/* $NetBSD: uipc_socket.c,v 1.101 2004/05/01 02:24:38 matt Exp $ */ /*- * Copyright (c) 2002 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. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation 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 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) 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 */ #include __KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.101 2004/05/01 02:24:38 matt Exp $"); #include "opt_sock_counters.h" #include "opt_sosend_loan.h" #include "opt_mbuftrace.h" #include "opt_somaxkva.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include POOL_INIT(socket_pool, sizeof(struct socket), 0, 0, 0, "sockpl", NULL); MALLOC_DEFINE(M_SOOPTS, "soopts", "socket options"); MALLOC_DEFINE(M_SONAME, "soname", "socket name"); extern int somaxconn; /* patchable (XXX sysctl) */ int somaxconn = SOMAXCONN; #ifdef SOSEND_COUNTERS #include struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "loan big"); struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "copy big"); struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "sosend", "copy small"); 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 */ void soinit(void) { /* Set the initial adjusted socket buffer size. */ if (sb_max_set(sb_max)) panic("bad initial sb_max value: %lu\n", sb_max); } #ifdef SOSEND_NO_LOAN int use_sosend_loan = 0; #else int use_sosend_loan = 1; #endif struct simplelock so_pendfree_slock = SIMPLELOCK_INITIALIZER; struct mbuf *so_pendfree; #ifndef SOMAXKVA #define SOMAXKVA (16 * 1024 * 1024) #endif int somaxkva = SOMAXKVA; int socurkva; int sokvawaiters; #define SOCK_LOAN_THRESH 4096 #define SOCK_LOAN_CHUNK 65536 static size_t sodopendfree(struct socket *); static size_t sodopendfreel(struct socket *); static __inline vsize_t sokvareserve(struct socket *, vsize_t); static __inline void sokvaunreserve(vsize_t); static __inline vsize_t sokvareserve(struct socket *so, vsize_t len) { int s; int error; s = splvm(); simple_lock(&so_pendfree_slock); while (socurkva + len > somaxkva) { size_t freed; /* * try to do pendfree. */ freed = sodopendfreel(so); /* * if some kva was freed, try again. */ if (freed) continue; SOSEND_COUNTER_INCR(&sosend_kvalimit); sokvawaiters++; error = ltsleep(&socurkva, PVM | PCATCH, "sokva", 0, &so_pendfree_slock); sokvawaiters--; if (error) { len = 0; break; } } socurkva += len; simple_unlock(&so_pendfree_slock); splx(s); return len; } static __inline void sokvaunreserve(vsize_t len) { int s; s = splvm(); simple_lock(&so_pendfree_slock); socurkva -= len; if (sokvawaiters) wakeup(&socurkva); simple_unlock(&so_pendfree_slock); splx(s); } /* * sokvaalloc: allocate kva for loan. */ vaddr_t sokvaalloc(vsize_t len, struct socket *so) { vaddr_t lva; /* * reserve kva. */ if (sokvareserve(so, len) == 0) return 0; /* * allocate kva. */ lva = uvm_km_valloc_wait(kernel_map, len); if (lva == 0) { sokvaunreserve(len); return (0); } return lva; } /* * sokvafree: free kva for loan. */ void sokvafree(vaddr_t sva, vsize_t len) { /* * free kva. */ uvm_km_free(kernel_map, sva, len); /* * unreserve kva. */ sokvaunreserve(len); } static void sodoloanfree(struct vm_page **pgs, caddr_t buf, size_t size) { vaddr_t va, sva, eva; vsize_t len; paddr_t pa; int i, npgs; eva = round_page((vaddr_t) buf + size); sva = trunc_page((vaddr_t) buf); len = eva - sva; npgs = len >> PAGE_SHIFT; if (__predict_false(pgs == NULL)) { pgs = alloca(npgs * sizeof(*pgs)); for (i = 0, va = sva; va < eva; i++, va += PAGE_SIZE) { if (pmap_extract(pmap_kernel(), va, &pa) == FALSE) panic("sodoloanfree: va 0x%lx not