libexport.a: Refactor init_netmask()

Instead of a single function that can handle both AF_INET and AF_INET6
addresses, two separate functions might be cleaner.

The original plan was to keep code redundancy at a minimum, but the
resulting code was cumbersome at best.  I think I've traded a little
extra code for something that will be much easier to read, understand,
and maintain.

I've also eliminated the "#if / #endif" instances inside the functions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/support/export/client.c b/support/export/client.c
index c74961e56f0e6eb0bcb1eefbafc53689ce29dfd7..dbfc2b1449bfe251a74f5e8d08026e5e2ba63d40 100644 (file)
--- a/support/export/client.c
+++ b/support/export/client.c
@@ -60,86 +60,111 @@ client_free(nfs_client *clp)
 }
 
 static int
-init_netmask(nfs_client *clp, const char *slash, const sa_family_t family)
+init_netmask4(nfs_client *clp, const char *slash)
 {
        struct sockaddr_in sin = {
                .sin_family             = AF_INET,
        };
-       unsigned long prefixlen;
        uint32_t shift;
-#ifdef IPV6_SUPPORTED
-       struct sockaddr_in6 sin6 = {
-               .sin6_family            = AF_INET6,
-       };
-       int i;
-#endif
 
-       /* No slash present; assume netmask is all ones */
-       if (slash == NULL) {
-               switch (family) {
-               case AF_INET:
-                       prefixlen = 32;
-                       break;
-#ifdef IPV6_SUPPORTED
-               case AF_INET6:
-                       prefixlen = 128;
-                       break;
-#endif
-               default:
-                       goto out_badfamily;
-               }
-       } else {
-               char *endptr;
+       /*
+        * Decide what kind of netmask was specified.  If there's
+        * no '/' present, assume the netmask is all ones.  If
+        * there is a '/' and at least one '.', look for a spelled-
+        * out netmask.  Otherwise, assume it was a prefixlen.
+        */
+       if (slash == NULL)
+               shift = 0;
+       else {
+               unsigned long prefixlen;
 
-               /* A spelled out netmask address, perhaps? */
                if (strchr(slash + 1, '.') != NULL) {
                        if (inet_pton(AF_INET, slash + 1,
                                                &sin.sin_addr.s_addr) == 0)
                                goto out_badmask;
                        set_addrlist_in(clp, 1, &sin);
                        return 1;
+               } else {
+                       char *endptr;
+
+                       prefixlen = strtoul(slash + 1, &endptr, 10);
+                       if (*endptr != '\0' && prefixlen != ULONG_MAX &&
+                           errno != ERANGE)
+                               goto out_badprefix;
                }
+               if (prefixlen > 32)
+                       goto out_badprefix;
+               shift = 32 - (uint32_t)prefixlen;
+       }
+
+       /*
+        * Now construct the full netmask bitmask in a sockaddr_in,
+        * and plant it in the nfs_client record.
+        */
+       sin.sin_addr.s_addr = htonl((uint32_t)~0 << shift);
+       set_addrlist_in(clp, 1, &sin);
+
+       return 1;
+
+out_badmask:
+       xlog(L_ERROR, "Invalid netmask `%s' for %s", slash + 1, clp->m_hostname);
+       return 0;
+
+out_badprefix:
+       xlog(L_ERROR, "Invalid prefix `%s' for %s", slash + 1, clp->m_hostname);
+       return 0;
+}
+
 #ifdef IPV6_SUPPORTED
-               if (strchr(slash + 1, ':')) {
+static int
+init_netmask6(nfs_client *clp, const char *slash)
+{
+       struct sockaddr_in6 sin6 = {
+               .sin6_family            = AF_INET6,
+       };
+       unsigned long prefixlen;
+       uint32_t shift;
+       int i;
+
+       /*
+        * Decide what kind of netmask was specified.  If there's
+        * no '/' present, assume the netmask is all ones.  If
+        * there is a '/' and at least one ':', look for a spelled-
+        * out netmask.  Otherwise, assume it was a prefixlen.
+        */
+       if (slash == NULL)
+               prefixlen = 128;
+       else {
+               if (strchr(slash + 1, ':') != NULL) {
                        if (!inet_pton(AF_INET6, slash + 1, &sin6.sin6_addr))
                                goto out_badmask;
                        set_addrlist_in6(clp, 1, &sin6);
                        return 1;
-               }
-#endif
+               } else {
+                       char *endptr;
 
