Author: melifaro Date: Fri Dec 18 22:00:57 2020 New Revision: 368769 URL: https://svnweb.freebsd.org/changeset/base/368769
Log: Switch direct rt fields access in rtsock.c to newly-create field acessors. rtsock code was build around the assumption that each rtentry record in the system radix tree is a ready-to-use sockaddr. This assumptions turned out to be not quite true: * masks have their length tweaked, so we have rtsock_fix_netmask() hack * IPv6 addresses have their scope embedded, so we have another explicit deembedding hack. Change the code to decouple rtentry internals from rtsock code using newly-created rtentry accessors. This will allow to eventually eliminate both of the hacks and change rtentry dst/mask format. Differential Revision: https://reviews.freebsd.org/D27451 Modified: head/sys/net/rtsock.c Modified: head/sys/net/rtsock.c ============================================================================== --- head/sys/net/rtsock.c Fri Dec 18 20:41:23 2020 (r368768) +++ head/sys/net/rtsock.c Fri Dec 18 22:00:57 2020 (r368769) @@ -158,10 +158,13 @@ MTX_SYSINIT(rtsock, &rtsock_mtx, "rtsock route_cb lock SYSCTL_NODE(_net, OID_AUTO, route, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, ""); struct walkarg { + int family; int w_tmemsize; int w_op, w_arg; caddr_t w_tmem; struct sysctl_req *w_req; + struct sockaddr *dst; + struct sockaddr *mask; }; static void rts_input(struct mbuf *m); @@ -170,7 +173,7 @@ static int rtsock_msg_buffer(int type, struct rt_addri struct walkarg *w, int *plen); static int rt_xaddrs(caddr_t cp, caddr_t cplim, struct rt_addrinfo *rtinfo); -static int sysctl_dumpentry(struct radix_node *rn, void *vw); +static int sysctl_dumpentry(struct rtentry *rt, void *vw); static int sysctl_dumpnhop(struct rtentry *rt, struct nhop_object *nh, uint32_t weight, struct walkarg *w); static int sysctl_iflist(int af, struct walkarg *w); @@ -187,7 +190,8 @@ static int update_rtm_from_rc(struct rt_addrinfo *info static void send_rtm_reply(struct socket *so, struct rt_msghdr *rtm, struct mbuf *m, sa_family_t saf, u_int fibnum, int rtm_errno); -static int can_export_rte(struct ucred *td_ucred, const struct rtentry *rt); +static bool can_export_rte(struct ucred *td_ucred, bool rt_is_host, + const struct sockaddr *rt_dst); static struct netisr_handler rtsock_nh = { .nh_name = "rtsock", @@ -707,7 +711,7 @@ handle_rtm_get(struct rt_addrinfo *info, u_int fibnum, return (ESRCH); } - nh = select_nhop(rc->rc_rt->rt_nhop, info->rti_info[RTAX_GATEWAY]); + nh = select_nhop(rt_get_raw_nhop(rc->rc_rt), info->rti_info[RTAX_GATEWAY]); if (nh == NULL) { RIB_RUNLOCK(rnh); return (ESRCH); @@ -721,9 +725,7 @@ handle_rtm_get(struct rt_addrinfo *info, u_int fibnum, */ if (rtm->rtm_flags & RTF_ANNOUNCE) { struct sockaddr laddr; - struct nhop_object *nh; - nh = rc->rc_rt->rt_nhop; if (nh->nh_ifp != NULL && nh->nh_ifp->if_type == IFT_PROPVIRTUAL) { struct ifaddr *ifa; @@ -747,7 +749,7 @@ handle_rtm_get(struct rt_addrinfo *info, u_int fibnum, RIB_RUNLOCK(rnh); return (ESRCH); } - nh = select_nhop(rc->rc_rt->rt_nhop, info->rti_info[RTAX_GATEWAY]); + nh = select_nhop(rt_get_raw_nhop(rc->rc_rt), info->rti_info[RTAX_GATEWAY]); if (nh == NULL) { RIB_RUNLOCK(rnh); return (ESRCH); @@ -760,6 +762,66 @@ handle_rtm_get(struct rt_addrinfo *info, u_int fibnum, return (0); } +static void +init_sockaddrs_family(int family, struct sockaddr *dst, struct sockaddr *mask) +{ +#ifdef INET + if (family == AF_INET) { + struct sockaddr_in *dst4 = (struct sockaddr_in *)dst; + struct sockaddr_in *mask4 = (struct sockaddr_in *)mask; + + bzero(dst4, sizeof(struct sockaddr_in)); + bzero(mask4, sizeof(struct sockaddr_in)); + + dst4->sin_family = AF_INET; + dst4->sin_len = sizeof(struct sockaddr_in); + mask4->sin_family = AF_INET; + mask4->sin_len = sizeof(struct sockaddr_in); + } +#endif +#ifdef INET6 + if (family == AF_INET6) { + struct sockaddr_in6 *dst6 = (struct sockaddr_in6 *)dst; + struct sockaddr_in6 *mask6 = (struct sockaddr_in6 *)mask; + + bzero(dst6, sizeof(struct sockaddr_in6)); + bzero(mask6, sizeof(struct sockaddr_in6)); + + dst6->sin6_family = AF_INET6; + dst6->sin6_len = sizeof(struct sockaddr_in6); + mask6->sin6_family = AF_INET6; + mask6->sin6_len = sizeof(struct sockaddr_in6); + } +#endif +} + +static void +export_rtaddrs(const struct rtentry *rt, struct sockaddr *dst, + struct sockaddr *mask) +{ + uint32_t scopeid = 0; +#ifdef INET + if (dst->sa_family == AF_INET) { + struct sockaddr_in *dst4 = (struct sockaddr_in *)dst; + struct sockaddr_in *mask4 = (struct sockaddr_in *)mask; + rt_get_inet_prefix_pmask(rt, &dst4->sin_addr, &mask4->sin_addr, + &scopeid); + return; + } +#endif +#ifdef INET6 + if (dst->sa_family == AF_INET6) { + struct sockaddr_in6 *dst6 = (struct sockaddr_in6 *)dst; + struct sockaddr_in6 *mask6 = (struct sockaddr_in6 *)mask; + rt_get_inet6_prefix_pmask(rt, &dst6->sin6_addr, &mask6->sin6_addr, + &scopeid); + dst6->sin6_scope_id = scopeid; + return; + } +#endif +} + + /* * Update sockaddrs, flags, etc in @prtm based on @rc data. * rtm can be reallocated. @@ -772,7 +834,6 @@ 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) { - struct sockaddr_storage netmask_ss; struct walkarg w; union sockaddr_union saun; struct rt_msghdr *rtm, *orig_rtm = NULL; @@ -780,11 +841,14 @@ update_rtm_from_rc(struct rt_addrinfo *info, struct rt 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, &sa_mask.sa); + export_rtaddrs(rc->rc_rt, &sa_dst.sa, &sa_mask.sa); - info->rti_info[RTAX_DST] = rt_key(rc->rc_rt); + 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_NETMASK] = rtsock_fix_netmask(rt_key(rc->rc_rt), - rt_mask(rc->rc_rt), &netmask_ss); info->rti_info[RTAX_GENMASK] = 0; ifp = nh->nh_ifp; if (rtm->rtm_addrs & (RTA_IFP | RTA_IFA)) { @@ -994,7 +1058,9 @@ route_output(struct mbuf *m, struct socket *so, ...) nh = rc.rc_nh_new; report: - if (!can_export_rte(curthread->td_ucred, rc.rc_rt)) { + if (!can_export_rte(curthread->td_ucred, + info.rti_info[RTAX_NETMASK] == NULL, + info.rti_info[RTAX_DST])) { senderr(ESRCH); } @@ -1730,35 +1796,34 @@ rt_dispatch(struct mbuf *m, sa_family_t saf) * * Returns 1 if it can, 0 otherwise. */ -static int -can_export_rte(struct ucred *td_ucred, const struct rtentry *rt) +static bool +can_export_rte(struct ucred *td_ucred, bool rt_is_host, + const struct sockaddr *rt_dst) { - if ((rt->rte_flags & RTF_HOST) == 0 - ? jailed_without_vnet(td_ucred) - : prison_if(td_ucred, rt_key_const(rt)) != 0) - return (0); - return (1); + if ((!rt_is_host) ? jailed_without_vnet(td_ucred) + : prison_if(td_ucred, rt_dst) != 0) + return (false); + return (true); } + /* * This is used in dumping the kernel table via sysctl(). */ static int -sysctl_dumpentry(struct radix_node *rn, void *vw) +sysctl_dumpentry(struct rtentry *rt, void *vw) { struct walkarg *w = vw; - struct rtentry *rt = (struct rtentry *)rn; struct nhop_object *nh; int error = 0; NET_EPOCH_ASSERT(); - if (w->w_op == NET_RT_FLAGS && !