Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * ip_vs_proto_udp.c: UDP load balancing support for IPVS |
| 3 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * Authors: Wensong Zhang <wensong@linuxvirtualserver.org> |
| 5 | * Julian Anastasov <ja@ssi.bg> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * Changes: |
| 13 | * |
| 14 | */ |
| 15 | |
Hannes Eder | 9aada7a | 2009-07-30 14:29:44 -0700 | [diff] [blame] | 16 | #define KMSG_COMPONENT "IPVS" |
| 17 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 18 | |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 19 | #include <linux/in.h> |
| 20 | #include <linux/ip.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/kernel.h> |
Herbert Xu | af1e1cf | 2007-10-14 00:39:33 -0700 | [diff] [blame] | 22 | #include <linux/netfilter.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/netfilter_ipv4.h> |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 24 | #include <linux/udp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | #include <net/ip_vs.h> |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 27 | #include <net/ip.h> |
Stephen Rothwell | 63f2c04 | 2008-09-12 23:23:50 -0700 | [diff] [blame] | 28 | #include <net/ip6_checksum.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | static int |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 31 | udp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_protocol *pp, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | int *verdict, struct ip_vs_conn **cpp) |
| 33 | { |
Hans Schillstrom | fc72325 | 2011-01-03 14:44:43 +0100 | [diff] [blame^] | 34 | struct net *net; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | struct ip_vs_service *svc; |
| 36 | struct udphdr _udph, *uh; |
Julius Volz | 3c2e050 | 2008-09-02 15:55:38 +0200 | [diff] [blame] | 37 | struct ip_vs_iphdr iph; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 39 | ip_vs_fill_iphdr(af, skb_network_header(skb), &iph); |
Julius Volz | 3c2e050 | 2008-09-02 15:55:38 +0200 | [diff] [blame] | 40 | |
| 41 | uh = skb_header_pointer(skb, iph.len, sizeof(_udph), &_udph); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | if (uh == NULL) { |
| 43 | *verdict = NF_DROP; |
| 44 | return 0; |
| 45 | } |
Hans Schillstrom | fc72325 | 2011-01-03 14:44:43 +0100 | [diff] [blame^] | 46 | net = skb_net(skb); |
| 47 | svc = ip_vs_service_get(net, af, skb->mark, iph.protocol, |
Julius Volz | 3c2e050 | 2008-09-02 15:55:38 +0200 | [diff] [blame] | 48 | &iph.daddr, uh->dest); |
| 49 | if (svc) { |
Julian Anastasov | 190ecd2 | 2010-10-17 16:24:37 +0300 | [diff] [blame] | 50 | int ignored; |
| 51 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | if (ip_vs_todrop()) { |
| 53 | /* |
| 54 | * It seems that we are very loaded. |
| 55 | * We have to drop this packet :( |
| 56 | */ |
| 57 | ip_vs_service_put(svc); |
| 58 | *verdict = NF_DROP; |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | /* |
| 63 | * Let the virtual server select a real server for the |
| 64 | * incoming connection, and create a connection entry. |
| 65 | */ |
Julian Anastasov | 190ecd2 | 2010-10-17 16:24:37 +0300 | [diff] [blame] | 66 | *cpp = ip_vs_schedule(svc, skb, pp, &ignored); |
Hans Schillstrom | a5959d5 | 2010-11-19 14:25:10 +0100 | [diff] [blame] | 67 | if (!*cpp && ignored <= 0) { |
| 68 | if (!ignored) |
| 69 | *verdict = ip_vs_leave(svc, skb, pp); |
| 70 | else { |
| 71 | ip_vs_service_put(svc); |
| 72 | *verdict = NF_DROP; |
| 73 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | return 0; |
| 75 | } |
| 76 | ip_vs_service_put(svc); |
| 77 | } |
Hans Schillstrom | a5959d5 | 2010-11-19 14:25:10 +0100 | [diff] [blame] | 78 | /* NF_ACCEPT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | return 1; |
| 80 | } |
| 81 | |
| 82 | |
| 83 | static inline void |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 84 | udp_fast_csum_update(int af, struct udphdr *uhdr, |
