1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (C) 2014 Jozsef Kadlecsik <kadlec@netfilter.org> */
3
4 /* Kernel module implementing an IP set type: the hash:mac type */
5
6 #include <linux/jhash.h>
7 #include <linux/module.h>
8 #include <linux/etherdevice.h>
9 #include <linux/skbuff.h>
10 #include <linux/errno.h>
11 #include <linux/if_ether.h>
12 #include <net/netlink.h>
13
14 #include <linux/netfilter.h>
15 #include <linux/netfilter/ipset/ip_set.h>
16 #include <linux/netfilter/ipset/ip_set_hash.h>
17
18 #define IPSET_TYPE_REV_MIN 0
19 #define IPSET_TYPE_REV_MAX 1 /* bucketsize, initval support */
20
21 MODULE_LICENSE("GPL");
22 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
23 IP_SET_MODULE_DESC("hash:mac", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
24 MODULE_ALIAS("ip_set_hash:mac");
25
26 /* Type specific function prefix */
27 #define HTYPE hash_mac
28
29 /* Member elements */
30 struct hash_mac4_elem {
31 /* Zero valued IP addresses cannot be stored */
32 union {
33 unsigned char ether[ETH_ALEN];
34 __be32 foo[2];
35 };
36 };
37
38 /* Common functions */
39
40 static bool
hash_mac4_data_equal(const struct hash_mac4_elem * e1,const struct hash_mac4_elem * e2,u32 * multi)41 hash_mac4_data_equal(const struct hash_mac4_elem *e1,
42 const struct hash_mac4_elem *e2,
43 u32 *multi)
44 {
45 return ether_addr_equal(e1->ether, e2->ether);
46 }
47
48 static bool
hash_mac4_data_list(struct sk_buff * skb,const struct hash_mac4_elem * e)49 hash_mac4_data_list(struct sk_buff *skb, const struct hash_mac4_elem *e)
50 {
51 if (nla_put(skb, IPSET_ATTR_ETHER, ETH_ALEN, e->ether))
52 goto nla_put_failure;
53 return false;
54
55 nla_put_failure:
56 return true;
57 }
58
59 static void
hash_mac4_data_next(struct hash_mac4_elem * next,const struct hash_mac4_elem * e)60 hash_mac4_data_next(struct hash_mac4_elem *next,
61 const struct hash_mac4_elem *e)
62 {
63 }
64
65 #define MTYPE hash_mac4
66 #define HOST_MASK 32
67 #define IP_SET_EMIT_CREATE
68 #define IP_SET_PROTO_UNDEF
69 #include "ip_set_hash_gen.h"
70
71 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)72 hash_mac4_kadt(struct ip_set *set, const struct sk_buff *skb,
73 const struct xt_action_param *par,
74 enum ipset_adt adt, struct ip_set_adt_opt *opt)
75 {
76 ipset_adtfn adtfn = set->variant->adt[adt];
77 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
78 struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
79
80 if (skb_mac_header(skb) < skb->head ||
81 (skb_mac_header(skb) + ETH_HLEN) > skb->data)
82 return -EINVAL;
83
84 if (opt->flags & IPSET_DIM_ONE_SRC)
85 ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
86 else
87 ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
88
89 if (is_zero_ether_addr(e.ether))
90 return -EINVAL;
91 return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
92 }
93
94 static int
hash_mac4_uadt(struct ip_set * set,struct nlattr * tb[],enum ipset_adt adt,u32 * lineno,u32 flags,bool retried)95 hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[],
96 enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
97 {
98 ipset_adtfn adtfn = set->variant->adt[adt];
99 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
100 struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
101 int ret;
102
103 if (tb[IPSET_ATTR_LINENO])
104 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
105
106 if (unlikely(!tb[IPSET_ATTR_ETHER] ||
107 nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN))
108 return -IPSET_ERR_PROTOCOL;
109
110 ret = ip_set_get_extensions(set, tb, &ext);
111 if (ret)
112 return ret;
113 ether_addr_copy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]));
114 if (is_zero_ether_addr(e.ether))
115 return -IPSET_ERR_HASH_ELEM;
116
117 return adtfn(set, &e, &ext, &ext, flags);
118 }
119
120 static struct ip_set_type hash_mac_type __read_mostly = {
121 .name = "hash:mac",
122 .protocol = IPSET_PROTOCOL,
123 .features = IPSET_TYPE_MAC,
124 .dimension = IPSET_DIM_ONE,
125 .family = NFPROTO_UNSPEC,
126 .revision_min = IPSET_TYPE_REV_MIN,
127 .revision_max = IPSET_TYPE_REV_MAX,
128 .create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
129 .create = hash_mac_create,
130 .create_policy = {
131 [IPSET_ATTR_HASHSIZE] = { .type = NLA_U32 },
132 [IPSET_ATTR_MAXELEM] = { .type = NLA_U32 },
133 [IPSET_ATTR_INITVAL] = { .type = NLA_U32 },
134 [IPSET_ATTR_BUCKETSIZE] = { .type = NLA_U8 },
135 [IPSET_ATTR_RESIZE] = { .type = NLA_U8 },
136 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
137 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
138 },
139 .adt_policy = {
140 [IPSET_ATTR_ETHER] = { .type = NLA_BINARY,
141 .len = ETH_ALEN },
142 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
143 [IPSET_ATTR_LINENO] = { .type = NLA_U32 },
144 [IPSET_ATTR_BYTES] = { .type = NLA_U64 },
145 [IPSET_ATTR_PACKETS] = { .type = NLA_U64 },
146 [IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING,
147 .len = IPSET_MAX_COMMENT_SIZE },
148 [IPSET_ATTR_SKBMARK] = { .type = NLA_U64 },
149 [IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 },
150 [IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 },
151 },
152 .me = THIS_MODULE,
153 };
154
155 static int __init
hash_mac_init(void)156 hash_mac_init(void)
157 {
158 return ip_set_type_register(&hash_mac_type);
159 }
160
161 static void __exit
hash_mac_fini(void)162 hash_mac_fini(void)
163 {
164 rcu_barrier();
165 ip_set_type_unregister(&hash_mac_type);
166 }
167
168 module_init(hash_mac_init);
169 module_exit(hash_mac_fini);
170