diff --git a/sys/netlink/netlink_domain.c b/sys/netlink/netlink_domain.c index 159dfd03724d..032fded987df 100644 --- a/sys/netlink/netlink_domain.c +++ b/sys/netlink/netlink_domain.c @@ -1,689 +1,690 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2021 Ng Peng Nam Sean * Copyright (c) 2022 Alexander V. Chernikov * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * This file contains socket and protocol bindings for netlink. */ #include #include #include #include #include #include #include #include #include #include #include #include #include /* priv_check */ #include #include #include #define DEBUG_MOD_NAME nl_domain #define DEBUG_MAX_LEVEL LOG_DEBUG3 #include _DECLARE_DEBUG(LOG_DEBUG); #define NLCTL_TRACKER struct rm_priotracker nl_tracker #define NLCTL_RLOCK(_ctl) rm_rlock(&((_ctl)->ctl_lock), &nl_tracker) #define NLCTL_RUNLOCK(_ctl) rm_runlock(&((_ctl)->ctl_lock), &nl_tracker) #define NLCTL_WLOCK(_ctl) rm_wlock(&((_ctl)->ctl_lock)) #define NLCTL_WUNLOCK(_ctl) rm_wunlock(&((_ctl)->ctl_lock)) static u_long nl_sendspace = NLSNDQ; SYSCTL_ULONG(_net_netlink, OID_AUTO, sendspace, CTLFLAG_RW, &nl_sendspace, 0, "Default netlink socket send space"); static u_long nl_recvspace = NLSNDQ; SYSCTL_ULONG(_net_netlink, OID_AUTO, recvspace, CTLFLAG_RW, &nl_recvspace, 0, "Default netlink socket receive space"); extern u_long sb_max_adj; static u_long nl_maxsockbuf = 512 * 1024 * 1024; /* 512M, XXX: init based on physmem */ uint32_t nlp_get_pid(const struct nlpcb *nlp) { return (nlp->nl_process_id); } /* * Looks up a nlpcb struct based on the @portid. Need to claim nlsock_mtx. * Returns nlpcb pointer if present else NULL */ static struct nlpcb * nl_port_lookup(uint32_t port_id) { struct nlpcb *nlp; CK_LIST_FOREACH(nlp, &V_nl_ctl->ctl_port_head, nl_port_next) { if (nlp->nl_port == port_id) return (nlp); } return (NULL); } static void nl_update_groups_locked(struct nlpcb *nlp, uint64_t nl_groups) { /* Update group mask */ - NL_LOG(LOG_DEBUG2, "socket %p, groups 0x%lX -> 0x%lX", - nlp->nl_socket, nlp->nl_groups, nl_groups); + NL_LOG(LOG_DEBUG2, "socket %p, groups 0x%X -> 0x%X", + nlp->nl_socket, (uint32_t)nlp->nl_groups, (uint32_t)nl_groups); nlp->nl_groups = nl_groups; } /* * Broadcasts message @m to the protocol @proto group specified by @group_id */ void nl_send_group(struct mbuf *m, int num_messages, int proto, int group_id) { struct nlpcb *nlp_last = NULL; struct nlpcb *nlp; NLCTL_TRACKER; IF_DEBUG_LEVEL(LOG_DEBUG2) { struct nlmsghdr *hdr = mtod(m, struct nlmsghdr *); NL_LOG(LOG_DEBUG2, "MCAST mbuf len %u msg type %d len %u to group %d/%d", m->m_len, hdr->nlmsg_type, hdr->nlmsg_len, proto, group_id); } struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); if (__predict_false(ctl == NULL)) { /* * Can be the case when notification is sent within VNET * which doesn't have any netlink sockets. */ m_freem(m); return; } NLCTL_RLOCK(ctl); int io_flags = NL_IOF_UNTRANSLATED; uint64_t groups_mask = 1 << ((uint64_t)group_id - 1); CK_LIST_FOREACH(nlp, &ctl->ctl_pcb_head, nl_next) { if (nlp->nl_groups & groups_mask && nlp->nl_proto == proto) { if (nlp_last != NULL) { struct mbuf *m_copy; m_copy = m_copym(m, 0, M_COPYALL, M_NOWAIT); if (m_copy != NULL) nl_send_one(m_copy, nlp_last, num_messages, io_flags); else { NLP_LOCK(nlp_last); if (nlp_last->nl_socket != NULL) sorwakeup(nlp_last->nl_socket); NLP_UNLOCK(nlp_last); } } nlp_last = nlp; } } if (nlp_last != NULL) nl_send_one(m, nlp_last, num_messages, io_flags); else m_freem(m); NLCTL_RUNLOCK(ctl); } bool nl_has_listeners(int netlink_family, uint32_t groups_mask) { return (V_nl_ctl != NULL); } bool nlp_has_priv(struct nlpcb *nlp, int priv) { return (priv_check_cred(nlp->nl_cred, priv) == 0); } static uint32_t nl_find_port() { /* * app can open multiple netlink sockets. * Start with current pid, if already taken, * try random numbers in 65k..256k+65k space, * avoiding clash with pids. */ if (nl_port_lookup(curproc->p_pid) == NULL) return (curproc->p_pid); for (int i = 0; i < 16; i++) { uint32_t nl_port = (arc4random() % 65536) + 65536 * 4; if (nl_port_lookup(nl_port) == 0) return (nl_port); NL_LOG(LOG_DEBUG3, "tried %u\n", nl_port); } return (curproc->p_pid); } static int nl_bind_locked(struct nlpcb *nlp, struct sockaddr_nl *snl) { if (nlp->nl_bound) { if (nlp->nl_port != snl->nl_pid) { NL_LOG(LOG_DEBUG, "bind() failed: program pid %d " "is different from provided pid %d", nlp->nl_port, snl->nl_pid); return (EINVAL); // XXX: better error } } else { if (snl->nl_pid == 0) snl->nl_pid = nl_find_port(); if (nl_port_lookup(snl->nl_pid) != NULL) return (EADDRINUSE); nlp->nl_port = snl->nl_pid; nlp->nl_bound = true; CK_LIST_INSERT_HEAD(&V_nl_ctl->ctl_port_head, nlp, nl_port_next); } nl_update_groups_locked(nlp, snl->nl_groups); return (0); } static int nl_pru_attach(struct socket *so, int proto, struct thread *td) { struct nlpcb *nlp; int error; if (__predict_false(netlink_unloading != 0)) return (EAFNOSUPPORT); error = nl_verify_proto(proto); if (error != 0) return (error); bool is_linux = SV_PROC_ABI(td->td_proc) == SV_ABI_LINUX; NL_LOG(LOG_DEBUG2, "socket %p, %sPID %d: attaching socket to %s", so, is_linux ? "(linux) " : "", curproc->p_pid, nl_get_proto_name(proto)); /* Create per-VNET state on first socket init */ struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); if (ctl == NULL) ctl = vnet_nl_ctl_init(); KASSERT(V_nl_ctl != NULL, ("nl_attach: vnet_sock_init() failed")); MPASS(sotonlpcb(so) == NULL); nlp = malloc(sizeof(struct nlpcb), M_PCB, M_WAITOK | M_ZERO); error = soreserve(so, nl_sendspace, nl_recvspace); if (error != 0) { free(nlp, M_PCB); return (error); } so->so_pcb = nlp; nlp->nl_socket = so; /* Copy so_cred to avoid having socket_var.h in every header */ nlp->nl_cred = so->so_cred; nlp->nl_proto = proto; nlp->nl_process_id = curproc->p_pid; nlp->nl_linux = is_linux; nlp->nl_active = true; NLP_LOCK_INIT(nlp); refcount_init(&nlp->nl_refcount, 1); nl_init_io(nlp); nlp->nl_taskqueue = taskqueue_create("netlink_socket", M_WAITOK, taskqueue_thread_enqueue, &nlp->nl_taskqueue); TASK_INIT(&nlp->nl_task, 0, nl_taskqueue_handler, nlp); taskqueue_start_threads(&nlp->nl_taskqueue, 