| 85 | const union nf_inet_addr *oldip, |
| 86 | const union nf_inet_addr *newip, |
Al Viro | 014d730 | 2006-09-28 14:29:52 -0700 | [diff] [blame] | 87 | __be16 oldport, __be16 newport) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | { |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 89 | #ifdef CONFIG_IP_VS_IPV6 |
| 90 | if (af == AF_INET6) |
| 91 | uhdr->check = |
| 92 | csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6, |
| 93 | ip_vs_check_diff2(oldport, newport, |
| 94 | ~csum_unfold(uhdr->check)))); |
| 95 | else |
| 96 | #endif |
| 97 | uhdr->check = |
| 98 | csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip, |
| 99 | ip_vs_check_diff2(oldport, newport, |
| 100 | ~csum_unfold(uhdr->check)))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | if (!uhdr->check) |
Al Viro | f6ab028 | 2006-11-16 02:36:50 -0800 | [diff] [blame] | 102 | uhdr->check = CSUM_MANGLED_0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | } |
| 104 | |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 105 | static inline void |
| 106 | udp_partial_csum_update(int af, struct udphdr *uhdr, |
| 107 | const union nf_inet_addr *oldip, |
| 108 | const union nf_inet_addr *newip, |
| 109 | __be16 oldlen, __be16 newlen) |
| 110 | { |
| 111 | #ifdef CONFIG_IP_VS_IPV6 |
| 112 | if (af == AF_INET6) |
| 113 | uhdr->check = |
Julian Anastasov | 5bc9068 | 2010-10-17 16:14:31 +0300 | [diff] [blame] | 114 | ~csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6, |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 115 | ip_vs_check_diff2(oldlen, newlen, |
Julian Anastasov | 5bc9068 | 2010-10-17 16:14:31 +0300 | [diff] [blame] | 116 | csum_unfold(uhdr->check)))); |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 117 | else |
| 118 | #endif |
| 119 | uhdr->check = |
Julian Anastasov | 5bc9068 | 2010-10-17 16:14:31 +0300 | [diff] [blame] | 120 | ~csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip, |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 121 | ip_vs_check_diff2(oldlen, newlen, |
Julian Anastasov | 5bc9068 | 2010-10-17 16:14:31 +0300 | [diff] [blame] | 122 | csum_unfold(uhdr->check)))); |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 123 | } |
| 124 | |
| 125 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | static int |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 127 | udp_snat_handler(struct sk_buff *skb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | struct ip_vs_protocol *pp, struct ip_vs_conn *cp) |
| 129 | { |
| 130 | struct udphdr *udph; |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 131 | unsigned int udphoff; |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 132 | int oldlen; |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 133 | int payload_csum = 0; |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 134 | |
| 135 | #ifdef CONFIG_IP_VS_IPV6 |
| 136 | if (cp->af == AF_INET6) |
| 137 | udphoff = sizeof(struct ipv6hdr); |
| 138 | else |
| 139 | #endif |
| 140 | udphoff = ip_hdrlen(skb); |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 141 | oldlen = skb->len - udphoff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
| 143 | /* csum_check requires unshared skb */ |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 144 | if (!skb_make_writable(skb, udphoff+sizeof(*udph))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | return 0; |
| 146 | |
| 147 | if (unlikely(cp->app != NULL)) { |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 148 | int ret; |
| 149 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | /* Some checks before mangling */ |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 151 | if (pp->csum_check && !pp->csum_check(cp->af, skb, pp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | return 0; |
| 153 | |
| 154 | /* |
| 155 | * Call application helper if needed |
