diff --git a/sys/kern/kern_sendfile.c b/sys/kern/kern_sendfile.c index 520b7c9c62d0..ac1072ca2406 100644 --- a/sys/kern/kern_sendfile.c +++ b/sys/kern/kern_sendfile.c @@ -1,1367 +1,1371 @@ /*- * Copyright (c) 2013-2015 Gleb Smirnoff * Copyright (c) 1998, David Greenman. 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. */ #include __FBSDID("$FreeBSD$"); #include "opt_kern_tls.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_SENDFILE, "sendfile", "sendfile dynamic memory"); #define EXT_FLAG_SYNC EXT_FLAG_VENDOR1 #define EXT_FLAG_NOCACHE EXT_FLAG_VENDOR2 #define EXT_FLAG_CACHE_LAST EXT_FLAG_VENDOR3 /* * Structure describing a single sendfile(2) I/O, which may consist of * several underlying pager I/Os. * * The syscall context allocates the structure and initializes 'nios' * to 1. As sendfile_swapin() runs through pages and starts asynchronous * paging operations, it increments 'nios'. * * Every I/O completion calls sendfile_iodone(), which decrements the 'nios', * and the syscall also calls sendfile_iodone() after allocating all mbufs, * linking them and sending to socket. Whoever reaches zero 'nios' is * responsible to * call pru_ready on the socket, to notify it of readyness * of the data. */ struct sf_io { volatile u_int nios; u_int error; int npages; struct socket *so; struct mbuf *m; vm_object_t obj; vm_pindex_t pindex0; #ifdef KERN_TLS struct ktls_session *tls; #endif vm_page_t pa[]; }; /* * Structure used to track requests with SF_SYNC flag. */ struct sendfile_sync { struct mtx mtx; struct cv cv; unsigned count; bool waiting; }; static void sendfile_sync_destroy(struct sendfile_sync *sfs) { KASSERT(sfs->count == 0, ("sendfile sync %p still busy", sfs)); cv_destroy(&sfs->cv); mtx_destroy(&sfs->mtx); free(sfs, M_SENDFILE); } static void sendfile_sync_signal(struct sendfile_sync *sfs) { mtx_lock(&sfs->mtx); KASSERT(sfs->count > 0, ("sendfile sync %p not busy", sfs)); if (--sfs->count == 0) { if (!sfs->waiting) { /* The sendfile() waiter was interrupted by a signal. */ sendfile_sync_destroy(sfs); return; } else { cv_signal(&sfs->cv); } } mtx_unlock(&sfs->mtx); } counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)]; static void sfstat_init(const void *unused) { COUNTER_ARRAY_ALLOC(sfstat, sizeof(struct sfstat) / sizeof(uint64_t), M_WAITOK); } SYSINIT(sfstat, SI_SUB_MBUF, SI_ORDER_FIRST, sfstat_init, NULL); static int sfstat_sysctl(SYSCTL_HANDLER_ARGS) { struct sfstat s; COUNTER_ARRAY_COPY(sfstat, &s, sizeof(s) / sizeof(uint64_t)); if (req->newptr) COUNTER_ARRAY_ZERO(sfstat, sizeof(s) / sizeof(uint64_t)); return (SYSCTL_OUT(req, &s, sizeof(s))); } SYSCTL_PROC(_kern_ipc, OID_AUTO, sfstat, CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_NEEDGIANT, NULL, 0, sfstat_sysctl, "I", "sendfile statistics"); static void sendfile_free_mext(struct mbuf *m) { struct sf_buf *sf; vm_page_t pg; int flags; KASSERT(m->m_flags & M_EXT && m->m_ext.ext_type == EXT_SFBUF, ("%s: m %p !M_EXT or !EXT_SFBUF", __func__, m)); sf = m->m_ext.ext_arg1; pg = sf_buf_page(sf); flags = (m->m_ext.ext_flags & EXT_FLAG_NOCACHE) != 0 ? VPR_TRYFREE : 0; sf_buf_free(sf); vm_page_release(pg, flags); if (m->m_ext.ext_flags & EXT_FLAG_SYNC) { struct sendfile_sync *sfs = m->m_ext.ext_arg2; sendfile_sync_signal(sfs); } } static void sendfile_free_mext_pg(struct mbuf *m) { vm_page_t pg; int flags, i; bool cache_last; M_ASSERTEXTPG(m); cache_last = m->m_ext.ext_flags & EXT_FLAG_CACHE_LAST; flags = (m->m_ext.ext_flags & EXT_FLAG_NOCACHE) != 0 ? VPR_TRYFREE : 0; for (i = 0; i < m->m_epg_npgs; i++) { if (cache_last && i == m->m_epg_npgs - 1) flags = 0; pg = PHYS_TO_VM_PAGE(m->m_epg_pa[i]); vm_page_release(pg, flags); } if (m->m_ext.ext_flags & EXT_FLAG_SYNC) { struct sendfile_sync *sfs = m->m_ext.ext_arg1; sendfile_sync_signal(sfs); } } /* * Helper function to calculate how much data to put into page i of n. * Only first and last pages are special. */ static inline off_t xfsize(int i, int n, off_t off, off_t len) { if (i == 0) return (omin(PAGE_SIZE - (off & PAGE_MASK), len)); if (i == n - 1 && ((off + len) & PAGE_MASK) > 0) return ((off + len) & PAGE_MASK); return (PAGE_SIZE); } /* * Helper function to get offset within object for i page. */ static inline vm_ooffset_t vmoff(int i, off_t off) { if (i == 0) return ((vm_ooffset_t)off); return (trunc_page(off + i * PAGE_SIZE)); } /* * Helper function used when allocation of a page or sf_buf failed. * Pretend as if we don't have enough space, subtract xfsize() of * all pages that failed. */ static inline void fixspace(int old, int new, off_t off, int *space) { KASSERT(old > new, ("%s: old %d new %d", __func__, old, new)); /* Subtract last one. */ *space -= xfsize(old - 1, old, off, *space); old--; if (new == old) /* There was only one page. */ return; /* Subtract first one. */ if (new == 0) { *space -= xfsize(0, old, off, *space); new++; } /* Rest of pages are full sized. */ *space -= (old - new) * PAGE_SIZE; KASSERT(*space >= 0, ("%s: space went backwards", __func__)); } /* * Wait for all in-flight ios to complete, we must not unwire pages * under them. */ static void sendfile_iowait(struct sf_io *sfio, const char *wmesg) { while (atomic_load_int(&sfio->nios) != 1) pause(wmesg, 1); } /* * I/O completion callback. */ static void sendfile_iodone(void *arg, vm_page_t *pa, int count, int error) { struct sf_io *sfio = arg; struct socket *so; int i; if (error != 0) sfio->error = error; /* * Restore the valid page pointers. They are already * unbusied, but still wired. * * XXXKIB since pages are only wired, and we do not * own the object lock, other users might have * invalidated them in meantime. Similarly, after we * unbusied the swapped-in pages, they can become * invalid under us. */ MPASS(count == 0 || pa[0] != bogus_page); for (i = 0; i < count; i++) { if (pa[i] == bogus_page) { sfio->pa[(pa[0]->pindex - sfio->pindex0) + i] = pa[i] = vm_page_relookup(sfio->obj, pa[0]->pindex + i); KASSERT(pa[i] != NULL, ("%s: page %p[%d] disappeared", __func__, pa, i)); } else { vm_page_xunbusy_unchecked(pa[i]); } } if (!refcount_release(&sfio->nios)) return; #ifdef INVARIANTS for (i = 1; i < sfio->npages; i++) { if (sfio->pa[i] == NULL) break; KASSERT(vm_page_wired(sfio->pa[i]), ("sfio %p page %d %p not wired", sfio, i, sfio->pa[i])); if (i == 0) continue; KASSERT(sfio->pa[0]->object == sfio->pa[i]->object, ("sfio %p page %d %p wrong owner %p %p", sfio, i, sfio->pa[i], sfio->pa[0]->object, sfio->pa[i]->object)); KASSERT(sfio->pa[0]->pindex + i == sfio->pa[i]->pindex, ("sfio %p page %d %p wrong index %jx %jx", sfio, i, sfio->pa[i], (uintmax_t)sfio->pa[0]->pindex, (uintmax_t)sfio->pa[i]->pindex)); } #endif vm_object_pip_wakeup(sfio->obj); if (sfio->m == NULL) { /* * Either I/O operation failed, or we failed to allocate * buffers, or we bailed out on first busy page, or we * succeeded filling the request without any I/Os. Anyway, * pru_send hadn't been executed - nothing had been sent * to the socket yet. */ MPASS((curthread->td_pflags & TDP_KTHREAD) == 0); free(sfio, M_SENDFILE); return; } #if defined(KERN_TLS) && defined(INVARIANTS) if ((sfio->m->m_flags & M_EXTPG) != 0) KASSERT(sfio->tls == sfio->m->m_epg_tls, ("TLS session mismatch")); else KASSERT(sfio->tls == NULL, ("non-ext_pgs mbuf with TLS session")); #endif so = sfio->so; CURVNET_SET(so->so_vnet); if (__predict_false(sfio->error)) { /* * I/O operation failed. The state of data in the socket * is now inconsistent, and all what we can do is to tear * it down. Protocol abort method would tear down protocol * state, free all ready mbufs and detach not ready ones. * We will free the mbufs corresponding to this I/O manually. * * The socket would be marked with EIO and made available * for read, so that application receives EIO on next * syscall and eventually closes the socket. */ so->so_proto->pr_usrreqs->pru_abort(so); so->so_error = EIO; mb_free_notready(sfio->m, sfio->npages); #ifdef KERN_TLS } else if (sfio->tls != NULL && sfio->tls->mode == TCP_TLS_MODE_SW) { /* * I/O operation is complete, but we still need to * encrypt. We cannot do this in the interrupt thread * of the disk controller, so forward the mbufs to a * different thread. * * Donate the socket reference from sfio to rather * than explicitly invoking soref(). */ ktls_enqueue(sfio->m, so, sfio->npages); goto out_with_ref; #endif } else (void)(so->so_proto->pr_usrreqs->pru_ready)(so, sfio->m, sfio->npages); SOCK_LOCK(so); sorele(so); #ifdef KERN_TLS out_with_ref: #endif CURVNET_RESTORE(); free(sfio, M_SENDFILE); } /* * Iterate through pages vector and request paging for non-valid pages. */ static int sendfile_swapin(vm_object_t obj, struct sf_io *sfio, int *nios, off_t off, off_t len, int rhpages, int flags) { vm_page_t *pa; int a, count, count1, grabbed, i, j, npages, rv; pa = sfio->pa; npages = sfio->npages; *nios = 0; flags = (flags & SF_NODISKIO) ? VM_ALLOC_NOWAIT : 0; sfio->pindex0 = OFF_TO_IDX(off); /* * First grab all the pages and wire them. Note that we grab * only required pages. Readahead pages are dealt with later. */ grabbed = vm_page_grab_pages_unlocked(obj, OFF_TO_IDX(off), VM_ALLOC_NORMAL | VM_ALLOC_WIRED | flags, pa, npages); if (grabbed < npages) { for (int i = grabbed; i < npages; i++) pa[i] = NULL; npages = grabbed; rhpages = 0; } for (i = 0; i < npages;) { /* Skip valid pages. */ if (vm_page_is_valid(pa[i], vmoff(i, off) & PAGE_MASK, xfsize(i, npages, off, len))) { vm_page_xunbusy(pa[i]); SFSTAT_INC(sf_pages_valid); i++; continue; } /* * Next page is invalid. Check if it belongs to pager. It * may not be there, which is a regular situation for shmem * pager. For vnode pager this happens only in case of * a sparse file. * * Important feature of vm_pager_has_page() is the hint * stored in 'a', about how many pages we can pagein after * this page in a single I/O. */ VM_OBJECT_RLOCK(obj); if (!vm_pager_has_page(obj, OFF_TO_IDX(vmoff(i, off)), NULL, &a)) { VM_OBJECT_RUNLOCK(obj); pmap_zero_page(pa[i]); vm_page_valid(pa[i]); MPASS(pa[i]->dirty == 0); vm_page_xunbusy(pa[i]); i++; continue; } VM_OBJECT_RUNLOCK(obj); /* * We want to pagein as many pages as possible, limited only * by the 'a' hint and actual request. */ count = min(a + 1, npages - i); /* * We should not pagein into a valid page because * there might be still unfinished write tracked by * e.g. a buffer, thus we substitute any valid pages * with the bogus one. * * We must not leave around xbusy pages which are not * part of the run passed to vm_pager_getpages(), * otherwise pager might deadlock waiting for the busy * status of the page, e.g. if it constitues the * buffer needed to validate other page. * * First trim the end of the run consisting of the * valid pages, then replace the rest of the valid * with bogus. */ count1 = count; for (j = i + count - 1; j > i; j--) { if (vm_page_is_valid(pa[j], vmoff(j, off) & PAGE_MASK, xfsize(j, npages, off, len))) { vm_page_xunbusy(pa[j]); SFSTAT_INC(sf_pages_valid); count--; } else { break; } } /* * The last page in the run pa[i + count - 1] is * guaranteed to be invalid by the trim above, so it * is not replaced with bogus, thus -1 in the loop end * condition. */ MPASS(pa[i + count - 1]->valid != VM_PAGE_BITS_ALL); for (j = i + 1; j < i + count - 1; j++) { if (vm_page_is_valid(pa[j], vmoff(j, off) & PAGE_MASK, xfsize(j, npages, off, len))) { vm_page_xunbusy(pa[j]); SFSTAT_INC(sf_pages_valid); SFSTAT_INC(sf_pages_bogus); pa[j] = bogus_page; } } refcount_acquire(&sfio->nios); rv = vm_pager_get_pages_async(obj, pa + i, count, NULL, i + count == npages ? &rhpages : NULL, &sendfile_iodone, sfio); if (__predict_false(rv != VM_PAGER_OK)) { sendfile_iowait(sfio, "sferrio"); /* * Do remaining pages recovery before returning EIO. * Pages from 0 to npages are wired. * Pages from (i + count1) to npages are busied. */ for (j = 0; j < npages; j++) { if (j >= i + count1) vm_page_xunbusy(pa[j]); KASSERT(pa[j] != NULL && pa[j] != bogus_page, ("%s: page %p[%d] I/O recovery failure", __func__, pa, j)); vm_page_unwire(pa[j], PQ_INACTIVE); pa[j] = NULL; } return (EIO); } SFSTAT_INC(sf_iocnt); SFSTAT_ADD(sf_pages_read, count); if (i + count == npages) SFSTAT_ADD(sf_rhpages_read, rhpages); i += count1; (*nios)++; } if (*nios == 0 && npages != 0) SFSTAT_INC(sf_noiocnt); return (0); } static int sendfile_getobj(struct thread *td, struct file *fp, vm_object_t *obj_res, struct vnode **vp_res, struct shmfd **shmfd_res, off_t *obj_size, int *bsize) { struct vattr va; vm_object_t obj; struct vnode *vp; struct shmfd *shmfd; int error; error = 0; vp = *vp_res = NULL; obj = NULL; shmfd = *shmfd_res = NULL; *bsize = 0; /* * The file descriptor must be a regular file and have a * backing VM object. */ if (fp->f_type == DTYPE_VNODE) { vp = fp->f_vnode; vn_lock(vp, LK_SHARED | LK_RETRY); if (vp->v_type != VREG) { error = EINVAL; goto out; } *bsize = vp->v_mount->mnt_stat.f_iosize; obj = vp->v_object; if (obj == NULL) { error = EINVAL; goto out; } /* * Use the pager size when available to simplify synchronization * with filesystems, which otherwise must atomically update both * the vnode pager size and file size. */ if (obj->type == OBJT_VNODE) { VM_OBJECT_RLOCK(obj); *obj_size = obj->un_pager.vnp.vnp_size; } else { error = VOP_GETATTR(vp, &va, td->td_ucred); if (error != 0) goto out; *obj_size = va.va_size; VM_OBJECT_RLOCK(obj); } } else if (fp->f_type == DTYPE_SHM) { shmfd = fp->f_data; obj = shmfd->shm_object; VM_OBJECT_RLOCK(obj); *obj_size = shmfd->shm_size; } else { error = EINVAL; goto out; } if ((obj->flags & OBJ_DEAD) != 0) { VM_OBJECT_RUNLOCK(obj); error = EBADF; goto out; } /* * Temporarily increase the backing VM object's reference * count so that a forced reclamation of its vnode does not * immediately destroy it. */ vm_object_reference_locked(obj); VM_OBJECT_RUNLOCK(obj); *obj_res = obj; *vp_res = vp; *shmfd_res = shmfd; out: if (vp != NULL) VOP_UNLOCK(vp); return (error); } static int sendfile_getsock(struct thread *td, int s, struct file **sock_fp, struct socket **so) { int error; *sock_fp = NULL; *so = NULL; /* * The socket must be a stream socket and connected. */ error = getsock_cap(td, s, &cap_send_rights, sock_fp, NULL, NULL); if (error != 0) return (error); *so = (*sock_fp)->f_data; if ((*so)->so_type != SOCK_STREAM) return (EINVAL); /* * SCTP one-to-one style sockets currently don't work with * sendfile(). So indicate EINVAL for now. */ if ((*so)->so_proto->pr_protocol == IPPROTO_SCTP) return (EINVAL); if (SOLISTENING(*so)) return (ENOTCONN); return (0); } int vn_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, struct thread *td) { struct file *sock_fp; struct vnode *vp; struct vm_object *obj; vm_page_t pga; struct socket *so; #ifdef KERN_TLS struct ktls_session *tls; #endif struct mbuf *m, *mh, *mhtail; struct sf_buf *sf; struct shmfd *shmfd; struct sendfile_sync *sfs; struct vattr va; off_t off, sbytes, rem, obj_size, nobj_size; int bsize, error, ext_pgs_idx, hdrlen, max_pgs, softerr; #ifdef KERN_TLS int tls_enq_cnt; #endif bool use_ext_pgs; obj = NULL; so = NULL; m = mh = NULL; sfs = NULL; #ifdef KERN_TLS tls = NULL; #endif hdrlen = sbytes = 0; softerr = 0; use_ext_pgs = false; error = sendfile_getobj(td, fp, &obj, &vp, &shmfd, &obj_size, &bsize); if (error != 0) return (error); error = sendfile_getsock(td, sockfd, &sock_fp, &so); if (error != 0) goto out; #ifdef MAC error = mac_socket_check_send(td->td_ucred, so); if (error != 0) goto out; #endif SFSTAT_INC(sf_syscalls); SFSTAT_ADD(sf_rhpages_requested, SF_READAHEAD(flags)); if (flags & SF_SYNC) { sfs = malloc(sizeof(*sfs), M_SENDFILE, M_WAITOK | M_ZERO); mtx_init(&sfs->mtx, "sendfile", NULL, MTX_DEF); cv_init(&sfs->cv, "sendfile"); sfs->waiting = true; } rem = nbytes ? omin(nbytes, obj_size - offset) : obj_size - offset; /* * Protect against multiple writers to the socket. * * XXXRW: Historically this has assumed non-interruptibility, so now * we implement that, but possibly shouldn't. */ (void)sblock(&so->so_snd, SBL_WAIT | SBL_NOINTR); #ifdef KERN_TLS tls = ktls_hold(so->so_snd.sb_tls_info); #endif /* * Loop through the pages of the file, starting with the requested * offset. Get a file page (do I/O if necessary), map the file page * into an sf_buf, attach an mbuf header to the sf_buf, and queue * it on the socket. * This is done in two loops. The inner loop turns as many pages * as it can, up to available socket buffer space, without blocking * into mbufs to have it bulk