Don't fork on IPv6 RA unless we have an RDNSS option.

diff --git a/ipv6rs.c b/ipv6rs.c
index d37ff8976fe73eae821e451b8a383ad6786a39ca..4c5f67a88b45dfe9e792b494e7e63f8d4696daab 100644 (file)
--- a/ipv6rs.c
+++ b/ipv6rs.c
@@ -274,6 +274,7 @@ ipv6rs_handledata(_unused void *arg)
        struct ra_opt *rao, *raol;
        char *opt;
        struct timeval expire;
+       int has_dns;
 
        len = recvmsg(sock, &rcvhdr, 0);
        if (len == -1) {
@@ -381,6 +382,7 @@ ipv6rs_handledata(_unused void *arg)
        p = ((uint8_t *)icp) + sizeof(struct nd_router_advert);
        olen = 0;
        lifetime = ~0U;
+       has_dns = 0;
        for (olen = 0; len > 0; p += olen, len -= olen) {
                if ((size_t)len < sizeof(struct nd_opt_hdr)) {
                        syslog(LOG_ERR, "%s: Short option", ifp->name);
@@ -466,6 +468,7 @@ ipv6rs_handledata(_unused void *arg)
                                                    '\0';
                                        } else
                                                opt = xstrdup(cbp);
+                                       has_dns = 1;
                                }
                                op += sizeof(addr.s6_addr);
                        }
@@ -532,10 +535,16 @@ ipv6rs_handledata(_unused void *arg)
        if (options & DHCPCD_TEST)
                exit(EXIT_SUCCESS);
 
-       delete_q_timeout(0, handle_exit_timeout, NULL);
+       if (has_dns)
+               delete_q_timeout(0, handle_exit_timeout, NULL);
        delete_timeouts(ifp, NULL);
        ipv6rs_expire(ifp);
-       daemonise();
+       if (has_dns)
+               daemonise();
+       else if (options & DHCPCD_DAEMONISE && !(options & DHCPCD_DAEMONISED))
+               syslog(LOG_WARNING,
+                   "%s: did not fork due to an absent RDNSS option in the RA",
+                   ifp->name);
 }
 
 ssize_t