/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993 * The Regents of the University of California. * Copyright (c) 2004 The FreeBSD Foundation * Copyright (c) 2004-2008 Robert N. M. Watson * All rights reserved. * * 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. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. */ /* * Comments on the socket life cycle: * * soalloc() sets of socket layer state for a socket, called only by * socreate() and sonewconn(). Socket layer private. * * sodealloc() tears down socket layer state for a socket, called only by * sofree() and sonewconn(). Socket layer private. * * pru_attach() associates protocol layer state with an allocated socket; * called only once, may fail, aborting socket allocation. This is called * from socreate() and sonewconn(). Socket layer private. * * pru_detach() disassociates protocol layer state from an attached socket, * and will be called exactly once for sockets in which pru_attach() has * been successfully called. If pru_attach() returned an error, * pru_detach() will not be called. Socket layer private. * * pru_abort() and pru_close() notify the protocol layer that the last * consumer of a socket is starting to tear down the socket, and that the * protocol should terminate the connection. Historically, pru_abort() also * detached protocol state from the socket state, but this is no longer the * case. * * socreate() creates a socket and attaches protocol state. This is a public * interface that may be used by socket layer consumers to create new * sockets. * * sonewconn() creates a socket and attaches protocol state. This is a * public interface that may be used by protocols to create new sockets when * a new connection is received and will be available for accept() on a * listen socket. * * soclose() destroys a socket after possibly waiting for it to disconnect. * This is a public interface that socket consumers should use to close and * release a socket when done with it. * * soabort() destroys a socket without waiting for it to disconnect (used * only for incoming connections that are already partially or fully * connected). This is used internally by the socket layer when clearing * listen socket queues (due to overflow or close on the listen socket), but * is also a public interface protocols may use to abort connections in * their incomplete listen queues should they no longer be required. Sockets * placed in completed connection listen queues should not be aborted for * reasons described in the comment above the soclose() implementation. This * is not a general purpose close routine, and except in the specific * circumstances described here, should not be used. * * sofree() will free a socket and its protocol state if all references on * the socket have been released, and is the public interface to attempt to * free a socket when a reference is removed. This is a socket layer private * interface. * * NOTE: In addition to socreate() and soclose(), which provide a single * socket reference to the consumer to be managed as required, there are two * calls to explicitly manage socket references, soref(), and sorele(). * Currently, these are generally required only when transitioning a socket * from a listen queue to a file descriptor, in order to prevent garbage * collection of the socket at an untimely moment. For a number of reasons, * these interfaces are not preferred, and should be avoided. * * NOTE: With regard to VNETs the general rule is that callers do not set * curvnet. Exceptions to this rule include soabort(), sodisconnect(), * sofree(), sorele(), sonewconn() and sorflush(), which are usually called * from a pre-set VNET context. sopoll() currently does not need a VNET * context to be set. */ #include #include "opt_inet.h" #include "opt_inet6.h" #include "opt_kern_tls.h" #include "opt_ktrace.h" #include "opt_sctp.h" #include #include #include #include #include #include #include #include #include #include #include #include /* for struct knote */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef COMPAT_FREEBSD32 #include #include #include #endif static int soreceive_generic_locked(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp, struct mbuf **controlp, int *flagsp); static int soreceive_rcvoob(struct socket *so, struct uio *uio, int flags); static int soreceive_stream_locked(struct socket *so, struct sockbuf *sb, struct sockaddr **psa, struct uio *uio, struct mbuf **mp, struct mbuf **controlp, int flags); static int sosend_generic_locked(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td); static void so_rdknl_lock(void *); static void so_rdknl_unlock(void *); static void so_rdknl_assert_lock(void *, int); static void so_wrknl_lock(void *); static void so_wrknl_unlock(void *); static void so_wrknl_assert_lock(void *, int); static void filt_sordetach(struct knote *kn); static int filt_soread(struct knote *kn, long hint); static void filt_sowdetach(struct knote *kn); static int filt_sowrite(struct knote *kn, long hint); static int filt_soempty(struct knote *kn, long hint); fo_kqfilter_t soo_kqfilter; static struct filterops soread_filtops = { .f_isfd = 1, .f_detach = filt_sordetach, .f_event = filt_soread, }; static struct filterops sowrite_filtops = { .f_isfd = 1, .f_detach = filt_sowdetach, .f_event = filt_sowrite, }; static struct filterops soempty_filtops = { .f_isfd = 1, .f_detach = filt_sowdetach, .f_event = filt_soempty, }; so_gen_t so_gencnt; /* generation count for sockets */ MALLOC_DEFINE(M_SONAME, "soname", "socket name"); MALLOC_DEFINE(M_PCB, "pcb", "protocol control block"); #define VNET_SO_ASSERT(so) \ VNET_ASSERT(curvnet != NULL, \ ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so))); #ifdef SOCKET_HHOOK VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]); #define V_socket_hhh VNET(socket_hhh) static inline int hhook_run_socket(struct socket *, void *, int32_t); #endif #ifdef COMPAT_FREEBSD32 #ifdef __amd64__ /* off_t has 4-byte alignment on i386 but not on other 32-bit platforms. */ #define __splice32_packed __packed #else #define __splice32_packed #endif struct splice32 { int32_t sp_fd; int64_t sp_max; struct timeval32 sp_idle; } __splice32_packed; #undef __splice32_packed #endif /* * Limit on the number of connections in the listen queue waiting * for accept(2). * NB: The original sysctl somaxconn is still available but hidden * to prevent confusion about the actual purpose of this number. */ static u_int somaxconn = SOMAXCONN; static int sysctl_somaxconn(SYSCTL_HANDLER_ARGS) { int error; int val; val = somaxconn; error = sysctl_handle_int(oidp, &val, 0, req); if (error || !req->newptr ) return (error); /* * The purpose of the UINT_MAX / 3 limit, is so that the formula * 3 * so_qlimit / 2 * below, will not overflow. */ if (val < 1 || val > UINT_MAX / 3) return (EINVAL); somaxconn = val; return (0); } SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue, CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int), sysctl_somaxconn, "I", "Maximum listen socket pending connection accept queue size"); SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_MPSAFE, 0, sizeof(int), sysctl_somaxconn, "I", "Maximum listen socket pending connection accept queue size (compat)"); static int numopensockets; SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD, &numopensockets, 0, "Number of open sockets"); /* * so_global_mtx protects so_gencnt, numopensockets, and the per-socket * so_gencnt field. */ static struct mtx so_global_mtx; MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF); /* * General IPC sysctl name space, used by sockets and a variety of other IPC * types. */ SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "IPC"); /* * Initialize the socket subsystem and set up the socket * memory allocator. */ static uma_zone_t socket_zone; int maxsockets; static void socket_zone_change(void *tag) { maxsockets = uma_zone_set_max(socket_zone, maxsockets); } static int splice_init_state; static struct sx splice_init_lock; SX_SYSINIT(splice_init_lock, &splice_init_lock, "splice_init"); static SYSCTL_NODE(_kern_ipc, OID_AUTO, splice, CTLFLAG_RW, 0, "Settings relating to the SO_SPLICE socket option"); static bool splice_receive_stream = true; SYSCTL_BOOL(_kern_ipc_splice, OID_AUTO, receive_stream, CTLFLAG_RWTUN, &splice_receive_stream, 0, "Use soreceive_stream() for stream splices"); static uma_zone_t splice_zone; static struct proc *splice_proc; struct splice_wq { struct mtx mtx; STAILQ_HEAD(, so_splice) head; bool running; } __aligned(CACHE_LINE_SIZE); static struct splice_wq *splice_wq; static uint32_t splice_index = 0; static void so_splice_timeout(void *arg, int pending); static void so_splice_xfer(struct so_splice *s); static int so_unsplice(struct socket *so, bool timeout); static void splice_work_thread(void *ctx) { struct splice_wq *wq = ctx; struct so_splice *s, *s_temp; STAILQ_HEAD(, so_splice) local_head; int cpu; cpu = wq - splice_wq; if (bootverbose) printf("starting so_splice worker thread for CPU %d\n", cpu); for (;;) { mtx_lock(&wq->mtx); while (STAILQ_EMPTY(&wq->head)) { wq->running = false; mtx_sleep(wq, &wq->mtx, 0, "-", 0); wq->running = true; } STAILQ_INIT(&local_head); STAILQ_CONCAT(&local_head, &wq->head); STAILQ_INIT(&wq->head); mtx_unlock(&wq->mtx); STAILQ_FOREACH_SAFE(s, &local_head, next, s_temp) { mtx_lock(&s->mtx); CURVNET_SET(s->src->so_vnet); so_splice_xfer(s); CURVNET_RESTORE(); } } } static void so_splice_dispatch_async(struct so_splice *sp) { struct splice_wq *wq; bool running; wq = &splice_wq[sp->wq_index]; mtx_lock(&wq->mtx); STAILQ_INSERT_TAIL(&wq->head, sp, next); running = wq->running; mtx_unlock(&wq->mtx); if (!running) wakeup(wq); } void so_splice_dispatch(struct so_splice *sp) { mtx_assert(&sp->mtx, MA_OWNED); if (sp->state != SPLICE_IDLE) { mtx_unlock(&sp->mtx); } else { sp->state = SPLICE_QUEUED; mtx_unlock(&sp->mtx); so_splice_dispatch_async(sp); } } static int splice_zinit(void *mem, int size __unused, int flags __unused) { struct so_splice *s; s = (struct so_splice *)mem; mtx_init(&s->mtx, "so_splice", NULL, MTX_DEF); return (0); } static void splice_zfini(void *mem, int size) { struct so_splice *s; s = (struct so_splice *)mem; mtx_destroy(&s->mtx); } static int splice_init(void) { struct thread *td; int error, i, state; state = atomic_load_acq_int(&splice_init_state); if (__predict_true(state > 0)) return (0); if (state < 0) return (ENXIO); sx_xlock(&splice_init_lock); if (splice_init_state != 0) { sx_xunlock(&splice_init_lock); return (0); } splice_zone = uma_zcreate("splice", sizeof(struct so_splice), NULL, NULL, splice_zinit, splice_zfini, UMA_ALIGN_CACHE, 0); splice_wq = mallocarray(mp_maxid + 1, sizeof(*splice_wq), M_TEMP, M_WAITOK | M_ZERO); /* * Initialize the workqueues to run the splice work. We create a * work queue for each CPU. */ CPU_FOREACH(i) { STAILQ_INIT(&splice_wq[i].head); mtx_init(&splice_wq[i].mtx, "splice work queue", NULL, MTX_DEF); } /* Start kthreads for each workqueue. */ error = 0; CPU_FOREACH(i) { error = kproc_kthread_add(splice_work_thread, &splice_wq[i], &splice_proc, &td, 0, 0, "so_splice", "thr_%d", i); if (error) { printf("Can't add so_splice thread %d error %d\n", i, error); break; } /* * It's possible to create loops with SO_SPLICE; ensure that * worker threads aren't able to starve the system too easily. */ thread_lock(td); sched_prio(td, PUSER); thread_unlock(td); } splice_init_state = error != 0 ? -1 : 1; sx_xunlock(&splice_init_lock); return (error); } /* * Lock a pair of socket's I/O locks for splicing. Avoid blocking while holding * one lock in order to avoid potential deadlocks in case there is some other * code path which acquires more than one I/O lock at a time. */ static void splice_lock_pair(struct socket *so_src, struct socket *so_dst) { int error; for (;;) { error = SOCK_IO_SEND_LOCK(so_dst, SBL_WAIT | SBL_NOINTR); KASSERT(error == 0, ("%s: failed to lock send I/O lock: %d", __func__, error)); error = SOCK_IO_RECV_LOCK(so_src, 0); KASSERT(error == 0 || error == EWOULDBLOCK, ("%s: failed to lock recv I/O lock: %d", __func__, error)); if (error == 0) break; SOCK_IO_SEND_UNLOCK(so_dst); error = SOCK_IO_RECV_LOCK(so_src, SBL_WAIT | SBL_NOINTR); KASSERT(error == 0, ("%s: failed to lock recv I/O lock: %d", __func__, error)); error = SOCK_IO_SEND_LOCK(so_dst, 0); KASSERT(error == 0 || error == EWOULDBLOCK, ("%s: failed to lock send I/O lock: %d", __func__, error)); if (error == 0) break; SOCK_IO_RECV_UNLOCK(so_src); } } static void splice_unlock_pair(struct socket *so_src, struct socket *so_dst) { SOCK_IO_RECV_UNLOCK(so_src); SOCK_IO_SEND_UNLOCK(so_dst); } /* * Move data from the source to the sink. Assumes that both of the relevant * socket I/O locks are held. */ static int so_splice_xfer_data(struct socket *so_src, struct socket *so_dst, off_t max, ssize_t *lenp) { struct uio uio; struct mbuf *m; struct sockbuf *sb_src, *sb_dst; ssize_t len; long space; int error, flags; SOCK_IO_RECV_ASSERT_LOCKED(so_src); SOCK_IO_SEND_ASSERT_LOCKED(so_dst); error = 0; m = NULL; memset(&uio, 0, sizeof(uio)); sb_src = &so_src->so_rcv; sb_dst = &so_dst->so_snd; space = sbspace(sb_dst); if (space < 0) space = 0; len = MIN(max, MIN(space, sbavail(sb_src))); if (len == 0) { SOCK_RECVBUF_LOCK(so_src); if ((sb_src->sb_state & SBS_CANTRCVMORE) != 0) error = EPIPE; SOCK_RECVBUF_UNLOCK(so_src); } else { flags = MSG_DONTWAIT; uio.uio_resid = len; if (splice_receive_stream && sb_src->sb_tls_info == NULL) { error = soreceive_stream_locked(so_src, sb_src, NULL, &uio, &m, NULL, flags); } else { error = soreceive_generic_locked(so_src, NULL, &uio, &m, NULL, &flags); } if (error != 0 && m != NULL) { m_freem(m); m = NULL; } } if (m != NULL) { len -= uio.uio_resid; error = sosend_generic_locked(so_dst, NULL, NULL, m, NULL, MSG_DONTWAIT, curthread); } else if (error == 0) { len = 0; SOCK_SENDBUF_LOCK(so_dst); if ((sb_dst->sb_state & SBS_CANTSENDMORE) != 0) error = EPIPE; SOCK_SENDBUF_UNLOCK(so_dst); } if (error == 0) *lenp = len; return (error); } /* * Transfer data from the source to the sink. * * If "direct" is true, the transfer is done in the context of whichever thread * is operating on one of the socket buffers. We do not know which locks are * held, so we can only trylock the socket buffers; if this fails, we fall back * to the worker thread, which invokes this routine with "direct" set to false. */ static void so_splice_xfer(struct so_splice *sp) { struct socket *so_src, *so_dst; off_t max; ssize_t len; int error; mtx_assert(&sp->mtx, MA_OWNED); KASSERT(sp->state == SPLICE_QUEUED || sp->state == SPLICE_CLOSING, ("so_splice_xfer: invalid state %d", sp->state)); KASSERT(sp->max != 0, ("so_splice_xfer: max == 0")); if (sp->state == SPLICE_CLOSING) { /* Userspace asked us to close the splice. */ goto closing; } sp->state = SPLICE_RUNNING; so_src = sp->src; so_dst = sp->dst; max = sp->max > 0 ? sp->max - so_src->so_splice_sent : OFF_MAX; if (max < 0) max = 0; /* * Lock the sockets in order to block userspace from doing anything * sneaky. If an error occurs or one of the sockets can no longer * transfer data, we will automatically unsplice. */ mtx_unlock(&sp->mtx); splice_lock_pair(so_src, so_dst); error = so_splice_xfer_data(so_src, so_dst, max, &len); mtx_lock(&sp->mtx); /* * Update our stats while still holding the socket locks. This * synchronizes with getsockopt(SO_SPLICE), see the comment there. */ if (error == 0) { KASSERT(len >= 0, ("%s: len %zd < 0", __func__, len)); so_src->so_splice_sent += len; } splice_unlock_pair(so_src, so_dst); switch (sp->state) { case SPLICE_CLOSING: closing: sp->state = SPLICE_CLOSED; wakeup(sp); mtx_unlock(&sp->mtx); break; case SPLICE_RUNNING: if (error != 0 || (sp->max > 0 && so_src->so_splice_sent >= sp->max)) { sp->state = SPLICE_EXCEPTION; soref(so_src); mtx_unlock(&sp->mtx); (void)so_unsplice(so_src, false); sorele(so_src); } else { /* * Locklessly check for additional bytes in the source's * receive buffer and queue more work if possible. We * may end up queuing needless work, but that's ok, and * if we race with a thread inserting more data into the * buffer and observe sbavail() == 0, the splice mutex * ensures that splice_push() will queue more work for * us. */ if (sbavail(&so_src->so_rcv) > 0 && sbspace(&so_dst->so_snd) > 0) { sp->state = SPLICE_QUEUED; mtx_unlock(&sp->mtx); so_splice_dispatch_async(sp); } else { sp->state = SPLICE_IDLE; mtx_unlock(&sp->mtx); } } break; default: __assert_unreachable(); } } static void socket_init(void *tag) { socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); maxsockets = uma_zone_set_max(socket_zone, maxsockets); uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached"); EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL, EVENTHANDLER_PRI_FIRST); } SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL); #ifdef SOCKET_HHOOK static void socket_hhook_register(int subtype) { if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype, &V_socket_hhh[subtype], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) printf("%s: WARNING: unable to register hook\n", __func__); } static void socket_hhook_deregister(int subtype) { if (hhook_head_deregister(V_socket_hhh[subtype]) != 0) printf("%s: WARNING: unable to deregister hook\n", __func__); } static void socket_vnet_init(const void *unused __unused) { int i; /* We expect a contiguous range */ for (i = 0; i <= HHOOK_SOCKET_LAST; i++) socket_hhook_register(i); } VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_vnet_init, NULL); static void socket_vnet_uninit(const void *unused __unused) { int i; for (i = 0; i <= HHOOK_SOCKET_LAST; i++) socket_hhook_deregister(i); } VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_vnet_uninit, NULL); #endif /* SOCKET_HHOOK */ /* * Initialise maxsockets. This SYSINIT must be run after * tunable_mbinit(). */ static void init_maxsockets(void *ignored) { TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); maxsockets = imax(maxsockets, maxfiles); } SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); /* * Sysctl to get and set the maximum global sockets limit. Notify protocols * of the change so that they can update their dependent limits as required. */ static int sysctl_maxsockets(SYSCTL_HANDLER_ARGS) { int error, newmaxsockets; newmaxsockets = maxsockets; error = sysctl_handle_int(oidp, &newmaxsockets, 0, req); if (error == 0 && req->newptr && newmaxsockets != maxsockets) { if (newmaxsockets > maxsockets && newmaxsockets <= maxfiles) { maxsockets = newmaxsockets; EVENTHANDLER_INVOKE(maxsockets_change); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets, CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, &maxsockets, 0, sysctl_maxsockets, "IU", "Maximum number of sockets available"); /* * Socket operation routines. These routines are called by the routines in * sys_socket.c or from a system process, and implement the semantics of * socket operations by switching out to the protocol specific routines. */ /* * Get a socket structure from our zone, and initialize it. Note that it * would probably be better to allocate socket and PCB at the same time, but * I'm not convinced that all the protocols can be easily modified to do * this. * * soalloc() returns a socket with a ref count of 0. */ static struct socket * soalloc(struct vnet *vnet) { struct socket *so; so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO); if (so == NULL) return (NULL); #ifdef MAC if (mac_socket_init(so, M_NOWAIT) != 0) { uma_zfree(socket_zone, so); return (NULL); } #endif if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) { uma_zfree(socket_zone, so); return (NULL); } /* * The socket locking protocol allows to lock 2 sockets at a time, * however, the first one must be a listening socket. WITNESS lacks * a feature to change class of an existing lock, so we use DUPOK. */ mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK); mtx_init(&so->so_snd_mtx, "so_snd", NULL, MTX_DEF); mtx_init(&so->so_rcv_mtx, "so_rcv", NULL, MTX_DEF); so->so_rcv.sb_sel = &so->so_rdsel; so->so_snd.sb_sel = &so->so_wrsel; sx_init(&so->so_snd_sx, "so_snd_sx"); sx_init(&so->so_rcv_sx, "so_rcv_sx"); TAILQ_INIT(&so->so_snd.sb_aiojobq); TAILQ_INIT(&so->so_rcv.sb_aiojobq); TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so); TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so); #ifdef VIMAGE VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p", __func__, __LINE__, so)); so->so_vnet = vnet; #endif #ifdef SOCKET_HHOOK /* We shouldn't need the so_global_mtx */ if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) { /* Do we need more comprehensive error returns? */ uma_zfree(socket_zone, so); return (NULL); } #endif mtx_lock(&so_global_mtx); so->so_gencnt = ++so_gencnt; ++numopensockets; #ifdef VIMAGE vnet->vnet_sockcnt++; #endif mtx_unlock(&so_global_mtx); return (so); } /* * Free the storage associated with a socket at the socket layer, tear down * locks, labels, etc. All protocol state is assumed already to have been * torn down (and possibly never set up) by the caller. */ void sodealloc(struct socket *so) { KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count)); KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL")); mtx_lock(&so_global_mtx); so->so_gencnt = ++so_gencnt; --numopensockets; /* Could be below, but faster here. */ #ifdef VIMAGE VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p", __func__, __LINE__, so)); so->so_vnet->vnet_sockcnt--; #endif mtx_unlock(&so_global_mtx); #ifdef MAC mac_socket_destroy(so); #endif #ifdef SOCKET_HHOOK hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE); #endif khelp_destroy_osd(&so->osd); if (SOLISTENING(so)) { if (so->sol_accept_filter != NULL) accept_filt_setopt(so, NULL); } else { if (so->so_rcv.sb_hiwat) (void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); if (so->so_snd.sb_hiwat) (void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); sx_destroy(&so->so_snd_sx); sx_destroy(&so->so_rcv_sx); mtx_destroy(&so->so_snd_mtx); mtx_destroy(&so->so_rcv_mtx); } crfree(so->so_cred); mtx_destroy(&so->so_lock); uma_zfree(socket_zone, so); } /* * socreate returns a socket with a ref count of 1 and a file descriptor * reference. The socket should be closed with soclose(). */ int socreate(int dom, struct socket **aso, int type, int proto, struct ucred *cred, struct thread *td) { struct protosw *prp; struct socket *so; int error; /* * XXX: divert(4) historically abused PF_INET. Keep this compatibility * shim until all applications have been updated. */ if (__predict_false(dom == PF_INET && type == SOCK_RAW && proto == IPPROTO_DIVERT)) { dom = PF_DIVERT; printf("%s uses obsolete way to create divert(4) socket\n", td->td_proc->p_comm); } prp = pffindproto(dom, type, proto); if (prp == NULL) { /* No support for domain. */ if (pffinddomain(dom) == NULL) return (EAFNOSUPPORT); /* No support for socket type. */ if (proto == 0 && type != 0) return (EPROTOTYPE); return (EPROTONOSUPPORT); } MPASS(prp->pr_attach); if ((prp->pr_flags & PR_CAPATTACH) == 0) { if (CAP_TRACING(td)) ktrcapfail(CAPFAIL_PROTO, &proto); if (IN_CAPABILITY_MODE(td)) return (ECAPMODE); } if (prison_check_af(cred, prp->pr_domain->dom_family) != 0) return (EPROTONOSUPPORT); so = soalloc(CRED_TO_VNET(cred)); if (so == NULL) return (ENOBUFS); so->so_type = type; so->so_cred = crhold(cred); if ((prp->pr_domain->dom_family == PF_INET) || (prp->pr_domain->dom_family == PF_INET6) || (prp->pr_domain->dom_family == PF_ROUTE)) so->so_fibnum = td->td_proc->p_fibnum; else so->so_fibnum = 0; so->so_proto = prp; #ifdef MAC mac_socket_create(cred, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); if ((prp->pr_flags & PR_SOCKBUF) == 0) { so->so_snd.sb_mtx = &so->so_snd_mtx; so->so_rcv.sb_mtx = &so->so_rcv_mtx; } /* * Auto-sizing of socket buffers is managed by the protocols and * the appropriate flags must be set in the pru_attach function. */ CURVNET_SET(so->so_vnet); error = prp->pr_attach(so, proto, td); CURVNET_RESTORE(); if (error) { sodealloc(so); return (error); } soref(so); *aso = so; return (0); } #ifdef REGRESSION static int regression_sonewconn_earlytest = 1; SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW, ®ression_sonewconn_earlytest, 0, "Perform early sonewconn limit test"); #endif static int sooverprio = LOG_DEBUG; SYSCTL_INT(_kern_ipc, OID_AUTO, sooverprio, CTLFLAG_RW, &sooverprio, 0, "Log priority for listen socket overflows: 0..7 or -1 to disable"); static struct timeval overinterval = { 60, 0 }; SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW, &overinterval, "Delay in seconds between warnings for listen socket overflows"); /* * When an attempt at a new connection is noted on a socket which supports * accept(2), the protocol has two options: * 1) Call legacy sonewconn() function, which would call protocol attach * method, same as used for socket(2). * 2) Call solisten_clone(), do attach that is specific to a cloned connection, * and then call solisten_enqueue(). * * Note: the ref count on the socket is 0 on return. */ struct socket * solisten_clone(struct socket *head) { struct sbuf descrsb; struct socket *so; int len, overcount; u_int qlen; const char localprefix[] = "local:"; char descrbuf[SUNPATHLEN + sizeof(localprefix)]; #if defined(INET6) char addrbuf[INET6_ADDRSTRLEN]; #elif defined(INET) char addrbuf[INET_ADDRSTRLEN]; #endif bool dolog, over; SOLISTEN_LOCK(head); over = (head->sol_qlen > 3 * head->sol_qlimit / 2); #ifdef REGRESSION if (regression_sonewconn_earlytest && over) { #else if (over) { #endif head->sol_overcount++; dolog = (sooverprio >= 0) && !!ratecheck(&head->sol_lastover, &overinterval); /* * If we're going to log, copy the overflow count and queue * length from the listen socket before dropping the lock. * Also, reset the overflow count. */ if (dolog) { overcount = head->sol_overcount; head->sol_overcount = 0; qlen = head->sol_qlen; } SOLISTEN_UNLOCK(head); if (dolog) { /* * Try to print something descriptive about the * socket for the error message. */ sbuf_new(&descrsb, descrbuf, sizeof(descrbuf), SBUF_FIXEDLEN); switch (head->so_proto->pr_domain->dom_family) { #if defined(INET) || defined(INET6) #ifdef INET case AF_INET: #endif #ifdef INET6 case AF_INET6: if (head->so_proto->pr_domain->dom_family == AF_INET6 || (sotoinpcb(head)->inp_inc.inc_flags & INC_ISIPV6)) { ip6_sprintf(addrbuf, &sotoinpcb(head)->inp_inc.inc6_laddr); sbuf_printf(&descrsb, "[%s]", addrbuf); } else #endif { #ifdef INET inet_ntoa_r( sotoinpcb(head)->inp_inc.inc_laddr, addrbuf); sbuf_cat(&descrsb, addrbuf); #endif } sbuf_printf(&descrsb, ":%hu (proto %u)", ntohs(sotoinpcb(head)->inp_inc.inc_lport), head->so_proto->pr_protocol); break; #endif /* INET || INET6 */ case AF_UNIX: sbuf_cat(&descrsb, localprefix); if (sotounpcb(head)->unp_addr != NULL) len = sotounpcb(head)->unp_addr->sun_len - offsetof(struct sockaddr_un, sun_path); else len = 0; if (len > 0) sbuf_bcat(&descrsb, sotounpcb(head)->unp_addr->sun_path, len); else sbuf_cat(&descrsb, "(unknown)"); break; } /* * If we can't print something more specific, at least * print the domain name. */ if (sbuf_finish(&descrsb) != 0 || sbuf_len(&descrsb) <= 0) { sbuf_clear(&descrsb); sbuf_cat(&descrsb, head->so_proto->pr_domain->dom_name ?: "unknown"); sbuf_finish(&descrsb); } KASSERT(sbuf_len(&descrsb) > 0, ("%s: sbuf creation failed", __func__)); /* * Preserve the historic listen queue overflow log * message, that starts with "sonewconn:". It has * been known to sysadmins for years and also test * sys/kern/sonewconn_overflow checks for it. */ if (head->so_cred == 0) { log(LOG_PRI(sooverprio), "sonewconn: pcb %p (%s): " "Listen queue overflow: %i already in " "queue awaiting acceptance (%d " "occurrences)\n", head->so_pcb, sbuf_data(&descrsb), qlen, overcount); } else { log(LOG_PRI(sooverprio), "sonewconn: pcb %p (%s): " "Listen queue overflow: " "%i already in queue awaiting acceptance " "(%d occurrences), euid %d, rgid %d, jail %s\n", head->so_pcb, sbuf_data(&descrsb), qlen, overcount, head->so_cred->cr_uid, head->so_cred->cr_rgid, head->so_cred->cr_prison ? head->so_cred->cr_prison->pr_name : "not_jailed"); } sbuf_delete(&descrsb); overcount = 0; } return (NULL); } SOLISTEN_UNLOCK(head); VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL", __func__, head)); so = soalloc(head->so_vnet); if (so == NULL) { log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " "limit reached or out of memory\n", __func__, head->so_pcb); return (NULL); } so->so_listen = head; so->so_type = head->so_type; /* * POSIX is ambiguous on what options an accept(2)ed socket should * inherit from the listener. Words "create a new socket" may be * interpreted as not inheriting anything. Best programming practice * for application developers is to not rely on such inheritance. * FreeBSD had historically inherited all so_options excluding * SO_ACCEPTCONN, which virtually means all SOL_SOCKET level options, * including those completely irrelevant to a new born socket. For * compatibility with older versions we will inherit a list of * meaningful options. * The crucial bit to inherit is SO_ACCEPTFILTER. We need it present * in the child socket for