]> wimlib.net Git - wimlib/blobdiff - src/win32.c
Support for encrypted restore
[wimlib] / src / win32.c
index 40a41e422bab5b7a5bab8cf4632c794b4ca4aca4..3244bb07201713bbf47268662a5b3016a68b4e00 100644 (file)
@@ -29,7 +29,8 @@
 #include <windows.h>
 #include <ntdef.h>
 #include <wchar.h>
-#include <shlwapi.h> /* shlwapi.h for PathMatchSpecW() */
+#include <shlwapi.h> /* for PathMatchSpecW() */
+#include <aclapi.h> /* for SetSecurityInfo() */
 #ifdef ERROR /* windows.h defines this */
 #  undef ERROR
 #endif
@@ -306,6 +307,7 @@ read_win32_encrypted_file_prefix(const struct wim_lookup_table_entry *lte,
        } else {
                export_ctx.buf = NULL;
        }
+       export_ctx.buf_filled = 0;
        export_ctx.bytes_remaining = size;
 
        err = OpenEncryptedFileRawW(lte->file_on_disk, 0, &file_ctx);
@@ -840,6 +842,41 @@ win32_get_reparse_data(HANDLE hFile, const wchar_t *path,
        return status;
 }
 
+static DWORD WINAPI
+win32_tally_encrypted_size_cb(unsigned char *_data, void *_ctx,
+                             unsigned long len)
+{
+       *(u64*)_ctx += len;
+       return ERROR_SUCCESS;
+}
+
+static int
+win32_get_encrypted_file_size(const wchar_t *path, u64 *size_ret)
+{
+       DWORD err;
+       void *file_ctx;
+       int ret;
+
+       *size_ret = 0;
+       err = OpenEncryptedFileRawW(path, 0, &file_ctx);
+       if (err != ERROR_SUCCESS) {
+               ERROR("Failed to open encrypted file \"%ls\" for raw read", path);
+               win32_error(err);
+               return WIMLIB_ERR_OPEN;
+       }
+       err = ReadEncryptedFileRaw(win32_tally_encrypted_size_cb,
+                                  size_ret, file_ctx);
+       if (err != ERROR_SUCCESS) {
+               ERROR("Failed to read raw encrypted data from \"%ls\"", path);
+               win32_error(err);
+               ret = WIMLIB_ERR_READ;
+       } else {
+               ret = 0;
+       }
+       CloseEncryptedFileRaw(file_ctx);
+       return ret;
+}
+
 /* Scans an unnamed or named stream of a Win32 file (not a reparse point
  * stream); calculates its SHA1 message digest and either creates a `struct
  * wim_lookup_table_entry' in memory for it, or uses an existing 'struct
@@ -953,11 +990,17 @@ win32_capture_stream(const wchar_t *path,
        }
        lte->file_on_disk = spath;
        spath = NULL;
-       if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED && !is_named_stream)
+       if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED && !is_named_stream) {
+               u64 encrypted_size;
                lte->resource_location = RESOURCE_WIN32_ENCRYPTED;
-       else
+               ret = win32_get_encrypted_file_size(path, &encrypted_size);
+               if (ret)
+                       goto out_free_spath;
+               lte->resource_entry.original_size = encrypted_size;
+       } else {
                lte->resource_location = RESOURCE_WIN32;
-       lte->resource_entry.original_size = (u64)dat->StreamSize.QuadPart;
+               lte->resource_entry.original_size = (u64)dat->StreamSize.QuadPart;
+       }
 
        u32 stream_id;
        if (is_named_stream) {
@@ -1213,6 +1256,8 @@ win32_build_dentry_tree_recursive(struct wim_dentry **root_ret,
        file_size = ((u64)file_info.nFileSizeHigh << 32) |
                     (u64)file_info.nFileSizeLow;
 
+       CloseHandle(hFile);
+
        /* Capture the unnamed data stream (only should be present for regular
         * files) and any alternate data streams. */
        ret = win32_capture_streams(path,
@@ -1222,7 +1267,7 @@ win32_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                                    file_size,
                                    vol_flags);
        if (ret)
-               goto out_close_handle;
+               goto out;
 
        if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
                /* Reparse point: set the reparse data (which we read already)
@@ -1241,6 +1286,7 @@ win32_build_dentry_tree_recursive(struct wim_dentry **root_ret,
                                              state,
                                              vol_flags);
        }
+       goto out;
 out_close_handle:
        CloseHandle(hFile);
 out:
@@ -1390,27 +1436,44 @@ win32_set_reparse_data(HANDLE h,
                DWORD err = GetLastError();
                ERROR("Failed to set reparse data on \"%ls\"", path);
                win32_error(err);
-               return WIMLIB_ERR_WRITE;
+               if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
+                       return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
+               else if (reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
+                        reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT)
+                       return WIMLIB_ERR_LINK;
+               else
+                       return WIMLIB_ERR_WRITE;
        }
        return 0;
 }
 
