Avoid extensive casting of sockaddr types in socket-default by using a union

Additionally fixes a strict-aliasing rule compiler warning with older gcc.

diff --git a/src/libcharon/plugins/socket_default/socket_default_socket.c b/src/libcharon/plugins/socket_default/socket_default_socket.c
index 51432c9607f11f6d45bdd2fe4e7fcb8e859bf2f0..2cf32b0c01e1eb2267f83f518d5da54d2e3c76d5 100644 (file)
--- a/src/libcharon/plugins/socket_default/socket_default_socket.c
+++ b/src/libcharon/plugins/socket_default/socket_default_socket.c
@@ -433,22 +433,24 @@ static int open_socket(private_socket_default_socket_t *this,
                                           int family, u_int16_t *port)
 {
        int on = TRUE;
-       struct sockaddr_storage addr;
+       union {
+               struct sockaddr sockaddr;
+               struct sockaddr_in sin;
+               struct sockaddr_in6 sin6;
+       } addr;
        socklen_t addrlen;
        u_int sol, pktinfo = 0;
        int skt;
 
        memset(&addr, 0, sizeof(addr));
-       addr.ss_family = family;
+       addr.sockaddr.sa_family = family;
        /* precalculate constants depending on address family */
        switch (family)
        {
                case AF_INET:
-               {
-                       struct sockaddr_in *sin = (struct sockaddr_in *)&addr;
-                       htoun32(&sin->sin_addr.s_addr, INADDR_ANY);
-                       htoun16(&sin->sin_port, *port);
-                       addrlen = sizeof(struct sockaddr_in);
+                       addr.sin.sin_addr.s_addr = htonl(INADDR_ANY);
+                       addr.sin.sin_port = htons(*port);
+                       addrlen = sizeof(addr.sin);
                        sol = SOL_IP;
 #ifdef IP_PKTINFO
                        pktinfo = IP_PKTINFO;
@@ -456,17 +458,13 @@ static int open_socket(private_socket_default_socket_t *this,
                        pktinfo = IP_RECVDSTADDR;
 #endif
                        break;
-               }
                case AF_INET6:
-               {
-                       struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr;
-                       memcpy(&sin6->sin6_addr, &in6addr_any, sizeof(in6addr_any));
-                       htoun16(&sin6->sin6_port, *port);
-                       addrlen = sizeof(struct sockaddr_in6);
+                       memcpy(&addr.sin6.sin6_addr, &in6addr_any, sizeof(in6addr_any));
+                       addr.sin6.sin6_port = htons(*port);
+                       addrlen = sizeof(addr.sin6);
                        sol = SOL_IPV6;
                        pktinfo = IPV6_RECVPKTINFO;
                        break;
-               }
                default:
                        return 0;
        }
@@ -485,7 +483,7 @@ static int open_socket(private_socket_default_socket_t *this,
        }
 
        /* bind the socket */
-       if (bind(skt, (struct sockaddr *)&addr, addrlen) < 0)
+       if (bind(skt, &addr.sockaddr, addrlen) < 0)
        {
                DBG1(DBG_NET, "unable to bind socket: %s", strerror(errno));
                close(skt);
@@ -495,7 +493,7 @@ static int open_socket(private_socket_default_socket_t *this,
        /* retrieve randomly allocated port if needed */
        if (*port == 0)
        {
-               if (getsockname(skt, (struct sockaddr *)&addr, &addrlen) < 0)
+               if (getsockname(skt, &addr.sockaddr, &addrlen) < 0)
                {
                        DBG1(DBG_NET, "unable to determine port: %s", strerror(errno));
                        close(skt);
@@ -504,17 +502,11 @@ static int open_socket(private_socket_default_socket_t *this,
                switch (family)
                {
                        case AF_INET:
-                       {
-                               struct sockaddr_in *sin = (struct sockaddr_in *)&addr;
-                               *port = untoh16(&sin->sin_port);
+                               *port = ntohs(addr.sin.sin_port);
                                break;
-                       }
                        case AF_INET6:
-                       {
-                               struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr;
-                               *port = untoh16(&sin6->sin6_port);
+                               *port = ntohs(addr.sin6.sin6_port);
                                break;
-                       }
                }
        }