soisconnected() promoting socket from the * incomplete queue to complete. It will be cleared before the child * gets available to accept(2). */ so->so_options = head->so_options & (SO_ACCEPTFILTER | SO_KEEPALIVE | SO_DONTROUTE | SO_LINGER | SO_OOBINLINE | SO_NOSIGPIPE); so->so_linger = head->so_linger; so->so_state = head->so_state; so->so_fibnum = head->so_fibnum; so->so_proto = head->so_proto; so->so_cred = crhold(head->so_cred); #ifdef SOCKET_HHOOK if (V_socket_hhh[HHOOK_SOCKET_NEWCONN]->hhh_nhooks > 0) { if (hhook_run_socket(so, head, HHOOK_SOCKET_NEWCONN)) { sodealloc(so); log(LOG_DEBUG, "%s: hhook run failed\n", __func__); return (NULL); } } #endif #ifdef MAC mac_socket_newconn(head, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); VNET_SO_ASSERT(head); if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", __func__, head->so_pcb); return (NULL); } so->so_rcv.sb_lowat = head->sol_sbrcv_lowat; so->so_snd.sb_lowat = head->sol_sbsnd_lowat; so->so_rcv.sb_timeo = head->sol_sbrcv_timeo; so->so_snd.sb_timeo = head->sol_sbsnd_timeo; so->so_rcv.sb_flags = head->sol_sbrcv_flags & SB_AUTOSIZE; so->so_snd.sb_flags = head->sol_sbsnd_flags & SB_AUTOSIZE; if ((so->so_proto->pr_flags & PR_SOCKBUF) == 0) { so->so_snd.sb_mtx = &so->so_snd_mtx; so->so_rcv.sb_mtx = &so->so_rcv_mtx; } return (so); } /* Connstatus may be 0 or SS_ISCONNECTED. */ struct socket * sonewconn(struct socket *head, int connstatus) { struct socket *so; if ((so = solisten_clone(head)) == NULL) return (NULL); if (so->so_proto->pr_attach(so, 0, NULL) != 0) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: pr_attach() failed\n", __func__, head->so_pcb); return (NULL); } (void)solisten_enqueue(so, connstatus); return (so); } /* * Enqueue socket cloned by solisten_clone() to the listen queue of the * listener it has been cloned from. * * Return 'true' if socket landed on complete queue, otherwise 'false'. */ bool solisten_enqueue(struct socket *so, int connstatus) { struct socket *head = so->so_listen; MPASS(refcount_load(&so->so_count) == 0); refcount_init(&so->so_count, 1); SOLISTEN_LOCK(head); if (head->sol_accept_filter != NULL) connstatus = 0; so->so_state |= connstatus; soref(head); /* A socket on (in)complete queue refs head. */ if (connstatus) { TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); so->so_qstate = SQ_COMP; head->sol_qlen++; solisten_wakeup(head); /* unlocks */ return (true); } else { /* * Keep removing sockets from the head until there's room for * us to insert on the tail. In pre-locking revisions, this * was a simple if(), but as we could be racing with other * threads and soabort() requires dropping locks, we must * loop waiting for the condition to be true. */ while (head->sol_incqlen > head->sol_qlimit) { struct socket *sp; sp = TAILQ_FIRST(&head->sol_incomp); TAILQ_REMOVE(&head->sol_incomp, sp, so_list); head->sol_incqlen--; SOCK_LOCK(sp); sp->so_qstate = SQ_NONE; sp->so_listen = NULL; SOCK_UNLOCK(sp); sorele_locked(head); /* does SOLISTEN_UNLOCK, head stays */ soabort(sp); SOLISTEN_LOCK(head); } TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list); so->so_qstate = SQ_INCOMP; head->sol_incqlen++; SOLISTEN_UNLOCK(head); return (false); } } #if defined(SCTP) || defined(SCTP_SUPPORT) /* * Socket part of sctp_peeloff(). Detach a new socket from an * association. The new socket is returned with a reference. * * XXXGL: reduce copy-paste with solisten_clone(). */ struct socket * sopeeloff(struct socket *head) { struct socket *so; VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p", __func__, __LINE__, head)); so = soalloc(head->so_vnet); if (so == NULL) { log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " "limit reached or out of memory\n", __func__, head->so_pcb); return (NULL); } so->so_type = head->so_type; so->so_options = head->so_options; so->so_linger = head->so_linger; so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED; so->so_fibnum = head->so_fibnum; so->so_proto = head->so_proto; so->so_cred = crhold(head->so_cred); #ifdef MAC mac_socket_newconn(head, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); VNET_SO_ASSERT(head); if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", __func__, head->so_pcb); return (NULL); } if ((*so->so_proto->pr_attach)(so, 0, NULL)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n", __func__, head->so_pcb); return (NULL); } so->so_rcv.sb_lowat = head->so_rcv.sb_lowat; so->so_snd.sb_lowat = head->so_snd.sb_lowat; so->so_rcv.sb_timeo = head->so_rcv.sb_timeo; so->so_snd.sb_timeo = head->so_snd.sb_timeo; so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE; so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE; if ((so->so_proto->pr_flags & PR_SOCKBUF) == 0) { so->so_snd.sb_mtx = &so->so_snd_mtx; so->so_rcv.sb_mtx = &so->so_rcv_mtx; } soref(so); return (so); } #endif /* SCTP */ int sobind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_bind(so, nam, td); CURVNET_RESTORE(); return (error); } int sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_bindat(fd, so, nam, td); CURVNET_RESTORE(); return (error); } /* * solisten() transitions a socket from a non-listening state to a listening * state, but can also be used to update the listen queue depth on an * existing listen socket. The protocol will call back into the sockets * layer using solisten_proto_check() and solisten_proto() to check and set * socket-layer listen state. Call backs are used so that the protocol can * acquire both protocol and socket layer locks in whatever order is required * by the protocol. * * Protocol implementors are advised to hold the socket lock across the * socket-layer test and set to avoid races at the socket layer. */ int solisten(struct socket *so, int backlog, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_listen(so, backlog, td); CURVNET_RESTORE(); return (error); } /* * Prepare for a call to solisten_proto(). Acquire all socket buffer locks in * order to interlock with socket I/O. */ int solisten_proto_check(struct socket *so) { SOCK_LOCK_ASSERT(so); if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) != 0) return (EINVAL); /* * Sleeping is not permitted here, so simply fail if userspace is * attempting to transmit or receive on the socket. This kind of * transient failure is not ideal, but it should occur only if userspace * is misusing the socket interfaces. */ if (!sx_try_xlock(&so->so_snd_sx)) return (EAGAIN); if (!sx_try_xlock(&so->so_rcv_sx)) { sx_xunlock(&so->so_snd_sx); return (EAGAIN); } mtx_lock(&so->so_snd_mtx); mtx_lock(&so->so_rcv_mtx); /* Interlock with soo_aio_queue() and KTLS. */ if (!SOLISTENING(so)) { bool ktls; #ifdef KERN_TLS ktls = so->so_snd.sb_tls_info != NULL || so->so_rcv.sb_tls_info != NULL; #else ktls = false; #endif if (ktls || (so->so_snd.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0 || (so->so_rcv.sb_flags & (SB_AIO | SB_AIO_RUNNING)) != 0) { solisten_proto_abort(so); return (EINVAL); } } return (0); } /* * Undo the setup done by solisten_proto_check(). */ void solisten_proto_abort(struct socket *so) { mtx_unlock(&so->so_snd_mtx); mtx_unlock(&so->so_rcv_mtx); sx_xunlock(&so->so_snd_sx); sx_xunlock(&so->so_rcv_sx); } void solisten_proto(struct socket *so, int backlog) { int sbrcv_lowat, sbsnd_lowat; u_int sbrcv_hiwat, sbsnd_hiwat; short sbrcv_flags, sbsnd_flags; sbintime_t sbrcv_timeo, sbsnd_timeo; SOCK_LOCK_ASSERT(so); KASSERT((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0, ("%s: bad socket state %p", __func__, so)); if (SOLISTENING(so)) goto listening; /* * Change this socket to listening state. */ sbrcv_lowat = so->so_rcv.sb_lowat; sbsnd_lowat = so->so_snd.sb_lowat; sbrcv_hiwat = so->so_rcv.sb_hiwat; sbsnd_hiwat = so->so_snd.sb_hiwat; sbrcv_flags = so->so_rcv.sb_flags; sbsnd_flags = so->so_snd.sb_flags; sbrcv_timeo = so->so_rcv.sb_timeo; sbsnd_timeo = so->so_snd.sb_timeo; #ifdef MAC mac_socketpeer_label_free(so->so_peerlabel); #endif if (!(so->so_proto->pr_flags & PR_SOCKBUF)) { sbdestroy(so, SO_SND); sbdestroy(so, SO_RCV); } #ifdef INVARIANTS bzero(&so->so_rcv, sizeof(struct socket) - offsetof(struct socket, so_rcv)); #endif so->sol_sbrcv_lowat = sbrcv_lowat; so->sol_sbsnd_lowat = sbsnd_lowat; so->sol_sbrcv_hiwat = sbrcv_hiwat; so->sol_sbsnd_hiwat = sbsnd_hiwat; so->sol_sbrcv_flags = sbrcv_flags; so->sol_sbsnd_flags = sbsnd_flags; so->sol_sbrcv_timeo = sbrcv_timeo; so->sol_sbsnd_timeo = sbsnd_timeo; so->sol_qlen = so->sol_incqlen = 0; TAILQ_INIT(&so->sol_incomp); TAILQ_INIT(&so->sol_comp); so->sol_accept_filter = NULL; so->sol_accept_filter_arg = NULL; so->sol_accept_filter_str = NULL; so->sol_upcall = NULL; so->sol_upcallarg = NULL; so->so_options |= SO_ACCEPTCONN; listening: if (backlog < 0 || backlog > somaxconn) backlog = somaxconn; so->sol_qlimit = backlog; mtx_unlock(&so->so_snd_mtx); mtx_unlock(&so->so_rcv_mtx); sx_xunlock(&so->so_snd_sx); sx_xunlock(&so->so_rcv_sx); } /* * Wakeup listeners/subsystems once we have a complete connection. * Enters with lock, returns unlocked. */ void solisten_wakeup(struct socket *sol) { if (sol->sol_upcall != NULL) (void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT); else { selwakeuppri(&sol->so_rdsel, PSOCK); KNOTE_LOCKED(&sol->so_rdsel.si_note, 0); } SOLISTEN_UNLOCK(sol); wakeup_one(&sol->sol_comp); if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL) pgsigio(&sol->so_sigio, SIGIO, 0); } /* * Return single connection off a listening socket queue. Main consumer of * the function is kern_accept4(). Some modules, that do their own accept * management also use the function. The socket reference held by the * listen queue is handed to the caller. * * Listening socket must be locked on entry and is returned unlocked on * return. * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT. */ int solisten_dequeue(struct socket *head, struct socket **ret, int flags) { struct socket *so; int error; SOLISTEN_LOCK_ASSERT(head); while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) && head->so_error == 0) { error = msleep(&head->sol_comp, SOCK_MTX(head), PSOCK | PCATCH, "accept", 0); if (error != 0) { SOLISTEN_UNLOCK(head); return (error); } } if (head->so_error) { error = head->so_error; head->so_error = 0; } else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp)) error = EWOULDBLOCK; else error = 0; if (error) { SOLISTEN_UNLOCK(head); return (error); } so = TAILQ_FIRST(&head->sol_comp); SOCK_LOCK(so); KASSERT(so->so_qstate == SQ_COMP, ("%s: so %p not SQ_COMP", __func__, so)); head->sol_qlen--; so->so_qstate = SQ_NONE; so->so_listen = NULL; TAILQ_REMOVE(&head->sol_comp, so, so_list); if (flags & ACCEPT4_INHERIT) so->so_state |= (head->so_state & SS_NBIO); else so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0; SOCK_UNLOCK(so); sorele_locked(head); *ret = so; return (0); } static struct so_splice * so_splice_alloc(off_t max) { struct so_splice *sp; sp = uma_zalloc(splice_zone, M_WAITOK); sp->src = NULL; sp->dst = NULL; sp->max = max > 0 ? max : -1; do { sp->wq_index = atomic_fetchadd_32(&splice_index, 1) % (mp_maxid + 1); } while (CPU_ABSENT(sp->wq_index)); sp->state = SPLICE_IDLE; TIMEOUT_TASK_INIT(taskqueue_thread, &sp->timeout, 0, so_splice_timeout, sp); return (sp); } static void so_splice_free(struct so_splice *sp) { KASSERT(sp->state == SPLICE_CLOSED, ("so_splice_free: sp %p not closed", sp)); uma_zfree(splice_zone, sp); } static void so_splice_timeout(void *arg, int pending __unused) { struct so_splice *sp; sp = arg; (void)so_unsplice(sp->src, true); } /* * Splice the output from so to the input of so2. */ static int so_splice(struct socket *so, struct socket *so2, struct splice *splice) { struct so_splice *sp; int error; if (splice->sp_max < 0) return (EINVAL); /* Handle only TCP for now; TODO: other streaming protos */ if (so->so_proto->pr_protocol != IPPROTO_TCP || so2->so_proto->pr_protocol != IPPROTO_TCP) return (EPROTONOSUPPORT); if (so->so_vnet != so2->so_vnet) return (EINVAL); /* so_splice_xfer() assumes that we're using these implementations. */ KASSERT(so->so_proto->pr_sosend == sosend_generic, ("so_splice: sosend not sosend_generic")); KASSERT(so2->so_proto->pr_soreceive == soreceive_generic || so2->so_proto->pr_soreceive == soreceive_stream, ("so_splice: soreceive not soreceive_generic/stream")); sp = so_splice_alloc(splice->sp_max); so->so_splice_sent = 0; sp->src = so; sp->dst = so2; error = 0; SOCK_LOCK(so); if (SOLISTENING(so)) error = EINVAL; else if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING)) == 0) error = ENOTCONN; else if (so->so_splice != NULL) error = EBUSY; if (error != 0) { SOCK_UNLOCK(so); uma_zfree(splice_zone, sp); return (error); } soref(so); so->so_splice = sp; SOCK_RECVBUF_LOCK(so); so->so_rcv.sb_flags |= SB_SPLICED; SOCK_RECVBUF_UNLOCK(so); SOCK_UNLOCK(so); error = 0; SOCK_LOCK(so2); if (SOLISTENING(so2)) error = EINVAL; else if ((so2->so_state & (SS_ISCONNECTED | SS_ISCONNECTING)) == 0) error = ENOTCONN; else if (so2->so_splice_back != NULL) error = EBUSY; if (error != 0) { SOCK_UNLOCK(so2); SOCK_LOCK(so); so->so_splice = NULL; SOCK_RECVBUF_LOCK(so); so->so_rcv.sb_flags &= ~SB_SPLICED; SOCK_RECVBUF_UNLOCK(so); SOCK_UNLOCK(so); sorele(so); uma_zfree(splice_zone, sp); return (error); } soref(so2); so2->so_splice_back = sp; SOCK_SENDBUF_LOCK(so2); so2->so_snd.sb_flags |= SB_SPLICED; mtx_lock(&sp->mtx); SOCK_SENDBUF_UNLOCK(so2); SOCK_UNLOCK(so2); if (splice->sp_idle.tv_sec != 0 || splice->sp_idle.tv_usec != 0) { taskqueue_enqueue_timeout_sbt(taskqueue_thread, &sp->timeout, tvtosbt(splice->sp_idle), 0, C_PREL(4)); } /* * Transfer any data already present in the socket buffer. */ sp->state = SPLICE_QUEUED; so_splice_xfer(sp); return (0); } static int so_unsplice(struct socket *so, bool timeout) { struct socket *so2; struct so_splice *sp; bool drain; /* * First unset SB_SPLICED and hide the splice structure so that * wakeup routines will stop enqueuing work. This also ensures that * a only a single thread will proceed with the unsplice. */ SOCK_LOCK(so); if (SOLISTENING(so)) { SOCK_UNLOCK(so); return (EINVAL); } SOCK_RECVBUF_LOCK(so); if ((so->so_rcv.sb_flags & SB_SPLICED) == 0) { SOCK_RECVBUF_UNLOCK(so); SOCK_UNLOCK(so); return (ENOTCONN); } so->so_rcv.sb_flags &= ~SB_SPLICED; sp = so->so_splice; so->so_splice = NULL; SOCK_RECVBUF_UNLOCK(so); SOCK_UNLOCK(so); so2 = sp->dst; SOCK_LOCK(so2); KASSERT(!SOLISTENING(so2), ("%s: so2 is listening", __func__)); SOCK_SENDBUF_LOCK(so2); KASSERT((so2->so_snd.sb_flags & SB_SPLICED) != 0, ("%s: so2 is not spliced", __func__)); KASSERT(so2->so_splice_back == sp, ("%s: so_splice_back != sp", __func__)); so2->so_snd.sb_flags &= ~SB_SPLICED; so2->so_splice_back = NULL; SOCK_SENDBUF_UNLOCK(so2); SOCK_UNLOCK(so2); /* * No new work is being enqueued. The worker thread might be * splicing data right now, in which case we want to wait for it to * finish before proceeding. */ mtx_lock(&sp->mtx); switch (sp->state) { case SPLICE_QUEUED: case SPLICE_RUNNING: sp->state = SPLICE_CLOSING; while (sp->state == SPLICE_CLOSING) msleep(sp, &sp->mtx, PSOCK, "unsplice", 0); break; case SPLICE_IDLE: case SPLICE_EXCEPTION: sp->state = SPLICE_CLOSED; break; default: __assert_unreachable(); } if (!timeout) { drain = taskqueue_cancel_timeout(taskqueue_thread, &sp->timeout, NULL) != 0; } else { drain = false; } mtx_unlock(&sp->mtx); if (drain) taskqueue_drain_timeout(taskqueue_thread, &sp->timeout); /* * Now we hold the sole reference to the splice structure. * Clean up: signal userspace and release socket references. */ sorwakeup(so); CURVNET_SET(so->so_vnet); sorele(so); sowwakeup(so2); sorele(so2); CURVNET_RESTORE(); so_splice_free(sp); return (0); } /* * Free socket upon release of the very last reference. */ static void sofree(struct socket *so) { struct protosw *pr = so->so_proto; SOCK_LOCK_ASSERT(so); KASSERT(refcount_load(&so->so_count) == 0, ("%s: so %p has references", __func__, so)); KASSERT(SOLISTENING(so) || so->so_qstate == SQ_NONE, ("%s: so %p is on listen queue", __func__, so)); KASSERT(SOLISTENING(so) || (so->so_rcv.sb_flags & SB_SPLICED) == 0, ("%s: so %p rcvbuf is spliced", __func__, so)); KASSERT(SOLISTENING(so) || (so->so_snd.sb_flags & SB_SPLICED) == 0, ("%s: so %p sndbuf is spliced", __func__, so)); KASSERT(so->so_splice == NULL && so->so_splice_back == NULL, ("%s: so %p has spliced data", __func__, so)); SOCK_UNLOCK(so); if (so->so_dtor != NULL) so->so_dtor(so); VNET_SO_ASSERT(so); if (pr->pr_detach != NULL) pr->pr_detach(so); /* * From this point on, we assume that no other references to this * socket exist anywhere else in the stack. Therefore, no locks need * to be acquired or held. */ if (!