Disk ARchive  2.5.2
Full featured and portable backup and archiving tool
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Defines
Public Member Functions | Static Public Member Functions
libdar::secu_string Class Reference

class secu_string More...

#include <secu_string.hpp>

Inherits libdar::on_pool.

List of all members.

Public Member Functions

 secu_string (U_I storage_size=0)
 secu_string (const char *ptr, U_I size)
 secu_string (const secu_string &ref)
 the copy constructor
secu_stringoperator= (const secu_string &ref)
 the assignment operator
bool operator!= (const std::string &ref) const
bool operator!= (const secu_string &ref) const
bool operator== (const std::string &ref) const
bool operator== (const secu_string &ref) const
 ~secu_string () throw (Ebug)
 the destructor (set memory to zero before releasing it)
void set (int fd, U_I size)
void append_at (U_I offset, const char *ptr, U_I size)
void append_at (U_I offset, int fd, U_I size)
 append some data to the string
void append (const char *ptr, U_I size)
 append some data at the end of the string
void append (int fd, U_I size)
 append some data at the end of the string
void reduce_string_size_to (U_I pos)
void clear ()
 clear the string (set to an empty string)
void resize (U_I size)
void randomize (U_I size)
const char * c_str () const
 get access to the secure string
char & operator[] (U_I index)
char operator[] (U_I index) const
U_I get_size () const
 get the size of the string
U_I get_allocated_size () const
 get the size of the allocated secure space

Static Public Member Functions

static bool is_string_secured ()

Detailed Description

class secu_string

it manages the allocation/release of a given size block of memory and let the user feed it from a filedescriptor and access to it under with a char* pointer. if more constructor are needed (espetially toward API), tell me, but this is a non-sens to build a secure string from another data structure which is not yet secured, where from the read() method that fetches data directly from a filedescriptor (read() low-level system call) which might be a tty for example

Definition at line 57 of file secu_string.hpp.


Constructor & Destructor Documentation

libdar::secu_string::secu_string ( U_I  storage_size = 0) [inline]

constructor 1

create the allocated string in secure memory

Parameters:
[in]storage_sizeis the amount of secured memory to obtain when creating the object

Definition at line 72 of file secu_string.hpp.

libdar::secu_string::secu_string ( const char *  ptr,
U_I  size 
) [inline]

constructor 2

create the string from a pointer to a (secure) string or from a portion of it

Definition at line 77 of file secu_string.hpp.

References append_at().


Member Function Documentation

void libdar::secu_string::append_at ( U_I  offset,
const char *  ptr,
U_I  size 
)

append some data to the string at a given offset

Parameters:
[in]offsetdefines at which offset in the secu_string will be placed the string to append
[in]ptris the address of the string to append
[in]sizeis the number of byte to append
Note:
this call does not change the allocation size, (unlike read()), it adds the data pointed by the arguments to the object while there is enough place to do so. resize() must be used first to define enough secure memory to append the expected amount of data in one or several call to append.

Referenced by append(), and secu_string().

const char* libdar::secu_string::c_str ( ) const [inline]

get access to the secure string

Returns:
the address of the first byte of the string
Note:
check the "size" method to know how much bytes can be read

Definition at line 144 of file secu_string.hpp.

static bool libdar::secu_string::is_string_secured ( ) [static]

to know if secure memory is available

it is advised that the user program of class secu_string uses this call before using objects of that class and if returned false, advise the user that the necessary support for secure memory is not present, that any sensitive data may be swapped out under heavy memory load and thus may lead secure password to be wrote to disk in clear.

char& libdar::secu_string::operator[] ( U_I  index)

get access to the secure string by index

Note:
index must be in the range [ 0 - size() [ to avoid throwing an exception
void libdar::secu_string::randomize ( U_I  size)

set the string to randomize string of given size

Note:
the given size must be less than allocated size

shorten the string (do not change the allocated size)

Parameters:
[in]posis the length of the string to set, it must be smaller or equal to the current size
void libdar::secu_string::resize ( U_I  size) [inline]

clear and resize the string to the defined allocated size

Parameters:
[in]sizeis the amount of secure memory to allocated

Definition at line 133 of file secu_string.hpp.

void libdar::secu_string::set ( int  fd,
U_I  size 
)

fill the object with data

set at most size bytes of data directly from the filedescriptor,

Parameters:
[in]fdthe filedescriptor to read data from
[in]sizeis the maximum number of byte read
Note:
if current storage size is not larg enough to hold size bytes, allocated secure memory is released and larger allocation of secure memory is done.

The documentation for this class was generated from the following file:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Defines