gstreamer/gst/pcapparse/gstpcapparse.c

479 lines
12 KiB
C
Raw Normal View History

/*
* Copyright 2007 Ole André Vadla Ravnås <ole.andre.ravnas@tandberg.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-pcapparse
*
* Extracts payloads from Ethernet-encapsulated IP packets, currently limited
* to UDP. Use #GstPcapParse:src-ip, #GstPcapParse:dst-ip,
* #GstPcapParse:src-port and #GstPcapParse:dst-port to restrict which packets
* should be included.
*
* <refsect2>
* <title>Example pipelines</title>
* |[
* gst-launch-0.10 filesrc location=h264crasher.pcap ! pcapparse ! rtph264depay
* ! ffdec_h264 ! fakesink
* ]| Read from a pcap dump file using filesrc, extract the raw UDP packets,
* depayload and decode them.
* </refsect2>
*/
/* TODO:
* - React on state-change and update state accordingly.
* - Implement support for timestamping the buffers.
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "gstpcapparse.h"
#include <string.h>
#ifndef G_OS_WIN32
#include <arpa/inet.h>
#include <netinet/in.h>
#include <string.h>
#else
#include <winsock2.h>
#endif
enum
{
PROP_0,
PROP_SRC_IP,
PROP_DST_IP,
PROP_SRC_PORT,
PROP_DST_PORT,
};
GST_DEBUG_CATEGORY_STATIC (gst_pcap_parse_debug);
#define GST_CAT_DEFAULT gst_pcap_parse_debug
static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("raw/x-pcap"));
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
static void gst_pcap_parse_dispose (GObject * object);
static void gst_pcap_parse_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_pcap_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_pcap_parse_reset (GstPcapParse * self);
static GstFlowReturn gst_pcap_parse_chain (GstPad * pad, GstBuffer * buffer);
GST_BOILERPLATE (GstPcapParse, gst_pcap_parse, GstElement, GST_TYPE_ELEMENT);
static void
gst_pcap_parse_base_init (gpointer gclass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (gclass);
static GstElementDetails element_details = {
"PCapParse",
"Raw/Parser",
"Parses a raw pcap stream",
"Ole André Vadla Ravnås <ole.andre.ravnas@tandberg.com>"
};
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_template));
gst_element_class_set_details (element_class, &element_details);
}
static void
gst_pcap_parse_class_init (GstPcapParseClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->dispose = gst_pcap_parse_dispose;
gobject_class->get_property = gst_pcap_parse_get_property;
gobject_class->set_property = gst_pcap_parse_set_property;
g_object_class_install_property (gobject_class,
PROP_SRC_IP, g_param_spec_string ("src-ip", "Source IP",
"Source IP to restrict to", "", G_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_DST_IP, g_param_spec_string ("dst-ip", "Destination IP",
"Destination IP to restrict to", "", G_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_SRC_PORT, g_param_spec_int ("src-port", "Source port",
"Source port to restrict to", -1, G_MAXUINT16, -1,
G_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_DST_PORT, g_param_spec_int ("dst-port", "Destination port",
"Destination port to restrict to", -1, G_MAXUINT16, -1,
G_PARAM_READWRITE));
GST_DEBUG_CATEGORY_INIT (gst_pcap_parse_debug, "pcapparse", 0, "pcap parser");
}
static void
gst_pcap_parse_init (GstPcapParse * self, GstPcapParseClass * gclass)
{
self->sink_pad = gst_pad_new_from_static_template (&sink_template, "sink");
gst_pad_set_chain_function (self->sink_pad,
