/* $NetBSD: kern_sysctl.c,v 1.266.20.1 2024/09/20 09:36:13 martin Exp $ */ /*- * Copyright (c) 2003, 2007, 2008 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Andrew Brown. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /*- * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Mike Karels at Berkeley Software Design, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. 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. * * @(#)kern_sysctl.c 8.9 (Berkeley) 5/20/95 */ /* * sysctl system call. */ #define __COMPAT_SYSCTL #include __KERNEL_RCSID(0, "$NetBSD: kern_sysctl.c,v 1.266.20.1 2024/09/20 09:36:13 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_defcorename.h" #endif #include "ksyms.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAXDESCLEN 1024 MALLOC_DEFINE(M_SYSCTLNODE, "sysctlnode", "sysctl node structures"); MALLOC_DEFINE(M_SYSCTLDATA, "sysctldata", "misc sysctl data"); static int sysctl_mmap(SYSCTLFN_PROTO); static int sysctl_alloc(struct sysctlnode *, int); static int sysctl_realloc(struct sysctlnode *); static int sysctl_cvt_in(struct lwp *, int *, const void *, size_t, struct sysctlnode *); static int sysctl_cvt_out(struct lwp *, int, const struct sysctlnode *, void *, size_t, size_t *); static int sysctl_log_add(struct sysctllog **, const struct sysctlnode *); static int sysctl_log_realloc(struct sysctllog *); typedef void sysctl_setup_func(struct sysctllog **); #ifdef SYSCTL_DEBUG #define DPRINTF(a) printf a #else #define DPRINTF(a) #endif struct sysctllog { const struct sysctlnode *log_root; int *log_num; int log_size, log_left; }; /* * the "root" of the new sysctl tree */ struct sysctlnode sysctl_root = { .sysctl_flags = SYSCTL_VERSION| CTLFLAG_ROOT|CTLFLAG_READWRITE| CTLTYPE_NODE, .sysctl_num = 0, .sysctl_size = sizeof(struct sysctlnode), .sysctl_name = "(root)", }; /* * link set of functions that add nodes at boot time (see also * sysctl_buildtree()) */ __link_set_decl(sysctl_funcs, sysctl_setup_func); /* * The `sysctl_treelock' is intended to serialize access to the sysctl * tree. XXX This has serious problems; allocating memory and * copying data out with the lock held is insane. */ krwlock_t sysctl_treelock; kmutex_t sysctl_file_marker_lock; /* * Attributes stored in the kernel. */ char hostname[MAXHOSTNAMELEN]; int hostnamelen; char domainname[MAXHOSTNAMELEN]; int domainnamelen; long hostid; #ifndef DEFCORENAME #define DEFCORENAME "%n.core" #endif char defcorename[MAXPATHLEN] = DEFCORENAME; /* * ******************************************************************** * Section 0: Some simple glue * ******************************************************************** * By wrapping copyin(), copyout(), and copyinstr() like this, we can * stop caring about who's calling us and simplify some code a bunch. * ******************************************************************** */ int sysctl_copyin(struct lwp *l, const void *uaddr, void *kaddr, size_t len) { int error; if (l != NULL) { error = copyin(uaddr, kaddr, len); ktrmibio(-1, UIO_WRITE, uaddr, len, error); } else { error = kcopy(uaddr, kaddr, len); } return error; } int sysctl_copyout(struct lwp *l, const void *kaddr, void *uaddr, size_t len) { int error; if (l != NULL) { error = copyout(kaddr, uaddr, len); ktrmibio(-1, UIO_READ, uaddr, len, error); } else { error = kcopy(kaddr, uaddr, len); } return error; } int sysctl_copyinstr(struct lwp *l, const void *uaddr, void *kaddr, size_t len, size_t *done) { int error; if (l != NULL) { error = copyinstr(uaddr, kaddr, len, done); ktrmibio(-1, UIO_WRITE, uaddr, len, error); } else { error = copystr(uaddr, kaddr, len, done); } return error; } /* * ******************************************************************** * Initialize sysctl subsystem. * ******************************************************************** */ void sysctl_init(void) { sysctl_setup_func *const *sysctl_setup; rw_init(&sysctl_treelock); /* * dynamic mib numbers start here */ sysctl_root.sysctl_num = CREATE_BASE; sysctl_basenode_init(); __link_set_foreach(sysctl_setup, sysctl_funcs) { (**sysctl_setup)(NULL); } mutex_init(&sysctl_file_marker_lock, MUTEX_DEFAULT, IPL_NONE); } /* * Setting this means no more permanent nodes can be added, * trees that claim to be readonly at the root now are, and if * the main tree is readonly, *everything* is. * * Also starts up the PRNG used for the "random" sysctl: it's * better to start it later than sooner. * * Call this at the end of kernel init. */ void sysctl_finalize(void) { sysctl_root.sysctl_flags |= CTLFLAG_PERMANENT; } /* * ******************************************************************** * The main native sysctl system call itself. * ******************************************************************** */ int sys___sysctl(struct lwp *l, const struct sys___sysctl_args *uap, register_t *retval) { /* { syscallarg(const int *) name; syscallarg(u_int) namelen; syscallarg(void *) old; syscallarg(size_t *) oldlenp; syscallarg(const void *) new; syscallarg(size_t) newlen; } */ int error, nerror, name[CTL_MAXNAME]; size_t oldlen, savelen, *oldlenp; /* * get oldlen */ oldlen = 0; oldlenp = SCARG(uap, oldlenp); if (oldlenp != NULL) { error = copyin(oldlenp, &oldlen, sizeof(oldlen)); if (error) return (error); } savelen = oldlen; /* * top-level sysctl names may or may not be non-terminal, but * we don't care */ if (SCARG(uap, namelen) > CTL_MAXNAME || SCARG(uap, namelen) < 1) return (EINVAL); error = copyin(SCARG(uap, name), &name, SCARG(uap, namelen) * sizeof(int)); if (error) return (error); ktrmib(name, SCARG(uap, namelen)); sysctl_lock(SCARG(uap, newv) != NULL); /* * do sysctl work (NULL means main built-in default tree) */ error = sysctl_dispatch(&name[0], SCARG(uap, namelen), SCARG(uap, oldv), &oldlen, SCARG(uap, newv), SCARG(uap, newlen), &name[0], l, NULL); /* * release the sysctl lock */ sysctl_unlock(); /* * set caller's oldlen to new value even in the face of an * error (if this gets an error and they didn't have one, they * get this one) */ if (oldlenp) { nerror = copyout(&oldlen, oldlenp, sizeof(oldlen)); if (error == 0) error = nerror; } /* * if the only problem is that we weren't given enough space, * that's an ENOMEM error */ if (error == 0 && SCARG(uap, oldv) != NULL && savelen < oldlen) error = ENOMEM; return (error); } /* * ******************************************************************** * Section 1: How the tree is used * ******************************************************************** * Implementations of sysctl for emulations should typically need only * these three functions in this order: lock the tree, dispatch * request into it, unlock the tree. * ******************************************************************** */ void sysctl_lock(bool write) { if (write) { rw_enter(&sysctl_treelock, RW_WRITER); curlwp->l_pflag |= LP_SYSCTLWRITE; } else { rw_enter(&sysctl_treelock, RW_READER); curlwp->l_pflag &= ~LP_SYSCTLWRITE; } } void sysctl_relock(void) { if ((curlwp->l_pflag & LP_SYSCTLWRITE) != 0) { rw_enter(&sysctl_treelock, RW_WRITER); } else { rw_enter(&sysctl_treelock, RW_READER); } } /* * ******************************************************************** * the main sysctl dispatch routine. scans the given tree and picks a * function to call based on what it finds. * ******************************************************************** */ int sysctl_dispatch(SYSCTLFN_ARGS) { int error; sysctlfn fn; int ni; KASSERT(rw_lock_held(&sysctl_treelock)); if (rnode && SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_dispatch: rnode %p wrong version\n", rnode); error = EINVAL; goto out; } fn = NULL; error = sysctl_locate(l, name, namelen, &rnode, &ni); if (rnode->sysctl_func != NULL) { /* * the node we ended up at has a function, so call it. it can * hand off to query or create if it wants to. */ fn = rnode->sysctl_func; } else if (error == 0) { /* * we found the node they were looking for, so do a lookup. */ fn = (sysctlfn)sysctl_lookup; /* XXX may write to rnode */ } else if (error == ENOENT && (ni + 1) == namelen && name[ni] < 0) { /* * prospective parent node found, but the terminal node was * not. generic operations associate with the parent. */ switch (name[ni]) { case CTL_QUERY: fn = sysctl_query; break; case CTL_CREATE: #if NKSYMS > 0 case CTL_CREATESYM: #endif /* NKSYMS > 0 */ if (newp == NULL) { error = EINVAL; break; } KASSERT(rw_write_held(&sysctl_treelock)); fn = (sysctlfn)sysctl_create; /* we own the rnode */ break; case CTL_DESTROY: if (newp == NULL) { error = EINVAL; break; } KASSERT(rw_write_held(&sysctl_treelock)); fn = (sysctlfn)sysctl_destroy; /* we own the rnode */ break; case CTL_MMAP: fn = (sysctlfn)sysctl_mmap; /* we own the rnode */ break; case CTL_DESCRIBE: fn = sysctl_describe; break; default: error = EOPNOTSUPP; break; } } /* * after all of that, maybe we found someone who knows how to * get us what we want? */ if (fn != NULL) error = (*fn)(name + ni, namelen - ni, oldp, oldlenp, newp, newlen, name, l, rnode); else if (error == 0) error = EOPNOTSUPP; out: return (error); } /* * ******************************************************************** * Releases the tree lock. * ******************************************************************** */ void sysctl_unlock(void) { rw_exit(&sysctl_treelock); } /* * ******************************************************************** * Section 2: The main tree interfaces * ******************************************************************** * This is how sysctl_dispatch() does its work, and you can too, by * calling these routines from helpers (though typically only * sysctl_lookup() will be used). The tree MUST BE LOCKED when these * are called. * ******************************************************************** */ /* * sysctl_locate -- Finds the node matching the given mib under the * given tree (via rv). If no tree is given, we fall back to the * native tree. The current process (via l) is used for access * control on the tree (some nodes may be traversable only by root) and * on return, nip will show how many numbers in the mib were consumed. */ int sysctl_locate(struct lwp *l, const int *name, u_int namelen, const struct sysctlnode **rnode, int *nip) { const struct sysctlnode *node, *pnode; int tn, si, ni, error, alias; KASSERT(rw_lock_held(&sysctl_treelock)); /* * basic checks and setup */ if (*rnode == NULL) *rnode = &sysctl_root; if (nip) *nip = 0; if (namelen == 0) return (0); /* * search starts from "root" */ pnode = *rnode; if (SYSCTL_VERS(pnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_locate: pnode %p wrong version\n", pnode); return (EINVAL); } node = pnode->sysctl_child; error = 0; /* * scan for node to which new node should be attached */ for (ni = 0; ni < namelen; ni++) { /* * walked off bottom of tree */ if (node == NULL) { if (SYSCTL_TYPE(pnode->sysctl_flags) == CTLTYPE_NODE) error = ENOENT; else error = ENOTDIR; break; } /* * can anyone traverse this node or only root? */ if (l != NULL && (pnode->sysctl_flags & CTLFLAG_PRIVATE) && (error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_PRVT, NULL, NULL, NULL)) != 0) return (error); /* * find a child node with the right number */ tn = name[ni]; alias = 0; si = 0; /* * Note: ANYNUMBER only matches positive integers. * Since ANYNUMBER is only permitted on single-node * sub-trees (eg proc), check before the loop and skip * it if we can. */ if ((node[si].sysctl_flags & CTLFLAG_ANYNUMBER) && (tn >= 0)) goto foundit; for (; si < pnode->sysctl_clen; si++) { if (node[si].sysctl_num == tn) { if (node[si].sysctl_flags & CTLFLAG_ALIAS) { if (alias++ == 4) break; else { tn = node[si].sysctl_alias; si = -1; } } else goto foundit; } } /* * if we ran off the end, it obviously doesn't exist */ error = ENOENT; break; /* * so far so good, move on down the line */ foundit: pnode = &node[si]; if (SYSCTL_TYPE(pnode->sysctl_flags) == CTLTYPE_NODE) node = node[si].sysctl_child; else node = NULL; } *rnode = pnode; if (nip) *nip = ni; return (error); } /* * sysctl_query -- The auto-discovery engine. Copies out the structs * describing nodes under the given node and handles overlay trees. */ int sysctl_query(SYSCTLFN_ARGS) { int error, ni, elim, v; size_t out, left, t; const struct sysctlnode *enode, *onode; struct sysctlnode qnode; KASSERT(rw_lock_held(&sysctl_treelock)); if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_query: rnode %p wrong version\n", rnode); return (EINVAL); } if (SYSCTL_TYPE(rnode->sysctl_flags) != CTLTYPE_NODE) return (ENOTDIR); if (namelen != 1 || name[0] != CTL_QUERY) return (EINVAL); error = 0; out = 0; left = *oldlenp; elim = 0; enode = NULL; /* * translate the given request to a current node */ error = sysctl_cvt_in(l, &v, newp, newlen, &qnode); if (error) return (error); /* * if the request specifies a version, check it */ if (qnode.sysctl_ver != 0) { enode = rnode; if (qnode.sysctl_ver != enode->sysctl_ver && qnode.sysctl_ver != sysctl_rootof(enode)->sysctl_ver) return (EINVAL); } /* * process has overlay tree */ if (l && l->l_proc->p_emul->e_sysctlovly) { enode = l->l_proc->p_emul->e_sysctlovly; elim = (name - oname); error = sysctl_locate(l, oname, elim, &enode, NULL); if (error == 0) { /* ah, found parent in overlay */ elim = enode->sysctl_clen; enode = enode->sysctl_child; } else { error = 0; elim = 0; enode = NULL; } } for (ni = 0; ni < rnode->sysctl_clen; ni++) { onode = &rnode->sysctl_child[ni]; if (enode && enode->sysctl_num == onode->sysctl_num) { if (SYSCTL_TYPE(enode->sysctl_flags) != CTLTYPE_NODE) onode = enode; if (--elim > 0) enode++; else enode = NULL; } error = sysctl_cvt_out(l, v, onode, oldp, left, &t); if (error) return (error); if (oldp != NULL) oldp = (char*)oldp + t; out += t; left -= MIN(left, t); } /* * overlay trees *MUST* be entirely consumed */ KASSERT(enode == NULL); *oldlenp = out; return (error); } /* * sysctl_create -- Adds a node (the description of which is taken * from newp) to the tree, returning a copy of it in the space pointed * to by oldp. In the event that the requested slot is already taken * (either by name or by number), the offending node is returned * instead. Yes, this is complex, but we want to make sure everything * is proper. */ #ifdef SYSCTL_DEBUG_CREATE int _sysctl_create(SYSCTLFN_ARGS); int _sysctl_create(SYSCTLFN_ARGS) #else int sysctl_create(SYSCTLFN_ARGS) #endif { struct sysctlnode nnode, *node, *pnode; int error, ni, at, nm, type, nsz, sz, flags, anum, v; void *own; KASSERT(rw_write_held(&sysctl_treelock)); error = 0; own = NULL; anum = -1; if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_create: rnode %p wrong version\n", rnode); return (EINVAL); } if (namelen != 1 || (name[namelen - 1] != CTL_CREATE #if NKSYMS > 0 && name[namelen - 1] != CTL_CREATESYM #endif /* NKSYMS > 0 */ )) return (EINVAL); /* * processes can only add nodes at securelevel 0, must be * root, and can't add nodes to a parent that's not writeable */ if (l != NULL) { #ifndef SYSCTL_DISALLOW_CREATE error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_ADD, NULL, NULL, NULL); if (error) return (error); if (!(rnode->sysctl_flags & CTLFLAG_READWRITE)) #endif /* SYSCTL_DISALLOW_CREATE */ return (EPERM); } /* * nothing can add a node if: * we've finished initial set up of this tree and * (the tree itself is not writeable or * the entire sysctl system is not writeable) */ if ((sysctl_rootof(rnode)->sysctl_flags & CTLFLAG_PERMANENT) && (!