delivered into the socket send buffer. * The outer loop checks the state and available space of the socket * and takes care of the overall progress. */ for (off = offset; rem > 0; ) { struct sf_io *sfio; vm_page_t *pa; struct mbuf *m0, *mtail; int nios, space, npages, rhpages; mtail = NULL; /* * Check the socket state for ongoing connection, * no errors and space in socket buffer. * If space is low allow for the remainder of the * file to be processed if it fits the socket buffer. * Otherwise block in waiting for sufficient space * to proceed, or if the socket is nonblocking, return * to userland with EAGAIN while reporting how far * we've come. * We wait until the socket buffer has significant free * space to do bulk sends. This makes good use of file * system read ahead and allows packet segmentation * offloading hardware to take over lots of work. If * we were not careful here we would send off only one * sfbuf at a time. */ SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_lowat < so->so_snd.sb_hiwat / 2) so->so_snd.sb_lowat = so->so_snd.sb_hiwat / 2; retry_space: if (so->so_snd.sb_state & SBS_CANTSENDMORE) { error = EPIPE; SOCKBUF_UNLOCK(&so->so_snd); goto done; } else if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto done; } if ((so->so_state & SS_ISCONNECTED) == 0) { SOCKBUF_UNLOCK(&so->so_snd); error = ENOTCONN; goto done; } space = sbspace(&so->so_snd); if (space < rem && (space <= 0 || space < so->so_snd.sb_lowat)) { if (so->so_state & SS_NBIO) { SOCKBUF_UNLOCK(&so->so_snd); error = EAGAIN; goto done; } /* * sbwait drops the lock while sleeping. * When we loop back to retry_space the * state may have changed and we retest * for it. */ error = sbwait(&so->so_snd); /* * An error from sbwait usually indicates that we've * been interrupted by a signal. If we've sent anything * then return bytes sent, otherwise return the error. */ if (error != 0) { SOCKBUF_UNLOCK(&so->so_snd); goto done; } goto retry_space; } SOCKBUF_UNLOCK(&so->so_snd); /* * At the beginning of the first loop check if any headers * are specified and copy them into mbufs. Reduce space in * the socket buffer by the size of the header mbuf chain. * Clear hdr_uio here and hdrlen at the end of the first loop. */ if (hdr_uio != NULL && hdr_uio->uio_resid > 0) { hdr_uio->uio_td = td; hdr_uio->uio_rw = UIO_WRITE; #ifdef KERN_TLS if (tls != NULL) mh = m_uiotombuf(hdr_uio, M_WAITOK, space, tls->params.max_frame_len, M_EXTPG); else #endif mh = m_uiotombuf(hdr_uio, M_WAITOK, space, 0, 0); hdrlen = m_length(mh, &mhtail); space -= hdrlen; /* * If header consumed all the socket buffer space, * don't waste CPU cycles and jump to the end. */ if (space == 0) { sfio = NULL; nios = 0; goto prepend_header; } hdr_uio = NULL; } if (vp != NULL) { error = vn_lock(vp, LK_SHARED); if (error != 0) goto done; /* * Check to see if the file size has changed. */ if (obj->type == OBJT_VNODE) { VM_OBJECT_RLOCK(obj); nobj_size = obj->un_pager.vnp.vnp_size; VM_OBJECT_RUNLOCK(obj); } else { error = VOP_GETATTR(vp, &va, td->td_ucred); if (error != 0) { VOP_UNLOCK(vp); goto done; } nobj_size = va.va_size; } if (off >= nobj_size) { VOP_UNLOCK(vp); goto done; } if (nobj_size != obj_size) { obj_size = nobj_size; rem = nbytes ? omin(nbytes + offset, obj_size) : obj_size; rem -= off; } } if (space > rem) space = rem; else if (space > PAGE_SIZE) { /* * Use page boundaries when possible for large * requests. */ if (off & PAGE_MASK) space -= (PAGE_SIZE - (off & PAGE_MASK)); space = trunc_page(space); if (off & PAGE_MASK) space += (PAGE_SIZE - (off & PAGE_MASK)); } npages = howmany(space + (off & PAGE_MASK), PAGE_SIZE); /* * Calculate maximum allowed number of pages for readahead * at this iteration. If SF_USER_READAHEAD was set, we don't * do any heuristics and use exactly the value supplied by * application. Otherwise, we allow readahead up to "rem". * If application wants more, let it be, but there is no * reason to go above maxphys. Also check against "obj_size", * since vm_pager_has_page() can hint beyond EOF. */ if (flags & SF_USER_READAHEAD) { rhpages = SF_READAHEAD(flags); } else { rhpages = howmany(rem + (off & PAGE_MASK), PAGE_SIZE) - npages; rhpages += SF_READAHEAD(flags); } rhpages = min(howmany(maxphys, PAGE_SIZE), rhpages); rhpages = min(howmany(obj_size - trunc_page(off), PAGE_SIZE) - npages, rhpages); sfio = malloc(sizeof(struct sf_io) + npages * sizeof(vm_page_t), M_SENDFILE, M_WAITOK); refcount_init(&sfio->nios, 1); sfio->obj = obj; sfio->error = 0; sfio->m = NULL; sfio->npages = npages; #ifdef KERN_TLS /* * This doesn't use ktls_hold() because sfio->m will * also have a reference on 'tls' that will be valid * for all of sfio's lifetime. */ sfio->tls = tls; #endif vm_object_pip_add(obj, 1); error = sendfile_swapin(obj, sfio, &nios, off, space, rhpages, flags); if (error != 0) { if (vp != NULL) VOP_UNLOCK(vp); sendfile_iodone(sfio, NULL, 0, error); goto done; } /* * Loop and construct maximum sized mbuf chain to be bulk * dumped into socket buffer. */ pa = sfio->pa; /* * Use unmapped mbufs if enabled for TCP. Unmapped * bufs are restricted to TCP as that is what has been * tested. In particular, unmapped mbufs have not * been tested with UNIX-domain sockets. * * TLS frames always require unmapped mbufs. */ if ((mb_use_ext_pgs && so->so_proto->pr_protocol == IPPROTO_TCP) #ifdef KERN_TLS || tls != NULL #endif ) { use_ext_pgs = true; #ifdef KERN_TLS if (tls != NULL) max_pgs = num_pages(tls->params.max_frame_len); else #endif max_pgs = MBUF_PEXT_MAX_PGS; /* Start at last index, to wrap on first use. */ ext_pgs_idx = max_pgs - 1; } for (int i = 0; i < npages; i++) { /* * If a page wasn't grabbed successfully, then * trim the array. Can happen only with SF_NODISKIO. */ if (pa[i] == NULL) { SFSTAT_INC(sf_busy); fixspace(npages, i, off, &space); sfio->npages = i; softerr = EBUSY; break; } pga = pa[i]; if (pga == bogus_page) pga = vm_page_relookup(obj, sfio->pindex0 + i); if (use_ext_pgs) { off_t xfs; ext_pgs_idx++; if (ext_pgs_idx == max_pgs) { m0 = mb_alloc_ext_pgs(M_WAITOK, sendfile_free_mext_pg); if (flags & SF_NOCACHE) { m0->m_ext.ext_flags |= EXT_FLAG_NOCACHE; /* * See comment below regarding * ignoring SF_NOCACHE for the * last page. */ if ((npages - i <= max_pgs) && ((off + space) & PAGE_MASK) && (rem > space || rhpages > 0)) m0->m_ext.ext_flags |= EXT_FLAG_CACHE_LAST; } if (sfs != NULL) { m0->m_ext.ext_flags |= EXT_FLAG_SYNC; m0->m_ext.ext_arg1 = sfs; mtx_lock(&sfs->mtx); sfs->count++; mtx_unlock(&sfs->mtx); } ext_pgs_idx = 0; /* Append to mbuf chain. */ if (mtail != NULL) mtail->m_next = m0; else m = m0; mtail = m0; m0->m_epg_1st_off = vmoff(i, off) & PAGE_MASK; } if (nios) { mtail->m_flags |= M_NOTREADY; m0->m_epg_nrdy++; } m0->m_epg_pa[ext_pgs_idx] = VM_PAGE_TO_PHYS(pga); m0->m_epg_npgs++; xfs = xfsize(i, npages, off, space); m0->m_epg_last_len = xfs; MBUF_EXT_PGS_ASSERT_SANITY(m0); mtail->m_len += xfs; mtail->m_ext.ext_size += PAGE_SIZE; continue; } /* * Get a sendfile buf. When allocating the * first buffer for mbuf chain, we usually * wait as long as necessary, but this wait * can be interrupted. For consequent * buffers, do not sleep, since several * threads might exhaust the buffers and then * deadlock. */ sf = sf_buf_alloc(pga, m != NULL ? SFB_NOWAIT : SFB_CATCH); if (sf == NULL) { SFSTAT_INC(sf_allocfail); sendfile_iowait(sfio, "sfnosf"); for (int j = i; j < npages; j++) { vm_page_unwire(pa[j], PQ_INACTIVE); pa[j] = NULL; } if (m == NULL) softerr = ENOBUFS; fixspace(npages, i, off, &space); sfio->npages = i; break; } m0 = m_get(M_WAITOK, MT_DATA); m0->m_ext.ext_buf = (char *)sf_buf_kva(sf); m0->m_ext.ext_size = PAGE_SIZE; m0->m_ext.ext_arg1 = sf; m0->m_ext.ext_type = EXT_SFBUF; m0->m_ext.ext_flags = EXT_FLAG_EMBREF; m0->m_ext.ext_free = sendfile_free_mext; /* * SF_NOCACHE sets the page as being freed upon send. * However, we ignore it for the last page in 'space', * if the page is truncated, and we got more data to * send (rem > space), or if we have readahead * configured (rhpages > 0). */ if ((flags & SF_NOCACHE) && (i != npages - 1 || !((off + space) & PAGE_MASK) || !(rem > space || rhpages > 0))) m0->m_ext.ext_flags |= EXT_FLAG_NOCACHE; if (sfs != NULL) { m0->m_ext.ext_flags |= EXT_FLAG_SYNC; m0->m_ext.ext_arg2 = sfs; mtx_lock(&sfs->mtx); sfs->count++; mtx_unlock(&sfs->mtx); } m0->m_ext.ext_count = 1; m0->m_flags |= (M_EXT | M_RDONLY); if (nios) m0->m_flags |= M_NOTREADY; m0->m_data = (char *)sf_buf_kva(sf) + (vmoff(i, off) & PAGE_MASK); m0->m_len = xfsize(i, npages, off, space); /* Append to mbuf chain. */ if (mtail != NULL) mtail->m_next = m0; else m = m0; mtail = m0; } if (vp != NULL) VOP_UNLOCK(vp); /* Keep track of bytes processed. */ off += space; rem -= space; /* * Prepend header, if any. Save pointer to first mbuf * with a page. */ if (hdrlen) { prepend_header: m0 = mhtail->m_next = m; m = mh; mh = NULL; } else m0 = m; if (m == NULL) { KASSERT(softerr, ("%s: m NULL, no error", __func__)); error = softerr; sendfile_iodone(sfio, NULL, 0, 0); goto done; } /* Add the buffer chain to the socket buffer. */ KASSERT(m_length(m, NULL) == space + hdrlen, ("%s: mlen %u space %d hdrlen %d", __func__, m_length(m, NULL), space, hdrlen)); CURVNET_SET(so->so_vnet); #ifdef KERN_TLS if (tls != NULL) ktls_frame(m, tls, &tls_enq_cnt, TLS_RLTYPE_APP); #endif if (nios == 0) { /* * If sendfile_swapin() didn't initiate any I/Os, * which happens if all data is cached in VM, or if * the header consumed all socket buffer space and * sfio is NULL, then we can send data right now * without the PRUS_NOTREADY flag. */ if (sfio != NULL) sendfile_iodone(sfio, NULL, 0, 0); #ifdef KERN_TLS if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) { error = (*so->so_proto->pr_usrreqs->pru_send) (so, PRUS_NOTREADY, m, NULL, NULL, td); - soref(so); - ktls_enqueue(m, so, tls_enq_cnt); + if (error != 0) { + m_freem(m); + } else { + soref(so); + ktls_enqueue(m, so, tls_enq_cnt); + } } else #endif error = (*so->so_proto->pr_usrreqs->pru_send) (so, 0, m, NULL, NULL, td); } else { sfio->so = so; sfio->m = m0; soref(so); error = (*so->so_proto->pr_usrreqs->pru_send) (so, PRUS_NOTREADY, m, NULL, NULL, td); - sendfile_iodone(sfio, NULL, 0, 0); + sendfile_iodone(sfio, NULL, 0, error); } CURVNET_RESTORE(); - m = NULL; /* pru_send always consumes */ + m = NULL; if (error) goto done; sbytes += space + hdrlen; if (hdrlen) hdrlen = 0; if (softerr) { error = softerr; goto done; } } /* * Send trailers. Wimp out and use writev(2). */ if (trl_uio != NULL) { sbunlock(&so->so_snd); error = kern_writev(td, sockfd, trl_uio); if (error == 0) sbytes += td->td_retval[0]; goto out; } done: sbunlock(&so->so_snd); out: /* * If there was no error we have to clear td->td_retval[0] * because it may have been set by writev. */ if (error == 0) { td->td_retval[0] = 0; } if (sent != NULL) { (*sent) = sbytes; } if (obj != NULL) vm_object_deallocate(obj); if (so) fdrop(sock_fp, td); if (m) m_freem(m); if (mh) m_freem(mh); if (sfs != NULL) { mtx_lock(&sfs->mtx); if (sfs->count != 0) error = cv_wait_sig(&sfs->cv, &sfs->mtx); if (sfs->count == 0) { sendfile_sync_destroy(sfs); } else { sfs->waiting = false; mtx_unlock(&sfs->mtx); } } #ifdef KERN_TLS if (tls != NULL) ktls_free(tls); #endif if (error == ERESTART) error = EINTR; return (error); } static int sendfile(struct thread *td, struct sendfile_args *uap, int compat) { struct sf_hdtr hdtr; struct uio *hdr_uio, *trl_uio; struct file *fp; off_t sbytes; int error; /* * File offset must be positive. If it goes beyond EOF * we send only the header/trailer and no payload data. */ if (uap->offset < 0) return (EINVAL); sbytes = 0; hdr_uio = trl_uio = NULL; if (uap->hdtr != NULL) { error = copyin(uap->hdtr, &hdtr, sizeof(hdtr)); if (error != 0) goto out; if (hdtr.headers != NULL) { error = copyinuio(hdtr.headers, hdtr.hdr_cnt, &hdr_uio); if (error != 0) goto out; #ifdef COMPAT_FREEBSD4 /* * In FreeBSD < 5.0 the nbytes to send also included * the header. If compat is specified subtract the * header size from nbytes. */ if (compat) { if (uap->nbytes > hdr_uio->uio_resid) uap->nbytes -= hdr_uio->uio_resid; else uap->nbytes = 0; } #endif } if (hdtr.trailers != NULL) { error = copyinuio(hdtr.trailers, hdtr.trl_cnt, &trl_uio); if (error != 0) goto out; } } AUDIT_ARG_FD(uap->fd); /* * sendfile(2) can start at any offset within a file so we require * CAP_READ+CAP_SEEK = CAP_PREAD. */ if ((error = fget_read(td, uap->fd, &cap_pread_rights, &fp)) != 0) goto out; error = fo_sendfile(fp, uap->s, hdr_uio, trl_uio, uap->offset, uap->nbytes, &sbytes, uap->flags, td); fdrop(fp, td); if (uap->sbytes != NULL) copyout(&sbytes, uap->sbytes, sizeof(off_t)); out: free(hdr_uio, M_IOV); free(trl_uio, M_IOV); return (error); } /* * sendfile(2) * * int sendfile(int fd, int s, off_t offset, size_t nbytes, * struct sf_hdtr *hdtr, off_t *sbytes, int flags) * * Send a file specified by 'fd' and starting at 'offset' to a socket * specified by 's'. Send only 'nbytes' of the file or until EOF if nbytes == * 0. Optionally add a header and/or trailer to the socket output. If * specified, write the total number of bytes sent into *sbytes. */ int sys_sendfile(struct thread *td, struct sendfile_args *uap) { return (sendfile(td, uap, 0)); } #ifdef COMPAT_FREEBSD4 int freebsd4_sendfile(struct thread *td, struct freebsd4_sendfile_args *uap) { struct sendfile_args args; args.fd = uap->fd; args.s = uap->s; args.offset = uap->offset; args.nbytes = uap->nbytes; args.hdtr = uap->hdtr; args.sbytes = uap->sbytes; args.flags = uap->flags; return (sendfile(td, &args, 1)); } #endif /* COMPAT_FREEBSD4 */ diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c index 2a167eb68a22..0ca87bfc522a 100644 --- a/sys/kern/uipc_socket.c +++ b/sys/kern/uipc_socket.c @@ -1,4425 +1,4420 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993 * The Regents of the University of California. * Copyright (c) 2004 The FreeBSD Foundation * Copyright (c) 2004-2008 Robert N. M. Watson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)uipc_socket.c 8.3 (Berkeley) 4/15/94 */ /* * Comments on the socket life cycle: * * soalloc() sets of socket layer state for a socket, called only by * socreate() and sonewconn(). Socket layer private. * * sodealloc() tears down socket layer state for a socket, called only by * sofree() and sonewconn(). Socket layer private. * * pru_attach() associates protocol layer state with an allocated socket; * called only once, may fail, aborting socket allocation. This is called * from socreate() and sonewconn(). Socket layer private. * * pru_detach() disassociates protocol layer state from an attached socket, * and will be called exactly once for sockets in which pru_attach() has * been successfully called. If pru_attach() returned an error, * pru_detach() will not be called. Socket layer private. * * pru_abort() and pru_close() notify the protocol layer that the last * consumer of a socket is starting to tear down the socket, and that the * protocol should terminate the connection. Historically, pru_abort() also * detached protocol state from the socket state, but this is no longer the * case. * * socreate() creates a socket and attaches protocol state. This is a public * interface that may be used by socket layer consumers to create new * sockets. * * sonewconn() creates a socket and attaches protocol state. This is a * public interface that may be used by protocols to create new sockets when * a new connection is received and will be available for accept() on a * listen socket. * * soclose() destroys a socket after possibly waiting for it to disconnect. * This is a public interface that socket consumers should use to close and * release a socket when done with it. * * soabort() destroys a socket without waiting for it to disconnect (used * only for incoming connections that are already partially or fully * connected). This is used internally by the socket layer when clearing * listen socket queues (due to overflow or close on the listen socket), but * is also a public interface protocols may use to abort connections in * their incomplete listen queues should they no longer be required. Sockets * placed in completed connection listen queues should not be aborted for * reasons described in the comment above the soclose() implementation. This * is not a general purpose close routine, and except in the specific * circumstances described here, should not be