Support multiple IPv4 netmasks per interface

drivers/modem/hl7800.c

@@ -2168,7 +2168,9 @@ static bool on_cmd_atcmdinfo_ipaddr(struct net_buf **buf, uint16_t len)
 				LOG_ERR("Cannot set iface IPv4 addr");
 			}
 
-			net_if_ipv4_set_netmask(iface_ctx.iface, &iface_ctx.subnet);
+			net_if_ipv4_set_netmask_by_addr(iface_ctx.iface,
+							&new_ipv4_addr,
+							&iface_ctx.subnet);
 			net_if_ipv4_set_gw(iface_ctx.iface, &iface_ctx.gateway);
 #endif
 			/* store the new IP addr */

drivers/net/loopback.c

@@ -50,7 +50,7 @@ static void loopback_init(struct net_if *iface)
 			LOG_ERR("Failed to register IPv4 loopback address");
 		}
 
-		net_if_ipv4_set_netmask(iface, &netmask);
+		net_if_ipv4_set_netmask_by_addr(iface, &ipv4_loopback, &netmask);
 	}
 
 	if (IS_ENABLED(CONFIG_NET_IPV6)) {

drivers/wifi/esp_at/esp.c

@@ -514,13 +514,13 @@ static void esp_ip_addr_work(struct k_work *work)
 
 #if defined(CONFIG_NET_NATIVE_IPV4)
 	/* update interface addresses */
-	net_if_ipv4_set_gw(dev->net_iface, &dev->gw);
-	net_if_ipv4_set_netmask(dev->net_iface, &dev->nm);
 #if defined(CONFIG_WIFI_ESP_AT_IP_STATIC)
 	net_if_ipv4_addr_add(dev->net_iface, &dev->ip, NET_ADDR_MANUAL, 0);
 #else
 	net_if_ipv4_addr_add(dev->net_iface, &dev->ip, NET_ADDR_DHCP, 0);
 #endif
+	net_if_ipv4_set_gw(dev->net_iface, &dev->gw);
+	net_if_ipv4_set_netmask_by_addr(dev->net_iface, &dev->ip, &dev->nm);
 #endif
 
 	if (IS_ENABLED(CONFIG_WIFI_ESP_AT_DNS_USE)) {

drivers/wifi/eswifi/eswifi_core.c

@@ -677,8 +677,8 @@ static int eswifi_mgmt_ap_enable(const struct device *dev,
 
 	/* Set IP Address */
 	for (i = 0; ipv4 && i < NET_IF_MAX_IPV4_ADDR; i++) {
-		if (ipv4->unicast[i].is_used) {
-			unicast = &ipv4->unicast[i];
+		if (ipv4->unicast[i].ipv4.is_used) {
+			unicast = &ipv4->unicast[i].ipv4;
 			break;
 		}
 	}

include/zephyr/net/net_if.h

@@ -368,19 +368,28 @@ struct net_if_dhcpv6 {
 #endif
 /** @endcond */
 
+/**
+ * @brief Network Interface unicast IPv4 address and netmask
+ *
+ * Stores the unicast IPv4 address and related netmask.
+ */
+struct net_if_addr_ipv4 {
+	/** IPv4 address */
+	struct net_if_addr ipv4;
+	/** Netmask */
+	struct in_addr netmask;
+};
+
 struct net_if_ipv4 {
 	/** Unicast IP addresses */
-	struct net_if_addr unicast[NET_IF_MAX_IPV4_ADDR];
+	struct net_if_addr_ipv4 unicast[NET_IF_MAX_IPV4_ADDR];
 
 	/** Multicast IP addresses */
 	struct net_if_mcast_addr mcast[NET_IF_MAX_IPV4_MADDR];
 
 	/** Gateway */
 	struct in_addr gw;
 
-	/** Netmask */
-	struct in_addr netmask;
-
 	/** IPv4 time-to-live */
 	uint8_t ttl;
 