(sysctl_rootof(rnode)->sysctl_flags & CTLFLAG_READWRITE) || !(sysctl_root.sysctl_flags & CTLFLAG_READWRITE))) return (EPERM); /* * it must be a "node", not a "int" or something */ if (SYSCTL_TYPE(rnode->sysctl_flags) != CTLTYPE_NODE) return (ENOTDIR); if (rnode->sysctl_flags & CTLFLAG_ALIAS) { printf("sysctl_create: attempt to add node to aliased " "node %p\n", rnode); return (EINVAL); } pnode = __UNCONST(rnode); /* we are adding children to this node */ if (newp == NULL) return (EINVAL); error = sysctl_cvt_in(l, &v, newp, newlen, &nnode); if (error) return (error); /* * nodes passed in don't *have* parents */ if (nnode.sysctl_parent != NULL) return (EINVAL); /* * if we are indeed adding it, it should be a "good" name and * number */ nm = nnode.sysctl_num; #if NKSYMS > 0 if (nm == CTL_CREATESYM) nm = CTL_CREATE; #endif /* NKSYMS > 0 */ if (nm < 0 && nm != CTL_CREATE) return (EINVAL); /* * the name can't start with a digit */ if (nnode.sysctl_name[0] >= '0' && nnode.sysctl_name[0] <= '9') return (EINVAL); /* * the name must be only alphanumerics or - or _, longer than * 0 bytes and less than SYSCTL_NAMELEN */ nsz = 0; while (nsz < SYSCTL_NAMELEN && nnode.sysctl_name[nsz] != '\0') { if ((nnode.sysctl_name[nsz] >= '0' && nnode.sysctl_name[nsz] <= '9') || (nnode.sysctl_name[nsz] >= 'A' && nnode.sysctl_name[nsz] <= 'Z') || (nnode.sysctl_name[nsz] >= 'a' && nnode.sysctl_name[nsz] <= 'z') || nnode.sysctl_name[nsz] == '-' || nnode.sysctl_name[nsz] == '_') nsz++; else return (EINVAL); } if (nsz == 0 || nsz == SYSCTL_NAMELEN) return (EINVAL); /* * various checks revolve around size vs type, etc */ type = SYSCTL_TYPE(nnode.sysctl_flags); flags = SYSCTL_FLAGS(nnode.sysctl_flags); sz = nnode.sysctl_size; /* * find out if there's a collision, and if so, let the caller * know what they collided with */ node = pnode->sysctl_child; at = 0; if (node) { if ((flags | node->sysctl_flags) & CTLFLAG_ANYNUMBER) /* No siblings for a CTLFLAG_ANYNUMBER node */ return EINVAL; for (ni = 0; ni < pnode->sysctl_clen; ni++) { if (nm == node[ni].sysctl_num || strcmp(nnode.sysctl_name, node[ni].sysctl_name) == 0) { /* * ignore error here, since we * are already fixed on EEXIST */ (void)sysctl_cvt_out(l, v, &node[ni], oldp, *oldlenp, oldlenp); return (EEXIST); } if (nm > node[ni].sysctl_num) at++; } } /* * use sysctl_ver to add to the tree iff it hasn't changed */ if (nnode.sysctl_ver != 0) { /* * a specified value must match either the parent * node's version or the root node's version */ if (nnode.sysctl_ver != sysctl_rootof(rnode)->sysctl_ver && nnode.sysctl_ver != rnode->sysctl_ver) { return (EINVAL); } } /* * only the kernel can assign functions to entries */ if (l != NULL && nnode.sysctl_func != NULL) return (EPERM); /* * only the kernel can create permanent entries, and only then * before the kernel is finished setting itself up */ if (l != NULL && (flags & ~SYSCTL_USERFLAGS)) return (EPERM); if ((flags & CTLFLAG_PERMANENT) & (sysctl_root.sysctl_flags & CTLFLAG_PERMANENT)) return (EPERM); if ((flags & (CTLFLAG_OWNDATA | CTLFLAG_IMMEDIATE)) == (CTLFLAG_OWNDATA | CTLFLAG_IMMEDIATE)) return (EINVAL); if ((flags & CTLFLAG_IMMEDIATE) && type != CTLTYPE_INT && type != CTLTYPE_QUAD && type != CTLTYPE_BOOL) return (EINVAL); /* * check size, or set it if unset and we can figure it out. * kernel created nodes are allowed to have a function instead * of a size (or a data pointer). */ switch (type) { case CTLTYPE_NODE: /* * only *i* can assert the size of a node */ if (flags & CTLFLAG_ALIAS) { anum = nnode.sysctl_alias; if (anum < 0) return (EINVAL); nnode.sysctl_alias = 0; } if (sz != 0 || nnode.sysctl_data != NULL) return (EINVAL); if (nnode.sysctl_csize != 0 || nnode.sysctl_clen != 0 || nnode.sysctl_child != 0) return (EINVAL); if (flags & CTLFLAG_OWNDATA) return (EINVAL); sz = sizeof(struct sysctlnode); break; case CTLTYPE_INT: /* * since an int is an int, if the size is not given or * is wrong, we can "int-uit" it. */ if (sz != 0 && sz != sizeof(int)) return (EINVAL); sz = sizeof(int); break; case CTLTYPE_STRING: /* * strings are a little more tricky */ if (sz == 0) { if (l == NULL) { if (nnode.sysctl_func == NULL) { if (nnode.sysctl_data == NULL) return (EINVAL); else sz = strlen(nnode.sysctl_data) + 1; } } else if (nnode.sysctl_data == NULL && flags & CTLFLAG_OWNDATA) { return (EINVAL); } else { char *vp, *e; size_t s; /* * we want a rough idea of what the * size is now */ vp = malloc(PAGE_SIZE, M_SYSCTLDATA, M_WAITOK); if (vp == NULL) return (ENOMEM); e = nnode.sysctl_data; do { error = copyinstr(e, vp, PAGE_SIZE, &s); if (error) { if (error != ENAMETOOLONG) { free(vp, M_SYSCTLDATA); return (error); } e += PAGE_SIZE; if ((e - 32 * PAGE_SIZE) > (char*)nnode.sysctl_data) { free(vp, M_SYSCTLDATA); return (ERANGE); } } } while (error != 0); sz = s + (e - (char*)nnode.sysctl_data); free(vp, M_SYSCTLDATA); } } break; case CTLTYPE_QUAD: if (sz != 0 && sz != sizeof(u_quad_t)) return (EINVAL); sz = sizeof(u_quad_t); break; case CTLTYPE_BOOL: /* * since an bool is an bool, if the size is not given or * is wrong, we can "intuit" it. */ if (sz != 0 && sz != sizeof(bool)) return (EINVAL); sz = sizeof(bool); break; case CTLTYPE_STRUCT: if (sz == 0) { if (l != NULL || nnode.sysctl_func == NULL) return (EINVAL); if (flags & CTLFLAG_OWNDATA) return (EINVAL); } break; default: return (EINVAL); } /* * at this point, if sz is zero, we *must* have a * function to go with it and we can't own it. */ /* * l ptr own * 0 0 0 -> EINVAL (if no func) * 0 0 1 -> own * 0 1 0 -> kptr * 0 1 1 -> kptr * 1 0 0 -> EINVAL * 1 0 1 -> own * 1 1 0 -> kptr, no own (fault on lookup) * 1 1 1 -> uptr, own */ if (type != CTLTYPE_NODE) { if (sz != 0) { if (flags & CTLFLAG_OWNDATA) { own = malloc(sz, M_SYSCTLDATA, M_WAITOK); if (own == NULL) return ENOMEM; if (nnode.sysctl_data == NULL) memset(own, 0, sz); else { error = sysctl_copyin(l, nnode.sysctl_data, own, sz); if (error != 0) { free(own, M_SYSCTLDATA); return (error); } } } else if ((nnode.sysctl_data != NULL) && !(flags & CTLFLAG_IMMEDIATE)) { #if NKSYMS > 0 if (name[namelen - 1] == CTL_CREATESYM) { char symname[128]; /* XXX enough? */ u_long symaddr; size_t symlen; error = sysctl_copyinstr(l, nnode.sysctl_data, symname, sizeof(symname), &symlen); if (error) return (error); error = ksyms_getval(NULL, symname, &symaddr, KSYMS_EXTERN); if (error) return (error); /* EINVAL? */ nnode.sysctl_data = (void*)symaddr; } #endif /* NKSYMS > 0 */ /* * Ideally, we'd like to verify here * that this address is acceptable, * but... * * - it might be valid now, only to * become invalid later * * - it might be invalid only for the * moment and valid later * * - or something else. * * Since we can't get a good answer, * we'll just accept the address as * given, and fault on individual * lookups. */ } } else if (nnode.sysctl_func == NULL) return (EINVAL); } /* * a process can't assign a function to a node, and the kernel * can't create a node that has no function or data. * (XXX somewhat redundant check) */ if (l != NULL || nnode.sysctl_func == NULL) { if (type != CTLTYPE_NODE && !(flags & CTLFLAG_IMMEDIATE) && nnode.sysctl_data == NULL && own == NULL) return (EINVAL); } #ifdef SYSCTL_DISALLOW_KWRITE /* * a process can't create a writable node unless it refers to * new data. */ if (l != NULL && own == NULL && type != CTLTYPE_NODE && (flags & CTLFLAG_READWRITE) != CTLFLAG_READONLY && !