used. * * sofree() will free a socket and its protocol state if all references on * the socket have been released, and is the public interface to attempt to * free a socket when a reference is removed. This is a socket layer private * interface. * * NOTE: In addition to socreate() and soclose(), which provide a single * socket reference to the consumer to be managed as required, there are two * calls to explicitly manage socket references, soref(), and sorele(). * Currently, these are generally required only when transitioning a socket * from a listen queue to a file descriptor, in order to prevent garbage * collection of the socket at an untimely moment. For a number of reasons, * these interfaces are not preferred, and should be avoided. * * NOTE: With regard to VNETs the general rule is that callers do not set * curvnet. Exceptions to this rule include soabort(), sodisconnect(), * sofree() (and with that sorele(), sotryfree()), as well as sonewconn() * and sorflush(), which are usually called from a pre-set VNET context. * sopoll() currently does not need a VNET context to be set. */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.h" #include "opt_kern_tls.h" #include "opt_sctp.h" #include #include #include #include #include #include #include #include #include #include #include #include /* for struct knote */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef COMPAT_FREEBSD32 #include #include #include #endif static int soreceive_rcvoob(struct socket *so, struct uio *uio, int flags); static void so_rdknl_lock(void *); static void so_rdknl_unlock(void *); static void so_rdknl_assert_lock(void *, int); static void so_wrknl_lock(void *); static void so_wrknl_unlock(void *); static void so_wrknl_assert_lock(void *, int); static void filt_sordetach(struct knote *kn); static int filt_soread(struct knote *kn, long hint); static void filt_sowdetach(struct knote *kn); static int filt_sowrite(struct knote *kn, long hint); static int filt_soempty(struct knote *kn, long hint); static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id); fo_kqfilter_t soo_kqfilter; static struct filterops soread_filtops = { .f_isfd = 1, .f_detach = filt_sordetach, .f_event = filt_soread, }; static struct filterops sowrite_filtops = { .f_isfd = 1, .f_detach = filt_sowdetach, .f_event = filt_sowrite, }; static struct filterops soempty_filtops = { .f_isfd = 1, .f_detach = filt_sowdetach, .f_event = filt_soempty, }; so_gen_t so_gencnt; /* generation count for sockets */ MALLOC_DEFINE(M_SONAME, "soname", "socket name"); MALLOC_DEFINE(M_PCB, "pcb", "protocol control block"); #define VNET_SO_ASSERT(so) \ VNET_ASSERT(curvnet != NULL, \ ("%s:%d curvnet is NULL, so=%p", __func__, __LINE__, (so))); VNET_DEFINE(struct hhook_head *, socket_hhh[HHOOK_SOCKET_LAST + 1]); #define V_socket_hhh VNET(socket_hhh) /* * Limit on the number of connections in the listen queue waiting * for accept(2). * NB: The original sysctl somaxconn is still available but hidden * to prevent confusion about the actual purpose of this number. */ static u_int somaxconn = SOMAXCONN; static int sysctl_somaxconn(SYSCTL_HANDLER_ARGS) { int error; int val; val = somaxconn; error = sysctl_handle_int(oidp, &val, 0, req); if (error || !req->newptr ) return (error); /* * The purpose of the UINT_MAX / 3 limit, is so that the formula * 3 * so_qlimit / 2 * below, will not overflow. */ if (val < 1 || val > UINT_MAX / 3) return (EINVAL); somaxconn = val; return (0); } SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue, CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 0, sizeof(int), sysctl_somaxconn, "I", "Maximum listen socket pending connection accept queue size"); SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT, 0, sizeof(int), sysctl_somaxconn, "I", "Maximum listen socket pending connection accept queue size (compat)"); static int numopensockets; SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD, &numopensockets, 0, "Number of open sockets"); /* * accept_mtx locks down per-socket fields relating to accept queues. See * socketvar.h for an annotation of the protected fields of struct socket. */ struct mtx accept_mtx; MTX_SYSINIT(accept_mtx, &accept_mtx, "accept", MTX_DEF); /* * so_global_mtx protects so_gencnt, numopensockets, and the per-socket * so_gencnt field. */ static struct mtx so_global_mtx; MTX_SYSINIT(so_global_mtx, &so_global_mtx, "so_glabel", MTX_DEF); /* * General IPC sysctl name space, used by sockets and a variety of other IPC * types. */ SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "IPC"); /* * Initialize the socket subsystem and set up the socket * memory allocator. */ static uma_zone_t socket_zone; int maxsockets; static void socket_zone_change(void *tag) { maxsockets = uma_zone_set_max(socket_zone, maxsockets); } static void socket_hhook_register(int subtype) { if (hhook_head_register(HHOOK_TYPE_SOCKET, subtype, &V_socket_hhh[subtype], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) printf("%s: WARNING: unable to register hook\n", __func__); } static void socket_hhook_deregister(int subtype) { if (hhook_head_deregister(V_socket_hhh[subtype]) != 0) printf("%s: WARNING: unable to deregister hook\n", __func__); } static void socket_init(void *tag) { socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); maxsockets = uma_zone_set_max(socket_zone, maxsockets); uma_zone_set_warning(socket_zone, "kern.ipc.maxsockets limit reached"); EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL, EVENTHANDLER_PRI_FIRST); } SYSINIT(socket, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_init, NULL); static void socket_vnet_init(const void *unused __unused) { int i; /* We expect a contiguous range */ for (i = 0; i <= HHOOK_SOCKET_LAST; i++) socket_hhook_register(i); } VNET_SYSINIT(socket_vnet_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_vnet_init, NULL); static void socket_vnet_uninit(const void *unused __unused) { int i; for (i = 0; i <= HHOOK_SOCKET_LAST; i++) socket_hhook_deregister(i); } VNET_SYSUNINIT(socket_vnet_uninit, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, socket_vnet_uninit, NULL); /* * Initialise maxsockets. This SYSINIT must be run after * tunable_mbinit(). */ static void init_maxsockets(void *ignored) { TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); maxsockets = imax(maxsockets, maxfiles); } SYSINIT(param, SI_SUB_TUNABLES, SI_ORDER_ANY, init_maxsockets, NULL); /* * Sysctl to get and set the maximum global sockets limit. Notify protocols * of the change so that they can update their dependent limits as required. */ static int sysctl_maxsockets(SYSCTL_HANDLER_ARGS) { int error, newmaxsockets; newmaxsockets = maxsockets; error = sysctl_handle_int(oidp, &newmaxsockets, 0, req); if (error == 0 && req->newptr) { if (newmaxsockets > maxsockets && newmaxsockets <= maxfiles) { maxsockets = newmaxsockets; EVENTHANDLER_INVOKE(maxsockets_change); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, maxsockets, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &maxsockets, 0, sysctl_maxsockets, "IU", "Maximum number of sockets available"); /* * Socket operation routines. These routines are called by the routines in * sys_socket.c or from a system process, and implement the semantics of * socket operations by switching out to the protocol specific routines. */ /* * Get a socket structure from our zone, and initialize it. Note that it * would probably be better to allocate socket and PCB at the same time, but * I'm not convinced that all the protocols can be easily modified to do * this. * * soalloc() returns a socket with a ref count of 0. */ static struct socket * soalloc(struct vnet *vnet) { struct socket *so; so = uma_zalloc(socket_zone, M_NOWAIT | M_ZERO); if (so == NULL) return (NULL); #ifdef MAC if (mac_socket_init(so, M_NOWAIT) != 0) { uma_zfree(socket_zone, so); return (NULL); } #endif if (khelp_init_osd(HELPER_CLASS_SOCKET, &so->osd)) { uma_zfree(socket_zone, so); return (NULL); } /* * The socket locking protocol allows to lock 2 sockets at a time, * however, the first one must be a listening socket. WITNESS lacks * a feature to change class of an existing lock, so we use DUPOK. */ mtx_init(&so->so_lock, "socket", NULL, MTX_DEF | MTX_DUPOK); SOCKBUF_LOCK_INIT(&so->so_snd, "so_snd"); SOCKBUF_LOCK_INIT(&so->so_rcv, "so_rcv"); so->so_rcv.sb_sel = &so->so_rdsel; so->so_snd.sb_sel = &so->so_wrsel; sx_init(&so->so_snd.sb_sx, "so_snd_sx"); sx_init(&so->so_rcv.sb_sx, "so_rcv_sx"); TAILQ_INIT(&so->so_snd.sb_aiojobq); TAILQ_INIT(&so->so_rcv.sb_aiojobq); TASK_INIT(&so->so_snd.sb_aiotask, 0, soaio_snd, so); TASK_INIT(&so->so_rcv.sb_aiotask, 0, soaio_rcv, so); #ifdef VIMAGE VNET_ASSERT(vnet != NULL, ("%s:%d vnet is NULL, so=%p", __func__, __LINE__, so)); so->so_vnet = vnet; #endif /* We shouldn't need the so_global_mtx */ if (hhook_run_socket(so, NULL, HHOOK_SOCKET_CREATE)) { /* Do we need more comprehensive error returns? */ uma_zfree(socket_zone, so); return (NULL); } mtx_lock(&so_global_mtx); so->so_gencnt = ++so_gencnt; ++numopensockets; #ifdef VIMAGE vnet->vnet_sockcnt++; #endif mtx_unlock(&so_global_mtx); return (so); } /* * Free the storage associated with a socket at the socket layer, tear down * locks, labels, etc. All protocol state is assumed already to have been * torn down (and possibly never set up) by the caller. */ static void sodealloc(struct socket *so) { KASSERT(so->so_count == 0, ("sodealloc(): so_count %d", so->so_count)); KASSERT(so->so_pcb == NULL, ("sodealloc(): so_pcb != NULL")); mtx_lock(&so_global_mtx); so->so_gencnt = ++so_gencnt; --numopensockets; /* Could be below, but faster here. */ #ifdef VIMAGE VNET_ASSERT(so->so_vnet != NULL, ("%s:%d so_vnet is NULL, so=%p", __func__, __LINE__, so)); so->so_vnet->vnet_sockcnt--; #endif mtx_unlock(&so_global_mtx); #ifdef MAC mac_socket_destroy(so); #endif hhook_run_socket(so, NULL, HHOOK_SOCKET_CLOSE); khelp_destroy_osd(&so->osd); if (SOLISTENING(so)) { if (so->sol_accept_filter != NULL) accept_filt_setopt(so, NULL); } else { if (so->so_rcv.sb_hiwat) (void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_rcv.sb_hiwat, 0, RLIM_INFINITY); if (so->so_snd.sb_hiwat) (void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.sb_hiwat, 0, RLIM_INFINITY); sx_destroy(&so->so_snd.sb_sx); sx_destroy(&so->so_rcv.sb_sx); SOCKBUF_LOCK_DESTROY(&so->so_snd); SOCKBUF_LOCK_DESTROY(&so->so_rcv); } crfree(so->so_cred); mtx_destroy(&so->so_lock); uma_zfree(socket_zone, so); } /* * socreate returns a socket with a ref count of 1. The socket should be * closed with soclose(). */ int socreate(int dom, struct socket **aso, int type, int proto, struct ucred *cred, struct thread *td) { struct protosw *prp; struct socket *so; int error; if (proto) prp = pffindproto(dom, proto, type); else prp = pffindtype(dom, type); if (prp == NULL) { /* No support for domain. */ if (pffinddomain(dom) == NULL) return (EAFNOSUPPORT); /* No support for socket type. */ if (proto == 0 && type != 0) return (EPROTOTYPE); return (EPROTONOSUPPORT); } if (prp->pr_usrreqs->pru_attach == NULL || prp->pr_usrreqs->pru_attach == pru_attach_notsupp) return (EPROTONOSUPPORT); if (IN_CAPABILITY_MODE(td) && (prp->pr_flags & PR_CAPATTACH) == 0) return (ECAPMODE); if (prison_check_af(cred, prp->pr_domain->dom_family) != 0) return (EPROTONOSUPPORT); if (prp->pr_type != type) return (EPROTOTYPE); so = soalloc(CRED_TO_VNET(cred)); if (so == NULL) return (ENOBUFS); so->so_type = type; so->so_cred = crhold(cred); if ((prp->pr_domain->dom_family == PF_INET) || (prp->pr_domain->dom_family == PF_INET6) || (prp->pr_domain->dom_family == PF_ROUTE)) so->so_fibnum = td->td_proc->p_fibnum; else so->so_fibnum = 0; so->so_proto = prp; #ifdef MAC mac_socket_create(cred, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); /* * Auto-sizing of socket buffers is managed by the protocols and * the appropriate flags must be set in the pru_attach function. */ CURVNET_SET(so->so_vnet); error = (*prp->pr_usrreqs->pru_attach)(so, proto, td); CURVNET_RESTORE(); if (error) { sodealloc(so); return (error); } soref(so); *aso = so; return (0); } #ifdef REGRESSION static int regression_sonewconn_earlytest = 1; SYSCTL_INT(_regression, OID_AUTO, sonewconn_earlytest, CTLFLAG_RW, ®ression_sonewconn_earlytest, 0, "Perform early sonewconn limit test"); #endif static struct timeval overinterval = { 60, 0 }; SYSCTL_TIMEVAL_SEC(_kern_ipc, OID_AUTO, sooverinterval, CTLFLAG_RW, &overinterval, "Delay in seconds between warnings for listen socket overflows"); /* * When an attempt at a new connection is noted on a socket which accepts * connections, sonewconn is called. If the connection is possible (subject * to space constraints, etc.) then we allocate a new structure, properly * linked into the data structure of the original socket, and return this. * Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED. * * Note: the ref count on the socket is 0 on return. */ struct socket * sonewconn(struct socket *head, int connstatus) { struct sbuf descrsb; struct socket *so; int len, overcount; u_int qlen; const char localprefix[] = "local:"; char descrbuf[SUNPATHLEN + sizeof(localprefix)]; #if defined(INET6) char addrbuf[INET6_ADDRSTRLEN]; #elif defined(INET) char addrbuf[INET_ADDRSTRLEN]; #endif bool dolog, over; SOLISTEN_LOCK(head); over = (head->sol_qlen > 3 * head->sol_qlimit / 2); #ifdef REGRESSION if (regression_sonewconn_earlytest && over) { #else if (over) { #endif head->sol_overcount++; dolog = !!ratecheck(&head->sol_lastover, &overinterval); /* * If we're going to log, copy the overflow count and queue * length from the listen socket before dropping the lock. * Also, reset the overflow count. */ if (dolog) { overcount = head->sol_overcount; head->sol_overcount = 0; qlen = head->sol_qlen; } SOLISTEN_UNLOCK(head); if (dolog) { /* * Try to print something descriptive about the * socket for the error message. */ sbuf_new(&descrsb, descrbuf, sizeof(descrbuf), SBUF_FIXEDLEN); switch (head->so_proto->pr_domain->dom_family) { #if defined(INET) || defined(INET6) #ifdef INET case AF_INET: #endif #ifdef INET6 case AF_INET6: if (head->so_proto->pr_domain->dom_family == AF_INET6 || (sotoinpcb(head)->inp_inc.inc_flags & INC_ISIPV6)) { ip6_sprintf(addrbuf, &sotoinpcb(head)->inp_inc.inc6_laddr); sbuf_printf(&descrsb, "[%s]", addrbuf); } else #endif { #ifdef INET inet_ntoa_r( sotoinpcb(head)->inp_inc.inc_laddr, addrbuf); sbuf_cat(&descrsb, addrbuf); #endif } sbuf_printf(&descrsb, ":%hu (proto %u)", ntohs(sotoinpcb(head)->inp_inc.inc_lport), head->so_proto->pr_protocol); break; #endif /* INET || INET6 */ case AF_UNIX: sbuf_cat(&descrsb, localprefix); if (sotounpcb(head)->unp_addr != NULL) len = sotounpcb(head)->unp_addr->sun_len - offsetof(struct sockaddr_un, sun_path); else len = 0; if (len > 0) sbuf_bcat(&descrsb, sotounpcb(head)->unp_addr->sun_path, len); else sbuf_cat(&descrsb, "(unknown)"); break; } /* * If we can't print something more specific, at least * print the domain name. */ if (sbuf_finish(&descrsb) != 0 || sbuf_len(&descrsb) <= 0) { sbuf_clear(&descrsb); sbuf_cat(&descrsb, head->so_proto->pr_domain->dom_name ?: "unknown"); sbuf_finish(&descrsb); } KASSERT(sbuf_len(&descrsb) > 0, ("%s: sbuf creation failed", __func__)); log(LOG_DEBUG, "%s: pcb %p (%s): Listen queue overflow: " "%i already in queue awaiting acceptance " "(%d occurrences)\n", __func__, head->so_pcb, sbuf_data(&descrsb), qlen, overcount); sbuf_delete(&descrsb); overcount = 0; } return (NULL); } SOLISTEN_UNLOCK(head); VNET_ASSERT(head->so_vnet != NULL, ("%s: so %p vnet is NULL", __func__, head)); so = soalloc(head->so_vnet); if (so == NULL) { log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " "limit reached or out of memory\n", __func__, head->so_pcb); return (NULL); } so->so_listen = head; so->so_type = head->so_type; so->so_options = head->so_options & ~SO_ACCEPTCONN; so->so_linger = head->so_linger; so->so_state = head->so_state | SS_NOFDREF; so->so_fibnum = head->so_fibnum; so->so_proto = head->so_proto; so->so_cred = crhold(head->so_cred); #ifdef MAC mac_socket_newconn(head, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); VNET_SO_ASSERT(head); if (soreserve(so, head->sol_sbsnd_hiwat, head->sol_sbrcv_hiwat)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", __func__, head->so_pcb); return (NULL); } if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n", __func__, head->so_pcb); return (NULL); } so->so_rcv.sb_lowat = head->sol_sbrcv_lowat; so->so_snd.sb_lowat = head->sol_sbsnd_lowat; so->so_rcv.sb_timeo = head->sol_sbrcv_timeo; so->so_snd.sb_timeo = head->sol_sbsnd_timeo; so->so_rcv.sb_flags |= head->sol_sbrcv_flags & SB_AUTOSIZE; so->so_snd.sb_flags |= head->sol_sbsnd_flags & SB_AUTOSIZE; SOLISTEN_LOCK(head); if (head->sol_accept_filter != NULL) connstatus = 0; so->so_state |= connstatus; soref(head); /* A socket on (in)complete queue refs head. */ if (connstatus) { TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); so->so_qstate = SQ_COMP; head->sol_qlen++; solisten_wakeup(head); /* unlocks */ } else { /* * Keep removing sockets from the head until there's room for * us to insert on the tail. In pre-locking revisions, this * was a simple if(), but as we could be racing with other * threads and soabort() requires dropping locks, we must * loop waiting for the condition to be true. */ while (head->sol_incqlen > head->sol_qlimit) { struct socket *sp; sp = TAILQ_FIRST(&head->sol_incomp); TAILQ_REMOVE(&head->sol_incomp, sp, so_list); head->sol_incqlen--; SOCK_LOCK(sp); sp->so_qstate = SQ_NONE; sp->so_listen = NULL; SOCK_UNLOCK(sp); sorele(head); /* does SOLISTEN_UNLOCK, head stays */ soabort(sp); SOLISTEN_LOCK(head); } TAILQ_INSERT_TAIL(&head->sol_incomp, so, so_list); so->so_qstate = SQ_INCOMP; head->sol_incqlen++; SOLISTEN_UNLOCK(head); } return (so); } #if defined(SCTP) || defined(SCTP_SUPPORT) /* * Socket part of sctp_peeloff(). Detach a new socket from an * association. The new socket is returned with a reference. */ struct socket * sopeeloff(struct socket *head) { struct socket *so; VNET_ASSERT(head->so_vnet != NULL, ("%s:%d so_vnet is NULL, head=%p", __func__, __LINE__, head)); so = soalloc(head->so_vnet); if (so == NULL) { log(LOG_DEBUG, "%s: pcb %p: New socket allocation failure: " "limit reached or out of memory\n", __func__, head->so_pcb); return (NULL); } so->so_type = head->so_type; so->so_options = head->so_options; so->so_linger = head->so_linger; so->so_state = (head->so_state & SS_NBIO) | SS_ISCONNECTED; so->so_fibnum = head->so_fibnum; so->so_proto = head->so_proto; so->so_cred = crhold(head->so_cred); #ifdef MAC mac_socket_newconn(head, so); #endif knlist_init(&so->so_rdsel.si_note, so, so_rdknl_lock, so_rdknl_unlock, so_rdknl_assert_lock); knlist_init(&so->so_wrsel.si_note, so, so_wrknl_lock, so_wrknl_unlock, so_wrknl_assert_lock); VNET_SO_ASSERT(head); if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: soreserve() failed\n", __func__, head->so_pcb); return (NULL); } if ((*so->so_proto->pr_usrreqs->pru_attach)(so, 0, NULL)) { sodealloc(so); log(LOG_DEBUG, "%s: pcb %p: pru_attach() failed\n", __func__, head->so_pcb); return (NULL); } so->so_rcv.sb_lowat = head->so_rcv.sb_lowat; so->so_snd.sb_lowat = head->so_snd.sb_lowat; so->so_rcv.sb_timeo = head->so_rcv.sb_timeo; so->so_snd.sb_timeo = head->so_snd.sb_timeo; so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE; so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE; soref(so); return (so); } #endif /* SCTP */ int sobind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam, td); CURVNET_RESTORE(); return (error); } int sobindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = (*so->so_proto->pr_usrreqs->pru_bindat)(fd, so, nam, td); CURVNET_RESTORE(); return (error); } /* * solisten() transitions a socket from a non-listening state to a listening * state, but can also be used to update the listen queue depth on an * existing listen socket. The protocol will call back into the sockets * layer using solisten_proto_check() and solisten_proto() to check and set * socket-layer listen state. Call backs are used so that the protocol can * acquire both protocol and socket layer locks in whatever order is required * by the protocol. * * Protocol implementors are advised to hold the socket lock across the * socket-layer test and set to avoid races at the socket layer. */ int solisten(struct socket *so, int backlog, struct thread *td) { int error; CURVNET_SET(so->so_vnet); error = (*so->so_proto->pr_usrreqs->pru_listen)(so, backlog, td); CURVNET_RESTORE(); return (error); } int solisten_proto_check(struct socket *so) { SOCK_LOCK_ASSERT(so); if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) return (EINVAL); return (0); } void solisten_proto(struct socket *so, int backlog) { int sbrcv_lowat, sbsnd_lowat; u_int sbrcv_hiwat, sbsnd_hiwat; short sbrcv_flags, sbsnd_flags; sbintime_t sbrcv_timeo, sbsnd_timeo; SOCK_LOCK_ASSERT(so); if (SOLISTENING(so)) goto listening; /* * Change this socket to listening state. */ sbrcv_lowat = so->so_rcv.sb_lowat; sbsnd_lowat = so->so_snd.sb_lowat; sbrcv_hiwat = so->so_rcv.sb_hiwat; sbsnd_hiwat = so->so_snd.sb_hiwat; sbrcv_flags = so->so_rcv.sb_flags; sbsnd_flags = so->so_snd.sb_flags; sbrcv_timeo = so->so_rcv.sb_timeo; sbsnd_timeo = so->so_snd.sb_timeo; sbdestroy(&so->so_snd, so); sbdestroy(&so->so_rcv, so); sx_destroy(&so->so_snd.sb_sx); sx_destroy(&so->so_rcv.sb_sx); SOCKBUF_LOCK_DESTROY(&so->so_snd); SOCKBUF_LOCK_DESTROY(&so->so_rcv); #ifdef INVARIANTS bzero(&so->so_rcv, sizeof(struct socket) - offsetof(struct socket, so_rcv)); #endif so->sol_sbrcv_lowat = sbrcv_lowat; so->sol_sbsnd_lowat = sbsnd_lowat; so->sol_sbrcv_hiwat = sbrcv_hiwat; so->sol_sbsnd_hiwat = sbsnd_hiwat; so->sol_sbrcv_flags = sbrcv_flags; so->sol_sbsnd_flags = sbsnd_flags; so->sol_sbrcv_timeo = sbrcv_timeo; so->sol_sbsnd_timeo = sbsnd_timeo; so->sol_qlen = so->sol_incqlen = 0; TAILQ_INIT(&so->sol_incomp); TAILQ_INIT(&so->sol_comp); so->sol_accept_filter = NULL; so->sol_accept_filter_arg = NULL; so->sol_accept_filter_str = NULL; so->sol_upcall = NULL; so->sol_upcallarg = NULL; so->so_options |= SO_ACCEPTCONN; listening: if (backlog < 0 || backlog > somaxconn) backlog = somaxconn; so->sol_qlimit = backlog; } /* * Wakeup listeners/subsystems once we have a complete connection. * Enters with lock, returns unlocked. */ void solisten_wakeup(struct socket *sol) { if (sol->sol_upcall != NULL) (void )sol->sol_upcall(sol, sol->sol_upcallarg, M_NOWAIT); else { selwakeuppri(&sol->so_rdsel, PSOCK); KNOTE_LOCKED(&sol->so_rdsel.si_note, 0); } SOLISTEN_UNLOCK(sol); wakeup_one(&sol->sol_comp); if ((sol->so_state & SS_ASYNC) && sol->so_sigio != NULL) pgsigio(&sol->so_sigio, SIGIO, 0); } /* * Return single connection off a listening socket queue. Main consumer of * the function is kern_accept4(). Some modules, that do their own accept * management also use the function. * * Listening socket must be locked on entry and is returned unlocked on * return. * The flags argument is set of accept4(2) flags and ACCEPT4_INHERIT. */ int solisten_dequeue(struct socket *head, struct socket **ret, int flags) { struct socket *so; int error; SOLISTEN_LOCK_ASSERT(head); while (!(head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp) && head->so_error == 0) { error = msleep(&head->sol_comp, &head->so_lock, PSOCK | PCATCH, "accept", 0); if (error != 0) { SOLISTEN_UNLOCK(head); return (error); } } if (head->so_error) { error = head->so_error; head->so_error = 0; } else if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->sol_comp)) error = EWOULDBLOCK; else error = 0; if (error) { SOLISTEN_UNLOCK(head); return (error); } so = TAILQ_FIRST(&head->sol_comp); SOCK_LOCK(so); KASSERT(so->so_qstate == SQ_COMP, ("%s: so %p not SQ_COMP", __func__, so)); soref(so); head->sol_qlen--; so->so_qstate = SQ_NONE; so->so_listen = NULL; TAILQ_REMOVE(&head->sol_comp, so, so_list); if (flags & ACCEPT4_INHERIT) so->so_state |= (head->so_state & SS_NBIO); else so->so_state |= (flags & SOCK_NONBLOCK) ? SS_NBIO : 0; SOCK_UNLOCK(so); sorele(head); *ret = so; return (0); } /* * Evaluate the reference count and named references on a socket; if no * references remain, free it. This should be called whenever a reference is * released, such as in sorele(), but also when named reference flags are * cleared in socket or protocol code. * * sofree() will free the socket if: * * - There are no outstanding file descriptor references or related consumers * (so_count == 0). * * - The socket has been closed by user space, if ever open (SS_NOFDREF). * * - The protocol does not have an outstanding strong reference on the socket * (SS_PROTOREF). * * - The socket is not in a completed connection queue, so a process has been * notified that it is present. If it is removed, the user process may * block in accept() despite select() saying the socket was ready. */ void sofree(struct socket *so) { struct protosw *pr = so->so_proto; SOCK_LOCK_ASSERT(so); if ((so->so_state & SS_NOFDREF) == 0 || so->so_count != 0 || (so->so_state & SS_PROTOREF) || (so->so_qstate == SQ_COMP)) { SOCK_UNLOCK(so); return; } if (!SOLISTENING(so) && so->so_qstate == SQ_INCOMP) { struct socket *sol; sol = so->so_listen; KASSERT(sol, ("%s: so %p on incomp of NULL", __func__, so)); /* * To solve race between close of a listening socket and * a socket on its incomplete queue, we need to lock both. * The order is first listening socket, then regular. * Since we don't have SS_NOFDREF neither SS_PROTOREF, this * function and the listening socket are the only pointers * to so. To preserve so and sol, we reference both and then * relock. * After relock the socket may not move to so_comp since it * doesn't have PCB already, but it may be removed from * so_incomp. If that happens, we share responsiblity on * freeing the socket, but soclose() has already removed * it from queue. */ soref(sol); soref(so); SOCK_UNLOCK(so); SOLISTEN_LOCK(sol); SOCK_LOCK(so); if (so->so_qstate == SQ_INCOMP) { KASSERT(so->so_listen == sol, ("%s: so %p migrated out of sol %p", __func__, so, sol)); TAILQ_REMOVE(&sol->sol_incomp, so, so_list); sol->sol_incqlen--; /* This is guarenteed not to be the last. */ refcount_release(&sol->so_count); so->so_qstate = SQ_NONE; so->so_listen = NULL; } else KASSERT(so->so_listen == NULL, ("%s: so %p not on (in)comp with so_listen", __func__, so)); sorele(sol); KASSERT(so->so_count == 1, ("%s: so %p count %u", __func__, so, so->so_count)); so->so_count = 0; } if (SOLISTENING(so)) so->so_error = ECONNABORTED; SOCK_UNLOCK(so); if (so->so_dtor != NULL) so->so_dtor(so); VNET_SO_ASSERT(so); if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL) (*pr->pr_domain->dom_dispose)(so); if (pr->pr_usrreqs->pru_detach != NULL) (*pr->pr_usrreqs->pru_detach)(so); /* * From this point on, we assume that no other references to this * socket exist anywhere else in the stack. Therefore, no locks need * to be acquired or held. * * We used to do a lot of socket buffer and socket locking here, as * well as invoke sorflush() and perform wakeups. The direct call to * dom_dispose() and sbdestroy() are an inlining of what was * necessary from sorflush(). * * Notice that the socket buffer and kqueue state are torn down * before calling pru_detach. This means that protocols shold not * assume they can perform socket wakeups, etc, in their detach code. */ if (!SOLISTENING(so)) { sbdestroy(&so->so_snd, so); sbdestroy(&so->so_rcv, so); } seldrain(&so->so_rdsel); seldrain(&so->so_wrsel); knlist_destroy(&so->so_rdsel.si_note); knlist_destroy(&so->so_wrsel.si_note); sodealloc(so); } /* * Close a socket on last file table reference removal. Initiate disconnect * if connected. Free socket when disconnect complete. * * This function will sorele() the socket. Note that soclose() may be called * prior to the ref count reaching zero. The actual socket structure will * not be freed until the ref count reaches zero. */ int soclose(struct socket *so) { struct accept_queue lqueue; bool listening; int error = 0; KASSERT(!(so->so_state & SS_NOFDREF), ("soclose: SS_NOFDREF on enter")); CURVNET_SET(so->so_vnet); funsetown(&so->so_sigio); if (so->so_state & SS_ISCONNECTED) { if ((so->so_state & SS_ISDISCONNECTING) == 0) { error = sodisconnect(so); if (error) { if (error == ENOTCONN) error = 0; goto drop; } } if ((so->so_options & SO_LINGER) != 0 && so->so_linger != 0) { if ((so->so_state & SS_ISDISCONNECTING) && (so->so_state & SS_NBIO)) goto drop; while (so->so_state & SS_ISCONNECTED) { error = tsleep(&so->so_timeo, PSOCK | PCATCH, "soclos", so->so_linger * hz); if (error) break; } } } drop: if (so->so_proto->pr_usrreqs->pru_close != NULL) (*so->so_proto->pr_usrreqs->pru_close)(so); SOCK_LOCK(so); if ((listening = (so->so_options & SO_ACCEPTCONN))) { struct socket *sp; TAILQ_INIT(&lqueue); TAILQ_SWAP(&lqueue, &so->sol_incomp, socket, so_list); TAILQ_CONCAT(&lqueue, &so->sol_comp, so_list); so->sol_qlen = so->sol_incqlen = 0; TAILQ_FOREACH(sp, &lqueue, so_list) { SOCK_LOCK(sp); sp->so_qstate = SQ_NONE; sp->so_listen = NULL; SOCK_UNLOCK(sp); /* Guaranteed not to be the last. */ refcount_release(&so->so_count); } } KASSERT((so->so_state & SS_NOFDREF) == 0, ("soclose: NOFDREF")); so->so_state |= SS_NOFDREF; sorele(so); if (listening) { struct socket *sp, *tsp; TAILQ_FOREACH_SAFE(sp, &lqueue, so_list, tsp) { SOCK_LOCK(sp); if (sp->so_count == 0) { SOCK_UNLOCK(sp); soabort(sp); } else /* sp is now in sofree() */ SOCK_UNLOCK(sp); } } CURVNET_RESTORE(); return (error); } /* * soabort() is used to abruptly tear down a connection, such as when a * resource limit is reached (listen queue depth exceeded), or if a listen * socket is closed while there are sockets waiting to be accepted. * * This interface is tricky, because it is called on an unreferenced socket, * and must be called only by a thread that has actually removed the socket * from the listen queue it was on, or races with other threads are risked. * * This interface will call into the protocol code, so must not be called * with any socket locks held. Protocols do call it while holding their own * recursible protocol mutexes, but this is something that should be subject * to review in the future. */ void soabort(struct socket *so) { /* * In as much as is possible, assert that no references to this * socket are held. This is not quite the same as asserting that the * current thread is responsible for arranging for no references, but * is as close as we can get for now. */ KASSERT(so->so_count == 0, ("soabort: so_count")); KASSERT((so->so_state & SS_PROTOREF) == 0, ("soabort: SS_PROTOREF")); KASSERT(so->so_state & SS_NOFDREF, ("soabort: !SS_NOFDREF")); VNET_SO_ASSERT(so); if (so->so_proto->pr_usrreqs->pru_abort != NULL) (*so->so_proto->pr_usrreqs->pru_abort)(so); SOCK_LOCK(so); sofree(so); } int soaccept(struct socket *so, struct sockaddr **nam) { int error; SOCK_LOCK(so); KASSERT((so->so_state & SS_NOFDREF) != 0, ("soaccept: !NOFDREF")); so->so_state &= ~SS_NOFDREF; SOCK_UNLOCK(so); CURVNET_SET(so->so_vnet); error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam); CURVNET_RESTORE(); return (error); } int soconnect(struct socket *so, struct sockaddr *nam, struct thread *td) { return (soconnectat(AT_FDCWD, so, nam, td)); } int soconnectat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { int error; if (so->so_options & SO_ACCEPTCONN) return (EOPNOTSUPP); CURVNET_SET(so->so_vnet); /* * If protocol is connection-based, can only connect once. * Otherwise, if connected, try to disconnect first. This allows * user to disconnect by connecting to, e.g., a null address. */ if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && ((so->so_proto->pr_flags & PR_CONNREQUIRED) || (error = sodisconnect(so)))) { error = EISCONN; } else { /* * Prevent accumulated error from previous connection from * biting us. */ so->so_error = 0; if (fd == AT_FDCWD) { error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam, td); } else { error = (*so->so_proto->pr_usrreqs->pru_connectat)(fd, so, nam, td); } } CURVNET_RESTORE(); return (error); } int soconnect2(struct socket *so1, struct socket *so2) { int error; CURVNET_SET(so1->so_vnet); error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2); CURVNET_RESTORE(); return (error); } int sodisconnect(struct socket *so) { int error; if ((so->so_state & SS_ISCONNECTED) == 0) return (ENOTCONN); if (so->so_state & SS_ISDISCONNECTING) return (EALREADY); VNET_SO_ASSERT(so); error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so); return (error); } #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? 