static void multi_link_modify_link(const struct nlmsghdr *nlh,
uint32_t probe_pipe, uint8_t unique){
struct ifinfomsg *ifi = mnl_nlmsg_get_payload(nlh);
struct nlattr *tb[IFLA_MAX + 1] = {};
uint8_t iface_state = 0;
struct multi_link_info *li = NULL;
struct multi_link_info_static *li_static = NULL;
pthread_attr_t detach_attr;
uint8_t wireless_mode = 0;
uint8_t *if_name;
mnl_attr_parse(nlh, sizeof(*ifi), multi_link_fill_rtattr, tb);
if (!tb[IFLA_IFNAME]) {
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Missing interface name\n");
return;
}
if_name = (uint8_t*) mnl_attr_get_str(tb[IFLA_IFNAME]);
if (!strncmp(if_name, "veth", 4) ||
ifi->ifi_type == ARPHRD_VOID ||
(ifi->ifi_type == ARPHRD_NONE && strncmp(if_name,"wwan", 4)) ||
ifi->ifi_type == ARPHRD_TUNNEL ||
ifi->ifi_flags & IFF_LOOPBACK)
return;
if(tb[IFLA_OPERSTATE]){
iface_state = mnl_attr_get_u8(tb[IFLA_OPERSTATE]);
/* Check linux/Documentation/networking/operstates.txt. IFF_RUNNING
* wraps both UP and UNKNOWN*/
if (ifi->ifi_flags & IFF_RUNNING){
//IF_OPER_UP == 6, defined in linux/if.h, chaos with includes
//if(iface_state == 6){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Interface %s (%u) is RUNNING, "
"length %u\n", if_name, ifi->ifi_index,
multi_link_num_links);
if((wireless_mode = multi_link_check_wlan_mode(if_name)))
if(wireless_mode == 6){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Interface %s is monitor, "
"ignoring\n", if_name);
return;
}
LIST_FIND_CUSTOM(li, &multi_link_links_2, next, &(ifi->ifi_index),
multi_cmp_ifidx);
if(li != NULL){
if(li->state == LINK_UP_STATIC_IFF){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Interface %s (idx %u) has "
"gone from UP to RUNNING\n", if_name, ifi->ifi_index);
li->state = GOT_IP_STATIC;
} else
MULTI_DEBUG_PRINT_SYSLOG(stderr,"Interface %s (idx %u) has "
"already been seen. Ignoring event\n", if_name,
ifi->ifi_index);
return;
}
if(multi_link_num_links < MAX_NUM_LINKS){
TAILQ_FIND_CUSTOM(li_static, &multi_shared_static_links,
list_ptr, if_name, multi_cmp_devname);
if(li_static != NULL){
if(li_static->proto == PROTO_IGNORE){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Ignoring %s\n", if_name);
return;
} else
li = multi_link_create_new_link(if_name,
li_static->metric);
} else {
/* Allocate a new link, add to list and start DHCP */
li = multi_link_create_new_link(if_name, 0);
}
if (!li) {
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Could not create link\n");
return;
}
//Insert link into link list
LIST_INSERT_HEAD(&multi_link_links_2, li, next);
++multi_link_num_links;
/* Add as a case here! The check for point to point */
if(li_static != NULL && li_static->proto == PROTO_STATIC){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Link %s found in static list\n",
if_name);
li->state = GOT_IP_STATIC;
li->cfg = li_static->cfg_static;
} else if (ifi->ifi_type == ARPHRD_PPP){
/* PPP will be dealt with separatley, since they get the IP
* remotely by themself */
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Link %s (%u) is PPP! state "
"%u %u\n", if_name, ifi->ifi_index, iface_state,
IFF_RUNNING);
li->state = LINK_DOWN_PPP;
multi_link_get_iface_info(li);
if(li->state != GOT_IP_PPP){
//Need to treat this in a special way! Remove li, keep
//li and have some sort of timeout?