@@ -2279,34 +2288,78 @@ struct in_addr *net_if_ipv4_get_ll(struct net_if *iface,
 struct in_addr *net_if_ipv4_get_global_addr(struct net_if *iface,
 					    enum net_addr_state addr_state);
 
+/**
+ * @brief Get IPv4 netmask related to an address of an interface.
+ *
+ * @param iface Interface to use.
+ * @param addr IPv4 address to check.
+ *
+ * @return The netmask set on the interface related to the give address,
+ *         unspecified address if not found.
+ */
+struct in_addr net_if_ipv4_get_netmask_by_addr(struct net_if *iface,
+					       const struct in_addr *addr);
+
 /**
  * @brief Get IPv4 netmask of an interface.
  *
+ * @deprecated Use net_if_ipv4_get_netmask_by_addr() instead.
+ *
  * @param iface Interface to use.
  *
  * @return The netmask set on the interface, unspecified address if not found.
  */
-struct in_addr net_if_ipv4_get_netmask(struct net_if *iface);
+__deprecated struct in_addr net_if_ipv4_get_netmask(struct net_if *iface);
 
 /**
  * @brief Set IPv4 netmask for an interface.
  *
+ * @deprecated Use net_if_ipv4_set_netmask_by_addr() instead.
+ *
  * @param iface Interface to use.
  * @param netmask IPv4 netmask
  */
-void net_if_ipv4_set_netmask(struct net_if *iface,
-			     const struct in_addr *netmask);
+__deprecated void net_if_ipv4_set_netmask(struct net_if *iface,
+					  const struct in_addr *netmask);
 
 /**
  * @brief Set IPv4 netmask for an interface index.
  *
+ * @deprecated Use net_if_ipv4_set_netmask_by_addr() instead.
+ *
+ * @param index Network interface index
+ * @param netmask IPv4 netmask
+ *
+ * @return True if netmask was added, false otherwise.
+ */
+__deprecated __syscall bool net_if_ipv4_set_netmask_by_index(int index,
+							     const struct in_addr *netmask);
+
+/**
+ * @brief Set IPv4 netmask for an interface index for a given address.
+ *
  * @param index Network interface index
+ * @param addr IPv4 address related to this netmask
+ * @param netmask IPv4 netmask
+ *
+ * @return True if netmask was added, false otherwise.
+ */
+__syscall bool net_if_ipv4_set_netmask_by_addr_by_index(int index,
+							const struct in_addr *addr,
+							const struct in_addr *netmask);
+
+/**
+ * @brief Set IPv4 netmask for an interface index for a given address.
+ *
+ * @param iface Network interface
+ * @param addr IPv4 address related to this netmask
  * @param netmask IPv4 netmask
  *
  * @return True if netmask was added, false otherwise.
  */
-__syscall bool net_if_ipv4_set_netmask_by_index(int index,
-						const struct in_addr *netmask);
+bool net_if_ipv4_set_netmask_by_addr(struct net_if *iface,
+				     const struct in_addr *addr,
+				     const struct in_addr *netmask);
 
 /**
  * @brief Set IPv4 gateway for an interface.

samples/boards/nxp_s32/netc/src/main.c

@@ -54,12 +54,14 @@ static int setup_iface(struct net_if *iface, const char *ipv6_addr,
 		LOG_INF("IPv4 address: %s", ipv4_addr);
 
 		if (netmask && netmask[0]) {
-			if (net_addr_pton(AF_INET, netmask, &addr4)) {
+			struct in_addr nm;
+
+			if (net_addr_pton(AF_INET, netmask, &nm)) {
 				LOG_ERR("Invalid netmask: %s", netmask);
 				return -EINVAL;
 			}
 
