net: if: Add syscall interface to IP address add and rm

Make IPv4 and IPv6 address addition and removal possible from
userspace app. But allow this only if CONFIG_NET_IF_USERSPACE_ACCESS
By default these operations are not allowed from userspace app.

Signed-off-by: Jukka Rissanen <[email protected]>

Author: jukkar

include/net/net_if.h

@@ -840,6 +840,16 @@ struct net_if_addr *net_if_ipv6_addr_lookup(const struct in6_addr *addr,
 struct net_if_addr *net_if_ipv6_addr_lookup_by_iface(struct net_if *iface,
 						     struct in6_addr *addr);
 
+/**
+ * @brief Check if this IPv6 address belongs to one of the interface indices.
+ *
+ * @param addr IPv6 address
+ *
+ * @return >0 if address was found in given network interface index,
+ * all other values mean address was not found
+ */
+__syscall int net_if_ipv6_addr_lookup_by_index(const struct in6_addr *addr);
+
 /**
  * @brief Add a IPv6 address to an interface
  *
@@ -855,6 +865,21 @@ struct net_if_addr *net_if_ipv6_addr_add(struct net_if *iface,
 					 enum net_addr_type addr_type,
 					 u32_t vlifetime);
 
+/**
+ * @brief Add a IPv6 address to an interface by index
+ *
+ * @param index Network interface index
+ * @param addr IPv6 address
+ * @param addr_type IPv6 address type
+ * @param vlifetime Validity time for this address
+ *
+ * @return True if ok, false if address could not be added
+ */
+__syscall bool net_if_ipv6_addr_add_by_index(int index,
+					     struct in6_addr *addr,
+					     enum net_addr_type addr_type,
+					     u32_t vlifetime);
+
 /**
  * @brief Update validity lifetime time of an IPv6 address.
  *
@@ -874,6 +899,16 @@ void net_if_ipv6_addr_update_lifetime(struct net_if_addr *ifaddr,
  */
 bool net_if_ipv6_addr_rm(struct net_if *iface, const struct in6_addr *addr);
 
+/**
+ * @brief Remove an IPv6 address from an interface by index
+ *
+ * @param index Network interface index
+ * @param addr IPv6 address
+ *
+ * @return True if successfully removed, false otherwise
+ */
+__syscall bool net_if_ipv6_addr_rm_by_index(int index,
+					    const struct in6_addr *addr);
 
 /**
  * @brief Add a IPv6 multicast address to an interface
@@ -1443,6 +1478,42 @@ struct net_if_addr *net_if_ipv4_addr_add(struct net_if *iface,
  */
 bool net_if_ipv4_addr_rm(struct net_if *iface,  struct in_addr *addr);
 
+/**
+ * @brief Check if this IPv4 address belongs to one of the interface indices.
+ *
+ * @param addr IPv4 address
+ *
+ * @return >0 if address was found in given network interface index,
+ * all other values mean address was not found
+ */
+__syscall int net_if_ipv4_addr_lookup_by_index(const struct in_addr *addr);
+
+/**
+ * @brief Add a IPv4 address to an interface by network interface index
+ *
+ * @param index Network interface index
+ * @param addr IPv4 address
+ * @param addr_type IPv4 address type
+ * @param vlifetime Validity time for this address
+ *
+ * @return True if ok, false if the address could not be added
+ */
+__syscall bool net_if_ipv4_addr_add_by_index(int index,
+					     struct in_addr *addr,
+					     enum net_addr_type addr_type,
+					     u32_t vlifetime);
+
+/**
+ * @brief Remove a IPv4 address from an interface by interface index
+ *
+ * @param index Network interface index
+ * @param addr IPv4 address
+ *
+ * @return True if successfully removed, false otherwise
+ */
+__syscall bool net_if_ipv4_addr_rm_by_index(int index,
+					    const struct in_addr *addr);
+
 /**
  * @brief Add a IPv4 multicast address to an interface
  *
@@ -2026,6 +2097,8 @@ struct net_if_api {
 }
 #endif
 
+#include <syscalls/net_if.h>
+
 /**
  * @}
  */

subsys/net/ip/Kconfig

@@ -492,6 +492,14 @@ config NET_HEADERS_ALWAYS_CONTIGUOUS
 	  NET_BUF_FIXED_DATA_SIZE enabled and NET_BUF_DATA_SIZE of 128 for
 	  instance.
 