GST_DEBUG_FUNCPTR (gst_pcap_parse_chain));
gst_pad_use_fixed_caps (self->sink_pad);
gst_element_add_pad (GST_ELEMENT (self), self->sink_pad);
self->src_pad = gst_pad_new_from_static_template (&src_template, "src");
gst_pad_use_fixed_caps (self->src_pad);
gst_element_add_pad (GST_ELEMENT (self), self->src_pad);
self->src_ip = -1;
self->dst_ip = -1;
self->src_port = -1;
self->dst_port = -1;
self->adapter = gst_adapter_new ();
gst_pcap_parse_reset (self);
}
static void
gst_pcap_parse_dispose (GObject * object)
{
GstPcapParse *self = GST_PCAP_PARSE (object);
g_object_unref (self->adapter);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static const gchar *
get_ip_address_as_string (gint64 ip_addr)
{
if (ip_addr >= 0) {
struct in_addr addr;
addr.s_addr = ip_addr;
return inet_ntoa (addr);
} else {
return "";
}
}
static void
set_ip_address_from_string (gint64 * ip_addr, const gchar * ip_str)
{
if (ip_str[0] != '\0') {
gulong addr = inet_addr (ip_str);
if (addr != INADDR_NONE)
*ip_addr = addr;
} else {
*ip_addr = -1;
}
}
static void
gst_pcap_parse_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstPcapParse *self = GST_PCAP_PARSE (object);
switch (prop_id) {
case PROP_SRC_IP:
g_value_set_string (value, get_ip_address_as_string (self->src_ip));
break;
case PROP_DST_IP:
g_value_set_string (value, get_ip_address_as_string (self->dst_ip));
break;
case PROP_SRC_PORT:
g_value_set_int (value, self->src_port);
break;
case PROP_DST_PORT:
g_value_set_int (value, self->dst_port);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pcap_parse_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstPcapParse *self = GST_PCAP_PARSE (object);
switch (prop_id) {
case PROP_SRC_IP:
set_ip_address_from_string (&self->src_ip, g_value_get_string (value));
break;
case PROP_DST_IP:
set_ip_address_from_string (&self->dst_ip, g_value_get_string (value));
break;
case PROP_SRC_PORT:
self->src_port = g_value_get_int (value);
break;
case PROP_DST_PORT:
self->dst_port = g_value_get_int (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pcap_parse_reset (GstPcapParse * self)
{
self->initialized = FALSE;
self->swap_endian = FALSE;
self->cur_packet_size = -1;
self->buffer_offset = 0;
gst_adapter_clear (self->adapter);
}
static guint32
gst_pcap_parse_read_uint32 (GstPcapParse * self, const guint8 * p)
{
guint32 val = *((guint32 *) p);
if (self->swap_endian) {
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
return GUINT32_FROM_BE (val);
#else
return GUINT32_FROM_LE (val);
#endif
} else {
return val;
}
}
#define ETH_HEADER_LEN 14
#define IP_HEADER_MIN_LEN 20
#define UDP_HEADER_LEN 8
#define IP_PROTO_UDP 17
static gboolean
gst_pcap_parse_scan_frame (GstPcapParse * self,
const guint8 * buf,
gint buf_size, const guint8 ** payload, gint * payload_size)
{
const guint8 *buf_ip;
const guint8 *buf_udp;
guint16 eth_type;
guint8 b;
guint8 ip_header_size;
guint8 ip_protocol;
guint32 ip_src_addr;
guint32 ip_dst_addr;
guint16 udp_src_port;
guint16 udp_dst_port;
guint16 udp_len;
if (buf_size < ETH_HEADER_LEN + IP_HEADER_MIN_LEN + UDP_HEADER_LEN)
return FALSE;
eth_type = GUINT16_FROM_BE (*((guint16 *) (buf + 12)));
if (eth_type != 0x800)
return FALSE;
buf_ip = buf + ETH_HEADER_LEN;
b = *buf_ip;
if (((b >> 4) & 0x0f) != 4)
return FALSE;
ip_header_size = (b & 0x0f) * 4;
if (buf_ip + ip_header_size > buf + buf_size)
return FALSE;
ip_protocol = *(buf_ip + 9);