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Could not get info for PPP "
"link %u (first look)!\n", ifi->ifi_index);
} else {
//Clean the information that is automatically added to
//routing table
multi_link_remove_ppp(li);
}
} else if(wireless_mode){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Link %s is wlan access point\n",
if_name);
li->state = LINK_DOWN_AP;
multi_link_get_iface_info(li);
//Remove the automatic route
multi_link_remove_ap(li);
} else {
pthread_attr_init(&detach_attr);
pthread_attr_setdetachstate(&detach_attr,
PTHREAD_CREATE_DETACHED);
pthread_create(&(li->dhcp_thread), &detach_attr,
multi_dhcp_main, (void *) li);
}
} else
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Limit reached, cannot add more links\n");
} else if(ifi->ifi_flags & IFF_UP){ //Might replace with IF_OPER_DOWN
//Check if interface has already been seen
LIST_FIND_CUSTOM(li, &multi_link_links_2, next, &(ifi->ifi_index),
multi_cmp_ifidx);
//Interface is already seen as UP, so clean up, no matter if static
//or not. Static is a special case: remove routes, li from list
//and free li
if(li != NULL){
//Need a generic cleanup, move the next "else" into a separate
//function
MULTI_DEBUG_PRINT_SYSLOG(stderr,"Interface %s (idx %u) has already "
"been seen as UP, will clean\n", if_name, ifi->ifi_index);
multi_link_delete_link(li, probe_pipe);
return;
}
//Check if interface is in static list
TAILQ_FIND_CUSTOM(li_static, &multi_shared_static_links, list_ptr,
if_name, multi_cmp_devname);
if(li_static != NULL && li_static->proto == PROTO_STATIC){
//Allocate a new link
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Link %s is UP\n", if_name);
li = multi_link_create_new_link(if_name, li_static->metric);
if (li == NULL) {
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Failed to create new link\n");
return;
}
li->state = GOT_IP_STATIC_UP;
li->cfg = li_static->cfg_static;
LIST_INSERT_HEAD(&multi_link_links_2, li, next);
++multi_link_num_links;
}
} else {
uint32_t dev_idx = ifi->ifi_index;
LIST_FIND_CUSTOM(li, &multi_link_links_2, next, &dev_idx,
multi_cmp_ifidx);
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Interface %s (index %u) is down, "
"length %u\n", if_name, ifi->ifi_index,
multi_link_num_links);
if(li == NULL){
MULTI_DEBUG_PRINT_SYSLOG(stderr, "Could not find %s (index %u), "
"length %u\n", if_name, ifi->ifi_index,
multi_link_num_links);
} else{
multi_link_delete_link(li, probe_pipe);
}
}
}
}
void multi_test_visible_loop(struct multi_config *mc){
uint8_t buf[MAX_BUFSIZE];
int32_t retval;
int32_t i;
int32_t netlink_sock = 0;
uint32_t ifi_idx = 0;
struct iface *ni = NULL;
/* Needed to create the netlink messages */
struct sockaddr_nl src_addr, dest_addr;
struct iovec iov;
struct msghdr msg;
/* Select is used for easier timeouts */
fd_set copy, master;
int32_t fdmax;
struct timeval tv;
memset(buf, 0, MAX_BUFSIZE);
/* Initialise list */
LIST_INIT(&iface_list);
/* Define a private constant later! Needs to be set in netlink.h so that the
* kernel will allow the socket to be created! */
if((netlink_sock = socket(PF_NETLINK, SOCK_RAW, NETLINK_GENERIC)) < 0){
perror("Could not create netlink socket: ");
exit(EXIT_FAILURE);
}
/* These are both constant! */
memset(&src_addr, 0, sizeof(src_addr));
memset(&dest_addr, 0, sizeof(dest_addr));
memset(&msg, 0, sizeof(msg));
src_addr.nl_family = AF_NETLINK;
//If PID is set to zero, then the kernel assigns the unique value
src_addr.nl_pid = 0;
//This is the source, it only multicasts, so it does not have to be
//member of any groups!