+config NET_IF_USERSPACE_ACCESS
+	bool "Allow userspace app to manipulate network interface"
+	depends on USERSPACE
+	help
+	  Only enable this if you want a userspace application to manipulate
+	  network interface. Currently this is limited to add or remove
+	  IP addresses. By default this is not allowed.
+
 choice
 	prompt "Default Network Interface"
 	default NET_DEFAULT_IF_FIRST

subsys/net/ip/net_if.c

@@ -10,6 +10,7 @@ LOG_MODULE_REGISTER(net_if, CONFIG_NET_IF_LOG_LEVEL);
 #include <init.h>
 #include <kernel.h>
 #include <linker/sections.h>
+#include <syscall_handler.h>
 #include <stdlib.h>
 #include <string.h>
 #include <net/net_core.h>
@@ -751,6 +752,30 @@ struct net_if_addr *net_if_ipv6_addr_lookup_by_iface(struct net_if *iface,
 	return NULL;
 }
 
+int z_impl_net_if_ipv6_addr_lookup_by_index(const struct in6_addr *addr)
+{
+	struct net_if *iface = NULL;
+	struct net_if_addr *if_addr;
+
+	if_addr = net_if_ipv6_addr_lookup(addr, &iface);
+	if (!if_addr) {
+		return 0;
+	}
+
+	return net_if_get_by_iface(iface);
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv6_addr_lookup_by_index, addr)
+{
+	struct in6_addr addr_v6;
+
+	Z_OOPS(z_user_from_copy(&addr_v6, (void *)addr, sizeof(addr_v6)));
+
+	return z_impl_net_if_ipv6_addr_lookup_by_index(&addr_v6);
+}
+#endif
+
 #if defined(CONFIG_NET_IPV6)
 static bool check_timeout(u32_t start, s32_t timeout, u32_t counter,
 			  u32_t current_time)
@@ -1087,6 +1112,69 @@ bool net_if_ipv6_addr_rm(struct net_if *iface, const struct in6_addr *addr)
 	return false;
 }
 
+bool z_impl_net_if_ipv6_addr_add_by_index(int index,
+					  struct in6_addr *addr,
+					  enum net_addr_type addr_type,
+					  u32_t vlifetime)
+{
+	struct net_if *iface;
+
+	iface = net_if_get_by_index(index);
+	if (!iface) {
+		return false;
+	}
+
+	return net_if_ipv6_addr_add(iface, addr, addr_type, vlifetime) ?
+		true : false;
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv6_addr_add_by_index, index, addr, addr_type,
+		  vlifetime)
+{
+#if defined(CONFIG_NET_IF_USERSPACE_ACCESS)
+	struct in6_addr addr_v6;
+
+	Z_OOPS(z_user_from_copy(&addr_v6, (void *)addr, sizeof(addr_v6)));
+
+	return z_impl_net_if_ipv6_addr_add_by_index(index,
+						    &addr_v6,
+						    addr_type,
+						    vlifetime);
+#else
+	return false;
+#endif /* CONFIG_NET_IF_USERSPACE_ACCESS */
+}
+#endif /* CONFIG_USERSPACE */
+
+bool z_impl_net_if_ipv6_addr_rm_by_index(int index,
+					 const struct in6_addr *addr)
+{
+	struct net_if *iface;
+
+	iface = net_if_get_by_index(index);
+	if (!iface) {
+		return false;
+	}
+
+	return net_if_ipv6_addr_rm(iface, addr);
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv6_addr_rm_by_index, index, addr)
+{
+#if defined(CONFIG_NET_IF_USERSPACE_ACCESS)
+	struct in6_addr addr_v6;
+
+	Z_OOPS(z_user_from_copy(&addr_v6, (void *)addr, sizeof(addr_v6)));
+
+	return z_impl_net_if_ipv6_addr_rm_by_index(index, &addr_v6);
+#else
+	return false;
+#endif /* CONFIG_NET_IF_USERSPACE_ACCESS */
+}
+#endif /* CONFIG_USERSPACE */
+
 struct net_if_mcast_addr *net_if_ipv6_maddr_add(struct net_if *iface,
 						const struct in6_addr *addr)
 {
@@ -2485,6 +2573,30 @@ struct net_if_addr *net_if_ipv4_addr_lookup(const struct in_addr *addr,
 	return NULL;
 }
 