mapped", va); pgs[i] = PHYS_TO_VM_PAGE(pa); } } pmap_kremove(sva, len); pmap_update(pmap_kernel()); uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE); sokvafree(sva, len); } static size_t sodopendfree(struct socket *so) { int s; size_t rv; s = splvm(); simple_lock(&so_pendfree_slock); rv = sodopendfreel(so); simple_unlock(&so_pendfree_slock); splx(s); return rv; } /* * sodopendfreel: free mbufs on "pendfree" list. * unlock and relock so_pendfree_slock when freeing mbufs. * * => called with so_pendfree_slock held. * => called at splvm. */ static size_t sodopendfreel(struct socket *so) { size_t rv = 0; LOCK_ASSERT(simple_lock_held(&so_pendfree_slock)); for (;;) { struct mbuf *m; struct mbuf *next; m = so_pendfree; if (m == NULL) break; so_pendfree = NULL; simple_unlock(&so_pendfree_slock); /* XXX splx */ for (; m != NULL; m = next) { next = m->m_next; rv += m->m_ext.ext_size; sodoloanfree((m->m_flags & M_EXT_PAGES) ? m->m_ext.ext_pgs : NULL, m->m_ext.ext_buf, m->m_ext.ext_size); pool_cache_put(&mbpool_cache, m); } /* XXX splvm */ simple_lock(&so_pendfree_slock); } return (rv); } void soloanfree(struct mbuf *m, caddr_t buf, size_t size, void *arg) { int s; if (m == NULL) { /* * called from MEXTREMOVE. */ sodoloanfree(NULL, buf, size); return; } /* * postpone freeing mbuf. * * we can't do it in interrupt context * because we need to put kva back to kernel_map. */ s = splvm(); simple_lock(&so_pendfree_slock); m->m_next = so_pendfree; so_pendfree = m; if (sokvawaiters) wakeup(&socurkva); simple_unlock(&so_pendfree_slock); splx(s); } 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, va; int npgs, i, error; if (uio->uio_segflg != UIO_USERSPACE) 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; /* XXX KDASSERT */ KASSERT(npgs <= M_EXT_MAXPAGES); lva = sokvaalloc(len, so); if (lva == 0) return 0; error = uvm_loan(&uio->uio_procp->p_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); pmap_update(pmap_kernel()); lva += (vaddr_t) iov->iov_base & PAGE_MASK; MEXTADD(m, (caddr_t) 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 = (caddr_t) 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); } /* * 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. */ /*ARGSUSED*/ int socreate(int dom, struct socket **aso, int type, int proto) { struct proc *p; const struct protosw *prp; struct socket *so; int error, s; p = curproc; /* XXX */ if (proto) prp = pffindproto(dom, proto, type); else prp = pffindtype(dom, type); if (prp == 0 || prp->pr_usrreq == 0) return (EPROTONOSUPPORT); if (prp->pr_type != type) return (EPROTOTYPE); s = splsoftnet(); so = pool_get(&socket_pool, PR_WAITOK); memset((caddr_t)so, 0, sizeof(*so)); TAILQ_INIT(&so->so_q0); TAILQ_INIT(&so->so_q); so->so_type = type; so->so_proto = prp; so->so_send = sosend; so->so_receive = soreceive; #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 if (p != 0) so->so_uid = p->p_ucred->cr_uid; else so->so_uid = UID_MAX; error = (*prp->pr_usrreq)(so, PRU_ATTACH, (struct mbuf *)0, (struct mbuf *)(long)proto, (struct mbuf *)0, p); if (error) { so->so_state |= SS_NOFDREF; sofree(so); splx(s); return (error); } splx(s); *aso = so; return (0); } int sobind(struct socket *so, struct mbuf *nam, struct proc *p) { int s, error; s = splsoftnet(); error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, (struct mbuf *)0, nam, (struct mbuf *)0, p); splx(s); return (error); } int solisten(struct socket *so, int backlog) { int s, error; s = splsoftnet(); error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); if (error) { splx(s); return (error); } if (TAILQ_EMPTY(&so->so_q)) so->so_options |= SO_ACCEPTCONN; if (backlog < 0) backlog = 0; so->so_qlimit = min(backlog, somaxconn); splx(s); return (0); } void