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1/*
2 * Module for modifying the secmark field of the skb, for use by
3 * security subsystems.
4 *
5 * Based on the nfmark match by:
6 * (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
7 *
8 * (C) 2006,2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 */
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16#include <linux/module.h>
17#include <linux/security.h>
18#include <linux/skbuff.h>
19#include <linux/netfilter/x_tables.h>
20#include <linux/netfilter/xt_SECMARK.h>
21
22MODULE_LICENSE("GPL");
23MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
24MODULE_DESCRIPTION("Xtables: packet security mark modification");
25MODULE_ALIAS("ipt_SECMARK");
26MODULE_ALIAS("ip6t_SECMARK");
27
28#define PFX "SECMARK: "
29
30static u8 mode;
31
32static unsigned int
33secmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
34{
35 u32 secmark = 0;
36 const struct xt_secmark_target_info *info = par->targinfo;
37
38 BUG_ON(info->mode != mode);
39
40 switch (mode) {
41 case SECMARK_MODE_SEL:
42 secmark = info->secid;
43 break;
44 default:
45 BUG();
46 }
47
48 skb->secmark = secmark;
49 return XT_CONTINUE;
50}
51
52static int checkentry_lsm(struct xt_secmark_target_info *info)
53{
54 int err;
55
56 info->secctx[SECMARK_SECCTX_MAX - 1] = '\0';
57 info->secid = 0;
58
59 err = security_secctx_to_secid(info->secctx, strlen(info->secctx),
60 &info->secid);
61 if (err) {
62 if (err == -EINVAL)
63 pr_info("invalid security context \'%s\'\n", info->secctx);
64 return err;
65 }
66
67 if (!info->secid) {
68 pr_info("unable to map security context \'%s\'\n", info->secctx);
69 return -ENOENT;
70 }
71
72 err = security_secmark_relabel_packet(info->secid);
73 if (err) {
74 pr_info("unable to obtain relabeling permission\n");
75 return err;
76 }
77
78 security_secmark_refcount_inc();
79 return 0;
80}
81
82static int secmark_tg_check(const struct xt_tgchk_param *par)
83{
84 struct xt_secmark_target_info *info = par->targinfo;
85 int err;
86
87 if (strcmp(par->table, "mangle") != 0 &&
88 strcmp(par->table, "security") != 0) {
89 pr_info("target only valid in the \'mangle\' "
90 "or \'security\' tables, not \'%s\'.\n", par->table);
91 return -EINVAL;
92 }
93
94 if (mode && mode != info->mode) {
95 pr_info("mode already set to %hu cannot mix with "
96 "rules for mode %hu\n", mode, info->mode);
97 return -EINVAL;
98 }
99
100 switch (info->mode) {
101 case SECMARK_MODE_SEL:
102 break;
103 default:
104 pr_info("invalid mode: %hu\n", info->mode);
105 return -EINVAL;
106 }
107
108 err = checkentry_lsm(info);
109 if (err)
110 return err;
111
112 if (!mode)
113 mode = info->mode;
114 return 0;
115}
116
117static void secmark_tg_destroy(const struct xt_tgdtor_param *par)
118{
119 switch (mode) {
120 case SECMARK_MODE_SEL:
121 security_secmark_refcount_dec();
122 }
123}
124
125static struct xt_target secmark_tg_reg __read_mostly = {
126 .name = "SECMARK",
127 .revision = 0,
128 .family = NFPROTO_UNSPEC,
129 .checkentry = secmark_tg_check,
130 .destroy = secmark_tg_destroy,
131 .target = secmark_tg,
132 .targetsize = sizeof(struct xt_secmark_target_info),
133 .me = THIS_MODULE,
134};
135
136static int __init secmark_tg_init(void)
137{
138 return xt_register_target(&secmark_tg_reg);
139}
140
141static void __exit secmark_tg_exit(void)
142{
143 xt_unregister_target(&secmark_tg_reg);
144}
145
146module_init(secmark_tg_init);
147module_exit(secmark_tg_exit);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Module for modifying the secmark field of the skb, for use by
4 * security subsystems.