 static int
-win32_set_compressed(HANDLE hFile, const wchar_t *path)
+win32_set_compression_state(HANDLE hFile, USHORT format, const wchar_t *path)
 {
-       USHORT format = COMPRESSION_FORMAT_DEFAULT;
        DWORD bytesReturned = 0;
        if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
                             &format, sizeof(USHORT),
                             NULL, 0,
                             &bytesReturned, NULL))
        {
+               DWORD err = GetLastError();
+               if (err == ERROR_INVALID_FUNCTION)
+               {
+                       /* XXX: This can happen if we're extracting an
+                        * unexpected file in an encrypted directory.  The file
+                        * gets its encryption flag set and therefore cannot be
+                        * compressed. */
+                       return 0;
+               }
+
                /* Could be a warning only, but we only call this if the volume
                 * supports compression.  So I'm calling this an error. */
-               DWORD err = GetLastError();
                ERROR("Failed to set compression flag on \"%ls\"", path);
                win32_error(err);
-               return WIMLIB_ERR_WRITE;
+               if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
+                       return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
+               else
+                       return WIMLIB_ERR_WRITE;
        }
        return 0;
 }
@@ -1429,7 +1492,10 @@ win32_set_sparse(HANDLE hFile, const wchar_t *path)
                DWORD err = GetLastError();
                WARNING("Failed to set sparse flag on \"%ls\"", path);
                win32_error(err);
-               return WIMLIB_ERR_WRITE;
+               if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
+                       return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
+               else
+                       return WIMLIB_ERR_WRITE;
        }
        return 0;
 }
@@ -1439,21 +1505,55 @@ win32_set_sparse(HANDLE hFile, const wchar_t *path)
  */
 static int
 win32_set_security_data(const struct wim_inode *inode,
+                       HANDLE hFile,
                        const wchar_t *path,
                        struct apply_args *args)
 {
        PSECURITY_DESCRIPTOR descriptor;
        unsigned long n;
        DWORD err;
+       const struct wim_security_data *sd;
+
+       SECURITY_INFORMATION securityInformation = 0;
+
+       void *owner = NULL;
+       void *group = NULL;
+       ACL *dacl = NULL;
+       ACL *sacl = NULL;
+
+       BOOL owner_defaulted;
+       BOOL group_defaulted;
+       BOOL dacl_present;
+       BOOL dacl_defaulted;
+       BOOL sacl_present;
+       BOOL sacl_defaulted;
+
+       sd = wim_const_security_data(args->w);
+       descriptor = sd->descriptors[inode->i_security_id];
+
+       GetSecurityDescriptorOwner(descriptor, &owner, &owner_defaulted);
+       if (owner)
+               securityInformation |= OWNER_SECURITY_INFORMATION;
 
-       descriptor = wim_const_security_data(args->w)->descriptors[inode->i_security_id];
+       GetSecurityDescriptorGroup(descriptor, &group, &group_defaulted);
+       if (group)
+               securityInformation |= GROUP_SECURITY_INFORMATION;
+
+       GetSecurityDescriptorDacl(descriptor, &dacl_present,
+                                 &dacl, &dacl_defaulted);
+       if (dacl)
+               securityInformation |= DACL_SECURITY_INFORMATION;
+
+       GetSecurityDescriptorSacl(descriptor, &sacl_present,
+                                 &sacl, &sacl_defaulted);
+       if (sacl)
+               securityInformation |= SACL_SECURITY_INFORMATION;
 
-       SECURITY_INFORMATION securityInformation = DACL_SECURITY_INFORMATION |
-                                                  SACL_SECURITY_INFORMATION |
-                                                  OWNER_SECURITY_INFORMATION |
-                                                  GROUP_SECURITY_INFORMATION;
 again:
-       if (SetFileSecurityW(path, securityInformation, descriptor))
+       if (securityInformation == 0)
+               return 0;
+       if (SetSecurityInfo(hFile, SE_FILE_OBJECT,
+                           securityInformation, owner, group, dacl, sacl))
                return 0;
        err = GetLastError();
        if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
@@ -1463,6 +1563,7 @@ again:
                if (securityInformation & SACL_SECURITY_INFORMATION) {
                        n = args->num_set_sacl_priv_notheld++;
                        securityInformation &= ~SACL_SECURITY_INFORMATION;
+                       sacl = NULL;
                        if (n < MAX_SET_SACL_PRIV_NOTHELD_WARNINGS) {
                                WARNING(
 "We don't have enough privileges to set the full security\n"
@@ -1502,7 +1603,10 @@ again:
 fail:
                ERROR("Failed to set security descriptor on \"%ls\"", path);
                win32_error(err);
-               return WIMLIB_ERR_WRITE;
+               if (err == ERROR_ACCESS_DENIED || err == ERROR_PRIVILEGE_NOT_HELD)
+                       return WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT;
+               else
+                       return WIMLIB_ERR_WRITE;
        }
 }
 
@@ -1533,12 +1637,159 @@ do_win32_extract_stream(HANDLE hStream, struct wim_lookup_table_entry *lte)
                                    win32_extract_chunk, hStream);
 }
 