| 156 | */ |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 157 | if (!(ret = ip_vs_app_pkt_out(cp, skb))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | return 0; |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 159 | /* ret=2: csum update is needed after payload mangling */ |
| 160 | if (ret == 1) |
| 161 | oldlen = skb->len - udphoff; |
| 162 | else |
| 163 | payload_csum = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | } |
| 165 | |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 166 | udph = (void *)skb_network_header(skb) + udphoff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | udph->source = cp->vport; |
| 168 | |
| 169 | /* |
| 170 | * Adjust UDP checksums |
| 171 | */ |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 172 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
| 173 | udp_partial_csum_update(cp->af, udph, &cp->daddr, &cp->vaddr, |
Harvey Harrison | ca62059 | 2008-11-06 23:09:56 -0800 | [diff] [blame] | 174 | htons(oldlen), |
| 175 | htons(skb->len - udphoff)); |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 176 | } else if (!payload_csum && (udph->check != 0)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | /* Only port and addr are changed, do fast csum update */ |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 178 | udp_fast_csum_update(cp->af, udph, &cp->daddr, &cp->vaddr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | cp->dport, cp->vport); |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 180 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 181 | skb->ip_summed = (cp->app && pp->csum_check) ? |
| 182 | CHECKSUM_UNNECESSARY : CHECKSUM_NONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | } else { |
| 184 | /* full checksum calculation */ |
| 185 | udph->check = 0; |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 186 | skb->csum = skb_checksum(skb, udphoff, skb->len - udphoff, 0); |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 187 | #ifdef CONFIG_IP_VS_IPV6 |
| 188 | if (cp->af == AF_INET6) |
| 189 | udph->check = csum_ipv6_magic(&cp->vaddr.in6, |
| 190 | &cp->caddr.in6, |
| 191 | skb->len - udphoff, |
| 192 | cp->protocol, skb->csum); |
| 193 | else |
| 194 | #endif |
| 195 | udph->check = csum_tcpudp_magic(cp->vaddr.ip, |
| 196 | cp->caddr.ip, |
| 197 | skb->len - udphoff, |
| 198 | cp->protocol, |
| 199 | skb->csum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | if (udph->check == 0) |
Al Viro | f6ab028 | 2006-11-16 02:36:50 -0800 | [diff] [blame] | 201 | udph->check = CSUM_MANGLED_0; |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 202 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n", |
| 204 | pp->name, udph->check, |
| 205 | (char*)&(udph->check) - (char*)udph); |
| 206 | } |
| 207 | return 1; |
| 208 | } |
| 209 | |
| 210 | |
| 211 | static int |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 212 | udp_dnat_handler(struct sk_buff *skb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | struct ip_vs_protocol *pp, struct ip_vs_conn *cp) |
| 214 | { |
| 215 | struct udphdr *udph; |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 216 | unsigned int udphoff; |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 217 | int oldlen; |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 218 | int payload_csum = 0; |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 219 | |
| 220 | #ifdef CONFIG_IP_VS_IPV6 |
| 221 | if (cp->af == AF_INET6) |
| 222 | udphoff = sizeof(struct ipv6hdr); |
| 223 | else |
| 224 | #endif |
| 225 | udphoff = ip_hdrlen(skb); |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 226 | oldlen = skb->len - udphoff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | |
| 228 | /* csum_check requires unshared skb */ |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 229 | if (!skb_make_writable(skb, udphoff+sizeof(*udph))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | return 0; |