+int z_impl_net_if_ipv4_addr_lookup_by_index(const struct in_addr *addr)
+{
+	struct net_if_addr *if_addr;
+	struct net_if *iface = NULL;
+
+	if_addr = net_if_ipv4_addr_lookup(addr, &iface);
+	if (!if_addr) {
+		return 0;
+	}
+
+	return net_if_get_by_iface(iface);
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv4_addr_lookup_by_index, addr)
+{
+	struct in_addr addr_v4;
+
+	Z_OOPS(z_user_from_copy(&addr_v4, (void *)addr, sizeof(addr_v4)));
+
+	return z_impl_net_if_ipv4_addr_lookup_by_index(&addr_v4);
+}
+#endif
+
 #if defined(CONFIG_NET_IPV4)
 static struct net_if_addr *ipv4_addr_find(struct net_if *iface,
 					  struct in_addr *addr)
@@ -2609,6 +2721,70 @@ bool net_if_ipv4_addr_rm(struct net_if *iface, struct in_addr *addr)
 	return false;
 }
 
+bool z_impl_net_if_ipv4_addr_add_by_index(int index,
+					  struct in_addr *addr,
+					  enum net_addr_type addr_type,
+					  u32_t vlifetime)
+{
+	struct net_if *iface;
+	struct net_if_addr *if_addr;
+
+	iface = net_if_get_by_index(index);
+	if (!iface) {
+		return false;
+	}
+
+	if_addr = net_if_ipv4_addr_add(iface, addr, addr_type, vlifetime);
+	return if_addr ? true : false;
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv4_addr_add_by_index, index, addr, addr_type,
+		  vlifetime)
+{
+#if defined(CONFIG_NET_IF_USERSPACE_ACCESS)
+	struct in_addr addr_v4;
+
+	Z_OOPS(z_user_from_copy(&addr_v4, (void *)addr, sizeof(addr_v4)));
+
+	return z_impl_net_if_ipv4_addr_add_by_index(index,
+						    &addr_v4,
+						    addr_type,
+						    vlifetime);
+#else
+	return false;
+#endif /* CONFIG_NET_IF_USERSPACE_ACCESS */
+}
+#endif /* CONFIG_USERSPACE */
+
+bool z_impl_net_if_ipv4_addr_rm_by_index(int index,
+					 const struct in_addr *addr)
+{
+	struct net_if *iface;
+
+	iface = net_if_get_by_index(index);
+	if (!iface) {
+		return false;
+	}
+
+	return net_if_ipv4_addr_rm(iface, addr);
+}
+
+#ifdef CONFIG_USERSPACE
+Z_SYSCALL_HANDLER(net_if_ipv4_addr_rm_by_index, index, addr)
+{
+#if defined(CONFIG_NET_IF_USERSPACE_ACCESS)
+	struct in_addr addr_v4;
+
+	Z_OOPS(z_user_from_copy(&addr_v4, (void *)addr, sizeof(addr_v4)));
+
+	return (uint32_t)z_impl_net_if_ipv4_addr_rm_by_index(index, &addr_v4);
+#else
+	return false;
+#endif /* CONFIG_NET_IF_USERSPACE_ACCESS */
+}
+#endif /* CONFIG_USERSPACE */
+
 #if defined(CONFIG_NET_IPV4)
 static struct net_if_mcast_addr *ipv4_maddr_find(struct net_if *iface,
 						 bool is_used,