(flags & CTLFLAG_IMMEDIATE)) return (EPERM); #endif /* SYSCTL_DISALLOW_KWRITE */ /* * make sure there's somewhere to put the new stuff. */ if (pnode->sysctl_child == NULL) { if (flags & CTLFLAG_ANYNUMBER) error = sysctl_alloc(pnode, 1); else error = sysctl_alloc(pnode, 0); if (error) { if (own != NULL) free(own, M_SYSCTLDATA); return (error); } } node = pnode->sysctl_child; /* * no collisions, so pick a good dynamic number if we need to. */ if (nm == CTL_CREATE) { nm = ++sysctl_root.sysctl_num; for (ni = 0; ni < pnode->sysctl_clen; ni++) { if (nm == node[ni].sysctl_num) { nm++; ni = -1; } else if (nm > node[ni].sysctl_num) at = ni + 1; } } /* * oops...ran out of space */ if (pnode->sysctl_clen == pnode->sysctl_csize) { error = sysctl_realloc(pnode); if (error) { if (own != NULL) free(own, M_SYSCTLDATA); return (error); } node = pnode->sysctl_child; } /* * insert new node data */ if (at < pnode->sysctl_clen) { int t; /* * move the nodes that should come after the new one */ memmove(&node[at + 1], &node[at], (pnode->sysctl_clen - at) * sizeof(struct sysctlnode)); memset(&node[at], 0, sizeof(struct sysctlnode)); node[at].sysctl_parent = pnode; /* * and...reparent any children of any moved nodes */ for (ni = at; ni <= pnode->sysctl_clen; ni++) if (node[ni].sysctl_child != NULL) for (t = 0; t < node[ni].sysctl_csize; t++) node[ni].sysctl_child[t].sysctl_parent = &node[ni]; } node = &node[at]; pnode->sysctl_clen++; strlcpy(node->sysctl_name, nnode.sysctl_name, sizeof(node->sysctl_name)); node->sysctl_num = nm; node->sysctl_size = sz; node->sysctl_flags = SYSCTL_VERSION|type|flags; /* XXX other trees */ node->sysctl_csize = 0; node->sysctl_clen = 0; if (own) { node->sysctl_data = own; node->sysctl_flags |= CTLFLAG_OWNDATA; } else if (flags & CTLFLAG_ALIAS) { node->sysctl_alias = anum; } else if (flags & CTLFLAG_IMMEDIATE) { switch (type) { case CTLTYPE_BOOL: node->sysctl_bdata = nnode.sysctl_bdata; break; case CTLTYPE_INT: node->sysctl_idata = nnode.sysctl_idata; break; case CTLTYPE_QUAD: node->sysctl_qdata = nnode.sysctl_qdata; break; } } else { node->sysctl_data = nnode.sysctl_data; node->sysctl_flags &= ~CTLFLAG_OWNDATA; } node->sysctl_func = nnode.sysctl_func; node->sysctl_child = NULL; /* node->sysctl_parent should already be done */ /* * update "version" on path to "root" */ for (; rnode->sysctl_parent != NULL; rnode = rnode->sysctl_parent) ; pnode = node; for (nm = rnode->sysctl_ver + 1; pnode != NULL; pnode = pnode->sysctl_parent) pnode->sysctl_ver = nm; /* If this fails, the node is already added - the user won't know! */ error = sysctl_cvt_out(l, v, node, oldp, *oldlenp, oldlenp); return (error); } /* * ******************************************************************** * A wrapper around sysctl_create() that prints the thing we're trying * to add. * ******************************************************************** */ #ifdef SYSCTL_DEBUG_CREATE int sysctl_create(SYSCTLFN_ARGS) { const struct sysctlnode *node; int k, v, rc, ni, nl = namelen + (name - oname); struct sysctlnode nnode; if (newp == NULL) return EINVAL; int error = sysctl_cvt_in(l, &v, newp, newlen, &nnode); if (error) return error; node = &nnode; printf("namelen %d (", nl); for (ni = 0; ni < nl - 1; ni++) printf(" %d", oname[ni]); printf(" %d )\t[%s]\tflags %08x (%08x %d %zu)\n", k = node->sysctl_num, node->sysctl_name, node->sysctl_flags, SYSCTL_FLAGS(node->sysctl_flags), SYSCTL_TYPE(node->sysctl_flags), node->sysctl_size); node = rnode; rc = _sysctl_create(SYSCTLFN_CALL(rnode)); printf("sysctl_create("); for (ni = 0; ni < nl - 1; ni++) printf(" %d", oname[ni]); printf(" %d ) returned %d\n", k, rc); return (rc); } #endif /* SYSCTL_DEBUG_CREATE */ /* * sysctl_destroy -- Removes a node (as described by newp) from the * given tree, returning (if successful) a copy of the dead node in * oldp. Since we're removing stuff, there's not much to check. */ int sysctl_destroy(SYSCTLFN_ARGS) { struct sysctlnode *node, *pnode, onode, nnode; int ni, error, v; KASSERT(rw_write_held(&sysctl_treelock)); if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_destroy: rnode %p wrong version\n", rnode); return (EINVAL); } error = 0; if (namelen != 1 || name[namelen - 1] != CTL_DESTROY) return (EINVAL); /* * processes can only destroy nodes at securelevel 0, must be * root, and can't remove nodes from a parent that's not * writeable */ if (l != NULL) { #ifndef SYSCTL_DISALLOW_CREATE error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_DELETE, NULL, NULL, NULL); if (error) return (error); if (!(rnode->sysctl_flags & CTLFLAG_READWRITE)) #endif /* SYSCTL_DISALLOW_CREATE */ return (EPERM); } /* * nothing can remove a node if: * the node is permanent (checked later) or * the tree itself is not writeable or * the entire sysctl system is not writeable * * note that we ignore whether setup is complete or not, * because these rules always apply. */ if (!(sysctl_rootof(rnode)->sysctl_flags & CTLFLAG_READWRITE) || !(sysctl_root.sysctl_flags & CTLFLAG_READWRITE)) return (EPERM); if (newp == NULL) return (EINVAL); error = sysctl_cvt_in(l, &v, newp, newlen, &nnode); if (error) return (error); memset(&onode, 0, sizeof(struct sysctlnode)); node = rnode->sysctl_child; for (ni = 0; ni < rnode->sysctl_clen; ni++) { if (nnode.sysctl_num == node[ni].sysctl_num) { /* * if name specified, must match */ if (nnode.sysctl_name[0] != '\0' && strcmp(nnode.sysctl_name, node[ni].sysctl_name)) continue; /* * if version specified, must match */ if (nnode.sysctl_ver != 0 && nnode.sysctl_ver != node[ni].sysctl_ver) continue; /* * this must be the one */ break; } } if (ni == rnode->sysctl_clen) return (ENOENT); node = &node[ni]; pnode = node->sysctl_parent; /* * if the kernel says permanent, it is, so there. nyah. */ if (SYSCTL_FLAGS(node->sysctl_flags) & CTLFLAG_PERMANENT) return (EPERM); /* * can't delete non-empty nodes */ if (SYSCTL_TYPE(node->sysctl_flags) == CTLTYPE_NODE && node->sysctl_clen != 0) return (ENOTEMPTY); /* * if the node "owns" data, release it now */ if (node->sysctl_flags & CTLFLAG_OWNDATA) { if (node->sysctl_data != NULL) free(node->sysctl_data, M_SYSCTLDATA); node->sysctl_data = NULL; } if (node->sysctl_flags & CTLFLAG_OWNDESC) { if (node->sysctl_desc != NULL) /*XXXUNCONST*/ free(__UNCONST(node->sysctl_desc), M_SYSCTLDATA); node->sysctl_desc = NULL; } /* * if the node to be removed is not the last one on the list, * move the remaining nodes up, and reparent any grandchildren */ onode = *node; if (ni < pnode->sysctl_clen - 1) { int t; memmove(&pnode->sysctl_child[ni], &pnode->sysctl_child[ni + 1], (pnode->sysctl_clen - ni - 1) * sizeof(struct sysctlnode)); for (; ni < pnode->sysctl_clen - 1; ni++) if (SYSCTL_TYPE(pnode->sysctl_child[ni].sysctl_flags) == CTLTYPE_NODE) for (t = 0; t < pnode->sysctl_child[ni].sysctl_clen; t++) pnode->sysctl_child[ni].sysctl_child[t]. sysctl_parent = &pnode->sysctl_child[ni]; ni = pnode->sysctl_clen - 1; node = &pnode->sysctl_child[ni]; } /* * reset the space we just vacated */ memset(node, 0, sizeof(struct sysctlnode)); node->sysctl_parent = pnode; pnode->sysctl_clen--; /* * if this parent just lost its last child, nuke the creche */ if (pnode->sysctl_clen == 0) { free(pnode->sysctl_child, M_SYSCTLNODE); pnode->sysctl_csize = 0; pnode->sysctl_child = NULL; } /* * update "version" on path to "root" */ for (; rnode->sysctl_parent != NULL; rnode = rnode->sysctl_parent) ; for (ni = rnode->sysctl_ver + 1; pnode != NULL; pnode = pnode->sysctl_parent) pnode->sysctl_ver = ni; error = sysctl_cvt_out(l, v, &onode, oldp, *oldlenp, oldlenp); return (error); } /* * sysctl_lookup -- Handles copyin/copyout of new and old values. * Partial reads are globally allowed. Only root can write to things * unless the node says otherwise. */ int sysctl_lookup(SYSCTLFN_ARGS) { int error, rw; size_t sz, len; void *d; KASSERT(rw_lock_held(&sysctl_treelock)); if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("%s: rnode %p wrong version\n", __func__, rnode); return EINVAL; } if (newlen == 0) newp = NULL; error = 0; /* * you can't "look up" a node. you can "query" it, but you * can't "look it up". */ if (SYSCTL_TYPE(rnode->sysctl_flags) == CTLTYPE_NODE || namelen != 0) { DPRINTF(("%s: can't lookup a node\n", __func__)); return EINVAL; } /* * some nodes are private, so only root can look into them. */ if (l != NULL && (rnode->sysctl_flags & CTLFLAG_PRIVATE) && (error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_PRVT, NULL, NULL, NULL)) != 0) { DPRINTF(("%s: private node\n", __func__)); return error; } /* * if a node wants to be writable according to different rules * other than "only root can write to stuff unless a flag is * set", then it needs its own function which should have been * called and not us. */ if (l != NULL && newp != NULL && !