sofree(struct socket *so) { if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) 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)) return; } if (so->so_rcv.sb_hiwat) (void)chgsbsize(so->so_uid, &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); if (so->so_snd.sb_hiwat) (void)chgsbsize(so->so_uid, &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); sbrelease(&so->so_snd, so); sorflush(so); pool_put(&socket_pool, so); } /* * 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 s, error; error = 0; s = splsoftnet(); /* conservative */ if (so->so_options & SO_ACCEPTCONN) { while ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) { (void) soqremque(so2, 0); (void) soabort(so2); } while ((so2 = TAILQ_FIRST(&so->so_q)) != 0) { (void) soqremque(so2, 1); (void) soabort(so2); } } if (so->so_pcb == 0) 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) && (so->so_state & SS_NBIO)) goto drop; while (so->so_state & SS_ISCONNECTED) { error = tsleep((caddr_t)&so->so_timeo, PSOCK | PCATCH, netcls, so->so_linger * hz); if (error) break; } } } drop: if (so->so_pcb) { int error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); if (error == 0) error = error2; } discard: if (so->so_state & SS_NOFDREF) panic("soclose: NOFDREF"); so->so_state |= SS_NOFDREF; sofree(so); splx(s); return (error); } /* * Must be called at splsoftnet... */ int soabort(struct socket *so) { return (*so->so_proto->pr_usrreq)(so, PRU_ABORT, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); } int soaccept(struct socket *so, struct mbuf *nam) { int s, error; error = 0; s = splsoftnet(); if ((so->so_state & SS_NOFDREF) == 0) panic("soaccept: !NOFDREF"); 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_usrreq)(so, PRU_ACCEPT, (struct mbuf *)0, nam, (struct mbuf *)0, (struct proc *)0); else error = ECONNABORTED; splx(s); return (error); } int soconnect(struct socket *so, struct mbuf *nam) { struct proc *p; int s, error; p = curproc; /* XXX */ if (so->so_options & SO_ACCEPTCONN) return (EOPNOTSUPP); s = splsoftnet(); /* * 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 error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT, (struct mbuf *)0, nam, (struct mbuf *)0, p); splx(s); return (error); } int soconnect2(struct socket *so1, struct socket *so2) { int s, error; s = splsoftnet(); error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2, (struct mbuf *)0, (struct mbuf *)so2, (struct mbuf *)0, (struct proc *)0); splx(s); return (error); } int sodisconnect(struct socket *so) { int s, error; s = splsoftnet(); if ((so->so_state & SS_ISCONNECTED) == 0) { error = ENOTCONN; goto bad; } if (so->so_state & SS_ISDISCONNECTING) { error = EALREADY; goto bad; } error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); bad: splx(s); sodopendfree(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 mbuf *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags) { struct proc *p; struct mbuf **mp, *m; long space, len, resid, clen, mlen; int error, s, dontroute, atomic; sodopendfree(so); p = curproc; /* XXX */ clen = 0; 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); p->p_stats->p_ru.ru_msgsnd++; if (control) clen = control->m_len; #define snderr(errno) { error = errno; splx(s); goto release; } restart: if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0) goto out; do { s = splsoftnet(); if (so->so_state & SS_CANTSENDMORE) snderr(EPIPE); if (so->so_error) { error = so->so_error; so->so_error = 0; splx(s); goto release; } if ((so->so_state & SS_ISCONNECTED) == 0) { if (so->so_proto->pr_flags & PR_CONNREQUIRED) { if ((so->so_state & SS_ISCONFIRMING) == 0 && !