net/netfilter/ipvs/ip_vs_proto.c

   1 /*
   2  * ip_vs_proto.c: transport protocol load balancing support for IPVS
   3  *
   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
  16 #define KMSG_COMPONENT "IPVS"
  17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  18
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/gfp.h>
  23 #include <linux/in.h>
  24 #include <linux/ip.h>
  25 #include <net/protocol.h>
  26 #include <net/tcp.h>
  27 #include <net/udp.h>
  28 #include <asm/system.h>
  29 #include <linux/stat.h>
  30 #include <linux/proc_fs.h>
  31
  32 #include <net/ip_vs.h>
  33
  34
  35 /*
  36  * IPVS protocols can only be registered/unregistered when the ipvs
  37  * module is loaded/unloaded, so no lock is needed in accessing the
  38  * ipvs protocol table.
  39  */
  40
  41 #define IP_VS_PROTO_TAB_SIZE            32      /* must be power of 2 */
  42 #define IP_VS_PROTO_HASH(proto)         ((proto) & (IP_VS_PROTO_TAB_SIZE-1))
  43
  44 static struct ip_vs_protocol *ip_vs_proto_table[IP_VS_PROTO_TAB_SIZE];
  45
  46
  47 /*
  48  *      register an ipvs protocol
  49  */
  50 static int __used __init register_ip_vs_protocol(struct ip_vs_protocol *pp)
  51 {
  52         unsigned hash = IP_VS_PROTO_HASH(pp->protocol);
  53
  54         pp->next = ip_vs_proto_table[hash];
  55         ip_vs_proto_table[hash] = pp;
  56
  57         if (pp->init != NULL)
  58                 pp->init(pp);
  59
  60         return 0;
  61 }
  62
  63 #if defined(CONFIG_IP_VS_PROTO_TCP) || defined(CONFIG_IP_VS_PROTO_UDP) || \
  64     defined(CONFIG_IP_VS_PROTO_SCTP) || defined(CONFIG_IP_VS_PROTO_AH) || \
  65     defined(CONFIG_IP_VS_PROTO_ESP)
  66 /*
  67  *      register an ipvs protocols netns related data
  68  */
  69 static int
  70 register_ip_vs_proto_netns(struct net *net, struct ip_vs_protocol *pp)
  71 {
  72         struct netns_ipvs *ipvs = net_ipvs(net);
  73         unsigned hash = IP_VS_PROTO_HASH(pp->protocol);
  74         struct ip_vs_proto_data *pd =
  75                         kzalloc(sizeof(struct ip_vs_proto_data), GFP_ATOMIC);
  76
  77         if (!pd) {
  78                 pr_err("%s(): no memory.\n", __func__);
  79                 return -ENOMEM;
  80         }
  81         pd->pp = pp;    /* For speed issues */
  82         pd->next = ipvs->proto_data_table[hash];
  83         ipvs->proto_data_table[hash] = pd;
  84         atomic_set(&pd->appcnt, 0);     /* Init app counter */
  85
  86         if (pp->init_netns != NULL)
  87                 pp->init_netns(net, pd);
  88
  89         return 0;
  90 }
  91 #endif
  92
  93 /*
  94  *      unregister an ipvs protocol
  95  */
  96 static int unregister_ip_vs_protocol(struct ip_vs_protocol *pp)
  97 {
  98         struct ip_vs_protocol **pp_p;
  99         unsigned hash = IP_VS_PROTO_HASH(pp->protocol);
 100
 101         pp_p = &ip_vs_proto_table[hash];
 102         for (; *pp_p; pp_p = &(*pp_p)->next) {
 103                 if (*pp_p == pp) {
 104                         *pp_p = pp->next;
 105                         if (pp->exit != NULL)
 106                                 pp->exit(pp);
 107                         return 0;
 108                 }
 109         }
 110
 111         return -ESRCH;
 112 }
 113
 114 /*
 115  *      unregister an ipvs protocols netns data
 116  */
 117 static int
 118 unregister_ip_vs_proto_netns(struct net *net, struct ip_vs_proto_data *pd)
 119 {
 120         struct netns_ipvs *ipvs = net_ipvs(net);
 121         struct ip_vs_proto_data **pd_p;
 122         unsigned hash = IP_VS_PROTO_HASH(pd->pp->protocol);
 123
 124         pd_p = &ipvs->proto_data_table[hash];
 125         for (; *pd_p; pd_p = &(*pd_p)->next) {
 126                 if (*pd_p == pd) {
 127                         *pd_p = pd->next;
 128                         if (pd->pp->exit_netns != NULL)
 129                                 pd->pp->exit_netns(net, pd);
 130                         kfree(pd);
 131                         return 0;
 132                 }
 133         }
 134
 135         return -ESRCH;
 136 }
 137
 138 /*
 139  *      get ip_vs_protocol object by its proto.