(rnode->sysctl_flags & CTLFLAG_ANYWRITE) && (error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_MODIFY, NULL, NULL, NULL)) != 0) { DPRINTF(("%s: can't modify\n", __func__)); return error; } /* * is this node supposedly writable? */ rw = (rnode->sysctl_flags & CTLFLAG_READWRITE) ? 1 : 0; /* * it appears not to be writable at this time, so if someone * tried to write to it, we must tell them to go away */ if (!rw && newp != NULL) { DPRINTF(("%s: not writable\n", __func__)); return EPERM; } /* * step one, copy out the stuff we have presently */ if (rnode->sysctl_flags & CTLFLAG_IMMEDIATE) { /* * note that we discard const here because we are * modifying the contents of the node (which is okay * because it's ours) * * It also doesn't matter which field of the union we pick. */ d = __UNCONST(&rnode->sysctl_qdata); } else d = rnode->sysctl_data; if (SYSCTL_TYPE(rnode->sysctl_flags) == CTLTYPE_STRING) sz = strlen(d) + 1; /* XXX@@@ possible fault here */ else sz = rnode->sysctl_size; if (oldp != NULL) { error = sysctl_copyout(l, d, oldp, MIN(sz, *oldlenp)); if (error) { DPRINTF(("%s: bad copyout %d\n", __func__, error)); return error; } } *oldlenp = sz; /* * are we done? */ if (newp == NULL) return 0; /* * hmm...not done. must now "copy in" new value. re-adjust * sz to maximum value (strings are "weird"). */ sz = rnode->sysctl_size; switch (SYSCTL_TYPE(rnode->sysctl_flags)) { case CTLTYPE_BOOL: { bool tmp; /* * these data must be *exactly* the same size coming * in. bool may only be true or false. */ if (newlen != sz) { DPRINTF(("%s: bad size %zu != %zu\n", __func__, newlen, sz)); return EINVAL; } error = sysctl_copyin(l, newp, &tmp, sz); if (error) break; if (tmp != true && tmp != false) { DPRINTF(("%s: tmp %d\n", __func__, tmp)); return EINVAL; } *(bool *)d = tmp; break; } case CTLTYPE_INT: case CTLTYPE_QUAD: case CTLTYPE_STRUCT: /* * these data must be *exactly* the same size coming * in. */ if (newlen != sz) goto bad_size; error = sysctl_copyin(l, newp, d, sz); rnd_add_data(NULL, d, sz, 0); break; case CTLTYPE_STRING: { /* * strings, on the other hand, can be shorter, and we * let userland be sloppy about the trailing nul. */ char *newbuf; /* * too much new string? */ if (newlen > sz) goto bad_size; /* * temporary copy of new inbound string */ len = MIN(sz, newlen); newbuf = malloc(len, M_SYSCTLDATA, M_WAITOK); if (newbuf == NULL) { DPRINTF(("%s: oomem %zu\n", __func__, len)); return ENOMEM; } error = sysctl_copyin(l, newp, newbuf, len); if (error) { free(newbuf, M_SYSCTLDATA); DPRINTF(("%s: copyin %d\n", __func__, error)); return error; } /* * did they NUL terminate it, or do we have space * left to do it ourselves? */ if (newbuf[len - 1] != '\0' && len == sz) { free(newbuf, M_SYSCTLDATA); DPRINTF(("%s: string too long\n", __func__)); return EINVAL; } /* * looks good, so pop it into place and zero the rest. */ if (len > 0) { memcpy(d, newbuf, len); rnd_add_data(NULL, d, len, 0); } if (sz != len) memset((char*)d + len, 0, sz - len); free(newbuf, M_SYSCTLDATA); break; } default: DPRINTF(("%s: bad type\n", __func__)); return EINVAL; } if (error) { DPRINTF(("%s: copyin %d\n", __func__, error)); } return error; bad_size: DPRINTF(("%s: bad size %zu > %zu\n", __func__, newlen, sz)); return EINVAL; } /* * sysctl_mmap -- Dispatches sysctl mmap requests to those nodes that * purport to handle it. This interface isn't fully fleshed out yet, * unfortunately. */ static int sysctl_mmap(SYSCTLFN_ARGS) { const struct sysctlnode *node; struct sysctlnode nnode; int error; int sysctl_num; if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_mmap: rnode %p wrong version\n", rnode); return (EINVAL); } /* * let's just pretend that didn't happen, m'kay? */ if (l == NULL) return (EPERM); /* * is this a sysctlnode description of an mmap request? */ if (newp == NULL || newlen != sizeof(struct sysctlnode)) return (EINVAL); error = sysctl_copyin(l, newp, &nnode, sizeof(nnode)); if (error) return (error); /* * does the node they asked for exist? */ if (namelen != 1) return (EOPNOTSUPP); node = rnode; sysctl_num = nnode.sysctl_num; error = sysctl_locate(l, &sysctl_num, 1, &node, NULL); if (error) return (error); /* * does this node that we have found purport to handle mmap? */ if (node->sysctl_func == NULL || !(node->sysctl_flags & CTLFLAG_MMAP)) return (EOPNOTSUPP); /* * well...okay, they asked for it. */ return ((*node->sysctl_func)(SYSCTLFN_CALL(node))); } int sysctl_describe(SYSCTLFN_ARGS) { struct sysctldesc *d; void *bf; size_t sz, left, tot; int i, error, v = -1; struct sysctlnode *node; struct sysctlnode dnode; if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_query: rnode %p wrong version\n", rnode); return (EINVAL); } if (SYSCTL_TYPE(rnode->sysctl_flags) != CTLTYPE_NODE) return (ENOTDIR); if (namelen != 1 || name[0] != CTL_DESCRIBE) return (EINVAL); /* * get ready... */ error = 0; d = bf = malloc(MAXDESCLEN, M_TEMP, M_WAITOK); if (bf == NULL) return ENOMEM; tot = 0; node = rnode->sysctl_child; left = *oldlenp; /* * no request -> all descriptions at this level * request with desc unset -> just this node * request with desc set -> set descr for this node */ if (newp != NULL) { error = sysctl_cvt_in(l, &v, newp, newlen, &dnode); if (error) goto out; if (dnode.sysctl_desc != NULL) { /* * processes cannot set descriptions above * securelevel 0. and must be root. blah * blah blah. a couple more checks are made * once we find the node we want. */ if (l != NULL) { #ifndef SYSCTL_DISALLOW_CREATE error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_DESC, NULL, NULL, NULL); if (error) goto out; #else /* SYSCTL_DISALLOW_CREATE */ error = EPERM; goto out; #endif /* SYSCTL_DISALLOW_CREATE */ } /* * find node and try to set the description on it */ for (i = 0; i < rnode->sysctl_clen; i++) if (node[i].sysctl_num == dnode.sysctl_num) break; if (i == rnode->sysctl_clen) { error = ENOENT; goto out; } node = &node[i]; /* * did the caller specify a node version? */ if (dnode.sysctl_ver != 0 && dnode.sysctl_ver != node->sysctl_ver) { error = EINVAL; goto out; } /* * okay...some rules: * (1) if setup is done and the tree is * read-only or the whole system is * read-only * (2) no one can set a description on a * permanent node (it must be set when * using createv) * (3) processes cannot *change* a description * (4) processes *can*, however, set a * description on a read-only node so that * one can be created and then described * in two steps * anything else come to mind? */ if ((sysctl_root.sysctl_flags & CTLFLAG_PERMANENT) && (!(sysctl_rootof(node)->sysctl_flags & CTLFLAG_READWRITE) || !