net: ipv4: Add raw variants of various IPv4 functions

To address the misaligned access issues reported by UBSAN, introduce raw
variant of certain IPv4 functions used in the critical data path of the
network stack, operating on plain uint8_t buffers in stead of IPv4
address struct.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>

Author: rlubos

include/zephyr/net/net_ip.h

@@ -829,6 +829,13 @@ static inline void net_ipv6_addr_prefix_mask(const uint8_t *inaddr,
 	outaddr[bytes] = inaddr[bytes] & mask;
 }
 
+/** @cond INTERNAL_HIDDEN */
+static inline bool net_ipv4_is_addr_loopback_raw(const uint8_t *addr)
+{
+	return addr[0] == 127U;
+}
+/** @endcond */
+
 /**
  * @brief Check if the IPv4 address is a loopback address (127.0.0.0/8).
  *
@@ -838,8 +845,15 @@ static inline void net_ipv6_addr_prefix_mask(const uint8_t *inaddr,
  */
 static inline bool net_ipv4_is_addr_loopback(struct in_addr *addr)
 {
-	return addr->s4_addr[0] == 127U;
+	return net_ipv4_is_addr_loopback_raw(addr->s4_addr);
+}
+
+/** @cond INTERNAL_HIDDEN */
+static inline bool net_ipv4_is_addr_unspecified_raw(const uint8_t *addr)
+{
+	return UNALIGNED_GET((uint32_t *)addr) == 0;
 }
+/** @endcond */
 
 /**
  *  @brief Check if the IPv4 address is unspecified (all bits zero)
@@ -850,9 +864,16 @@ static inline bool net_ipv4_is_addr_loopback(struct in_addr *addr)
  */
 static inline bool net_ipv4_is_addr_unspecified(const struct in_addr *addr)
 {
-	return UNALIGNED_GET(&addr->s_addr) == 0;
+	return net_ipv4_is_addr_unspecified_raw(addr->s4_addr);
 }
 
+/** @cond INTERNAL_HIDDEN */
+static inline bool net_ipv4_is_addr_mcast_raw(const uint8_t *addr)
+{
+	return (ntohl(UNALIGNED_GET((uint32_t *)addr)) & 0xF0000000) == 0xE0000000;
+}
+/** @endcond */
+
 /**
  * @brief Check if the IPv4 address is a multicast address.
  *
@@ -862,8 +883,15 @@ static inline bool net_ipv4_is_addr_unspecified(const struct in_addr *addr)
  */
 static inline bool net_ipv4_is_addr_mcast(const struct in_addr *addr)
 {
-	return (ntohl(UNALIGNED_GET(&addr->s_addr)) & 0xF0000000) == 0xE0000000;
+	return net_ipv4_is_addr_mcast_raw(addr->s4_addr);
+}
+
+/** @cond INTERNAL_HIDDEN */
+static inline bool net_ipv4_is_ll_addr_raw(const uint8_t *addr)
+{
+	return (ntohl(UNALIGNED_GET((uint32_t *)addr)) & 0xFFFF0000) == 0xA9FE0000;
 }
+/** @endcond */
 
 /**
  * @brief Check if the given IPv4 address is a link local address.
@@ -874,7 +902,7 @@ static inline bool net_ipv4_is_addr_mcast(const struct in_addr *addr)
  */
 static inline bool net_ipv4_is_ll_addr(const struct in_addr *addr)
 {
-	return (ntohl(UNALIGNED_GET(&addr->s_addr)) & 0xFFFF0000) == 0xA9FE0000;
+	return net_ipv4_is_ll_addr_raw(addr->s4_addr);
 }
 
 /**
@@ -941,32 +969,31 @@ static inline void net_ipv6_addr_copy_raw(uint8_t *dest,
 }
 
 /**
- *  @brief Compare two IPv4 addresses
+ *  @brief Compare two raw IPv4 address buffers
  *
- *  @param addr1 Pointer to IPv4 address.
- *  @param addr2 Pointer to IPv4 address.
+ *  @param addr1 Pointer to IPv4 address buffer.
+ *  @param addr2 Pointer to IPv4 address buffer.
  *
  *  @return True if the addresses are the same, false otherwise.
  */
-static inline bool net_ipv4_addr_cmp(const struct in_addr *addr1,
-				     const struct in_addr *addr2)
+static inline bool net_ipv4_addr_cmp_raw(const uint8_t *addr1,
+					 const uint8_t *addr2)
 {
-	return UNALIGNED_GET(&addr1->s_addr) == UNALIGNED_GET(&addr2->s_addr);
+	return UNALIGNED_GET((uint32_t *)addr1) == UNALIGNED_GET((uint32_t *)addr2);
 }
 
 /**
- *  @brief Compare two raw IPv4 address buffers
+ *  @brief Compare two IPv4 addresses
  *
- *  @param addr1 Pointer to IPv4 address buffer.
- *  @param addr2 Pointer to IPv4 address buffer.
+ *  @param addr1 Pointer to IPv4 address.
+ *  @param addr2 Pointer to IPv4 address.
  *
  *  @return True if the addresses are the same, false otherwise.
  */
-static inline bool net_ipv4_addr_cmp_raw(const uint8_t *addr1,
-					 const uint8_t *addr2)
+static inline bool net_ipv4_addr_cmp(const struct in_addr *addr1,
+				     const struct in_addr *addr2)
 {
-	return net_ipv4_addr_cmp((const struct in_addr *)addr1,
-				 (const struct in_addr *)addr2);
+	return net_ipv4_addr_cmp_raw(addr1->s4_addr, addr2->s4_addr);
 }
 