-			net_if_ipv4_set_netmask(iface, &addr4);
+			net_if_ipv4_set_netmask_by_addr(iface, &addr4, &nm);
 		}
 	}
 

samples/net/dhcpv4_client/src/main.c

@@ -50,18 +50,18 @@ static void handler(struct net_mgmt_event_callback *cb,
 	for (i = 0; i < NET_IF_MAX_IPV4_ADDR; i++) {
 		char buf[NET_IPV4_ADDR_LEN];
 
-		if (iface->config.ip.ipv4->unicast[i].addr_type !=
+		if (iface->config.ip.ipv4->unicast[i].ipv4.addr_type !=
 							NET_ADDR_DHCP) {
 			continue;
 		}
 
 		LOG_INF("   Address[%d]: %s", net_if_get_by_iface(iface),
 			net_addr_ntop(AF_INET,
-			    &iface->config.ip.ipv4->unicast[i].address.in_addr,
+			    &iface->config.ip.ipv4->unicast[i].ipv4.address.in_addr,
 						  buf, sizeof(buf)));
 		LOG_INF("    Subnet[%d]: %s", net_if_get_by_iface(iface),
 			net_addr_ntop(AF_INET,
-				       &iface->config.ip.ipv4->netmask,
+				       &iface->config.ip.ipv4->unicast[i].netmask,
 				       buf, sizeof(buf)));
 		LOG_INF("    Router[%d]: %s", net_if_get_by_iface(iface),
 			net_addr_ntop(AF_INET,

samples/net/dns_resolve/src/main.c

@@ -168,6 +168,7 @@ static void print_dhcpv4_addr(struct net_if *iface, struct net_if_addr *if_addr,
 {
 	bool *found = (bool *)user_data;
 	char hr_addr[NET_IPV4_ADDR_LEN];
+	struct in_addr netmask;
 
 	if (*found) {
 		return;
@@ -181,10 +182,11 @@ static void print_dhcpv4_addr(struct net_if *iface, struct net_if_addr *if_addr,
 		net_addr_ntop(AF_INET, &if_addr->address.in_addr,
 			      hr_addr, NET_IPV4_ADDR_LEN));
 	LOG_INF("Lease time: %u seconds", iface->config.dhcpv4.lease_time);
+
+	netmask = net_if_ipv4_get_netmask_by_addr(iface,
+						  &if_addr->address.in_addr);
 	LOG_INF("Subnet: %s",
-		net_addr_ntop(AF_INET,
-			      &iface->config.ip.ipv4->netmask,
-			      hr_addr, NET_IPV4_ADDR_LEN));
+		net_addr_ntop(AF_INET, &netmask, hr_addr, NET_IPV4_ADDR_LEN));
 	LOG_INF("Router: %s",
 		net_addr_ntop(AF_INET,
 			      &iface->config.ip.ipv4->gw,

samples/net/ipv4_autoconf/src/main.c

@@ -41,13 +41,17 @@ static void handler(struct net_mgmt_event_callback *cb,
 	for (i = 0; i < NET_IF_MAX_IPV4_ADDR; i++) {
 		char buf[NET_IPV4_ADDR_LEN];
 
-		if (cfg->ip.ipv4->unicast[i].addr_type != NET_ADDR_AUTOCONF) {
+		if (cfg->ip.ipv4->unicast[i].ipv4.addr_type != NET_ADDR_AUTOCONF) {
 			continue;
 		}
 
 		LOG_INF("Your address: %s",
 			net_addr_ntop(AF_INET,
-				    &cfg->ip.ipv4->unicast[i].address.in_addr,
+				    &cfg->ip.ipv4->unicast[i].ipv4.address.in_addr,
+				    buf, sizeof(buf)));
+		LOG_INF("Your netmask: %s",
+			net_addr_ntop(AF_INET,
+				    &cfg->ip.ipv4->unicast[i].netmask,
 				    buf, sizeof(buf)));
 	}
 }

samples/net/mdns_responder/src/vlan.c

@@ -86,12 +86,14 @@ static int setup_iface(struct net_if *iface, const char *ipv6_addr,
 		}
 
 		if (netmask && netmask[0]) {
-			if (net_addr_pton(AF_INET, netmask, &addr4)) {
+			struct in_addr nm;
+
+			if (net_addr_pton(AF_INET, netmask, &nm)) {
 				LOG_ERR("Invalid netmask: %s", ipv4_addr);
 				return -EINVAL;
 			}
 
