Add zstd compression

Author: phaag

compress.go

@@ -12,6 +12,7 @@ import (
 	"fmt"
 	"io"
 
+	zstd "github.com/klauspost/compress/zstd"
 	"github.com/pierrec/lz4/v4"
 	lzo "github.com/rasky/go-lzo"
 )
@@ -51,6 +52,14 @@ func (nfFile *NfFile) uncompressBlock(blockHeader *DataBlockHeader) ([]byte, err
 		out = out[:n]
 		dataBlock = out
 		blockHeader.Size = uint32(n)
+	case ZSTD_COMPRESSED:
+		var decoder, _ = zstd.NewReader(nil, zstd.WithDecoderConcurrency(0))
+		out, err := decoder.DecodeAll(dataBlock, nil)
+		if err != nil {
+			return nil, fmt.Errorf("nfFile uncompress zstd data block: %v", err)
+		}
+		dataBlock = out
+		blockHeader.Size = uint32(len(out))
 	default:
 		return nil, fmt.Errorf("unknown data block compression: %d", nfFile.Header.Compression)
 	}

go.mod

@@ -1,8 +1,9 @@
 module github.com/phaag/go-nfdump
 
-go 1.17
+go 1.21
 
 require (
+	github.com/klauspost/compress v1.17.8
 	github.com/pierrec/lz4/v4 v4.1.17
 	github.com/rasky/go-lzo v0.0.0-20200203143853-96a758eda86e
 )

go.sum

@@ -1,3 +1,5 @@
+github.com/klauspost/compress v1.17.8 h1:YcnTYrq7MikUT7k0Yb5eceMmALQPYBW/Xltxn0NAMnU=
+github.com/klauspost/compress v1.17.8/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
 github.com/pierrec/lz4/v4 v4.1.17 h1:kV4Ip+/hUBC+8T6+2EgburRtkE9ef4nbY3f4dFhGjMc=
 github.com/pierrec/lz4/v4 v4.1.17/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
 github.com/rasky/go-lzo v0.0.0-20200203143853-96a758eda86e h1:dCWirM5F3wMY+cmRda/B1BiPsFtmzXqV9b0hLWtVBMs=

nffile.go

@@ -27,6 +27,7 @@ const NOT_COMPRESSED = 0
 const LZO_COMPRESSED = 1
 const BZ2_COMPRESSED = 2
 const LZ4_COMPRESSED = 3
+const ZSTD_COMPRESSED = 4
 
 const BUFFSIZE = 5 * 1048576
 
@@ -40,6 +41,7 @@ type NfFileHeader struct {
 	// LZO_COMPRESSED 1
 	// BZ2_COMPRESSED 2
 	// LZ4_COMPRESSED 3
+	// ZSTD_COMPRESSED 4
 	Encryption uint8 // type of encryption
 	// NOT_ENCRYPTED 0
 	AppendixBlocks uint16 // number of blocks to read from appendix