(pr->pr_flags & PR_SOCKBUF) && !SOLISTENING(so)) { sbdestroy(so, SO_SND); sbdestroy(so, SO_RCV); } seldrain(&so->so_rdsel); seldrain(&so->so_wrsel); knlist_destroy(&so->so_rdsel.si_note); knlist_destroy(&so->so_wrsel.si_note); sodealloc(so); } /* * Release a reference on a socket while holding the socket lock. * Unlocks the socket lock before returning. */ void sorele_locked(struct socket *so) { SOCK_LOCK_ASSERT(so); if (refcount_release(&so->so_count)) sofree(so); else SOCK_UNLOCK(so); } /* * Close a socket on last file table reference removal. Initiate disconnect * if connected. Free socket when disconnect complete. * * This function will sorele() the socket. Note that soclose() may be called * prior to the ref count reaching zero. The actual socket structure will * not be freed until the ref count reaches zero. */ int soclose(struct socket *so) { struct accept_queue lqueue; int error = 0; bool listening, last __diagused; CURVNET_SET(so->so_vnet); funsetown(&so->so_sigio); if (so->so_state & SS_ISCONNECTED) { if ((so->so_state & SS_ISDISCONNECTING) == 0) { error = sodisconnect(so); if (error) { if (error == ENOTCONN) error = 0; goto drop; } } if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) { if ((so->so_state & SS_ISDISCONNECTING) && (so->so_state & SS_NBIO)) goto drop; while (so->so_state & SS_ISCONNECTED) { error = tsleep(&so->so_timeo, PSOCK | PCATCH, "soclos", so->so_linger * hz); if (error) break; } } } drop: if (so->so_proto->pr_close != NULL) so->so_proto->pr_close(so); SOCK_LOCK(so); if ((listening = SOLISTENING(so))) { struct socket *sp; TAILQ_INIT(&lqueue); TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list); TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list); so->sol_qlen = so->sol_incqlen = 0; TAILQ_FOREACH(sp, &lqueue, so_list) { SOCK_LOCK(sp); sp->so_qstate = SQ_NONE; sp->so_listen = NULL; SOCK_UNLOCK(sp); last = refcount_release(&so->so_count); KASSERT(!last, ("%s: released last reference for %p", __func__, so)); } } sorele_locked(so); if (listening) { struct socket *sp, *tsp; TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) soabort(sp); } CURVNET_RESTORE(); return (error); } /* * soabort() is used to abruptly tear down a connection, such as when a * resource limit is reached (listen queue depth exceeded), or if a listen * socket is closed while there are sockets waiting to be accepted. * * This interface is tricky, because it is called on an unreferenced socket, * and must be called only by a thread that has actually removed the socket * from the listen queue it was on. Likely this thread holds the last * reference on the socket and soabort() will proceed with sofree(). But * it might be not the last, as the sockets on the listen queues are seen * from the protocol side. * * This interface will call into the protocol code, so must not be called * with any socket locks held. Protocols do call it while holding their own * recursible protocol mutexes, but this is something that should be subject * to review in the future. * * Usually socket should have a single reference left, but this is not a * requirement. In the past, when we have had named references for file * descriptor and protocol, we asserted that none of them are being held. */ void soabort(struct socket *so) { VNET_SO_ASSERT(so); if (so->so_proto->pr_abort != NULL) so->so_proto->pr_abort(so); SOCK_LOCK(so); sorele_locked(so); } int soaccept(struct socket *so, struct sockaddr *sa) { #ifdef INVARIANTS u_char len = sa->sa_len; #endif int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_accept(so, sa); KASSERT(sa->sa_len <= len, ("%s: protocol %p sockaddr overflow", __func__, so->so_proto)); CURVNET_RESTORE(); return (error); } int sopeeraddr(struct socket *so, struct sockaddr *sa) { #ifdef INVARIANTS u_char len = sa->sa_len; #endif int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_peeraddr(so, sa); KASSERT(sa->sa_len <= len, ("%s: protocol %p sockaddr overflow", __func__, so->so_proto)); CURVNET_RESTORE(); return (error); } int sosockaddr(struct socket *so, struct sockaddr *sa) { #ifdef INVARIANTS u_char len = sa->sa_len; #endif int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_sockaddr(so, sa); KASSERT(sa->sa_len <= len, ("%s: protocol %p sockaddr overflow", __func__, so->so_proto)); CURVNET_RESTORE(); return (error); } int soconnect(struct socket *so, struct sockaddr *nam, struct thread *td) { return (soconnectat(AT_FDCWD, so, nam, td)); } int soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { int error; CURVNET_SET(so->so_vnet); /* * If protocol is connection-based, can only connect once. * Otherwise, if connected, try to disconnect first. This allows * user to disconnect by connecting to, e.g., a null address. * * Note, this check is racy and may need to be re-evaluated at the * protocol layer. */ if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && ((so->so_proto->pr_flags & PR_CONNREQUIRED) || (error = sodisconnect(so)))) { error = EISCONN; } else { /* * Prevent accumulated error from previous connection from * biting us. */ so->so_error = 0; if (fd == AT_FDCWD) { error = so->so_proto->pr_connect(so, nam, td); } else { error = so->so_proto->pr_connectat(fd, so, nam, td); } } CURVNET_RESTORE(); return (error); } int soconnect2(struct socket *so1, struct socket *so2) { int error; CURVNET_SET(so1->so_vnet); error = so1->so_proto->pr_connect2(so1, so2); CURVNET_RESTORE(); return (error); } int sodisconnect(struct socket *so) { int error; if ((so->so_state & SS_ISCONNECTED) == 0) return (ENOTCONN); if (so->so_state & SS_ISDISCONNECTING) return (EALREADY); VNET_SO_ASSERT(so); error = so->so_proto->pr_disconnect(so); return (error); } int sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { long space; ssize_t resid; int clen = 0, error, dontroute; KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM")); KASSERT(so->so_proto->pr_flags & PR_ATOMIC, ("sosend_dgram: !PR_ATOMIC")); if (uio != NULL) resid = uio->uio_resid; else resid = top->m_pkthdr.len; /* * In theory resid should be unsigned. However, space must be * signed, as it might be less than 0 if we over-committed, and we * must use a signed comparison of space and resid. On the other * hand, a negative resid causes us to loop sending 0-length * segments to the protocol. */ if (resid < 0) { error = EINVAL; goto out; } dontroute = (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0; if (td != NULL) td->td_ru.ru_msgsnd++; if (control != NULL) clen = control->m_len; SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_state & SBS_CANTSENDMORE) { SOCKBUF_UNLOCK(&so->so_snd); error = EPIPE; goto out; } if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto out; } if ((so->so_state & SS_ISCONNECTED) == 0) { /* * `sendto' and `sendmsg' is allowed on a connection-based * socket if it supports implied connect. Return ENOTCONN if * not connected and no address is supplied. */ if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { if (!(resid == 0 && clen != 0)) { SOCKBUF_UNLOCK(&so->so_snd); error = ENOTCONN; goto out; } } else if (addr == NULL) { if (so->so_proto->pr_flags & PR_CONNREQUIRED) error = ENOTCONN; else error = EDESTADDRREQ; SOCKBUF_UNLOCK(&so->so_snd); goto out; } } /* * Do we need MSG_OOB support in SOCK_DGRAM? Signs here may be a * problem and need fixing. */ space = sbspace(&so->so_snd); if (flags & MSG_OOB) space += 1024; space -= clen; SOCKBUF_UNLOCK(&so->so_snd); if (resid > space) { error = EMSGSIZE; goto out; } if (uio == NULL) { resid = 0; if (flags & MSG_EOR) top->m_flags |= M_EOR; } else { /* * Copy the data from userland into a mbuf chain. * If no data is to be copied in, a single empty mbuf * is returned. */ top = m_uiotombuf(uio, M_WAITOK, space, max_hdr, (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0))); if (top == NULL) { error = EFAULT; /* only possible error */ goto out; } space -= resid - uio->uio_resid; resid = uio->uio_resid; } KASSERT(resid == 0, ("sosend_dgram: resid != 0")); /* * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock * than with. */ if (dontroute) { SOCK_LOCK(so); so->so_options |= SO_DONTROUTE; SOCK_UNLOCK(so); } /* * XXX all the SBS_CANTSENDMORE checks previously done could be out * of date. We could have received a reset packet in an interrupt or * maybe we slept while doing page faults in uiomove() etc. We could * probably recheck again inside the locking protection here, but * there are probably other places that this also happens. We must * rethink this. */ VNET_SO_ASSERT(so); error = so->so_proto->pr_send(so, (flags & MSG_OOB) ? PRUS_OOB : /* * If the user set MSG_EOF, the protocol understands this flag and * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND. */ ((flags & MSG_EOF) && (so->so_proto->pr_flags & PR_IMPLOPCL) && (resid <= 0)) ? PRUS_EOF : /* If there is more to send set PRUS_MORETOCOME */ (flags & MSG_MORETOCOME) || (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, top, addr, control, td); if (dontroute) { SOCK_LOCK(so); so->so_options &= ~SO_DONTROUTE; SOCK_UNLOCK(so); } clen = 0; control = NULL; top = NULL; out: if (top != NULL) m_freem(top); if (control != NULL) m_freem(control); return (error); } /* * Send on a socket. If send must go all at once and message is larger than * send buffering, then hard error. Lock against other senders. If must go * all at once and not enough room now, then inform user that this would * block and do nothing. Otherwise, if nonblocking, send as much as * possible. The data to be sent is described by "uio" if nonzero, otherwise * by the mbuf chain "top" (which must be null if uio is not). Data provided * in mbuf chain must be small enough to send all at once. * * Returns nonzero on error, timeout or signal; callers must check for short * counts if EINTR/ERESTART are returned. Data and control buffers are freed * on return. */ static int sosend_generic_locked(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { long space; ssize_t resid; int clen = 0, error, dontroute; int atomic = sosendallatonce(so) || top; int pr_send_flag; #ifdef KERN_TLS struct ktls_session *tls; int tls_enq_cnt, tls_send_flag; uint8_t tls_rtype; tls = NULL; tls_rtype = TLS_RLTYPE_APP; #endif SOCK_IO_SEND_ASSERT_LOCKED(so); if (uio != NULL) resid = uio->uio_resid; else if ((top->m_flags & M_PKTHDR) != 0) resid = top->m_pkthdr.len; else resid = m_length(top, NULL); /* * In theory resid should be unsigned. However, space must be * signed, as it might be less than 0 if we over-committed, and we * must use a signed comparison of space and resid. On the other * hand, a negative resid causes us to loop sending 0-length * segments to the protocol. * * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM * type sockets since that's an error. */ if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) { error = EINVAL; goto out; } dontroute = (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && (so->so_proto->pr_flags & PR_ATOMIC); if (td != NULL) td->td_ru.ru_msgsnd++; if (control != NULL) clen = control->m_len; #ifdef KERN_TLS tls_send_flag = 0; tls = ktls_hold(so->so_snd.sb_tls_info); if (tls != NULL) { if (tls->mode == TCP_TLS_MODE_SW) tls_send_flag = PRUS_NOTREADY; if (control != NULL) { struct cmsghdr *cm = mtod(control, struct cmsghdr *); if (clen >= sizeof(*cm) && cm->cmsg_type == TLS_SET_RECORD_TYPE) { tls_rtype = *((uint8_t *)CMSG_DATA(cm)); clen = 0; m_freem(control); control = NULL; atomic = 1; } } if (resid == 0 && !ktls_permit_empty_frames(tls)) { error = EINVAL; goto out; } } #endif restart: do { SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_state & SBS_CANTSENDMORE) { SOCKBUF_UNLOCK(&so->so_snd); error = EPIPE; goto out; } if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto out; } if ((so->so_state & SS_ISCONNECTED) == 0) { /* * `sendto' and `sendmsg' is allowed on a connection- * based socket if it supports implied connect. * Return ENOTCONN if not connected and no address is * supplied. */ if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { if (!