+struct win32_encrypted_extract_ctx {
+       void *file_ctx;
+       int wimlib_err_code;
+       bool done;
+       pthread_cond_t cond;
+       pthread_mutex_t mutex;
+       u8 buf[WIM_CHUNK_SIZE];
+       size_t buf_filled;
+};
+
+static DWORD WINAPI
+win32_encrypted_import_cb(unsigned char *data, void *_ctx,
+                         unsigned long *len_p)
+{
+       struct win32_encrypted_extract_ctx *ctx = _ctx;
+       unsigned long len = *len_p;
+
+       pthread_mutex_lock(&ctx->mutex);
+       while (len) {
+               size_t bytes_to_copy;
+
+               DEBUG("Importing up to %lu more bytes of raw encrypted data", len);
+               while (ctx->buf_filled == 0) {
+                       if (ctx->done)
+                               goto out;
+                       pthread_cond_wait(&ctx->cond, &ctx->mutex);
+               }
+               bytes_to_copy = min(len, ctx->buf_filled);
+               memcpy(data, ctx->buf, bytes_to_copy);
+               len -= bytes_to_copy;
+               data += bytes_to_copy;
+               ctx->buf_filled -= bytes_to_copy;
+               memmove(ctx->buf, ctx->buf + bytes_to_copy, ctx->buf_filled);
+               pthread_cond_signal(&ctx->cond);
+       }
+out:
+       *len_p -= len;
+       pthread_mutex_unlock(&ctx->mutex);
+       return ERROR_SUCCESS;
+}
+
+static void *
+win32_encrypted_import_proc(void *arg)
+{
+       struct win32_encrypted_extract_ctx *ctx = arg;
+       DWORD ret;
+       ret = WriteEncryptedFileRaw(win32_encrypted_import_cb, ctx,
+                                   ctx->file_ctx);
+       pthread_mutex_lock(&ctx->mutex);
+       if (ret == ERROR_SUCCESS)
+               ctx->wimlib_err_code = 0;
+       else {
+               win32_error(ret);
+               ctx->wimlib_err_code = WIMLIB_ERR_WRITE;
+       }
+       ctx->done = true;
+       pthread_mutex_unlock(&ctx->mutex);
+       return NULL;
+}
+
+
+static int
+win32_extract_raw_encrypted_chunk(const void *buf, size_t len, void *arg)
+{
+       struct win32_encrypted_extract_ctx *ctx = arg;
+       size_t bytes_to_copy;
+
+       while (len) {
+               DEBUG("Extracting up to %zu more bytes of encrypted data", len);
+               pthread_mutex_lock(&ctx->mutex);
+               while (!ctx->done && ctx->buf_filled == WIM_CHUNK_SIZE)
+                       pthread_cond_wait(&ctx->cond, &ctx->mutex);
+               if (ctx->done) {
+                       pthread_mutex_unlock(&ctx->mutex);
+                       return ctx->wimlib_err_code;
+               }
+               bytes_to_copy = min(len, WIM_CHUNK_SIZE - ctx->buf_filled);
+               memcpy(&ctx->buf[ctx->buf_filled], buf, bytes_to_copy);
+               len -= bytes_to_copy;
+               buf += bytes_to_copy;
+               ctx->buf_filled += bytes_to_copy;
+               pthread_cond_signal(&ctx->cond);
+               pthread_mutex_unlock(&ctx->mutex);
+       }
+       return 0;
+}
+
 static int
 do_win32_extract_encrypted_stream(const wchar_t *path,
                                  const struct wim_lookup_table_entry *lte)
 {
-       ERROR("Extracting encryted streams not implemented");
-       return WIMLIB_ERR_INVALID_PARAM;
+       struct win32_encrypted_extract_ctx ctx;
+       void *file_ctx;
+       pthread_t import_thread;
+       int ret;
+       int ret2;
+
+       DEBUG("Opening file \"%ls\" to extract raw encrypted data", path);
+
+       ret = OpenEncryptedFileRawW(path, CREATE_FOR_IMPORT, &file_ctx);
+       if (ret) {
+               ERROR("Failed to open \"%ls\" to write raw encrypted data", path);
+               win32_error(ret);
+               return WIMLIB_ERR_OPEN;
+       }
+
+       ctx.file_ctx = file_ctx;
+       ctx.buf_filled = 0;
+       ctx.done = false;
+       ctx.wimlib_err_code = 0;
+       if (pthread_mutex_init(&ctx.mutex, NULL)) {
+               ERROR_WITH_ERRNO("Can't create mutex");
+               ret = WIMLIB_ERR_NOMEM;
+               goto out_close;
+       }
+       if (pthread_cond_init(&ctx.cond, NULL)) {
+               ERROR_WITH_ERRNO("Can't create condition variable");
+               ret = WIMLIB_ERR_NOMEM;
+               goto out_pthread_mutex_destroy;
+       }
+       ret = pthread_create(&import_thread, NULL,
+                            win32_encrypted_import_proc, &ctx);
+       if (ret) {
+               errno = ret;
+               ERROR_WITH_ERRNO("Failed to create thread");
+               ret = WIMLIB_ERR_FORK;
+               goto out_pthread_cond_destroy;
+       }
+
+       ret = extract_wim_resource(lte, wim_resource_size(lte),
+                                  win32_extract_raw_encrypted_chunk, &ctx);
+       pthread_mutex_lock(&ctx.mutex);
+       ctx.done = true;
+       pthread_cond_signal(&ctx.cond);
+       pthread_mutex_unlock(&ctx.mutex);
+       ret2 = pthread_join(import_thread, NULL);
+       if (ret2) {
+               errno = ret2;
+               ERROR_WITH_ERRNO("Failed to join encrypted import thread");
+               if (ret == 0)
+                       ret = WIMLIB_ERR_WRITE;
+       }
+       if (ret == 0)
+               ret = ctx.wimlib_err_code;
+out_pthread_cond_destroy:
+       pthread_cond_destroy(&ctx.cond);
+out_pthread_mutex_destroy:
+       pthread_mutex_destroy(&ctx.mutex);
+out_close:
+       CloseEncryptedFileRaw(file_ctx);
+       if (ret)
+               ERROR("Failed to extract encrypted file \"%ls\"", path);
+       return ret;
 }
 
