Commit 93af6831 authored by Mark Nauwelaerts's avatar Mark Nauwelaerts
Browse files

pcapparse: also support extracting tcp data

parent 04f0b556
......@@ -20,8 +20,8 @@
/**
* SECTION:element-pcapparse
*
* Extracts payloads from Ethernet-encapsulated IP packets, currently limited
* to UDP. Use #GstPcapParse:src-ip, #GstPcapParse:dst-ip,
* Extracts payloads from Ethernet-encapsulated IP packets.
* Use #GstPcapParse:src-ip, #GstPcapParse:dst-ip,
* #GstPcapParse:src-port and #GstPcapParse:dst-port to restrict which packets
* should be included.
*
......@@ -324,6 +324,8 @@ gst_pcap_parse_read_uint32 (GstPcapParse * self, const guint8 * p)
#define UDP_HEADER_LEN 8
#define IP_PROTO_UDP 17
#define IP_PROTO_TCP 6
static gboolean
gst_pcap_parse_scan_frame (GstPcapParse * self,
......@@ -331,16 +333,16 @@ gst_pcap_parse_scan_frame (GstPcapParse * self,
gint buf_size, const guint8 ** payload, gint * payload_size)
{
const guint8 *buf_ip = 0;
const guint8 *buf_udp;
const guint8 *buf_proto;
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;
guint16 src_port;
guint16 dst_port;
guint16 len;
switch (self->linktype) {
case DLT_ETHER:
......@@ -375,33 +377,52 @@ gst_pcap_parse_scan_frame (GstPcapParse * self,
return FALSE;
ip_protocol = *(buf_ip + 9);
if (ip_protocol != IP_PROTO_UDP)
return FALSE;
GST_LOG_OBJECT (self, "ip proto %d", (gint) ip_protocol);
ip_src_addr = *((guint32 *) (buf_ip + 12));
if (self->src_ip >= 0 && ip_src_addr != self->src_ip)
if (ip_protocol != IP_PROTO_UDP && ip_protocol != IP_PROTO_TCP)
return FALSE;
/* ip info */
ip_src_addr = *((guint32 *) (buf_ip + 12));
ip_dst_addr = *((guint32 *) (buf_ip + 16));
if (self->dst_ip >= 0 && ip_dst_addr != self->dst_ip)
return FALSE;
buf_proto = buf_ip + ip_header_size;
buf_udp = buf_ip + ip_header_size;
/* ok for tcp and udp */
src_port = GUINT16_FROM_BE (*((guint16 *) (buf_proto + 0)));
dst_port = GUINT16_FROM_BE (*((guint16 *) (buf_proto + 2)));
udp_src_port = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 0)));
if (self->src_port >= 0 && udp_src_port != self->src_port)
/* extract some params and data according to protocol */
if (ip_protocol == IP_PROTO_UDP) {
len = GUINT16_FROM_BE (*((guint16 *) (buf_proto + 4)));
if (len < UDP_HEADER_LEN || buf_proto + len > buf + buf_size)
return FALSE;
*payload = buf_proto + UDP_HEADER_LEN;
*payload_size = len - UDP_HEADER_LEN;
} else {
if (buf_proto + 12 >= buf + buf_size)
return FALSE;
len = (buf_proto[12] >> 4) * 4;
if (buf_proto + len > buf + buf_size)
return FALSE;
/* all remaining data following tcp header is payload */
*payload = buf_proto + len;
*payload_size = self->cur_packet_size - (buf_proto - buf) - len;
}
/* but still filter as configured */
if (self->src_ip >= 0 && ip_src_addr != self->src_ip)
return FALSE;
udp_dst_port = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 2)));
if (self->dst_port >= 0 && udp_dst_port != self->dst_port)
if (self->dst_ip >= 0 && ip_dst_addr != self->dst_ip)
return FALSE;
udp_len = GUINT16_FROM_BE (*((guint16 *) (buf_udp + 4)));
if (udp_len < UDP_HEADER_LEN || buf_udp + udp_len > buf + buf_size)
if (self->src_port >= 0 && src_port != self->src_port)
return FALSE;
*payload = buf_udp + UDP_HEADER_LEN;
*payload_size = udp_len - UDP_HEADER_LEN;
if (self->dst_port >= 0 && dst_port != self->dst_port)
return FALSE;
return TRUE;
}
......
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