d060b7b379
In general, it's fine to pass %NULL to g_free().
However, consider:
char *
foo (void)
{
gs_free char *value = NULL;
value = g_strdup ("hi");
return g_steal_pointer (&value);
}
gs_free, gs_local_free(), and g_steal_pointer() are all inlinable.
Here the compiler can easily recognize that we always pass %NULL to
g_free(). But with the previous implementation, the compiler would
not omit the call to g_free().
Similar patterns happen all over the place:
gboolean
baz (void)
{
gs_free char *value = NULL;
if (!some_check ())
return FALSE;
value = get_value ();
if (!value)
return FALSE;
return TRUE;
}
in this example, g_free() is only required after setting @value to
non-NULL.
Note that this does increase the binary side a bit (4k for libnm, 8k
for NetworkManager, with "-O2").
152 lines
3.9 KiB
C
152 lines
3.9 KiB
C
/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
|
|
/* NetworkManager -- Network link manager
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the
|
|
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
|
|
* Boston, MA 02110-1301 USA.
|
|
*
|
|
* (C) Copyright 2018 Red Hat, Inc.
|
|
*/
|
|
|
|
#ifndef __NM_SECRET_UTILS_H__
|
|
#define __NM_SECRET_UTILS_H__
|
|
|
|
#include "nm-macros-internal.h"
|
|
|
|
/*****************************************************************************/
|
|
|
|
void nm_explicit_bzero (void *s, gsize n);
|
|
|
|
/*****************************************************************************/
|
|
|
|
char *nm_secret_strchomp (char *secret);
|
|
|
|
/*****************************************************************************/
|
|
|
|
static inline void
|
|
nm_free_secret (char *secret)
|
|
{
|
|
if (secret) {
|
|
nm_explicit_bzero (secret, strlen (secret));
|
|
g_free (secret);
|
|
}
|
|
}
|
|
|
|
NM_AUTO_DEFINE_FCN0 (char *, _nm_auto_free_secret, nm_free_secret)
|
|
/**
|
|
* nm_auto_free_secret:
|
|
*
|
|
* Call g_free() on a variable location when it goes out of scope.
|
|
* Also, previously, calls memset(loc, 0, strlen(loc)) to clear out
|
|
* the secret.
|
|
*/
|
|
#define nm_auto_free_secret nm_auto(_nm_auto_free_secret)
|
|
|
|
/*****************************************************************************/
|
|
|
|
GBytes *nm_secret_copy_to_gbytes (gconstpointer mem, gsize mem_len);
|
|
|
|
/*****************************************************************************/
|
|
|
|
/* NMSecretPtr is a pair of malloc'ed data pointer and the length of the
|
|
* data. The purpose is to use it in combination with nm_auto_clear_secret_ptr
|
|
* which ensures that the data pointer (with all len bytes) is cleared upon
|
|
* cleanup. */
|
|
typedef struct {
|
|
gsize len;
|
|
|
|
/* the data pointer. This pointer must be allocated with malloc (at least
|
|
* when used with nm_secret_ptr_clear()). */
|
|
union {
|
|
char *str;
|
|
void *ptr;
|
|
guint8 *bin;
|
|
};
|
|
} NMSecretPtr;
|
|
|
|
static inline void
|
|
nm_secret_ptr_clear (NMSecretPtr *secret)
|
|
{
|
|
if (secret) {
|
|
if (secret->len > 0) {
|
|
if (secret->ptr)
|
|
nm_explicit_bzero (secret->ptr, secret->len);
|
|
secret->len = 0;
|
|
}
|
|
nm_clear_g_free (&secret->ptr);
|
|
}
|
|
}
|
|
|
|
#define nm_auto_clear_secret_ptr nm_auto(nm_secret_ptr_clear)
|
|
|
|
#define NM_SECRET_PTR_STATIC(_len) \
|
|
((const NMSecretPtr) { \
|
|
.len = _len, \
|
|
.ptr = ((guint8 [_len]) { }), \
|
|
})
|
|
|
|
static inline void
|
|
nm_secret_ptr_clear_static (const NMSecretPtr *secret)
|
|
{
|
|
if (secret) {
|
|
if (secret->len > 0) {
|
|
nm_assert (secret->ptr);
|
|
nm_explicit_bzero (secret->ptr, secret->len);
|
|
}
|
|
}
|
|
}
|
|
|
|
#define nm_auto_clear_static_secret_ptr nm_auto(nm_secret_ptr_clear_static)
|
|
|
|
static inline void
|
|
nm_secret_ptr_move (NMSecretPtr *dst, NMSecretPtr *src)
|
|
{
|
|
if (dst && dst != src) {
|
|
*dst = *src;
|
|
src->len = 0;
|
|
src->ptr = NULL;
|
|
}
|
|
}
|
|
|
|
/*****************************************************************************/
|
|
|
|
typedef struct {
|
|
const gsize len;
|
|
union {
|
|
char str[0];
|
|
guint8 bin[0];
|
|
};
|
|
} NMSecretBuf;
|
|
|
|
static inline void
|
|
_nm_auto_free_secret_buf (NMSecretBuf **ptr)
|
|
{
|
|
NMSecretBuf *b = *ptr;
|
|
|
|
if (b) {
|
|
nm_assert (b->len > 0);
|
|
nm_explicit_bzero (b->bin, b->len);
|
|
g_free (b);
|
|
}
|
|
}
|
|
#define nm_auto_free_secret_buf nm_auto(_nm_auto_free_secret_buf)
|
|
|
|
NMSecretBuf *nm_secret_buf_new (gsize len);
|
|
|
|
GBytes *nm_secret_buf_to_gbytes_take (NMSecretBuf *secret, gssize actual_len);
|
|
|
|
/*****************************************************************************/
|
|
|
|
#endif /* __NM_SECRET_UTILS_H__ */
|