rwfile.c revision 259065
1/*- 2 * Copyright (c) 2013 Mark R V Murray 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: releng/10.0/sys/dev/random/rwfile.c 256381 2013-10-12 15:31:36Z markm $"); 30 31#include "opt_random.h" 32 33#ifdef RANDOM_RWFILE 34 35#include <sys/param.h> 36#include <sys/systm.h> 37#include <sys/kernel.h> 38#include <sys/proc.h> 39#include <sys/namei.h> 40#include <sys/fcntl.h> 41#include <sys/vnode.h> 42 43#include <dev/random/rwfile.h> 44 45int 46randomdev_read_file(const char *filename, void *buf, size_t length) 47{ 48 struct nameidata nd; 49 struct thread* td = curthread; 50 int error; 51 ssize_t resid; 52 int flags; 53 54 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 55 flags = FREAD; 56 error = vn_open(&nd, &flags, 0, NULL); 57 if (error == 0) { 58 NDFREE(&nd, NDF_ONLY_PNBUF); 59 if (nd.ni_vp->v_type != VREG) 60 error = ENOEXEC; 61 else 62 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, length, 0, UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td); 63 VOP_UNLOCK(nd.ni_vp, 0); 64 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 65 } 66 67 return (error); 68} 69 70int 71randomdev_write_file(const char *filename, void *buf, size_t length) 72{ 73 struct nameidata nd; 74 struct thread* td = curthread; 75 int error; 76 ssize_t resid; 77 int flags; 78 79 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 80 flags = FWRITE | O_CREAT | O_TRUNC; 81 error = vn_open(&nd, &flags, 0, NULL); 82 if (error == 0) { 83 NDFREE(&nd, NDF_ONLY_PNBUF); 84 if (nd.ni_vp->v_type != VREG) 85 error = ENOEXEC; 86 else 87 error = vn_rdwr(UIO_WRITE, nd.ni_vp, buf, length, 0, UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td); 88 89 VOP_UNLOCK(nd.ni_vp, 0); 90 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 91 } 92 93 return (error); 94} 95 96#endif 97