1, PWAIT, "netlink_socket (PID %u)", nlp->nl_process_id); NLCTL_WLOCK(ctl); /* XXX: check ctl is still alive */ CK_LIST_INSERT_HEAD(&ctl->ctl_pcb_head, nlp, nl_next); NLCTL_WUNLOCK(ctl); soisconnected(so); return (0); } static void nl_pru_abort(struct socket *so) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); soisdisconnected(so); } static int nl_pru_bind(struct socket *so, struct sockaddr *sa, struct thread *td) { struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); struct nlpcb *nlp = sotonlpcb(so); struct sockaddr_nl *snl = (struct sockaddr_nl *)sa; int error; NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); if (snl->nl_len != sizeof(*snl)) { NL_LOG(LOG_DEBUG, "socket %p, wrong sizeof(), ignoring bind()", so); return (EINVAL); } NLCTL_WLOCK(ctl); NLP_LOCK(nlp); error = nl_bind_locked(nlp, snl); NLP_UNLOCK(nlp); NLCTL_WUNLOCK(ctl); NL_LOG(LOG_DEBUG2, "socket %p, bind() to %u, groups %u, error %d", so, snl->nl_pid, snl->nl_groups, error); return (error); } static int nl_assign_port(struct nlpcb *nlp, uint32_t port_id) { struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); struct sockaddr_nl snl = { .nl_pid = port_id, }; int error; NLCTL_WLOCK(ctl); NLP_LOCK(nlp); snl.nl_groups = nlp->nl_groups; error = nl_bind_locked(nlp, &snl); NLP_UNLOCK(nlp); NLCTL_WUNLOCK(ctl); NL_LOG(LOG_DEBUG3, "socket %p, port assign: %d, error: %d", nlp->nl_socket, port_id, error); return (error); } /* * nl_autobind_port binds a unused portid to @nlp * @nlp: pcb data for the netlink socket * @candidate_id: first id to consider */ static int nl_autobind_port(struct nlpcb *nlp, uint32_t candidate_id) { struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); uint32_t port_id = candidate_id; NLCTL_TRACKER; bool exist; int error; for (int i = 0; i < 10; i++) { NL_LOG(LOG_DEBUG3, "socket %p, trying to assign port %d", nlp->nl_socket, port_id); NLCTL_RLOCK(ctl); exist = nl_port_lookup(port_id) != 0; NLCTL_RUNLOCK(ctl); if (!exist) { error = nl_assign_port(nlp, port_id); if (error != EADDRINUSE) break; } port_id++; } NL_LOG(LOG_DEBUG3, "socket %p, autobind to %d, error: %d", nlp->nl_socket, port_id, error); return (error); } static int nl_pru_connect(struct socket *so, struct sockaddr *sa, struct thread *td) { struct sockaddr_nl *snl = (struct sockaddr_nl *)sa; struct nlpcb *nlp; NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); if (snl->nl_len != sizeof(*snl)) { NL_LOG(LOG_DEBUG, "socket %p, wrong sizeof(), ignoring bind()", so); return (EINVAL); } nlp = sotonlpcb(so); if (!nlp->nl_bound) { int error = nl_autobind_port(nlp, td->td_proc->p_pid); if (error != 0) { NL_LOG(LOG_DEBUG, "socket %p, nl_autobind() failed: %d", so, error); return (error); } } /* XXX: Handle socket flags & multicast */ soisconnected(so); NL_LOG(LOG_DEBUG2, "socket %p, connect to %u", so, snl->nl_pid); return (0); } static void destroy_nlpcb(struct nlpcb *nlp) { NLP_LOCK(nlp); nl_free_io(nlp); NLP_LOCK_DESTROY(nlp); free(nlp, M_PCB); } static void destroy_nlpcb_epoch(epoch_context_t ctx) { struct nlpcb *nlp; nlp = __containerof(ctx, struct