/* function: interface_poll
* polls the uplink network interface for address changes
* tunnel - tun device data
*/
void interface_poll(const struct tun_data *tunnel) {
union anyip *interface_ip;
interface_ip = getinterface_ip(Global_Clatd_Config.default_pdp_interface, AF_INET6);
if(!interface_ip) {
logmsg(ANDROID_LOG_WARN,"unable to find an ipv6 ip on interface %s",Global_Clatd_Config.default_pdp_interface);
return;
}
config_generate_local_ipv6_subnet(&interface_ip->ip6);
if(!IN6_ARE_ADDR_EQUAL(&interface_ip->ip6, &Global_Clatd_Config.ipv6_local_subnet)) {
char from_addr[INET6_ADDRSTRLEN], to_addr[INET6_ADDRSTRLEN];
inet_ntop(AF_INET6, &Global_Clatd_Config.ipv6_local_subnet, from_addr, sizeof(from_addr));
inet_ntop(AF_INET6, &interface_ip->ip6, to_addr, sizeof(to_addr));
logmsg(ANDROID_LOG_WARN, "clat subnet changed from %s to %s", from_addr, to_addr);
// remove old route
deconfigure_tun_ipv6(tunnel);
// add new route, start translating packets to the new prefix
memcpy(&Global_Clatd_Config.ipv6_local_subnet, &interface_ip->ip6, sizeof(struct in6_addr));
configure_tun_ipv6(tunnel);
}
free(interface_ip);
}
/* function: subnet_from_interface
* finds the ipv6 subnet configured on the specified interface
* root - parsed configuration
* interface - network interface name
*/
int subnet_from_interface(cnode *root, const char *interface) {
union anyip *interface_ip;
if(!config_item_ip6(root, "ipv6_host_id", "::200:5E10:0:0", &Global_Clatd_Config.ipv6_host_id))
return 0;
interface_ip = getinterface_ip(interface, AF_INET6);
if(!interface_ip) {
logmsg(ANDROID_LOG_FATAL,"unable to find an ipv6 ip on interface %s",interface);
return 0;
}
memcpy(&Global_Clatd_Config.ipv6_local_subnet, &interface_ip->ip6, sizeof(struct in6_addr));
free(interface_ip);
config_generate_local_ipv6_subnet(&Global_Clatd_Config.ipv6_local_subnet);
return 1;
}
/* function: subnet_from_interface
* finds the ipv6 subnet configured on the specified interface
* root - parsed configuration
* interface - network interface name
*/
int subnet_from_interface(cnode *root, const char *interface) {
union anyip *interface_ip;
char prop_name[PROPERTY_KEY_MAX];
char prop_value[PROPERTY_VALUE_MAX];
int cnt = 10;
if(!config_item_ip6(root, "ipv6_host_id", "::200:5E10:0:0", &Global_Clatd_Config.ipv6_host_id))
return 0;
logmsg(ANDROID_LOG_INFO, "before get net.ipv6.prefix");
snprintf(prop_name, sizeof(prop_name), "net.ipv6.%s.prefix", interface);
while(cnt-->0)
{
property_get(prop_name, prop_value, NULL);
if (strcmp(prop_value, ""))
{
break;
}
sleep(1);
}
logmsg(ANDROID_LOG_INFO, "after get net.ipv6.prefix");
interface_ip = getinterface_ip(interface, AF_INET6);
if(!interface_ip) {
logmsg(ANDROID_LOG_FATAL,"unable to find an ipv6 ip on interface %s",interface);
return 0;
}
memcpy(&Global_Clatd_Config.ipv6_local_subnet, &interface_ip->ip6, sizeof(struct in6_addr));
free(interface_ip);
config_generate_local_ipv6_subnet(&Global_Clatd_Config.ipv6_local_subnet);
return 1;
}
