in two steps: During the extraction, the permissions * in the archive are modified to match the following limits. During * the post-extract fixup pass, the permissions from the archive are * applied. */ #define MINIMUM_DIR_MODE 0700 #define MAXIMUM_DIR_MODE 0775 static int check_symlinks(struct archive_write_disk *); static int create_filesystem_object(struct archive_write_disk *); static struct fixup_entry *current_fixup(struct archive_write_disk *, const char *pathname); #ifdef HAVE_FCHDIR static void edit_deep_directories(struct archive_write_disk *ad); #endif static int cleanup_pathname(struct archive_write_disk *); static int create_dir(struct archive_write_disk *, char *); static int create_parent_dir(struct archive_write_disk *, char *); static int older(struct stat *, struct archive_entry *); static int restore_entry(struct archive_write_disk *); #ifdef HAVE_POSIX_ACL static int set_acl(struct archive_write_disk *, int fd, struct archive_entry *, acl_type_t, int archive_entry_acl_type, const char *tn); #endif static int set_acls(struct archive_write_disk *); static int set_xattrs(struct archive_write_disk *); static int set_fflags(struct archive_write_disk *); static int set_fflags_platform(struct archive_write_disk *, int fd, const char *name, mode_t mode, unsigned long fflags_set, unsigned long fflags_clear); static int set_ownership(struct archive_write_disk *); static int set_mode(struct archive_write_disk *, int mode); static int set_time(struct archive_write_disk *); static struct fixup_entry *sort_dir_list(struct fixup_entry *p); static gid_t trivial_lookup_gid(void *, const char *, gid_t); static uid_t trivial_lookup_uid(void *, const char *, uid_t); static ssize_t write_data_block(struct archive_write_disk *, const char *, size_t, off_t); static struct archive_vtable *archive_write_disk_vtable(void); static int _archive_write_close(struct archive *); static int _archive_write_finish(struct archive *); static int _archive_write_header(struct archive *, struct archive_entry *); static int _archive_write_finish_entry(struct archive *); static ssize_t _archive_write_data(struct archive *, const void *, size_t); static ssize_t _archive_write_data_block(struct archive *, const void *, size_t, off_t); static int _archive_write_disk_lazy_stat(struct archive_write_disk *a) { if (a->pst != NULL) { /* Already have stat() data available. */ return (ARCHIVE_OK); } #ifdef HAVE_FSTAT if (a->fd >= 0 && fstat(a->fd, &a->st) == 0) { a->pst = &a->st; return (ARCHIVE_OK); } #endif /* * XXX At this point, symlinks should not be hit, otherwise * XXX a race occured. Do we want to check explicitly for that? */ if (lstat(a->name, &a->st) == 0) { a->pst = &a->st; return (ARCHIVE_OK); } archive_set_error(&a->archive, errno, "Couldn't stat file"); return (ARCHIVE_WARN); } static struct archive_vtable * archive_write_disk_vtable(void) { static struct archive_vtable av; static int inited = 0; if (!inited) { av.archive_write_close = _archive_write_close; av.archive_write_finish = _archive_write_finish; av.archive_write_header = _archive_write_header; av.archive_write_finish_entry = _archive_write_finish_entry; av.archive_write_data = _archive_write_data; av.archive_write_data_block = _archive_write_data_block; } return (&av); } int archive_write_disk_set_options(struct archive *_a, int flags) { struct archive_write_disk *a = (struct archive_write_disk *)_a; a->flags = flags; return (ARCHIVE_OK); } /* * Extract this entry to disk. * * TODO: Validate hardlinks. According to the standards, we're * supposed to check each extracted hardlink and squawk if it refers * to a file that we didn't restore. I'm not entirely convinced this * is a good idea, but more importantly: Is there any way to validate * hardlinks without keeping a complete list of filenames from the * entire archive?? Ugh. * */ static int _archive_write_header(struct archive *_a, struct archive_entry *entry) { struct archive_write_disk *a = (struct archive_write_disk *)_a; struct fixup_entry *fe; int ret, r; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA, "archive_write_disk_header"); archive_clear_error(&a->archive); if (a->archive.state & ARCHIVE_STATE_DATA) { r = _archive_write_finish_entry(&a->archive); if (r == ARCHIVE_FATAL) return (r); } /* Set up for this particular entry. */ a->pst = NULL; a->current_fixup = NULL; a->deferred = 0; if (a->entry) { archive_entry_free(a->entry); a->entry = NULL; } a->entry = archive_entry_clone(entry); a->fd = -1; a->last_offset = 0; a->offset = 0; a->uid = a->user_uid; a->mode = archive_entry_mode(a->entry); if (archive_entry_size_is_set(a->entry)) a->filesize = archive_entry_size(a->entry); else a->filesize = -1; archive_strcpy(&(a->_name_data), archive_entry_pathname(a->entry)); a->name = a->_name_data.s; archive_clear_error(&a->archive); /* * Clean up the requested path. This is necessary for correct * dir restores; the dir restore logic otherwise gets messed * up by nonsense like "dir/.". */ ret = cleanup_pathname(a); if (ret != ARCHIVE_OK) return (ret); /* * Set the umask to zero so we get predictable mode settings. * This gets done on every call to _write_header in case the * user edits their umask during the extraction for some * reason. This will be reset before we return. Note that we * don't need to do this in _finish_entry, as the chmod(), etc, * system calls don't obey umask. */ a->user_umask = umask(0); /* From here on, early exit requires "goto done" to clean up. */ /* Figure out what we need to do for this entry. */ a->todo = TODO_MODE_BASE; if (a->flags & ARCHIVE_EXTRACT_PERM) { a->todo |= TODO_MODE_FORCE; /* Be pushy about permissions. */ /* * SGID requires an extra "check" step because we * cannot easily predict the GID that the system will * assign. (Different systems assign GIDs to files * based on a variety of criteria, including process * credentials and the gid of the enclosing * directory.) We can only restore the SGID bit if * the file has the right GID, and we only know the * GID if we either set it (see set_ownership) or if * we've actually called stat() on the file after it * was restored. Since there are several places at * which we might verify the GID, we need a TODO bit * to keep track. */ if (a->mode & S_ISGID) a->todo |= TODO_SGID | TODO_SGID_CHECK; /* * Verifying the SUID is simpler, but can still be * done in multiple ways, hence the separate "check" bit. */ if (a->mode & S_ISUID) a->todo |= TODO_SUID | TODO_SUID_CHECK; } else { /* * User didn't request full permissions, so don't * restore SUID, SGID bits and obey umask. */ a->mode &= ~S_ISUID; a->mode &= ~S_ISGID; a->mode &= ~S_ISVTX; a->mode &= ~a->user_umask; } if (a->flags & ARCHIVE_EXTRACT_OWNER) a->todo |= TODO_OWNER; if (a->flags & ARCHIVE_EXTRACT_TIME) a->todo |= TODO_TIMES; if (a->flags & ARCHIVE_EXTRACT_ACL) a->todo |= TODO_ACLS; if (a->flags & ARCHIVE_EXTRACT_FFLAGS) a->todo |= TODO_FFLAGS; if (a->flags & ARCHIVE_EXTRACT_SECURE_SYMLINKS) { ret = check_symlinks(a); if (ret != ARCHIVE_OK) goto done; } #ifdef HAVE_FCHDIR /* If path exceeds PATH_MAX, shorten the path. */ edit_deep_directories(a); #endif ret = restore_entry(a); #ifdef HAVE_FCHDIR /* If we changed directory above, restore it here. */ if (a->restore_pwd >= 0) { fchdir(a->restore_pwd); close(a->restore_pwd); a->restore_pwd = -1; } #endif /* * Fixup uses the unedited pathname from archive_entry_pathname(), * because it is relative to the base dir and the edited path * might be relative to some intermediate dir as a result of the * deep restore logic. */ if (a->deferred & TODO_MODE) { fe = current_fixup(a, archive_entry_pathname(entry)); fe->fixup |= TODO_MODE_BASE; fe->mode = a->mode; } if ((a->deferred & TODO_TIMES) && (archive_entry_mtime_is_set(entry) || archive_entry_atime_is_set(entry))) { fe = current_fixup(a, archive_entry_pathname(entry)); fe->fixup |= TODO_TIMES; if (archive_entry_mtime_is_set(entry)) { fe->mtime = archive_entry_mtime(entry); fe->mtime_nanos = archive_entry_mtime_nsec(entry); } else { fe->mtime = a->start_time; fe->mtime_nanos = 0; } if (archive_entry_atime_is_set(entry)) { fe->atime = archive_entry_atime(entry); fe->atime_nanos = archive_entry_atime_nsec(entry); } else { fe->atime = a->start_time; fe->atime_nanos = 0; } } if (a->deferred & TODO_FFLAGS) { fe = current_fixup(a, archive_entry_pathname(entry)); fe->fixup |= TODO_FFLAGS; /* TODO: Complete this.. defer fflags from below. */ } /* We've created the object and are ready to pour data into it. */ if (ret == ARCHIVE_OK) a->archive.state = ARCHIVE_STATE_DATA; /* * If it's not open, tell our client not to try writing. * In particular, dirs, links, etc, don't get written to. */ if (a->fd < 0) { archive_entry_set_size(entry, 0); a->filesize = 0; } done: /* Restore the user's umask before returning. */ umask(a->user_umask); return (ret); } int archive_write_disk_set_skip_file(struct archive *_a, dev_t d, ino_t i) { struct archive_write_disk *a = (struct archive_write_disk *)_a; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_ANY, "archive_write_disk_set_skip_file"); a->skip_file_dev = d; a->skip_file_ino = i; return (ARCHIVE_OK); } static ssize_t write_data_block(struct archive_write_disk *a, const char *buff, size_t size, off_t offset) { ssize_t bytes_written = 0; ssize_t block_size = 0, bytes_to_write; int r; if (a->filesize == 0 || a->fd < 0) { archive_set_error(&a->archive, 0, "Attempt to write to an empty file"); return (ARCHIVE_WARN); } if (a->flags & ARCHIVE_EXTRACT_SPARSE) { if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK) return (r); block_size = a->pst->st_blksize; } if (a->filesize >= 0 && (off_t)(offset + size) > a->filesize) size = (size_t)(a->filesize - offset); /* Write the data. */ while (size > 0) { if (block_size == 0) { bytes_to_write = size; } else { /* We're sparsifying the file. */ const char *p, *end; off_t block_end; /* Skip leading zero bytes. */ for (p = buff, end = buff + size; p < end; ++p) { if (*p != '\0') break; } offset += p - buff; size -= p - buff; buff = p; if (size == 0) break; /* Calculate next block boundary after offset. */ block_end = (offset / block_size) * block_size + block_size; /* If the adjusted write would cross block boundary, * truncate it to the block boundary. */ bytes_to_write = size; if (offset + bytes_to_write > block_end) bytes_to_write = block_end - offset; } /* Seek if necessary to the specified offset. */ if (offset != a->last_offset) { if (lseek(a->fd, offset, SEEK_SET) < 0) { archive_set_error(&a->archive, errno, "Seek failed"); return (ARCHIVE_FATAL); } } bytes_written = write(a->fd, buff, bytes_to_write); if (bytes_written < 0) { archive_set_error(&a->archive, errno, "Write failed"); return (ARCHIVE_WARN); } buff += bytes_written; size -= bytes_written; offset += bytes_written; a->archive.file_position += bytes_written; a->archive.raw_position += bytes_written; a->last_offset = a->offset = offset; } return (bytes_written); } static ssize_t _archive_write_data_block(struct archive *_a, const void *buff, size_t size, off_t offset) { struct archive_write_disk *a = (struct archive_write_disk *)_a; ssize_t r; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_DATA, "archive_write_disk_block"); r = write_data_block(a, buff, size, offset); if (r < 0) return (r); if ((size_t)r < size) { archive_set_error(&a->archive, 0, "Write request too large"); return (ARCHIVE_WARN); } return (ARCHIVE_OK); } static ssize_t _archive_write_data(struct archive *_a, const void *buff, size_t size) { struct archive_write_disk *a = (struct archive_write_disk *)_a; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_DATA, "archive_write_data"); return (write_data_block(a, buff, size, a->offset)); } static int _archive_write_finish_entry(struct archive *_a) { struct archive_write_disk *a = (struct archive_write_disk *)_a; int ret = ARCHIVE_OK; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA, "archive_write_finish_entry"); if (a->archive.state & ARCHIVE_STATE_HEADER) return (ARCHIVE_OK); archive_clear_error(&a->archive); /* Pad or truncate file to the right size. */ if (a->fd < 0) { /* There's no file. */ } else if (a->filesize < 0) { /* File size is unknown, so we can't set the size. */ } else if (a->last_offset == a->filesize) { /* Last write ended at exactly the filesize; we're done. */ /* Hopefully, this is the common case. */ } else { if (ftruncate(a->fd, a->filesize) == -1 && a->filesize == 0) { archive_set_error(&a->archive, errno, "File size could not be restored"); return (ARCHIVE_FAILED); } /* * Explicitly stat the file as some platforms might not * implement the XSI option to extend files via ftruncate. */ a->pst = NULL; if ((ret = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK) return (ret); if (a->st.st_size != a->filesize) { const char nul = '\0'; if (lseek(a->fd, a->st.st_size - 1, SEEK_SET) < 0) { archive_set_error(&a->archive, errno, "Seek failed"); return (ARCHIVE_FATAL); } if (write(a->fd, &nul, 1) < 0) { archive_set_error(&a->archive, errno, "Write to restore size failed"); return (ARCHIVE_FATAL); } a->pst = NULL; } } /* Restore metadata. */ /* * Look up the "real" UID only if we're going to need it. * TODO: the TODO_SGID condition can be dropped here, can't it? */ if (a->todo & (TODO_OWNER | TODO_SUID | TODO_SGID)) { a->uid = a->lookup_uid(a->lookup_uid_data, archive_entry_uname(a->entry), archive_entry_uid(a->entry)); } /* Look up the "real" GID only if we're going to need it. */ /* TODO: the TODO_SUID condition can be dropped here, can't it? */ if (a->todo & (TODO_OWNER | TODO_SGID | TODO_SUID)) { a->gid = a->lookup_gid(a->lookup_gid_data, archive_entry_gname(a->entry), archive_entry_gid(a->entry)); } /* * If restoring ownership, do it before trying to restore suid/sgid * bits. If we set the owner, we know what it is and can skip * a stat() call to examine the ownership of the file on disk. */ if (a->todo & TODO_OWNER) ret = set_ownership(a); if (a->todo & TODO_MODE) { int r2 = set_mode(a, a->mode); if (r2 < ret) ret = r2; } if (a->todo & TODO_TIMES) { int r2 = set_time(a); if (r2 < ret) ret = r2; } if (a->todo & TODO_ACLS) { int r2 = set_acls(a); if (r2 < ret) ret = r2; } if (a->todo & TODO_XATTR) { int r2 = set_xattrs(a); if (r2 < ret) ret = r2; } if (a->todo & TODO_FFLAGS) { int r2 = set_fflags(a); if (r2 < ret) ret = r2; } /* If there's an fd, we can close it now. */ if (a->fd >= 0) { close(a->fd); a->fd = -1; } /* If there's an entry, we can release it now. */ if (a->entry) { archive_entry_free(a->entry); a->entry = NULL; } a->archive.state = ARCHIVE_STATE_HEADER; return (ret); } int archive_write_disk_set_group_lookup(struct archive *_a, void *private_data, gid_t (*lookup_gid)(void *private, const char *gname, gid_t gid), void (*cleanup_gid)(void *private)) { struct archive_write_disk *a = (struct archive_write_disk *)_a; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_ANY, "archive_write_disk_set_group_lookup"); a->lookup_gid = lookup_gid; a->cleanup_gid = cleanup_gid; a->lookup_gid_data = private_data; return (ARCHIVE_OK); } int archive_write_disk_set_user_lookup(struct archive *_a, void *private_data, uid_t (*lookup_uid)(void *private, const char *uname, uid_t uid), void (*cleanup_uid)(void *private)) { struct archive_write_disk *a = (struct archive_write_disk *)_a; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_ANY, "archive_write_disk_set_user_lookup"); a->lookup_uid = lookup_uid; a->cleanup_uid = cleanup_uid; a->lookup_uid_data = private_data; return (ARCHIVE_OK); } /* * Create a new archive_write_disk object and initialize it with global state. */ struct archive * archive_write_disk_new(void) { struct archive_write_disk *a; a = (struct archive_write_disk *)malloc(sizeof(*a)); if (a == NULL) return (NULL); memset(a, 0, sizeof(*a)); a->archive.magic = ARCHIVE_WRITE_DISK_MAGIC; /* We're ready to write a header immediately. */ a->archive.state = ARCHIVE_STATE_HEADER; a->archive.vtable = archive_write_disk_vtable(); a->lookup_uid = trivial_lookup_uid; a->lookup_gid = trivial_lookup_gid; a->start_time = time(NULL); #ifdef HAVE_GETEUID a->user_uid = geteuid(); #endif /* HAVE_GETEUID */ if (archive_string_ensure(&a->path_safe, 512) == NULL) { free(a); return (NULL); } return (&a->archive); } /* * If pathname is longer than PATH_MAX, chdir to a suitable * intermediate dir and edit the path down to a shorter suffix. Note * that this routine never returns an error; if the chdir() attempt * fails for any reason, we just go ahead with the long pathname. The * object creation is likely to fail, but any error will get handled * at that time. */ #ifdef HAVE_FCHDIR static void edit_deep_directories(struct archive_write_disk *a) { int ret; char *tail = a->name; a->restore_pwd = -1; /* If path is short, avoid the open() below. */ if (strlen(tail) <= PATH_MAX) return; /* Try to record our starting dir. */ a->restore_pwd = open(".", O_RDONLY | O_BINARY); if (a->restore_pwd < 0) return; /* As long as the path is too long... */ while (strlen(tail) > PATH_MAX) { /* Locate a dir prefix shorter than PATH_MAX. */ tail += PATH_MAX - 8; while (tail > a->name && *tail != '/') tail--; /* Exit if we find a too-long path component. */ if (tail <= a->name) return; /* Create the intermediate dir and chdir to it. */ *tail = '\0'; /* Terminate dir portion */ ret = create_dir(a, a->name); if (ret == ARCHIVE_OK && chdir(a->name) != 0) ret = ARCHIVE_WARN; *tail = '/'; /* Restore the / we removed. */ if (ret != ARCHIVE_OK) return; tail++; /* The chdir() succeeded; we've now shortened the path. */ a->name = tail; } return; } #endif /* * The main restore function. */ static int restore_entry(struct archive_write_disk *a) { int ret = ARCHIVE_OK, en; if (a->flags & ARCHIVE_EXTRACT_UNLINK && !S_ISDIR(a->mode)) { /* * TODO: Fix this. Apparently, there are platforms * that still allow root to hose the entire filesystem * by unlinking a dir. The S_ISDIR() test above * prevents us from using unlink() here if the new * object is a dir, but that doesn't mean the old * object isn't a dir. */ if (unlink(a->name) == 0) { /* We removed it, reset cached stat. */ a->pst = NULL; } else if (errno == ENOENT) { /* File didn't exist, that's just as good. */ } else if (rmdir(a->name) == 0) { /* It was a dir, but now it's gone. */ a->pst = NULL; } else { /* We tried, but couldn't get rid of it. */ archive_set_error(&a->archive, errno, "Could not unlink"); return(ARCHIVE_WARN); } } /* Try creating it first; if this fails, we'll try to recover. */ en = create_filesystem_object(a); if ((en == ENOTDIR || en == ENOENT) && !(a->flags & ARCHIVE_EXTRACT_NO_AUTODIR)) { /* If the parent dir doesn't exist, try creating it. */ create_parent_dir(a, a->name); /* Now try to create the object again. */ en = create_filesystem_object(a); } if ((en == EISDIR || en == EEXIST) && (a->flags & ARCHIVE_EXTRACT_NO_OVERWRITE)) { /* If we're not overwriting, we're done. */ archive_set_error(&a->archive, en, "Already exists"); return (ARCHIVE_WARN); } /* * Some platforms return EISDIR if you call * open(O_WRONLY | O_EXCL | O_CREAT) on a directory, some * return EEXIST. POSIX is ambiguous, requiring EISDIR * for open(O_WRONLY) on a dir and EEXIST for open(O_EXCL | O_CREAT) * on an existing item. */ if (en == EISDIR) { /* A dir is in the way of a non-dir, rmdir it. */ if (rmdir(a->name) != 0) { archive_set_error(&a->archive, errno, "Can't remove already-existing dir"); return (ARCHIVE_WARN); } a->pst = NULL; /* Try again. */ en = create_filesystem_object(a); } else if (en == EEXIST) { /* * We know something is in the way, but we don't know what; * we need to find out before we go any further. */ int r = 0; /* * The SECURE_SYMLINK logic has already removed a * symlink to a dir if the client wants that. So * follow the symlink if we're creating a dir. */ if (S_ISDIR(a->mode)) r = stat(a->name, &a->st); /* * If it's not a dir (or it's a broken symlink), * then don't follow it. */ if (r != 0 || !S_ISDIR(a->mode)) r = lstat(a->name, &a->st); if (r != 0) { archive_set_error(&a->archive, errno, "Can't stat existing object"); return (ARCHIVE_WARN); } /* * NO_OVERWRITE_NEWER doesn't apply to directories. */ if ((a->flags & ARCHIVE_EXTRACT_NO_OVERWRITE_NEWER) && !S_ISDIR(a->st.st_mode)) { if (!older(&(a->st), a->entry)) { archive_set_error(&a->archive, 0, "File on disk is not older; skipping."); return (ARCHIVE_FAILED); } } /* If it's our archive, we're done. */ if (a->skip_file_dev > 0 && a->skip_file_ino > 0 && a->st.st_dev == a->skip_file_dev && a->st.st_ino == a->skip_file_ino) { archive_set_error(&a->archive, 0, "Refusing to overwrite archive"); return (ARCHIVE_FAILED); } if (!S_ISDIR(a->st.st_mode)) { /* A non-dir is in the way, unlink it. */ if (unlink(a->name) != 0) { archive_set_error(&a->archive, errno, "Can't unlink already-existing object"); return (ARCHIVE_WARN); } a->pst = NULL; /* Try again. */ en = create_filesystem_object(a); } else if (!S_ISDIR(a->mode)) { /* A dir is in the way of a non-dir, rmdir it. */ if (rmdir(a->name) != 0) { archive_set_error(&a->archive, errno, "Can't remove already-existing dir"); return (ARCHIVE_WARN); } /* Try again. */ en = create_filesystem_object(a); } else { /* * There's a dir in the way of a dir. Don't * waste time with rmdir()/mkdir(), just fix * up the permissions on the existing dir. * Note that we don't change perms on existing * dirs unless _EXTRACT_PERM is specified. */ if ((a->mode != a->st.st_mode) && (a->todo & TODO_MODE_FORCE)) a->deferred |= (a->todo & TODO_MODE); /* Ownership doesn't need deferred fixup. */ en = 0; /* Forget the EEXIST. */ } } if (en) { /* Everything failed; give up here. */ archive_set_error(&a->archive, en, "Can't create '%s'", a->name); return (ARCHIVE_WARN); } a->pst = NULL; /* Cached stat data no longer valid. */ return (ret); } /* * Returns 0 if creation succeeds, or else returns errno value from * the failed system call. Note: This function should only ever perform * a single system call. */ int create_filesystem_object(struct archive_write_disk *a) { /* Create the entry. */ const char *linkname; mode_t final_mode, mode; int r; /* We identify hard/symlinks according to the link names. */ /* Since link(2) and symlink(2) don't handle modes, we're done here. */ linkname = archive_entry_hardlink(a->entry); if (linkname != NULL) { r = link(linkname, a->name) ? errno : 0; /* * New cpio and pax formats allow hardlink entries * to carry data, so we may have to open the file * for hardlink entries. * * If the hardlink was successfully created and * the archive doesn't have carry data for it, * consider it to be non-authoritive for meta data. * This is consistent with GNU tar and BSD pax. * If the hardlink does carry data, let the last * archive entry decide ownership. */ if (r == 0 && a->filesize <= 0) { a->todo = 0; a->deferred = 0; } if (r == 0 && a->filesize > 0) { a->fd = open(a->name, O_WRONLY | O_TRUNC | O_BINARY); if (a->fd < 0) r = errno; } return (r); } linkname = archive_entry_symlink(a->entry); if (linkname != NULL) return symlink(linkname, a->name) ? errno : 0; /* * The remaining system calls all set permissions, so let's * try to take advantage of that to avoid an extra chmod() * call. (Recall that umask is set to zero right now!) */ /* Mode we want for the final restored object (w/o file type bits). */ final_mode = a->mode & 07777; /* * The mode that will actually be restored in this step. Note * that SUID, SGID, etc, require additional work to ensure * security, so we never restore them at this point. */ mode = final_mode & 0777; switch (a->mode & AE_IFMT) { default: /* POSIX requires that we fall through here. */ /* FALLTHROUGH */ case AE_IFREG: a->fd = open(a->name, O_WRONLY | O_CREAT | O_EXCL | O_BINARY, mode); r = (a->fd < 0); break; case AE_IFCHR: #ifdef HAVE_MKNOD /* Note: we use AE_IFCHR for the case label, and * S_IFCHR for the mknod() call. This is correct. */ r = mknod(a->name, mode | S_IFCHR, archive_entry_rdev(a->entry)); #else /* TODO: Find a better way to warn about our inability * to restore a char device node. */ return (EINVAL); #endif /* HAVE_MKNOD */ break; case AE_IFBLK: #ifdef HAVE_MKNOD r = mknod(a->name, mode | S_IFBLK, archive_entry_rdev(a->entry)); #else /* TODO: Find a better way to warn about our inability * to restore a block device node. */ return (EINVAL); #endif /* HAVE_MKNOD */ break; case AE_IFDIR: mode = (mode | MINIMUM_DIR_MODE) & MAXIMUM_DIR_MODE; r = mkdir(a->name, mode); if (r == 0) { /* Defer setting dir times. */ a->deferred |= (a->todo & TODO_TIMES); a->todo &= ~TODO_TIMES; /* Never use an immediate chmod(). */ /* We can't avoid the chmod() entirely if EXTRACT_PERM * because of SysV SGID inheritance. */ if ((mode != final_mode) || (a->flags & ARCHIVE_EXTRACT_PERM)) a->deferred |= (a->todo & TODO_MODE); a->todo &= ~TODO_MODE; } break; case AE_IFIFO: #ifdef HAVE_MKFIFO r = mkfifo(a->name, mode); #else /* TODO: Find a better way to warn about our inability * to restore a fifo. */ return (EINVAL); #endif /* HAVE_MKFIFO */ break; } /* All the system calls above set errno on failure. */ if (r) return (errno); /* If we managed to set the final mode, we've avoided a chmod(). */ if (mode == final_mode) a->todo &= ~TODO_MODE; return (0); } /* * Cleanup function for archive_extract. Mostly, this involves processing * the fixup list, which is used to address a number of problems: * * Dir permissions might prevent us from restoring a file in that * dir, so we restore the dir with minimum 0700 permissions first, * then correct the mode at the end. * * Similarly, the act of restoring a file touches the directory * and changes the timestamp on the dir, so we have to touch-up dir * timestamps at the end as well. * * Some file flags can interfere with the restore by, for example, * preventing the creation of hardlinks to those files. * * Note that tar/cpio do not require that archives be in a particular * order; there is no way to know when the last file has been restored * within a directory, so there's no way to optimize the memory usage * here by fixing up the directory any earlier than the * end-of-archive. * * XXX TODO: Directory ACLs should be restored here, for the same * reason we set directory perms here. XXX */ static int _archive_write_close(struct archive *_a) { struct archive_write_disk *a = (struct archive_write_disk *)_a; struct fixup_entry *next, *p; int ret; __archive_check_magic(&a->archive, ARCHIVE_WRITE_DISK_MAGIC, ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA, "archive_write_disk_close"); ret = _archive_write_finish_entry(&a->archive); /* Sort dir list so directories are fixed up in depth-first order. */ p = sort_dir_list(a->fixup_list); while (p != NULL) { a->pst = NULL; /* Mark stat cache as out-of-date. */ if (p->fixup & TODO_TIMES) { #ifdef HAVE_UTIMES /* {f,l,}utimes() are preferred, when available. */ struct timeval times[2]; times[1].tv_sec = p->mtime; times[1].tv_usec = p->mtime_nanos / 1000; times[0].tv_sec = p->atime; times[0].tv_usec = p->atime_nanos / 1000; #ifdef HAVE_LUTIMES lutimes(p->name, times); #else utimes(p->name, times); #endif #else /* utime() is more portable, but less precise. */ struct utimbuf times; times.modtime = p->mtime; times.actime = p->atime; utime(p->name, ×); #endif } if (p->fixup & TODO_MODE_BASE) chmod(p->name, p->mode); if (p->fixup & TODO_FFLAGS) set_fflags_platform(a, -1, p->name, p->mode, p->fflags_set, 0); next = p->next; free(p->name); free(p); p = next; } a->fixup_list = NULL; return (ret); } static int _archive_write_finish(struct archive *_a) { struct archive_write_disk *a = (struct archive_write_disk *)_a; int ret; ret = _archive_write_close(&a->archive); if (a->cleanup_gid != NULL && a->lookup_gid_data != NULL) (a->cleanup_gid)(a->lookup_gid_data); if (a->cleanup_uid != NULL && a->lookup_uid_data != NULL) (a->cleanup_uid)(a->lookup_uid_data); archive_string_free(&a->_name_data); archive_string_free(&a->archive.error_string); archive_string_free(&a->path_safe); free(a); return (ret); } /* * Simple O(n log n) merge sort to order the fixup list. In * particular, we want to restore dir timestamps depth-first. */ static struct fixup_entry * sort_dir_list(struct fixup_entry *p) { struct fixup_entry *a, *b, *t; if (p == NULL) return (NULL); /* A one-item list is already sorted. */ if (p->next == NULL) return (p); /* Step 1: split the list. */ t = p; a = p->next->next; while (a != NULL) { /* Step a twice, t once. */ a = a->next; if (a != NULL) a = a->next; t = t->next; } /* Now, t is at the mid-point, so break the list here. */ b = t->next; t->next = NULL; a = p; /* Step 2: Recursively sort the two sub-lists. */ a = sort_dir_list(a); b = sort_dir_list(b); /* Step 3: Merge the returned lists. */ /* Pick the first element for the merged list. */ if (strcmp(a->name, b->name) > 0) { t = p = a; a = a->next; } else { t = p = b; b = b->next; } /* Always put the later element on the list first. */ while (a != NULL && b != NULL) { if (strcmp(a->name, b->name) > 0) { t->next = a; a = a->next; } else { t->next = b; b = b->next; } t = t->next; } /* Only one list is non-empty, so just splice it on. */ if (a != NULL) t->next = a; if (b != NULL) t->next = b; return (p); } /* * Returns a new, initialized fixup entry. * * TODO: Reduce the memory requirements for this list by using a tree * structure rather than a simple list of names. */ static struct fixup_entry * new_fixup(struct archive_write_disk *a, const char *pathname) { struct fixup_entry *fe; fe = (struct fixup_entry *)malloc(sizeof(struct fixup_entry)); if (fe == NULL) return (NULL); fe->next = a->fixup_list; a->fixup_list = fe; fe->fixup = 0; fe->name = strdup(pathname); return (fe); } /* * Returns a fixup structure for the current entry. */ static struct fixup_entry * current_fixup(struct archive_write_disk *a, const char *pathname) { if (a->current_fixup == NULL) a->current_fixup = new_fixup(a, pathname); return (a->current_fixup); } /* TODO: Make this work. */ /* * TODO: The deep-directory support bypasses this; disable deep directory * support if we're doing symlink checks. */ /* * TODO: Someday, integrate this with the deep dir support; they both * scan the path and both can be optimized by comparing against other * recent paths. */ static int check_symlinks(struct archive_write_disk *a) { char *pn, *p; char c; int r; struct stat st; /* * Guard against symlink tricks. Reject any archive entry whose * destination would be altered by a symlink. */ /* Whatever we checked last time doesn't need to be re-checked. */ pn = a->name; p = a->path_safe.s; while ((*pn != '\0') && (*p == *pn)) ++p, ++pn; c = pn[0]; /* Keep going until we've checked the entire name. */ while (pn[0] != '\0' && (pn[0] != '/' || pn[1] != '\0')) { /* Skip the next path element. */ while (*pn != '\0' && *pn != '/') ++pn; c = pn[0]; pn[0] = '\0'; /* Check that we haven't hit a symlink. */ r = lstat(a->name, &st); if (r != 0) { /* We've hit a dir that doesn't exist; stop now. */ if (errno == ENOENT) break; } else if (S_ISLNK(st.st_mode)) { if (c == '\0') { /* * Last element is symlink; remove it * so we can overwrite it with the * item being extracted. */ if (unlink(a->name)) { archive_set_error(&a->archive, errno, "Could not remove symlink %s", a->name); pn[0] = c; return (ARCHIVE_WARN); } a->pst = NULL; /* * Even if we did remove it, a warning * is in order. The warning is silly, * though, if we're just replacing one * symlink with another symlink. */ if (!S_ISLNK(a->mode)) { archive_set_error(&a->archive, 0, "Removing symlink %s", a->name); } /* Symlink gone. No more problem! */ pn[0] = c; return (0); } else if (a->flags & ARCHIVE_EXTRACT_UNLINK) { /* User asked us to remove problems. */ if (unlink(a->name) != 0) { archive_set_error(&a->archive, 0, "Cannot remove intervening symlink %s", a->name); pn[0] = c; return (ARCHIVE_WARN); } a->pst = NULL; } else { archive_set_error(&a->archive, 0, "Cannot extract through symlink %s", a->name); pn[0] = c; return (ARCHIVE_WARN); } } } pn[0] = c; /* We've checked and/or cleaned the whole path, so remember it. */ archive_strcpy(&a->path_safe, a->name); return (ARCHIVE_OK); } /* * Canonicalize the pathname. In particular, this strips duplicate * '/' characters, '.' elements, and trailing '/'. It also raises an * error for an empty path, a trailing '..' or (if _SECURE_NODOTDOT is * set) any '..' in the path. */ static int cleanup_pathname(struct archive_write_disk *a) { char *dest, *src; char separator = '\0'; dest = src = a->name; if (*src == '\0') { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Invalid empty pathname"); return (ARCHIVE_FAILED); } /* Skip leading '/'. */ if (*src == '/') separator = *src++; /* Scan the pathname one element at a time. */ for (;;) { /* src points to first char after '/' */ if (src[0] == '\0') { break; } else if (src[0] == '/') { /* Found '//', ignore second one. */ src++; continue; } else if (src[0] == '.') { if (src[1] == '\0') { /* Ignore trailing '.' */ break; } else if (src[1] == '/') { /* Skip './'. */ src += 2; continue; } else if (src[1] == '.') { if (src[2] == '/' || src[2] == '\0') { /* Conditionally warn about '..' */ if (a->flags & ARCHIVE_EXTRACT_SECURE_NODOTDOT) { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Path contains '..'"); return (ARCHIVE_FAILED); } } /* * Note: Under no circumstances do we * remove '..' elements. In * particular, restoring * '/foo/../bar/' should create the * 'foo' dir as a side-effect. */ } } /* Copy current element, including leading '/'. */ if (separator) *dest++ = '/'; while (*src != '\0' && *src != '/') { *dest++ = *src++; } if (*src == '\0') break; /* Skip '/' separator. */ separator = *src++; } /* * We've just copied zero or more path elements, not including the * final '/'. */ if (dest == a->name) { /* * Nothing got copied. The path must have been something * like '.' or '/' or './' or '/././././/./'. */ if (separator) *dest++ = '/'; else *dest++ = '.'; } /* Terminate the result. */ *dest = '\0'; return (ARCHIVE_OK); } /* * Create the parent directory of the specified path, assuming path * is already in mutable storage. */ static int create_parent_dir(struct archive_write_disk *a, char *path) { char *slash; int r; /* Remove tail element to obtain parent name. */ slash = strrchr(path, '/'); if (slash == NULL) return (ARCHIVE_OK); *slash = '\0'; r = create_dir(a, path); *slash = '/'; return (r); } /* * Create the specified dir, recursing to create parents as necessary. * * Returns ARCHIVE_OK if the path exists when we're done here. * Otherwise, returns ARCHIVE_WARN. * Assumes path is in mutable storage; path is unchanged on exit. */ static int create_dir(struct archive_write_disk *a, char *path) { struct stat st; struct fixup_entry *le; char *slash, *base; mode_t mode_final, mode; int r; r = ARCHIVE_OK; /* Check for special names and just skip them. */ slash = strrchr(path, '/'); if (slash == NULL) base = path; else base = slash + 1; if (base[0] == '\0' || (base[0] == '.' && base[1] == '\0') || (base[0] == '.' && base[1] == '.' && base[2] == '\0')) { /* Don't bother trying to create null path, '.', or '..'