mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
ef3f621ed5
CLA: trivial Reviewed-by: Richard Levitte <levitte@openssl.org> Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/2238)
124 lines
4.4 KiB
Plaintext
124 lines
4.4 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
CRYPTO_secure_malloc_init, CRYPTO_secure_malloc_initialized,
|
|
CRYPTO_secure_malloc_done, OPENSSL_secure_malloc, CRYPTO_secure_malloc,
|
|
OPENSSL_secure_zalloc, CRYPTO_secure_zalloc, OPENSSL_secure_free,
|
|
CRYPTO_secure_free, OPENSSL_secure_actual_size, OPENSSL_secure_allocated,
|
|
CRYPTO_secure_used - secure heap storage
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/crypto.h>
|
|
|
|
int CRYPTO_secure_malloc_init(size_t size, int minsize);
|
|
|
|
int CRYPTO_secure_malloc_initialized();
|
|
|
|
int CRYPTO_secure_malloc_done();
|
|
|
|
void *OPENSSL_secure_malloc(size_t num);
|
|
void *CRYPTO_secure_malloc(size_t num, const char *file, int line);
|
|
|
|
void *OPENSSL_secure_zalloc(size_t num);
|
|
void *CRYPTO_secure_zalloc(size_t num, const char *file, int line);
|
|
|
|
void OPENSSL_secure_free(void* ptr);
|
|
void CRYPTO_secure_free(void *ptr, const char *, int);
|
|
|
|
size_t OPENSSL_secure_actual_size(const void *ptr);
|
|
int OPENSSL_secure_allocated(const void *ptr);
|
|
|
|
size_t CRYPTO_secure_used();
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
In order to help protect applications (particularly long-running servers)
|
|
from pointer overruns or underruns that could return arbitrary data from
|
|
the program's dynamic memory area, where keys and other sensitive
|
|
information might be stored, OpenSSL supports the concept of a "secure heap."
|
|
The level and type of security guarantees depend on the operating system.
|
|
It is a good idea to review the code and see if it addresses your
|
|
threat model and concerns.
|
|
|
|
If a secure heap is used, then private key B<BIGNUM> values are stored there.
|
|
This protects long-term storage of private keys, but will not necessarily
|
|
put all intermediate values and computations there.
|
|
|
|
CRYPTO_secure_malloc_init() creates the secure heap, with the specified
|
|
C<size> in bytes. The C<minsize> parameter is the minimum size to
|
|
allocate from the heap. Both C<size> and C<minsize> must be a power
|
|
of two.
|
|
|
|
CRYPTO_secure_malloc_initialized() indicates whether or not the secure
|
|
heap as been initialized and is available.
|
|
|
|
CRYPTO_secure_malloc_done() releases the heap and makes the memory unavailable
|
|
to the process if all secure memory has been freed.
|
|
It can take noticeably long to complete.
|
|
|
|
OPENSSL_secure_malloc() allocates C<num> bytes from the heap.
|
|
If CRYPTO_secure_malloc_init() is not called, this is equivalent to
|
|
calling OPENSSL_malloc().
|
|
It is a macro that expands to
|
|
CRYPTO_secure_malloc() and adds the C<__FILE__> and C<__LINE__> parameters.
|
|
|
|
OPENSSL_secure_zalloc() and CRYPTO_secure_zalloc() are like
|
|
OPENSSL_secure_malloc() and CRYPTO_secure_malloc(), respectively,
|
|
except that they call memset() to zero the memory before returning.
|
|
|
|
OPENSSL_secure_free() releases the memory at C<ptr> back to the heap.
|
|
It must be called with a value previously obtained from
|
|
OPENSSL_secure_malloc().
|
|
If CRYPTO_secure_malloc_init() is not called, this is equivalent to
|
|
calling OPENSSL_free().
|
|
It exists for consistency with OPENSSL_secure_malloc() , and
|
|
is a macro that expands to CRYPTO_secure_free() and adds the C<__FILE__>
|
|
and C<__LINE__> parameters..
|
|
|
|
OPENSSL_secure_allocated() tells whether or not a pointer is within
|
|
the secure heap.
|
|
OPENSSL_secure_actual_size() tells the actual size allocated to the
|
|
pointer; implementations may allocate more space than initially
|
|
requested, in order to "round up" and reduce secure heap fragmentation.
|
|
|
|
CRYPTO_secure_used() returns the number of bytes allocated in the
|
|
secure heap.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
CRYPTO_secure_malloc_init() returns 0 on failure, 1 if successful,
|
|
and 2 if successful but the heap could not be protected by memory
|
|
mapping.
|
|
|
|
CRYPTO_secure_malloc_initialized() returns 1 if the secure heap is
|
|
available (that is, if CRYPTO_secure_malloc_init() has been called,
|
|
but CRYPTO_secure_malloc_done() has not been called or failed) or 0 if not.
|
|
|
|
OPENSSL_secure_malloc() and OPENSSL_secure_zalloc() return a pointer into
|
|
the secure heap of the requested size, or C<NULL> if memory could not be
|
|
allocated.
|
|
|
|
CRYPTO_secure_allocated() returns 1 if the pointer is in the secure heap, or 0 if not.
|
|
|
|
CRYPTO_secure_malloc_done() returns 1 if the secure memory area is released, or 0 if not.
|
|
|
|
OPENSSL_secure_free() returns no values.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<OPENSSL_malloc(3)>,
|
|
L<BN_new(3)>
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
|
|
|
|
Licensed under the OpenSSL license (the "License"). You may not use
|
|
this file except in compliance with the License. You can obtain a copy
|
|
in the file LICENSE in the source distribution or at
|
|
L<https://www.openssl.org/source/license.html>.
|
|
|
|
=cut
|