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 <linux/stat.h>
  29 #include <linux/proc_fs.h>
  30
  31 #include <net/ip_vs.h>
  32
  33
  34 /*
  35  * IPVS protocols can only be registered/unregistered when the ipvs
  36  * module is loaded/unloaded, so no lock is needed in accessing the
  37  * ipvs protocol table.
  38  */
  39
  40 #define IP_VS_PROTO_TAB_SIZE            32      /* must be power of 2 */
  41 #define IP_VS_PROTO_HASH(proto)         ((proto) & (IP_VS_PROTO_TAB_SIZE-1))
  42
  43 static struct ip_vs_protocol *ip_vs_proto_table[IP_VS_PROTO_TAB_SIZE];
  44
  45 /* States for conn templates: NONE or words separated with ",", max 15 chars */
  46 static const char *ip_vs_ctpl_state_name_table[IP_VS_CTPL_S_LAST] = {
  47         [IP_VS_CTPL_S_NONE]                     = "NONE",
  48         [IP_VS_CTPL_S_ASSURED]                  = "ASSURED",
  49 };
  50
  51 /*
  52  *      register an ipvs protocol
  53  */
  54 static int __used __init register_ip_vs_protocol(struct ip_vs_protocol *pp)
  55 {
  56         unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
  57
  58         pp->next = ip_vs_proto_table[hash];
  59         ip_vs_proto_table[hash] = pp;
  60
  61         if (pp->init != NULL)
  62                 pp->init(pp);
  63
  64         return 0;
  65 }
  66
  67 /*
  68  *      register an ipvs protocols netns related data
  69  */
  70 static int
  71 register_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_protocol *pp)
  72 {
  73         unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
  74         struct ip_vs_proto_data *pd =
  75                         kzalloc(sizeof(struct ip_vs_proto_data), GFP_KERNEL);
  76
  77         if (!pd)
  78                 return -ENOMEM;
  79
  80         pd->pp = pp;    /* For speed issues */
  81         pd->next = ipvs->proto_data_table[hash];
  82         ipvs->proto_data_table[hash] = pd;
  83         atomic_set(&pd->appcnt, 0);     /* Init app counter */
  84
  85         if (pp->init_netns != NULL) {
  86                 int ret = pp->init_netns(ipvs, pd);
  87                 if (ret) {
  88                         /* unlink an free proto data */
  89                         ipvs->proto_data_table[hash] = pd->next;
  90                         kfree(pd);
  91                         return ret;
  92                 }
  93         }
  94
  95         return 0;
  96 }
  97
  98 /*
  99  *      unregister an ipvs protocol
 100  */
 101 static int unregister_ip_vs_protocol(struct ip_vs_protocol *pp)
 102 {
 103         struct ip_vs_protocol **pp_p;
 104         unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
 105
 106         pp_p = &ip_vs_proto_table[hash];
 107         for (; *pp_p; pp_p = &(*pp_p)->next) {
 108                 if (*pp_p == pp) {
 109                         *pp_p = pp->next;
 110                         if (pp->exit != NULL)
 111                                 pp->exit(pp);
 112                         return 0;
 113                 }
 114         }
 115
 116         return -ESRCH;
 117 }
 118
 119 /*
 120  *      unregister an ipvs protocols netns data
 121  */
 122 static int
 123 unregister_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd)
 124 {
 125         struct ip_vs_proto_data **pd_p;
 126         unsigned int hash = IP_VS_PROTO_HASH(pd->pp->protocol);
 127
 128         pd_p = &ipvs->proto_data_table[hash];
 129         for (; *pd_p; pd_p = &(*pd_p)->next) {
 130                 if (*pd_p == pd) {
 131                         *pd_p = pd->next;
 132                         if (pd->pp->exit_netns != NULL)
 133                                 pd->pp->exit_netns(ipvs, pd);
 134                         kfree(pd);
 135                         return 0;
 136                 }
 137         }
 138
 139         return -ESRCH;
 140 }
 141
 142 /*
 143  *      get ip_vs_protocol object by its proto.
