X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fwin32_capture.c;h=bc5422e85c7feaeebfcd2989aaea0f93b6fdb802;hp=ace087da33abed497ce67d6942e9e2b73a020440;hb=af141a23c4d1540b8a64759bb68c7cd7ff054e72;hpb=86f59c1b36497f3f67dd962642fe450ac9e2b78b diff --git a/src/win32_capture.c b/src/win32_capture.c index ace087da..bc5422e8 100644 --- a/src/win32_capture.c +++ b/src/win32_capture.c @@ -45,7 +45,6 @@ struct winnt_scan_stats { unsigned long num_get_sd_access_denied; unsigned long num_get_sacl_priv_notheld; - unsigned long num_long_path_warnings; }; static inline const wchar_t * @@ -84,9 +83,7 @@ winnt_openat(HANDLE cur_dir, const wchar_t *path, size_t path_nchars, retry: status = (*func_NtOpenFile)(h_ret, perms, &attr, &iosb, - FILE_SHARE_READ | - FILE_SHARE_WRITE | - FILE_SHARE_DELETE, + FILE_SHARE_VALID_FLAGS, FILE_OPEN_REPARSE_POINT | FILE_OPEN_FOR_BACKUP_INTENT | FILE_SYNCHRONOUS_IO_NONALERT | @@ -454,137 +451,256 @@ out_free_buf: return ret; } -/* Reparse point fixup status code */ +/* Reparse point fixup status code */ enum rp_status { - /* Reparse point corresponded to an absolute symbolic link or junction - * point that pointed outside the directory tree being captured, and - * therefore was excluded. */ - RP_EXCLUDED = 0x0, - - /* Reparse point was not fixed as it was either a relative symbolic - * link, a mount point, or something else we could not understand. */ - RP_NOT_FIXED = 0x1, - - /* Reparse point corresponded to an absolute symbolic link or junction - * point that pointed inside the directory tree being captured, where - * the target was specified by a "full" \??\ prefixed path, and - * therefore was fixed to be relative to the root of the directory tree - * being captured. */ - RP_FIXED_FULLPATH = 0x2, - - /* Same as RP_FIXED_FULLPATH, except the absolute link target did not - * have the \??\ prefix. It may have begun with a drive letter though. - * */ - RP_FIXED_ABSPATH = 0x4, - - /* Either RP_FIXED_FULLPATH or RP_FIXED_ABSPATH. */ - RP_FIXED = RP_FIXED_FULLPATH | RP_FIXED_ABSPATH, + /* Reparse point should be excluded from capture */ + RP_EXCLUDED = -0, + + /* Reparse point will be captured literally (no fixup) */ + RP_NOT_FIXED = -1, + + /* Reparse point will be captured with fixup */ + RP_FIXED = -2, }; -/* Given the "substitute name" target of a Windows reparse point, try doing a - * fixup where we change it to be absolute relative to the root of the directory - * tree being captured. +static bool +file_has_ino_and_dev(HANDLE h, u64 ino, u64 dev) +{ + NTSTATUS status; + IO_STATUS_BLOCK iosb; + FILE_INTERNAL_INFORMATION int_info; + FILE_FS_VOLUME_INFORMATION vol_info; + + status = (*func_NtQueryInformationFile)(h, &iosb, + &int_info, sizeof(int_info), + FileInternalInformation); + if (!NT_SUCCESS(status)) + return false; + + if (int_info.IndexNumber.QuadPart != ino) + return false; + + status = (*func_NtQueryVolumeInformationFile)(h, &iosb, + &vol_info, sizeof(vol_info), + FileFsVolumeInformation); + if (!(NT_SUCCESS(status) || status == STATUS_BUFFER_OVERFLOW)) + return false; + + if (iosb.Information < + offsetof(FILE_FS_VOLUME_INFORMATION, VolumeSerialNumber) + + sizeof(vol_info.VolumeSerialNumber)) + return false; + + return (vol_info.VolumeSerialNumber == dev); +} + +/* + * Given an (expected) NT namespace symbolic link or junction target @target of + * length @target_nbytes, determine if a prefix of the target points to a file + * identified by @capture_root_ino and @capture_root_dev. + * + * If yes, return a pointer