. */ if (slash != NULL) { *slash = '\0'; r = create_dir(a, path); *slash = '/'; return (r); } return (ARCHIVE_OK); } /* * Yes, this should be stat() and not lstat(). Using lstat() * here loses the ability to extract through symlinks. Also note * that this should not use the a->st cache. */ if (stat(path, &st) == 0) { if (S_ISDIR(st.st_mode)) return (ARCHIVE_OK); if ((a->flags & ARCHIVE_EXTRACT_NO_OVERWRITE)) { archive_set_error(&a->archive, EEXIST, "Can't create directory '%s'", path); return (ARCHIVE_WARN); } if (unlink(path) != 0) { archive_set_error(&a->archive, errno, "Can't create directory '%s': " "Conflicting file cannot be removed"); return (ARCHIVE_WARN); } } else if (errno != ENOENT && errno != ENOTDIR) { /* Stat failed? */ archive_set_error(&a->archive, errno, "Can't test directory '%s'", path); return (ARCHIVE_WARN); } else if (slash != NULL) { *slash = '\0'; r = create_dir(a, path); *slash = '/'; if (r != ARCHIVE_OK) return (r); } /* * Mode we want for the final restored directory. Per POSIX, * implicitly-created dirs must be created obeying the umask. * There's no mention whether this is different for privileged * restores (which the rest of this code handles by pretending * umask=0). I've chosen here to always obey the user's umask for * implicit dirs, even if _EXTRACT_PERM was specified. */ mode_final = DEFAULT_DIR_MODE & ~a->user_umask; /* Mode we want on disk during the restore process. */ mode = mode_final; mode |= MINIMUM_DIR_MODE; mode &= MAXIMUM_DIR_MODE; if (mkdir(path, mode) == 0) { if (mode != mode_final) { le = new_fixup(a, path); le->fixup |=TODO_MODE_BASE; le->mode = mode_final; } return (ARCHIVE_OK); } /* * Without the following check, a/b/../b/c/d fails at the * second visit to 'b', so 'd' can't be created. Note that we * don't add it to the fixup list here, as it's already been * added. */ if (stat(path, &st) == 0 && S_ISDIR(st.st_mode)) return (ARCHIVE_OK); archive_set_error(&a->archive, errno, "Failed to create dir '%s'", path); return (ARCHIVE_WARN); } /* * Note: Although we can skip setting the user id if the desired user * id matches the current user, we cannot skip setting the group, as * many systems set the gid based on the containing directory. So * we have to perform a chown syscall if we want to set the SGID * bit. (The alternative is to stat() and then possibly chown(); it's * more efficient to skip the stat() and just always chown().) Note * that a successful chown() here clears the TODO_SGID_CHECK bit, which * allows set_mode to skip the stat() check for the GID. */ static int set_ownership(struct archive_write_disk *a) { /* If we know we can't change it, don't bother trying. */ if (a->user_uid != 0 && a->user_uid != a->uid) { archive_set_error(&a->archive, errno, "Can't set UID=%d", a->uid); return (ARCHIVE_WARN); } #ifdef HAVE_FCHOWN /* If we have an fd, we can avoid a race. */ if (a->fd >= 0 && fchown(a->fd, a->uid, a->gid) == 0) { /* We've set owner and know uid/gid are correct. */ a->todo &= ~(TODO_OWNER | TODO_SGID_CHECK | TODO_SUID_CHECK); return (ARCHIVE_OK); } #endif /* We prefer lchown() but will use chown() if that's all we have. */ /* Of course, if we have neither, this will always fail. */ #ifdef HAVE_LCHOWN if (lchown(a->name, a->uid, a->gid) == 0) { /* We've set owner and know uid/gid are correct. */ a->todo &= ~(TODO_OWNER | TODO_SGID_CHECK | TODO_SUID_CHECK); return (ARCHIVE_OK); } #elif HAVE_CHOWN if (!S_ISLNK(a->mode) && chown(a->name, a->uid, a->gid) == 0) { /* We've set owner and know uid/gid are correct. */ a->todo &= ~(TODO_OWNER | TODO_SGID_CHECK | TODO_SUID_CHECK); return (ARCHIVE_OK); } #endif archive_set_error(&a->archive, errno, "Can't set user=%d/group=%d for %s", a->uid, a->gid, a->name); return (ARCHIVE_WARN); } #ifdef HAVE_UTIMES /* * The utimes()-family functions provide high resolution and * a way to set time on an fd or a symlink. We prefer them * when they're available. */ static int set_time(struct archive_write_disk *a) { struct timeval times[2]; /* If no time was provided, we're done. */ if (!archive_entry_atime_is_set(a->entry) && !archive_entry_mtime_is_set(a->entry)) return (ARCHIVE_OK); /* We know at least one is set, so... */ if (archive_entry_mtime_is_set(a->entry)) { times[1].tv_sec = archive_entry_mtime(a->entry); times[1].tv_usec = archive_entry_mtime_nsec(a->entry) / 1000; } else { times[1].tv_sec = a->start_time; times[1].tv_usec = 0; } /* If no atime was specified, use start time instead. */ /* In theory, it would be marginally more correct to use * time(NULL) here, but that would cost us an extra syscall * for little gain. */ if (archive_entry_atime_is_set(a->entry)) { times[0].tv_sec = archive_entry_atime(a->entry); times[0].tv_usec = archive_entry_atime_nsec(a->entry) / 1000; } else { times[0].tv_sec = a->start_time; times[0].tv_usec = 0; } #ifdef HAVE_FUTIMES if (a->fd >= 0 && futimes(a->fd, times) == 0) { return (ARCHIVE_OK); } #endif #ifdef HAVE_LUTIMES if (lutimes(a->name, times) != 0) #else if (!S_ISLNK(a->mode) && utimes(a->name, times) != 0) #endif { archive_set_error(&a->archive, errno, "Can't update time for %s", a->name); return (ARCHIVE_WARN); } /* * Note: POSIX does not provide a portable way to restore ctime. * (Apart from resetting the system clock, which is distasteful.) * So, any restoration of ctime will necessarily be OS-specific. */ /* XXX TODO: Can FreeBSD restore ctime? XXX */ return (ARCHIVE_OK); } #elif defined(HAVE_UTIME) /* * utime() is an older, more standard interface that we'll use * if utimes() isn't available. */ static int set_time(struct archive_write_disk *a) { struct utimbuf times; /* If no time was provided, we're done. */ if (!archive_entry_atime_is_set(a->entry) && !archive_entry_mtime_is_set(a->entry)) return (ARCHIVE_OK); /* We know at least one is set, so... */ /* Set mtime from mtime if set, else start time. */ if (archive_entry_mtime_is_set(a->entry)) times.modtime = archive_entry_mtime(a->entry); else times.modtime = a->start_time; /* Set atime from provided atime, else mtime. */ if (archive_entry_atime_is_set(a->entry)) times.actime = archive_entry_atime(a->entry); else times.actime = a->start_time; if (!S_ISLNK(a->mode) && utime(a->name, ×) != 0) { archive_set_error(&a->archive, errno, "Can't update time for %s", a->name); return (ARCHIVE_WARN); } return (ARCHIVE_OK); } #else /* This platform doesn't give us a way to restore the time. */ static int set_time(struct archive_write_disk *a) { (void)a; /* UNUSED */ archive_set_error(&a->archive, errno, "Can't update time for %s", a->name); return (ARCHIVE_WARN); } #endif static int set_mode(struct archive_write_disk *a, int mode) { int r = ARCHIVE_OK; mode &= 07777; /* Strip off file type bits. */ if (a->todo & TODO_SGID_CHECK) { /* * If we