linux/net/netfilter/ipvs/ip_vs_proto.c
<<
>>
Prefs
   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
  43static struct ip_vs_protocol *ip_vs_proto_table[IP_VS_PROTO_TAB_SIZE];
  44
  45
  46/*
  47 *      register an ipvs protocol
  48 */
  49static int __used __init register_ip_vs_protocol(struct ip_vs_protocol *pp)
  50{
  51        unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
  52
  53        pp->next = ip_vs_proto_table[hash];
  54        ip_vs_proto_table[hash] = pp;
  55
  56        if (pp->init != NULL)
  57                pp->init(pp);
  58
  59        return 0;
  60}
  61
  62/*
  63 *      register an ipvs protocols netns related data
  64 */
  65static int
  66register_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_protocol *pp)
  67{
  68        unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
  69        struct ip_vs_proto_data *pd =
  70                        kzalloc(sizeof(struct ip_vs_proto_data), GFP_KERNEL);
  71
  72        if (!pd)
  73                return -ENOMEM;
  74
  75        pd->pp = pp;    /* For speed issues */
  76        pd->next = ipvs->proto_data_table[hash];
  77        ipvs->proto_data_table[hash] = pd;
  78        atomic_set(&pd->appcnt, 0);     /* Init app counter */
  79
  80        if (pp->init_netns != NULL) {
  81                int ret = pp->init_netns(ipvs, pd);
  82                if (ret) {
  83                        /* unlink an free proto data */
  84                        ipvs->proto_data_table[hash] = pd->next;
  85                        kfree(pd);
  86                        return ret;
  87                }
  88        }
  89
  90        return 0;
  91}
  92
  93/*
  94 *      unregister an ipvs protocol
  95 */
  96static int unregister_ip_vs_protocol(struct ip_vs_protocol *pp)
  97{
  98        struct ip_vs_protocol **pp_p;
  99        unsigned int 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 */
 117static int
 118unregister_ip_vs_proto_netns(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd)
 119{
 120        struct ip_vs_proto_data **pd_p;
 121        unsigned int hash = IP_VS_PROTO_HASH(pd->pp->protocol);
 122
 123        pd_p = &ipvs->proto_data_table[hash];
 124        for (; *pd_p; pd_p = &(*pd_p)->next) {
 125                if (*pd_p == pd) {
 126                        *pd_p = pd->next;
 127                        if (pd->pp->exit_netns != NULL)
 128                                pd->pp->exit_netns(ipvs, pd);
 129                        kfree(pd);
 130                        return 0;
 131                }
 132        }
 133
 134        return -ESRCH;
 135}
 136
 137/*
 138 *      get ip_vs_protocol object by its proto.
 139 */
 140struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto)
 141{
 142        struct ip_vs_protocol *pp;
 143        unsigned int hash = IP_VS_PROTO_HASH(proto);
 144
 145        for (pp = ip_vs_proto_table[hash]; pp; pp = pp->next) {
 146                if (pp->protocol == proto)
 147                        return pp;
 148        }
 149
 150        return NULL;
 151}
 152EXPORT_SYMBOL(ip_vs_proto_get);
 153
 154/*
 155 *      get ip_vs_protocol object data by netns and proto
 156 */
 157struct ip_vs_proto_data *
 158ip_vs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto)
 159{
 160        struct ip_vs_proto_data *pd;
 161        unsigned int hash = IP_VS_PROTO_HASH(proto);
 162
 163        for (pd = ipvs->proto_data_table[hash]; pd; pd = pd->next) {
 164                if (pd->pp->protocol == proto)
 165                        return pd;
 166        }
 167
 168        return NULL;
 169}
 170EXPORT_SYMBOL(ip_vs_proto_data_get);
 171
 172/*
 173 *      Propagate event for state change to all protocols
