/* $NetBSD: uipc_socket.c,v 1.281.2.3 2020/09/22 18:39:01 martin Exp $ */ /* * Copyright (c) 2002, 2007, 2008, 2009 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of Wasabi Systems, Inc, and by Andrew Doran. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /* * Copyright (c) 2004 The FreeBSD Foundation * Copyright (c) 2004 Robert Watson * Copyright (c) 1982, 1986, 1988, 1990, 1993 * The Regents of the University of California. 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. * * @(#)uipc_socket.c 8.6 (Berkeley) 5/2/95 */ /* * 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. */ #include __KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.281.2.3 2020/09/22 18:39:01 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_compat_netbsd.h" #include "opt_sock_counters.h" #include "opt_sosend_loan.h" #include "opt_mbuftrace.h" #include "opt_somaxkva.h" #include "opt_multiprocessor.h" /* XXX */ #include "opt_sctp.h" #endif #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 SCTP #include #endif MALLOC_DEFINE(M_SONAME, "soname", "socket name"); extern const struct fileops socketops; static int sooptions; extern int somaxconn; /* patchable (XXX sysctl) */ int somaxconn = SOMAXCONN; kmutex_t *softnet_lock; #ifdef SOSEND_COUNTERS #include static struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "loan big"); static struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "copy big"); static struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "copy small"); static struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "kva limit"); #define SOSEND_COUNTER_INCR(ev) (ev)->ev_count++ EVCNT_ATTACH_STATIC(sosend_loan_big); EVCNT_ATTACH_STATIC(sosend_copy_big); EVCNT_ATTACH_STATIC(sosend_copy_small); EVCNT_ATTACH_STATIC(sosend_kvalimit); #else #define SOSEND_COUNTER_INCR(ev) /* nothing */ #endif /* SOSEND_COUNTERS */ #if defined(SOSEND_NO_LOAN) || defined(MULTIPROCESSOR) int sock_loan_thresh = -1; #else int sock_loan_thresh = 4096; #endif static kmutex_t so_pendfree_lock; static struct mbuf *so_pendfree = NULL; #ifndef SOMAXKVA #define SOMAXKVA (16 * 1024 * 1024) #endif int somaxkva = SOMAXKVA; static int socurkva; static kcondvar_t socurkva_cv; static kauth_listener_t socket_listener; #define SOCK_LOAN_CHUNK 65536 static void sopendfree_thread(void *); static kcondvar_t pendfree_thread_cv; static lwp_t *sopendfree_lwp; static void sysctl_kern_socket_setup(void); static struct sysctllog *socket_sysctllog; static vsize_t sokvareserve(struct socket *so, vsize_t len) { int error; mutex_enter(&so_pendfree_lock); while (socurkva + len > somaxkva) { SOSEND_COUNTER_INCR(&sosend_kvalimit); error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock); if (error) { len = 0; break; } } socurkva += len; mutex_exit(&so_pendfree_lock); return len; } static void sokvaunreserve(vsize_t len) { mutex_enter(&so_pendfree_lock); socurkva -= len; cv_broadcast(&socurkva_cv); mutex_exit(&so_pendfree_lock); } /* * sokvaalloc: allocate kva for loan. */ vaddr_t sokvaalloc(vaddr_t sva, vsize_t len, struct socket *so) { vaddr_t lva; if (sokvareserve(so, len) == 0) return 0; lva = uvm_km_alloc(kernel_map, len, atop(sva) & uvmexp.colormask, UVM_KMF_COLORMATCH | UVM_KMF_VAONLY | UVM_KMF_WAITVA); if (lva == 0) { sokvaunreserve(len); return 0; } return lva; } /* * sokvafree: free kva for loan. */ void sokvafree(vaddr_t sva, vsize_t len) { uvm_km_free(kernel_map, sva, len, UVM_KMF_VAONLY); sokvaunreserve(len); } static void sodoloanfree(struct vm_page **pgs, void *buf, size_t size) { vaddr_t sva, eva; vsize_t len; int npgs; KASSERT(pgs != NULL); eva = round_page((vaddr_t) buf + size); sva = trunc_page((vaddr_t) buf); len = eva - sva; npgs = len >> PAGE_SHIFT; pmap_kremove(sva, len); pmap_update(pmap_kernel()); uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE); sokvafree(sva, len); } /* * sopendfree_thread: free mbufs on "pendfree" list. Unlock and relock * so_pendfree_lock when freeing mbufs. */ static void sopendfree_thread(void *v) { struct mbuf *m, *next; size_t rv; mutex_enter(&so_pendfree_lock); for (;;) { rv = 0; while (so_pendfree != NULL) { m = so_pendfree; so_pendfree = NULL; mutex_exit(&so_pendfree_lock); for (; m != NULL; m = next) { next = m->m_next; KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0); KASSERT(m->m_ext.ext_refcnt == 0); rv += m->m_ext.ext_size; sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf, m->m_ext.ext_size); pool_cache_put(mb_cache, m); } mutex_enter(&so_pendfree_lock); } if (rv) cv_broadcast(&socurkva_cv); cv_wait(&pendfree_thread_cv, &so_pendfree_lock); } panic("sopendfree_thread"); /* NOTREACHED */ } void soloanfree(struct mbuf *m, void *buf, size_t size, void *arg) { KASSERT(m != NULL); /* * postpone freeing mbuf. * * we can't do it in interrupt context * because we need to put kva back to kernel_map. */ mutex_enter(&so_pendfree_lock); m->m_next = so_pendfree; so_pendfree = m; cv_signal(&pendfree_thread_cv); mutex_exit(&so_pendfree_lock); } static long sosend_loan(struct socket *so, struct uio *uio, struct mbuf *m, long space) { struct iovec *iov = uio->uio_iov; vaddr_t sva, eva; vsize_t len; vaddr_t lva; int npgs, error; vaddr_t va; int i; if (VMSPACE_IS_KERNEL_P(uio->uio_vmspace)) return 0; if (iov->iov_len < (size_t) space) space = iov->iov_len; if (space > SOCK_LOAN_CHUNK) space = SOCK_LOAN_CHUNK; eva = round_page((vaddr_t) iov->iov_base + space); sva = trunc_page((vaddr_t) iov->iov_base); len = eva - sva; npgs = len >> PAGE_SHIFT; KASSERT(npgs <= M_EXT_MAXPAGES); lva = sokvaalloc(sva, len, so); if (lva == 0) return 0; error = uvm_loan(&uio->uio_vmspace->vm_map, sva, len, m->m_ext.ext_pgs, UVM_LOAN_TOPAGE); if (error) { sokvafree(lva, len); return 