5 *
6 * Based on the nfmark match by:
7 * (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
8 *
9 * (C) 2006,2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
10 */
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12#include <linux/module.h>
13#include <linux/security.h>
14#include <linux/skbuff.h>
15#include <linux/netfilter/x_tables.h>
16#include <linux/netfilter/xt_SECMARK.h>
17
18MODULE_LICENSE("GPL");
19MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
20MODULE_DESCRIPTION("Xtables: packet security mark modification");
21MODULE_ALIAS("ipt_SECMARK");
22MODULE_ALIAS("ip6t_SECMARK");
23
24#define PFX "SECMARK: "
25
26static u8 mode;
27
28static unsigned int
29secmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
30{
31 u32 secmark = 0;
32 const struct xt_secmark_target_info *info = par->targinfo;
33
34 switch (mode) {
35 case SECMARK_MODE_SEL:
36 secmark = info->secid;
37 break;
38 default:
39 BUG();
40 }
41
42 skb->secmark = secmark;
43 return XT_CONTINUE;
44}
45
46static int checkentry_lsm(struct xt_secmark_target_info *info)
47{
48 int err;
49
50 info->secctx[SECMARK_SECCTX_MAX - 1] = '\0';
51 info->secid = 0;
52
53 err = security_secctx_to_secid(info->secctx, strlen(info->secctx),
54 &info->secid);
55 if (err) {
56 if (err == -EINVAL)
57 pr_info_ratelimited("invalid security context \'%s\'\n",
58 info->secctx);
59 return err;
60 }
61
62 if (!info->secid) {
63 pr_info_ratelimited("unable to map security context \'%s\'\n",
64 info->secctx);
65 return -ENOENT;
66 }
67
68 err = security_secmark_relabel_packet(info->secid);
69 if (err) {
70 pr_info_ratelimited("unable to obtain relabeling permission\n");
71 return err;
72 }
73
74 security_secmark_refcount_inc();
75 return 0;
76}
77
78static int secmark_tg_check(const struct xt_tgchk_param *par)
79{
80 struct xt_secmark_target_info *info = par->targinfo;
81 int err;
82
83 if (strcmp(par->table, "mangle") != 0 &&
84 strcmp(par->table, "security") != 0) {
85 pr_info_ratelimited("only valid in \'mangle\' or \'security\' table, not \'%s\'\n",
86 par->table);
87 return -EINVAL;
88 }
89
90 if (mode && mode != info->mode) {
91 pr_info_ratelimited("mode already set to %hu cannot mix with rules for mode %hu\n",
92 mode, info->mode);
93 return -EINVAL;
94 }
95
96 switch (info->mode) {
97 case SECMARK_MODE_SEL:
98 break;
99 default:
100 pr_info_ratelimited("invalid mode: %hu\n", info->mode);
101 return -EINVAL;
102 }
103
104 err = checkentry_lsm(info);
105 if (err)
106 return err;
107
108 if (!mode)
109 mode = info->mode;
110 return 0;
111}
112
113static void secmark_tg_destroy(const struct xt_tgdtor_param *par)
114{
115 switch (mode) {
116 case SECMARK_MODE_SEL:
117 security_secmark_refcount_dec();
118 }
119}
120
121static struct xt_target secmark_tg_reg __read_mostly = {
122 .name = "SECMARK",
123 .revision = 0,
124 .family = NFPROTO_UNSPEC,
125 .checkentry = secmark_tg_check,
126 .destroy = secmark_tg_destroy,
127 .target = secmark_tg,
128 .targetsize = sizeof(struct xt_secmark_target_info),
129 .me = THIS_MODULE,
130};
131
132static int __init secmark_tg_init(void)
133{
134 return xt_register_target(&secmark_tg_reg);
135}
136
137static void __exit secmark_tg_exit(void)
138{
139 xt_unregister_target(&secmark_tg_reg);
140}
141
142module_init(secmark_tg_init);
143module_exit(secmark_tg_exit);