Index: uspace/lib/net/il/ip_client.c
===================================================================
--- uspace/lib/net/il/ip_client.c	(revision ccca251bb0673718b534366ace0e22857d73804b)
+++ uspace/lib/net/il/ip_client.c	(revision 40ffda8c66dc2c631d4b6944acb463ef338a5926)
@@ -181,6 +181,6 @@
 	/* Set the header */
 	header = (ip_header_t *) data;
-	header->header_length = IP_COMPUTE_HEADER_LENGTH(sizeof(ip_header_t) +
-	    ipopt_length);
+	SET_HEADER_LENGTH(header, (IP_COMPUTE_HEADER_LENGTH(sizeof(ip_header_t)
+        + ipopt_length)));
 	header->ttl = (ttl ? ttl : IPDEFTTL);
 	header->tos = tos;
@@ -188,5 +188,5 @@
 
 	if (dont_fragment)
-		header->flags = IPFLAG_DONT_FRAGMENT;
+		SET_HEADER_FLAGS(header, IPFLAG_DONT_FRAGMENT);
 
 	return EOK;
@@ -227,5 +227,5 @@
 		*tos = header->tos;
 	if (dont_fragment)
-		*dont_fragment = header->flags & IPFLAG_DONT_FRAGMENT;
+		*dont_fragment = GET_HEADER_FLAGS(header) & IPFLAG_DONT_FRAGMENT;
 	if (ipopt_length) {
 		*ipopt_length = IP_HEADER_LENGTH(header) - sizeof(ip_header_t);
Index: uspace/lib/net/include/ip_header.h
===================================================================
--- uspace/lib/net/include/ip_header.h	(revision ccca251bb0673718b534366ace0e22857d73804b)
+++ uspace/lib/net/include/ip_header.h	(revision 40ffda8c66dc2c631d4b6944acb463ef338a5926)
@@ -64,5 +64,5 @@
  */
 #define IP_FRAGMENT_OFFSET(header) \
-	((((header)->fragment_offset_high << 8) + \
+	(((GET_HEADER_FRAGMENT_OFFSET_HIGH(header) << 8) + \
 	    (header)->fragment_offset_low) * 8U)
 
@@ -83,5 +83,5 @@
  */
 #define IP_HEADER_LENGTH(header) \
-	((header)->header_length * 4U)
+	(GET_HEADER_LENGTH(header) * 4U)
 
 /** Returns the actual IP packet total length.
@@ -143,11 +143,17 @@
  */
 struct ip_header {
-#ifdef ARCH_IS_BIG_ENDIAN
-	uint8_t version : 4;
-	uint8_t header_length : 4;
-#else
-	uint8_t header_length : 4;
-	uint8_t version : 4;
-#endif
+	uint8_t vhl; /* version, header_length */
+
+#define GET_HEADER_VERSION(header) \
+	(((header)->vhl & 0xf0) >> 4)
+#define SET_HEADER_VERSION(header, version) \
+	((header)->vhl = \
+	 ((version & 0x0f) << 4) | ((header)->vhl & 0x0f))
+
+#define GET_HEADER_LENGTH(header) \
+	((header)->vhl & 0x0f)
+#define SET_HEADER_LENGTH(header, length) \
+	((header)->vhl = \
+	 (length & 0x0f) | ((header)->vhl & 0xf0))
 
 	uint8_t tos;
@@ -155,11 +161,17 @@
 	uint16_t identification;
 
-#ifdef ARCH_IS_BIG_ENDIAN
-	uint8_t flags : 3;
-	uint8_t fragment_offset_high : 5;
-#else
-	uint8_t fragment_offset_high : 5;
-	uint8_t flags : 3;
-#endif
+	uint8_t ffoh; /* flags, fragment_offset_high */
+
+#define GET_HEADER_FLAGS(header) \
+	(((header)->ffoh & 0xe0) >> 5)
+#define SET_HEADER_FLAGS(header, flags) \
+	((header)->ffoh = \
+	 ((flags & 0x07) << 5) | ((header)->ffoh & 0x1f))
+
+#define GET_HEADER_FRAGMENT_OFFSET_HIGH(header) \
+	((header)->ffoh & 0x1f)
+#define SET_HEADER_FRAGMENT_OFFSET_HIGH(header, fragment_offset_high) \
+	((header)->ffoh = \
+	 (fragment_offset_high & 0x1f) | ((header)->ffoh & 0xe0))
 
 	uint8_t fragment_offset_low;
@@ -181,11 +193,18 @@
 	uint8_t pointer;
 
-#ifdef ARCH_IS_BIG_ENDIAN
-	uint8_t overflow : 4;
-	uint8_t flags : 4;
-#else
-	uint8_t flags : 4;
-	uint8_t overflow : 4;
-#endif
+	uint8_t of; /* overflow, flags */
+
+#define GET_OPTION_OVERFLOW(option) \
+	(((option)->of & 0xf0) >> 4)
+#define SET_OPTION_OVERFLOW(option, overflow) \
+	((option)->of = \
+	 ((overflow & 0x0f) << 4) | ((option)->of & 0x0f))
+
+#define GET_OPTION_FLAGS(option) \
+	((option)->of & 0x0f)
+#define SET_OPTION_FLAGS(option, flags) \
+	((option)->of = \
+	 (flags & 0x0f) | ((option)->of & 0xf0))
+
 } __attribute__ ((packed));