Add more sanity checks and logging to DAD

[odhcp6c.git] / src / ra.c

diff --git a/src/ra.c b/src/ra.c
index 814a17decfe706dbde3da71d3749d9ff8dc7a594..7d1ded0199a512eca16828b86d32d75c75b44bab 100644 (file)
--- a/src/ra.c
+++ b/src/ra.c
@@ -18,9 +18,11 @@
 #include <string.h>
 #include <stddef.h>
 #include <stdbool.h>
+#include <syslog.h>
 #include <unistd.h>
 
 #include <net/if.h>
+#include <arpa/inet.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <netinet/icmp6.h>
@@ -165,7 +167,8 @@ bool ra_rtnl_process(void)
                        struct in6_addr *addr = NULL;
                        if (NLMSG_PAYLOAD(nh, 0) < sizeof(*ifa) || ifa->ifa_index != if_index ||
                                        (nh->nlmsg_type == RTM_NEWADDR && !(ifa->ifa_flags & IFA_F_DADFAILED)) ||
-                                       (nh->nlmsg_type == RTM_DELADDR && !(ifa->ifa_flags & IFA_F_TENTATIVE)))
+                                       (nh->nlmsg_type == RTM_DELADDR && !(ifa->ifa_flags & IFA_F_TENTATIVE)) ||
+                                       (nh->nlmsg_type != RTM_NEWADDR && nh->nlmsg_type != RTM_DELADDR))
                                continue;
 
                        ssize_t alen = NLMSG_PAYLOAD(nh, sizeof(*ifa));
@@ -174,8 +177,13 @@ bool ra_rtnl_process(void)
                                if (rta->rta_type == IFA_ADDRESS && RTA_PAYLOAD(rta) >= sizeof(*addr))
                                        addr = RTA_DATA(rta);
 
-                       if (addr)
+                       if (addr) {
+                               char ipbuf[INET6_ADDRSTRLEN];
+                               inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf));
+                               syslog(LOG_WARNING, "duplicate address detected: %s (code: %u:%x)",
+                                               ipbuf, (unsigned)nh->nlmsg_type, (unsigned)ifa->ifa_flags);
                                found |= ra_deduplicate(addr, ifa->ifa_prefixlen);
+                       }
                }
        }
        return found;
@@ -230,13 +238,15 @@ bool ra_process(void)
                struct icmpv6_opt *opt;
                icmpv6_for_each_option(opt, &adv[1], &buf[len]) {
                        if (opt->type == ND_OPT_MTU) {
-                               update_proc("conf", "mtu", ntohl(*((uint32_t*)&opt->data[2])));
+                               uint32_t *mtu = (uint32_t*)&opt->data[2];
+                               update_proc("conf", "mtu", ntohl(*mtu));
                        } else if (opt->type == ND_OPT_ROUTE_INFORMATION && opt->len <= 3) {
                                entry.router = from.sin6_addr;
                                entry.target = any;
                                entry.priority = pref_to_priority(opt->data[1]);
                                entry.length = opt->data[0];
-                               entry.valid = ntohl(*((uint32_t*)&opt->data[2]));
+                               uint32_t *valid = (uint32_t*)&opt->data[2];
+                               entry.valid = ntohl(*valid);
                                memcpy(&entry.target, &opt->data[6], (opt->len - 1) * 8);
 
                                if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target)
@@ -276,7 +286,8 @@ bool ra_process(void)
                                entry.router = from.sin6_addr;
                                entry.priority = 0;
                                entry.length = 128;
-                               entry.valid = ntohl(*((uint32_t*)&opt->data[2]));
+                               uint32_t *valid = (uint32_t*)&opt->data[2];
+                               entry.valid = ntohl(*valid);
                                entry.preferred = 0;
 
                                for (ssize_t i = 0; i < (opt->len - 1) / 2; ++i) {