to the portion of the link following this prefix. * - * Note that this is only executed when WIMLIB_ADD_FLAG_RPFIX has been - * set. + * If no, return NULL. * - * @capture_root_ino and @capture_root_dev indicate the inode number and device - * of the root of the directory tree being captured. They are meant to identify - * this directory (as an alternative to its actual path, which could potentially - * be reached via multiple destinations due to other symbolic links). This may - * not work properly on FAT, which doesn't seem to supply proper inode numbers - * or file IDs. However, FAT doesn't support reparse points so this function - * wouldn't even be called anyway. + * If the link target does not appear to be a valid NT namespace path, return + * @target itself. */ -static enum rp_status -winnt_capture_maybe_rpfix_target(wchar_t *target, u16 *target_nbytes_p, - u64 capture_root_ino, u64 capture_root_dev, - u32 rptag) +static const wchar_t * +winnt_get_root_relative_target(const wchar_t *target, size_t target_nbytes, + u64 capture_root_ino, u64 capture_root_dev) { - u16 target_nchars = *target_nbytes_p / 2; - size_t stripped_chars; - wchar_t *orig_target; - int ret; + UNICODE_STRING name; + OBJECT_ATTRIBUTES attr; + IO_STATUS_BLOCK iosb; + NTSTATUS status; + const wchar_t *target_end; + const wchar_t *p; - ret = parse_substitute_name(target, *target_nbytes_p, rptag); - if (ret < 0) - return RP_NOT_FIXED; - stripped_chars = ret; - if (stripped_chars) - stripped_chars -= 2; - target[target_nchars] = L'\0'; - orig_target = target; - target = capture_fixup_absolute_symlink(target + stripped_chars, - capture_root_ino, capture_root_dev); - if (!target) - return RP_EXCLUDED; - target_nchars = wcslen(target); - wmemmove(orig_target + stripped_chars, target, target_nchars + 1); - *target_nbytes_p = (target_nchars + stripped_chars) * sizeof(wchar_t); - if (stripped_chars) - return RP_FIXED_FULLPATH; - else - return RP_FIXED_ABSPATH; + target_end = target + (target_nbytes / sizeof(wchar_t)); + + /* Empty path??? */ + if (target_end == target) + return target; + + /* No leading slash??? */ + if (target[0] != L'\\') + return target; + + /* UNC path??? */ + if ((target_end - target) >= 2 && + target[0] == L'\\' && target[1] == L'\\') + return target; + + attr.Length = sizeof(attr); + attr.RootDirectory = NULL; + attr.ObjectName = &name; + attr.Attributes = 0; + attr.SecurityDescriptor = NULL; + attr.SecurityQualityOfService = NULL; + + name.Buffer = (wchar_t *)target; + name.Length = 0; + p = target; + do { + HANDLE h; + const wchar_t *orig_p = p; + + /* Skip non-backslashes */ + while (p != target_end && *p != L'\\') + p++; + + /* Skip backslashes */ + while (p != target_end && *p == L'\\') + p++; + + /* Append path component */ + name.Length += (p - orig_p) * sizeof(wchar_t); + name.MaximumLength = name.Length; + + /* Try opening the file */ + status = (*func_NtOpenFile) (&h, + FILE_READ_ATTRIBUTES | FILE_TRAVERSE, + &attr, + &iosb, + FILE_SHARE_VALID_FLAGS, + FILE_OPEN_FOR_BACKUP_INTENT); + + if (NT_SUCCESS(status)) { + /* Reset root directory */ + if (attr.RootDirectory) + (*func_NtClose)(attr.RootDirectory); + attr.RootDirectory = h; + name.Buffer = (wchar_t *)p; + name.Length = 0; + + if (file_has_ino_and_dev(h, capture_root_ino, + capture_root_dev)) + goto out_close_root_dir; + } + } while (p != target_end); + + p = NULL; + +out_close_root_dir: + if (attr.RootDirectory) + (*func_NtClose)(attr.RootDirectory); + return p; +} + +static int +winnt_rpfix_progress(struct