(resid == 0 && clen != 0)) { SOCKBUF_UNLOCK(&so->so_snd); error = ENOTCONN; goto out; } } else if (addr == NULL) { SOCKBUF_UNLOCK(&so->so_snd); if (so->so_proto->pr_flags & PR_CONNREQUIRED) error = ENOTCONN; else error = EDESTADDRREQ; goto out; } } space = sbspace(&so->so_snd); if (flags & MSG_OOB) space += 1024; if ((atomic && resid > so->so_snd.sb_hiwat) || clen > so->so_snd.sb_hiwat) { SOCKBUF_UNLOCK(&so->so_snd); error = EMSGSIZE; goto out; } if (space < resid + clen && (atomic || space < so->so_snd.sb_lowat || space < clen)) { if ((so->so_state & SS_NBIO) || (flags & (MSG_NBIO | MSG_DONTWAIT)) != 0) { SOCKBUF_UNLOCK(&so->so_snd); error = EWOULDBLOCK; goto out; } error = sbwait(so, SO_SND); SOCKBUF_UNLOCK(&so->so_snd); if (error) goto out; goto restart; } SOCKBUF_UNLOCK(&so->so_snd); space -= clen; do { if (uio == NULL) { resid = 0; if (flags & MSG_EOR) top->m_flags |= M_EOR; #ifdef KERN_TLS if (tls != NULL) { ktls_frame(top, tls, &tls_enq_cnt, tls_rtype); tls_rtype = TLS_RLTYPE_APP; } #endif } else { /* * Copy the data from userland into a mbuf * chain. If resid is 0, which can happen * only if we have control to send, then * a single empty mbuf is returned. This * is a workaround to prevent protocol send * methods to panic. */ #ifdef KERN_TLS if (tls != NULL) { top = m_uiotombuf(uio, M_WAITOK, space, tls->params.max_frame_len, M_EXTPG | ((flags & MSG_EOR) ? M_EOR : 0)); if (top != NULL) { ktls_frame(top, tls, &tls_enq_cnt, tls_rtype); } tls_rtype = TLS_RLTYPE_APP; } else #endif top = m_uiotombuf(uio, M_WAITOK, space, (atomic ? max_hdr : 0), (atomic ? M_PKTHDR : 0) | ((flags & MSG_EOR) ? M_EOR : 0)); if (top == NULL) { error = EFAULT; /* only possible error */ goto out; } space -= resid - uio->uio_resid; resid = uio->uio_resid; } if (dontroute) { SOCK_LOCK(so); so->so_options |= SO_DONTROUTE; SOCK_UNLOCK(so); } /* * XXX all the SBS_CANTSENDMORE checks previously * done could be out of date. We could have received * a reset packet in an interrupt or maybe we slept * while doing page faults in uiomove() etc. We * could probably recheck again inside the locking * protection here, but there are probably other * places that this also happens. We must rethink * this. */ VNET_SO_ASSERT(so); pr_send_flag = (flags & MSG_OOB) ? PRUS_OOB : /* * If the user set MSG_EOF, the protocol understands * this flag and nothing left to send then use * PRU_SEND_EOF instead of PRU_SEND. */ ((flags & MSG_EOF) && (so->so_proto->pr_flags & PR_IMPLOPCL) && (resid <= 0)) ? PRUS_EOF : /* If there is more to send set PRUS_MORETOCOME. */ (flags & MSG_MORETOCOME) || (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0; #ifdef KERN_TLS pr_send_flag |= tls_send_flag; #endif error = so->so_proto->pr_send(so, pr_send_flag, top, addr, control, td); if (dontroute) { SOCK_LOCK(so); so->so_options &= ~SO_DONTROUTE; SOCK_UNLOCK(so); } #ifdef KERN_TLS if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) { if (error != 0) { m_freem(top); top = NULL; } else { soref(so); ktls_enqueue(top, so, tls_enq_cnt); } } #endif clen = 0; control = NULL; top = NULL; if (error) goto out; } while (resid && space > 0); } while (resid); out: #ifdef KERN_TLS if (tls != NULL) ktls_free(tls); #endif if (top != NULL) m_freem(top); if (control != NULL) m_freem(control); return (error); } int sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { int error; error = SOCK_IO_SEND_LOCK(so, SBLOCKWAIT(flags)); if (error) return (error); error = sosend_generic_locked(so, addr, uio, top, control, flags, td); SOCK_IO_SEND_UNLOCK(so); return (error); } /* * Send to a socket from a kernel thread. * * XXXGL: in almost all cases uio is NULL and the mbuf is supplied. * Exception is nfs/bootp_subr.c. It is arguable that the VNET context needs * to be set at all. This function should just boil down to a static inline * calling the protocol method. */ int sosend(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_sosend(so, addr, uio, top, control, flags, td); CURVNET_RESTORE(); return (error); } /* * send(2), write(2) or aio_write(2) on a socket. */ int sousrsend(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *control, int flags, struct proc *userproc) { struct thread *td; ssize_t len; int error; td = uio->uio_td; len = uio->uio_resid; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_sosend(so, addr, uio, NULL, control, flags, td); CURVNET_RESTORE(); if (error != 0) { /* * Clear transient errors for stream protocols if they made * some progress. Make exclusion for aio(4) that would * schedule a new write in case of EWOULDBLOCK and clear * error itself. See soaio_process_job(). */ if (uio->uio_resid != len && (so->so_proto->pr_flags & PR_ATOMIC) == 0 && userproc == NULL && (error == ERESTART || error == EINTR || error == EWOULDBLOCK)) error = 0; /* Generation of SIGPIPE can be controlled per socket. */ if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0 && (flags & MSG_NOSIGNAL) == 0) { if (userproc != NULL) { /* aio(4) job */ PROC_LOCK(userproc); kern_psignal(userproc, SIGPIPE); PROC_UNLOCK(userproc); } else { PROC_LOCK(td->td_proc); tdsignal(td, SIGPIPE); PROC_UNLOCK(td->td_proc); } } } return (error); } /* * The part of soreceive() that implements reading non-inline out-of-band * data from a socket. For more complete comments, see soreceive(), from * which this code originated. * * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is * unable to return an mbuf chain to the caller. */ static int soreceive_rcvoob(struct socket *so, struct uio *uio, int flags) { struct protosw *pr = so->so_proto; struct mbuf *m; int error; KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0")); VNET_SO_ASSERT(so); m = m_get(M_WAITOK, MT_DATA); error = pr->pr_rcvoob(so, m, flags & MSG_PEEK); if (error) goto bad; do { error = uiomove(mtod(m, void *), (int) min(uio->uio_resid, m->m_len), uio); m = m_free(m); } while (uio->uio_resid && error == 0 && m); bad: if (m != NULL) m_freem(m); return (error); } /* * Following replacement or removal of the first mbuf on the first mbuf chain * of a socket buffer, push necessary state changes back into the socket * buffer so that other consumers see the values consistently. 'nextrecord' * is the callers locally stored value of the original value of * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes. * NOTE: 'nextrecord' may be NULL. */ static __inline void sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord) { SOCKBUF_LOCK_ASSERT(sb); /* * First, update for the new value of nextrecord. If necessary, make * it the first record. */ if (sb->sb_mb != NULL) sb->sb_mb->m_nextpkt = nextrecord; else sb->sb_mb = nextrecord; /* * Now update any dependent socket buffer fields to reflect the new * state. This is an expanded inline of SB_EMPTY_FIXUP(), with the * addition of a second clause that takes care of the case where * sb_mb has been updated, but remains the last record. */ if (sb->sb_mb == NULL) { sb->sb_mbtail = NULL; sb->sb_lastrecord = NULL; } else if (sb->sb_mb->m_nextpkt == NULL) sb->sb_lastrecord = sb->sb_mb; } /* * Implement receive operations on a socket. We depend on the way that * records are added to the sockbuf by sbappend. In particular, each record * (mbufs linked through m_next) must begin with an address if the protocol * so specifies, followed by an optional mbuf or mbufs containing ancillary * data, and then zero or more mbufs of data. In order to allow parallelism * between network receive and copying to user space, as well as avoid * sleeping with a mutex held, we release the socket buffer mutex during the * user space copy. Although the sockbuf is locked, new data may still be * appended, and thus we must maintain consistency of the sockbuf during that * time. * * The caller may receive the data as a single mbuf chain by supplying an * mbuf **mp0 for use in returning the chain. The uio is then used only for * the count in uio_resid. */ static int soreceive_generic_locked(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp, struct mbuf **controlp, int *flagsp) { struct mbuf *m; int flags, error, offset; ssize_t len; struct protosw *pr = so->so_proto; struct mbuf *nextrecord; int moff, type = 0; ssize_t orig_resid = uio->uio_resid; bool report_real_len = false; SOCK_IO_RECV_ASSERT_LOCKED(so); error = 0; if (flagsp != NULL) { report_real_len = *flagsp & MSG_TRUNC; *flagsp &= ~MSG_TRUNC; flags = *flagsp &~ MSG_EOR; } else flags = 0; restart: SOCKBUF_LOCK(&so->so_rcv); m = so->so_rcv.sb_mb; /* * If we have less data than requested, block awaiting more (subject * to any timeout) if: * 1. the current count is less than the low water mark, or * 2. MSG_DONTWAIT is not set */ if (m == NULL || (((flags & MSG_DONTWAIT) == 0 && sbavail(&so->so_rcv) < uio->uio_resid) && sbavail(&so->so_rcv) < so->so_rcv.sb_lowat && m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) { KASSERT(m != NULL || !sbavail(&so->so_rcv), ("receive: m == %p sbavail == %u", m, sbavail(&so->so_rcv))); if (so->so_error || so->so_rerror) { if (m != NULL) goto dontblock; if (so->so_error) error = so->so_error; else error = so->so_rerror; if ((flags & MSG_PEEK) == 0) { if (so->so_error) so->so_error = 0; else so->so_rerror = 0; } SOCKBUF_UNLOCK(&so->so_rcv); goto release; } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { if (m != NULL) goto dontblock; #ifdef KERN_TLS else if (so->so_rcv.sb_tlsdcc == 0 && so->so_rcv.sb_tlscc == 0) { #else else { #endif SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } for (; m != NULL; m = m->m_next) if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { m = so->so_rcv.sb_mb; goto dontblock; } if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 && (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) { SOCKBUF_UNLOCK(&so->so_rcv); error = ENOTCONN; goto release; } if (uio->uio_resid == 0 && !report_real_len) { SOCKBUF_UNLOCK(&so->so_rcv); goto release; } if ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO))) { SOCKBUF_UNLOCK(&so->so_rcv); error = EWOULDBLOCK; goto release; } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); error = sbwait(so, SO_RCV); SOCKBUF_UNLOCK(&so->so_rcv); if (error) goto release; goto restart; } dontblock: /* * From this point onward, we maintain 'nextrecord' as a cache of the * pointer to the next record in the socket buffer. We must keep the * various socket buffer pointers and local stack versions of the * pointers in sync, pushing out modifications before dropping the * socket buffer mutex, and re-reading them when picking it up. * * Otherwise, we will race with the network stack appending new data * or records onto the socket buffer by using inconsistent/stale * versions of the field, possibly resulting in socket buffer * corruption. * * By holding the high-level sblock(), we prevent simultaneous * readers from pulling off the front of the socket buffer. */ SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb")); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); nextrecord = m->m_nextpkt; if (pr->pr_flags & PR_ADDR) { KASSERT(m->m_type == MT_SONAME, ("m->m_type == %d", m->m_type)); orig_resid = 0; if (psa != NULL) *psa = sodupsockaddr(mtod(m, struct sockaddr *), M_NOWAIT); if (flags & MSG_PEEK) { m = m->m_next; } else { sbfree(&so->so_rcv, m); so->so_rcv.sb_mb = m_free(m); m = so->so_rcv.sb_mb; sockbuf_pushsync(&so->so_rcv, nextrecord); } } /* * Process one or more MT_CONTROL mbufs present before any data mbufs * in the first mbuf chain on the socket buffer. If MSG_PEEK, we * just copy the data; if !MSG_PEEK, we call into the protocol to * perform externalization (or freeing if controlp == NULL). */ if (m != NULL && m->m_type == MT_CONTROL) { struct mbuf *cm = NULL, *cmn; struct mbuf **cme = &cm; #ifdef KERN_TLS struct cmsghdr *cmsg; struct tls_get_record tgr; /* * For MSG_TLSAPPDATA, check for an alert record. * If found, return ENXIO without removing * it from the receive queue. This allows a subsequent * call without MSG_TLSAPPDATA to receive it. * Note that, for TLS, there should only be a single * control mbuf with the TLS_GET_RECORD message in it. */ if (flags & MSG_TLSAPPDATA) { cmsg = mtod(m, struct cmsghdr *); if (cmsg->cmsg_type == TLS_GET_RECORD && cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) { memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr)); if (__predict_false(tgr.tls_type == TLS_RLTYPE_ALERT)) { SOCKBUF_UNLOCK(&so->so_rcv); error = ENXIO; goto release; } } } #endif do { if (flags & MSG_PEEK) { if (controlp != NULL) { *controlp = m_copym(m, 0, m->m_len, M_NOWAIT); controlp = &(*controlp)->m_next; } m = m->m_next; } else { sbfree(&so->so_rcv, m); so->so_rcv.sb_mb = m->m_next; m->m_next = NULL; *cme = m; cme = &(*cme)->m_next; m = so->so_rcv.sb_mb; } } while (m != NULL && m->m_type == MT_CONTROL); if ((flags & MSG_PEEK) == 0) sockbuf_pushsync(&so->so_rcv, nextrecord); while (cm != NULL) { cmn = cm->m_next; cm->m_next = NULL; if (pr->pr_domain->dom_externalize != NULL) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); error = (*pr->pr_domain->dom_externalize) (cm, controlp, flags); SOCKBUF_LOCK(&so->so_rcv); } else if (controlp != NULL) *controlp = cm; else m_freem(cm); if (controlp != NULL) { while (*controlp != NULL) controlp = &(*controlp)->m_next; } cm = cmn; } if (m != NULL) nextrecord = so->so_rcv.sb_mb->m_nextpkt; else nextrecord = so->so_rcv.sb_mb; orig_resid = 0; } if (m != NULL) { if ((flags & MSG_PEEK) == 0) { KASSERT(m->m_nextpkt == nextrecord, ("soreceive: post-control, nextrecord !sync")); if (nextrecord == NULL) { KASSERT(so->so_rcv.sb_mb == m, ("soreceive: post-control, sb_mb!=m")); KASSERT(so->so_rcv.sb_lastrecord == m, ("soreceive: post-control, lastrecord!