utils.c: Add ip address validation

Do not allow configuring invalid IPv4/IPv6 addresses.
Curently if I configure LAN IP Address as 224.1.1.1, netifd will
configure it.
e.g.
uci set network.lan.ipaddr='224.1.1.1'
uci commit
/etc/init.d/network restart

Now ifconfig br-lan returns
br-lan    Link encap:Ethernet  HWaddr 00:03:7F:13:BA:17
          inet addr:224.1.1.1  Bcast:224.1.1.255  Mask:255.255.255.0
which is wrong.

If I use ifconfig eth1 224.1.1.1, I will get
ifconfig: SIOCSIFADDR: Invalid argument

it means ifconfig is working fine, whereas netifd not.
Proposed patch will test IPv4 address to make sure it is class A/B/C only.
Similarly IPv6 multicast addresses will not be allowed.

Signed-off-by: Naresh Kumar Mehta <naresh@codeaurora.org>

diff --git a/utils.c b/utils.c
index ba2695272ac9a1fac486ebdecc6f97544aaf54fb..e01b633c09e0143ebf98dbdb62ef77deecacaf73 100644 (file)
--- a/utils.c
+++ b/utils.c
@@ -119,6 +119,7 @@ int
 parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
 {
        char *astr = alloca(strlen(str) + 1);
+       int ret = 0;
 
        strcpy(astr, str);
        if (!split_netmask(astr, netmask, af == AF_INET6))
@@ -132,7 +133,23 @@ parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
                        return 0;
        }
 
-       return inet_pton(af, astr, addr);
+       ret = inet_pton(af, astr, addr);
+       if (ret > 0) {
+               if (af == AF_INET) {
+                       struct in_addr *ip4_addr = (struct in_addr *)addr;
+                       uint32_t host_addr = ntohl(ip4_addr->s_addr);
+
+                       if (IN_EXPERIMENTAL(host_addr)) {
+                               return 0;
+                       }
+               }
+               else if (af == AF_INET6) {
+                       if (IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) {
+                               return 0;
+                       }
+               }
+       }
+       return ret;
 }
 
 char *