 174 */
 175void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags)
 176{
 177        struct ip_vs_proto_data *pd;
 178        int i;
 179
 180        for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 181                for (pd = ipvs->proto_data_table[i]; pd; pd = pd->next) {
 182                        if (pd->pp->timeout_change)
 183                                pd->pp->timeout_change(pd, flags);
 184                }
 185        }
 186}
 187
 188
 189int *
 190ip_vs_create_timeout_table(int *table, int size)
 191{
 192        return kmemdup(table, size, GFP_KERNEL);
 193}
 194
 195
 196/*
 197 *      Set timeout value for state specified by name
 198 */
 199int
 200ip_vs_set_state_timeout(int *table, int num, const char *const *names,
 201                        const char *name, int to)
 202{
 203        int i;
 204
 205        if (!table || !name || !to)
 206                return -EINVAL;
 207
 208        for (i = 0; i < num; i++) {
 209                if (strcmp(names[i], name))
 210                        continue;
 211                table[i] = to * HZ;
 212                return 0;
 213        }
 214        return -ENOENT;
 215}
 216
 217
 218const char * ip_vs_state_name(__u16 proto, int state)
 219{
 220        struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
 221
 222        if (pp == NULL || pp->state_name == NULL)
 223                return (IPPROTO_IP == proto) ? "NONE" : "ERR!";
 224        return pp->state_name(state);
 225}
 226
 227
 228static void
 229ip_vs_tcpudp_debug_packet_v4(struct ip_vs_protocol *pp,
 230                             const struct sk_buff *skb,
 231                             int offset,
 232                             const char *msg)
 233{
 234        char buf[128];
 235        struct iphdr _iph, *ih;
 236
 237        ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 238        if (ih == NULL)
 239                sprintf(buf, "TRUNCATED");
 240        else if (ih->frag_off & htons(IP_OFFSET))
 241                sprintf(buf, "%pI4->%pI4 frag", &ih->saddr, &ih->daddr);
 242        else {
 243                __be16 _ports[2], *pptr;
 244
 245                pptr = skb_header_pointer(skb, offset + ih->ihl*4,
 246                                          sizeof(_ports), _ports);
 247                if (pptr == NULL)
 248                        sprintf(buf, "TRUNCATED %pI4->%pI4",
 249                                &ih->saddr, &ih->daddr);
 250                else
 251                        sprintf(buf, "%pI4:%u->%pI4:%u",
 252                                &ih->saddr, ntohs(pptr[0]),
 253                                &ih->daddr, ntohs(pptr[1]));
 254        }
 255
 256        pr_debug("%s: %s %s\n", msg, pp->name, buf);
 257}
 258
 259#ifdef CONFIG_IP_VS_IPV6
 260static void
 261ip_vs_tcpudp_debug_packet_v6(struct ip_vs_protocol *pp,
 262                             const struct sk_buff *skb,
 263                             int offset,
 264                             const char *msg)
 265{
 266        char buf[192];
 267        struct ipv6hdr _iph, *ih;
 268
 269        ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 270        if (ih == NULL)
 271                sprintf(buf, "TRUNCATED");
 272        else if (ih->nexthdr == IPPROTO_FRAGMENT)
 273                sprintf(buf, "%pI6c->%pI6c frag", &ih->saddr, &ih->daddr);
 274        else {
 275                __be16 _ports[2], *pptr;
 276
 277                pptr = skb_header_pointer(skb, offset + sizeof(struct ipv6hdr),
 278                                          sizeof(_ports), _ports);
 279                if (pptr == NULL)
