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PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 52 insertions, 0 deletions

diff --git a/pkg/tcpip/link/sniffer/pcap.go b/pkg/tcpip/link/sniffer/pcap.go
new file mode 100644
index 000000000..6d0dd565a
--- /dev/null
+++ b/pkg/tcpip/link/sniffer/pcap.go
@@ -0,0 +1,52 @@
+package sniffer
+
+import "time"
+
+type pcapHeader struct {
+	// MagicNumber is the file magic number.
+	MagicNumber uint32
+
+	// VersionMajor is the major version number.
+	VersionMajor uint16
+
+	// VersionMinor is the minor version number.
+	VersionMinor uint16
+
+	// Thiszone is the GMT to local correction.
+	Thiszone int32
+
+	// Sigfigs is the accuracy of timestamps.
+	Sigfigs uint32
+
+	// Snaplen is the max length of captured packets, in octets.
+	Snaplen uint32
+
+	// Network is the data link type.
+	Network uint32
+}
+
+const pcapPacketHeaderLen = 16
+
+type pcapPacketHeader struct {
+	// Seconds is the timestamp seconds.
+	Seconds uint32
+
+	// Microseconds is the timestamp microseconds.
+	Microseconds uint32
+
+	// IncludedLength is the number of octets of packet saved in file.
+	IncludedLength uint32
+
+	// OriginalLength is the actual length of packet.
+	OriginalLength uint32
+}
+
+func newPCAPPacketHeader(incLen, orgLen uint32) pcapPacketHeader {
+	now := time.Now()
+	return pcapPacketHeader{
+		Seconds:        uint32(now.Unix()),
+		Microseconds:   uint32(now.Nanosecond() / 1000),
+		IncludedLength: incLen,
+		OriginalLength: orgLen,
+	}
+}