 140  */
 141 struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto)
 142 {
 143         struct ip_vs_protocol *pp;
 144         unsigned hash = IP_VS_PROTO_HASH(proto);
 145
 146         for (pp = ip_vs_proto_table[hash]; pp; pp = pp->next) {
 147                 if (pp->protocol == proto)
 148                         return pp;
 149         }
 150
 151         return NULL;
 152 }
 153 EXPORT_SYMBOL(ip_vs_proto_get);
 154
 155 /*
 156  *      get ip_vs_protocol object data by netns and proto
 157  */
 158 struct ip_vs_proto_data *
 159 __ipvs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto)
 160 {
 161         struct ip_vs_proto_data *pd;
 162         unsigned hash = IP_VS_PROTO_HASH(proto);
 163
 164         for (pd = ipvs->proto_data_table[hash]; pd; pd = pd->next) {
 165                 if (pd->pp->protocol == proto)
 166                         return pd;
 167         }
 168
 169         return NULL;
 170 }
 171
 172 struct ip_vs_proto_data *
 173 ip_vs_proto_data_get(struct net *net, unsigned short proto)
 174 {
 175         struct netns_ipvs *ipvs = net_ipvs(net);
 176
 177         return __ipvs_proto_data_get(ipvs, proto);
 178 }
 179 EXPORT_SYMBOL(ip_vs_proto_data_get);
 180
 181 /*
 182  *      Propagate event for state change to all protocols
 183  */
 184 void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags)
 185 {
 186         struct ip_vs_proto_data *pd;
 187         int i;
 188
 189         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 190                 for (pd = ipvs->proto_data_table[i]; pd; pd = pd->next) {
 191                         if (pd->pp->timeout_change)
 192                                 pd->pp->timeout_change(pd, flags);
 193                 }
 194         }
 195 }
 196
 197
 198 int *
 199 ip_vs_create_timeout_table(int *table, int size)
 200 {
 201         return kmemdup(table, size, GFP_ATOMIC);
 202 }
 203
 204
 205 /*
 206  *      Set timeout value for state specified by name
 207  */
 208 int
 209 ip_vs_set_state_timeout(int *table, int num, const char *const *names,
 210                         const char *name, int to)
 211 {
 212         int i;
 213
 214         if (!table || !name || !to)
 215                 return -EINVAL;
 216
 217         for (i = 0; i < num; i++) {
 218                 if (strcmp(names[i], name))
 219                         continue;
 220                 table[i] = to * HZ;
 221                 return 0;
 222         }
 223         return -ENOENT;
 224 }
 225
 226
 227 const char * ip_vs_state_name(__u16 proto, int state)
 228 {
 229         struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
 230
 231         if (pp == NULL || pp->state_name == NULL)
 232                 return (IPPROTO_IP == proto) ? "NONE" : "ERR!";
 233         return pp->state_name(state);
 234 }
 235
 236
 237 static void
 238 ip_vs_tcpudp_debug_packet_v4(struct ip_vs_protocol *pp,
 239                              const struct sk_buff *skb,
 240                              int offset,
 241                              const char *msg)
 242 {
 243         char buf[128];
 244         struct iphdr _iph, *ih;
 245
 246         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 247         if (ih == NULL)
 248                 sprintf(buf, "TRUNCATED");
 249         else if (ih->frag_off & htons(IP_OFFSET))
 250                 sprintf(buf, "%pI4->%pI4 frag", &ih->saddr, &ih->daddr);
 251         else {
 252                 __be16 _ports[2], *pptr;
 253
 254                 pptr = skb_header_pointer(skb, offset + ih->ihl*4,
 255                                           sizeof(_ports), _ports);
 256                 if (pptr == NULL)
 257                         sprintf(buf, "TRUNCATED %pI4->%pI4",
 258                                 &ih->saddr, &ih->daddr);
 259                 else
 260                         sprintf(buf, "%pI4:%u->%pI4:%u",
 261                                 &ih->saddr, ntohs(pptr[0]),
 262                                 &ih->daddr, ntohs(pptr[1]));
 263         }
 264
 265         pr_debug("%s: %s %s\n", msg, pp->name, buf);
 266 }
 267
 268 #ifdef CONFIG_IP_VS_IPV6
 269 static void
 270 ip_vs_tcpudp_debug_packet_v6(struct ip_vs_protocol *pp,
 271                              const struct sk_buff *skb,
