Index: uspace/srv/net/tcp/tcp_header.h
===================================================================
--- uspace/srv/net/tcp/tcp_header.h	(revision 49ff5f3d72bdc099cbcb1c649dfa55c1104f1244)
+++ uspace/srv/net/tcp/tcp_header.h	(revision 49ff5f3d72bdc099cbcb1c649dfa55c1104f1244)
@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) 2009 Lukas Mejdrech
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup tcp
+ * @{
+ */
+
+/** @file
+ * TCP header definition.
+ * Based on the RFC 793.
+ */
+
+#ifndef NET_TCP_HEADER_H_
+#define NET_TCP_HEADER_H_
+
+#include <sys/types.h>
+
+/** TCP header size in bytes. */
+#define TCP_HEADER_SIZE				sizeof(tcp_header_t)
+
+/** Returns the actual TCP header length in bytes.
+ * @param[in] header The TCP packet header.
+ */
+#define TCP_HEADER_LENGTH(header)		(GET_TCP_HEADER_LENGTH(header) * 4U)
+
+/** Returns the TCP header length.
+ * @param[in] length The TCP header length in bytes.
+ */
+#define TCP_COMPUTE_HEADER_LENGTH(length)	((uint8_t) ((length) / 4U))
+
+/** Type definition of the transmission datagram header.
+ * @see tcp_header
+ */
+typedef struct tcp_header tcp_header_t;
+
+/** Type definition of the transmission datagram header option.
+ * @see tcp_option
+ */
+typedef struct tcp_option tcp_option_t;
+
+/** Type definition of the Maximum segment size TCP option. */
+typedef struct tcp_max_segment_size_option tcp_max_segment_size_option_t;
+
+/** Transmission datagram header. */
+struct tcp_header {
+	uint16_t source_port;
+	uint16_t destination_port;
+	uint32_t sequence_number;
+	uint32_t acknowledgement_number;
+
+	uint8_t hlr; /* header length, reserved1 */
+
+#define GET_TCP_HEADER_LENGTH(header) \
+	(((header)->hlr & 0xf0) >> 4)
+#define SET_TCP_HEADER_LENGTH(header, length) \
+	((header)->hlr = \
+	 ((length & 0x0f) << 4) | ((header)->hlr & 0x0f))
+
+#define GET_TCP_HEADER_RESERVED1(header) \
+	((header)->hlr & 0x0f)
+#define SET_TCP_HEADER_RESERVED1(header, reserved1) \
+	((header)->hlr = \
+	 (reserved1 & 0x0f) | ((header)->hlr & 0xf0))
+
+	/* reserved2, urgent, acknowledge, push, reset, synchronize, finalize */
+	uint8_t ruaprsf;  
+
+#define GET_TCP_HEADER_RESERVED2(header) \
+	(((header)->ruaprsf & 0xc0) >> 6)
+#define SET_TCP_HEADER_RESERVED2(header, reserved2) \
+	((header)->ruaprsf = \
+	 ((reserved2 & 0x03) << 6) | ((header)->ruaprsf & 0x3f))
+
+#define GET_TCP_HEADER_URGENT(header) \
+	(((header)->ruaprsf & 0x20) >> 5)
+#define SET_TCP_HEADER_URGENT(header, urgent) \
+	((header)->ruaprsf = \
+	 ((urgent & 0x01) << 5) | ((header)->ruaprsf & 0xdf))
+
+#define GET_TCP_HEADER_ACKNOWLEDGE(header) \
+	(((header)->ruaprsf & 0x10) >> 4)
+#define SET_TCP_HEADER_ACKNOWLEDGE(header, acknowledge) \
+	((header)->ruaprsf = \
+	 ((acknowledge & 0x01) << 4) | ((header)->ruaprsf & 0xef))
+
+#define GET_TCP_HEADER_PUSH(header) \
+	(((header)->ruaprsf & 0x08) >> 3)
+#define SET_TCP_HEADER_PUSH(header, push) \
+	((header)->ruaprsf = \
+	 ((push & 0x01) << 3) | ((header)->ruaprsf & 0xf7))
+
+#define GET_TCP_HEADER_RESET(header) \
+	(((header)->ruaprsf & 0x04) >> 2)
+#define SET_TCP_HEADER_RESET(header, reset) \
+	((header)->ruaprsf = \
+	 ((reset & 0x01) << 2) | ((header)->ruaprsf & 0xfb))
+
+#define GET_TCP_HEADER_SYNCHRONIZE(header) \
+	(((header)->ruaprsf & 0x02) >> 1)
+#define SET_TCP_HEADER_SYNCHRONIZE(header, synchronize) \
+	((header)->ruaprsf = \
+	 ((synchronize & 0x01) << 1) | ((header)->ruaprsf & 0xfd))
+
+#define GET_TCP_HEADER_FINALIZE(header) \
+	((header)->ruaprsf & 0x01)
+#define SET_TCP_HEADER_FINALIZE(header, finalize) \
+	((header)->ruaprsf = \
+	 (finalize & 0x01) | ((header)->ruaprsf & 0xfe))
+
+	uint16_t window;
+	uint16_t checksum;
+	uint16_t urgent_pointer;
+} __attribute__ ((packed));
+
+/** Transmission datagram header option. */
+struct tcp_option {
+	/** Option type. */
+	uint8_t type;
+	/** Option length. */
+	uint8_t length;
+};
+
+/** Maximum segment size TCP option. */
+struct tcp_max_segment_size_option {
+	/** TCP option.
+	 * @see TCPOPT_MAX_SEGMENT_SIZE
+	 * @see TCPOPT_MAX_SEGMENT_SIZE_LENGTH
+	 */
+	tcp_option_t option;
+	
+	/** Maximum segment size in bytes. */
+	uint16_t max_segment_size;
+} __attribute__ ((packed));
+
+#endif
+
+/** @}
+ */