| 231 | |
| 232 | if (unlikely(cp->app != NULL)) { |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 233 | int ret; |
| 234 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | /* Some checks before mangling */ |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 236 | if (pp->csum_check && !pp->csum_check(cp->af, skb, pp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | return 0; |
| 238 | |
| 239 | /* |
| 240 | * Attempt ip_vs_app call. |
| 241 | * It will fix ip_vs_conn |
| 242 | */ |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 243 | if (!(ret = ip_vs_app_pkt_in(cp, skb))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | return 0; |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 245 | /* ret=2: csum update is needed after payload mangling */ |
| 246 | if (ret == 1) |
| 247 | oldlen = skb->len - udphoff; |
| 248 | else |
| 249 | payload_csum = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | } |
| 251 | |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 252 | udph = (void *)skb_network_header(skb) + udphoff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | udph->dest = cp->dport; |
| 254 | |
| 255 | /* |
| 256 | * Adjust UDP checksums |
| 257 | */ |
Simon Horman | 503e81f | 2008-09-08 12:04:21 +1000 | [diff] [blame] | 258 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
Julian Anastasov | 5bc9068 | 2010-10-17 16:14:31 +0300 | [diff] [blame] | 259 | udp_partial_csum_update(cp->af, udph, &cp->vaddr, &cp->daddr, |
Harvey Harrison | ca62059 | 2008-11-06 23:09:56 -0800 | [diff] [blame] | 260 | htons(oldlen), |
| 261 | htons(skb->len - udphoff)); |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 262 | } else if (!payload_csum && (udph->check != 0)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | /* Only port and addr are changed, do fast csum update */ |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 264 | udp_fast_csum_update(cp->af, udph, &cp->vaddr, &cp->daddr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | cp->vport, cp->dport); |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 266 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
Julian Anastasov | 8b27b10 | 2010-10-17 16:17:20 +0300 | [diff] [blame] | 267 | skb->ip_summed = (cp->app && pp->csum_check) ? |
| 268 | CHECKSUM_UNNECESSARY : CHECKSUM_NONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | } else { |
| 270 | /* full checksum calculation */ |
| 271 | udph->check = 0; |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 272 | skb->csum = skb_checksum(skb, udphoff, skb->len - udphoff, 0); |
Julius Volz | 0bbdd42 | 2008-09-02 15:55:42 +0200 | [diff] [blame] | 273 | #ifdef CONFIG_IP_VS_IPV6 |
| 274 | if (cp->af == AF_INET6) |
| 275 | udph->check = csum_ipv6_magic(&cp->caddr.in6, |
| 276 | &cp->daddr.in6, |
| 277 | skb->len - udphoff, |
| 278 | cp->protocol, skb->csum); |
| 279 | else |
| 280 | #endif |
| 281 | udph->check = csum_tcpudp_magic(cp->caddr.ip, |
| 282 | cp->daddr.ip, |
| 283 | skb->len - udphoff, |
| 284 | cp->protocol, |
| 285 | skb->csum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | if (udph->check == 0) |
Al Viro | f6ab028 | 2006-11-16 02:36:50 -0800 | [diff] [blame] | 287 | udph->check = CSUM_MANGLED_0; |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 288 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | } |
| 290 | return 1; |
| 291 | } |
| 292 | |
| 293 | |
| 294 | static int |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 295 | udp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | { |
| 297 | struct udphdr _udph, *uh; |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 298 | unsigned int udphoff; |
| 299 | |
| 300 | #ifdef CONFIG_IP_VS_IPV6 |
| 301 | if (af == AF_INET6) |
| 302 | udphoff = sizeof(struct ipv6hdr); |
| 303 | else |
| 304 | #endif |