0 : SBL_WAIT) int sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { long space; ssize_t resid; int clen = 0, error, dontroute; KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM")); KASSERT(so->so_proto->pr_flags & PR_ATOMIC, ("sosend_dgram: !PR_ATOMIC")); if (uio != NULL) resid = uio->uio_resid; else resid = top->m_pkthdr.len; /* * In theory resid should be unsigned. However, space must be * signed, as it might be less than 0 if we over-committed, and we * must use a signed comparison of space and resid. On the other * hand, a negative resid causes us to loop sending 0-length * segments to the protocol. */ if (resid < 0) { error = EINVAL; goto out; } dontroute = (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0; if (td != NULL) td->td_ru.ru_msgsnd++; if (control != NULL) clen = control->m_len; SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_state & SBS_CANTSENDMORE) { SOCKBUF_UNLOCK(&so->so_snd); error = EPIPE; goto out; } if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto out; } if ((so->so_state & SS_ISCONNECTED) == 0) { /* * `sendto' and `sendmsg' is allowed on a connection-based * socket if it supports implied connect. Return ENOTCONN if * not connected and no address is supplied. */ if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { if ((so->so_state & SS_ISCONFIRMING) == 0 && !(resid == 0 && clen != 0)) { SOCKBUF_UNLOCK(&so->so_snd); error = ENOTCONN; goto out; } } else if (addr == NULL) { if (so->so_proto->pr_flags & PR_CONNREQUIRED) error = ENOTCONN; else error = EDESTADDRREQ; SOCKBUF_UNLOCK(&so->so_snd); goto out; } } /* * Do we need MSG_OOB support in SOCK_DGRAM? Signs here may be a * problem and need fixing. */ space = sbspace(&so->so_snd); if (flags & MSG_OOB) space += 1024; space -= clen; SOCKBUF_UNLOCK(&so->so_snd); if (resid > space) { error = EMSGSIZE; goto out; } if (uio == NULL) { resid = 0; if (flags & MSG_EOR) top->m_flags |= M_EOR; } else { /* * Copy the data from userland into a mbuf chain. * If no data is to be copied in, a single empty mbuf * is returned. */ top = m_uiotombuf(uio, M_WAITOK, space, max_hdr, (M_PKTHDR | ((flags & MSG_EOR) ? M_EOR : 0))); if (top == NULL) { error = EFAULT; /* only possible error */ goto out; } space -= resid - uio->uio_resid; resid = uio->uio_resid; } KASSERT(resid == 0, ("sosend_dgram: resid != 0")); /* * XXXRW: Frobbing SO_DONTROUTE here is even worse without sblock * than with. */ if (dontroute) { SOCK_LOCK(so); so->so_options |= SO_DONTROUTE; SOCK_UNLOCK(so); } /* * XXX all the SBS_CANTSENDMORE checks previously done could be out * of date. We could have received a reset packet in an interrupt or * maybe we slept while doing page faults in uiomove() etc. We could * probably recheck again inside the locking protection here, but * there are probably other places that this also happens. We must * rethink this. */ VNET_SO_ASSERT(so); error = (*so->so_proto->pr_usrreqs->pru_send)(so, (flags & MSG_OOB) ? PRUS_OOB : /* * If the user set MSG_EOF, the protocol understands this flag and * nothing left to send then use PRU_SEND_EOF instead of PRU_SEND. */ ((flags & MSG_EOF) && (so->so_proto->pr_flags & PR_IMPLOPCL) && (resid <= 0)) ? PRUS_EOF : /* If there is more to send set PRUS_MORETOCOME */ (flags & MSG_MORETOCOME) || (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0, top, addr, control, td); if (dontroute) { SOCK_LOCK(so); so->so_options &= ~SO_DONTROUTE; SOCK_UNLOCK(so); } clen = 0; control = NULL; top = NULL; out: if (top != NULL) m_freem(top); if (control != NULL) m_freem(control); return (error); } /* * Send on a socket. If send must go all at once and message is larger than * send buffering, then hard error. Lock against other senders. If must go * all at once and not enough room now, then inform user that this would * block and do nothing. Otherwise, if nonblocking, send as much as * possible. The data to be sent is described by "uio" if nonzero, otherwise * by the mbuf chain "top" (which must be null if uio is not). Data provided * in mbuf chain must be small enough to send all at once. * * Returns nonzero on error, timeout or signal; callers must check for short * counts if EINTR/ERESTART are returned. Data and control buffers are freed * on return. */ int sosend_generic(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { long space; ssize_t resid; int clen = 0, error, dontroute; int atomic = sosendallatonce(so) || top; int pru_flag; #ifdef KERN_TLS struct ktls_session *tls; int tls_enq_cnt, tls_pruflag; uint8_t tls_rtype; tls = NULL; tls_rtype = TLS_RLTYPE_APP; #endif if (uio != NULL) resid = uio->uio_resid; else if ((top->m_flags & M_PKTHDR) != 0) resid = top->m_pkthdr.len; else resid = m_length(top, NULL); /* * In theory resid should be unsigned. However, space must be * signed, as it might be less than 0 if we over-committed, and we * must use a signed comparison of space and resid. On the other * hand, a negative resid causes us to loop sending 0-length * segments to the protocol. * * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM * type sockets since that's an error. */ if (resid < 0 || (so->so_type == SOCK_STREAM && (flags & MSG_EOR))) { error = EINVAL; goto out; } dontroute = (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && (so->so_proto->pr_flags & PR_ATOMIC); if (td != NULL) td->td_ru.ru_msgsnd++; if (control != NULL) clen = control->m_len; error = sblock(&so->so_snd, SBLOCKWAIT(flags)); if (error) goto out; #ifdef KERN_TLS tls_pruflag = 0; tls = ktls_hold(so->so_snd.sb_tls_info); if (tls != NULL) { if (tls->mode == TCP_TLS_MODE_SW) tls_pruflag = PRUS_NOTREADY; if (control != NULL) { struct cmsghdr *cm = mtod(control, struct cmsghdr *); if (clen >= sizeof(*cm) && cm->cmsg_type == TLS_SET_RECORD_TYPE) { tls_rtype = *((uint8_t *)CMSG_DATA(cm)); clen = 0; m_freem(control); control = NULL; atomic = 1; } } } #endif restart: do { SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_state & SBS_CANTSENDMORE) { SOCKBUF_UNLOCK(&so->so_snd); error = EPIPE; goto release; } if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto release; } if ((so->so_state & SS_ISCONNECTED) == 0) { /* * `sendto' and `sendmsg' is allowed on a connection- * based socket if it supports implied connect. * Return ENOTCONN if not connected and no address is * supplied. */ if ((so->so_proto->pr_flags & PR_CONNREQUIRED) && (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) { if ((so->so_state & SS_ISCONFIRMING) == 0 && !(resid == 0 && clen != 0)) { SOCKBUF_UNLOCK(&so->so_snd); error = ENOTCONN; goto release; } } else if (addr == NULL) { SOCKBUF_UNLOCK(&so->so_snd); if (so->so_proto->pr_flags & PR_CONNREQUIRED) error = ENOTCONN; else 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) { SOCKBUF_UNLOCK(&so->so_snd); 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 | MSG_DONTWAIT)) != 0) { SOCKBUF_UNLOCK(&so->so_snd); error = EWOULDBLOCK; goto release; } error = sbwait(&so->so_snd); SOCKBUF_UNLOCK(&so->so_snd); if (error) goto release; goto restart; } SOCKBUF_UNLOCK(&so->so_snd); space -= clen; do { if (uio == NULL) { resid = 0; if (flags & MSG_EOR) top->m_flags |= M_EOR; #ifdef KERN_TLS if (tls != NULL) { ktls_frame(top, tls, &tls_enq_cnt, tls_rtype); tls_rtype = TLS_RLTYPE_APP; } #endif } else { /* * Copy the data from userland into a mbuf * chain. If resid is 0, which can happen * only if we have control to send, then * a single empty mbuf is returned. This * is a workaround to prevent protocol send * methods to panic. */ #ifdef KERN_TLS if (tls != NULL) { top = m_uiotombuf(uio, M_WAITOK, space, tls->params.max_frame_len, M_EXTPG | ((flags & MSG_EOR) ? M_EOR : 0)); if (top != NULL) { ktls_frame(top, tls, &tls_enq_cnt, tls_rtype); } tls_rtype = TLS_RLTYPE_APP; } else #endif top = m_uiotombuf(uio, M_WAITOK, space, (atomic ? max_hdr : 0), (atomic ? M_PKTHDR : 0) | ((flags & MSG_EOR) ? M_EOR : 0)); if (top == NULL) { error = EFAULT; /* only possible error */ goto release; } space -= resid - uio->uio_resid; resid = uio->uio_resid; } if (dontroute) { SOCK_LOCK(so); so->so_options |= SO_DONTROUTE; SOCK_UNLOCK(so); } /* * XXX all the SBS_CANTSENDMORE checks previously * done could be out of date. We could have received * a reset packet in an interrupt or maybe we slept * while doing page faults in uiomove() etc. We * could probably recheck again inside the locking * protection here, but there are probably other * places that this also happens. We must rethink * this. */ VNET_SO_ASSERT(so); pru_flag = (flags & MSG_OOB) ? PRUS_OOB : /* * If the user set MSG_EOF, the protocol understands * this flag and nothing left to send then use * PRU_SEND_EOF instead of PRU_SEND. */ ((flags & MSG_EOF) && (so->so_proto->pr_flags & PR_IMPLOPCL) && (resid <= 0)) ? PRUS_EOF : /* If there is more to send set PRUS_MORETOCOME. */ (flags & MSG_MORETOCOME) || (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0; #ifdef KERN_TLS pru_flag |= tls_pruflag; #endif error = (*so->so_proto->pr_usrreqs->pru_send)(so, pru_flag, top, addr, control, td); if (dontroute) { SOCK_LOCK(so); so->so_options &= ~SO_DONTROUTE; SOCK_UNLOCK(so); } #ifdef KERN_TLS if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) { - /* - * Note that error is intentionally - * ignored. - * - * Like sendfile(), we rely on the - * completion routine (pru_ready()) - * to free the mbufs in the event that - * pru_send() encountered an error and - * did not append them to the sockbuf. - */ - soref(so); - ktls_enqueue(top, so, tls_enq_cnt); + if (error != 0) { + m_freem(top); + top = NULL; + } else { + soref(so); + ktls_enqueue(top, so, tls_enq_cnt); + } } #endif clen = 0; control = NULL; top = NULL; if (error) goto release; } while (resid && space > 0); } while (resid); release: sbunlock(&so->so_snd); out: #ifdef KERN_TLS if (tls != NULL) ktls_free(tls); #endif if (top != NULL) m_freem(top); if (control != NULL) m_freem(control); return (error); } int sosend(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { int error; CURVNET_SET(so->so_vnet); if (!SOLISTENING(so)) error = so->so_proto->pr_usrreqs->pru_sosend(so, addr, uio, top, control, flags, td); else { m_freem(top); m_freem(control); error = ENOTCONN; } CURVNET_RESTORE(); return (error); } /* * The part of soreceive() that implements reading non-inline out-of-band * data from a socket. For more complete comments, see soreceive(), from * which this code originated. * * Note that soreceive_rcvoob(), unlike the remainder of soreceive(), is * unable to return an mbuf chain to the caller. */ static int soreceive_rcvoob(struct socket *so, struct uio *uio, int flags) { struct protosw *pr = so->so_proto; struct mbuf *m; int error; KASSERT(flags & MSG_OOB, ("soreceive_rcvoob: (flags & MSG_OOB) == 0")); VNET_SO_ASSERT(so); m = m_get(M_WAITOK, MT_DATA); error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK); if (error) goto bad; do { error = uiomove(mtod(m, void *), (int) min(uio->uio_resid, m->m_len), uio); m = m_free(m); } while (uio->uio_resid && error == 0 && m); bad: if (m != NULL) m_freem(m); return (error); } /* * Following replacement or removal of the first mbuf on the first mbuf chain * of a socket buffer, push necessary state changes back into the socket * buffer so that other consumers see the values consistently. 'nextrecord' * is the callers locally stored value of the original value of * sb->sb_mb->m_nextpkt which must be restored when the lead mbuf changes. * NOTE: 'nextrecord' may be NULL. */ static __inline void sockbuf_pushsync(struct sockbuf *sb, struct mbuf *nextrecord) { SOCKBUF_LOCK_ASSERT(sb); /* * First, update for the new value of nextrecord. If necessary, make * it the first record. */ if (sb->sb_mb != NULL) sb->sb_mb->m_nextpkt = nextrecord; else sb->sb_mb = nextrecord; /* * Now update any dependent socket buffer fields to reflect the new * state. This is an expanded inline of SB_EMPTY_FIXUP(), with the * addition of a second clause that takes care of the case where * sb_mb has been updated, but remains the last record. */ if (sb->sb_mb == NULL) { sb->sb_mbtail = NULL; sb->sb_lastrecord = NULL; } else if (sb->sb_mb->m_nextpkt == NULL) sb->sb_lastrecord = sb->sb_mb; } /* * Implement receive operations on a socket. We depend on the way that * records are added to the sockbuf by sbappend. In particular, each record * (mbufs linked through m_next) must begin with an address if the protocol * so specifies, followed by an optional mbuf or mbufs containing ancillary * data, and then zero or more mbufs of data. In order to allow parallelism * between network receive and copying to user space, as well as avoid * sleeping with a mutex held, we release the socket buffer mutex during the * user space copy. Although the sockbuf is locked, new data may still be * appended, and thus we must maintain consistency of the sockbuf during that * time. * * The caller may receive the data as a single mbuf chain by supplying an * mbuf **mp0 for use in returning the chain. The uio is then used only for * the count in uio_resid. */ int soreceive_generic(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { struct mbuf *m, **mp; int flags, error, offset; ssize_t len; struct protosw *pr = so->so_proto; struct mbuf *nextrecord; int moff, type = 0; ssize_t orig_resid = uio->uio_resid; mp = mp0; if (psa != NULL) *psa = NULL; if (controlp != NULL) *controlp = NULL; if (flagsp != NULL) flags = *flagsp &~ MSG_EOR; else flags = 0; if (flags & MSG_OOB) return (soreceive_rcvoob(so, uio, flags)); if (mp != NULL) *mp = NULL; if ((pr->pr_flags & PR_WANTRCVD) && (so->so_state & SS_ISCONFIRMING) && uio->uio_resid) { VNET_SO_ASSERT(so); (*pr->pr_usrreqs->pru_rcvd)(so, 0); } error = sblock(&so->so_rcv, SBLOCKWAIT(flags)); if (error) return (error); restart: SOCKBUF_LOCK(&so->so_rcv); m = so->so_rcv.sb_mb; /* * If we have less data than requested, block awaiting more (subject * to any timeout) if: * 1. the current count is less than the low water mark, or * 2. MSG_DONTWAIT is not set */ if (m == NULL || (((flags & MSG_DONTWAIT) == 0 && sbavail(&so->so_rcv) < uio->uio_resid) && sbavail(&so->so_rcv) < so->so_rcv.sb_lowat && m->m_nextpkt == NULL && (pr->pr_flags & PR_ATOMIC) == 0)) { KASSERT(m != NULL || !sbavail(&so->so_rcv), ("receive: m == %p sbavail == %u", m, sbavail(&so->so_rcv))); if (so->so_error) { if (m != NULL) goto dontblock; error = so->so_error; if ((flags & MSG_PEEK) == 0) so->so_error = 0; SOCKBUF_UNLOCK(&so->so_rcv); goto release; } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { if (m != NULL) goto dontblock; #ifdef KERN_TLS else if (so->so_rcv.sb_tlsdcc == 0 && so->so_rcv.sb_tlscc == 0) { #else else { #endif SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } for (; m != NULL; m = m->m_next) if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { m = so->so_rcv.sb_mb; goto dontblock; } if ((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING | SS_ISDISCONNECTED)) == 0 && (so->so_proto->pr_flags & PR_CONNREQUIRED) != 0) { SOCKBUF_UNLOCK(&so->so_rcv); error = ENOTCONN; goto release; } if (uio->uio_resid == 0) { SOCKBUF_UNLOCK(&so->so_rcv); goto release; } if ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO))) { SOCKBUF_UNLOCK(&so->so_rcv); error = EWOULDBLOCK; goto release; } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); error = sbwait(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); if (error) goto release; goto restart; } dontblock: /* * From this point onward, we maintain 'nextrecord' as a cache of the * pointer to the next record in the socket buffer. We must keep the * various socket buffer pointers and local stack versions of the * pointers in sync, pushing out modifications before dropping the * socket buffer mutex, and re-reading them when picking it up. * * Otherwise, we will race with the network stack appending new data * or records onto the socket buffer by using inconsistent/stale * versions of the field, possibly resulting in socket buffer * corruption. * * By holding the high-level sblock(), we prevent simultaneous * readers from pulling off the front of the socket buffer. */ SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; KASSERT(m == so->so_rcv.sb_mb, ("soreceive: m != so->so_rcv.sb_mb")); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); nextrecord = m->m_nextpkt; if (pr->pr_flags & PR_ADDR) { KASSERT(m->m_type == MT_SONAME, ("m->m_type == %d", m->m_type)); orig_resid = 0; if (psa != NULL) *psa = sodupsockaddr(mtod(m, struct sockaddr *), M_NOWAIT); if (flags & MSG_PEEK) { m = m->m_next; } else { sbfree(&so->so_rcv, m); so->so_rcv.sb_mb = m_free(m); m = so->so_rcv.sb_mb; sockbuf_pushsync(&so->so_rcv, nextrecord); } } /* * Process one or more MT_CONTROL mbufs present before any data mbufs * in the first mbuf chain on the socket buffer. If MSG_PEEK, we * just copy the data; if !MSG_PEEK, we call into the protocol to * perform externalization (or freeing if controlp == NULL). */ if (m != NULL && m->m_type == MT_CONTROL) { struct mbuf *cm = NULL, *cmn; struct mbuf **cme = &cm; #ifdef KERN_TLS struct cmsghdr *cmsg; struct tls_get_record tgr; /* * For MSG_TLSAPPDATA, check for a non-application data * record. If found, return ENXIO without removing * it from the receive queue. This allows a subsequent * call without MSG_TLSAPPDATA to receive it. * Note that, for TLS, there should only be a single * control mbuf with the TLS_GET_RECORD message in it. */ if (flags & MSG_TLSAPPDATA) { cmsg = mtod(m, struct cmsghdr *); if (cmsg->cmsg_type == TLS_GET_RECORD && cmsg->cmsg_len == CMSG_LEN(sizeof(tgr))) { memcpy(&tgr, CMSG_DATA(cmsg), sizeof(tgr)); /* This will need to change for TLS 1.3. */ if (tgr.tls_type != TLS_RLTYPE_APP) { SOCKBUF_UNLOCK(&so->so_rcv); error = ENXIO; goto release; } } } #endif do { if (flags & MSG_PEEK) { if (controlp != NULL) { *controlp = m_copym(m, 0, m->m_len, M_NOWAIT); controlp = &(*controlp)->m_next; } m = m->m_next; } else { sbfree(&so->so_rcv, m); so->so_rcv.sb_mb = m->m_next; m->m_next = NULL; *cme = m; cme = &(*cme)->m_next; m = so->so_rcv.sb_mb; } } while (m != NULL && m->m_type == MT_CONTROL); if ((flags & MSG_PEEK) == 0) sockbuf_pushsync(&so->so_rcv, nextrecord); while (cm != NULL) { cmn = cm->m_next; cm->m_next = NULL; if (pr->pr_domain->dom_externalize != NULL) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); error = (*pr->pr_domain->dom_externalize) (cm, controlp, flags); SOCKBUF_LOCK(&so->so_rcv); } else if (controlp != NULL) *controlp = cm; else m_freem(cm); if (controlp != NULL) { orig_resid = 0; while (*controlp != NULL) controlp = &(*controlp)->m_next; } cm = cmn; } if (m != NULL) nextrecord = so->so_rcv.sb_mb->m_nextpkt; else nextrecord = so->so_rcv.sb_mb; orig_resid = 0; } if (m != NULL) { if ((flags & MSG_PEEK) == 0) { KASSERT(m->m_nextpkt == nextrecord, ("soreceive: post-control, nextrecord !sync")); if (nextrecord == NULL) { KASSERT(so->so_rcv.sb_mb == m, ("soreceive: post-control, sb_mb!