-			net_if_ipv4_set_netmask(iface, &addr4);
+			net_if_ipv4_set_netmask_by_addr(iface, &addr4, &nm);
 		}
 	}
 

samples/net/sockets/echo_server/src/vlan.c

@@ -86,12 +86,14 @@ static int setup_iface(struct net_if *iface, const char *ipv6_addr,
 		}
 
 		if (netmask && netmask[0]) {
-			if (net_addr_pton(AF_INET, netmask, &addr4)) {
+			struct in_addr nm;
+
+			if (net_addr_pton(AF_INET, netmask, &nm)) {
 				LOG_ERR("Invalid netmask: %s", ipv4_addr);
 				return -EINVAL;
 			}
 
-			net_if_ipv4_set_netmask(iface, &addr4);
+			net_if_ipv4_set_netmask_by_addr(iface, &addr4, &nm);
 		}
 	}
 

samples/net/virtual/src/main.c

@@ -302,12 +302,14 @@ static int setup_iface(struct net_if *iface,
 		}
 
 		if (netmask) {
-			if (net_addr_pton(AF_INET, netmask, &addr4)) {
+			struct in_addr nm;
+
+			if (net_addr_pton(AF_INET, netmask, &nm)) {
 				LOG_ERR("Invalid netmask: %s", netmask);
 				return -EINVAL;
 			}
 
-			net_if_ipv4_set_netmask(iface, &addr4);
+			net_if_ipv4_set_netmask_by_addr(iface, &addr4, &nm);
 		}
 
 		if (!peer4addr || *peer4addr == '\0') {

samples/subsys/mgmt/hawkbit/src/dhcp.c

@@ -22,24 +22,15 @@ static void handler(struct net_mgmt_event_callback *cb,
 		    uint32_t mgmt_event,
 		    struct net_if *iface)
 {
-	int i;
 	bool notified = false;
 
-	if (mgmt_event != NET_EVENT_IPV4_ADDR_ADD) {
+	if (mgmt_event != NET_EVENT_IPV4_DHCP_BOUND) {
 		return;
 	}
 
-	for (i = 0; i < NET_IF_MAX_IPV4_ADDR; i++) {
-		if (iface->config.ip.ipv4->unicast[i].addr_type !=
-		    NET_ADDR_DHCP) {
-			continue;
-		}
-
-		if (!notified) {
-			k_sem_give(&got_address);
-			notified = true;
-		}
-		break;
+	if (!notified) {
+		k_sem_give(&got_address);
+		notified = true;
 	}
 }
 
@@ -51,7 +42,7 @@ void app_dhcpv4_startup(void)
 	struct net_if *iface;
 
 	net_mgmt_init_event_callback(&mgmt_cb, handler,
-				     NET_EVENT_IPV4_ADDR_ADD);
+				     NET_EVENT_IPV4_DHCP_BOUND);
 	net_mgmt_add_event_callback(&mgmt_cb);
 
 	iface = net_if_get_default();

subsys/net/ip/ipv4_autoconf.c

@@ -182,7 +182,9 @@ static inline void ipv4_autoconf_addr_set(struct net_if_ipv4_autoconf *ipv4auto)
 		return;
 	}
 
-	net_if_ipv4_set_netmask(ipv4auto->iface, &netmask);
+	net_if_ipv4_set_netmask_by_addr(ipv4auto->iface,
+					&ipv4auto->requested_ip,
+					&netmask);
 
 	ipv4auto->state = NET_IPV4_AUTOCONF_ASSIGNED;
 }