don't know the GID is right, we must stat() * to verify it. We can't just check the GID of this * process, since systems sometimes set GID from * the enclosing dir or based on ACLs. */ if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK) return (r); if (a->pst->st_gid != a->gid) { mode &= ~ S_ISGID; if (a->flags & ARCHIVE_EXTRACT_OWNER) { /* * This is only an error if you * requested owner restore. If you * didn't, we'll try to restore * sgid/suid, but won't consider it a * problem if we can't. */ archive_set_error(&a->archive, -1, "Can't restore SGID bit"); r = ARCHIVE_WARN; } } /* While we're here, double-check the UID. */ if (a->pst->st_uid != a->uid && (a->todo & TODO_SUID)) { mode &= ~ S_ISUID; if (a->flags & ARCHIVE_EXTRACT_OWNER) { archive_set_error(&a->archive, -1, "Can't restore SUID bit"); r = ARCHIVE_WARN; } } a->todo &= ~TODO_SGID_CHECK; a->todo &= ~TODO_SUID_CHECK; } else if (a->todo & TODO_SUID_CHECK) { /* * If we don't know the UID is right, we can just check * the user, since all systems set the file UID from * the process UID. */ if (a->user_uid != a->uid) { mode &= ~ S_ISUID; if (a->flags & ARCHIVE_EXTRACT_OWNER) { archive_set_error(&a->archive, -1, "Can't make file SUID"); r = ARCHIVE_WARN; } } a->todo &= ~TODO_SUID_CHECK; } if (S_ISLNK(a->mode)) { #ifdef HAVE_LCHMOD /* * If this is a symlink, use lchmod(). If the * platform doesn't support lchmod(), just skip it. A * platform that doesn't provide a way to set * permissions on symlinks probably ignores * permissions on symlinks, so a failure here has no * impact. */ if (lchmod(a->name, mode) != 0) { archive_set_error(&a->archive, errno, "Can't set permissions to 0%o", (int)mode); r = ARCHIVE_WARN; } #endif } else if (!S_ISDIR(a->mode)) { /* * If it's not a symlink and not a dir, then use * fchmod() or chmod(), depending on whether we have * an fd. Dirs get their perms set during the * post-extract fixup, which is handled elsewhere. */ #ifdef HAVE_FCHMOD if (a->fd >= 0) { if (fchmod(a->fd, mode) != 0) { archive_set_error(&a->archive, errno, "Can't set permissions to 0%o", (int)mode); r = ARCHIVE_WARN; } } else #endif /* If this platform lacks fchmod(), then * we'll just use chmod(). */ if (chmod(a->name, mode) != 0) { archive_set_error(&a->archive, errno, "Can't set permissions to 0%o", (int)mode); r = ARCHIVE_WARN; } } return (r); } static int set_fflags(struct archive_write_disk *a) { struct fixup_entry *le; unsigned long set, clear; int r; int critical_flags; mode_t mode = archive_entry_mode(a->entry); /* * Make 'critical_flags' hold all file flags that can't be * immediately restored. For example, on BSD systems, * SF_IMMUTABLE prevents hardlinks from being created, so * should not be set until after any hardlinks are created. To * preserve some semblance of portability, this uses #ifdef * extensively. Ugly, but it works. * * Yes, Virginia, this does create a security race. It's mitigated * somewhat by the practice of creating dirs 0700 until the extract * is done, but it would be nice if we could do more than that. * People restoring critical file systems should be wary of * other programs that might try to muck with files as they're * being restored. */ /* Hopefully, the compiler will optimize this mess into a constant. */ critical_flags = 0; #ifdef SF_IMMUTABLE critical_flags |= SF_IMMUTABLE; #endif #ifdef UF_IMMUTABLE critical_flags |= UF_IMMUTABLE; #endif #ifdef SF_APPEND critical_flags |= SF_APPEND; #endif #ifdef UF_APPEND critical_flags |= UF_APPEND; #endif #ifdef EXT2_APPEND_FL critical_flags |= EXT2_APPEND_FL; #endif #ifdef EXT2_IMMUTABLE_FL critical_flags |= EXT2_IMMUTABLE_FL; #endif if (a->todo & TODO_FFLAGS) { archive_entry_fflags(a->entry, &set, &clear); /* * The first test encourages the compiler to eliminate * all of this if it's not necessary. */ if ((critical_flags != 0) && (set & critical_flags)) { le = current_fixup(a, a->name); le->fixup |= TODO_FFLAGS; le->fflags_set = set; /* Store the mode if it's not already there. */ if ((le->fixup & TODO_MODE) == 0) le->mode = mode; } else { r = set_fflags_platform(a, a->fd, a->name, mode, set, clear); if (r != ARCHIVE_OK) return (r); } } return (ARCHIVE_OK); } #if ( defined(HAVE_LCHFLAGS) || defined(HAVE_CHFLAGS) || defined(HAVE_FCHFLAGS) ) && !defined(__linux) static int set_fflags_platform(struct archive_write_disk *a, int fd, const char *name, mode_t mode, unsigned long set, unsigned long clear) { int r; (void)mode; /* UNUSED */ if (set == 0 && clear == 0) return (ARCHIVE_OK); /* * XXX Is the stat here really necessary? Or can I just use * the 'set' flags directly? In particular, I'm not sure * about the correct approach if we're overwriting an existing * file that already has flags on it. XXX */ if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK) return (r); a->st.st_flags &= ~clear; a->st.st_flags |= set; #ifdef HAVE_FCHFLAGS /* If platform has fchflags() and we were given an fd, use it. */ if (fd >= 0 && fchflags(fd, a->st.st_flags) == 0) return (ARCHIVE_OK); #endif /* * If we can't use the fd to set the flags, we'll use the * pathname to set flags. We prefer lchflags() but will use * chflags() if we must. */ #ifdef HAVE_LCHFLAGS if (lchflags(name, a->st.st_flags) == 0) return (ARCHIVE_OK); #elif defined(HAVE_CHFLAGS) if (S_ISLNK(a->st.st_mode)) { archive_set_error(&a->archive, errno, "Can't set file flags on symlink."); return (ARCHIVE_WARN); } if (chflags(name, a->st.st_flags) == 0) return (ARCHIVE_OK); #endif archive_set_error(&a->archive, errno, "Failed to set file flags"); return (ARCHIVE_WARN); } #elif defined(__linux) && defined(EXT2_IOC_GETFLAGS) && defined(EXT2_IOC_SETFLAGS) /* * Linux has flags too, but uses ioctl() to access them instead of * having a separate chflags() system call. */ static int set_fflags_platform(struct archive_write_disk *a, int fd, const char *name, mode_t mode, unsigned long set, unsigned long clear) { int ret; int myfd = fd; unsigned long newflags, oldflags; unsigned long sf_mask = 0; if (set == 0 && clear == 0) return (ARCHIVE_OK); /* Only regular files and dirs can have flags. */ if (!S_ISREG(mode) && !S_ISDIR(mode)) return (ARCHIVE_OK); /* If we weren't given an fd, open it ourselves. */ if (myfd < 0) myfd = open(name, O_RDONLY | O_NONBLOCK | O_BINARY); if (myfd < 0) return (ARCHIVE_OK); /* * Linux has no define for the flags that are only settable by * the root user. This code may seem a little complex, but * there seem to be some Linux systems that lack these * defines. (?) The code below degrades reasonably gracefully * if sf_mask is incomplete. */ #ifdef EXT2_IMMUTABLE_FL sf_mask |= EXT2_IMMUTABLE_FL; #endif #ifdef EXT2_APPEND_FL sf_mask |= EXT2_APPEND_FL; #endif /* * XXX As above, this would be way simpler if we didn't have * to read the current flags from disk. XXX */ ret = ARCHIVE_OK; /* Try setting the flags as given. */ if (ioctl(myfd, EXT2_IOC_GETFLAGS, &oldflags) >= 0) { newflags = (oldflags & ~clear) | set; if (ioctl(myfd, EXT2_IOC_SETFLAGS, &newflags) >= 