 static bool
@@ -1558,11 +1809,27 @@ path_is_root_of_drive(const wchar_t *path)
        return (*path == L'\0');
 }
 
-static DWORD
-win32_get_create_flags_and_attributes(DWORD i_attributes)
+static inline DWORD
+win32_mask_attributes(DWORD i_attributes)
 {
-       DWORD attributes;
+       return i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
+                               FILE_ATTRIBUTE_COMPRESSED |
+                               FILE_ATTRIBUTE_REPARSE_POINT |
+                               FILE_ATTRIBUTE_DIRECTORY |
+                               FILE_ATTRIBUTE_ENCRYPTED |
+                               FILE_FLAG_DELETE_ON_CLOSE |
+                               FILE_FLAG_NO_BUFFERING |
+                               FILE_FLAG_OPEN_NO_RECALL |
+                               FILE_FLAG_OVERLAPPED |
+                               FILE_FLAG_RANDOM_ACCESS |
+                               /*FILE_FLAG_SESSION_AWARE |*/
+                               FILE_FLAG_SEQUENTIAL_SCAN |
+                               FILE_FLAG_WRITE_THROUGH);
+}
 
+static inline DWORD
+win32_get_create_flags_and_attributes(DWORD i_attributes)
+{
        /*
         * Some attributes cannot be set by passing them to CreateFile().  In
         * particular:
@@ -1587,29 +1854,9 @@ win32_get_create_flags_and_attributes(DWORD i_attributes)
         * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
         * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
         */
-       attributes = i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
-                                     FILE_ATTRIBUTE_COMPRESSED |
-                                     FILE_ATTRIBUTE_REPARSE_POINT |
-                                     FILE_ATTRIBUTE_DIRECTORY |
-                                     FILE_FLAG_DELETE_ON_CLOSE |
-                                     FILE_FLAG_NO_BUFFERING |
-                                     FILE_FLAG_OPEN_NO_RECALL |
-                                     FILE_FLAG_OVERLAPPED |
-                                     FILE_FLAG_RANDOM_ACCESS |
-                                     /*FILE_FLAG_SESSION_AWARE |*/
-                                     FILE_FLAG_SEQUENTIAL_SCAN |
-                                     FILE_FLAG_WRITE_THROUGH);
-       return attributes |
-              FILE_FLAG_OPEN_REPARSE_POINT |
-              FILE_FLAG_BACKUP_SEMANTICS;
-}
-
-static bool
-inode_has_special_attributes(const struct wim_inode *inode)
-{
-       return (inode->i_attributes & (FILE_ATTRIBUTE_COMPRESSED |
-                                      FILE_ATTRIBUTE_REPARSE_POINT |
-                                      FILE_ATTRIBUTE_SPARSE_FILE)) != 0;
+       return win32_mask_attributes(i_attributes) |
+               FILE_FLAG_OPEN_REPARSE_POINT |
+               FILE_FLAG_BACKUP_SEMANTICS;
 }
 
 /* Set compression or sparse attributes, and reparse data, if supported by the
@@ -1621,16 +1868,26 @@ win32_set_special_attributes(HANDLE hFile, const struct wim_inode *inode,
 {
        int ret;
 
-       if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
+       /* Encrypted files cannot be [de]compressed. */
+       if (!(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)) {
                if (vol_flags & FILE_FILE_COMPRESSION) {
-                       DEBUG("Setting compression flag on \"%ls\"", path);
-                       ret = win32_set_compressed(hFile, path);
+                       USHORT format;
+                       if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
+                               format = COMPRESSION_FORMAT_DEFAULT;
+                               DEBUG("Setting compression flag on \"%ls\"", path);
+                       } else {
+                               format = COMPRESSION_FORMAT_NONE;
+                               DEBUG("Clearing compression flag on \"%ls\"", path);
+                       }
+                       ret = win32_set_compression_state(hFile, format, path);
                        if (ret)
                                return ret;
                } else {
-                       DEBUG("Cannot set compression attribute on \"%ls\": "
-                             "volume does not support transparent compression",
-                             path);
+                       if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
+                               DEBUG("Cannot set compression attribute on \"%ls\": "
+                                     "volume does not support transparent compression",
+                                     path);
+                       }
                }
        }
 