=m")); KASSERT(so->so_rcv.sb_lastrecord == m, ("soreceive: post-control, lastrecord!=m")); } } type = m->m_type; if (type == MT_OOBDATA) flags |= MSG_OOB; } else { if ((flags & MSG_PEEK) == 0) { KASSERT(so->so_rcv.sb_mb == nextrecord, ("soreceive: sb_mb != nextrecord")); if (so->so_rcv.sb_mb == NULL) { KASSERT(so->so_rcv.sb_lastrecord == NULL, ("soreceive: sb_lastercord != NULL")); } } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * Now continue to read any data mbufs off of the head of the socket * buffer until the read request is satisfied. Note that 'type' is * used to store the type of any mbuf reads that have happened so far * such that soreceive() can stop reading if the type changes, which * causes soreceive() to return only one of regular data and inline * out-of-band data in a single socket receive operation. */ moff = 0; offset = 0; while (m != NULL && !(m->m_flags & M_NOTAVAIL) && uio->uio_resid > 0 && error == 0) { /* * If the type of mbuf has changed since the last mbuf * examined ('type'), end the receive operation. */ SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (m->m_type == MT_OOBDATA || m->m_type == MT_CONTROL) { if (type != m->m_type) break; } else if (type == MT_OOBDATA) break; else KASSERT(m->m_type == MT_DATA, ("m->m_type == %d", m->m_type)); so->so_rcv.sb_state &= ~SBS_RCVATMARK; len = uio->uio_resid; if (so->so_oobmark && len > so->so_oobmark - offset) len = so->so_oobmark - offset; if (len > m->m_len - moff) len = m->m_len - moff; /* * If mp is set, just pass back the mbufs. Otherwise copy * them out via the uio, then free. Sockbuf must be * consistent here (points to current mbuf, it points to next * record) when we drop priority; we must note any additions * to the sockbuf when we block interrupts again. */ if (mp == NULL) { SOCKBUF_LOCK_ASSERT(&so->so_rcv); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); if ((m->m_flags & M_EXTPG) != 0) error = m_unmappedtouio(m, moff, uio, (int)len); else error = uiomove(mtod(m, char *) + moff, (int)len, uio); SOCKBUF_LOCK(&so->so_rcv); if (error) { /* * The MT_SONAME mbuf has already been removed * from the record, so it is necessary to * remove the data mbufs, if any, to preserve * the invariant in the case of PR_ADDR that * requires MT_SONAME mbufs at the head of * each record. */ if (pr->pr_flags & PR_ATOMIC && ((flags & MSG_PEEK) == 0)) (void)sbdroprecord_locked(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } else uio->uio_resid -= len; SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (len == m->m_len - moff) { if (m->m_flags & M_EOR) flags |= MSG_EOR; if (flags & MSG_PEEK) { m = m->m_next; moff = 0; } else { nextrecord = m->m_nextpkt; sbfree(&so->so_rcv, m); if (mp != NULL) { m->m_nextpkt = NULL; *mp = m; mp = &m->m_next; so->so_rcv.sb_mb = m = m->m_next; *mp = NULL; } else { so->so_rcv.sb_mb = m_free(m); m = so->so_rcv.sb_mb; } sockbuf_pushsync(&so->so_rcv, nextrecord); SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); } } else { if (flags & MSG_PEEK) moff += len; else { if (mp != NULL) { if (flags & MSG_DONTWAIT) { *mp = m_copym(m, 0, len, M_NOWAIT); if (*mp == NULL) { /* * m_copym() couldn't * allocate an mbuf. * Adjust uio_resid back * (it was adjusted * down by len bytes, * which we didn't end * up "copying" over). */ uio->uio_resid += len; break; } } else { SOCKBUF_UNLOCK(&so->so_rcv); *mp = m_copym(m, 0, len, M_WAITOK); SOCKBUF_LOCK(&so->so_rcv); } } sbcut_locked(&so->so_rcv, len); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_oobmark) { if ((flags & MSG_PEEK) == 0) { so->so_oobmark -= len; if (so->so_oobmark == 0) { so->so_rcv.sb_state |= SBS_RCVATMARK; break; } } else { offset += len; if (offset == so->so_oobmark) break; } } if (flags & MSG_EOR) break; /* * If the MSG_WAITALL flag is set (for non-atomic socket), we * must not quit until "uio->uio_resid == 0" or an error * termination. If a signal/timeout occurs, return with a * short count but without error. Keep sockbuf locked * against other readers. */ while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && !sosendallatonce(so) && nextrecord == NULL) { SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (so->so_error || so->so_rcv.sb_state & SBS_CANTRCVMORE) break; /* * Notify the protocol that some data has been * drained before blocking. */ if (pr->pr_flags & PR_WANTRCVD) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); (*pr->pr_usrreqs->pru_rcvd)(so, flags); SOCKBUF_LOCK(&so->so_rcv); } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * We could receive some data while was notifying * the protocol. Skip blocking in this case. */ if (so->so_rcv.sb_mb == NULL) { error = sbwait(&so->so_rcv); if (error) { SOCKBUF_UNLOCK(&so->so_rcv); goto release; } } m = so->so_rcv.sb_mb; if (m != NULL) nextrecord = m->m_nextpkt; } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (m != NULL && pr->pr_flags & PR_ATOMIC) { flags |= MSG_TRUNC; if ((flags & MSG_PEEK) == 0) (void) sbdroprecord_locked(&so->so_rcv); } if ((flags & MSG_PEEK) == 0) { if (m == NULL) { /* * First part is an inline SB_EMPTY_FIXUP(). Second * part makes sure sb_lastrecord is up-to-date if * there is still data in the socket buffer. */ so->so_rcv.sb_mb = nextrecord; if (so->so_rcv.sb_mb == NULL) { so->so_rcv.sb_mbtail = NULL; so->so_rcv.sb_lastrecord = NULL; } else if (nextrecord->m_nextpkt == NULL) so->so_rcv.sb_lastrecord = nextrecord; } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); /* * If soreceive() is being done from the socket callback, * then don't need to generate ACK to peer to update window, * since ACK will be generated on return to TCP. */ if (!(flags & MSG_SOCALLBCK) && (pr->pr_flags & PR_WANTRCVD)) { SOCKBUF_UNLOCK(&so->so_rcv); VNET_SO_ASSERT(so); (*pr->pr_usrreqs->pru_rcvd)(so, flags); SOCKBUF_LOCK(&so->so_rcv); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (orig_resid == uio->uio_resid && orig_resid && (flags & MSG_EOR) == 0 && (so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0) { SOCKBUF_UNLOCK(&so->so_rcv); goto restart; } SOCKBUF_UNLOCK(&so->so_rcv); if (flagsp != NULL) *flagsp |= flags; release: sbunlock(&so->so_rcv); return (error); } /* * Optimized version of soreceive() for stream (TCP) sockets. */ int soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { int len = 0, error = 0, flags, oresid; struct sockbuf *sb; struct mbuf *m, *n = NULL; /* We only do stream sockets. */ if (so->so_type != SOCK_STREAM) return (EINVAL); if (psa != NULL) *psa = NULL; if (flagsp != NULL) flags = *flagsp &~ MSG_EOR; else flags = 0; if (controlp != NULL) *controlp = NULL; if (flags & MSG_OOB) return (soreceive_rcvoob(so, uio, flags)); if (mp0 != NULL) *mp0 = NULL; sb = &so->so_rcv; #ifdef KERN_TLS /* * KTLS store TLS records as records with a control message to * describe the framing. * * We check once here before acquiring locks to optimize the * common case. */ if (sb->sb_tls_info != NULL) return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); #endif /* Prevent other readers from entering the socket. */ error = sblock(sb, SBLOCKWAIT(flags)); if (error) return (error); SOCKBUF_LOCK(sb); #ifdef KERN_TLS if (sb->sb_tls_info != NULL) { SOCKBUF_UNLOCK(sb); sbunlock(sb); return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); } #endif /* Easy one, no space to copyout anything. */ if (uio->uio_resid == 0) { error = EINVAL; goto out; } oresid = uio->uio_resid; /* We will never ever get anything unless we are or were connected. */ if (!(so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED))) { error = ENOTCONN; goto out; } restart: SOCKBUF_LOCK_ASSERT(&so->so_rcv); /* Abort if socket has reported problems. */ if (so->so_error) { if (sbavail(sb) > 0) goto deliver; if (oresid > uio->uio_resid) goto out; error = so->so_error; if (!(flags & MSG_PEEK)) so->so_error = 0; goto out; } /* Door is closed. Deliver what is left, if any. */ if (sb->sb_state & SBS_CANTRCVMORE) { if (sbavail(sb) > 0) goto deliver; else goto out; } /* Socket buffer is empty and we shall not block. */ if (sbavail(sb) == 0 && ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)))) { error = EAGAIN; goto out; } /* Socket buffer got some data that we shall deliver now. */ if (sbavail(sb) > 0 && !(flags & MSG_WAITALL) && ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO)) || sbavail(sb) >= sb->sb_lowat || sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat) ) { goto deliver; } /* On MSG_WAITALL we must wait until all data or error arrives. */ if ((flags & MSG_WAITALL) && (sbavail(sb) >= uio->uio_resid || sbavail(sb) >= sb->sb_hiwat)) goto deliver; /* * Wait and block until (more) data comes in. * NB: Drops the sockbuf lock during wait. */ error = sbwait(sb); if (error) goto out; goto restart; deliver: SOCKBUF_LOCK_ASSERT(&so->so_rcv); KASSERT(sbavail(sb) > 0, ("%s: sockbuf empty", __func__)); KASSERT(sb->sb_mb != NULL, ("%s: sb_mb == NULL", __func__)); /* Statistics. */ if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; /* Fill uio until full or current end of socket buffer is reached. */ len = min(uio->uio_resid, sbavail(sb)); if (mp0 != NULL) { /* Dequeue as many mbufs as possible. */ if (!(flags & MSG_PEEK) && len >= sb->sb_mb->m_len) { if (*mp0 == NULL) *mp0 = sb->sb_mb; else m_cat(*mp0, sb->sb_mb); for (m = sb->sb_mb; m != NULL && m->m_len <= len; m = m->m_next) { KASSERT(!(m->m_flags & M_NOTAVAIL), ("%s: m %p not available", __func__, m)); len -= m->m_len; uio->uio_resid -= m->m_len; sbfree(sb, m); n = m; } n->m_next = NULL; sb->sb_mb = m; sb->sb_lastrecord = sb->sb_mb; if (sb->sb_mb == NULL) SB_EMPTY_FIXUP(sb); } /* Copy the remainder. */ if (len > 0) { KASSERT(sb->sb_mb != NULL, ("%s: len > 0 && sb->sb_mb empty", __func__)); m = m_copym(sb->sb_mb, 0, len, M_NOWAIT); if (m == NULL) len = 0; /* Don't flush data from sockbuf. */ else uio->uio_resid -= len; if (*mp0 != NULL) m_cat(*mp0, m); else *mp0 = m; if (*mp0 == NULL) { error = ENOBUFS; goto out; } } } else { /* NB: Must unlock socket buffer as uiomove may sleep. */ SOCKBUF_UNLOCK(sb); error = m_mbuftouio(uio, sb->sb_mb, len); SOCKBUF_LOCK(sb); if (error) goto out; } SBLASTRECORDCHK(sb); SBLASTMBUFCHK(sb); /* * Remove the delivered data from the socket buffer unless we * were only peeking. */ if (!(flags & MSG_PEEK)) { if (len > 0) sbdrop_locked(sb, len); /* Notify protocol that we drained some data. */ if ((so->so_proto->pr_flags & PR_WANTRCVD) && (((flags & MSG_WAITALL) && uio->uio_resid > 0) || !(flags & MSG_SOCALLBCK))) { SOCKBUF_UNLOCK(sb); VNET_SO_ASSERT(so); (*so->so_proto->pr_usrreqs->pru_rcvd)(so, flags); SOCKBUF_LOCK(sb); } } /* * For MSG_WAITALL we may have to loop again and wait for * more data to come in. */ if ((flags & MSG_WAITALL) && uio->uio_resid > 0) goto restart; out: SOCKBUF_LOCK_ASSERT(sb); SBLASTRECORDCHK(sb); SBLASTMBUFCHK(sb); SOCKBUF_UNLOCK(sb); sbunlock(sb); return (error); } /* * Optimized version of soreceive() for simple datagram cases from userspace. * Unlike in the stream case, we're able to drop a datagram if copyout() * fails, and because we handle datagrams atomically, we don't need to use a * sleep lock to prevent I/O interlacing. */ int soreceive_dgram(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { struct mbuf *m, *m2; int flags, error; ssize_t len; struct protosw *pr = so->so_proto; struct mbuf *nextrecord; if (psa != NULL) *psa = NULL; if (controlp != NULL) *controlp = NULL; if (flagsp != NULL) flags = *flagsp &~ MSG_EOR; else flags = 0; /* * For any complicated cases, fall back to the full * soreceive_generic(). */ if (mp0 != NULL || (flags & MSG_PEEK) || (flags & MSG_OOB)) return (soreceive_generic(so, psa, uio, mp0, controlp, flagsp)); /* * Enforce restrictions on use. */ KASSERT((pr->pr_flags & PR_WANTRCVD) == 0, ("soreceive_dgram: wantrcvd")); KASSERT(pr->pr_flags & PR_ATOMIC, ("soreceive_dgram: !atomic")); KASSERT((so->so_rcv.sb_state & SBS_RCVATMARK) == 0, ("soreceive_dgram: SBS_RCVATMARK")); KASSERT((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0, ("soreceive_dgram: P_CONNREQUIRED")); /* * Loop blocking while waiting for a datagram. */ SOCKBUF_LOCK(&so->so_rcv); while ((m = so->so_rcv.sb_mb) == NULL) { KASSERT(sbavail(&so->so_rcv) == 0, ("soreceive_dgram: sb_mb NULL but sbavail %u", sbavail(&so->so_rcv))); if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_rcv); return (error); } if (so->so_rcv.sb_state & SBS_CANTRCVMORE || uio->uio_resid == 0) { SOCKBUF_UNLOCK(&so->so_rcv); return (0); } if ((so->so_state & SS_NBIO) || (flags & (MSG_DONTWAIT|MSG_NBIO))) { SOCKBUF_UNLOCK(&so->so_rcv); return (EWOULDBLOCK); } SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); error = sbwait(&so->so_rcv); if (error) { SOCKBUF_UNLOCK(&so->so_rcv); return (error); } } SOCKBUF_LOCK_ASSERT(&so->so_rcv); if (uio->uio_td) uio->uio_td->td_ru.ru_msgrcv++; SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); nextrecord = m->m_nextpkt; if (nextrecord == NULL) { KASSERT(so->so_rcv.sb_lastrecord == m, ("soreceive_dgram: lastrecord != m")); } KASSERT(so->so_rcv.sb_mb->m_nextpkt == nextrecord, ("soreceive_dgram: m_nextpkt != nextrecord")); /* * Pull 'm' and its chain off the front of the packet queue. */ so->so_rcv.sb_mb = NULL; sockbuf_pushsync(&so->so_rcv, nextrecord); /* * Walk 'm's chain and free that many bytes from the socket buffer. */ for (m2 = m; m2 != NULL; m2 = m2->m_next) sbfree(&so->so_rcv, m2); /* * Do a few last checks before we let go of the lock. */ SBLASTRECORDCHK(&so->so_rcv); SBLASTMBUFCHK(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_rcv); if (pr->pr_flags & PR_ADDR) { KASSERT(m->m_type == MT_SONAME, ("m->m_type == %d", m->m_type)); if (psa != NULL) *psa = sodupsockaddr(mtod(m, struct sockaddr *), M_NOWAIT); m = m_free(m); } if (m == NULL) { /* XXXRW: Can this happen? */ return (0); } /* * Packet to copyout() is now in 'm' and it is disconnected from the * queue. * * Process one or more MT_CONTROL mbufs present before any data mbufs * in the first mbuf chain on the socket buffer. We call into the * protocol to perform externalization (or freeing if controlp == * NULL). In some cases there can be only MT_CONTROL mbufs without * MT_DATA mbufs. */ if (m->m_type == MT_CONTROL) { struct mbuf *cm = NULL, *cmn; struct mbuf **cme = &cm; do { m2 = m->m_next; m->m_next = NULL; *cme = m; cme = &(*cme)->m_next; m = m2; } while (m != NULL && m->m_type == MT_CONTROL); while (cm != NULL) { cmn = cm->m_next; cm->m_next = NULL; if (pr->pr_domain->dom_externalize != NULL) { error = (*pr->pr_domain->dom_externalize) (cm, controlp, flags); } else if (controlp != NULL) *controlp = cm; else m_freem(cm); if (controlp != NULL) { while (*controlp != NULL) controlp = &(*controlp)->m_next; } cm = cmn; } } KASSERT(m == NULL || m->m_type == MT_DATA, ("soreceive_dgram: !data")); while (m != NULL && uio->uio_resid > 0) { len = uio->uio_resid; if (len > m->m_len) len = m->m_len; error = uiomove(mtod(m, char *), (int)len, uio); if (error) { m_freem(m); return (error); } if (len == m->m_len) m = m_free(m); else { m->m_data += len; m->m_len -= len; } } if (m != NULL) { flags |= MSG_TRUNC; m_freem(m); } if (flagsp != NULL) *flagsp |= flags; return (0); } int soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { int error; CURVNET_SET(so->so_vnet); if (!SOLISTENING(so)) error = (so->so_proto->pr_usrreqs->pru_soreceive(so, psa, uio, mp0, controlp, flagsp)); else error = ENOTCONN; CURVNET_RESTORE(); return (error); } int soshutdown(struct socket *so, int how) { struct protosw *pr = so->so_proto; int error, soerror_enotconn; if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) return (EINVAL); soerror_enotconn = 0; if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) { /* * POSIX mandates us to return ENOTCONN when shutdown(2) is * invoked on a datagram sockets, however historically we would * actually tear socket down. This is known to be leveraged by * some applications to unblock process waiting in recvXXX(2) * by other process that it shares that socket with. Try to meet * both backward-compatibility and POSIX requirements by forcing * ENOTCONN but still asking protocol to perform pru_shutdown(). */ if (so->so_type != SOCK_DGRAM && !SOLISTENING(so)) return (ENOTCONN); soerror_enotconn = 1; } if (SOLISTENING(so)) { if (how != SHUT_WR) { SOLISTEN_LOCK(so); so->so_error = ECONNABORTED; solisten_wakeup(so); /* unlocks so */ } goto done; } CURVNET_SET(so->so_vnet); if (pr->pr_usrreqs->pru_flush != NULL) (*pr->pr_usrreqs->pru_flush)(so, how); if (how != SHUT_WR) sorflush(so); if (how != SHUT_RD) { error = (*pr->pr_usrreqs->pru_shutdown)(so); wakeup(&so->so_timeo); CURVNET_RESTORE(); return ((error == 0 && soerror_enotconn) ? ENOTCONN : error); } wakeup(&so->so_timeo); CURVNET_RESTORE(); done: return (soerror_enotconn ? ENOTCONN : 0); } void sorflush(struct socket *so) { struct sockbuf *sb = &so->so_rcv; struct protosw *pr = so->so_proto; struct socket aso; VNET_SO_ASSERT(so); /* * In order to avoid calling dom_dispose with the socket buffer mutex * held, and in order to generally avoid holding the lock for a long * time, we make a copy of the socket buffer and clear the original * (except locks, state). The new socket buffer copy won't have * initialized locks so we can only call routines that won't use or * assert those locks. * * Dislodge threads currently blocked in receive and wait to acquire * a lock against other simultaneous readers before clearing the * socket buffer. Don't let our acquire be interrupted by a signal * despite any existing socket disposition on interruptable waiting. */ socantrcvmore(so); (void) sblock(sb, SBL_WAIT | SBL_NOINTR); /* * Invalidate/clear most of the sockbuf structure, but leave selinfo * and mutex data unchanged. */ SOCKBUF_LOCK(sb); bzero(&aso, sizeof(aso)); aso.so_pcb = so->so_pcb; bcopy(&sb->sb_startzero, &aso.so_rcv.sb_startzero, sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); bzero(&sb->sb_startzero, sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); SOCKBUF_UNLOCK(sb); sbunlock(sb); /* * Dispose of special rights and flush the copied socket. Don't call * any unsafe routines (that rely on locks being initialized) on aso. */ if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose != NULL) (*pr->pr_domain->dom_dispose)(&aso); sbrelease_internal(&aso.so_rcv, so); } /* * Wrapper for Socket established helper hook. * Parameters: socket, context of the hook point, hook id. */ static int inline hhook_run_socket(struct socket *so, void *hctx, int32_t h_id) { struct socket_hhook_data hhook_data = { .so = so, .hctx = hctx, .m = NULL, .status = 0 }; CURVNET_SET(so->so_vnet); HHOOKS_RUN_IF(V_socket_hhh[h_id], &hhook_data, &so->osd); CURVNET_RESTORE(); /* Ugly but needed, since hhooks return void for now */ return (hhook_data.status); } /* * Perhaps this routine, and sooptcopyout(), below, ought to come in an * additional variant to handle the case where the option value needs to be * some kind of integer, but not a specific size. In addition to their use * here, these functions are also called by the protocol-level pr_ctloutput() * routines. */ int sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen) { size_t valsize; /* * If the user gives us more than we wanted, we ignore it, but if we * don't get the minimum length the caller wants, we return EINVAL. * On success, sopt->sopt_valsize is set to however much we actually * retrieved. */ if ((valsize = sopt->sopt_valsize) < minlen) return EINVAL; if (valsize > len) sopt->sopt_valsize = valsize = len; if (sopt->sopt_td != NULL) return (copyin(sopt->sopt_val, buf, valsize)); bcopy(sopt->sopt_val, buf, valsize); return (0); } /* * Kernel version of setsockopt(2). * * XXX: optlen is size_t, not socklen_t */ int so_setsockopt(struct socket *so, int level, int optname, void *optval, size_t optlen) { struct sockopt sopt; sopt.sopt_level = level; sopt.sopt_name = optname; sopt.sopt_dir = SOPT_SET; sopt.sopt_val = optval; sopt.sopt_valsize = optlen; sopt.sopt_td = NULL; return (sosetopt(so, &sopt)); } int sosetopt(struct socket *so, struct sockopt *sopt) { int error, optval; struct linger l; struct timeval tv; sbintime_t val; uint32_t val32; #ifdef MAC struct mac extmac; #endif CURVNET_SET(so->so_vnet); error = 0; if (sopt->sopt_level != SOL_SOCKET) { if (so->so_proto->pr_ctloutput != NULL) error = (*so->so_proto->pr_ctloutput)(so, sopt); else error = ENOPROTOOPT; } else { switch (sopt->sopt_name) { case SO_ACCEPTFILTER: error = accept_filt_setopt(so, sopt); if (error) goto bad; break; case SO_LINGER: error = sooptcopyin(sopt, &l, sizeof l, sizeof l); if (error) goto bad; if (l.l_linger < 0 || l.l_linger > USHRT_MAX || l.l_linger > (INT_MAX / hz)) { error = EDOM; goto bad; } SOCK_LOCK(so); so->so_linger = l.l_linger; if (l.l_onoff) so->so_options |= SO_LINGER; else so->so_options &= ~SO_LINGER; SOCK_UNLOCK(so); break; case SO_DEBUG: case SO_KEEPALIVE: case SO_DONTROUTE: case SO_USELOOPBACK: case SO_BROADCAST: case SO_REUSEADDR: case SO_REUSEPORT: case SO_REUSEPORT_LB: case SO_OOBINLINE: case SO_TIMESTAMP: case SO_BINTIME: case SO_NOSIGPIPE: case SO_NO_DDP: case SO_NO_OFFLOAD: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; SOCK_LOCK(so); if (optval) so->so_options |= sopt->sopt_name; else so->so_options &= ~sopt->sopt_name; SOCK_UNLOCK(so); break; case SO_SETFIB: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; if (optval < 0 || optval >= rt_numfibs) { error = EINVAL; goto bad; } if (((so->so_proto->pr_domain->dom_family == PF_INET) || (so->so_proto->pr_domain->dom_family == PF_INET6) || (so->so_proto->pr_domain->dom_family == PF_ROUTE))) so->so_fibnum = optval; else so->so_fibnum = 0; break; case SO_USER_COOKIE: error = sooptcopyin(sopt, &val32, sizeof val32, sizeof val32); if (error) goto bad; so->so_user_cookie = val32; break; case SO_SNDBUF: case SO_RCVBUF: case SO_SNDLOWAT: case SO_RCVLOWAT: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; /* * Values < 1 make no sense for any of these options, * so disallow them. */ if (optval < 1) { error = EINVAL; goto bad; } error = sbsetopt(so, sopt->sopt_name, optval); break; case SO_SNDTIMEO: case SO_RCVTIMEO: #ifdef COMPAT_FREEBSD32 if (SV_CURPROC_FLAG(SV_ILP32)) { struct timeval32 tv32; error = sooptcopyin(sopt, &tv32, sizeof tv32, sizeof tv32); CP(tv32, tv, tv_sec); CP(tv32, tv, tv_usec); } else #endif error = sooptcopyin(sopt, &tv, sizeof tv, sizeof tv); if (error) goto bad; if (tv.tv_sec < 0 || tv.tv_usec < 0 || tv.tv_usec >= 1000000) { error = EDOM; goto bad; } if (tv.tv_sec > INT32_MAX) val = SBT_MAX; else val = tvtosbt(tv); switch (sopt->sopt_name) { case SO_SNDTIMEO: so->so_snd.sb_timeo = val; break; case SO_RCVTIMEO: so->so_rcv.sb_timeo = val; break; } break; case SO_LABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof extmac, sizeof extmac); if (error) goto bad; error = mac_setsockopt_label(sopt->sopt_td->td_ucred, so, &extmac); #else error = EOPNOTSUPP; #endif break; case SO_TS_CLOCK: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) goto bad; if (optval < 0 || optval > SO_TS_CLOCK_MAX) { error = EINVAL; goto bad; } so->so_ts_clock = optval; break; case SO_MAX_PACING_RATE: error = sooptcopyin(sopt, &val32, sizeof(val32), sizeof(val32)); if (error) goto bad; so->so_max_pacing_rate = val32; break; default: if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) error = hhook_run_socket(so, sopt, HHOOK_SOCKET_OPT); else error = ENOPROTOOPT; break; } if (error == 0 && so->so_proto->pr_ctloutput != NULL) (void)(*so->so_proto->pr_ctloutput)(so, sopt); } bad: CURVNET_RESTORE(); return (error); } /* * Helper routine for getsockopt. */ int sooptcopyout(struct sockopt *sopt, const void *buf, size_t len) { int error; size_t valsize; error = 0; /* * Documented get behavior is that we always return a value, possibly * truncated to fit in the user's buffer. Traditional behavior is * that we always tell the user precisely how much we copied, rather * than something useful like the total amount we had available for * her. Note that this interface is not idempotent; the entire * answer must be generated ahead of time. */ valsize = min(len, sopt->sopt_valsize); sopt->sopt_valsize = valsize; if (sopt->sopt_val != NULL) { if (sopt->sopt_td != NULL) error = copyout(buf, sopt->sopt_val, valsize); else bcopy(buf, sopt->sopt_val, valsize); } return (error); } int sogetopt(struct socket *so, struct sockopt *sopt) { int error, optval; struct linger l; struct timeval tv; #ifdef MAC struct mac extmac; #endif CURVNET_SET(so->so_vnet); error = 0; if (sopt->sopt_level != SOL_SOCKET) { if (so->so_proto->pr_ctloutput != NULL) error = (*so->so_proto->pr_ctloutput)(so, sopt); else error = ENOPROTOOPT; CURVNET_RESTORE(); return (error); } else { switch (sopt->sopt_name) { case SO_ACCEPTFILTER: error = accept_filt_getopt(so, sopt); break; case SO_LINGER: SOCK_LOCK(so); l.l_onoff = so->so_options & SO_LINGER; l.l_linger = so->so_linger; SOCK_UNLOCK(so); error = sooptcopyout(sopt, &l, sizeof l); break; case SO_USELOOPBACK: case SO_DONTROUTE: case SO_DEBUG: case SO_KEEPALIVE: case SO_REUSEADDR: case SO_REUSEPORT: case SO_REUSEPORT_LB: case SO_BROADCAST: case SO_OOBINLINE: case SO_ACCEPTCONN: case SO_TIMESTAMP: case SO_BINTIME: case SO_NOSIGPIPE: case SO_NO_DDP: case SO_NO_OFFLOAD: optval = so->so_options & sopt->sopt_name; integer: error = sooptcopyout(sopt, &optval, sizeof optval); break; case SO_DOMAIN: optval = so->so_proto->pr_domain->dom_family; goto integer; case SO_TYPE: optval = so->so_type; goto integer; case SO_PROTOCOL: optval = so->so_proto->pr_protocol; goto integer; case SO_ERROR: SOCK_LOCK(so); optval = so->so_error; so->so_error = 0; SOCK_UNLOCK(so); goto integer; case SO_SNDBUF: optval = SOLISTENING(so) ? so->sol_sbsnd_hiwat : so->so_snd.sb_hiwat; goto integer; case SO_RCVBUF: optval = SOLISTENING(so) ? so->sol_sbrcv_hiwat : so->so_rcv.sb_hiwat; goto integer; case SO_SNDLOWAT: optval = SOLISTENING(so) ? so->sol_sbsnd_lowat : so->so_snd.sb_lowat; goto integer; case SO_RCVLOWAT: optval = SOLISTENING(so) ? so->sol_sbrcv_lowat : so->so_rcv.sb_lowat; goto integer; case SO_SNDTIMEO: case SO_RCVTIMEO: tv = sbttotv(sopt->sopt_name == SO_SNDTIMEO ? so->so_snd.sb_timeo : so->so_rcv.sb_timeo); #ifdef COMPAT_FREEBSD32 if (SV_CURPROC_FLAG(SV_ILP32)) { struct timeval32 tv32; CP(tv, tv32, tv_sec); CP(tv, tv32, tv_usec); error = sooptcopyout(sopt, &tv32, sizeof tv32); } else #endif error = sooptcopyout(sopt, &tv, sizeof tv); break; case SO_LABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof(extmac), sizeof(extmac)); if (error) goto bad; error = mac_getsockopt_label(sopt->sopt_td->td_ucred, so, &extmac); if (error) goto bad; error = sooptcopyout(sopt, &extmac, sizeof extmac); #else error = EOPNOTSUPP; #endif break; case SO_PEERLABEL: #ifdef MAC error = sooptcopyin(sopt, &extmac, sizeof(extmac), sizeof(extmac)); if (error) goto bad; error = mac_getsockopt_peerlabel( sopt->sopt_td->td_ucred, so, &extmac); if (error) goto bad; error = sooptcopyout(sopt, &extmac, sizeof extmac); #else error = EOPNOTSUPP; #endif break; case SO_LISTENQLIMIT: optval = SOLISTENING(so) ? so->sol_qlimit : 0; goto integer; case SO_LISTENQLEN: optval = SOLISTENING(so) ? so->sol_qlen : 0; goto integer; case SO_LISTENINCQLEN: optval = SOLISTENING(so) ? so->sol_incqlen : 0; goto integer; case SO_TS_CLOCK: optval = so->so_ts_clock; goto integer; case SO_MAX_PACING_RATE: optval = so->so_max_pacing_rate; goto integer; default: if (V_socket_hhh[HHOOK_SOCKET_OPT]->hhh_nhooks > 0) error = hhook_run_socket(so, sopt, HHOOK_SOCKET_OPT); else error = ENOPROTOOPT; break; } } #ifdef MAC bad: #endif CURVNET_RESTORE(); return (error); } int soopt_getm(struct sockopt *sopt, struct mbuf **mp) { struct mbuf *m, *m_prev; int sopt_size = sopt->sopt_valsize; MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); if (m == NULL) return ENOBUFS; if (sopt_size > MLEN) { MCLGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); return ENOBUFS; } m->m_len = min(MCLBYTES, sopt_size); } else { m->m_len = min(MLEN, sopt_size); } sopt_size -= m->m_len; *mp = m; m_prev = m; while (sopt_size) { MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA); if (m == NULL) { m_freem(*mp); return ENOBUFS; } if (sopt_size > MLEN) { MCLGET(m, sopt->sopt_td != NULL ? M_WAITOK : M_NOWAIT); if ((m->m_flags & M_EXT) == 0) { m_freem(m); m_freem(*mp); return ENOBUFS; } m->m_len = min(MCLBYTES, sopt_size); } else { m->m_len = min(MLEN, sopt_size); } sopt_size -= m->m_len; m_prev->m_next = m; m_prev = m; } return (0); } int soopt_mcopyin(struct sockopt *sopt, struct mbuf *m) { struct mbuf *m0 = m; if (sopt->sopt_val == NULL) return (0); while (m != NULL && sopt->sopt_valsize >= m->m_len) { if (sopt->sopt_td != NULL) { int error; error = copyin(sopt->sopt_val, mtod(m, char *), m->m_len); if (error != 0) { m_freem(m0); return(error); } } else bcopy(sopt->sopt_val, mtod(m, char *), m->m_len); sopt->sopt_valsize -= m->m_len; sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; m = m->m_next; } if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */ panic("ip6_sooptmcopyin"); return (0); } int soopt_mcopyout(struct sockopt *sopt, struct mbuf *m) { struct mbuf *m0 = m; size_t valsize = 0; if (sopt->sopt_val == NULL) return (0); while (m != NULL && sopt->sopt_valsize >= m->m_len) { if (sopt->sopt_td != NULL) { int error; error = copyout(mtod(m, char *), sopt->sopt_val, m->m_len); if (error != 0) { m_freem(m0); return(error); } } else bcopy(mtod(m, char *), sopt->sopt_val, m->m_len); sopt->sopt_valsize -= m->m_len; sopt->sopt_val = (char *)sopt->sopt_val + m->m_len; valsize += m->m_len; m = m->m_next; } if (m != NULL) { /* enough soopt buffer should be given from user-land */ m_freem(m0); return(EINVAL); } sopt->sopt_valsize = valsize; return (0); } /* * sohasoutofband(): protocol notifies socket layer of the arrival of new * out-of-band data, which will then notify socket consumers. */ void sohasoutofband(struct socket *so) { if (so->so_sigio != NULL) pgsigio(&so->so_sigio, SIGURG, 0); selwakeuppri(&so->so_rdsel, PSOCK); } int sopoll(struct socket *so, int events, struct ucred *active_cred, struct thread *td) { /* * We do not need to set or assert curvnet as long as everyone uses * sopoll_generic(). */ return (so->so_proto->pr_usrreqs->pru_sopoll(so, events, active_cred, td)); } int sopoll_generic(struct socket *so, int events, struct ucred *active_cred, struct thread *td) { int revents; SOCK_LOCK(so); if (SOLISTENING(so)) { if (!