(sysctl_root.sysctl_flags & CTLFLAG_READWRITE))) { error = EPERM; goto out; } if (node->sysctl_flags & CTLFLAG_PERMANENT) { error = EPERM; goto out; } if (l != NULL && node->sysctl_desc != NULL) { error = EPERM; goto out; } /* * right, let's go ahead. the first step is * making the description into something the * node can "own", if need be. */ if (l != NULL || dnode.sysctl_flags & CTLFLAG_OWNDESC) { char *nd, *k; k = malloc(MAXDESCLEN, M_TEMP, M_WAITOK); if (k == NULL) { error = ENOMEM; goto out; } error = sysctl_copyinstr(l, dnode.sysctl_desc, k, MAXDESCLEN, &sz); if (error) { free(k, M_TEMP); goto out; } nd = malloc(sz, M_SYSCTLDATA, M_WAITOK); if (nd == NULL) { free(k, M_TEMP); error = ENOMEM; goto out; } memcpy(nd, k, sz); dnode.sysctl_flags |= CTLFLAG_OWNDESC; dnode.sysctl_desc = nd; free(k, M_TEMP); } /* * now "release" the old description and * attach the new one. ta-da. */ if ((node->sysctl_flags & CTLFLAG_OWNDESC) && node->sysctl_desc != NULL) /*XXXUNCONST*/ free(__UNCONST(node->sysctl_desc), M_SYSCTLDATA); node->sysctl_desc = dnode.sysctl_desc; node->sysctl_flags |= (dnode.sysctl_flags & CTLFLAG_OWNDESC); /* * now we "fall out" and into the loop which * will copy the new description back out for * those interested parties */ } } /* * scan for one description or just retrieve all descriptions */ for (i = 0; i < rnode->sysctl_clen; i++) { /* * did they ask for the description of only one node? */ if (v != -1 && node[i].sysctl_num != dnode.sysctl_num) continue; /* * don't describe "private" nodes to non-suser users */ if ((node[i].sysctl_flags & CTLFLAG_PRIVATE) && (l != NULL) && !(kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_SYSCTL, KAUTH_REQ_SYSTEM_SYSCTL_PRVT, NULL, NULL, NULL))) continue; /* * is this description "valid"? */ memset(bf, 0, MAXDESCLEN); if (node[i].sysctl_desc == NULL) sz = 1; else if (copystr(node[i].sysctl_desc, &d->descr_str[0], MAXDESCLEN - sizeof(*d), &sz) != 0) { /* * erase possible partial description */ memset(bf, 0, MAXDESCLEN); sz = 1; } /* * we've got it, stuff it into the caller's buffer */ d->descr_num = node[i].sysctl_num; d->descr_ver = node[i].sysctl_ver; d->descr_len = sz; /* includes trailing nul */ sz = (char *)NEXT_DESCR(d) - (char *)d; if (oldp != NULL && left >= sz) { error = sysctl_copyout(l, d, oldp, sz); if (error) goto out; left -= sz; oldp = (void *)__sysc_desc_adv(oldp, d->descr_len); } tot += sz; /* * if we get this far with v not "unset", they asked * for a specific node and we found it */ if (v != -1) break; } /* * did we find it after all? */ if (v != -1 && tot == 0) error = ENOENT; else *oldlenp = tot; out: free(bf, M_TEMP); return (error); } /* * ******************************************************************** * Section 3: Create and destroy from inside the kernel * ******************************************************************** * sysctl_createv() and sysctl_destroyv() are simpler-to-use * interfaces for the kernel to fling new entries into the mib and rip * them out later. In the case of sysctl_createv(), the returned copy * of the node (see sysctl_create()) will be translated back into a * pointer to the actual node. * * Note that sysctl_createv() will return 0 if the create request * matches an existing node (ala mkdir -p), and that sysctl_destroyv() * will return 0 if the node to be destroyed already does not exist * (aka rm -f) or if it is a parent of other nodes. * * This allows two (or more) different subsystems to assert sub-tree * existence before populating their own nodes, and to remove their * own nodes without orphaning the others when they are done. * ******************************************************************** */ #undef sysctl_createv int sysctl_createv(struct sysctllog **log, int cflags, const struct sysctlnode **rnode, const struct sysctlnode **cnode, int flags, int type, const char *namep, const char *descr, sysctlfn func, u_quad_t qv, void *newp, size_t newlen, ...) { va_list ap; int error, ni, namelen, name[CTL_MAXNAME]; const struct sysctlnode *root, *pnode; struct sysctlnode nnode, onode, *dnode; size_t sz; const struct sysctlnode *snode __diagused; /* * where are we putting this? */ if (rnode != NULL && *rnode == NULL) { printf("sysctl_createv: rnode NULL\n"); return (EINVAL); } root = rnode ? *rnode : NULL; if (cnode != NULL) *cnode = NULL; if (cflags != 0) return (EINVAL); /* * what is it? */ flags = SYSCTL_VERSION|SYSCTL_TYPE(type)|SYSCTL_FLAGS(flags); if (log != NULL) flags &= ~CTLFLAG_PERMANENT; /* * where do we put it? */ va_start(ap, newlen); namelen = 0; error = 0; ni = -1; do { if (++ni == CTL_MAXNAME) { error = ENAMETOOLONG; break; } name[ni] = va_arg(ap, int); /* * sorry, this is not supported from here */ if (name[ni] == CTL_CREATESYM) { error = EINVAL; break; } } while (name[ni] != CTL_EOL && name[ni] != CTL_CREATE); va_end(ap); if (error) return error; namelen = ni + (name[ni] == CTL_CREATE ? 1 : 0); /* * what's it called */ if (strlcpy(nnode.sysctl_name, namep, sizeof(nnode.sysctl_name)) >= sizeof(nnode.sysctl_name)) return (ENAMETOOLONG); /* * cons up the description of the new node */ nnode.sysctl_num = name[namelen - 1]; name[namelen - 1] = CTL_CREATE; nnode.sysctl_size = newlen; nnode.sysctl_flags = flags; if (type == CTLTYPE_NODE) { nnode.sysctl_csize = 0; nnode.sysctl_clen = 0; nnode.sysctl_child = NULL; if (flags & CTLFLAG_ALIAS) nnode.sysctl_alias = qv; } else if (flags & CTLFLAG_IMMEDIATE) { switch (type) { case CTLTYPE_BOOL: nnode.sysctl_bdata = qv; break; case CTLTYPE_INT: nnode.sysctl_idata = qv; break; case CTLTYPE_QUAD: nnode.sysctl_qdata = qv; break; default: return (EINVAL); } } else { nnode.sysctl_data = newp; } nnode.sysctl_func = func; nnode.sysctl_parent = NULL; nnode.sysctl_ver = 0; /* * initialize lock state -- we need locks if the main tree has * been marked as complete, but since we could be called from * either there, or from a device driver (say, at device * insertion), or from a module (at module load time, say), we * don't really want to "wait"... */ sysctl_lock(true); /* * locate the prospective parent of the new node, and if we * find it, add the new node. */ sz = sizeof(onode); pnode = root; error = sysctl_locate(NULL, &name[0], namelen - 1, &pnode, &ni); if (error) { /* * XXX: If you are seeing this printf in early bringup * stages, perhaps your setfault is not functioning and * thus kcopy() is mis-behaving. */ printf("sysctl_createv: sysctl_locate(%s) returned %d\n", nnode.sysctl_name, error); sysctl_unlock(); return (error); } error = sysctl_create(&name[ni], namelen - ni, &onode, &sz, &nnode, sizeof(nnode), &name[0], NULL, pnode); /* * unfortunately the node we wanted to create is already * there. if the node that's already there is a reasonable * facsimile of the node we wanted to create, just pretend * (for the caller's benefit) that we managed to create the * node they wanted. */ if (error == EEXIST) { /* name is the same as requested... */ if (strcmp(nnode.sysctl_name, onode.sysctl_name) == 0 && /* they want the same function... */ nnode.sysctl_func == onode.sysctl_func && /* number is the same as requested, or... */ (nnode.sysctl_num == onode.sysctl_num || /* they didn't pick a number... */ nnode.sysctl_num == CTL_CREATE)) { /* * collision here from trying to create * something that already existed; let's give * our customers a hand and tell them they got * what they wanted. */ #ifdef SYSCTL_DEBUG_CREATE printf("cleared\n"); #endif /* SYSCTL_DEBUG_CREATE */ error = 0; } } if (error == 0 && (cnode != NULL || log != NULL || descr != NULL)) { /* * sysctl_create() gave us back a copy of the node, * but we need to know where it actually is... */ pnode = root; error = sysctl_locate(NULL, &name[0], namelen - 1, &pnode, &ni); snode = pnode; /* * manual scan of last layer so that aliased nodes * aren't followed. */ if (error == 0) { for (ni = 0; ni < pnode->sysctl_clen; ni++) if (pnode->sysctl_child[ni].sysctl_num == onode.sysctl_num) break; if (ni < pnode->sysctl_clen) pnode = &pnode->sysctl_child[ni]; else error = ENOENT; } /* * not expecting an error here, but... */ if (error == 0) { KASSERTMSG(pnode->sysctl_parent == snode, "sysctl parent mis-match pnode %s, snode %s", pnode->sysctl_name, snode->sysctl_name); if (log != NULL) sysctl_log_add(log, pnode); if (cnode != NULL) *cnode = pnode; if (descr != NULL) { /* * allow first caller to *set* a * description actually to set it * * discard const here so we can attach * the description */ dnode = __UNCONST(pnode); if (pnode->sysctl_desc != NULL) /* skip it...we've got one */; else if (flags & CTLFLAG_OWNDESC) { size_t l = strlen(descr) + 1; char *d = malloc(l, M_SYSCTLDATA, M_WAITOK); if (d != NULL) { memcpy(d, descr, l); dnode->sysctl_desc = d; dnode->sysctl_flags |= CTLFLAG_OWNDESC; } } else dnode->sysctl_desc = descr; } } else { printf("sysctl_create succeeded but node not found?!