=m")); } } type = m->m_type; if (type == MT_OOBDATA) flags |= MSG_OOB; } else { if ((flags & MSG_PEEK) == 0) { KASSERT(so->so_rcv.sb_mb == nextrecord, ("soreceive: sb_mb != nextrecord")); if (so->so_rcv.sb_mb == NULL) { KASSERT(so->so_rcv.sb_lastrecord == NULL, ("soreceive: sb_lastercord != NULL")); } } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * Now continue to read any data mbufs off of the head of the socket * buffer until the read request is satisfied. Note that 'type' is * used to store the type of any mbuf reads that have happened so far * such that soreceive() can stop reading if the type changes, which * causes soreceive() to return only one of regular data and inline * out-of-band data in a single socket receive operation. */ moff = 0; offset = 0; while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0 && error == 0) { /* * If the type of mbuf has changed since the last mbuf * examined ('type'), end the receive operation. */ SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) { if (type != m->m_type) break; } else if (type == MT_OOBDATA) break; else KASSERT(m->m_type == MT_DATA, ("m->m_type == %d", m->m_type)); so->so_rcv.sb_state &= ~SBS_RCVATMARK; len = uio->uio_resid; if (so->so_oobmark && len > so->so_oobmark - offset) len = so->so_oobmark - offset; if (len > m->m_len - moff) len = m->m_len - moff; /* * If mp is set, just pass back the mbufs. Otherwise copy * them out via the uio, then free. Sockbuf must be * consistent here (points to current mbuf, it points to next * record) when we drop priority; we must note any additions * to the sockbuf when we block interrupts again. */ if (mp == NULL) { SOCKBUF_LOCK_ASSERT(&so->so_rcv); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); if ((m->m_flags & M_EXTPG) != 0) error = m_unmapped_uiomove(m, moff, uio, (int)len); else error = uiomove(mtod(m, char *) + moff, (int)len, uio); SOCKBUF_LOCK(&so->so_rcv); if (error) { /* * The MT_SONAME mbuf has already been removed * from the record, so it is necessary to * remove the data mbufs, if any, to preserve * the invariant in the case of PR_ADDR that * requires MT_SONAME mbufs at the head of * each record. */ if (pr->pr_flags & PR_ATOMIC && ((flags & MSG_PEEK) == 0)) (void)sbdroprecord_locked(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } else uio->uio_resid -= len; SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (len == m->m_len - moff) { if (m->m_flags & M_EOR) flags |= MSG_EOR; if (flags & MSG_PEEK) { m = m->m_next; moff = 0; } else { nextrecord = m->m_nextpkt; sbfree(&so->so_rcv, m); if (mp != NULL) { m->m_nextpkt = NULL; *mp = m; mp = &m->m_next; so->so_rcv.sb_mb = m = m->m_next; *mp = NULL; } else { so->so_rcv.sb_mb = m_free(m); m = so->so_rcv.sb_mb; } sockbuf_pushsync(&so->so_rcv, nextrecord); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); } } else { if (flags & MSG_PEEK) moff += len; else { if (mp != NULL) { if (flags & MSG_DONTWAIT) { *mp = m_copym(m, 0, len, M_NOWAIT); if (*mp == NULL) { /* * m_copym() couldn't * allocate an mbuf. * Adjust uio_resid back * (it was adjusted * down by len bytes, * which we didn't end * up "copying" over). */ uio->uio_resid += len; break; } } else { SOCKBUF_UNLOCK(&so->so_rcv); *mp = m_copym(m, 0, len, M_WAITOK); SOCKBUF_LOCK(&so->so_rcv); } } sbcut_locked(&so->so_rcv, len); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_oobmark) { if ((flags & MSG_PEEK) == 0) { so->so_oobmark -= len; if (so->so_oobmark == 0) { so->so_rcv.sb_state |= SBS_RCVATMARK; break; } } else { offset += len; if (offset == so->so_oobmark) break; } } if (flags & MSG_EOR) break; /* * If the MSG_WAITALL flag is set (for non-atomic socket), we * must not quit until "uio->uio_resid == 0" or an error * termination. If a signal/timeout occurs, return with a * short count but without error. Keep sockbuf locked * against other readers. */ while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && !sosendallatonce(so) && nextrecord == NULL) { SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_error || so->so_rerror || so->so_rcv.sb_state & SBS_CANTRCVMORE) break; /* * Notify the protocol that some data has been * drained before blocking. */ if (pr->pr_flags & PR_WANTRCVD) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); pr->pr_rcvd(so, flags); SOCKBUF_LOCK(&so->so_rcv); if (__predict_false(so->so_rcv.sb_mb == NULL && (so->so_error || so->so_rerror || so->so_rcv.sb_state & SBS_CANTRCVMORE))) break; } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * We could receive some data while was notifying * the protocol. Skip blocking in this case. */ if (so->so_rcv.sb_mb == NULL) { error = sbwait(so, SO_RCV); if (error) { SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } m = so->so_rcv.sb_mb; if (m != NULL) nextrecord = m->m_nextpkt; } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (m != NULL && pr->pr_flags & PR_ATOMIC) { if (report_real_len) uio->uio_resid -= m_length(m, NULL) - moff; flags |= MSG_TRUNC; if ((flags & MSG_PEEK) == 0) (void) sbdroprecord_locked(&so->so_rcv); } if ((flags & MSG_PEEK) == 0) { if (m == NULL) { /* * First part is an inline SB_EMPTY_FIXUP(). Second * part makes sure sb_lastrecord is up-to-date if * there is still data in the socket buffer. */ so->so_rcv.sb_mb = nextrecord; if (so->so_rcv.sb_mb == NULL) { so->so_rcv.sb_mbtail = NULL; so->so_rcv.sb_lastrecord = NULL; } else if (nextrecord->m_nextpkt == NULL) so->so_rcv.sb_lastrecord = nextrecord; } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * If soreceive() is being done from the socket callback, * then don't need to generate ACK to peer to update window, * since ACK will be generated on return to TCP. */ if (!(flags & MSG_SOCALLBCK) && (pr->pr_flags & PR_WANTRCVD)) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); pr->pr_rcvd(so, flags); SOCKBUF_LOCK(&so->so_rcv); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (orig_resid == uio->uio_resid && orig_resid && (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) { SOCKBUF_UNLOCK(&so->so_rcv); goto restart; } SOCKBUF_UNLOCK(&so->so_rcv); if (flagsp != NULL) *flagsp |= flags; release: return (error); } int soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp, struct mbuf **controlp, int *flagsp) { int error, flags; if (psa != NULL) *psa = NULL; if (controlp != NULL) *controlp = NULL; if (flagsp != NULL) { flags = *flagsp; if ((flags & MSG_OOB) != 0) return (soreceive_rcvoob(so, uio, flags)); } else { flags = 0; } if (mp != NULL) *mp = NULL; error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags)); if (error) return (error); error = soreceive_generic_locked(so, psa, uio, mp, controlp, flagsp); SOCK_IO_RECV_UNLOCK(so); return (error); } /* * Optimized version of soreceive() for stream (TCP) sockets. */ static int soreceive_stream_locked(struct socket *so, struct sockbuf *sb, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int flags) { int len = 0, error = 0, oresid; struct mbuf *m, *n = NULL; SOCK_IO_RECV_ASSERT_LOCKED(so); /* Easy one, no space to copyout anything. */ if (uio->uio_resid == 0) return (EINVAL); oresid = uio->uio_resid; SOCKBUF_LOCK(sb); /* We will never ever get anything unless we are or were connected. */ if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) { error = ENOTCONN; goto out; } restart: SOCKBUF_LOCK_ASSERT(&so->so_rcv); /* Abort if socket has reported problems. */ if (so->so_error) { if (sbavail(sb) > 0) goto deliver; if (oresid > uio->uio_resid) goto out; error = so->so_error; if (!(flags & MSG_PEEK)) so->so_error = 0; goto out; } /* Door is closed. Deliver what is left, if any. */ if (sb->sb_state & SBS_CANTRCVMORE) { if (sbavail(sb) > 0) goto deliver; else goto out; } /* Socket buffer is empty and we shall not block. */ if (sbavail(sb) == 0 && ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) { error = EAGAIN; goto out; } /* Socket buffer got some data that we shall deliver now. */ if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) && ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)) || sbavail(sb) >= sb->sb_lowat || sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat) ) { goto deliver; } /* On MSG_WAITALL we must wait until all data or error arrives. */ if ((flags & MSG_WAITALL) && (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat)) goto deliver; /* * Wait and block until (more) data comes in. * NB: Drops the sockbuf lock during wait. */ error = sbwait(so, SO_RCV); if (error) goto out; goto restart; deliver: SOCKBUF_LOCK_ASSERT(&so->so_rcv); KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__)); KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__)); /* Statistics. */ if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; /* Fill uio until full or current end of socket buffer is reached. */ len = min(uio->uio_resid, sbavail(sb)); if (mp0 != NULL) { /* Dequeue as many mbufs as possible. */ if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) { if (*mp0 == NULL) *mp0 = sb->sb_mb; else m_cat(*mp0, sb->sb_mb); for (m = sb->sb_mb; m != NULL && m->m_len <= len; m = m->m_next) { KASSERT(!(m->m_flags & M_NOTAVAIL), ("%s: m %p not available", __func__, m)); len -= m->m_len; uio->uio_resid -= m->m_len; sbfree(sb, m); n = m; } n->m_next = NULL; sb->sb_mb = m; sb->sb_lastrecord = sb->sb_mb; if (sb->sb_mb == NULL) SB_EMPTY_FIXUP(sb); } /* Copy the remainder. */ if (len > 0) { KASSERT(sb->sb_mb != NULL, ("%s: len > 0 && sb->sb_mb empty", __func__)); m = m_copym(sb->sb_mb, 0, len, M_NOWAIT); if (m == NULL) len = 0; /* Don't flush data from sockbuf. */ else uio->uio_resid -= len; if (*mp0 != NULL) m_cat(*mp0, m); else *mp0 = m; if (*mp0 == NULL) { error = ENOBUFS; goto out; } } } else { /* NB: Must unlock socket buffer as uiomove may sleep. */ SOCKBUF_UNLOCK(sb); error = m_mbuftouio(uio, sb->sb_mb, len); SOCKBUF_LOCK(sb); if (error) goto out; } SBLASTRECORDCHK(sb); SBLASTMBUFCHK(sb); /* * Remove the delivered data from the socket buffer unless we * were only peeking. */ if (!(flags & MSG_PEEK)) { if (len > 0) sbdrop_locked(sb, len); /* Notify protocol that we drained some data. */ if ((so->so_proto->pr_flags & PR_WANTRCVD) && (((flags & MSG_WAITALL) && uio->uio_resid > 0) || !(flags & MSG_SOCALLBCK))) { SOCKBUF_UNLOCK(sb); VNET_SO_ASSERT(so); so->so_proto->pr_rcvd(so, flags); SOCKBUF_LOCK(sb); } } /* * For MSG_WAITALL we may have to loop again and wait for * more data to come in. */ if ((flags & MSG_WAITALL) && uio->uio_resid > 0) goto restart; out: SBLASTRECORDCHK(sb); SBLASTMBUFCHK(sb); SOCKBUF_UNLOCK(sb); return (error); } int soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { struct sockbuf *sb; int error, flags; sb = &so->so_rcv; /* We only do stream sockets. */ if (so->so_type != SOCK_STREAM) return (EINVAL); if (psa != NULL) *psa = NULL; if (flagsp != NULL) flags = *flagsp & ~MSG_EOR; else flags = 0; if (controlp != NULL) *controlp = NULL; if (flags & MSG_OOB) return (soreceive_rcvoob(so, uio, flags)); if (mp0 != NULL) *mp0 = NULL; #ifdef KERN_TLS /* * KTLS store TLS records as records with a control message to * describe the framing. * * We check once here before acquiring locks to optimize the * common case. */ if (sb->sb_tls_info != NULL) return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); #endif /* * Prevent other threads from reading from the socket. This lock may be * dropped in order to sleep waiting for data to arrive. */ error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags)); if (error) return (error); #ifdef KERN_TLS if (__predict_false(sb->sb_tls_info != NULL)) { SOCK_IO_RECV_UNLOCK(so); return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); } #endif error = soreceive_stream_locked(so, sb, psa, uio, mp0, controlp, flags); SOCK_IO_RECV_UNLOCK(so); return (error); } /* * Optimized version of soreceive() for simple datagram cases from userspace. * Unlike in the stream case, we're able to drop a datagram if copyout() * fails, and because we handle datagrams atomically, we don't need to use a * sleep lock to prevent I/O interlacing. */ int soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { struct mbuf *m, *m2; int flags, error; ssize_t len; struct protosw *pr = so->so_proto; struct mbuf *nextrecord; if (psa != NULL) *psa = NULL; if (controlp != NULL) *controlp = NULL; if (flagsp != NULL) flags = *flagsp &~ MSG_EOR; else flags = 0; /* * For any complicated cases, fall back to the full * soreceive_generic(). */ if (mp0 != NULL || (flags & (MSG_PEEK | MSG_OOB | MSG_TRUNC))) return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); /* * Enforce restrictions on use. */ KASSERT((pr->pr_flags & PR_WANTRCVD) == 0, ("soreceive_dgram: wantrcvd")); KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic")); KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0, ("soreceive_dgram: SBS_RCVATMARK")); KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0, ("soreceive_dgram: P_CONNREQUIRED")); /* * Loop blocking while waiting for a datagram. */ SOCKBUF_LOCK(&so->so_rcv); while ((m = so->so_rcv.sb_mb) == NULL) { KASSERT(sbavail(&so->so_rcv) == 0, ("soreceive_dgram: sb_mb NULL but sbavail %u", sbavail(&so->so_rcv))); if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_rcv); return (error); } if (so->so_rcv.sb_state & SBS_CANTRCVMORE || uio->uio_resid == 0) { SOCKBUF_UNLOCK(&so->so_rcv); return (0); } if ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO))) { SOCKBUF_UNLOCK(&so->so_rcv); return (EWOULDBLOCK); } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); error = sbwait(so, SO_RCV); if (error) { SOCKBUF_UNLOCK(&so->so_rcv); return (error); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); nextrecord = m->m_nextpkt; if (nextrecord == NULL) { KASSERT(so->so_rcv.sb_lastrecord == m, ("soreceive_dgram: lastrecord != m")); } KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord, ("soreceive_dgram: m_nextpkt != nextrecord")); /* * Pull 'm' and its chain off the front of the packet queue. */ so->so_rcv.sb_mb = NULL; sockbuf_pushsync(&so->so_rcv, nextrecord); /* * Walk 'm's chain and free that many bytes from the socket buffer. */ for (m2 = m; m2 != NULL; m2 = m2->m_next) sbfree(&so->so_rcv, m2); /* * Do a few last checks before we let go of the lock. */ SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); if (pr->pr_flags & PR_ADDR) { KASSERT(m->m_type == MT_SONAME, ("m->m_type == %d", m->m_type)); if (psa != NULL) *psa = sodupsockaddr(mtod(m, struct sockaddr *), M_WAITOK); m = m_free(m); } KASSERT(m, ("%s: no data or control after soname", __func__)); /* * Packet to copyout() is now in 'm' and it is disconnected from the * queue. * * Process one or more MT_CONTROL mbufs present before any data mbufs * in the first mbuf chain on the socket buffer. We call into the * protocol to perform externalization (or freeing if controlp == * NULL). In some cases there can be only MT_CONTROL mbufs without * MT_DATA mbufs. */ if (m->m_type == MT_CONTROL) { struct mbuf *cm = NULL, *cmn; struct mbuf **cme = &cm; do { m2 = m->m_next; m->m_next = NULL; *cme = m; cme = &(*cme)->m_next; m = m2; } while (m != NULL && m->m_type == MT_CONTROL); while (cm != NULL) { cmn = cm->m_next; cm->m_next = NULL; if (pr->pr_domain->dom_externalize != NULL) { error = (*pr->pr_domain->dom_externalize) (cm, controlp, flags); } else if (controlp != NULL) *controlp = cm; else m_freem(cm); if (controlp != NULL) { while (*controlp != NULL) controlp = &(*controlp)->m_next; } cm = cmn; } } KASSERT(m == NULL || m->m_type == MT_DATA, ("soreceive_dgram: !data")); while (m != NULL && uio->uio_resid > 0) { len = uio->uio_resid; if (len > m->m_len) len = m->m_len; error = uiomove(mtod(m, char *), (int)len, uio); if (error) { m_freem(m); return (error); } if (len == m->m_len) m = m_free(m); else { m->m_data += len; m->m_len -= len; } } if (m != NULL) { flags |= MSG_TRUNC; m_freem(m); } if (flagsp != NULL) *flagsp |= flags; return (0); } int soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_soreceive(so, psa, uio, mp0, controlp, flagsp); CURVNET_RESTORE(); return (error); } int soshutdown(struct socket *so, enum