1 /* Copyright (C) 2014 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 as
5 * published by the Free Software Foundation.
6 */
7
8 /* Kernel module implementing an IP set type: the hash:mac type */
9
10 #include <linux/jhash.h>
11 #include <linux/module.h>
12 #include <linux/etherdevice.h>
13 #include <linux/skbuff.h>
14 #include <linux/errno.h>
15 #include <linux/if_ether.h>
16 #include <net/netlink.h>
17
18 #include <linux/netfilter.h>
19 #include <linux/netfilter/ipset/ip_set.h>
20 #include <linux/netfilter/ipset/ip_set_hash.h>
21
22 #define IPSET_TYPE_REV_MIN 0
23 #define IPSET_TYPE_REV_MAX 0
24
25 MODULE_LICENSE("GPL");
26 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
27 IP_SET_MODULE_DESC("hash:mac", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
28 MODULE_ALIAS("ip_set_hash:mac");
29
30 /* Type specific function prefix */
31 #define HTYPE hash_mac
32
33 /* Member elements */
34 struct hash_mac4_elem {
35 /* Zero valued IP addresses cannot be stored */
36 union {
37 unsigned char ether[ETH_ALEN];
38 __be32 foo[2];
39 };
40 };
41
42 /* Common functions */
43
44 static inline bool
hash_mac4_data_equal(const struct hash_mac4_elem * e1,const struct hash_mac4_elem * e2,u32 * multi)45 hash_mac4_data_equal(const struct hash_mac4_elem *e1,
46 const struct hash_mac4_elem *e2,
47 u32 *multi)
48 {
49 return ether_addr_equal(e1->ether, e2->ether);
50 }
51
52 static inline bool
hash_mac4_data_list(struct sk_buff * skb,const struct hash_mac4_elem * e)53 hash_mac4_data_list(struct sk_buff *skb, const struct hash_mac4_elem *e)
54 {
55 if (nla_put(skb, IPSET_ATTR_ETHER, ETH_ALEN, e->ether))
56 goto nla_put_failure;
57 return false;
58
59 nla_put_failure:
60 return true;
61 }
62
63 static inline void
hash_mac4_data_next(struct hash_mac4_elem * next,const struct hash_mac4_elem * e)64 hash_mac4_data_next(struct hash_mac4_elem *next,
65 const struct hash_mac4_elem *e)
66 {
67 }
68
69 #define MTYPE hash_mac4
70 #define HOST_MASK 32
71 #define IP_SET_EMIT_CREATE
72 #define IP_SET_PROTO_UNDEF
73 #include "ip_set_hash_gen.h"
74
75 static int
hash_mac4_kadt(struct ip_set * set,const struct sk_buff * skb,const struct xt_action_param * par,enum ipset_adt adt,struct ip_set_adt_opt * opt)76 hash_mac4_kadt(struct ip_set *set, const struct sk_buff *skb,
77 const struct xt_action_param *par,
78 enum ipset_adt adt, struct ip_set_adt_opt *opt)
79 {
80 ipset_adtfn adtfn = set->variant->adt[adt];
81 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
82 struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
83
84 /* MAC can be src only */
85 if (!(opt->flags & IPSET_DIM_ONE_SRC))
86 return 0;
87
88 if (skb_mac_header(skb) < skb->head ||
89 (skb_mac_header(skb) + ETH_HLEN) > skb->data)
90 return -EINVAL;
91
92 ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
93 if (is_zero_ether_addr(e.ether))
94 return -EINVAL;
95 return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
96 }
97
98 static int
hash_mac4_uadt(struct ip_set * set,struct nlattr * tb[],enum ipset_adt adt,u32 * lineno,u32 flags,bool retried)99 hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[],
100 enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
101 {
102 ipset_adtfn adtfn = set->variant->adt[adt];
103 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
104 struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
105 int ret;
106
107 if (tb[IPSET_ATTR_LINENO])
108 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
109
110 if (unlikely(!tb[IPSET_ATTR_ETHER] ||
111 nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN))
112 return -IPSET_ERR_PROTOCOL;
113
114 ret = ip_set_get_extensions(set, tb, &ext);
115 if (ret)
116 return ret;
117 ether_addr_copy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]));
118 if (is_zero_ether_addr(e.ether))
119 return -IPSET_ERR_HASH_ELEM;
120
121 return adtfn(set, &e, &ext, &ext, flags);
122 }
123
124 static struct ip_set_type hash_mac_type __read_mostly = {
125 .name = "hash:mac",
126 .protocol = IPSET_PROTOCOL,
127 .features = IPSET_TYPE_MAC,
128 .dimension = IPSET_DIM_ONE,
129 .family = NFPROTO_UNSPEC,
130 .revision_min = IPSET_TYPE_REV_MIN,
131 .revision_max = IPSET_TYPE_REV_MAX,
132 .create = hash_mac_create,
133 .create_policy = {
134 [IPSET_ATTR_HASHSIZE] = { .type = NLA_U32 },
135 [IPSET_ATTR_MAXELEM] = { .type = NLA_U32 },
136 [IPSET_ATTR_PROBES] = { .type = NLA_U8 },
137 [IPSET_ATTR_RESIZE] = { .type = NLA_U8 },
138 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
139 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
140 },
141 .adt_policy = {
142 [IPSET_ATTR_ETHER] = { .type = NLA_BINARY,
143 .len = ETH_ALEN },
144 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
145 [IPSET_ATTR_LINENO] = { .type = NLA_U32 },
146 [IPSET_ATTR_BYTES] = { .type = NLA_U64 },
147 [IPSET_ATTR_PACKETS] = { .type = NLA_U64 },
148 [IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING,
149 .len = IPSET_MAX_COMMENT_SIZE },
150 [IPSET_ATTR_SKBMARK] = { .type = NLA_U64 },
151 [IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 },
152 [IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 },
153 },
154 .me = THIS_MODULE,
155 };
156
157 static int __init
hash_mac_init(void)158 hash_mac_init(void)
159 {
160 return ip_set_type_register(&hash_mac_type);
161 }
162
163 static void __exit
hash_mac_fini(void)164 hash_mac_fini(void)
165 {
166 rcu_barrier();
167 ip_set_type_unregister(&hash_mac_type);
168 }
169
170 module_init(hash_mac_init);
171 module_exit(hash_mac_fini);
172
