/* Called when a new connection for this protocol found. */ static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb, unsigned int dataoff) { static const u_int8_t valid_new[] = { [ICMPV6_ECHO_REQUEST - 128] = 1, [ICMPV6_NI_QUERY - 128] = 1 }; int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128; if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) { /* Can't create a new ICMPv6 `conn' with this. */ pr_debug("icmpv6: can't create new conn with type %u\n", type + 128); nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple); if (LOG_INVALID(nf_ct_net(ct), IPPROTO_ICMPV6)) nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL, "nf_ct_icmpv6: invalid new with type %d ", type + 128); return false; } return true; }
/* Returns verdict for packet, or -1 for invalid. */ static int icmpv6_packet(struct nf_conn *ct, struct sk_buff *skb, unsigned int dataoff, enum ip_conntrack_info ctinfo, const struct nf_hook_state *state) { unsigned int *timeout = nf_ct_timeout_lookup(ct); static const u8 valid_new[] = { [ICMPV6_ECHO_REQUEST - 128] = 1, [ICMPV6_NI_QUERY - 128] = 1 }; if (state->pf != NFPROTO_IPV6) return -NF_ACCEPT; if (!nf_ct_is_confirmed(ct)) { int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128; if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) { /* Can't create a new ICMPv6 `conn' with this. */ pr_debug("icmpv6: can't create new conn with type %u\n", type + 128); nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple); return -NF_ACCEPT; } } if (!timeout) timeout = icmpv6_get_timeouts(nf_ct_net(ct)); /* Do not immediately delete the connection after the first successful reply to avoid excessive conntrackd traffic and also to handle correctly ICMP echo reply duplicates. */ nf_ct_refresh_acct(ct, ctinfo, skb, *timeout); return NF_ACCEPT; }