diff options
| -rw-r--r-- | netlink-notify.c | 96 |
1 files changed, 82 insertions, 14 deletions
diff --git a/netlink-notify.c b/netlink-notify.c index 00b3a4d..55fcfea 100644 --- a/netlink-notify.c +++ b/netlink-notify.c @@ -44,9 +44,30 @@ #define CHECK_CONNECTED IFF_LOWER_UP +struct addresses_seen { + char *address; + unsigned char prefix; + struct addresses_seen *next; +}; + char *program; unsigned int maxinterface = 0; -NotifyNotification ** notification; +NotifyNotification ** notification = NULL; +struct addresses_seen *addresses_seen = NULL; + +/*** free_chain ***/ +void free_chain(struct addresses_seen *first) { + struct addresses_seen *addresses_seen = first->next; + + while (addresses_seen != NULL) { + struct addresses_seen *next = addresses_seen->next; + free(addresses_seen->address); + free(addresses_seen); + addresses_seen = next; + } + + first->next = NULL; +} /*** newstr_link ***/ char * newstr_link(char *text, char *interface, unsigned int flags) { @@ -59,13 +80,11 @@ char * newstr_link(char *text, char *interface, unsigned int flags) { } /*** newstr_addr ***/ -char * newstr_addr(char *text, char *interface, unsigned char family, void *ipaddr, unsigned char prefix) { +char * newstr_addr(char *text, char *interface, unsigned char family, char *ipaddr, unsigned char prefix) { char *notifystr; - char buf[64]; - inet_ntop(family, ipaddr, buf, sizeof(buf)); - notifystr = malloc(strlen(text) + strlen(interface) + strlen(buf)); - sprintf(notifystr, text, interface, family == AF_INET6 ? "IPv6" : "IP", buf, prefix); + notifystr = malloc(strlen(text) + strlen(interface) + strlen(ipaddr)); + sprintf(notifystr, text, interface, family == AF_INET6 ? "IPv6" : "IP", ipaddr, prefix); return notifystr; } @@ -160,20 +179,31 @@ static int msg_handler (struct sockaddr_nl *nl, struct nlmsghdr *msg) { struct rtattr *rth; int rtl; char name[IFNAMSIZ]; - NotifyNotification * address = NULL; + char buf[64]; + struct addresses_seen *next; + unsigned char seen; + NotifyNotification *address = NULL; ifa = (struct ifaddrmsg *) NLMSG_DATA (msg); ifi = (struct ifinfomsg *) NLMSG_DATA (msg); if_indextoname(ifi->ifi_index, name); - - /* make sure we have alloced memory for the struct array */ + + /* make sure we have alloced memory for NotifyNotification and addresses_seen struct array */ if (maxinterface < ifi->ifi_index) { - notification = realloc(notification, (ifi->ifi_index + 1) * sizeof(NotifyNotification)); - for(; maxinterface < ifi->ifi_index; maxinterface++) + notification = realloc(notification, (ifi->ifi_index + 1) * sizeof(size_t)); + addresses_seen = realloc(addresses_seen, (ifi->ifi_index + 1) * sizeof(struct addresses_seen)); + do { + maxinterface++; /* there is no interface with index 0, so this is safe */ notification[maxinterface] = NULL; + addresses_seen[maxinterface].next = NULL; + } while (maxinterface < ifi->ifi_index); } +#if DEBUG + printf("Interface %s, flags: %x, msg type: %d\n", name, ifa->ifa_flags, msg->nlmsg_type); +#endif + switch (msg->nlmsg_type) { /* just return for cases we want to ignore */ case RTM_NEWADDR: @@ -183,9 +213,40 @@ static int msg_handler (struct sockaddr_nl *nl, struct nlmsghdr *msg) { while (rtl && RTA_OK (rth, rtl)) { if ((rth->rta_type == IFA_LOCAL /* IPv4 */ || rth->rta_type == IFA_ADDRESS /* IPv6 */) - && ifa->ifa_scope == RT_SCOPE_UNIVERSE /* no IPv6 scope link */) + && ifa->ifa_scope == RT_SCOPE_UNIVERSE /* no IPv6 scope link */) { + inet_ntop(ifa->ifa_family, RTA_DATA (rth), buf, sizeof(buf)); + + next = &(addresses_seen[ifi->ifi_index]); + seen = 0; + + /* check if we already notified about this address */ + while (next->next != NULL) { + if (strcmp(next->address, buf) == 0 && next->prefix == ifa->ifa_prefixlen) { +#if DEBUG + printf("Already notified about address %s/%d, skipping.\n", buf, ifa->ifa_prefixlen); +#endif + seen++; + break; + } + next = next->next; + } + + if (seen) + break; + + /* add address to struct */ + next->address = strdup(buf); + next->prefix = ifa->ifa_prefixlen; + next->next = malloc(sizeof(struct addresses_seen)); + next->next->next = NULL; + + /* display notification */ notifystr = newstr_addr(TEXT_NEWADDR, name, - ifa->ifa_family, RTA_DATA (rth), ifa->ifa_prefixlen); + ifa->ifa_family, buf, ifa->ifa_prefixlen); + + /* we are done, no need to run more loops */ + break; + } rth = RTA_NEXT (rth, rtl); } if (notifystr == NULL) { @@ -206,9 +267,12 @@ static int msg_handler (struct sockaddr_nl *nl, struct nlmsghdr *msg) { return 0; case RTM_NEWLINK: notifystr = newstr_link(TEXT_NEWLINK, name, ifi->ifi_flags); + if (!(ifi->ifi_flags & CHECK_CONNECTED)) + free_chain(&(addresses_seen[ifi->ifi_index])); break; case RTM_DELLINK: notifystr = newstr_away(TEXT_DELLINK); + free_chain(&(addresses_seen[ifi->ifi_index])); break; default: /* we should not get here... */ @@ -268,7 +332,11 @@ int main (int argc, char **argv) { int nls; program = argv[0]; - printf ("%s: %s v%s (compiled: " __DATE__ ", " __TIME__ ")\n", argv[0], PROGNAME, VERSION); + printf ("%s: %s v%s (compiled: " __DATE__ ", " __TIME__ +#if DEBUG + ", with debug output" +#endif + ")\n", argv[0], PROGNAME, VERSION); nls = open_netlink (); if (nls < 0) { |