-               /* A prefixlen was given */
-               prefixlen = strtoul(slash + 1, &endptr, 10);
-               if (*endptr != '\0' && prefixlen != ULONG_MAX && errno != ERANGE)
+                       prefixlen = strtoul(slash + 1, &endptr, 10);
+                       if (*endptr != '\0' && prefixlen != ULONG_MAX &&
+                           errno != ERANGE)
+                               goto out_badprefix;
+               }
+               if (prefixlen > 128)
                        goto out_badprefix;
        }
 
-       switch (family) {
-       case AF_INET:
-               if (prefixlen > 32)
-                       goto out_badprefix;
-               shift = 32 - (uint32_t)prefixlen;
-               sin.sin_addr.s_addr = htonl((uint32_t)~0 << shift);
-               set_addrlist_in(clp, 1, &sin);
-               return 1;
-#ifdef IPV6_SUPPORTED
-       case AF_INET6:
-               if (prefixlen > 128)
-                       goto out_badprefix;
-               for (i = 0; prefixlen > 32; i++) {
-                       sin6.sin6_addr.s6_addr32[i] = 0xffffffff;
-                       prefixlen -= 32;
-               }
-               shift = 32 - (uint32_t)prefixlen;
-               sin6.sin6_addr.s6_addr32[i] = htonl((uint32_t)~0 << shift);
-               set_addrlist_in6(clp, 1, &sin6);
-               return 1;
-#endif
+       /*
+        * Now construct the full netmask bitmask in a sockaddr_in6,
+        * and plant it in the nfs_client record.
+        */
+       for (i = 0; prefixlen > 32; i++) {
+               sin6.sin6_addr.s6_addr32[i] = 0xffffffff;
+               prefixlen -= 32;
        }
+       shift = 32 - (uint32_t)prefixlen;
+       sin6.sin6_addr.s6_addr32[i] = htonl((uint32_t)~0 << shift);
+       set_addrlist_in6(clp, 1, &sin6);
 
-out_badfamily:
-       xlog(L_ERROR, "Unsupported address family for %s", clp->m_hostname);
-       return 0;
+       return 1;
 
 out_badmask:
        xlog(L_ERROR, "Invalid netmask `%s' for %s", slash + 1, clp->m_hostname);
@@ -149,12 +174,24 @@ out_badprefix:
        xlog(L_ERROR, "Invalid prefix `%s' for %s", slash + 1, clp->m_hostname);
        return 0;
 }
+#else  /* IPV6_SUPPORTED */
+static int
+init_netmask6(nfs_client *UNUSED(clp), const char *UNUSED(slash))
+{
+}
+#endif /* IPV6_SUPPORTED */
 
+/*
+ * Parse the network mask for M_SUBNETWORK type clients.
+ *
+ * Return TRUE if successful, or FALSE if some error occurred.
+ */
 static int
 init_subnetwork(nfs_client *clp)
 {
        struct addrinfo *ai;
        sa_family_t family;
+       int result = 0;
        char *slash;
 
        slash = strchr(clp->m_hostname, '/');
@@ -166,7 +203,7 @@ init_subnetwork(nfs_client *clp)
                ai = host_pton(clp->m_hostname);
        if (ai == NULL) {
                xlog(L_ERROR, "Invalid IP address %s", clp->m_hostname);
-               return false;
+               return result;
        }
 
        set_addrlist(clp, 0, ai->ai_addr);
@@ -174,7 +211,19 @@ init_subnetwork(nfs_client *clp)
 
        freeaddrinfo(ai);
 
-       return init_netmask(clp, slash, family);
+       switch (family) {
+       case AF_INET:
+               result = init_netmask4(clp, slash);
+               break;
+       case AF_INET6:
+               result = init_netmask6(clp, slash);
+               break;
+       default:
+               xlog(L_ERROR, "Unsupported address family for %s",
+                       clp->m_hostname);
+       }
+
+       return result;
 }
 
 static int