0; } for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE) pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]), VM_PROT_READ, 0); pmap_update(pmap_kernel()); lva += (vaddr_t) iov->iov_base & PAGE_MASK; MEXTADD(m, (void *) lva, space, M_MBUF, soloanfree, so); m->m_flags |= M_EXT_PAGES | M_EXT_ROMAP; uio->uio_resid -= space; /* uio_offset not updated, not set/used for write(2) */ uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + space; uio->uio_iov->iov_len -= space; if (uio->uio_iov->iov_len == 0) { uio->uio_iov++; uio->uio_iovcnt--; } return space; } static int socket_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, void *arg0, void *arg1, void *arg2, void *arg3) { int result; enum kauth_network_req req; result = KAUTH_RESULT_DEFER; req = (enum kauth_network_req)arg0; if ((action != KAUTH_NETWORK_SOCKET) && (action != KAUTH_NETWORK_BIND)) return result; switch (req) { case KAUTH_REQ_NETWORK_BIND_PORT: result = KAUTH_RESULT_ALLOW; break; case KAUTH_REQ_NETWORK_SOCKET_DROP: { /* Normal users can only drop their own connections. */ struct socket *so = (struct socket *)arg1; if (so->so_cred && proc_uidmatch(cred, so->so_cred) == 0) result = KAUTH_RESULT_ALLOW; break; } case KAUTH_REQ_NETWORK_SOCKET_OPEN: /* We allow "raw" routing/bluetooth sockets to anyone. */ switch ((u_long)arg1) { case PF_ROUTE: case PF_OROUTE: case PF_BLUETOOTH: case PF_CAN: result = KAUTH_RESULT_ALLOW; break; default: /* Privileged, let secmodel handle this. */ if ((u_long)arg2 == SOCK_RAW) break; result = KAUTH_RESULT_ALLOW; break; } break; case KAUTH_REQ_NETWORK_SOCKET_CANSEE: result = KAUTH_RESULT_ALLOW; break; default: break; } return result; } void soinit(void) { sysctl_kern_socket_setup(); #ifdef SCTP /* Update the SCTP function hooks if necessary*/ vec_sctp_add_ip_address = sctp_add_ip_address; vec_sctp_delete_ip_address = sctp_delete_ip_address; #endif mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM); softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); cv_init(&socurkva_cv, "sokva"); cv_init(&pendfree_thread_cv, "sopendfr"); soinit2(); /* Set the initial adjusted socket buffer size. */ if (sb_max_set(sb_max)) panic("bad initial sb_max value: %lu", sb_max); socket_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK, socket_listener_cb, NULL); } void soinit1(void) { int error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, sopendfree_thread, NULL, &sopendfree_lwp, "sopendfree"); if (error) panic("soinit1 %d", error); } /* * socreate: create a new socket of the specified type and the protocol. * * => Caller may specify another socket for lock sharing (must not be held). * => Returns the new socket without lock held. */ int socreate(int dom, struct socket **aso, int type, int proto, struct lwp *l, struct socket *lockso) { const struct protosw *prp; struct socket *so; uid_t uid; int error; kmutex_t *lock; error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET, KAUTH_REQ_NETWORK_SOCKET_OPEN, KAUTH_ARG(dom), KAUTH_ARG(type), KAUTH_ARG(proto)); if (error != 0) return error; if (proto) prp = pffindproto(dom, proto, type); else prp = pffindtype(dom, type); if (prp == NULL) { /* no support for domain */ if (pffinddomain(dom) == 0) return EAFNOSUPPORT; /* no support for socket type */ if (proto == 0 && type != 0) return EPROTOTYPE; return EPROTONOSUPPORT; } if (prp->pr_usrreqs == NULL) return EPROTONOSUPPORT; if (prp->pr_type != type) return EPROTOTYPE; so = soget(true); so->so_type = type; so->so_proto = prp; so->so_send = sosend; so->so_receive = soreceive; so->so_options = sooptions; #ifdef MBUFTRACE so->so_rcv.sb_mowner = &prp->pr_domain->dom_mowner; so->so_snd.sb_mowner = &prp->pr_domain->dom_mowner; so->so_mowner = &prp->pr_domain->dom_mowner; #endif uid = kauth_cred_geteuid(l->l_cred); so->so_uidinfo = uid_find(uid); so->so_egid = kauth_cred_getegid(l->l_cred); so->so_cpid = l->l_proc->p_pid; /* * Lock assigned and taken during PCB attach, unless we share * the lock with another socket, e.g. socketpair(2) case. */ if (lockso) { lock = lockso->so_lock; so->so_lock = lock; mutex_obj_hold(lock); mutex_enter(lock); } /* Attach the PCB (returns with the socket lock held). */ error = (*prp->pr_usrreqs->pr_attach)(so, proto); KASSERT(solocked(so)); if (error) { KASSERT(so->so_pcb == NULL); so->so_state |= SS_NOFDREF; sofree(so); return error; } so->so_cred = kauth_cred_dup(l->l_cred); sounlock(so); *aso = so; return 0; } /* * fsocreate: create a socket and a file descriptor associated with it. * * => On success, write file descriptor to fdout and return zero. * => On failure, return non-zero; *fdout will be undefined. */ int fsocreate(int domain, struct socket **sop, int type, int proto, int *fdout) { lwp_t *l = curlwp; int error, fd, flags; struct socket *so; struct file *fp; if ((error = fd_allocfile(&fp, &fd)) != 0) { return error; } flags = type & SOCK_FLAGS_MASK; fd_set_exclose(l, fd, (flags & SOCK_CLOEXEC) != 0); fp->f_flag = FREAD|FWRITE|((flags & SOCK_NONBLOCK) ? FNONBLOCK : 0)| ((flags & SOCK_NOSIGPIPE) ? FNOSIGPIPE : 0); fp->f_type = DTYPE_SOCKET; fp->f_ops = &socketops; type &= ~SOCK_FLAGS_MASK; error = socreate(domain, &so, type, proto, l, NULL); if (error) { fd_abort(curproc, fp, fd); return error; } if (flags & SOCK_NONBLOCK) { so->so_state |= SS_NBIO; } fp->f_socket = so; fd_affix(curproc, fp, fd); if (sop != NULL) { *sop = so; } *fdout = fd; return error; } int sofamily(const struct socket *so) { const struct protosw *pr; const struct domain *dom; if ((pr = so->so_proto) == NULL) return AF_UNSPEC; if ((dom = pr->pr_domain) == NULL) return AF_UNSPEC; return dom->dom_family; } int sobind(struct socket *so, struct sockaddr *nam, struct lwp *l) { int error; solock(so); if (nam->sa_family != so->so_proto->pr_domain->dom_family) { sounlock(so); return EAFNOSUPPORT; } error = (*so->so_proto->pr_usrreqs->pr_bind)(so, nam, l); sounlock(so); return error; } int solisten(struct socket *so, int backlog, struct lwp *l) { int error; short oldopt, oldqlimit; solock(so); if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) != 0) { sounlock(so); return EINVAL; } oldopt = so->so_options; oldqlimit = so->so_qlimit; if (TAILQ_EMPTY(&so->so_q)) so->so_options |= SO_ACCEPTCONN; if (backlog < 0) backlog = 0; so->so_qlimit = uimin(backlog, somaxconn); error = (*so->so_proto->pr_usrreqs->pr_listen)(so, l); if (error != 0) { so->so_options = oldopt; so->so_qlimit = oldqlimit; sounlock(so); return error; } sounlock(so); return 0; } void sofree(struct socket *so) { u_int refs; KASSERT(solocked(so)); if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) { sounlock(so); return; } if (so->so_head) { /* * We must not decommission a socket that's on the accept(2) * queue. If we do, then accept(2) may hang after select(2) * indicated that the listening socket was ready. */ if (!soqremque(so, 0)) { sounlock(so); return; } } if (so->so_rcv.sb_hiwat) (void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); if (so->so_snd.sb_hiwat) (void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); sbrelease(&so->so_snd, so); KASSERT(!cv_has_waiters(&so->so_cv)); KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv)); KASSERT(!cv_has_waiters(&so->so_snd.sb_cv)); sorflush(so); refs = so->so_aborting; /* XXX */ /* Remove acccept filter if one is present. */ if (so->so_accf != NULL) (void)accept_filt_clear(so); sounlock(so); if (refs == 0) /* XXX */ soput(so); } /* * soclose: close a socket on last file table reference removal. * Initiate disconnect if connected. Free socket when disconnect complete. */ int soclose(struct socket *so) { struct socket *so2; int error = 0; solock(so); if (so->so_options & SO_ACCEPTCONN) { for (;;) { if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) { KASSERT(solocked2(so, so2)); (void) soqremque(so2, 0); /* soabort drops the lock. */ (void) soabort(so2); solock(so); continue; } if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) { KASSERT(solocked2(so, so2)); (void) soqremque(so2, 1); /* soabort drops the lock. */ (void) soabort(so2); solock(so); continue; } break; } } if (so->so_pcb == NULL) goto discard; if (so->so_state & SS_ISCONNECTED) { if ((so->so_state & SS_ISDISCONNECTING) == 0) { error = sodisconnect(so); if (error) goto drop; } if (so->so_options & SO_LINGER) { if ((so->so_state & (SS_ISDISCONNECTING|SS_NBIO)) == (SS_ISDISCONNECTING|SS_NBIO)) goto drop; while (so->so_state & SS_ISCONNECTED) { error = sowait(so, true, so->so_linger * hz); if (error) break; } } } drop: if (so->so_pcb) { KASSERT(solocked(so)); (*so->so_proto->pr_usrreqs->pr_detach)(so); } discard: KASSERT((so->so_state & SS_NOFDREF) == 0); kauth_cred_free(so->so_cred); so->so_cred = NULL; so->so_state |= SS_NOFDREF; sofree(so); return error; } /* * Must be called with the socket locked.. Will return with it unlocked. */ int soabort(struct socket *so) { u_int refs; int error; KASSERT(solocked(so)); KASSERT(so->so_head == NULL); so->so_aborting++; /* XXX */ error = (*so->so_proto->pr_usrreqs->pr_abort)(so); refs = --so->so_aborting; /* XXX */ if (error || (refs == 0)) { sofree(so); } else { sounlock(so); } return error; } int soaccept(struct socket *so, struct sockaddr *nam) { int error; KASSERT(solocked(so)); KASSERT((so->so_state & SS_NOFDREF) != 0); so->so_state &= ~SS_NOFDREF; if ((so->so_state & SS_ISDISCONNECTED) == 0 || (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0) error = (*so->so_proto->pr_usrreqs->pr_accept)(so, nam); else error = ECONNABORTED; return error; } int soconnect(struct socket *so, struct sockaddr *nam, struct lwp *l) { int error; KASSERT(solocked(so)); if (so->so_options & SO_ACCEPTCONN) return EOPNOTSUPP; /* * 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. */ if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && ((so->so_proto->pr_flags & PR_CONNREQUIRED) || (error = sodisconnect(so)))) { error = EISCONN; } else { if (nam->sa_family != so->so_proto->pr_domain->dom_family) { return EAFNOSUPPORT; } error = (*so->so_proto->pr_usrreqs->pr_connect)(so, nam, l); } return error; } int soconnect2(struct socket *so1, struct socket *so2) { KASSERT(solocked2(so1, so2)); return (*so1->so_proto->pr_usrreqs->pr_connect2)(so1, so2); } int sodisconnect(struct socket *so) { int error; KASSERT(solocked(so)); if ((so->so_state & SS_ISCONNECTED) == 0) { error = ENOTCONN; } else if (so->so_state & SS_ISDISCONNECTING) { error = EALREADY; } else { error = (*so->so_proto->pr_usrreqs->pr_disconnect)(so); } return error; } #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK) /* * 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. */ int sosend(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct lwp *l) { struct mbuf **mp, *m; long space, len, resid, clen, mlen; int error, s, dontroute, atomic; short wakeup_state = 0; clen = 0; /* * solock() provides atomicity of access. splsoftnet() prevents * protocol processing soft interrupts from interrupting us and * blocking (expensive). */ s = splsoftnet(); solock(so); atomic = sosendallatonce(so) || top; if (uio) 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 && (so->so_proto->pr_flags & PR_ATOMIC); l->l_ru.ru_msgsnd++; if (control) clen = control->m_len; restart: if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0) goto out; do { if (so->so_state & SS_CANTSENDMORE) { error = EPIPE; goto release; } if (so->so_error) { error = so->so_error; so->so_error = 0; goto release; } if ((so->so_state & SS_ISCONNECTED) == 0) { if (so->so_proto->pr_flags & PR_CONNREQUIRED) { if (resid || clen == 0) { error = ENOTCONN; goto release; } } else if (addr == NULL) { error = EDESTADDRREQ; goto