1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <alloca.h> 29 #include <errno.h> 30 #include <stdio.h> 31 #include <string.h> 32 #include <sys/lx_syscall.h> 33 #include <sys/lx_misc.h> 34 #include <sys/lx_debug.h> 35 36 /* 37 * sysctl() implementation. The full set of possible values is incredibly 38 * large; we only implement the bare minimum here, namely basic kernel 39 * information. 40 * 41 * For the moment, we also print out debugging messages if the application 42 * attempts to write or access any other values, so we can tell if we are not 43 * supporting something we should be. 44 */ 45 46 struct lx_sysctl_args { 47 int *name; 48 int nlen; 49 void *oldval; 50 size_t *oldlenp; 51 void *newval; 52 size_t newlen; 53 }; 54 55 #define LX_CTL_KERN 1 56 57 #define LX_KERN_OSTYPE 1 58 #define LX_KERN_OSRELEASE 2 59 #define LX_KERN_OSREV 3 60 #define LX_KERN_VERSION 4 61 62 int 63 lx_sysctl(uintptr_t raw) 64 { 65 struct lx_sysctl_args args; 66 int name[2]; 67 size_t oldlen; 68 char *namebuf; 69 70 if (uucopy((void *)raw, &args, sizeof (args)) < 0) 71 return (-EFAULT); 72 73 /* 74 * We only allow [ CTL_KERN, KERN_* ] pairs, so reject anything that 75 * doesn't have exactly two values starting with LX_CTL_KERN. 76 */ 77 if (args.nlen != 2) 78 return (-ENOTDIR); 79 80 if (uucopy(args.name, name, sizeof (name)) < 0) 81 return (-EFAULT); 82 83 if (name[0] != LX_CTL_KERN) { 84 lx_debug("sysctl: read of [%d, %d] unsupported", 85 name[0], name[1]); 86 return (-ENOTDIR); 87 } 88 89 /* We don't support writing new sysctl values. */ 90 if ((args.newval != NULL) || (args.newlen != 0)) { 91 lx_debug("sysctl: write of [%d, %d] unsupported", 92 name[0], name[1]); 93 return (-EPERM); 94 } 95 96 /* 97 * It may seem silly, but passing in a NULL oldval pointer and not 98 * writing any new values is a perfectly legal thing to do and should 99 * succeed. 100 */ 101 if (args.oldval == NULL) 102 return (0); 103 104 /* 105 * Likewise, Linux specifies that setting a non-NULL oldval but a 106 * zero *oldlenp should result in an errno of EFAULT. 107 */ 108 if ((uucopy(args.oldlenp, &oldlen, sizeof (oldlen)) < 0) || 109 (oldlen == 0)) 110 return (-EFAULT); 111 112 namebuf = SAFE_ALLOCA(oldlen); 113 if (namebuf == NULL) 114 return (-ENOMEM); 115 116 switch (name[1]) { 117 case LX_KERN_OSTYPE: 118 (void) strlcpy(namebuf, LX_UNAME_SYSNAME, oldlen); 119 break; 120 case LX_KERN_OSRELEASE: 121 (void) strlcpy(namebuf, lx_release, oldlen); 122 break; 123 case LX_KERN_VERSION: 124 (void) strlcpy(namebuf, LX_UNAME_VERSION, oldlen); 125 break; 126 default: 127 lx_debug("sysctl: read of [CTL_KERN, %d] unsupported", name[1]); 128 return (-ENOTDIR); 129 } 130 131 oldlen = strlen(namebuf); 132 133 if ((uucopy(namebuf, args.oldval, oldlen) < 0) || 134 (uucopy(&oldlen, args.oldlenp, sizeof (oldlen)) < 0)) 135 return (-EFAULT); 136 137 return (0); 138 }