\n"); /* * confusing, but the create said it * succeeded, so... */ error = 0; } } /* * now it should be safe to release the lock state. note that * the pointer to the newly created node being passed back may * not be "good" for very long. */ sysctl_unlock(); if (error != 0) { printf("sysctl_createv: sysctl_create(%s) returned %d\n", nnode.sysctl_name, error); #if 0 if (error != ENOENT) sysctl_dump(&onode); #endif } return (error); } int sysctl_destroyv(struct sysctlnode *rnode, ...) { va_list ap; int error, name[CTL_MAXNAME], namelen, ni; const struct sysctlnode *pnode, *node; struct sysctlnode dnode, *onode; size_t sz; va_start(ap, rnode); namelen = 0; ni = 0; do { if (ni == CTL_MAXNAME) { va_end(ap); return (ENAMETOOLONG); } name[ni] = va_arg(ap, int); } while (name[ni++] != CTL_EOL); namelen = ni - 1; va_end(ap); /* * i can't imagine why we'd be destroying a node when the tree * wasn't complete, but who knows? */ sysctl_lock(true); /* * where is it? */ node = rnode; error = sysctl_locate(NULL, &name[0], namelen - 1, &node, &ni); if (error) { /* they want it gone and it's not there, so... */ sysctl_unlock(); return (error == ENOENT ? 0 : error); } /* * set up the deletion */ pnode = node; node = &dnode; memset(&dnode, 0, sizeof(dnode)); dnode.sysctl_flags = SYSCTL_VERSION; dnode.sysctl_num = name[namelen - 1]; /* * we found it, now let's nuke it */ name[namelen - 1] = CTL_DESTROY; sz = 0; error = sysctl_destroy(&name[namelen - 1], 1, NULL, &sz, node, sizeof(*node), &name[0], NULL, pnode); if (error == ENOTEMPTY) { /* * think of trying to delete "foo" when "foo.bar" * (which someone else put there) is still in * existence */ error = 0; /* * dunno who put the description there, but if this * node can ever be removed, we need to make sure the * string doesn't go out of context. that means we * need to find the node that's still there (don't use * sysctl_locate() because that follows aliasing). */ node = pnode->sysctl_child; for (ni = 0; ni < pnode->sysctl_clen; ni++) if (node[ni].sysctl_num == dnode.sysctl_num) break; node = (ni < pnode->sysctl_clen) ? &node[ni] : NULL; /* * if we found it, and this node has a description, * and this node can be released, and it doesn't * already own its own description...sigh. :) */ if (node != NULL && node->sysctl_desc != NULL && !(node->sysctl_flags & CTLFLAG_PERMANENT) && !(node->sysctl_flags & CTLFLAG_OWNDESC)) { char *d; sz = strlen(node->sysctl_desc) + 1; d = malloc(sz, M_SYSCTLDATA, M_WAITOK); if (d != NULL) { /* * discard const so that we can * re-attach the description */ memcpy(d, node->sysctl_desc, sz); onode = __UNCONST(node); onode->sysctl_desc = d; onode->sysctl_flags |= CTLFLAG_OWNDESC; } else { /* * XXX drop the description? be * afraid? don't care? */ } } } sysctl_unlock(); return (error); } /* * ******************************************************************** * Deletes an entire n-ary tree. Not recommended unless you know why * you're doing it. Personally, I don't know why you'd even think * about it. * ******************************************************************** */ void sysctl_free(struct sysctlnode *rnode) { struct sysctlnode *node, *pnode; rw_enter(&sysctl_treelock, RW_WRITER); if (rnode == NULL) rnode = &sysctl_root; if (SYSCTL_VERS(rnode->sysctl_flags) != SYSCTL_VERSION) { printf("sysctl_free: rnode %p wrong version\n", rnode); rw_exit(&sysctl_treelock); return; } pnode = rnode; node = pnode->sysctl_child; do { while (node != NULL && pnode->sysctl_csize > 0) { while (node < &pnode->sysctl_child[pnode->sysctl_clen] && (SYSCTL_TYPE(node->sysctl_flags) != CTLTYPE_NODE || node->sysctl_csize == 0)) { if (SYSCTL_FLAGS(node->sysctl_flags) & CTLFLAG_OWNDATA) { if (node->sysctl_data != NULL) { free(node->sysctl_data, M_SYSCTLDATA); node->sysctl_data = NULL; } } if (SYSCTL_FLAGS(node->sysctl_flags) & CTLFLAG_OWNDESC) { if (node->sysctl_desc != NULL) { /*XXXUNCONST*/ free(__UNCONST(node->sysctl_desc), M_SYSCTLDATA); node->sysctl_desc = NULL; } } node++; } if (node < &pnode->sysctl_child[pnode->sysctl_clen]) { pnode = node; node = node->sysctl_child; } else break; } if (pnode->sysctl_child != NULL) free(pnode->sysctl_child, M_SYSCTLNODE); pnode->sysctl_clen = 0; pnode->sysctl_csize = 0; pnode->sysctl_child = NULL; node = pnode; pnode = node->sysctl_parent; } while (pnode != NULL && node != rnode); rw_exit(&sysctl_treelock); } void sysctl_log_print(const struct sysctllog *slog) { int i, len; printf("root %p left %d size %d content", (const void *)slog->log_root, slog->log_left, slog->log_size); for (len = 0, i = slog->log_left; i < slog->log_size; i++) { switch (len) { case 0: len = -1; printf(" version %d", slog->log_num[i]); break; case -1: len = -2; printf(" type %d", slog->log_num[i]); break; case -2: len = slog->log_num[i]; printf(" len %d:", slog->log_num[i]); if (len <= 0) len = -1; break; default: len--; printf(" %d", slog->log_num[i]); break; } } printf(" end\n"); } int sysctl_log_add(struct sysctllog **logp, const struct sysctlnode *node) { const int size0 = 16; int name[CTL_MAXNAME], namelen, i; const struct sysctlnode *pnode; struct sysctllog *log; if (node->sysctl_flags & CTLFLAG_PERMANENT) return (0); if (logp == NULL) return (0); if (*logp == NULL) { log = malloc(sizeof(struct sysctllog), M_SYSCTLDATA, M_WAITOK); if (log == NULL) { /* XXX print error message? */ return (-1); } log->log_num = malloc(size0 * sizeof(int), M_SYSCTLDATA, M_WAITOK); if (log->log_num == NULL) { /* XXX print error message? */ free(log, M_SYSCTLDATA); return (-1); } memset(log->log_num, 0, size0 * sizeof(int)); log->log_root = NULL; log->log_size = size0; log->log_left = size0; *logp = log; } else log = *logp; /* * check that the root is proper. it's okay to record the * address of the root of a tree. it's the only thing that's * guaranteed not to shift around as nodes come and go. */ if (log->log_root == NULL) log->log_root = sysctl_rootof(node); else if (log->log_root != sysctl_rootof(node)) { printf("sysctl: log %p root mismatch (%p)\n", log->log_root, sysctl_rootof(node)); return (-1); } /* * we will copy out name in reverse order */ for (pnode = node, namelen = 0; pnode != NULL && !