| 305 | udphoff = ip_hdrlen(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | |
| 307 | uh = skb_header_pointer(skb, udphoff, sizeof(_udph), &_udph); |
| 308 | if (uh == NULL) |
| 309 | return 0; |
| 310 | |
| 311 | if (uh->check != 0) { |
| 312 | switch (skb->ip_summed) { |
| 313 | case CHECKSUM_NONE: |
| 314 | skb->csum = skb_checksum(skb, udphoff, |
| 315 | skb->len - udphoff, 0); |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 316 | case CHECKSUM_COMPLETE: |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 317 | #ifdef CONFIG_IP_VS_IPV6 |
| 318 | if (af == AF_INET6) { |
| 319 | if (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, |
| 320 | &ipv6_hdr(skb)->daddr, |
| 321 | skb->len - udphoff, |
| 322 | ipv6_hdr(skb)->nexthdr, |
| 323 | skb->csum)) { |
Julian Anastasov | 0d79641 | 2010-10-17 16:46:17 +0300 | [diff] [blame] | 324 | IP_VS_DBG_RL_PKT(0, af, pp, skb, 0, |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 325 | "Failed checksum for"); |
| 326 | return 0; |
| 327 | } |
| 328 | } else |
| 329 | #endif |
| 330 | if (csum_tcpudp_magic(ip_hdr(skb)->saddr, |
| 331 | ip_hdr(skb)->daddr, |
| 332 | skb->len - udphoff, |
| 333 | ip_hdr(skb)->protocol, |
| 334 | skb->csum)) { |
Julian Anastasov | 0d79641 | 2010-10-17 16:46:17 +0300 | [diff] [blame] | 335 | IP_VS_DBG_RL_PKT(0, af, pp, skb, 0, |
Julius Volz | 51ef348 | 2008-09-02 15:55:40 +0200 | [diff] [blame] | 336 | "Failed checksum for"); |
| 337 | return 0; |
| 338 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | break; |
| 340 | default: |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 341 | /* No need to checksum. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | break; |
| 343 | } |
| 344 | } |
| 345 | return 1; |
| 346 | } |
| 347 | |
| 348 | |
| 349 | /* |
| 350 | * Note: the caller guarantees that only one of register_app, |
| 351 | * unregister_app or app_conn_bind is called each time. |
| 352 | */ |
| 353 | |
| 354 | #define UDP_APP_TAB_BITS 4 |
| 355 | #define UDP_APP_TAB_SIZE (1 << UDP_APP_TAB_BITS) |
| 356 | #define UDP_APP_TAB_MASK (UDP_APP_TAB_SIZE - 1) |
| 357 | |
| 358 | static struct list_head udp_apps[UDP_APP_TAB_SIZE]; |
| 359 | static DEFINE_SPINLOCK(udp_app_lock); |
| 360 | |
Al Viro | 75e7ce6 | 2006-11-14 21:13:28 -0800 | [diff] [blame] | 361 | static inline __u16 udp_app_hashkey(__be16 port) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | { |
Al Viro | 75e7ce6 | 2006-11-14 21:13:28 -0800 | [diff] [blame] | 363 | return (((__force u16)port >> UDP_APP_TAB_BITS) ^ (__force u16)port) |
| 364 | & UDP_APP_TAB_MASK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | } |
| 366 | |
| 367 | |
| 368 | static int udp_register_app(struct ip_vs_app *inc) |
| 369 | { |
| 370 | struct ip_vs_app *i; |
Al Viro | 75e7ce6 | 2006-11-14 21:13:28 -0800 | [diff] [blame] | 371 | __u16 hash; |
| 372 | __be16 port = inc->port; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | int ret = 0; |
| 374 | |
| 375 | hash = udp_app_hashkey(port); |
| 376 | |
| 377 | |
| 378 | spin_lock_bh(&udp_app_lock); |
| 379 | list_for_each_entry(i, &udp_apps[hash], p_list) { |
| 380 | if (i->port == port) { |
| 381 | ret = -EEXIST; |
| 382 | goto out; |
| 383 | } |
| 384 | } |
| 385 | list_add(&inc->p_list, &udp_apps[hash]); |
| 386 | atomic_inc(&ip_vs_protocol_udp.appcnt); |
| 387 | |
| 388 | out: |
| 389 | spin_unlock_bh(&udp_app_lock); |
| 390 | return ret; |
| 391 | } |
| 392 | |
| 393 | |
| 394 | static void |
| 395 | udp_unregister_app(struct ip_vs_app *inc) |
| 396 | { |
| 397 | spin_lock_bh(&udp_app_lock); |
| 398 | atomic_dec(&ip_vs_protocol_udp.appcnt); |
| 399 | list_del(&inc->p_list); |
| 400 | spin_unlock_bh(&udp_app_lock); |
| 401 | } |
| 402 | |
| 403 | |
| 404 | static int udp_app_conn_bind(struct ip_vs_conn *cp) |
| 405 | { |
| 406 | int hash; |
| 407 | struct ip_vs_app *inc; |
| 408 | int result = 0; |
| 409 | |
| 410 | /* Default binding: bind app only for NAT */ |