if (ip_protocol != IP_PROTO_UDP)
return FALSE;
ip_src_addr = *((guint32 *) (buf_ip + 12));
if (self->src_ip >= 0 && ip_src_addr != self->src_ip)
return FALSE;
ip_dst_addr = *((guint32 *) (buf_ip + 16));
if (self->dst_ip >= 0 && ip_dst_addr != self->dst_ip)
return FALSE;
buf_udp = buf_ip + ip_header_size;
udp_src_port = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 0)));
if (self->src_port >= 0 && udp_src_port != self->src_port)
return FALSE;
udp_dst_port = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 2)));
if (self->dst_port >= 0 && udp_dst_port != self->dst_port)
return FALSE;
udp_len = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 4)));
if (udp_len < UDP_HEADER_LEN || buf_udp + udp_len > buf + buf_size)
return FALSE;
*payload = buf_udp + UDP_HEADER_LEN;
*payload_size = udp_len - UDP_HEADER_LEN;
return TRUE;
}
static GstFlowReturn
gst_pcap_parse_chain (GstPad * pad, GstBuffer * buffer)
{
GstPcapParse *self = GST_PCAP_PARSE (GST_PAD_PARENT (pad));
GstFlowReturn ret = GST_FLOW_OK;
if (GST_PAD_CAPS (self->src_pad) == NULL) {
GstCaps *caps;
caps = gst_pad_peer_get_caps (self->src_pad);
if (caps == NULL)
return GST_FLOW_NOT_NEGOTIATED;
if (!gst_caps_is_fixed (caps) || !gst_pad_set_caps (self->src_pad, caps)) {
gst_caps_unref (caps);
return GST_FLOW_NOT_NEGOTIATED;
}
gst_caps_unref (caps);
}
gst_adapter_push (self->adapter, buffer);
while (ret == GST_FLOW_OK) {
gint avail;
const guint8 *data;
avail = gst_adapter_available (self->adapter);
if (self->initialized) {
if (self->cur_packet_size >= 0) {
if (avail < self->cur_packet_size)
break;
if (self->cur_packet_size > 0) {
const guint8 *payload_data;
gint payload_size;
data = gst_adapter_peek (self->adapter, self->cur_packet_size);
if (gst_pcap_parse_scan_frame (self, data, self->cur_packet_size,
&payload_data, &payload_size)) {
GstBuffer *out_buf;
ret = gst_pad_alloc_buffer_and_set_caps (self->src_pad,
self->buffer_offset, payload_size,
GST_PAD_CAPS (self->src_pad), &out_buf);
if (ret == GST_FLOW_OK) {
memcpy (GST_BUFFER_DATA (out_buf), payload_data, payload_size);
ret = gst_pad_push (self->src_pad, out_buf);
self->buffer_offset += payload_size;
}
}
gst_adapter_flush (self->adapter, self->cur_packet_size);
}
self->cur_packet_size = -1;
} else {
guint32 ts_sec;
guint32 ts_usec;
guint32 incl_len;
guint32 orig_len;
if (avail < 16)
break;
data = gst_adapter_peek (self->adapter, 16);
ts_sec = gst_pcap_parse_read_uint32 (self, data + 0);
ts_usec = gst_pcap_parse_read_uint32 (self, data + 4);
incl_len = gst_pcap_parse_read_uint32 (self, data + 8);
orig_len = gst_pcap_parse_read_uint32 (self, data + 12);
gst_adapter_flush (self->adapter, 16);
self->cur_packet_size = incl_len;
}
} else {
guint magic;
if (avail < 24)
break;
data = gst_adapter_peek (self->adapter, 24);
magic = *((guint32 *) data);
gst_adapter_flush (self->adapter, 24);
if (magic == 0xa1b2c3d4)
self->swap_endian = FALSE;
else if (magic == 0xd4c3b2a1)
self->swap_endian = TRUE;
else
ret = GST_FLOW_ERROR;
if (ret == GST_FLOW_OK)
self->initialized = TRUE;
}
}
if (ret != GST_FLOW_OK)
gst_pcap_parse_reset (self);
return ret;
}
static gboolean
plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "pcapparse",
GST_RANK_NONE, GST_TYPE_PCAP_PARSE);
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"pcapparse",
"Element parsing raw pcap streams",
plugin_init, VERSION, "LGPL", "GStreamer", "http://gstreamer.net/")