 280                        sprintf(buf, "TRUNCATED %pI6c->%pI6c",
 281                                &ih->saddr, &ih->daddr);
 282                else
 283                        sprintf(buf, "%pI6c:%u->%pI6c:%u",
 284                                &ih->saddr, ntohs(pptr[0]),
 285                                &ih->daddr, ntohs(pptr[1]));
 286        }
 287
 288        pr_debug("%s: %s %s\n", msg, pp->name, buf);
 289}
 290#endif
 291
 292
 293void
 294ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
 295                          const struct sk_buff *skb,
 296                          int offset,
 297                          const char *msg)
 298{
 299#ifdef CONFIG_IP_VS_IPV6
 300        if (af == AF_INET6)
 301                ip_vs_tcpudp_debug_packet_v6(pp, skb, offset, msg);
 302        else
 303#endif
 304                ip_vs_tcpudp_debug_packet_v4(pp, skb, offset, msg);
 305}
 306
 307/*
 308 * per network name-space init
 309 */
 310int __net_init ip_vs_protocol_net_init(struct netns_ipvs *ipvs)
 311{
 312        int i, ret;
 313        static struct ip_vs_protocol *protos[] = {
 314#ifdef CONFIG_IP_VS_PROTO_TCP
 315        &ip_vs_protocol_tcp,
 316#endif
 317#ifdef CONFIG_IP_VS_PROTO_UDP
 318        &ip_vs_protocol_udp,
 319#endif
 320#ifdef CONFIG_IP_VS_PROTO_SCTP
 321        &ip_vs_protocol_sctp,
 322#endif
 323#ifdef CONFIG_IP_VS_PROTO_AH
 324        &ip_vs_protocol_ah,
 325#endif
 326#ifdef CONFIG_IP_VS_PROTO_ESP
 327        &ip_vs_protocol_esp,
 328#endif
 329        };
 330
 331        for (i = 0; i < ARRAY_SIZE(protos); i++) {
 332                ret = register_ip_vs_proto_netns(ipvs, protos[i]);
 333                if (ret < 0)
 334                        goto cleanup;
 335        }
 336        return 0;
 337
 338cleanup:
 339        ip_vs_protocol_net_cleanup(ipvs);
 340        return ret;
 341}
 342
 343void __net_exit ip_vs_protocol_net_cleanup(struct netns_ipvs *ipvs)
 344{
 345        struct ip_vs_proto_data *pd;
 346        int i;
 347
 348        /* unregister all the ipvs proto data for this netns */
 349        for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 350                while ((pd = ipvs->proto_data_table[i]) != NULL)
 351                        unregister_ip_vs_proto_netns(ipvs, pd);
 352        }
 353}
 354
 355int __init ip_vs_protocol_init(void)
 356{
 357        char protocols[64];
 358#define REGISTER_PROTOCOL(p)                    \
 359        do {                                    \
 360                register_ip_vs_protocol(p);     \
 361                strcat(protocols, ", ");        \
 362                strcat(protocols, (p)->name);   \
 363        } while (0)
 364
 365        protocols[0] = '\0';
 366        protocols[2] = '\0';
 367#ifdef CONFIG_IP_VS_PROTO_TCP
 368        REGISTER_PROTOCOL(&ip_vs_protocol_tcp);
 369#endif
 370#ifdef CONFIG_IP_VS_PROTO_UDP
 371        REGISTER_PROTOCOL(&ip_vs_protocol_udp);
 372#endif
 373#ifdef CONFIG_IP_VS_PROTO_SCTP
 374        REGISTER_PROTOCOL(&ip_vs_protocol_sctp);
 375#endif
 376#ifdef CONFIG_IP_VS_PROTO_AH
 377        REGISTER_PROTOCOL(&ip_vs_protocol_ah);
 378#endif
 379#ifdef CONFIG_IP_VS_PROTO_ESP
 380        REGISTER_PROTOCOL(&ip_vs_protocol_esp);
 381#endif
 382        pr_info("Registered protocols (%s)\n", &protocols[2]);
 383
 384        return 0;
 385}
 386
 387
 388void ip_vs_protocol_cleanup(void)
 389{
 390        struct ip_vs_protocol *pp;
 391        int i;
 392
 393        /* unregister all the ipvs protocols */
 394        for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 395                while ((pp = ip_vs_proto_table[i]) != NULL)
 396                        unregister_ip_vs_protocol(pp);
 397        }
 398}
 399