/*
* Amanda, The Advanced Maryland Automatic Network Disk Archiver
* Copyright (c) 2008-2012 Zmanda, Inc. All Rights Reserved.
* Copyright (c) 2013-2016 Carbonite, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Contact information: Carbonite Inc., 756 N Pastoria Ave
* Sunnyvale, CA 94085, or: http://www.zmanda.com
*/
#include "amanda.h"
#include "amxfer.h"
/*
* Class declaration
*
* This declaration is entirely private; nothing but xfer_filter_xor() references
* it directly.
*/
GType xfer_filter_xor_get_type(void);
#define XFER_FILTER_XOR_TYPE (xfer_filter_xor_get_type())
#define XFER_FILTER_XOR(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_filter_xor_get_type(), XferFilterXor)
#define XFER_FILTER_XOR_CONST(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_filter_xor_get_type(), XferFilterXor const)
#define XFER_FILTER_XOR_CLASS(klass) G_TYPE_CHECK_CLASS_CAST((klass), xfer_filter_xor_get_type(), XferFilterXorClass)
#define IS_XFER_FILTER_XOR(obj) G_TYPE_CHECK_INSTANCE_TYPE((obj), xfer_filter_xor_get_type ())
#define XFER_FILTER_XOR_GET_CLASS(obj) G_TYPE_INSTANCE_GET_CLASS((obj), xfer_filter_xor_get_type(), XferFilterXorClass)
static GObjectClass *parent_class = NULL;
/*
* Main object structure
*/
typedef struct XferFilterXor {
XferElement __parent__;
char xor_key;
} XferFilterXor;
/*
* Class definition
*/
typedef struct {
XferElementClass __parent__;
} XferFilterXorClass;
/*
* Utilities
*/
static void
apply_xor(
char *buf,
size_t len,
char xor_key)
{
size_t i;
/* Apply XOR. This is a pretty sophisticated encryption algorithm! */
for (i = 0; i < len; i++) {
buf[i] ^= xor_key;
}
}
/*
* Implementation
*/
static gpointer
pull_buffer_impl(
XferElement *elt,
size_t *size)
{
XferFilterXor *self = (XferFilterXor *)elt;
char *buf;
if (elt->cancelled) {
/* drain our upstream only if we're expecting an EOF */
if (elt->expect_eof) {
xfer_element_drain_buffers(XFER_ELEMENT(self)->upstream);
}
/* return an EOF */
*size = 0;
return NULL;
}
/* get a buffer from upstream, xor it, and hand it back */
buf = xfer_element_pull_buffer(XFER_ELEMENT(self)->upstream, size);
if (buf)
apply_xor(buf, *size, self->xor_key);
return buf;
}
static gpointer
pull_buffer_static_impl(
XferElement *elt,
gpointer buf,
size_t block_size,
size_t *size)
{
XferFilterXor *self = (XferFilterXor *)elt;
if (elt->cancelled) {
/* drain our upstream only if we're expecting an EOF */
if (elt->expect_eof) {
xfer_element_drain_buffers(XFER_ELEMENT(self)->upstream);
}
/* return an EOF */
*size = 0;
return NULL;
}
/* get a buffer from upstream, xor it, and hand it back */
xfer_element_pull_buffer_static(XFER_ELEMENT(self)->upstream, buf, block_size, size);
if (*size)
apply_xor(buf, *size, self->xor_key);
return buf;
}
static void
push_buffer_impl(
XferElement *elt,
gpointer buf,
size_t len)
{
XferFilterXor *self = (XferFilterXor *)elt;
/* drop the buffer if we've been cancelled */
if (elt->cancelled) {
amfree(buf);
return;
}
/* xor the given buffer and pass it downstream */
if (buf)
apply_xor(buf, len, self->xor_key);
xfer_element_push_buffer(XFER_ELEMENT(self)->downstream, buf, len);
}
static void
push_buffer_static_impl(
XferElement *elt,
gpointer buf,
size_t len)
{
XferFilterXor *self = (XferFilterXor *)elt;
/* drop the buffer if we've been cancelled */
if (elt->cancelled) {
amfree(buf);
return;
}
/* xor the given buffer and pass it downstream */
if (buf && len != 0)
apply_xor(buf, len, self->xor_key);
xfer_element_push_buffer_static(XFER_ELEMENT(self)->downstream, buf, len);
}
static void
instance_init(
XferElement *elt)
{
elt->can_generate_eof = TRUE;
}
static void
class_init(
XferFilterXorClass * selfc)
{
XferElementClass *klass = XFER_ELEMENT_CLASS(selfc);
static xfer_element_mech_pair_t mech_pairs[] = {
{ XFER_MECH_PULL_BUFFER, XFER_MECH_PULL_BUFFER, XFER_NROPS(1), XFER_NTHREADS(0), XFER_NALLOC(0) },
{ XFER_MECH_PUSH_BUFFER, XFER_MECH_PUSH_BUFFER, XFER_NROPS(1), XFER_NTHREADS(0), XFER_NALLOC(0) },
{ XFER_MECH_PULL_BUFFER_STATIC, XFER_MECH_PULL_BUFFER_STATIC, XFER_NROPS(1), XFER_NTHREADS(0), XFER_NALLOC(0) },
{ XFER_MECH_PUSH_BUFFER_STATIC, XFER_MECH_PUSH_BUFFER_STATIC, XFER_NROPS(1), XFER_NTHREADS(0), XFER_NALLOC(0) },
{ XFER_MECH_NONE, XFER_MECH_NONE, XFER_NROPS(0), XFER_NTHREADS(0), XFER_NALLOC(0) },
};
klass->push_buffer = push_buffer_impl;
klass->push_buffer_static = push_buffer_static_impl;
klass->pull_buffer = pull_buffer_impl;
klass->pull_buffer_static = pull_buffer_static_impl;
klass->perl_class = "Amanda::Xfer::Filter::Xor";
klass->mech_pairs = mech_pairs;
parent_class = g_type_class_peek_parent(selfc);
}
GType
xfer_filter_xor_get_type (void)
{
static GType type = 0;
if (G_UNLIKELY(type == 0)) {
static const GTypeInfo info = {
sizeof (XferFilterXorClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) class_init,
(GClassFinalizeFunc) NULL,
NULL /* class_data */,
sizeof (XferFilterXor),
0 /* n_preallocs */,
(GInstanceInitFunc) instance_init,
NULL
};
type = g_type_register_static (XFER_ELEMENT_TYPE, "XferFilterXor", &info, 0);
}
return type;
}
/* create an element of this class; prototype is in xfer-element.h */
XferElement *
xfer_filter_xor(
unsigned char xor_key)
{
XferFilterXor *xfx = (XferFilterXor *)g_object_new(XFER_FILTER_XOR_TYPE, NULL);
XferElement *elt = XFER_ELEMENT(xfx);
xfx->xor_key = xor_key;
return elt;
}