nlpcb, nl_epoch_ctx); destroy_nlpcb(nlp); } static void nl_pru_detach(struct socket *so) { struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); MPASS(sotonlpcb(so) != NULL); struct nlpcb *nlp; NL_LOG(LOG_DEBUG2, "detaching socket %p, PID %d", so, curproc->p_pid); nlp = sotonlpcb(so); /* Mark as inactive so no new work can be enqueued */ NLP_LOCK(nlp); bool was_bound = nlp->nl_bound; nlp->nl_active = false; NLP_UNLOCK(nlp); /* Wait till all scheduled work has been completed */ taskqueue_drain_all(nlp->nl_taskqueue); taskqueue_free(nlp->nl_taskqueue); NLCTL_WLOCK(ctl); NLP_LOCK(nlp); if (was_bound) { CK_LIST_REMOVE(nlp, nl_port_next); NL_LOG(LOG_DEBUG3, "socket %p, unlinking bound pid %u", so, nlp->nl_port); } CK_LIST_REMOVE(nlp, nl_next); nlp->nl_socket = NULL; NLP_UNLOCK(nlp); NLCTL_WUNLOCK(ctl); so->so_pcb = NULL; NL_LOG(LOG_DEBUG3, "socket %p, detached", so); /* XXX: is delayed free needed? */ epoch_call(net_epoch_preempt, destroy_nlpcb_epoch, &nlp->nl_epoch_ctx); } static int nl_pru_disconnect(struct socket *so) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); return (ENOTCONN); } static int nl_pru_peeraddr(struct socket *so, struct sockaddr **sa) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); return (ENOTCONN); } static int nl_pru_shutdown(struct socket *so) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); socantsendmore(so); return (0); } static int nl_pru_sockaddr(struct socket *so, struct sockaddr **sa) { struct sockaddr_nl *snl; snl = malloc(sizeof(struct sockaddr_nl), M_SONAME, M_WAITOK | M_ZERO); /* TODO: set other fields */ snl->nl_len = sizeof(struct sockaddr_nl); snl->nl_family = AF_NETLINK; snl->nl_pid = sotonlpcb(so)->nl_port; *sa = (struct sockaddr *)snl; return (0); } static void nl_pru_close(struct socket *so) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); soisdisconnected(so); } static int nl_pru_output(struct mbuf *m, struct socket *so, ...) { if (__predict_false(m == NULL || ((m->m_len < sizeof(struct nlmsghdr)) && (m = m_pullup(m, sizeof(struct nlmsghdr))) == NULL))) return (ENOBUFS); MPASS((m->m_flags & M_PKTHDR) != 0); NL_LOG(LOG_DEBUG3, "sending message to kernel async processing"); nl_receive_async(m, so); return (0); } static int nl_pru_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *sa, struct mbuf *control, struct thread *td) { NL_LOG(LOG_DEBUG2, "sending message to kernel"); if (__predict_false(control != NULL)) { if (control->m_len) { m_freem(control); return (EINVAL); } m_freem(control); } return (nl_pru_output(m, so)); } static int nl_pru_rcvd(struct socket *so, int flags) { NL_LOG(LOG_DEBUG3, "socket %p, PID %d", so, curproc->p_pid); MPASS(sotonlpcb(so) != NULL); nl_on_transmit(sotonlpcb(so)); return (0); } static int nl_getoptflag(int sopt_name) { switch (sopt_name) { case NETLINK_CAP_ACK: return (NLF_CAP_ACK); case NETLINK_EXT_ACK: return (NLF_EXT_ACK); case NETLINK_GET_STRICT_CHK: return (NLF_STRICT); } return (0); } static int nl_ctloutput(struct socket *so, struct sockopt *sopt) { struct nl_control *ctl = atomic_load_ptr(&V_nl_ctl); struct