 /**
@@ -1114,6 +1141,32 @@ static inline bool net_ipv4_addr_mask_cmp(struct net_if *iface,
 	return net_if_ipv4_addr_mask_cmp(iface, addr);
 }
 
+/** @cond INTERNAL_HIDDEN */
+extern bool net_if_ipv4_is_addr_bcast_raw(struct net_if *iface,
+					  const uint8_t *addr);
+
+#if defined(CONFIG_NET_NATIVE_IPV4)
+static inline bool net_ipv4_is_addr_bcast_raw(struct net_if *iface,
+					      const uint8_t *addr)
+{
+	if (net_ipv4_addr_cmp_raw(addr, net_ipv4_broadcast_address()->s4_addr)) {
+		return true;
+	}
+
+	return net_if_ipv4_is_addr_bcast_raw(iface, addr);
+}
+#else
+static inline bool net_ipv4_is_addr_bcast_raw(struct net_if *iface,
+					      const uint8_t *addr)
+{
+	ARG_UNUSED(iface);
+	ARG_UNUSED(addr);
+
+	return false;
+}
+#endif
+/** @endcond */
+
 extern bool net_if_ipv4_is_addr_bcast(struct net_if *iface,
 				      const struct in_addr *addr);
 
@@ -1146,6 +1199,23 @@ static inline bool net_ipv4_is_addr_bcast(struct net_if *iface,
 }
 #endif
 
+/** @cond INTERNAL_HIDDEN */
+extern struct net_if_addr *net_if_ipv4_addr_lookup_raw(const uint8_t *addr,
+						       struct net_if **ret);
+
+static inline bool net_ipv4_is_my_addr_raw(const uint8_t *addr)
+{
+	bool ret;
+
+	ret = net_if_ipv4_addr_lookup_raw(addr, NULL) != NULL;
+	if (!ret) {
+		ret = net_ipv4_is_addr_bcast_raw(NULL, addr);
+	}
+
+	return ret;
+}
+/** @endcond */
+
 extern struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
 						   struct net_if **iface);
 

subsys/net/ip/net_if.c

@@ -3658,7 +3658,7 @@ bool net_if_ipv4_addr_mask_cmp(struct net_if *iface,
 }
 
 static bool ipv4_is_broadcast_address(struct net_if *iface,
-				      const struct in_addr *addr)
+				      const uint8_t *addr)
 {
 	struct net_if_ipv4 *ipv4;
 	bool ret = false;
@@ -3681,7 +3681,7 @@ static bool ipv4_is_broadcast_address(struct net_if *iface,
 		bcast.s_addr = ipv4->unicast[i].ipv4.address.in_addr.s_addr |
 			       ~ipv4->unicast[i].netmask.s_addr;
 
-		if (bcast.s_addr == UNALIGNED_GET(&addr->s_addr)) {
+		if (bcast.s_addr == UNALIGNED_GET((uint32_t *)addr)) {
 			ret = true;
 			goto out;
 		}
@@ -3692,8 +3692,8 @@ static bool ipv4_is_broadcast_address(struct net_if *iface,
 	return ret;
 }
 
-bool net_if_ipv4_is_addr_bcast(struct net_if *iface,
-			       const struct in_addr *addr)
+bool net_if_ipv4_is_addr_bcast_raw(struct net_if *iface,
+				   const uint8_t *addr)
 {
 	bool ret = false;
 
@@ -3713,6 +3713,12 @@ bool net_if_ipv4_is_addr_bcast(struct net_if *iface,
 	return ret;
 }
 
+bool net_if_ipv4_is_addr_bcast(struct net_if *iface,
+			       const struct in_addr *addr)
+{
+	return net_if_ipv4_is_addr_bcast_raw(iface, addr->s4_addr);
+}
+
 struct net_if *net_if_ipv4_select_src_iface_addr(const struct in_addr *dst,
 						 const struct in_addr **src_addr)
 {
@@ -3987,8 +3993,8 @@ struct net_if_addr *net_if_ipv4_addr_get_first_by_index(int ifindex)
 	return ifaddr;
 }
 
-struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
-					    struct net_if **ret)
+struct net_if_addr *net_if_ipv4_addr_lookup_raw(const uint8_t *addr,
+						struct net_if **ret)
 {
 	struct net_if_addr *ifaddr = NULL;
 
@@ -4009,7 +4015,7 @@ struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
 				continue;
 			}
 
-			if (UNALIGNED_GET(&addr->s4_addr32[0]) ==
+			if (UNALIGNED_GET((uint32_t *)addr) ==
 			    ipv4->unicast[i].ipv4.address.in_addr.s_addr) {
 
 				if (ret) {
@@ -4029,6 +4035,12 @@ struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
 	return ifaddr;
 }
 
+struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
+					    struct net_if **ret)
+{
+	return net_if_ipv4_addr_lookup_raw(addr->s4_addr, ret);
+}
+
 int z_impl_net_if_ipv4_addr_lookup_by_index(const struct in_addr *addr)
 {
 	struct net_if_addr *if_addr;