(rt->rte_flags & w->w_arg)) - return 0; - if (!can_export_rte(w->w_req->td->td_ucred, rt)) + export_rtaddrs(rt, w->dst, w->mask); + if (!can_export_rte(w->w_req->td->td_ucred, rt_is_host(rt), w->dst)) return (0); - nh = rt->rt_nhop; + nh = rt_get_raw_nhop(rt); #ifdef ROUTE_MPATH if (NH_IS_NHGRP(nh)) { struct weightened_nhop *wn; @@ -1783,13 +1848,17 @@ sysctl_dumpnhop(struct rtentry *rt, struct nhop_object { struct rt_addrinfo info; int error = 0, size; - struct sockaddr_storage ss; + uint32_t rtflags; + rtflags = nhop_get_rtflags(nh); + + if (w->w_op == NET_RT_FLAGS && !(rtflags & w->w_arg)) + return (0); + bzero((caddr_t)&info, sizeof(info)); - info.rti_info[RTAX_DST] = rt_key(rt); + info.rti_info[RTAX_DST] = w->dst; info.rti_info[RTAX_GATEWAY] = &nh->gw_sa; - info.rti_info[RTAX_NETMASK] = rtsock_fix_netmask(rt_key(rt), - rt_mask(rt), &ss); + info.rti_info[RTAX_NETMASK] = (rtflags & RTF_HOST) ? NULL : w->mask; info.rti_info[RTAX_GENMASK] = 0; if (nh->nh_ifp && !(nh->nh_ifp->if_flags & IFF_DYING)) { info.rti_info[RTAX_IFP] = nh->nh_ifp->if_addr->ifa_addr; @@ -1804,12 +1873,16 @@ sysctl_dumpnhop(struct rtentry *rt, struct nhop_object bzero(&rtm->rtm_index, sizeof(*rtm) - offsetof(struct rt_msghdr, rtm_index)); - if (rt->rte_flags & RTF_GWFLAG_COMPAT) + + /* + * rte flags may consist of RTF_HOST (duplicated in nhop rtflags) + * and RTF_UP (if entry is linked, which is always true here). + * Given that, use nhop rtflags & add RTF_UP. + */ + rtm->rtm_flags = rtflags | RTF_UP; + if (rtm->rtm_flags & RTF_GWFLAG_COMPAT) rtm->rtm_flags = RTF_GATEWAY | - (rt->rte_flags & ~RTF_GWFLAG_COMPAT); - else - rtm->rtm_flags = rt->rte_flags; - rtm->rtm_flags |= nhop_get_rtflags(nh); + (rtm->rtm_flags & ~RTF_GWFLAG_COMPAT); rt_getmetrics(rt, nh, &rtm->rtm_rmx); rtm->rtm_rmx.rmx_weight = weight; rtm->rtm_index = nh->nh_ifp->if_index; @@ -2075,10 +2148,23 @@ sysctl_ifmalist(int af, struct walkarg *w) return (error); } +static void +rtable_sysctl_dump(uint32_t fibnum, int family, struct walkarg *w) +{ + union sockaddr_union sa_dst, sa_mask; + + w->family = family; + w->dst = (struct sockaddr *)&sa_dst; + w->mask = (struct sockaddr *)&sa_mask; + + init_sockaddrs_family(family, w->dst, w->mask); + + rib_walk(fibnum, family, false, sysctl_dumpentry, w); +} + static int sysctl_rtsock(SYSCTL_HANDLER_ARGS) { - RIB_RLOCK_TRACKER; struct epoch_tracker et; int *name = (int *)arg1; u_int namelen = arg2; @@ -2151,10 +2237,7 @@ sysctl_rtsock(SYSCTL_HANDLER_ARGS) for (error = 0; error == 0 && i <= lim; i++) { rnh = rt_tables_get_rnh(fib, i); if (rnh != NULL) { - RIB_RLOCK(rnh); - error = rnh->rnh_walktree(&rnh->head, - sysctl_dumpentry, &w); - RIB_RUNLOCK(rnh); + rtable_sysctl_dump(fib, i, &w); } else if (af != 0) error = EAFNOSUPPORT; } _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