 144  */
 145 struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto)
 146 {
 147         struct ip_vs_protocol *pp;
 148         unsigned int hash = IP_VS_PROTO_HASH(proto);
 149
 150         for (pp = ip_vs_proto_table[hash]; pp; pp = pp->next) {
 151                 if (pp->protocol == proto)
 152                         return pp;
 153         }
 154
 155         return NULL;
 156 }
 157 EXPORT_SYMBOL(ip_vs_proto_get);
 158
 159 /*
 160  *      get ip_vs_protocol object data by netns and proto
 161  */
 162 struct ip_vs_proto_data *
 163 ip_vs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto)
 164 {
 165         struct ip_vs_proto_data *pd;
 166         unsigned int hash = IP_VS_PROTO_HASH(proto);
 167
 168         for (pd = ipvs->proto_data_table[hash]; pd; pd = pd->next) {
 169                 if (pd->pp->protocol == proto)
 170                         return pd;
 171         }
 172
 173         return NULL;
 174 }
 175 EXPORT_SYMBOL(ip_vs_proto_data_get);
 176
 177 /*
 178  *      Propagate event for state change to all protocols
 179  */
 180 void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags)
 181 {
 182         struct ip_vs_proto_data *pd;
 183         int i;
 184
 185         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 186                 for (pd = ipvs->proto_data_table[i]; pd; pd = pd->next) {
 187                         if (pd->pp->timeout_change)
 188                                 pd->pp->timeout_change(pd, flags);
 189                 }
 190         }
 191 }
 192
 193
 194 int *
 195 ip_vs_create_timeout_table(int *table, int size)
 196 {
 197         return kmemdup(table, size, GFP_KERNEL);
 198 }
 199
 200
 201 const char *ip_vs_state_name(const struct ip_vs_conn *cp)
 202 {
 203         unsigned int state = cp->state;
 204         struct ip_vs_protocol *pp;
 205
 206         if (cp->flags & IP_VS_CONN_F_TEMPLATE) {
 207
 208                 if (state >= IP_VS_CTPL_S_LAST)
 209                         return "ERR!";
 210                 return ip_vs_ctpl_state_name_table[state] ? : "?";
 211         }
 212         pp = ip_vs_proto_get(cp->protocol);
 213         if (pp == NULL || pp->state_name == NULL)
 214                 return (cp->protocol == IPPROTO_IP) ? "NONE" : "ERR!";
 215         return pp->state_name(state);
 216 }
 217
 218
 219 static void
 220 ip_vs_tcpudp_debug_packet_v4(struct ip_vs_protocol *pp,
 221                              const struct sk_buff *skb,
 222                              int offset,
 223                              const char *msg)
 224 {
 225         char buf[128];
 226         struct iphdr _iph, *ih;
 227
 228         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 229         if (ih == NULL)
 230                 sprintf(buf, "TRUNCATED");
 231         else if (ih->frag_off & htons(IP_OFFSET))
 232                 sprintf(buf, "%pI4->%pI4 frag", &ih->saddr, &ih->daddr);
 233         else {
 234                 __be16 _ports[2], *pptr;
 235
 236                 pptr = skb_header_pointer(skb, offset + ih->ihl*4,
 237                                           sizeof(_ports), _ports);
 238                 if (pptr == NULL)
 239                         sprintf(buf, "TRUNCATED %pI4->%pI4",
 240                                 &ih->saddr, &ih->daddr);
 241                 else
 242                         sprintf(buf, "%pI4:%u->%pI4:%u",
 243                                 &ih->saddr, ntohs(pptr[0]),
 244                                 &ih->daddr, ntohs(pptr[1]));
 245         }
 246
 247         pr_debug("%s: %s %s\n", msg, pp->name, buf);
 248 }
 249
 250 #ifdef CONFIG_IP_VS_IPV6
 251 static void
 252 ip_vs_tcpudp_debug_packet_v6(struct ip_vs_protocol *pp,
 253                              const struct sk_buff *skb,
 254                              int offset,
 255                              const char *msg)
 256 {
 257         char buf[192];
 258         struct ipv6hdr _iph, *ih;
 259
 260         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 261         if (ih == NULL)
 262                 sprintf(buf, "TRUNCATED");
 263         else if (ih->nexthdr == IPPROTO_FRAGMENT)