add_image_params *params, const wchar_t *path, + const struct reparse_data *rpdata, + enum wimlib_progress_msg msg) +{ + size_t print_name_nchars = rpdata->print_name_nbytes / sizeof(wchar_t); + wchar_t print_name0[print_name_nchars + 1]; + + wmemcpy(print_name0, rpdata->print_name, print_name_nchars); + print_name0[print_name_nchars] = L'\0'; + + params->progress.scan.cur_path = printable_path(path); + params->progress.scan.symlink_target = print_name0; + return do_capture_progress(params, msg, NULL); } -/* Returns: `enum rp_status' value on success; negative WIMLIB_ERR_* value on - * failure. */ static int -winnt_capture_try_rpfix(u8 *rpbuf, u16 *rpbuflen_p, - u64 capture_root_ino, u64 capture_root_dev, - const wchar_t *path, struct add_image_params *params) +winnt_try_rpfix(u8 *rpbuf, u16 *rpbuflen_p, + u64 capture_root_ino, u64 capture_root_dev, + const wchar_t *path, struct add_image_params *params) { struct reparse_data rpdata; + const wchar_t *rel_target; int ret; - enum rp_status rp_status; - ret = parse_reparse_data(rpbuf, *rpbuflen_p, &rpdata); - if (ret) - return -ret; - - rp_status = winnt_capture_maybe_rpfix_target(rpdata.substitute_name, - &rpdata.substitute_name_nbytes, - capture_root_ino, - capture_root_dev, - le32_to_cpu(*(le32*)rpbuf)); - if (rp_status & RP_FIXED) { - wimlib_assert(rpdata.substitute_name_nbytes % 2 == 0); - utf16lechar substitute_name_copy[rpdata.substitute_name_nbytes / 2]; - wmemcpy(substitute_name_copy, rpdata.substitute_name, - rpdata.substitute_name_nbytes / 2); - rpdata.substitute_name = substitute_name_copy; - rpdata.print_name = substitute_name_copy; - rpdata.print_name_nbytes = rpdata.substitute_name_nbytes; - if (rp_status == RP_FIXED_FULLPATH) { - /* "full path", meaning \??\ prefixed. We should not - * include this prefix in the print name, as it is - * apparently meant for the filesystem driver only. */ - rpdata.print_name += 4; - rpdata.print_name_nbytes -= 8; - } - ret = make_reparse_buffer(&rpdata, rpbuf, rpbuflen_p); - if (ret == 0) - ret = rp_status; - else - ret = -ret; - } else { - if (rp_status == RP_EXCLUDED) { - /* Ignoring absolute symbolic link or junction point - * that points out of the tree to be captured. */ - size_t print_name_nchars = rpdata.print_name_nbytes / 2; - wchar_t print_name0[print_name_nchars + 1]; - print_name0[print_name_nchars] = L'\0'; - wmemcpy(print_name0, rpdata.print_name, print_name_nchars); - - params->progress.scan.cur_path = printable_path(path); - params->progress.scan.symlink_target = print_name0; - do_capture_progress(params, - WIMLIB_SCAN_DENTRY_EXCLUDED_SYMLINK, - NULL); - } - ret = rp_status; + if (parse_reparse_data(rpbuf, *rpbuflen_p, &rpdata)) { + /* Couldn't even understand the reparse data. Don't try the + * fixup. */ + return RP_NOT_FIXED; } - return ret; + + /* + * Don't do reparse point fixups on relative symbolic links. + * + * On Windows, a relative symbolic link is supposed to be identifiable + * by having reparse tag WIM_IO_REPARSE_TAG_SYMLINK and flags + * SYMBOLIC_LINK_RELATIVE. We will use this information, although this + * may not always do what the user expects, since drive-relative + * symbolic links such as "\Users\Public" have SYMBOLIC_LINK_RELATIVE + * set, in addition to truely relative symbolic links such as "Users" or + * "Users\Public". However, WIMGAPI (as of Windows 8.1) has this same + * behavior. + * + * Otherwise, as far as I can tell, the targets of symbolic links that + * are NOT relative, as well as junctions (note: a mountpoint is the + * sames thing as a junction), must be NT namespace paths, for example: + * + * - \??