nlpcb *nlp = sotonlpcb(so); uint32_t flag; uint64_t groups, group_mask; int optval, error = 0; NLCTL_TRACKER; NL_LOG(LOG_DEBUG2, "%ssockopt(%p, %d)", (sopt->sopt_dir) ? "set" : "get", so, sopt->sopt_name); switch (sopt->sopt_dir) { case SOPT_SET: switch (sopt->sopt_name) { case NETLINK_ADD_MEMBERSHIP: case NETLINK_DROP_MEMBERSHIP: sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); if (optval <= 0 || optval >= 64) { error = ERANGE; break; } group_mask = (uint64_t)1 << (optval - 1); - NL_LOG(LOG_DEBUG2, "ADD/DEL group %d mask (%lX)", optval, group_mask); + NL_LOG(LOG_DEBUG2, "ADD/DEL group %d mask (%X)", + (uint32_t)optval, (uint32_t)group_mask); NLCTL_WLOCK(ctl); if (sopt->sopt_name == NETLINK_ADD_MEMBERSHIP) groups = nlp->nl_groups | group_mask; else groups = nlp->nl_groups & ~group_mask; nl_update_groups_locked(nlp, groups); NLCTL_WUNLOCK(ctl); break; case NETLINK_CAP_ACK: case NETLINK_EXT_ACK: case NETLINK_GET_STRICT_CHK: sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); flag = nl_getoptflag(sopt->sopt_name); NLCTL_WLOCK(ctl); if (optval != 0) nlp->nl_flags |= flag; else nlp->nl_flags &= ~flag; NLCTL_WUNLOCK(ctl); break; default: error = ENOPROTOOPT; } break; case SOPT_GET: switch (sopt->sopt_name) { case NETLINK_LIST_MEMBERSHIPS: NLCTL_RLOCK(ctl); optval = nlp->nl_groups; NLCTL_RUNLOCK(ctl); error = sooptcopyout(sopt, &optval, sizeof(optval)); break; case NETLINK_CAP_ACK: case NETLINK_EXT_ACK: case NETLINK_GET_STRICT_CHK: NLCTL_RLOCK(ctl); optval = (nlp->nl_flags & nl_getoptflag(sopt->sopt_name)) != 0; NLCTL_RUNLOCK(ctl); error = sooptcopyout(sopt, &optval, sizeof(optval)); break; default: error = ENOPROTOOPT; } break; default: error = ENOPROTOOPT; } return (error); } static int nl_setsbopt(struct socket *so, struct sockopt *sopt) { int error, optval; bool result; if (sopt->sopt_name != SO_RCVBUF) return (sbsetopt(so, sopt)); /* Allow to override max buffer size in certain conditions */ error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error != 0) return (error); NL_LOG(LOG_DEBUG2, "socket %p, PID %d, SO_RCVBUF=%d", so, curproc->p_pid, optval); if (optval > sb_max_adj) { if (priv_check(curthread, PRIV_NET_ROUTE) != 0) return (EPERM); } SOCK_RECVBUF_LOCK(so); result = sbreserve_locked_limit(so, SO_RCV, optval, nl_maxsockbuf, curthread); SOCK_RECVBUF_UNLOCK(so); return (result ? 0 : ENOBUFS); } static struct protosw netlinksw = { .pr_type = SOCK_RAW, .pr_flags = PR_ATOMIC | PR_ADDR | PR_WANTRCVD, .pr_ctloutput = nl_ctloutput, .pr_setsbopt = nl_setsbopt, .pr_abort = nl_pru_abort, .pr_attach = nl_pru_attach, .pr_bind = nl_pru_bind, .pr_connect = nl_pru_connect, .pr_detach = nl_pru_detach, .pr_disconnect = nl_pru_disconnect, .pr_peeraddr = nl_pru_peeraddr, .pr_send = nl_pru_send, .pr_rcvd = nl_pru_rcvd, .pr_shutdown = nl_pru_shutdown, .pr_sockaddr = nl_pru_sockaddr, .pr_close = nl_pru_close }; static struct domain netlinkdomain = { .dom_family = PF_NETLINK, .dom_name = "netlink", .dom_flags = DOMF_UNLOADABLE, .dom_nprotosw = 1, .dom_protosw = { &netlinksw }, }; DOMAIN_SET(netlink);