(pnode->sysctl_flags & CTLFLAG_ROOT); pnode = pnode->sysctl_parent) name[namelen++] = pnode->sysctl_num; /* * do we have space? */ if (log->log_left < (namelen + 3)) sysctl_log_realloc(log); if (log->log_left < (namelen + 3)) return (-1); /* * stuff name in, then namelen, then node type, and finally, * the version for non-node nodes. */ for (i = 0; i < namelen && i < CTL_MAXNAME; i++) log->log_num[--log->log_left] = name[i]; log->log_num[--log->log_left] = namelen; log->log_num[--log->log_left] = SYSCTL_TYPE(node->sysctl_flags); if (log->log_num[log->log_left] != CTLTYPE_NODE) log->log_num[--log->log_left] = node->sysctl_ver; else log->log_num[--log->log_left] = 0; return (0); } void sysctl_teardown(struct sysctllog **logp) { const struct sysctlnode *rnode; struct sysctlnode node; struct sysctllog *log; uint namelen; int *name, t, v, error, ni; size_t sz; if (logp == NULL || *logp == NULL) return; log = *logp; rw_enter(&sysctl_treelock, RW_WRITER); memset(&node, 0, sizeof(node)); while (log->log_left < log->log_size) { KASSERT((log->log_left + 3 < log->log_size) && (log->log_left + log->log_num[log->log_left + 2] <= log->log_size)); v = log->log_num[log->log_left++]; t = log->log_num[log->log_left++]; namelen = log->log_num[log->log_left++]; name = &log->log_num[log->log_left]; node.sysctl_num = name[namelen - 1]; node.sysctl_flags = SYSCTL_VERSION|t; node.sysctl_ver = v; rnode = log->log_root; error = sysctl_locate(NULL, &name[0], namelen, &rnode, &ni); if (error == 0) { name[namelen - 1] = CTL_DESTROY; rnode = rnode->sysctl_parent; sz = 0; (void)sysctl_destroy(&name[namelen - 1], 1, NULL, &sz, &node, sizeof(node), &name[0], NULL, rnode); } log->log_left += namelen; } KASSERT(log->log_size == log->log_left); free(log->log_num, M_SYSCTLDATA); free(log, M_SYSCTLDATA); *logp = NULL; rw_exit(&sysctl_treelock); } /* * ******************************************************************** * old_sysctl -- A routine to bridge old-style internal calls to the * new infrastructure. * ******************************************************************** */ int old_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen, struct lwp *l) { int error; size_t oldlen = 0; size_t savelen; if (oldlenp) { oldlen = *oldlenp; } savelen = oldlen; sysctl_lock(newp != NULL); error = sysctl_dispatch(name, namelen, oldp, &oldlen, newp, newlen, name, l, NULL); sysctl_unlock(); if (error == 0 && oldp != NULL && savelen < oldlen) error = ENOMEM; if (oldlenp) { *oldlenp = oldlen; } return (error); } /* * ******************************************************************** * Section 4: Generic helper routines * ******************************************************************** * "helper" routines that can do more finely grained access control, * construct structures from disparate information, create the * appearance of more nodes and sub-trees, etc. for example, if * CTL_PROC wanted a helper function, it could respond to a CTL_QUERY * with a dynamically created list of nodes that represented the * currently running processes at that instant. * ******************************************************************** */ /* * first, a few generic helpers that provide: * * sysctl_needfunc() a readonly interface that emits a warning * sysctl_notavail() returns EOPNOTSUPP (generic error) * sysctl_null() an empty return buffer with no error */ int sysctl_needfunc(SYSCTLFN_ARGS) { int error; printf("!!SYSCTL_NEEDFUNC!!\n"); if (newp != NULL || namelen != 0) return (EOPNOTSUPP); error = 0; if (oldp != NULL) error = sysctl_copyout(l, rnode->sysctl_data, oldp, MIN(rnode->sysctl_size, *oldlenp)); *oldlenp = rnode->sysctl_size; return (error); } int sysctl_notavail(SYSCTLFN_ARGS) { if (namelen == 1 && name[0] == CTL_QUERY) return (sysctl_query(SYSCTLFN_CALL(rnode))); return (EOPNOTSUPP); } int sysctl_null(SYSCTLFN_ARGS) { *oldlenp = 0; return (0); } u_int sysctl_map_flags(const u_int *map, u_int word) { u_int rv; for (rv = 0; *map != 0; map += 2) if ((word & map[0]) != 0) rv |= map[1]; return rv; } /* * ******************************************************************** * Section 5: The machinery that makes it all go * ******************************************************************** * Memory "manglement" routines. Not much to this, eh? * ******************************************************************** */ static int sysctl_alloc(struct sysctlnode *p, int x) { int i; struct sysctlnode *n; assert(p->sysctl_child == NULL); if (x == 1) n = malloc(sizeof(struct sysctlnode), M_SYSCTLNODE, M_WAITOK); else n = malloc(SYSCTL_DEFSIZE * sizeof(struct sysctlnode), M_SYSCTLNODE, M_WAITOK); if (n == NULL) return (ENOMEM); if (x == 1) { memset(n, 0, sizeof(struct sysctlnode)); p->sysctl_csize = 1; } else { memset(n, 0, SYSCTL_DEFSIZE * sizeof(struct sysctlnode)); p->sysctl_csize = SYSCTL_DEFSIZE; } p->sysctl_clen = 0; for (i = 0; i < p->sysctl_csize; i++) n[i].sysctl_parent = p; p->sysctl_child = n; return (0); } static int sysctl_realloc(struct sysctlnode *p) { int i, j, olen; struct sysctlnode *n; assert(p->sysctl_csize == p->sysctl_clen); /* * how many do we have...how many should we make? */ olen = p->sysctl_clen; n = malloc(2 * olen * sizeof(struct sysctlnode), M_SYSCTLNODE, M_WAITOK); if (n == NULL) return (ENOMEM); /* * move old children over...initialize new children */ memcpy(n, p->sysctl_child, olen * sizeof(struct sysctlnode)); memset(&n[olen], 0, olen * sizeof(struct sysctlnode)); p->sysctl_csize = 2 * olen; /* * reattach moved (and new) children to parent; if a moved * child node has children, reattach the parent pointers of * grandchildren */ for (i = 0; i < p->sysctl_csize; i++) { n[i].sysctl_parent = p; if (n[i].sysctl_child != NULL) { for (j = 0; j < n[i].sysctl_csize; j++) n[i].sysctl_child[j].sysctl_parent = &n[i]; } } /* * get out with the old and in with the new */ free(p->sysctl_child, M_SYSCTLNODE); p->sysctl_child = n; return (0); } static int sysctl_log_realloc(struct sysctllog *log) { int *n, s, d; s = log->log_size * 2; d = log->log_size; n = malloc(s * sizeof(int), M_SYSCTLDATA, M_WAITOK); if (n == NULL) return (-1); memset(n, 0, s * sizeof(int)); memcpy(&n[d], log->log_num, d * sizeof(int)); free(log->log_num, M_SYSCTLDATA); log->log_num = n; if (d) log->log_left += d; else log->log_left = s; log->log_size = s; return (0); } /* * ******************************************************************** * Section 6: Conversion between API versions wrt the sysctlnode * ******************************************************************** */ static int sysctl_cvt_in(struct lwp *l, int *vp, const void *i, size_t sz, struct sysctlnode *node) { int error, flags; if (i == NULL || sz < sizeof(flags)) return (EINVAL); error = sysctl_copyin(l, i, &flags, sizeof(flags)); if (error) return (error); #if (SYSCTL_VERSION != SYSCTL_VERS_1) #error sysctl_cvt_in: no support for SYSCTL_VERSION #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ if (sz == sizeof(*node) && SYSCTL_VERS(flags) == SYSCTL_VERSION) { error = sysctl_copyin(l, i, node, sizeof(*node)); if (error) return (error); *vp = SYSCTL_VERSION; return (0); } return (EINVAL); } static int sysctl_cvt_out(struct lwp *l, int v, const struct sysctlnode *i, void *ovp, size_t left, size_t *szp) { size_t sz = sizeof(*i); const void *src = i; int error; switch (v) { case SYSCTL_VERS_0: return (EINVAL); #if (SYSCTL_VERSION != SYSCTL_VERS_1) #error sysctl_cvt_out: no support for SYSCTL_VERSION #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ case SYSCTL_VERSION: /* nothing more to do here */ break; } if (ovp != NULL && left >= sz) { error = sysctl_copyout(l, src, ovp, sz); if (error) return (error); } if (szp != NULL) *szp = sz; return (0); } static uint8_t address_key[32]; /* key used in address hashing */ static ONCE_DECL(random_inithook); static int random_address_init(void) { cprng_strong(kern_cprng, address_key, sizeof(address_key), 0); return 0; } void hash_value(void *d, size_t ds, const void *s, size_t ss) { RUN_ONCE(&random_inithook, random_address_init); blake2s(d, ds, address_key, sizeof(address_key), s, ss); }