\e:\Users\Public + * - \DosDevices\e:\Users\Public + * - \Device\HardDiskVolume4\Users\Public + * - \??\Volume{c47cb07c-946e-4155-b8f7-052e9cec7628}\Users\Public + * - \DosDevices\Volume{c47cb07c-946e-4155-b8f7-052e9cec7628}\Users\Public + */ + if (rpdata.rptag == WIM_IO_REPARSE_TAG_SYMLINK && + (rpdata.rpflags & SYMBOLIC_LINK_RELATIVE)) + return RP_NOT_FIXED; + + rel_target = winnt_get_root_relative_target(rpdata.substitute_name, + rpdata.substitute_name_nbytes, + capture_root_ino, + capture_root_dev); + if (!rel_target) { + /* Target points outside of the tree being captured. Exclude + * this reparse point from the capture (but inform the library + * user). */ + ret = winnt_rpfix_progress(params, path, &rpdata, + WIMLIB_SCAN_DENTRY_EXCLUDED_SYMLINK); + if (ret) + return ret; + return RP_EXCLUDED; + } + + if (rel_target == rpdata.substitute_name) { + /* Weird target --- keep the reparse point and don't mess with + * it. */ + return RP_NOT_FIXED; + } + + /* We have an absolute target pointing within the directory being + * captured, @rel_target is the suffix of the link target that is the + * part relative to the directory being captured. + * + * We will cut off the prefix before this part (which is the path to the + * directory being captured) and add a dummy prefix. Since the process + * will need to be reversed when applying the image, it shouldn't matter + * what exactly the prefix is, as long as it looks like an absolute + * path. + */ + + { + size_t rel_target_nbytes = + rpdata.substitute_name_nbytes - ((const u8 *)rel_target - + (const u8 *)rpdata.substitute_name); + size_t rel_target_nchars = rel_target_nbytes / sizeof(wchar_t); + + wchar_t tmp[rel_target_nchars + 7]; + + wmemcpy(tmp, L"\\??\\X:\\", 7); + wmemcpy(tmp + 7, rel_target, rel_target_nchars); + + rpdata.substitute_name = tmp; + rpdata.substitute_name_nbytes = rel_target_nbytes + (7 * sizeof(wchar_t)); + rpdata.print_name = tmp + 4; + rpdata.print_name_nbytes = rel_target_nbytes + (3 * sizeof(wchar_t)); + + if (make_reparse_buffer(&rpdata, rpbuf, rpbuflen_p)) + return RP_NOT_FIXED; + } + ret = winnt_rpfix_progress(params, path, &rpdata, + WIMLIB_SCAN_DENTRY_FIXED_SYMLINK); + if (ret) + return ret; + return RP_FIXED; } /* @@ -592,66 +708,57 @@ winnt_capture_try_rpfix(u8 *rpbuf, u16 *rpbuflen_p, * fixing the targets of absolute symbolic links and junction points to be * relative to the root of capture. * - * @h: Open handle to the reparse point. - * @path: Path to the reparse point file. - * @params: Additional parameters, including whether to do reparse point fixups - * or not. - * @rpbuf: Buffer of length at least REPARSE_POINT_MAX_SIZE bytes into which - * the reparse point buffer will be loaded. - * @rpbuflen_ret: On success, the length of the reparse point buffer in bytes - * is written to this location. + * @h: + * Open handle to the reparse point file. + * @path: + * Path to the reparse point file. + * @params: + * Capture parameters. add_flags, capture_root_ino, capture_root_dev, + * progfunc, progctx, and progress are used. + * @rpbuf: + * Buffer of length at least REPARSE_POINT_MAX_SIZE bytes into which the + * reparse point buffer will be loaded. + * @rpbuflen_ret: + * On success, the length of the reparse point buffer in bytes is written + * to this location. * - * Returns: - * On success, returns an `enum rp_status' value that indicates if and/or - * how