BadVPN – Rev 1
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/**
* @file RouteBuffer.c
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <misc/offset.h>
#include <flow/RouteBuffer.h>
static struct RouteBuffer_packet * alloc_packet (int mtu)
{
if (mtu > SIZE_MAX - sizeof(struct RouteBuffer_packet)) {
return NULL;
}
// allocate memory
struct RouteBuffer_packet *p = (struct RouteBuffer_packet *)malloc(sizeof(*p) + mtu);
if (!p) {
return NULL;
}
return p;
}
static int alloc_free_packet (RouteBuffer *o)
{
struct RouteBuffer_packet *p = alloc_packet(o->mtu);
if (!p) {
return 0;
}
// add to free packets list
LinkedList1_Append(&o->packets_free, &p->node);
return 1;
}
static void free_free_packets (RouteBuffer *o)
{
while (!LinkedList1_IsEmpty(&o->packets_free)) {
// get packet
struct RouteBuffer_packet *p = UPPER_OBJECT(LinkedList1_GetLast(&o->packets_free), struct RouteBuffer_packet, node);
// remove from free packets list
LinkedList1_Remove(&o->packets_free, &p->node);
// free memory
free(p);
}
}
static void release_used_packet (RouteBuffer *o)
{
ASSERT(!LinkedList1_IsEmpty(&o->packets_used))
// get packet
struct RouteBuffer_packet *p = UPPER_OBJECT(LinkedList1_GetFirst(&o->packets_used), struct RouteBuffer_packet, node);
// remove from used packets list
LinkedList1_Remove(&o->packets_used, &p->node);
// add to free packets list
LinkedList1_Append(&o->packets_free, &p->node);
}
static void send_used_packet (RouteBuffer *o)
{
ASSERT(!LinkedList1_IsEmpty(&o->packets_used))
// get packet
struct RouteBuffer_packet *p = UPPER_OBJECT(LinkedList1_GetFirst(&o->packets_used), struct RouteBuffer_packet, node);
// send
PacketPassInterface_Sender_Send(o->output, (uint8_t *)(p + 1), p->len);
}
static void output_handler_done (RouteBuffer *o)
{
ASSERT(!LinkedList1_IsEmpty(&o->packets_used))
DebugObject_Access(&o->d_obj);
// release packet
release_used_packet(o);
// send next packet if there is one
if (!LinkedList1_IsEmpty(&o->packets_used)) {
send_used_packet(o);
}
}
int RouteBuffer_Init (RouteBuffer *o, int mtu, PacketPassInterface *output, int buf_size)
{
ASSERT(mtu >= 0)
ASSERT(PacketPassInterface_GetMTU(output) >= mtu)
ASSERT(buf_size > 0)
// init arguments
o->mtu = mtu;
o->output = output;
// init output
PacketPassInterface_Sender_Init(o->output, (PacketPassInterface_handler_done)output_handler_done, o);
// init free packets list
LinkedList1_Init(&o->packets_free);
// init used packets list
LinkedList1_Init(&o->packets_used);
// allocate packets
for (int i = 0; i < buf_size; i++) {
if (!alloc_free_packet(o)) {
goto fail1;
}
}
DebugObject_Init(&o->d_obj);
return 1;
fail1:
free_free_packets(o);
return 0;
}
void RouteBuffer_Free (RouteBuffer *o)
{
DebugObject_Free(&o->d_obj);
// release packets so they can be freed
while (!LinkedList1_IsEmpty(&o->packets_used)) {
release_used_packet(o);
}
// free packets
free_free_packets(o);
}
int RouteBuffer_GetMTU (RouteBuffer *o)
{
DebugObject_Access(&o->d_obj);
return o->mtu;
}
int RouteBufferSource_Init (RouteBufferSource *o, int mtu)
{
ASSERT(mtu >= 0)
// init arguments
o->mtu = mtu;
// allocate current packet
if (!(o->current_packet = alloc_packet(o->mtu))) {
goto fail0;
}
DebugObject_Init(&o->d_obj);
return 1;
fail0:
return 0;
}
void RouteBufferSource_Free (RouteBufferSource *o)
{
DebugObject_Free(&o->d_obj);
// free current packet
free(o->current_packet);
}
uint8_t * RouteBufferSource_Pointer (RouteBufferSource *o)
{
DebugObject_Access(&o->d_obj);
return (uint8_t *)(o->current_packet + 1);
}
int RouteBufferSource_Route (RouteBufferSource *o, int len, RouteBuffer *b, int copy_offset, int copy_len)
{
ASSERT(len >= 0)
ASSERT(len <= o->mtu)
ASSERT(b->mtu == o->mtu)
ASSERT(copy_offset >= 0)
ASSERT(copy_offset <= o->mtu)
ASSERT(copy_len >= 0)
ASSERT(copy_len <= o->mtu - copy_offset)
DebugObject_Access(&b->d_obj);
DebugObject_Access(&o->d_obj);
// check if there's space in the buffer
if (LinkedList1_IsEmpty(&b->packets_free)) {
return 0;
}
int was_empty = LinkedList1_IsEmpty(&b->packets_used);
struct RouteBuffer_packet *p = o->current_packet;
// set packet length
p->len = len;
// append packet to used packets list
LinkedList1_Append(&b->packets_used, &p->node);
// get a free packet
struct RouteBuffer_packet *np = UPPER_OBJECT(LinkedList1_GetLast(&b->packets_free), struct RouteBuffer_packet, node);
// remove it from free packets list
LinkedList1_Remove(&b->packets_free, &np->node);
// make it the current packet
o->current_packet = np;
// copy packet
if (copy_len > 0) {
memcpy((uint8_t *)(np + 1) + copy_offset, (uint8_t *)(p + 1) + copy_offset, copy_len);
}
// start sending if required
if (was_empty) {
send_used_packet(b);
}
return 1;
}