 272                              int offset,
 273                              const char *msg)
 274 {
 275         char buf[192];
 276         struct ipv6hdr _iph, *ih;
 277
 278         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 279         if (ih == NULL)
 280                 sprintf(buf, "TRUNCATED");
 281         else if (ih->nexthdr == IPPROTO_FRAGMENT)
 282                 sprintf(buf, "%pI6->%pI6 frag", &ih->saddr, &ih->daddr);
 283         else {
 284                 __be16 _ports[2], *pptr;
 285
 286                 pptr = skb_header_pointer(skb, offset + sizeof(struct ipv6hdr),
 287                                           sizeof(_ports), _ports);
 288                 if (pptr == NULL)
 289                         sprintf(buf, "TRUNCATED %pI6->%pI6",
 290                                 &ih->saddr, &ih->daddr);
 291                 else
 292                         sprintf(buf, "%pI6:%u->%pI6:%u",
 293                                 &ih->saddr, ntohs(pptr[0]),
 294                                 &ih->daddr, ntohs(pptr[1]));
 295         }
 296
 297         pr_debug("%s: %s %s\n", msg, pp->name, buf);
 298 }
 299 #endif
 300
 301
 302 void
 303 ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
 304                           const struct sk_buff *skb,
 305                           int offset,
 306                           const char *msg)
 307 {
 308 #ifdef CONFIG_IP_VS_IPV6
 309         if (af == AF_INET6)
 310                 ip_vs_tcpudp_debug_packet_v6(pp, skb, offset, msg);
 311         else
 312 #endif
 313                 ip_vs_tcpudp_debug_packet_v4(pp, skb, offset, msg);
 314 }
 315
 316 /*
 317  * per network name-space init
 318  */
 319 int __net_init __ip_vs_protocol_init(struct net *net)
 320 {
 321 #ifdef CONFIG_IP_VS_PROTO_TCP
 322         register_ip_vs_proto_netns(net, &ip_vs_protocol_tcp);
 323 #endif
 324 #ifdef CONFIG_IP_VS_PROTO_UDP
 325         register_ip_vs_proto_netns(net, &ip_vs_protocol_udp);
 326 #endif
 327 #ifdef CONFIG_IP_VS_PROTO_SCTP
 328         register_ip_vs_proto_netns(net, &ip_vs_protocol_sctp);
 329 #endif
 330 #ifdef CONFIG_IP_VS_PROTO_AH
 331         register_ip_vs_proto_netns(net, &ip_vs_protocol_ah);
 332 #endif
 333 #ifdef CONFIG_IP_VS_PROTO_ESP
 334         register_ip_vs_proto_netns(net, &ip_vs_protocol_esp);
 335 #endif
 336         return 0;
 337 }
 338
 339 void __net_exit __ip_vs_protocol_cleanup(struct net *net)
 340 {
 341         struct netns_ipvs *ipvs = net_ipvs(net);
 342         struct ip_vs_proto_data *pd;
 343         int i;
 344
 345         /* unregister all the ipvs proto data for this netns */
 346         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 347                 while ((pd = ipvs->proto_data_table[i]) != NULL)
 348                         unregister_ip_vs_proto_netns(net, pd);
 349         }
 350 }
 351
 352 int __init ip_vs_protocol_init(void)
 353 {
 354         char protocols[64];
 355 #define REGISTER_PROTOCOL(p)                    \
 356         do {                                    \
 357                 register_ip_vs_protocol(p);     \
 358                 strcat(protocols, ", ");        \
 359                 strcat(protocols, (p)->name);   \
 360         } while (0)
 361
 362         protocols[0] = '\0';
 363         protocols[2] = '\0';
 364 #ifdef CONFIG_IP_VS_PROTO_TCP
 365         REGISTER_PROTOCOL(&ip_vs_protocol_tcp);
 366 #endif
 367 #ifdef CONFIG_IP_VS_PROTO_UDP
 368         REGISTER_PROTOCOL(&ip_vs_protocol_udp);
 369 #endif
 370 #ifdef CONFIG_IP_VS_PROTO_SCTP
 371         REGISTER_PROTOCOL(&ip_vs_protocol_sctp);
 372 #endif
 373 #ifdef CONFIG_IP_VS_PROTO_AH
 374         REGISTER_PROTOCOL(&ip_vs_protocol_ah);
 375 #endif
 376 #ifdef CONFIG_IP_VS_PROTO_ESP
 377         REGISTER_PROTOCOL(&ip_vs_protocol_esp);
 378 #endif
 379         pr_info("Registered protocols (%s)\n", &protocols[2]);
 380
 381         return 0;
 382 }
 383
 384
 385 void ip_vs_protocol_cleanup(void)
 386 {
 387         struct ip_vs_protocol *pp;
 388         int i;
 389
 390         /* unregister all the ipvs protocols */
 391         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 392                 while ((pp = ip_vs_proto_table[i]) != NULL)
 393                         unregister_ip_vs_protocol(pp);
 394         }
 395 }