the reparse point fixup was done. - * - * On failure, returns a negative value that is a negated WIMLIB_ERR_* - * code. + * On success, returns a nonpositive `enum rp_status' value. + * On failure, returns a positive error code. */ static int winnt_get_reparse_data(HANDLE h, const wchar_t *path, struct add_image_params *params, u8 *rpbuf, u16 *rpbuflen_ret) { - DWORD bytesReturned; + DWORD bytes_returned; u32 reparse_tag; int ret; u16 rpbuflen; if (!DeviceIoControl(h, FSCTL_GET_REPARSE_POINT, - NULL, /* "Not used with this operation; set to NULL" */ - 0, /* "Not used with this operation; set to 0" */ - rpbuf, /* "A pointer to a buffer that - receives the reparse point data */ - REPARSE_POINT_MAX_SIZE, /* "The size of the output - buffer, in bytes */ - &bytesReturned, - NULL)) + NULL, 0, rpbuf, REPARSE_POINT_MAX_SIZE, + &bytes_returned, NULL)) { set_errno_from_GetLastError(); - return -WIMLIB_ERR_READ; + return WIMLIB_ERR_READ; } - if (bytesReturned < 8 || bytesReturned > REPARSE_POINT_MAX_SIZE) { + if (unlikely(bytes_returned < 8)) { errno = EINVAL; - return -WIMLIB_ERR_INVALID_REPARSE_DATA; + return WIMLIB_ERR_INVALID_REPARSE_DATA; } - rpbuflen = bytesReturned; + rpbuflen = bytes_returned; reparse_tag = le32_to_cpu(*(le32*)rpbuf); + ret = RP_NOT_FIXED; if (params->add_flags & WIMLIB_ADD_FLAG_RPFIX && (reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK || reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT)) { - /* Try doing reparse point fixup */ - ret = winnt_capture_try_rpfix(rpbuf, - &rpbuflen, - params->capture_root_ino, - params->capture_root_dev, - path, - params); - } else { - ret = RP_NOT_FIXED; + ret = winnt_try_rpfix(rpbuf, &rpbuflen, + params->capture_root_ino, + params->capture_root_dev, + path, params); } *rpbuflen_ret = rpbuflen; return ret; @@ -987,10 +1094,7 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret, if (should_exclude_path(full_path + params->capture_root_nchars, full_path_nchars - params->capture_root_nchars, params->config)) - { - ret = 0; goto out_progress; - } /* Open the file. */ status = winnt_openat(cur_dir, @@ -1096,19 +1200,20 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret, rpbuf = alloca(REPARSE_POINT_MAX_SIZE); ret = winnt_get_reparse_data(h, full_path, params, rpbuf, &rpbuflen); - if (ret < 0) { - /* WIMLIB_ERR_* (inverted) */ - ret = -ret; - ERROR_WITH_ERRNO("\"%ls\": Can't get reparse data", - printable_path(full_path)); - goto out; - } else if (ret & RP_FIXED) { - not_rpfixed = 0; - } else if (ret == RP_EXCLUDED) { + switch (ret) { + case RP_EXCLUDED: ret = 0; goto out; - } else { + case RP_FIXED: + not_rpfixed = 0; + break; + case RP_NOT_FIXED: not_rpfixed = 1; + break; + default: + ERROR_WITH_ERRNO("\"%ls\": Can't get reparse data", + printable_path(full_path)); + goto out; } } @@ -1148,7 +1253,6 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret, if (inode->i_nlink > 1) { /* Shared inode (hard link); skip reading per-inode information. */ - ret = 0; goto out_progress; } @@ -1237,9 +1341,9 @@ winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret, out_progress: params->progress.scan.cur_path = printable_path(full_path); if (likely(root)) - do_capture_progress(params, WIMLIB_SCAN_DENTRY_OK, inode); + ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_OK, inode); else - do_capture_progress(params, WIMLIB_SCAN_DENTRY_EXCLUDED, NULL); + ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_EXCLUDED, NULL); out: if (likely(h != INVALID_HANDLE_VALUE)) (*func_NtClose)(h);