| 411 | if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) |
| 412 | return 0; |
| 413 | |
| 414 | /* Lookup application incarnations and bind the right one */ |
| 415 | hash = udp_app_hashkey(cp->vport); |
| 416 | |
| 417 | spin_lock(&udp_app_lock); |
| 418 | list_for_each_entry(inc, &udp_apps[hash], p_list) { |
| 419 | if (inc->port == cp->vport) { |
| 420 | if (unlikely(!ip_vs_app_inc_get(inc))) |
| 421 | break; |
| 422 | spin_unlock(&udp_app_lock); |
| 423 | |
Hannes Eder | 1e3e238 | 2009-08-02 11:05:41 +0000 | [diff] [blame] | 424 | IP_VS_DBG_BUF(9, "%s(): Binding conn %s:%u->" |
Julius Volz | cfc78c5 | 2008-09-02 15:55:53 +0200 | [diff] [blame] | 425 | "%s:%u to app %s on port %u\n", |
| 426 | __func__, |
| 427 | IP_VS_DBG_ADDR(cp->af, &cp->caddr), |
| 428 | ntohs(cp->cport), |
| 429 | IP_VS_DBG_ADDR(cp->af, &cp->vaddr), |
| 430 | ntohs(cp->vport), |
| 431 | inc->name, ntohs(inc->port)); |
| 432 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | cp->app = inc; |
| 434 | if (inc->init_conn) |
| 435 | result = inc->init_conn(inc, cp); |
| 436 | goto out; |
| 437 | } |
| 438 | } |
| 439 | spin_unlock(&udp_app_lock); |
| 440 | |
| 441 | out: |
| 442 | return result; |
| 443 | } |
| 444 | |
| 445 | |
| 446 | static int udp_timeouts[IP_VS_UDP_S_LAST+1] = { |
| 447 | [IP_VS_UDP_S_NORMAL] = 5*60*HZ, |
| 448 | [IP_VS_UDP_S_LAST] = 2*HZ, |
| 449 | }; |
| 450 | |
Jan Engelhardt | 36cbd3d | 2009-08-05 10:42:58 -0700 | [diff] [blame] | 451 | static const char *const udp_state_name_table[IP_VS_UDP_S_LAST+1] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | [IP_VS_UDP_S_NORMAL] = "UDP", |
| 453 | [IP_VS_UDP_S_LAST] = "BUG!", |
| 454 | }; |
| 455 | |
| 456 | |
| 457 | static int |
| 458 | udp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to) |
| 459 | { |
| 460 | return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_UDP_S_LAST, |
| 461 | udp_state_name_table, sname, to); |
| 462 | } |
| 463 | |
| 464 | static const char * udp_state_name(int state) |
| 465 | { |
| 466 | if (state >= IP_VS_UDP_S_LAST) |
| 467 | return "ERR!"; |
| 468 | return udp_state_name_table[state] ? udp_state_name_table[state] : "?"; |
| 469 | } |
| 470 | |
| 471 | static int |
| 472 | udp_state_transition(struct ip_vs_conn *cp, int direction, |
| 473 | const struct sk_buff *skb, |
| 474 | struct ip_vs_protocol *pp) |
| 475 | { |
| 476 | cp->timeout = pp->timeout_table[IP_VS_UDP_S_NORMAL]; |
| 477 | return 1; |
| 478 | } |
| 479 | |
| 480 | static void udp_init(struct ip_vs_protocol *pp) |
| 481 | { |
| 482 | IP_VS_INIT_HASH_TABLE(udp_apps); |
| 483 | pp->timeout_table = udp_timeouts; |
| 484 | } |
| 485 | |
| 486 | static void udp_exit(struct ip_vs_protocol *pp) |
| 487 | { |
| 488 | } |
| 489 | |
| 490 | |
| 491 | struct ip_vs_protocol ip_vs_protocol_udp = { |
| 492 | .name = "UDP", |
| 493 | .protocol = IPPROTO_UDP, |
Julian Anastasov | 2ad17de | 2008-04-29 03:21:23 -0700 | [diff] [blame] | 494 | .num_states = IP_VS_UDP_S_LAST, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | .dont_defrag = 0, |
| 496 | .init = udp_init, |
| 497 | .exit = udp_exit, |
| 498 | .conn_schedule = udp_conn_schedule, |
Simon Horman | 5c0d237 | 2010-08-02 17:12:44 +0200 | [diff] [blame] | 499 | .conn_in_get = ip_vs_conn_in_get_proto, |
| 500 | .conn_out_get = ip_vs_conn_out_get_proto, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | .snat_handler = udp_snat_handler, |
| 502 | .dnat_handler = udp_dnat_handler, |
| 503 | .csum_check = udp_csum_check, |
| 504 | .state_transition = udp_state_transition, |
| 505 | .state_name = udp_state_name, |
| 506 | .register_app = udp_register_app, |
| 507 | .unregister_app = udp_unregister_app, |
| 508 | .app_conn_bind = udp_app_conn_bind, |
| 509 | .debug_packet = ip_vs_tcpudp_debug_packet, |
| 510 | .timeout_change = NULL, |
| 511 | .set_state_timeout = udp_set_state_timeout, |
| 512 | }; |