1 #include <linux/errno.h> 2 #include <linux/ip.h> 3 #include <linux/kernel.h> 4 #include <linux/module.h> 5 #include <linux/skbuff.h> 6 #include <linux/socket.h> 7 #include <linux/types.h> 8 #include <net/checksum.h> 9 #include <net/ip.h> 10 #include <net/ip6_fib.h> 11 #include <net/lwtunnel.h> 12 #include <net/protocol.h> 13 #include <uapi/linux/ila.h> 14 #include "ila.h" 15 16 static inline struct ila_params *ila_params_lwtunnel( 17 struct lwtunnel_state *lwstate) 18 { 19 return (struct ila_params *)lwstate->data; 20 } 21 22 static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb) 23 { 24 struct dst_entry *dst = skb_dst(skb); 25 26 if (skb->protocol != htons(ETH_P_IPV6)) 27 goto drop; 28 29 ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate)); 30 31 return dst->lwtstate->orig_output(net, sk, skb); 32 33 drop: 34 kfree_skb(skb); 35 return -EINVAL; 36 } 37 38 static int ila_input(struct sk_buff *skb) 39 { 40 struct dst_entry *dst = skb_dst(skb); 41 42 if (skb->protocol != htons(ETH_P_IPV6)) 43 goto drop; 44 45 ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate)); 46 47 return dst->lwtstate->orig_input(skb); 48 49 drop: 50 kfree_skb(skb); 51 return -EINVAL; 52 } 53 54 static struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = { 55 [ILA_ATTR_LOCATOR] = { .type = NLA_U64, }, 56 [ILA_ATTR_CSUM_MODE] = { .type = NLA_U8, }, 57 }; 58 59 static int ila_build_state(struct net_device *dev, struct nlattr *nla, 60 unsigned int family, const void *cfg, 61 struct lwtunnel_state **ts) 62 { 63 struct ila_params *p; 64 struct nlattr *tb[ILA_ATTR_MAX + 1]; 65 size_t encap_len = sizeof(*p); 66 struct lwtunnel_state *newts; 67 const struct fib6_config *cfg6 = cfg; 68 struct ila_addr *iaddr; 69 int ret; 70 71 if (family != AF_INET6) 72 return -EINVAL; 73 74 if (cfg6->fc_dst_len < sizeof(struct ila_locator) + 1) { 75 /* Need to have full locator and at least type field 76 * included in destination 77 */ 78 return -EINVAL; 79 } 80 81 iaddr = (struct ila_addr *)&cfg6->fc_dst; 82 83 if (!ila_addr_is_ila(iaddr) || ila_csum_neutral_set(iaddr->ident)) { 84 /* Don't allow translation for a non-ILA address or checksum 85 * neutral flag to be set. 86 */ 87 return -EINVAL; 88 } 89 90 ret = nla_parse_nested(tb, ILA_ATTR_MAX, nla, 91 ila_nl_policy); 92 if (ret < 0) 93 return ret; 94 95 if (!tb[ILA_ATTR_LOCATOR]) 96 return -EINVAL; 97 98 newts = lwtunnel_state_alloc(encap_len); 99 if (!newts) 100 return -ENOMEM; 101 102 newts->len = encap_len; 103 p = ila_params_lwtunnel(newts); 104 105 p->locator.v64 = (__force __be64)nla_get_u64(tb[ILA_ATTR_LOCATOR]); 106 107 /* Precompute checksum difference for translation since we 108 * know both the old locator and the new one. 109 */ 110 p->locator_match = iaddr->loc; 111 p->csum_diff = compute_csum_diff8( 112 (__be32 *)&p->locator_match, (__be32 *)&p->locator); 113 114 if (tb[ILA_ATTR_CSUM_MODE]) 115 p->csum_mode = nla_get_u8(tb[ILA_ATTR_CSUM_MODE]); 116 117 ila_init_saved_csum(p); 118 119 newts->type = LWTUNNEL_ENCAP_ILA; 120 newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT | 121 LWTUNNEL_STATE_INPUT_REDIRECT; 122 123 *ts = newts; 124 125 return 0; 126 } 127 128 static int ila_fill_encap_info(struct sk_buff *skb, 129 struct lwtunnel_state *lwtstate) 130 { 131 struct ila_params *p = ila_params_lwtunnel(lwtstate); 132 133 if (nla_put_u64_64bit(skb, ILA_ATTR_LOCATOR, (__force u64)p->locator.v64, 134 ILA_ATTR_PAD)) 135 goto nla_put_failure; 136 if (nla_put_u8(skb, ILA_ATTR_CSUM_MODE, (__force u8)p->csum_mode)) 137 goto nla_put_failure; 138 139 return 0; 140 141 nla_put_failure: 142 return -EMSGSIZE; 143 } 144 145 static int ila_encap_nlsize(struct lwtunnel_state *lwtstate) 146 { 147 return nla_total_size_64bit(sizeof(u64)) + /* ILA_ATTR_LOCATOR */ 148 nla_total_size(sizeof(u8)) + /* ILA_ATTR_CSUM_MODE */ 149 0; 150 } 151 152 static int ila_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b) 153 { 154 struct ila_params *a_p = ila_params_lwtunnel(a); 155 struct ila_params *b_p = ila_params_lwtunnel(b); 156 157 return (a_p->locator.v64 != b_p->locator.v64); 158 } 159 160 static const struct lwtunnel_encap_ops ila_encap_ops = { 161 .build_state = ila_build_state, 162 .output = ila_output, 163 .input = ila_input, 164 .fill_encap = ila_fill_encap_info, 165 .get_encap_size = ila_encap_nlsize, 166 .cmp_encap = ila_encap_cmp, 167 }; 168 169 int ila_lwt_init(void) 170 { 171 return lwtunnel_encap_add_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA); 172 } 173 174 void ila_lwt_fini(void) 175 { 176 lwtunnel_encap_del_ops(&ila_encap_ops, LWTUNNEL_ENCAP_ILA); 177 } 178