// SPDX-License-Identifier: LGPL-2.1-or-later
/*
* dvb_demux.c - DVB kernel demux API
*
* Copyright (C) 2000-2001 Ralph Metzler <ralph@convergence.de>
* & Marcus Metzler <marcus@convergence.de>
* for convergence integrated media GmbH
*/
#define pr_fmt(fmt) "dvb_demux: " fmt
#include <linux/sched/signal.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/string.h>
#include <linux/crc32.h>
#include <linux/uaccess.h>
#include <asm/div64.h>
#include <media/dvb_demux.h>
static int dvb_demux_tscheck;
module_param(dvb_demux_tscheck, int, 0644);
MODULE_PARM_DESC(dvb_demux_tscheck,
"enable transport stream continuity and TEI check");
static int dvb_demux_speedcheck;
module_param(dvb_demux_speedcheck, int, 0644);
MODULE_PARM_DESC(dvb_demux_speedcheck,
"enable transport stream speed check");
static int dvb_demux_feed_err_pkts = 1;
module_param(dvb_demux_feed_err_pkts, int, 0644);
MODULE_PARM_DESC(dvb_demux_feed_err_pkts,
"when set to 0, drop packets with the TEI bit set (1 by default)");
#define dprintk(fmt, arg...) \
printk(KERN_DEBUG pr_fmt("%s: " fmt), __func__, ##arg)
#define dprintk_tscheck(x...) do { \
if (dvb_demux_tscheck && printk_ratelimit()) \
dprintk(x); \
} while (0)
#ifdef CONFIG_DVB_DEMUX_SECTION_LOSS_LOG
# define dprintk_sect_loss(x...) dprintk(x)
#else
# define dprintk_sect_loss(x...)
#endif
#define set_buf_flags(__feed, __flag) \
do { \
(__feed)->buffer_flags |= (__flag); \
} while (0)
/******************************************************************************
* static inlined helper functions
******************************************************************************/
static inline u16 section_length(const u8 *buf)
{
return 3 + ((buf[1] & 0x0f) << 8) + buf[2];
}
static inline u16 ts_pid(const u8 *buf)
{
return ((buf[1] & 0x1f) << 8) + buf[2];
}
static inline u8 payload(const u8 *tsp)
{
if (!(tsp[3] & 0x10)) // no payload?
return 0;
if (tsp[3] & 0x20) { // adaptation field?
if (tsp[4] > 183) // corrupted data?
return 0;
else
return 184 - 1 - tsp[4];
}
return 184;
}
static u32 dvb_dmx_crc32(struct dvb_demux_feed *f, const u8 *src, size_t len)
{
return (f->feed.sec.crc_val = crc32_be(f->feed.sec.crc_val, src, len));
}
static void dvb_dmx_memcopy(struct dvb_demux_feed *f, u8 *d, const u8 *s,
size_t len)
{
memcpy(d, s, len);
}
/******************************************************************************
* Software filter functions
******************************************************************************/
static inline int dvb_dmx_swfilter_payload(struct dvb_demux_feed *feed,
const u8 *buf)
{
int count = payload(buf);
int p;
int ccok;
u8 cc;
if (count