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
npfext_rndblock_init(void)45 npfext_rndblock_init(void)
46 {
47 /* Nothing to initialise. */
48 return 0;
49 }
50
51 nl_ext_t *
npfext_rndblock_construct(const char * name)52 npfext_rndblock_construct(const char *name)
53 {
54 assert(strcmp(name, "rndblock") == 0);
55 return npf_ext_construct(name);
56 }
57
58 int
npfext_rndblock_param(nl_ext_t * ext,const char * param,const char * val)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