@@ -1659,7 +1916,72 @@ win32_set_special_attributes(HANDLE hFile, const struct wim_inode *inode,
                              "does not support reparse points", path);
                }
        }
+       return 0;
+}
+
+static int
+win32_begin_extract_unnamed_stream(const struct wim_inode *inode,
+                                  const struct wim_lookup_table_entry *lte,
+                                  const wchar_t *path,
+                                  DWORD *creationDisposition_ret,
+                                  unsigned int vol_flags)
+{
+       DWORD err;
+       int ret;
 
+       /* Directories must be created with CreateDirectoryW().  Then
+        * the call to CreateFileW() will merely open the directory that
+        * was already created rather than creating a new file. */
+       if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
+               if (!CreateDirectoryW(path, NULL)) {
+                       err = GetLastError();
+                       switch (err) {
+                       case ERROR_ALREADY_EXISTS:
+                               break;
+                       case ERROR_ACCESS_DENIED:
+                               if (path_is_root_of_drive(path))
+                                       break;
+                               /* Fall through */
+                       default:
+                               ERROR("Failed to create directory \"%ls\"",
+                                     path);
+                               win32_error(err);
+                               return WIMLIB_ERR_MKDIR;
+                       }
+               }
+               DEBUG("Created directory \"%ls\"", path);
+               *creationDisposition_ret = OPEN_EXISTING;
+       }
+       if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
+           vol_flags & FILE_SUPPORTS_ENCRYPTION)
+       {
+               if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
+                       if (!EncryptFile(path)) {
+                               err = GetLastError();
+                               ERROR("Failed to encrypt directory \"%ls\"",
+                                     path);
+                               win32_error(err);
+                               return WIMLIB_ERR_WRITE;
+                       }
+               } else {
+                       ret = do_win32_extract_encrypted_stream(path, lte);
+                       if (ret)
+                               return ret;
+                       DEBUG("Extracted encrypeted file \"%ls\"", path);
+                       *creationDisposition_ret = OPEN_EXISTING;
+               }
+       }
+       if (*creationDisposition_ret == OPEN_EXISTING)
+       {
+               if (!SetFileAttributesW(path,
+                                       win32_mask_attributes(inode->i_attributes)))
+               {
+                       err = GetLastError();
+                       ERROR("Failed to set attributes on \"%ls\"", path);
+                       win32_error(err);
+                       return WIMLIB_ERR_WRITE;
+               }
+       }
        return 0;
 }
 
@@ -1668,17 +1990,18 @@ win32_extract_stream(const struct wim_inode *inode,
                     const wchar_t *path,
                     const wchar_t *stream_name_utf16,
                     struct wim_lookup_table_entry *lte,
-                    unsigned vol_flags)
+                    struct apply_args *args)
 {
        wchar_t *stream_path;
        HANDLE h;
        int ret;
        DWORD err;
        DWORD creationDisposition = CREATE_ALWAYS;
+       DWORD requestedAccess;
 
        if (stream_name_utf16) {
                /* Named stream.  Create a buffer that contains the UTF-16LE
-                * string [.\]@path:@stream_name_utf16.  This is needed to
+                * string [./]path:stream_name_utf16.  This is needed to
                 * create and open the stream using CreateFileW().  I'm not
                 * aware of any other APIs to do this.  Note: the '$DATA' suffix
                 * seems to be unneeded.  Additional note: a "./" prefix needs
@@ -1710,41 +2033,19 @@ win32_extract_stream(const struct wim_inode *inode,
                 * */
                stream_path = (wchar_t*)path;
 
-               /* Directories must be created with CreateDirectoryW().  Then
-                * the call to CreateFileW() will merely open the directory that
-                * was already created rather than creating a new file. */
-               if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
-                       if (!CreateDirectoryW(stream_path, NULL)) {
-                               err = GetLastError();
-                               switch (err) {
-                               case ERROR_ALREADY_EXISTS:
-                                       break;
-                               case ERROR_ACCESS_DENIED:
-                                       if (path_is_root_of_drive(path))
-                                               break;
-                                       /* Fall through */
-                               default:
-                                       ERROR("Failed to create directory \"%ls\"",
-                                             stream_path);
-                                       win32_error(err);
-                                       ret = WIMLIB_ERR_MKDIR;
-                                       goto fail;
-                               }
-                       }
-                       DEBUG("Created directory \"%ls\"", stream_path);
-                       if (!inode_has_special_attributes(inode)) {
-                               ret = 0;
-                               goto out;
-                       }
-                       DEBUG("Directory \"%ls\" has special attributes!",
-                             stream_path);
-                       creationDisposition = OPEN_EXISTING;
-               }
+               ret = win32_begin_extract_unnamed_stream(inode, lte, path,
+                                                        &creationDisposition,
+                                                        args->vol_flags);
+               if (ret)
+                       goto fail;
        }
 