src_addr.nl_groups = 0;
if(bind(netlink_sock, (struct sockaddr *) &src_addr, sizeof(src_addr)) < 0){
perror("Could not bind netlink socket: ");
exit(EXIT_FAILURE);
}
dest_addr.nl_family = AF_NETLINK;
dest_addr.nl_pid = 0;
dest_addr.nl_groups = 1;
MULTI_DEBUG_PRINT(stderr, "Multi manager is ready! Netlink socket %d\n",
netlink_sock);
MULTI_DEBUG_PRINT(stderr, "M S\n");
//Look at the Wikipedia site for iovec and man(7) netlink for examples on
//how to properly parse netlink and have multiple iovec-entries
msg.msg_name = (void *) &dest_addr; //This is the message's destination
msg.msg_namelen = sizeof(dest_addr);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
//Initialise everything related to select
FD_ZERO(&master);
FD_ZERO(©);
FD_SET(mc->socket_pipe[0], &master);
fdmax = mc->socket_pipe[0];
tv.tv_sec = 30;
tv.tv_usec = 0;
pthread_t multi_thread = multi_start(mc);
while(1){
copy = master;
retval = select(fdmax + 1, ©, NULL, NULL, &tv);
//Repeat every UP message
if(retval == 0){
for(ni = iface_list.lh_first; ni != NULL; ni = ni->next.le_next){
printf("Hei\n");
iov.iov_base = (void *) ni->nlmsg;
iov.iov_len = ni->nlmsg->nlmsg_len;
sendmsg(netlink_sock, &msg, 0);
}
tv.tv_sec = 30;
tv.tv_usec = 0;
continue;
}
memset(buf, 0, MAX_BUFSIZE);
//Sufficient to just memcpy this one and broadcast the netlink message
retval = read(mc->socket_pipe[0], buf, MAX_BUFSIZE);
if(retval == -1)
perror("Failed to read from pipe");
else {
memcpy(&ifi_idx, (buf+1), sizeof(uint32_t));
//This check needs to be performed irrespective of if link goes up
//or down.
LIST_FIND_CUSTOM(ni, &iface_list, next, &ifi_idx,
multi_mc_cmp_ifi);
if(buf[0] == LINK_UP){
//Sanity check. If the interface is already found, ignore the
//announcement from MULTI.
if(ni)
continue;
//Create a new iface, buffer the up message and add to list
ni = (struct iface*) malloc(sizeof(struct iface));
ni->ifi_idx = ifi_idx;
ni->nlmsg = (struct nlmsghdr *) malloc(NLMSG_SPACE(retval));
memset(ni->nlmsg, 0, NLMSG_SPACE(retval));
ni->nlmsg->nlmsg_pid = getpid();
ni->nlmsg->nlmsg_flags = 0;
ni->nlmsg->nlmsg_len = NLMSG_SPACE(retval);
memcpy(NLMSG_DATA(ni->nlmsg), buf, retval);
LIST_INSERT_HEAD(&iface_list, ni, next);
//Adjust the base pointer of the message and broadcast message
iov.iov_base = (void *) ni->nlmsg;
iov.iov_len = ni->nlmsg->nlmsg_len;
retval = sendmsg(netlink_sock, &msg, 0);
MULTI_DEBUG_PRINT(stderr,"Broadcasted %d bytes about an UP "
"change in network state\n", retval);
} else {
if(ni){
//Forward message from MULTI
ni->nlmsg->nlmsg_len = NLMSG_SPACE(retval);
memcpy(NLMSG_DATA(ni->nlmsg), buf, retval);
iov.iov_base = (void *) ni->nlmsg;
iov.iov_len = ni->nlmsg->nlmsg_len;
retval = sendmsg(netlink_sock, &msg, 0);
MULTI_DEBUG_PRINT(stderr,"Broadcasted %d bytes about a "
"DOWN change in network state\n", retval);
LIST_REMOVE(ni, next);
free(ni);
}
}
}
}
}
