diff options
| -rw-r--r-- | erts/emulator/nifs/win32/win_prim_file.c | 50 |
1 files changed, 48 insertions, 2 deletions
diff --git a/erts/emulator/nifs/win32/win_prim_file.c b/erts/emulator/nifs/win32/win_prim_file.c index 8058350b25..044bee62cf 100644 --- a/erts/emulator/nifs/win32/win_prim_file.c +++ b/erts/emulator/nifs/win32/win_prim_file.c @@ -24,6 +24,7 @@ #include "prim_file_nif.h" +#include <winioctl.h> #include <windows.h> #include <strsafe.h> #include <wchar.h> @@ -671,11 +672,48 @@ static int is_executable_file(const efile_path_t *path) { return 0; } +/* Returns whether the path refers to a link-like object, e.g. a junction + * point, symbolic link, or mounted folder. */ +static int is_name_surrogate(const efile_path_t *path) { + HANDLE handle; + int result; + + handle = CreateFileW((const WCHAR*)path->data, GENERIC_READ, + FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, + FILE_FLAG_OPEN_REPARSE_POINT | + FILE_FLAG_BACKUP_SEMANTICS, + NULL); + result = 0; + + if(handle != INVALID_HANDLE_VALUE) { + REPARSE_GUID_DATA_BUFFER reparse_buffer; + LPDWORD unused_length; + BOOL success; + + success = DeviceIoControl(handle, + FSCTL_GET_REPARSE_POINT, NULL, 0, + &reparse_buffer, sizeof(reparse_buffer), + &unused_length, NULL); + + /* ERROR_MORE_DATA is tolerated since we're guaranteed to have filled + * the field we want. */ + if(success || GetLastError() == ERROR_MORE_DATA) { + result = IsReparseTagNameSurrogate(reparse_buffer.ReparseTag); + } + + CloseHandle(handle); + } + + return result; +} + posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_fileinfo_t *result) { BY_HANDLE_FILE_INFORMATION native_file_info; DWORD attributes; + int is_link; sys_memset(&native_file_info, 0, sizeof(native_file_info)); + is_link = 0; attributes = GetFileAttributesW((WCHAR*)path->data); @@ -696,7 +734,11 @@ posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_ } else { HANDLE handle; - if(follow_links && (attributes & FILE_ATTRIBUTE_REPARSE_POINT)) { + if(attributes & FILE_ATTRIBUTE_REPARSE_POINT) { + is_link = is_name_surrogate(path); + } + + if(follow_links && is_link) { posix_errno_t posix_errno; efile_path_t resolved_path; @@ -737,7 +779,7 @@ posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_ } } - if(attributes & FILE_ATTRIBUTE_REPARSE_POINT) { + if(is_link) { result->type = EFILE_FILETYPE_SYMLINK; /* This should be _S_IFLNK, but the old driver always set * non-directories to _S_IFREG. */ @@ -917,6 +959,10 @@ posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_ return EINVAL; } + if(!is_name_surrogate(path)) { + return EINVAL; + } + posix_errno = internal_read_link(path, &result_bin); if(posix_errno == 0) { |