        DEBUG("Opening \"%ls\"", stream_path);
+       requestedAccess = GENERIC_READ | GENERIC_WRITE |
+                         ACCESS_SYSTEM_SECURITY;
+try_open_again:
        h = CreateFileW(stream_path,
-                       GENERIC_READ | GENERIC_WRITE,
+                       requestedAccess,
                        0,
                        NULL,
                        creationDisposition,
@@ -1752,35 +2053,41 @@ win32_extract_stream(const struct wim_inode *inode,
                        NULL);
        if (h == INVALID_HANDLE_VALUE) {
                err = GetLastError();
+               if (err == ERROR_PRIVILEGE_NOT_HELD &&
+                   (requestedAccess & ACCESS_SYSTEM_SECURITY))
+               {
+                       requestedAccess &= ~ACCESS_SYSTEM_SECURITY;
+                       goto try_open_again;
+               }
                ERROR("Failed to create \"%ls\"", stream_path);
                win32_error(err);
                ret = WIMLIB_ERR_OPEN;
                goto fail;
        }
 
-       if (stream_name_utf16 == NULL && inode_has_special_attributes(inode)) {
+       if (stream_name_utf16 == NULL) {
+               if (inode->i_security_id >= 0 &&
+                   !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
+                   && (args->vol_flags & FILE_PERSISTENT_ACLS))
+               {
+                       ret = win32_set_security_data(inode, h, path, args);
+                       if (ret)
+                               goto fail_close_handle;
+               }
+
                ret = win32_set_special_attributes(h, inode, lte, path,
-                                                  vol_flags);
+                                                  args->vol_flags);
                if (ret)
                        goto fail_close_handle;
        }
 
-       if (!(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
-               if (lte) {
-                       DEBUG("Extracting \"%ls\" (len = %"PRIu64")",
-                             stream_path, wim_resource_size(lte));
-                       if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED
-                           && stream_name_utf16 == NULL
-                           && (vol_flags & FILE_SUPPORTS_ENCRYPTION))
-                       {
-                               ret = do_win32_extract_encrypted_stream(stream_path,
-                                                                       lte);
-                       } else {
-                               ret = do_win32_extract_stream(h, lte);
-                       }
-                       if (ret)
-                               goto fail_close_handle;
-               }
+       if (!(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
+           lte != NULL &&
+           creationDisposition != OPEN_EXISTING)
+       {
+               DEBUG("Extracting \"%ls\" (len = %"PRIu64")",
+                     stream_path, wim_resource_size(lte));
+               ret = do_win32_extract_stream(h, lte);
        }
 
        DEBUG("Closing \"%ls\"", stream_path);
@@ -1796,7 +2103,7 @@ win32_extract_stream(const struct wim_inode *inode,
 fail_close_handle:
        CloseHandle(h);
 fail:
-       ERROR("Error extracting %ls", stream_path);
+       ERROR("Error extracting \"%ls\"", stream_path);
 out:
        return ret;
 }
@@ -1804,56 +2111,151 @@ out:
 /*
  * Creates a file, directory, or reparse point and extracts all streams to it
  * (unnamed data stream and/or reparse point stream, plus any alternate data
- * streams).  This in Win32-specific code.
+ * streams).
  *
  * @inode:     WIM inode for this file or directory.
  * @path:      UTF-16LE external path to extract the inode to.
+ * @args:      Additional extraction context.
  *
  * Returns 0 on success; nonzero on failure.
  */
 static int
 win32_extract_streams(const struct wim_inode *inode,
-                     const wchar_t *path, u64 *completed_bytes_p,
-                     unsigned vol_flags)
+                     const wchar_t *path, struct apply_args *args)
 {
        struct wim_lookup_table_entry *unnamed_lte;
        int ret;
 
+       /* Extract the unnamed stream. */
+
        unnamed_lte = inode_unnamed_lte_resolved(inode);
-       ret = win32_extract_stream(inode, path, NULL, unnamed_lte,
-                                  vol_flags);
+       ret = win32_extract_stream(inode, path, NULL, unnamed_lte, args);
        if (ret)
                goto out;
        if (unnamed_lte && inode->i_extracted_file == NULL)
-               *completed_bytes_p += wim_resource_size(unnamed_lte);
+       {
+               args->progress.extract.completed_bytes +=
+                       wim_resource_size(unnamed_lte);
+       }
+
+       /* Extract any named streams, if supported by the volume. */
 
