Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * ip_vs_proto_icmp.c: ICMP load balancing support for IP Virtual Server |
| 3 | * |
| 4 | * Authors: Julian Anastasov <ja@ssi.bg>, March 2002 |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * version 2 as published by the Free Software Foundation; |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/icmp.h> |
| 15 | #include <linux/netfilter.h> |
| 16 | #include <linux/netfilter_ipv4.h> |
| 17 | |
| 18 | #include <net/ip_vs.h> |
| 19 | |
| 20 | |
| 21 | static int icmp_timeouts[1] = { 1*60*HZ }; |
| 22 | |
| 23 | static char * icmp_state_name_table[1] = { "ICMP" }; |
| 24 | |
| 25 | static struct ip_vs_conn * |
| 26 | icmp_conn_in_get(const struct sk_buff *skb, |
| 27 | struct ip_vs_protocol *pp, |
| 28 | const struct iphdr *iph, |
| 29 | unsigned int proto_off, |
| 30 | int inverse) |
| 31 | { |
| 32 | #if 0 |
| 33 | struct ip_vs_conn *cp; |
| 34 | |
| 35 | if (likely(!inverse)) { |
| 36 | cp = ip_vs_conn_in_get(iph->protocol, |
| 37 | iph->saddr, 0, |
| 38 | iph->daddr, 0); |
| 39 | } else { |
| 40 | cp = ip_vs_conn_in_get(iph->protocol, |
| 41 | iph->daddr, 0, |
| 42 | iph->saddr, 0); |
| 43 | } |
| 44 | |
| 45 | return cp; |
| 46 | |
| 47 | #else |
| 48 | return NULL; |
| 49 | #endif |
| 50 | } |
| 51 | |
| 52 | static struct ip_vs_conn * |
| 53 | icmp_conn_out_get(const struct sk_buff *skb, |
| 54 | struct ip_vs_protocol *pp, |
| 55 | const struct iphdr *iph, |
| 56 | unsigned int proto_off, |
| 57 | int inverse) |
| 58 | { |
| 59 | #if 0 |
| 60 | struct ip_vs_conn *cp; |
| 61 | |
| 62 | if (likely(!inverse)) { |
| 63 | cp = ip_vs_conn_out_get(iph->protocol, |
| 64 | iph->saddr, 0, |
| 65 | iph->daddr, 0); |
| 66 | } else { |
| 67 | cp = ip_vs_conn_out_get(IPPROTO_UDP, |
| 68 | iph->daddr, 0, |
| 69 | iph->saddr, 0); |
| 70 | } |
| 71 | |
| 72 | return cp; |
| 73 | #else |
| 74 | return NULL; |
| 75 | #endif |
| 76 | } |
| 77 | |
| 78 | static int |
| 79 | icmp_conn_schedule(struct sk_buff *skb, struct ip_vs_protocol *pp, |
| 80 | int *verdict, struct ip_vs_conn **cpp) |
| 81 | { |
| 82 | *verdict = NF_ACCEPT; |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | static int |
| 87 | icmp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp) |
| 88 | { |
| 89 | if (!(skb->nh.iph->frag_off & __constant_htons(IP_OFFSET))) { |
| 90 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) { |
| 91 | if (ip_vs_checksum_complete(skb, skb->nh.iph->ihl * 4)) { |
| 92 | IP_VS_DBG_RL_PKT(0, pp, skb, 0, "Failed checksum for"); |
| 93 | return 0; |
| 94 | } |
| 95 | } |
| 96 | } |
| 97 | return 1; |
| 98 | } |
| 99 | |
| 100 | static void |
| 101 | icmp_debug_packet(struct ip_vs_protocol *pp, |
| 102 | const struct sk_buff *skb, |
| 103 | int offset, |
| 104 | const char *msg) |
| 105 | { |
| 106 | char buf[256]; |
| 107 | struct iphdr _iph, *ih; |
| 108 | |
| 109 | ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); |
| 110 | if (ih == NULL) |
| 111 | sprintf(buf, "%s TRUNCATED", pp->name); |
| 112 | else if (ih->frag_off & __constant_htons(IP_OFFSET)) |
| 113 | sprintf(buf, "%s %u.%u.%u.%u->%u.%u.%u.%u frag", |
| 114 | pp->name, NIPQUAD(ih->saddr), |
| 115 | NIPQUAD(ih->daddr)); |
| 116 | else { |
| 117 | struct icmphdr _icmph, *ic; |
| 118 | |
| 119 | ic = skb_header_pointer(skb, offset + ih->ihl*4, |
| 120 | sizeof(_icmph), &_icmph); |
| 121 | if (ic == NULL) |
| 122 | sprintf(buf, "%s TRUNCATED to %u bytes\n", |
| 123 | pp->name, skb->len - offset); |
| 124 | else |
| 125 | sprintf(buf, "%s %u.%u.%u.%u->%u.%u.%u.%u T:%d C:%d", |
| 126 | pp->name, NIPQUAD(ih->saddr), |
| 127 | NIPQUAD(ih->daddr), |
| 128 | ic->type, ic->code); |
| 129 | } |
| 130 | printk(KERN_DEBUG "IPVS: %s: %s\n", msg, buf); |
| 131 | } |
| 132 | |
| 133 | static int |
| 134 | icmp_state_transition(struct ip_vs_conn *cp, int direction, |
| 135 | const struct sk_buff *skb, |
| 136 | struct ip_vs_protocol *pp) |
| 137 | { |
| 138 | cp->timeout = pp->timeout_table[IP_VS_ICMP_S_NORMAL]; |
| 139 | return 1; |
| 140 | } |
| 141 | |
| 142 | static int |
| 143 | icmp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to) |
| 144 | { |
| 145 | int num; |
| 146 | char **names; |
| 147 | |
| 148 | num = IP_VS_ICMP_S_LAST; |
| 149 | names = icmp_state_name_table; |
| 150 | return ip_vs_set_state_timeout(pp->timeout_table, num, names, sname, to); |
| 151 | } |
| 152 | |
| 153 | |
| 154 | static void icmp_init(struct ip_vs_protocol *pp) |
| 155 | { |
| 156 | pp->timeout_table = icmp_timeouts; |
| 157 | } |
| 158 | |
| 159 | static void icmp_exit(struct ip_vs_protocol *pp) |
| 160 | { |
| 161 | } |
| 162 | |
| 163 | struct ip_vs_protocol ip_vs_protocol_icmp = { |
| 164 | .name = "ICMP", |
| 165 | .protocol = IPPROTO_ICMP, |
| 166 | .dont_defrag = 0, |
| 167 | .init = icmp_init, |
| 168 | .exit = icmp_exit, |
| 169 | .conn_schedule = icmp_conn_schedule, |
| 170 | .conn_in_get = icmp_conn_in_get, |
| 171 | .conn_out_get = icmp_conn_out_get, |
| 172 | .snat_handler = NULL, |
| 173 | .dnat_handler = NULL, |
| 174 | .csum_check = icmp_csum_check, |
| 175 | .state_transition = icmp_state_transition, |
| 176 | .register_app = NULL, |
| 177 | .unregister_app = NULL, |
| 178 | .app_conn_bind = NULL, |
| 179 | .debug_packet = icmp_debug_packet, |
| 180 | .timeout_change = NULL, |
| 181 | .set_state_timeout = icmp_set_state_timeout, |
| 182 | }; |