 264                 sprintf(buf, "%pI6c->%pI6c frag", &ih->saddr, &ih->daddr);
 265         else {
 266                 __be16 _ports[2], *pptr;
 267
 268                 pptr = skb_header_pointer(skb, offset + sizeof(struct ipv6hdr),
 269                                           sizeof(_ports), _ports);
 270                 if (pptr == NULL)
 271                         sprintf(buf, "TRUNCATED %pI6c->%pI6c",
 272                                 &ih->saddr, &ih->daddr);
 273                 else
 274                         sprintf(buf, "%pI6c:%u->%pI6c:%u",
 275                                 &ih->saddr, ntohs(pptr[0]),
 276                                 &ih->daddr, ntohs(pptr[1]));
 277         }
 278
 279         pr_debug("%s: %s %s\n", msg, pp->name, buf);
 280 }
 281 #endif
 282
 283
 284 void
 285 ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
 286                           const struct sk_buff *skb,
 287                           int offset,
 288                           const char *msg)
 289 {
 290 #ifdef CONFIG_IP_VS_IPV6
 291         if (af == AF_INET6)
 292                 ip_vs_tcpudp_debug_packet_v6(pp, skb, offset, msg);
 293         else
 294 #endif
 295                 ip_vs_tcpudp_debug_packet_v4(pp, skb, offset, msg);
 296 }
 297
 298 /*
 299  * per network name-space init
 300  */
 301 int __net_init ip_vs_protocol_net_init(struct netns_ipvs *ipvs)
 302 {
 303         int i, ret;
 304         static struct ip_vs_protocol *protos[] = {
 305 #ifdef CONFIG_IP_VS_PROTO_TCP
 306         &ip_vs_protocol_tcp,
 307 #endif
 308 #ifdef CONFIG_IP_VS_PROTO_UDP
 309         &ip_vs_protocol_udp,
 310 #endif
 311 #ifdef CONFIG_IP_VS_PROTO_SCTP
 312         &ip_vs_protocol_sctp,
 313 #endif
 314 #ifdef CONFIG_IP_VS_PROTO_AH
 315         &ip_vs_protocol_ah,
 316 #endif
 317 #ifdef CONFIG_IP_VS_PROTO_ESP
 318         &ip_vs_protocol_esp,
 319 #endif
 320         };
 321
 322         for (i = 0; i < ARRAY_SIZE(protos); i++) {
 323                 ret = register_ip_vs_proto_netns(ipvs, protos[i]);
 324                 if (ret < 0)
 325                         goto cleanup;
 326         }
 327         return 0;
 328
 329 cleanup:
 330         ip_vs_protocol_net_cleanup(ipvs);
 331         return ret;
 332 }
 333
 334 void __net_exit ip_vs_protocol_net_cleanup(struct netns_ipvs *ipvs)
 335 {
 336         struct ip_vs_proto_data *pd;
 337         int i;
 338
 339         /* unregister all the ipvs proto data for this netns */
 340         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 341                 while ((pd = ipvs->proto_data_table[i]) != NULL)
 342                         unregister_ip_vs_proto_netns(ipvs, pd);
 343         }
 344 }
 345
 346 int __init ip_vs_protocol_init(void)
 347 {
 348         char protocols[64];
 349 #define REGISTER_PROTOCOL(p)                    \
 350         do {                                    \
 351                 register_ip_vs_protocol(p);     \
 352                 strcat(protocols, ", ");        \
 353                 strcat(protocols, (p)->name);   \
 354         } while (0)
 355
 356         protocols[0] = '\0';
 357         protocols[2] = '\0';
 358 #ifdef CONFIG_IP_VS_PROTO_TCP
 359         REGISTER_PROTOCOL(&ip_vs_protocol_tcp);
 360 #endif
 361 #ifdef CONFIG_IP_VS_PROTO_UDP
 362         REGISTER_PROTOCOL(&ip_vs_protocol_udp);
 363 #endif
 364 #ifdef CONFIG_IP_VS_PROTO_SCTP
 365         REGISTER_PROTOCOL(&ip_vs_protocol_sctp);
 366 #endif
 367 #ifdef CONFIG_IP_VS_PROTO_AH
 368         REGISTER_PROTOCOL(&ip_vs_protocol_ah);
 369 #endif
 370 #ifdef CONFIG_IP_VS_PROTO_ESP
 371         REGISTER_PROTOCOL(&ip_vs_protocol_esp);
 372 #endif
 373         pr_info("Registered protocols (%s)\n", &protocols[2]);
 374
 375         return 0;
 376 }
 377
 378
 379 void ip_vs_protocol_cleanup(void)
 380 {
 381         struct ip_vs_protocol *pp;
 382         int i;
 383
 384         /* unregister all the ipvs protocols */
 385         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 386                 while ((pp = ip_vs_proto_table[i]) != NULL)
 387                         unregister_ip_vs_protocol(pp);
 388         }
 389 }