-       if (!(vol_flags & FILE_NAMED_STREAMS))
+       if (!(args->vol_flags & FILE_NAMED_STREAMS))
                goto out;
        for (u16 i = 0; i < inode->i_num_ads; i++) {
                const struct wim_ads_entry *ads_entry = &inode->i_ads_entries[i];
-               if (ads_entry->stream_name_nbytes != 0) {
-                       /* Skip special UNIX data entries (see documentation for
-                        * WIMLIB_ADD_IMAGE_FLAG_UNIX_DATA) */
-                       if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
-                           && !memcmp(ads_entry->stream_name,
-                                      WIMLIB_UNIX_DATA_TAG_UTF16LE,
-                                      WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
-                               continue;
-                       ret = win32_extract_stream(inode,
-                                                  path,
-                                                  ads_entry->stream_name,
-                                                  ads_entry->lte,
-                                                  vol_flags);
-                       if (ret)
-                               break;
-                       if (ads_entry->lte && inode->i_extracted_file == NULL)
-                               *completed_bytes_p += wim_resource_size(ads_entry->lte);
+
+               /* Skip the unnamed stream if it's in the ADS entries (we
+                * already extracted it...) */
+               if (ads_entry->stream_name_nbytes == 0)
+                       continue;
+
+               /* Skip special UNIX data entries (see documentation for
+                * WIMLIB_ADD_IMAGE_FLAG_UNIX_DATA) */
+               if (ads_entry->stream_name_nbytes == WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES
+                   && !memcmp(ads_entry->stream_name,
+                              WIMLIB_UNIX_DATA_TAG_UTF16LE,
+                              WIMLIB_UNIX_DATA_TAG_UTF16LE_NBYTES))
+                       continue;
+
+               /* Extract the named stream */
+               ret = win32_extract_stream(inode,
+                                          path,
+                                          ads_entry->stream_name,
+                                          ads_entry->lte,
+                                          args);
+               if (ret)
+                       break;
+
+               /* Tally the bytes extracted, unless this was supposed to be a
+                * hard link and we are extracting the data again only as a
+                * fallback. */
+               if (ads_entry->lte && inode->i_extracted_file == NULL)
+               {
+                       args->progress.extract.completed_bytes +=
+                               wim_resource_size(ads_entry->lte);
                }
        }
 out:
        return ret;
 }
 
+static int
+win32_check_vol_flags(const wchar_t *output_path, struct apply_args *args)
+{
+       if (args->have_vol_flags)
+               return 0;
+
+       win32_get_vol_flags(output_path, &args->vol_flags);
+       args->have_vol_flags = true;
+       /* Warn the user about data that may not be extracted. */
+       if (!(args->vol_flags & FILE_SUPPORTS_SPARSE_FILES))
+               WARNING("Volume does not support sparse files!\n"
+                       "          Sparse files will be extracted as non-sparse.");
+       if (!(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
+               WARNING("Volume does not support reparse points!\n"
+                       "          Reparse point data will not be extracted.");
+       if (!(args->vol_flags & FILE_NAMED_STREAMS)) {
+               WARNING("Volume does not support named data streams!\n"
+                       "          Named data streams will not be extracted.");
+       }
+       if (!(args->vol_flags & FILE_SUPPORTS_ENCRYPTION)) {
+               WARNING("Volume does not support encryption!\n"
+                       "          Encrypted files will be extracted as raw data.");
+       }
+       if (!(args->vol_flags & FILE_FILE_COMPRESSION)) {
+               WARNING("Volume does not support transparent compression!\n"
+                       "          Compressed files will be extracted as non-compressed.");
+       }
+       if (!(args->vol_flags & FILE_PERSISTENT_ACLS)) {
+               if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
+                       ERROR("Strict ACLs requested, but the volume does not "
+                             "support ACLs!");
+                       return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
+               } else {
+                       WARNING("Volume does not support persistent ACLS!\n"
+                               "          File permissions will not be extracted.");
+               }
+       }
+       return 0;
+}
+
+static int
+win32_try_hard_link(const wchar_t *output_path, const struct wim_inode *inode,
+                   struct apply_args *args)
+{
+       DWORD err;
+
+       /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
+        * but it's only available on Windows 7 and later.  So no use
+        * even checking it, really.  Instead, CreateHardLinkW() will
+        * apparently return ERROR_INVALID_FUNCTION if the volume does
+        * not support hard links. */
+       DEBUG("Creating hard link \"%ls => %ls\"",
+             output_path, inode->i_extracted_file);
+       if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
+               return 0;
+
+       err = GetLastError();
+       if (err != ERROR_INVALID_FUNCTION) {
+               ERROR("Can't create hard link \"%ls => %ls\"",
+                     output_path, inode->i_extracted_file);
+               win32_error(err);
+               return WIMLIB_ERR_LINK;
+       } else {
+               args->num_hard_links_failed++;
+               if (args->num_hard_links_failed < MAX_CREATE_HARD_LINK_WARNINGS) {
+                       WARNING("Can't create hard link \"%ls => %ls\":\n"
+                               "          Volume does not support hard links!\n"
+                               "          Falling back to extracting a copy of the file.",
+                               output_path, inode->i_extracted_file);
+               } else if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS) {
+                       WARNING("Suppressing further hard linking warnings...");
+               }
+               return -1;
+       }
+}
+
 /* Extract a file, directory, reparse point, or hard link to an
  * already-extracted file using the Win32 API */
 int
@@ -1864,73 +2266,17 @@ win32_do_apply_dentry(const wchar_t *output_path,
 {
        int ret;
        struct wim_inode *inode = dentry->d_inode;
-       DWORD err;
-
-       if (!args->have_vol_flags) {
-               win32_get_vol_flags(output_path, &args->vol_flags);
-               args->have_vol_flags = true;
-               /* Warn the user about data that may not be extracted. */
-               if (!(args->vol_flags & FILE_SUPPORTS_SPARSE_FILES))
-                       WARNING("Volume does not support sparse files!\n"
-                               "          Sparse files will be extracted as non-sparse.");
-               if (!(args->vol_flags & FILE_SUPPORTS_REPARSE_POINTS))
-                       WARNING("Volume does not support reparse points!\n"
-                               "          Reparse point data will not be extracted.");
-               if (!(args->vol_flags & FILE_NAMED_STREAMS)) {
-                       WARNING("Volume does not support named data streams!\n"
-                               "          Named data streams will not be extracted.");
-               }
-               if (!(args->vol_flags & FILE_SUPPORTS_ENCRYPTION)) {
-                       WARNING("Volume does not support encryption!\n"
-                               "          Encrypted files will be extracted as raw data.");
-               }
-               if (!(args->vol_flags & FILE_FILE_COMPRESSION)) {
-                       WARNING("Volume does not support transparent compression!\n"
-                               "          Compressed files will be extracted as non-compressed.");
-               }
-               if (!(args->vol_flags & FILE_PERSISTENT_ACLS)) {
-                       if (args->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
-                               ERROR("Strict ACLs requested, but the volume does not "
-                                     "support ACLs!");
-                               return WIMLIB_ERR_VOLUME_LACKS_FEATURES;
-                       } else {
-                               WARNING("Volume does not support persistent ACLS!\n"
-                                       "          File permissions will not be extracted.");
-                       }
-               }
-       }
 