shutdown_how how) { int error; CURVNET_SET(so->so_vnet); error = so->so_proto->pr_shutdown(so, how); CURVNET_RESTORE(); return (error); } /* * Used by several pr_shutdown implementations that use generic socket buffers. */ void sorflush(struct socket *so) { int error; VNET_SO_ASSERT(so); /* * Dislodge threads currently blocked in receive and wait to acquire * a lock against other simultaneous readers before clearing the * socket buffer. Don't let our acquire be interrupted by a signal * despite any existing socket disposition on interruptable waiting. * * The SOCK_IO_RECV_LOCK() is important here as there some pr_soreceive * methods that read the top of the socket buffer without acquisition * of the socket buffer mutex, assuming that top of the buffer * exclusively belongs to the read(2) syscall. This is handy when * performing MSG_PEEK. */ socantrcvmore(so); error = SOCK_IO_RECV_LOCK(so, SBL_WAIT | SBL_NOINTR); if (error != 0) { KASSERT(SOLISTENING(so), ("%s: soiolock(%p) failed", __func__, so)); return; } sbrelease(so, SO_RCV); SOCK_IO_RECV_UNLOCK(so); } #ifdef SOCKET_HHOOK /* * Wrapper for Socket established helper hook. * Parameters: socket, context of the hook point, hook id. */ static inline int hhook_run_socket(struct socket *so, void *hctx, int32_t h_id) { struct socket_hhook_data hhook_data = { .so = so, .hctx = hctx, .m = NULL, .status = 0 }; CURVNET_SET(so->so_vnet); HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd); CURVNET_RESTORE(); /* Ugly but needed, since hhooks return void for now */ return (hhook_data.status); } #endif /* * Perhaps this routine, and sooptcopyout(), below, ought to come in an * additional variant to handle the case where the option value needs to be * some kind of integer, but not a specific size. In addition to their use * here, these functions are also called by the protocol-level pr_ctloutput() * routines. */ int sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen) { size_t valsize; /* * If the user gives us more than we wanted, we ignore it, but if we * don't get the minimum length the caller wants, we return EINVAL. * On success, sopt->sopt_valsize is set to however much we actually * retrieved. */ if ((valsize = sopt->sopt_valsize) < minlen) return EINVAL; if (valsize > len) sopt->sopt_valsize = valsize = len; if (sopt->sopt_td != NULL) return (copyin(sopt->sopt_val, buf, valsize)); bcopy(sopt->sopt_val, buf, valsize); return (0); } /* * Kernel version of setsockopt(2). * * XXX: optlen is size_t, not socklen_t */ int so_setsockopt(struct socket *so, int level, int optname, void *optval, size_t optlen) { struct sockopt sopt; sopt.sopt_level = level; sopt.sopt_name = optname; sopt.sopt_dir = SOPT_SET; sopt.sopt_val = optval; sopt.sopt_valsize = optlen; sopt.sopt_td = NULL; return (sosetopt(so, &sopt)); } int sosetopt(struct socket *so, struct sockopt *sopt) { int error, optval; struct linger l; struct timeval tv; sbintime_t val, *valp; uint32_t val32; #ifdef MAC struct mac extmac; #endif CURVNET_SET(so->so_vnet); error = 0; if (sopt->sopt_level != SOL_SOCKET) { if (so->so_proto->pr_ctloutput != NULL) error = (*so->so_proto->pr_ctloutput)(so, sopt); else error = ENOPROTOOPT; } else { switch (sopt->sopt_name) { case SO_ACCEPTFILTER: error = accept_filt_setopt(so, sopt); if (error) goto bad; break; case SO_LINGER: error = sooptcopyin(sopt, &l, sizeof l, sizeof l); if (error) goto bad; if (l.l_linger < 0 || l.l_linger > USHRT_MAX || l.l_linger > (INT_MAX / hz)) { error = EDOM; goto bad; } SOCK_LOCK(so); so->so_linger = l.l_linger; if (l.l_onoff) so->so_options |= SO_LINGER; else so->so_options &= ~SO_LINGER; SOCK_UNLOCK(so); break; case SO_DEBUG: case SO_KEEPALIVE: case SO_DONTROUTE: case SO_USELOOPBACK: case SO_BROADCAST: case SO_REUSEADDR: case SO_REUSEPORT: case SO_REUSEPORT_LB: case SO_OOBINLINE: case SO_TIMESTAMP: case SO_BINTIME: case SO_NOSIGPIPE: case SO_NO_DDP: case SO_NO_OFFLOAD: case SO_RERROR: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; SOCK_LOCK(so); if (optval) so->so_options |= sopt->sopt_name; else so->so_options &= ~sopt->sopt_name; SOCK_UNLOCK(so); break; case SO_SETFIB: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; if (optval < 0 || optval >= rt_numfibs) { error = EINVAL; goto bad; } if (((so->so_proto->pr_domain->dom_family == PF_INET) || (so->so_proto->pr_domain->dom_family == PF_INET6) || (so->so_proto->pr_domain->dom_family == PF_ROUTE))) so->so_fibnum = optval; else so->so_fibnum = 0; break; case SO_USER_COOKIE: error = sooptcopyin(sopt, &val32, sizeof val32, sizeof val32); if (error) goto bad; so->so_user_cookie = val32; break; case SO_SNDBUF: case SO_RCVBUF: case SO_SNDLOWAT: case SO_RCVLOWAT: error = so->so_proto->pr_setsbopt(so, sopt); if (error) goto bad; break; case SO_SNDTIMEO: case SO_RCVTIMEO: #ifdef COMPAT_FREEBSD32 if (SV_CURPROC_FLAG(SV_ILP32)) { struct timeval32 tv32; error = sooptcopyin(sopt, &tv32, sizeof tv32, sizeof tv32); CP(tv32, tv, tv_sec); CP(tv32, tv, tv_usec); } else #endif error = sooptcopyin(sopt, &tv, sizeof tv, sizeof tv); if (error) goto bad; if (tv.tv_sec < 0 || tv.tv_usec < 0 || tv.tv_usec >= 1000000) { error = EDOM; goto bad; } if (tv.tv_sec > INT32_MAX) val = SBT_MAX; else val = tvtosbt(tv); SOCK_LOCK(so); valp = sopt->sopt_name == SO_SNDTIMEO ? (SOLISTENING(so) ? &so->sol_sbsnd_timeo : &so->so_snd.sb_timeo) : (SOLISTENING(so) ? &so->sol_sbrcv_timeo : &so->so_rcv.sb_timeo); *valp = val; SOCK_UNLOCK(so); break; case SO_LABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof extmac, sizeof extmac); if (error) goto bad; error = mac_setsockopt_label(sopt->sopt_td->td_ucred, so, &extmac); #else error = EOPNOTSUPP; #endif break; case SO_TS_CLOCK: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; if (optval < 0 || optval > SO_TS_CLOCK_MAX) { error = EINVAL; goto bad; } so->so_ts_clock = optval; break; case SO_MAX_PACING_RATE: error = sooptcopyin(sopt, &val32, sizeof(val32), sizeof(val32)); if (error) goto bad; so->so_max_pacing_rate = val32; break; case SO_SPLICE: { struct splice splice; #ifdef COMPAT_FREEBSD32 if (SV_CURPROC_FLAG(SV_ILP32)) { struct splice32 splice32; error = sooptcopyin(sopt, &splice32, sizeof(splice32), sizeof(splice32)); if (error == 0) { splice.sp_fd = splice32.sp_fd; splice.sp_max = splice32.sp_max; CP(splice32.sp_idle, splice.sp_idle, tv_sec); CP(splice32.sp_idle, splice.sp_idle, tv_usec); } } else #endif { error = sooptcopyin(sopt, &splice, sizeof(splice), sizeof(splice)); } if (error) goto bad; #ifdef KTRACE if (KTRPOINT(curthread, KTR_STRUCT)) ktrsplice(&splice); #endif error = splice_init(); if (error != 0) goto bad; if (splice.sp_fd >= 0) { struct file *fp; struct socket *so2; if (!cap_rights_contains(sopt->sopt_rights, &cap_recv_rights)) { error = ENOTCAPABLE; goto bad; } error = getsock(sopt->sopt_td, splice.sp_fd, &cap_send_rights, &fp); if (error != 0) goto bad; so2 = fp->f_data; error = so_splice(so, so2, &splice); fdrop(fp, sopt->sopt_td); } else { error = so_unsplice(so, false); } break; } default: #ifdef SOCKET_HHOOK if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) error = hhook_run_socket(so, sopt, HHOOK_SOCKET_OPT); else #endif error = ENOPROTOOPT; break; } if (error == 0 && so->so_proto->pr_ctloutput != NULL) (void)(*so->so_proto->pr_ctloutput)(so, sopt); } bad: CURVNET_RESTORE(); return (error); } /* * Helper routine for getsockopt. */ int sooptcopyout(struct sockopt *sopt, const void *buf, size_t len) { int error; size_t valsize; error = 0; /* * Documented get behavior is that we always return a value, possibly * truncated to fit in the user's buffer. Traditional behavior is * that we always tell the user precisely how much we copied, rather * than something useful like the total amount we had available for * her. Note that this interface is not idempotent; the entire * answer must be generated ahead of time. */ valsize = min(len, sopt->sopt_valsize); sopt->sopt_valsize = valsize; if (sopt->sopt_val != NULL) { if (sopt->sopt_td != NULL) error = copyout(buf, sopt->sopt_val, valsize); else bcopy(buf, sopt->sopt_val, valsize); } return (error); } int sogetopt(struct socket *so, struct sockopt *sopt) { int error, optval; struct linger l; struct timeval tv; #ifdef MAC struct mac extmac; #endif CURVNET_SET(so->so_vnet); error = 0; if (sopt->sopt_level != SOL_SOCKET) { if (so->so_proto->pr_ctloutput != NULL) error = (*so->so_proto->pr_ctloutput)(so, sopt); else error = ENOPROTOOPT; CURVNET_RESTORE(); return (error); } else { switch (sopt->sopt_name) { case SO_ACCEPTFILTER: error = accept_filt_getopt(so, sopt); break; case SO_LINGER: SOCK_LOCK(so); l.l_onoff = so->so_options & SO_LINGER; l.l_linger = so->so_linger; SOCK_UNLOCK(so); error = sooptcopyout(sopt, &l, sizeof l); break; case SO_USELOOPBACK: case SO_DONTROUTE: case SO_DEBUG: case SO_KEEPALIVE: case SO_REUSEADDR: case SO_REUSEPORT: case SO_REUSEPORT_LB: case SO_BROADCAST: case SO_OOBINLINE: case SO_ACCEPTCONN: case SO_TIMESTAMP: case SO_BINTIME: case SO_NOSIGPIPE: case SO_NO_DDP: case SO_NO_OFFLOAD: case SO_RERROR: optval = so->so_options & sopt->sopt_name; integer: error = sooptcopyout(sopt, &optval, sizeof optval); break; case SO_DOMAIN: optval = so->so_proto->pr_domain->dom_family; goto integer; case SO_TYPE: optval = so->so_type; goto integer; case SO_PROTOCOL: optval = so->so_proto->pr_protocol; goto integer; case SO_ERROR: SOCK_LOCK(so); if (so->so_error) { optval = so->so_error; so->so_error = 0; } else { optval = so->so_rerror; so->so_rerror = 0; } SOCK_UNLOCK(so); goto integer; case SO_SNDBUF: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat : so->so_snd.sb_hiwat; SOCK_UNLOCK(so); goto integer; case SO_RCVBUF: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat : so->so_rcv.sb_hiwat; SOCK_UNLOCK(so); goto integer; case SO_SNDLOWAT: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_sbsnd_lowat : so->so_snd.sb_lowat; SOCK_UNLOCK(so); goto integer; case SO_RCVLOWAT: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_sbrcv_lowat : so->so_rcv.sb_lowat; SOCK_UNLOCK(so); goto integer; case SO_SNDTIMEO: case SO_RCVTIMEO: SOCK_LOCK(so); tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ? (SOLISTENING(so) ? so->sol_sbsnd_timeo : so->so_snd.sb_timeo) : (SOLISTENING(so) ? so->sol_sbrcv_timeo : so->so_rcv.sb_timeo)); SOCK_UNLOCK(so); #ifdef COMPAT_FREEBSD32 if (SV_CURPROC_FLAG(SV_ILP32)) { struct timeval32 tv32; CP(tv, tv32, tv_sec); CP(tv, tv32, tv_usec); error = sooptcopyout(sopt, &tv32, sizeof tv32); } else #endif error = sooptcopyout(sopt, &tv, sizeof tv); break; case SO_LABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof(extmac), sizeof(extmac)); if (error) goto bad; error = mac_getsockopt_label(sopt->sopt_td->td_ucred, so, &extmac); if (error) goto bad; /* Don't copy out extmac, it is unchanged. */ #else error = EOPNOTSUPP; #endif break; case SO_PEERLABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof(extmac), sizeof(extmac)); if (error) goto bad; error = mac_getsockopt_peerlabel( sopt->sopt_td->td_ucred, so, &extmac); if (error) goto bad; /* Don't copy out extmac, it is unchanged. */ #else error = EOPNOTSUPP; #endif break; case SO_LISTENQLIMIT: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_qlimit : 0; SOCK_UNLOCK(so); goto integer; case SO_LISTENQLEN: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_qlen : 0; SOCK_UNLOCK(so); goto integer; case SO_LISTENINCQLEN: SOCK_LOCK(so); optval = SOLISTENING(so) ? so->sol_incqlen : 0; SOCK_UNLOCK(so); goto integer; case SO_TS_CLOCK: optval = so->so_ts_clock; goto integer; case SO_MAX_PACING_RATE: optval = so->so_max_pacing_rate; goto integer; case SO_SPLICE: { off_t n; /* * Acquire the I/O lock to serialize with * so_splice_xfer(). This is not required for * correctness, but makes testing simpler: once a byte * has been transmitted to the sink and observed (e.g., * by reading from the socket to which the sink is * connected), a subsequent getsockopt(SO_SPLICE) will * return an up-to-date value. */ error = SOCK_IO_RECV_LOCK(so, SBL_WAIT); if (error != 0) goto bad; SOCK_LOCK(so); if (SOLISTENING(so)) { n = 0; } else { n = so->so_splice_sent; } SOCK_UNLOCK(so); SOCK_IO_RECV_UNLOCK(so); error = sooptcopyout(sopt, &n, sizeof(n)); break; } default: #ifdef SOCKET_HHOOK if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) error = hhook_run_socket(so, sopt, HHOOK_SOCKET_OPT); else #endif error = ENOPROTOOPT; break; } } bad: CURVNET_RESTORE(); return (error); } int soopt_getm(struct sockopt *sopt, struct mbuf **mp) { struct mbuf *m, *m_prev; int sopt_size = sopt->sopt_valsize; MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); if (m == NULL) return ENOBUFS; if (sopt_size > MLEN) { MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); return ENOBUFS; } m->m_len = min(MCLBYTES, sopt_size); } else { m->m_len = min(MLEN, sopt_size); } sopt_size -= m->m_len; *mp = m; m_prev = m; while (sopt_size) { MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); if (m == NULL) { m_freem(*mp); return ENOBUFS; } if (sopt_size > MLEN) { MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK : M_NOWAIT); if ((m->m_flags & M_EXT) == 0) { m_freem(m); m_freem(*mp); return ENOBUFS; } m->m_len = min(MCLBYTES, sopt_size); } else { m->m_len = min(MLEN, sopt_size); } sopt_size -= m->m_len; m_prev->m_next = m; m_prev = m; } return (0); } int soopt_mcopyin(struct sockopt *sopt, struct mbuf *m) { struct mbuf *m0 = m; if (sopt->sopt_val == NULL) return (0); while (m != NULL && sopt->sopt_valsize >= m->m_len) { if (sopt->sopt_td != NULL) { int error; error = copyin(sopt->sopt_val, mtod(m, char *), m->m_len); if (error != 0) { m_freem(m0); return(error); } } else bcopy(sopt->sopt_val, mtod(m, char *), m->m_len); sopt->sopt_valsize -= m->m_len; sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; m = m->m_next; } if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */ panic("ip6_sooptmcopyin"); return (0); } int soopt_mcopyout(struct sockopt *sopt, struct mbuf *m) { struct mbuf *m0 = m; size_t valsize = 0; if (sopt->sopt_val == NULL) return (0); while (m != NULL && sopt->sopt_valsize >= m->m_len) { if (sopt->sopt_td != NULL) { int error; error = copyout(mtod(m, char *), sopt->sopt_val, m->m_len); if (error != 0) { m_freem(m0); return(error); } } else bcopy(mtod(m, char *), sopt->sopt_val, m->m_len); sopt->sopt_valsize -= m->m_len; sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; valsize += m->m_len; m = m->m_next; } if (m != NULL) { /* enough soopt buffer should be given from user-land */ m_freem(m0); return(EINVAL); } sopt->sopt_valsize = valsize; return (0); } /* * sohasoutofband(): protocol notifies socket layer of the arrival of new * out-of-band data, which will then notify socket consumers. */ void sohasoutofband(struct socket *so) { if (so->so_sigio != NULL) pgsigio(&so->so_sigio, SIGURG, 0); selwakeuppri(&so->so_rdsel, PSOCK); } int sopoll(struct socket *so, int events, struct ucred *active_cred, struct thread *td) { /* * We do not need to set or assert curvnet as long as everyone uses * sopoll_generic(). */ return (so->so_proto->pr_sopoll(so, events, active_cred, td)); } int sopoll_generic(struct socket *so, int events, struct ucred *active_cred, struct thread *td) { int revents; SOCK_LOCK(so); if (SOLISTENING(so)) { if (!