using aligned buffers for netlink

src/charon/plugins/kernel_netlink/kernel_netlink_ipsec.c

@@ -735,7 +735,7 @@ static status_t get_spi_internal(private_kernel_netlink_ipsec_t *this,
 		host_t *src, host_t *dst, u_int8_t proto, u_int32_t min, u_int32_t max,
 		u_int32_t reqid, u_int32_t *spi)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr, *out;
 	struct xfrm_userspi_info *userspi;
 	u_int32_t received_spi = 0;
@@ -858,7 +858,7 @@ static status_t add_sa(private_kernel_netlink_ipsec_t *this,
 					   ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi,
 					   bool encap, bool inbound)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	char *alg_name;
 	struct nlmsghdr *hdr;
 	struct xfrm_usersa_info *sa;
@@ -1081,7 +1081,7 @@ static status_t get_replay_state(private_kernel_netlink_ipsec_t *this,
 						  u_int32_t spi, protocol_id_t protocol, host_t *dst,
 						  struct xfrm_replay_state *replay)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr, *out = NULL;
 	struct xfrm_aevent_id *out_aevent = NULL, *aevent_id;
 	size_t len;
@@ -1168,7 +1168,7 @@ static status_t get_replay_state(private_kernel_netlink_ipsec_t *this,
 static status_t del_sa(private_kernel_netlink_ipsec_t *this, host_t *dst,
 					   u_int32_t spi, protocol_id_t protocol, u_int16_t cpi)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr;
 	struct xfrm_usersa_id *sa_id;
 	
@@ -1211,7 +1211,8 @@ static status_t update_sa(private_kernel_netlink_ipsec_t *this,
 						  host_t *new_src, host_t *new_dst,
 						  bool old_encap, bool new_encap)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE], *pos;
+	netlink_buf_t request;
+	u_char *pos;
 	struct nlmsghdr *hdr, *out = NULL;
 	struct xfrm_usersa_id *sa_id;
 	struct xfrm_usersa_info *out_sa = NULL, *sa;
@@ -1397,7 +1398,7 @@ static status_t add_policy(private_kernel_netlink_ipsec_t *this,
 	iterator_t *iterator;
 	policy_entry_t *current, *policy;
 	bool found = FALSE;
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct xfrm_userpolicy_info *policy_info;
 	struct nlmsghdr *hdr;
 	
@@ -1582,7 +1583,7 @@ static status_t query_policy(private_kernel_netlink_ipsec_t *this,
 							 traffic_selector_t *dst_ts,
 							 policy_dir_t direction, u_int32_t *use_time)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *out = NULL, *hdr;
 	struct xfrm_userpolicy_id *policy_id;
 	struct xfrm_userpolicy_info *policy = NULL;
@@ -1654,7 +1655,7 @@ static status_t del_policy(private_kernel_netlink_ipsec_t *this,
 {
 	policy_entry_t *current, policy, *to_delete = NULL;
 	route_entry_t *route;
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr;
 	struct xfrm_userpolicy_id *policy_id;
 	enumerator_t *enumerator;

src/charon/plugins/kernel_netlink/kernel_netlink_net.c

@@ -761,7 +761,7 @@ static bool addr_in_subnet(chunk_t addr, chunk_t net, int net_len)
 static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
 						 bool nexthop, host_t *candidate)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr, *out, *current;
 	struct rtmsg *msg;
 	chunk_t chunk;
@@ -948,7 +948,7 @@ static host_t* get_nexthop(private_kernel_netlink_net_t *this, host_t *dest)
 static status_t manage_ipaddr(private_kernel_netlink_net_t *this, int nlmsg_type,
 							  int flags, int if_index, host_t *ip)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr;
 	struct ifaddrmsg *msg;
 	chunk_t chunk;
@@ -1116,7 +1116,7 @@ static status_t manage_srcroute(private_kernel_netlink_net_t *this, int nlmsg_ty
 								int flags, chunk_t dst_net, u_int8_t prefixlen,
 								host_t *gateway, host_t *src_ip, char *if_name)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr;
 	struct rtmsg *msg;
 	int ifindex;
@@ -1196,7 +1196,7 @@ status_t del_route(private_kernel_netlink_net_t *this, chunk_t dst_net,
  */
 static status_t init_address_list(private_kernel_netlink_net_t *this)
 {
-	char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *out, *current, *in;
 	struct rtgenmsg *msg;
 	size_t len;
@@ -1288,7 +1288,7 @@ static status_t init_address_list(private_kernel_netlink_net_t *this)
 static status_t manage_rule(private_kernel_netlink_net_t *this, int nlmsg_type,
 							u_int32_t table, u_int32_t prio)
 {
-	unsigned char request[NETLINK_BUFFER_SIZE];
+	netlink_buf_t request;
 	struct nlmsghdr *hdr;
 	struct rtmsg *msg;
 	chunk_t chunk;

src/charon/plugins/kernel_netlink/kernel_netlink_shared.h

@@ -20,7 +20,15 @@
 
 #include <library.h>
 
-#define NETLINK_BUFFER_SIZE 1024
+#include <linux/rtnetlink.h>
+
+/**
+ * General purpose netlink buffer.
+ *
+ * 1024 byte is currently sufficient for all operations. Some platform
+ * require an enforced aligment to four bytes (e.g. ARM).
+ */
+typedef u_char netlink_buf_t[1024] __attribute__((aligned(RTA_ALIGNTO)));
 
 typedef struct netlink_socket_t netlink_socket_t;