release; } } 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) { error = EMSGSIZE; goto release; } if (space < resid + clen && (atomic || space < so->so_snd.sb_lowat || space < clen)) { if ((so->so_state & SS_NBIO) || (flags & MSG_NBIO)) { error = EWOULDBLOCK; goto release; } sbunlock(&so->so_snd); if (wakeup_state & SS_RESTARTSYS) { error = ERESTART; goto out; } error = sbwait(&so->so_snd); if (error) goto out; wakeup_state = so->so_state; goto restart; } wakeup_state = 0; mp = ⊤ space -= clen; do { if (uio == NULL) { /* * Data is prepackaged in "top". */ resid = 0; if (flags & MSG_EOR) top->m_flags |= M_EOR; } else do { sounlock(so); splx(s); if (top == NULL) { m = m_gethdr(M_WAIT, MT_DATA); mlen = MHLEN; m->m_pkthdr.len = 0; m_reset_rcvif(m); } else { m = m_get(M_WAIT, MT_DATA); mlen = MLEN; } MCLAIM(m, so->so_snd.sb_mowner); if (sock_loan_thresh >= 0 && uio->uio_iov->iov_len >= sock_loan_thresh && space >= sock_loan_thresh && (len = sosend_loan(so, uio, m, space)) != 0) { SOSEND_COUNTER_INCR(&sosend_loan_big); space -= len; goto have_data; } if (resid >= MINCLSIZE && space >= MCLBYTES) { SOSEND_COUNTER_INCR(&sosend_copy_big); m_clget(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) goto nopages; mlen = MCLBYTES; if (atomic && top == 0) { len = lmin(MCLBYTES - max_hdr, resid); m->m_data += max_hdr; } else len = lmin(MCLBYTES, resid); space -= len; } else { nopages: SOSEND_COUNTER_INCR(&sosend_copy_small); len = lmin(lmin(mlen, resid), space); space -= len; /* * For datagram protocols, leave room * for protocol headers in first mbuf. */ if (atomic && top == 0 && len < mlen) m_align(m, len); } error = uiomove(mtod(m, void *), (int)len, uio); have_data: resid = uio->uio_resid; m->m_len = len; *mp = m; top->m_pkthdr.len += len; s = splsoftnet(); solock(so); if (error != 0) goto release; mp = &m->m_next; if (resid <= 0) { if (flags & MSG_EOR) top->m_flags |= M_EOR; break; } } while (space > 0 && atomic); if (so->so_state & SS_CANTSENDMORE) { error = EPIPE; goto release; } if (dontroute) so->so_options |= SO_DONTROUTE; if (resid > 0) so->so_state |= SS_MORETOCOME; if (flags & MSG_OOB) { error = (*so->so_proto->pr_usrreqs->pr_sendoob)( so, top, control); } else { error = (*so->so_proto->pr_usrreqs->pr_send)(so, top, addr, control, l); } if (dontroute) so->so_options &= ~SO_DONTROUTE; if (resid > 0) so->so_state &= ~SS_MORETOCOME; clen = 0; control = NULL; top = NULL; mp = ⊤ if (error != 0) goto release; } while (resid && space > 0); } while (resid); release: sbunlock(&so->so_snd); out: sounlock(so); splx(s); if (top) m_freem(top); if (control) m_freem(control); 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 caller's 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 void sbsync(struct sockbuf *sb, struct mbuf *nextrecord) { KASSERT(solocked(sb->sb_so)); /* * 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 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 avoid blocking network interrupts for the entire time here, we * splx() while doing the actual copy to user space. 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. */ int soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { struct lwp *l = curlwp; struct mbuf *m, **mp, *mt; size_t len, offset, moff, orig_resid; int atomic, flags, error, s, type; const struct protosw *pr; struct mbuf *nextrecord; int mbuf_removed = 0; const struct domain *dom; short wakeup_state = 0; pr = so->so_proto; atomic = pr->pr_flags & PR_ATOMIC; dom = pr->pr_domain; mp = mp0; type = 0; orig_resid = uio->uio_resid; if (paddr != NULL) *paddr = NULL; if (controlp != NULL) *controlp = NULL; if (flagsp != NULL) flags = *flagsp &~ MSG_EOR; else flags = 0; if (flags & MSG_OOB) { m = m_get(M_WAIT, MT_DATA); solock(so); error = (*pr->pr_usrreqs->pr_recvoob)(so, m, flags & MSG_PEEK); sounlock(so); if (error) goto bad; do { error = uiomove(mtod(m, void *), MIN(uio->uio_resid, m->m_len), uio); m = m_free(m); } while (uio->uio_resid > 0 && error == 0 && m); bad: if (m != NULL) m_freem(m); return error; } if (mp != NULL) *mp = NULL; /* * solock() provides atomicity of access. splsoftnet() prevents * protocol processing soft interrupts from interrupting us and * blocking (expensive). */ s = splsoftnet(); solock(so); restart: if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) { sounlock(so); splx(s); return error; } 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, * 2. MSG_WAITALL is set, and it is possible to do the entire * receive operation at once if we block (resid <= hiwat), or * 3. MSG_DONTWAIT is not set. * If MSG_WAITALL is set but resid is larger than the receive buffer, * we have to do the receive in sections, and thus risk returning * a short count if a timeout or signal occurs after we start. */ if (m == NULL || ((flags & MSG_DONTWAIT) == 0 && so->so_rcv.sb_cc < uio->uio_resid && (so->so_rcv.sb_cc < so->so_rcv.sb_lowat || ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) && m->m_nextpkt == NULL && !atomic)) { #ifdef DIAGNOSTIC if (m == NULL && so->so_rcv.sb_cc) panic("receive 1"); #endif if (so->so_error || so->so_rerror) { if (m != NULL) goto dontblock; if (so->so_error) { error = so->so_error; so->so_error = 0; } else { error = so->so_rerror; so->so_rerror = 0; } goto release; } if (so->so_state & SS_CANTRCVMORE) { if (m != NULL) goto dontblock; else 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_ISCONNECTED|SS_ISCONNECTING)) == 0 && (so->so_proto->pr_flags & PR_CONNREQUIRED)) { error = ENOTCONN; goto release; } if (uio->uio_resid == 0) goto release; if ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO))) { error = EWOULDBLOCK; goto release; } SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1"); sbunlock(&so->so_rcv); if (wakeup_state & SS_RESTARTSYS) error = ERESTART; else error = sbwait(&so->so_rcv); if (error != 0) { sounlock(so); splx(s); return error; } wakeup_state = so->so_state; goto restart; } dontblock: /* * On entry here, m points to the first record of the socket buffer. * 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 lock, 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. */ if (l != NULL) l->l_ru.ru_msgrcv++; KASSERT(m == so->so_rcv.sb_mb); SBLASTRECORDCHK(&so->so_rcv, "soreceive 1"); SBLASTMBUFCHK(&so->so_rcv, "soreceive 1"); nextrecord = m->m_nextpkt; if (pr->pr_flags & PR_ADDR) { KASSERT(m->m_type == MT_SONAME); orig_resid = 0; if (flags & MSG_PEEK) { if (paddr) *paddr = m_copym(m, 0, m->m_len, M_DONTWAIT); m = m->m_next; } else { sbfree(&so->so_rcv, m); mbuf_removed = 1; if (paddr != NULL) { *paddr = m; so->so_rcv.sb_mb = m->m_next; m->m_next = NULL; m = so->so_rcv.sb_mb; } else { m = so->so_rcv.sb_mb = m_free(m); } sbsync(&so->so_rcv, nextrecord); } } if (pr->pr_flags & PR_ADDR_OPT) { /* * For SCTP we may be getting a whole message OR a partial * delivery. */ if (m->m_type == MT_SONAME) { orig_resid = 0; if (flags & MSG_PEEK) { if (paddr) *paddr = m_copym(m, 0, m->m_len, M_DONTWAIT); m = m->m_next; } else { sbfree(&so->so_rcv, m); /* XXX XXX XXX: should set mbuf_removed? */ if (paddr) { *paddr = m; so->so_rcv.sb_mb = m->m_next; m->m_next = 0; m = so->so_rcv.sb_mb; } else { m = so->so_rcv.sb_mb = m_free(m); } /* XXX XXX XXX: isn't there an sbsync() * missing here? */ } } } /* * 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 (__predict_false(m != NULL && m->m_type == MT_CONTROL)) { struct mbuf *cm = NULL, *cmn; struct mbuf **cme = &cm; do { if (flags & MSG_PEEK) { if (controlp != NULL) { *controlp = m_copym(m, 0, m->m_len, M_DONTWAIT); 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) sbsync(&so->so_rcv, nextrecord); for (; cm != NULL; cm = cmn) { cmn = cm->m_next; cm->m_next = NULL; type = mtod(cm, struct cmsghdr *)->cmsg_type; if (controlp != NULL) { if (dom->dom_externalize != NULL && type == SCM_RIGHTS) { sounlock(so); splx(s); error = (*dom->dom_externalize)(cm, l, (flags & MSG_CMSG_CLOEXEC) ? O_CLOEXEC : 0); s = splsoftnet(); solock(so); } *controlp = cm; while (*controlp != NULL) controlp = &(*controlp)->m_next; } else { /* * Dispose of any SCM_RIGHTS message that went * through the read path rather than recv. */ if (dom->dom_dispose != NULL && type == SCM_RIGHTS) { sounlock(so); (*dom->dom_dispose)(cm); solock(so); } m_freem(cm); } } if (m != NULL) nextrecord = so->so_rcv.sb_mb->m_nextpkt; else nextrecord = so->so_rcv.sb_mb; orig_resid = 0; } /* If m is non-NULL, we have some data to read. */ if (__predict_true(m != NULL)) { type = m->m_type; if (type == MT_OOBDATA) flags |= MSG_OOB; } SBLASTRECORDCHK(&so->so_rcv, "soreceive 2"); SBLASTMBUFCHK(&so->so_rcv, "soreceive 2"); moff = 0; offset = 0; while (m != NULL && uio->uio_resid > 0 && error == 0) { /* * If the type of mbuf has changed, end the receive * operation and do a short read. */ if (m->m_type == MT_OOBDATA) { if (type != MT_OOBDATA) break; } else if (type == MT_OOBDATA) { break; } else if (m->m_type == MT_CONTROL) { break; } #ifdef DIAGNOSTIC else if (m->m_type != MT_DATA && m->m_type != MT_HEADER) { panic("%s: m_type=%d", __func__, m->m_type); } #endif so->so_state &= ~SS_RCVATMARK; wakeup_state = 0; 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) { SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove"); SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove"); sounlock(so); splx(s); error = uiomove(mtod(m, char *) + moff, len, uio); s = splsoftnet(); solock(so); if (error != 0) { /* * If any part of the record has been removed * (such as the MT_SONAME mbuf, which will * happen when PR_ADDR, and thus also * PR_ATOMIC, is set), then drop the entire * record to maintain the atomicity of the * receive operation. * * This avoids a later panic("receive 1a") * when compiled with DIAGNOSTIC. */ if (m && mbuf_removed && atomic) (void) sbdroprecord(&so->so_rcv); goto release; } } else { uio->uio_resid -= len; } if (len == m->m_len - moff) { if (m->m_flags & M_EOR) flags |= MSG_EOR; #ifdef SCTP if (m->m_flags & M_NOTIFICATION) flags |= MSG_NOTIFICATION; #endif if (flags & MSG_PEEK) { m = m->m_next; moff = 0; } else { nextrecord = m->m_nextpkt; sbfree(&so->so_rcv, m); if (mp) { *mp = m; mp = &m->m_next; so->so_rcv.sb_mb = m = m->m_next; *mp = NULL; } else { m = so->so_rcv.sb_mb = m_free(m); } /* * If m != NULL, we also know that * so->so_rcv.sb_mb != NULL. */ KASSERT(so->so_rcv.sb_mb == m); if (m) { m->m_nextpkt = nextrecord; if (nextrecord == NULL) so->so_rcv.sb_lastrecord = m; } else { so->so_rcv.sb_mb = nextrecord; SB_EMPTY_FIXUP(&so->so_rcv); } SBLASTRECORDCHK(&so->so_rcv, "soreceive 3"); SBLASTMBUFCHK(&so->so_rcv, "soreceive 3"); } } else if (flags & MSG_PEEK) { moff += len; } else { if (mp != NULL) { mt = m_copym(m, 0, len, M_NOWAIT); if (__predict_false(mt == NULL)) { sounlock(so); mt = m_copym(m, 0, len, M_WAIT); solock(so); } *mp = mt; } m->m_data += len; m->m_len -= len; so->so_rcv.sb_cc -= len; } if (so->so_oobmark) { if ((flags & MSG_PEEK) == 0) { so->so_oobmark -= len; if (so->so_oobmark == 0) { so->so_state |= SS_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) { if (so->so_error || so->so_rerror || so->so_state & SS_CANTRCVMORE) break; /* * If we are peeking and the socket receive buffer is * full, stop since we can't get more data to peek at. */ if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0) break; /* * If we've drained the socket buffer, tell the * protocol in case it needs to do something to * get it filled again. */ if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb) (*pr->pr_usrreqs->pr_rcvd)(so, flags, l); SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2"); if (wakeup_state & SS_RESTARTSYS) error = ERESTART; else error = sbwait(&so->so_rcv); if (error != 0) { sbunlock(&so->so_rcv); sounlock(so); splx(s); return 0; } if ((m = so->so_rcv.sb_mb) != NULL) nextrecord = m->m_nextpkt; wakeup_state = so->so_state; } } if (m && atomic) { flags |= MSG_TRUNC; if ((flags & MSG_PEEK) == 0) (void) sbdroprecord(&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, "soreceive 4"); SBLASTMBUFCHK(&so->so_rcv, "soreceive 4"); if (pr->pr_flags & PR_WANTRCVD && so->so_pcb) (*pr->pr_usrreqs->pr_rcvd)(so, flags, l); } if (orig_resid == uio->uio_resid && orig_resid && (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) { sbunlock(&so->so_rcv); goto restart; } if (flagsp != NULL) *flagsp |= flags; release: sbunlock(&so->so_rcv); sounlock(so); splx(s); return error; } int soshutdown(struct socket *so, int how) { const struct protosw *pr; int error; KASSERT(solocked(so)); pr = so->so_proto; if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) return EINVAL; if (how == SHUT_RD || how == SHUT_RDWR) { sorflush(so); error = 0; } if (how == SHUT_WR || how == SHUT_RDWR) error = (*pr->pr_usrreqs->pr_shutdown)(so); return error; } void sorestart(struct socket *so) { /* * An application has called close() on an fd on which another * of its threads has called a socket system call. * Mark this and wake everyone up, and code that would block again * instead returns ERESTART. * On system call re-entry the fd is validated and EBADF returned. * Any other fd will block again on the 2nd syscall. */ solock(so); so->so_state |= SS_RESTARTSYS; cv_broadcast(&so->so_cv); cv_broadcast(&so->so_snd.sb_cv); cv_broadcast(&so->so_rcv.sb_cv); sounlock(so); } void sorflush(struct socket *so) { struct sockbuf *sb, asb; const struct protosw *pr; KASSERT(solocked(so)); sb = &so->so_rcv; pr = so->so_proto; socantrcvmore(so); sb->sb_flags |= SB_NOINTR; (void )sblock(sb, M_WAITOK); sbunlock(sb); asb = *sb; /* * Clear most of the sockbuf structure, but leave some of the * fields valid. */ memset(&sb->sb_startzero, 0, sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) { sounlock(so); (*pr->pr_domain->dom_dispose)(asb.sb_mb); solock(so); } sbrelease(&asb, so); } /* * internal set SOL_SOCKET options */ static int sosetopt1(struct socket *so, const struct sockopt *sopt) { int error, opt; int optval = 0; /* XXX: gcc */ struct linger l; struct timeval tv; opt = sopt->sopt_name; switch (opt) { case SO_ACCEPTFILTER: error = accept_filt_setopt(so, sopt); KASSERT(solocked(so)); break; case SO_LINGER: error = sockopt_get(sopt, &l, sizeof(l)); solock(so); if (error) break; if (l.l_linger < 0 || l.l_linger > USHRT_MAX || l.l_linger > (INT_MAX / hz)) { error = EDOM; break; } so->so_linger = l.l_linger; if (l.l_onoff) so->so_options |= SO_LINGER; else so->so_options &= ~SO_LINGER; break; case SO_DEBUG: case SO_KEEPALIVE: case SO_DONTROUTE: case SO_USELOOPBACK: case SO_BROADCAST: case SO_REUSEADDR: case SO_REUSEPORT: case SO_OOBINLINE: case SO_TIMESTAMP: case SO_NOSIGPIPE: case SO_RERROR: error = sockopt_getint(sopt, &optval); solock(so); if (error) break; if (optval) so->so_options |= opt; else so->so_options &= ~opt; break; case SO_SNDBUF: case SO_RCVBUF: case SO_SNDLOWAT: case SO_RCVLOWAT: error = sockopt_getint(sopt, &optval); solock(so); if (error) break; /* * Values < 1 make no sense for any of these * options, so disallow them. */ if (optval < 1) { error = EINVAL; break; } switch (opt) { case SO_SNDBUF: if (sbreserve(&so->so_snd, (u_long)optval, so) == 0) { error = ENOBUFS; break; } so->so_snd.sb_flags &= ~SB_AUTOSIZE; break; case SO_RCVBUF: if (sbreserve(&so->so_rcv, (u_long)optval, so) == 0) { error = ENOBUFS; break; } so->so_rcv.sb_flags &= ~SB_AUTOSIZE; break; /* * Make sure the low-water is never greater than * the high-water. */ case SO_SNDLOWAT: if (optval > so->so_snd.sb_hiwat) optval = so->so_snd.sb_hiwat; so->so_snd.sb_lowat = optval; break; case SO_RCVLOWAT: if (optval > so->so_rcv.sb_hiwat) optval = so->so_rcv.sb_hiwat; so->so_rcv.sb_lowat = optval; break; } break; case SO_SNDTIMEO: case SO_RCVTIMEO: solock(so); error = sockopt_get(sopt, &tv, sizeof(tv)); if (error) break; if (tv.tv_sec < 0 || tv.tv_usec < 0 || tv.tv_usec >= 1000000) { error = EDOM; break; } if (tv.tv_sec > (INT_MAX - tv.tv_usec / tick) / hz) { error = EDOM; break; } optval = tv.tv_sec * hz + tv.tv_usec / tick; if (optval == 0 && tv.tv_usec != 0) optval = 1; switch (opt) { case SO_SNDTIMEO: so->so_snd.sb_timeo = optval; break; case SO_RCVTIMEO: so->so_rcv.sb_timeo = optval; break; } break; default: MODULE_HOOK_CALL(uipc_socket_50_setopt1_hook, (opt, so, sopt), enosys(), error); if (error == ENOSYS || error == EPASSTHROUGH) { solock(so); error = ENOPROTOOPT; } break; } KASSERT(solocked(so)); return error; } int sosetopt(struct socket *so, struct sockopt *sopt) { int error, prerr; if (sopt->sopt_level == SOL_SOCKET) { error = sosetopt1(so, sopt); KASSERT(solocked(so)); } else { error = ENOPROTOOPT; solock(so); } if ((error == 0 || error == ENOPROTOOPT) && so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) { /* give the protocol stack a shot */ prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, sopt); if (prerr == 0) error = 0; else if (prerr != ENOPROTOOPT) error = prerr; } sounlock(so); return error; } /* * so_setsockopt() is a wrapper providing a sockopt structure for sosetopt() */ int so_setsockopt(struct lwp *l, struct socket *so, int level, int name, const void *val, size_t valsize) { struct sockopt sopt; int error; KASSERT(valsize == 0 || val != NULL); sockopt_init(&sopt, level, name, valsize); sockopt_set(&sopt, val, valsize); error = sosetopt(so, &sopt); sockopt_destroy(&sopt); return error; } /* * internal get SOL_SOCKET options */ static int sogetopt1(struct socket *so, struct sockopt *sopt) { int error, optval, opt; struct linger l; struct timeval tv; switch ((opt = sopt->sopt_name)) { case SO_ACCEPTFILTER: error = accept_filt_getopt(so, sopt); break; case SO_LINGER: l.l_onoff = (so->so_options & SO_LINGER) ? 