X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Funix_capture.c;h=f9fad4a33ce1a1ece10237d9c90d452743019a3e;hp=a61d91f25f61fdc5f2cf6b924f0db2a9e60c37da;hb=HEAD;hpb=3de1ec66f778edda19865482d685bc6f4e17faf7 diff --git a/src/unix_capture.c b/src/unix_capture.c index a61d91f2..70a81c43 100644 --- a/src/unix_capture.c +++ b/src/unix_capture.c @@ -3,7 +3,7 @@ */ /* - * Copyright (C) 2012, 2013, 2014 Eric Biggers + * Copyright (C) 2012-2018 Eric Biggers * * This file is free software; you can redistribute it and/or modify it under * the terms of the GNU Lesser General Public License as published by the Free @@ -16,10 +16,10 @@ * details. * * You should have received a copy of the GNU Lesser General Public License - * along with this file; if not, see http://www.gnu.org/licenses/. + * along with this file; if not, see https://www.gnu.org/licenses/. */ -#ifndef __WIN32__ +#ifndef _WIN32 #ifdef HAVE_CONFIG_H # include "config.h" @@ -28,17 +28,21 @@ #include #include #include -#include /* for PATH_MAX */ #include +#include +#ifdef HAVE_SYS_XATTR_H +# include +#endif #include #include "wimlib/blob_table.h" -#include "wimlib/capture.h" #include "wimlib/dentry.h" #include "wimlib/error.h" #include "wimlib/reparse.h" +#include "wimlib/scan.h" #include "wimlib/timestamp.h" #include "wimlib/unix_data.h" +#include "wimlib/xattr.h" #ifdef HAVE_FDOPENDIR # define my_fdopendir(dirfd_p) fdopendir(*(dirfd_p)) @@ -99,68 +103,249 @@ my_fdopendir(int *dirfd_p) # define AT_SYMLINK_NOFOLLOW 0x100 #endif +#ifdef HAVE_LINUX_XATTR_SUPPORT +/* + * Retrieves the values of the xattrs named by the null-terminated @names of the + * file at @path and serializes the xattr names and values into @entries. If + * successful, returns the number of bytes used in @entries. If unsuccessful, + * returns -1 and sets errno (ERANGE if @entries was too small). + */ +static ssize_t +gather_xattr_entries(const char *path, const char *names, size_t names_size, + void *entries, size_t entries_size) +{ + const char * const names_end = names + names_size; + void * const entries_end = entries + entries_size; + const char *name = names; + struct wim_xattr_entry *entry = entries; + + do { + size_t name_len = strnlen(name, names_end - name); + void *value; + ssize_t value_len; + + if (name_len == 0 || name_len >= names_end - name) { + ERROR("\"%s\": malformed extended attribute names list", + path); + errno = EINVAL; + return -1; + } + + if (name_len > WIM_XATTR_NAME_MAX) { + WARNING("\"%s\": name of extended attribute \"%s\" is too long to store", + path, name); + goto next_name; + } + + /* + * Take care to always call lgetxattr() with a nonzero size, + * since zero size means to return the value length only. + */ + if (entries_end - (void *)entry <= + sizeof(*entry) + name_len + 1) { + errno = ERANGE; + return -1; + } + + entry->name_len = name_len; + entry->flags = 0; + value = mempcpy(entry->name, name, name_len + 1); + + value_len = lgetxattr(path, name, value, entries_end - value); + if (value_len < 0) { + if (errno != ERANGE) { + ERROR_WITH_ERRNO("\"%s\": unable to read extended attribute \"%s\"", + path, name); + } + return -1; + } + if (value_len > WIM_XATTR_SIZE_MAX) { + WARNING("\"%s\": value of extended attribute \"%s\" is too large to store", + path, name); + goto next_name; + } + entry->value_len = cpu_to_le16(value_len); + entry = value + value_len; + next_name: + name += name_len + 1; + } while (name < names_end); + + return (void *)entry - entries; +} + +static int +create_xattr_item(const char *path, struct wim_inode *inode, + const char *names, size_t names_size) +{ + char _entries[1024]; + char *entries = _entries; + size_t entries_avail = ARRAY_LEN(_entries); + ssize_t entries_size; + int ret; + +retry: + /* Serialize the xattrs into @entries */ + entries_size = gather_xattr_entries(path, names, names_size, + entries, entries_avail); + if (entries_size < 0) { + ret = WIMLIB_ERR_STAT; + if (errno != ERANGE) + goto out; + /* Not enough space in @entries. Reallocate it. */ + if (entries != _entries) + FREE(entries); + ret = WIMLIB_ERR_NOMEM; + entries_avail *= 2; + entries = MALLOC(entries_avail); + if (!entries) + goto out; + goto retry; + } + + /* Copy @entries into an xattr item associated with @inode */ + if ((u32)entries_size != entries_size) { + ERROR("\"%s\": too much xattr data!", path); + ret = WIMLIB_ERR_STAT; + goto out; + } + ret = WIMLIB_ERR_NOMEM; + if (!inode_set_xattrs(inode, entries, entries_size)) + goto out; + + ret = 0; +out: + if (entries != _entries) + FREE(entries); + return ret; +} + +/* + * If the file at @path has Linux-style extended attributes, read them into + * memory and add them to @inode as a tagged item. + */ +static noinline_for_stack int +scan_linux_xattrs(const char *path, struct wim_inode *inode) +{ + char _names[256]; + char *names = _names; + ssize_t names_size = ARRAY_LEN(_names); + int ret = 0; + +retry: + /* Gather the names of the xattrs of the file at @path */ + names_size = llistxattr(path, names, names_size); + if (names_size == 0) /* No xattrs? */ + goto out; + if (names_size < 0) { + /* xattrs unsupported or disabled? */ + if (errno == ENOTSUP || errno == ENOSYS) + goto out; + if (errno == ERANGE) { + /* + * Not enough space in @names. Ask for how much space + * we need, then try again. + */ + names_size = llistxattr(path, NULL, 0); + if (names_size == 0) + goto out; + if (names_size > 0) { + if (names != _names) + FREE(names); + names = MALLOC(names_size); + if (!names) { + ret = WIMLIB_ERR_NOMEM; + goto out; + } + goto retry; + } + } + /* Some other error occurred. */ + ERROR_WITH_ERRNO("\"%s\": unable to list extended attributes", + path); + ret = WIMLIB_ERR_STAT; + goto out; + } + + /* + * We have a nonempty list of xattr names. Gather the xattr values and + * add them as a tagged item. + */ + ret = create_xattr_item(path, inode, names, names_size); +out: + if (names != _names) + FREE(names); + return ret; +} +#endif /* HAVE_LINUX_XATTR_SUPPORT */ + static int -unix_scan_regular_file(const char *path, u64 size, struct wim_inode *inode, +unix_scan_regular_file(const char *path, u64 blocks, u64 size, + struct wim_inode *inode, struct list_head *unhashed_blobs) { - struct blob_descriptor *blob; + struct blob_descriptor *blob = NULL; struct wim_inode_stream *strm; - inode->i_attributes = FILE_ATTRIBUTE_NORMAL; + /* + * Set FILE_ATTRIBUTE_SPARSE_FILE if the file uses less disk space than + * expected given its size. + */ + if (blocks < DIV_ROUND_UP(size, 512)) + inode->i_attributes = FILE_ATTRIBUTE_SPARSE_FILE; + else + inode->i_attributes = FILE_ATTRIBUTE_NORMAL; if (size) { - char *file_on_disk = STRDUP(path); - if (!file_on_disk) - return WIMLIB_ERR_NOMEM; blob = new_blob_descriptor(); - if (!blob) { - FREE(file_on_disk); - return WIMLIB_ERR_NOMEM; - } - blob->file_on_disk = file_on_disk; - blob->file_inode = inode; + if (unlikely(!blob)) + goto err_nomem; + blob->file_on_disk = STRDUP(path); + if (unlikely(!blob->file_on_disk)) + goto err_nomem; blob->blob_location = BLOB_IN_FILE_ON_DISK; blob->size = size; - } else { - blob = NULL; + blob->file_inode = inode; } strm = inode_add_stream(inode, STREAM_TYPE_DATA, NO_STREAM_NAME, blob); - if (!strm) { - free_blob_descriptor(blob); - return WIMLIB_ERR_NOMEM; - } + if (unlikely(!strm)) + goto err_nomem; + prepare_unhashed_blob(blob, inode, strm->stream_id, unhashed_blobs); return 0; + +err_nomem: + free_blob_descriptor(blob); + return WIMLIB_ERR_NOMEM; } static int unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, - char *path, size_t path_len, int dirfd, const char *relpath, - struct capture_params *params); + struct scan_params *params); static int unix_scan_directory(struct wim_dentry *dir_dentry, - char *full_path, size_t full_path_len, int parent_dirfd, const char *dir_relpath, - struct capture_params *params) + struct scan_params *params) { int dirfd; DIR *dir; int ret; - dirfd = my_openat(full_path, parent_dirfd, dir_relpath, O_RDONLY); + dirfd = my_openat(params->cur_path, parent_dirfd, dir_relpath, O_RDONLY); if (dirfd < 0) { - ERROR_WITH_ERRNO("\"%s\": Can't open directory", full_path); + ERROR_WITH_ERRNO("\"%s\": Can't open directory", + params->cur_path); return WIMLIB_ERR_OPENDIR; } dir_dentry->d_inode->i_attributes = FILE_ATTRIBUTE_DIRECTORY; dir = my_fdopendir(&dirfd); if (!dir) { - ERROR_WITH_ERRNO("\"%s\": Can't open directory", full_path); + ERROR_WITH_ERRNO("\"%s\": Can't open directory", + params->cur_path); close(dirfd); return WIMLIB_ERR_OPENDIR; } @@ -170,6 +355,7 @@ unix_scan_directory(struct wim_dentry *dir_dentry, struct dirent *entry; struct wim_dentry *child; size_t name_len; + size_t orig_path_len; errno = 0; entry = readdir(dir); @@ -177,61 +363,85 @@ unix_scan_directory(struct wim_dentry *dir_dentry, if (errno) { ret = WIMLIB_ERR_READ; ERROR_WITH_ERRNO("\"%s\": Error reading directory", - full_path); + params->cur_path); } break; } - if (entry->d_name[0] == '.' && - (entry->d_name[1] == '\0' || - (entry->d_name[1] == '.' && entry->d_name[2] == '\0'))) + name_len = strlen(entry->d_name); + + if (should_ignore_filename(entry->d_name, name_len)) continue; - full_path[full_path_len] = '/'; - name_len = strlen(entry->d_name); - memcpy(&full_path[full_path_len + 1], entry->d_name, name_len + 1); - ret = unix_build_dentry_tree_recursive(&child, - full_path, - full_path_len + 1 + name_len, - dirfd, - &full_path[full_path_len + 1], - params); - full_path[full_path_len] = '\0'; + ret = WIMLIB_ERR_NOMEM; + if (!pathbuf_append_name(params, entry->d_name, name_len, + &orig_path_len)) + break; + ret = unix_build_dentry_tree_recursive(&child, dirfd, + entry->d_name, params); + pathbuf_truncate(params, orig_path_len); if (ret) break; - if (child) - dentry_add_child(dir_dentry, child); + attach_scanned_tree(dir_dentry, child, params->blob_table); } closedir(dir); return ret; } -/* Given an absolute symbolic link target @dest (UNIX-style, beginning - * with '/'), determine whether it points into the directory specified by - * @ino and @dev. If so, return the target modified to be "absolute" - * relative to this directory. Otherwise, return NULL. */ +/* + * Given an absolute symbolic link target (UNIX-style, beginning with '/'), + * determine whether it points into the directory identified by @ino and @dev. + * If yes, return the suffix of @target which is relative to this directory, but + * retaining leading slashes. If no, return @target. + * + * Here are some examples, assuming that the @ino/@dev directory is "/home/e": + * + * Original target New target + * --------------- ---------- + * /home/e/test /test + * /home/e/test/ /test/ + * //home//e//test// //test// + * /home/e (empty string) + * /home/e/ / + * /usr/lib /usr/lib (external link) + * + * Because of the possibility of other links into the @ino/@dev directory and/or + * multiple path separators, we can't simply do a string comparison; instead we + * need to stat() each ancestor directory. + * + * If the link points directly to the @ino/@dev directory with no trailing + * slashes, then the new target will be an empty string. This is not a valid + * UNIX symlink target, but we store this in the archive anyway since the target + * is intended to be de-relativized when the link is extracted. + */ static char * -unix_fixup_abslink(char *dest, u64 ino, u64 dev) +unix_relativize_link_target(char *target, u64 ino, u64 dev) { - char *p = dest; + char *p = target; do { char save; struct stat stbuf; int ret; - /* Skip non-slashes. */ - while (*p && *p != '/') + /* Skip slashes (guaranteed to be at least one here) */ + do { p++; + } while (*p == '/'); + + /* End of string? */ + if (!*p) + break; - /* Skip slashes. */ - while (*p && *p == '/') + /* Skip non-slashes (guaranteed to be at least one here) */ + do { p++; + } while (*p && *p != '/'); - /* Get inode and device for this prefix. */ + /* Get the inode and device numbers for this prefix. */ save = *p; *p = '\0'; - ret = stat(dest, &stbuf); + ret = stat(target, &stbuf); *p = save; if (ret) { @@ -243,85 +453,74 @@ unix_fixup_abslink(char *dest, u64 ino, u64 dev) if (stbuf.st_ino == ino && stbuf.st_dev == dev) { /* Link points inside directory tree being captured. * Return abbreviated path. */ - *--p = '/'; - while (p > dest && *(p - 1) == '/') - p--; return p; } } while (*p); /* Link does not point inside directory tree being captured. */ - return NULL; + return target; } -static int -unix_scan_symlink(const char *full_path, int dirfd, const char *relpath, - struct wim_inode *inode, struct capture_params *params) +static noinline_for_stack int +unix_scan_symlink(int dirfd, const char *relpath, + struct wim_inode *inode, struct scan_params *params) { - char deref_name_buf[4096]; - ssize_t deref_name_len; - char *dest; + char orig_target[REPARSE_POINT_MAX_SIZE]; + char *target = orig_target; int ret; - inode->i_attributes = FILE_ATTRIBUTE_REPARSE_POINT; - inode->i_reparse_tag = WIM_IO_REPARSE_TAG_SYMLINK; - - /* The idea here is to call readlink() to get the UNIX target of the - * symbolic link, then turn the target into a reparse point data buffer - * that contains a relative or absolute symbolic link. */ - deref_name_len = my_readlinkat(full_path, dirfd, relpath, - deref_name_buf, sizeof(deref_name_buf) - 1); - if (deref_name_len < 0) { + /* Read the UNIX symbolic link target. */ + ret = my_readlinkat(params->cur_path, dirfd, relpath, target, + sizeof(orig_target)); + if (unlikely(ret < 0)) { ERROR_WITH_ERRNO("\"%s\": Can't read target of symbolic link", - full_path); + params->cur_path); return WIMLIB_ERR_READLINK; } - - dest = deref_name_buf; - - dest[deref_name_len] = '\0'; - - if ((params->add_flags & WIMLIB_ADD_FLAG_RPFIX) && - dest[0] == '/') - { - char *fixed_dest; - - /* RPFIX (reparse point fixup) mode: Change target of absolute - * symbolic link to be "absolute" relative to the tree being - * captured. */ - fixed_dest = unix_fixup_abslink(dest, - params->capture_root_ino, - params->capture_root_dev); - params->progress.scan.cur_path = full_path; - params->progress.scan.symlink_target = deref_name_buf; - if (fixed_dest) { - /* Link points inside the tree being captured, so it was - * fixed. */ - inode->i_not_rpfixed = 0; - dest = fixed_dest; - ret = do_capture_progress(params, - WIMLIB_SCAN_DENTRY_FIXED_SYMLINK, - NULL); - } else { - /* Link points outside the tree being captured, so it - * was not fixed. */ - ret = do_capture_progress(params, - WIMLIB_SCAN_DENTRY_NOT_FIXED_SYMLINK, - NULL); + if (unlikely(ret >= sizeof(orig_target))) { + ERROR("\"%s\": target