0) goto cleanup; if (errno != EPERM) goto fail; } /* If we couldn't set all the flags, try again with a subset. */ if (ioctl(myfd, EXT2_IOC_GETFLAGS, &oldflags) >= 0) { newflags &= ~sf_mask; oldflags &= sf_mask; newflags |= oldflags; if (ioctl(myfd, EXT2_IOC_SETFLAGS, &newflags) >= 0) goto cleanup; } /* We couldn't set the flags, so report the failure. */ fail: archive_set_error(&a->archive, errno, "Failed to set file flags"); ret = ARCHIVE_WARN; cleanup: if (fd < 0) close(myfd); return (ret); } #else /* Not HAVE_CHFLAGS && Not __linux */ /* * Of course, some systems have neither BSD chflags() nor Linux' flags * support through ioctl(). */ static int set_fflags_platform(struct archive_write_disk *a, int fd, const char *name, mode_t mode, unsigned long set, unsigned long clear) { (void)a; /* UNUSED */ (void)fd; /* UNUSED */ (void)name; /* UNUSED */ (void)mode; /* UNUSED */ (void)set; /* UNUSED */ (void)clear; /* UNUSED */ return (ARCHIVE_OK); } #endif /* __linux */ #ifndef HAVE_POSIX_ACL /* Default empty function body to satisfy mainline code. */ static int set_acls(struct archive_write_disk *a) { (void)a; /* UNUSED */ return (ARCHIVE_OK); } #else /* * XXX TODO: What about ACL types other than ACCESS and DEFAULT? */ static int set_acls(struct archive_write_disk *a) { int ret; ret = set_acl(a, a->fd, a->entry, ACL_TYPE_ACCESS, ARCHIVE_ENTRY_ACL_TYPE_ACCESS, "access"); if (ret != ARCHIVE_OK) return (ret); ret = set_acl(a, a->fd, a->entry, ACL_TYPE_DEFAULT, ARCHIVE_ENTRY_ACL_TYPE_DEFAULT, "default"); return (ret); } static int set_acl(struct archive_write_disk *a, int fd, struct archive_entry *entry, acl_type_t acl_type, int ae_requested_type, const char *tname) { acl_t acl; acl_entry_t acl_entry; acl_permset_t acl_permset; int ret; int ae_type, ae_permset, ae_tag, ae_id; uid_t ae_uid; gid_t ae_gid; const char *ae_name; int entries; const char *name; ret = ARCHIVE_OK; entries = archive_entry_acl_reset(entry, ae_requested_type); if (entries == 0) return (ARCHIVE_OK); acl = acl_init(entries); while (archive_entry_acl_next(entry, ae_requested_type, &ae_type, &ae_permset, &ae_tag, &ae_id, &ae_name) == ARCHIVE_OK) { acl_create_entry(&acl, &acl_entry); switch (ae_tag) { case ARCHIVE_ENTRY_ACL_USER: acl_set_tag_type(acl_entry, ACL_USER); ae_uid = a->lookup_uid(a->lookup_uid_data, ae_name, ae_id); acl_set_qualifier(acl_entry, &ae_uid); break; case ARCHIVE_ENTRY_ACL_GROUP: acl_set_tag_type(acl_entry, ACL_GROUP); ae_gid = a->lookup_gid(a->lookup_gid_data, ae_name, ae_id); acl_set_qualifier(acl_entry, &ae_gid); break; case ARCHIVE_ENTRY_ACL_USER_OBJ: acl_set_tag_type(acl_entry, ACL_USER_OBJ); break; case ARCHIVE_ENTRY_ACL_GROUP_OBJ: acl_set_tag_type(acl_entry, ACL_GROUP_OBJ); break; case ARCHIVE_ENTRY_ACL_MASK: acl_set_tag_type(acl_entry, ACL_MASK); break; case ARCHIVE_ENTRY_ACL_OTHER: acl_set_tag_type(acl_entry, ACL_OTHER); break; default: /* XXX */ break; } acl_get_permset(acl_entry, &acl_permset); acl_clear_perms(acl_permset); if (ae_permset & ARCHIVE_ENTRY_ACL_EXECUTE) acl_add_perm(acl_permset, ACL_EXECUTE); if (ae_permset & ARCHIVE_ENTRY_ACL_WRITE) acl_add_perm(acl_permset, ACL_WRITE); if (ae_permset & ARCHIVE_ENTRY_ACL_READ) acl_add_perm(acl_permset, ACL_READ); } name = archive_entry_pathname(entry); /* Try restoring the ACL through 'fd' if we can. */ #if HAVE_ACL_SET_FD if (fd >= 0 && acl_type == ACL_TYPE_ACCESS && acl_set_fd(fd, acl) == 0) ret = ARCHIVE_OK; else #else #if HAVE_ACL_SET_FD_NP if (fd >= 0 && acl_set_fd_np(fd, acl, acl_type) == 0) ret = ARCHIVE_OK; else #endif #endif if (acl_set_file(name, acl_type, acl) != 0) { archive_set_error(&a->archive, errno, "Failed to set %s acl", tname); ret = ARCHIVE_WARN; } acl_free(acl); return (ret); } #endif #if HAVE_LSETXATTR /* * Restore extended attributes - Linux implementation */ static int set_xattrs(struct archive_write_disk *a) { struct archive_entry *entry = a->entry; static int warning_done = 0; int ret = ARCHIVE_OK; int i = archive_entry_xattr_reset(entry); while (i--) { const char *name; const void *value; size_t size; archive_entry_xattr_next(entry, &name, &value, &size); if (name != NULL && strncmp(name, "xfsroot.", 8) != 0 && strncmp(name, "system.", 7) != 0) { int e; #if HAVE_FSETXATTR if (a->fd >= 0) e = fsetxattr(a->fd, name, value, size, 0); else #endif { e = lsetxattr(archive_entry_pathname(entry), name, value, size, 0); } if (e == -1) { if (errno == ENOTSUP) { if (!warning_done) { warning_done = 1; archive_set_error(&a->archive, errno, "Cannot restore extended " "attributes on this file " "system"); } } else archive_set_error(&a->archive, errno, "Failed to set extended attribute"); ret = ARCHIVE_WARN; } } else { archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT, "Invalid extended attribute encountered"); ret = ARCHIVE_WARN; } } return (ret); } #else /* * Restore extended attributes - stub implementation for unsupported systems */ static int set_xattrs(struct archive_write_disk *a) { static int warning_done = 0; /* If there aren't any extended attributes, then it's okay not * to extract them, otherwise, issue a single warning. */ if (archive_entry_xattr_count(a->entry) != 0 && !warning_done) { warning_done = 1; archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT, "Cannot restore extended attributes on this system"); return (ARCHIVE_WARN); } /* Warning was already emitted; suppress further warnings. */ return (ARCHIVE_OK); } #endif /* * Trivial implementations of gid/uid lookup functions. * These are normally overridden by the client, but these stub * versions ensure that we always have something that works. */ static gid_t trivial_lookup_gid(void *private_data, const char *gname, gid_t gid) { (void)private_data; /* UNUSED */ (void)gname; /* UNUSED */ return (gid); } static uid_t trivial_lookup_uid(void *private_data, const char *uname, uid_t uid) { (void)private_data; /* UNUSED */ (void)uname; /* UNUSED */ return (uid); } /* * Test if file on disk is older than entry. */ static int older(struct stat *st, struct archive_entry *entry) { /* First, test the seconds and return if we have a definite answer. */ /* Definitely older. */ if (st->st_mtime < archive_entry_mtime(entry)) return (1); /* Definitely younger. */ if (st->st_mtime > archive_entry_mtime(entry)) return (0); /* If this platform supports fractional seconds, try those. */ #if HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC /* Definitely older. */ if (st->st_mtimespec.tv_nsec < archive_entry_mtime_nsec(entry)) return (1); /* Definitely younger. */ if (st->st_mtimespec.tv_nsec > archive_entry_mtime_nsec(entry)) return (0); #elif HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC /* Definitely older. */ if (st->st_mtim.tv_nsec < archive_entry_mtime_nsec(entry)) return (1); /* Definitely older. */ if (st->st_mtim.tv_nsec > archive_entry_mtime_nsec(entry)) return (0); #else /* This system doesn't have high-res timestamps. */ #endif /* Same age, so not older. */ return (0); }