(events & (POLLIN | POLLRDNORM))) revents = 0; else if (!TAILQ_EMPTY(&so->sol_comp)) revents = events & (POLLIN | POLLRDNORM); else if ((events & POLLINIGNEOF) == 0 && so->so_error) revents = (events & (POLLIN | POLLRDNORM)) | POLLHUP; else { selrecord(td, &so->so_rdsel); revents = 0; } } else { revents = 0; SOCKBUF_LOCK(&so->so_snd); SOCKBUF_LOCK(&so->so_rcv); if (events & (POLLIN | POLLRDNORM)) if (soreadabledata(so)) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (sowriteable(so)) revents |= events & (POLLOUT | POLLWRNORM); if (events & (POLLPRI | POLLRDBAND)) if (so->so_oobmark || (so->so_rcv.sb_state & SBS_RCVATMARK)) revents |= events & (POLLPRI | POLLRDBAND); if ((events & POLLINIGNEOF) == 0) { if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { revents |= events & (POLLIN | POLLRDNORM); if (so->so_snd.sb_state & SBS_CANTSENDMORE) revents |= POLLHUP; } } if (so->so_rcv.sb_state & SBS_CANTRCVMORE) revents |= events & POLLRDHUP; if (revents == 0) { if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND | POLLRDHUP)) { selrecord(td, &so->so_rdsel); so->so_rcv.sb_flags |= SB_SEL; } if (events & (POLLOUT | POLLWRNORM)) { selrecord(td, &so->so_wrsel); so->so_snd.sb_flags |= SB_SEL; } } SOCKBUF_UNLOCK(&so->so_rcv); SOCKBUF_UNLOCK(&so->so_snd); } SOCK_UNLOCK(so); return (revents); } int soo_kqfilter(struct file *fp, struct knote *kn) { struct socket *so = kn->kn_fp->f_data; struct sockbuf *sb; struct knlist *knl; switch (kn->kn_filter) { case EVFILT_READ: kn->kn_fop = &soread_filtops; knl = &so->so_rdsel.si_note; sb = &so->so_rcv; break; case EVFILT_WRITE: kn->kn_fop = &sowrite_filtops; knl = &so->so_wrsel.si_note; sb = &so->so_snd; break; case EVFILT_EMPTY: kn->kn_fop = &soempty_filtops; knl = &so->so_wrsel.si_note; sb = &so->so_snd; break; default: return (EINVAL); } SOCK_LOCK(so); if (SOLISTENING(so)) { knlist_add(knl, kn, 1); } else { SOCKBUF_LOCK(sb); knlist_add(knl, kn, 1); sb->sb_flags |= SB_KNOTE; SOCKBUF_UNLOCK(sb); } SOCK_UNLOCK(so); return (0); } /* * Some routines that return EOPNOTSUPP for entry points that are not * supported by a protocol. Fill in as needed. */ int pru_accept_notsupp(struct socket *so, struct sockaddr **nam) { return EOPNOTSUPP; } int pru_aio_queue_notsupp(struct socket *so, struct kaiocb *job) { return EOPNOTSUPP; } int pru_attach_notsupp(struct socket *so, int proto, struct thread *td) { return EOPNOTSUPP; } int pru_bind_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) { return EOPNOTSUPP; } int pru_bindat_notsupp(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { return EOPNOTSUPP; } int pru_connect_notsupp(struct socket *so, struct sockaddr *nam, struct thread *td) { return EOPNOTSUPP; } int pru_connectat_notsupp(int fd, struct socket *so, struct sockaddr *nam, struct thread *td) { return EOPNOTSUPP; } int pru_connect2_notsupp(struct socket *so1, struct socket *so2) { return EOPNOTSUPP; } int pru_control_notsupp(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td) { return EOPNOTSUPP; } int pru_disconnect_notsupp(struct socket *so) { return EOPNOTSUPP; } int pru_listen_notsupp(struct socket *so, int backlog, struct thread *td) { return EOPNOTSUPP; } int pru_peeraddr_notsupp(struct socket *so, struct sockaddr **nam) { return EOPNOTSUPP; } int pru_rcvd_notsupp(struct socket *so, int flags) { return EOPNOTSUPP; } int pru_rcvoob_notsupp(struct socket *so, struct mbuf *m, int flags) { return EOPNOTSUPP; } int pru_send_notsupp(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, struct mbuf *control, struct thread *td) { if (control != NULL) m_freem(control); if ((flags & PRUS_NOTREADY) == 0) m_freem(m); return (EOPNOTSUPP); } int pru_ready_notsupp(struct socket *so, struct mbuf *m, int count) { return (EOPNOTSUPP); } /* * This isn't really a ``null'' operation, but it's the default one and * doesn't do anything destructive. */ int pru_sense_null(struct socket *so, struct stat *sb) { sb->st_blksize = so->so_snd.sb_hiwat; return 0; } int pru_shutdown_notsupp(struct socket *so) { return EOPNOTSUPP; } int pru_sockaddr_notsupp(struct socket *so, struct sockaddr **nam) { return EOPNOTSUPP; } int pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio, struct mbuf *top, struct mbuf *control, int flags, struct thread *td) { return EOPNOTSUPP; } int pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr, struct uio *uio, struct mbuf **mp0, struct mbuf **controlp, int *flagsp) { return EOPNOTSUPP; } int pru_sopoll_notsupp(struct socket *so, int events, struct ucred *cred, struct thread *td) { return EOPNOTSUPP; } static void filt_sordetach(struct knote *kn) { struct socket *so = kn->kn_fp->f_data; so_rdknl_lock(so); knlist_remove(&so->so_rdsel.si_note, kn, 1); if (!SOLISTENING(so) && knlist_empty(&so->so_rdsel.si_note)) so->so_rcv.sb_flags &= ~SB_KNOTE; so_rdknl_unlock(so); } /*ARGSUSED*/ static int filt_soread(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) { SOCK_LOCK_ASSERT(so); kn->kn_data = so->sol_qlen; if (so->so_error) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } return (!TAILQ_EMPTY(&so->sol_comp)); } SOCKBUF_LOCK_ASSERT(&so->so_rcv); kn->kn_data = sbavail(&so->so_rcv) - so->so_rcv.sb_ctl; if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } else if (so->so_error) /* temporary udp error */ return (1); if (kn->kn_sfflags & NOTE_LOWAT) { if (kn->kn_data >= kn->kn_sdata) return (1); } else if (sbavail(&so->so_rcv) >= so->so_rcv.sb_lowat) return (1); /* This hook returning non-zero indicates an event, not error */ return (hhook_run_socket(so, NULL, HHOOK_FILT_SOREAD)); } static void filt_sowdetach(struct knote *kn) { struct socket *so = kn->kn_fp->f_data; so_wrknl_lock(so); knlist_remove(&so->so_wrsel.si_note, kn, 1); if (!SOLISTENING(so) && knlist_empty(&so->so_wrsel.si_note)) so->so_snd.sb_flags &= ~SB_KNOTE; so_wrknl_unlock(so); } /*ARGSUSED*/ static int filt_sowrite(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) return (0); SOCKBUF_LOCK_ASSERT(&so->so_snd); kn->kn_data = sbspace(&so->so_snd); hhook_run_socket(so, kn, HHOOK_FILT_SOWRITE); if (so->so_snd.sb_state & SBS_CANTSENDMORE) { kn->kn_flags |= EV_EOF; kn->kn_fflags = so->so_error; return (1); } else if (so->so_error) /* temporary udp error */ return (1); else if (((so->so_state & SS_ISCONNECTED) == 0) && (so->so_proto->pr_flags & PR_CONNREQUIRED)) return (0); else if (kn->kn_sfflags & NOTE_LOWAT) return (kn->kn_data >= kn->kn_sdata); else return (kn->kn_data >= so->so_snd.sb_lowat); } static int filt_soempty(struct knote *kn, long hint) { struct socket *so; so = kn->kn_fp->f_data; if (SOLISTENING(so)) return (1); SOCKBUF_LOCK_ASSERT(&so->so_snd); kn->kn_data = sbused(&so->so_snd); if (kn->kn_data == 0) return (1); else return (0); } int socheckuid(struct socket *so, uid_t uid) { if (so == NULL) return (EPERM); if (so->so_cred->cr_uid != uid) return (EPERM); return (0); } /* * These functions are used by protocols to notify the socket layer (and its * consumers) of state changes in the sockets driven by protocol-side events. */ /* * Procedures to manipulate state flags of socket and do appropriate wakeups. * * Normal sequence from the active (originating) side is that * soisconnecting() is called during processing of connect() call, resulting * in an eventual call to soisconnected() if/when the connection is * established. When the connection is torn down soisdisconnecting() is * called during processing of disconnect() call, and soisdisconnected() is * called when the connection to the peer is totally severed. The semantics * of these routines are such that connectionless protocols can call * soisconnected() and soisdisconnected() only, bypassing the in-progress * calls when setting up a ``connection'' takes no time. * * From the passive side, a socket is created with two queues of sockets: * so_incomp for connections in progress and so_comp for connections already * made and awaiting user acceptance. As a protocol is preparing incoming * connections, it creates a socket structure queued on so_incomp by calling * sonewconn(). When the connection is established, soisconnected() is * called, and transfers the socket structure to so_comp, making it available * to accept(). * * If a socket is closed with sockets on either so_incomp or so_comp, these * sockets are dropped. * * If higher-level protocols are implemented in the kernel, the wakeups done * here will sometimes cause software-interrupt process scheduling. */ void soisconnecting(struct socket *so) { SOCK_LOCK(so); so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); so->so_state |= SS_ISCONNECTING; SOCK_UNLOCK(so); } void soisconnected(struct socket *so) { SOCK_LOCK(so); so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING); so->so_state |= SS_ISCONNECTED; if (so->so_qstate == SQ_INCOMP) { struct socket *head = so->so_listen; int ret; KASSERT(head, ("%s: so %p on incomp of NULL", __func__, so)); /* * Promoting a socket from incomplete queue to complete, we * need to go through reverse order of locking. We first do * trylock, and if that doesn't succeed, we go the hard way * leaving a reference and rechecking consistency after proper * locking. */ if (__predict_false(SOLISTEN_TRYLOCK(head) == 0)) { soref(head); SOCK_UNLOCK(so); SOLISTEN_LOCK(head); SOCK_LOCK(so); if (__predict_false(head != so->so_listen)) { /* * The socket went off the listen queue, * should be lost race to close(2) of sol. * The socket is about to soabort(). */ SOCK_UNLOCK(so); sorele(head); return; } /* Not the last one, as so holds a ref. */ refcount_release(&head->so_count); } again: if ((so->so_options & SO_ACCEPTFILTER) == 0) { TAILQ_REMOVE(&head->sol_incomp, so, so_list); head->sol_incqlen--; TAILQ_INSERT_TAIL(&head->sol_comp, so, so_list); head->sol_qlen++; so->so_qstate = SQ_COMP; SOCK_UNLOCK(so); solisten_wakeup(head); /* unlocks */ } else { SOCKBUF_LOCK(&so->so_rcv); soupcall_set(so, SO_RCV, head->sol_accept_filter->accf_callback, head->sol_accept_filter_arg); so->so_options &= ~SO_ACCEPTFILTER; ret = head->sol_accept_filter->accf_callback(so, head->sol_accept_filter_arg, M_NOWAIT); if (ret == SU_ISCONNECTED) { soupcall_clear(so, SO_RCV); SOCKBUF_UNLOCK(&so->so_rcv); goto again; } SOCKBUF_UNLOCK(&so->so_rcv); SOCK_UNLOCK(so); SOLISTEN_UNLOCK(head); } return; } SOCK_UNLOCK(so); wakeup(&so->so_timeo); sorwakeup(so); sowwakeup(so); } void soisdisconnecting(struct socket *so) { SOCK_LOCK(so); so->so_state &= ~SS_ISCONNECTING; so->so_state |= SS_ISDISCONNECTING; if (!SOLISTENING(so)) { SOCKBUF_LOCK(&so->so_rcv); socantrcvmore_locked(so); SOCKBUF_LOCK(&so->so_snd); socantsendmore_locked(so); } SOCK_UNLOCK(so); wakeup(&so->so_timeo); } void soisdisconnected(struct socket *so) { SOCK_LOCK(so); /* * There is at least one reader of so_state that does not * acquire socket lock, namely soreceive_generic(). Ensure * that it never sees all flags that track connection status * cleared, by ordering the update with a barrier semantic of * our release thread fence. */ so->so_state |= SS_ISDISCONNECTED; atomic_thread_fence_rel(); so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); if (!SOLISTENING(so)) { SOCK_UNLOCK(so); SOCKBUF_LOCK(&so->so_rcv); socantrcvmore_locked(so); SOCKBUF_LOCK(&so->so_snd); sbdrop_locked(&so->so_snd, sbused(&so->so_snd)); socantsendmore_locked(so); } else SOCK_UNLOCK(so); wakeup(&so->so_timeo); } /* * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. */ struct sockaddr * sodupsockaddr(const struct sockaddr *sa, int mflags) { struct sockaddr *sa2; sa2 = malloc(sa->sa_len, M_SONAME, mflags); if (sa2) bcopy(sa, sa2, sa->sa_len); return sa2; } /* * Register per-socket destructor. */ void sodtor_set(struct socket *so, so_dtor_t *func) { SOCK_LOCK_ASSERT(so); so->so_dtor = func; } /* * Register per-socket buffer upcalls. */ void soupcall_set(struct socket *so, int which, so_upcall_t func, void *arg) { struct sockbuf *sb; KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); switch (which) { case SO_RCV: sb = &so->so_rcv; break; case SO_SND: sb = &so->so_snd; break; default: panic("soupcall_set: bad which"); } SOCKBUF_LOCK_ASSERT(sb); sb->sb_upcall = func; sb->sb_upcallarg = arg; sb->sb_flags |= SB_UPCALL; } void soupcall_clear(struct socket *so, int which) { struct sockbuf *sb; KASSERT(!SOLISTENING(so), ("%s: so %p listening", __func__, so)); switch (which) { case SO_RCV: sb = &so->so_rcv; break; case SO_SND: sb = &so->so_snd; break; default: panic("soupcall_clear: bad which"); } SOCKBUF_LOCK_ASSERT(sb); KASSERT(sb->sb_upcall != NULL, ("%s: so %p no upcall to clear", __func__, so)); sb->sb_upcall = NULL; sb->sb_upcallarg = NULL; sb->sb_flags &= ~SB_UPCALL; } void solisten_upcall_set(struct socket *so, so_upcall_t func, void *arg) { SOLISTEN_LOCK_ASSERT(so); so->sol_upcall = func; so->sol_upcallarg = arg; } static void so_rdknl_lock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOCK_LOCK(so); else SOCKBUF_LOCK(&so->so_rcv); } static void so_rdknl_unlock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOCK_UNLOCK(so); else SOCKBUF_UNLOCK(&so->so_rcv); } static void so_rdknl_assert_lock(void *arg, int what) { struct socket *so = arg; if (what == LA_LOCKED) { if (SOLISTENING(so)) SOCK_LOCK_ASSERT(so); else SOCKBUF_LOCK_ASSERT(&so->so_rcv); } else { if (SOLISTENING(so)) SOCK_UNLOCK_ASSERT(so); else SOCKBUF_UNLOCK_ASSERT(&so->so_rcv); } } static void so_wrknl_lock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOCK_LOCK(so); else SOCKBUF_LOCK(&so->so_snd); } static void so_wrknl_unlock(void *arg) { struct socket *so = arg; if (SOLISTENING(so)) SOCK_UNLOCK(so); else SOCKBUF_UNLOCK(&so->so_snd); } static void so_wrknl_assert_lock(void *arg, int what) { struct socket *so = arg; if (what == LA_LOCKED) { if (SOLISTENING(so)) SOCK_LOCK_ASSERT(so); else SOCKBUF_LOCK_ASSERT(&so->so_snd); } else { if (SOLISTENING(so)) SOCK_UNLOCK_ASSERT(so); else SOCKBUF_UNLOCK_ASSERT(&so->so_snd); } } /* * Create an external-format (``xsocket'') structure using the information in * the kernel-format socket structure pointed to by so. This is done to * reduce the spew of irrelevant information over this interface, to isolate * user code from changes in the kernel structure, and potentially to provide * information-hiding if we decide that some of this information should be * hidden from users. */ void sotoxsocket(struct socket *so, struct xsocket *xso) { bzero(xso, sizeof(*xso)); xso->xso_len = sizeof *xso; xso->xso_so = (uintptr_t)so; xso->so_type = so->so_type; xso->so_options = so->so_options; xso->so_linger = so->so_linger; xso->so_state = so->so_state; xso->so_pcb = (uintptr_t)so->so_pcb; xso->xso_protocol = so->so_proto->pr_protocol; xso->xso_family = so->so_proto->pr_domain->dom_family; xso->so_timeo = so->so_timeo; xso->so_error = so->so_error; xso->so_uid = so->so_cred->cr_uid; xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; if (SOLISTENING(so)) { xso->so_qlen = so->sol_qlen; xso->so_incqlen = so->sol_incqlen; xso->so_qlimit = so->sol_qlimit; xso->so_oobmark = 0; } else { xso->so_state |= so->so_qstate; xso->so_qlen = xso->so_incqlen = xso->so_qlimit = 0; xso->so_oobmark = so->so_oobmark; sbtoxsockbuf(&so->so_snd, &xso->so_snd); sbtoxsockbuf(&so->so_rcv, &xso->so_rcv); } } struct sockbuf * so_sockbuf_rcv(struct socket *so) { return (&so->so_rcv); } struct sockbuf * so_sockbuf_snd(struct socket *so) { return (&so->so_snd); } int so_state_get(const struct socket *so) { return (so->so_state); } void so_state_set(struct socket *so, int val) { so->so_state = val; } int so_options_get(const struct socket *so) { return (so->so_options); } void so_options_set(struct socket *so, int val) { so->so_options = val; } int so_error_get(const struct socket *so) { return (so->so_error); } void so_error_set(struct socket *so, int val) { so->so_error = val; } int so_linger_get(const struct socket *so) { return (so->so_linger); } void so_linger_set(struct socket *so, int val) { KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz), ("%s: val %d out of range", __func__, val)); so->so_linger = val; } struct protosw * so_protosw_get(const struct socket *so) { return (so->so_proto); } void so_protosw_set(struct socket *so, struct protosw *val) { so->so_proto = val; } void so_sorwakeup(struct socket *so) { sorwakeup(so); } void so_sowwakeup(struct socket *so) { sowwakeup(so); } void so_sorwakeup_locked(struct socket *so) { sorwakeup_locked(so); } void so_sowwakeup_locked(struct socket *so) { sowwakeup_locked(so); } void so_lock(struct socket *so) { SOCK_LOCK(so); } void so_unlock(struct socket *so) { SOCK_UNLOCK(so); }