| 1 | /* $NetBSD: kern_ktrace_vfs.c,v 1.2 2014/09/05 09:20:59 matt Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Andrew Doran. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | /* |
| 33 | * Copyright (c) 1989, 1993 |
| 34 | * The Regents of the University of California. All rights reserved. |
| 35 | * |
| 36 | * Redistribution and use in source and binary forms, with or without |
| 37 | * modification, are permitted provided that the following conditions |
| 38 | * are met: |
| 39 | * 1. Redistributions of source code must retain the above copyright |
| 40 | * notice, this list of conditions and the following disclaimer. |
| 41 | * 2. Redistributions in binary form must reproduce the above copyright |
| 42 | * notice, this list of conditions and the following disclaimer in the |
| 43 | * documentation and/or other materials provided with the distribution. |
| 44 | * 3. Neither the name of the University nor the names of its contributors |
| 45 | * may be used to endorse or promote products derived from this software |
| 46 | * without specific prior written permission. |
| 47 | * |
| 48 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 49 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 50 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 51 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 52 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 53 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 54 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 55 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 56 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 57 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 58 | * SUCH DAMAGE. |
| 59 | * |
| 60 | * @(#)kern_ktrace.c 8.5 (Berkeley) 5/14/95 |
| 61 | */ |
| 62 | |
| 63 | #include <sys/cdefs.h> |
| 64 | __KERNEL_RCSID(0, "$NetBSD: kern_ktrace_vfs.c,v 1.2 2014/09/05 09:20:59 matt Exp $" ); |
| 65 | |
| 66 | #include <sys/param.h> |
| 67 | #include <sys/systm.h> |
| 68 | #include <sys/file.h> |
| 69 | #include <sys/filedesc.h> |
| 70 | #include <sys/namei.h> |
| 71 | #include <sys/vnode.h> |
| 72 | #include <sys/kernel.h> |
| 73 | #include <sys/ktrace.h> |
| 74 | #include <sys/kauth.h> |
| 75 | |
| 76 | #include <sys/mount.h> |
| 77 | #include <sys/syscallargs.h> |
| 78 | |
| 79 | /* |
| 80 | * ktrace system call, the part of the ktrace framework that |
| 81 | * explicitly interacts with VFS |
| 82 | */ |
| 83 | /* ARGSUSED */ |
| 84 | int |
| 85 | sys_ktrace(struct lwp *l, const struct sys_ktrace_args *uap, register_t *retval) |
| 86 | { |
| 87 | /* { |
| 88 | syscallarg(const char *) fname; |
| 89 | syscallarg(int) ops; |
| 90 | syscallarg(int) facs; |
| 91 | syscallarg(int) pid; |
| 92 | } */ |
| 93 | struct vnode *vp = NULL; |
| 94 | file_t *fp = NULL; |
| 95 | struct pathbuf *pb; |
| 96 | struct nameidata nd; |
| 97 | int error = 0; |
| 98 | int fd; |
| 99 | |
| 100 | if (ktrenter(l)) |
| 101 | return EAGAIN; |
| 102 | |
| 103 | if (KTROP(SCARG(uap, ops)) != KTROP_CLEAR) { |
| 104 | /* |
| 105 | * an operation which requires a file argument. |
| 106 | */ |
| 107 | error = pathbuf_copyin(SCARG(uap, fname), &pb); |
| 108 | if (error) { |
| 109 | ktrexit(l); |
| 110 | return (error); |
| 111 | } |
| 112 | NDINIT(&nd, LOOKUP, FOLLOW, pb); |
| 113 | if ((error = vn_open(&nd, FREAD|FWRITE, 0)) != 0) { |
| 114 | pathbuf_destroy(pb); |
| 115 | ktrexit(l); |
| 116 | return (error); |
| 117 | } |
| 118 | vp = nd.ni_vp; |
| 119 | pathbuf_destroy(pb); |
| 120 | VOP_UNLOCK(vp); |
| 121 | if (vp->v_type != VREG) { |
| 122 | vn_close(vp, FREAD|FWRITE, l->l_cred); |
| 123 | ktrexit(l); |
| 124 | return (EACCES); |
| 125 | } |
| 126 | /* |
| 127 | * This uses up a file descriptor slot in the |
| 128 | * tracing process for the duration of this syscall. |
| 129 | * This is not expected to be a problem. |
| 130 | */ |
| 131 | if ((error = fd_allocfile(&fp, &fd)) != 0) { |
| 132 | vn_close(vp, FWRITE, l->l_cred); |
| 133 | ktrexit(l); |
| 134 | return error; |
| 135 | } |
| 136 | fp->f_flag = FWRITE; |
| 137 | fp->f_type = DTYPE_VNODE; |
| 138 | fp->f_ops = &vnops; |
| 139 | fp->f_vnode = vp; |
| 140 | vp = NULL; |
| 141 | } |
| 142 | error = ktrace_common(l, SCARG(uap, ops), SCARG(uap, facs), |
| 143 | SCARG(uap, pid), &fp); |
| 144 | if (KTROP(SCARG(uap, ops)) != KTROP_CLEAR) |
| 145 | fd_abort(curproc, fp, fd); |
| 146 | return (error); |
| 147 | } |
| 148 | |