of symbolic link is too long", + params->cur_path); + return WIMLIB_ERR_READLINK; + } + target[ret] = '\0'; + + /* If the link is absolute and reparse point fixups are enabled, then + * change it to be "absolute" relative to the tree being captured. */ + if (target[0] == '/' && (params->add_flags & WIMLIB_ADD_FLAG_RPFIX)) { + int status = WIMLIB_SCAN_DENTRY_NOT_FIXED_SYMLINK; + + params->progress.scan.symlink_target = target; + + target = unix_relativize_link_target(target, + params->capture_root_ino, + params->capture_root_dev); + if (target != orig_target) { + /* Link target was fixed. */ + inode->i_rp_flags &= ~WIM_RP_FLAG_NOT_FIXED; + status = WIMLIB_SCAN_DENTRY_FIXED_SYMLINK; } + ret = do_scan_progress(params, status, NULL); if (ret) return ret; } - ret = wim_inode_set_symlink(inode, dest, params->blob_table); - if (ret) + + /* Translate the UNIX symlink target into a Windows reparse point. */ + ret = wim_inode_set_symlink(inode, target, params->blob_table); + if (unlikely(ret)) { + if (ret == WIMLIB_ERR_INVALID_UTF8_STRING) { + ERROR("\"%s\": target of symbolic link is not valid " + "UTF-8. This is not supported.", + params->cur_path); + } return ret; + } - /* Unfortunately, Windows seems to have the concept of "file" symbolic - * links as being different from "directory" symbolic links... so - * FILE_ATTRIBUTE_DIRECTORY needs to be set on the symbolic link if the - * *target* of the symbolic link is a directory. */ + /* On Windows, a reparse point can be set on both directory and + * non-directory files. Usually, a link that is intended to point to a + * (non-)directory is stored as a reparse point on a (non-)directory + * file. Replicate this behavior by examining the target file. */ struct stat stbuf; - if (my_fstatat(full_path, dirfd, relpath, &stbuf, 0) == 0 && + if (my_fstatat(params->cur_path, dirfd, relpath, &stbuf, 0) == 0 && S_ISDIR(stbuf.st_mode)) inode->i_attributes |= FILE_ATTRIBUTE_DIRECTORY; return 0; @@ -329,9 +528,8 @@ unix_scan_symlink(const char *full_path, int dirfd, const char *relpath, static int unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, - char *full_path, size_t full_path_len, int dirfd, const char *relpath, - struct capture_params *params) + struct scan_params *params) { struct wim_dentry *tree = NULL; struct wim_inode *inode = NULL; @@ -339,10 +537,10 @@ unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, struct stat stbuf; int stat_flags; - ret = try_exclude(full_path, full_path_len, params); - if (ret < 0) /* Excluded? */ + ret = try_exclude(params); + if (unlikely(ret < 0)) /* Excluded? */ goto out_progress; - if (ret > 0) /* Error? */ + if (unlikely(ret > 0)) /* Error? */ goto out; if (params->add_flags & (WIMLIB_ADD_FLAG_DEREFERENCE | @@ -351,10 +549,11 @@ unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, else stat_flags = AT_SYMLINK_NOFOLLOW; - ret = my_fstatat(full_path, dirfd, relpath, &stbuf, stat_flags); + ret = my_fstatat(params->cur_path, dirfd, relpath, &stbuf, stat_flags); if (ret) { - ERROR_WITH_ERRNO("\"%s\": Can't read metadata", full_path); + ERROR_WITH_ERRNO("\"%s\": Can't read metadata", + params->cur_path); ret = WIMLIB_ERR_STAT; goto out; } @@ -368,23 +567,26 @@ unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, WIMLIB_ADD_FLAG_NO_UNSUPPORTED_EXCLUDE) { ERROR("\"%s\": File type is unsupported", - full_path); + params->cur_path); ret = WIMLIB_ERR_UNSUPPORTED_FILE; goto out; } - params->progress.scan.cur_path = full_path; - ret = do_capture_progress(params, - WIMLIB_SCAN_DENTRY_UNSUPPORTED, - NULL); + ret = do_scan_progress(params, + WIMLIB_SCAN_DENTRY_UNSUPPORTED, + NULL); goto