+       ret = win32_check_vol_flags(output_path, args);
+       if (ret)
+               return ret;
        if (inode->i_nlink > 1 && inode->i_extracted_file != NULL) {
                /* Linked file, with another name already extracted.  Create a
                 * hard link. */
-
-               /* There is a volume flag for this (FILE_SUPPORTS_HARD_LINKS),
-                * but it's only available on Windows 7 and later.  So no use
-                * even checking it, really.  Instead, CreateHardLinkW() will
-                * apparently return ERROR_INVALID_FUNCTION if the volume does
-                * not support hard links. */
-               DEBUG("Creating hard link \"%ls => %ls\"",
-                     output_path, inode->i_extracted_file);
-               if (CreateHardLinkW(output_path, inode->i_extracted_file, NULL))
-                       return 0;
-
-               err = GetLastError();
-               if (err != ERROR_INVALID_FUNCTION) {
-                       ERROR("Can't create hard link \"%ls => %ls\"",
-                             output_path, inode->i_extracted_file);
-                       win32_error(err);
-                       return WIMLIB_ERR_LINK;
-               } else {
-                       args->num_hard_links_failed++;
-                       if (args->num_hard_links_failed < MAX_CREATE_HARD_LINK_WARNINGS) {
-                               WARNING("Can't create hard link \"%ls => %ls\":\n"
-                                       "          Volume does not support hard links!\n"
-                                       "          Falling back to extracting a copy of the file.",
-                                       output_path, inode->i_extracted_file);
-                       } else if (args->num_hard_links_failed == MAX_CREATE_HARD_LINK_WARNINGS) {
-                               WARNING("Suppressing further hard linking warnings...");
-                       }
-               }
+               ret = win32_try_hard_link(output_path, inode, args);
+               if (ret >= 0)
+                       return ret;
+               /* Falling back to extracting copy of file */
        }
 
        if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
@@ -1948,20 +2294,10 @@ win32_do_apply_dentry(const wchar_t *output_path,
 
        /* Create the file, directory, or reparse point, and extract the
         * data streams. */
-       ret = win32_extract_streams(inode, output_path,
-                                   &args->progress.extract.completed_bytes,
-                                   args->vol_flags);
+       ret = win32_extract_streams(inode, output_path, args);
        if (ret)
                return ret;
 
-       if (inode->i_security_id >= 0 &&
-           !(args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
-           && (args->vol_flags & FILE_PERSISTENT_ACLS))
-       {
-               ret = win32_set_security_data(inode, output_path, args);
-               if (ret)
-                       return ret;
-       }
        if (inode->i_nlink > 1) {
                /* Save extracted path for a later call to
                 * CreateHardLinkW() if this inode has multiple links.
@@ -1970,7 +2306,7 @@ win32_do_apply_dentry(const wchar_t *output_path,
                if (!inode->i_extracted_file)
                        ret = WIMLIB_ERR_NOMEM;
        }
-       return 0;
+       return ret;
 }
 
 /* Set timestamps on an extracted file using the Win32 API */