Function update_rtm_from_rc

lib/ff_route.c:934–1014

}

static int
update_rtm_from_rc(struct rt_addrinfo *info, struct rt_msghdr **prtm,
    int alloc_len, struct rib_cmd_info *rc, struct nhop_object *nh, unsigned maxlen)
{
    struct walkarg w;
    union sockaddr_union saun;
    struct rt_msghdr *rtm, *orig_rtm = NULL;
    struct ifnet *ifp;
    int error, len;

    rtm = *prtm;
    union sockaddr_union sa_dst, sa_mask;
    int family = info->rti_info[RTAX_DST]->sa_family;
    init_sockaddrs_family(family, &sa_dst, &sa_mask);
    export_rtaddrs(rc->rc_rt, &sa_dst.sa, &sa_mask.sa);

    info->rti_info[RTAX_DST] = &sa_dst.sa;
    info->rti_info[RTAX_NETMASK] = rt_is_host(rc->rc_rt) ? NULL : &sa_mask.sa;
    info->rti_info[RTAX_GATEWAY] = &nh->gw_sa;
    info->rti_info[RTAX_GENMASK] = 0;
    ifp = nh->nh_ifp;
    if (rtm->rtm_addrs & (RTA_IFP | RTA_IFA)) {
        if (ifp) {
            info->rti_info[RTAX_IFP] =
                ifp->if_addr->ifa_addr;
            error = rtm_get_jailed(info, ifp, nh,
                &saun, curthread->td_ucred);
            if (error != 0)
                return (error);
            if (ifp->if_flags & IFF_POINTOPOINT)
                info->rti_info[RTAX_BRD] =
                    nh->nh_ifa->ifa_dstaddr;
            rtm->rtm_index = ifp->if_index;
        } else {
            info->rti_info[RTAX_IFP] = NULL;
            info->rti_info[RTAX_IFA] = NULL;
        }
    } else if (ifp != NULL)
        rtm->rtm_index = ifp->if_index;

    /* Check if we need to realloc storage */
    rtsock_msg_buffer(rtm->rtm_type, info, NULL, &len);
    if (len > maxlen) {
        return (ENOBUFS);
    }

    if (len > alloc_len) {
        struct rt_msghdr *tmp_rtm;

        tmp_rtm = malloc(len, M_TEMP, M_NOWAIT);
        if (tmp_rtm == NULL)
            return (ENOBUFS);
        bcopy(rtm, tmp_rtm, rtm->rtm_msglen);
        orig_rtm = rtm;
        rtm = tmp_rtm;
        alloc_len = len;

        /*