cosmos::SecretFile Class Reference

Memory based files suitable for storing of sensitive secret data. More...

#include <SecretFile.hxx>

Inheritance diagram for cosmos::SecretFile:

Public Member Functions
	SecretFile (const CloseOnExec cloexec)
void	create (const CloseOnExec cloexec=CloseOnExec{true})
	Create a new MemFile using the given settings.
Public Member Functions inherited from cosmos::FileBase
	FileBase (const FileBase &)=delete
FileBase &	operator= (const FileBase &)=delete
virtual void	close ()
	Close the current file object.
bool	isOpen () const
	Returns whether currently a FileDescriptor is opened.
FileDescriptor	fd () const
	Allows access to the underlying fd with const semantics.
void	truncate (const off_t length)
Public Member Functions inherited from cosmos::StreamIO
	StreamIO (FileDescriptor &fd)
	StreamIO (const StreamIO &)=delete
StreamIO &	operator= (const StreamIO &)=delete
StreamIO &	operator= (StreamIO &&) noexcept
size_t	read (void *buf, size_t length)
	Read up to length bytes from the file into buf.
size_t	write (const void *buf, size_t length)
	Write up to length bytes from buf into the underlying file.
size_t	write (const std::string_view data)
	string_view wrapper around write(const void*, size_t).
void	readAll (void *buf, size_t length)
	Read all length bytes from the underlying file.
void	readAll (std::string &s, size_t length)
	Like readAll(void*, size_t) using an STL string.
void	writeAll (const void *buf, size_t length)
	Write all length bytes into the underlying file.
void	writeAll (const std::string_view data)
	string_view wrapper around writeAll(const void*, size_t).
bool	read (ReadIOVector &iovec)
	Read data from file into a vector of data regions.
bool	write (WriteIOVector &iovec)
	Write data to file from a vector of data regions.
void	readAll (ReadIOVector &iovec)
	Read into all data regions specified in iovec.
void	writeAll (WriteIOVector &iovec)
	Write all data regions specified in iovec.
off_t	seek (const SeekType type, off_t off)
	Seek to the given offset based on the given offset type.
off_t	seekFromStart (off_t off)
	Seek to the given offset relative to the start of the file.
off_t	seekFromCurrent (off_t off)
	Seek to the given offset relative to the current file position.
off_t	seekFromEnd (off_t off)
	Seek to the given offset relative to the end of the file.

Additional Inherited Members
Public Types inherited from cosmos::StreamIO
enum class	SeekType : int {   SET = SEEK_SET , CUR = SEEK_CUR , END = SEEK_END , DATA = SEEK_DATA ,   HOLE = SEEK_HOLE }
	Different methods for changing the file read/write position. More...
Protected Member Functions inherited from cosmos::FileBase
	FileBase (const FileDescriptor fd=FileDescriptor{})
	FileBase (FileBase &&other) noexcept
FileBase &	operator= (FileBase &&other) noexcept
Protected Attributes inherited from cosmos::FileBase
FileDescriptor	m_fd
Protected Attributes inherited from cosmos::StreamIO
FileDescriptor &	m_stream_fd

Detailed Description

Memory based files suitable for storing of sensitive secret data.

This type is similar to MemFile, but the file has some special properties that make is suitable for storing sensitive secret data. The memory pages will even we hidden from kernel space to a certain extent. The memory will be locked i.e. it will never be swapped out.

Definition at line 16 of file SecretFile.hxx.

Constructor & Destructor Documentation

SecretFile()

cosmos::SecretFile::SecretFile ( const CloseOnExec cloexec )

inlineexplicit

See also

create().

Definition at line 23 of file SecretFile.hxx.

                                                       {
                create(cloexec);
        }

Member Function Documentation

create()

void cosmos::SecretFile::create

(

const CloseOnExec

cloexec = CloseOnExec{true}

)

Create a new MemFile using the given settings.

Create a new memory file using the given flags and optional page size. The name is only for debugging purposes and is used as an identifier in the /proc file system.

Definition at line 10 of file SecretFile.cxx.

                                                 {
        close();
 
        // this is a rather new system call, be prepared for it's non
        // existence
#ifdef SYS_memfd_secret
        auto fd = ::syscall(SYS_memfd_secret, cloexec ? FD_CLOEXEC : 0);
 
        if (fd == -1) {
                cosmos_throw (ApiError("memfd_secret()"));
        }
 
        m_fd.setFD(FileNum{static_cast<int>(fd)});
#else
        (void)cloexec;
        cosmos_throw (ApiError("memfd_secret()", Errno::NO_SYS));
#endif
}

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The documentation for this class was generated from the following files:

• include/io/SecretFile.hxx
• src/io/SecretFile.cxx