net/netfilter/ipset/ip_set_hash_mac.c

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