(resid == 0 && clen != 0)) snderr(ENOTCONN); } else if (addr == 0) snderr(EDESTADDRREQ); } 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) snderr(EMSGSIZE); if (space < resid + clen && (atomic || space < so->so_snd.sb_lowat || space < clen)) { if (so->so_state & SS_NBIO) snderr(EWOULDBLOCK); sbunlock(&so->so_snd); error = sbwait(&so->so_snd); splx(s); if (error) goto out; goto restart; } splx(s); 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 { if (top == 0) { m = m_gethdr(M_WAIT, MT_DATA); mlen = MHLEN; m->m_pkthdr.len = 0; m->m_pkthdr.rcvif = (struct ifnet *)0; } else { m = m_get(M_WAIT, MT_DATA); mlen = MLEN; } MCLAIM(m, so->so_snd.sb_mowner); if (use_sosend_loan && 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_WAIT); 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) MH_ALIGN(m, len); } error = uiomove(mtod(m, caddr_t), (int)len, uio); have_data: resid = uio->uio_resid; m->m_len = len; *mp = m; top->m_pkthdr.len += len; if (error) goto release; mp = &m->m_next; if (resid <= 0) { if (flags & MSG_EOR) top->m_flags |= M_EOR; break; } } while (space > 0 && atomic); s = splsoftnet(); if (so->so_state & SS_CANTSENDMORE) snderr(EPIPE); if (dontroute) so->so_options |= SO_DONTROUTE; if (resid > 0) so->so_state |= SS_MORETOCOME; error = (*so->so_proto->pr_usrreq)(so, (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND, top, addr, control, p); if (dontroute) so->so_options &= ~SO_DONTROUTE; if (resid > 0) so->so_state &= ~SS_MORETOCOME; splx(s); clen = 0; control = 0; top = 0; mp = ⊤ if (error) goto release; } while (resid && space > 0); } while (resid); release: sbunlock(&so->so_snd); out: if (top) m_freem(top); if (control) m_freem(control); return (error); } /* * 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 mbuf *m, **mp; int flags, len, error, s, offset, moff, type, orig_resid; const struct protosw *pr; struct mbuf *nextrecord; int mbuf_removed = 0; pr = so->so_proto; mp = mp0; type = 0; orig_resid = uio->uio_resid; if (paddr) *paddr = 0; if (controlp) *controlp = 0; if (flagsp) flags = *flagsp &~ MSG_EOR; else flags = 0; if ((flags & MSG_DONTWAIT) == 0) sodopendfree(so); if (flags & MSG_OOB) { m = m_get(M_WAIT, MT_DATA); error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m, (struct mbuf *)(long)(flags & MSG_PEEK), (struct mbuf *)0, (struct proc *)0); if (error) goto bad; do { error = uiomove(mtod(m, caddr_t), (int) min(uio->uio_resid, m->m_len), uio); m = m_free(m); } while (uio->uio_resid && error == 0 && m); bad: if (m) m_freem(m); return (error); } if (mp) *mp = (struct mbuf *)0; if (so->so_state & SS_ISCONFIRMING && uio->uio_resid) (*pr->pr_usrreq)(so, PRU_RCVD, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); restart: if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) return (error); s = splsoftnet(); 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 == 0 || (((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 == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) { #ifdef DIAGNOSTIC if (m == 0 && so->so_rcv.sb_cc) panic("receive 1"); #endif if (so->so_error) { if (m) goto dontblock; error = so->so_error; if ((flags & MSG_PEEK) == 0) so->so_error = 0; goto release; } if (so->so_state & SS_CANTRCVMORE) { if (m) goto dontblock; else goto release; } for (; m; 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)) { error = EWOULDBLOCK; goto release; } SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1"); sbunlock(&so->so_rcv); error = sbwait(&so->so_rcv); splx(s); if (error) return (error); goto restart; } dontblock: /* * On entry here, m points to the first record of the socket buffer. * While we process the initial mbufs containing address and control * info, we save a copy of