1 /* $NetBSD: npfext_rndblock.c,v 1.2 2018/09/29 14:41:37 rmind Exp $ */ 2 3 /*- 4 * Copyright (c) 2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __RCSID("$NetBSD: npfext_rndblock.c,v 1.2 2018/09/29 14:41:37 rmind Exp $"); 31 32 #include <stdlib.h> 33 #include <stdbool.h> 34 #include <string.h> 35 #include <assert.h> 36 #include <errno.h> 37 38 #include <npf.h> 39 40 int npfext_rndblock_init(void); 41 nl_ext_t * npfext_rndblock_construct(const char *); 42 int npfext_rndblock_param(nl_ext_t *, const char *, const char *); 43 44 int 45 npfext_rndblock_init(void) 46 { 47 /* Nothing to initialise. */ 48 return 0; 49 } 50 51 nl_ext_t * 52 npfext_rndblock_construct(const char *name) 53 { 54 assert(strcmp(name, "rndblock") == 0); 55 return npf_ext_construct(name); 56 } 57 58 int 59 npfext_rndblock_param(nl_ext_t *ext, const char *param, const char *val) 60 { 61 enum ptype { PARAM_U32 }; 62 static const struct param { 63 const char * name; 64 enum ptype type; 65 signed long min; 66 signed long max; 67 } params[] = { 68 { "mod", PARAM_U32, 1, LONG_MAX }, 69 { "percentage", PARAM_U32, 1, 9999 }, 70 }; 71 72 if (val == NULL) { 73 return EINVAL; 74 } 75 for (unsigned i = 0; i < __arraycount(params); i++) { 76 const char *name = params[i].name; 77 long ival; 78 79 if (strcmp(name, param) != 0) { 80 continue; 81 } 82 83 /* 84 * Note: multiply by 100 and convert floating point to 85 * an integer, as 100% is based on 10000 in the kernel. 86 */ 87 ival = (i == 1) ? atof(val) * 100 : atol(val); 88 if (ival < params[i].min || ival > params[i].max) { 89 return EINVAL; 90 } 91 assert(params[i].type == PARAM_U32); 92 npf_ext_param_u32(ext, name, ival); 93 return 0; 94 } 95 96 /* Invalid parameter, if not found. */ 97 return EINVAL; 98 } 99