1 files changed, 117 insertions, 0 deletions
diff --git a/scripts/external_libs/dpkt-1.8.6/dpkt/gzip.py b/scripts/external_libs/dpkt-1.8.6/dpkt/gzip.py
new file mode 100644
index 00000000..e0bc619f
--- /dev/null
+++ b/scripts/external_libs/dpkt-1.8.6/dpkt/gzip.py
@@ -0,0 +1,117 @@
+# $Id: gzip.py 23 2006-11-08 15:45:33Z dugsong $
+
+"""GNU zip."""
+
+import struct, zlib
+import dpkt
+
+# RFC 1952
+GZIP_MAGIC	= '\x1f\x8b'
+
+# Compression methods
+GZIP_MSTORED	= 0
+GZIP_MCOMPRESS	= 1
+GZIP_MPACKED	= 2
+GZIP_MLZHED	= 3
+GZIP_MDEFLATE	= 8
+
+# Flags
+GZIP_FTEXT	= 0x01
+GZIP_FHCRC	= 0x02
+GZIP_FEXTRA	= 0x04
+GZIP_FNAME	= 0x08
+GZIP_FCOMMENT	= 0x10
+GZIP_FENCRYPT	= 0x20
+GZIP_FRESERVED	= 0xC0
+
+# OS
+GZIP_OS_MSDOS	= 0
+GZIP_OS_AMIGA	= 1
+GZIP_OS_VMS	= 2
+GZIP_OS_UNIX	= 3
+GZIP_OS_VMCMS	= 4
+GZIP_OS_ATARI	= 5
+GZIP_OS_OS2	= 6
+GZIP_OS_MACOS	= 7
+GZIP_OS_ZSYSTEM	= 8
+GZIP_OS_CPM	= 9
+GZIP_OS_TOPS20	= 10
+GZIP_OS_WIN32	= 11
+GZIP_OS_QDOS	= 12
+GZIP_OS_RISCOS	= 13
+GZIP_OS_UNKNOWN	= 255
+
+GZIP_FENCRYPT_LEN	= 12
+
+class GzipExtra(dpkt.Packet):
+    __hdr__ = (
+        ('id', '2s', ''),
+        ('len', 'H', 0)
+        )
+
+class Gzip(dpkt.Packet):
+    __hdr__ = (
+        ('magic', '2s', GZIP_MAGIC),
+        ('method', 'B', GZIP_MDEFLATE),
+        ('flags', 'B', 0),
+        ('mtime', 'I', 0),
+        ('xflags', 'B', 0),
+        ('os', 'B', GZIP_OS_UNIX),
+        
+        ('extra', '0s', ''),	# XXX - GZIP_FEXTRA
+        ('filename', '0s', ''),	# XXX - GZIP_FNAME
+        ('comment', '0s', '')	# XXX - GZIP_FCOMMENT
+        )
+    
+    def unpack(self, buf):
+        super(Gzip, self).unpack(buf)
+        if self.flags & GZIP_FEXTRA:
+            n = struct.unpack(self.data[:2], '>H')[0]
+            self.extra = GzipExtra(self.data[2:2+n])
+            self.data = self.data[2+n:]
+        if self.flags & GZIP_FNAME:
+            n = self.data.find('\x00')
+            self.filename = self.data[:n]
+            self.data = self.data[n + 1:]
+        if self.flags & GZIP_FCOMMENT:
+            n = self.data.find('\x00')
+            self.comment = self.data[:n]
+            self.data = self.data[n + 1:]
+        if self.flags & GZIP_FENCRYPT:
+            self.data = self.data[GZIP_FENCRYPT_LEN:]	# XXX - skip
+        if self.flags & GZIP_FHCRC:
+            self.data = self.data[2:]	# XXX - skip
+
+    def pack_hdr(self):
+        l = []
+        if self.extra:
+            self.flags |= GZIP_FEXTRA
+            s = str(self.extra)
+            l.append(struct.pack('>H', len(s)))
+            l.append(s)
+        if self.filename:
+            self.flags |= GZIP_FNAME
+            l.append(self.filename)
+            l.append('\x00')
+        if self.comment:
+            self.flags |= GZIP_FCOMMENT
+            l.append(self.comment)
+            l.append('\x00')
+        l.insert(0, super(Gzip, self).pack_hdr())
+        return ''.join(l)
+
+    def compress(self):
+        """Compress self.data."""
+        c = zlib.compressobj(9, zlib.DEFLATED, -zlib.MAX_WBITS,
+                             zlib.DEF_MEM_LEVEL, 0)
+        self.data = c.compress(self.data)
+    
+    def decompress(self):
+        """Return decompressed payload."""
+        d = zlib.decompressobj(-zlib.MAX_WBITS)
+        return d.decompress(self.data)
+
+if __name__ == '__main__':
+    import sys
+    gz = Gzip(open(sys.argv[1]).read())
+    print `gz`, `gz.decompress()`