m->m_nextpkt into nextrecord. */ #ifdef notyet /* XXXX */ if (uio->uio_procp) uio->uio_procp->p_stats->p_ru.ru_msgrcv++; #endif 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) { #ifdef DIAGNOSTIC if (m->m_type != MT_SONAME) panic("receive 1a"); #endif orig_resid = 0; if (flags & MSG_PEEK) { if (paddr) *paddr = m_copy(m, 0, m->m_len); m = m->m_next; } else { sbfree(&so->so_rcv, m); mbuf_removed = 1; if (paddr) { *paddr = m; so->so_rcv.sb_mb = m->m_next; m->m_next = 0; m = so->so_rcv.sb_mb; } else { MFREE(m, so->so_rcv.sb_mb); m = so->so_rcv.sb_mb; } } } while (m && m->m_type == MT_CONTROL && error == 0) { if (flags & MSG_PEEK) { if (controlp) *controlp = m_copy(m, 0, m->m_len); m = m->m_next; } else { sbfree(&so->so_rcv, m); mbuf_removed = 1; if (controlp) { if (pr->pr_domain->dom_externalize && mtod(m, struct cmsghdr *)->cmsg_type == SCM_RIGHTS) error = (*pr->pr_domain->dom_externalize)(m); *controlp = m; so->so_rcv.sb_mb = m->m_next; m->m_next = 0; m = so->so_rcv.sb_mb; } else { MFREE(m, so->so_rcv.sb_mb); m = so->so_rcv.sb_mb; } } if (controlp) { orig_resid = 0; controlp = &(*controlp)->m_next; } } /* * If m is non-NULL, we have some data to read. From now on, * make sure to keep sb_lastrecord consistent when working on * the last packet on the chain (nextrecord == NULL) and we * change m->m_nextpkt. */ if (m) { if ((flags & MSG_PEEK) == 0) { m->m_nextpkt = nextrecord; /* * If nextrecord == NULL (this is a single chain), * then sb_lastrecord may not be valid here if m * was changed earlier. */ if (nextrecord == NULL) { KASSERT(so->so_rcv.sb_mb == m); so->so_rcv.sb_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 == m); so->so_rcv.sb_mb = nextrecord; SB_EMPTY_FIXUP(&so->so_rcv); } } SBLASTRECORDCHK(&so->so_rcv, "soreceive 2"); SBLASTMBUFCHK(&so->so_rcv, "soreceive 2"); moff = 0; offset = 0; while (m && uio->uio_resid > 0 && error == 0) { if (m->m_type == MT_OOBDATA) { if (type != MT_OOBDATA) break; } else if (type == MT_OOBDATA) break; #ifdef DIAGNOSTIC else if (m->m_type != MT_DATA && m->m_type != MT_HEADER) panic("receive 3"); #endif so->so_state &= ~SS_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 == 0) { SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove"); SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove"); splx(s); error = uiomove(mtod(m, caddr_t) + moff, (int)len, uio); s = splsoftnet(); if (error) { /* * 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 && (pr->pr_flags & PR_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; 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 = (struct mbuf *)0; } else { MFREE(m, so->so_rcv.sb_mb); m = so->so_rcv.sb_mb; } /* * 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) *mp = m_copym(m, 0, len, M_WAIT); 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 == 0 && uio->uio_resid > 0 && !sosendallatonce(so) && !nextrecord) { if (so->so_error || 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_usrreq)(so, PRU_RCVD, (struct mbuf *)0, (struct mbuf *)(long)flags, (struct mbuf *)0, (struct proc *)0); SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2"); SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2"); error = sbwait(&so->so_rcv); if (error) { sbunlock(&so->so_rcv); splx(s); return (0); } if ((m = so->so_rcv.sb_mb) != NULL) nextrecord = m->m_nextpkt; } } if (m && pr->pr_flags & PR_ATOMIC) { flags |= MSG_TRUNC; if ((flags & MSG_PEEK) == 0) (void) sbdroprecord(&so->so_rcv); } if ((flags & MSG_PEEK) == 0) { if (m == 0) { /* * 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_usrreq)(so, PRU_RCVD, (struct mbuf *)0, (struct mbuf *)(long)flags, (struct mbuf *)0, (struct proc *)0); } if (orig_resid == uio->uio_resid && orig_resid && (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) { sbunlock(&so->so_rcv); splx(s); goto restart; } if (flagsp) *flagsp |= flags; release: sbunlock(&so->so_rcv); splx(s); return (error); } int soshutdown(struct socket *so, int how) { const struct protosw *pr; 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); if (how == SHUT_WR || how == SHUT_RDWR) return (*pr->pr_usrreq)(so, PRU_SHUTDOWN, (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0, (struct proc *)0); return (0); } void sorflush(struct socket *so) { struct sockbuf *sb, asb; const struct protosw *pr; int s; sb = &so->so_rcv; pr = so->so_proto; sb->sb_flags |= SB_NOINTR; (void) sblock(sb, M_WAITOK); s = splnet(); socantrcvmore(so); 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)); splx(s); if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) (*pr->pr_domain->dom_dispose)(asb.sb_mb); sbrelease(&asb, so); } int sosetopt(struct socket *so, int level, int optname, struct mbuf *m0) { int error; struct mbuf *m; error = 0; m = m0; if (level != SOL_SOCKET) { if (so->so_proto && so->so_proto->pr_ctloutput) return ((*so->so_proto->pr_ctloutput) (PRCO_SETOPT, so, level, optname, &m0)); error = ENOPROTOOPT; } else { switch (optname) { case SO_LINGER: if (m == NULL || m->m_len != sizeof(struct linger)) { error = EINVAL; goto bad; } so->so_linger = mtod(m, struct linger *)->l_linger; /* fall thru... */ 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: if (m == NULL || m->m_len < sizeof(int)) { error = EINVAL; goto bad; } if (*mtod(m, int *)) so->so_options |= optname; else so->so_options &= ~optname; break; case SO_SNDBUF: case SO_RCVBUF: case SO_SNDLOWAT: case SO_RCVLOWAT: { int optval; if (m == NULL || m->m_len < sizeof(int)) { error = EINVAL; goto bad; } /* * Values < 1 make no sense for any of these * options, so disallow them. */ optval = *mtod(m, int *); if (optval < 1) { error = EINVAL; goto bad; } switch (optname) { case SO_SNDBUF: case SO_RCVBUF: if (sbreserve(optname == SO_SNDBUF ? &so->so_snd : &so->so_rcv, (u_long) optval, so) == 0) { error = ENOBUFS; goto bad; } break; /* * Make sure the low-water is never greater than * the high-water. */ case SO_SNDLOWAT: so->so_snd.sb_lowat = (optval > so->so_snd.sb_hiwat) ? so->so_snd.sb_hiwat : optval; break; case SO_RCVLOWAT: so->so_rcv.sb_lowat = (optval > so->so_rcv.sb_hiwat) ? so->so_rcv.sb_hiwat : optval; break; } break; } case SO_SNDTIMEO: case SO_RCVTIMEO: { struct timeval *tv; short val; if (m == NULL || m->m_len < sizeof(*tv)) { error = EINVAL; goto bad; } tv = mtod(m, struct timeval *); if (tv->tv_sec > (SHRT_MAX - tv->tv_usec / tick) / hz) { error = EDOM; goto bad; } val = tv->tv_sec * hz + tv->tv_usec / tick; if (val == 0 && tv->tv_usec != 0) val = 1; switch (optname) { case SO_SNDTIMEO: so->so_snd.sb_timeo = val; break; case SO_RCVTIMEO: so->so_rcv.sb_timeo = val; break; } break; } default: error = ENOPROTOOPT; break; } if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) { (void) ((*so->so_proto->pr_ctloutput) (PRCO_SETOPT, so, level, optname, &m0)); m = NULL; /* freed by protocol */ } } bad: if (m) (void) m_free(m); return (error); } int sogetopt(struct socket *so, int level, int optname, struct mbuf **mp) { struct mbuf *m; if (level != SOL_SOCKET) { if (so->so_proto && so->so_proto->pr_ctloutput) { return ((*so->so_proto->pr_ctloutput) (PRCO_GETOPT, so, level, optname, mp)); } else return (ENOPROTOOPT); } else { m = m_get(M_WAIT, MT_SOOPTS); m->m_len = sizeof(int); switch (optname) { case SO_LINGER: m->m_len = sizeof(struct linger); mtod(m, struct linger *)->l_onoff = so->so_options & SO_LINGER; mtod(m, struct linger *)->l_linger = so->so_linger; 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: *mtod(m, int *) = so->so_options & optname; break; case SO_TYPE: *mtod(m, int *) = so->so_type; break; case SO_ERROR: *mtod(m, int *) = so->so_error; so->so_error = 0; break; case SO_SNDBUF: *mtod(m, int *) = so->so_snd.sb_hiwat; break; case SO_RCVBUF: *mtod(m, int *) = so->so_rcv.sb_hiwat; break; case SO_SNDLOWAT: *mtod(m, int *) = so->so_snd.sb_lowat; break; case SO_RCVLOWAT: *mtod(m, int *) = so->so_rcv.sb_lowat; break; case SO_SNDTIMEO: case SO_RCVTIMEO: { int val = (optname == SO_SNDTIMEO ? so->so_snd.sb_timeo : so->so_rcv.sb_timeo); m->m_len = sizeof(struct timeval); mtod(m, struct timeval *)->tv_sec = val / hz; mtod(m, struct timeval *)->tv_usec = (val % hz) * tick; break; } default: (void)m_free(m); return (ENOPROTOOPT); } *mp = m; return (0); } } void sohasoutofband(struct socket *so) { fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so); selwakeup(&so->so_rcv.sb_sel); } static void filt_sordetach(struct knote *kn) { struct socket *so; so = (struct socket *)kn->kn_fp->f_data; 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; } /*ARGSUSED*/ static int filt_soread(struct knote *kn, long hint) { struct socket *so; so = (struct socket *)kn->kn_fp->f_data; 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; return (1); } if (so->so_error) /* temporary udp error */ return (1); if (kn->kn_sfflags & NOTE_LOWAT) return (kn->kn_data >= kn->kn_sdata); return (kn->kn_data >= so->so_rcv.sb_lowat); } static void filt_sowdetach(struct knote *kn) { struct socket *so; so = (struct socket *)kn->kn_fp->f_data; 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; } /*ARGSUSED*/ static int filt_sowrite(struct knote *kn, long hint) { struct socket *so; so = (struct socket *)kn->kn_fp->f_data; kn->kn_data = sbspace(&so->so_snd); if (so->so_state & SS_CANTSENDMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } if (so->so_error) /* temporary udp error */ return (1); if (((so->so_state & SS_ISCONNECTED) == 0) && (so->so_proto->pr_flags & PR_CONNREQUIRED)) return (0); if (kn->kn_sfflags & NOTE_LOWAT) return (kn->kn_data >= kn->kn_sdata); return (kn->kn_data >= so->so_snd.sb_lowat); } /*ARGSUSED*/ static int filt_solisten(struct knote *kn, long hint) { struct socket *so; so = (struct socket *)kn->kn_fp->f_data; /* * Set kn_data to number of incoming connections, not * counting partial (incomplete) connections. */ kn->kn_data = so->so_qlen; return (kn->kn_data > 0); } static const struct filterops solisten_filtops = { 1, NULL, filt_sordetach, filt_solisten }; static const struct filterops soread_filtops = { 1, NULL, filt_sordetach, filt_soread }; static const struct filterops sowrite_filtops = { 1, NULL, filt_sowdetach, filt_sowrite }; int soo_kqfilter(struct file *fp, struct knote *kn) { struct socket *so; struct sockbuf *sb; so = (struct socket *)kn->kn_fp->f_data; 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: return (1); } SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext); sb->sb_flags |= SB_KNOTE; return (0); } #include static int sysctl_kern_somaxkva(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; int s; 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); s = splvm(); simple_lock(&so_pendfree_slock); somaxkva = new_somaxkva; wakeup(&socurkva); simple_unlock(&so_pendfree_slock); splx(s); return (error); } SYSCTL_SETUP(sysctl_kern_somaxkva_setup, "sysctl kern.somaxkva setup") { sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "kern", NULL, NULL, 0, NULL, 0, CTL_KERN, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "somaxkva", NULL, sysctl_kern_somaxkva, 0, NULL, 0, CTL_KERN, KERN_SOMAXKVA, CTL_EOL); }