(events & (POLLIN | POLLRDNORM))) revents = 0; else if (!TAILQ_EMPTY(&so->sol_comp)) revents = events & (POLLIN | POLLRDNORM); else if ((events & POLLINIGNEOF) == 0 && so->so_error) revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP; else { selrecord(td, &so->so_rdsel); revents = 0; } } else { revents = 0; SOCK_SENDBUF_LOCK(so); SOCK_RECVBUF_LOCK(so); if (events & (POLLIN | POLLRDNORM)) if (soreadabledata(so) && !isspliced(so)) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (sowriteable(so) && !issplicedback(so)) revents |= events & (POLLOUT | POLLWRNORM); if (events & (POLLPRI | POLLRDBAND)) if (so->so_oobmark || (so->so_rcv.sb_state & SBS_RCVATMARK)) revents |= events & (POLLPRI | POLLRDBAND); if ((events & POLLINIGNEOF) == 0) { if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { revents |= events & (POLLIN | POLLRDNORM); if (so->so_snd.sb_state & SBS_CANTSENDMORE) revents |= POLLHUP; } } if (so->so_rcv.sb_state & SBS_CANTRCVMORE) revents |= events & POLLRDHUP; if (revents == 0) { if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) { selrecord(td, &so->so_rdsel); so->so_rcv.sb_flags |= SB_SEL; } if (events & (POLLOUT | POLLWRNORM)) { selrecord(td, &so->so_wrsel); so->so_snd.sb_flags |= SB_SEL; } } SOCK_RECVBUF_UNLOCK(so); SOCK_SENDBUF_UNLOCK(so); } SOCK_UNLOCK(so); return (revents); } int soo_kqfilter(struct file *fp, struct knote *kn) { struct socket *so = kn->kn_fp->f_data; struct sockbuf *sb; sb_which which; struct knlist *knl; switch (kn->kn_filter) { case EVFILT_READ: kn->kn_fop = &soread_filtops; knl = &so->so_rdsel.si_note; sb = &so->so_rcv; which = SO_RCV; break; case EVFILT_WRITE: kn->kn_fop = &sowrite_filtops; knl = &so->so_wrsel.si_note; sb = &so->so_snd; which = SO_SND; break; case EVFILT_EMPTY: kn->kn_fop = &soempty_filtops; knl = &so->so_wrsel.si_note; sb = &so->so_snd; which = SO_SND; break; default: return (EINVAL); } SOCK_LOCK(so); if (SOLISTENING(so)) { knlist_add(knl, kn, 1); } else { SOCK_BUF_LOCK(so, which); knlist_add(knl, kn, 1); sb->sb_flags |= SB_KNOTE; SOCK_BUF_UNLOCK(so, which); } SOCK_UNLOCK(so); return (0); } static void filt_sordetach(struct knote *kn) { struct socket *so = kn->kn_fp->f_data; so_rdknl_lock(so); knlist_remove(&so->so_rdsel.si_note, kn, 1); if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note)) so->so_rcv.sb_flags &= ~SB_KNOTE; so_rdknl_unlock(so); } /*ARGSUSED*/ static int filt_soread(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) { SOCK_LOCK_ASSERT(so); kn->kn_data = so->sol_qlen; if (so->so_error) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } return (!TAILQ_EMPTY(&so->sol_comp)); } if ((so->so_rcv.sb_flags & SB_SPLICED) != 0) return (0); SOCK_RECVBUF_LOCK_ASSERT(so); kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl; if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } else if (so->so_error || so->so_rerror) return (1); if (kn->kn_sfflags & NOTE_LOWAT) { if (kn->kn_data >= kn->kn_sdata) return (1); } else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat) return (1); #ifdef SOCKET_HHOOK /* This hook returning non-zero indicates an event, not error */ return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD)); #else return (0); #endif } static void filt_sowdetach(struct knote *kn) { struct socket *so = kn->kn_fp->f_data; so_wrknl_lock(so); knlist_remove(&so->so_wrsel.si_note, kn, 1); if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note)) so->so_snd.sb_flags &= ~SB_KNOTE; so_wrknl_unlock(so); } /*ARGSUSED*/ static int filt_sowrite(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) return (0); SOCK_SENDBUF_LOCK_ASSERT(so); kn->kn_data = sbspace(&so->so_snd); #ifdef SOCKET_HHOOK hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE); #endif if (so->so_snd.sb_state & SBS_CANTSENDMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } else if (so->so_error) /* temporary udp error */ return (1); else if (((so->so_state & SS_ISCONNECTED) == 0) && (so->so_proto->pr_flags & PR_CONNREQUIRED)) return (0); else if (kn->kn_sfflags & NOTE_LOWAT) return (kn->kn_data >= kn->kn_sdata); else return (kn->kn_data >= so->so_snd.sb_lowat); } static int filt_soempty(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) return (1); SOCK_SENDBUF_LOCK_ASSERT(so); kn->kn_data = sbused(&so->so_snd); if (kn->kn_data == 0) return (1); else return (0); } int socheckuid(struct socket *so, uid_t uid) { if (so == NULL) return (EPERM); if (so->so_cred->cr_uid != uid) return (EPERM); return (0); } /* * These functions are used by protocols to notify the socket layer (and its * consumers) of state changes in the sockets driven by protocol-side events. */ /* * Procedures to manipulate state flags of socket and do appropriate wakeups. * * Normal sequence from the active (originating) side is that * soisconnecting() is called during processing of connect() call, resulting * in an eventual call to soisconnected() if/when the connection is * established. When the connection is torn down soisdisconnecting() is * called during processing of disconnect() call, and soisdisconnected() is * called when the connection to the peer is totally severed. The semantics * of these routines are such that connectionless protocols can call * soisconnected() and soisdisconnected() only, bypassing the in-progress * calls when setting up a ``connection'' takes no time. * * From the passive side, a socket is created with two queues of sockets: * so_incomp for connections in progress and so_comp for connections already * made and awaiting user acceptance. As a protocol is preparing incoming * connections, it creates a socket structure queued on so_incomp by calling * sonewconn(). When the connection is established, soisconnected() is * called, and transfers the socket structure to so_comp, making it available * to accept(). * * If a socket is closed with sockets on either so_incomp or so_comp, these * sockets are dropped. * * If higher-level protocols are implemented in the kernel, the wakeups done * here will sometimes cause software-interrupt process scheduling. */ void soisconnecting(struct socket *so) { SOCK_LOCK(so); so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); so->so_state |= SS_ISCONNECTING; SOCK_UNLOCK(so); } void soisconnected(struct socket *so) { bool last __diagused; SOCK_LOCK(so); so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING); so->so_state |= SS_ISCONNECTED; if (so->so_qstate == SQ_INCOMP) { struct socket *head = so->so_listen; int ret; KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so)); /* * Promoting a socket from incomplete queue to complete, we * need to go through reverse order of locking. We first do * trylock, and if that doesn't succeed, we go the hard way * leaving a reference and rechecking consistency after proper * locking. */ if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) { soref(head); SOCK_UNLOCK(so); SOLISTEN_LOCK(head); SOCK_LOCK(so); if (__predict_false(head != so->so_listen)) { /* * The socket went off the listen queue, * should be lost race to close(2) of sol. * The socket is about to soabort(). */ SOCK_UNLOCK(so); sorele_locked(head); return; } last = refcount_release(&head->so_count); KASSERT(!last, ("%s: released last reference for %p", __func__, head)); } again: if ((so->so_options & SO_ACCEPTFILTER) == 0) { TAILQ_REMOVE(&head->sol_incomp, so, so_list); head->sol_incqlen--; TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); head->sol_qlen++; so->so_qstate = SQ_COMP; SOCK_UNLOCK(so); solisten_wakeup(head); /* unlocks */ } else { SOCK_RECVBUF_LOCK(so); soupcall_set(so, SO_RCV, head->sol_accept_filter->accf_callback, head->sol_accept_filter_arg); so->so_options &= ~SO_ACCEPTFILTER; ret = head->sol_accept_filter->accf_callback(so, head->sol_accept_filter_arg, M_NOWAIT); if (ret == SU_ISCONNECTED) { soupcall_clear(so, SO_RCV); SOCK_RECVBUF_UNLOCK(so); goto again; } SOCK_RECVBUF_UNLOCK(so); SOCK_UNLOCK(so); SOLISTEN_UNLOCK(head); } return; } SOCK_UNLOCK(so); wakeup(&so->so_timeo); sorwakeup(so); sowwakeup(so); } void soisdisconnecting(struct socket *so) { SOCK_LOCK(so); so->so_state &= ~SS_ISCONNECTING; so->so_state |= SS_ISDISCONNECTING; if (!SOLISTENING(so)) { SOCK_RECVBUF_LOCK(so); socantrcvmore_locked(so); SOCK_SENDBUF_LOCK(so); socantsendmore_locked(so); } SOCK_UNLOCK(so); wakeup(&so->so_timeo); } void soisdisconnected(struct socket *so) { SOCK_LOCK(so); /* * There is at least one reader of so_state that does not * acquire socket lock, namely soreceive_generic(). Ensure * that it never sees all flags that track connection status * cleared, by ordering the update with a barrier semantic of * our release thread fence. */ so->so_state |= SS_ISDISCONNECTED; atomic_thread_fence_rel(); so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); if (!SOLISTENING(so)) { SOCK_UNLOCK(so); SOCK_RECVBUF_LOCK(so); socantrcvmore_locked(so); SOCK_SENDBUF_LOCK(so); sbdrop_locked(&so->so_snd, sbused(&so->so_snd)); socantsendmore_locked(so); } else SOCK_UNLOCK(so); wakeup(&so->so_timeo); } int soiolock(struct socket *so, struct sx *sx, int flags) { int error; KASSERT((flags & SBL_VALID) == flags, ("soiolock: invalid flags %#x", flags)); if ((flags & SBL_WAIT) != 0) { if ((flags & SBL_NOINTR) != 0) { sx_xlock(sx); } else { error = sx_xlock_sig(sx); if (error != 0) return (error); } } else if (!sx_try_xlock(sx)) { return (EWOULDBLOCK); } if (__predict_false(SOLISTENING(so))) { sx_xunlock(sx); return (ENOTCONN); } return (0); } void soiounlock(struct sx *sx) { sx_xunlock(sx); } /* * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. */ struct sockaddr * sodupsockaddr(const struct sockaddr *sa, int mflags) { struct sockaddr *sa2; sa2 = malloc(sa->sa_len, M_SONAME, mflags); if (sa2) bcopy(sa, sa2, sa->sa_len); return sa2; } /* * Register per-socket destructor. */ void sodtor_set(struct socket *so, so_dtor_t *func) { SOCK_LOCK_ASSERT(so); so->so_dtor = func; } /* * Register per-socket buffer upcalls. */ void soupcall_set(struct socket *so, sb_which which, so_upcall_t func, void *arg) { struct sockbuf *sb; KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); switch (which) { case SO_RCV: sb = &so->so_rcv; break; case SO_SND: sb = &so->so_snd; break; } SOCK_BUF_LOCK_ASSERT(so, which); sb->sb_upcall = func; sb->sb_upcallarg = arg; sb->sb_flags |= SB_UPCALL; } void soupcall_clear(struct socket *so, sb_which which) { struct sockbuf *sb; KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); switch (which) { case SO_RCV: sb = &so->so_rcv; break; case SO_SND: sb = &so->so_snd; break; } SOCK_BUF_LOCK_ASSERT(so, which); KASSERT(sb->sb_upcall != NULL, ("%s: so %p no upcall to clear", __func__, so)); sb->sb_upcall = NULL; sb->sb_upcallarg = NULL; sb->sb_flags &= ~SB_UPCALL; } void solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg) { SOLISTEN_LOCK_ASSERT(so); so->sol_upcall = func; so->sol_upcallarg = arg; } static void so_rdknl_lock(void *arg) { struct socket *so = arg; retry: if (SOLISTENING(so)) { SOLISTEN_LOCK(so); } else { SOCK_RECVBUF_LOCK(so); if (__predict_false(SOLISTENING(so))) { SOCK_RECVBUF_UNLOCK(so); goto retry; } } } static void so_rdknl_unlock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOLISTEN_UNLOCK(so); else SOCK_RECVBUF_UNLOCK(so); } static void so_rdknl_assert_lock(void *arg, int what) { struct socket *so = arg; if (what == LA_LOCKED) { if (SOLISTENING(so)) SOLISTEN_LOCK_ASSERT(so); else SOCK_RECVBUF_LOCK_ASSERT(so); } else { if (SOLISTENING(so)) SOLISTEN_UNLOCK_ASSERT(so); else SOCK_RECVBUF_UNLOCK_ASSERT(so); } } static void so_wrknl_lock(void *arg) { struct socket *so = arg; retry: if (SOLISTENING(so)) { SOLISTEN_LOCK(so); } else { SOCK_SENDBUF_LOCK(so); if (__predict_false(SOLISTENING(so))) { SOCK_SENDBUF_UNLOCK(so); goto retry; } } } static void so_wrknl_unlock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOLISTEN_UNLOCK(so); else SOCK_SENDBUF_UNLOCK(so); } static void so_wrknl_assert_lock(void *arg, int what) { struct socket *so = arg; if (what == LA_LOCKED) { if (SOLISTENING(so)) SOLISTEN_LOCK_ASSERT(so); else SOCK_SENDBUF_LOCK_ASSERT(so); } else { if (SOLISTENING(so)) SOLISTEN_UNLOCK_ASSERT(so); else SOCK_SENDBUF_UNLOCK_ASSERT(so); } } /* * Create an external-format (``xsocket'') structure using the information in * the kernel-format socket structure pointed to by so. This is done to * reduce the spew of irrelevant information over this interface, to isolate * user code from changes in the kernel structure, and potentially to provide * information-hiding if we decide that some of this information should be * hidden from users. */ void sotoxsocket(struct socket *so, struct xsocket *xso) { bzero(xso, sizeof(*xso)); xso->xso_len = sizeof *xso; xso->xso_so = (uintptr_t)so; xso->so_type = so->so_type; xso->so_options = so->so_options; xso->so_linger = so->so_linger; xso->so_state = so->so_state; xso->so_pcb = (uintptr_t)so->so_pcb; xso->xso_protocol = so->so_proto->pr_protocol; xso->xso_family = so->so_proto->pr_domain->dom_family; xso->so_timeo = so->so_timeo; xso->so_error = so->so_error; xso->so_uid = so->so_cred->cr_uid; xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; SOCK_LOCK(so); xso->so_fibnum = so->so_fibnum; if (SOLISTENING(so)) { xso->so_qlen = so->sol_qlen; xso->so_incqlen = so->sol_incqlen; xso->so_qlimit = so->sol_qlimit; xso->so_oobmark = 0; } else { xso->so_state |= so->so_qstate; xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0; xso->so_oobmark = so->so_oobmark; sbtoxsockbuf(&so->so_snd, &xso->so_snd); sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); if ((so->so_rcv.sb_flags & SB_SPLICED) != 0) xso->so_splice_so = (uintptr_t)so->so_splice->dst; } SOCK_UNLOCK(so); } int so_options_get(const struct socket *so) { return (so->so_options); } void so_options_set(struct socket *so, int val) { so->so_options = val; } int so_error_get(const struct socket *so) { return (so->so_error); } void so_error_set(struct socket *so, int val) { so->so_error = val; }