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 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 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 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 /* Zero valued element is not supported */ 76 static const unsigned char invalid_ether[ETH_ALEN] = { 0 }; 77 78 static int 79 hash_mac4_kadt(struct ip_set *set, const struct sk_buff *skb, 80 const struct xt_action_param *par, 81 enum ipset_adt adt, struct ip_set_adt_opt *opt) 82 { 83 ipset_adtfn adtfn = set->variant->adt[adt]; 84 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } }; 85 struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set); 86 87 /* MAC can be src only */ 88 if (!(opt->flags & IPSET_DIM_ONE_SRC)) 89 return 0; 90 91 if (skb_mac_header(skb) < skb->head || 92 (skb_mac_header(skb) + ETH_HLEN) > skb->data) 93 return -EINVAL; 94 95 memcpy(e.ether, eth_hdr(skb)->h_source, ETH_ALEN); 96 if (memcmp(e.ether, invalid_ether, ETH_ALEN) == 0) 97 return -EINVAL; 98 return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags); 99 } 100 101 static int 102 hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[], 103 enum ipset_adt adt, u32 *lineno, u32 flags, bool retried) 104 { 105 ipset_adtfn adtfn = set->variant->adt[adt]; 106 struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } }; 107 struct ip_set_ext ext = IP_SET_INIT_UEXT(set); 108 int ret; 109 110 if (tb[IPSET_ATTR_LINENO]) 111 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]); 112 113 if (unlikely(!tb[IPSET_ATTR_ETHER])) 114 return -IPSET_ERR_PROTOCOL; 115 116 ret = ip_set_get_extensions(set, tb, &ext); 117 if (ret) 118 return ret; 119 memcpy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]), ETH_ALEN); 120 if (memcmp(e.ether, invalid_ether, ETH_ALEN) == 0) 121 return -IPSET_ERR_HASH_ELEM; 122 123 return adtfn(set, &e, &ext, &ext, flags); 124 } 125 126 static struct ip_set_type hash_mac_type __read_mostly = { 127 .name = "hash:mac", 128 .protocol = IPSET_PROTOCOL, 129 .features = IPSET_TYPE_MAC, 130 .dimension = IPSET_DIM_ONE, 131 .family = NFPROTO_UNSPEC, 132 .revision_min = IPSET_TYPE_REV_MIN, 133 .revision_max = IPSET_TYPE_REV_MAX, 134 .create = hash_mac_create, 135 .create_policy = { 136 [IPSET_ATTR_HASHSIZE] = { .type = NLA_U32 }, 137 [IPSET_ATTR_MAXELEM] = { .type = NLA_U32 }, 138 [IPSET_ATTR_PROBES] = { .type = NLA_U8 }, 139 [IPSET_ATTR_RESIZE] = { .type = NLA_U8 }, 140 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 }, 141 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 }, 142 }, 143 .adt_policy = { 144 [IPSET_ATTR_ETHER] = { .type = NLA_BINARY, 145 .len = ETH_ALEN }, 146 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 }, 147 [IPSET_ATTR_LINENO] = { .type = NLA_U32 }, 148 [IPSET_ATTR_BYTES] = { .type = NLA_U64 }, 149 [IPSET_ATTR_PACKETS] = { .type = NLA_U64 }, 150 [IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING, 151 .len = IPSET_MAX_COMMENT_SIZE }, 152 [IPSET_ATTR_SKBMARK] = { .type = NLA_U64 }, 153 [IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 }, 154 [IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 }, 155 }, 156 .me = THIS_MODULE, 157 }; 158 159 static int __init 160 hash_mac_init(void) 161 { 162 return ip_set_type_register(&hash_mac_type); 163 } 164 165 static void __exit 166 hash_mac_fini(void) 167 { 168 ip_set_type_unregister(&hash_mac_type); 169 } 170 171 module_init(hash_mac_init); 172 module_exit(hash_mac_fini); 173