xref: /openbmc/linux/net/netfilter/ipset/ip_set_hash_mac.c (revision cdd38c5f1ce4398ec58fec95904b75824daab7b5)
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