Commit ba8376b5 authored by Bernd Edlinger's avatar Bernd Edlinger
Browse files

Implement the CRYPTO_secure_clear_free function. 


Use OPENSSL_secure_clear_free for secure mem BIOs
and X25519 private keys.

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4048)
parent a2ce0814

crypto/buffer/buffer.c

+2 −2
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ void BUF_MEM_free(BUF_MEM *a) 


    if (a->data != NULL) {

        if (a->flags & BUF_MEM_FLAG_SECURE)

            OPENSSL_secure_free(a->data);

            OPENSSL_secure_clear_free(a->data, a->max);

        else

            OPENSSL_clear_free(a->data, a->max);

    }
@@ -64,7 +64,7 @@ static char *sec_alloc_realloc(BUF_MEM *str, size_t len) 
    if (str->data != NULL) {

        if (ret != NULL) {

            memcpy(ret, str->data, str->length);

            OPENSSL_secure_free(str->data);

            OPENSSL_secure_clear_free(str->data, str->length);

            str->data = NULL;

        }

    }

crypto/ec/ecx_meth.c

+1 −1
Original line number Diff line number Diff line
@@ -212,7 +212,7 @@ static void ecx_free(EVP_PKEY *pkey) 
    X25519_KEY *xkey = pkey->pkey.ptr;



    if (xkey)

        OPENSSL_secure_free(xkey->privkey);

        OPENSSL_secure_clear_free(xkey->privkey, X25519_KEYLEN);

    OPENSSL_free(xkey);

}

crypto/mem_sec.c

+27 −0
Original line number Diff line number Diff line
@@ -156,6 +156,33 @@ void CRYPTO_secure_free(void *ptr, const char *file, int line) 
#endif /* IMPLEMENTED */

}



void CRYPTO_secure_clear_free(void *ptr, size_t num,

                              const char *file, int line)

{

#ifdef IMPLEMENTED

    size_t actual_size;



    if (ptr == NULL)

        return;

    if (!CRYPTO_secure_allocated(ptr)) {

        OPENSSL_cleanse(ptr, num);

        CRYPTO_free(ptr, file, line);

        return;

    }

    CRYPTO_THREAD_write_lock(sec_malloc_lock);

    actual_size = sh_actual_size(ptr);

    CLEAR(ptr, actual_size);

    secure_mem_used -= actual_size;

    sh_free(ptr);

    CRYPTO_THREAD_unlock(sec_malloc_lock);

#else

    if (ptr == NULL)

        return;

    OPENSSL_cleanse(ptr, num);

    CRYPTO_free(ptr, file, line);

#endif /* IMPLEMENTED */

}



int CRYPTO_secure_allocated(const void *ptr)

{

#ifdef IMPLEMENTED

doc/crypto/OPENSSL_secure_malloc.pod

+8 −1
Original line number Diff line number Diff line
@@ -27,6 +27,9 @@ CRYPTO_secure_used - secure heap storage 
 void OPENSSL_secure_free(void* ptr);

 void CRYPTO_secure_free(void *ptr, const char *, int);



 void OPENSSL_secure_clear_free(void* ptr, size_t num);

 void CRYPTO_secure_clear_free(void *ptr, size_t num, const char *, int);



 size_t OPENSSL_secure_actual_size(const void *ptr);

 int OPENSSL_secure_allocated(const void *ptr);
@@ -104,13 +107,17 @@ CRYPTO_secure_allocated() returns 1 if the pointer is in the secure heap, or 0 i 


CRYPTO_secure_malloc_done() returns 1 if the secure memory area is released, or 0 if not.



OPENSSL_secure_free() returns no values.

OPENSSL_secure_free() and OPENSSL_secure_clear_free() return no values.



=head1 SEE ALSO



L<OPENSSL_malloc(3)>,

L<BN_new(3)>



=head1 HISTORY



OPENSSL_secure_clear_free() was added in OpenSSL 1.1.0g.



=head1 COPYRIGHT



Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.

include/openssl/crypto.h

+4 −0
Original line number Diff line number Diff line
@@ -146,6 +146,8 @@ int CRYPTO_mem_ctrl(int mode); 
        CRYPTO_secure_zalloc(num, OPENSSL_FILE, OPENSSL_LINE)

# define OPENSSL_secure_free(addr) \

        CRYPTO_secure_free(addr, OPENSSL_FILE, OPENSSL_LINE)

# define OPENSSL_secure_clear_free(addr, num) \

        CRYPTO_secure_clear_free(addr, num, OPENSSL_FILE, OPENSSL_LINE)

# define OPENSSL_secure_actual_size(ptr) \

        CRYPTO_secure_actual_size(ptr)
@@ -285,6 +287,8 @@ int CRYPTO_secure_malloc_done(void); 
void *CRYPTO_secure_malloc(size_t num, const char *file, int line);

void *CRYPTO_secure_zalloc(size_t num, const char *file, int line);

void CRYPTO_secure_free(void *ptr, const char *file, int line);

void CRYPTO_secure_clear_free(void *ptr, size_t num,

                              const char *file, int line);

int CRYPTO_secure_allocated(const void *ptr);

int CRYPTO_secure_malloc_initialized(void);

size_t CRYPTO_secure_actual_size(void *ptr);