shared,dhcp: add _nm_utils_ip4_get_default_prefix0() helper

3 files changed, 23 insertions, 52 deletions

diff --git a/shared/nm-glib-aux/nm-shared-utils.c b/shared/nm-glib-aux/nm-shared-utils.c
index 492a3d5098..3215a33b5b 100644
--- a/shared/nm-glib-aux/nm-shared-utils.c
+++ b/shared/nm-glib-aux/nm-shared-utils.c
@@ -786,27 +786,27 @@ nm_utils_ip6_address_same_prefix_cmp(const struct in6_addr *addr_a,
     return 0;
 }
 
-/**
- * _nm_utils_ip4_get_default_prefix:
- * @ip: an IPv4 address (in network byte order)
- *
- * When the Internet was originally set up, various ranges of IP addresses were
- * segmented into three network classes: A, B, and C.  This function will return
- * a prefix that is associated with the IP address specified defining where it
- * falls in the predefined classes.
- *
- * Returns: the default class prefix for the given IP
- **/
-/* The function is originally from ipcalc.c of Red Hat's initscripts. */
+/*****************************************************************************/
+
 guint32
-_nm_utils_ip4_get_default_prefix(guint32 ip)
+_nm_utils_ip4_get_default_prefix0(in_addr_t ip)
 {
-    if (((ntohl(ip) & 0xFF000000) >> 24) <= 127)
-        return 8; /* Class A - 255.0.0.0 */
-    else if (((ntohl(ip) & 0xFF000000) >> 24) <= 191)
-        return 16; /* Class B - 255.255.0.0 */
+    /* The function is originally from ipcalc.c of Red Hat's initscripts. */
+    switch (ntohl(ip) >> 24) {
+    case 0 ... 127:
+        return 8; /* Class A */
+    case 128 ... 191:
+        return 16; /* Class B */
+    case 192 ... 223:
+        return 24; /* Class C */
+    }
+    return 0;
+}
 
-    return 24; /* Class C - 255.255.255.0 */
+guint32
+_nm_utils_ip4_get_default_prefix(in_addr_t ip)
+{
+    return _nm_utils_ip4_get_default_prefix0(ip) ?: 24;
 }
 
 gboolean
diff --git a/shared/nm-glib-aux/nm-shared-utils.h b/shared/nm-glib-aux/nm-shared-utils.h
index c432b125b6..7d330458c1 100644
--- a/shared/nm-glib-aux/nm-shared-utils.h
+++ b/shared/nm-glib-aux/nm-shared-utils.h
@@ -699,7 +699,8 @@ nm_utils_escaped_tokens_options_escape_val(const char *val, char **out_to_free)
 /*****************************************************************************/
 
 guint32 _nm_utils_ip4_prefix_to_netmask(guint32 prefix);
-guint32 _nm_utils_ip4_get_default_prefix(guint32 ip);
+guint32 _nm_utils_ip4_get_default_prefix0(in_addr_t ip);
+guint32 _nm_utils_ip4_get_default_prefix(in_addr_t ip);
 
 gconstpointer
 nm_utils_ipx_address_clear_host_address(int family, gpointer dst, gconstpointer src, guint8 plen);
diff --git a/src/core/dhcp/nm-dhcp-nettools.c b/src/core/dhcp/nm-dhcp-nettools.c
index 37f812c9fb..1381de47ae 100644
--- a/src/core/dhcp/nm-dhcp-nettools.c
+++ b/src/core/dhcp/nm-dhcp-nettools.c
@@ -86,27 +86,7 @@ set_error_nettools(GError **error, int r, const char *message)
 
 #define DHCP_MAX_FQDN_LENGTH 255
 
-enum {
-    NM_IN_ADDR_CLASS_A,
-    NM_IN_ADDR_CLASS_B,
-    NM_IN_ADDR_CLASS_C,
-    NM_IN_ADDR_CLASS_INVALID,
-};
-
-static int
-in_addr_class(in_addr_t addr)
-{
-    switch (ntohl(addr) >> 24) {
-    case 0 ... 127:
-        return NM_IN_ADDR_CLASS_A;
-    case 128 ... 191:
-        return NM_IN_ADDR_CLASS_B;
-    case 192 ... 223:
-        return NM_IN_ADDR_CLASS_C;
-    default:
-        return NM_IN_ADDR_CLASS_INVALID;
-    }
-}
+/*****************************************************************************/
 
 static gboolean
 lease_option_consume(uint8_t **datap, size_t *n_datap, void *out, size_t n_out)
@@ -158,19 +138,9 @@ lease_option_consume_route(uint8_t ** datap,
         if (!lease_option_consume_in_addr(&data, &n_data, &dest))
             return FALSE;
 
-        switch (in_addr_class(dest)) {
-        case NM_IN_ADDR_CLASS_A:
-            plen = 8;
-            break;
-        case NM_IN_ADDR_CLASS_B:
-            plen = 16;
-            break;
-        case NM_IN_ADDR_CLASS_C:
-            plen = 24;
-            break;
-        case NM_IN_ADDR_CLASS_INVALID:
+        plen = _nm_utils_ip4_get_default_prefix0(dest);
+        if (plen == 0)
             return FALSE;
-        }
     }
 
     dest = nm_utils_ip4_address_clear_host_address(dest, plen);