1 : 0; l.l_linger = so->so_linger; error = sockopt_set(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_BROADCAST: case SO_OOBINLINE: case SO_TIMESTAMP: case SO_NOSIGPIPE: case SO_RERROR: case SO_ACCEPTCONN: error = sockopt_setint(sopt, (so->so_options & opt) ? 1 : 0); break; case SO_TYPE: error = sockopt_setint(sopt, so->so_type); break; case SO_ERROR: if (so->so_error == 0) { so->so_error = so->so_rerror; so->so_rerror = 0; } error = sockopt_setint(sopt, so->so_error); so->so_error = 0; break; case SO_SNDBUF: error = sockopt_setint(sopt, so->so_snd.sb_hiwat); break; case SO_RCVBUF: error = sockopt_setint(sopt, so->so_rcv.sb_hiwat); break; case SO_SNDLOWAT: error = sockopt_setint(sopt, so->so_snd.sb_lowat); break; case SO_RCVLOWAT: error = sockopt_setint(sopt, so->so_rcv.sb_lowat); break; case SO_SNDTIMEO: case SO_RCVTIMEO: optval = (opt == SO_SNDTIMEO ? so->so_snd.sb_timeo : so->so_rcv.sb_timeo); memset(&tv, 0, sizeof(tv)); tv.tv_sec = optval / hz; tv.tv_usec = (optval % hz) * tick; error = sockopt_set(sopt, &tv, sizeof(tv)); break; case SO_OVERFLOWED: error = sockopt_setint(sopt, so->so_rcv.sb_overflowed); break; default: MODULE_HOOK_CALL(uipc_socket_50_getopt1_hook, (opt, so, sopt), enosys(), error); if (error) error = ENOPROTOOPT; break; } return error; } int sogetopt(struct socket *so, struct sockopt *sopt) { int error; solock(so); if (sopt->sopt_level != SOL_SOCKET) { if (so->so_proto && so->so_proto->pr_ctloutput) { error = ((*so->so_proto->pr_ctloutput) (PRCO_GETOPT, so, sopt)); } else error = (ENOPROTOOPT); } else { error = sogetopt1(so, sopt); } sounlock(so); return error; } /* * alloc sockopt data buffer buffer * - will be released at destroy */ static int sockopt_alloc(struct sockopt *sopt, size_t len, km_flag_t kmflag) { KASSERT(sopt->sopt_size == 0); if (len > sizeof(sopt->sopt_buf)) { sopt->sopt_data = kmem_zalloc(len, kmflag); if (sopt->sopt_data == NULL) return ENOMEM; } else sopt->sopt_data = sopt->sopt_buf; sopt->sopt_size = len; return 0; } /* * initialise sockopt storage * - MAY sleep during allocation */ void sockopt_init(struct sockopt *sopt, int level, int name, size_t size) { memset(sopt, 0, sizeof(*sopt)); sopt->sopt_level = level; sopt->sopt_name = name; (void)sockopt_alloc(sopt, size, KM_SLEEP); } /* * destroy sockopt storage * - will release any held memory references */ void sockopt_destroy(struct sockopt *sopt) { if (sopt->sopt_data != sopt->sopt_buf) kmem_free(sopt->sopt_data, sopt->sopt_size); memset(sopt, 0, sizeof(*sopt)); } /* * set sockopt value * - value is copied into sockopt * - memory is allocated when necessary, will not sleep */ int sockopt_set(struct sockopt *sopt, const void *buf, size_t len) { int error; if (sopt->sopt_size == 0) { error = sockopt_alloc(sopt, len, KM_NOSLEEP); if (error) return error; } sopt->sopt_retsize = MIN(sopt->sopt_size, len); memcpy(sopt->sopt_data, buf, sopt->sopt_retsize); return 0; } /* * common case of set sockopt integer value */ int sockopt_setint(struct sockopt *sopt, int val) { return sockopt_set(sopt, &val, sizeof(int)); } /* * get sockopt value * - correct size must be given */ int sockopt_get(const struct sockopt *sopt, void *buf, size_t len) { if (sopt->sopt_size != len) return EINVAL; memcpy(buf, sopt->sopt_data, len); return 0; } /* * common case of get sockopt integer value */ int sockopt_getint(const struct sockopt *sopt, int *valp) { return sockopt_get(sopt, valp, sizeof(int)); } /* * set sockopt value from mbuf * - ONLY for legacy code * - mbuf is released by sockopt * - will not sleep */ int sockopt_setmbuf(struct sockopt *sopt, struct mbuf *m) { size_t len; int error; len = m_length(m); if (sopt->sopt_size == 0) { error = sockopt_alloc(sopt, len, KM_NOSLEEP); if (error) return error; } sopt->sopt_retsize = MIN(sopt->sopt_size, len); m_copydata(m, 0, sopt->sopt_retsize, sopt->sopt_data); m_freem(m); return 0; } /* * get sockopt value into mbuf * - ONLY for legacy code * - mbuf to be released by the caller * - will not sleep */ struct mbuf * sockopt_getmbuf(const struct sockopt *sopt) { struct mbuf *m; if (sopt->sopt_size > MCLBYTES) return NULL; m = m_get(M_DONTWAIT, MT_SOOPTS); if (m == NULL) return NULL; if (sopt->sopt_size > MLEN) { MCLGET(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); return NULL; } } memcpy(mtod(m, void *), sopt->sopt_data, sopt->sopt_size); m->m_len = sopt->sopt_size; return m; } void sohasoutofband(struct socket *so) { fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so); selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, NOTE_SUBMIT); } static void filt_sordetach(struct knote *kn) { struct socket *so; so = ((file_t *)kn->kn_obj)->f_socket; solock(so); SLIST_REMOVE(&so->so_rcv.sb_sel.sel_klist, kn, knote, kn_selnext); if (SLIST_EMPTY(&so->so_rcv.sb_sel.sel_klist)) so->so_rcv.sb_flags &= ~SB_KNOTE; sounlock(so); } /*ARGSUSED*/ static int filt_soread(struct knote *kn, long hint) { struct socket *so; int rv; so = ((file_t *)kn->kn_obj)->f_socket; if (hint != NOTE_SUBMIT) solock(so); kn->kn_data = so->so_rcv.sb_cc; if (so->so_state & SS_CANTRCVMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; rv = 1; } else if (so->so_error || so->so_rerror) rv = 1; else if (kn->kn_sfflags & NOTE_LOWAT) rv = (kn->kn_data >= kn->kn_sdata); else rv = (kn->kn_data >= so->so_rcv.sb_lowat); if (hint != NOTE_SUBMIT) sounlock(so); return rv; } static void filt_sowdetach(struct knote *kn) { struct socket *so; so = ((file_t *)kn->kn_obj)->f_socket; solock(so); SLIST_REMOVE(&so->so_snd.sb_sel.sel_klist, kn, knote, kn_selnext); if (SLIST_EMPTY(&so->so_snd.sb_sel.sel_klist)) so->so_snd.sb_flags &= ~SB_KNOTE; sounlock(so); } /*ARGSUSED*/ static int filt_sowrite(struct knote *kn, long hint) { struct socket *so; int rv; so = ((file_t *)kn->kn_obj)->f_socket; if (hint != NOTE_SUBMIT) solock(so); kn->kn_data = sbspace(&so->so_snd); if (so->so_state & SS_CANTSENDMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; rv = 1; } else if (so->so_error) rv = 1; else if (((so->so_state & SS_ISCONNECTED) == 0) && (so->so_proto->pr_flags & PR_CONNREQUIRED)) rv = 0; else if (kn->kn_sfflags & NOTE_LOWAT) rv = (kn->kn_data >= kn->kn_sdata); else rv = (kn->kn_data >= so->so_snd.sb_lowat); if (hint != NOTE_SUBMIT) sounlock(so); return rv; } /*ARGSUSED*/ static int filt_solisten(struct knote *kn, long hint) { struct socket *so; int rv; so = ((file_t *)kn->kn_obj)->f_socket; /* * Set kn_data to number of incoming connections, not * counting partial (incomplete) connections. */ if (hint != NOTE_SUBMIT) solock(so); kn->kn_data = so->so_qlen; rv = (kn->kn_data > 0); if (hint != NOTE_SUBMIT) sounlock(so); return rv; } static const struct filterops solisten_filtops = { .f_isfd = 1, .f_attach = NULL, .f_detach = filt_sordetach, .f_event = filt_solisten, }; static const struct filterops soread_filtops = { .f_isfd = 1, .f_attach = NULL, .f_detach = filt_sordetach, .f_event = filt_soread, }; static const struct filterops sowrite_filtops = { .f_isfd = 1, .f_attach = NULL, .f_detach = filt_sowdetach, .f_event = filt_sowrite, }; int soo_kqfilter(struct file *fp, struct knote *kn) { struct socket *so; struct sockbuf *sb; so = ((file_t *)kn->kn_obj)->f_socket; solock(so); switch (kn->kn_filter) { case EVFILT_READ: if (so->so_options & SO_ACCEPTCONN) kn->kn_fop = &solisten_filtops; else kn->kn_fop = &soread_filtops; sb = &so->so_rcv; break; case EVFILT_WRITE: kn->kn_fop = &sowrite_filtops; sb = &so->so_snd; break; default: sounlock(so); return EINVAL; } SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext); sb->sb_flags |= SB_KNOTE; sounlock(so); return 0; } static int sodopoll(struct socket *so, int events) { int revents; revents = 0; if (events & (POLLIN | POLLRDNORM)) if (soreadable(so)) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (sowritable(so)) revents |= events & (POLLOUT | POLLWRNORM); if (events & (POLLPRI | POLLRDBAND)) if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) revents |= events & (POLLPRI | POLLRDBAND); return revents; } int sopoll(struct socket *so, int events) { int revents = 0; #ifndef DIAGNOSTIC /* * Do a quick, unlocked check in expectation that the socket * will be ready for I/O. Don't do this check if DIAGNOSTIC, * as the solocked() assertions will fail. */ if ((revents = sodopoll(so, events)) != 0) return revents; #endif solock(so); if ((revents = sodopoll(so, events)) == 0) { if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { selrecord(curlwp, &so->so_rcv.sb_sel); so->so_rcv.sb_flags |= SB_NOTIFY; } if (events & (POLLOUT | POLLWRNORM)) { selrecord(curlwp, &so->so_snd.sb_sel); so->so_snd.sb_flags |= SB_NOTIFY; } } sounlock(so); return revents; } struct mbuf ** sbsavetimestamp(int opt, struct mbuf **mp) { struct timeval tv; int error; microtime(&tv); MODULE_HOOK_CALL(uipc_socket_50_sbts_hook, (opt, &mp), enosys(), error); if (error == 0) return mp; if (opt & SO_TIMESTAMP) { *mp = sbcreatecontrol(&tv, sizeof(tv), SCM_TIMESTAMP, SOL_SOCKET); if (*mp) mp = &(*mp)->m_next; } return mp; } #include static int sysctl_kern_somaxkva(SYSCTLFN_PROTO); static int sysctl_kern_sbmax(SYSCTLFN_PROTO); /* * sysctl helper routine for kern.somaxkva. ensures that the given * value is not too small. * (XXX should we maybe make sure it's not too large as well?) */ static int sysctl_kern_somaxkva(SYSCTLFN_ARGS) { int error, new_somaxkva; struct sysctlnode node; new_somaxkva = somaxkva; node = *rnode; node.sysctl_data = &new_somaxkva; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return error; if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */ return EINVAL; mutex_enter(&so_pendfree_lock); somaxkva = new_somaxkva; cv_broadcast(&socurkva_cv); mutex_exit(&so_pendfree_lock); return error; } /* * sysctl helper routine for kern.sbmax. Basically just ensures that * any new value is not too small. */ static int sysctl_kern_sbmax(SYSCTLFN_ARGS) { int error, new_sbmax; struct sysctlnode node; new_sbmax = sb_max; node = *rnode; node.sysctl_data = &new_sbmax; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return error; KERNEL_LOCK(1, NULL); error = sb_max_set(new_sbmax); KERNEL_UNLOCK_ONE(NULL); return error; } /* * sysctl helper routine for kern.sooptions. Ensures that only allowed * options can be set. */ static int sysctl_kern_sooptions(SYSCTLFN_ARGS) { int error, new_options; struct sysctlnode node; new_options = sooptions; node = *rnode; node.sysctl_data = &new_options; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return error; if (new_options & ~SO_DEFOPTS) return EINVAL; sooptions = new_options; return 0; } static void sysctl_kern_socket_setup(void) { KASSERT(socket_sysctllog == NULL); sysctl_createv(&socket_sysctllog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "somaxkva", SYSCTL_DESCR("Maximum amount of kernel memory to be " "used for socket buffers"), sysctl_kern_somaxkva, 0, NULL, 0, CTL_KERN, KERN_SOMAXKVA, CTL_EOL); sysctl_createv(&socket_sysctllog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "sbmax", SYSCTL_DESCR("Maximum socket buffer size"), sysctl_kern_sbmax, 0, NULL, 0, CTL_KERN, KERN_SBMAX, CTL_EOL); sysctl_createv(&socket_sysctllog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "sooptions", SYSCTL_DESCR("Default socket options"), sysctl_kern_sooptions, 0, NULL, 0, CTL_KERN, CTL_CREATE, CTL_EOL); }