out; } } ret = inode_table_new_dentry(params->inode_table, relpath, - stbuf.st_ino, stbuf.st_dev, - S_ISDIR(stbuf.st_mode), &tree); - if (ret) + stbuf.st_ino, stbuf.st_dev, false, &tree); + if (unlikely(ret)) { + if (ret == WIMLIB_ERR_INVALID_UTF8_STRING) { + ERROR("\"%s\": filename is not valid UTF-8. " + "This is not supported.", params->cur_path); + } goto out; + } inode = tree->d_inode; @@ -412,6 +614,11 @@ unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, ret = WIMLIB_ERR_NOMEM; goto out; } +#ifdef HAVE_LINUX_XATTR_SUPPORT + ret = scan_linux_xattrs(params->cur_path, inode); + if (ret) + goto out; +#endif } if (params->add_flags & WIMLIB_ADD_FLAG_ROOT) { @@ -421,30 +628,28 @@ unix_build_dentry_tree_recursive(struct wim_dentry **tree_ret, } if (S_ISREG(stbuf.st_mode)) { - ret = unix_scan_regular_file(full_path, stbuf.st_size, - inode, params->unhashed_blobs); + ret = unix_scan_regular_file(params->cur_path, stbuf.st_blocks, + stbuf.st_size, inode, + params->unhashed_blobs); } else if (S_ISDIR(stbuf.st_mode)) { - ret = unix_scan_directory(tree, full_path, full_path_len, - dirfd, relpath, params); + ret = unix_scan_directory(tree, dirfd, relpath, params); } else if (S_ISLNK(stbuf.st_mode)) { - ret = unix_scan_symlink(full_path, dirfd, relpath, - inode, params); + ret = unix_scan_symlink(dirfd, relpath, inode, params); } if (ret) goto out; out_progress: - params->progress.scan.cur_path = full_path; if (likely(tree)) - ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_OK, inode); + ret = do_scan_progress(params, WIMLIB_SCAN_DENTRY_OK, inode); else - ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_EXCLUDED, NULL); + ret = do_scan_progress(params, WIMLIB_SCAN_DENTRY_EXCLUDED, NULL); out: if (unlikely(ret)) { free_dentry_tree(tree, params->blob_table); tree = NULL; - ret = report_capture_error(params, ret, full_path); + ret = report_scan_error(params, ret); } *tree_ret = tree; return ret; @@ -455,13 +660,12 @@ out: * Builds a tree of WIM dentries from an on-disk directory tree (UNIX * version; no NTFS-specific data is captured). * - * @root_ret: Place to return a pointer to the root of the dentry tree. Only - * modified if successful. Set to NULL if the file or directory was - * excluded from capture. + * @root_ret: Place to return a pointer to the root of the dentry tree. Set + * to NULL if the file or directory was excluded from capture. * * @root_disk_path: The path to the root of the directory tree on disk. * - * @params: See doc for `struct capture_params'. + * @params: See doc for `struct scan_params'. * * @return: 0 on success, nonzero on failure. It is a failure if any of * the files cannot be `stat'ed, or if any of the needed @@ -472,31 +676,16 @@ out: */ int unix_build_dentry_tree(struct wim_dentry **root_ret, - const char *root_disk_path, - struct capture_params *params) + const char *root_disk_path, struct scan_params *params) { - size_t path_len; - size_t path_bufsz; - char *path_buf; int ret; - path_len = strlen(root_disk_path); - path_bufsz = min(32790, PATH_MAX + 1); - - if (path_len >= path_bufsz) - return WIMLIB_ERR_INVALID_PARAM; - - path_buf = MALLOC(path_bufsz); - if (!path_buf) - return WIMLIB_ERR_NOMEM; - memcpy(path_buf, root_disk_path, path_len + 1); - - params->capture_root_nchars = path_len; + ret = pathbuf_init(params, root_disk_path); + if (ret) + return ret; - ret = unix_build_dentry_tree_recursive(root_ret, path_buf, path_len, - AT_FDCWD, path_buf, params); - FREE(path_buf); - return ret; + return unix_build_dentry_tree_recursive(root_ret, AT_FDCWD, + root_disk_path, params); } -#endif /* !__WIN32__ */ +#endif /* !_WIN32 */